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6,549 | I am working as a beginning scientist and was given the management role for a small project (5 internal scientists, 1-2 external software contractors). What are the absolute essentials I need to manage this successfully?
There are several difficulties ahead right from the start:
* the project is already running and not progressing so well,
* my boss limits my time spent on this to 1-2 hours per week max,
* there is a large gap in understanding between the internal people and the external contractors (each are experienced in their knowledge domain),
* and I have zero experience in project management, both soft and hard skills.
A lot of good questions and answers on this site give advice how to do things 'right' if this is your primary job and domain of experience. However, I'm looking for a more minimalist answer within my constraints.
*How can a new PM manage a failing project in a few hours per week?*
---
A BIG THANK-YOU to all of you who answered this question. I greatly appreciate the thought and experience you put into your answers and they are very helpful. I have come to the conclusion that my first priorities must be to make a Gantt chart and to actively mediate regular communication between the other scientists on the project and our software contractors. My boss has clearly communicated his expectations, and now it's a matter of methodically determining whether they can be fulfilled.
I'd like to add a note here to explain the situation, because I got the feeling that some people were very surprised by this situation and thought it must be uncommon at best, negligent at worst. The fact is, most (all?) scientists in a leadership position are expected to manage multiple projects while additionally conducting their own research in the field, laboratory, or theoretical realm. At the same time, we must also regularly publish the results of our various projects in peer-reviewed journals and books -- ideally as soon as those results are produced ("publish or perish"). What's less common about my situation is that I am trying to manage a project which involves external contractors, and not just students and laboratory staff. However, as one moves up the academic ladder, one needs more and more skill in project management, and this is never actually taught to us. So my position is actually very common. I'm also sure that this sort of situation is not particular to academics -- as David Espina pointed out, project management is something that everyone has to do, but most of us aren't trained to do. | 2012/09/10 | [
"https://pm.stackexchange.com/questions/6549",
"https://pm.stackexchange.com",
"https://pm.stackexchange.com/users/4592/"
] | Let's be clear that project management has been a function of work long before it became a job role and a sort of profession. I'm quite sure you have far more project management experience than you are giving yourself credit for; after all, we begin managing projects about age 5.
The PM practices are really nothing more than a logical approach to doing work in an organized way. It is not some mystical rocket science thing for which you have to go to school. You do these things now. When you have time to study it, the class will put a name to it.
Don't overthink things. Just get yourself organized with the help of your team and learn to document what you are doing.
Your boss's expectation of a couple of hours a week is...his expectation. In reality, it will be what you need it to be, and as a leader you need to set that counter expectation. However, once things settle down, an hour or two a week on a five-person team is not unreasonable.
Then, when you have time, take some training. Until then, rely on your smarts and your previous project management experience which you do have. | As a starting project manager, I found Project Management for Dummies to be be really helpful. With your academic background, you could read it in a weekend. The reason I recommend this book is that not only does it touch upon aspects of methodology, it also talks about soft-skills like motivating people etc. and it sets just the right tone, being both accessible and having enough "meat" for you to work with. It won't teach you to be the perfect project manager but it will get you on track and start you asking the right questions. It also deals with basic tools like Gantt Charts etc.
Methodologies like PRINCE2 and PMBoK are great but they take a while to get your head around - and it sounds like you don't have the luxury of time.
Of course, I am sure there are lots of other great books about project management but that is one I am very familiar with. |
6,549 | I am working as a beginning scientist and was given the management role for a small project (5 internal scientists, 1-2 external software contractors). What are the absolute essentials I need to manage this successfully?
There are several difficulties ahead right from the start:
* the project is already running and not progressing so well,
* my boss limits my time spent on this to 1-2 hours per week max,
* there is a large gap in understanding between the internal people and the external contractors (each are experienced in their knowledge domain),
* and I have zero experience in project management, both soft and hard skills.
A lot of good questions and answers on this site give advice how to do things 'right' if this is your primary job and domain of experience. However, I'm looking for a more minimalist answer within my constraints.
*How can a new PM manage a failing project in a few hours per week?*
---
A BIG THANK-YOU to all of you who answered this question. I greatly appreciate the thought and experience you put into your answers and they are very helpful. I have come to the conclusion that my first priorities must be to make a Gantt chart and to actively mediate regular communication between the other scientists on the project and our software contractors. My boss has clearly communicated his expectations, and now it's a matter of methodically determining whether they can be fulfilled.
I'd like to add a note here to explain the situation, because I got the feeling that some people were very surprised by this situation and thought it must be uncommon at best, negligent at worst. The fact is, most (all?) scientists in a leadership position are expected to manage multiple projects while additionally conducting their own research in the field, laboratory, or theoretical realm. At the same time, we must also regularly publish the results of our various projects in peer-reviewed journals and books -- ideally as soon as those results are produced ("publish or perish"). What's less common about my situation is that I am trying to manage a project which involves external contractors, and not just students and laboratory staff. However, as one moves up the academic ladder, one needs more and more skill in project management, and this is never actually taught to us. So my position is actually very common. I'm also sure that this sort of situation is not particular to academics -- as David Espina pointed out, project management is something that everyone has to do, but most of us aren't trained to do. | 2012/09/10 | [
"https://pm.stackexchange.com/questions/6549",
"https://pm.stackexchange.com",
"https://pm.stackexchange.com/users/4592/"
] | It is possible that your boss hasn't really got a clue as to what a PM does. When I got my first PM job my boss thought all I needed to do was send out reminders and act as a stenographer at meetings. If this is the case you have a lot less work to do than if he wants you to act as a "true" PM. So the first thing that you need to do is talk to your boss and find out what his expectations are for someone in a PM role.
Assuming that you are to fulfill a "true" PM role, the [PRINCE2 principles](http://en.wikipedia.org/wiki/PRINCE2) will give you good guidance:
1. Focus on products. Know what your end product is and what it is composed of. Make sure all the work done is relevant to that product.
2. Ongoing business justification. The project has to provide value for money spent. Don't be afraid to suggest killing a project when the value isn't there.
3. Defined roles & responsibilities. Without this some work will slip through the cracks and won't get done, decisions won't be made or will be made by the wrong people, etc.
4. Management by stages. Break your project into at least a planning and an execution stage. At the end of each stage verify the business case is still valid, the plan is updated, etc and decide if you should carry on.
5. Management by exception. Set tolerances for decision making at different levels of authority so that decisions are made by appropriate people.
6. Learn from experience. Talk to other PMs and team members and find out how to approach the management and execution of the project. Don't be afraid to ask questions, with no experience you can't afford to be shy.
7. Tailor your approach. You will have problems both if you have too much and too little process and oversight associated with your project. With the amount of time you have available you probably can't go whole-hog with any PM methodology.
Beyond all of this, become zen with the fact that with the constraints put on you there is little chance that the original plan will succeed. Your task now is to come up with something that will work. | As others have pointed out, you can't really expect to accomplish your goal within those parameters.
In my opinion, the best you could do is try to switch over to an Agile team. The nice thing about the Agile process, if done correctly, is that it moves much of the decisions and problems facing management to the team itself. Rather than a manager identifying and solving a problem with the team, the team is encouraged to identify problems, propose and implement solutions and quantify results.
It can be difficult to implement without a coach or people who are already experienced, and it's just a waste of time to do a half-implementation because much of Agile is interdependent - removing up-front design without insisting on ruthless re-factoring would be futile. Ruthless re-factoring without full test coverage is dangerous, as is large-scale code sharing/re-factoring without pairing.
I just came from Nike where a huge chunk of their development has gone over to Agile. They had hired a coach/trainer full-time to train hundreds of developers. Even as a consultant they sent me to 3 full days of training.
It really can work well, and our reliance on management was minimal at that point. Our teams were 2 developers, 2 QAs and an analyst, with 3 of these teams under a team lead (not management) and a few hours of time with our "Customer" every two weeks to validate finished stories and choose new ones (this would probably be your role).
It's pretty hard to imagine until you've seen it operating smoothly though.
I suggest you check around for a successfull team that works within your parameters and try to copy their practice, but I can't imagine a team working within those parameters without being Agile (Heck, that should have been my whole answer!) |
6,549 | I am working as a beginning scientist and was given the management role for a small project (5 internal scientists, 1-2 external software contractors). What are the absolute essentials I need to manage this successfully?
There are several difficulties ahead right from the start:
* the project is already running and not progressing so well,
* my boss limits my time spent on this to 1-2 hours per week max,
* there is a large gap in understanding between the internal people and the external contractors (each are experienced in their knowledge domain),
* and I have zero experience in project management, both soft and hard skills.
A lot of good questions and answers on this site give advice how to do things 'right' if this is your primary job and domain of experience. However, I'm looking for a more minimalist answer within my constraints.
*How can a new PM manage a failing project in a few hours per week?*
---
A BIG THANK-YOU to all of you who answered this question. I greatly appreciate the thought and experience you put into your answers and they are very helpful. I have come to the conclusion that my first priorities must be to make a Gantt chart and to actively mediate regular communication between the other scientists on the project and our software contractors. My boss has clearly communicated his expectations, and now it's a matter of methodically determining whether they can be fulfilled.
I'd like to add a note here to explain the situation, because I got the feeling that some people were very surprised by this situation and thought it must be uncommon at best, negligent at worst. The fact is, most (all?) scientists in a leadership position are expected to manage multiple projects while additionally conducting their own research in the field, laboratory, or theoretical realm. At the same time, we must also regularly publish the results of our various projects in peer-reviewed journals and books -- ideally as soon as those results are produced ("publish or perish"). What's less common about my situation is that I am trying to manage a project which involves external contractors, and not just students and laboratory staff. However, as one moves up the academic ladder, one needs more and more skill in project management, and this is never actually taught to us. So my position is actually very common. I'm also sure that this sort of situation is not particular to academics -- as David Espina pointed out, project management is something that everyone has to do, but most of us aren't trained to do. | 2012/09/10 | [
"https://pm.stackexchange.com/questions/6549",
"https://pm.stackexchange.com",
"https://pm.stackexchange.com/users/4592/"
] | As others have pointed out, you can't really expect to accomplish your goal within those parameters.
In my opinion, the best you could do is try to switch over to an Agile team. The nice thing about the Agile process, if done correctly, is that it moves much of the decisions and problems facing management to the team itself. Rather than a manager identifying and solving a problem with the team, the team is encouraged to identify problems, propose and implement solutions and quantify results.
It can be difficult to implement without a coach or people who are already experienced, and it's just a waste of time to do a half-implementation because much of Agile is interdependent - removing up-front design without insisting on ruthless re-factoring would be futile. Ruthless re-factoring without full test coverage is dangerous, as is large-scale code sharing/re-factoring without pairing.
I just came from Nike where a huge chunk of their development has gone over to Agile. They had hired a coach/trainer full-time to train hundreds of developers. Even as a consultant they sent me to 3 full days of training.
It really can work well, and our reliance on management was minimal at that point. Our teams were 2 developers, 2 QAs and an analyst, with 3 of these teams under a team lead (not management) and a few hours of time with our "Customer" every two weeks to validate finished stories and choose new ones (this would probably be your role).
It's pretty hard to imagine until you've seen it operating smoothly though.
I suggest you check around for a successfull team that works within your parameters and try to copy their practice, but I can't imagine a team working within those parameters without being Agile (Heck, that should have been my whole answer!) | As a starting project manager, I found Project Management for Dummies to be be really helpful. With your academic background, you could read it in a weekend. The reason I recommend this book is that not only does it touch upon aspects of methodology, it also talks about soft-skills like motivating people etc. and it sets just the right tone, being both accessible and having enough "meat" for you to work with. It won't teach you to be the perfect project manager but it will get you on track and start you asking the right questions. It also deals with basic tools like Gantt Charts etc.
Methodologies like PRINCE2 and PMBoK are great but they take a while to get your head around - and it sounds like you don't have the luxury of time.
Of course, I am sure there are lots of other great books about project management but that is one I am very familiar with. |
6,595,272 | I've been reading quite a bit about Thrift and it looks like a technology I'd really like to use. I'm having all sorts of trouble building the Windows distribution. I know a patch exists to build a Windows version, however I have not had much luck with this either.
Does anyone know of a pre-built distribution for Windows?
Or any suggestions on how to get the latest version of Thrift built (without turning my Windows machine into a pseudo \*nix box).
Thanks
Rich | 2011/07/06 | [
"https://Stackoverflow.com/questions/6595272",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/74842/"
] | I ported the client part of Thrift to Windows C++ for my own open-source project. It should be easily usable in other Win32 or WinCE projects.
<http://peoplesnote.codeplex.com> - src\Evernote API\Thrift | Yes there is, just download the exe from here:
<http://thrift.apache.org/download/>
exe listed for download there is standalone executable, no installation is needed.
I have used it to generate Smalltalk code, did not test other languages. |
6,595,272 | I've been reading quite a bit about Thrift and it looks like a technology I'd really like to use. I'm having all sorts of trouble building the Windows distribution. I know a patch exists to build a Windows version, however I have not had much luck with this either.
Does anyone know of a pre-built distribution for Windows?
Or any suggestions on how to get the latest version of Thrift built (without turning my Windows machine into a pseudo \*nix box).
Thanks
Rich | 2011/07/06 | [
"https://Stackoverflow.com/questions/6595272",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/74842/"
] | Thrift 0.8 now has VS projects for both the compiler and C++ library. Get the snapshot release or the latest off of SVN
<http://thrift.apache.org/download/>
Edit: 0.8 has been officially released and the source is available as a tarball on the download page.
Edit2: The SVN trunk now has a cross-platform sample project under *thrift/contrib/transport-sample* | Yes there is, just download the exe from here:
<http://thrift.apache.org/download/>
exe listed for download there is standalone executable, no installation is needed.
I have used it to generate Smalltalk code, did not test other languages. |
6,595,272 | I've been reading quite a bit about Thrift and it looks like a technology I'd really like to use. I'm having all sorts of trouble building the Windows distribution. I know a patch exists to build a Windows version, however I have not had much luck with this either.
Does anyone know of a pre-built distribution for Windows?
Or any suggestions on how to get the latest version of Thrift built (without turning my Windows machine into a pseudo \*nix box).
Thanks
Rich | 2011/07/06 | [
"https://Stackoverflow.com/questions/6595272",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/74842/"
] | Thrift 0.8 now has VS projects for both the compiler and C++ library. Get the snapshot release or the latest off of SVN
<http://thrift.apache.org/download/>
Edit: 0.8 has been officially released and the source is available as a tarball on the download page.
Edit2: The SVN trunk now has a cross-platform sample project under *thrift/contrib/transport-sample* | I ported the client part of Thrift to Windows C++ for my own open-source project. It should be easily usable in other Win32 or WinCE projects.
<http://peoplesnote.codeplex.com> - src\Evernote API\Thrift |
400,590 | I have 6 1tb drives in a RAID5. 1 drive went down. On the RAID was 2 virtual machines that I really need back up and running. The spare drive I have to put in the server is a 1.5tb drive, which exceeds the physical per drive limit of the 2020SA. The drive is found in the disk utility, but it is not found in the array management section. I cannot add the drive to the array to have it rebuild.
I have a replacement drive along with some spares on their way from Newegg, but I am still looking at a few days of downtime. Is it possible to use the 5 working drives to get the VMs copied off and on to another server or do I just have to wait for the drives to get here? | 2012/06/20 | [
"https://serverfault.com/questions/400590",
"https://serverfault.com",
"https://serverfault.com/users/22230/"
] | The whole point of a Redundant Array of Inexpensive Disks is that there is redundancy built in, at some level. A raid 5 array should have survived a single disk loss. That card does support ot swap so the failure should have been invisible as far as IO is concerned. The max Array size (I think ) is only 2 TB so I wonder if your issue is compounded by creating an array too large? | >
> Is it possible to use the 5 working drives to get the VMs copied off
> and on to another server or do I just have to wait for the drives to
> get here?
>
>
>
Did the server actually go down? if so then the array's not doing what it should, i.e. allow you to survive a single disk failure, if it stayed up then you may as well copy the VMs off now, in fact I'd recommend it.
By the way, RAID 5 arrays of large disks, especially SATA ones is a terrible idea, search around on this site to spot the tails of woe from others in this situation. |
38,553 | I just get started three days ago. When meditating, I felt hard to breathe and even the lack of oxygen to the brain. I felt my bell and chess were stiff and this intervene me in getting enough oxygen. My posture is right (I so sure about that). How do I overcome it? Should I keep going or find some changes? | 2020/03/30 | [
"https://buddhism.stackexchange.com/questions/38553",
"https://buddhism.stackexchange.com",
"https://buddhism.stackexchange.com/users/18936/"
] | This could happen if you change your breathing pattern hence cutting off oxygen. As long as you breathe naturally there will be no issues.
---
In meditation, you are not support to hold your breath but to test your lungs you could try hold your breath for 10 seconds. If you cough or get any discomfort then it is best to get in touch with a doctor. | It sounds like you are concentrating on too many things at once, friend.
Perfect posture in the beginning stages of any breathing exercises will encourage strain because it takes a lot of effort to maintain that posture. The energy you put into the posture and the meditation is taking energy away from the breath.
The reason why is because we only have so much conscious energy to focus in the beginning of any cultivation. So when a guide says to get comfortable, it means that you are going to exercise (whether it is the mind, heart or body). Being comfortable during practice also encourages more control of ourselves and better chances of gaining insight into the technique we are practising.
Meditation is not just action for the mind, it is applicable to the body and heart as well. Focus too much on one part of the whole will neglect what is left and lead to imbalance. Meditation is the harmony of discipline and relief.
Cultivate in harmony |
38,553 | I just get started three days ago. When meditating, I felt hard to breathe and even the lack of oxygen to the brain. I felt my bell and chess were stiff and this intervene me in getting enough oxygen. My posture is right (I so sure about that). How do I overcome it? Should I keep going or find some changes? | 2020/03/30 | [
"https://buddhism.stackexchange.com/questions/38553",
"https://buddhism.stackexchange.com",
"https://buddhism.stackexchange.com/users/18936/"
] | When one fist starts meditating, one's mind is unused to the activity and may start to panic. When the mind panics, all sorts of weird threats and pains and bodily effects might appear; the mind is too attached to its own activity, and it starts to distort perception in order to give itself something to fuss over. This isn't about your breathing — breathing is something that will always 'just work', until the end of your days in this body — this is about your mind rushing around trying to fix things that aren't broken.
Relax, it will pass.
Remember, you're just sitting on a cushion, so the *absolute* worst that can happen is that you'll fall asleep and tip over like a character in a cartoon (and no, I've never seen that happen, so don't fret over that either). In a few days or weeks your mind will settle down and effects like this will go away. | It sounds like you are concentrating on too many things at once, friend.
Perfect posture in the beginning stages of any breathing exercises will encourage strain because it takes a lot of effort to maintain that posture. The energy you put into the posture and the meditation is taking energy away from the breath.
The reason why is because we only have so much conscious energy to focus in the beginning of any cultivation. So when a guide says to get comfortable, it means that you are going to exercise (whether it is the mind, heart or body). Being comfortable during practice also encourages more control of ourselves and better chances of gaining insight into the technique we are practising.
Meditation is not just action for the mind, it is applicable to the body and heart as well. Focus too much on one part of the whole will neglect what is left and lead to imbalance. Meditation is the harmony of discipline and relief.
Cultivate in harmony |
169,320 | The site which I maintain has been in production for 3 years. When you register, the site generates a large (20 digit) random hex password for you. It's stored MD5 hashed unsalted.
When I told the lead dev that MD5 is bad for passwords he said if bad guys get it there's no way they can crack it because the password is random. And even if the bad guy cracks it we generate it so users can't reuse it on other sites.
How can I convince him that we need to use best practices? He is very stubborn... | 2017/09/13 | [
"https://security.stackexchange.com/questions/169320",
"https://security.stackexchange.com",
"https://security.stackexchange.com/users/158889/"
] | As others have said, reversing the MD5 of an 80 bit random number is a hard problem, so if anyone obtained your table of hashes, they probably wouldn't be able to access user accounts.
However, you might want to consider where the users are storing those 80 bit random numbers. It probably isn't going to be in their heads. Best case, it's in a reasonably secure keychain or password repository app. Worst case, they'll have a file with PASSWORDS\_FOR\_YER\_APP.TXT in their home directory. | MD5 as you say is insecure, mainly because of discoveries in 2013 that allow it to be collision-attacked in 2^18 time (Apparently less than a second on modern machines).
Regardless of whether of not the password is going to be used on other sites, *your* site is still insecure. Just because it's random and thus won't appear on lookup tables of any kind, doesn't mean it can't be broken via collision. That means that if somebody gets the hash, they can pretty easily determine something that will function as a password, assuming you check the hashes.
As others have said, use a better method - SHA family are good, but many prefer SCrypt and BCrypt for passwords, and if its randomly generated passwords you're dealing with you probably won't need salt. |
24,547,438 | I need to know about how to use shared value objects in DDD Eg?
If i have two aggregates roots called **Registration and Admission,** both this aggregates consuming a value object called Address. even though my ubiquitous language are different (Admission address and registration address) the model of this Address object are same ( i meant it has common properties). so i decided to move this value object from both this aggregates roots to common place in my context ( Say SharedValuess). I like to know this practice is good or there any matured method available to handle this type of situations .
NB: This post may against the rules of Stack overflow because its answer is opinion based , but i didn't find any other active forum to ask this question. | 2014/07/03 | [
"https://Stackoverflow.com/questions/24547438",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/3196883/"
] | There is a pattern called "Shared kernel". It helps to avoid code duplication and usually used for bounded contexts integration. But I would recommend to keep it as little as possible to avoid leaking logic from bounded contexts.
I think in your case it would be a right decision to keep it shared unless you will need to have some differences in your address models for each of bounded contexts. | You having such dilemma might be an indication of something wrong with the model (UL). I would consider maintaining address in one of the two aggregate roots and reference this aggregate root 'by identity' from the other aggregate root.
[Aggregates in Domain Driven Design](http://codingcraft.wordpress.com/2014/08/17/aggregate-and-aggregate-root-in-domain-driven-desgn/) |
9,994,638 | I have an SSIS (2005) package that transforms some XML data and then imports it into SQL 2005. The column that the data goes to is nvarchar(max). The length of the data varies between 500 chars and 750 chars. When viewing the XML file that get created for import after the transform (XSLT) in Notepad ++ it is not truncated. the very next step in the package is the import to SQL Server. The data in the table after the import get truncated to about 450 or so chars. I know that in query analyzer you may not see all the data so I generated a script using SQL MGT Studio to script the table and the data and then viewed that in Notepad ++ and sure enough - the data had been truncated.
The SSIS package uses an XML Datasource to grab the transformed file. A Data Conversion (non-unicode to unicode for the nvarchar(max)) and an OLE DB Destination. | 2012/04/03 | [
"https://Stackoverflow.com/questions/9994638",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/87627/"
] | FYI - If anyone is interested I found the answer [here](http://blogs.msdn.com/b/rdoherty/archive/2005/03/16/396956.aspx) - scroll down by the bottom of the article where he describes "Show Advanced Editor..." for the XML Source item. This solved my issue perfectly. | You can also tell the component to ignore truncation by double clicking the XML source editor, selecting Error Output & set truncation to "ignore failure".
I find this useful for elements that I'm not even going to use in my data flow, one less thing to go wrong.
Re-sizing the data is the better option if you want to use column in your data flow. |
20,614 | It is believed that there is a black hole at the centre of the Milky Way galaxy. And the sun revolves around the centre of the milky way.
So does it mean our sun is revolving around the centre of the galaxy due to this black hole? | 2017/04/03 | [
"https://astronomy.stackexchange.com/questions/20614",
"https://astronomy.stackexchange.com",
"https://astronomy.stackexchange.com/users/16495/"
] | The Sun orbits in the entire Galactic gravitational potential, which is very approximately similar to that provided by considering that *all* the mass interior to its Galactic orbit (about 100 billion solar masses) were concentrated at the Galactic centre.
The black hole at the centre has a mass of 4 million Suns, so contributes less than 0.01% of the mass required to keep the Sun in its present Galactic orbit of about 200 million years. Or to put it another way, if the Sun just orbited the black hole with a period of 200 million years, we would need to be about 800 light years from the Galactic centre, rather than the 30,000 light years we presently are. | **Yes, of course**. In the same way as the answer to *If the Moon revolves around Earth, does it mean it revolves around you?* is Yes!
This does not mean, though, that you determine or even significantly affect the orbit of the Moon, and so it is with the supermassive black hole (SMBH) at the center of the Milky Way and the orbit of the Sun, as Rob explains (but fails to answer your question ;-).
The gravitational tug of the Milky Way at the Sun is the sum of the tugs of all its components, not just the SMBH. This is dominated by the vast number of stars (and dark matter), which together weight much more than the SMBH. |
4,710 | <https://worldbuilding.stackexchange.com/questions/74595/more-realistic-strength-stat>
**Worldbuilding:** It's too RPG-like.
**RPG:** D&D and reality can't be correlated, as long as the wisdom stat lives.
**Biology:** But it's for fictional system.
**Where to ask this question?** | 2017/03/20 | [
"https://worldbuilding.meta.stackexchange.com/questions/4710",
"https://worldbuilding.meta.stackexchange.com",
"https://worldbuilding.meta.stackexchange.com/users/32097/"
] | No philosophy is prohibited, but there are some things you should keep in mind:
1. Make sure that it is very clear that said philosophy is a philosophy of nation in your world, not yours. If it's also yours or not is irrelevant and best left out altogether.
2. Make sure that this is very clear it's not just one person. This would be story-based, see [Why is my question "Too Story Based" and how do I get it opened?](https://meta.worldbuilding.stackexchange.com/q/3300/49)
3. Make sure you clearly describe how this philosophy relate to the realities of fictional world you are building. Is it reasonable? Or bull excrement? In the fictional world we don't know, not in our real world.
* What is this philosophy? How does it work? What it assume?
* What in-world circumstances created it?
* Does it have real world analog, and what are the differences?
4. Provide clarifications requested.
5. Assume good faith - people comment to help you recover from bad question. Most of us are not native speakers so sometimes this may sound rough to you, and we have limited time and comment length (and patience), so we aren't always able to put enough "honey" in these comments. Deal with it and read carefully, without prejudice, what flaws in your questions these comments point out. You don't have to agree with them. But if these flaws are causing your question to get downvotes, show some gratitude for insight you got. **Comments on votes are not mandatory**, by commenting people are just trying to make you a favor.
I believe you failed at all these points.
---
*"Freedom of speech" is not a shield from consequences. We* acknowledge your right to post what you posted. But it's also our freedom of speech to vote it up or down or VTC, as we see fit. Calling it "spam voting" is unjust, you try to have your freedom of expression and at the same time take ours away.
\* by "we" I mean me and people who posted similar comments under original question(s). | To pretend that all of the votes on your question were purely about the quality of the question is more than a little disingenuous. Honestly I voted the way I did because the premise seemed thin and it made the question "not useful" as far as I was concerned, as I pointed out in the comments.
With that out of the way I would like to say a few things...
***steps up on his soap box***
People are going to ask questions that in some way involve their personal world view. Some will be offensive to you personally.\* That shouldn't be a reason to close a question out right, and as far as I know it isn't.
Please take these as opportunities to learn something, I personally learned a lot tonight. I didn't know that MGTOW was a thing and now I do. I don't agree with it or support it, but now I'm aware of it, and maybe being aware of an issue and talking to someone about it makes everyone involved a little better off.
People learn an awful lot from the stories they read, the games they play, and most essentially the worlds they interact with. If we can make our world a better place, by making our worlds/stories better, by taking the time to talk to someone we disagree with, everyone gains.
Your answer to a question may just change someone's point of view some day.\*\*
\*This is an unfortunate fact of life
\*\*With great power comes great responsibility... or some such... |
4,710 | <https://worldbuilding.stackexchange.com/questions/74595/more-realistic-strength-stat>
**Worldbuilding:** It's too RPG-like.
**RPG:** D&D and reality can't be correlated, as long as the wisdom stat lives.
**Biology:** But it's for fictional system.
**Where to ask this question?** | 2017/03/20 | [
"https://worldbuilding.meta.stackexchange.com/questions/4710",
"https://worldbuilding.meta.stackexchange.com",
"https://worldbuilding.meta.stackexchange.com/users/32097/"
] | We will not build your world for you
====================================
In general, questions of the sort...
*"Assume the world as we know it. Then I postulate that we change this one thing. Now tell me what the outcome is"*
...questions of that sort are of very poor quality by Stack Exchange standards and — in my personal opinion — quite annoying.
The poor quality is because they are very broad and as such have no clear answer. They could take any number of directions from there. As a questioner you need to limit the scope of the question, because otherwise you have just done the Stack Exchange equivalent of asking "Ok, so I throw two dice. What happens?".
**And the annoying bit is that the questioner is requesting that other people do the work that they themselves are meant to do.**
Ok, so you came up with a [High-concept](https://en.wikipedia.org/wiki/High-concept). That is all good, very clever of you to come up with it. I salute your ability to think out of the box. And this is usually the start for some really good and interesting world building.
But to then dump that concept in someone else's lap and say "Develop this for me. Come up with all the consequences and tell me what happens"... no. Just: no.
**We are not here to build your world for you.**
We are here to help you build your world on your own. When you get stuck in that process; when you have a specific problem that must be solved, that is when you post a question. If there are some kinks and wrinkles that need ironing, we can help you. If you need a way around an inconsistency in your logic; if you require justification that will allow you to astroturf the field for a specific world; if you need a fact- or reality check... then we can do that for you, and gladly so.
But we will not build your world for you. That is **your** job.
The "sin" of your question about fembots was that you did just that which I said above: you introduced a high-concept, but then you did not take that anywhere. You did not even **begin** to try to figure out what happens in a premise such as yours. You did not say anything about what possible routes this could take.
Instead you just dumped the premise on Worldbuilding and asked everyone else to develop the world for you. **That** was your sin. MGTOW had nothing to do with the down-votes.
