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https://en.wikipedia.org/wiki/Athanasius%20Kircher | Athanasius Kircher (2 May 1602 – 27 November 1680) was a German Jesuit scholar and polymath who published around 40 major works of comparative religion, geology, and medicine. Kircher has been compared to fellow Jesuit Roger Joseph Boscovich and to Leonardo da Vinci for his vast range of interests, and has been honoured with the title "Master of a Hundred Arts". He taught for more than 40 years at the Roman College, where he set up a wunderkammer. A resurgence of interest in Kircher has occurred within the scholarly community in recent decades.
Kircher claimed to have deciphered the hieroglyphic writing of the ancient Egyptian language, but most of his assumptions and translations in the field turned out to be wrong. He did, however, correctly establish the link between the ancient Egyptian and the Coptic languages, and some commentators regard him as the founder of Egyptology. Kircher was also fascinated with Sinology and wrote an encyclopedia of China, where he revealed the early presence of Nestorian Christians while also attempting to establish links with Egypt and Christianity.
Kircher's work in geology included studies of volcanoes and fossils. One of the first researchers to observe microbes through a microscope, Kircher was ahead of his time in proposing that the plague was caused by an infectious microorganism and in suggesting effective measures to prevent its spread. Kircher also displayed a keen interest in technology and mechanical inventions; inventions attributed to him include a magnetic clock, various automatons and the first megaphone. The invention of the magic lantern has been misattributed to Kircher, although he conducted a study of the principles involved in his Ars Magna Lucis et Umbrae.
A scientific star in his day, towards the end of his life he was eclipsed by the rationalism of René Descartes and others. In the late 20th century, however, the aesthetic qualities of his work again began to be appreciated. One modern scholar, Alan Cutler |
https://en.wikipedia.org/wiki/Momentus%20space | Momentus Inc, sometimes styled Momentus space, is an American spaceflight company founded by Mikhail Kokorich which plans to offer space infrastructure services in the form of on-orbit services. The company advertises three orbital tug services which are based around spacecraft electric propulsion and vary in payload mass and Delta-v. As of late 2022 the company has launched one demonstration mission, which produced mixed results.
History
Momentus space was a 2018 graduate of the Y Combinator program.
Momentus space received 8.3 million US dollars of seed funding in November 2018. The investors were Prime Movers Lab, Liquid 2 Ventures, One Way Ventures, Mountain Nazca, Y Combinator, and others.
In 2019, Momentus claimed that its Microwave Electrothermal Thruster (MET) was successfully tested in space, though the U.S. Securities and Exchange Commission accused it of misleading investors via this claim.
In 2020, Momentus was merged with a SPAC which valued it at 1.2 Billion US dollars though its valuation quickly dropped to half of this value when it began public trading.
Momentus space had its first demonstration launch of a vehicle in 2022, which achieved mixed results.
Services
Momentus space lists plans to offer "space infrastructure" services, including space transportation, on-orbit refueling, and on-orbit services of satellites. Space transportation in the form of space tugs is particularly emphasized. The website lists three models of tug with successively larger payload masses and Delta-v capabilities, in ascending order, name Vigoride, Ardoride, and Fervoride. A still larger tug, called Valoride, has since been removed from their website. These tugs are propelled by the company's Microwave Electrothermal Thruster (MET), a form of spacecraft electric propulsion in which water is ionized by microwaves and accelerated out of the spacecraft. The specific impulse of these propulsion systems is targeted to be "two or three times" that of chemical propuls |
https://en.wikipedia.org/wiki/Sortition | In governance, sortition (also known as selection by lottery, selection by lot, allotment, demarchy, stochocracy, aleatoric democracy, democratic lottery, and lottocracy) is the selection of public officials or jurors using a random representative sample. This minimizes factionalism, since those selected to serve can prioritize deliberating on the policy decisions in front of them instead of campaigning. In ancient Athenian democracy, sortition was the traditional and primary method for appointing political officials, and its use was regarded as a principal characteristic of democracy.
Today, sortition is commonly used to select prospective jurors in common-law systems. What has changed in recent years is the increased number of citizen groups with political advisory power, along with calls for making sortition more consequential than elections, as it was in Athens, Venice and Florence.
History
Ancient Athens
Athenian democracy developed in the 6th century BC out of what was then called isonomia (equality of law and political rights). Sortition was then the principal way of achieving this fairness. It was utilized to pick most of the magistrates for their governing committees, and for their juries (typically of 501 men).
Most Athenians believed sortition, not elections, to be democratic and used complex procedures with purpose-built allotment machines (kleroteria) to avoid the corrupt practices used by oligarchs to buy their way into office. According to the author Mogens Herman Hansen, the citizen's court was superior to the assembly because the allotted members swore an oath which ordinary citizens in the assembly did not, therefore the court could annul the decisions of the assembly. Most Greek writers who mention democracy (including Aristotle, Plato, Herodotus, and Pericles) emphasize the role of selection by lot, or state outright that being allotted is more democratic than elections (which were seen as oligarchic). Socrates and Isocrates however questio |
https://en.wikipedia.org/wiki/CCIR%20System%20D | CCIR System D is an analog broadcast television system used in Bulgaria, Latvia, Lithuania, Poland, Romania, Slovakia, Czech Republic, Hungary, Albania and the People's Republic of China, Mongolia, Kyrgyzstan, North Korea, Tajikistan, Turkmenistan, Uzbekistan, Armenia, Azerbaijan, Georgia, Kazakhstan, Moldova, Russia, Ukraine and Belarus paired with the PAL/SECAM colour.
Initially known as the I.B.T.O. 625-line system this was the first 625-line system, developed by Mark Iosifovich Krivosheev in 1948, and later associated with the SECAM and PAL color systems. Used on VHF only in most countries, it usually combined with System K on UHF. In China, it is used for both VHF and UHF.
Specifications
The general specifications for System D are listed below:
Frame rate: 25 Hz
Interlace: 2/1
Field rate: 50 Hz
Lines/frame: 625
Line rate: 15625 Hz
Visual bandwidth: 6 MHz
Vision modulation: Negative
Preemphasis: 50 μs
Sound modulation: FM
Sound offset: +6.5 MHz
Channel bandwidth: 8 MHz
Television channels were arranged as follows:
The original assignments of channels 25 to 57 were 2 MHz higher in frequency until c.1984. Channels 58 to 62 were deleted at this time.
See also
Broadcast television systems
Television transmitter
Transposer |
https://en.wikipedia.org/wiki/Fungal%20extracellular%20enzyme%20activity | Extracellular enzymes or exoenzymes are synthesized inside the cell and then secreted outside the cell, where their function is to break down complex macromolecules into smaller units to be taken up by the cell for growth and assimilation. These enzymes degrade complex organic matter such as cellulose and hemicellulose into simple sugars that enzyme-producing organisms use as a source of carbon, energy, and nutrients. Grouped as hydrolases, lyases, oxidoreductases and transferases, these extracellular enzymes control soil enzyme activity through efficient degradation of biopolymers.
Plant residues, animals and microorganisms enter the dead organic matter pool upon senescence and become a source of nutrients and energy for other organisms. Extracellular enzymes target macromolecules such as carbohydrates (cellulases), lignin (oxidases), organic phosphates (phosphatases), amino sugar polymers (chitinases) and proteins (proteases) and break them down into soluble sugars that are subsequently transported into cells to support heterotrophic metabolism.
Biopolymers are structurally complex and require the combined actions of a community of diverse microorganisms and their secreted exoenzymes to depolymerize the polysaccharides into easily assimilable monomers. These microbial communities are ubiquitous in nature, inhabiting both terrestrial and aquatic ecosystems. The cycling of elements from dead organic matter by heterotrophic soil microorganisms is essential for nutrient turnover and energy transfer in terrestrial ecosystems. Exoenzymes also aid digestion in the guts of ruminants, termites, humans and herbivores. By hydrolyzing plant cell wall polymers, microbes release energy that has the potential to be used by humans as biofuel. Other human uses include waste water treatment, composting and bioethanol production.
Factors influencing extracellular enzyme activity
Extracellular enzyme production supplements the direct uptake of nutrients by microorganisms and is li |
https://en.wikipedia.org/wiki/Shturmovshchina | Shturmovshchina (, last-minute rush, storming) was a common Soviet work practice of frantic and overtime work at the end of a planning period in order to fulfill the planned production target. The practice usually gave rise to products of poor quality at the end of a planning cycle.
The cycle of shturmovshchina, associated with the tradition of monthly targets (on which bonuses and managers' positions depend), is described as follows. Due to the planned economy, required materials and tools were not always available on time, and the work slowed as a result, or workers might have been reassigned to do something else, with the expectation that the job would be done when the materials arrive. However, when the end of a month neared, management was placed under pressure, substitute materials and improvised tools were used, and the workers were expected to produce the expected product in time. All this abruptly ended at the end of the month. At the beginning of the next month, the workers slacken to recover from the previous storm, thereby continuing the next cycle.
The process is known to consist of three stages:
Spiachka ('hibernation", ) – this was the first third of the planned period. Workers are not very efficient, mostly because there are no orders to do anything;
Raskachka ("buildup", ) – at this stage it is more or less known what should be done, but there is too much time ahead, and during that time the requirements may change, as well as the management;
Goriachka ("fever", ) – this is the last stage of the planned period; by the end of this stage the product is supposed to be ready, or the management may be reprimanded; workers work overtime.
See also
Charrette
Project management
Death march (project management)
Stakhanovite movement
Udarnik
Socialist emulation
State quality mark of the USSR |
https://en.wikipedia.org/wiki/Centericq |
Centericq is a text mode menu- and window-driven instant messaging interface that supports the ICQ, Yahoo!, AIM, MSN, IRC, XMPP, LiveJournal, and Gadu-Gadu protocols.
Overview
Centericq allows you to send, receive, and forward messages, URLs, SMSes (both through the ICQ server and email gateways supported by Mirabilis), contacts, and email express messages, and it has many other useful features. Known to work in Linux, FreeBSD, NetBSD, OpenBSD, Solaris, Windows and macOS/Darwin Operating Systems.
Its heyday was in the first half-decade of the 2000s, with reviews appearing in Softpedia, Czech online magazines ABC Linux and Linux.cz. It was recommended in a 2004 OSNews article on console applications, and in a similar article in the Russian magazine Computerra. Two tutorial articles appeared in the German magazine LinuxUser in 2001 and 2004; the latter article appeared in the English version of Linux Magazine. It was included in a 2002 round-up of ICQ clients in the Russian XAKEP magazine, and in a 2005 round-up review of IRC Clients in Free Software Magazine. The FSM reviewer noted Centericq for its windows-like interface built on top of the usual curses library, which provides much information, but can look cluttered on smaller terminal windows, including the standard 80 by 25 terminal. It found that IRC support was "excellent" due to support for multiple servers and channels and the ease of switching between them in the “windowed” interface. In September 2002, Steven J. Vaughan-Nichols found it "the greatest of all console IM clients" due to its "excellent interface and a huge number of features and configuration options" in a category review on Freshmeat. In 2005 it was reviewed in The Unofficial Apple Weblog; despite support for .mac accounts, the reviewer noted "annoying key combos" required to access the menus, because on Mac OS X the usual function key assignments of Centericq could not be used. Though he could not access the MSN network, he concluded: "A |
https://en.wikipedia.org/wiki/Overcategory | In mathematics, specifically category theory, an overcategory (and undercategory) is a distinguished class of categories used in multiple contexts, such as with covering spaces (espace etale). They were introduced as a mechanism for keeping track of data surrounding a fixed object in some category . There is a dual notion of undercategory, which is defined similarly.
Definition
Let be a category and a fixed object of pg 59. The overcategory (also called a slice category) is an associated category whose objects are pairs where is a morphism in . Then, a morphism between objects is given by a morphism in the category such that the following diagram commutesThere is a dual notion called the undercategory (also called a coslice category) whose objects are pairs where is a morphism in . Then, morphisms in are given by morphisms in such that the following diagram commutesThese two notions have generalizations in 2-category theory and higher category theorypg 43, with definitions either analogous or essentially the same.
Properties
Many categorical properties of are inherited by the associated over and undercategories for an object . For example, if has finite products and coproducts, it is immediate the categories and have these properties since the product and coproduct can be constructed in , and through universal properties, there exists a unique morphism either to or from . In addition, this applies to limits and colimits as well.
Examples
Overcategories on a site
Recall that a site is a categorical generalization of a topological space first introduced by Grothendieck. One of the canonical examples comes directly from topology, where the category whose objects are open subsets of some topological space , and the morphisms are given by inclusion maps. Then, for a fixed open subset , the overcategory is canonically equivalent to the category for the induced topology on . This is because every object in is an open subset contained in .
|
https://en.wikipedia.org/wiki/Aging%20and%20Mental%20Health | Aging & Mental Health is a peer-reviewed monthly scientific journal published by Routledge covering research on the relationship between the aging process and mental health. The editors-in-chief are Martin Orrell, Rebecca Allen, and Terry Lum.
Abstracting and indexing
The journal is abstracted and indexed in PubMed and Web of Science. According to the Journal Citation Reports, the journal has a 2020 impact factor of 3.658. |
https://en.wikipedia.org/wiki/The%20Weather%20Man | The Weather Man is a 2005 American dark comedy-drama film directed by Gore Verbinski, written by Steve Conrad, and starring Nicolas Cage in the lead role and Michael Caine and Hope Davis in supporting roles. It tells the story of a weatherman in the midst of a mid-life crisis.
The film was released on October 28, 2005, and grossed $19 million worldwide. It received mixed reviews upon release.
Plot
A successful weatherman at a Chicago news program, David Spritz (Nicolas Cage) is well paid but garners little respect from people in the area who throw fast food at him, David suspects, because they're resentful of how easy his high-paying job is. Dave also feels overshadowed by his father, Pulitzer Prize-winning author Robert Spritzel (Michael Caine), who is disappointed in Dave's apparent inability to grow up and deal with his two children. The situation worsens when Robert is diagnosed with lymphoma and given only a few months to live. As he becomes more and more depressed, Dave takes up archery, finding the activity a way to build his focus and calm his nerves.
David later remembers a conversation between himself and his father, where his father explains to him that "the harder thing to do and the right thing to do are often the same thing" and that "nothing that has meaning is easy". David appreciates this advice but struggles to implement it.
To prove himself to his father and possibly reconcile with Noreen (Hope Davis), his estranged wife, Dave pursues a weatherman position with a national talk show called Hello America. The job would nearly quadruple his salary, but means relocating to New York City. When Hello America invites him to New York, he takes his daughter, Shelly (Gemmenne de la Peña), with him and bonds with her by helping her shop for a more suitable wardrobe. While away, Dave learns that his son Mike (Nicholas Hoult) attacked his counselor, Don Bowden (Gil Bellows), claiming that the man wanted to perform oral sex on him. Despite this stress an |
https://en.wikipedia.org/wiki/Silk%20Mark | Silk Mark is a certification mark in India for silk textiles. The mark certifies that the piece of textile which bears the mark is made of pure natural silk. The certification is managed by the 'Silk Mark Organisation of India', a society set up by the state-controlled Central Silk Board of India. Even though promoted by the government of India, the mark is only advisory in nature and is not legally endorsed. The certification scheme was founded by the Central Silk Board in 2004. In the original format, the mark included a silk mark logo woven on a hang-on tag on which a unique numbered hologram would be affixed. But the hang-on tag tended to be faked (reused) hence, a new method with the mark woven onto the textile itself has been proposed.
The certification process assures the consumer a facility for free testing of the marked product in Silk Mark Chapters (accredited labs) in case of doubt.
See also
Certification marks in India
Geographical Indications marks |
https://en.wikipedia.org/wiki/Bulk%20soil | Bulk soil is soil outside the rhizosphere that is not penetrated by plant roots. The bulk soil is like an ecosystem, it is made up of many things such as: nutrients, ions, soil particles, and root exudates. There are many different interactions that occur between all the members of the bulk soil. Natural organic compounds are much lower in bulk soil than in the rhizosphere. Furthermore, bulk soil inhabitants are generally smaller than identical species in the rhizosphere. The main two aspects of bulk soil are its chemistry and microbial community composition.
Chemistry of bulk soil
Soil is made up of layers called soil horizons, these make up a vertical soil profile. There are five master horizons O, A, E, B, and C. The O horizon contains organic matter, A is considered the topsoil, E is present or absent depending on the type of soil and conditions, B is the subsoil, and C is unconsolidated rock. There are many chemical interactions and properties that are in all the soil. Chemical properties of the bulk soil are organic matter, carbon, nutrient content, cation-exchange capacity (CEC), free ions (cations or anions), pH, and base saturation and organisms. These can impact many chemical processes such as nutrient cycling, soil formation, biological activity, and erosion.
Microbial communities
Soil is composed of a diverse community of microbes such as: fungi, bacteria, archaea, viruses and microfauna. There are microbes in the bulk soil and the rhizosphere, the variation of microbes increases in the bulk soil and the abundance of microbes increases in the rhizosphere. Some microbes can form symbioses with plants that are beneficial or pathogenic. All these microbes have a special role in many soil processes such as soil formation, organic matter decomposition, nutrient cycling. For example, there are microbes in the rhizosphere (on the plant) that can break down nitrogen, and microbes out in the bulk can break down nitrogen as well. Both have different factors |
https://en.wikipedia.org/wiki/Stannide | A stannide can refer to an intermetallic compound containing tin combined with one or more other metals; an anion consisting solely of tin atoms or a compound containing such an anion, or, in the field of organometallic chemistry an ionic compound containing an organotin anion (e.g.see an alternative name for such a compound is stannanide.)
