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Passive Solar Radiative heat transfer Passive_solar_building > Passive solar heat transfer principles > Radiative heat transfer The main source of heat transfer is radiant energy, and the primary source is the sun. Solar radiation occurs predominantly through the roof and windows (but also through walls). Thermal radiation moves from a warmer surface to a cooler one. Roofs receive the majority of the solar radiation delivered to a house.
Fixed-point space Summary Fixed-point_space In mathematics, a Hausdorff space X is called a fixed-point space if every continuous function f: X → X {\displaystyle f:X\rightarrow X} has a fixed point. For example, any closed interval in R {\displaystyle \mathbb {R} } is a fixed point space, and it can be proved from the intermediate value property of real continuous function. The open interval (a, b), however, is not a fixed point space.
Limbic system Etymology and history Limbic_system > History > Etymology and history In addition to identifying the limbic system, he hypothesized a supposedly more primitive brain called the R-complex, related to reptiles, which controls basic functions like muscle movement and breathing. According to him, the third part, the neocortex, controls speech and reasoning and is the most recent evolutionary arrival. The concept of the limbic system has since been further expanded and developed by Walle Nauta, Lennart Heimer, and others.
Financial investment Momentum investing Capital_investments > Investment strategies > Momentum investing Momentum investors generally seek to buy stocks that are currently experiencing a short-term uptrend, and they usually sell them once this momentum starts to decrease. Stocks or securities purchased for momentum investing are often characterized by demonstrating consistently high returns for the past three to twelve months. However, in a bear market, momentum investing also involves short-selling securities of stocks that are experiencing a downward trend, because it is believed that these stocks will continue to decrease in value.
Serre spectral sequence Cohomology spectral sequence Serre_spectral_sequence > Cohomology spectral sequence Strictly speaking, what is meant is cohomology with respect to the local coefficient system on B given by the cohomology of the various fibers. Assuming for example, that B is simply connected, this collapses to the usual cohomology. For a path connected base, all the different fibers are homotopy equivalent.
Resuscitator History Resuscitator > History Once the unit reached this limit, it ceased to pump oxygen. For patients with chronic obstructive pulmonary disease (COPD), or any form of obstructive lung disease, the delivered pressure was insufficient pressure to fill the lungs with oxygen, meaning that, for patients with any sort of obstructive lung disease, units that pressure cycled did more harm than good.
Kelvin temperature Diffusion of thermal energy: black-body radiation Absolute_Temperature > Relationship of temperature, motions, conduction, and thermal energy > Diffusion of thermal energy: black-body radiation In any bulk quantity of a substance at equilibrium, black-body photons are emitted across a range of wavelengths in a spectrum that has a bell curve-like shape called a Planck curve (see graph in Fig. 5 at right). The top of a Planck curve (the peak emittance wavelength) is located in a particular part of the electromagnetic spectrum depending on the temperature of the black-body. Substances at extreme cryogenic temperatures emit at long radio wavelengths whereas extremely hot temperatures produce short gamma rays (see Table of common temperatures).
Gimbal Gimbal lock Gimbal > Gimbal lock Gimbal lock is the loss of one degree of freedom in a three-dimensional, three-gimbal mechanism that occurs when the axes of two of the three gimbals are driven into a parallel configuration, "locking" the system into rotation in a degenerate two-dimensional space. The word lock is misleading: no gimbal is restrained. All three gimbals can still rotate freely about their respective axes of suspension. Nevertheless, because of the parallel orientation of two of the gimbals' axes there is no gimbal available to accommodate rotation about one axis.
Metaphase I In life cycles Anaphase_I > Occurrence > In life cycles Meiosis occurs in eukaryotic life cycles involving sexual reproduction, consisting of the constant cyclical process of meiosis and fertilization. This takes place alongside normal mitotic cell division. In multicellular organisms, there is an intermediary step between the diploid and haploid transition where the organism grows.
Generalized network Example Network_flow_(function) > Example In Figure 3 you see the residual network for the given flow. Notice how there is positive residual capacity on some edges where the original capacity is zero in Figure 1, for example for the edge ( d , c ) {\displaystyle (d,c)} .
Lactate shuttle hypothesis Redox signaling Lactate_shuttle > Lactate as a signaling molecule: ‘lactormone’ > Redox signaling As illustrated by the peroxisomal intracellular lactate shuttle described above, the interconversion of lactate and pyruvate between cellular compartments plays a key role in the oxidative state of the cell. Specifically, the interconversion of NAD+ and NADH between compartments has been hypothesized to occur in the mitochondria. However, the evidence for this is lacking, as both lactate and pyruvate are quickly metabolized inside the mitochondria. However, the existence of the peroxisomal lactate shuttle suggests that this redox shuttle could exist for other organelles.
Flyback transformer Operation and usage Flyback_transformer > Operation and usage The pulse train coming from the flyback transformer windings is converted to direct current by a simple half-wave rectifier. There is no point in using a full wave design as there are no corresponding pulses of opposite polarity. One turn of a winding often produces pulses of several volts.
Fire hydrants Signage Fire_hydrant > Signage These are almost always coupled with a secondary form of signage. Hydrant Marker Plates – Found on power poles, fences, or street-signs, these are a comprehensive and effective system of identification.
Feature recognition Technology Feature_recognition > Technology Work on features (generally called feature technology) can be divided into two rough categories: Design-by-features and Feature recognition. In design-by-features, also known as feature-based design (FBD), feature structures are introduced directly into a model using particular operations or by sewing in shapes. On the other hand, the goal of feature recognition (FR) is to algorithmically extract higher level entities (e.g. manufacturing features) from lower level elements (e.g. surfaces, edges, etc.) of a CAD model.
Peter R. Holland Summary Peter_R._Holland This is a considerable conceptual advantage in understanding quantum motion and is potentially a computational benefit too. Another difference with Feynman is that, while the trajectories do the job of evolving the quantum system in time, the initial wavefunction is integral to the trajectory dynamical equations, as it provides the initial density and the initial velocity. Using Riemannian geometry Holland formulated this method in very general terms that include as special cases quantum many-particle systems and spin. He has applied it to other field theories, such as electromagnetism and second-order wave equations. Holland has published many peer-reviewed articles on the foundations of physics including the quantum potential, quantum hydrodynamics, quantum field theory, symmetries, hidden-variables theories, quantum back-reaction, quantum Hamilton-Jacobi theory, classical-like quantum systems, and the history of physics.