A note on Freedom of Expression
-------------------------------
Freedom of Expression is a contract between you and the government. Freedom of Expression means that the government is not allowed to **censor** you, that is to say the government cannot demand to pre-approve that which you are about to express. (\*)
And that is all that it is.
**Freedom of Expression is NOT...**
* The right to demand to post anything, anywhere. People are not required to provide you with the means to express yourself. You have no right to conscript the usage of private assets — such as this forum — in order to express yourself. You are here as a **guest**, and your presence is by the good graces of the people responsible for Stack Exchange. The government is not an actor in this place, and so Freedom of Expression is not actually relevant here.
* The right to demand people approve of that which you express. It feels silly to have to point this out this but it must be said: even under Freedom of Expression, no-one is required to **like** that which you express. If the reader does not like it, they are entirely entitled to form and hold such an opinion, and they are at least as much as you within their rights to express this opinion.
* Immunity from criticism. See the point above. If people form the opinion that your posts are of such a quality that they do not approve of them, then they are within their rights to express this. And if they have valid arguments for their opinion, then it is the expressed **purpose** of the ratings and comments systems for them to use them to give you feedback as to why they think your post is of poor quality.
You cannot use "Freedom of Expression" as a shield against criticism.
* Immunity from other consequences. Freedom of Expression is not a "Get Out Of Jail Free" card, nor is it something you can invoke to escape other unpleasant consequences of that which you have expressed. Expressing yourself is an action. Actions may have consequences. Freedom of Expression does not exempt you from consequences. You are free to express yourself in the eyes of the government — they cannot stop you from doing it, even if they know what you are about to do and they do not like it — but you are not free from having to suffer for it, afterwards.
Whether this rhymes well with your concept of "freedom" or not can be debated, but these are — never the less — the facts.
EDIT: Thank you Frostfyre for [the mandatory xkcd reference](https://xkcd.com/1357/)...
[](https://i.stack.imgur.com/XoZiL.png)
(\*) Usually there are some more bits to this — such as for example in the Swedish Act of Freedom of Expression where it is stated that the government may not prevent you from **partaking of expressions** — but the main point is that the government may not try to stop you from expressing yourself. | To pretend that all of the votes on your question were purely about the quality of the question is more than a little disingenuous. Honestly I voted the way I did because the premise seemed thin and it made the question "not useful" as far as I was concerned, as I pointed out in the comments.
With that out of the way I would like to say a few things...
***steps up on his soap box***
People are going to ask questions that in some way involve their personal world view. Some will be offensive to you personally.\* That shouldn't be a reason to close a question out right, and as far as I know it isn't.
Please take these as opportunities to learn something, I personally learned a lot tonight. I didn't know that MGTOW was a thing and now I do. I don't agree with it or support it, but now I'm aware of it, and maybe being aware of an issue and talking to someone about it makes everyone involved a little better off.
People learn an awful lot from the stories they read, the games they play, and most essentially the worlds they interact with. If we can make our world a better place, by making our worlds/stories better, by taking the time to talk to someone we disagree with, everyone gains.
Your answer to a question may just change someone's point of view some day.\*\*
\*This is an unfortunate fact of life
\*\*With great power comes great responsibility... or some such... |
320,510 | What would be the easiest way to view classes, methods, properties, etc. inside a jar file?
I'm looking for something equivalent to the very useful *Lutz Roeder .NET Reflector* - for Java | 2008/11/26 | [
"https://Stackoverflow.com/questions/320510",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/28772/"
] | Eclipse 3.4 JDT
It is not the quickest way because you have to drag it into your eclipse first.
But you will have full java class browsing, even with decompile enabled. | You could try [JarSpy](http://sourceforge.net/project/showfiles.php?group_id=42094). There is an IDEA plugin version of it that I use. |
320,510 | What would be the easiest way to view classes, methods, properties, etc. inside a jar file?
I'm looking for something equivalent to the very useful *Lutz Roeder .NET Reflector* - for Java | 2008/11/26 | [
"https://Stackoverflow.com/questions/320510",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/28772/"
] | You can open them with most decompression utilities these days, then just get something like [DJ Java Decompiler](http://www.neshkov.com/) if you want to view the source. | I've set the default action in windows to "Open with WinZip". This makes it easy to manage JARs as archives. You can even add/remove files manually. |
320,510 | What would be the easiest way to view classes, methods, properties, etc. inside a jar file?
I'm looking for something equivalent to the very useful *Lutz Roeder .NET Reflector* - for Java | 2008/11/26 | [
"https://Stackoverflow.com/questions/320510",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/28772/"
] | **[Use WinRar](http://www.rarlab.com)**. It will open the folder structure for you in intact manner. Also allows in-archive editing, while preserving paths.
Afterall, a JAR file is a ZIP archive only. | On Mac there's [Jarzilla](http://code.google.com/p/jarzilla/) |
99,973 | This is a follow-up question inspired by [this question](https://rpg.stackexchange.com/questions/99966/when-merged-with-the-raven-using-soul-of-the-raven-is-the-warlock-immune-to-d).
While you're merged with your raven, if you take damage, how do you resolve it? It's not the same as a simple polymorph.
Do *both* you and the raven take the damage? Is it just you? If the raven *does* take the damage, what happens if it dies while you're merged with it? If it's just you, what happens to the raven/your body if you die? | 2017/05/17 | [
"https://rpg.stackexchange.com/questions/99973",
"https://rpg.stackexchange.com",
"https://rpg.stackexchange.com/users/4499/"
] | **Soul of the Raven** is described as
>
> As a Bonus action when your raven is perched on your shoulder, your body merges with your raven’s form. While merged, you become Tiny, you replace your speed with the raven’s, and you can use your action only to Dash, Disengage, Dodge, Help, Hide, or Search. During this time, you gain the benefits of your raven being perched on your shoulder. As an action, you and the raven return to normal.
>
>
>
It doesn't specify anything besides your size/speed change, so you retain all other stats. It is you who takes damage, with your AC and statistics. When **your** HP reaches 0, both of you die. There is nothing written about what happens to your shape when you die, so that would be up to the DM.
I personally would make you remain in raven form. You are merged until you decided not to be anymore. However, [The Raven Queen](https://rpg.stackexchange.com/users/34724/the-raven-queen) suggests that, as *"The raven vanishes when it dies, if you die, or if the two of you are separated by more than 5 miles."*, it makes more sense to change back into your form when you die since the raven you were merged with vanishes. | Since not other stated, i would assume it works like the druids **Wild Shape** ability, so the raven takes the damage and when he falls to 0 HP, he vanishes and you reappear.
Still, nothing is written about that, but i would handle it like that. So if the raven gets killed in the air... good Luck to you! |
99,973 | This is a follow-up question inspired by [this question](https://rpg.stackexchange.com/questions/99966/when-merged-with-the-raven-using-soul-of-the-raven-is-the-warlock-immune-to-d).
While you're merged with your raven, if you take damage, how do you resolve it? It's not the same as a simple polymorph.
Do *both* you and the raven take the damage? Is it just you? If the raven *does* take the damage, what happens if it dies while you're merged with it? If it's just you, what happens to the raven/your body if you die? | 2017/05/17 | [
"https://rpg.stackexchange.com/questions/99973",
"https://rpg.stackexchange.com",
"https://rpg.stackexchange.com/users/4499/"
] | The Soul of the Raven is an exension of Sentinel Raven
Sentinal Raven reads:
>
> While perched on your shoulder, the raven can’t be targeted by any attack or other harmful effect; only you can cast spells on it; it can’t take damage; and it is incapacitated.
>
>
>
Soul of the Raven Reads:
>
> As a bonus action when your raven is perched on your shoulder, your body merges with your raven’s form.
>
>
>
The intent is clearly that your raven can take no damage, so all damage to the merged form would occur to your HP.
>
> The raven vanishes when it dies, if you die, or if the two of you are separated...
>
>
>
This would imply that upon death, you'd become the PC form again, and the raven vanishes. | Since not other stated, i would assume it works like the druids **Wild Shape** ability, so the raven takes the damage and when he falls to 0 HP, he vanishes and you reappear.
Still, nothing is written about that, but i would handle it like that. So if the raven gets killed in the air... good Luck to you! |
99,973 | This is a follow-up question inspired by [this question](https://rpg.stackexchange.com/questions/99966/when-merged-with-the-raven-using-soul-of-the-raven-is-the-warlock-immune-to-d).
While you're merged with your raven, if you take damage, how do you resolve it? It's not the same as a simple polymorph.
Do *both* you and the raven take the damage? Is it just you? If the raven *does* take the damage, what happens if it dies while you're merged with it? If it's just you, what happens to the raven/your body if you die? | 2017/05/17 | [
"https://rpg.stackexchange.com/questions/99973",
"https://rpg.stackexchange.com",
"https://rpg.stackexchange.com/users/4499/"
] | **Soul of the Raven** is described as
>
> As a Bonus action when your raven is perched on your shoulder, your body merges with your raven’s form. While merged, you become Tiny, you replace your speed with the raven’s, and you can use your action only to Dash, Disengage, Dodge, Help, Hide, or Search. During this time, you gain the benefits of your raven being perched on your shoulder. As an action, you and the raven return to normal.
>
>
>
It doesn't specify anything besides your size/speed change, so you retain all other stats. It is you who takes damage, with your AC and statistics. When **your** HP reaches 0, both of you die. There is nothing written about what happens to your shape when you die, so that would be up to the DM.
I personally would make you remain in raven form. You are merged until you decided not to be anymore. However, [The Raven Queen](https://rpg.stackexchange.com/users/34724/the-raven-queen) suggests that, as *"The raven vanishes when it dies, if you die, or if the two of you are separated by more than 5 miles."*, it makes more sense to change back into your form when you die since the raven you were merged with vanishes. | The Soul of the Raven is an exension of Sentinel Raven
Sentinal Raven reads:
>
> While perched on your shoulder, the raven can’t be targeted by any attack or other harmful effect; only you can cast spells on it; it can’t take damage; and it is incapacitated.
>
>
>
Soul of the Raven Reads:
>
> As a bonus action when your raven is perched on your shoulder, your body merges with your raven’s form.
>
>
>
The intent is clearly that your raven can take no damage, so all damage to the merged form would occur to your HP.
>
> The raven vanishes when it dies, if you die, or if the two of you are separated...
>
>
>
This would imply that upon death, you'd become the PC form again, and the raven vanishes. |
4,698 | I want to make a very simple "escape the room" game. I was hoping for something that looks something like [this](http://www.escapetheroomgames.net/play-11952-raysroom.html). You would see images of some room and you click around to move or to add things to inventory. Then, you can select something in your inventory to use that item with something on the screen. During the whole game there would be a text box describing what is happening (probably in really broken English instead of Japanese).
I am looking for something that can be quite simple. I would prefer to have the ability to play sound (probably mp3's) when something happens. It can be web-based or a downloaded executable or .jar file. It doesn't have to be perfect, just a proof-of-concept really.
What is the best approach to get this game working with minimal effort? Are there some libraries that can help? I have plenty of Java experience and some C++, PHP, and others. I'd rather avoid Windows-based technology as I primarily run Linux. I am willing to learn other languages if they have a huge advantage.
Ideally, if someone could point me to an example program that I can modify. I'm not expecting to sell or distribute this game. | 2010/10/21 | [
"https://gamedev.stackexchange.com/questions/4698",
"https://gamedev.stackexchange.com",
"https://gamedev.stackexchange.com/users/2615/"
] | Personally, I'd recommend sticking to the programming language you know best, and checking out the graphic/audio libraries available to you. If you're familiar with Flash, there is a [tutorial on how to make a basic escape the room game](http://www.tutorialized.com/tutorial/Escape-the-Room-game-tutorial/33960). Even if you don't know Flash, that tutorial should help give you an idea as to how such games are constructed. | You have plenty of Java experience? Use Java.
[Famous games written in Java](https://gamedev.stackexchange.com/questions/3789/famous-games-written-in-java). |
4,698 | I want to make a very simple "escape the room" game. I was hoping for something that looks something like [this](http://www.escapetheroomgames.net/play-11952-raysroom.html). You would see images of some room and you click around to move or to add things to inventory. Then, you can select something in your inventory to use that item with something on the screen. During the whole game there would be a text box describing what is happening (probably in really broken English instead of Japanese).
I am looking for something that can be quite simple. I would prefer to have the ability to play sound (probably mp3's) when something happens. It can be web-based or a downloaded executable or .jar file. It doesn't have to be perfect, just a proof-of-concept really.
What is the best approach to get this game working with minimal effort? Are there some libraries that can help? I have plenty of Java experience and some C++, PHP, and others. I'd rather avoid Windows-based technology as I primarily run Linux. I am willing to learn other languages if they have a huge advantage.
Ideally, if someone could point me to an example program that I can modify. I'm not expecting to sell or distribute this game. | 2010/10/21 | [
"https://gamedev.stackexchange.com/questions/4698",
"https://gamedev.stackexchange.com",
"https://gamedev.stackexchange.com/users/2615/"
] | Personally, I'd recommend sticking to the programming language you know best, and checking out the graphic/audio libraries available to you. If you're familiar with Flash, there is a [tutorial on how to make a basic escape the room game](http://www.tutorialized.com/tutorial/Escape-the-Room-game-tutorial/33960). Even if you don't know Flash, that tutorial should help give you an idea as to how such games are constructed. | If you plan to stick with C++, you could give a try to Allegro ( <http://www.allegro.cc/> ) Simple to learn and suitable for what you need. Technically tough, I see this easier to build with PHP and some Javascript, without any libraries except maybe jQuery. It's all up to which language you're more comfortable with. |
4,698 | I want to make a very simple "escape the room" game. I was hoping for something that looks something like [this](http://www.escapetheroomgames.net/play-11952-raysroom.html). You would see images of some room and you click around to move or to add things to inventory. Then, you can select something in your inventory to use that item with something on the screen. During the whole game there would be a text box describing what is happening (probably in really broken English instead of Japanese).
I am looking for something that can be quite simple. I would prefer to have the ability to play sound (probably mp3's) when something happens. It can be web-based or a downloaded executable or .jar file. It doesn't have to be perfect, just a proof-of-concept really.
What is the best approach to get this game working with minimal effort? Are there some libraries that can help? I have plenty of Java experience and some C++, PHP, and others. I'd rather avoid Windows-based technology as I primarily run Linux. I am willing to learn other languages if they have a huge advantage.
Ideally, if someone could point me to an example program that I can modify. I'm not expecting to sell or distribute this game. | 2010/10/21 | [
"https://gamedev.stackexchange.com/questions/4698",
"https://gamedev.stackexchange.com",
"https://gamedev.stackexchange.com/users/2615/"
] | Personally, I'd recommend sticking to the programming language you know best, and checking out the graphic/audio libraries available to you. If you're familiar with Flash, there is a [tutorial on how to make a basic escape the room game](http://www.tutorialized.com/tutorial/Escape-the-Room-game-tutorial/33960). Even if you don't know Flash, that tutorial should help give you an idea as to how such games are constructed. | You can use the Wintermute adventure engine <http://dead-code.org/home/index.php/lang-pref/en/> |
4,698 | I want to make a very simple "escape the room" game. I was hoping for something that looks something like [this](http://www.escapetheroomgames.net/play-11952-raysroom.html). You would see images of some room and you click around to move or to add things to inventory. Then, you can select something in your inventory to use that item with something on the screen. During the whole game there would be a text box describing what is happening (probably in really broken English instead of Japanese).
I am looking for something that can be quite simple. I would prefer to have the ability to play sound (probably mp3's) when something happens. It can be web-based or a downloaded executable or .jar file. It doesn't have to be perfect, just a proof-of-concept really.
What is the best approach to get this game working with minimal effort? Are there some libraries that can help? I have plenty of Java experience and some C++, PHP, and others. I'd rather avoid Windows-based technology as I primarily run Linux. I am willing to learn other languages if they have a huge advantage.
Ideally, if someone could point me to an example program that I can modify. I'm not expecting to sell or distribute this game. | 2010/10/21 | [
"https://gamedev.stackexchange.com/questions/4698",
"https://gamedev.stackexchange.com",
"https://gamedev.stackexchange.com/users/2615/"
] | Personally, I'd recommend sticking to the programming language you know best, and checking out the graphic/audio libraries available to you. If you're familiar with Flash, there is a [tutorial on how to make a basic escape the room game](http://www.tutorialized.com/tutorial/Escape-the-Room-game-tutorial/33960). Even if you don't know Flash, that tutorial should help give you an idea as to how such games are constructed. | Take a look at Scratch: <http://www.scratch.org>
It was designed to teach kids, but it's very suitable for adults, and it's an absolutely wonderful prototyping engine.
It has an integrated audio sampler and image editor. You can also import images and audio files. It doesn't have a state mechanism, which could be useful in this type of game, but that's not really a major problem.
This is probably easier than just about any other approach, as the language uses a tile-based programming system (no code typing.) It works fine in Linux (I'm an Ubuntu guy myself) and it creates web friendly apps in a Java Applet container.
You could do this entirely in HTML and JavaScript, too. Use an imagemap for the background image (or small absolutely positioned elements.) You can keep track of your inventory with JavaScript code. You could also have the inventory pop up as a secondary window. |
4,698 | I want to make a very simple "escape the room" game. I was hoping for something that looks something like [this](http://www.escapetheroomgames.net/play-11952-raysroom.html). You would see images of some room and you click around to move or to add things to inventory. Then, you can select something in your inventory to use that item with something on the screen. During the whole game there would be a text box describing what is happening (probably in really broken English instead of Japanese).
I am looking for something that can be quite simple. I would prefer to have the ability to play sound (probably mp3's) when something happens. It can be web-based or a downloaded executable or .jar file. It doesn't have to be perfect, just a proof-of-concept really.
What is the best approach to get this game working with minimal effort? Are there some libraries that can help? I have plenty of Java experience and some C++, PHP, and others. I'd rather avoid Windows-based technology as I primarily run Linux. I am willing to learn other languages if they have a huge advantage.
Ideally, if someone could point me to an example program that I can modify. I'm not expecting to sell or distribute this game. | 2010/10/21 | [
"https://gamedev.stackexchange.com/questions/4698",
"https://gamedev.stackexchange.com",
"https://gamedev.stackexchange.com/users/2615/"
] | You have plenty of Java experience? Use Java.
[Famous games written in Java](https://gamedev.stackexchange.com/questions/3789/famous-games-written-in-java). | If you plan to stick with C++, you could give a try to Allegro ( <http://www.allegro.cc/> ) Simple to learn and suitable for what you need. Technically tough, I see this easier to build with PHP and some Javascript, without any libraries except maybe jQuery. It's all up to which language you're more comfortable with. |
4,698 | I want to make a very simple "escape the room" game. I was hoping for something that looks something like [this](http://www.escapetheroomgames.net/play-11952-raysroom.html). You would see images of some room and you click around to move or to add things to inventory. Then, you can select something in your inventory to use that item with something on the screen. During the whole game there would be a text box describing what is happening (probably in really broken English instead of Japanese).
I am looking for something that can be quite simple. I would prefer to have the ability to play sound (probably mp3's) when something happens. It can be web-based or a downloaded executable or .jar file. It doesn't have to be perfect, just a proof-of-concept really.
What is the best approach to get this game working with minimal effort? Are there some libraries that can help? I have plenty of Java experience and some C++, PHP, and others. I'd rather avoid Windows-based technology as I primarily run Linux. I am willing to learn other languages if they have a huge advantage.
Ideally, if someone could point me to an example program that I can modify. I'm not expecting to sell or distribute this game. | 2010/10/21 | [
"https://gamedev.stackexchange.com/questions/4698",
"https://gamedev.stackexchange.com",
"https://gamedev.stackexchange.com/users/2615/"
] | You have plenty of Java experience? Use Java.
[Famous games written in Java](https://gamedev.stackexchange.com/questions/3789/famous-games-written-in-java). | Take a look at Scratch: <http://www.scratch.org>
It was designed to teach kids, but it's very suitable for adults, and it's an absolutely wonderful prototyping engine.
It has an integrated audio sampler and image editor. You can also import images and audio files. It doesn't have a state mechanism, which could be useful in this type of game, but that's not really a major problem.
This is probably easier than just about any other approach, as the language uses a tile-based programming system (no code typing.) It works fine in Linux (I'm an Ubuntu guy myself) and it creates web friendly apps in a Java Applet container.
You could do this entirely in HTML and JavaScript, too. Use an imagemap for the background image (or small absolutely positioned elements.) You can keep track of your inventory with JavaScript code. You could also have the inventory pop up as a secondary window. |
4,698 | I want to make a very simple "escape the room" game. I was hoping for something that looks something like [this](http://www.escapetheroomgames.net/play-11952-raysroom.html). You would see images of some room and you click around to move or to add things to inventory. Then, you can select something in your inventory to use that item with something on the screen. During the whole game there would be a text box describing what is happening (probably in really broken English instead of Japanese).
I am looking for something that can be quite simple. I would prefer to have the ability to play sound (probably mp3's) when something happens. It can be web-based or a downloaded executable or .jar file. It doesn't have to be perfect, just a proof-of-concept really.
What is the best approach to get this game working with minimal effort? Are there some libraries that can help? I have plenty of Java experience and some C++, PHP, and others. I'd rather avoid Windows-based technology as I primarily run Linux. I am willing to learn other languages if they have a huge advantage.
Ideally, if someone could point me to an example program that I can modify. I'm not expecting to sell or distribute this game. | 2010/10/21 | [
"https://gamedev.stackexchange.com/questions/4698",
"https://gamedev.stackexchange.com",
"https://gamedev.stackexchange.com/users/2615/"
] | You can use the Wintermute adventure engine <http://dead-code.org/home/index.php/lang-pref/en/> | If you plan to stick with C++, you could give a try to Allegro ( <http://www.allegro.cc/> ) Simple to learn and suitable for what you need. Technically tough, I see this easier to build with PHP and some Javascript, without any libraries except maybe jQuery. It's all up to which language you're more comfortable with. |
4,698 | I want to make a very simple "escape the room" game. I was hoping for something that looks something like [this](http://www.escapetheroomgames.net/play-11952-raysroom.html). You would see images of some room and you click around to move or to add things to inventory. Then, you can select something in your inventory to use that item with something on the screen. During the whole game there would be a text box describing what is happening (probably in really broken English instead of Japanese).
I am looking for something that can be quite simple. I would prefer to have the ability to play sound (probably mp3's) when something happens. It can be web-based or a downloaded executable or .jar file. It doesn't have to be perfect, just a proof-of-concept really.
What is the best approach to get this game working with minimal effort? Are there some libraries that can help? I have plenty of Java experience and some C++, PHP, and others. I'd rather avoid Windows-based technology as I primarily run Linux. I am willing to learn other languages if they have a huge advantage.
Ideally, if someone could point me to an example program that I can modify. I'm not expecting to sell or distribute this game. | 2010/10/21 | [
"https://gamedev.stackexchange.com/questions/4698",
"https://gamedev.stackexchange.com",
"https://gamedev.stackexchange.com/users/2615/"
] | You can use the Wintermute adventure engine <http://dead-code.org/home/index.php/lang-pref/en/> | Take a look at Scratch: <http://www.scratch.org>
It was designed to teach kids, but it's very suitable for adults, and it's an absolutely wonderful prototyping engine.
It has an integrated audio sampler and image editor. You can also import images and audio files. It doesn't have a state mechanism, which could be useful in this type of game, but that's not really a major problem.
This is probably easier than just about any other approach, as the language uses a tile-based programming system (no code typing.) It works fine in Linux (I'm an Ubuntu guy myself) and it creates web friendly apps in a Java Applet container.
You could do this entirely in HTML and JavaScript, too. Use an imagemap for the background image (or small absolutely positioned elements.) You can keep track of your inventory with JavaScript code. You could also have the inventory pop up as a secondary window. |
541,035 | I searched about anything and refered by dictionary like below in the first quote
>
> anything : used to refer to a thing, no matter what.
>
>
>
so I'm curious "take anything selected" is meaning that take everything no matter what is selected?
I read this below sentence in the second quote, and don't figure out meaning of it
>
> Git takes anything selected and stages it for you
>
>
>
I want to know the meaning of this second quote. | 2020/07/17 | [
"https://english.stackexchange.com/questions/541035",
"https://english.stackexchange.com",
"https://english.stackexchange.com/users/390529/"
] | I prefer **impressionable**, as suggested by @KarimTabet, but I will add **gullible** and **credulous** to the possibilities he suggested. From Lexico:
>
> **[gullible](https://www.lexico.com/definition/gullible)**: Easily persuaded to believe something; credulous.
>
>
>
>
> **[credulous](https://www.lexico.com/definition/credulous)**: Having or showing too great a readiness to believe things.
>
>
>
"Someone whose personality or character changes a lot and get [sic] more affected than others by company or influential people" is more **impressionable**, gullible\*\*, or credulous\*\* than others. | It doesn't fit your sentence well, but the person could be considered a ***chameleon*** ([M/W def 2](https://www.merriam-webster.com/dictionary/chameleon))
>
> a person who often changes his or her beliefs or behavior in order to please others or to succeed
>
>
>
By analogy to an actual chameleon, which changes coloration to match its surroundings. |
541,035 | I searched about anything and refered by dictionary like below in the first quote
>
> anything : used to refer to a thing, no matter what.
>
>
>
so I'm curious "take anything selected" is meaning that take everything no matter what is selected?
I read this below sentence in the second quote, and don't figure out meaning of it
>
> Git takes anything selected and stages it for you
>
>
>
I want to know the meaning of this second quote. | 2020/07/17 | [
"https://english.stackexchange.com/questions/541035",
"https://english.stackexchange.com",
"https://english.stackexchange.com/users/390529/"
] | The person's personality would be described as [**malleable**](https://www.merriam-webster.com/dictionary/malleable):
>
> [Merriam-Webster]
>
> **2 a** : capable of being altered or controlled by outside forces or influences
>
>
>
Using it with the example sentence:
>
> He is a *malleable* type of person.
>
>
>
Or, more naturally:
>
> He is weak-willed, and has a *malleable* personality that is easily influenced and changed by others.
>
>
> | It doesn't fit your sentence well, but the person could be considered a ***chameleon*** ([M/W def 2](https://www.merriam-webster.com/dictionary/chameleon))
>
> a person who often changes his or her beliefs or behavior in order to please others or to succeed
>
>
>
By analogy to an actual chameleon, which changes coloration to match its surroundings. |
4,652 | How do we know that dark matter is dark, in the sense that it doesn't give out any light or absorb any? It is impossible for humans to be watching every single wavelength. For example, what about wavelengths that are too big to detect on Earth? | 2011/02/06 | [
"https://physics.stackexchange.com/questions/4652",
"https://physics.stackexchange.com",
"https://physics.stackexchange.com/users/4/"
] | There is indeed very good reason to believe dark matter is dark - apart from all the evidence from "missing mass" in luminosity counts and gravitational lensing studies.
This comes from theories of large-scale structure formation:
That there has always had to be some sort of matter that doesn't interact electromagnetically at all is crucial to most scenarios of large-scale structure formation. The density fluctuations in the present universe would be too large than what would be predicted if there were only ordinary baryonic matter that interacted only electromagnetically. With dark matter, you can have something that gravitates yet decouples from radiation much before baryonic matter does. This allows the dark matter to form gravitational wells (under collapse) which have a much longer time to expand with the universe. By the time ordinary matter decouples from radiation and joins the rest of the expansion flow, the ordinary matter will quickly fall into these large gravitational wells of the dark matter that have had far more time to grow. This, in a way, amplifies density perturbations in the early universe and allows large-scale structure to form. (to the extent that we see it today in the form of clusters and galaxies)
The required amount of dark matter calculated, in this way, in order to observe the present scale of density fluctuations matches very well with the amount of dark matter required to explain galactic rotation curves, gravitational lensing, etc. So there's excellent agreement that all of these are due to the same thing - some sort of matter which doesn't interact electromagnetically at all, viz. dark matter. | Adding two points that havent' been made here yet:
* I would argue that observations of Baryon-Acoustic Oscillations in the power spectrum of the Cosmic Microwave Background are actually the strongest evidence that the universe contains a large amount of matter that clumps under gravity but does not feel any photon pressure.
* Since dark matter doesn't interact via electromagnetic radiation, its name is a misnomer. It should be called transparent matter instead. |
4,652 | How do we know that dark matter is dark, in the sense that it doesn't give out any light or absorb any? It is impossible for humans to be watching every single wavelength. For example, what about wavelengths that are too big to detect on Earth? | 2011/02/06 | [
"https://physics.stackexchange.com/questions/4652",
"https://physics.stackexchange.com",
"https://physics.stackexchange.com/users/4/"
] | >
> **Note:** this answer is similar to [this one](https://physics.stackexchange.com/a/594505/251244) also written by me. [That question](https://physics.stackexchange.com/q/420288/251244) is very closely related and an interesting read.
>
>
>
>
> How do we know that dark matter is dark, in the sense that it doesn't give out any light or absorb any?
>
>
>
To answer your question, you need to understand how dark matter was hypothesised, so here is a summary:
>
> Using supercomputers, physicists were simulating the Big Bang and the formation of the Universe, applying Einstein's theories of special and general Relativity and Quantum Mechanics, experimenting with different variables to try to arrive at a system similar to our world as it is currently.
>
>
> As they experimented, they found that in the simulations generated by the supercomputers, the matter formed attracted each other *too weakly*; matter and gas were flung out too far during the Big Bang and could not "clump" together to form stars or planets.
>
>
> They tried adding some "dark matter"; matter which did not interact with the strong nuclear, weak nuclear, and electromagnetic force, i.e. it only interacted with ordinary matter gravitationally. This "placeholder mass" solved the problem, and the digital model successfully evolved to the system of the cosmos we observer today.
>
>
> The intriguing thing was that ~$85$% (!) of the universe had to be made up of this hypothesised "dark matter" so that it formed correctly.
>
>
>
**Conclusion:** the universe can't have existed without this mass made up of WIMPs (Weakly Interacting Massive Particles). So let's go look for it!