Binary alkali and alkaline earth stannides
When tin is combined with an alkali or alkaline earth metal some of the compounds formed have ionic structures containing monatomic or polyatomic tin anions (Zintl ions), such as Sn4− in Mg2Sn or in K4Sn9.
Even with these metals not all of the compounds formed can be considered to be ionic with localised bonding, for example Sr3Sn5, a metallic compound, contains {Sn5} square pyramidal units.
Ternary alkali and alkaline earth stannides
Ternary (where there is an alkali or alkaline earth metal, a transition metal as well as tin e.g. LiRh3Sn5 and MgRuSn4) have been investigated.
Other metal stannides
Binary (involving one other metal) and ternary (involving two other metals) intermetallic stannides have been investigated. Niobium stannide, Nb3Sn is perhaps the best known superconducting tin intermetallics. This is more commonly called "niobium-tin".
Stannide ions,
Some examples of stannide Zintl ions are listed below. Some of them contain 2-centre 2-electron bonds (2c-2e), others are "electron deficient" and bonding sometimes can be described using polyhedral skeletal electron pair theory (Wade's rules) where the number of valence electrons contributed by each tin atom is considered to be 2 (the s electrons do not contribute). There are some examples of silicide and plumbide ions with similar structures, for example tetrahedral , the chain anion (Si2−)n, and .
Sn4− found for example in Mg2Sn.
, tetrahedral with 2c-2e bonds e.g. in CsSn.
, tetrahedral closo-cluster with 10 electrons (2n + 2).
(Sn2−)n zig-zag chain polymeric anion with 2c-2e bonds found for example in BaSn.
closo- |
https://en.wikipedia.org/wiki/Data%20Radio%20Channel | Data Radio Channel (DARC) is a high-rate (16 kbit/s) standard for encoding data in a subcarrier over FM radio broadcasts. It uses a frequency of 76kHz, the fourth harmonic of the FM radio pilot tone.
DARC was approved as the All-European standard ETS 300 751 in 1997.
Applications
DARC is well-suited to distributing traffic information because of its higher speed. In Japan, the VICS (Vehicle Information and Communication System) service has operated since 1996 in the Tokyo, Nagoya and Osaka metropolitan areas. In France, DARC has been tested for traffic message channel services.
In the United States, it was used to deliver stock market quotations by Digital DJ beginning in 1998.
In Munich, DARC is used to transmit public transport data to battery-powered signs in bus and tram stations.
Similar technologies
Other data broadcasting technologies include RDS and Microsoft's DirectBand. |
https://en.wikipedia.org/wiki/Imagix%204D | Imagix 4D is a source code analysis tool from Imagix Corporation, used primarily for understanding, documenting, and evolving existing C, C++ and Java software.
Applied technologies include full semantic source analysis. Software visualization supports program comprehension. Static data flow analysis-based verifications detect problems in variable usage, task interactions and concurrency. Software metrics measure design quality and identify potential testing and maintenance issues.
See also
Rational Rose
Rigi
Software visualization
List of tools for static code analysis
Sourcetrail |
https://en.wikipedia.org/wiki/Allan%E2%80%93Herndon%E2%80%93Dudley%20syndrome | Allan–Herndon–Dudley syndrome is a rare X-linked inherited disorder of brain development that causes both moderate to severe intellectual disability and problems with speech and movement.
Allan–Herndon–Dudley syndrome, which is named eponymously for William Allan, Florence C. Dudley, and C. Nash Herndon, results from a mutation of the thyroid hormone transporter MCT8 (also referred to as SLC16A2). Consequently, thyroid hormones are unable to enter the nervous system, which depends on thyroid signaling for proper function and development.
Signs and symptoms
It is estimated that 80–99% of people with Allan–Herndon–Dudley syndrome will have biparietal narrowing (narrowing of skull), ataxia, abnormalities of the neck, and both absent speech development and aphasia. Weak muscle tone (hypotonia) and underdevelopment of many muscles (muscle hypoplasia) are common in children with Allan–Herndon–Dudley syndrome. Development of joint deformities called contractures, which restrict the movement of certain joints, are common as people age. Mobility is further limited by abnormal muscle stiffness (spasticity), muscle weakness, and involuntary movements of the arms and legs. Many people with Allan–Herndon–Dudley syndrome are unable to walk independently and become wheelchair-reliant by adulthood.
Endocrine phenotype
The typical hormonal signature of AHDS is marked by low free T4 and normal or elevated free T3 concentration, which translates to increased calculated deiodinase activity (SPINA-GD).
Genetics
This condition is inherited in an X-linked recessive pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a mutation must be present in both copies of the gene to cause the disorder. Males are affected by X-linke |
https://en.wikipedia.org/wiki/Shovelware | Shovelware is a term for individual video games or software bundles known more for the quantity of what is included than for the quality or usefulness.
The metaphor implies that the creators showed little care for the quality of the original software, as if the new compilation or version had been created by indiscriminately adding titles "by the shovel" in the same way someone would shovel bulk material into a pile. The term "shovelware" is coined by semantic analogy to phrases like shareware and freeware, which describe methods of software distribution. It first appeared in the early 1990s when large amounts of shareware demo programs were copied onto CD-ROMs and advertised in magazines or sold at computer flea markets.
Shovelware CD-ROMs
Computer Gaming World wrote in 1990 that for "those who do not wish to wait" for software that used the new CD-ROM format, The Software Toolworks and Access Software planned to release "game packs of several classic titles". By 1993 the magazine referred to software repackaged on CD-ROM as "shovelware", describing one collection from Access as having a "rather dusty menu" and another from The Software Toolworks ("the reigning king of software repackaging efforts") as including games that were "mostly mediocre even in their prime"; the one exception, Chessmaster 2000, used "stunning CGA graphics". In 1994 the magazine described shovelware as "old and/or weak programs shoveled onto a CD to turn a quick buck".
The capacity of a CD-ROM was 450–700 times that of the floppy disk, and 6–16 times larger than the hard disks with which personal computers were commonly outfitted in 1990. This outsized capacity meant that very few users would install the discs' entire contents, encouraging producers to fill them by including as much existing content as possible, often without regard to the quality of the material. Advertising the number of titles on the disc often took precedence over the quality of the content. Software reviewers, disple |
https://en.wikipedia.org/wiki/Control%20line | Control line (also called U-Control) is a simple and light way of controlling a flying model aircraft. The aircraft is connected to the operator by a pair of lines, attached to a handle, that work the elevator of the model. This allows the model to be controlled in the pitch axis. It is constrained to fly on the surface of a hemisphere by the control lines.
The control lines are usually either stranded stainless steel cable or solid metal wires of anywhere from to . Sewing thread or braided fishing line may be used instead of wires, but air resistance is greater. A third line is sometimes used to control the engine throttle, and more lines may be added to control other functions. Electrical signals sent over the wires are sometimes used in scale models to control functions such as retracting undercarriage and flaps.
There is also a control system that uses a single solid wire, this is called Monoline. When the pilot twists the wire around its axis, a spiral inside the airplane spins to move the elevator. While it can be used with some success on any type of model, it is best for speed models where the reduced aerodynamic drag of the single line is a significant advantage. The control provided is not as precise as the two-line control system.
Almost all control-line models are powered with conventional model aircraft engines of various types. It is possible to fly control-line models that do not use on-board propulsion, in a mode called "whip-powered", where the pilot "leading" the model, whose lines are attached to a fishing or similar pole, supplying the necessary energy to keep the airplane aloft, in a fashion similar to kite-flying.
History
Early versions merely constrained the model to fly in a circle but offered no control. This is known as round-the-pole flying. The origins of control-line flight are obscure, but the first person to use a recognizable system that manipulated the control surfaces on the model is generally considered to be Oba St. Clair, in |
https://en.wikipedia.org/wiki/List%20of%20Rhodesian%20flags | This is a list of flags used in Southern Rhodesia between 1890–1964 and 1979–1980 and Rhodesia between 1964 and 1979. The evolution of Southern Rhodesia from a British South African Company concern, to a British Colony, then to a member of a Federal Government, then to a self-declared state is evident by the different flags used.
For flags after these dates see Flags of Zimbabwe.
National flags
Vice-regal and presidential
Military flags
Political flags
Town flags |
https://en.wikipedia.org/wiki/International%20Programme%20on%20the%20State%20of%20the%20Ocean | The International Programme on the State of the Ocean (IPSO) focuses on the many factors that threaten the health of Earth's oceans. The organization is managed as a not for profit company registered in the United Kingdom. It is hosted by the Zoological Society of London. Dr. Alex Rogers is the Scientific Director of IPSO and Professor of Conservation Biology at the Department of Zoology, University of Oxford.
Areas of research
Effects of climate change on oceans
Overfishing
Ocean acidification
Habitat destruction of marine lifeforms
Fisheries and climate change
Detrimental resource extractions
Marine pollution
Introduced species in marine environments |
https://en.wikipedia.org/wiki/Observer%20bias | Observer bias is one of the types of detection bias and is defined as any kind of systematic divergence from accurate facts during observation and the recording of data and information in studies. The definition can be further expanded upon to include the systematic difference between what is observed due to variation in observers, and what the true value is.
Observer bias is the tendency of observers to not see what is there, but instead to see what they expect or want to see. This is a common occurrence in the everyday lives of many and is a significant problem that is sometimes encountered in scientific research and studies. Observation is critical to scientific research and activity, and as such, observer bias may be as well. When such biases exist, scientific studies can result in an over- or underestimation of what is true and accurate, which compromises the validity of the findings and results of the study, even if all other designs and procedures in the study were appropriate.
Observational data forms the foundation of a significant body of knowledge. Observation is a method of data collection and falls into the category of qualitative research techniques. There are a number of benefits of observation, including its simplicity as a data collection method and its usefulness for hypotheses. Simultaneously, there are many limitations and disadvantages in the observation process, including the potential lack of reliability, poor validity, and faulty perception. Participants' observations are widely used in sociological and anthropological studies, while systematic observation is used where researchers need to collect data without participants direct interactions. The most common observation method is naturalistic observation, where subjects are observed in their natural environments with the goal to assess the behaviour in an intervention free and natural setting.
Observer bias is especially probable when the investigator or researcher has vested interests in |
https://en.wikipedia.org/wiki/Gable%20stone | Gable stones (Dutch gevelstenen) are carved and often colourfully painted stone tablets, which are set into the walls of buildings, usually at about 4 metres from the ground. They serve both to identify and embellish the building. They are also called "stone tablets" by the Rijksmuseum, which sometimes appends "from a facade". A "wall stone" is another suggested translation from the Dutch term.
The content of gable stones may explain something about the house's owner and are a feature of the urban fabric of Amsterdam. Some 2,500 of these stones can still be found in the Netherlands, of which around 850 are in Amsterdam and 250 in Maastricht, while others are also found in cities such as Brussels, Liège, Lille, Oslo, Bergen, Munich, Copenhagen, Bucharest, Zurich, Stockholm and Warsaw.
History
Gable stones came into use in the 16th century, in the days before house numbers, taking over from hanging signs as a way of simultaneously and memorably identifying and adorning a house.
The tradition is alive and has moved with the times – new stones are still commissioned, and for instance the Rabobank at Frederiksplein 54 in Amsterdam wistfully commemorates the introduction of the euro with a stone entitled De eerste en de laatste gulden (The first and the last guilder), created by Zutphen sculptor Hans 't Mannetje.
In Amsterdam, many gable stones have been conserved by the Vereniging Vrienden van Amsterdamse Gevelstenen (VVAG) or Friends of Amsterdam Gable Stones.
Features
They normally combine a picture with an inscription, or sometimes just a date. Some illustrate the name or profession of the owner, for instance a quill pen as a badge for an author, or a ship for a sailor. Some are named after notable people (The King of Bohemia) or faraway trading destinations (Königsberg). Some stones act as talismans, quoting from holy scripture. A pious motto repeatedly found on Dutch gable stones is Nooit Volmaakt (Never Perfect), a testimony to the householder's belief that on |
https://en.wikipedia.org/wiki/Bianconi%E2%80%93Barab%C3%A1si%20model | The Bianconi–Barabási model is a model in network science that explains the growth of complex evolving networks. This model can explain that nodes with different characteristics acquire links at different rates. It predicts that a node's growth depends on its fitness and can calculate the degree distribution. The Bianconi–Barabási model is named after its inventors Ginestra Bianconi and Albert-László Barabási. This model is a variant of the Barabási–Albert model. The model can be mapped to a Bose gas and this mapping can predict a topological phase transition between a "rich-get-richer" phase and a "winner-takes-all" phase.
Concepts
The Barabási–Albert (BA) model uses two concepts: growth and preferential attachment. Here, growth indicates the increase in the number of nodes in the network with time, and preferential attachment means that more connected nodes receive more links. The Bianconi–Barabási model, on top of these two concepts, uses another new concept called the fitness. This model makes use of an analogy with evolutionary models. It assigns an intrinsic fitness value to each node, which embodies all the properties other than the degree. The higher the fitness, the higher the probability of attracting new edges. Fitness can be defined as the ability to attract new links – "a quantitative measure of a node's ability to stay in front of the competition".
While the Barabási–Albert (BA) model explains the "first mover advantage" phenomenon, the Bianconi–Barabási model explains how latecomers also can win. In a network where fitness is an attribute, a node with higher fitness will acquire links at a higher rate than less fit nodes. This model explains that age is not the best predictor of a node's success, rather latecomers also have the chance to attract links to become a hub.
The Bianconi–Barabási model can reproduce the degree correlations of the Internet Autonomous Systems. This model can also show condensation phase transitions in the evolution of com |
https://en.wikipedia.org/wiki/Paessler%20PRTG | PRTG (Paessler Router Traffic Grapher until version 7) is an agentless network monitoring software from Paessler AG. Several software versions are combined under the umbrella term Paessler PRTG. It is designed to monitor and classify system conditions like bandwidth usage or uptime and collect statistics from miscellaneous hosts such as switches, routers, servers, and other devices and applications.
The first version of PRTG was released on 29 May 2003 by the German company Paessler GmbH (now: Paessler AG), which was founded by Dirk Paessler in 2001.
Products of the Paessler PRTG family
The monitoring software Paessler PRTG is available in three versions. In addition to the classic standalone solution PRTG Network Monitor, Paessler sells PRTG Enterprise Monitor for large and distributed networks and PRTG Hosted Monitor as a SaaS-version.
PRTG Network Monitor
PRTG Network Monitor is the classic on-premises monitoring solution, which is hosted on a server in the user's network. For the installation of the core server, a computer with the Windows Server operating system is required.
PRTG Enterprise Monitor
Since 2020, Paessler has offered PRTG Enterprise Monitor, a specialized monitoring solution for large IT environments. In addition to a particularly high performance for distributed locations, PRTG Enterprise Monitor also includes the ITOps Board, which provides a centralized service-oriented overview. It can be used to map business processes, consolidate dashboards from multiple servers, and monitor SLA performance and availability, among other features.
PRTG Hosted Monitor
In 2017, a cloud-hosted version of PRTG was released. PRTG Hosted Monitor offers largely the same range of functions as the standard tool. The license is billed monthly and is based solely on the number of sensors. In contrast to PRTG Network Monitor and PRTG Enterprise Monitor, PRTG Hosted Monitor can also be used in networks without a Windows server, since it is hosted in the cloud and |
https://en.wikipedia.org/wiki/Preformationism | In the history of biology, preformationism (or preformism) is a formerly popular theory that organisms develop from miniature versions of themselves. Instead of assembly from parts, preformationists believed that the form of living things exist, in real terms, prior to their development. Preformationists suggested that all organisms were created at the same time, and that succeeding generations grow from homunculi, or animalcules, that have existed since the beginning of creation, which is typically defined by religious beliefs.
Epigenesis (or neoformism), then, in this context, is the denial of preformationism: the idea that, in some sense, the form of living things comes into existence. As opposed to "strict" preformationism, it is the notion that "each embryo or organism is gradually produced from an undifferentiated mass by a series of steps and stages during which new parts are added" (Magner 2002, p. 154). This word is still used in a more modern sense, to refer to those aspects of the generation of form during ontogeny that are not strictly genetic, or, in other words, epigenetic.
Apart from those distinctions (preformationism-epigenesis and genetic-epigenetic), the terms preformistic development, epigenetic development and somatic embryogenesis are also used in another context, in relation to the differentiation of a distinct germ cell line. In preformistic development, the germ line is present since early development. In epigenetic development, the germ line is present, but it appears late. In somatic embryogenesis, a distinct germ line is lacking. Some authors call Weismannist development (either preformistic or epigenetic) that in which there is a distinct germ line.
The historical ideas of preformationism and epigenesis, and the rivalry between them, are obviated by the contemporary understanding of the genetic code and its molecular basis together with developmental biology and epigenetics.
Philosophical development
Pythagoras is one of the earliest |
https://en.wikipedia.org/wiki/Euclid%27s%20orchard | In mathematics, informally speaking, Euclid's orchard is an array of one-dimensional "trees" of unit height planted at the lattice points in one quadrant of a square lattice. More formally, Euclid's orchard is the set of line segments from to , where and are positive integers.