Proton-pump inhibitor Other Proton-pump_inhibitor > Adverse effects > Other Associations have been shown between PPI use and an increased risk of pneumonia, particularly in the 30 days after starting therapy, where it was found to be 50% higher in community use. Other very weak associations of PPI use have been found, such as with chronic kidney disease, dementia and HCC.As of 2016, results were derived from observational studies, it remained uncertain whether such associations were causal relationships.
Cause and effect Contrasted with conditionals Causal_relationships > Concept > Contrasted with conditionals But the sentence: If Shakespeare of Stratford-on-Avon did not write Macbeth, then someone else did.intuitively seems to be true, even though there is no straightforward causal relation in this hypothetical situation between Shakespeare's not writing Macbeth and someone else's actually writing it. Another sort of conditional, the counterfactual conditional, has a stronger connection with causality, yet even counterfactual statements are not all examples of causality. Consider the following two statements: If A were a triangle, then A would have three sides.
Resonant inductive coupling Overview Resonant_inductive_coupling > Mechanism details > Overview This process occurs in a resonant transformer, an electrical component which transformer consists of high Q coil wound on the same core with a capacitor connected across a coil to make a coupled LC circuit. The most basic resonant inductive coupling consists of one drive coil on the primary side and one resonance circuit on the secondary side. In this case, when the resonant state on the secondary side is observed from the primary side, two resonances as a pair are observed. One of them is called the antiresonant frequency (parallel resonant frequency 1), and the other is called the resonant frequency (serial resonant frequency 1').
Molar heat capacity Definition Molar_heat_capacity > Definition Paraffin wax, for example, has a specific heat of about 2500 J⋅K−1⋅kg−1 but a molar heat capacity of about 600 J⋅K−1⋅mol−1. The molar heat capacity is an "intensive" property of a substance, an intrinsic characteristic that does not depend on the size or shape of the amount in consideration. (The qualifier "specific" in front of an extensive property often indicates an intensive property derived from it.)
Homonym (biology) Hemihomonyms Junior_homonym > Hemihomonyms Both codes only consider taxa that are in their respective scope (animals for the ICZN; primarily plants for the ICN). Therefore, if an animal taxon has the same name as a plant taxon, both names are valid. Such names are called hemihomonyms.
Lt. Kernal Summary Lt._Kernal Lt. Kernal is a SCSI hard drive subsystem developed for the 8-bit Commodore 64 and Commodore 128 home computers. The Lt. Kernal is capable of a data transfer rate of more than 38 kilobytes per second and 65 kilobytes per second in Commodore 128 fast mode.
Vernier scale Zero error Vernier_scale > Functioning > Zero error Zero error is defined as the condition where a measuring instrument registers a reading when there should not be any reading. In case of vernier calipers it occurs when a zero on main scale does not coincide with a zero on vernier scale. The zero error may be of two types: when the scale is towards numbers greater than zero, it is positive; otherwise it is negative. The method to use a vernier scale or caliper with zero error is to use the formula actual reading = main scale + vernier scale − (zero error).Zero error may arise due to knocks or other damage which causes the 0.00 mm marks to be misaligned when the jaws are perfectly closed or just touching each other.
In vitro maturation Background In_vitro_maturation > Background A secondary follicle is formed with a few granulosa cell layers, as well as a theca layer. Finally before ovulation, a tertiary follicle is formed containing a follicular-fluid filled antrum. Of these small antral follicles, 1 will become dominant and ovulate (in monoovulatory species).
Digest access authentication Alternative authentication protocols Digest_authentication > HTTP digest authentication considerations > Alternative authentication protocols Some strong authentication protocols for web-based applications that are occasionally used include: Public key authentication (usually implemented with a HTTPS / SSL client certificate) using a client certificate. Kerberos or SPNEGO authentication, employed for example by Microsoft IIS running configured for Integrated Windows Authentication (IWA). Secure Remote Password protocol (preferably within the HTTPS / TLS layer). However, this is not implemented by any mainstream browsers. JSON Web Token (JWT) is a JSON-based standard RFC 7519 for creating access tokens that assert some number of claims.
Curse of dimensionality Machine learning Curse_of_dimensionality > Domains > Machine learning In other words, both the size of additional features and their (relative) cumulative discriminatory effect are important in observing a decrease or increase in the average predictive power. In metric learning, higher dimensions can sometimes allow a model to achieve better performance. After normalizing embeddings to the surface of a hypersphere, FaceNet achieves the best performance using 128 dimensions as opposed to 64, 256 and 512 dimensions in the authors' ablation study. A loss function for unitary-invariant dissimilarity between word embeddings was found to be minimized in high dimensions.
Power harvesting Energy sources Power_harvesting > Energy sources These can be utilized to capture mWs of energy from industrial equipment, structures, and even the human body. They are typically coupled with heat sinks to improve temperature gradient. Micro wind turbines are used to harvest kinetic energy readily available in the environment in the form of wind to fuel low-power electronic devices such as wireless sensor nodes.
Joel H. Ferziger Summary Joel_H._Ferziger Joel Henry Ferziger (24 March 1937 – 16 August 2004) was a Professor Emeritus of mechanical engineering at the Stanford University, Palo Alto, California, United States. Ferziger was an internationally recognized authority in fluid mechanics. His main area of research was computational fluid dynamics. He was known for developing computer simulations to model complex turbulent flows.Along with Milovan Peric, he is the coauthor of a widely cited book on computational fluid dynamics titled Computational Methods for Fluid Dynamics.Ferziger received his bachelor's degree in chemical engineering from the Cooper Union in New York in 1957.
A Line (RTD) History A_Line_(RTD) > History The first electric multiple unit railcars were pulled along the route on April 3, 2015, commencing testing and commissioning of the line.Revenue service began on April 22, 2016.Since the A line's opening in April 2016, there have been operational issues with the crossing gates due to software problems, resulting in frequent delays. Crossing arms have been coming down too early and staying down too long, causing traffic backups. RTD is making progress correcting this, along with the use of traffic guards, earning the project a slot on Westword's 2016 Colorado Hall of Shame.