*Dark* matter is called *dark* because it is *hard to detect*, even though it is greatly abundant. It is hard to detect because it does not interact Nuclear-ly or electromagnetically, and photons (light particles) are electromagnetic particles. Physicist don't assume that it is weakly interacting, it was named "dark" because it is so. | Adding two points that havent' been made here yet:
* I would argue that observations of Baryon-Acoustic Oscillations in the power spectrum of the Cosmic Microwave Background are actually the strongest evidence that the universe contains a large amount of matter that clumps under gravity but does not feel any photon pressure.
* Since dark matter doesn't interact via electromagnetic radiation, its name is a misnomer. It should be called transparent matter instead. |
4,652 | How do we know that dark matter is dark, in the sense that it doesn't give out any light or absorb any? It is impossible for humans to be watching every single wavelength. For example, what about wavelengths that are too big to detect on Earth? | 2011/02/06 | [
"https://physics.stackexchange.com/questions/4652",
"https://physics.stackexchange.com",
"https://physics.stackexchange.com/users/4/"
] | There is indeed very good reason to believe dark matter is dark - apart from all the evidence from "missing mass" in luminosity counts and gravitational lensing studies.
This comes from theories of large-scale structure formation:
That there has always had to be some sort of matter that doesn't interact electromagnetically at all is crucial to most scenarios of large-scale structure formation. The density fluctuations in the present universe would be too large than what would be predicted if there were only ordinary baryonic matter that interacted only electromagnetically. With dark matter, you can have something that gravitates yet decouples from radiation much before baryonic matter does. This allows the dark matter to form gravitational wells (under collapse) which have a much longer time to expand with the universe. By the time ordinary matter decouples from radiation and joins the rest of the expansion flow, the ordinary matter will quickly fall into these large gravitational wells of the dark matter that have had far more time to grow. This, in a way, amplifies density perturbations in the early universe and allows large-scale structure to form. (to the extent that we see it today in the form of clusters and galaxies)
The required amount of dark matter calculated, in this way, in order to observe the present scale of density fluctuations matches very well with the amount of dark matter required to explain galactic rotation curves, gravitational lensing, etc. So there's excellent agreement that all of these are due to the same thing - some sort of matter which doesn't interact electromagnetically at all, viz. dark matter. | >
> **Note:** this answer is similar to [this one](https://physics.stackexchange.com/a/594505/251244) also written by me. [That question](https://physics.stackexchange.com/q/420288/251244) is very closely related and an interesting read.
>
>
>
>
> How do we know that dark matter is dark, in the sense that it doesn't give out any light or absorb any?
>
>
>
To answer your question, you need to understand how dark matter was hypothesised, so here is a summary:
>
> Using supercomputers, physicists were simulating the Big Bang and the formation of the Universe, applying Einstein's theories of special and general Relativity and Quantum Mechanics, experimenting with different variables to try to arrive at a system similar to our world as it is currently.
>
>
> As they experimented, they found that in the simulations generated by the supercomputers, the matter formed attracted each other *too weakly*; matter and gas were flung out too far during the Big Bang and could not "clump" together to form stars or planets.
>
>
> They tried adding some "dark matter"; matter which did not interact with the strong nuclear, weak nuclear, and electromagnetic force, i.e. it only interacted with ordinary matter gravitationally. This "placeholder mass" solved the problem, and the digital model successfully evolved to the system of the cosmos we observer today.
>
>
> The intriguing thing was that ~$85$% (!) of the universe had to be made up of this hypothesised "dark matter" so that it formed correctly.
>
>
>
**Conclusion:** the universe can't have existed without this mass made up of WIMPs (Weakly Interacting Massive Particles). So let's go look for it!
*Dark* matter is called *dark* because it is *hard to detect*, even though it is greatly abundant. It is hard to detect because it does not interact Nuclear-ly or electromagnetically, and photons (light particles) are electromagnetic particles. Physicist don't assume that it is weakly interacting, it was named "dark" because it is so. |
4,652 | How do we know that dark matter is dark, in the sense that it doesn't give out any light or absorb any? It is impossible for humans to be watching every single wavelength. For example, what about wavelengths that are too big to detect on Earth? | 2011/02/06 | [
"https://physics.stackexchange.com/questions/4652",
"https://physics.stackexchange.com",
"https://physics.stackexchange.com/users/4/"
] | There is indeed very good reason to believe dark matter is dark - apart from all the evidence from "missing mass" in luminosity counts and gravitational lensing studies.
This comes from theories of large-scale structure formation:
That there has always had to be some sort of matter that doesn't interact electromagnetically at all is crucial to most scenarios of large-scale structure formation. The density fluctuations in the present universe would be too large than what would be predicted if there were only ordinary baryonic matter that interacted only electromagnetically. With dark matter, you can have something that gravitates yet decouples from radiation much before baryonic matter does. This allows the dark matter to form gravitational wells (under collapse) which have a much longer time to expand with the universe. By the time ordinary matter decouples from radiation and joins the rest of the expansion flow, the ordinary matter will quickly fall into these large gravitational wells of the dark matter that have had far more time to grow. This, in a way, amplifies density perturbations in the early universe and allows large-scale structure to form. (to the extent that we see it today in the form of clusters and galaxies)
The required amount of dark matter calculated, in this way, in order to observe the present scale of density fluctuations matches very well with the amount of dark matter required to explain galactic rotation curves, gravitational lensing, etc. So there's excellent agreement that all of these are due to the same thing - some sort of matter which doesn't interact electromagnetically at all, viz. dark matter. | Dark matter was originally called that because it was matter.... that was dark. In other words, it was inferred that there must be something out there, in galaxies and in clusters of galaxies, that had a gravitational effect, but which could not be readily detected using electromagnetic waves at any wavelength.
Now initially it was thought that this "dark matter" could just be stuff that was hard to detect and that had a large mass-to-light ratio. An example would be lost golf balls. Golf balls do not emit very much light - well, not unless you make them very hot. On the other hand they do have mass. If you have enough (cold) golf balls then it could be that all those lost golf balls explain why galaxies rotate too fast as a function of radius or why the galaxy velocity dispersion in galaxy clusters seems to high for the amount of luminous matter that can be accounted for. More seriously, the cosmic lost golf balls that have been considered were very faint stars, cold brown dwarfs, old white dwarfs or perhaps lots and lots of planets or mini-black holes.
Pretty much all of these possibilities have now been excluded (primordial black holes may still be a possibility) using, for example, transit and microlensing experiments.
At the same time, what we mean by "dark matter" has evolved to mean *non-baryonic* dark matter. This is not just matter which is faint, but matter which does not interact electromagnetically at all. Such matter is by definition, absolutely dark.
Why is such a material proposed? Well firstly there is the failure to detect enough baryonic dark matter (i.e. the lost golf balls which are just very dim), which does interact electromagnetically but is just dim. Secondly, we know how much baryonic matter there is in the universe by estimating the primordial abundances of helium and deuterium produced in the big bang. The amount falls short by a factor of about 6 of the amount of gravitating matter required to explain the dynamics of the universe, galaxies and galaxy clusters. The remaining 5/6 must be non-baryonic and since we can't have charged leptons like electrons without an equal number of positively charged baryons, then it does not interact electromagnetically either (any quantity of positrons would have annihilated long ago). It is therefore, by definition, dark at all wavelengths. |
4,652 | How do we know that dark matter is dark, in the sense that it doesn't give out any light or absorb any? It is impossible for humans to be watching every single wavelength. For example, what about wavelengths that are too big to detect on Earth? | 2011/02/06 | [
"https://physics.stackexchange.com/questions/4652",
"https://physics.stackexchange.com",
"https://physics.stackexchange.com/users/4/"
] | There is indeed very good reason to believe dark matter is dark - apart from all the evidence from "missing mass" in luminosity counts and gravitational lensing studies.
This comes from theories of large-scale structure formation:
That there has always had to be some sort of matter that doesn't interact electromagnetically at all is crucial to most scenarios of large-scale structure formation. The density fluctuations in the present universe would be too large than what would be predicted if there were only ordinary baryonic matter that interacted only electromagnetically. With dark matter, you can have something that gravitates yet decouples from radiation much before baryonic matter does. This allows the dark matter to form gravitational wells (under collapse) which have a much longer time to expand with the universe. By the time ordinary matter decouples from radiation and joins the rest of the expansion flow, the ordinary matter will quickly fall into these large gravitational wells of the dark matter that have had far more time to grow. This, in a way, amplifies density perturbations in the early universe and allows large-scale structure to form. (to the extent that we see it today in the form of clusters and galaxies)
The required amount of dark matter calculated, in this way, in order to observe the present scale of density fluctuations matches very well with the amount of dark matter required to explain galactic rotation curves, gravitational lensing, etc. So there's excellent agreement that all of these are due to the same thing - some sort of matter which doesn't interact electromagnetically at all, viz. dark matter. | Aside from the very good theoretical reasons dbrane gives, I'd say that we don't have observational evidence that DM is truly dark. Some of the largely discredited MACHO candidates, like large numbers of red dwarfs, brown dwarfs, planetissimals etc. have been rejected for theoretical -not observational reasons. DM, that is lightly emitting is not currently detectable. |
718,833 | I am displaying calendar using calendar control.
Each date is displayed as Link button.
But i want only last 30 days(dates) from current date, to be enabled for client click. on those days i will write some code on SelectionChanged event. But goal is other dates must be disabled for click.
They should not have link button. | 2009/04/05 | [
"https://Stackoverflow.com/questions/718833",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/415865/"
] | A few reasons:
1. POP3 does need far less server side
storage.
2. POP3 is much easier to implement.
3. POP3 is private by default (it
assumes that you want to delete
email off the server after
downloading it).
4. Initially almost all ISPs had tiny
storage limits (since their are free
large storage email services this
matters less now) so deleting emails
that you downloaded was a must.
5. (for completeness - thanks Evan) POP
clients open a TCP/IP connection to
the server, authenticates itself,
asks for any email and does whatever
processing it needs, and then close
the connection. IMAP clients
generally keep one or more TCP/IP
sockets open with the server the
whole time they are running, taking
up those resources.
6. POP is a much simpler protocol to implement and can handle a greater number of clients with the same amount of resources. | Yahoo mail still does not offer IMAP. My guess is that it's because I'm more likely to use their site than Outlook, meaning I'll have to see their ads. |
718,833 | I am displaying calendar using calendar control.
Each date is displayed as Link button.
But i want only last 30 days(dates) from current date, to be enabled for client click. on those days i will write some code on SelectionChanged event. But goal is other dates must be disabled for click.
They should not have link button. | 2009/04/05 | [
"https://Stackoverflow.com/questions/718833",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/415865/"
] | I think part of it is that IMAP is usually used in scenarios where the emails are retained on the server, whereas POP is used almost exclusively for situations where the email is downloaded to the local machine, which is what most ISPs providing email facilities for their customers want you to do (and also what most of the customers probably want as well, although less so as they get more exposure to the Internet and things like gmail and yahoo, etc.)
Another reason it is probably preferred by email providers is that it does polling, much like an RSS news reader. The POP client will open a TCP/IP connection to the server, authenticate itself, ask for any email and do whatever processing it needs, and then close the connection.
IMAP clients generally keep one or more TCP/IP sockets open with the server the whole time they are running, taking up those resources. Yet another reason for ISPs to prefer POP.
Google mail supports both POP and IMAP protocols.
(P.S. I do not mean to sound like I am having a go at ISPs. I think the reasons I've attributed to them above are very pragmatic and sensible.) | Another reason is POP3 fetchers. You may have a central IMAP mailbox where you want to download mail from all other accounts of yours to keep all your mail in same place. This is usually done with POP3 fetchers which poll your other mailboxes periodically and load mail from there in your primary mailbox.
Although IMAP fetchers do exist, most of fetchers are still POP3-only and if your other mailbox does not support POP3, you may have troubles using a fetcher to link it with your primary mailbox. |
718,833 | I am displaying calendar using calendar control.
Each date is displayed as Link button.
But i want only last 30 days(dates) from current date, to be enabled for client click. on those days i will write some code on SelectionChanged event. But goal is other dates must be disabled for click.
They should not have link button. | 2009/04/05 | [
"https://Stackoverflow.com/questions/718833",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/415865/"
] | A few reasons:
1. POP3 does need far less server side
storage.
2. POP3 is much easier to implement.
3. POP3 is private by default (it
assumes that you want to delete
email off the server after
downloading it).
4. Initially almost all ISPs had tiny
storage limits (since their are free
large storage email services this
matters less now) so deleting emails
that you downloaded was a must.
5. (for completeness - thanks Evan) POP
clients open a TCP/IP connection to
the server, authenticates itself,
asks for any email and does whatever
processing it needs, and then close
the connection. IMAP clients
generally keep one or more TCP/IP
sockets open with the server the
whole time they are running, taking
up those resources.
6. POP is a much simpler protocol to implement and can handle a greater number of clients with the same amount of resources. | Another reason is POP3 fetchers. You may have a central IMAP mailbox where you want to download mail from all other accounts of yours to keep all your mail in same place. This is usually done with POP3 fetchers which poll your other mailboxes periodically and load mail from there in your primary mailbox.
Although IMAP fetchers do exist, most of fetchers are still POP3-only and if your other mailbox does not support POP3, you may have troubles using a fetcher to link it with your primary mailbox. |
718,833 | I am displaying calendar using calendar control.
Each date is displayed as Link button.
But i want only last 30 days(dates) from current date, to be enabled for client click. on those days i will write some code on SelectionChanged event. But goal is other dates must be disabled for click.
They should not have link button. | 2009/04/05 | [
"https://Stackoverflow.com/questions/718833",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/415865/"
] | Because POP3 does not need as much storage on the server side. And because it is more simple and easy to implement. | Another reason is POP3 fetchers. You may have a central IMAP mailbox where you want to download mail from all other accounts of yours to keep all your mail in same place. This is usually done with POP3 fetchers which poll your other mailboxes periodically and load mail from there in your primary mailbox.
Although IMAP fetchers do exist, most of fetchers are still POP3-only and if your other mailbox does not support POP3, you may have troubles using a fetcher to link it with your primary mailbox. |
718,833 | I am displaying calendar using calendar control.
Each date is displayed as Link button.
But i want only last 30 days(dates) from current date, to be enabled for client click. on those days i will write some code on SelectionChanged event. But goal is other dates must be disabled for click.
They should not have link button. | 2009/04/05 | [
"https://Stackoverflow.com/questions/718833",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/415865/"
] | Because POP3 does not need as much storage on the server side. And because it is more simple and easy to implement. | Many email services (such as those provided by ISPs) only offer a limited size mailbox. This makes it necessary to download your messages to your computer to be able to store the large number of emails that are common these days. |
718,833 | I am displaying calendar using calendar control.
Each date is displayed as Link button.
But i want only last 30 days(dates) from current date, to be enabled for client click. on those days i will write some code on SelectionChanged event. But goal is other dates must be disabled for click.
They should not have link button. | 2009/04/05 | [
"https://Stackoverflow.com/questions/718833",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/415865/"
] | Yahoo mail still does not offer IMAP. My guess is that it's because I'm more likely to use their site than Outlook, meaning I'll have to see their ads. | Another reason is POP3 fetchers. You may have a central IMAP mailbox where you want to download mail from all other accounts of yours to keep all your mail in same place. This is usually done with POP3 fetchers which poll your other mailboxes periodically and load mail from there in your primary mailbox.
Although IMAP fetchers do exist, most of fetchers are still POP3-only and if your other mailbox does not support POP3, you may have troubles using a fetcher to link it with your primary mailbox. |
718,833 | I am displaying calendar using calendar control.
Each date is displayed as Link button.
But i want only last 30 days(dates) from current date, to be enabled for client click. on those days i will write some code on SelectionChanged event. But goal is other dates must be disabled for click.
They should not have link button. | 2009/04/05 | [
"https://Stackoverflow.com/questions/718833",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/415865/"
] | A few reasons:
1. POP3 does need far less server side
storage.
2. POP3 is much easier to implement.
3. POP3 is private by default (it
assumes that you want to delete
email off the server after
downloading it).
4. Initially almost all ISPs had tiny
storage limits (since their are free
large storage email services this
matters less now) so deleting emails
that you downloaded was a must.
5. (for completeness - thanks Evan) POP
clients open a TCP/IP connection to
the server, authenticates itself,
asks for any email and does whatever
processing it needs, and then close
the connection. IMAP clients
generally keep one or more TCP/IP
sockets open with the server the
whole time they are running, taking
up those resources.
6. POP is a much simpler protocol to implement and can handle a greater number of clients with the same amount of resources. | Many email services (such as those provided by ISPs) only offer a limited size mailbox. This makes it necessary to download your messages to your computer to be able to store the large number of emails that are common these days. |
718,833 | I am displaying calendar using calendar control.
Each date is displayed as Link button.
But i want only last 30 days(dates) from current date, to be enabled for client click. on those days i will write some code on SelectionChanged event. But goal is other dates must be disabled for click.
They should not have link button. | 2009/04/05 | [
"https://Stackoverflow.com/questions/718833",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/415865/"
] | Because POP3 does not need as much storage on the server side. And because it is more simple and easy to implement. | I think part of it is that IMAP is usually used in scenarios where the emails are retained on the server, whereas POP is used almost exclusively for situations where the email is downloaded to the local machine, which is what most ISPs providing email facilities for their customers want you to do (and also what most of the customers probably want as well, although less so as they get more exposure to the Internet and things like gmail and yahoo, etc.)
Another reason it is probably preferred by email providers is that it does polling, much like an RSS news reader. The POP client will open a TCP/IP connection to the server, authenticate itself, ask for any email and do whatever processing it needs, and then close the connection.
IMAP clients generally keep one or more TCP/IP sockets open with the server the whole time they are running, taking up those resources. Yet another reason for ISPs to prefer POP.
Google mail supports both POP and IMAP protocols.
(P.S. I do not mean to sound like I am having a go at ISPs. I think the reasons I've attributed to them above are very pragmatic and sensible.) |
718,833 | I am displaying calendar using calendar control.
Each date is displayed as Link button.
But i want only last 30 days(dates) from current date, to be enabled for client click. on those days i will write some code on SelectionChanged event. But goal is other dates must be disabled for click.
They should not have link button. | 2009/04/05 | [
"https://Stackoverflow.com/questions/718833",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/415865/"
] | Yahoo mail still does not offer IMAP. My guess is that it's because I'm more likely to use their site than Outlook, meaning I'll have to see their ads. | Many email services (such as those provided by ISPs) only offer a limited size mailbox. This makes it necessary to download your messages to your computer to be able to store the large number of emails that are common these days. |
718,833 | I am displaying calendar using calendar control.
Each date is displayed as Link button.
But i want only last 30 days(dates) from current date, to be enabled for client click. on those days i will write some code on SelectionChanged event. But goal is other dates must be disabled for click.
They should not have link button. | 2009/04/05 | [
"https://Stackoverflow.com/questions/718833",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/415865/"
] | Because POP3 does not need as much storage on the server side. And because it is more simple and easy to implement. | A few reasons:
1. POP3 does need far less server side
storage.
2. POP3 is much easier to implement.
3. POP3 is private by default (it
assumes that you want to delete
email off the server after
downloading it).
4. Initially almost all ISPs had tiny
storage limits (since their are free
large storage email services this
matters less now) so deleting emails
that you downloaded was a must.
5. (for completeness - thanks Evan) POP
clients open a TCP/IP connection to
the server, authenticates itself,
asks for any email and does whatever
processing it needs, and then close
the connection. IMAP clients
generally keep one or more TCP/IP
sockets open with the server the
whole time they are running, taking
up those resources.
6. POP is a much simpler protocol to implement and can handle a greater number of clients with the same amount of resources. |
450,372 | i have a biztalk - window service tied middleware application which talks to other system.
recently we had a request to test for scenarios which relates to the date.
as we have a lot of places in the application which uses the .net Datetime.Now value, we don't really want to go into the code level and change all these values.
so we're looking at the simplest way to test which is to just change the OS time.
but what we notice is that sometimes when we change the system date time, we will get account lock out due to Active Directory.
1. So my question is what's a good and safe way that i can test for
future dates, etc by changing the windows OS system date time but
without causing any issues with the Active Directory.
2. And where can i find out more about AD and how it issues token and
what's the correlation with the system date time changes.
Thanks!
~m | 2012/11/20 | [
"https://serverfault.com/questions/450372",
"https://serverfault.com",
"https://serverfault.com/users/54419/"
] | Have you tried to put your php.ini under **/etc/php5/fpm/php.ini**? This is normally the default location that php reads from, if I understand php5-fpm correctly. | I have the same problem in Centos 7 I used nginx as the webserver. I restared php-fpm service and my problem solved. the reason is nginx use php-fpm service for handling php the only way to reflect your changes is restart php-fpm service.
you need to run **systemctl restart php-fpm** |
442 | This is a kind of question that a few people on the main site think is off topic for this question, but wasn't actually discussed in the definition phase (at least, I can find no such question there).
Is it really off-topic here? | 2010/07/14 | [
"https://gaming.meta.stackexchange.com/questions/442",
"https://gaming.meta.stackexchange.com",
"https://gaming.meta.stackexchange.com/users/23/"
] | I say that yes, **it should be off-topic**.
I mean, a question like "why does Team Fortress Classic has separate health and armor values" is closer to a valid question, in my opinion - an example answer is "to introduce a limited friendly-fire mechanism", or "to give more importance to the engineer".
But I feel that a general questions like "why do FPSs sometimes have separate health and armor values" is a lot more about general game design. There's a [separate Area51 proposal for game design and development](http://area51.stackexchange.com/proposals/2825/game-development).
Also see [another question here on gaming meta](https://gaming.meta.stackexchange.com/questions/226/what-should-our-faq-contain), where my FAQ proposal explicitly prohibits game design questions - although it's just a proposal, of course, it's not anything official. | In the most generic sense, I believe it is off-topic. General Game Design questions seem like they would be better suited for the Game Development SE, that will be entering private beta soonish.
If its about the underlying design of an existing game, I believe that it is well within the scope.
For example: [Which is better for Pikachu in Pokémon Red: Swift or Slash?](https://gaming.stackexchange.com/questions/1452/which-is-better-in-pokemon-red-swift-or-slash) |
442 | This is a kind of question that a few people on the main site think is off topic for this question, but wasn't actually discussed in the definition phase (at least, I can find no such question there).
Is it really off-topic here? | 2010/07/14 | [
"https://gaming.meta.stackexchange.com/questions/442",
"https://gaming.meta.stackexchange.com",
"https://gaming.meta.stackexchange.com/users/23/"
] | There needs to be a fine understanding about what is and what isn't a Game Design question. A game design question is one that is concerned about the development, implementation, and motivation behind a mechanic. As our site is geared towards gamers, whose main concern is how this mechanic affects the experience and not its creation, it is not really in our field of expertise. We can only guess what the developers were thinking of (those of us who aren't also game developers, at any rate).
A question about the mechanics of a game, in terms of the game world, is not a game design question. It's asking about what is happening in the game, as opposed to what is happening in the design of the game. For example, "How do effort values work in Pokemon" is not a game design question because its interest is in the gameplay aspect. Comparatively, "Why did they change from the type-attribute to the physical/special split" is a design question, because its interest is in the choices made in *creating* the game.
So as a good rule of thumb, think to yourself when it comes to a mechanics question, "Does this information concern me for my choices in playing the game?" versus "Does this information concern me in how the game was created?". The latter is off-topic, the former is on-topic. | In the most generic sense, I believe it is off-topic. General Game Design questions seem like they would be better suited for the Game Development SE, that will be entering private beta soonish.
If its about the underlying design of an existing game, I believe that it is well within the scope.
For example: [Which is better for Pikachu in Pokémon Red: Swift or Slash?](https://gaming.stackexchange.com/questions/1452/which-is-better-in-pokemon-red-swift-or-slash) |
442 | This is a kind of question that a few people on the main site think is off topic for this question, but wasn't actually discussed in the definition phase (at least, I can find no such question there).
Is it really off-topic here? | 2010/07/14 | [
"https://gaming.meta.stackexchange.com/questions/442",
"https://gaming.meta.stackexchange.com",
"https://gaming.meta.stackexchange.com/users/23/"
] | I say that yes, **it should be off-topic**.
I mean, a question like "why does Team Fortress Classic has separate health and armor values" is closer to a valid question, in my opinion - an example answer is "to introduce a limited friendly-fire mechanism", or "to give more importance to the engineer".
But I feel that a general questions like "why do FPSs sometimes have separate health and armor values" is a lot more about general game design. There's a [separate Area51 proposal for game design and development](http://area51.stackexchange.com/proposals/2825/game-development).
Also see [another question here on gaming meta](https://gaming.meta.stackexchange.com/questions/226/what-should-our-faq-contain), where my FAQ proposal explicitly prohibits game design questions - although it's just a proposal, of course, it's not anything official. | There needs to be a fine understanding about what is and what isn't a Game Design question. A game design question is one that is concerned about the development, implementation, and motivation behind a mechanic. As our site is geared towards gamers, whose main concern is how this mechanic affects the experience and not its creation, it is not really in our field of expertise. We can only guess what the developers were thinking of (those of us who aren't also game developers, at any rate).
A question about the mechanics of a game, in terms of the game world, is not a game design question. It's asking about what is happening in the game, as opposed to what is happening in the design of the game. For example, "How do effort values work in Pokemon" is not a game design question because its interest is in the gameplay aspect. Comparatively, "Why did they change from the type-attribute to the physical/special split" is a design question, because its interest is in the choices made in *creating* the game.
So as a good rule of thumb, think to yourself when it comes to a mechanics question, "Does this information concern me for my choices in playing the game?" versus "Does this information concern me in how the game was created?". The latter is off-topic, the former is on-topic. |
6,720 | My employer intends to purchase a laptop for me in the USA, then send it to me in South Africa. I've read that the GTX 10 series cards have desktop level performance even on laptops.
I've asked around, and Dell is really the only supplier that will support the laptop internationally.. i.e. I won't need to ship it all the way back to the USA if I need repairs.
I've looked at local suppliers that have MSI and ASUS laptops with GTX1080's too.. but they are very bulky and look like too much like gaming rigs (which they are). This new alienware range actually looks a little more conservative and they're slimmer than the other gaming rigs. Ultimately the looks don't matter though. It's just a small consideration.
Note: This isn't for gaming - it's for design work.. with a preference for fast render times in a laptop (I will be travelling a lot).
I've been looking at the Alienware 17 R4 laptop:
It's a 17inch UHD (3840 x 2160) IPS screen - so the color accuracy should be decent. It contains a GTX 1070 with 8GB GDDR5 Also it has: 7th Generation Intel® Core™ i7-7820HK (Quad-Core, 8MB Cache, Overclocking up to 4.4GHz )
There are 2 more expensive Alienware 17 configurations that have GTX 1080s, but they have TN panels.. so I'm leaning toward this IPS one. I intend to max out the RAM and take 3 years of Premium support and accident cover.. so the total cost comes to about $3100
So with that budget in mind.. there's also the whole precision line from Dell.
The New Precision 5520
It's 15inch UltraSharp UHD IGZO (3840x2160) Touch Wide View LED-backlit with PremiumPanel Guarantee - so I guess this might be an even better screen.
If I select specs like the highest end processor: Intel Core Xeon E3-1505M v6 (Quad Core Xeon 3.00GHz, 4.00GHz Turbo, 8MB 45W, w/Intel HD Graphics 630 32GB Ram, add the same HDD's as the alienware etc..
The price comes to 3,014.90 (so basically the same as Alienware)
The Graphics card difference would be that this has a Nvidia Quadro M1200 w/4GB GDDR5
So which of these 2 laptops do you think would render and work better in blender?
I don't do big complex scenes.. it's mostly simple product packaging and bottles.. some glass.. sometimes a simple area to display items like a table with light streaming in from a side window.. wooden surface sometimes. But nothing crazy. I do need to do A LOT of renders though.. so we need something snappy.
Thank you!! | 2017/01/25 | [
"https://hardwarerecs.stackexchange.com/questions/6720",
"https://hardwarerecs.stackexchange.com",
"https://hardwarerecs.stackexchange.com/users/5458/"
] | I think that the Alienware with the GTX 1070 is going to work better for your application. When considering the GPU options.
GTX 1070 vs Quadro M1200.
The GTX 1070 has 1920 CUDA cores vs. [640 CUDA cores from the Quadro M1200](https://www.reddit.com/r/nvidia/comments/5nt3ns/quadro_m1200/)
GTX 1070 is rated for 6.5 TFLOPS vs. 1.4 TFLOPS
---
In terms of benchmarks (these are the desktop versions, I can't find benchmarks for the m1200)
Passmark:
GTX 1070: 10,973
Quadro K1200: 2992
---
In conclusion, if you are looking for GPU power, the laptop with the GTX 1070 (Alienware) is going to be the better option, if you need professional driver support, then take the Quadro (Precision Workstation). I know there is driver [support for CUDA](https://blender.stackexchange.com/questions/60308/cycles-support-for-gtx-1070) 8.0 cards (in blender) so that isn't an issue. | Dell. In your build, select the option for SSD. My recommendation would not be for touchscreen just yet on the 15" screen because it isn't QUITE up to the level of larger displays used for rendering and image creation. Still keep the UHD screen though.
You mentioned traveling. The Alienware laptop weighs in at a full 10lbs whereas the Dell weighs in at 3.9 lbs. The 17" laptop isn't even close to ideal for traveling. That's really going to be the deciding factor here. |
6,720 | My employer intends to purchase a laptop for me in the USA, then send it to me in South Africa. I've read that the GTX 10 series cards have desktop level performance even on laptops.
I've asked around, and Dell is really the only supplier that will support the laptop internationally.. i.e. I won't need to ship it all the way back to the USA if I need repairs.
I've looked at local suppliers that have MSI and ASUS laptops with GTX1080's too.. but they are very bulky and look like too much like gaming rigs (which they are). This new alienware range actually looks a little more conservative and they're slimmer than the other gaming rigs. Ultimately the looks don't matter though. It's just a small consideration.
