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Business Statistics Significance Statistical_methodology > Methods > Inferential statistics > Terminology and theory of inferential statistics > Significance Although these are produced from the same calculations as those of hypothesis tests or p-values, they describe both the size of the effect and the uncertainty surrounding it. Fallacy of the transposed conditional, aka prosecutor's fallacy: criticisms arise because the hypothesis testing approach forces one hypothesis (the null hypothesis) to be favored, since what is being evaluated is the probability of the observed result given the null hypothesis and not probability of the null hypothesis given the observed result. An alternative to this approach is offered by Bayesian inference, although it requires establishing a prior probability. Rejecting the null hypothesis does not automatically prove the alternative hypothesis. As everything in inferential statistics it relies on sample size, and therefore under fat tails p-values may be seriously mis-computed.
Fisher's exact test Controversies Fisher's_exact_test > Controversies It is possible to obtain an exact p-value for the 2×2 table when the margins are not held fixed. Barnard's test, for example, allows for random margins.
Multiseat desktop virtualization Introduction Multiseat_desktop_virtualization > Introduction It is commonly known that modern day PCs are extremely powerful and have substantial excess CPU processing power. In fact, most desktop applications do not use the multi-core capabilities of today's CPUs. When an application is launched it runs on the first core, and when a second application is launched, it continues to run on the first core. That process continues (with the second and subsequent cores basically idling) until the original core gets very busy. At that point, the operating system tells the new applications to run on the second and subsequent cores.
Porocyte Summary Porocyte Porocytes are tubular cells which make up the pores of a sponge known as ostia.
Sliding window protocol Summary Sliding_window_protocol The paradigm is similar to a window sliding sideways to allow entry of fresh packets and reject the ones that have already been acknowledged. When the receiver verifies the data, it sends an acknowledgment signal, or "ACK", back to the sender to indicate it can send the next packet. In a simple automatic repeat request protocol (ARQ), the sender stops after every packet and waits for the receiver to ACK.
Antituberculous drug Extra-pulmonary tuberculosis Tuberculostatic_drug > Standard regimen > Extra-pulmonary tuberculosis In these situations, all that is required is re-assurance. Steroids may be useful in resolving the swelling, especially if it is painful, but they are unnecessary. Additional antibiotics are unnecessary and the treatment regimen does not need to be lengthened.There is no evidence that 6 months regimen is inadequate in treating abdominal TB and there is no additional benefits for 9-month regimen for preventing relapse. However, more large scale studies are needed to confirm the above conclusion.
Eigenface Summary Eigenface The eigenfaces themselves form a basis set of all images used to construct the covariance matrix. This produces dimension reduction by allowing the smaller set of basis images to represent the original training images. Classification can be achieved by comparing how faces are represented by the basis set.
Transcription factors Accessibility of DNA-binding site Gene_transcription_factor > Regulation > Accessibility of DNA-binding site In eukaryotes, DNA is organized with the help of histones into compact particles called nucleosomes, where sequences of about 147 DNA base pairs make ~1.65 turns around histone protein octamers. DNA within nucleosomes is inaccessible to many transcription factors. Some transcription factors, so-called pioneer factors are still able to bind their DNA binding sites on the nucleosomal DNA. For most other transcription factors, the nucleosome should be actively unwound by molecular motors such as chromatin remodelers.
Faà di Bruno's formula Example Faà_di_Bruno's_formula > Example 1 ! + ( f ( 2 ) ∘ g ) g ( 1 ) 1 ! 1 !
Surface stress Thermodynamics of surface stress Surface_stress > Thermodynamics of surface stress Then surface stress can be expressed as: f i j = γ δ i j + ∂ γ / ∂ e i j {\displaystyle f_{ij}=\gamma \delta _{ij}+\partial \gamma /\partial e_{ij}} Where δij is the Kronecker delta and eij is elastic strain tensor. Differently from the surface free energy γ, which is a scalar, surface stress fij is a second rank tensor.
Antenna proteins Summary Light-harvesting_complexes_of_green_plants The light-harvesting complex (or antenna complex; LH or LHC) is an array of protein and chlorophyll molecules embedded in the thylakoid membrane of plants and cyanobacteria, which transfer light energy to one chlorophyll a molecule at the reaction center of a photosystem. The antenna pigments are predominantly chlorophyll b, xanthophylls, and carotenes. Chlorophyll a is known as the core pigment. Their absorption spectra are non-overlapping and broaden the range of light that can be absorbed in photosynthesis.
Benzyne Nucleophilic additions to arynes Benzyne_mechanism > Reactions of arynes > Nucleophilic additions to arynes In case of triple bond located between C2 and C3, electron withdrawing (EWG) substituents, e.g. CF3, will direct the nucleophile addition to place carbanion as close as possible to EWG. However, electron donating (EDG) substituents, e.g. CH3, will provide little selectivity between products. In the regioisomer where triple bond is located between C3 and C4 the effect of substituent on nucleophile addition is diminished, and mixtures of para and meta products are often obtained.
Partial index Summary Partial_index In databases, a partial index, also known as filtered index is an index which has some condition applied to it so that it includes a subset of rows in the table. This allows the index to remain small, even though the table may be rather large, and have extreme selectivity. Suppose you have a transaction table where entries start out with STATUS = 'A' (active), and then may pass through other statuses ('P' for pending, 'W' for "being worked on") before reaching a final status, 'F', at which point it is no longer likely to be processed again. In PostgreSQL, a useful partial index might be defined as: This index would not bother storing any of the millions of rows that have reached "final" status, 'F', and would allow queries looking for transactions that still "need work" to efficiently search via this index. Similarly, a partial index can be used to index only those rows where a column is not null, which will be of benefit when the column usually is null. This index would allow the following query to read only the updated tuples: It is not necessary that the condition be the same as the index criterion; Stonebraker's paper below presents a number of examples with indexes similar to the following:
Six Sigma Over-reliance on statistics Six_Sigma > Criticism > Over-reliance on statistics More direct criticism is the "rigid" nature of Six Sigma with its over-reliance on methods and tools. In most cases, more attention is paid to reducing variation and searching for any significant factors, and less attention is paid to developing robustness in the first place (which can altogether eliminate the need for reducing variation). The extensive reliance on significance testing and use of multiple regression techniques increase the risk of making commonly unknown types of statistical errors or mistakes. A possible consequence of Six Sigma's array of p-value misconceptions is the false belief that the probability of a conclusion being in error can be calculated from the data in a single experiment without reference to external evidence or the plausibility of the underlying mechanism.