Open Core Protocol Summary Open_Core_Protocol OCP data transfer models range from simple request-grant handshaking through pipelined request-response to complex out-of-order operations. Legacy IP cores can be adapted to OCP, while new implementations may take advantage of advanced features: designers select only those features and signals encompassing a core's specific data, control and test configuration. The Open Core Protocol (OCP) is one of several FPGA processor interconnects used to connect soft FPGA peripherals to FPGA CPUs—both soft microprocessor and hard-macro processor. Other such interconnects include Advanced eXtensible Interface (AXI), Avalon, and the Wishbone bus. FPGA vendor Altera joined the Open Core Protocol International Partnership in 2010.
Feature learning Text Feature_learning > Self-supervised > Text Word2vec is a word embedding technique which learns to represent words through self-supervision over each word and its neighboring words in a sliding window across a large corpus of text. The model has two possible training schemes to produce word vector representations, one generative and one contrastive. The first is word prediction given each of the neighboring words as an input.
Egyptian Arabic language Regular verb, form I, fíʕil/yífʕal Egyptian_Arabic_language > Morphology > Verbs > Strong verbs > Regular verb, form I, fíʕil/yífʕal Example: fíhim/yífham "understand" Boldfaced forms fíhm-it and fíhm-u differ from the corresponding forms of katab (kátab-it and kátab-u due to vowel syncope). Note also the syncope in ána fhím-t "I understood".
Bibliography of biology Summary Bibliography_of_biology This bibliography of biology is a list of notable works, organized by subdiscipline, on the subject of biology.Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines. Subdisciplines of biology are recognized on the basis of the scale at which organisms are studied and the methods used to study them.
Gravity of Earth Summary Gravity_of_Earth The agreed upon value for standard gravity is 9.80665 m/s2 (32.1740 ft/s2) by definition. This quantity is denoted variously as gn, ge (though this sometimes means the normal gravity at the equator, 9.7803267715 m/s2 (32.087686258 ft/s2)), g0, or simply g (which is also used for the variable local value). The weight of an object on Earth's surface is the downwards force on that object, given by Newton's second law of motion, or F = m a (force = mass × acceleration). Gravitational acceleration contributes to the total gravity acceleration, but other factors, such as the rotation of Earth, also contribute, and, therefore, affect the weight of the object. Gravity does not normally include the gravitational pull of the Moon and Sun, which are accounted for in terms of tidal effects.
Laura Eisenstein Summary Laura_Eisenstein Laura B. Eisenstein (1942–1985) was a professor in the physics department at the University of Illinois until her early death. Eisenstein was known for her contributions to the understanding of light-energy transduction mechanisms in biological molecules and their higher order assemblies. She was an experimentalist and spectroscopist who was particularly well known for her contributions applying the techniques of x-ray absorption spectroscopy and time-resolved resonance Raman spectroscopy to the study of biomolecules. These studies indicated that phenomena such as quantum-mechanical tunnelling can be successfully investigated even in soft-matter systems like proteins.
Decidable set Properties Computable_set > Properties The image of a computable set under a total computable bijection is computable. (In general, the image of a computable set under a computable function is c.e., but possibly not computable). A is a computable set if and only if it is at level Δ 1 0 {\displaystyle \Delta _{1}^{0}} of the arithmetical hierarchy. A is a computable set if and only if it is either the range of a nondecreasing total computable function, or the empty set. The image of a computable set under a nondecreasing total computable function is computable.
Skin temperature (of an atmosphere) Background Skin_temperature_(of_an_atmosphere) > Background The uppermost opaque layer (the emission level) will thus radiate as a blackbody at the planet's equilibrium temperature.The skin layer of an atmosphere references a layer far above the emission level, at a height where the atmosphere is extremely diffuse. As a result, this thin layer is transparent to solar (visible) radiation and translucent to planetary/atmospheric (infrared) radiation. In other words, the skin layer acts as a graybody, because it is not a perfect absorber/emitter of infrared radiation. Instead, most of the infrared radiation coming from below (i.e. from the emission level) will pass through the skin layer, with only a small fraction being absorbed, resulting in a cold skin layer.
Epistasis and functional genomics Inferring function: alleviating and aggravating mutations Epistasis_and_functional_genomics > Inferring function: alleviating and aggravating mutations Aggravating mutations on the other hand give rise to a phenotype which is worse than the cumulative effect of each single mutation. This aggravated phenotype is indicative of two genes in compensatory pathways.
Name space Java Name_space > In programming languages > Computer-science considerations > Use in common languages > Java In Java, the idea of a namespace is embodied in Java packages. All code belongs to a package, although that package need not be explicitly named. Code from other packages is accessed by prefixing the package name before the appropriate identifier, for example class String in package java.lang can be referred to as java.lang.String (this is known as the fully qualified class name). Like C++, Java offers a construct that makes it unnecessary to type the package name (import).
Deutsch–Jozsa algorithm Summary Deutsch_algorithm The Deutsch–Jozsa algorithm is a deterministic quantum algorithm proposed by David Deutsch and Richard Jozsa in 1992 with improvements by Richard Cleve, Artur Ekert, Chiara Macchiavello, and Michele Mosca in 1998. Although of little practical use, it is one of the first examples of a quantum algorithm that is exponentially faster than any possible deterministic classical algorithm.The Deutsch–Jozsa problem is specifically designed to be easy for a quantum algorithm and hard for any deterministic classical algorithm. It is a black box problem that can be solved efficiently by a quantum computer with no error, whereas a deterministic classical computer would need a exponential number of queries to the black box to solve the problem. More formally, it yields an oracle relative to which EQP, the class of problems that can be solved exactly in polynomial time on a quantum computer, and P are different.Since the problem is easy to solve on a probabilistic classical computer, it does not yield an oracle separation with BPP, the class of problems that can be solved with bounded error in polynomial time on a probabilistic classical computer. Simon's problem is an example of a problem that yields an oracle separation between BQP and BPP.
Background selection Summary Background_selection Background selection describes the loss of genetic diversity at a non-deleterious locus due to negative selection against linked deleterious alleles. It is one form of linked selection, where the maintenance or removal of an allele from a population is dependent upon the alleles in its linkage group. The name emphasizes the fact that the genetic background, or genomic environment, of a neutral mutation has a significant impact on whether it will be preserved (genetic hitchhiking) or purged (background selection) from a population.