Note: This isn't for gaming - it's for design work.. with a preference for fast render times in a laptop (I will be travelling a lot).
I've been looking at the Alienware 17 R4 laptop:
It's a 17inch UHD (3840 x 2160) IPS screen - so the color accuracy should be decent. It contains a GTX 1070 with 8GB GDDR5 Also it has: 7th Generation Intel® Core™ i7-7820HK (Quad-Core, 8MB Cache, Overclocking up to 4.4GHz )
There are 2 more expensive Alienware 17 configurations that have GTX 1080s, but they have TN panels.. so I'm leaning toward this IPS one. I intend to max out the RAM and take 3 years of Premium support and accident cover.. so the total cost comes to about $3100
So with that budget in mind.. there's also the whole precision line from Dell.
The New Precision 5520
It's 15inch UltraSharp UHD IGZO (3840x2160) Touch Wide View LED-backlit with PremiumPanel Guarantee - so I guess this might be an even better screen.
If I select specs like the highest end processor: Intel Core Xeon E3-1505M v6 (Quad Core Xeon 3.00GHz, 4.00GHz Turbo, 8MB 45W, w/Intel HD Graphics 630 32GB Ram, add the same HDD's as the alienware etc..
The price comes to 3,014.90 (so basically the same as Alienware)
The Graphics card difference would be that this has a Nvidia Quadro M1200 w/4GB GDDR5
So which of these 2 laptops do you think would render and work better in blender?
I don't do big complex scenes.. it's mostly simple product packaging and bottles.. some glass.. sometimes a simple area to display items like a table with light streaming in from a side window.. wooden surface sometimes. But nothing crazy. I do need to do A LOT of renders though.. so we need something snappy.
Thank you!! | 2017/01/25 | [
"https://hardwarerecs.stackexchange.com/questions/6720",
"https://hardwarerecs.stackexchange.com",
"https://hardwarerecs.stackexchange.com/users/5458/"
] | I think that the Alienware with the GTX 1070 is going to work better for your application. When considering the GPU options.
GTX 1070 vs Quadro M1200.
The GTX 1070 has 1920 CUDA cores vs. [640 CUDA cores from the Quadro M1200](https://www.reddit.com/r/nvidia/comments/5nt3ns/quadro_m1200/)
GTX 1070 is rated for 6.5 TFLOPS vs. 1.4 TFLOPS
---
In terms of benchmarks (these are the desktop versions, I can't find benchmarks for the m1200)
Passmark:
GTX 1070: 10,973
Quadro K1200: 2992
---
In conclusion, if you are looking for GPU power, the laptop with the GTX 1070 (Alienware) is going to be the better option, if you need professional driver support, then take the Quadro (Precision Workstation). I know there is driver [support for CUDA](https://blender.stackexchange.com/questions/60308/cycles-support-for-gtx-1070) 8.0 cards (in blender) so that isn't an issue. | Just to get a level of comparison:
The professional (workstation) videocards in the Nvidia family have usually the 1000 / 2000 / 3000 / 4000 / 5000 numbers, prefixed by the generation letter. They correspond to X40 / X50 / X60 / X70 / X80 of the consummer editions.
So, for example, M5000M is roughly equivalent of the 980M.
Following the same logic, the newer Nvidia GTX 1070 will have as equivalent Nvidia Quadro P4000M.
But from the 9xx line to the 10xx line the jump was fantastic. For example 1060 is a something between the previous 970 and 980, while taking less power.
So what you are comparing here (M1200) to GTX 1070M is like comparing 1040 to 1070. You say what? There's no GTX 1040? Yes, you're right, that's how low that video card is.
You simply cannot compare them. So, if what you need is video processing power, there's no question. |
3,778,947 | I'm using JasperReporting engine, and i need to optimize reporting performance. Currently my application compiles reports from \*.jrxml files every time, as I'm not changing the reports now and app is not able to generate user-defined reports I should compile them once and use .jasper files in future..... AM I RIGHT?? And do I need to re-compile them?
Thanks in advance! | 2010/09/23 | [
"https://Stackoverflow.com/questions/3778947",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/445190/"
] | AutoPostBack set to true will initiate a page postback (like clicking a button) whenever a server event for the control is fired. Server-side code tied to initiated control events will happen immediately (along with a full/partial page load).
AutoPostBack set to false will NOT initiate this and event code will not fire until another "posting-back" event fires. | A simple google would have told you the answer to this:
Robbed from here as I thought someone else would be able to explain this better than me.
<http://www.asp101.com/samples/autopostback_aspx.asp>
>
> AutoPostBack is built into the
> form-based server controls, and when
> enabled, automatically posts the page
> back to the server whenever the value
> of the control in question is changed.
> Because of the additional server
> requests it causes, it's not something
> you'll want to enable for all your
> controls, but for things that affect
> page display or change choices further
> down the form, it can be really handy.
> Not to mention the fact that it will
> save you a lot of time and headaches
> over trying to implement something
> similar on your own. Not that it's
> really all that complex to do on your
> own if you're good with javascript,
> but it's hard to get any simpler then
> just setting AutoPostBack="True"
>
>
>
One thing to point out, this will only work when javascript is enabled, in the absense of javascript you will need to provide another mechanism to envoke the postback. |
27,991 | I can't stay in house much more this winter I need to go on longer hikes.
I am used to longer hikes up to 14 days, but not during the winter. I want to do 1-5 day hikes in winter in dry weather, temperatures: - 12C(10F) to +5C(41F). The temperatues will be mostly 0 to -5 degrees Celsuis. There will be snow of course and I will have to use snowshoes from time to time,...
Now for 1 day winter hikes I use multi layers with soft shell on top, depends,.. I don't know if I should buy light down jacket, or a polyester one? I have no idea how down jackets keep up in case snow keeps falling from trees(does down get wet?) on you and jacket and how much do down jackets get wet from sweating? They say if down gets wet it is not good, but don't know what to expect in my case. I will carry up till 13 kg backpack. I don't know how much do these light down jackets handle weight and shoulder straps in practice?
What do you think, what are your experiences? | 2021/12/13 | [
"https://outdoors.stackexchange.com/questions/27991",
"https://outdoors.stackexchange.com",
"https://outdoors.stackexchange.com/users/22280/"
] | Down has worked well for me. My experience includes fall hiking at medium altitudes (10,000 to 12,000 feet), hence snow on the ground and snow falling. I've always had a down jacket with a water repellent outer surface, plus a water-proof poncho for rain or wet-snow conditions. The heavier and/or wetter the snow, the more often you have to brush the snow off your jacket, but moisture from snow has not soaked through the water-repellent surface plus poncho. The down itself has not got wet, or at least not damp enough to notice any lessening of insulation.
Caveat: My experience is fall, not winter, and where I hike there is rarely more than two consecutive days with snow or rain, and without sun in the fall.
I am sensitive to cold, and no fleece, even with multiple layers underneath, has ever been warm enough for me at the lower end of your temperature range, especially if there is wind.
You have more to fear at the upper end of your range, where there could be wet snow or even rain or some unholy mixture of the two. Thus, a good poncho is a must.
Your under-layers should absorb your sweat, and if they don't, take off something, either the jacket or one of your underlayers.
As for abrasion of the straps on the jacket, It hasn't happened to me, but I have always had a sturdy jacket. And, with a light pack (you say 13 kg), you might be able to wear the pack under your jacket if the jacket is loose; I have done that to keep a day-hiker dry.
Good hiking and banish that cabin fever!! | My experience is in the UK. Your problem isn't the -5, it's the 0. Once the temperature freezes and stays there, all the humidity drops out of the air. Above or close to zero, you've got general dampness to deal with, and down becomes much less effective when it's damp. If you're doing multi-day hikes where there isn't an opportunity to dry clothes overnight, this is a real problem, because *everything* gets damp.
Also on that note, get yourself off the tent floor as far as you can. Z-Rest type pads are great for this, because airflow under the pad helps to stop the tent floor getting damp. |
34,446 | As most crashes are on takeoff and landing, and fire is the real killer, most often. Why not have breakaway wings? That's where the gas is. Let's assume a plane has to make a hard landing..upon touchdown/contact jettison the wings. They serve no purpose at that point and they definitely kill people. Breakaway parts/modules are employed in many arenas, so why not wings? | 2017/01/07 | [
"https://aviation.stackexchange.com/questions/34446",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/19040/"
] | I can't think of an accident scenario where this might help. If you're hitting the ground hard enough to crash but have survivors, you're looking at an accident like [TK 1951](https://en.m.wikipedia.org/wiki/Turkish_Airlines_Flight_1951), where not only was the wreckage all in pretty much the same area, but it didn't even catch on fire. Aviation fuel is not as volatile as movies make it seem.
Maybe you are thinking of something like [AF 358](https://en.m.wikipedia.org/wiki/Air_France_Flight_358) which overran the end of the runway and burst into flames? Despite that fire everyone survived, but what if they realised it was going to overrun and jettisoned the wings whilst still on the runway?
Well the biggest problem to me is how to slow the aircraft down without wings. At higher speeds, the wheel brakes are ineffective without the use of ground spoilers. Without the reverse thrust from the engines you are guaranteeing that the aircraft will be going faster when it leaves the runway, leading to a much higher chance of casualties.
No piece of engineering is perfect either - what happens when it fails and the wings accidentally detach when everything is going well? What if they are flying in severe turbulence and the sensors detect high G forces and confuses that for a hard landing? Or if it a manual jettison, what if the pilots accidentally pull it, or a suicidal pilot does it while the other is looking the other way?
There are many other problems too, such as how some aircraft are designed with the gear support in the wings, that some have large fuel tanks in the fuselage, and the extra weight and cost of getting such a system certified. Ultimately this suggestion falls into the same bucket as every other drastic safety idea - in trying to fix a problem that barely exists, it creates a lot more in its place. | The early 310s with "tuna tanks" were designed with exactly this scenario in mind. The idea was that the tanks would keep the fuel as far from the cabin as possible and [shear off](https://www.aopa.org/go-fly/aircraft-and-ownership/aircraft-fact-sheets/cessna-310) in a crash. Cessna abandoned this idea some years later when they incorporated aux tanks into the wings (310L) and then later into the nacelles (310N).
I do not know if data exists to quantify the effectiveness of this design feature. |
34,446 | As most crashes are on takeoff and landing, and fire is the real killer, most often. Why not have breakaway wings? That's where the gas is. Let's assume a plane has to make a hard landing..upon touchdown/contact jettison the wings. They serve no purpose at that point and they definitely kill people. Breakaway parts/modules are employed in many arenas, so why not wings? | 2017/01/07 | [
"https://aviation.stackexchange.com/questions/34446",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/19040/"
] | "It's not complicated."
As with most things in aerospace engineering, it is actually a lot more complicated than someone not familiar with aircraft design might think. There are a number of reasons why this isn't done:
### Wing Spars
Wings have to be *really* strong. They literally bear (almost) the entire weight of the aircraft in normal 1 G flight and multiples of the weight of the aircraft when maneuvering. For example, in a 60 degree bank while maintaining altitude, the load on the wings is *twice* the weight of the aircraft. Of course, airliners don't normally do 60 degree banks, but they're designed to be able to withstand loads much higher than what they would normally experience on a routine flight.
In order to keep the wings from separating from the aircraft under such loads, they're designed with a single, very strong structure called a [wing spar](https://en.wikipedia.org/wiki/Spar_(aeronautics)) that runs most or all of the wing span. This is not one spar per wing, but rather a single spar that runs from one wingtip, through the fuselage, to the other wingtip. This spar is responsible for holding up the weight of the fuselage during flight and the weight of the wings (and, depending on where the gear is located, possibly also the fuselage) while on the ground. Using a single structure running the entire span for the spar is the safest and most efficient way to bear the needed loads, as it removes any connections that would otherwise be possible points of failure.
By design, the spar is *really hard to break*. Separating the wings from the aircraft would require breaking the spar. This would require enormous amounts of force and/or heat. The systems to supply that force and/or heat would be heavy and also, by design, rather dangerous. Neither of these is a good thing for an airplane.
[](https://i.stack.imgur.com/qtTYB.jpg)
**Main spar of a de Havilland DH.60 Moth** Source: [Wikipedia](https://commons.wikimedia.org/wiki/File:DH-60_Gipsy_Moth_Wing_Structure.JPG)
### Landing Roll
It turns out that the wings (especially of an airliner) are actually more useful than you might think during the landing roll.
During a landing, the primary methods of slowing down are wheel brakes, engine reverse thrust, and aerodynamic drag. All three of these, at least to some extent, depend on the wings being attached to the aircraft. The engines, flaps, and spoilers are all usually mounted to the wings. The wing flaps and spoilers aid in providing large amounts of aerodynamic drag during the landing roll. The engines also require fuel flow and, as you've noted, that usually comes primarily from the wing. The wheel brakes might have some effect without the wings, but it would be greatly diminished. Braking action requires weight on the wheels. A lot of this weight comes from the weight of the wing structures and more comes from the downward aerodynamic forces provided by the spoilers.
### Attitude Control
During the landing roll, the wings are still aiding quite a bit in controlling the attitude of the aircraft. In particular, the ailerons are still effective during the high-speed parts of the landing roll and are used during that time to keep the aircraft level in the roll axis. Additionally, a tall and very long tricycle, by itself, isn't a terribly stable vehicle. Especially at high speeds, it would be more prone to tipping over without the wings attached.
### Landing Gear
Take a look at the main landing gear on these aircraft:
[](https://i.stack.imgur.com/yhiNw.jpg)
**Boeing 777** Source: [Wikipedia](https://en.wikipedia.org/wiki/Boeing_777#/media/File:EHAM_19-05-2010_247_(4622220101).jpg)
[](https://i.stack.imgur.com/VvrWR.jpg)
**Boeing 757** Source: [Wikipedia](https://en.wikipedia.org/wiki/Boeing_757#/media/File:Transavia_Airlines_Boeing_757-2K2_Wedelstaedt.jpg)
[](https://i.stack.imgur.com/SUQL3.jpg)
**Boeing 737** Source: [Wikipedia](https://en.wikipedia.org/wiki/Boeing_737#/media/File:Lufthansa-1.jpg)
[](https://i.stack.imgur.com/4d0Lr.jpg)
**Airbus A330** Source: [Wikipedia](https://en.wikipedia.org/wiki/Airbus_A330#/media/File:Air_China_Airbus_A330-243_B-6075_MUC_2015_01.jpg)
As you will notice in all of these pictures, the main landing gear are *attached to the wings*.
It's very common in aircraft design for the main landing gear to be attached to the wings. This makes sense as the wing root is structurally a good place from which to support the weight of the aircraft and also happens to provide a nice, wide wheel base to keep the aircraft more stable on the ground.
If the wing separates from the aircraft at touchdown, the main landing gear goes with the wings. As you can imagine, this creates lots of problems for a landing roll. In addition to the loss of wheel brakes, you are now skidding down the runway on the bottom of the fuselage instead of rolling down it on wheels. Hopefully I don't need to go into the reasons why this is not considered to be desirable.
### Risk of Failure
Any system can fail. If one of these systems accidentally activated (either by accidental command from the flight deck or by failure of the system,) losing one's wings while in flight is a rather bad outcome. Given that flights needing wings are extremely common and flights crash landing in such a way that jettisoning the fuel tanks would be desirable are extremely uncommon, having such a system around is probably more likely to kill someone than save someone.
### Burning Fuel
While one might think that jet fuel is easy to burn, it actually turns out that it isn't. In fact, it's rather difficult to ignite it. This is intentional in order to minimize the chance of the fuel igniting during an accident. Even in the rather violent crash of [Asiana 214](https://en.wikipedia.org/wiki/Asiana_Airlines_Flight_214) and the large post-crash fire, [the fuel never ignited](https://www.ntsb.gov/investigations/AccidentReports/Reports/AAR1401.pdf) (see first paragraph of page 37.) So, the risk being mitigated here might not actually be as large as one might think.
Note, however, that avgas (used commonly in light, piston-engine aircraft) is quite different from jet fuel. Avgas is similar to normal car gasoline and will burn rather easily.
### Cost/Benefit Ratio
As previously mentioned, a system capable of quickly breaking the main wing spar would be heavy. It would be expensive to design to be safe. It would be expensive to build it. It would also be expensive to carry all of that extra weight around on millions upon millions of flights per year. All of this cost and added safety risk is not deemed to be worthwhile to provide a system that is rather unlikely to ever be useful. | The early 310s with "tuna tanks" were designed with exactly this scenario in mind. The idea was that the tanks would keep the fuel as far from the cabin as possible and [shear off](https://www.aopa.org/go-fly/aircraft-and-ownership/aircraft-fact-sheets/cessna-310) in a crash. Cessna abandoned this idea some years later when they incorporated aux tanks into the wings (310L) and then later into the nacelles (310N).
I do not know if data exists to quantify the effectiveness of this design feature. |
34,446 | As most crashes are on takeoff and landing, and fire is the real killer, most often. Why not have breakaway wings? That's where the gas is. Let's assume a plane has to make a hard landing..upon touchdown/contact jettison the wings. They serve no purpose at that point and they definitely kill people. Breakaway parts/modules are employed in many arenas, so why not wings? | 2017/01/07 | [
"https://aviation.stackexchange.com/questions/34446",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/19040/"
] | Just wanted to add that if wings were to be 'disengaged' when needed/emergency-case, the aeroplane-fuselage or a 'metal Tube' now will fall faster than a human would free fall, there will be nothing to slow it down (assuming pilot/autoPilot can still control wing-control-surfaces or whatever its called).
If the aeroplane is very close to ground or on ground and moving, discarding the wings now means throwing them away with undercarriage, the wings would most likely tumble and continue to move with the plane and may be even into it.
But if the aeroplane is on ground and not moving and then the wings are disconnected, means the Plane still has wings next to it, but now the fuselage is below it. The fuselage could roll and make it difficult to evacuate.
Also, lot of aviation fuel (30% or more) is in Central tank + ACT. i.e. in fuselage. | The early 310s with "tuna tanks" were designed with exactly this scenario in mind. The idea was that the tanks would keep the fuel as far from the cabin as possible and [shear off](https://www.aopa.org/go-fly/aircraft-and-ownership/aircraft-fact-sheets/cessna-310) in a crash. Cessna abandoned this idea some years later when they incorporated aux tanks into the wings (310L) and then later into the nacelles (310N).
I do not know if data exists to quantify the effectiveness of this design feature. |
34,446 | As most crashes are on takeoff and landing, and fire is the real killer, most often. Why not have breakaway wings? That's where the gas is. Let's assume a plane has to make a hard landing..upon touchdown/contact jettison the wings. They serve no purpose at that point and they definitely kill people. Breakaway parts/modules are employed in many arenas, so why not wings? | 2017/01/07 | [
"https://aviation.stackexchange.com/questions/34446",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/19040/"
] | I can't think of an accident scenario where this might help. If you're hitting the ground hard enough to crash but have survivors, you're looking at an accident like [TK 1951](https://en.m.wikipedia.org/wiki/Turkish_Airlines_Flight_1951), where not only was the wreckage all in pretty much the same area, but it didn't even catch on fire. Aviation fuel is not as volatile as movies make it seem.
Maybe you are thinking of something like [AF 358](https://en.m.wikipedia.org/wiki/Air_France_Flight_358) which overran the end of the runway and burst into flames? Despite that fire everyone survived, but what if they realised it was going to overrun and jettisoned the wings whilst still on the runway?
Well the biggest problem to me is how to slow the aircraft down without wings. At higher speeds, the wheel brakes are ineffective without the use of ground spoilers. Without the reverse thrust from the engines you are guaranteeing that the aircraft will be going faster when it leaves the runway, leading to a much higher chance of casualties.
No piece of engineering is perfect either - what happens when it fails and the wings accidentally detach when everything is going well? What if they are flying in severe turbulence and the sensors detect high G forces and confuses that for a hard landing? Or if it a manual jettison, what if the pilots accidentally pull it, or a suicidal pilot does it while the other is looking the other way?
There are many other problems too, such as how some aircraft are designed with the gear support in the wings, that some have large fuel tanks in the fuselage, and the extra weight and cost of getting such a system certified. Ultimately this suggestion falls into the same bucket as every other drastic safety idea - in trying to fix a problem that barely exists, it creates a lot more in its place. | Just wanted to add that if wings were to be 'disengaged' when needed/emergency-case, the aeroplane-fuselage or a 'metal Tube' now will fall faster than a human would free fall, there will be nothing to slow it down (assuming pilot/autoPilot can still control wing-control-surfaces or whatever its called).
If the aeroplane is very close to ground or on ground and moving, discarding the wings now means throwing them away with undercarriage, the wings would most likely tumble and continue to move with the plane and may be even into it.
But if the aeroplane is on ground and not moving and then the wings are disconnected, means the Plane still has wings next to it, but now the fuselage is below it. The fuselage could roll and make it difficult to evacuate.
Also, lot of aviation fuel (30% or more) is in Central tank + ACT. i.e. in fuselage. |
34,446 | As most crashes are on takeoff and landing, and fire is the real killer, most often. Why not have breakaway wings? That's where the gas is. Let's assume a plane has to make a hard landing..upon touchdown/contact jettison the wings. They serve no purpose at that point and they definitely kill people. Breakaway parts/modules are employed in many arenas, so why not wings? | 2017/01/07 | [
"https://aviation.stackexchange.com/questions/34446",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/19040/"
] | "It's not complicated."
As with most things in aerospace engineering, it is actually a lot more complicated than someone not familiar with aircraft design might think. There are a number of reasons why this isn't done:
### Wing Spars
Wings have to be *really* strong. They literally bear (almost) the entire weight of the aircraft in normal 1 G flight and multiples of the weight of the aircraft when maneuvering. For example, in a 60 degree bank while maintaining altitude, the load on the wings is *twice* the weight of the aircraft. Of course, airliners don't normally do 60 degree banks, but they're designed to be able to withstand loads much higher than what they would normally experience on a routine flight.
In order to keep the wings from separating from the aircraft under such loads, they're designed with a single, very strong structure called a [wing spar](https://en.wikipedia.org/wiki/Spar_(aeronautics)) that runs most or all of the wing span. This is not one spar per wing, but rather a single spar that runs from one wingtip, through the fuselage, to the other wingtip. This spar is responsible for holding up the weight of the fuselage during flight and the weight of the wings (and, depending on where the gear is located, possibly also the fuselage) while on the ground. Using a single structure running the entire span for the spar is the safest and most efficient way to bear the needed loads, as it removes any connections that would otherwise be possible points of failure.
By design, the spar is *really hard to break*. Separating the wings from the aircraft would require breaking the spar. This would require enormous amounts of force and/or heat. The systems to supply that force and/or heat would be heavy and also, by design, rather dangerous. Neither of these is a good thing for an airplane.
[](https://i.stack.imgur.com/qtTYB.jpg)
**Main spar of a de Havilland DH.60 Moth** Source: [Wikipedia](https://commons.wikimedia.org/wiki/File:DH-60_Gipsy_Moth_Wing_Structure.JPG)
### Landing Roll
It turns out that the wings (especially of an airliner) are actually more useful than you might think during the landing roll.
During a landing, the primary methods of slowing down are wheel brakes, engine reverse thrust, and aerodynamic drag. All three of these, at least to some extent, depend on the wings being attached to the aircraft. The engines, flaps, and spoilers are all usually mounted to the wings. The wing flaps and spoilers aid in providing large amounts of aerodynamic drag during the landing roll. The engines also require fuel flow and, as you've noted, that usually comes primarily from the wing. The wheel brakes might have some effect without the wings, but it would be greatly diminished. Braking action requires weight on the wheels. A lot of this weight comes from the weight of the wing structures and more comes from the downward aerodynamic forces provided by the spoilers.
### Attitude Control
During the landing roll, the wings are still aiding quite a bit in controlling the attitude of the aircraft. In particular, the ailerons are still effective during the high-speed parts of the landing roll and are used during that time to keep the aircraft level in the roll axis. Additionally, a tall and very long tricycle, by itself, isn't a terribly stable vehicle. Especially at high speeds, it would be more prone to tipping over without the wings attached.
### Landing Gear
Take a look at the main landing gear on these aircraft:
[](https://i.stack.imgur.com/yhiNw.jpg)
**Boeing 777** Source: [Wikipedia](https://en.wikipedia.org/wiki/Boeing_777#/media/File:EHAM_19-05-2010_247_(4622220101).jpg)
[](https://i.stack.imgur.com/VvrWR.jpg)
**Boeing 757** Source: [Wikipedia](https://en.wikipedia.org/wiki/Boeing_757#/media/File:Transavia_Airlines_Boeing_757-2K2_Wedelstaedt.jpg)
[](https://i.stack.imgur.com/SUQL3.jpg)
**Boeing 737** Source: [Wikipedia](https://en.wikipedia.org/wiki/Boeing_737#/media/File:Lufthansa-1.jpg)
[](https://i.stack.imgur.com/4d0Lr.jpg)
**Airbus A330** Source: [Wikipedia](https://en.wikipedia.org/wiki/Airbus_A330#/media/File:Air_China_Airbus_A330-243_B-6075_MUC_2015_01.jpg)
As you will notice in all of these pictures, the main landing gear are *attached to the wings*.
It's very common in aircraft design for the main landing gear to be attached to the wings. This makes sense as the wing root is structurally a good place from which to support the weight of the aircraft and also happens to provide a nice, wide wheel base to keep the aircraft more stable on the ground.
If the wing separates from the aircraft at touchdown, the main landing gear goes with the wings. As you can imagine, this creates lots of problems for a landing roll. In addition to the loss of wheel brakes, you are now skidding down the runway on the bottom of the fuselage instead of rolling down it on wheels. Hopefully I don't need to go into the reasons why this is not considered to be desirable.
### Risk of Failure
Any system can fail. If one of these systems accidentally activated (either by accidental command from the flight deck or by failure of the system,) losing one's wings while in flight is a rather bad outcome. Given that flights needing wings are extremely common and flights crash landing in such a way that jettisoning the fuel tanks would be desirable are extremely uncommon, having such a system around is probably more likely to kill someone than save someone.
### Burning Fuel
While one might think that jet fuel is easy to burn, it actually turns out that it isn't. In fact, it's rather difficult to ignite it. This is intentional in order to minimize the chance of the fuel igniting during an accident. Even in the rather violent crash of [Asiana 214](https://en.wikipedia.org/wiki/Asiana_Airlines_Flight_214) and the large post-crash fire, [the fuel never ignited](https://www.ntsb.gov/investigations/AccidentReports/Reports/AAR1401.pdf) (see first paragraph of page 37.) So, the risk being mitigated here might not actually be as large as one might think.
Note, however, that avgas (used commonly in light, piston-engine aircraft) is quite different from jet fuel. Avgas is similar to normal car gasoline and will burn rather easily.
### Cost/Benefit Ratio
As previously mentioned, a system capable of quickly breaking the main wing spar would be heavy. It would be expensive to design to be safe. It would be expensive to build it. It would also be expensive to carry all of that extra weight around on millions upon millions of flights per year. All of this cost and added safety risk is not deemed to be worthwhile to provide a system that is rather unlikely to ever be useful. | Just wanted to add that if wings were to be 'disengaged' when needed/emergency-case, the aeroplane-fuselage or a 'metal Tube' now will fall faster than a human would free fall, there will be nothing to slow it down (assuming pilot/autoPilot can still control wing-control-surfaces or whatever its called).
If the aeroplane is very close to ground or on ground and moving, discarding the wings now means throwing them away with undercarriage, the wings would most likely tumble and continue to move with the plane and may be even into it.
But if the aeroplane is on ground and not moving and then the wings are disconnected, means the Plane still has wings next to it, but now the fuselage is below it. The fuselage could roll and make it difficult to evacuate.
Also, lot of aviation fuel (30% or more) is in Central tank + ACT. i.e. in fuselage. |
143,455 | Some days ago, the spam protection was turned up a notch.
Unfortunately, it overshot the target by far. Now, as soon as I make two edits in close succession (which happens *often* – I’m sloppy), I am presented with a “human verification” and a **totally unreadable captcha.** It takes an average of five reloads to get a marginally readable one, and even then I’m guessing (and sometimes guessing wrong).
Please tune down the filter, or at least switch to a readable captcha.
In fact, wasn’t there previously a rule that once contributors had enough reputation, they’d be trusted not to be bots? Did that get switched off or am I remembering this wrong? | 2012/08/14 | [
"https://meta.stackexchange.com/questions/143455",
"https://meta.stackexchange.com",
"https://meta.stackexchange.com/users/1968/"
] | >
> Some days ago, the spam protection was turned up a notch.
>
>
>
[Well, actually](http://tirania.org/blog/archive/2011/Feb-17.html), it was *repaired*. Two weeks ago, we found a bug that for a long time prevented edits from being throttled *at all* (except for very narrow exceptions).
For the record, I posted this in our internal chat room:
Thanks for proving me right :)
In all seriousness: The throttling was fixed to do what it was supposed to do all along, and not technically turned up a notch. I'm well aware that this doesn't really make a difference to the user; I'm just explaining what was going on.
>
> and a **totally unreadable captcha.**
>
>
>
Yes, this is a problem. Both [Meta](https://meta.stackoverflow.com/search?q=recaptcha+hard+difficult) and the [general internet](http://www.google.com/search?q=recaptcha+hard+difficult+unreadable&tbs=qdr:y) are overflowing with complaints that many reCAPTCHAs have become close to unsolvable recently. This is something we have to tackle one way the other.
>
> In fact, wasn’t there previously a rule that once contributors had enough reputation, they’d be trusted not to be bots? Did that get switched off or am I remembering this wrong?
>
>
>
You are remembering correctly, for the most part. 10k users are only throttled to 10 seconds per edit (unlike the 30 seconds for lower-rep users).
**Update.** We have been heavily discussing this issue internally recently, and we all agree that the current state of affairs sucks big-time. Ideally a human being would never see a captcha, and if they get one after all, it should be reasonably solvable. We're discussing several routes to go, but the bottom line is that our throttling/bot detection needs to become smarter.