Third derivative Summary Third_derivative In calculus, a branch of mathematics, the third derivative or third-order derivative is the rate at which the second derivative, or the rate of change of the rate of change, is changing. The third derivative of a function y = f ( x ) {\displaystyle y=f(x)} can be denoted by d 3 y d x 3 , f ‴ ( x ) , or d 3 d x 3 . {\displaystyle {\frac {d^{3}y}{dx^{3}}},\quad f'''(x),\quad {\text{or }}{\frac {d^{3}}{dx^{3}}}.} Other notations can be used, but the above are the most common.
Fat embolism Pathophysiology Fat_embolism > Pathophysiology Since venous blood returns to the right heart and is pumped to the lungs for reoxygenation, the fat globules often get lodged in the pulmonary circulation. Fat globules may also pass through lung circulation back into the left ventricle of the heart to be pumped throughout the body in the systemic circulation. They may also reach the systemic circulation through a patent foramen ovale (a hole communicating the right atrium directly to the left atrium of the heart).
Non-standard RAID levels Unraid Non-standard_RAID_levels > Unraid Unraid is a proprietary Linux-based operating system optimized for media file storage. Unfortunately Unraid doesn't provide information about its storage technology, but some say its parity array is a rewrite of the mdadm module. Disadvantages include closed-source code, high price, slower write performance than a single disk and bottlenecks when multiple drives are written concurrently. However, Unraid allows support of a cache pool which can dramatically speed up the write performance. Cache pool data can be temporarily protected using Btrfs RAID 1 until Unraid moves it to the array based on a schedule set within the software.Advantages include lower power consumption than standard RAID levels, the ability to use multiple hard drives with differing sizes to their full capacity and in the event of multiple concurrent hard drive failures (exceeding the redundancy), only losing the data stored on the failed hard drives compared to standard RAID levels which offer striping in which case all of the data on the array is lost when more hard drives fail than the redundancy can handle.
Carathéodory function Summary Carathéodory_function In mathematical analysis, a Carathéodory function (or Carathéodory integrand) is a multivariable function that allows us to solve the following problem effectively: A composition of two Lebesgue-measurable functions does not have to be Lebesgue-measurable as well. Nevertheless, a composition of a measurable function with a continuous function is indeed Lebesgue-measurable, but in many situations, continuity is a too restrictive assumption. Carathéodory functions are more general than continuous functions, but still allow a composition with Lebesgue-measurable function to be measurable. Carathéodory functions play a significant role in calculus of variation, and it is named after the Greek mathematician Constantin Carathéodory.
Atkinson-Shiffrin memory model Division and nature of working memory Atkinson-Shiffrin_memory_model > Criticism > Division and nature of working memory Baddeley and Hitch have in turn called to question the specific structure of the short-term store, proposing that it is subdivided into multiple components. While the different components were not specifically addressed in the original Atkinson-Shiffrin model, the authors do note that little research has been done investigating the different ways sensory modalities may be represented in the short-term store. Thus the model of working memory given by Baddeley and Hitch should be viewed as a refinement of the original model.
Interpretability (machine learning) Goals Inscrutable_artificial_intelligence > Goals In another 2017 system, a supervised learning AI tasked with grasping items in a virtual world learned to cheat by placing its manipulator between the object and the viewer in a way such that it falsely appeared to be grasping the object.One transparency project, the DARPA XAI program, aims to produce "glass box" models that are explainable to a "human-in-the-loop" without greatly sacrificing AI performance. Human users of such a system can understand the AI's cognition (both in real-time and after the fact) and can determine whether to trust the AI. Other applications of XAI are knowledge extraction from black-box models and model comparisons.
Intel i860 Performance Intel_i860 > Performance The entire i860 design was based on the compiler efficiently handling this task, which proved almost impossible in practice. While theoretically capable of peaking at about 60-80 MFLOPS for both single precision and double precision for the XP versions, manually written assembler code managed to get only about up to 40 MFLOPS, and most compilers had difficulty getting even 10 MFLOPs. The later Itanium architecture, also a VLIW design, suffered again from the problem of compilers incapable of delivering sufficiently optimized code.
Sieve analysis Engineering applications Sieve_analysis > Engineering applications Gradation is usually specified for each engineering application it is used for. For example, foundations might only call for coarse aggregates, and therefore an open gradation is needed. Sieve analysis determines the particle size distribution of a given soil sample and hence helps in easy identification of a soil's mechanical properties. These mechanical properties determine whether a given soil can support the proposed engineering structure. It also helps determine what modifications can be applied to the soil and the best way to achieve maximum soil strength.
Surface hopping Summary Surface_hopping Surface hopping is a mixed quantum-classical technique that incorporates quantum mechanical effects into molecular dynamics simulations. Traditional molecular dynamics assume the Born-Oppenheimer approximation, where the lighter electrons adjust instantaneously to the motion of the nuclei. Though the Born-Oppenheimer approximation is applicable to a wide range of problems, there are several applications, such as photoexcited dynamics, electron transfer, and surface chemistry where this approximation falls apart. Surface hopping partially incorporates the non-adiabatic effects by including excited adiabatic surfaces in the calculations, and allowing for 'hops' between these surfaces, subject to certain criteria.
History of entropy Statistical thermodynamic views History_of_entropy > Statistical thermodynamic views Schrödinger used the Boltzmann equation in a different form to show increase of entropy S = k B ln ⁡ D {\displaystyle S=k_{\rm {B}}\ln D\!} where D is the number of possible energy states in the system that can be randomly filled with energy. He postulated a local decrease of entropy for living systems when (1/D) represents the number of states that are prevented from randomly distributing, such as occurs in replication of the genetic code.
