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the answer to your question is yes it is certainly possible. at one time it was thought that there was something special about " organic " chemicals which meant that they could not be artificially synthesised out of fundamental elements. in 1828 frederick wohler synthesised urea ( co ( nh2 ) 2 ) which is often taken as... | https://api.stackexchange.com |
only 359 base pairs ) or prions? in a sense these are " just " very large molecules. but then really simple bacteria are not many orders of magnitude more complex. as an aside most systems of ethics that do not permit eating meat do not make an alive / non - alive distinction, choosing some other aspect such as sentien... | https://api.stackexchange.com |
cells co - operate with them properly. more in keeping with your theme would be adding photosynthetic systems directly to human cells along with a suite of enzymes to manufacture all the things we cannot. that is of course in principle scientifically possible ( since plants do it ) but much harder than it looks. living... | https://api.stackexchange.com |
the $ \ theta ( \ log n ) $ complexity is usually connected with subdivision. when using lists as an example, imagine a list whose elements are sorted. you can search in this list in $ \ mathcal { o } ( \ log n ) $ time - you do not actually need to look at each element because of the sorted nature of the list. if you ... | https://api.stackexchange.com |
cellular respiration in plants is slightly different than in other eukaryotes because the electron transport chain contains an additional enzyme called alternative oxidase ( aox ). aox takes some electrons out of the pathway prematurely - basically the energy is used to generate heat instead of atp. the exact purpose o... | https://api.stackexchange.com |
short answer healthy people cannot hold their breaths until unconsciousness sets in, let alone commit suicide. background according to parkes ( 2005 ), a normal person cannot even hold their breath to unconsciousness, let alone death. parkes says : breath ‐ holding is a voluntary act, but normal subjects appear unable ... | https://api.stackexchange.com |
i work in a lab that does global optimization of mixed - integer and non - convex problems. my experience with open source optimization solvers has been that the better ones are typically written in a compiled language, and they fare poorly compared to commercial optimization packages. if you can formulate your problem... | https://api.stackexchange.com |
best mixed - integer linear programming solvers cplex and gurobi are free for academics, so you might be able to get away with just purchasing the gams interfaces rather than the interfaces and the solver licenses, which can save you quite a bit of money. this point bears repeating : for any of the deterministic non - ... | https://api.stackexchange.com |
as well be a tao developer. with that additional information, you are more likely to get better results calling gams from python ( if that's an option at all ), or trying to patch up the ipopt python interface. since ipopt uses an interior point method, it won't be as robust, but maybe andreas'implementation of an inte... | https://api.stackexchange.com |
there's another question related to salt bridges on this site. the purpose of a salt bridge is not to move electrons from the electrolyte, rather it's to maintain charge balance because the electrons are moving from one - half cell to the other. the electrons flow from the anode to the cathode. the oxidation reaction t... | https://api.stackexchange.com |
introduction the kappa statistic ( or value ) is a metric that compares an observed accuracy with an expected accuracy ( random chance ). the kappa statistic is used not only to evaluate a single classifier, but also to evaluate classifiers amongst themselves. in addition, it takes into account random chance ( agreemen... | https://api.stackexchange.com |
number of instances. for this confusion matrix, this would be 0. 6 ( ( 10 + 8 ) / 30 = 0. 6 ). before we get to the equation for the kappa statistic, one more value is needed : the expected accuracy. this value is defined as the accuracy that any random classifier would be expected to achieve based on the confusion mat... | https://api.stackexchange.com |
