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End user license agreement Enforceability of EULAs in the United States End_user_license_agreement > Enforceability of EULAs in the United States In Anti-UCITA states, the Uniform Commercial Code (UCC) has been amended to either specifically define software as a good (thus making it fall under the UCC), or to disallow contracts which specify that the terms of contract are subject to the laws of a state that has passed UCITA. Recently, publishers have begun to encrypt their software packages to make it impossible for a user to install the software without either agreeing to the license agreement or violating the Digital Millennium Copyright Act (DMCA) and foreign counterparts.The DMCA specifically provides for reverse engineering of software for interoperability purposes, so there was some controversy as to whether software license agreement clauses which restrict this are enforceable. The 8th Circuit case of Davidson & Associates v. Jung determined that such clauses are enforceable, following the Federal Circuit decision of Baystate v. Bowers.
Graph homology General case Graph_homology > The 0-th homology group > General case The above example can be generalized to any connected graph. Starting from any vertex, it is possible to get to any other vertex by adding to it one or more expressions corresponding to edges (e.g. starting from x, one can get to z by adding y-x and z-y). Since the elements of im ⁡ ∂ 1 {\displaystyle \operatorname {im} \partial _{1}} are all equivalent to zero, it means that all vertices of the graph are in a single equivalence class, and therefore H 0 ( X ) {\displaystyle H_{0}(X)} is isomorphic to Z. In general, the graph can have several connected components.
Vladimir Krivchenkov Interpretation of Quantum mechanics Vladimir_Krivchenkov > Interpretation of Quantum mechanics Then, immediately, probability appears, because classical mechanics cannot interpret events in a deterministic way. An intermediate step is provided by the formalism of the density matrix, that allows us to keep some quantum mechanical properties in the classical description; however, such a description is not complete and it is just a compromise between the deterministic description of too complicated a system and wishes to make any (at least probabilistic) predictions. As an example of the superiority of quantum mechanics, Krivchenkov usually cited the 3-body problem.
Inductive impedance Deriving the device-specific impedances Complex_Impedance > Device examples > Deriving the device-specific impedances What follows below is a derivation of impedance for each of the three basic circuit elements: the resistor, the capacitor, and the inductor. Although the idea can be extended to define the relationship between the voltage and current of any arbitrary signal, these derivations assume sinusoidal signals. In fact, this applies to any arbitrary periodic signals, because these can be approximated as a sum of sinusoids through Fourier analysis.
Prognostics Summary Prognostics The science of prognostics is based on the analysis of failure modes, detection of early signs of wear and aging, and fault conditions. An effective prognostics solution is implemented when there is sound knowledge of the failure mechanisms that are likely to cause the degradations leading to eventual failures in the system. It is therefore necessary to have initial information on the possible failures (including the site, mode, cause and mechanism) in a product.
Equivariant morphism Summary Intertwining_operator In mathematics, equivariance is a form of symmetry for functions from one space with symmetry to another (such as symmetric spaces). A function is said to be an equivariant map when its domain and codomain are acted on by the same symmetry group, and when the function commutes with the action of the group. That is, applying a symmetry transformation and then computing the function produces the same result as computing the function and then applying the transformation. Equivariant maps generalize the concept of invariants, functions whose value is unchanged by a symmetry transformation of their argument.
Luteinizing hormone-releasing hormone Function Gonadotropin_releasing_hormone > Function GnRH is secreted in the hypophysial portal bloodstream at the median eminence. The portal blood carries the GnRH to the pituitary gland, which contains the gonadotrope cells, where GnRH activates its own receptor, gonadotropin-releasing hormone receptor (GnRHR), a seven-transmembrane G-protein-coupled receptor that stimulates the beta isoform of Phosphoinositide phospholipase C, which goes on to mobilize calcium and protein kinase C. This results in the activation of proteins involved in the synthesis and secretion of the gonadotropins LH and FSH. GnRH is degraded by proteolysis within a few minutes. GnRH activity is very low during childhood, and is activated at puberty or adolescence.
Generalized Bernoulli numbers A binary tree representation Generalized_Bernoulli_numbers > A binary tree representation {\displaystyle N!=a_{1}\prod _{k=2}^{\operatorname {length} (N)}a_{k}!.} Restricted to the nodes N of a fixed tree-level n the sum of 1/N! is σn(1), thus B n = ∑ tree-level n N node of n !