Antikythera mechanism Proposed gear schemes Antikythera_mechanism > Reconstruction efforts > Proposed gear schemes They suggested that rather than accurate planetary indication (rendered impossible by the offset inscriptions) there would be simple dials for each individual planet, showing information such as key events in the cycle of planet, initial and final appearances in the night sky, and apparent direction changes. This system would lead to a much simplified gear system, with much reduced forces and complexity, as compared to Wright's model.Their proposal used simple meshed gear trains and accounted for the previously unexplained 63 toothed gear in fragment D. They proposed two face plate layouts, one with evenly spaced dials, and another with a gap in the top of the face, to account for criticism that they did not use the apparent fixtures on the b1 gear. They proposed that rather than bearings and pillars for gears and axles, they simply held weather and seasonal icons to be displayed through a window.
FokI DNA-binding domain FokI > DNA-binding domain The recognition domain contains three subdomains (D1, D2 and D3) that are evolutionarily related to the DNA-binding domain of the catabolite gene activator protein which contains a helix-turn-helix.
Hash table Hash function Hash_table > Hash function , m − 1 } {\displaystyle h:U\rightarrow \{0,...,m-1\}} to array indices or slots within the table for each h ( x ) ∈ 0 , . . . , m − 1 {\displaystyle h(x)\in {0,...,m-1}} where x ∈ S {\displaystyle x\in S} and m < n {\displaystyle m
State space (physics) Quantum Mechanics State_space_(physics) > Quantum Mechanics Having an nonzero component along multiple dimensions is called a superposition. These state vectors, using Dirac's bra–ket notation, can often be treated like coordinate vectors and operated on using the rules of linear algebra. This Dirac formalism of quantum mechanics can replace calculation of complicated integrals with simpler vector operations.
Synthetic hormones Summary Hormonal_medication Some hormones, such as insulin and growth hormones, can be released into the bloodstream already fully active. Other hormones, called prohormones, must be activated in certain cells through a series of steps that are usually tightly controlled. The endocrine system secretes hormones directly into the bloodstream, typically via fenestrated capillaries, whereas the exocrine system secretes its hormones indirectly using ducts.
Index of chemical engineering articles R Index_of_chemical_engineering_articles > R Rate equation -- Reverse osmosis --
S phase Summary S_phase S phase (Synthesis Phase) is the phase of the cell cycle in which DNA is replicated, occurring between G1 phase and G2 phase. Since accurate duplication of the genome is critical to successful cell division, the processes that occur during S-phase are tightly regulated and widely conserved.
Ischemic injury Occlusion Ischemic_injury > Causes > Occlusion The thrombi may dislodge and may travel anywhere in the circulatory system, where they may lead to pulmonary embolus, an acute arterial occlusion causing the oxygen and blood supply distal to the embolus to decrease suddenly. The degree and extent of symptoms depend on the size and location of the obstruction, the occurrence of clot fragmentation with embolism to smaller vessels, and the degree of peripheral arterial disease (PAD). Thromboembolism (blood clots) Embolism (foreign bodies in the circulation, e.g. amniotic fluid embolism)
Doppler imaging History Doppler_imaging > History Doppler imaging was first used to map chemical peculiarities on the surface of Ap stars. For mapping starspots it was first used by Steven Vogt and Donald Penrod in 1983, when they demonstrated that signatures of starspots were observable in the line profiles of the active binary star HR 1099 (V711 Tau); from this they could derive an image of the stellar surface.
Prokaryotic DNA replication Elongation Prokaryotic_DNA_replication > Elongation Heading towards the replication fork, the leading strand is synthesized in a continuous fashion, only requiring one primer. On the other hand, the lagging strand, heading away from the replication fork, is synthesized in a series of short fragments known as Okazaki fragments, consequently requiring many primers. The RNA primers of Okazaki fragments are subsequently degraded by RNase H and DNA Polymerase I (exonuclease), and the gaps (or nicks) are filled with deoxyribonucleotides and sealed by the enzyme ligase.
Internet of Everything Manufacturing Internet_Of_Things > Applications > Industrial > Manufacturing The IoT can connect various manufacturing devices equipped with sensing, identification, processing, communication, actuation, and networking capabilities. Network control and management of manufacturing equipment, asset and situation management, or manufacturing process control allow IoT to be used for industrial applications and smart manufacturing. IoT intelligent systems enable rapid manufacturing and optimization of new products and rapid response to product demands.Digital control systems to automate process controls, operator tools and service information systems to optimize plant safety and security are within the purview of the IIoT. IoT can also be applied to asset management via predictive maintenance, statistical evaluation, and measurements to maximize reliability. Industrial management systems can be integrated with smart grids, enabling energy optimization. Measurements, automated controls, plant optimization, health and safety management, and other functions are provided by networked sensors.In addition to general manufacturing, IoT is also used for processes in the industrialization of construction.
Chemical Science Subdisciplines Molecular_chemistry > Practice > Subdisciplines Physical chemistry has large overlap with molecular physics. Physical chemistry involves the use of infinitesimal calculus in deriving equations. It is usually associated with quantum chemistry and theoretical chemistry.
Continuous Integration Automate the build Continuous_Integration > Common practices > Automate the build A single command should have the capability of building the system. Many build tools, which have existed for many years like make, and other more recent tools are frequently used in continuous integration environments to automate building. (E.g. Makefile, which contains a set of rules for building software, can be used automate the make build process.) Automation of the build should include automating the integration, which often includes deployment into a production-like environment. In many cases, the build script not only compiles binaries but also generates documentation, website pages, statistics and distribution media (such as Debian DEB, Red Hat RPM or Windows MSI files).
Faulhaber's formula Relationship to Riemann zeta function Bernoulli's_formula > Relationship to Riemann zeta function Using B k = − k ζ ( 1 − k ) {\displaystyle B_{k}=-k\zeta (1-k)} , one can write If we consider the generating function G ( z , n ) {\displaystyle G(z,n)} in the large n {\displaystyle n} limit for ℜ ( z ) < 0 {\displaystyle \Re (z)<0} , then we find Heuristically, this suggests that This result agrees with the value of the Riemann zeta function ζ ( s ) = ∑ n = 1 ∞ 1 n s {\textstyle \zeta (s)=\sum _{n=1}^{\infty }{\frac {1}{n^{s}}}} for negative integers s = − p < 0 {\displaystyle s=-p<0} on appropriately analytically continuing ζ ( s ) {\displaystyle \zeta (s)} .