. 50 ) / ( 1 - 0. 50 ) = 0. 20. as another example, here is a less balanced confusion matrix and the corresponding calculations : cats dogs cats | 22 | 9 | dogs | 7 | 13 | ground truth : cats ( 29 ), dogs ( 22 ) machine learning classifier : cats ( 31 ), dogs ( 20 ) total : ( 51 ) observed accuracy : ( ( 22 + 13 ) / 51... | https://api.stackexchange.com |
opposed to maximizing the number of animals we take in ), then a classifier with a lower kappa but better rate of classifying cats might be more ideal. second, acceptable kappa statistic values vary on the context. for instance, in many inter - rater reliability studies with easily observable behaviors, kappa statistic... | https://api.stackexchange.com |
i can improve the answer. references i found helpful : includes a succinct description of kappa : includes a description of calculating expected accuracy : | https://api.stackexchange.com |
i was in the middle of typing an answer pretty much exactly like yoda's. he's is probably the most reliable but, i'll proposed a different solution so you have some options. if you take a histogram of your signal, you will more than likely a bell or triangle like shape depending on the signal type. clean signals will t... | https://api.stackexchange.com |
i can only recommend textbooks because that's what i've used, but here are some suggestions : gravity : an introduction to general relativity by james hartle is reasonably good as an introduction, although in order to make the content accessible, he does skip over a lot of mathematical detail. for your purposes, you mi... | https://api.stackexchange.com |
gravitation and cosmology : principles and applications of the general theory of relativity by steven weinberg is another one that i've read a bit of. honestly i find it a bit hard to follow - just like some of weinberg's other books, actually - since he gets into such detailed explanations, and it's easy to get bogged... | https://api.stackexchange.com |
for the reasons explained in new point of view on the meaning and on the values of $ k _ \ mathrm { a } ( \ ce { h3o +, h2o } ) $ and $ k _ \ mathrm { b } ( \ ce { h2o, oh - } ) $ pairs in water analyst, february 1998, vol. 123 ( 409 – 410 ), the $ \ mathrm { p } k _ \ mathrm { a } $ of $ \ ce { h3o + } $ in $ \ ce { h... | https://api.stackexchange.com |
above data to say $ \ ce { d3o + } $ is stronger is misleading, because this corresponds to a reaction with $ \ ce { od - } $, not $ \ ce { d2o } $. $ \ ce { d3o + } $ simply has a lower concentration in heavy water than $ \ ce { h3o + } $ has in light water. as for why the $ \ ce { d2o } $ is less dissociated than $ \... | https://api.stackexchange.com |
– 751 explanation of normal / inverse solvent isotope effect for a kinetic normal / inverse solvent isotope effect there will be a reactant and transition state. if ( for example ) there is a single solvent exchangeable proton that is the same group in the reactant and transition state, for example, $ \ ce { roh } $ in... | https://api.stackexchange.com |
for any real matrix $ a $ and any vectors $ \ mathbf { x } $ and $ \ mathbf { y } $, we have $ $ \ langle a \ mathbf { x }, \ mathbf { y } \ rangle = \ langle \ mathbf { x }, a ^ t \ mathbf { y } \ rangle. $ $ now assume that $ a $ is symmetric, and $ \ mathbf { x } $ and $ \ mathbf { y } $ are eigenvectors of $ a $ co... | https://api.stackexchange.com |
fwiw the medium length version i usually give goes like this : you want to ask a question of a population but you can't. so you take a sample and ask the question of it instead. now, how confident you should be that the sample answer is close to the population answer obviously depends on the structure of population. on... | https://api.stackexchange.com |
all humans have some differences in their dna, but there's far more that is shared. on average the difference between humans is only about one thousandth of their full dna, which means we're about 99. 9 % the same. these differences aren't distributed fully randomly, but are often because of specific gene alternatives.... | https://api.stackexchange.com |
update - as of january 2021, samtools can now do filtering based on an expression that includes tag variables. in this case, this expression can be used to exclude any reads that have either an xa or sa tag : samtools view - b mapped. bam - e '! ( [ xa ] | [ sa ] )'> unique _ mapped. bam for more details on the samtool... | https://api.stackexchange.com |