The trees visible from the origin are those at lattice points , where and are coprime, i.e., where the fraction is in reduced form. The name Euclid's orchard is derived from the Euclidean algorithm.
If the orchard is projected relative to the origin onto the plane (or, equivalently, drawn in perspective from a viewpoint at the origin) the tops of the trees form a graph of Thomae's function. The point projects to
The solution to the Basel problem can be used to show that the proportion of points in the grid that have trees on them is approximately and that the error of this approximation goes to zero in the limit as goes to infinity.
See also
Opaque forest problem |
https://en.wikipedia.org/wiki/Vacuum%20filler | A vacuum filler is a machine used for filling pasty products. The pasty products are moved with the aid of a vane cell feed system under a vacuum.
Objective
Levelling the weight of pre-packaged goods in the food sector, especially those involving viscous or pasty products, places extremely high demands on the reproducible accuracy of filling and portioning systems. In order to achieve this, technical and technological issues as well as product-specific characteristics have to be taken into account. In addition to the aforementioned factors, the requirements on the quality of an end product is a key issue when selecting or implementing a technical process solution. The development of vacuum filling machines has made it possible to fulfill both the technical and the quality-related requirements.
In the food sector, moving or transporting fluids is achieved with the aid of pump technology. Colloquially, this is known as filling or portioning. Various different types of pumps are used, depending on the type of filling products to be moved. Vacuum fillers with vane cell feed systems and vacuum feeding are commonly used for viscous products. The products are transported with the aid of a hopper with a feeding device, a vane cell feed system under a vacuum and appropriate volume expulsion in the pump housing. This is basically a volumetric feed principle, which means that a certain weight is defined via a volume. In addition to the vane cell feed systems, also known as rotary vane pumps, there are also screw feed systems with feed augers, toothed wheel feed systems and evacuated lifting cylinders. With all these systems, transportation is achieved via volume expulsion under a vacuum.
Vacuum fillers are traditionally used in the meat processing industry as well as in other food sectors. They can also be found in some non-food sectors. Generally speaking, vacuum fillers can be used for filling pasty and compressible products.
History
The first vacuum filler was develop |
https://en.wikipedia.org/wiki/Sickness%20behavior | Sickness behavior is a coordinated set of adaptive behavioral changes that develop in ill individuals during the course of an infection.
They usually, but not always, accompany fever and aid survival.
Such illness responses include lethargy, depression, anxiety, malaise, loss of appetite, sleepiness, hyperalgesia, reduction in grooming and failure to concentrate.
Sickness behavior is a motivational state that reorganizes the organism's priorities to cope with infectious pathogens.
It has been suggested as relevant to understanding depression, and some aspects of the suffering that occurs in cancer.
History
Sick animals have long been recognized by farmers as having different behavior. Initially it was thought that this was due to physical weakness that resulted from diverting energy to the body processes needed to fight infection. However, in the 1960s, it was shown that animals produced a blood-carried factor X that acted upon the brain to cause sickness behavior. In 1987, Benjamin L. Hart brought together a variety of research findings that argued for them being survival adaptations that if prevented would disadvantage an animal's ability to fight infection. In the 1980s, the blood-borne factor was shown to be proinflammatory cytokines produced by activated leukocytes in the immune system in response to lipopolysaccharides (a cell wall component of Gram-negative bacteria). These cytokines acted by various humoral and nerve routes upon the hypothalamus and other areas of the brain. Further research showed that the brain can also learn to control the various components of sickness behavior independently of immune activation..
In 2015, Shakhar and Shakhar suggested instead that sickness behavior developed primarily because it protected the kin of infected animals from transmissible diseases. According to this theory, termed the Eyam hypothesis, after the English Parish of Eyam, sickness behavior protects the social group of infected individuals by limiting their di |
https://en.wikipedia.org/wiki/Suspensor | Suspensors are anatomical structures found in certain fungi and plants.
Fungi
In fungi, suspensors are filamentous structural formations having the function of holding a zygospore between two strains of hyphae.
Plants
In plants, suspensors are found in zygotes in angiosperms, connecting the endosperm to an embryo. Usually in dicots the suspensor cells divide transversally a few times to form a filamentous suspensor of 6-10 cells. The suspensor helps in pushing the embryo into the endosperm. The first cell of the suspensor towards the micropylar end becomes swollen and functions as a haustorium. The haustorium has wall ingrowths similar to those of a transfer cell. The last of the suspensors at the end of the embryo is known as hypophysis. Hypophysis later gives rise to the radicle and root cap. During embryo development in angiosperm seeds, normal development involves asymmetrical division of the unicellular embryo, inducing polarity. The smaller terminal cell divides to become the proembryo while the larger basal cell divides laterally to form the suspensor. The suspensor is analogous to a placental mammalian's umbilical cord. |
https://en.wikipedia.org/wiki/EX%C3%8DN%20Castles | EXÍN Castillos (or EXIN Castles) is a construction toy. First introduced by the Exin Lines Brothers in 1968 in Barcelona, Spain, this plastic block toy was designed for the construction of castle-like-buildings. The company has most recently produced Castle lines toys for the Shrek movie franchise and others.
The EXIN Castillos blocks are of a peg-and-socket design similar to Lego or TENTE, though with larger pegs, and the most common size being a 1x2 design (whereas 2x4 is the most common Lego size). The blocks are usually a mottled light tan color, intended to resemble stone, although a few sets were produced using pale blue blocks instead, for a "fantasy" theme.
Beyond the standard blocks, additional specialized pieces in EXIN sets include arched top pieces for windows and doors, smooth caps to create battlements, single-piece tower tops and turret roofs to attach to those, wall-mounted torches and braziers, etc.
The existence of these specialized pieces made the EXIN blocks especially suitable for their particular role of building castles in the early 1970s, before Lego had anything similar. The later introduction of more specialized Lego sets in the late 1980s and onwards, which were equally well suited for such a task, yet still interoperable with generic Lego, gave increased competition to EXIN. |
https://en.wikipedia.org/wiki/University%20of%20Michigan%20Biological%20Station | The University of Michigan Biological Station (UMBS) is a research and teaching facility operated by the University of Michigan. It is located on the south shore of Douglas Lake in Cheboygan County, Michigan. The station consists of 10,000 acres (40 km2) of land near Pellston, Michigan in the northern Lower Peninsula of Michigan and 3,200 acres (13 km2) on Sugar Island in the St. Mary's River near Sault Ste. Marie, in the Upper Peninsula. It is one of only 28 Biosphere Reserves in the United States.
Overview
Founded in 1909, it has grown to include approximately 150 buildings, including classrooms, student cabins, dormitories, a dining hall, and research facilities. Undergraduate and graduate courses are available in the spring and summer terms. It has a full-time staff of 15.
In the 2000s, UMBS is increasingly focusing on the measurement of climate change. Its field researchers are gauging the impact of global warming and increased levels of atmospheric carbon dioxide on the ecosystem of the upper Great Lakes region, and are using field data to improve the computer models used to forecast further change. Several archaeological digs have been conducted at the station as well.
UMBS field researchers sometimes call the station "bug camp" amongst themselves. This is believed to be due to the number of mosquitoes and other insects present. It is also known as "The Bio-Station".
The UMBS is also home to Michigan's most endangered species and one of the most endangered species in the world: the Hungerford's Crawling Water Beetle. The species lives in only five locations in the world, two of which are in Emmet County. One of these, a two and a half mile stretch downstream from the Douglas Road crossing of the East Branch of the Maple River supports the only stable population of the Hungerford's Crawling Water Beetle, with roughly 1000 specimens. This area, though technically not part of the UMBS is largely within and along the boundary of the University of Michigan |
https://en.wikipedia.org/wiki/Neutron%20flux | The neutron flux, φ, is a scalar quantity used in nuclear physics and nuclear reactor physics. It is the total distance travelled by all free neutrons per unit time and volume. Equivalently, it can be defined as the number of neutrons travelling through a small sphere of radius in a time interval, divided by a maximal cross section of the sphere (the great disk area, ) and by the duration of the time interval. The dimension of neutron flux is and the usual unit is cm−2s−1 (reciprocal square centimetre times reciprocal second).
The neutron fluence is defined as the neutron flux integrated over a certain time period. So its dimension is and its usual unit is cm−2 (reciprocal square centimetre). An older term used instead of cm−2 was "n.v.t." (neutrons, velocity, time).
Natural neutron flux
Neutron flux in asymptotic giant branch stars and in supernovae is responsible for most of the natural nucleosynthesis producing elements heavier than iron. In stars there is a relatively low neutron flux on the order of 105 to 1011 cm−2 s−1, resulting in nucleosynthesis by the s-process (slow neutron-capture process). By contrast, after a core-collapse supernova, there is an extremely high neutron flux, on the order of 1032 cm−2 s−1, resulting in nucleosynthesis by the r-process (rapid neutron-capture process).
Earth atmospheric neutron flux, apparently from thunderstorms, can reach levels of 3·10−2 to 9·10+1 cm−2 s−1. However, recent results (considered invalid by the original investigators) obtained with unshielded scintillation neutron detectors show a decrease in the neutron flux during thunderstorms. Recent research appears to support lightning generating 1013–1015 neutrons per discharge via photonuclear processes.
Artificial neutron flux
Artificial neutron flux refers to neutron flux which is man-made, either as byproducts from weapons or nuclear energy production or for a specific application such as from a research reactor or by spallation. A flow of neutrons is oft |
https://en.wikipedia.org/wiki/Directory%20harvest%20attack | A directory harvest attack (DHA) is a technique used by spammers in an attempt to find valid/existent e-mail addresses at a domain by using brute force. The attack is usually carried out by way of a standard dictionary attack, where valid e-mail addresses are found by brute force guessing valid e-mail addresses at a domain using different permutations of common usernames. These attacks are more effective for finding e-mail addresses of companies since they are likely to have a standard format for official e-mail aliases (i.e. jdoe@example.domain, johnd@example.domain, or johndoe@example.domain).
There are two main techniques for generating the addresses that a DHA targets. In the first, the spammer creates a list of all possible combinations of letters and numbers up to a maximum length and then appends the domain name. This would be described as a standard brute force attack. This technique would be impractical for usernames longer than 5-7 characters. For example, one would have to try 368 (nearly 3 trillion) e-mail addresses to exhaust all 8-character sequences.
The other, more targeted technique, is to create a list that combines common first name and surnames and initials (as in the example above). This would be considered a standard dictionary attack when guessing usernames for e-mail addresses. The success of a directory harvest attack relies on the recipient e-mail server rejecting e-mail sent to invalid recipient e-mail addresses during the Simple Mail Transfer Protocol (SMTP) session. Any addresses to which email is accepted are considered valid and are added to the spammer's list (which is commonly sold between spammers). Although the attack could also rely on Delivery Status Notifications (DSNs) to be sent to the sender address to notify of delivery failures, directory harvest attacks likely don't use a valid sender e-mail address.
The actual e-mail message generated to the recipient addresses will usually be a short random phrase such as "hello", s |
https://en.wikipedia.org/wiki/Charles%20Darwin%20Research%20Station | Charles Darwin Research Station (CDRS) (, ECCD) is a biological research station in Puerto Ayora, Santa Cruz Island, Galápagos, Ecuador. The station is operated by the Charles Darwin Foundation which was founded in 1959 under the auspices of UNESCO and the World Conservation Union. The research station serves as the headquarters for the Foundation, and is used to conduct scientific research and promote environmental education. It is located on the shore of Academy Bay in the village of Puerto Ayora on Santa Cruz Island in the Galapagos Islands, with satellite offices on Isabela and San Cristóbal islands.
Field station
The Charles Darwin Research Station (CDRS) (, ECCD) is a biological research station operated by the Charles Darwin Foundation. It is located on the shore of Academy Bay in the village of Puerto Ayora on Santa Cruz Island in the Galapagos Islands, with satellite offices on Isabela and San Cristóbal islands. In Puerto Ayora, Santa Cruz Island, Ecuadorian and foreign scientists work on research and projects for conservation of the Galápagos terrestrial and marine ecosystems. The Research Station, established in 1959 and dedicated in 1964, has a natural history interpretation center and also carries out educational projects in support of conservation of the Galápagos Islands, and in support of external researchers visiting the islands to conduct field work.
Objectives and work
The objectives of the CDRS is to conduct scientific research and environmental education for conservation. The Station has a team of over a hundred scientists, educators, volunteers, research students, and support staff from all over the world.
Scientific research and monitoring projects are conducted at the CDRS in conjunction and cooperation with its chief partner, the Galápagos National Park Directorate (GNPD), which functions as the principal government authority in charge of conservation and natural resource issues in the Galapagos.
The work of the CDRS has as its main |
https://en.wikipedia.org/wiki/Calculator%20%28Apple%29 | Calculator is a basic calculator application made by Apple Inc. and bundled with its macOS, iOS, and watchOS operating systems. It has three modes: basic, scientific, and programmer. The basic mode includes a number pad, buttons for adding, subtracting, multiplying, and dividing, as well as memory keys. Scientific mode supports exponents and trigonometric functions. The macOS version of Calculator guys apple is the worst also has a programmer mode that gives the user access to more options related to computer programming.
The Calculator program has a long associated history with the beginning of the Macintosh platform, where a simple four-function calculator program was a standard desk accessory from the earliest system versions. Though no higher math capability was included, third-party developers provided upgrades, and Apple released the Graphing Calculator application with the first PowerPC release (7.1.2) of the Mac OS, and it was a standard component through Mac OS 9. Apple also ships a different application with macOS called Grapher for this purpose.
A calculator function has been included with iOS since its launch on iPhone and iPod Touch. However, iPads have never had a first party calculator application. A native calculator function was added to the Apple Watch with watchOS 6, which included a dedicated button for calculating tips.
Features
Calculator has Reverse Polish notation support, and can also speak the buttons pressed and result returned.
The calculator also includes some basic conversion functions to convert between units in the following categories:
Area
Currency (exchange rates may be updated over the Internet)
Energy or Work
Temperature
Length
Speed
Pressure
Weight/Mass
Power
Volume
Since the release of Mac OS X Leopard, simple arithmetic functions can be calculated from the Spotlight feature. They include the standard addition, subtraction, multiplication, and division operations, with exponentiation and the use of the percent sign to denot |
https://en.wikipedia.org/wiki/Bird%20rarities%20committee | A bird rarities committee or bird records committee is a committee which exists to validate records of rare birds in a particular country or region.
Many countries have national rarities committees; in some areas, such as Europe, coverage is near-complete at a national level. European national committees are all members of the Association of European Rarities Committees.
Some countries have committees covering more localised areas - e.g. in the United States, most states have their own state records committee, and in Britain, each county has its own county records committee.
A records committee differs from a list committee in that the latter just compile a list of the species found in an area, and do not typically assess every individual record of the rare species.
See also
List of the member committees of the Association of European Rarities Committees
Ornithological organizations |
https://en.wikipedia.org/wiki/John%20Guttag | John Vogel Guttag (born March 6, 1949) is an American computer scientist, professor, and former head of the department of electrical engineering and computer science at MIT.
Education and career
John Guttag was raised in Larchmont, New York, the son of Irwin Guttag (1916–2005) and Marjorie Vogel Guttag.
John Vogel Guttag received a bachelor's degree in English from Brown University in 1971, and a master's degree in applied mathematics from Brown in 1972. In 1975, he received a doctorate in Computer Science from the University of Toronto. He was a member of the faculty at the University of Southern California from 1975 to 1978, and joined the Massachusetts Institute of Technology faculty in 1979.
From 1993 to 1998, he served as associate department head for computer science of MIT's electrical engineering and computer science Department. From January 1999 through August 2004, he served as head of that department. EECS, with approximately 2000 students and 125 faculty members, is the largest department at MIT.
He helped student Vanu Bose start a company with software-defined radio technology developed at MIT.
Guttag also co-heads the MIT Computer Science and Artificial Intelligence Laboratory's Networks and Mobile Systems Group. This group studies issues related to computer networks, applications of networked and mobile systems, and advanced software-based medical instrumentation and decision systems. He has also done research, published, and lectured in the areas of software engineering, mechanical theorem proving, hardware verification, compilation, software radios, and medical computing.
Guttag serves on the board of directors of Empirix and Avid Technology, and on the board of trustees of the Massachusetts General Hospital Institute of Health Professions. He is a member of the American Academy of Arts and Sciences. In 2006 he was inducted as a fellow of the Association for Computing Machinery.
He is one of the founders of Health[at]Scale Technologies, a mach |
https://en.wikipedia.org/wiki/Theoretical%20computer%20science | Theoretical computer science (TCS) is a subset of general computer science and mathematics that focuses on mathematical aspects of computer science such as the theory of computation, formal language theory, the lambda calculus and type theory.
It is difficult to circumscribe the theoretical areas precisely. The ACM's Special Interest Group on Algorithms and Computation Theory (SIGACT) provides the following description:
History
While logical inference and mathematical proof had existed previously, in 1931 Kurt Gödel proved with his incompleteness theorem that there are fundamental limitations on what statements could be proved or disproved.
Information theory was added to the field with a 1948 mathematical theory of communication by Claude Shannon. In the same decade, Donald Hebb introduced a mathematical model of learning in the brain. With mounting biological data supporting this hypothesis with some modification, the fields of neural networks and parallel distributed processing were established. In 1971, Stephen Cook and, working independently, Leonid Levin, proved that there exist practically relevant problems that are NP-complete – a landmark result in computational complexity theory.