Edward Flatau Migraine and headaches Edward_Flatau > Scientific accomplishments > Migraine and headaches In 1912, he published in German and Polish one of the first modern monographs in the 20th century about migraine headaches which is still referenced in scientific literature. It was the first Polish textbook devoted to migraine. In a review of the historical background of general aspects of the headaches, Isler and Rose say, "His unique monograph of 1912, Die Migrane, contains a thoroughly structured survey of most earlier authors, precise clinical observations, a critical evaluation of pathophysiology, and uncritical opinions on treatment, including arsenic cures." In his monograph, Flatau presented the full clinical picture of migraine and described the disease as an innate disposition to pathological metabolic processes in the nervous system and described its distinguished characters – ocular, epileptic, mental and facial.
Young's syndrome Summary Young's_syndrome Young's syndrome, also known as azoospermia sinopulmonary infections, sinusitis-infertility syndrome and Barry-Perkins-Young syndrome, is a rare condition that encompasses a combination of syndromes such as bronchiectasis, rhinosinusitis and reduced male fertility. In individuals with this syndrome the functioning of the lungs is usually normal but the mucus is abnormally viscous. The reduced fertility (obstructive azoospermia) is due to functional obstruction of sperm transport down the genital tract at the epididymis, where the sperm is found in viscous, lipid-rich fluid. The syndrome was named after Donald Young, the urologist who first made observations of the clinical signs of the syndrome in 1972. Possible causes include genetics, and exposure to mercury during childhood, but the cause is unknown.
Race hazard Sequential Consistency for Data Race Freedom Race_hazard > In software > Example definitions of data races in particular concurrency models > Sequential Consistency for Data Race Freedom However, its use does allow a programmer to reason about the possible behaviors of a program in a simple way; the behavior of a correctly synchronized program is much less dependent on possible reorderings. Without correct synchronization, very strange, confusing and counterintuitive behaviors are possible.
Transistor beta Amplifiers Bipolar_Junction_Transistor > Applications > Amplifiers The transistor parameters α and β characterize the current gain of the BJT. It is this gain that allows BJTs to be used as the building blocks of electronic amplifiers. The three main BJT amplifier topologies are: Common emitter Common base Common collector
Therapeutic hypothermia Mechanism Therapeutic_hypothermia > Mechanism In general, cell death is not directly caused by oxygen deprivation, but occurs indirectly as a result of the cascade of subsequent events. Cells need oxygen to create ATP, a molecule used by cells to store energy, and cells need ATP to regulate intracellular ion levels. ATP is used to fuel both the importation of ions necessary for cellular function and the removal of ions that are harmful to cellular function.
Optical device History Optical_physicist > History This work led to a theory of diffraction for light and opened an entire area of study in physical optics. Wave optics was successfully unified with electromagnetic theory by James Clerk Maxwell in the 1860s.The next development in optical theory came in 1899 when Max Planck correctly modelled blackbody radiation by assuming that the exchange of energy between light and matter only occurred in discrete amounts he called quanta. In 1905, Albert Einstein published the theory of the photoelectric effect that firmly established the quantization of light itself.
A* algorithm Optimality and consistency A_search_algorithm > Properties > Optimality and consistency This result does not hold if A's heuristic is admissible but not consistent. In that case, Dechter and Pearl showed there exist admissible A-like algorithms that can expand arbitrarily fewer nodes than A on some non-pathological problems.
VSim Visualization VSim > Visualization Vorpal output files can be visualized within VSimComposer. Plots include those for particle data, field data, and simulation geometry, with lineouts for inspecting critical variations. The visualization within VSimComposer is accomplished by embedding the powerful VisIt tool, which users can download for more specific visualizations. Use of the VsH5 package along with popular Python tools like matplotlib allows creation of high-quality publication ready plots.
Hagia Sophia Hurrem Sultan Bathhouse Architecture Hagia_Sophia_Hurrem_Sultan_Bathhouse > Architecture There are toilets, roofed with three domes, on one side of the cool room, with a shaving room on the other side A door leads into the cross-shaped hot room, which has four loggias with fountains in the corners, and four self-contained cubicles for privacy (halvet) under a small dome. In the centre of the hot room is a large octagonal marble table called a göbektaşı (literally: navel stone), which bathers can lie on. It was formerly decorated with mosaics. The large dome of the hot room, which sits on the octagonal-shaped walls, has small glass windows to create a half-light from the top. The women's section has the same architectural plan as the men's side, although its changing room is slightly smaller.
Relativistic quantum mechanics Quantum theory and applications in general Relativistic_quantum_mechanics > Further reading > Quantum theory and applications in general (2002). Relativistic Electronic Structure Theory - Fundamentals. Theoretical and Computational Chemistry.
"grill" method Top sheet "grill"_method > Grill > Top sheet Rejewski states, "If permutation S actually were the identity, then ... for a particular we would obtain the same value for all expressions Q and in this way we would find the setting of drum N. Permutation S does exist, however, so for no will the expression Q be equal to each other, but among them will be a certain similarity for a particular , since permutation S does not change all the letters." Rejewski states that writing down all the possible Q "would be too laborious", so he developed the grill (grid) method. "Next, the grid is moved along the paper on which the drum connections are written until it hits upon a position where some similarities show up among the several expression Q.
Topological continuity Definition in terms of limits of functions Left_continuous > Real functions > Definition > Definition in terms of limits of functions Third, the value of this limit must equal f ( c ) . {\displaystyle f(c).} (Here, we have assumed that the domain of f does not have any isolated points.)
RNA silencing Three prime untranslated regions and microRNAs RNA_silencing > Background > Three prime untranslated regions and microRNAs Three prime untranslated regions (3'UTRs) of messenger RNAs (mRNAs) often contain regulatory sequences that post-transcriptionally cause RNA interference. Such 3'-UTRs often contain both binding sites for microRNAs (miRNAs) as well as for regulatory proteins. By binding to specific sites within the 3'-UTR, miRNAs can decrease gene expression of various mRNAs by either inhibiting translation or directly causing degradation of the transcript. The 3'-UTR also may have silencer regions that bind repressor proteins that inhibit the expression of a mRNA.
Church–Turing thesis Later developments Church–Turing_thesis > History > Later developments "In the late 1990s Wilfried Sieg analyzed Turing's and Gandy's notions of "effective calculability" with the intent of "sharpening the informal notion, formulating its general features axiomatically, and investigating the axiomatic framework". In his 1997 and 2002 work Sieg presents a series of constraints on the behavior of a computor—"a human computing agent who proceeds mechanically". These constraints reduce to: "(B.1) (Boundedness) There is a fixed bound on the number of symbolic configurations a computor can immediately recognize.