Reservoir computing Reservoir computing on gate-based near-term superconducting quantum computers Reservoir_computing > Quantum reservoir computing > Types > Reservoir computing on gate-based near-term superconducting quantum computers The most prevalent model of quantum computing is the gate-based model where quantum computation is performed by sequential applications of unitary quantum gates on qubits of a quantum computer. A theory for the implementation of reservoir computing on a gate-based quantum computer with proof-of-principle demonstrations on a number of IBM superconducting noisy intermediate-scale quantum (NISQ) computers has been reported in.
Industrial processes Summary Industrial_processes Industrial processes are procedures involving chemical, physical, electrical, or mechanical steps to aid in the manufacturing of an item or items, usually carried out on a very large scale. Industrial processes are the key components of heavy industry.
SequenceL Design SequenceL > Design From this formal definition, SequenceL infers the dimensions of the defined product from the formula for its (i, j)'th entry (as the set of pairs (i, j) for which the right hand side is defined) and computes each entry by the same formula as in the informal definition above. Notice there are no explicit instructions for iteration in this definition, or for the order in which operations are to be carried out. Because of this, the SequenceL compiler can perform operations in any order (including parallel order) which satisfies the defining equation.
Endogenous regeneration Neural stem cells in the adult brain Endogenous_regeneration > Neural stem cells in the adult brain During the early development of a human, neural stem cells lie in the germinal layer of the developing brain, ventricular and subventricular zones. In brain development, multipotent stem cells (those that can generate different types of cells) are present in these regions, and all of these cells differentiate into neural cell forms, such as neurons, oligodendrocytes and astrocytes. A long-held belief states that the multipotency of neural stem cells would be lost in the adult human brain. However, it is only in vitro, using neurosphere and adherent monolayer cultures, that stem cells from the adult mammalian brain have shown multipotent capacity, while the in vivo study is not convincing.
Wheel speed sensor Bearingless wheelset speed sensors Wheel_speed_sensor > Special purpose speed sensors > Speed sensors on the wheelset > Bearingless wheelset speed sensors Bearingless speed sensors may be found in almost every wheelset of a rail vehicle. They are principally used for wheel slide protection and usually supplied by the manufacturer of the wheel slide protection system. These sensors require a sufficiently small air gap and need to be particularly reliable. One special feature of rotary speed sensors that are used for wheel slide protection is their integrated monitoring functions.
Cardiorespiratory fitness Summary Cardiorespiratory_fitness Cardiorespiratory fitness (CRF) refers to the ability of the circulatory and respiratory systems to supply oxygen to skeletal muscles during sustained physical activity. Scientists and researchers use CRF to assess the functional capacity of the respiratory and cardiovascular systems. These functions include ventilation, perfusion, gas exchange, vasodilation, and delivery of oxygen to the body's tissues. As these body's functions are vital to an individual's health, CRF allows observers to quantify an individual's morbidity and mortality risk as a function of cardiorespiratory health.
Philosophy of biology Biological laws and autonomy of biology Philosophy_of_biology > Biological laws and autonomy of biology As individual organisms must be understood in the context of their ecosystems, holists argue, so must lower-level biological processes be understood in the broader context of the living organism in which they take part. Proponents of this view cite our growing understanding of the multidirectional and multilayered nature of gene modulation (including epigenetic changes) as an area where a reductionist view is inadequate for full explanatory power.All processes in organisms obey physical laws, but some argue that the difference between inanimate and biological processes is that the organisation of biological properties is subject to control by coded information. This has led biologists and philosophers such as Ernst Mayr and David Hull to return to the strictly philosophical reflections of Charles Darwin to resolve some of the problems which confronted them when they tried to employ a philosophy of science derived from classical physics.
Thomas Bayes Summary Thomas_Bayes Thomas Bayes ( BAYZ ; c. 1701 – 7 April 1761) was an English statistician, philosopher and Presbyterian minister who is known for formulating a specific case of the theorem that bears his name: Bayes' theorem. Bayes never published what would become his most famous accomplishment; his notes were edited and published posthumously by Richard Price.