For the time being, we've made a change that should at least heavily reduce this issue in the particular case discussed here (submission of edits). It should now\* be close to impossible for a 10k user and much less probable than now for a <10k user to hit this throttle during normal operation.
This is certainly not the end of it, merely a step, but I hope you agree it's the right direction.
\*next build | I honestly think that the only problem the editing system *might* be bringing to Stackoverflow is large-scale vandalism. When it comes to that, I believe there are three attack sources
1. Anonymous users
2. 2k- rep users
3. 2k+ rep users
The review system already tackles the first two. I personally think that it's highly unlikely that a spammer would train robot accounts until they have 2k rep so they can bypass the review system (think how hard it was to get your first 2k rep)
That's why I think that **5 seconds** is a very decent waiting time between edits and when you're gonna show some CAPTCHAs, why not a user-friendly one like [SolveMedia](http://www.solvemedia.com)
**Edit:** Don't get me wrong, I'm all for stopping spammers and whatnots. But do we (You, Stackoverflow) need to nuke the house just get rid of cockroaches?
**Edit 2:** @nhahtdh's scenario is a perfect example of when a CAPTCHA should be deployed, when there's a *suspicious* behavior.
The key here is gradually escalating the measurements:
* 10 edit in 1 minute on different posts => suspicious => introduce CAPTCHA
* Same user did it again? Introduce CAPTCHA & Inform a moderator.
* Same user did it AGAIN? Suspend editing privileges.
In this case, you didn't annoy legit users AND minimized the damage of the **2k rep user** (and I don't think this will happen a lot).
Note: It took me 6 CAPTCHA retries to make this edit. |
143,455 | Some days ago, the spam protection was turned up a notch.
Unfortunately, it overshot the target by far. Now, as soon as I make two edits in close succession (which happens *often* – I’m sloppy), I am presented with a “human verification” and a **totally unreadable captcha.** It takes an average of five reloads to get a marginally readable one, and even then I’m guessing (and sometimes guessing wrong).
Please tune down the filter, or at least switch to a readable captcha.
In fact, wasn’t there previously a rule that once contributors had enough reputation, they’d be trusted not to be bots? Did that get switched off or am I remembering this wrong? | 2012/08/14 | [
"https://meta.stackexchange.com/questions/143455",
"https://meta.stackexchange.com",
"https://meta.stackexchange.com/users/1968/"
] | Over almost ***four years*** on Stack Overflow, Konrad has earned almost ***150k rep***. A highly committed Stack Overflow citizen, with ***2.5k answers*** and a mere 60 questions, he's one of those users that made Stack Overflow famous. He has ***40(!) accounts*** across Stack Exchange, eight of which sport ***>1k rep***. He is ***a moderator*** on one site.
Is anybody *really and seriously* trying to tell me ***nagging such a user with CAPTCHAs*** is doing the Stack Exchange network a favor? | The throttling should be changed in case somebody makes a typo and needs to make a quick edit.
Instead of no two edit should be within 10 seconds, the logic should be, **no more than 2 edits every 20 seconds** for example.
This means that 2 edits can be 1 second apart, as long as you do not have a 3rd edit, when the 1st edit was within 20 seconds ago.
For example, edits at 0 seconds, 1 seconds, 19 seconds should trigger a captcha.
Edits at 0 seconds, 1 seconds, 21 seconds should not trigger a captcha.
This would avoid 90% of the annoying captchas. |
143,455 | Some days ago, the spam protection was turned up a notch.
Unfortunately, it overshot the target by far. Now, as soon as I make two edits in close succession (which happens *often* – I’m sloppy), I am presented with a “human verification” and a **totally unreadable captcha.** It takes an average of five reloads to get a marginally readable one, and even then I’m guessing (and sometimes guessing wrong).
Please tune down the filter, or at least switch to a readable captcha.
In fact, wasn’t there previously a rule that once contributors had enough reputation, they’d be trusted not to be bots? Did that get switched off or am I remembering this wrong? | 2012/08/14 | [
"https://meta.stackexchange.com/questions/143455",
"https://meta.stackexchange.com",
"https://meta.stackexchange.com/users/1968/"
] | >
> Some days ago, the spam protection was turned up a notch.
>
>
>
[Well, actually](http://tirania.org/blog/archive/2011/Feb-17.html), it was *repaired*. Two weeks ago, we found a bug that for a long time prevented edits from being throttled *at all* (except for very narrow exceptions).
For the record, I posted this in our internal chat room:
Thanks for proving me right :)
In all seriousness: The throttling was fixed to do what it was supposed to do all along, and not technically turned up a notch. I'm well aware that this doesn't really make a difference to the user; I'm just explaining what was going on.
>
> and a **totally unreadable captcha.**
>
>
>
Yes, this is a problem. Both [Meta](https://meta.stackoverflow.com/search?q=recaptcha+hard+difficult) and the [general internet](http://www.google.com/search?q=recaptcha+hard+difficult+unreadable&tbs=qdr:y) are overflowing with complaints that many reCAPTCHAs have become close to unsolvable recently. This is something we have to tackle one way the other.
>
> In fact, wasn’t there previously a rule that once contributors had enough reputation, they’d be trusted not to be bots? Did that get switched off or am I remembering this wrong?
>
>
>
You are remembering correctly, for the most part. 10k users are only throttled to 10 seconds per edit (unlike the 30 seconds for lower-rep users).
**Update.** We have been heavily discussing this issue internally recently, and we all agree that the current state of affairs sucks big-time. Ideally a human being would never see a captcha, and if they get one after all, it should be reasonably solvable. We're discussing several routes to go, but the bottom line is that our throttling/bot detection needs to become smarter.
For the time being, we've made a change that should at least heavily reduce this issue in the particular case discussed here (submission of edits). It should now\* be close to impossible for a 10k user and much less probable than now for a <10k user to hit this throttle during normal operation.
This is certainly not the end of it, merely a step, but I hope you agree it's the right direction.
\*next build | Google announced today that they've made reCAPTCHAs considerably easier to read. [But *only* if you're not a robot](http://googleonlinesecurity.blogspot.com/2013/10/recaptcha-just-got-easier-but-only-if.html):
>
> As part of this, we’ve recently released an update that creates different classes of CAPTCHAs for different kinds of users. This multi-faceted approach allows us to determine whether a potential user is actually a human or not, and serve our legitimate users CAPTCHAs that most of them will find easy to solve. Bots, on the other hand, will see CAPTCHAs that are considerably more difficult and designed to stop them from getting through.
>
>
>
You can [test this out](https://stackoverflow.com/captcha) of you want. Here's the CAPTCHA I got:
That was so easy, I even bothered to fill in the alt text on that image! And if you happen to be using a keyboard with a separate pad for numbers, you should find this even easier (I'm typing this on my laptop while standing up).
Given how well the new human-biased system works, I'm marking this status-completed.
Of course, if you were lying and *are* indeed a robot, you should probably not be happy about this. |
143,455 | Some days ago, the spam protection was turned up a notch.
Unfortunately, it overshot the target by far. Now, as soon as I make two edits in close succession (which happens *often* – I’m sloppy), I am presented with a “human verification” and a **totally unreadable captcha.** It takes an average of five reloads to get a marginally readable one, and even then I’m guessing (and sometimes guessing wrong).
Please tune down the filter, or at least switch to a readable captcha.
In fact, wasn’t there previously a rule that once contributors had enough reputation, they’d be trusted not to be bots? Did that get switched off or am I remembering this wrong? | 2012/08/14 | [
"https://meta.stackexchange.com/questions/143455",
"https://meta.stackexchange.com",
"https://meta.stackexchange.com/users/1968/"
] | The throttling should be changed in case somebody makes a typo and needs to make a quick edit.
Instead of no two edit should be within 10 seconds, the logic should be, **no more than 2 edits every 20 seconds** for example.
This means that 2 edits can be 1 second apart, as long as you do not have a 3rd edit, when the 1st edit was within 20 seconds ago.
For example, edits at 0 seconds, 1 seconds, 19 seconds should trigger a captcha.
Edits at 0 seconds, 1 seconds, 21 seconds should not trigger a captcha.
This would avoid 90% of the annoying captchas. | Google announced today that they've made reCAPTCHAs considerably easier to read. [But *only* if you're not a robot](http://googleonlinesecurity.blogspot.com/2013/10/recaptcha-just-got-easier-but-only-if.html):
>
> As part of this, we’ve recently released an update that creates different classes of CAPTCHAs for different kinds of users. This multi-faceted approach allows us to determine whether a potential user is actually a human or not, and serve our legitimate users CAPTCHAs that most of them will find easy to solve. Bots, on the other hand, will see CAPTCHAs that are considerably more difficult and designed to stop them from getting through.
>
>
>
You can [test this out](https://stackoverflow.com/captcha) of you want. Here's the CAPTCHA I got:
That was so easy, I even bothered to fill in the alt text on that image! And if you happen to be using a keyboard with a separate pad for numbers, you should find this even easier (I'm typing this on my laptop while standing up).
Given how well the new human-biased system works, I'm marking this status-completed.
Of course, if you were lying and *are* indeed a robot, you should probably not be happy about this. |
143,455 | Some days ago, the spam protection was turned up a notch.
Unfortunately, it overshot the target by far. Now, as soon as I make two edits in close succession (which happens *often* – I’m sloppy), I am presented with a “human verification” and a **totally unreadable captcha.** It takes an average of five reloads to get a marginally readable one, and even then I’m guessing (and sometimes guessing wrong).
Please tune down the filter, or at least switch to a readable captcha.
In fact, wasn’t there previously a rule that once contributors had enough reputation, they’d be trusted not to be bots? Did that get switched off or am I remembering this wrong? | 2012/08/14 | [
"https://meta.stackexchange.com/questions/143455",
"https://meta.stackexchange.com",
"https://meta.stackexchange.com/users/1968/"
] | Google announced today that they've made reCAPTCHAs considerably easier to read. [But *only* if you're not a robot](http://googleonlinesecurity.blogspot.com/2013/10/recaptcha-just-got-easier-but-only-if.html):
>
> As part of this, we’ve recently released an update that creates different classes of CAPTCHAs for different kinds of users. This multi-faceted approach allows us to determine whether a potential user is actually a human or not, and serve our legitimate users CAPTCHAs that most of them will find easy to solve. Bots, on the other hand, will see CAPTCHAs that are considerably more difficult and designed to stop them from getting through.
>
>
>
You can [test this out](https://stackoverflow.com/captcha) of you want. Here's the CAPTCHA I got:
That was so easy, I even bothered to fill in the alt text on that image! And if you happen to be using a keyboard with a separate pad for numbers, you should find this even easier (I'm typing this on my laptop while standing up).
Given how well the new human-biased system works, I'm marking this status-completed.
Of course, if you were lying and *are* indeed a robot, you should probably not be happy about this. | I honestly think that the only problem the editing system *might* be bringing to Stackoverflow is large-scale vandalism. When it comes to that, I believe there are three attack sources
1. Anonymous users
2. 2k- rep users
3. 2k+ rep users
The review system already tackles the first two. I personally think that it's highly unlikely that a spammer would train robot accounts until they have 2k rep so they can bypass the review system (think how hard it was to get your first 2k rep)
That's why I think that **5 seconds** is a very decent waiting time between edits and when you're gonna show some CAPTCHAs, why not a user-friendly one like [SolveMedia](http://www.solvemedia.com)
**Edit:** Don't get me wrong, I'm all for stopping spammers and whatnots. But do we (You, Stackoverflow) need to nuke the house just get rid of cockroaches?
**Edit 2:** @nhahtdh's scenario is a perfect example of when a CAPTCHA should be deployed, when there's a *suspicious* behavior.
The key here is gradually escalating the measurements:
* 10 edit in 1 minute on different posts => suspicious => introduce CAPTCHA
* Same user did it again? Introduce CAPTCHA & Inform a moderator.
* Same user did it AGAIN? Suspend editing privileges.
In this case, you didn't annoy legit users AND minimized the damage of the **2k rep user** (and I don't think this will happen a lot).
Note: It took me 6 CAPTCHA retries to make this edit. |
143,455 | Some days ago, the spam protection was turned up a notch.
Unfortunately, it overshot the target by far. Now, as soon as I make two edits in close succession (which happens *often* – I’m sloppy), I am presented with a “human verification” and a **totally unreadable captcha.** It takes an average of five reloads to get a marginally readable one, and even then I’m guessing (and sometimes guessing wrong).
Please tune down the filter, or at least switch to a readable captcha.
In fact, wasn’t there previously a rule that once contributors had enough reputation, they’d be trusted not to be bots? Did that get switched off or am I remembering this wrong? | 2012/08/14 | [
"https://meta.stackexchange.com/questions/143455",
"https://meta.stackexchange.com",
"https://meta.stackexchange.com/users/1968/"
] | Over almost ***four years*** on Stack Overflow, Konrad has earned almost ***150k rep***. A highly committed Stack Overflow citizen, with ***2.5k answers*** and a mere 60 questions, he's one of those users that made Stack Overflow famous. He has ***40(!) accounts*** across Stack Exchange, eight of which sport ***>1k rep***. He is ***a moderator*** on one site.
Is anybody *really and seriously* trying to tell me ***nagging such a user with CAPTCHAs*** is doing the Stack Exchange network a favor? | I honestly think that the only problem the editing system *might* be bringing to Stackoverflow is large-scale vandalism. When it comes to that, I believe there are three attack sources
1. Anonymous users
2. 2k- rep users
3. 2k+ rep users
The review system already tackles the first two. I personally think that it's highly unlikely that a spammer would train robot accounts until they have 2k rep so they can bypass the review system (think how hard it was to get your first 2k rep)
That's why I think that **5 seconds** is a very decent waiting time between edits and when you're gonna show some CAPTCHAs, why not a user-friendly one like [SolveMedia](http://www.solvemedia.com)
**Edit:** Don't get me wrong, I'm all for stopping spammers and whatnots. But do we (You, Stackoverflow) need to nuke the house just get rid of cockroaches?
**Edit 2:** @nhahtdh's scenario is a perfect example of when a CAPTCHA should be deployed, when there's a *suspicious* behavior.
The key here is gradually escalating the measurements:
* 10 edit in 1 minute on different posts => suspicious => introduce CAPTCHA
* Same user did it again? Introduce CAPTCHA & Inform a moderator.
* Same user did it AGAIN? Suspend editing privileges.
In this case, you didn't annoy legit users AND minimized the damage of the **2k rep user** (and I don't think this will happen a lot).
Note: It took me 6 CAPTCHA retries to make this edit. |
84,595 | Is there a way to install full coverage fenders without a chainstay bridge on this bike?
I'm looking at alloy fenders in the style of [velo-orange](https://velo-orange.com/collections/700c-fenders) & [planet bike](https://www.planetbike.com/cascadia-alx-bike-fenders-700c-x-43mm/)'s full coverage fenders as they seem to be able to prevent road spray from hitting the bottom bracket area.
There are fender eyelets near the dropouts and a mounting point on the underneath of the seatstay bridge.
[This idea](https://www.bikeforums.net/12506197-post5.html) using a light mount seems like a good starting place but I don't think the clamp is a good match for the flat shape of this bike's chainstays.
Any idea how I could get the front mounting point of the fenders attached to the bottom bracket area of this bike? Maybe stainless steel P-clamps and an angle bracket?
[](https://i.stack.imgur.com/45XAm.jpg)
[](https://i.stack.imgur.com/O2hAW.jpg)
[](https://i.stack.imgur.com/2gr8z.jpg)
[](https://i.stack.imgur.com/3KWwl.jpg)
[](https://i.stack.imgur.com/JXnVI.jpg) | 2022/06/28 | [
"https://bicycles.stackexchange.com/questions/84595",
"https://bicycles.stackexchange.com",
"https://bicycles.stackexchange.com/users/36447/"
] | Looks like tubular rims to me. Most of the discolouration will be glue and not rust.
You need
* Hot air gun - a hairdryer might work but they don't put out as much heat
* Wooden popsicle sticks, with a rounded end.
* Wheel truing fixture OR an old fork in a bench vise OR the bike's frame.
* Glove for heat protection, or rags to protect your hand
* More rags/paper towels to wipe up glue waste
Mount your wheel so it spins freely. Use the hot air gun to soften an area of glue between two spoke holes. Play the hot air around and don't focus in one area. Try and pre-warm the next sector upward too (heat rises)
The glue will soften and then you can scratch the bulk of it off using the wooden sticks. The last bits can be wiped up with the rag.
**Be careful**, the glue will be over 100 degrees C and **will** burn you.
The glue is somewhat wet too, so it may run, it will soak into cloth, and it will adhere to skin continuing to burn.
The rim will also be hot, and this heat could damage stickers/decals.
Work quickly, and be prepared to do multiple laps of the whole wheel. You don't have to get it perfect either - 95% clean is good enough.
---
When refitting the new tubular tyre, its personal preference if you want to use tubular glue or tape. Both are messy, tape somewhat less so.
Remember glue-up takes a while - do it properly and you'll have a well-bonded tyre. Expect to take a couple days for a complete cured tyre.
---
I really like riding on tubulars, but they're such a faff and a puncture en-route is often ride-ending. As such clinchers are more practical. So I save my tubular wheels for the annual Merckx time trial on my `80s road bike, along with the wool jersey and leather shoes. | Are those steel or aluminum? Are they worth much to you or on the market?
This probably isn't the most professional answer, but I recently got some old steel rims that were covered in surface rust. I used a steel brush attachment for a battery-powered drill, I doused the rims in rust remover (hydrochloric and phosphoric acid), and when the material was clean enough of rust to my liking, I sprayed on 2-3 layers of spray-paint clearcoat to prevent further major outbursts of rust.
Obviously this scratched the wheels, but they aren't worth much and I just needed a fix good enough to be able to ride the bike without worrying about rust eating through my tubes and tyres.
If your rims are aluminum then this advice does not apply (aluminum does not rust). Likewise you wouldn't want to scratch up a rare and expensive wheelset with an iron brush.
NB. If what we're looking at is just glue from old tubular tires, you might have luck with various solvents. WD-40, paint thinner, etc. have all done the trick for various glues in my experience, without damaging the underlying material. |
312,713 | I'd like to hide my other accounts on a single Stack Exchange site, but not all of them. I found the "hide communities" section, but when I go there on the site I'd like to be more private and remove communities, it appears to hide them on all my accounts.
Is it possible to hide communities on a single site, but leave them publicly visible everywhere else? | 2018/07/17 | [
"https://meta.stackexchange.com/questions/312713",
"https://meta.stackexchange.com",
"https://meta.stackexchange.com/users/145819/"
] | No, you cannot
Once you hide it from
**<https://askubuntu.com/users/hidecommunities/current>** say, it will be reflected directly in
**<https://meta.stackoverflow.com/users/hidecommunities/current>**
The websites are interlinked and changing in one instantly reflects in other ones. | Hiding community(es) on the single site is not possible and useless.
If the community is not hidden anybody can access you [network profile](https://stackexchange.com/users/295527/bijendra?tab=accounts) via corresponding link in the currect community profile section.
Network profile contains a link of all your publicly visible accounts. So if hiding a community on the single site was possible it's unclear what should be displayed in such list. Hence it's not allowed. |
603,658 | i created a web service, upload it to my site on a remote server.
i tried to browse it but i cant, i also tried to add web reference to his adress through vs08 but the same problem happened there. | 2009/03/02 | [
"https://Stackoverflow.com/questions/603658",
"https://Stackoverflow.com",
"https://Stackoverflow.com/users/67505/"
] | It is not possible to modify the default screen of a device with J2ME. You need a native application (Symbian, Windows Mobile) to do so. J2ME lays in a sandboxed environment and has many restrictions on what you can access. An application can only be started by the user and can't run as a service. It is also not possible to register an application to run at the start-up of the phone.
It has been discussed that MIDP 3.0 may address many of the above issues, but I don't think it will ever be available. | From an application lifecycle point of view, there are ways to approximate what you are trying to do but they almost unvariably require handset manufacturer support.
If you have a choice, the Sony Ericsson JP8 platform has non-standard extensions to JavaME that can help.
Accessing telephony information, however will be a major issue. Look for a handset that implements the cbs protocol of JSR-120, it could prove useful.
Accessing the phone idle/standby/main screen on Series60 (Symbian) phones will require nokia support too, BTW. |
6,539 | Does anyone know of interesting applications of [Gröbner bases](http://en.wikipedia.org/wiki/Gr%C3%B6bner_basis) to theoretical computer science?
Gröbner bases are used to solve multi-variate polynomial equations, an NP-hard problem in general. I was wondering whether some tractable special cases were used to provide efficient algorithms/constructions/proofs in TCS or TCS-related areas (combinatorics, coding theory). | 2011/05/12 | [
"https://cstheory.stackexchange.com/questions/6539",
"https://cstheory.stackexchange.com",
"https://cstheory.stackexchange.com/users/1621/"
] | In proof complexity the use of Gröbner bases has been proposed by [Clegg, Edmonds, Impagliazzo](http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.42.2402) to refute CNFs. There are cases in which this proof system outperforms Resolution exponentially but it does not seem to me that there is a real performance improvement for general instances.
It is also true that many of the lower bounds for Resolution hold for Polynomial Calculus (a proof system based on Gröbner bases). The exceptions usually are built for the characteristic of the underlying field. This means that working in $GF(2)$ can help you on some formulas but not on others.
Yet Polynomial Calculus has not been studied as much as Resolution, thus well tested heuristics are not available.
See also [this](http://martinralbrecht.files.wordpress.com/2010/10/phd.pdf) this for application in cryptanalysyis (I don't know very much about that). | Following <http://arxiv.org/pdf/1502.05912.pdf> sometimes grobner basis are used to decide isomorphism (when graphs are encoded by systems of equations). But this joins the use of grobner basis in refutating CNFS. |
6,539 | Does anyone know of interesting applications of [Gröbner bases](http://en.wikipedia.org/wiki/Gr%C3%B6bner_basis) to theoretical computer science?
Gröbner bases are used to solve multi-variate polynomial equations, an NP-hard problem in general. I was wondering whether some tractable special cases were used to provide efficient algorithms/constructions/proofs in TCS or TCS-related areas (combinatorics, coding theory). | 2011/05/12 | [
"https://cstheory.stackexchange.com/questions/6539",
"https://cstheory.stackexchange.com",
"https://cstheory.stackexchange.com/users/1621/"
] | Gröbner bases have been applied to constraint satisfaction problems (see this [grant](http://gow.epsrc.ac.uk/ViewGrant.ASPx?Grant=EP/D032636/1)). At this point Gröbner basis techniques do not appear to be useful for the applications of constraint satisfaction, since they are competing with mature search heuristics, consistency enforcement techniques, and efficient special purpose propagators -- not to mention good general-purpose SAT solvers. However, I think there are definitely theoretical uses waiting to be discovered, specifically when the Gröbner basis has reasonable size. See also the paper by [Jefferson, Jeavons, Green, and van Dongen](http://www-spiral.lip6.fr/MACIS2007/Papers/submission_7.pdf), presented at MACIS 2007 (journal version: AMAI **67** 359–382, 2013, doi:[10.1007/s10472-013-9365-7](http://dx.doi.org/10.1007/s10472-013-9365-7)), which discusses some of the issues. | The following paper can be seen as one application.
* Gunnar Carlsson, Gurjeet Singh, Afra Zomorodian: Computing Multidimensional Persistence. Journal of Computational Geometry, 1(1) 2010, pages 72-100. <https://doi.org/10.20382/jocg.v1i1a6>
I see the authors use Buchberger's algorithm as a subroutine, and exploit the structure of their problem to prove that the running time is polynomially bounded. |
6,539 | Does anyone know of interesting applications of [Gröbner bases](http://en.wikipedia.org/wiki/Gr%C3%B6bner_basis) to theoretical computer science?
Gröbner bases are used to solve multi-variate polynomial equations, an NP-hard problem in general. I was wondering whether some tractable special cases were used to provide efficient algorithms/constructions/proofs in TCS or TCS-related areas (combinatorics, coding theory). | 2011/05/12 | [
"https://cstheory.stackexchange.com/questions/6539",
"https://cstheory.stackexchange.com",
"https://cstheory.stackexchange.com/users/1621/"
] | Gröbner basis computation, while EXPSPACE-complete in general, are in PSPACE over Boolean rings. This has applications in model-checking to replace BDDs: Quoc-Nam Tran, "A PSPACE Algorithm for Groebner Bases Computation in Boolean Rings", Proc. WASET, Vol. 35, Nov. 2008, ISSN 2070-3740
**[NOTE]** The result stating that Groebner basis computation is in PSPACE over Boolean rings seems wrong, see Mark van Hoeij, **Gröbner basis in Boolean rings is not P-SPACE**, arXiv:[1502.07220](http://arxiv.org/abs/1502.07220), 2015.
**[NOTE]** The claim that the result stating that Groebner basis computation is in PSPACE over Boolean rings seems wrong, is wrong. The author confuses PSPACE-computability with having a polynomial size. A PSPACE function may well have exponentially long output. | Grobner bases are used for the fastest list decoding algorithms for Reed-Solomon codes:
<http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.320.1170&rep=rep1&type=pdf> |
6,539 | Does anyone know of interesting applications of [Gröbner bases](http://en.wikipedia.org/wiki/Gr%C3%B6bner_basis) to theoretical computer science?
Gröbner bases are used to solve multi-variate polynomial equations, an NP-hard problem in general. I was wondering whether some tractable special cases were used to provide efficient algorithms/constructions/proofs in TCS or TCS-related areas (combinatorics, coding theory). | 2011/05/12 | [
"https://cstheory.stackexchange.com/questions/6539",
"https://cstheory.stackexchange.com",
"https://cstheory.stackexchange.com/users/1621/"
] | Gröbner bases have been applied to constraint satisfaction problems (see this [grant](http://gow.epsrc.ac.uk/ViewGrant.ASPx?Grant=EP/D032636/1)). At this point Gröbner basis techniques do not appear to be useful for the applications of constraint satisfaction, since they are competing with mature search heuristics, consistency enforcement techniques, and efficient special purpose propagators -- not to mention good general-purpose SAT solvers. However, I think there are definitely theoretical uses waiting to be discovered, specifically when the Gröbner basis has reasonable size. See also the paper by [Jefferson, Jeavons, Green, and van Dongen](http://www-spiral.lip6.fr/MACIS2007/Papers/submission_7.pdf), presented at MACIS 2007 (journal version: AMAI **67** 359–382, 2013, doi:[10.1007/s10472-013-9365-7](http://dx.doi.org/10.1007/s10472-013-9365-7)), which discusses some of the issues. | Following <http://arxiv.org/pdf/1502.05912.pdf> sometimes grobner basis are used to decide isomorphism (when graphs are encoded by systems of equations). But this joins the use of grobner basis in refutating CNFS. |
6,539 | Does anyone know of interesting applications of [Gröbner bases](http://en.wikipedia.org/wiki/Gr%C3%B6bner_basis) to theoretical computer science?
Gröbner bases are used to solve multi-variate polynomial equations, an NP-hard problem in general. I was wondering whether some tractable special cases were used to provide efficient algorithms/constructions/proofs in TCS or TCS-related areas (combinatorics, coding theory). | 2011/05/12 | [
"https://cstheory.stackexchange.com/questions/6539",
"https://cstheory.stackexchange.com",
"https://cstheory.stackexchange.com/users/1621/"
] | Gröbner basis computation, while EXPSPACE-complete in general, are in PSPACE over Boolean rings. This has applications in model-checking to replace BDDs: Quoc-Nam Tran, "A PSPACE Algorithm for Groebner Bases Computation in Boolean Rings", Proc. WASET, Vol. 35, Nov. 2008, ISSN 2070-3740
**[NOTE]** The result stating that Groebner basis computation is in PSPACE over Boolean rings seems wrong, see Mark van Hoeij, **Gröbner basis in Boolean rings is not P-SPACE**, arXiv:[1502.07220](http://arxiv.org/abs/1502.07220), 2015.
**[NOTE]** The claim that the result stating that Groebner basis computation is in PSPACE over Boolean rings seems wrong, is wrong. The author confuses PSPACE-computability with having a polynomial size. A PSPACE function may well have exponentially long output. | Gröbner bases have been applied to constraint satisfaction problems (see this [grant](http://gow.epsrc.ac.uk/ViewGrant.ASPx?Grant=EP/D032636/1)). At this point Gröbner basis techniques do not appear to be useful for the applications of constraint satisfaction, since they are competing with mature search heuristics, consistency enforcement techniques, and efficient special purpose propagators -- not to mention good general-purpose SAT solvers. However, I think there are definitely theoretical uses waiting to be discovered, specifically when the Gröbner basis has reasonable size. See also the paper by [Jefferson, Jeavons, Green, and van Dongen](http://www-spiral.lip6.fr/MACIS2007/Papers/submission_7.pdf), presented at MACIS 2007 (journal version: AMAI **67** 359–382, 2013, doi:[10.1007/s10472-013-9365-7](http://dx.doi.org/10.1007/s10472-013-9365-7)), which discusses some of the issues. |
85,759 | We recently conducted an repeated measures experiment consisting of two conditions. Each condition consistent of three tasks. The tasks are seen as random factors because they are not comparable among themselves. We measured the task completion time.
I have seen something similar, that was evaluated using ANCOVA, but I don't understand why you would use ANCOVA and not a Repeated Measures ANOVA.
Is ANCOVA more suitable due to the fact, that each task is different?
I am really new to Statistics. Maybe somebody can shed some light on that topic for me? | 2014/02/07 | [
"https://stats.stackexchange.com/questions/85759",
"https://stats.stackexchange.com",
"https://stats.stackexchange.com/users/39691/"
] | When repeated measurements are taken on subject - either over time or with different conditions - then the within-subject correlation must be accounted for.
Repeated measures ANOVAs accomplish this by adjusting for the contributions of each individual as fixed effects in the model (a dummy variable for each individual). The ANCOVA approach deals with the inter-dependence by testing the effect of the treatment on the post-measure while adjusting for the initial measurement as a fixed effect.