Zion (The Matrix) Religious meaning Zion_(The_Matrix) > Religious meaning Stephen Faller writes in his 2004 book Beyond the Matrix that Christianity is the most dominant religious theme in the Matrix films and that "Zion is biblically regarded as the city of God". The 2005 book Philosophers Explore the Matrix writes that "The last remaining human city, Zion, synonymous in Judaism and Christianity with (the heavenly) Jerusalem".
Matrix completion Summary Matrix_completion Without any restrictions on the number of degrees of freedom in the completed matrix this problem is underdetermined since the hidden entries could be assigned arbitrary values. Thus we require some assumption on the matrix to create a well-posed problem, such as assuming it has maximal determinant, is positive definite, or is low-rank.For example, one may assume the matrix has low-rank structure, and then seek to find the lowest rank matrix or, if the rank of the completed matrix is known, a matrix of rank r {\displaystyle r} that matches the known entries. The illustration shows that a partially revealed rank-1 matrix (on the left) can be completed with zero-error (on the right) since all the rows with missing entries should be the same as the third row.
Specific entropy Carnot cycle Entropy > Definitions and descriptions > Carnot cycle In fact, an entropy change in the both thermal reservoirs per Carnot cycle is also zero since that change is simply expressed by reverting the sign of each term in the equation (3) according to the fact that, for example, for heat transfer from the hot reservoir to the engine, the engine receives the heat while the hot reservoir loses the same amount of the heat; where we denote an entropy change for a thermal reservoir by ΔSr,i = - Qi/Ti, for i as either H (Hot reservoir) or C (Cold reservoir), by considering the above-mentioned signal convention of heat for the engine. Clausius then asked what would happen if less work is produced by the system than that predicted by Carnot's principle for the same thermal reservoir pair and the same heat transfer from the hot reservoir to the engine QH. In this case, the right-hand side of the equation (1) would be the upper bound of the work output by the system, and the equation would now be converted into an inequalityWhen the equation (2) is used to express the work as a net or total heat exchanged in a cycle, we getorby considering the sign convention of heat where QH > 0 is heat that is from the hot reservoir and is absorbed by the engine and QC < 0 is the waste heat given off to the cold reservoir from the engine.
Game without a value Game value Game_without_a_value > Game value The payoff function of Sion and Wolfe's example is not semicontinuous. However, it may be made so by changing the value of K(x, x) and K(x, x + 1/2) (the payoff along the two discontinuities) to either +1 or −1, making the payoff upper or lower semicontinuous, respectively. If this is done, the game then has a value.
Gene–environment correlation Definition Gene–environment_correlation > Definition Three causal mechanisms giving rise to gene–environment correlations have been described. (i) Passive gene–environment correlation refers to the association between the genotype a child inherits from their parents and the environment in which the child is raised. Parents create a home environment that is influenced by their own heritable characteristics.
Planar Separator Theorem Divide and conquer algorithms Planar_Separator_Theorem > Applications > Divide and conquer algorithms Rerooting single-source distances: The distances from r {\displaystyle r} in G {\displaystyle G} are transformed into nonnegative lengths, and again Dijkstra's algorithm is used to compute distances from s {\displaystyle s} . This stage requires O ( n log ⁡ n ) {\displaystyle O(n\log n)} time.An important part of this algorithm is the use of price functions and reduced lengths. For a directed graph G {\displaystyle G} with arc-lengths ℓ ( u v ) {\displaystyle \ell (uv)} , a price function is a function φ {\displaystyle \varphi } from the nodes of G {\displaystyle G} to the real numbers.
Flow distribution in manifolds Summary Flow_distribution_in_manifolds The relationship of pressure drop, flow rate and flow resistance is described as Q2 = ∆P/R. f = 64/Re for laminar flow where Re is the Reynolds number.
Cholesterol embolism Tissue diagnosis Cholesterol_embolism > Diagnosis > Tissue diagnosis The microscopic examination of tissue (histology) gives the definitive diagnosis. The diagnostic histopathologic finding is intravascular cholesterol crystals, which are seen as cholesterol clefts in routinely processed tissue (embedded in paraffin wax). The cholesterol crystals may be associated with macrophages, including giant cells, and eosinophils.The sensitivity of small core biopsies is modest, due to sampling error, as the process is often patchy.
Molecular modification The position of the water solubilizing group Structural_modification > Modification for water solubility > The position of the water solubilizing group In order to preserve the type of activity exhibited by the lead compound, the water solubilizing group should be attached to a part of the structure that is not involved in the drug–receptor interaction. Consequently, the route used to introduce a new water solubilizing group and its position in the lead structure will depend on the relative reactivities of the pharmacophore and the rest of the molecule. The reagents used to introduce the new water solubilizing group should be chosen on the basis that they do not react with, or in close proximity to, the pharmacophore. This will reduce the possibility of the new group affecting the relevant drug–receptor interactions.
Manfred Morari Summary Manfred_Morari in Chemical Engineering from the University of Minnesota in 1977. Dr. Morari held positions at the University of Wisconsin, Madison from 1977–1983, the California Institute of Technology from 1983-1991, and the Swiss Federal Institute of Technology in Zurich ETH Zurich. He is considered as pioneer in field of Model Predictive Control, Control of Hybrid Systems, Internal Model Control (IMC), and robust control.In recognition of his research contributions he received numerous awards, among them the Donald P. Eckman Award and the John R. Ragazzini Award of the Automatic Control Council, the Allan P. Colburn Award and the Professional Progress Award of the AIChE, the Curtis W. McGraw Research Award of the ASEE, Doctor Honoris Causa from Babes-Bolyai University, Fellow of IEEE and IFAC, and the IEEE Control Systems Field Award.
Hydrogen bacteria Sources of hydrogen Hydrogen_bacteria > Sources of hydrogen It can be coupled with O2, in oxidative respiration (2H2 + O2 → 2H2O), or with oxidized compounds, such as carbon dioxide or sulfate.In an ecosystem, hydrogen can be produced through abiotic and biological processes. The abiotic processes are mainly due to geothermal production and serpentinization.In geothermal processes, hydrogen is usually present as a gas and may be obtained by different reactions: 1. Water may react with the silicon radical at high temperature: Si· + H2O → SiOH + H· H· + H· → H22.