With the development of quantum mechanics in the beginning of the 20th century came the concept that mathematical operations could be performed on an entire particle wavefunction. In other words, one could compute functions on multiple states simultaneously. This led to the concept of a quantum computer in the latter half of the 20th century that took off in the 1990s when Peter Shor showed that such methods could be used to factor large numbers in polynomial time, which, if implemented, would render some modern public key cryptography algorithms like RSA insecure.
Modern theoretical computer science research is based on these basic developments, but includes many other mathematical and interdisciplinary problems that have been posed, as shown below:
Topics
Algorithms
An |
https://en.wikipedia.org/wiki/Institute%20of%20Physics%2C%20Bhubaneswar | Institute of Physics, Bhubaneswar () is an autonomous research institution of the Department of Atomic Energy (DAE), Government of India. The institute was founded by Professor Bidhu Bhusan Das, who was Director of Public Instruction, Odisha, at that time. Das set up the institute in 1972, supported by the Government of Odisha under the patronage of Odisha's education minister Banamali Patnaik, and chose Dr. Trilochan Pradhan as its first director, when the Institute started theoretical research programs in the various branches of physics. Other notable physicists in the institute's early days included Prof. T. P. Das, of SUNY, Albany, New York, USA and Prof. Jagdish Mohanty of IIT Kanpur and Australian National University, Canberra. In 1981, the Institute moved to its present campus near Chandrasekharpur, Bhubaneswar. It was taken over by the Department of Atomic Energy, India on 25 March 1985 and started functioning as an autonomous body.
Research
The institute conducts research in theoretical and experimental physics.
Theoretical physics
Research areas in theoretical physics include condensed matter theory, nuclear and high energy physics. High-energy theorists at IOP have made contributions to field theories, phase transitions in early universe, cosmology, the Planck scale phenomena, string theory and high-energy nuclear physics such as qgp, equation of state and nuclear astrophysics, neutron stars, high-energy phenomenology and neutrino physics phenomenology. In theoretical condensed matter physics, research is centered on disordered systems, magnetism, superconductivity, low-dimensional systems, statistical physics, strongly correlated systems, phase transitions, clusters and nanomaterials.
Experimental physics
The experimental physics group encompasses accelerator-based research for advanced chemical and radioisotope analysis. The ion beam laboratory (IBL) is equipped with a 3MV tandem accelerator (NEC 9SDH-2). Research at the IBL includes Rutherford bac |
https://en.wikipedia.org/wiki/Hopper%20%28DVR%29 | Hopper is a line of digital video recording (DVR) set-top boxes offered by the U.S. direct-broadcast satellite television provider Dish Network. First introduced at Consumer Electronics Show in January 2012, the Hopper was released in March 2012 as a component of the provider's whole-home DVR system, which networks the main Hopper unit with smaller "Joey" set-top boxes to form a client-server architecture.
The Hopper is primarily distinguished by its "Primetime Anytime" functionality, which automatically records primetime programming off the four major U.S. television networks, while a later software update added "AutoHop", which allows commercials to automatically be removed from these recordings. The following year at the Consumer Electronics Show, Dish Network introduced an updated version known as Hopper with Sling, which integrates Slingbox place-shifting technology directly into the box.
Both versions of the Hopper were met with universal praise by technology publications, particularly surrounding its "PrimeTime Anytime" functionality, the AutoHop feature, integration with smartphones and tablets, and the addition of built-in place-shifting to its second iteration. However, despite the positive reception, the Hopper became the subject of a copyright lawsuit filed by major U.S. broadcasters shortly after its release, who questioned the legality of the AutoHop feature by considering it to be an attack on their business model. Although unsuccessful in its lawsuits against Dish Network, ABC (Disney), CBS and Fox Broadcasting Company have since used carriage agreements and other settlements to impose requirements for AutoHop to be disabled on their respective primetime programs for a period after their original air date.
The Hopper with Sling model was the subject of a related controversy when its "Best in Show" award at CES was vetoed by CBS—whose website CNET issued the award on behalf of CES organizers, because it was a party of active litigation with Dish Ne |
https://en.wikipedia.org/wiki/WineMaker%20Magazine | WineMaker Magazine is an American magazine, particularly concerned with the process of home winemaking. The magazine is published six times annually from offices in Manchester Village, Vermont. WineMaker was launched in 1999 and each issue includes wine recipes, how-to projects and advice columns. WineMaker magazine also runs the annual WineMaker International Amateur Wine Competition.
According to Tim Patterson in his book Home Winemaking For Dummies, "as hobby magazines go, this one is serious. It covers everything from kit wines to home vineyards and contains technically solid articles that get reviewed before they get published."
WineMaker’s sister publication is Brew Your Own magazine. |
https://en.wikipedia.org/wiki/Genocchi%20number | In mathematics, the Genocchi numbers Gn, named after Angelo Genocchi, are a sequence of integers that satisfy the relation
The first few Genocchi numbers are 0, −1, −1, 0, 1, 0, −3, 0, 17 , see .
Properties
The generating function definition of the Genocchi numbers implies that they are rational numbers. In fact, G2n+1 = 0 for n ≥ 1 and (−1)nG2n is an odd positive integer.
Genocchi numbers Gn are related to Bernoulli numbers Bn by the formula
Combinatorial interpretations
The exponential generating function for the signed even Genocchi numbers (−1)nG2n is
They enumerate the following objects:
Permutations in S2n−1 with descents after the even numbers and ascents after the odd numbers.
Permutations π in S2n−2 with 1 ≤ π(2i−1) ≤ 2n−2i and 2n−2i ≤ π(2i) ≤ 2n−2.
Pairs (a1,…,an−1) and (b1,…,bn−1) such that ai and bi are between 1 and i and every k between 1 and n−1 occurs at least once among the ai's and bi's.
Reverse alternating permutations a1 < a2 > a3 < a4 >…>a2n−1 of [2n−1] whose inversion table has only even entries.
See also
Euler number |
https://en.wikipedia.org/wiki/Backyard%20Wildlife%20Habitat | The Backyard Wildlife Habitat is a program of the National Wildlife Federation that encourages homeowners in the United States to manage their gardens and yards as a wildlife garden, with the goal of maintaining healthy and diverse animal habitats and ecosystems. The program began in 1973. By 1998, it had impacted more than 21,000 yards and, as of 2006, has certified over 60,000 'backyards'.
Certification
To be a certified Backyard Wildlife Habitat, a garden or yard, or any outdoor space from a balcony up to a multi-acre tract of land, must offer food, water, shelter, and a place for raising young to beneficial insects or animals. Over time the Federation has introduced variants or expansions of the program for schoolyards and for communities.
In order for a backyard to be certified as a Backyard Wildlife Habitat by the National Wildlife Federation, the space must do all of the following: provide food, water, cover, a place to raise young, and be maintained in a way that has a positive effect on the health of the soil, air, water, and habitat for native wildlife. More specifically, the presence of native forbs, shrubs, and trees is necessary to provide food. Water can be supplied by natural features such as a streams, ponds, or wetlands, or by human-made features such as bird baths. Native vegetation can also provide cover and places for wildlife to raise their young, as can brush piles or dead trees. With all of these features in place, it is crucial that the land be cared for thoughtfully and as naturally as possible. Avoid the use of chemical pesticides and fertilizers, reduce the area that turf grass occupies, utilize mulch obtained from sustainable forestry practices, and minimize water use in order to maintain the integrity of the soil, air, and water in and outside of the habitat.
Effectiveness and success
Prior to 2004 there was no scientific study as to whether backyard habitats actually help butterflies. A study published in 2004 of the effect |
https://en.wikipedia.org/wiki/Faultless%20disagreement | A faultless disagreement is a disagreement when Party A states that P is true, while Party B states that non-P is true, and neither party is at fault. Disagreements of this kind may arise in areas of evaluative discourse, such as aesthetics, justification of beliefs or moral values, etc. A representative example is that John says Paris is more interesting than Rome, while Bob claims Rome is more interesting than Paris. Furthermore, in the case of a faultless disagreement, it is possible that if any party gives up their claim, there will be no improvement in the position of any of them.
Within the framework of formal logic it is impossible that both P and not-P are true, and it was attempted to justify faultless disagreements within the framework of relativism of the Truth, Max Kölbel and Sven Rosenkranz present arguments to the point that genuine faultless disagreements are impossible. However, defenses of faultless disagreement, and of alethic relativism more generally, continue to be made by critics of formal logic as it is currently constructed. |
https://en.wikipedia.org/wiki/Glossary%20of%20biology | This glossary of biology terms is a list of definitions of fundamental terms and concepts used in biology, the study of life and of living organisms. It is intended as introductory material for novices; for more specific and technical definitions from sub-disciplines and related fields, see Glossary of cell biology, Glossary of genetics, Glossary of evolutionary biology, Glossary of ecology, Glossary of environmental science and Glossary of scientific naming, or any of the organism-specific glossaries in :Category:Glossaries of biology.
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Index of biology articles
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Glossaries of sub-disciplines and related fields:
Glossary of botany
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Glossary of genetics
Glossary of ichthyology
Glossary of ornithology
Glossary of scientific naming
Glossary of speciation
Glossary of virology |
https://en.wikipedia.org/wiki/When%20Vikings%20Attack%21 | When Vikings Attack! is a fighting video game by British studio Clever Beans. The game was released on November 6, 2012, as a downloadable game for the PlayStation 3 and supports Sony's cross-play feature on the PS Vita. It is included on the "Best of PlayStation Network Vol. 1" compilation disc, released June 18, 2013.
Gameplay
When Vikings Attack! plays like an arena melee-brawler game.
The only weapons are thrown objects. Players control a small group of civilians fighting hordes of vikings. The objective is to pick up objects and throw them in order to knock out enemies. A single hit is required to knock out an opponent's troop. Each time an object collides with a figure, they're knocked out and excluded from the group, but larger or wide objects may even knock out an entire group, resulting in the player being eliminated. Lost civilians can be replaced by recruiting stray people roaming around the arena. The game also features special items to be thrown such as explosive bombs for an area of effect attack.
The game has a campaign mode supporting up to four player co-op. There's a multiplayer option with a few game modes such as last man standing and survival mode. The game also features collection extra for viewing collected citizens of different outfits and movies.
Reception
The game received mixed to fairly positive reviews. IGN gave the game a 6.5, praising the unique gameplay, but claims it gets repetitive after a while. |
https://en.wikipedia.org/wiki/Prunus%20nigra | Prunus nigra, the Canada plum, Canadian plum, or black plum, is a species of Prunus native to eastern North America.
Description
Prunus nigra is a deciduous shrub or small tree growing to tall with a trunk up to in diameter, with a low-branched, dense crown of stiff, rigid, branches. The bark is gray-brown, older layers coming off in thick plates. The branchlets are bright green at first, later become dark brown tinged with red, and spiny. The winter buds are chestnut brown, long-pointed at the tip, up to long.
The leaves are alternate, simple, and oblong-ovate or obovate, long and broad, wedge-shaped, slightly heart-shaped, or rounded at base, doubly crenaulate-serrate, abruptly contracted to a narrow point at the apex, feather-veined, midrib conspicuous; they emerge from the bud convolute, downy, slightly tinged with red, are smooth, becoming bright green above and paler beneath when full grown. The leaf petioles are stout, bearing two large dark glands and early deciduous, lanceolate, and three to five-lobed stipules.
The flowers are diameter, with five rounded petals, white fading to pale pink, with a more or less irregularly notched margin; they are slightly fragrant, borne in three to four-flowered umbels, with short, thick peduncles, and appear before the leaves in mid to late spring. The flower stalks are slender and dark red. The calyx is conic, dark red, five-lobed, the lobes acute, finally reflexed, glandular, smooth on the inner surface, imbricate in bud, ovate, with short claws, imbricate in bud. There are 15–20 stamens, inserted on the calyx tube; filaments thread-like; anthers purplish, introrse, two-celled; cells opening longitudinally; the pistil has a superior ovary in the bottom of calyx tube, one-celled, with two ovules.
The fruit is an oblong-oval drupe, long with a tough, thick, orange red skin, free from bloom, yellow flesh adherent to the stone; the stone oval, compressed. It matures in late summer or early autumn. The cotyledons a |
https://en.wikipedia.org/wiki/Alex%20Kipman | Alex Kipman (born 1979) is a Brazilian engineer. He was the lead developer of the Microsoft HoloLens smartglasses and helped develop the Xbox Kinect.
Biography
Kipman was born in Curitiba in 1979. The son of a Brazilian diplomat, Kipman grew up around the world. When he was seven or eight, he learned how to program the Atari 2600. Later on he would go to RIT, graduating in 2001 with a degree in software engineering and joined Microsoft that same year, starting development on Microsoft's integrated development environment (IDE) Visual Studio. Starting 2005, he helped in the development of Microsoft Windows, until joining the Xbox department in 2008, where he oversaw the acquisition of the technology for the Xbox Kinect from an Israeli company, PrimeSense. The product was finished two years later.
In 2011, Time magazine named him to its list of its 100 Most Influential People in the World, a list consisting of leaders, artists, innovators, icons and heroes. In a subsequent interview with Fast Company, he said "Software is the only art form in existence that is not bound by the confines of physics." In 2012 he was named Inventor of the Year by the Intellectual Property Owners Association.
In 2013, Kipman gave the commencement speech at his alma mater, the Rochester Institute of Technology (RIT).
In 2016, he gave a Ted Talk on mixed reality, called "A futuristic vision of the age of Holograms". In a 2017 interview with Alice Bonasio, he emphasized his passion for mixed reality, stating how it gives him a sense of "displacement superpowers". During the Hololens 2 reveal at the Mobile World Congress in 2019, Alex Kipman talked about how the Hololens 2 would be the "next era" of mixed reality, making it more culturally relevant.
In 2019 while he was developing metaverse technologies, the Smithsonian Institution in Washington, D.C named Kipman the winner of an American Ingenuity Award, calling him a pioneer of holographic and augmented reality technology. Later that y |
https://en.wikipedia.org/wiki/Depth-first%20search | Depth-first search (DFS) is an algorithm for traversing or searching tree or graph data structures. The algorithm starts at the root node (selecting some arbitrary node as the root node in the case of a graph) and explores as far as possible along each branch before backtracking. Extra memory, usually a stack, is needed to keep track of the nodes discovered so far along a specified branch which helps in backtracking of the graph.
A version of depth-first search was investigated in the 19th century by French mathematician Charles Pierre Trémaux as a strategy for solving mazes.
Properties
The time and space analysis of DFS differs according to its application area. In theoretical computer science, DFS is typically used to traverse an entire graph, and takes time where is the number of vertices and the number of edges. This is linear in the size of the graph. In these applications it also uses space in the worst case to store the stack of vertices on the current search path as well as the set of already-visited vertices. Thus, in this setting, the time and space bounds are the same as for breadth-first search and the choice of which of these two algorithms to use depends less on their complexity and more on the different properties of the vertex orderings the two algorithms produce.
For applications of DFS in relation to specific domains, such as searching for solutions in artificial intelligence or web-crawling, the graph to be traversed is often either too large to visit in its entirety or infinite (DFS may suffer from non-termination). In such cases, search is only performed to a limited depth; due to limited resources, such as memory or disk space, one typically does not use data structures to keep track of the set of all previously visited vertices. When search is performed to a limited depth, the time is still linear in terms of the number of expanded vertices and edges (although this number is not the same as the size of the entire graph because some ve |
https://en.wikipedia.org/wiki/Yuval%20Peres | Yuval Peres (; born 5 October 1963) is a mathematician known for his research in probability theory, ergodic theory, mathematical analysis, theoretical computer science, and in particular for topics such as fractals and Hausdorff measure, random walks, Brownian motion, percolation and Markov chain mixing times. He was born in Israel and obtained his Ph.D. at the Hebrew University of Jerusalem in 1990 under the supervision of Hillel Furstenberg. He was a faculty member at the Hebrew University and the University of California at Berkeley, and a Principal Researcher at Microsoft Research in Redmond, Washington. Peres has been accused of sexual harassment by several female scientists.
Career
After his Ph.D. Peres had postdoctoral positions at Stanford and Yale.
In 1993 Peres joined the statistics department at UC Berkeley. He later became a professor in both the mathematics and statistics departments. He was also a professor at the Hebrew University.
In 2006 Peres joined the Theory Group of Microsoft Research. By 2011 he was principal researcher at Microsoft Research and manager of the Microsoft Research Theory Group, an affiliate professor of mathematics at the University of Washington and an adjunct professor at the University of California, Berkeley.
Recognition
Peres was awarded the Rollo Davidson Prize in 1995 and the Loève Prize in 2001. The work that led to the Loève Prize was surveyed in the Notices of the American Mathematical Society: "A key breakthrough was the observation that certain (hard to prove) intersection properties for Brownian motion and random walks are in fact equivalent to (easier to prove) survival properties of branching processes. This led ultimately to deep work on sample path properties of Brownian motion; for instance, on the fractal dimension of the frontier of two-dimensional Brownian motion and precise study of its thick and thin points and cover times."
Peres was an invited speaker at the International Congress of Mathematicians i |
https://en.wikipedia.org/wiki/Wine%20lake | Wine lake is a cultural phrase referring to the phenomenon of perceived overproduction of wine in the European Union. The phenomenon first came in perception & persistence around 2005 to 2007. The EU's Common Agricultural Policy contained a number of subsidies for wine producers, leading to a supply glut. This surplus forced an overhaul of EU farm policies.