Pulmonary contusion Signs and symptoms Pulmonary_contusion > Signs and symptoms Presentation may be subtle; people with mild contusion may have no symptoms at all. However, pulmonary contusion is frequently associated with signs (objective indications) and symptoms (subjective states), including those indicative of the lung injury itself and of accompanying injuries. Because gas exchange is impaired, signs of low blood oxygen saturation, such as low concentrations of oxygen in arterial blood gas and cyanosis (bluish color of the skin and mucous membranes) are commonly associated. Dyspnea (painful breathing or difficulty breathing) is commonly seen, and tolerance for exercise may be lowered.
Comparison of TLS implementations Summary Comparison_of_TLS_implementations The Transport Layer Security (TLS) protocol provides the ability to secure communications across or inside networks. This comparison of TLS implementations compares several of the most notable libraries. There are several TLS implementations which are free software and open source. All comparison categories use the stable version of each implementation listed in the overview section. The comparison is limited to features that directly relate to the TLS protocol.
Data mining Summary Data_mining It also is a buzzword and is frequently applied to any form of large-scale data or information processing (collection, extraction, warehousing, analysis, and statistics) as well as any application of computer decision support system, including artificial intelligence (e.g., machine learning) and business intelligence. The book Data Mining: Practical Machine Learning Tools and Techniques with Java (which covers mostly machine learning material) was originally to be named Practical Machine Learning, and the term data mining was only added for marketing reasons. Often the more general terms (large scale) data analysis and analytics—or, when referring to actual methods, artificial intelligence and machine learning—are more appropriate.
Epidemiology Causal inference Epidemiological_study > Causal inference Although epidemiology is sometimes viewed as a collection of statistical tools used to elucidate the associations of exposures to health outcomes, a deeper understanding of this science is that of discovering causal relationships. "Correlation does not imply causation" is a common theme for much of the epidemiological literature. For epidemiologists, the key is in the term inference. Correlation, or at least association between two variables, is a necessary but not sufficient criterion for the inference that one variable causes the other.
Immunological memory Innate immune memory Immune_memory > Innate immune memory Innate immune memory (trained immunity) is defined as a long-term functional reprogramming of innate immune cells evoked by exogenous or endogenous insults and leading to an altered response towards a second challenge after returning to a non-activated state.When innate immune cells receive an activation signal; for example, through recognition of PAMPs with PRRs, they start the expression of proinflammatory genes, initiate an inflammatory response, and undergo epigenetic reprogramming. After the second stimulation, the transcription activation is faster and more robust. Immunological memory was reported in monocytes, macrophages, NK cells, ILC1, ILC2, and recently in ILC3 as well, Concomitantly, some nonimmune cells, for example, epithelial stem cells on barrier tissues, or fibroblasts, change their epigenetic state and respond differently after priming insult.
Electromagnetic wave equation Summary Electromagnetic_wave_equation In a vacuum, vph = c0 = 299792458 m/s, a fundamental physical constant. The electromagnetic wave equation derives from Maxwell's equations. In most older literature, B is called the magnetic flux density or magnetic induction. The following equationspredicate that any electromagnetic wave must be a transverse wave, where the electric field E and the magnetic field B are both perpendicular to the direction of wave propagation.
Binary coding Summary Binary_coding Those methods may use fixed-width or variable-width strings. In a fixed-width binary code, each letter, digit, or other character is represented by a bit string of the same length; that bit string, interpreted as a binary number, is usually displayed in code tables in octal, decimal or hexadecimal notation. There are many character sets and many character encodings for them. A bit string, interpreted as a binary number, can be translated into a decimal number. For example, the lower case a, if represented by the bit string 01100001 (as it is in the standard ASCII code), can also be represented as the decimal number "97".
History of compiler construction Context-free grammars and parsers History_of_compiler_construction > Context-free grammars and parsers A parser is an important component of a compiler. It parses the source code of a computer programming language to create some form of internal representation. Programming languages tend to be specified in terms of a context-free grammar because fast and efficient parsers can be written for them. Parsers can be written by hand or generated by a parser generator.
Bias of an estimator Bayesian view Unbiased_estimator > Bayesian view Most bayesians are rather unconcerned about unbiasedness (at least in the formal sampling-theory sense above) of their estimates. For example, Gelman and coauthors (1995) write: "From a Bayesian perspective, the principle of unbiasedness is reasonable in the limit of large samples, but otherwise it is potentially misleading. "Fundamentally, the difference between the Bayesian approach and the sampling-theory approach above is that in the sampling-theory approach the parameter is taken as fixed, and then probability distributions of a statistic are considered, based on the predicted sampling distribution of the data. For a Bayesian, however, it is the data which are known, and fixed, and it is the unknown parameter for which an attempt is made to construct a probability distribution, using Bayes' theorem: p ( θ ∣ D , I ) ∝ p ( θ ∣ I ) p ( D ∣ θ , I ) {\displaystyle p(\theta \mid D,I)\propto p(\theta \mid I)p(D\mid \theta ,I)} Here the second term, the likelihood of the data given the unknown parameter value θ, depends just on the data obtained and the modelling of the data generation process.
Nuclear computation Summary Nuclear_computation Nuclear computation is a type of computation which allows threads to either spawn new threads or converge many threads to one. The aim of nuclear computation is to take advantage of threading abilities of modern multi-core processors where the trend is to increase their hardware ability to compute more threads then their earlier generation processors.Nuclear computation focuses on real time processing for things like multimedia such as processing audio where a real time deadline (the sample rate in Hz) exists. For that reason it should not block and computational processes which alter shared memory must be atomic (executed in one clock cycle without locking). Nuclear computation allows a computational thread to use thread fission to turn one thread into many or thread fusion to turn many threads into one.
Stagnation point Summary Stagnation_point In fluid dynamics, a stagnation point is a point in a flow field where the local velocity of the fluid is zero. : § 3.2 A plentiful, albeit surprising, example of such points seem to appear in all but the most extreme cases of fluid dynamics in the form of the "no-slip condition"; the assumption that any portion of a flow field lying along some boundary consists of nothing but stagnation points (the question as to whether this assumption reflects reality or is simply a mathematical convenience has been a continuous subject of debate since the principle was first established). The Bernoulli equation shows that the static pressure is highest when the velocity is zero and hence static pressure is at its maximum value at stagnation points: in this case static pressure equals stagnation pressure. : § 3.5 The Bernoulli equation applicable to incompressible flow shows that the stagnation pressure is equal to the dynamic pressure plus static pressure.