However, ANCOVA would only be suitable for Pre vs. Post because the model readily describes the relevant question: "After controlling for initial levels, did the treatment(s) increase or decrease the dependent variable relative to the control group(s)?" The limitation, as discussed in the above threads, is that ANCOVA cannot determine if the dependent variable differed by treatment at baseline. This generalizes poorly to your experimental design.
You are interested in whether the condition affects the outcome across each task (main effect of condition) and, perhaps, whether the effect of the condition varies with the task (interaction). This would be similar to the Pre/Post case in needing to know whether the outcome varied by treatment at baseline and at the end, which ANCOVA cannot determine. Furthermore, it's unclear how the ANCOVA would be specified with more than two tasks. Is the effect of treatment on time in Task A adjusted for Task B and C, or is the outcome Task B and adjusted for A and C? Although I suppose this kind of comparison could arise in some circumstances.
Thus, ANCOVA is fine for Pre/Post comparison, but repeated measures ANOVA would be more suitable for your design. | I have often read and heard that a) repeated measure ANOVA and b) ANCOVA , the two analyses answer different research questions.
Sometimes, it's not rare seen Researcher disagreeing with the supervisor based on which Analysis would do the right justice to the research question.
I believe that when your research objective is about the mean gain, growth, or change comparing two groups in a pre-post test research (or two groups; of intervention and placebo) the repeated measure ANOVA (time\*subject interaction) really messure this changes. As @moose, it is safe to limit the use of ANCOVA to comparing means of two groups, where you have group(intervention) A, B, C, etc you really need the ANOVA. |
372 | If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, is my readback considered the report specified in the AIM, or do I have to inform them when I actually start down?
>
> **[AIM 5-3-3.](http://www.faa.gov/air_traffic/publications/ATpubs/AIM/aim0503.html) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
> ...
>
>
>
An Example - Say that a pilot is flying at flight level 340 100 NM from Wilmington VOR and gets the following clearance:
>
> ATC: N1234, cross Wilmington VOR at flight level 240
>
> Pilot: Cross Wilmington VOR at flight level 240, N1234
>
>
>
or
>
> ATC: N1234, descend at pilot's discretion to flight level 240
>
> Pilot: Descend at pilot's discretion to flight level 240
>
>
>
It's a little early to start down since we want to stay high for fuel efficiency, so the pilot decides to wait until 30 NM from the VOR to start down. When they reach that point, are they required to inform ATC before starting the descent or are they considered to have reported the descent earlier?
I hear pilots that do it both ways and each camp is pretty emphatic about it.... | 2013/12/25 | [
"https://aviation.stackexchange.com/questions/372",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/69/"
] | >
> **[AIM 5-3-3.](http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/0/2a2b29ae7f0732e886257384006cb117!OpenDocument) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) **When vacating** any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
>
Emphasis mine. The phrase 'when vacating' is pretty unambiguous.
Edited answer to better respond to your comment. Previous answer below.
---
The AIM explains the purpose of readbacks in [4-4-7b](http://www.faa.gov/air_traffic/publications/atpubs/aim/aim0404.html):
>
> ATC Clearance/Instruction Readback.
> Pilots of airborne aircraft should read back those parts of ATC clearances and instructions containing altitude assignments, vectors, or runway assignments as a means of **mutual verification**. The read back of the “numbers" **serves as a double check** between pilots and controllers and reduces the kinds of communications errors that occur when a number is either “misheard" or is incorrect.
>
>
>
Although this is stretching, I find it easier to believe that a readback does not qualify and you should call again when you actually start down.
Furthermore, the AIM references [FAR 91.183](http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/0/2a2b29ae7f0732e886257384006cb117!OpenDocument), which says that the pilot of an aircraft operating under IFR must report as soon as possible
>
> (c) Any other information relating to the safety of flight.
>
>
>
If you figure altitude changes qualify as safety of flight information, it's probably not a bad idea to make a second radio call. | Absolutely report leaving the previously assigned altitude. And this applies equally when receiving a clearance "cleared for the approach." I recall once being cleared for an approach from a holding pattern. Planes were stacked above me. I wanted to maintain my holding altitude until over the holding fix. Thus I did not say, "Leaving 2000 feet." I left that altitude quickly when approach control told the plane above me to descend to 2,000 feet. |
372 | If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, is my readback considered the report specified in the AIM, or do I have to inform them when I actually start down?
>
> **[AIM 5-3-3.](http://www.faa.gov/air_traffic/publications/ATpubs/AIM/aim0503.html) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
> ...
>
>
>
An Example - Say that a pilot is flying at flight level 340 100 NM from Wilmington VOR and gets the following clearance:
>
> ATC: N1234, cross Wilmington VOR at flight level 240
>
> Pilot: Cross Wilmington VOR at flight level 240, N1234
>
>
>
or
>
> ATC: N1234, descend at pilot's discretion to flight level 240
>
> Pilot: Descend at pilot's discretion to flight level 240
>
>
>
It's a little early to start down since we want to stay high for fuel efficiency, so the pilot decides to wait until 30 NM from the VOR to start down. When they reach that point, are they required to inform ATC before starting the descent or are they considered to have reported the descent earlier?
I hear pilots that do it both ways and each camp is pretty emphatic about it.... | 2013/12/25 | [
"https://aviation.stackexchange.com/questions/372",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/69/"
] | Short Answer
------------
No, but you should.
---
Long Answer
-----------
I see two questions which I will answer—or attempt to answer—each in turn. Firstly, from the title:
>
> **Are you required to report leaving an altitude if you have been given a crossing restriction?**
>
>
>
And secondly:
>
> If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, **is my readback considered the report specified in the AIM**, or do I have to inform them when I actually start down?
>
>
>
---
To the first question: no, you are not *required* to report leaving any altitude. Those items that *must* be reported are listed in [14 CFR 91.183](http://www.ecfr.gov/cgi-bin/text-idx?SID=35798ade8bbc9ad25108255889cd363b&mc=true&node=se14.2.91_1183&rgn=div8), including:
>
> (a) The time and altitude of passing each designated reporting point,
> or the reporting points specified by ATC, except that while the
> aircraft is under radar control, only the passing of those reporting
> points specifically requested by ATC need be reported;
>
>
> (b) Any unforecast weather conditions encountered; and
>
>
> (c) Any other information relating to the safety of flight.
>
>
>
Leaving an altitude is clearly not listed here. However, as you note, the "leaving an altitude report" is found in the the [Aeronautical Information Manual (AIM)](https://www.faa.gov/air_traffic/publications/media/aim.pdf):
>
> **[5-3-3](http://www.pilotfriend.com/aero%20information/ATP3.htm#5-3-3). Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
>
When the FAA means for something to be mandatory, the word "[must](https://www.faa.gov/about/initiatives/plain_language/articles/mandatory/)" is used in regulation. However, the FAA's Plain Language Program Manager helps us understand the use of "[should](https://www.faa.gov/about/initiatives/plain_language/articles/authority/)" as "meaning optional but implies that the writer recommends and advises the reader to use that option." Moreover, given that the AIM is itself [not regulatory](https://aviation.stackexchange.com/a/32942/12720), we can interpret the plain language of the above excerpt at face value: the report *should* be made, but is not *[mandatory](http://www.thefreedictionary.com/mandatory)* or *[required](http://legal-dictionary.thefreedictionary.com/required)*.
Though optional, the report is generally a good idea, recommended, advisable, and in keeping with best practice. You *should* give that report, even if the pilot flying gives you a funny look. I too hear some pilots give the report, and I find there are perhaps more that omit it. I have come to consider the making of that report to be one of many marks that indicate disciplined airmanship.
From a more subjective standpoint, I acknowledge that there may be valid reasons to omit the report. Indeed some jurisdictions explicitly *do not* require the report in radar environments unless requested by ATC. From personal experience, controllers generally seem uninterested in a vacating altitude report.
But, the FAA says you *should* make the report.
---
To the second question: no, probably not. If you readback a clearance for descent at pilot's discretion, that is a clearance readback, not a vacating altitude report. Moreover, if you receive that clearance and then commence the descent at some other time, the readback is not satisfying the "when" part of "when vacating any previously assigned altitude".
In your specific example of a descent clearance received and readback 70 NM prior to commencing descent, that readback would not comprise a report made *when* vacating FL340. | >
> **[AIM 5-3-3.](http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/0/2a2b29ae7f0732e886257384006cb117!OpenDocument) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) **When vacating** any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
>
Emphasis mine. The phrase 'when vacating' is pretty unambiguous.
Edited answer to better respond to your comment. Previous answer below.
---
The AIM explains the purpose of readbacks in [4-4-7b](http://www.faa.gov/air_traffic/publications/atpubs/aim/aim0404.html):
>
> ATC Clearance/Instruction Readback.
> Pilots of airborne aircraft should read back those parts of ATC clearances and instructions containing altitude assignments, vectors, or runway assignments as a means of **mutual verification**. The read back of the “numbers" **serves as a double check** between pilots and controllers and reduces the kinds of communications errors that occur when a number is either “misheard" or is incorrect.
>
>
>
Although this is stretching, I find it easier to believe that a readback does not qualify and you should call again when you actually start down.
Furthermore, the AIM references [FAR 91.183](http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/0/2a2b29ae7f0732e886257384006cb117!OpenDocument), which says that the pilot of an aircraft operating under IFR must report as soon as possible
>
> (c) Any other information relating to the safety of flight.
>
>
>
If you figure altitude changes qualify as safety of flight information, it's probably not a bad idea to make a second radio call. |
372 | If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, is my readback considered the report specified in the AIM, or do I have to inform them when I actually start down?
>
> **[AIM 5-3-3.](http://www.faa.gov/air_traffic/publications/ATpubs/AIM/aim0503.html) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
> ...
>
>
>
An Example - Say that a pilot is flying at flight level 340 100 NM from Wilmington VOR and gets the following clearance:
>
> ATC: N1234, cross Wilmington VOR at flight level 240
>
> Pilot: Cross Wilmington VOR at flight level 240, N1234
>
>
>
or
>
> ATC: N1234, descend at pilot's discretion to flight level 240
>
> Pilot: Descend at pilot's discretion to flight level 240
>
>
>
It's a little early to start down since we want to stay high for fuel efficiency, so the pilot decides to wait until 30 NM from the VOR to start down. When they reach that point, are they required to inform ATC before starting the descent or are they considered to have reported the descent earlier?
I hear pilots that do it both ways and each camp is pretty emphatic about it.... | 2013/12/25 | [
"https://aviation.stackexchange.com/questions/372",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/69/"
] | >
> **[AIM 5-3-3.](http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/0/2a2b29ae7f0732e886257384006cb117!OpenDocument) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) **When vacating** any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
>
Emphasis mine. The phrase 'when vacating' is pretty unambiguous.
Edited answer to better respond to your comment. Previous answer below.
---
The AIM explains the purpose of readbacks in [4-4-7b](http://www.faa.gov/air_traffic/publications/atpubs/aim/aim0404.html):
>
> ATC Clearance/Instruction Readback.
> Pilots of airborne aircraft should read back those parts of ATC clearances and instructions containing altitude assignments, vectors, or runway assignments as a means of **mutual verification**. The read back of the “numbers" **serves as a double check** between pilots and controllers and reduces the kinds of communications errors that occur when a number is either “misheard" or is incorrect.
>
>
>
Although this is stretching, I find it easier to believe that a readback does not qualify and you should call again when you actually start down.
Furthermore, the AIM references [FAR 91.183](http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/0/2a2b29ae7f0732e886257384006cb117!OpenDocument), which says that the pilot of an aircraft operating under IFR must report as soon as possible
>
> (c) Any other information relating to the safety of flight.
>
>
>
If you figure altitude changes qualify as safety of flight information, it's probably not a bad idea to make a second radio call. | In the US...
Under radar contact the leaving level phraseology is not expected nor needed by ATC. What they do need is you tell them what altitude you are at (plus climbing/descend to) when you check in.
The leaving level is mandatory when flying without radar contact.
But AIM tells us to do it anyways.
I listened in nearly 100 hours of recent flying (Premier 1 Driver on youtube), and he never uses leaving level, ATC never asks him to. Other pilots don't use it either.
It is confusing because the AIM teaches us to do it, as well as my instructor did when I got my IFR rating. And it used to be SOP even in radar contact a long time ago.
I'm PPSEL IFR USA. But I haven't flown in 15 years.
Ok, I can't add a comment to user331's answer which conflicts with mine, so let me ask here.
Go out and listen to tens and tens of hours of ATC comms.
You will find out that what's being done is reading back the descent clearance.
When the descent is immediate that creates the impression that the purpose of the readback is to confirm leaving that level, but when its a PD or a descent with a constraint that can be delayed, you will find the pilot doesn't come back and informs leaving later.
So what I said matches real world actions.
If ATC wanted us to report actually leaving the altitude, they would be chastizing every body for not reporting when the altitude change is delayed. The practical reason is simple, under radar contact ATC can see your descent on radar. Without radar contact its a very different deal, ATC cannot see your transponder altitude so they cannot confirm you are descending, vacating your original altitude so actual confirmation is required. |
372 | If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, is my readback considered the report specified in the AIM, or do I have to inform them when I actually start down?
>
> **[AIM 5-3-3.](http://www.faa.gov/air_traffic/publications/ATpubs/AIM/aim0503.html) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
> ...
>
>
>
An Example - Say that a pilot is flying at flight level 340 100 NM from Wilmington VOR and gets the following clearance:
>
> ATC: N1234, cross Wilmington VOR at flight level 240
>
> Pilot: Cross Wilmington VOR at flight level 240, N1234
>
>
>
or
>
> ATC: N1234, descend at pilot's discretion to flight level 240
>
> Pilot: Descend at pilot's discretion to flight level 240
>
>
>
It's a little early to start down since we want to stay high for fuel efficiency, so the pilot decides to wait until 30 NM from the VOR to start down. When they reach that point, are they required to inform ATC before starting the descent or are they considered to have reported the descent earlier?
I hear pilots that do it both ways and each camp is pretty emphatic about it.... | 2013/12/25 | [
"https://aviation.stackexchange.com/questions/372",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/69/"
] | I’ve been a controller in both the en route and terminal environments. While I agree with your interpretation of the AIM that it appears to be required, reorting leaving your altitude is not expected and I did not usually hear it done.
To give the perspective from the other side of the mic, an altitude crossing restriction is functionally equivalent to a pilot’s discretion climb/descent to that point. ATC will protect all altitudes between your current one and the restriction, and you are free to hit that restriction as you see fit (barring the violation of other regulations, of course). You may not return to a previously vacated altitude as part of your climb/descent, but you may level.
You are also correct in that it can tie up the freq as an “unnecessary” call, but if you are unsure, better to over inform rather than under inform.
Incidentally, very few controllers read the AIM. The 7110.65 takes precedence, and I’ve actually had a supervisor yell at me for referring to the AIM once. I know, I know.
So, legally, it *should* be done. In practice? Unnecessary and I preferred that it not be done when I was working. | >
> **[AIM 5-3-3.](http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/0/2a2b29ae7f0732e886257384006cb117!OpenDocument) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) **When vacating** any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
>
Emphasis mine. The phrase 'when vacating' is pretty unambiguous.
Edited answer to better respond to your comment. Previous answer below.
---
The AIM explains the purpose of readbacks in [4-4-7b](http://www.faa.gov/air_traffic/publications/atpubs/aim/aim0404.html):
>
> ATC Clearance/Instruction Readback.
> Pilots of airborne aircraft should read back those parts of ATC clearances and instructions containing altitude assignments, vectors, or runway assignments as a means of **mutual verification**. The read back of the “numbers" **serves as a double check** between pilots and controllers and reduces the kinds of communications errors that occur when a number is either “misheard" or is incorrect.
>
>
>
Although this is stretching, I find it easier to believe that a readback does not qualify and you should call again when you actually start down.
Furthermore, the AIM references [FAR 91.183](http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/0/2a2b29ae7f0732e886257384006cb117!OpenDocument), which says that the pilot of an aircraft operating under IFR must report as soon as possible
>
> (c) Any other information relating to the safety of flight.
>
>
>
If you figure altitude changes qualify as safety of flight information, it's probably not a bad idea to make a second radio call. |
372 | If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, is my readback considered the report specified in the AIM, or do I have to inform them when I actually start down?
>
> **[AIM 5-3-3.](http://www.faa.gov/air_traffic/publications/ATpubs/AIM/aim0503.html) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
> ...
>
>
>
An Example - Say that a pilot is flying at flight level 340 100 NM from Wilmington VOR and gets the following clearance:
>
> ATC: N1234, cross Wilmington VOR at flight level 240
>
> Pilot: Cross Wilmington VOR at flight level 240, N1234
>
>
>
or
>
> ATC: N1234, descend at pilot's discretion to flight level 240
>
> Pilot: Descend at pilot's discretion to flight level 240
>
>
>
It's a little early to start down since we want to stay high for fuel efficiency, so the pilot decides to wait until 30 NM from the VOR to start down. When they reach that point, are they required to inform ATC before starting the descent or are they considered to have reported the descent earlier?
I hear pilots that do it both ways and each camp is pretty emphatic about it.... | 2013/12/25 | [
"https://aviation.stackexchange.com/questions/372",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/69/"
] | Short Answer
------------
No, but you should.
---
Long Answer
-----------
I see two questions which I will answer—or attempt to answer—each in turn. Firstly, from the title:
>
> **Are you required to report leaving an altitude if you have been given a crossing restriction?**
>
>
>
And secondly:
>
> If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, **is my readback considered the report specified in the AIM**, or do I have to inform them when I actually start down?
>
>
>
---
To the first question: no, you are not *required* to report leaving any altitude. Those items that *must* be reported are listed in [14 CFR 91.183](http://www.ecfr.gov/cgi-bin/text-idx?SID=35798ade8bbc9ad25108255889cd363b&mc=true&node=se14.2.91_1183&rgn=div8), including:
>
> (a) The time and altitude of passing each designated reporting point,
> or the reporting points specified by ATC, except that while the
> aircraft is under radar control, only the passing of those reporting
> points specifically requested by ATC need be reported;
>
>
> (b) Any unforecast weather conditions encountered; and
>
>
> (c) Any other information relating to the safety of flight.
>
>
>
Leaving an altitude is clearly not listed here. However, as you note, the "leaving an altitude report" is found in the the [Aeronautical Information Manual (AIM)](https://www.faa.gov/air_traffic/publications/media/aim.pdf):
>
> **[5-3-3](http://www.pilotfriend.com/aero%20information/ATP3.htm#5-3-3). Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
>
When the FAA means for something to be mandatory, the word "[must](https://www.faa.gov/about/initiatives/plain_language/articles/mandatory/)" is used in regulation. However, the FAA's Plain Language Program Manager helps us understand the use of "[should](https://www.faa.gov/about/initiatives/plain_language/articles/authority/)" as "meaning optional but implies that the writer recommends and advises the reader to use that option." Moreover, given that the AIM is itself [not regulatory](https://aviation.stackexchange.com/a/32942/12720), we can interpret the plain language of the above excerpt at face value: the report *should* be made, but is not *[mandatory](http://www.thefreedictionary.com/mandatory)* or *[required](http://legal-dictionary.thefreedictionary.com/required)*.
Though optional, the report is generally a good idea, recommended, advisable, and in keeping with best practice. You *should* give that report, even if the pilot flying gives you a funny look. I too hear some pilots give the report, and I find there are perhaps more that omit it. I have come to consider the making of that report to be one of many marks that indicate disciplined airmanship.
From a more subjective standpoint, I acknowledge that there may be valid reasons to omit the report. Indeed some jurisdictions explicitly *do not* require the report in radar environments unless requested by ATC. From personal experience, controllers generally seem uninterested in a vacating altitude report.
But, the FAA says you *should* make the report.
---
To the second question: no, probably not. If you readback a clearance for descent at pilot's discretion, that is a clearance readback, not a vacating altitude report. Moreover, if you receive that clearance and then commence the descent at some other time, the readback is not satisfying the "when" part of "when vacating any previously assigned altitude".
In your specific example of a descent clearance received and readback 70 NM prior to commencing descent, that readback would not comprise a report made *when* vacating FL340. | Absolutely report leaving the previously assigned altitude. And this applies equally when receiving a clearance "cleared for the approach." I recall once being cleared for an approach from a holding pattern. Planes were stacked above me. I wanted to maintain my holding altitude until over the holding fix. Thus I did not say, "Leaving 2000 feet." I left that altitude quickly when approach control told the plane above me to descend to 2,000 feet. |
372 | If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, is my readback considered the report specified in the AIM, or do I have to inform them when I actually start down?
>
> **[AIM 5-3-3.](http://www.faa.gov/air_traffic/publications/ATpubs/AIM/aim0503.html) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
> ...
>
>
>
An Example - Say that a pilot is flying at flight level 340 100 NM from Wilmington VOR and gets the following clearance:
>
> ATC: N1234, cross Wilmington VOR at flight level 240
>
> Pilot: Cross Wilmington VOR at flight level 240, N1234
>
>
>
or
>
> ATC: N1234, descend at pilot's discretion to flight level 240
>
> Pilot: Descend at pilot's discretion to flight level 240
>
>
>
It's a little early to start down since we want to stay high for fuel efficiency, so the pilot decides to wait until 30 NM from the VOR to start down. When they reach that point, are they required to inform ATC before starting the descent or are they considered to have reported the descent earlier?
I hear pilots that do it both ways and each camp is pretty emphatic about it.... | 2013/12/25 | [
"https://aviation.stackexchange.com/questions/372",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/69/"
] | I’ve been a controller in both the en route and terminal environments. While I agree with your interpretation of the AIM that it appears to be required, reorting leaving your altitude is not expected and I did not usually hear it done.
To give the perspective from the other side of the mic, an altitude crossing restriction is functionally equivalent to a pilot’s discretion climb/descent to that point. ATC will protect all altitudes between your current one and the restriction, and you are free to hit that restriction as you see fit (barring the violation of other regulations, of course). You may not return to a previously vacated altitude as part of your climb/descent, but you may level.
You are also correct in that it can tie up the freq as an “unnecessary” call, but if you are unsure, better to over inform rather than under inform.
Incidentally, very few controllers read the AIM. The 7110.65 takes precedence, and I’ve actually had a supervisor yell at me for referring to the AIM once. I know, I know.
So, legally, it *should* be done. In practice? Unnecessary and I preferred that it not be done when I was working. | Absolutely report leaving the previously assigned altitude. And this applies equally when receiving a clearance "cleared for the approach." I recall once being cleared for an approach from a holding pattern. Planes were stacked above me. I wanted to maintain my holding altitude until over the holding fix. Thus I did not say, "Leaving 2000 feet." I left that altitude quickly when approach control told the plane above me to descend to 2,000 feet. |
372 | If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, is my readback considered the report specified in the AIM, or do I have to inform them when I actually start down?
>
> **[AIM 5-3-3.](http://www.faa.gov/air_traffic/publications/ATpubs/AIM/aim0503.html) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
> ...
>
>
>
An Example - Say that a pilot is flying at flight level 340 100 NM from Wilmington VOR and gets the following clearance:
>
> ATC: N1234, cross Wilmington VOR at flight level 240
>
> Pilot: Cross Wilmington VOR at flight level 240, N1234
>
>
>
or
>
> ATC: N1234, descend at pilot's discretion to flight level 240
>
> Pilot: Descend at pilot's discretion to flight level 240
>
>
>
It's a little early to start down since we want to stay high for fuel efficiency, so the pilot decides to wait until 30 NM from the VOR to start down. When they reach that point, are they required to inform ATC before starting the descent or are they considered to have reported the descent earlier?
I hear pilots that do it both ways and each camp is pretty emphatic about it.... | 2013/12/25 | [
"https://aviation.stackexchange.com/questions/372",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/69/"
] | Short Answer
------------
No, but you should.
---
Long Answer
-----------
I see two questions which I will answer—or attempt to answer—each in turn. Firstly, from the title:
>
> **Are you required to report leaving an altitude if you have been given a crossing restriction?**
>
>
>
And secondly:
>
> If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, **is my readback considered the report specified in the AIM**, or do I have to inform them when I actually start down?
>
>
>
---
To the first question: no, you are not *required* to report leaving any altitude. Those items that *must* be reported are listed in [14 CFR 91.183](http://www.ecfr.gov/cgi-bin/text-idx?SID=35798ade8bbc9ad25108255889cd363b&mc=true&node=se14.2.91_1183&rgn=div8), including:
>
> (a) The time and altitude of passing each designated reporting point,
> or the reporting points specified by ATC, except that while the
> aircraft is under radar control, only the passing of those reporting
> points specifically requested by ATC need be reported;
>
>
> (b) Any unforecast weather conditions encountered; and
>
>
> (c) Any other information relating to the safety of flight.
>
>
>
Leaving an altitude is clearly not listed here. However, as you note, the "leaving an altitude report" is found in the the [Aeronautical Information Manual (AIM)](https://www.faa.gov/air_traffic/publications/media/aim.pdf):
>
> **[5-3-3](http://www.pilotfriend.com/aero%20information/ATP3.htm#5-3-3). Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
>
When the FAA means for something to be mandatory, the word "[must](https://www.faa.gov/about/initiatives/plain_language/articles/mandatory/)" is used in regulation. However, the FAA's Plain Language Program Manager helps us understand the use of "[should](https://www.faa.gov/about/initiatives/plain_language/articles/authority/)" as "meaning optional but implies that the writer recommends and advises the reader to use that option." Moreover, given that the AIM is itself [not regulatory](https://aviation.stackexchange.com/a/32942/12720), we can interpret the plain language of the above excerpt at face value: the report *should* be made, but is not *[mandatory](http://www.thefreedictionary.com/mandatory)* or *[required](http://legal-dictionary.thefreedictionary.com/required)*.
Though optional, the report is generally a good idea, recommended, advisable, and in keeping with best practice. You *should* give that report, even if the pilot flying gives you a funny look. I too hear some pilots give the report, and I find there are perhaps more that omit it. I have come to consider the making of that report to be one of many marks that indicate disciplined airmanship.
From a more subjective standpoint, I acknowledge that there may be valid reasons to omit the report. Indeed some jurisdictions explicitly *do not* require the report in radar environments unless requested by ATC. From personal experience, controllers generally seem uninterested in a vacating altitude report.
But, the FAA says you *should* make the report.
---
To the second question: no, probably not. If you readback a clearance for descent at pilot's discretion, that is a clearance readback, not a vacating altitude report. Moreover, if you receive that clearance and then commence the descent at some other time, the readback is not satisfying the "when" part of "when vacating any previously assigned altitude".
In your specific example of a descent clearance received and readback 70 NM prior to commencing descent, that readback would not comprise a report made *when* vacating FL340. | In the US...
Under radar contact the leaving level phraseology is not expected nor needed by ATC. What they do need is you tell them what altitude you are at (plus climbing/descend to) when you check in.
The leaving level is mandatory when flying without radar contact.
But AIM tells us to do it anyways.
I listened in nearly 100 hours of recent flying (Premier 1 Driver on youtube), and he never uses leaving level, ATC never asks him to. Other pilots don't use it either.
It is confusing because the AIM teaches us to do it, as well as my instructor did when I got my IFR rating. And it used to be SOP even in radar contact a long time ago.
I'm PPSEL IFR USA. But I haven't flown in 15 years.
Ok, I can't add a comment to user331's answer which conflicts with mine, so let me ask here.
Go out and listen to tens and tens of hours of ATC comms.
You will find out that what's being done is reading back the descent clearance.
When the descent is immediate that creates the impression that the purpose of the readback is to confirm leaving that level, but when its a PD or a descent with a constraint that can be delayed, you will find the pilot doesn't come back and informs leaving later.
So what I said matches real world actions.
If ATC wanted us to report actually leaving the altitude, they would be chastizing every body for not reporting when the altitude change is delayed. The practical reason is simple, under radar contact ATC can see your descent on radar. Without radar contact its a very different deal, ATC cannot see your transponder altitude so they cannot confirm you are descending, vacating your original altitude so actual confirmation is required. |
372 | If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, is my readback considered the report specified in the AIM, or do I have to inform them when I actually start down?
>
> **[AIM 5-3-3.](http://www.faa.gov/air_traffic/publications/ATpubs/AIM/aim0503.html) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
> ...
>
>
>
An Example - Say that a pilot is flying at flight level 340 100 NM from Wilmington VOR and gets the following clearance:
>
> ATC: N1234, cross Wilmington VOR at flight level 240
>
> Pilot: Cross Wilmington VOR at flight level 240, N1234
>
>
>
or
>
> ATC: N1234, descend at pilot's discretion to flight level 240
>
> Pilot: Descend at pilot's discretion to flight level 240
>
>
>
It's a little early to start down since we want to stay high for fuel efficiency, so the pilot decides to wait until 30 NM from the VOR to start down. When they reach that point, are they required to inform ATC before starting the descent or are they considered to have reported the descent earlier?
I hear pilots that do it both ways and each camp is pretty emphatic about it.... | 2013/12/25 | [
"https://aviation.stackexchange.com/questions/372",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/69/"
] | I’ve been a controller in both the en route and terminal environments. While I agree with your interpretation of the AIM that it appears to be required, reorting leaving your altitude is not expected and I did not usually hear it done.
To give the perspective from the other side of the mic, an altitude crossing restriction is functionally equivalent to a pilot’s discretion climb/descent to that point. ATC will protect all altitudes between your current one and the restriction, and you are free to hit that restriction as you see fit (barring the violation of other regulations, of course). You may not return to a previously vacated altitude as part of your climb/descent, but you may level.
You are also correct in that it can tie up the freq as an “unnecessary” call, but if you are unsure, better to over inform rather than under inform.
Incidentally, very few controllers read the AIM. The 7110.65 takes precedence, and I’ve actually had a supervisor yell at me for referring to the AIM once. I know, I know.
So, legally, it *should* be done. In practice? Unnecessary and I preferred that it not be done when I was working. | Short Answer
------------
No, but you should.