In 2007 it was reported that for the previous several vintages, Europe had been producing 1.7 Billion more bottles of wine than they sold. Hundreds of millions of bottles of wine had been turned into industrial alcohol every year, a practice that had sometimes been described as 'emergency distillation' at a cost to taxpayers of €500 million per year. A major contributor was reported to be Languedoc-Roussillon wine production, which used one third of the grapes grown in France.
One of the proposed remedies to wine lake was Plan Bordeaux, an initiative introduced in 2005 by the French vintners association ONIVINS to reduce France's production and raise prices. Part of the plan was to uproot of the of vineyards in Bordeaux. The proposed plan was met with some resistance.
In 2020, wine growers warned that the EU risked another massive surplus due to the effects of the COVID-19 pandemic, particularly the restaurant closures. The growers called for additional subsidies to distill surplus wine.
In 2023, €200 million was again earmarked for conversion of surplus wine into industrial products.
See also
Butter mountain
Crop destruction
Artificial scarcity
Deer Terrace Pavilion, site of a historical 'Lake of Wine' in China |
https://en.wikipedia.org/wiki/Buellia%20frigida | Buellia frigida is a species of saxicolous (rock-dwelling), crustose lichen in the family Caliciaceae. It was first described from samples collected from the British National Antarctic Expedition of 1901–1904. It is endemic to maritime and continental Antarctica, where it is common and widespread, at altitudes up to about . This resilient lichen has a characteristic appearance, typically featuring shades of grey and black divided into small polygonal patterns. The crusts can generally grow up to in diameter (smaller sizes are more common), although neighbouring individuals may coalesce to form larger crusts. One of the defining characteristics of the lichen is a textured surface with deep cracks, creating the appearance of radiating . These lobes, bordered by shallower fissures, give the lichen a unique visual texture.
In addition to its striking appearance, Buellia frigida exhibits remarkable adaptability to the harsh Antarctic climate. The lichen has an extremely slow growth rate, estimated to be less than per century. Because of its ability to not only endure but to thrive in one of the Earth's coldest, harshest environments, Buellia frigida has been used frequently as a model organism in astrobiology research. This lichen has been exposed to conditions simulating those encountered in space and on celestial bodies like Mars, including vacuum, UV radiation, and extreme dryness. B. frigida has demonstrated resilience to these space-related stressors, making it a candidate for studying how life can adapt to and potentially survive in the extreme environments found beyond Earth.
Taxonomy
The lichen was formally described as a new species in 1910 by the British botanist Otto Derbishire. The type specimen were collected in 1902 by Reginald Koettlitz from Granite Harbour in McMurdo Sound; they were found growing on tuff. This and other samples were obtained as part of the British National Antarctic Expedition of 1901–1904. The of the lichen was as follows (translat |
https://en.wikipedia.org/wiki/UNIQUAC | In statistical thermodynamics, UNIQUAC (a portmanteau of universal quasichemical) is an activity coefficient model used in description of phase equilibria.
The model is a so-called lattice model and has been derived from a first order approximation of interacting molecule surfaces. The model is, however, not fully thermodynamically consistent due to its two-liquid mixture approach. In this approach the local concentration around one central molecule is assumed to be independent from the local composition around another type of molecule.
The UNIQUAC model can be considered a second generation activity coefficient because its expression for the excess Gibbs energy consists of an entropy term in addition to an enthalpy term. Earlier activity coefficient models such as the Wilson equation and the non-random two-liquid model (NRTL model) only consist of enthalpy terms.
Today the UNIQUAC model is frequently applied in the description of phase equilibria (i.e. liquid–solid, liquid–liquid or liquid–vapor equilibrium). The UNIQUAC model also serves as the basis of the development of the group contribution method UNIFAC, where molecules are subdivided into functional groups. In fact, UNIQUAC is equal to UNIFAC for mixtures of molecules, which are not subdivided; e.g. the binary systems water-methanol, methanol-acryonitrile and formaldehyde-DMF.
A more thermodynamically consistent form of UNIQUAC is given by the more recent COSMOSPACE and the equivalent GEQUAC model.
Equations
Like most local composition models, UNIQUAC splits excess Gibbs free energy into a combinatorial and a residual contribution:
The calculated activity coefficients of the ith component then split likewise:
The first is an entropic term quantifying the deviation from ideal solubility as a result of differences in molecule shape. The latter is an enthalpic correction caused by the change in interacting forces between different molecules upon mixing.
Combinatorial contribution
The combinatori |
https://en.wikipedia.org/wiki/Boomerang%20attack | In cryptography, the boomerang attack is a method for the cryptanalysis of block ciphers based on differential cryptanalysis. The attack was published in 1999 by David Wagner, who used it to break the COCONUT98 cipher.
The boomerang attack has allowed new avenues of attack for many ciphers previously deemed safe from differential cryptanalysis.
Refinements on the boomerang attack have been published: the amplified boomerang attack, and the rectangle attack.
Due to the similarity of a Merkle–Damgård construction with a block cipher, this attack may also be applicable to certain hash functions such as MD5.
The attack
The boomerang attack is based on differential cryptanalysis. In differential cryptanalysis, an attacker exploits how differences in the input to a cipher (the plaintext) can affect the resultant difference at the output (the ciphertext). A high probability "differential" (that is, an input difference that will produce a likely output difference) is needed that covers all, or nearly all, of the cipher. The boomerang attack allows differentials to be used which cover only part of the cipher.
The attack attempts to generate a so-called "quartet" structure at a point halfway through the cipher. For this purpose, say that the encryption action, E, of the cipher can be split into two consecutive stages, E0 and E1, so that E(M) = E1(E0(M)), where M is some plaintext message. Suppose we have two differentials for the two stages; say,
for E0, and
for E1−1 (the decryption action of E1).
The basic attack proceeds as follows:
Choose a random plaintext and calculate .
Request the encryptions of and to obtain and
Calculate and
Request the decryptions of and to obtain and
Compare and ; when the differentials hold, .
Application to specific ciphers
One attack on KASUMI, a block cipher used in 3GPP, is a related-key rectangle attack which breaks the full eight rounds of the cipher faster than exhaustive search (Biham et al., 2005). The attack req |
https://en.wikipedia.org/wiki/Local%20reference%20frame | In theoretical physics, a local reference frame (local frame) refers to a coordinate system or frame of reference that is only expected to function over a small region or a restricted region of space or spacetime.
The term is most often used in the context of the application of local inertial frames to small regions of a gravitational field. Although gravitational tidal forces will cause the background geometry to become noticeably non-Euclidean over larger regions, if we restrict ourselves to a sufficiently small region containing a cluster of objects falling together in an effectively uniform gravitational field, their physics can be described as the physics of that cluster in a space free from explicit background gravitational effects.
Equivalence principle
When constructing his general theory of relativity, Einstein made the following observation: a freely falling object in a gravitational field will not be able to detect the existence of the field by making local measurements ("a falling man feels no gravity"). Einstein was then able to complete his general theory by arguing that the physics of curved spacetime must reduce over small regions to the physics of simple inertial mechanics (in this case special relativity) for small freefalling regions.
Einstein referred to this as "the happiest idea of my life".
Laboratory frame
In physics, the laboratory frame of reference, or lab frame for short, is a frame of reference centered on the laboratory in which the experiment (either real or thought experiment) is done. This is the reference frame in which the laboratory is at rest. Also, this is usually the frame of reference in which measurements are made, since they are presumed (unless stated otherwise) to be made by laboratory instruments. An example of instruments in a lab frame, would be the particle detectors at the detection facility of a particle accelerator.
See also
Breit frame
Center-of-mass frame
Frame bundle
Inertial frame of reference
Local coo |
https://en.wikipedia.org/wiki/Cyclic%20vector | An operator A on an (infinite dimensional) Banach space or Hilbert space H has a cyclic vector f if the vectors f, Af, A2f,... span H. Equivalently, f is a cyclic vector for A in case the set of all vectors of the form p(A)f, where p varies over all polynomials, is dense in H.
See also
Cyclic and separating vector |
https://en.wikipedia.org/wiki/Silphium | Silphium (also known as silphion, laserwort, or laser) is an unidentified plant that was used in classical antiquity as a seasoning, perfume, aphrodisiac, and medicine.
It was also used as a contraceptive by ancient Greeks and Romans. It was the essential item of trade from the ancient North African city of Cyrene, and was so critical to the Cyrenian economy that most of their coins bore a picture of the plant. The valuable product was the plant's resin (laser, laserpicium, or lasarpicium).
Silphium was an important species in classical antiquity, as evidenced by the Egyptians and Knossos Minoans developing a specific glyph to represent the silphium plant. It was used widely by most ancient Mediterranean cultures; the Romans, who mentioned the plant in poems or songs, considered it "worth its weight in denarii" (silver coins), or even gold. Legend said that it was a gift from the god Apollo.
The exact identity of silphium is unclear. It was claimed to have become extinct in Roman times. It is commonly believed to be a fennel relative in the genus Ferula, perhaps a variety of giant fennel. The extant plants Margotia gummifera, Ferula tingitana, and Ferula drudeana have been suggested as other possibilities. Another theory is that it was simply a high quality variety of asafoetida, a common spice in the Roman Empire. The two spices were considered the same by many Romans including the geographer Strabo. In 2021, a study from Istanbul University identified Ferula drudeana as a likely candidate for silphium, matching both the appearance of silphium in descriptions and the spice-like gum-resin of silphium, though without a surviving sample no genetic analysis can be made.
Identity and extinction
The identity of silphium is highly debated. It is generally considered to belong to the genus Ferula, as an extinct or living species. The currently extant plants , Ferula tingitana, Ferula narthex, Ferula drudeana, and Thapsia garganica have been suggested as possible ide |
https://en.wikipedia.org/wiki/Li-Fi | Li-Fi (also written as LiFi) is a wireless communication technology which utilizes light to transmit data and position between devices. The term was first introduced by Harald Haas during a 2011 TEDGlobal talk in Edinburgh.
Li-Fi is a light communication system that is capable of transmitting data at high speeds over the visible light, ultraviolet, and infrared spectrums. In its present state, only LED lamps can be used for the transmission of data in visible light.
In terms of its end user, the technology is similar to Wi-Fi — the key technical difference being that Wi-Fi uses radio frequency to induce an electric tension in an antenna to transmit data, whereas Li-Fi uses the modulation of light intensity to transmit data. Li-Fi is able to function in areas otherwise susceptible to electromagnetic interference (e.g. aircraft cabins, hospitals, or the military).
Technology details
Li-Fi is a derivative of optical wireless communications (OWC) technology, which uses light from light-emitting diodes (LEDs) as a medium to deliver network, mobile, high-speed communication in a similar manner to Wi-Fi. The Li-Fi market was projected to have a compound annual growth rate of 82% from 2013 to 2018 and to be worth over $6 billion per year by 2018. However, the market has not developed as such and Li-Fi remains with a niche market.
Visible light communications (VLC) works by switching the current to the LEDs off and on at a very high speed, beyond the human eye's ability to notice. Technologies that allow roaming between various Li-Fi cells, also known as handover, may allow to seamlessly transition between Li-Fi. The light waves cannot penetrate walls which translates to a much shorter range, and a lower hacking potential, relative to Wi-Fi. Direct line of sight is not always necessary for Li-Fi to transmit a signal and light reflected off walls can achieve 70 Mbit/s.
Li-Fi can potentially be useful in electromagnetic sensitive areas without causing electromagnetic in |
https://en.wikipedia.org/wiki/Victor%20Vladimirovich%20Petryashov | Victor Vladimirovich Petryashov (16 March 1956 - 2 July 2018) was a Russian zoologist, carcinologist, hydrobiologist and biogeographer. His scientific research focused on taxonomy and distribution of malacostracan crustaceans, particularly orders Mysida, Lophogastrida and Leptostraca, and marine biogeography and hydrobiology of Arctic, Antarctic and temperate seas of the World, and he published over 120 works. V.V. Petryashov spent all his professional life in St. Petersburg in the Zoological Institute of the Russian Academy of Sciences. As a senior researcher he also curated the malacostracan crustacean collection of the Zoological Institute.
Named taxa
Mysida:
Paracanthomysis shikhotaniensis Petrjashov, 1983
Stylomysis arcticoglacialis (Petryashov, 1990) (originally Mysis arcticoglacialis Petryashov, 1990)
Michthyops arcticus Petryashov, 1993
Meterythrops muranous Petryashov, 2015
Stellamblyops Petryashov et Frutos, 2017
Stellamblyops vassilenkoae Petryashov et Frutos, 2017
Lophogastrida:
Neognathophausia Petryashov, 1992
Fagegnathophausia Petryashov, 2015
Leptostraca:
Pseudonebaliopsis Petryashov, 1996
Pseudonebaliopsis atlantica Petryashov, 1996
Sarsinebalia pseudotyphlops Petryashov, 2016
Nebaliella kurila Petryashov, 2016
Nebaliella ochotica Petryashov, 2017
Taxa dedicated to V.V. Petryashov
Boreomysis (Petryashovia) Daneliya, 2023 (Mysida: Mysidae: Boreomysinae) |
https://en.wikipedia.org/wiki/Equativ | Equativ (formerly known as Smart AdServer) is a French advertising technology company. Created in 2001 as part of Aufeminin, it was bought by private-equity fund Cathay Capital in 2015, and then by private-equity fund Capital Croissance for a secondary LBO in 2021. It operates mostly in the US, Europe, Latin America and Asia.
History
Equativ was created in 2001 by aufeminin.com in order to manage advertisements on the publisher's websites. It became an independent company within the same group in 2005, then expanded locally and internationally
Axel Springer, the largest digital publishing house in Europe, bought AuFeminin in 2007. Following that take-over, Equativ expanded into Europe, Latin America and the United States. In 2015, Axel Springer sold the company to private equity fund Cathay Capital for 37 million €. In 2021 private equity fund Capital Croissance became the new majority shareholder of the company for a secondary LBO, in a bid to accelerate the development of the company in the United States and in connected TV.
The company operates an adserver, an SSP and a DSP and specializes in solutions for Advanced TV and premium publishers. As of 2023, the company operates on 4 continents with a management team split between Paris, New York and London.
In February 2023, Equativ is bought by Private Equity fund Bridgepoint Group, in a transaction valued "at more than €300m".
Acquisitions
In 2019, Equativ acquired LiquidM, a global Demand Side Platform (DSP) based in Berlin.
In 2021, Equativ acquired DynAdmic, a Cookie-Free CTV and Video Advertising Platform providing Managed DSP services.
In 2022, Equativ acquired Nowtilus, a German Advanced TV specialist.
See also
Supply-side platform
Real-Time Bidding |
https://en.wikipedia.org/wiki/Ignicoccus | Ignicoccus is a genus of hyperthermophillic Archaea living in marine hydrothermal vents. They were discovered in samples taken at the Kolbeinsey Ridge north of Iceland, as well as at the East Pacific Rise (at 9 degrees N, 104 degrees W) in 2000.
Systematics
According to the comparisons of 16S rRNA genes, Ignicoccus represents a new, deeply branching lineage within the family of the Desulfurococcaceae.
Three species are known: I. islandicus, I. pacificus and I. hospitalis strain KIN4I.
Cell structure
The archaea of the genus Ignicoccus have tiny coccoid cells with a diameter of about 2 µm, that exhibit a smooth surface, an outer membrane and no S-layer.
They have a previously unknown cell envelope structure—a cytoplasmic membrane, a periplasmic space (with a variable width of 20 to 400 nm, containing membrane-bound vesicles), and an outer membrane (approximately 10 nm wide, resembling the outer membrane of gram-negative bacteria). The latter contains numerous tightly, irregularly packed single particles (about 8 nm in diameter) and pores with a diameter of 24 nm, surrounded by tiny particles, arranged in a ring (with a diameter of 130 nm) and clusters of up to eight particles 12 nm in diameter each.
The two layers of membrane previously reported are actually a type of endomembrane system consisting of cytoplasmic protrusions. In I. hospitalis, these structures harbor the endosymbiotic archaeon Nanoarchaeum equitans.
Physiology
Ignicocci live in a temperature range of 70–98 °C (optimum around 90 °C). They gain energy by reduction of elemental sulfur to hydrogen sulfide using molecular hydrogen as the electron donor. A unique symbiosis with (or parasitism by) Nanoarchaeum equitans has also been reported.
Phylogeny
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI)
See also
List of Archaea genera |
https://en.wikipedia.org/wiki/Free%20Boolean%20algebra | In mathematics, a free Boolean algebra is a Boolean algebra with a distinguished set of elements, called generators, such that:
Each element of the Boolean algebra can be expressed as a finite combination of generators, using the Boolean operations, and
The generators are as independent as possible, in the sense that there are no relationships among them (again in terms of finite expressions using the Boolean operations) that do not hold in every Boolean algebra no matter which elements are chosen.
A simple example
The generators of a free Boolean algebra can represent independent propositions. Consider, for example, the propositions "John is tall" and "Mary is rich". These generate a Boolean algebra with four atoms, namely:
John is tall, and Mary is rich;
John is tall, and Mary is not rich;
John is not tall, and Mary is rich;
John is not tall, and Mary is not rich.
Other elements of the Boolean algebra are then logical disjunctions of the atoms, such as "John is tall and Mary is not rich, or John is not tall and Mary is rich". In addition there is one more element, FALSE, which can be thought of as the empty disjunction; that is, the disjunction of no atoms.