Open ocean convection Summary Open_ocean_convection Open ocean convection is a process in which the mesoscale ocean circulation and large, strong winds mix layers of water at different depths. Fresher water lying over the saltier or warmer over the colder leads to the stratification of water, or its separation into layers. Strong winds cause evaporation, so the ocean surface cools, weakening the stratification. As a result, the surface waters are overturned and sink while the "warmer" waters rise to the surface, starting the process of convection.
Class stratification Class schema Class_stratification > Class schema Social class is usually regarded as being conceived of as sets of positions rather than as individuals who happen to fill them at any particular time. Class structure is the “empty spaces” that persons occupy without altering the shape of the class structure. Erik Olin Wright produced class schemata, in attempts to retain a Marxist approach to class analysis. In Wright’s first schema he states that in capitalism simple production exists alongside the capitalist mode of production.
Platelet count Immune function Blood_platelet > Immune function Platelets have a central role in innate immunity, initiating and participating in multiple inflammatory processes, directly binding pathogens and even destroying them. This supports clinical data which show that many with serious bacterial or viral infections have thrombocytopenia, thus reducing their contribution to inflammation. Platelet-leukocyte aggregates (PLAs) found in circulation are typical in sepsis or inflammatory bowel disease, showing the connection between thrombocytes and immune cells.The platelet cell membrane has receptors for collagen. Following the rupture of the blood vessel wall, the platelets are exposed and they adhere to the collagen in the surrounding connective tissue.
Digital read out Magnetic scales Digital_read_out > Linear encoders > Magnetic scales Magnetic scales use an embedded magnetic strip to track position. Benefits include being coolant and dust proof. Unique to magnetic scales is the ability for the user to cut or shorten them to a desired length.
Algorithm aversion Perceptions about algorithm capabilities and performance Algorithm_aversion > Factors affecting algorithm aversion > Perceptions about algorithm capabilities and performance Overall, people tend to judge machines more critically than they do humans. Several system characteristics or factors have been shown to influence how people evaluate algorithms.
Optical Fourier transform Derivation of the convolution equation Fourier_optics > Optical systems: general overview and analogy with electrical signal processing systems > Derivation of the convolution equation This is where the convolution equation above comes from. The convolution equation is useful because it is often much easier to find the response of a system to a delta function input - and then perform the convolution above to find the response to an arbitrary input - than it is to try to find the response to the arbitrary input directly. Also, the impulse response (in either time or frequency domains) usually yields insight to relevant figures of merit of the system.
Molybdenum ditelluride Crystal form Molybdenum(IV)_telluride > Physical properties > Crystal form The layers are thus in two different positions. The crystal is very easily cleaved on the plane between the three layer sheets. The sizes change with temperature, at 100 K a=3.492 Å and at 400 K is 3.53 Å. In the same range c changes from 13.67 Å to 14.32 Å due to thermal expansion.
Beta Chi Theta Beating Heart Disease Beta_Chi_Theta > Philanthropy > Beating Heart Disease In 2009, the fraternity selected cardiac health awareness as its national philanthropy because this is the number one cause of death in the world and it is especially rampant amongst the South Asian population. Since then, it has partnered with the American Heart Association to teach communities how to live a heart-healthy lifestyle and to raise money for cardiac research and education. The Beating Heart Disease program is a series of week-long events held by chapters in the spring of each year to educate students on cardiac health and to raise money for the American Heart Association. An additional aspect of this partnership involves the participation in Heart Walks, which are hosted annually across the nation by the American Heart Association.
Heat sink Methods to determine performance Heat_sink > Methods to determine performance In general, a heat sink performance is a function of material thermal conductivity, dimensions, fin type, heat transfer coefficient, air flow rate, and duct size. To determine the thermal performance of a heat sink, a theoretical model can be made. Alternatively, the thermal performance can be measured experimentally. Due to the complex nature of the highly 3D flow in present applications, numerical methods or computational fluid dynamics (CFD) can also be used. This section will discuss the aforementioned methods for the determination of the heat sink thermal performance.
History of systems of units of measurement Metric system History_of_systems_of_units_of_measurement > Metric system In some engineering fields, like computer-aided design, millimetre–gram–second (mmgs) is also used.The current international standard for the metric system is the International System of Units (Système international d'unités or SI). It is a system in which all units can be expressed in terms of seven units. The units that serves as the SI base units are the metre, kilogram, second, ampere, kelvin, mole, and candela.