Word recognition Role of technology Word_recognition > Real world applications > Role of technology Improvements in technology have greatly contributed to advances in the understanding and research in word recognition. New word recognition capabilities have made computer-based learning programs more effective and reliable. Improved technology has enabled eye-tracking, which monitors individuals' saccadic eye movements while they read. This has furthered understanding of how certain patterns of eye movement increases word recognition and processing.
Telomerase RNA component Function Telomerase_RNA > Function Telomerase is a ribonucleoprotein polymerase that maintains telomere ends by addition of the telomere repeat TTAGGG. This repeat does vary across eukaryotes (see the table on the telomere article for a complete list). The enzyme consists of a protein component (TERT) with reverse transcriptase activity, and an RNA component, encoded by this gene, that serves as a template for the telomere repeat. CCCUAA found near position 50 of the vertebrate TERC sequence acts as the template.
History of calculus Legacy History_of_calculus > Newton and Leibniz > Legacy Today, both Newton and Leibniz are given credit for independently developing the basics of calculus. It is Leibniz, however, who is credited with giving the new discipline the name it is known by today: "calculus". Newton's name for it was "the science of fluents and fluxions".
Health risk assessment Limitations Health_risk_assessment > Limitations The limitations of a HRA are largely related to its usage and it is important to recognise that a HRA highlights health risks but does not diagnose disease and should not replace consultation with a medical or health practitioner.
Bogoliubov transformation Diagonalizing a quadratic Hamiltonian using matrix description Bogoliubov_transformation > Unified matrix description > Diagonalizing a quadratic Hamiltonian using matrix description Bogoliubov transformation lets us diagonalize a quadratic Hamiltonian H ^ = ( a † b † ) H ( a b ) {\displaystyle {\hat {H}}={\begin{pmatrix}a^{\dagger }&b^{\dagger }\end{pmatrix}}H{\begin{pmatrix}a\\b\end{pmatrix}}} by just diagonalizing the matrix Γ ± H {\displaystyle \Gamma _{\pm }H} . In the notations above, it is important to distinguish the operator H ^ {\displaystyle {\hat {H}}} and the numeric matrix H {\displaystyle H} . This fact can be seen by rewriting H ^ {\displaystyle {\hat {H}}} as H ^ = ( α † β † ) Γ ± U ( Γ ± H ) U − 1 ( α β ) {\displaystyle {\hat {H}}={\begin{pmatrix}\alpha ^{\dagger }&\beta ^{\dagger }\end{pmatrix}}\Gamma _{\pm }U(\Gamma _{\pm }H)U^{-1}{\begin{pmatrix}\alpha \\\beta \end{pmatrix}}} and Γ ± U ( Γ ± H ) U − 1 = D {\displaystyle \Gamma _{\pm }U(\Gamma _{\pm }H)U^{-1}=D} if and only if U {\displaystyle U} diagonalizes Γ ± H {\displaystyle \Gamma _{\pm }H} , i.e. U ( Γ ± H ) U − 1 = Γ ± D {\displaystyle U(\Gamma _{\pm }H)U^{-1}=\Gamma _{\pm }D} . Useful properties of Bogoliubov transformations are listed below.
Positive feedback Terminology Positive_feedback > Terminology Black had trouble convincing others of the utility of his invention in part because confusion existed over basic matters of definition. ": 121 These confusions, along with the everyday associations of positive with 'good' and negative with 'bad', have led many systems theorists to propose alternative terms. For example, Donella Meadows prefers the terms 'Reinforcing' and 'Balancing' feedbacks.
Refractory metals Advantages and shortfalls Refractory_metal > Advantages and shortfalls The high-temperature creep strain of alloys must be limited for them to be used. The creep strain should not exceed 1–2%. An additional complication in studying creep behavior of the refractory metals is interactions with environment, which can significantly influence the creep behavior.
Key strengthening Strength and time Key_strengthening > Strength and time CPU-bound hash functions are still vulnerable to hardware implementations. Such implementations of SHA-1 exist using as few as 5,000 gates, and 400 clock cycles. With multi-million gate FPGAs costing less than $100, an attacker can build a fully unrolled hardware cracker for about $5,000.
Internet Layer Relation to OSI model Internet_Layer > Relation to OSI model Because the internet layer of the TCP/IP model is easily compared directly with the network layer (layer 3) in the Open Systems Interconnection (OSI) protocol stack, the internet layer is often improperly called network layer.
Periodic properties The nucleus and its surrounding electrons Periodic_Table > Atomic structures of the elements > The nucleus and its surrounding electrons Two more, thorium and uranium, have isotopes undergoing radioactive decay with a half-life comparable to the age of the Earth. The stable elements plus bismuth, thorium, and uranium make up the 83 primordial elements that survived from the Earth's formation. The remaining eleven natural elements decay quickly enough that their continued trace occurrence rests primarily on being constantly regenerated as intermediate products of the decay of thorium and uranium. All 24 known artificial elements are radioactive.
Gene signature Summary Gene_signature A gene signature or gene expression signature is a single or combined group of genes in a cell with a uniquely characteristic pattern of gene expression that occurs as a result of an altered or unaltered biological process or pathogenic medical condition. This is not to be confused with the concept of gene expression profiling. Activating pathways in a regular physiological process or a physiological response to a stimulus results in a cascade of signal transduction and interactions that elicit altered levels of gene expression, which is classified as the gene signature of that physiological process or response.
Hemorrhagic shock Differential diagnosis Hemorrhagic_shock > Diagnosis > Differential diagnosis While hemorrhage is the most common cause of shock in the trauma patient, other causes of shock are to remain on the differential. Obstructive shock can occur in the setting of tension pneumothorax and cardiac tamponade. These etiologies should be uncovered in the primary survey. In the setting of head or neck trauma, an inadequate sympathetic response, or neurogenic shock, is a type of distributive shock that is caused by a decrease in peripheral vascular resistance.