This example yields a Boolean algebra with 16 elements; in general, for finite n, the free Boolean algebra with n generators has 2n atoms, and therefore elements.
If there are infinitely many generators, a similar situation prevails except that now there are no atoms. Each element of the Boolean algebra is a combination of finitely many of the generating propositions, with two such elements deemed identical if they are logically equivalent.
Another way to see why the free Boolean algebra on an n-element set has elements is to note that each element is a function from n bits to one. There are possible inputs to such a function and the function will choose 0 or 1 to output for each input, so there are possible functions.
Category-theoretic definition
In the language of category theory, free Boolean a |
https://en.wikipedia.org/wiki/Nonhypotenuse%20number | In mathematics, a nonhypotenuse number is a natural number whose square cannot be written as the sum of two nonzero squares. The name stems from the fact that an edge of length equal to a nonhypotenuse number cannot form the hypotenuse of a right angle triangle with integer sides.
The numbers 1, 2, 3 and 4 are all nonhypotenuse numbers. The number 5, however, is not a nonhypotenuse number as 52 equals 32 + 42.
The first fifty nonhypotenuse numbers are:
1, 2, 3, 4, 6, 7, 8, 9, 11, 12, 14, 16, 18, 19, 21, 22, 23, 24, 27, 28, 31, 32, 33, 36, 38, 42, 43, 44, 46, 47, 48, 49, 54, 56, 57, 59, 62, 63, 64, 66, 67, 69, 71, 72, 76, 77, 79, 81, 83, 84
Although nonhypotenuse numbers are common among small integers, they become more-and-more sparse for larger numbers. Yet, there are infinitely many nonhypotenuse numbers, and the number of nonhypotenuse numbers not exceeding a value x scales asymptotically with x/.
The nonhypotenuse numbers are those numbers that have no prime factors of the form 4k+1. Equivalently, they are the number that cannot be expressed in the form where K, m, and n are all positive integers. A number whose prime factors are not of the form 4k+1 cannot be the hypotenuse of a primitive integer right triangle (one for which the sides do not have a nontrivial common divisor), but may still be the hypotenuse of a non-primitive triangle.
The nonhypotenuse numbers have been applied to prove the existence of addition chains that compute the first square numbers using only additions.
See also
Pythagorean theorem
Landau-Ramanujan constant
Fermat's theorem on sums of two squares |
https://en.wikipedia.org/wiki/Gluteal%20lines | The gluteal lines are three curved lines outlined from three bony ridges on the exterior surface of the ilium in the gluteal region. They are the anterior gluteal line; the inferior gluteal line, and the posterior gluteal line.
The gluteus minimus, medius, and maximus are muscles that arise from the gluteal lines.
Location
Anterior gluteal line
The anterior gluteal line is the middle curved gluteal line on the hip bone. It is the longest of the three gluteal lines, begins at the iliac crest, about 4 cm. behind its anterior extremity, and, taking a curved direction downward and backward, ends at the upper part of the greater sciatic notch.
The space between the anterior and posterior gluteal lines and the crest is concave, and gives origin to the gluteus medius muscle. Near the middle of this line a nutrient foramen is often seen.
Posterior gluteal line
Posterior gluteal line, also known as the superior curved line, the shortest of the three gluteal lines, begins at the iliac crest, about 5 cm in front of its posterior extremity; it is at first distinctly marked, but as it passes downward to the upper part of the greater sciatic notch, where it ends, it becomes less distinct, and is often altogether lost.
Behind this line is a narrow semilunar surface, the upper part of which is rough and gives origin to a portion of the gluteus maximus muscle. The lower part is smooth, and has no muscular fibers attached to it.
Inferior gluteal line
The inferior gluteal line, is the least distinct of the three gluteal lines, begins in front at the notch on the anterior border, and, curving backward and downward, ends near the middle of the greater sciatic notch.
Associated muscles
The gluteal muscles all arise from the gluteal lines. The gluteus minimus is a fan-shaped convergent muscle, arising from the outer surface of the ilium, between the anterior and inferior gluteal lines, and behind, from the margin of the greater sciatic notch.
The gluteus medius muscle originates |
https://en.wikipedia.org/wiki/IBM%20PS/55 | The or PS/55 is a personal computer series released from IBM Japan in 1987.
The PS/55 is the successor to IBM 5550 (Multistation 5550), but its architecture is based upon IBM PS/2. The first line-up of the series consisted of rebranded 5550 models except the Model 5570-S which was based on the PS/2 Model 80 (IBM 8580). Unlike the PS/2, most PS/2-based models have a 32-bit (80386 or 80486) CPU and Micro Channel (MCA) bus for the high-end business computing market. IBM Japan was hesitating to sell personal computers for consumers because the IBM JX failed. The AT bus model was released for home users in 1991.
Features
Display Adapter
The MCA video card called Display Adapter has a Japanese font containing nearly 7,000 glyphs stored in its ROM, which enables PS/2-based computers to display Japanese text without loading the font into memory. Similar to the IBM 5550, the display resolution in character mode is 1040×725 pixels (12×24 and 24×24 pixel Mincho font, 80×25 text) in 8 colors. The graphics mode is 1024×768 pixels in 16 colors. This is the same resolution as 8514/A and XGA/A, but not compatible.
The first Display Adapter was installed in the model 5570-S, also known as the first Micro Channel machine of PS/55. It had a compatibility problem with PS/2 applications. Since the model 5550-S released in 1988, the Display Adapter II that improved the PS/2 compatibility was introduced. In the boot sequence, the Display Adapter enables VGA on the motherboard, and it passes the video signal from the motherboard to adapter's VGA connector. When using Japanese DOS, VGA is disabled, and the Display Adapter switches its video selector from VGA to own video chip. In addition, it added the 256 color mode (1024×768 pixels in 256 colors chosen from 262,144 colors). The adapter has 1 MB of video RAM, and 256 KB of RAM for user-defined characters.
Most PS/2-based models have compatibility with the Display Adapter II. VGA and the following display modes are supported:
1040 |
https://en.wikipedia.org/wiki/Vertical%20tangent | In mathematics, particularly calculus, a vertical tangent is a tangent line that is vertical. Because a vertical line has infinite slope, a function whose graph has a vertical tangent is not differentiable at the point of tangency.
Limit definition
A function ƒ has a vertical tangent at x = a if the difference quotient used to define the derivative has infinite limit:
The first case corresponds to an upward-sloping vertical tangent, and the second case to a downward-sloping vertical tangent. The graph of ƒ has a vertical tangent at x = a if the derivative of ƒ at a is either positive or negative infinity.
For a continuous function, it is often possible to detect a vertical tangent by taking the limit of the derivative. If
then ƒ must have an upward-sloping vertical tangent at x = a. Similarly, if
then ƒ must have a downward-sloping vertical tangent at x = a. In these situations, the vertical tangent to ƒ appears as a vertical asymptote on the graph of the derivative.
Vertical cusps
Closely related to vertical tangents are vertical cusps. This occurs when the one-sided derivatives are both infinite, but one is positive and the other is negative. For example, if
then the graph of ƒ will have a vertical cusp that slopes up on the left side and down on the right side.
As with vertical tangents, vertical cusps can sometimes be detected for a continuous function by examining the limit of the derivative. For example, if
then the graph of ƒ will have a vertical cusp at x = a that slopes down on the left side and up on the right side.
Example
The function
has a vertical tangent at x = 0, since it is continuous and
Similarly, the function
has a vertical cusp at x = 0, since it is continuous,
and |
https://en.wikipedia.org/wiki/Perineal%20raphe | The perineal raphe is a visible line or ridge of tissue on the body that extends from the anus through the perineum to scrotum (male) or labia majora (female). It is found in both males and females, arises from the fusion of the urogenital folds, and is visible running medial through anteroposterior, to the anus where it resolves in a small knot of skin of varying size.
In males, this structure continues through the midline of the scrotum (scrotal raphe) and upwards through the posterior midline aspect of the penis (penile raphe). It also exists deeper through the scrotum where it is called the scrotal septum. It is the result of a fetal developmental phenomenon whereby the scrotum and penis close toward the midline and fuse.
See also
Embryonic and prenatal development of the male reproductive system in humans
Frenulum of prepuce of penis
Linea nigra
Raphe
Images |
https://en.wikipedia.org/wiki/Albert%20Cohen%20%28mathematician%29 | Albert Cohen (born 29 June 1965 in Paris) is a French mathematician, specializing in approximation theory, numerical analysis, and digital signal processing.
Biography
He is, through maternal descent, the grand-nephew of the physicist Jacques Solomon. From 1984 to 1987 Albert Cohen was a student at the École Polytechnique. In 1990 he defended his doctoral thesis at Paris Dauphine University. His thesis, written under the supervision of Yves Meyer, is entitled Ondelettes, analyse multi résolution et traitement numérique du signal (Wavelets, multiresolution analysis and digital signal analysis) From 1990 to 1991 Cohen was a postdoc at Bell Laboratories at Murray Hill. He completed his habilitation in 1992 at Paris Dauphine University. From 1993 to 1995 he worked at ENSTA Paris. Since 1995 he has been a professor at the Laboratoire Jacques-Louis Lions of Pierre and Marie Curie University (Paris 6), which is a component of Sorbonne University. He is the author of 3 books and the author of co-author of over 100 research articles.
Cohen developed in 1990, with Ingrid Daubechies and Jean-Christophe Feauveau, the first biorthogonal bases for wavelets; this research has an important application in the image compression standard JPEG-2000. With Wolfgang Dahmen and Ronald DeVore, Cohen then worked on the analysis of nonlinear and adaptive approximation methods, with a view to applications in learning theory and in numerical analysis of partial differential equations. He is interested in algorithmic problems involving a very large number of variables, which cause a prohibitive increase in the complexity of calculations. These problems arise in statistical learning theory, in the treatment of parametric and stochastic partial differential equations, and in the development of response surfaces from computer software involving adaptive numerical methods.
In 2000 Cohen received the grand prix Jacques Herbrand from the French Academy of Sciences. In 1995 he won the V. A. Popov Pr |
https://en.wikipedia.org/wiki/Mung%20bean%20sheets | Mung bean sheets are a type of Chinese noodle. It is transparent, flat, and sheet-like. They can be found, in dried form, in China and occasionally in some Chinatowns overseas.
Description
Similar to cellophane noodles, mung bean sheets are made of mung beans, except they are different in shape. The sheets are approximately 1 cm wide, like fettuccine noodles. They are produced in the Shandong province of eastern China (where cellophane noodles are also produced), as well as in the northern city of Tianjin, and have a springier, chewier texture than the thinner noodles.
Use in dishes
Mung bean sheets are used for cold dishes, hot pots, and stir fried dishes, in conjunction with sliced meats and/or seafood, vegetables, and seasonings. One such dish is Liang Fen, where the noodles are served cold with chili oil.
Chinese noodles
Shandong cuisine |
https://en.wikipedia.org/wiki/Web%20Cryptography%20API | The Web Cryptography API is the World Wide Web Consortium’s (W3C) recommendation for a low-level interface that would increase the security of web applications by allowing them to perform cryptographic functions without having to access raw keying material. This agnostic API would perform basic cryptographic operations, such as hashing, signature generation and verification and encryption as well as decryption from within a web application.
Description
On 26 January 2017, the W3C released its recommendation for a Web Cryptography API that could perform basic cryptographic operations in web applications. This agnostic API would utilize JavaScript to perform operations that would increase the security of data exchange within web applications. The API would provide a low-level interface to create and/or manage public keys and private keys for hashing, digital signature generation and verification and encryption and decryption for use with web applications.
The Web Cryptography API could be used for a wide range of uses, including:
Providing authentication for users and services
Electronic signing of documents or code
Protecting the integrity and confidentiality of communication and digital data exchange
Because the Web Cryptography API is agnostic in nature, it can be used on any platform. It would provide a common set of interfaces that would permit web applications and progressive web applications to conduct cryptographic functions without the need to access raw keying material. This would be done with the assistance of the SubtleCrypto interface, which defines a group of methods to perform the above cryptographic operations. Additional interfaces within the Web Cryptography API would allow for key generation, key derivation and key import and export.
Vision for using the Web Cryptography API
The W3C’s specification for the Web Cryptography API places focus on the common functionality and features that currently exist between platform-specific and standardize |
https://en.wikipedia.org/wiki/23%20%28number%29 | 23 (twenty-three) is the natural number following 22 and preceding 24.
In mathematics
Twenty-three is the ninth prime number, the smallest odd prime that is not a twin prime. It is, however, a cousin prime with 19, and a sexy prime with 17 and 29; while also being the largest member of the first prime sextuplet (7, 11, 13, 17, 19, 23). Twenty-three is also the fifth factorial prime, the second Woodall prime, and a happy number in decimal. It is an Eisenstein prime with no imaginary part and real part of the form It is also the fifth Sophie Germain prime and the fourth safe prime, and the next to last member of the first Cunningham chain of the first kind to have five terms (2, 5, 11, 23, 47). Since 14! + 1 is a multiple of 23, but 23 is not one more than a multiple of 14, 23 is the first Pillai prime. 23 is the smallest odd prime to be a highly cototient number, as the solution to for the integers 95, 119, 143, and 529. The third decimal repunit prime after R2 and R19 is R23, followed by R1031.
23 is the second Smarandache–Wellin prime in base ten, as it is the concatenation of the decimal representations of the first two primes (2 and 3) and is itself also prime.
The sum of the first nine primes up to 23 is a square: and the sum of the first 23 primes is 874, which is divisible by 23, a property shared by few other numbers.
In the list of fortunate numbers, 23 occurs twice, since adding 23 to either the fifth or eighth primorial gives a prime number (namely 2333 and 9699713).
23 has the distinction of being one of two integers that cannot be expressed as the sum of fewer than 9 cubes of positive integers (the other is 239). See Waring's problem.
The twenty-third highly composite number 20,160 is one less than the last number (the 339th super-prime 20,161) that cannot be expressed as the sum of two abundant numbers.
23 is the number of trees on 8 unlabeled nodes. It is also a Wedderburn–Etherington number, which are numbers that can be used to count |
https://en.wikipedia.org/wiki/Sleep%20medicine | Sleep medicine is a medical specialty or subspecialty devoted to the diagnosis and therapy of sleep disturbances and disorders. From the middle of the 20th century, research has provided increasing knowledge of, and answered many questions about, sleep–wake functioning. The rapidly evolving field has become a recognized medical subspecialty in some countries. Dental sleep medicine also qualifies for board certification in some countries. Properly organized, minimum 12-month, postgraduate training programs are still being defined in the United States. In some countries, the sleep researchers and the physicians who treat patients may be the same people.
The first sleep clinics in the United States were established in the 1970s by interested physicians and technicians; the study, diagnosis and treatment of obstructive sleep apnea were their first tasks. As late as 1999, virtually any American physician, with no specific training in sleep medicine, could open a sleep laboratory.
Disorders and disturbances of sleep are widespread and can have significant consequences for affected individuals as well as economic and other consequences for society. The US National Transportation Safety Board has, according to Charles Czeisler, member of the Institute of Medicine and Director of the Harvard University Medical School Division of Sleep Medicine at Brigham and Women's Hospital, discovered that the leading cause (31%) of fatal-to-the-driver heavy truck crashes is fatigue related (though rarely associated directly with sleep disorders, such as sleep apnea), with drugs and alcohol as the number two cause (29%). Sleep deprivation has also been a significant factor in dramatic accidents, such as the Exxon Valdez oil spill, the nuclear incidents at Chernobyl and Three Mile Island and the explosion of the space shuttle Challenger.
Scope and classification
Competence in sleep medicine requires an understanding of a plethora of very diverse disorders, many of which present with si |
https://en.wikipedia.org/wiki/Desulfovibrio%20marrakechensis | Desulfovibrio marrakechensis is a bacterium. It is sulfate-reducing and tyrosol-oxidising. Its cells are mesophilic, non-spore-forming, non-motile, Gram-negative, catalase-positive and straight-rod-shaped. They contain cytochrome c(3) and desulfoviridin. The type strain is EMSSDQ(4)(T) (=DSM 19337(T) =ATCC BAA-1562(T)). |
https://en.wikipedia.org/wiki/Visual%20Basic%20%28classic%29 | The original Visual Basic (also referred to as Classic Visual Basic) is a third-generation event-driven programming language from Microsoft known for its Component Object Model (COM) programming model first released in 1991 and declared legacy during 2008. Microsoft intended Visual Basic to be relatively easy to learn and use. Visual Basic was derived from BASIC and enables the rapid application development (RAD) of graphical user interface (GUI) applications, access to databases using Data Access Objects, Remote Data Objects, or ActiveX Data Objects, and creation of ActiveX controls and objects.
A programmer can create an application using the components provided by the Visual Basic program itself. Over time the community of programmers developed third-party components. Programs written in Visual Basic can also make use of the Windows API, which requires external functions declarations.
The final release was version 6 in 1998. On April 8, 2008, Microsoft stopped supporting Visual Basic 6.0 IDE. The Microsoft Visual Basic team still maintains compatibility for Visual Basic 6.0 applications through its "It Just Works" program on supported Windows operating systems.
In 2014, some software developers still preferred Visual Basic 6.0 over its successor, Visual Basic .NET. Visual Basic 6.0 was selected as the most dreaded programming language by respondents of Stack Overflow's annual developer survey in 2016, 2017, and 2018.