##tgcccggcaatgaaattcgttttccgtcaattcttgaaaatttc < aabbegabfjkkkim7ghkkjk > jlkldgmhlimihhcgijkkljklnjglllklilklmfndlkghjekmkkmijhglojlllkijlkkjejligg > d nm : i : 4 md : z : 83a13 as : i : 77 xs : i : 67 xa : z : tig00019544, - 78808, 21m2i56m1i20m, 6 ; tig00019544, - 84624, 79m1i20m, 6 ; tig00019544, - 79312, 33m4i42m1... | https://api.stackexchange.com |
z : 83a13 as : i : 77 xs : i : 67... so it filtered out the tag ( i. e. the tag no longer exists in the sam output ), but not the read. there are no useful bits in the flag field to indicate multiple genomic mappings ( which i know can be filtered to exclude the read as well ), so i have to resort to other measures. in... | https://api.stackexchange.com |
5868 err063640. 6116 err063640. 6198 err063640. 6468 err063640. 6717 err063640. 6797 err063640. 7322 err063640. 750 err063640. 7570 err063640. 7900 err063640. 8115 err063640. 8405 err063640. 911 err063640. 9206 err063640. 9765 err063640. 9986 oh... damn. i wonder what they are : $ samtools view output _ filtered. bam |... | https://api.stackexchange.com |
5402, -, 58s38m, 60, 0 ; aha! supplemental alignments, which use the official sa tag [ other canonical alignments in a chimeric alignment ]. these appear to be situations where a single read has been split up, and maps to multiple locations. note that in this case, both of the alignments still have mapq scores of over ... | https://api.stackexchange.com |
it is important to understand that the only problem here is to obtain the extrinsic parameters. camera intrinsics can be measured off - line and there are lots of applications for that purpose. what are camera intrinsics? camera intrinsic parameters is usually called the camera calibration matrix, $ k $. we can write $... | https://api.stackexchange.com |
i compute homography from a planar marker? homography is an homogeneaous $ 3 \ times3 $ matrix that relates a 3d plane and its image projection. if we have a plane $ z = 0 $ the homography $ h $ that maps a point $ m = ( x, y, 0 ) ^ t $ on to this plane and its corresponding 2d point $ m $ under the projection $ p = k ... | https://api.stackexchange.com |
most of the answers so far have been along the general lines of'why hard problems are important ', rather than'why the collatz conjecture is important'; i will try to address the latter. i think the basic question being touched on is : in what ways does the prime factorization of $ a $ affect the prime factorization of... | https://api.stackexchange.com |
toothpaste is what is called a non - newtonian fluid, more specifically toothpaste is a bingham plastic. this means that the viscosity of the fluid is linearly dependent on the shear stress, but with an offset called the yield stress ( see figure below ). this yield stress is what makes it hard to say whether it is liq... | https://api.stackexchange.com |
ok, let's try to derive the best : $ $ \ begin { array } { lcl } y [ n ] & = & \ alpha x [ n ] + ( 1 - \ alpha ) y [ n - 1 ] \ \ & = & \ alpha x [ n ] + ( 1 - \ alpha ) \ alpha x [ n - 1 ] + ( 1 - \ alpha ) ^ 2 y [ n - 2 ] \ \ & = & \ alpha x [ n ] + ( 1 - \ alpha ) \ alpha x [ n - 1 ] + ( 1 - \ alpha ) ^ 2 \ alpha x [... | https://api.stackexchange.com |
= & \ frac { \ alpha ^ 2 } { 1 - ( 1 - \ alpha ) ^ 2 } + \ frac { 2 } { k } ( 1 - ( 1 - \ alpha ) ^ k ) + \ frac { 1 } { k } \ \ & = & \ frac { \ alpha ^ 2 } { 2 \ alpha - \ alpha ^ 2 } + \ frac { 2 } { k } ( 1 - ( 1 - \ alpha ) ^ k ) + \ frac { 1 } { k } \ \ & = & \ frac { \ alpha } { 2 - \ alpha } + \ frac { 2 } { k ... | https://api.stackexchange.com |
- \ frac { 2 \ alpha } { k } \ frac { 1 - ( 1 - \ alpha ) ^ k } { 1 - ( 1 - \ alpha ) } + \ frac { 1 } { k } + \ frac { \ alpha ^ 2 ( 1 - \ alpha ) ^ { 2k } } { 1 - ( 1 - \ alpha ) ^ 2 } \ end { array } $ $ simplifying it according to mathematica yields : $ $ j ( \ alpha ) = \ frac { \ alpha } { 2 - \ alpha } + \ frac ... | https://api.stackexchange.com |
{ \ tt min } $ = 0. 1533333 for $ k $ = 16. $ \ alpha _ { \ tt min } $ = 0. 08 for $ k $ = 24. $ \ alpha _ { \ tt min } $ = 0. 0533333 for $ k $ = 32. $ \ alpha _ { \ tt min } $ = 0. 04 for $ k $ = 40. $ \ alpha _ { \ tt min } $ = 0. 0333333 for $ k $ = 48. $ \ alpha _ { \ tt min } $ = 0. 0266667 for $ k $ = 56. $ \ al... | https://api.stackexchange.com |