Conceptual framework Overview Conceptual_framework > Overview Formal hypotheses posit possible explanations (answers to the why question) that are tested by collecting data and assessing the evidence (usually quantitative using statistical tests). For example, Kai Huang wanted to determine what factors contributed to residential fires in U.S. cities.
Nandrolone decanoate Pharmacokinetics Nandrolone_decanoate > Pharmacology > Pharmacokinetics The pharmacokinetics of nandrolone decanoate via subcutaneous injection closely resemble those of intramuscular injection. However, subcutaneous injection is considered to be easier, more convenient, and less painful compared to intramuscular injection. In addition, research suggests that most intramuscular injections in practice are in fact subcutaneous injections.
Loop Current Effect on tropical cyclones Loop_Current > Effect on tropical cyclones In the Gulf of Mexico, the deepest areas of warm water are associated with the Loop Current. The rings of current that have separated from the Loop Current are commonly called Loop Current eddies. The warm waters of the Loop Current and its associated eddies provide more energy to hurricanes and allow them to intensify.
Design rule Free software Design_rule > Software > Free software Electric VLSI Design System KLayout Magic Alliance -- A Free VLSI/CAD System Opencircuitdesign software: Microwind -- An educational layout CAD system Opensource 130nm CMOS PDK by Google and SkyWater tech. Foundry
Process Automation System Process automation and energy efficiency Process_Automation_System > Process automation and energy efficiency Operator interfaces: Operator interfaces are used by human operators to monitor the process and make manual adjustments if necessary. These interfaces may include computer screens, buttons, and other controls. Communication networks: Communication networks are used to interconnect the various components of the automation system.
Breathing tube (breathing apparatus) Mountaineering rebreathers Breathing_bag > Fields of application > Mountaineering rebreathers Everest has a greater oxygen partial pressure than breathing air at sea level. This results in being able to exert greater physical effort at altitude.
PCMCIA card Type II PCMCIA_card > Card types > Type II Type-II and above PC Card devices use two rows of 34 sockets, and have a 16- or 32-bit interface. They are 5.0 millimetres (0.20 in) thick. Type-II cards introduced I/O support, allowing devices to attach an array of peripherals or to provide connectors/slots to interfaces for which the host computer had no built-in support.
Schrödinger field Identical particles Schrödinger_field > Exposition > Identical particles . , x N ) = V 1 , 2 ( x 1 , x 2 ) + V 1 , 3 ( x 2 , x 3 ) + V 2 , 3 ( x 1 , x 2 ) {\displaystyle V(x_{1}...,x_{N})=V_{1,2}(x_{1},x_{2})+V_{1,3}(x_{2},x_{3})+V_{2,3}(x_{1},x_{2})\,} then V 1 , 2 = V 1 , 3 = V 2 , 3 {\displaystyle V_{1,2}=V_{1,3}=V_{2,3}} and so on. In the Schrödinger equation formalism, the restrictions on the potential are ad-hoc, and the classical wave limit is hard to reach. It also has limited usefulness if a system is open to the environment, because particles might coherently enter and leave.
Photosynthetic reaction center Mechanism Photosynthetic_reaction_center > In bacteria > Mechanism First, the transfer of an electron from BPh− to P960+ is relatively slow compared to two other redox reactions in the reaction center. The faster reactions involve the transfer of an electron from BPh− (BPh− is oxidized to BPh) to the electron acceptor quinone (QA), and the transfer of an electron to P960+ (P960+ is reduced to P960) from a heme in the cytochrome subunit above the reaction center. The high-energy electron that resides on the tightly bound quinone molecule QA is transferred to an exchangeable quinone molecule QB.
Dirac Delta function Motivation and overview Dirac_distribution > Motivation and overview The Dirac delta is not truly a function, at least not a usual one with domain and range in real numbers. For example, the objects f(x) = δ(x) and g(x) = 0 are equal everywhere except at x = 0 yet have integrals that are different. According to Lebesgue integration theory, if f and g are functions such that f = g almost everywhere, then f is integrable if and only if g is integrable and the integrals of f and g are identical. A rigorous approach to regarding the Dirac delta function as a mathematical object in its own right requires measure theory or the theory of distributions.