Timeline of quantum computing and communication Summary Timeline_of_quantum_computing_and_communication This is a timeline of quantum computing.
Convective acceleration Summary Convective_acceleration The Navier–Stokes equations are useful because they describe the physics of many phenomena of scientific and engineering interest. They may be used to model the weather, ocean currents, water flow in a pipe and air flow around a wing. The Navier–Stokes equations, in their full and simplified forms, help with the design of aircraft and cars, the study of blood flow, the design of power stations, the analysis of pollution, and many other things.
Spur gears General Lantern_gear > Nomenclature > General {\displaystyle d_{w}={\frac {2a}{u+1}}={\frac {2a}{{\frac {z_{2}}{z_{1}}}+1}}.} Pitch surface In cylindrical gears, cylinder formed by projecting a pitch circle in the axial direction.
Pea protein Functional ingredient Pea_protein > Uses > Functional ingredient Pea protein is also used as a low-cost functional ingredient in food manufacturing to improve the nutritional value and texture of food products. They can also optimize the viscosity, emulsification, gelation, stability, or fat-binding properties of food. For example, the capacity of pea protein to form stable foams is a property in cakes, souffles, whipped toppings, and fudges.
M1 protein Summary M1_protein It is therefore required that M1 binds both membrane and RNA simultaneously.The M1 protein binds to the viral RNA. The binding is not specific to any RNA sequence, and is performed via a peptide sequence rich in basic amino acids.It also has multiple regulatory functions, performed by interaction with the components of the host cell. The mechanisms regulated include a role in the export of the viral ribonucleoproteins from the host cell nucleus, inhibition of viral transcription, and a role in the virus assembly and budding.
Priming (psychology) Focal cortical lesions Priming_(psychology) > Effects of brain injuries > Focal cortical lesions Patient J.P., who suffered a stroke in the left medial/temporal gyrus, resulting in auditory verbal agnosia - the inability to comprehend spoken words, but maintaining the ability to read and write, and with no effects to hearing ability. J.P. showed normal perceptual priming, but his conceptual priming ability for spoken words was, expectedly, impaired. Another patient, N.G., who suffered from prosopanomia (the inability to retrieve proper names) following damage to his left temporal lobe, was unable to spontaneously provide names of persons or cities, but was able to successfully complete a word-fragment completion exercise following priming with these names. This demonstrated intact perceptual priming abilities.
Doppler optical coherence tomography Phase-Resolved Doppler OCT Method Doppler_optical_coherence_tomography > Phase-Resolved Doppler OCT Method In each scan, the phase would be different. Phase-resolved Doppler OCT uses this phase change to develop flow velocity images, which can obtain both high imaging speed, high velocity sensitivity, and high spatial resolution. By calculating the phase change, the Doppler frequency shift f n {\displaystyle f_{n}} can be determined: f n = Δ Φ 2 π T ( 7 ) {\displaystyle f_{n}={\frac {\Delta \Phi }{2\pi T}}\qquad \quad (7)} The standard deviation of the Doppler spectrum is as follow: σ 2 = ∫ ( f − f D ) 2 ( P ( f ) ) d f ∫ ( P ( f ) ) d f ( 8 ) {\displaystyle \sigma ^{2}={\frac {\int (f-f_{D})^{2}(P\left(f\right))df}{\int (P\left(f\right))df}}\qquad \quad (8)} where P(f) is the Doppler power spectrum and f D {\displaystyle f_{D}} is the centroid value of the Doppler frequency shift.Changing flow velocity impacts the value of the standard deviation. When the difference in flow velocity becomes larger, the Doppler frequency spectrum becomes wider. As a result, the standard deviation becomes larger.
Glossary of probability and statistics I Glossary_of_probability_and_statistics > I independence independent variable interquartile range (IQR) Also midspread, middle 50%, and H-spread. A measure of the statistical dispersion or spread of a dataset, defined as the difference between the 25th and 75th percentiles of the data. To calculate the IQR, the dataset is divided into four rank-ordered even parts or quartiles, the boundaries between which, at the 25th, 50th, and 75th percentiles, are denoted Q {\displaystyle Q} 1, Q {\displaystyle Q} 2, and Q {\displaystyle Q} 3, respectively; the IQR = Q {\displaystyle Q} 3 − {\displaystyle -} Q {\displaystyle Q} 1.
Geometric sum Euclid of Alexandria (c.300 BC) Geometric_series > History > Euclid of Alexandria (c.300 BC) For example, the contemporary notation for geometric series (i.e., a + ar + ar2 + ar3 + ... + arn) does not label specific portions of terms that are equal to each other. Also in the cited introduction the editor comments, Most of the theorems appearing in the Elements were not discovered by Euclid himself, but were the work of earlier Greek mathematicians such as Pythagoras (and his school), Hippocrates of Chios, Theaetetus of Athens, and Eudoxus of Cnidos. However, Euclid is generally credited with arranging these theorems in a logical manner, so as to demonstrate (admittedly, not always with the rigour demanded by modern mathematics) that they necessarily follow from five simple axioms.
Biochemical Switches in the Cell Cycle Mitotic exit Biochemical_Switches_in_the_Cell_Cycle > Mitotic exit Mitotic exit is an important transition point that signifies the end of mitosis and the onset of new G1 phase for a cell, and the cell needs to rely on specific control mechanisms to ensure that once it exits mitosis, it never returns to mitosis until it has gone through G1, S, and G2 phases and passed all the necessary checkpoints. Many factors including cyclins, cyclin-dependent kinases (CDKs), ubiquitin ligases, inhibitors of cyclin-dependent kinases, and reversible phosphorylations regulate mitotic exit to ensure that cell cycle events occur in correct order with the fewest errors. The end of mitosis is characterized by spindle breakdown, shortened kinetochore microtubules, and pronounced outgrowth of astral (non-kinetochore) microtubules. For a normal eukaryotic cell, mitotic exit is irreversible.
Electronic feedback loops Education Feedback_loop > Applications > Education For feedback in the educational context, see corrective feedback.
Geological structure Stress-strain curve Structural_geologist > Characterization of the mechanical properties of rock > Stress-strain curve One mechanism of plastic deformation is the movement of dislocations by an applied stress. Because rocks are essentially aggregates of minerals, we can think of them as poly-crystalline materials. Dislocations are a type of crystallographic defect which consists of an extra or missing half plane of atoms in the periodic array of atoms that make up a crystal lattice. Dislocations are present in all real crystallographic materials.