some factors were hinted, but let me put them in an order of importance and mention some more : metals generally have a high melting point, because metallic interatomic bonding by delocalized electrons ( $ \ ce { li } $ having only a few electrons for this " electron sea " ) between core atoms is pretty effective in th... | https://api.stackexchange.com |
among the high $ z $ atoms ( compared to e. g. $ \ ce { li } $ ) is denser ( more protons, stronger attraction of shell electrons, smaller interatomic radius ), means stronger interatomic bonding transmitted by the electron sea : you can see here that in each series ( $ \ ce { li, \ na, \ k } $ ) the melting points ris... | https://api.stackexchange.com |
the key difference is that roc curves will be the same no matter what the baseline probability is, but pr curves may be more useful in practice for needle - in - haystack type problems or problems where the " positive " class is more interesting than the negative class. to show this, first let's start with a very nice ... | https://api.stackexchange.com |
my problem? ", use a pr curve. if your question is, " how well can this classifier be expected to perform in general, at a variety of different baseline probabilities? ", go with a roc curve. | https://api.stackexchange.com |
the inert pair effect describes the preference of late p - block elements ( elements of the 3rd to 6th main group, starting from the 4th period but getting really important for elements from the 6th period onward ) to form ions whose oxidation state is 2 less than the group valency. so much for the phenomenological par... | https://api.stackexchange.com |
there are two ways to efficiently make an aerosol product : use a gas that liquifies under the pressure inside the can. for example, butane lighters. nitrogen is one of the " fixed gases ", meaning it's a gas under most conditions ( but take a look at the temperatures and pressures needed for liquid nitrogen — it's not... | https://api.stackexchange.com |
no. there are sweet, bitter, and various other salts. ( likely, there are tasteless salts too ). pure salty taste is as far as i know exclusive for table salt, though i wouldn't bet on it. lead and beryllium salts are said to be sweet, though toxic. epsom salt, $ \ ce { mgso4 } $, is bitter. $ \ ce { cuso4 } $ has an i... | https://api.stackexchange.com |
a 400mah 9v battery will last a year with a 40µa current draw. now consider a smoke detector. it is low power analog circuitry, most likely drawing less than the 40µa figure above. if you wanted to power it from a boost converter and aas, then you'd need a converter with very low idle current. but... when there is fire... | https://api.stackexchange.com |
i had heard that tape is still the best medium for storing large amounts of data. well, " best " is always a reduction to a single set of optimization parameters ( e. g. cost per bit, durability,... ) and isn't ever " universally true ". i can see, for example, that " large " is already a relative term, and for a small... | https://api.stackexchange.com |
distortion " that casettes bring – but that's not anything you want to transport digital data. you must be very careful here, because audio cassette formulations are optimized for specific audio properties. that means your " perceptive " quality has little to do with the " digital data capacity ". i have a hard time be... | https://api.stackexchange.com |
that simple, because your system isn't free from noise and distortion, but as before : low cost. they simply didn't. if tape is so bad then how do they store terabaytes on it? you're comparing completely different types of tapes, and tape drives : this 100€ lto - 8 data backup tape vs this cassette tape type, of which ... | https://api.stackexchange.com |
71 ) and 8b - 10b line coding ( incorporating further overhead, that should put us at an effective rate of 0. 5 ). note how they do line coding on the medium : this is bits - to - tape, directly. clearly, this leaves room for capacity increases, if one was to use the tape as the analog medium it actually is, and combin... | https://api.stackexchange.com |
long lasting immunity is obtained by means of the adaptive immune system, and mainly involves the development of antibodies that identify specific parts ( epitopes ) of the pathogen's proteins. common cold is typically caused by a type of virus called rhinovirus. viruses have very high mutation rates, which alter the s... | https://api.stackexchange.com |