Airship Propulsion and control Airship_gondola > Construction > Propulsion and control Instructions were relayed to them from the pilot's station by a telegraph system, as on a ship.If fuel is burnt for propulsion, then progressive reduction in the airship's overall weight occurs. In hydrogen airships, this is usually dealt with by simply venting cheap hydrogen lifting gas. In helium airships water is often condensed from the exhaust and stored as ballast.
Register pressure Code density Arithmetic_and_logic_operation > Instructions > Code density These types of cores often take little silicon to implement, so they can be easily realized in an FPGA or in a multi-core form. The code density of MISC is similar to the code density of RISC; the increased instruction density is offset by requiring more of the primitive instructions to do a task.There has been research into executable compression as a mechanism for improving code density. The mathematics of Kolmogorov complexity describes the challenges and limits of this.
Hereditary mutation Treatment Single_gene_disorder > Treatment This should alleviate the defect caused by a faulty gene or slow the progression of the disease. A major obstacle has been the delivery of genes to the appropriate cell, tissue, and organ affected by the disorder. Researchers have investigated how they can introduce a gene into the potentially trillions of cells that carry the defective copy. Finding an answer to this has been a roadblock between understanding the genetic disorder and correcting the genetic disorder.
RL filter Transfer functions RL_circuit > Series circuit > Transfer functions The transfer function to the inductor voltage is H L ( s ) = V L ( s ) V i n ( s ) = L s R + L s = G L e j ϕ L . {\displaystyle H_{L}(s)={\frac {V_{L}(s)}{V_{\mathrm {in} }(s)}}={\frac {Ls}{R+Ls}}=G_{L}e^{j\phi _{L}}\,.} Similarly, the transfer function to the resistor voltage is H R ( s ) = V R ( s ) V i n ( s ) = R R + L s = G R e j ϕ R . {\displaystyle H_{R}(s)={\frac {V_{R}(s)}{V_{\mathrm {in} }(s)}}={\frac {R}{R+Ls}}=G_{R}e^{j\phi _{R}}\,.} The transfer function, to the current, is H I ( s ) = I ( s ) V i n ( s ) = 1 R + L s . {\displaystyle H_{I}(s)={\frac {I(s)}{V_{\mathrm {in} }(s)}}={\frac {1}{R+Ls}}\,.}
System equivalence Discussion System_equivalence > Discussion Other laws include Fick's laws of diffusion and generalized transport problems. The most important idea is the flux, or rate of transfer of some important physical quantity considered (like electric or magnetic fluxes). In these sorts of systems, the energy is dominated by the derivative of the generalized position (generalized velocity). In physics parlance, these systems tend to be kinetic energy-dominated. Field theories, in particular electromagnetism, draw heavily from the hydraulic analogy.
Exoplanetary science Nodal precession Exoplanetary_science > Orbital parameters > Nodal precession Nodal precession is rotation of a planet's orbital plane. Nodal precession is more easily seen as distinct from periastron precession when the orbital plane is inclined to the star's rotation, the extreme case being a polar orbit. WASP-33 is a fast-rotating star that hosts a hot Jupiter in an almost polar orbit. The quadrupole mass moment and the proper angular momentum of the star are 1900 and 400 times, respectively, larger than those of the Sun. This causes significant classical and relativistic deviations from Kepler's laws. In particular, the fast rotation causes large nodal precession because of the star's oblateness and the Lense–Thirring effect.
Sarcolemma Summary Sarcolemma The sarcolemma (sarco (from sarx) from Greek; flesh, and lemma from Greek; sheath) also called the myolemma, is the cell membrane surrounding a skeletal muscle fiber or a cardiomyocyte. It consists of a lipid bilayer and a thin outer coat of polysaccharide material (glycocalyx) that contacts the basement membrane. The basement membrane contains numerous thin collagen fibrils and specialized proteins such as laminin that provide a scaffold to which the muscle fiber can adhere. Through transmembrane proteins in the plasma membrane, the actin skeleton inside the cell is connected to the basement membrane and the cell's exterior.
Egyptian algebra Aha problems, linear equations and false position Egyptian_algebra > Aha problems, linear equations and false position In modern mathematical notation, this linear equation is represented: 3 2 x + 4 = 10. {\displaystyle {\frac {3}{2}}x+4=10.} Solving these Aha problems involves a technique called method of false position.