Thyrotoxic hypokalaemic periodic paralysis Mechanism Thyrotoxic_periodic_paralysis > Mechanism For instance, increased carbohydrate intake leads to increased insulin levels; this is known to activate Na+/K+-ATPase. Once the precipitant is removed, the enzyme activity returns to normal levels. It has been postulated that male hormones increase Na+/K+-ATPase activity, and that this explains why males are at a higher risk of TPP despite thyroid disease being more common in females.TPP is regarded as a model for related conditions, known as "channelopathies", which have been linked with mutations in ion channels; the majority of these conditions occurs episodically.
Star schema Dimension tables Star_schema > Model > Dimension tables Dimension tables usually have a relatively small number of records compared to fact tables, but each record may have a very large number of attributes to describe the fact data. Dimensions can define a wide variety of characteristics, but some of the most common attributes defined by dimension tables include: Time dimension tables describe time at the lowest level of time granularity for which events are recorded in the star schema Geography dimension tables describe location data, such as country, state, or city Product dimension tables describe products Employee dimension tables describe employees, such as sales people Range dimension tables describe ranges of time, dollar values or other measurable quantities to simplify reportingDimension tables are generally assigned a surrogate primary key, usually a single-column integer data type, mapped to the combination of dimension attributes that form the natural key.
Viral marketing Metrics Viral_marketing > Methods and metrics > Metrics There are numerous indicators that can be used in this context as a function of marketers' objectives. Some of them include the most known online and social media statistics such as number and quality of shares, views, product reviews, and comments.
Resource sustainability Environmental and economic dimensions Ecological_sustainability > Interactions between dimensions > Environmental and economic dimensions Biodiversity, along with pollination and fertile soils, are examples. Others are clean air, clean water, and regulation of climate systems. Weak sustainability has come under criticism.
Archimedes constant Polygon approximation era Archimedes'_constant > History > Polygon approximation era Italian author Dante apparently employed the value 3 + 2 10 ≈ 3.14142 {\textstyle 3+{\frac {\sqrt {2}}{10}}\approx 3.14142} .The Persian astronomer Jamshīd al-Kāshī produced nine sexagesimal digits, roughly the equivalent of 16 decimal digits, in 1424, using a polygon with 3 × 2 28 {\textstyle 3\times 2^{28}} sides, which stood as the world record for about 180 years. French mathematician François Viète in 1579 achieved nine digits with a polygon of 3 × 2 17 {\textstyle 3\times 2^{17}} sides. Flemish mathematician Adriaan van Roomen arrived at 15 decimal places in 1593.
Bending strength Introduction Bending_strength > Introduction When an object is formed of a single material, like a wooden beam or a steel rod, is bent (Fig. 1), it experiences a range of stresses across its depth (Fig. 2). At the edge of the object on the inside of the bend (concave face) the stress will be at its maximum compressive stress value. At the outside of the bend (convex face) the stress will be at its maximum tensile value. These inner and outer edges of the beam or rod are known as the 'extreme fibers'. Most materials generally fail under tensile stress before they fail under compressive stress
Arterial blood gas Guidelines Arterial_blood_gas > Sampling and analysis > Guidelines A 1 mmHg change in PaCO2 above or below 40 mmHg results in 0.008 unit change in pH in the opposite direction. The PaCO2 will decrease by about 1 mmHg for every 1 mEq/L reduction in below 24 mEq/L A change in of 10 mEq/L will result in a change in pH of approximately 0.15 pH units in the same direction. Assess relation of pCO2 with pH: If pCO2 & pH are moving in opposite directions i.e., pCO2 ↑ when pH is <7.4 or pCO2 ↓ when pH > 7.4, it is a primary respiratory disorder. If pCO2 & pH are moving in same direction i.e., pCO2 ↑when pH is >7.4 or pCO2 ↓ when pH < 7.4, it is a primary metabolic disorder.
Dry land Resource depletion Dry_land > Environmental issues > Resource depletion Although humans have used land for its natural resources since ancient times, demand for resources such as timber, minerals, and energy has grown exponentially since the Industrial Revolution due to population growth. : 34 When a natural resource is depleted to the point of diminishing returns, it is considered the overexploitation of that resource. Some natural resources, such as timber, are considered renewable, because with sustainable practices they replenish to their previous levels. : 90 Fossil fuels such as coal are not considered renewable, as they take millions of years to form, with the current supply of coal expected to peak in the middle of the 21st century. : 90 Economic materialism, or consumerism, has influenced destructive patterns of modern resource usage, in contrast with pre-industrial usage.
Silencer (genetics) Summary Silencer_(genetics) With transcription blocked, the translation of RNA into proteins is impossible. Thus, silencers prevent genes from being expressed as proteins.RNA polymerase, a DNA-dependent enzyme, transcribes the DNA sequences, called nucleotides, in the 3' to 5' direction while the complementary RNA is synthesized in the 5' to 3' direction. RNA is similar to DNA, except that RNA contains uracil, instead of thymine, which forms a base pair with adenine.
Human anatomy Physiology Human_Physiology > Physiology These interact to maintain homeostasis, keeping the body in a stable state with safe levels of substances such as sugar and oxygen in the blood.Each system contributes to homeostasis, of itself, other systems, and the entire body. Some combined systems are referred to by joint names. For example, the nervous system and the endocrine system operate together as the neuroendocrine system.
Data dimension Summary Dimension_table A dimension is a structure that categorizes facts and measures in order to enable users to answer business questions. Commonly used dimensions are people, products, place and time. (Note: People and time sometimes are not modeled as dimensions.) In a data warehouse, dimensions provide structured labeling information to otherwise unordered numeric measures.
Multidimensional empirical mode decomposition Principal component analysis (PCA) or empirical orthogonal function analysis (EOF) Multidimensional_empirical_mode_decomposition > Ensemble empirical mode decomposition > Multi-dimensional ensemble empirical mode decomposition. > Principal component analysis (PCA) or empirical orthogonal function analysis (EOF) North et al. (Mon. Wea.
Software Assurance Techniques Software_Assurance > Techniques Software testing and verification are techniques used to identify and address defects and vulnerabilities in software code. There are several types of testing and verification techniques, including functional testing, performance testing, and security testing. Machine learning is increasingly used in software assurance to detect software problems.
Johannes Kepler Works Johannes_Kepler > Works 1993. Paperback ISBN 3-406-01639-1. Vol.