in space, the sun transfers heat via radiation to equipment and astronauts. although the sun ’ s peak emission is in the visible region ( about 500 nm ), you can see that there is also a fair amount of ir ( infrared ) and uv ( ultraviolet ) emitted as well at the top of the atmosphere. to control the surface temperatur... | https://api.stackexchange.com |
roni saiba's answer does a good job of explaining what goes into current vaccine development and why it takes so much effort, but i want to directly address the question of why we can't just grow some virus, kill it with uv and have a protective vaccine. the answer is that not all immune responses to viral antigens are... | https://api.stackexchange.com |
communicated some general understanding of the background issues. edits : this doesn't relate to the rest of my answer but i want to respond to ilmari karonen's and there is not enough room in a comment. looking at the timeline for sars - cov - 2 vaccine development gives a very misleading impression of how long it tak... | https://api.stackexchange.com |
proteins had been determined from work on sars and mers vaccines. in addition to these, a large amount of miscellaneous knowledge about coronavirus functions and the immune reactions to them had been accumulated, and this sped up development, and increased confidence in results, which allows vaccine candidate productio... | https://api.stackexchange.com |
using your definition of " falling, " heavier objects do fall faster, and here's one way to justify it : consider the situation in the frame of reference of the center of mass of the two - body system ( cm of the earth and whatever you're dropping on it, for example ). each object exerts a force on the other of $ $ f =... | https://api.stackexchange.com |
{ \ frac { r _ i r } { r _ i - r } } \ mathrm { d } r $ $ where i've chosen the negative square root because $ \ dot { r } < 0 $, and integrate it again to find $ $ t = \ frac { 1 } { \ sqrt { 2g ( m _ 1 + m _ 2 ) } } \ biggl ( \ sqrt { r _ i r _ f ( r _ i - r _ f ) } + r _ i ^ { 3 / 2 } \ cos ^ { - 1 } \ sqrt { \ frac... | https://api.stackexchange.com |
you're not looking for edges ( = borders between extended areas of high and low gray value ), you're looking for ridges ( thin lines darker or brighter than their neighborhood ), so edge filters might not be ideal : an edge filter will give you two flanks ( one on each side of the line ) and a low response in the middl... | https://api.stackexchange.com |
^ 2g } { \ partial x \, \ partial y } & \ frac { \ partial ^ 2g } { \ partial y \, ^ 2 } \ end { array } \ right ). \ left ( \ begin { array } { cc } x \ \ y \ end { array } \ right ) + \ left ( \ begin { array } { cc } \ frac { \ partial g } { \ partial x } & \ frac { \ partial g } { \ partial y } \ end { array } \ ri... | https://api.stackexchange.com |
##ue of the hessian matrix at each pixel ) on your image : as you can see, there's only a single peak for every thin dark line. binarizing and skeletonizing yields : after pruning the skeleton and removing small components ( noise ) from the image, i get this final skeleton : full mathematica code : ridges = ridgefilte... | https://api.stackexchange.com |
for a $ 2 $ player game, it's obvious that player one will play, and $ \ frac16 $ chance of losing. player $ 2 $, has a $ \ frac16 $ chance of winning on turn one, so there is a $ \ frac56 $ chance he will have to take his turn. ( i've intentionally left fractions without reducing them as it's clearer where the numbers... | https://api.stackexchange.com |
\ frac26 $, captor - $ \ frac16 $ | https://api.stackexchange.com |
here is how i would explain the basic difference to my grandma : i have misplaced my phone somewhere in the home. i can use the phone locator on the base of the instrument to locate the phone and when i press the phone locator the phone starts beeping. problem : which area of my home should i search? frequentist reason... | https://api.stackexchange.com |
there are lots of edge detection possibilities, but the 3 examples you mention happen to fall in 3 distinct categories. sobel this approximates a first order derivative. gives extrema at the gradient positions, 0 where no gradient is present. in 1d, it is = $ \ left [ \ begin { array } { ccc } - 1 & 0 & 1 \ end { array... | https://api.stackexchange.com |