Economics of car usage Private benefits Economics_of_car_use > Private benefits The benefits of using a car differ by many factors, in regard to location and culture. One general benefit is availability of use which, when coupled with public support via infrastructure (such as roads or fuel stations), can allow highly flexible movement and transportation. Because public transportations are not as well omnipresent and normally don't run at certain day periods, they might not be an option. Car allows a certain freedom of movement, that other means of transport do not. Another private benefit car owners enjoy, is comfort. The car allows the transportation of the driver (and passengers) from a certain point A, to another point B, within an acclimatized and protected interior.
Fourier Transform Infrared Spectroscopy Michelson interferometer Fourier_Transform_Infrared_Spectroscopy > Michelson interferometer In a Michelson interferometer adapted for FTIR, light from the polychromatic infrared source, approximately a black-body radiator, is collimated and directed to a beam splitter. Ideally 50% of the light is refracted towards the fixed mirror and 50% is transmitted towards the moving mirror. Light is reflected from the two mirrors back to the beam splitter and some fraction of the original light passes into the sample compartment. There, the light is focused on the sample.
Cavalieri's quadrature formula History Cavalieri's_quadrature_formula > History A detailed discussion of the history, with original sources, is given in (Laubenbacher & Pengelley 1998, Chapter 3, Analysis: Calculating Areas and Volumes); see also history of calculus and history of integration. The case of the parabola was proven in antiquity by the ancient Greek mathematician Archimedes in his The Quadrature of the Parabola (3rd century BC), via the method of exhaustion. Of note is that Archimedes computed the area inside a parabola – a so-called "parabolic segment" – rather than the area under the graph y = x2, which is instead the perspective of Cartesian geometry. These are equivalent computations, but reflect a difference in perspective.
Comparison of application virtualization software Comparison of virtual machines Comparison_of_application_virtualization_software > Comparison of virtual machines Any virtual machine which can be run can be interpreted, so the column designation here refers to whether the design includes provisions for efficient interpreting (for common usage). Just-in-time compilation (JIT), refers to a method of compiling to native instructions at the latest possible time, usually immediately before or during the running of the program. The challenge of JIT is more one of implementation than of virtual machine design, however, modern designs have begun to make considerations to help efficiency.
Thermoelectric materials Refrigeration Thermoelectric_figure_of_merit > Applications > Refrigeration Thermoelectric materials can be used as refrigerators, called "thermoelectric coolers", or "Peltier coolers" after the Peltier effect that controls their operation. As a refrigeration technology, Peltier cooling is far less common than vapor-compression refrigeration. The main advantages of a Peltier cooler (compared to a vapor-compression refrigerator) are its lack of moving parts or refrigerant, and its small size and flexible shape (form factor).The main disadvantage of Peltier coolers is low efficiency. It is estimated that materials with ZT>3 (about 20–30% Carnot efficiency) would be required to replace traditional coolers in most applications. Today, Peltier coolers are only used in niche applications, especially small scale, where efficiency is not important.
Space habitat Access to solar energy Space_habitat > Advantages > Access to solar energy Space has an abundance of light produced from the Sun. In Earth orbit, this amounts to 1400 watts of power per square meter. This energy can be used to produce electricity from solar cells or heat engine based power stations, process ores, provide light for plants to grow and to warm space habitats.
Wheelchair access Buildings Wheelchair_access > Mobility and access > Buildings For access to public buildings, it is frequently necessary to adapt older buildings with features such as ramps or elevators in order to allow access by wheelchair users and other people with mobility impairments. Other important adaptations can include powered doors, lowered fixtures such as sinks and water fountains, and accessible toilets with adequate space and grab bars to allow the disabled person to transfer out of their wheelchair onto the fixture. Access needs for people with other disabilities, for instance visual impairments, may also be required, such as by provision of high visibility markings on the edges of steps and braille labelling.
Hasse principle Summary Hasse_principle In mathematics, Helmut Hasse's local–global principle, also known as the Hasse principle, is the idea that one can find an integer solution to an equation by using the Chinese remainder theorem to piece together solutions modulo powers of each different prime number. This is handled by examining the equation in the completions of the rational numbers: the real numbers and the p-adic numbers. A more formal version of the Hasse principle states that certain types of equations have a rational solution if and only if they have a solution in the real numbers and in the p-adic numbers for each prime p.
Cholestatic hepatitis Mechanisms of drug-induced cholestasis Cholestatic_hepatitis > Mechanism > Mechanisms of drug-induced cholestasis However, hepatocytes have safety mechanisms that can compensate for impaired canalicular bile efflux. In response to cholestasis, MRP3 and MRP4 on the basolateral membrane are upregulated to allow efflux of accumulated bile salts into portal blood. Similarly, MRP2 can accommodate additional bile flow across the apical membrane in cholestatic conditions.
Alan Kostelecky Summary Alan_Kostelecky V. Alan Kostelecký is a theoretical physicist who is a distinguished professor of physics at Indiana University, Bloomington. He is noted for his work on Lorentz symmetry breaking in particle physics. He has been described as the world's leading authority on violations of space-time symmetry.Kostelecký was a student at the International School of Geneva, Switzerland (1965-1973). Subsequently, he began as an undergraduate in biology, switched his degree to chemistry, and eventually switched for the last time to physics and obtained his undergraduate degree in science from Bristol University in 1977, and his Ph.D.
Misuse of p-values Multiple comparisons problem Misuse_of_p-values > Multiple comparisons problem The multiple comparisons problem occurs when one considers a set of statistical inferences simultaneously or infers a subset of parameters selected based on the observed values. It is also known as the look-elsewhere effect. Errors in inference, including confidence intervals that fail to include their corresponding population parameters or hypothesis tests that incorrectly reject the null hypothesis, are more likely to occur when one considers the set as a whole.
Restricted Lorentz group Connected components Lorentz_group > Basic properties > Connected components Because it is a Lie group, the Lorentz group O ( 1 , 3 ) {\displaystyle {\text{O}}(1,3)} is both a group and admits a topological description as a smooth manifold. As a manifold, it has four connected components. Intuitively, this means that it consists of four topologically separated pieces.