Glossary of artificial intelligence A Glossary_of_artificial_intelligence > A action model learning An area of machine learning concerned with creation and modification of software agent's knowledge about effects and preconditions of the actions that can be executed within its environment. This knowledge is usually represented in logic-based action description language and used as the input for automated planners. action selection A way of characterizing the most basic problem of intelligent systems: what to do next.
Working Memory Localization in the brain Working_Memory > In the brain > Localization in the brain Evidence from decoding studying employing multi-voxel-pattern-analysis of fMRI data showed the content of visual working memory can be decoded from activity patterns in visual cortex, but not prefrontal cortex. This led to the suggestion that the maintenance function of visual working memory is performed by visual cortex while the role of the prefrontal cortex is in executive control over working memory though it has been pointed out that such comparisons do not take into account the base rate of decoding across different regions.A 2003 meta-analysis of 60 neuroimaging studies found left frontal cortex was involved in low-task demand verbal working memory and right frontal cortex for spatial working memory. Brodmann's areas (BAs) 6, 8, and 9, in the superior frontal cortex was involved when working memory must be continuously updated and when memory for temporal order had to be maintained.
Simulation of production systems Flight Simulation_of_production_systems > More examples of simulation > Flight Flight simulation is mainly used to train pilots outside of the aircraft. In comparison to training in flight, simulation-based training allows for practicing maneuvers or situations that may be impractical (or even dangerous) to perform in the aircraft while keeping the pilot and instructor in a relatively low-risk environment on the ground. For example, electrical system failures, instrument failures, hydraulic system failures, and even flight control failures can be simulated without risk to the crew or equipment.Instructors can also provide students with a higher concentration of training tasks in a given period of time than is usually possible in the aircraft. For example, conducting multiple instrument approaches in the actual aircraft may require significant time spent repositioning the aircraft, while in a simulation, as soon as one approach has been completed, the instructor can immediately reposition the simulated aircraft to a location from which the next approach can be begun.
Insulin-like growth factor IGF receptors Insulin_growth_factor > IGF receptors The IGFs are known to bind the IGF-1 receptor, the insulin receptor, the IGF-2 receptor, the insulin-related receptor and possibly other receptors. The IGF-1 receptor is the "physiological" receptor. IGF-1 binds to it at significantly higher affinity than it binds the insulin receptor. Like the insulin receptor, the IGF-1 receptor is a receptor tyrosine kinase—meaning the receptor signals by causing the addition of a phosphate molecule on particular tyrosines. The IGF-2 receptor only binds IGF-2 and acts as a "clearance receptor"—it activates no intracellular signaling pathways, functioning only as an IGF-2 sequestering agent and preventing IGF-2 signaling.
Object-relational impedance mismatch SQL-Specific Impedance and Workarounds Object-relational_impedance_mismatch > Contention > SQL-Specific Impedance and Workarounds OO code (Java and .NET respectively) extend them and are invokeable in SQL as fluently as if built into the DBMS. Reusing library routines across multiple schemas is a supported modern paradigm. OO is in the backend because SQL will never get modern libraries and structures for today's programmers, despite the ISO SQL-99 committee wanting to add procedural.
Hopfield neural network Learning rules Hopfield_neural_network > Training > Learning rules There are various different learning rules that can be used to store information in the memory of the Hopfield network. It is desirable for a learning rule to have both of the following two properties: Local: A learning rule is local if each weight is updated using information available to neurons on either side of the connection that is associated with that particular weight. Incremental: New patterns can be learned without using information from the old patterns that have been also used for training.
Quantum Machine Learning Fully quantum machine learning Quantum_Machine_Learning > Machine learning with quantum computers > Fully quantum machine learning (This also relates to work on quantum pattern matching.) The problem of learning unitary transformations can be approached in a similar way.Going beyond the specific problem of learning states and transformations, the task of clustering also admits a fully quantum version, wherein both the oracle which returns the distance between data-points and the information processing device which runs the algorithm are quantum. Finally, a general framework spanning supervised, unsupervised and reinforcement learning in the fully quantum setting was introduced in, where it was also shown that the possibility of probing the environment in superpositions permits a quantum speedup in reinforcement learning. Such a speedup in the reinforcement-learning paradigm has been experimentally demonstrated in a photonic setup.
Programmed instruction The two main systems of programmed learning Programmed_instruction > Programmed learning arrives > The two main systems of programmed learning Crowder's system was to set multiple choice questions in the text, and provide feedback for each of the alternatives. Examples of this method show that the alternatives offered in questions were chosen to cover mistakes which students were likely to make. Crowder's system, which he called "intrinsic programming", was better known as "branching programming" on account of its multiple-choice alternatives.
Spherical mean Properties and uses Spherical_mean > Properties and uses From the continuity of u {\displaystyle u} it follows that the function is continuous, and that its limit as r → 0 {\displaystyle r\to 0} is u ( x ) . {\displaystyle u(x).} Spherical means can be used to solve the Cauchy problem for the wave equation ∂ t 2 u = c 2 Δ u {\displaystyle \partial _{t}^{2}u=c^{2}\,\Delta u} in odd space dimension. The result, known as Kirchhoff's formula, is derived by using spherical means to reduce the wave equation in R n {\displaystyle \mathbb {R} ^{n}} (for odd n {\displaystyle n} ) to the wave equation in R {\displaystyle \mathbb {R} } , and then using d'Alembert's formula. The expression itself is presented in wave equation article. If U {\displaystyle U} is an open set in R n {\displaystyle \mathbb {R} ^{n}} and u {\displaystyle u} is a C2 function defined on U {\displaystyle U} , then u {\displaystyle u} is harmonic if and only if for all x {\displaystyle x} in U {\displaystyle U} and all r > 0 {\displaystyle r>0} such that the closed ball B ( x , r ) {\displaystyle B(x,r)} is contained in U {\displaystyle U} one has This result can be used to prove the maximum principle for harmonic functions.
OpenMP Clauses OpenMP > Core elements > Clauses lastprivate: like private except original value is updated after construct. reduction: a safe way of joining work from all threads after construct.Synchronization clauses critical: the enclosed code block will be executed by only one thread at a time, and not simultaneously executed by multiple threads. It is often used to protect shared data from race conditions.
Glossary of string theory P Glossary_of_string_theory > P Short for periodic, a boundary condition on strings (as opposed to A for antiperiodic). 3. Pseudoscalar (current) 4.

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