the physically " correct " way to do this is summing the samples. however when you add two arbitrary samples, the resulting value could be up to twice the maximum value.... the naive solution here is to divide by n, where n is the number of channels being mixed. that's not the " naive " solution, its the only solution.... | https://api.stackexchange.com |
separate step. you mix first, with plenty of headroom, and then put it through dynamic range compression later, if desired. | https://api.stackexchange.com |
tl ; dr : it is certainly possible to build a career in applied math and computational sciences without directly contributing to arms research. it is hardly possible to build a career in any research without indirectly contributing to arms research. one can easily avoid direct contributions to military topics by choosi... | https://api.stackexchange.com |
a random process is a collection of random variables, one for each time instant under consideration. typically this may be continuous time ( $ - \ infty < t < \ infty $ ) or discrete time ( all integers $ n $, or all time instants $ nt $ where $ t $ is the sample interval ). stationarity refers to the distributions of ... | https://api.stackexchange.com |
##t } \ int _ { - t } ^ t x ( t ) \, \ mathrm dt $ $ but, what does $ \ bar { x } $ have to do with $ \ mu = e [ x ( t ) ] $, the mean of the random process? ( note that it doesn't matter which value of $ t $ we use ; all the random variables have the same distribution and so have the same mean ( if the mean exists ) )... | https://api.stackexchange.com |
' t tell, as an example of the difference between the two concepts, suppose that $ x ( t ) = y $ for all $ t $ under consideration. here $ y $ is a random variable. this is a stationary process : each $ x ( t ) $ has the same distribution ( namely, the distribution of $ y $ ), same mean $ e [ x ( t ) ] = e [ y ] $, sam... | https://api.stackexchange.com |
\ colon x ( t ) = \ cos ( t + \ theta ), - \ infty < t < \ infty \ } $ where $ \ theta $ takes on four equally likely values $ 0, \ pi / 2, \ pi $ and $ 3 \ pi / 2 $. note that each $ x ( t ) $ is a discrete random variable that, in general, takes on four equally likely values $ \ cos ( t ), \ cos ( t + \ pi / 2 ) = - ... | https://api.stackexchange.com |
$ \ pm \ cos ( t ) $ and $ \ pm \ sin ( t ) $ which have dc value $ 0 $ which equals $ 0 $, and whose autocorrelation function is $ \ frac 12 \ cos ( \ tau ) $, same as $ r _ x ( \ tau ) $, and so this process is mean - ergodic and autocorrelation - ergodic even though it is not stationary at all. in closing, i remark ... | https://api.stackexchange.com |
you are absolutely right, flushing down the toilet ( or the sink ) or simply throwing them into the normal waste doesn't work for biosafety reasons. and it is also not allowed, depending on the country you would do this in, this can lead to hefty fines. biologically contaminated lab waste can be inactivated ( = all pot... | https://api.stackexchange.com |
nitrile gloves are made of nitrile rubber, or poly ( butadiene / acrylonitrile ). this polymer is highly soluble in chloroform, with some papers i found indicating that one can dissolve up to 18 % in mass of nitrile butadiene rubber in chloroform. moreover, it permeates easily through nbr, meaning we can expect the dis... | https://api.stackexchange.com |
atoms at the edge of a crystal that have an unsatisfied valence are said to have " dangling bonds. " many elements, in addition to carbon, can have dangling bonds. dangling bonds is a subject of current interest because of the impact these structures can have on semiconductor properties. these dangling bonds are very s... | https://api.stackexchange.com |
just for visual amusement, here are more pictures. in all cases, initial point is a large red dot. primes up to $ 10 ^ 5 $ : primes up to $ 10 ^ 6 $ : primes up to $ 10 ^ 6 $ starting gaps of length $ > 6 $ : primes up to $ 10 ^ 7 $ starting gaps of length $ > 10 $ : primes up to $ 10 ^ 8 $ starting gaps of length $ > ... | https://api.stackexchange.com |
can anyone give some recommendations / experiences on which license to pick for software? which license you chose will depend on how free you want your code to be, but free means different things to different people. for proponents of permissive licenses, free means allowing people now to use the software however they ... | https://api.stackexchange.com |