A dialect of Visual Basic, Visual Basic for Applications (VBA), is used as a macro or scripting language within several Microsoft and ISV applications, including Microsoft Office.
Language features
Like the BASIC programming language, Visual Basic was designed to have an easy learning curve. Programmers can create both simple and complex GUI applications.
Programming in VB is a combination of visually arranging components or controls on a form, specifying attributes and actions for those components, and writing additional lines of code for mor |
https://en.wikipedia.org/wiki/Wagner%27s%20gene%20network%20model | Wagner's gene network model is a computational model of artificial gene networks, which explicitly modeled the developmental and evolutionary process of genetic regulatory networks. A population with multiple organisms can be created and evolved from generation to generation. It was first developed by Andreas Wagner in 1996 and has been investigated by other groups to study the evolution of gene networks, gene expression, robustness, plasticity and epistasis.
Assumptions
The model and its variants have a number of simplifying assumptions. Three of them are listing below.
The organisms are modeled as gene regulatory networks. The models assume that gene expression is regulated exclusively at the transcriptional level;
The product of a gene can regulate the expression of (be a regulator of) that source gene or other genes. The models assume that a gene can only produce one active transcriptional regulator;
The effects of one regulator are independent of effects of other regulators on the same target gene.
Genotype
The model represents individuals as networks of interacting transcriptional regulators. Each individual expresses genes encoding transcription factors. The product of each gene can regulate the expression level of itself and/or the other genes through cis-regulatory elements. The interactions among genes constitute a gene network that is represented by a × regulatory matrix in the model. The elements in matrix R represent the interaction strength. Positive values within the matrix represent the activation of the target gene, while negative ones represent repression. Matrix elements with value 0 indicate the absence of interactions between two genes.
Phenotype
The phenotype of each individual is modeled as the gene expression pattern at time . It is represented by a state vector in this model.
whose element denotes the expression state of gene i at time t. In the original Wagner model,
∈
where 1 represents the gene is expressed whil |
https://en.wikipedia.org/wiki/No%20Man%27s%20Sky | No Man's Sky is an action-adventure survival game developed and published by Hello Games. It was released worldwide for the PlayStation 4 and Windows in August 2016, for Xbox One in July 2018, for the PlayStation 5 and Xbox Series X and Series S consoles in November 2020, for Nintendo Switch in October 2022, and for macOS in June 2023. The game is built around five pillars: exploration, survival, combat, trading and base building. Players can engage with the entirety of a procedurally generated deterministic open world universe, which includes over 18 quintillion planets. Through the game's procedural generation system, planets have their own ecosystems with unique forms of flora and fauna, and various alien species may engage the player in combat or trade within planetary systems. Players advance in the game by mining for resources to power and improve their equipment, buying and selling resources using credits earned by documenting flora and fauna or trading with the aforementioned lifeforms, building planetary bases and expanding space fleets, or otherwise following the game's overarching plot by seeking out the mystery around the entity known as The Atlas.
Sean Murray, the founder of Hello Games, wanted to create a game that captured the sense of exploration and optimism of science fiction writings and art of the 1970s and 1980s. The game was developed over three years by a small team at Hello Games with promotional and publishing help from Sony Interactive Entertainment. The gaming media saw this as an ambitious project for a small team, and Murray and Hello Games drew significant attention leading to its release.
No Man's Sky received mixed reviews at its 2016 launch, with some critics praising the technical achievements of the procedurally generated universe, while others considered the gameplay lackluster and repetitive. However, the critical response was marred by the lack of several features that had been reported to be in the game, particularly multipla |
https://en.wikipedia.org/wiki/MT-ND5 | MT-ND5 is a gene of the mitochondrial genome coding for the NADH-ubiquinone oxidoreductase chain 5 protein (ND5). The ND5 protein is a subunit of NADH dehydrogenase (ubiquinone), which is located in the mitochondrial inner membrane and is the largest of the five complexes of the electron transport chain. Variations in human MT-ND5 are associated with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) as well as some symptoms of Leigh's syndrome and Leber's hereditary optic neuropathy (LHON).
Structure
MT-ND5 is located in mitochondrial DNA from base pair 12,337 to 14,148. The MT-ND5 gene produces a 67 kDa protein composed of 603 amino acids. MT-ND5 is one of seven mitochondrial genes encoding subunits of the enzyme NADH dehydrogenase (ubiquinone), together with MT-ND1, MT-ND2, MT-ND3, MT-ND4, MT-ND4L, and MT-ND6. Also known as Complex I, this enzyme is the largest of the respiratory complexes. The structure is L-shaped with a long, hydrophobic transmembrane domain and a hydrophilic domain for the peripheral arm that includes all the known redox centres and the NADH binding site. MT-ND5 and the rest of the mitochondrially encoded subunits are the most hydrophobic of the subunits of Complex I and form the core of the transmembrane region.
Function
The MT-ND5 product is a subunit of the respiratory chain Complex I that is supposed to belong to the minimal assembly of core proteins required to catalyze NADH dehydrogenation and electron transfer to ubiquinone (coenzyme Q10). Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2. The electrons are transferred through a series of iron-sulfur (Fe-S) clusters in the prosthetic arm and finally to coenzyme Q10 (CoQ), which is reduced to ubiquinol (CoQH2). The flow of electrons changes the redox state of the protein, resulting in a conformational change and pK shift of the ionizable side chain, |
https://en.wikipedia.org/wiki/The%20Cancer%20Imaging%20Archive | The Cancer Imaging Archive (TCIA) is an open-access database of medical images for cancer research. The site is funded by the National Cancer Institute's (NCI) Cancer Imaging Program, and the contract is operated by the University of Arkansas for Medical Sciences. Data within the archive is organized into collections which typically share a common cancer type and/or anatomical site. The majority of the data consists of CT, MRI, and nuclear medicine (e.g. PET) images stored in DICOM format, but many other types of supporting data are also provided or linked to, in order to enhance research utility. All data are de-identified in order to comply with the Health Insurance Portability and Accountability Act and National Institutes of Health data sharing policies.
TCIA resources are intended to support:
Development of computer aided diagnosis methods (quantitative imaging)
Evaluation of unbiased science reproducibility by acceptable standard statistical methods
Research on correlation of clinical diagnostic medical images with digital microscopic histological images
Exploratory biomarker research for which imaging is a key element
Collaboration between cross-disciplinary investigators where imaging is crucial to research on tumor heterogeneity, between patients and within the tumor; tissue temporal response tracking - objective measurements of tumor progression; imaging genomics and Big Data linkages and analysis (clinical, histo-pathology, genomics)
TCIA is recognized as a recommended repository for the Scientific Data, PLOS One, and F1000Research journals. It is also listed in the Registry of Research Data Repositories.
History
Prior to the creation of TCIA, the NCI funded development of the National Biomedical Imaging Archive. NBIA is an open-source Web application which was designed to allow the storage and query of DICOM images. TCIA was subsequently initiated in December 2010 to expand data sharing activities by funding a service component which would h |
https://en.wikipedia.org/wiki/Geographic%20number | A geographic number is a telephone number, from a range of numbers in the United Kingdom National Telephone Numbering Plan, where part of its digit structure contains geographic significance used for routing calls to the physical location of the network termination point of the subscriber to whom the telephone number has been assigned, or where the network termination point does not relate to the geographic area code but where the tariffing remains consistent with that geographic area code.
In the Netherlands any telephone number consists of 10 digits and the geographic number is often separated with a minus sign. The number 0592 for example is the geographic number for the area in and around the city Assen, and Groningen uses 050. Someone living in Assen has a caller ID of 6 numbers and someone in Groningen has a caller ID of 7 numbers.
See also
Telephone number
Telephone numbering plan
List of country calling codes
Caller id
Telephone numbers
Identifiers |
https://en.wikipedia.org/wiki/Weak%20localization | Weak localization is a physical effect which occurs in disordered electronic systems at very low temperatures. The effect manifests itself as a positive correction to the resistivity of a metal or semiconductor. The name emphasizes the fact that weak localization is a precursor of Anderson localization, which occurs at strong disorder.
General principle
The effect is quantum-mechanical in nature and has the following origin: In a disordered electronic system, the electron motion is diffusive rather than ballistic. That is, an electron does not move along a straight line, but experiences a series of random scatterings off impurities which results in a random walk.
The resistivity of the system is related to the probability of an electron to propagate between two given points in space. Classical physics assumes that the total probability is just the sum of the probabilities of the paths connecting the two points. However quantum mechanics tells us that to find the total probability we have to sum up the quantum-mechanical amplitudes of the paths rather than the probabilities themselves. Therefore, the correct (quantum-mechanical) formula for the probability for an electron to move from a point A to a point B includes the classical part (individual probabilities of diffusive paths) and a number of interference terms (products of the amplitudes corresponding to different paths). These interference terms effectively make it more likely that a carrier will "wander around in a circle" than it would otherwise, which leads to an increase in the net resistivity. The usual formula for the conductivity of a metal (the so-called Drude formula) corresponds to the former classical terms, while the weak localization correction corresponds to the latter quantum interference terms averaged over disorder realizations.
The weak localization correction can be shown to come mostly from quantum interference between self-crossing paths in which an electron can propagate in the clock-wi |
https://en.wikipedia.org/wiki/Emergency%20power%20system | An emergency power system is an independent source of electrical power that supports important electrical systems on loss of normal power supply. A standby power system may include a standby generator, batteries and other apparatus. Emergency power systems are installed to protect life and property from the consequences of loss of primary electric power supply. It is a type of continual power system.
They find uses in a wide variety of settings from homes to hospitals, scientific laboratories, data centers, telecommunication equipment and ships. Emergency power systems can rely on generators, deep-cycle batteries, flywheel energy storage or fuel cells.
History
Emergency power systems were used as early as World War II on naval ships. In combat, a ship may lose the function of its boilers, which power the steam turbines for the ship's generator. In such a case, one or more diesel engines are used to drive back-up generators. Early transfer switches relied on manual operation; two switches would be placed horizontally, in line and the "on" position facing each other. a rod is placed in between. In order to operate the switch one source must be turned off, the rod moved to the other side and the other source turned on.
Operation in buildings
Mains power can be lost due to downed lines, malfunctions at a sub-station, inclement weather, planned blackouts or in extreme cases a grid-wide failure. In modern buildings, most emergency power systems have been and are still based on generators. Usually, these generators are Diesel engine driven, although smaller buildings may use a gasoline engine driven generator.
Some larger building have gas turbines, but they can take 5 or up to 30 minutes to produce power.
Lately, more use is being made of deep cycle batteries and other technologies such as flywheel energy storage or fuel cells. These latter systems do not produce polluting gases, thereby allowing the placement to be done within the building. Also, as a second advan |
https://en.wikipedia.org/wiki/Stepper%20motor | A stepper motor, also known as step motor or stepping motor, is an electrical motor that rotates in a series of small angular steps, instead of continuously. Stepper motors are a type of digital actuators. Stepper motors are an eletromagnetic actuator; it converts electromagnetic energy into mechanical energy to perform mechanical work.
A stepper motor is a brushless DC electric motor that divides a full rotation into a number of equal steps. The motor's position can be commanded to move and hold at one of these steps without any position sensor for feedback (an open-loop controller), as long as the motor is correctly sized to the application in respect to torque and speed.
Switched reluctance motors are very large stepping motors with a reduced pole count, and generally are closed-loop commutated.
Mechanism
Brushed DC motors rotate continuously when DC voltage is applied to their terminals. The stepper motor is known for its property of converting a train of input pulses (typically square waves) into a precisely defined increment in the shaft’s rotational position. Each pulse rotates the shaft through a fixed angle.
Stepper motors effectively have multiple "toothed" electromagnets arranged as a stator around a central rotor, a gear-shaped piece of iron. The electromagnets are energized by an external driver circuit or a micro controller. To make the motor shaft turn, first, one electromagnet is given power, which magnetically attracts the gear's teeth. When the gear's teeth are aligned to the first electromagnet, they are slightly offset from the next electromagnet. This means that when the next electromagnet is turned on and the first is turned off, the gear rotates slightly to align with the next one. From there the process is repeated. Each of the partial rotations is called a "step", with an integer number of steps making a full rotation. In that way, the motor can be turned by a precise angle.
The circular arrangement of electromagnets is divided into gr |
https://en.wikipedia.org/wiki/Guano | Guano (Spanish from ) is the accumulated excrement of seabirds or bats. Guano is a highly effective fertilizer due to the high content of nitrogen, phosphate, and potassium, all key nutrients essential for plant growth. Guano was also, to a lesser extent, sought for the production of gunpowder and other explosive materials.
The 19th-century seabird guano trade played a pivotal role in the development of modern input-intensive farming. The demand for guano spurred the human colonization of remote bird islands in many parts of the world.
Unsustainable seabird guano mining processes can result in permanent habitat destruction and the loss of millions of seabirds.
Bat guano is found in caves throughout the world. Many cave ecosystems are wholly dependent on bats to provide nutrients via their guano which supports bacteria, fungi, invertebrates, and vertebrates. The loss of bats from a cave can result in the extinction of species that rely on their guano. Unsustainable harvesting of bat guano may cause bats to abandon their roost.
Demand for guano rapidly declined after 1910 with the development of the Haber–Bosch process for extracting nitrogen from the atmosphere.
Composition and properties
Seabird guano
Seabird guano is the fecal excrement from marine birds and has an organic matter content greater than 40%, is a source of nitrogen (N) and available phosphate (P2O5).
Seabird guano contains plant nutrients including nitrogen, phosphorus, calcium and potassium.
Bat guano
Bat guano is partially decomposed bat excrement and has an organic matter content greater than 40%, is a source of nitrogen, and may contain up to 6% available phosphate (P2O5). The feces of insectivorous bats consists of fine particles of insect exoskeleton, which are largely composed of chitin. Elements found in large concentrations include nitrogen, phosphorus, potassium and trace elements needed for plant growth. Bat guano is slightly alkaline with an average pH of 7.25.
Chitin from i |
https://en.wikipedia.org/wiki/Sandi%20Klav%C5%BEar | Sandi Klavžar (born 5 February 1962) is a Slovenian mathematician working in the area of graph theory and its applications. He is a professor of mathematics at the University of Ljubljana.
Education
Klavžar received his Ph.D. from the University of Ljubljana in 1990, under the supervision of Wilfried Imrich and Tomaž Pisanski.
Research
Klavžar's research concerns graph products, metric graph theory, chemical graph theory, graph domination, and the Tower of Hanoi. Together with Wilfried Imrich and Richard Hammack, he is the author of the book Handbook of Product Graphs (CRC Press, 2011). Together with Andreas M. Hinz, Uroš Milutinović, and Ciril Petr, he is the author of the book The Tower of Hanoi – Myths and Maths (Springer, Basel, 2013).
Awards and honors
In 2007, Klavžar received the Zois award for exceptional contributions to science and mathematics. |
https://en.wikipedia.org/wiki/Bilinear%20program | In mathematics, a bilinear program is a nonlinear optimization problem whose objective or constraint functions are bilinear. An example is the pooling problem. |
https://en.wikipedia.org/wiki/HackerNest | HackerNest is a not-for-profit organization and global movement founded on January 11, 2011. The organization unites local technology communities around the world through community events and socially beneficial hackathons to further its mission of economic development through technological proliferation. It is Canada's largest, most prolific technology community with growing international reach.
Background
HackerNest was founded on the belief that the fastest, most permanent way to improve the world is to build supportive local technology and innovation communities characterized by trust, sharing, and respect. The rationale is that the technology community is the cornerstone of economic development enabling collaboration, innovation, knowledge-sharing, recruiting, and scientific progress. Growing and strengthening the community lets businesses hire better, perform better, and create more jobs, which ultimately increases economic prosperity.
The organization's ideology is rooted in the idea that minor tweaks at the start of a process in a dynamic system can have a major impact on the end result. . HackerNest "splinter cells" (chapters) regularly host "Tech Socials" open to anyone interested in technology. The events vary slightly by city, but maintain the same core tenets: all are friendly and down-to-earth.
The first Tech Social was held in Toronto on Monday, January 31, 2011. HackerNest Toronto is currently the world's largest Meetup group for programmers and Canada's largest technologist community.
As of July 2017, HackerNest splinter cells have run over 550+ events in 34 cities across 14 countries on 5 continents.
Activities
In 2014, HackerNest produced Construct, Canada's largest hardware hackathon and DementiaHack for the British government, the world's first hackathon dedicated to helping people with dementia and their caregivers.
In 2015, the organization produced Deloitte's first internal innovation hackathon as well as DementiaHack Facebook as |
https://en.wikipedia.org/wiki/CTU2 | CTU2 (formerly known as C16orf84) is a human gene located on chromosome 16. The mRNA encodes the longer isoform. The gene encodes a cytoplasmic protein that plays a probable role in tRNA modification. |
https://en.wikipedia.org/wiki/Indra%27s%20Pearls%20%28book%29 | Indra's Pearls: The Vision of Felix Klein is a geometry book written by David Mumford, Caroline Series and David Wright, and published by Cambridge University Press in 2002 and 2015.
The book explores the patterns created by iterating conformal maps of the complex plane called Möbius transformations, and their connections with symmetry and self-similarity. These patterns were glimpsed by German mathematician Felix Klein, but modern computer graphics allows them to be fully visualised and explored in detail.