Human chromosomes SNP frequency across the human genome Human_chromosomes > Genomic variation in humans > SNP frequency across the human genome Therefore, the SNP Consortium protocol was designed to identify SNPs with no bias towards coding regions and the Consortium's 100,000 SNPs generally reflect sequence diversity across the human chromosomes. The SNP Consortium aims to expand the number of SNPs identified across the genome to 300 000 by the end of the first quarter of 2001. Changes in non-coding sequence and synonymous changes in coding sequence are generally more common than non-synonymous changes, reflecting greater selective pressure reducing diversity at positions dictating amino acid identity. Transitional changes are more common than transversions, with CpG dinucleotides showing the highest mutation rate, presumably due to deamination.
Optician Automated Lensmeter Optician > Equipment > Automated Lensmeter An automated lensmeter uses the reflected wavelength of green light off of the lens surface along every lens meridian in order to determine all of the data points that the optician interprets with the manual lensometer. The benefits of an automated lensmeter are increased speed, adjustments for variables in the index of refraction in the lens material, the ability to measure UV and light transmittance, and a decrease in training time while on the job. The drawbacks of automated lensmeters in comparison to manual lensmeters are greater difficulty identifying higher prismatic errors, aberrations, and surfacing power errors (optic waves), and the necessity of the optician not to tip the lens to avoid an erroneous result.
Development of the nervous system in humans Early life stress Development_of_the_nervous_system_in_humans > Research > Early life stress Receptor type is another consideration when determining whether or not a brain region is sensitive to the effects of early life stress. Brain regions with a high density of glucocorticoid receptors are especially vulnerable to the effects of early life stress, likely because glucocorticoids bind to these receptors during stress exposure, facilitating the development of survival responses at the cost of other important neural pathways. Some examples of brain regions with high glucocorticoid receptor density are the hippocampus and cerebellar vermis.
Infinite-dimensional vector function Crinkled arcs Infinite-dimensional_vector_function > Integral and derivative > Crinkled arcs If {\displaystyle } is an interval contained in the domain of a curve f {\displaystyle f} that is valued in a topological vector space then the vector f ( b ) − f ( a ) {\displaystyle f(b)-f(a)} is called the chord of f {\displaystyle f} determined by {\displaystyle } . If {\displaystyle } is another interval in its domain then the two chords are said to be non−overlapping chords if {\displaystyle } and {\displaystyle } have at most one end−point in common. Intuitively, two non−overlapping chords of a curve valued in an inner product space are orthogonal vectors if the curve makes a right angle turn somewhere along its path between its starting point and its ending point. If every pair of non−overlapping chords are orthogonal then such a right turn happens at every point of the curve; such a curve can not be differentiable at any point.
Hilbert transforms History Hilbert_transforms > History The Hilbert transform was a motivating example for Antoni Zygmund and Alberto Calderón during their study of singular integrals. Their investigations have played a fundamental role in modern harmonic analysis. Various generalizations of the Hilbert transform, such as the bilinear and trilinear Hilbert transforms are still active areas of research today.
Eye pattern Source data Eye_Diagram > Calculation > Source data The first step of computing an eye pattern is normally to obtain the waveform being analyzed in a quantized form. This may be done by measuring an actual electrical system with an oscilloscope of sufficient bandwidth, or by creating synthetic data with a circuit simulator in order to evaluate the signal integrity of a proposed design. A combination of the two approaches may be used as well: simulating the effects of an arbitrary circuit or transmission line on a measured signal, perhaps to determine whether a signal will still be intelligible after passing through a long cable. Interpolation may also be applied at this time in order to increase the number of samples per unit interval (UI) and produce a smooth, gap-free plot which is more visually appealing and easier to understand.
Homology (biology) Summary Homologous_structure Significant similarity is strong evidence that two sequences are related by divergent evolution from a common ancestor. Alignments of multiple sequences are used to discover the homologous regions. Homology remains controversial in animal behaviour, but there is suggestive evidence that, for example, dominance hierarchies are homologous across the primates.
Stiffness method Summary Stiffness_method The direct stiffness method originated in the field of aerospace. Researchers looked at various approaches for analysis of complex airplane frames. These included elasticity theory, energy principles in structural mechanics, flexibility method and matrix stiffness method. It was through analysis of these methods that the direct stiffness method emerged as an efficient method ideally suited for computer implementation.
Subtraction Notation and terminology Subtraction > Notation and terminology "Subtraction" is an English word derived from the Latin verb subtrahere, which in turn is a compound of sub "from under" and trahere "to pull". Thus, to subtract is to draw from below, or to take away. Using the gerundive suffix -nd results in "subtrahend", "thing to be subtracted". Likewise, from minuere "to reduce or diminish", one gets "minuend", which means "thing to be diminished".
Asymptotically optimal algorithm Summary Asymptotic_optimality On modern computers, hardware optimizations such as memory cache and parallel processing may be "broken" by an asymptotically optimal algorithm (assuming the analysis did not take these hardware optimizations into account). In this case, there could be sub-optimal algorithms that make better use of these features and outperform an optimal algorithm on realistic data.An example of an asymptotically optimal algorithm not used in practice is Bernard Chazelle's linear-time algorithm for triangulation of a simple polygon. Another is the resizable array data structure published in "Resizable Arrays in Optimal Time and Space", which can index in constant time but on many machines carries a heavy practical penalty compared to ordinary array indexing.
ABX testing Summary ABX_test An ABX test is a method of comparing two choices of sensory stimuli to identify detectable differences between them. A subject is presented with two known samples (sample A, the first reference, and sample B, the second reference) followed by one unknown sample X that is randomly selected from either A or B. The subject is then required to identify X as either A or B. If X cannot be identified reliably with a low p-value in a predetermined number of trials, then the null hypothesis cannot be rejected and it cannot be proven that there is a perceptible difference between A and B. ABX tests can easily be performed as double-blind trials, eliminating any possible unconscious influence from the researcher or the test supervisor. Because samples A and B are provided just prior to sample X, the difference does not have to be discerned from assumption based on long-term memory or past experience. Thus, the ABX test answers whether or not, under the test circumstances, a perceptual difference can be found.
Wedge pattern Rising wedge Wedge_pattern > Rising wedge Although both lines point in the same direction, the lower line rises at a steeper angle than the upper one. Prices usually decline after breaking through the lower boundary line.