then you could consider the affero gpl which plugs that particular copyleft loophole. thirdly, you can do the above and offer a dual license option. offering gpl or agpl licenses for public download, and commercial licenses for a fee gives you the best of both worlds, and means that you might even be able to generate s... | https://api.stackexchange.com |
for organic matter, such as bread and human skin, cutting is a straightforward process because cells / tissues / proteins / etc can be broken apart with relatively little energy. this is because organic matter is much more flexible and the molecules bind through weak intermolecular interactions such as hydrogen bonding... | https://api.stackexchange.com |
this seems a very basic question to me, so excuse me if i lecture you a bit. the most important point for you to learn here is that a number is not its digit representation. a number is an abstract mathematical object, whereas its digit representation is a concrete thing, namely a sequence of symbols on a paper ( or a ... | https://api.stackexchange.com |
, 2, 0 ], 3, 2 ) [ 1, 0, 1, 0, 1, 0 ] note : we did not pass through base 10 representation! we converted the base $ b $ representation to the number, and then the number to base $ c $. the number was not in any representation. ( actually it was, the computer had to represent it somehow, and it did represent it using e... | https://api.stackexchange.com |
i'd like to quote an answer from stack overflow by hstoerr which covers the problem nicely : that heavily depends on the structure of the search tree and the number and location of solutions. if you know a solution is not far from the root of the tree, a breadth first search ( bfs ) might be better. if the tree is very... | https://api.stackexchange.com |
the feynman lectures need only a little amending, but it's a relatively small amount compared to any other textbook. the great advantage of the feynman lectures is that everything is worked out from scratch feynman's way, so that it is taught with the maximum insight, something that you can only do after you sit down a... | https://api.stackexchange.com |
from volume i, since computers were not available at the time it was written. it's not completely missing, however, and it's much worse elsewhere. the kepler problem : feynman has an interesting point of view regarding this which is published in the " lost lecture " book and audio - book. but i think the standard metho... | https://api.stackexchange.com |
centered, but he didn't get to do it. somebody else did a vector - potential based discussion of e & m based on this recommendation, but the results were not so great. the major things i don't like in vol. ii : the derivation of the index of refraction is done by a complicated rescattering calculation which is based on... | https://api.stackexchange.com |
equation : this part is not done in any book, i think only because dirac omitted it from his. it is essential to know how to boost wavefunctions. since feynman derives the schrodinger equation from a tight - binding model ( a lattice approximation ), the galilean invariance is not obvious at all. since the lectures are... | https://api.stackexchange.com |
for an exact calculation we need to address a few choices : ( you can change them, the answer will not be tremendously affected ) what is the receiver? let's assume a 70 m dish, like this one [ cdscc ] in the deep space network. [ voyager 1 ] can transmit at $ 2. 3 { \ rm ghz } $ or $ 8. 4 { \ rm ghz } $. let's assume ... | https://api.stackexchange.com |
{ \ pi d } { \ lambda } \ big ) ^ 2 \ \ frac1 { 4 \ pi r ^ 2 } \ \ frac { \ pi d ^ 2 } 4 $ $ dividing by $ e _ \ phi $ we see that this power then still corresponds to c. $ 240000 $ photons per second, or $ 1500 $ photons per bit. if we assume $ f = 2. 3 { \ rm ghz } $ this becomes $ 415 $ photons per bit. and if we in... | https://api.stackexchange.com |
i tend to use ensembl biomart for such queries since there are apis for various programming languages, e. g. biomart, and, maybe more interestingly, via a rest api ( although it ’ s a pretty terrible one ). to translate identifiers from different databases, proceed as follows : choose database “ ensembl genes ” choose ... | https://api.stackexchange.com |