Title
The book's title refers to Indra's net, a metaphorical object described in the Buddhist text of the Flower Garland Sutra. Indra's net consists of an infinite array of gossamer strands and pearls. The frontispiece to Indra's Pearls quotes the following description:
In the glistening surface of each pearl are reflected all the other pearls ... In each reflection, again are reflected all the infinitely many other pearls, so that by this process, reflections of reflections continue without end.
The allusion to Felix Klein's "vision" is a reference to Klein's early investigations of Schottky groups and hand-drawn plots of their limit sets. It also refers to Klein's wider vision of the connections between group theory, symmetry and geometry - see Erlangen program.
Contents
The contents of Indra's Pearls are as follows:
Chapter 1. The language of symmetry – an introduction to the mathematical concept of symmetry and its relation to geometric groups.
Chapter 2. A delightful fiction – an introduction to complex numbers and mappings of the complex plane and the Riemann sphere.
Chapter 3. Double spirals and Möbius maps – Möbius transformations and their classification.
Chapter 4. The Schottky dance – pairs of Möbius maps which generate Schottky groups; plotting their limit sets using breadth-first searches.
Chapter 5. Fractal dust and infinite words – Schottky limit sets regarded as fractals; computer generation of these fractals using depth-first searches and i |
https://en.wikipedia.org/wiki/Kalman%20filter | For statistics and control theory, Kalman filtering, also known as linear quadratic estimation (LQE), is an algorithm that uses a series of measurements observed over time, including statistical noise and other inaccuracies, and produces estimates of unknown variables that tend to be more accurate than those based on a single measurement alone, by estimating a joint probability distribution over the variables for each timeframe. The filter is named after Rudolf E. Kálmán, who was one of the primary developers of its theory.
This digital filter is sometimes termed the Stratonovich–Kalman–Bucy filter because it is a special case of a more general, nonlinear filter developed somewhat earlier by the Soviet mathematician Ruslan Stratonovich. In fact, some of the special case linear filter's equations appeared in papers by Stratonovich that were published before summer 1961, when Kalman met with Stratonovich during a conference in Moscow.
Kalman filtering has numerous technological applications. A common application is for guidance, navigation, and control of vehicles, particularly aircraft, spacecraft and ships positioned dynamically. Furthermore, Kalman filtering is a concept much applied in time series analysis used for topics such as signal processing and econometrics. Kalman filtering is also one of the main topics of robotic motion planning and control and can be used for trajectory optimization. Kalman filtering also works for modeling the central nervous system's control of movement. Due to the time delay between issuing motor commands and receiving sensory feedback, the use of Kalman filters provides a realistic model for making estimates of the current state of a motor system and issuing updated commands.
The algorithm works by a two-phase process. For the prediction phase, the Kalman filter produces estimates of the current state variables, along with their uncertainties. Once the outcome of the next measurement (necessarily corrupted with some error, inclu |
https://en.wikipedia.org/wiki/Join%20selection%20factor | Within computing, author O'Connell defines join selection factor as "[t]he percentage (or fraction) of records in one file that will be joined with records of another file". This can be calculated when two database tables are to be joined. It is primarily concerned with query optimization. |
https://en.wikipedia.org/wiki/Dipankar%20Das%20Sarma | Dipankar Das Sarma, popularly known as D.D. Sarma, is an Indian scientist and structural chemist, known for his researches in the fields of Solid State Chemistry, Spectroscopy, Condensed Matter Physics, Materials Science, and Nanoscience. He is a former MLS Chair Professor of Physics and Chairman of the Centre for Advanced Materials and the GAST Professor of Uppsala University, Sweden, A recipient of TWAS Physics Prize and the UNESCO Biennial Javed Husain Prize, Sarma was honored by the Council for Scientific and Industrial Research (CSIR), Government of India, in 1994, with the Shanti Swarup Bhatnagar Prize for Science and Technology.
Biography
Dipankar Das Sarma was born on 15 September 1955 in Kolkata, in West Bengal. He did a five-year integrated masters course in Physics from the Indian Institute of Technology, Kanpur in 1977 and enrolled for research at the Indian Institute of Science, (IISc) Bengaluru from where he secured his PhD in 1982 under the tutelage of renowned solid state chemist, C. N. R. Rao. He worked as a research associate at IISc for one year (1982–83), moved to Forschungszentrum Jülich, (Jülich Research Centre) Germany as a guest scientist in 1984 and returned to IISc as a lecturer in 1986. He stayed at IISc where he became the assistant professor in 1989, associate professor in 1993 and a professor in 1999. He remains a professor at Solid State and Structural Chemistry Unit at the institution. He also served as a visiting professor at the University of Tokyo (2001–02) and at the Istituto di Struttura della Materia, CNR at their Rome and Trieste centres in 2002.
Positions
Prof. Sarma holds a number of academic positions in India and abroad. Presently, he is J.N. Tata Chair Professor at the Solid State and Structural Chemistry Unit of the Indian Institute of Science. Besides heading the Solid State and Structural Chemistry Unit, he served as a guest professor at the Uppsala University, Sweden, a Distinguished Scientist at the CSIR-Network |
https://en.wikipedia.org/wiki/Value%20function | The value function of an optimization problem gives the value attained by the objective function at a solution, while only depending on the parameters of the problem. In a controlled dynamical system, the value function represents the optimal payoff of the system over the interval [t, t1] when started at the time-t state variable x(t)=x. If the objective function represents some cost that is to be minimized, the value function can be interpreted as the cost to finish the optimal program, and is thus referred to as "cost-to-go function." In an economic context, where the objective function usually represents utility, the value function is conceptually equivalent to the indirect utility function.
In a problem of optimal control, the value function is defined as the supremum of the objective function taken over the set of admissible controls. Given , a typical optimal control problem is to
subject to
with initial state variable . The objective function is to be maximized over all admissible controls , where is a Lebesgue measurable function from to some prescribed arbitrary set in . The value function is then defined as
with , where is the "scrap value". If the optimal pair of control and state trajectories is , then . The function that gives the optimal control based on the current state is called a feedback control policy, or simply a policy function.
Bellman's principle of optimality roughly states that any optimal policy at time , taking the current state as "new" initial condition must be optimal for the remaining problem. If the value function happens to be continuously differentiable, this gives rise to an important partial differential equation known as Hamilton–Jacobi–Bellman equation,
where the maximand on the right-hand side can also be re-written as the Hamiltonian, , as
with playing the role of the costate variables. Given this definition, we further have , and after differentiating both sides of the HJB equation with respect to ,
which |
https://en.wikipedia.org/wiki/Alberto%20Vecchio | Alberto Vecchio () is a physicist, professor at University of Birmingham in the School of Physics and Astronomy, and the Director of the Institute of Gravitational Wave Astronomy. He was a contributor in the upgrade of LIGO to Advanced LIGO which resulted in the discovery of gravitational waves in February 2016.
Education
He graduated with a degree in theoretical physics as an undergraduate (Laurea) at Ghislieri College and the University of Pavia, he then obtained a PhD in astronomy from the University of Milan in 1996, where he worked with Bruno Bertotti, one of Erwin Schrödinger's last students.
LIGO
Working in collaboration with other scientists at University of Birmingham, he helped build and test instruments to detect gravitational waves. After these were improved further as part of the Advanced LIGO upgrade, gravitational waves were detected. These instruments allowed the properties of the sources from the gravitational wave signatures to be extracted. |
https://en.wikipedia.org/wiki/Microcirculatory%20Society | The Microcirculatory Society, Inc. was the first scientific society founded to promote research and teaching in the field of microcirculation. Although many members come from all over the world, most of its membership comes from the United States and Canada. Other societies have subsequently been formed to represent specific global regions, including the European Society for Microcirculation, the Asian Union for Microcirculation and the Australia & New Zealand Microcirculation Society, as well as individual countries, such as Britain, Japan, Germany, France, Hungary, Israel, Italy, China, the Netherlands, Switzerland, and others. The Microcirculatory Society publishes the scientific journal Microcirculation in conjunction with the British Microcirculation Society.
History
The society was founded in 1953. Its first president was Edward H Bloch.
Society Presidents have been:
2011-2012: Boegehold, Matthew A.
2010-2011: Zawieja, David C.
2009-2010: Jackson, William F.
2008-2009: Segal, Steven S.
2007-2008: Meininger, Cynthia
2006-2007: Secomb, Timothy W.
2005-2006: Hester, Robert L.
2004-2005: Bohlen, H. Glenn
2003-2004: Schmid-Schönbein, Geert
2002-2003: McDonagh, Paul F.
2001-2002: Sarelius, Ingrid H.
2000-2001: Durán, Walter
1999-2000: Tuma, Ronald F.
1998-1999: Klitzman, Bruce
1997-1998: Lombard, Julian H.
1996-1997: Huxley, Virginia H.
1995-1996: Meininger, Gerald A.
1994-1995: Curry, Fitz-Roy E.
1993-1994: Pittman, Roland N.
1992-1993: Lipowsky, Herbert H.
1991-1992: Granger, D. Neil
1990-1991: Bassingthwaighte, James B.
1989-1990: Granger, Harris J.
1988-1989: Gore, Robert W.
1987-1988: Joyner, William L.
1986-1987: Harris, Patrick D.
1985-1986: Intaglietta, Marcos
1984-1985: Duling, Brian R.
1983-1984: Groom, Alan C.
1982-1983: Taylor, Aubrey E.
NOTE: Mary P. Wiedeman died before taking
office and Dr. Taylor continued as President
1981-1982: Taylor, Aubrey E.
1980-1981: Chien, Shu
1979-1980: Zweifach, Benjamin W.
1978-1979: Staub, Norman C.
1977-1978: Diana, |
https://en.wikipedia.org/wiki/List%20of%20symbols%20of%20states%20and%20territories%20of%20Australia | This is a list of the symbols of the states and territories of Australia. Each state and territory has a unique set of official symbols, as well as the national symbols of Australia.
States
Territories
See also
Australian state colours
National colours of Australia
National symbols of Australia
List of Australian bird emblems
List of Australian mammal emblems
States and territories of Australia
Notes |
https://en.wikipedia.org/wiki/Nehalem%20%28microarchitecture%29 | Nehalem is the codename for Intel's 45 nm microarchitecture released in November 2008. It was used in the first-generation of the Intel Core i5 and i7 processors, and succeeds the older Core microarchitecture used on Core 2 processors. The term "Nehalem" comes from the Nehalem River.
Nehalem is built on the 45 nm process, is able to run at higher clock speeds, and is more energy-efficient than Penryn microprocessors. Hyper-threading is reintroduced, along with a reduction in L2 cache size, as well as an enlarged L3 cache that is shared among all cores. Nehalem is an architecture that differs radically from NetBurst, while retaining some of the latter's minor features.
Nehalem later received a die-shrink to 32 nm with Westmere, and was fully succeeded by "second-generation" Sandy Bridge in January 2011.
Technology
Cache line block on L2/L3 cache was reduced from 128 bytes in NetBurst & Conroe/Penryn to 64 bytes per line in this generation (same size as Yonah and Pentium M).
Hyper-threading reintroduced.
Intel Turbo Boost 1.0.
2–24 MiB L3 cache
Instruction Fetch Unit (IFU) containing second-level branch predictor with two level Branch Target Buffer (BTB) and Return Stack Buffer (RSB). Nehalem also supports all predictor types previously used in Intel's processors like Indirect Predictor and Loop Detector.
sTLB (second level unified translation lookaside buffer) (i.e. both instructions and data) that contains 512 entries for small pages only, and is again 4 way associative.
3 integer ALU, 2 vector ALU and 2 AGU per core.
Native (all processor cores on a single die) quad- and octa-core processors
Intel QuickPath Interconnect in high-end models replacing the legacy front side bus
64 KB L1 cache per core (32 KB L1 data and 32 KB L1 instruction), and 256 KB L2 cache per core.
Integration of PCI Express and DMI into the processor in mid-range models, replacing the northbridge
Integrated memory controller supporting two or three memory channels of DDR3 SDRAM |
https://en.wikipedia.org/wiki/Standard%20probability%20space | In probability theory, a standard probability space, also called Lebesgue–Rokhlin probability space or just Lebesgue space (the latter term is ambiguous) is a probability space satisfying certain assumptions introduced by Vladimir Rokhlin in 1940. Informally, it is a probability space consisting of an interval and/or a finite or countable number of atoms.
The theory of standard probability spaces was started by von Neumann in 1932 and shaped by Vladimir Rokhlin in 1940. Rokhlin showed that the unit interval endowed with the Lebesgue measure has important advantages over general probability spaces, yet can be effectively substituted for many of these in probability theory. The dimension of the unit interval is not an obstacle, as was clear already to Norbert Wiener. He constructed the Wiener process (also called Brownian motion) in the form of a measurable map from the unit interval to the space of continuous functions.
Short history
The theory of standard probability spaces was started by von Neumann in 1932 and shaped by Vladimir Rokhlin in 1940. For modernized presentations see , , and .
Nowadays standard probability spaces may be (and often are) treated in the framework of descriptive set theory, via standard Borel spaces, see for example . This approach is based on the isomorphism theorem for standard Borel spaces . An alternate approach of Rokhlin, based on measure theory, neglects null sets, in contrast to descriptive set theory.
Standard probability spaces are used routinely in ergodic theory.
Definition
One of several well-known equivalent definitions of the standardness is given below, after some preparations. All probability spaces are assumed to be complete.
Isomorphism
An isomorphism between two probability spaces , is an invertible map such that and both are (measurable and) measure preserving maps.
Two probability spaces are isomorphic if there exists an isomorphism between them.
Isomorphism modulo zero
Two probability spaces , are iso |
https://en.wikipedia.org/wiki/Infinitesimal%20model | The infinitesimal model, also known as the polygenic model, is a widely used statistical model in quantitative genetics and in genome-wide association studies. Originally developed in 1918 by Ronald Fisher, it is based on the idea that variation in a quantitative trait is influenced by an infinitely large number of genes, each of which makes an infinitely small (infinitesimal) contribution to the phenotype, as well as by environmental factors. In "The Correlation between Relatives on the Supposition of Mendelian Inheritance", the original 1918 paper introducing the model, Fisher showed that if a trait is polygenic, "then the random sampling of alleles at each gene produces a continuous, normally distributed phenotype in the population". However, the model does not necessarily imply that the trait must be normally distributed, only that its genetic component will be so around the average of that of the individual's parents. The model served to reconcile Mendelian genetics with the continuous distribution of quantitative traits documented by Francis Galton.
The model allows genetic variance to be assumed to remain constant even when natural selection is occurring, because each locus makes an infinitesimal contribution to the variance. Consequently, all decline in genetic variance is assumed to be due to genetic drift. It also relies on the fact that there must be a large enough number of loci for the distribution of loci to be normal, an assumption which breaks down if a trait is influenced by a small number of loci. According to one research group, the model "…is obviously not an exact representation of the genome of any species," as humans do not have an infinite number of genes, "but is a useful assumption to make in genetic evaluation," such as "explaining the underlying variation of a trait." Some phenotypes undergo evolutionary adaptation such that they involve a modest number of loci of large effect. Complex traits, however, have been shown to be largely expl |
https://en.wikipedia.org/wiki/Isabelle%20Galmiche | Isabelle Galmiche (Gal-MEE-sh; born 19 November 1971) is a French rally co-driver and mathematics teacher. As of January 2022, she is the co-driver for nine-time World Rally Champion Sebastien Loeb, driving for M-Sport Ford in the World Rally Championship.
Rally career
Galmiche and Loeb won the 90th Rally Monte Carlo on January 23, 2022, becoming the oldest driver and female co-driver, respectively, to win a WRC rally. Galmiche became the first woman co-driver to win a WRC event since Fabrizia Pons in 1997. She has been Loeb's co-driver on tests, deputising for his former co-driver Daniel Elena on a part-time basis, since 2012.
Rally victories
WRC victories
World Rally Championship results |
https://en.wikipedia.org/wiki/Native%20American%20mascot%20laws%20and%20regulations | The use of terms and images referring to Native Americans/First Nations as the name or mascot for a sports team is a topic of public controversy in the United States and in Canada, arising as part of the Native American/First Nations civil rights movements. The retirement of the Washington Redskins and the Cleveland Indians has tipped public opinion in favor of eliminating Native mascots by public school, more states considering or passing legislation to do so, heeding tribal leaders who have advocating for change for decades.
Statewide laws or school board decisions mandating change have been passed in states with significant Native American population; other states also have official policies that encourage change in accordance with principles of establishing a proper environment for education. However, there has also been resistance and backlash, usually when statewide laws have been viewed as an intrusion into local communities, where no need for change has been established.
The documents most often cited to justifying the trend for change are an advisory opinion by the United States Commission on Civil Rights in 2001 and a resolution by the American Psychological Association in 2005. Both support the views of Native American organizations and individuals that such mascots maintaining harmful stereotypes that are discriminatory and cause harm by distorting the past and preventing understanding of Native American/First Nations peoples in the present.
Rex P. Shipp, the state representative for Cedar City, Utah, introduced in 2020 a joint resolution supporting "the appropriate use of names, images, and symbols of Native Americans and other indigenous people by schools or places" and discouraging "removing names, images, and symbols of Native Americans and other indigenous people from schools or places". Although not having the force of law, the resolution failed on party lines in 2021, with only a few Republicans voting in support. A similar resolution may be in |
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