---
Long Answer
-----------
I see two questions which I will answer—or attempt to answer—each in turn. Firstly, from the title:
>
> **Are you required to report leaving an altitude if you have been given a crossing restriction?**
>
>
>
And secondly:
>
> If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, **is my readback considered the report specified in the AIM**, or do I have to inform them when I actually start down?
>
>
>
---
To the first question: no, you are not *required* to report leaving any altitude. Those items that *must* be reported are listed in [14 CFR 91.183](http://www.ecfr.gov/cgi-bin/text-idx?SID=35798ade8bbc9ad25108255889cd363b&mc=true&node=se14.2.91_1183&rgn=div8), including:
>
> (a) The time and altitude of passing each designated reporting point,
> or the reporting points specified by ATC, except that while the
> aircraft is under radar control, only the passing of those reporting
> points specifically requested by ATC need be reported;
>
>
> (b) Any unforecast weather conditions encountered; and
>
>
> (c) Any other information relating to the safety of flight.
>
>
>
Leaving an altitude is clearly not listed here. However, as you note, the "leaving an altitude report" is found in the the [Aeronautical Information Manual (AIM)](https://www.faa.gov/air_traffic/publications/media/aim.pdf):
>
> **[5-3-3](http://www.pilotfriend.com/aero%20information/ATP3.htm#5-3-3). Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
>
When the FAA means for something to be mandatory, the word "[must](https://www.faa.gov/about/initiatives/plain_language/articles/mandatory/)" is used in regulation. However, the FAA's Plain Language Program Manager helps us understand the use of "[should](https://www.faa.gov/about/initiatives/plain_language/articles/authority/)" as "meaning optional but implies that the writer recommends and advises the reader to use that option." Moreover, given that the AIM is itself [not regulatory](https://aviation.stackexchange.com/a/32942/12720), we can interpret the plain language of the above excerpt at face value: the report *should* be made, but is not *[mandatory](http://www.thefreedictionary.com/mandatory)* or *[required](http://legal-dictionary.thefreedictionary.com/required)*.
Though optional, the report is generally a good idea, recommended, advisable, and in keeping with best practice. You *should* give that report, even if the pilot flying gives you a funny look. I too hear some pilots give the report, and I find there are perhaps more that omit it. I have come to consider the making of that report to be one of many marks that indicate disciplined airmanship.
From a more subjective standpoint, I acknowledge that there may be valid reasons to omit the report. Indeed some jurisdictions explicitly *do not* require the report in radar environments unless requested by ATC. From personal experience, controllers generally seem uninterested in a vacating altitude report.
But, the FAA says you *should* make the report.
---
To the second question: no, probably not. If you readback a clearance for descent at pilot's discretion, that is a clearance readback, not a vacating altitude report. Moreover, if you receive that clearance and then commence the descent at some other time, the readback is not satisfying the "when" part of "when vacating any previously assigned altitude".
In your specific example of a descent clearance received and readback 70 NM prior to commencing descent, that readback would not comprise a report made *when* vacating FL340. |
372 | If ATC gives me a clearance to cross a fix at a specific altitude or a descent at pilot's discretion and I read back the clearance, is my readback considered the report specified in the AIM, or do I have to inform them when I actually start down?
>
> **[AIM 5-3-3.](http://www.faa.gov/air_traffic/publications/ATpubs/AIM/aim0503.html) Additional Reports**
>
>
> a. The following reports should be made to ATC or FSS facilities
> without a specific ATC request:
>
>
> 1. At all times.
>
>
> (a) When vacating any previously assigned altitude or flight level for
> a newly assigned altitude or flight level.
>
>
> ...
>
>
>
An Example - Say that a pilot is flying at flight level 340 100 NM from Wilmington VOR and gets the following clearance:
>
> ATC: N1234, cross Wilmington VOR at flight level 240
>
> Pilot: Cross Wilmington VOR at flight level 240, N1234
>
>
>
or
>
> ATC: N1234, descend at pilot's discretion to flight level 240
>
> Pilot: Descend at pilot's discretion to flight level 240
>
>
>
It's a little early to start down since we want to stay high for fuel efficiency, so the pilot decides to wait until 30 NM from the VOR to start down. When they reach that point, are they required to inform ATC before starting the descent or are they considered to have reported the descent earlier?
I hear pilots that do it both ways and each camp is pretty emphatic about it.... | 2013/12/25 | [
"https://aviation.stackexchange.com/questions/372",
"https://aviation.stackexchange.com",
"https://aviation.stackexchange.com/users/69/"
] | I’ve been a controller in both the en route and terminal environments. While I agree with your interpretation of the AIM that it appears to be required, reorting leaving your altitude is not expected and I did not usually hear it done.
To give the perspective from the other side of the mic, an altitude crossing restriction is functionally equivalent to a pilot’s discretion climb/descent to that point. ATC will protect all altitudes between your current one and the restriction, and you are free to hit that restriction as you see fit (barring the violation of other regulations, of course). You may not return to a previously vacated altitude as part of your climb/descent, but you may level.
You are also correct in that it can tie up the freq as an “unnecessary” call, but if you are unsure, better to over inform rather than under inform.
Incidentally, very few controllers read the AIM. The 7110.65 takes precedence, and I’ve actually had a supervisor yell at me for referring to the AIM once. I know, I know.
So, legally, it *should* be done. In practice? Unnecessary and I preferred that it not be done when I was working. | In the US...
Under radar contact the leaving level phraseology is not expected nor needed by ATC. What they do need is you tell them what altitude you are at (plus climbing/descend to) when you check in.
The leaving level is mandatory when flying without radar contact.
But AIM tells us to do it anyways.
I listened in nearly 100 hours of recent flying (Premier 1 Driver on youtube), and he never uses leaving level, ATC never asks him to. Other pilots don't use it either.
It is confusing because the AIM teaches us to do it, as well as my instructor did when I got my IFR rating. And it used to be SOP even in radar contact a long time ago.
I'm PPSEL IFR USA. But I haven't flown in 15 years.
Ok, I can't add a comment to user331's answer which conflicts with mine, so let me ask here.
Go out and listen to tens and tens of hours of ATC comms.
You will find out that what's being done is reading back the descent clearance.
When the descent is immediate that creates the impression that the purpose of the readback is to confirm leaving that level, but when its a PD or a descent with a constraint that can be delayed, you will find the pilot doesn't come back and informs leaving later.
So what I said matches real world actions.
If ATC wanted us to report actually leaving the altitude, they would be chastizing every body for not reporting when the altitude change is delayed. The practical reason is simple, under radar contact ATC can see your descent on radar. Without radar contact its a very different deal, ATC cannot see your transponder altitude so they cannot confirm you are descending, vacating your original altitude so actual confirmation is required. |
341,535 | I have two dns server (1dns, 2dns) when the 1st dns is not be able to resolve the query it has to query the 2nd dns but it is important that the source ip of the query 1dns-2dns is the same to the 1st dns ip. | 2011/12/16 | [
"https://serverfault.com/questions/341535",
"https://serverfault.com",
"https://serverfault.com/users/104333/"
] | I've very recently done this for an internal DNS Solution.
Here's how it works. We've got 2 DNS servers. They both run PowerDNS and PowerDNS-Recursor.
They use Postgres-9.1 as the backend, and there is native Postgresql Hot-standby replication occurring between the "master" and "standby".
PowerDNS on each server looks at localhost for it's database connection.
PowerDNS's recursors are told to look at Google's Public DNS for the next hop in recursion.
There's a replication check script also, which updates a Timestamp in a table, then checks it on the standby (but that's just for my OCD monitoring style).
All the documentation on how this works is actually really well listed on the [PDNS website](http://doc.powerdns.com/replication.html). I'm not going to copypasta my configs verbatim for you, because well, you need to learn how to do this for yourself. | Basically there are two ways. Either make your script so that they send changes to both your master and slave server databases or use the master/slave configuration combined with pdns\_control in order to send/retrieve updates from specific zones.
There is more detailed [documentation](http://doc.powerdns.com/replication.html) on this available on the PowerDNS website. |
68,877 | Assalamu Alaikum!
My mother was one time advising me not to spend to much time in the bathroom and was mocking me that I spend hours just rubbing my feet during wudhu.and she also said that dont close the tap again and again during wudhu and I laughed loudly at this. Would this be regarded as Kufr ? Or mocking wudhu or islam ? | 2021/05/27 | [
"https://islam.stackexchange.com/questions/68877",
"https://islam.stackexchange.com",
"https://islam.stackexchange.com/users/44531/"
] | The third person's relation to the woman is not specified. He only has to be her mahram. It could be her any mahram. | The woman must be accompanied by a male mahram in the company of a non-mahram who will act as her guardian |
68,877 | Assalamu Alaikum!
My mother was one time advising me not to spend to much time in the bathroom and was mocking me that I spend hours just rubbing my feet during wudhu.and she also said that dont close the tap again and again during wudhu and I laughed loudly at this. Would this be regarded as Kufr ? Or mocking wudhu or islam ? | 2021/05/27 | [
"https://islam.stackexchange.com/questions/68877",
"https://islam.stackexchange.com",
"https://islam.stackexchange.com/users/44531/"
] | The third person's relation to the woman is not specified. He only has to be her mahram. It could be her any mahram. | Yes it would best to have a mahram with you a male to be safe to keep track on what’s going on |
17,219 | Around a year ago, I moved to the U.S with my spouse and we both started working at tech companies here. Coming from a very different country, we were at first surprised at some behaviours we encountered that made us feel unwelcome.
After discussing this with some friends in similar situations, we realized that this probably wasn't a personal issue, but rather a cultural difference we had to get used too.
Specifically, the issue that struck us most is that employees tend to "keep to themselves", for instance:
* If other team mates are in need of assistance or guidance, it is not voluntarily offered, and even when asked, it seems people leave their own task rather begrudgingly.
* Inquiries on others progress isn't really done, even when the that knowledge would help the team as a whole progress.
* This is relatively little room for "Out of the box" thinking - people are expected to concentrate only on their given task, and it seems polite suggestions for changes are not as well accepted here.
* Eating lunch alone is common. I was used to lunch being a opportunity for team bonding, and skipping lunch (even if you weren't hungry) was considered very anti-social.
So, although we are getting used to the culture difference, it does extract a toll, and I was wondering if anyone here has encountered something similar. In your experience:
* Are the above behaviours indeed part of standard workplace culture in the
U.S.?
* How would you suggest foreigners best adapt to this culture
change? | 2013/12/09 | [
"https://workplace.stackexchange.com/questions/17219",
"https://workplace.stackexchange.com",
"https://workplace.stackexchange.com/users/-1/"
] | >
> Are the above behaviours indeed part of standard workplace culture in
> the U.S.?
>
>
>
Not in my experience, no.
While I have worked with a few companies having a few of those attributes, over the years I've come to the conclusion that **there is no standard workplace culture in the US**.
I've worked at many startups, and large multi-national corporations. I've worked in the retail, software, and financial sectors. I've worked in newer companies and companies that have been around for many years. No two of them are alike.
I think what you are seeing can be ascribed to **company culture** rather than overall US workplace culture. If you browse around some of the questions about US companies here at workplace.stackexchange, I think you'll quickly see that there is a wide array of experiences represented. I know for me, I've worked at US companies with a wide variety of cultures.
I've worked at companies where everyone felt like they were on the same page every day. Assistance was gladly given as a matter of course.
I've worked at companies where everyone had a strong sense of what others were doing, how they were progressing, and where they were stalling.
I've worked at a company where "out of the box thinking" was expected (almost demanded) of everyone, on a regular basis.
I've worked at a few companies where folks ate together virtually every day, and one where everyone at the company ate at a particular restaurant together every single Friday.
I suggest you consider the possibility that your particular company doesn't represent the vast entirety of the US Workplace. And I suggest that you try to slowly help your company's culture change to something you like more. It's rather difficult to enact change as a single individual in a large corporation (since that company's culture is usually born from the top), but if enough individuals work together, change can happen.
Perhaps you can start by inviting some of your colleagues out to lunch. There you can talk about the company - what you like and what you don't like. And perhaps eating lunch together can become a regular thing among a growing group of friends. It's a start. | This is true some of the time, but not always.
I worked with a government contractor on a military project where lunch often involved filling up two or three cars with coworkers and terrorizing some hole in the wall restaurant. This was a very social group and assistance flowed freely among all the parties.
I started work for another company some time later in which it two weeks for anyone to 'thaw' - I realized I was overkill for what most people in the group did. While progress reports within the project were updated weekly, people working on unrelated projects had little to talk about.
I haven't seen much objection to 'out of box thinking', but little interest in it either. I've tended to drive people crazy 'thinking outside the box', the evidence just on this board is hard to miss.
This is probably due to the particular site you're at - different kinds of organizations have different habits. |
17,219 | Around a year ago, I moved to the U.S with my spouse and we both started working at tech companies here. Coming from a very different country, we were at first surprised at some behaviours we encountered that made us feel unwelcome.
After discussing this with some friends in similar situations, we realized that this probably wasn't a personal issue, but rather a cultural difference we had to get used too.
Specifically, the issue that struck us most is that employees tend to "keep to themselves", for instance:
* If other team mates are in need of assistance or guidance, it is not voluntarily offered, and even when asked, it seems people leave their own task rather begrudgingly.
* Inquiries on others progress isn't really done, even when the that knowledge would help the team as a whole progress.
* This is relatively little room for "Out of the box" thinking - people are expected to concentrate only on their given task, and it seems polite suggestions for changes are not as well accepted here.
* Eating lunch alone is common. I was used to lunch being a opportunity for team bonding, and skipping lunch (even if you weren't hungry) was considered very anti-social.
So, although we are getting used to the culture difference, it does extract a toll, and I was wondering if anyone here has encountered something similar. In your experience:
* Are the above behaviours indeed part of standard workplace culture in the
U.S.?
* How would you suggest foreigners best adapt to this culture
change? | 2013/12/09 | [
"https://workplace.stackexchange.com/questions/17219",
"https://workplace.stackexchange.com",
"https://workplace.stackexchange.com/users/-1/"
] | >
> Are the above behaviours indeed part of standard workplace culture in
> the U.S.?
>
>
>
Not in my experience, no.
While I have worked with a few companies having a few of those attributes, over the years I've come to the conclusion that **there is no standard workplace culture in the US**.
I've worked at many startups, and large multi-national corporations. I've worked in the retail, software, and financial sectors. I've worked in newer companies and companies that have been around for many years. No two of them are alike.
I think what you are seeing can be ascribed to **company culture** rather than overall US workplace culture. If you browse around some of the questions about US companies here at workplace.stackexchange, I think you'll quickly see that there is a wide array of experiences represented. I know for me, I've worked at US companies with a wide variety of cultures.
I've worked at companies where everyone felt like they were on the same page every day. Assistance was gladly given as a matter of course.
I've worked at companies where everyone had a strong sense of what others were doing, how they were progressing, and where they were stalling.
I've worked at a company where "out of the box thinking" was expected (almost demanded) of everyone, on a regular basis.
I've worked at a few companies where folks ate together virtually every day, and one where everyone at the company ate at a particular restaurant together every single Friday.
I suggest you consider the possibility that your particular company doesn't represent the vast entirety of the US Workplace. And I suggest that you try to slowly help your company's culture change to something you like more. It's rather difficult to enact change as a single individual in a large corporation (since that company's culture is usually born from the top), but if enough individuals work together, change can happen.
Perhaps you can start by inviting some of your colleagues out to lunch. There you can talk about the company - what you like and what you don't like. And perhaps eating lunch together can become a regular thing among a growing group of friends. It's a start. | I'd say you're right not to take it personally, but there isn't a general rule on corporate culture in tech. Each company, and even each group with in a company has a different character, and it's helpful to keep the eyes and mind open to see what the culture in your company/group is rather than try to find a generalization that applies to all of the US.
I'll offer the following rules of thumb:
* Over the years, I've seen more and more sensitivity to eating limitations - so communal bonding over food is in transition. I've had many social work groups form up around a common love of food, but not necessarily a nearly-compulsory all-team eating thing.
* Also - depending on locale - commuter patterns have a strong influence on eating and drinking together. In some areas, many people will go for a very short lunch and skip after work drinks in favor of beating the commute. Particularly in high day-care situations, the rigorous rules of after school care and parent pickup don't leave much slack.
* There's definitely a hesitancy in some offices regarding alcohol and improper use of alcohol. The US patterns of alcohol consumption can make it a work taboo. Being a lady who likes her one glass of wine at lunch, I learned at one company that I should always take my German friend with me. He'd order a beer, everyone who say "oh, he's German, it's OK" and I'd get in my glass of wine. :)
* Sometimes team bonding occurs over sports - many people will walk or run at breakfast or lunch and informal packs build up around this. Be on the lookout. Also - look for sports groups like basketball, football (the kind you throw), soccer (aka football) and baseball.
Mileage varies - but in some styles of American culture, people can be very private about their status. What would be "sharing" in one culture is seen as "burdening others" in another. This is by no means a universal rule, and in fact some styles of corporate sharing deliberately seek to break down this idea - like Scrums - which focus on "what are you up to? what's blocking your progress?" in an effort to get teams to share more.
A thing to watch for is what role the boss plays in the hierarchy - is this an "everyone shares with the boss" culture or a "help each other first" culture? There's no one rule, so it's useful to get a sense of how status is shared. Similarly, I'd say that every company strives to be innovative, but the patterns for how innovation occurs and is acted upon are by no means universal.
Decision making and information sharing often develop with the history of the company - each company models itself in a pattern built around it's core business and what it's taken to be successful. Changing culture isn't easy, so a company may have very traditional decision making patterns that don't seem easy or obvious in a modern world... |
53,408 | For a fantasy photo project I would like to create a ghostly atmosphere. What I have in mind is a scene with 2 characters, one of them is "real", so will be completely visible, and the other is a ghost or phantom, and would be more of a shadowy figure on the picture, coming from one side behind the other character and leaving on the other side.
Shall I try a long exposure time, with one character staying still and the other quickly passing through? I'm just afraid it will all be blurry, since my main character will be wearing light colors while the ghostly figure will be wearing dark clothes (possibly a long black cloak or something similar).
I'm working with a Sony A33, a basic 18-55mm and a 50mm 1.8.
Thanks for your help! | 2014/08/12 | [
"https://photo.stackexchange.com/questions/53408",
"https://photo.stackexchange.com",
"https://photo.stackexchange.com/users/31755/"
] | Exactly as you say, a long exposure will do the trick... You should use a filter if you are shooting at daytime, otherwise you will perhaps need to compensate the exposure in postprocessing... Your subject (the real one) needs to be very steady so it is sharp while the ghost who is moving will be blurred... Good luck! P.S.: tripod is a must! | I'd suggest combining a long exposure with flash/strobe if you have access to it. This will give you a sharp exposure of the non-ghostly subject. You'll still need to get them to sit still but the result will be much sharper than just using ambient light.
Alternatively if your camera supports it you might be able to double expose a frame. A long exposure for the ghost (using a ND filter if needed) and then a short second exposure with the subject in the frame. If you set up the camera on a tripod (or some sort of support - a table, beanbag, etc.) you should be able to get good results using a double exposure. |
53,408 | For a fantasy photo project I would like to create a ghostly atmosphere. What I have in mind is a scene with 2 characters, one of them is "real", so will be completely visible, and the other is a ghost or phantom, and would be more of a shadowy figure on the picture, coming from one side behind the other character and leaving on the other side.
Shall I try a long exposure time, with one character staying still and the other quickly passing through? I'm just afraid it will all be blurry, since my main character will be wearing light colors while the ghostly figure will be wearing dark clothes (possibly a long black cloak or something similar).
I'm working with a Sony A33, a basic 18-55mm and a 50mm 1.8.
Thanks for your help! | 2014/08/12 | [
"https://photo.stackexchange.com/questions/53408",
"https://photo.stackexchange.com",
"https://photo.stackexchange.com/users/31755/"
] | Exactly as you say, a long exposure will do the trick... You should use a filter if you are shooting at daytime, otherwise you will perhaps need to compensate the exposure in postprocessing... Your subject (the real one) needs to be very steady so it is sharp while the ghost who is moving will be blurred... Good luck! P.S.: tripod is a must! | 
This is two exposures combined. Both the "ghost" walking across the street and the "ghost" sitting on the bench are the same person in different costuming.
[**larger size**](https://i.stack.imgur.com/ROykm.jpg)
If you want one person to be a "non-ghost", they would need to sit perfectly still in the same pose for both exposures.
In this one the "ghost" behind the bar was in only one exposure of a two exposure HDR shot. It really needs to be viewed at full size to see the transparency of the bartender.
[**larger size**](https://i.stack.imgur.com/vkbEy.jpg) |
53,408 | For a fantasy photo project I would like to create a ghostly atmosphere. What I have in mind is a scene with 2 characters, one of them is "real", so will be completely visible, and the other is a ghost or phantom, and would be more of a shadowy figure on the picture, coming from one side behind the other character and leaving on the other side.
Shall I try a long exposure time, with one character staying still and the other quickly passing through? I'm just afraid it will all be blurry, since my main character will be wearing light colors while the ghostly figure will be wearing dark clothes (possibly a long black cloak or something similar).
I'm working with a Sony A33, a basic 18-55mm and a 50mm 1.8.
Thanks for your help! | 2014/08/12 | [
"https://photo.stackexchange.com/questions/53408",
"https://photo.stackexchange.com",
"https://photo.stackexchange.com/users/31755/"
] | Exactly as you say, a long exposure will do the trick... You should use a filter if you are shooting at daytime, otherwise you will perhaps need to compensate the exposure in postprocessing... Your subject (the real one) needs to be very steady so it is sharp while the ghost who is moving will be blurred... Good luck! P.S.: tripod is a must! | It depends on whether you want the ghost to appear as if it's moving or is still. If you want it to look like it's moving then use long exposure & let the ghost move and use a flash on the normal person so they would get propper exposure. If you want the ghost to appear as if it's just standing there then you can either have soft edges & ghostly transparency by using long exposure & a flash on the human & have the ghost try to stand still during the exposure but not too still or if you want to have a ghost with sharp edges yet ghost transparency you can use two bursts of flash, the first one you'd fire on the ghost & remove the ghost from the scene & then fire the second flash on the human when the exposure is about to end. You can experiment with the last idea depending on the area of the set, for example you might need to fire the flash for the ghost when the human is not on the set, then bring in the human & remove the ghost & then fire the flash on the human. There are several ways that you can try that would produce several outcomes depending on your exact needs, but for this set up just get the ghost to move slowly, then bring in the human fast enough so they don't show, especially if you want the ghost to appear as if it's passing behind the human, & then trigger the flash when the ghost is out of the frame. |
53,408 | For a fantasy photo project I would like to create a ghostly atmosphere. What I have in mind is a scene with 2 characters, one of them is "real", so will be completely visible, and the other is a ghost or phantom, and would be more of a shadowy figure on the picture, coming from one side behind the other character and leaving on the other side.
Shall I try a long exposure time, with one character staying still and the other quickly passing through? I'm just afraid it will all be blurry, since my main character will be wearing light colors while the ghostly figure will be wearing dark clothes (possibly a long black cloak or something similar).
I'm working with a Sony A33, a basic 18-55mm and a 50mm 1.8.
Thanks for your help! | 2014/08/12 | [
"https://photo.stackexchange.com/questions/53408",
"https://photo.stackexchange.com",
"https://photo.stackexchange.com/users/31755/"
] | Exactly as you say, a long exposure will do the trick... You should use a filter if you are shooting at daytime, otherwise you will perhaps need to compensate the exposure in postprocessing... Your subject (the real one) needs to be very steady so it is sharp while the ghost who is moving will be blurred... Good luck! P.S.: tripod is a must! | To achieve what you describe requires 3 separate exposures - these can all be achieved within the same frame with due care.
* To get a clear but ghostly image the ghost either needs to remain in one place for part of the exposure or be flash-lit at the point where it needs to be clear.
* To get a blurred moving ghosts image the ghost needs to move through the frame.
* The background is usually lit throughout the frame.
The super enthused could use "bulb" and turn lighting on and off and move the ghosts etc in dark periods. This would allow eg ghosts to move to a location, position themselves steadily and then have lights turned on.
The background will also be lit by any flash used to highlight the stationary ghost and/or the background can be lit with a flash when the ghost is absent to increase background contrast. Having an independently operated flash able to be used as and when required would greatly ease creating desired effects. If camera controlled std flash is used then (usual) front curtain synchronised flash will lead to trails in front of the ghost and rear curtain flash will lead to trails behind the ghost.
In the images below various effects are noted. Some of these were intentional and some were happenstance. Ghost shooting often requires both trail and error AND intelligent planning and analysis of what you see and why to achieve a desired effect. The various effects on the left hand character in the right half of the final image below [I resemble that] were largely not planned and some were somewhat unexpected (eg variations in shirt transperancy and variation in 'tatoo' effects on arms. While these are obviously explicable in terms of relative lighting levels, being aware that such things happen will (hopefully) help in achieving the desired effects.
---
The image below demonstrates some of these concepts and also shows some potential problems which need to be addressed. This was taken at ISO100 f/3.5, 15 seconds with no flash. It can be seen that the smoothness of motion of the moving ghost affects how distinct the character is. If the left hand character had walked slowly across the scene, paused for say 20% of the time at some point and then walked on, you'd have both a trail and a distinct ghost. If the pause was at the last portion of the exposure you'd have a trail leading up to the ghost.
For 'extra points' and with enough exposure time a single ghost could run from point to point and then pause at various points (rock steady ptm] of course and then more on. Slow motion would leave a trail between several more distinct ghosts. Fast motion would leave no trail (see sitting ghosts).
Ghosts of Escondido. [**Larger version here**](https://i.stack.imgur.com/wwUOm.jpg)
The two sitting 'ghosts' simply stood up and walked away part way through the exposure. Do this rapidly enough and it is not obvious that the 'ghost' has moved. I've had a peer at the larger version and there is no readily apparent image from the departing ghosts.
The ghost at left simply moved slightly in a series of 'jerks' during the exposure - steady motion would leave a blur.
Closer-up of 3 seated figures. Figure at right is NOT a ghost but relative lighting has washed out contrast. Ghostiness" can be adjusted by percent of time that ghost is present.
I'm the right hand of the two seated ghosts.
---
**Ghost with flash**
This is a 2 second exposure with rear curtain flash.
The Police car almost didn't get included (when the flash is synced to a long shutter speed it tales luck and practice to get things right).
They didn't come back :-)
The top portion is a blowup of the left hand middle edge.
[Larger version here](https://i.stack.imgur.com/wMnN9.jpg)
---
**Walking Ghost, rear curtain flash**
Same location.
My excuse for looking like that is it's 2:40am in a cold wet winter morning :-).
4 seconds, f/5.,6, ISO 100, rear curtain sync.
No obvious ghost motion.
Note car tail-light - a ghost vehicle has transited the picture but left no impression of the actual car.
Service station lighting serves to vary the degree of ghostliness.
Flash at end of frame highlights ghost.
[Larger versioin hgere](https://i.stack.imgur.com/sSnly.jpg)
**Without a flash** the ghost is almost unseen in the same conditions (at far right)
**Ghost trails:**
Here the ghost has moved slowly enough toi leave a atrail behgind, but the effectis hardly pleasing. More frontr lighting would make the moving ghost more distinct relative to the background and make the trail more solid for a given speed of movement.
Note the dotted lines of right at rear - these are from indicators od cars turning into (out of) the street behind. They were not driving on the grass despite appearances.
[Larger version](https://i.stack.imgur.com/1NdgZ.jpg)
---
Background / foreground lighting:
The variation between background and foreground at each point in the picture can make an immense difference to what is seen. Image below is 1.5 seconds, f/16, ISo 400 in each case.
In the left half image below the left side of the left hand character has (not surprisingly) no apparent ghost effect as the flash lit character is set off against an essentially black background. The rh side of the character is nicely ghosted in the white shirt area while the black trousers essentially vanish due to the illuminated doorpanels behind. The young woman has variable bands of ghostly effect with a "running man" fire exit logo tastefully stamped on her head (there's no accounting for what ghosts will do)
and various other light / dark and dark / light combinations leading to a range of effects.
In the right half image the left side character (which happens to be me) displays a range of interesting variations. The shirt which is flash illuminated varies from almost wholly opaque to about 50% transparent in a manner which is non-intuitive and the carpet pattern tattoos on the arms are seen through the arm (left of image) and on the arm (right of image).
 |
53,408 | For a fantasy photo project I would like to create a ghostly atmosphere. What I have in mind is a scene with 2 characters, one of them is "real", so will be completely visible, and the other is a ghost or phantom, and would be more of a shadowy figure on the picture, coming from one side behind the other character and leaving on the other side.
Shall I try a long exposure time, with one character staying still and the other quickly passing through? I'm just afraid it will all be blurry, since my main character will be wearing light colors while the ghostly figure will be wearing dark clothes (possibly a long black cloak or something similar).
I'm working with a Sony A33, a basic 18-55mm and a 50mm 1.8.
Thanks for your help! | 2014/08/12 | [
"https://photo.stackexchange.com/questions/53408",
"https://photo.stackexchange.com",
"https://photo.stackexchange.com/users/31755/"
] | I'd suggest combining a long exposure with flash/strobe if you have access to it. This will give you a sharp exposure of the non-ghostly subject. You'll still need to get them to sit still but the result will be much sharper than just using ambient light.
Alternatively if your camera supports it you might be able to double expose a frame. A long exposure for the ghost (using a ND filter if needed) and then a short second exposure with the subject in the frame. If you set up the camera on a tripod (or some sort of support - a table, beanbag, etc.) you should be able to get good results using a double exposure. | 
This is two exposures combined. Both the "ghost" walking across the street and the "ghost" sitting on the bench are the same person in different costuming.
[**larger size**](https://i.stack.imgur.com/ROykm.jpg)
If you want one person to be a "non-ghost", they would need to sit perfectly still in the same pose for both exposures.
In this one the "ghost" behind the bar was in only one exposure of a two exposure HDR shot. It really needs to be viewed at full size to see the transparency of the bartender.