why do you want to know? i'm not kidding. that's actually an important question. the answer really depends on what you intend to do with the information you are given. newton's laws are an empirical model. newton ran a bunch of studies on how things moved, and found a small set of rules which could be used to predict w... | https://api.stackexchange.com |
it might not work. test them. most of the time, you'll find that the law holds up perfectly. when it doesn't hold up, come back here with your experiment, and we can help you learn how to explain the results you saw. that's science. science isn't about a classroom full of equations and homework assignments. it's about ... | https://api.stackexchange.com |
does the flap of a butterfly's wing in brazil set off a tornado in texas? this was the whimsical question edward lorenz posed in his 1972 address to the 139th meeting of the american association for the advancement of science. some mistakenly think the answer to that question is " yes. " ( otherwise, why would he have ... | https://api.stackexchange.com |
##ministic system. in a sense, asking which tiny little perturbation ultimately caused a tornado in texas to occur doesn't make sense. if the flap of one butterfly's wing in brazil could indeed set off a tornado in texas, this means the flap of the wing of another butterfly in brazil could prevent that tornado from occ... | https://api.stackexchange.com |
^ { 24 } $ particles. first off, good luck making a physically realistic simulation of a system comprising that many particles that can be resolved in a realistic amount of time. secondly, that value represents a mere 0. 06 cubic meters of air at standard temperature and pressure. a system of on the order of 1024 parti... | https://api.stackexchange.com |
this is not really a biological answer, but a psychological one : one important fact to consider is that the perception of time is essentially a recollection of past experience, rather than perception of the present. researchers who study autobiographical memory have suggested that part of this effect may be explained ... | https://api.stackexchange.com |
this is certainly true. suppose $ n ^ 3 - 1 $ is prime, for some $ n $. we get that $ n ^ 3 - 1 = ( n - 1 ) ( n ^ 2 + n + 1 ) $ and so we have that $ n - 1 $ divides $ n ^ 3 - 1 $. if $ n - 1 > 1 $ then we're done, as we have a contradiction to $ n ^ 3 - 1 $ being prime. | https://api.stackexchange.com |
1. capacitors there are a lot of misconceptions about capacitors, so i wanted to briefly clarify what capacitance is and what capacitors do. capacitance measures how much energy will be stored in the electric field generated between two different points for a given difference of potential. this is why capacitance is of... | https://api.stackexchange.com |
##s beyond, we are at the mercy of physics. like any good engineer, in the face of limits imposed by the laws of nature, we cheat and get around those limits anyway. electrolytic capacitors and high capacitance ( 0. 1µf to 100µf + ) ceramic capacitors are the dirty tricks we used. 2. electrolytic capacitors aluminum th... | https://api.stackexchange.com |
supply, and let the voltage rise slowly until it reaches its rated voltage. this prevents the very high leakage current ( initially ) from damaging the capacitor, and slowly rebuilds the surface oxides until the leakage is hopefully at acceptable levels. the other problem is that electrolytes are, due to chemistry, som... | https://api.stackexchange.com |
##um and manganese dioxide can undergo a reaction similar to thermite, which is aluminum and iron oxide. only, the tantalum reaction has much lower activation temperatures - temperatures that are easily and quickly achieved should opposite polarity or an overvoltage event punch a hole through the dielectric ( tantalum ... | https://api.stackexchange.com |
their effectiveness with medium frequencies ( the best and smallest ones can almost hit 1mhz, most lose their capacitive characteristic around 300 – 600khz ). all in all, electrolytic capacitors are great for storing a ton of energy in a small space, but are really only useful for dealing with noise or ripple below 100... | https://api.stackexchange.com |
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