Theory of algorithms Computational complexity theory Computational_theorist > Branches > Computational complexity theory So in our previous example, we might say that the problem requires O ( n ) {\displaystyle O(n)} steps to solve. Perhaps the most important open problem in all of computer science is the question of whether a certain broad class of problems denoted NP can be solved efficiently. This is discussed further at Complexity classes P and NP, and P versus NP problem is one of the seven Millennium Prize Problems stated by the Clay Mathematics Institute in 2000. The Official Problem Description was given by Turing Award winner Stephen Cook.
Gene nomenclature Summary Gene_nomenclature Gene nomenclature is the scientific naming of genes, the units of heredity in living organisms. It is also closely associated with protein nomenclature, as genes and the proteins they code for usually have similar nomenclature. An international committee published recommendations for genetic symbols and nomenclature in 1957. The need to develop formal guidelines for human gene names and symbols was recognized in the 1960s and full guidelines were issued in 1979 (Edinburgh Human Genome Meeting).
Illusory correlation Working-memory capacity Illusory_correlation > Theories > Working-memory capacity In an experimental study done by Eder, Fiedler and Hamm-Eder (2011), the effects of working-memory capacity on illusory correlations were investigated. They first looked at the individual differences in working memory, and then looked to see if that had any effect on the formation of illusory correlations. They found that individuals with higher working memory capacity viewed minority group members more positively than individuals with lower working memory capacity. In a second experiment, the authors looked into the effects of memory load in working memory on illusory correlations.
Biological virus Vaccines Viral_particle > Role in human disease > Prevention and treatment > Vaccines Vaccination is a cheap and effective way of preventing infections by viruses. Vaccines were used to prevent viral infections long before the discovery of the actual viruses. Their use has resulted in a dramatic decline in morbidity (illness) and mortality (death) associated with viral infections such as polio, measles, mumps and rubella. Smallpox infections have been eradicated.
Sepiapterin reductase deficiency Levodopa and Carbidopa Sepiapterin_reductase_deficiency > Treatment > Levodopa and Carbidopa Levodopa is in a class of medications called central nervous system agents where its main function is to become dopamine in the brain. Carbidopa is in a class of medications called decarboxylase inhibitors and it works by preventing levodopa from being broken down before it reaches the brain. This treatment is effective in mitigating motor symptoms, but it does not totally eradicate them and it is not as effective on cognitive problems. Patients who have been diagnosed with SR deficiency and have undergone this treatment have shown improvements with most motor impairments including oculogyric crises, dystonia, balance, and coordination.
Joseph L. Ullman Selected works Joseph_L._Ullman > Selected works Soc. 107 (2): 291–299. doi:10.1090/s0002-9947-1963-0147817-0.
Dynamic Delegation Discovery System Summary Dynamic_Delegation_Discovery_System DDDS defines a mechanism for using the Domain Name System (DNS) as the database for arbitrary identifier schemes. The primary logical DNS container used to hold DDDS information is the NAPTR record. DDDS is defined in RFC 3401, RFC 3402, RFC 3403, RFC 3404, and RFC 3405.
Social simulator Criticisms Social_simulator > Criticisms Since its creation, computerized social simulation has been the target of some criticism in regard to its practicality and accuracy. Social simulation's simplification of the complex to form models from which we can better understand the latter is sometimes seen as a draw back, as using fairly simple models to simulate real life with computers is not always the best way to predict behavior. Most of the criticism seems to be aimed at agent-based models and simulation and how they work: Simulations, being man-made from mathematical interfaces, predict human behavior in a far too simple manner in regard to the complexities of humanity and our actions. Simulations cannot enlighten researchers as to how people interact or behave in ways not programmed into their models.
Membrane lipids Summary Membrane_lipid Membrane lipids are a group of compounds (structurally similar to fats and oils) which form the lipid bilayer of the cell membrane. The three major classes of membrane lipids are phospholipids, glycolipids, and cholesterol. Lipids are amphiphilic: they have one end that is soluble in water ('polar') and an ending that is soluble in fat ('nonpolar').
Classical theory Comparison with modern physics Classical_theory > Comparison with modern physics From the point of view of classical physics as being non-relativistic physics, the predictions of general and special relativity are significantly different from those of classical theories, particularly concerning the passage of time, the geometry of space, the motion of bodies in free fall, and the propagation of light. Traditionally, light was reconciled with classical mechanics by assuming the existence of a stationary medium through which light propagated, the luminiferous aether, which was later shown not to exist. Mathematically, classical physics equations are those in which Planck's constant does not appear.
Axiom of constructibility Implications Axiom_of_constructibility > Implications The axiom of constructibility implies the axiom of choice (AC), given Zermelo–Fraenkel set theory without the axiom of choice (ZF). It also settles many natural mathematical questions that are independent of Zermelo–Fraenkel set theory with the axiom of choice (ZFC); for example, the axiom of constructibility implies the generalized continuum hypothesis, the negation of Suslin's hypothesis, and the existence of an analytical (in fact, Δ 2 1 {\displaystyle \Delta _{2}^{1}} ) non-measurable set of real numbers, all of which are independent of ZFC. The axiom of constructibility implies the non-existence of those large cardinals with consistency strength greater or equal to 0#, which includes some "relatively small" large cardinals. For example, no cardinal can be ω1-Erdős in L. While L does contain the initial ordinals of those large cardinals (when they exist in a supermodel of L), and they are still initial ordinals in L, it excludes the auxiliary structures (e.g. measures) which endow those cardinals with their large cardinal properties.
Anonymous P2P Summary Anonymous_P2P An anonymous P2P communication system is a peer-to-peer distributed application in which the nodes, which are used to share resources, or participants are anonymous or pseudonymous. Anonymity of participants is usually achieved by special routing overlay networks that hide the physical location of each node from other participants.Interest in anonymous P2P systems has increased in recent years for many reasons, ranging from the desire to share files without revealing one's network identity and risking litigation to distrust in governments, concerns over mass surveillance and data retention, and lawsuits against bloggers.
Scientific management Taylorism and unions Taylor_system > Taylorism and unions Once the time-and-motion men had completed their studies of a particular task, the workers had very little opportunity for further thinking, experimenting, or suggestion-making. Taylorism was criticized for turning the worker into an "automaton" or "machine", making work monotonous and unfulfilling by doing one small and rigidly defined piece of work instead of using complex skills with the whole production process done by one person. "The further 'progress' of industrial development... increased the anomic or forced division of labor," the opposite of what Taylor thought would be the effect.

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