[**larger size**](https://i.stack.imgur.com/vkbEy.jpg) |
53,408 | For a fantasy photo project I would like to create a ghostly atmosphere. What I have in mind is a scene with 2 characters, one of them is "real", so will be completely visible, and the other is a ghost or phantom, and would be more of a shadowy figure on the picture, coming from one side behind the other character and leaving on the other side.
Shall I try a long exposure time, with one character staying still and the other quickly passing through? I'm just afraid it will all be blurry, since my main character will be wearing light colors while the ghostly figure will be wearing dark clothes (possibly a long black cloak or something similar).
I'm working with a Sony A33, a basic 18-55mm and a 50mm 1.8.
Thanks for your help! | 2014/08/12 | [
"https://photo.stackexchange.com/questions/53408",
"https://photo.stackexchange.com",
"https://photo.stackexchange.com/users/31755/"
] | To achieve what you describe requires 3 separate exposures - these can all be achieved within the same frame with due care.
* To get a clear but ghostly image the ghost either needs to remain in one place for part of the exposure or be flash-lit at the point where it needs to be clear.
* To get a blurred moving ghosts image the ghost needs to move through the frame.
* The background is usually lit throughout the frame.
The super enthused could use "bulb" and turn lighting on and off and move the ghosts etc in dark periods. This would allow eg ghosts to move to a location, position themselves steadily and then have lights turned on.
The background will also be lit by any flash used to highlight the stationary ghost and/or the background can be lit with a flash when the ghost is absent to increase background contrast. Having an independently operated flash able to be used as and when required would greatly ease creating desired effects. If camera controlled std flash is used then (usual) front curtain synchronised flash will lead to trails in front of the ghost and rear curtain flash will lead to trails behind the ghost.
In the images below various effects are noted. Some of these were intentional and some were happenstance. Ghost shooting often requires both trail and error AND intelligent planning and analysis of what you see and why to achieve a desired effect. The various effects on the left hand character in the right half of the final image below [I resemble that] were largely not planned and some were somewhat unexpected (eg variations in shirt transperancy and variation in 'tatoo' effects on arms. While these are obviously explicable in terms of relative lighting levels, being aware that such things happen will (hopefully) help in achieving the desired effects.
---
The image below demonstrates some of these concepts and also shows some potential problems which need to be addressed. This was taken at ISO100 f/3.5, 15 seconds with no flash. It can be seen that the smoothness of motion of the moving ghost affects how distinct the character is. If the left hand character had walked slowly across the scene, paused for say 20% of the time at some point and then walked on, you'd have both a trail and a distinct ghost. If the pause was at the last portion of the exposure you'd have a trail leading up to the ghost.
For 'extra points' and with enough exposure time a single ghost could run from point to point and then pause at various points (rock steady ptm] of course and then more on. Slow motion would leave a trail between several more distinct ghosts. Fast motion would leave no trail (see sitting ghosts).
Ghosts of Escondido. [**Larger version here**](https://i.stack.imgur.com/wwUOm.jpg)
The two sitting 'ghosts' simply stood up and walked away part way through the exposure. Do this rapidly enough and it is not obvious that the 'ghost' has moved. I've had a peer at the larger version and there is no readily apparent image from the departing ghosts.
The ghost at left simply moved slightly in a series of 'jerks' during the exposure - steady motion would leave a blur.
Closer-up of 3 seated figures. Figure at right is NOT a ghost but relative lighting has washed out contrast. Ghostiness" can be adjusted by percent of time that ghost is present.
I'm the right hand of the two seated ghosts.
---
**Ghost with flash**
This is a 2 second exposure with rear curtain flash.
The Police car almost didn't get included (when the flash is synced to a long shutter speed it tales luck and practice to get things right).
They didn't come back :-)
The top portion is a blowup of the left hand middle edge.
[Larger version here](https://i.stack.imgur.com/wMnN9.jpg)
---
**Walking Ghost, rear curtain flash**
Same location.
My excuse for looking like that is it's 2:40am in a cold wet winter morning :-).
4 seconds, f/5.,6, ISO 100, rear curtain sync.
No obvious ghost motion.
Note car tail-light - a ghost vehicle has transited the picture but left no impression of the actual car.
Service station lighting serves to vary the degree of ghostliness.
Flash at end of frame highlights ghost.
[Larger versioin hgere](https://i.stack.imgur.com/sSnly.jpg)
**Without a flash** the ghost is almost unseen in the same conditions (at far right)
**Ghost trails:**
Here the ghost has moved slowly enough toi leave a atrail behgind, but the effectis hardly pleasing. More frontr lighting would make the moving ghost more distinct relative to the background and make the trail more solid for a given speed of movement.
Note the dotted lines of right at rear - these are from indicators od cars turning into (out of) the street behind. They were not driving on the grass despite appearances.
[Larger version](https://i.stack.imgur.com/1NdgZ.jpg)
---
Background / foreground lighting:
The variation between background and foreground at each point in the picture can make an immense difference to what is seen. Image below is 1.5 seconds, f/16, ISo 400 in each case.
In the left half image below the left side of the left hand character has (not surprisingly) no apparent ghost effect as the flash lit character is set off against an essentially black background. The rh side of the character is nicely ghosted in the white shirt area while the black trousers essentially vanish due to the illuminated doorpanels behind. The young woman has variable bands of ghostly effect with a "running man" fire exit logo tastefully stamped on her head (there's no accounting for what ghosts will do)
and various other light / dark and dark / light combinations leading to a range of effects.
In the right half image the left side character (which happens to be me) displays a range of interesting variations. The shirt which is flash illuminated varies from almost wholly opaque to about 50% transparent in a manner which is non-intuitive and the carpet pattern tattoos on the arms are seen through the arm (left of image) and on the arm (right of image).
 | I'd suggest combining a long exposure with flash/strobe if you have access to it. This will give you a sharp exposure of the non-ghostly subject. You'll still need to get them to sit still but the result will be much sharper than just using ambient light.
Alternatively if your camera supports it you might be able to double expose a frame. A long exposure for the ghost (using a ND filter if needed) and then a short second exposure with the subject in the frame. If you set up the camera on a tripod (or some sort of support - a table, beanbag, etc.) you should be able to get good results using a double exposure. |
53,408 | For a fantasy photo project I would like to create a ghostly atmosphere. What I have in mind is a scene with 2 characters, one of them is "real", so will be completely visible, and the other is a ghost or phantom, and would be more of a shadowy figure on the picture, coming from one side behind the other character and leaving on the other side.
Shall I try a long exposure time, with one character staying still and the other quickly passing through? I'm just afraid it will all be blurry, since my main character will be wearing light colors while the ghostly figure will be wearing dark clothes (possibly a long black cloak or something similar).
I'm working with a Sony A33, a basic 18-55mm and a 50mm 1.8.
Thanks for your help! | 2014/08/12 | [
"https://photo.stackexchange.com/questions/53408",
"https://photo.stackexchange.com",
"https://photo.stackexchange.com/users/31755/"
] | It depends on whether you want the ghost to appear as if it's moving or is still. If you want it to look like it's moving then use long exposure & let the ghost move and use a flash on the normal person so they would get propper exposure. If you want the ghost to appear as if it's just standing there then you can either have soft edges & ghostly transparency by using long exposure & a flash on the human & have the ghost try to stand still during the exposure but not too still or if you want to have a ghost with sharp edges yet ghost transparency you can use two bursts of flash, the first one you'd fire on the ghost & remove the ghost from the scene & then fire the second flash on the human when the exposure is about to end. You can experiment with the last idea depending on the area of the set, for example you might need to fire the flash for the ghost when the human is not on the set, then bring in the human & remove the ghost & then fire the flash on the human. There are several ways that you can try that would produce several outcomes depending on your exact needs, but for this set up just get the ghost to move slowly, then bring in the human fast enough so they don't show, especially if you want the ghost to appear as if it's passing behind the human, & then trigger the flash when the ghost is out of the frame. | 
This is two exposures combined. Both the "ghost" walking across the street and the "ghost" sitting on the bench are the same person in different costuming.
[**larger size**](https://i.stack.imgur.com/ROykm.jpg)
If you want one person to be a "non-ghost", they would need to sit perfectly still in the same pose for both exposures.
In this one the "ghost" behind the bar was in only one exposure of a two exposure HDR shot. It really needs to be viewed at full size to see the transparency of the bartender.
[**larger size**](https://i.stack.imgur.com/vkbEy.jpg) |
53,408 | For a fantasy photo project I would like to create a ghostly atmosphere. What I have in mind is a scene with 2 characters, one of them is "real", so will be completely visible, and the other is a ghost or phantom, and would be more of a shadowy figure on the picture, coming from one side behind the other character and leaving on the other side.
Shall I try a long exposure time, with one character staying still and the other quickly passing through? I'm just afraid it will all be blurry, since my main character will be wearing light colors while the ghostly figure will be wearing dark clothes (possibly a long black cloak or something similar).
I'm working with a Sony A33, a basic 18-55mm and a 50mm 1.8.
Thanks for your help! | 2014/08/12 | [
"https://photo.stackexchange.com/questions/53408",
"https://photo.stackexchange.com",
"https://photo.stackexchange.com/users/31755/"
] | To achieve what you describe requires 3 separate exposures - these can all be achieved within the same frame with due care.
* To get a clear but ghostly image the ghost either needs to remain in one place for part of the exposure or be flash-lit at the point where it needs to be clear.
* To get a blurred moving ghosts image the ghost needs to move through the frame.
* The background is usually lit throughout the frame.
The super enthused could use "bulb" and turn lighting on and off and move the ghosts etc in dark periods. This would allow eg ghosts to move to a location, position themselves steadily and then have lights turned on.
The background will also be lit by any flash used to highlight the stationary ghost and/or the background can be lit with a flash when the ghost is absent to increase background contrast. Having an independently operated flash able to be used as and when required would greatly ease creating desired effects. If camera controlled std flash is used then (usual) front curtain synchronised flash will lead to trails in front of the ghost and rear curtain flash will lead to trails behind the ghost.
In the images below various effects are noted. Some of these were intentional and some were happenstance. Ghost shooting often requires both trail and error AND intelligent planning and analysis of what you see and why to achieve a desired effect. The various effects on the left hand character in the right half of the final image below [I resemble that] were largely not planned and some were somewhat unexpected (eg variations in shirt transperancy and variation in 'tatoo' effects on arms. While these are obviously explicable in terms of relative lighting levels, being aware that such things happen will (hopefully) help in achieving the desired effects.
---
The image below demonstrates some of these concepts and also shows some potential problems which need to be addressed. This was taken at ISO100 f/3.5, 15 seconds with no flash. It can be seen that the smoothness of motion of the moving ghost affects how distinct the character is. If the left hand character had walked slowly across the scene, paused for say 20% of the time at some point and then walked on, you'd have both a trail and a distinct ghost. If the pause was at the last portion of the exposure you'd have a trail leading up to the ghost.
For 'extra points' and with enough exposure time a single ghost could run from point to point and then pause at various points (rock steady ptm] of course and then more on. Slow motion would leave a trail between several more distinct ghosts. Fast motion would leave no trail (see sitting ghosts).
Ghosts of Escondido. [**Larger version here**](https://i.stack.imgur.com/wwUOm.jpg)
The two sitting 'ghosts' simply stood up and walked away part way through the exposure. Do this rapidly enough and it is not obvious that the 'ghost' has moved. I've had a peer at the larger version and there is no readily apparent image from the departing ghosts.
The ghost at left simply moved slightly in a series of 'jerks' during the exposure - steady motion would leave a blur.
Closer-up of 3 seated figures. Figure at right is NOT a ghost but relative lighting has washed out contrast. Ghostiness" can be adjusted by percent of time that ghost is present.
I'm the right hand of the two seated ghosts.
---
**Ghost with flash**
This is a 2 second exposure with rear curtain flash.
The Police car almost didn't get included (when the flash is synced to a long shutter speed it tales luck and practice to get things right).
They didn't come back :-)
The top portion is a blowup of the left hand middle edge.
[Larger version here](https://i.stack.imgur.com/wMnN9.jpg)
---
**Walking Ghost, rear curtain flash**
Same location.
My excuse for looking like that is it's 2:40am in a cold wet winter morning :-).
4 seconds, f/5.,6, ISO 100, rear curtain sync.
No obvious ghost motion.
Note car tail-light - a ghost vehicle has transited the picture but left no impression of the actual car.
Service station lighting serves to vary the degree of ghostliness.
Flash at end of frame highlights ghost.
[Larger versioin hgere](https://i.stack.imgur.com/sSnly.jpg)
**Without a flash** the ghost is almost unseen in the same conditions (at far right)
**Ghost trails:**
Here the ghost has moved slowly enough toi leave a atrail behgind, but the effectis hardly pleasing. More frontr lighting would make the moving ghost more distinct relative to the background and make the trail more solid for a given speed of movement.
Note the dotted lines of right at rear - these are from indicators od cars turning into (out of) the street behind. They were not driving on the grass despite appearances.
[Larger version](https://i.stack.imgur.com/1NdgZ.jpg)
---
Background / foreground lighting:
The variation between background and foreground at each point in the picture can make an immense difference to what is seen. Image below is 1.5 seconds, f/16, ISo 400 in each case.
In the left half image below the left side of the left hand character has (not surprisingly) no apparent ghost effect as the flash lit character is set off against an essentially black background. The rh side of the character is nicely ghosted in the white shirt area while the black trousers essentially vanish due to the illuminated doorpanels behind. The young woman has variable bands of ghostly effect with a "running man" fire exit logo tastefully stamped on her head (there's no accounting for what ghosts will do)
and various other light / dark and dark / light combinations leading to a range of effects.
In the right half image the left side character (which happens to be me) displays a range of interesting variations. The shirt which is flash illuminated varies from almost wholly opaque to about 50% transparent in a manner which is non-intuitive and the carpet pattern tattoos on the arms are seen through the arm (left of image) and on the arm (right of image).
 | 
This is two exposures combined. Both the "ghost" walking across the street and the "ghost" sitting on the bench are the same person in different costuming.
[**larger size**](https://i.stack.imgur.com/ROykm.jpg)
If you want one person to be a "non-ghost", they would need to sit perfectly still in the same pose for both exposures.
In this one the "ghost" behind the bar was in only one exposure of a two exposure HDR shot. It really needs to be viewed at full size to see the transparency of the bartender.
[**larger size**](https://i.stack.imgur.com/vkbEy.jpg) |
53,408 | For a fantasy photo project I would like to create a ghostly atmosphere. What I have in mind is a scene with 2 characters, one of them is "real", so will be completely visible, and the other is a ghost or phantom, and would be more of a shadowy figure on the picture, coming from one side behind the other character and leaving on the other side.
Shall I try a long exposure time, with one character staying still and the other quickly passing through? I'm just afraid it will all be blurry, since my main character will be wearing light colors while the ghostly figure will be wearing dark clothes (possibly a long black cloak or something similar).
I'm working with a Sony A33, a basic 18-55mm and a 50mm 1.8.
Thanks for your help! | 2014/08/12 | [
"https://photo.stackexchange.com/questions/53408",
"https://photo.stackexchange.com",
"https://photo.stackexchange.com/users/31755/"
] | To achieve what you describe requires 3 separate exposures - these can all be achieved within the same frame with due care.
* To get a clear but ghostly image the ghost either needs to remain in one place for part of the exposure or be flash-lit at the point where it needs to be clear.
* To get a blurred moving ghosts image the ghost needs to move through the frame.
* The background is usually lit throughout the frame.
The super enthused could use "bulb" and turn lighting on and off and move the ghosts etc in dark periods. This would allow eg ghosts to move to a location, position themselves steadily and then have lights turned on.
The background will also be lit by any flash used to highlight the stationary ghost and/or the background can be lit with a flash when the ghost is absent to increase background contrast. Having an independently operated flash able to be used as and when required would greatly ease creating desired effects. If camera controlled std flash is used then (usual) front curtain synchronised flash will lead to trails in front of the ghost and rear curtain flash will lead to trails behind the ghost.
In the images below various effects are noted. Some of these were intentional and some were happenstance. Ghost shooting often requires both trail and error AND intelligent planning and analysis of what you see and why to achieve a desired effect. The various effects on the left hand character in the right half of the final image below [I resemble that] were largely not planned and some were somewhat unexpected (eg variations in shirt transperancy and variation in 'tatoo' effects on arms. While these are obviously explicable in terms of relative lighting levels, being aware that such things happen will (hopefully) help in achieving the desired effects.
---
The image below demonstrates some of these concepts and also shows some potential problems which need to be addressed. This was taken at ISO100 f/3.5, 15 seconds with no flash. It can be seen that the smoothness of motion of the moving ghost affects how distinct the character is. If the left hand character had walked slowly across the scene, paused for say 20% of the time at some point and then walked on, you'd have both a trail and a distinct ghost. If the pause was at the last portion of the exposure you'd have a trail leading up to the ghost.
For 'extra points' and with enough exposure time a single ghost could run from point to point and then pause at various points (rock steady ptm] of course and then more on. Slow motion would leave a trail between several more distinct ghosts. Fast motion would leave no trail (see sitting ghosts).
Ghosts of Escondido. [**Larger version here**](https://i.stack.imgur.com/wwUOm.jpg)
The two sitting 'ghosts' simply stood up and walked away part way through the exposure. Do this rapidly enough and it is not obvious that the 'ghost' has moved. I've had a peer at the larger version and there is no readily apparent image from the departing ghosts.
The ghost at left simply moved slightly in a series of 'jerks' during the exposure - steady motion would leave a blur.
Closer-up of 3 seated figures. Figure at right is NOT a ghost but relative lighting has washed out contrast. Ghostiness" can be adjusted by percent of time that ghost is present.
I'm the right hand of the two seated ghosts.
---
**Ghost with flash**
This is a 2 second exposure with rear curtain flash.
The Police car almost didn't get included (when the flash is synced to a long shutter speed it tales luck and practice to get things right).
They didn't come back :-)
The top portion is a blowup of the left hand middle edge.
[Larger version here](https://i.stack.imgur.com/wMnN9.jpg)
---
**Walking Ghost, rear curtain flash**
Same location.
My excuse for looking like that is it's 2:40am in a cold wet winter morning :-).
4 seconds, f/5.,6, ISO 100, rear curtain sync.
No obvious ghost motion.
Note car tail-light - a ghost vehicle has transited the picture but left no impression of the actual car.
Service station lighting serves to vary the degree of ghostliness.
Flash at end of frame highlights ghost.
[Larger versioin hgere](https://i.stack.imgur.com/sSnly.jpg)
**Without a flash** the ghost is almost unseen in the same conditions (at far right)
**Ghost trails:**
Here the ghost has moved slowly enough toi leave a atrail behgind, but the effectis hardly pleasing. More frontr lighting would make the moving ghost more distinct relative to the background and make the trail more solid for a given speed of movement.
Note the dotted lines of right at rear - these are from indicators od cars turning into (out of) the street behind. They were not driving on the grass despite appearances.
[Larger version](https://i.stack.imgur.com/1NdgZ.jpg)
---
Background / foreground lighting:
The variation between background and foreground at each point in the picture can make an immense difference to what is seen. Image below is 1.5 seconds, f/16, ISo 400 in each case.
In the left half image below the left side of the left hand character has (not surprisingly) no apparent ghost effect as the flash lit character is set off against an essentially black background. The rh side of the character is nicely ghosted in the white shirt area while the black trousers essentially vanish due to the illuminated doorpanels behind. The young woman has variable bands of ghostly effect with a "running man" fire exit logo tastefully stamped on her head (there's no accounting for what ghosts will do)
and various other light / dark and dark / light combinations leading to a range of effects.
In the right half image the left side character (which happens to be me) displays a range of interesting variations. The shirt which is flash illuminated varies from almost wholly opaque to about 50% transparent in a manner which is non-intuitive and the carpet pattern tattoos on the arms are seen through the arm (left of image) and on the arm (right of image).
 | It depends on whether you want the ghost to appear as if it's moving or is still. If you want it to look like it's moving then use long exposure & let the ghost move and use a flash on the normal person so they would get propper exposure. If you want the ghost to appear as if it's just standing there then you can either have soft edges & ghostly transparency by using long exposure & a flash on the human & have the ghost try to stand still during the exposure but not too still or if you want to have a ghost with sharp edges yet ghost transparency you can use two bursts of flash, the first one you'd fire on the ghost & remove the ghost from the scene & then fire the second flash on the human when the exposure is about to end. You can experiment with the last idea depending on the area of the set, for example you might need to fire the flash for the ghost when the human is not on the set, then bring in the human & remove the ghost & then fire the flash on the human. There are several ways that you can try that would produce several outcomes depending on your exact needs, but for this set up just get the ghost to move slowly, then bring in the human fast enough so they don't show, especially if you want the ghost to appear as if it's passing behind the human, & then trigger the flash when the ghost is out of the frame. |
162,590 | I am planning on getting a new CPU and am looking at a quad core i5.
The reason for the quad-core is that I generally multi-task a lot for example running Visual Studio, Eclipse Aptana, Photoshop, Lightroom and lots of Chrome browsers all at once.
1. I am wondering if it is possible to allocate certain processes such as Visual Studio permanently to use a particular core, and is there a tool better than Windows Task Manager to achieve this?
2. Will this give me a snappier multi-tasking experience or will I not notice the effects?
3. I am also planning on moving to 8GB from 3GB as I experience severe thrashing after a couple hours of web development with multiple IDE's open and using Chrome's developer tools. Will the additional RAM be enough, or do I need a faster CPU? (currently running Core 2 Duo E6750 @ 2.66ghz) | 2010/07/12 | [
"https://superuser.com/questions/162590",
"https://superuser.com",
"https://superuser.com/users/23916/"
] | Generally you will not notice the effects of putting particular processes on particular cores as Windows is generally pretty good at scheduling items between cores, especially on Windows 7 which was designed with this kind of thing in mind.
I have found that in general a busy task will spend most (generally >60% for normal apps and >95% for single threaded games) of it's time on one core and Windows will schedule other tasks on other cores as things get busier so I wouldn't worry about it. I seem to remember reading that windows 7 is able to tell which cores are "preferred" in a system, so on an Intel system that uses their [Turbo Boost](http://www.intel.com/technology/turboboost/) feature (which uses the activity on the first core to tell if it needs to boost) and Hyperthreading then Windows will tend to schedule single threaded tasks on the first core and then multithreaded tasks will preferentially be assigned to the "real" cores before the hyperthreaded "virtual" cores. I've seen this at work on my i7 (quad-core, 8 hyperthreaded cores) and it works pretty well with games almost exclusively using the first core and then moderate use on the alternate "real" cores.
The only time that I find specifying the affinity to be useful is when watching video using certain media players that are multiprocessor friendly but seem to have timing issues. [Mediaplayer Classic Hometheater Edition](http://mpc-hc.sourceforge.net/) seems to "jump" quite a lot when you start skipping forward in a video, presumably because it is using multiple threads to decode and they aren't well synchronised across cores and in that case setting it to only use one cpu stops the jumping.
In case you do need to change CPU affinity there are a couple of tools:
[Runfirst](http://www.activeplus.com/us/freeware/runfirst/) helps to fix older programs by making sure they only run on the first cpu available in the system.
[This review](http://www.tomshardware.com/reviews/bang-dual-processing-buck,815.html) on Toms Hardware has a tool that will automatically reassign task affinities for you, but the link they have seems to be broken, and it appears to be a bit difficult to find these days. I think this program has to be kept running all the time you want it to be assigning affinities. Looks like you might be able to get it [here](http://www.app-stick.com/appDetail.php?appid=taskassign)
In general though I do not think you will see any real benefit to manually assigning affinities and I think the practise has pretty much died out as software has gotten better.
I would honestly expect that 8GB of ram would be more than enough to suit your needs, but I've no real experience using the tools you are using. I can say that on a 6GB system I have never had the system feel slow due to hard drive thrashing when I've been running multiple virtual machines and an IDE (eclipse) running... | Assigning CPU affinities to specific executables is a bad idea. Setting affinity on a process doesn't reserve a CPU for that process you specify, locking out all other processes from that CPU. It just says that that process can only use the designated CPU.
That's a problem because there are far more processes needing CPU time than the ones you're normally aware of. If you use affinities to bind a process to say, CPU 0, and something else is using CPU 0 when your process happens to need CPU, your process can't run at all until the something else is done with CPU 0.
It's much better to run somewhere than nowhere, and running nowhere is a common result of setting affinities.
Another horrible result of setting affinity on a process to a single CPU is that you confine all of that process's threads to the one CPU. Thereby killing any performance advantage that multithreading might have had.
In short, just let the Windows scheduler do its thing. The fewer options you let it have, the poorer a job it can do. |
162,590 | I am planning on getting a new CPU and am looking at a quad core i5.
The reason for the quad-core is that I generally multi-task a lot for example running Visual Studio, Eclipse Aptana, Photoshop, Lightroom and lots of Chrome browsers all at once.
1. I am wondering if it is possible to allocate certain processes such as Visual Studio permanently to use a particular core, and is there a tool better than Windows Task Manager to achieve this?
2. Will this give me a snappier multi-tasking experience or will I not notice the effects?
3. I am also planning on moving to 8GB from 3GB as I experience severe thrashing after a couple hours of web development with multiple IDE's open and using Chrome's developer tools. Will the additional RAM be enough, or do I need a faster CPU? (currently running Core 2 Duo E6750 @ 2.66ghz) | 2010/07/12 | [
"https://superuser.com/questions/162590",
"https://superuser.com",
"https://superuser.com/users/23916/"
] | Generally you will not notice the effects of putting particular processes on particular cores as Windows is generally pretty good at scheduling items between cores, especially on Windows 7 which was designed with this kind of thing in mind.
I have found that in general a busy task will spend most (generally >60% for normal apps and >95% for single threaded games) of it's time on one core and Windows will schedule other tasks on other cores as things get busier so I wouldn't worry about it. I seem to remember reading that windows 7 is able to tell which cores are "preferred" in a system, so on an Intel system that uses their [Turbo Boost](http://www.intel.com/technology/turboboost/) feature (which uses the activity on the first core to tell if it needs to boost) and Hyperthreading then Windows will tend to schedule single threaded tasks on the first core and then multithreaded tasks will preferentially be assigned to the "real" cores before the hyperthreaded "virtual" cores. I've seen this at work on my i7 (quad-core, 8 hyperthreaded cores) and it works pretty well with games almost exclusively using the first core and then moderate use on the alternate "real" cores.
The only time that I find specifying the affinity to be useful is when watching video using certain media players that are multiprocessor friendly but seem to have timing issues. [Mediaplayer Classic Hometheater Edition](http://mpc-hc.sourceforge.net/) seems to "jump" quite a lot when you start skipping forward in a video, presumably because it is using multiple threads to decode and they aren't well synchronised across cores and in that case setting it to only use one cpu stops the jumping.
In case you do need to change CPU affinity there are a couple of tools:
[Runfirst](http://www.activeplus.com/us/freeware/runfirst/) helps to fix older programs by making sure they only run on the first cpu available in the system.
[This review](http://www.tomshardware.com/reviews/bang-dual-processing-buck,815.html) on Toms Hardware has a tool that will automatically reassign task affinities for you, but the link they have seems to be broken, and it appears to be a bit difficult to find these days. I think this program has to be kept running all the time you want it to be assigning affinities. Looks like you might be able to get it [here](http://www.app-stick.com/appDetail.php?appid=taskassign)
In general though I do not think you will see any real benefit to manually assigning affinities and I think the practise has pretty much died out as software has gotten better.
I would honestly expect that 8GB of ram would be more than enough to suit your needs, but I've no real experience using the tools you are using. I can say that on a 6GB system I have never had the system feel slow due to hard drive thrashing when I've been running multiple virtual machines and an IDE (eclipse) running... | Jamie is correct BUT, there are some mainstream programs that run much better on a single thread like AutoCAD and I do assign it to a single core and it runs faster with less lags. That being said there are other components of AutoCAd such as printing that will then seem a bit slower doing this as those processes may lend themselves to multi-core functionality. I am sorry to say that the software is not well optimized for multi-core systems still!!! |
162,590 | I am planning on getting a new CPU and am looking at a quad core i5.
The reason for the quad-core is that I generally multi-task a lot for example running Visual Studio, Eclipse Aptana, Photoshop, Lightroom and lots of Chrome browsers all at once.
1. I am wondering if it is possible to allocate certain processes such as Visual Studio permanently to use a particular core, and is there a tool better than Windows Task Manager to achieve this?
2. Will this give me a snappier multi-tasking experience or will I not notice the effects?
3. I am also planning on moving to 8GB from 3GB as I experience severe thrashing after a couple hours of web development with multiple IDE's open and using Chrome's developer tools. Will the additional RAM be enough, or do I need a faster CPU? (currently running Core 2 Duo E6750 @ 2.66ghz) | 2010/07/12 | [
"https://superuser.com/questions/162590",
"https://superuser.com",
"https://superuser.com/users/23916/"
] | Assigning CPU affinities to specific executables is a bad idea. Setting affinity on a process doesn't reserve a CPU for that process you specify, locking out all other processes from that CPU. It just says that that process can only use the designated CPU.
That's a problem because there are far more processes needing CPU time than the ones you're normally aware of. If you use affinities to bind a process to say, CPU 0, and something else is using CPU 0 when your process happens to need CPU, your process can't run at all until the something else is done with CPU 0.
It's much better to run somewhere than nowhere, and running nowhere is a common result of setting affinities.
Another horrible result of setting affinity on a process to a single CPU is that you confine all of that process's threads to the one CPU. Thereby killing any performance advantage that multithreading might have had.
In short, just let the Windows scheduler do its thing. The fewer options you let it have, the poorer a job it can do. | Jamie is correct BUT, there are some mainstream programs that run much better on a single thread like AutoCAD and I do assign it to a single core and it runs faster with less lags. That being said there are other components of AutoCAd such as printing that will then seem a bit slower doing this as those processes may lend themselves to multi-core functionality. I am sorry to say that the software is not well optimized for multi-core systems still!!! |
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