Comparison of C Sharp and Java Object-oriented programming Comparison_of_C_Sharp_and_Java > Object-oriented programming Both C# and Java are designed from the ground up as object-oriented languages using dynamic dispatch, with syntax similar to C++ (C++ in turn derives from C). Neither language is a superset of C or C++, however.
Group (mathematics) Symmetry groups Group_(mathematics) > Examples and applications > Symmetry groups These symmetries underlie the chemical and physical behavior of these systems, and group theory enables simplification of quantum mechanical analysis of these properties. For example, group theory is used to show that optical transitions between certain quantum levels cannot occur simply because of the symmetry of the states involved.Group theory helps predict the changes in physical properties that occur when a material undergoes a phase transition, for example, from a cubic to a tetrahedral crystalline form. An example is ferroelectric materials, where the change from a paraelectric to a ferroelectric state occurs at the Curie temperature and is related to a change from the high-symmetry paraelectric state to the lower symmetry ferroelectric state, accompanied by a so-called soft phonon mode, a vibrational lattice mode that goes to zero frequency at the transition.Such spontaneous symmetry breaking has found further application in elementary particle physics, where its occurrence is related to the appearance of Goldstone bosons.
Pulmonary hemorrhage Pathophysiology Pulmonary_hemorrhage > Pathophysiology Although the pathogenesis is uncertain, it is probable that the symptoms are a consequence of hemorrhagic pulmonary edema, as the hematocrit is lower than normal blood (usually 15-20% less) and the concentration of small proteins is higher than in plasma. It is postulated that the infant suffers from asphyxia with resultant heart attack; this increases pulmonary microvascular pressure, resulting in pulmonary edema. Contributing factors include factors that favor increased filtration of fluid from pulmonary capillaries (e.g., low concentration of plasma proteins, high alveolar surface tension, lung damage, hypervolemia).
Natural Computation Artificial immune systems Natural_Computation > Nature-inspired models of computation > Artificial immune systems These include distinguishing between self and nonself, neutralization of nonself pathogens (viruses, bacteria, fungi, and parasites), learning, memory, associative retrieval, self-regulation, and fault-tolerance. Artificial immune systems are abstractions of the natural immune system, emphasizing these computational aspects. Their applications include computer virus detection, anomaly detection in a time series of data, fault diagnosis, pattern recognition, machine learning, bioinformatics, optimization, robotics and control.
RNA-binding protein Diversity Protein-RNA_interaction > Diversity As nuclear RNA emerges from RNA polymerase, RNA transcripts are immediately covered with RNA-binding proteins that regulate every aspect of RNA metabolism and function including RNA biogenesis, maturation, transport, cellular localization and stability. All RBPs bind RNA, however they do so with different RNA-sequence specificities and affinities, which allows the RBPs to be as diverse as their targets and functions. These targets include mRNA, which codes for proteins, as well as a number of functional non-coding RNAs. NcRNAs almost always function as ribonucleoprotein complexes and not as naked RNAs. These non-coding RNAs include microRNAs, small interfering RNAs (siRNA), as well as spliceosomal small nuclear RNAs (snRNA).
Locked twins Summary Locked_twins Locked twins is a rare complication of multiple pregnancy where two fetuses become interlocked during presentation before birth. It occurs in roughly 1 in 1,000 twin deliveries and 1 in 90,000 deliveries overall. Most often, locked twins are delivered via Caesarean section, given that the condition has been diagnosed early enough. The fetal mortality rate is high for the twin that presents first, with over 50% being stillborn.
PID Controller Applicability PID_loop > Fundamental operation > Applicability The use of the PID algorithm does not guarantee optimal control of the system or its control stability (see § Limitations, below). Situations may occur where there are excessive delays: the measurement of the process value is delayed, or the control action does not apply quickly enough. In these cases lead–lag compensation is required to be effective. The response of the controller can be described in terms of its responsiveness to an error, the degree to which the system overshoots a setpoint, and the degree of any system oscillation. But the PID controller is broadly applicable since it relies only on the response of the measured process variable, not on knowledge or a model of the underlying process.
Failure of electronic components Packaging failures Failure_of_electronic_components > Packaging failures Dies can crack due to mechanical overstress or thermal shock; defects introduced during processing, like scribing, can develop into fractures. Lead frames may contain excessive material or burrs, causing shorts.
Direct policy search Value function Inverse_reinforcement_learning > Algorithms for control learning > Value function Assuming full knowledge of the MDP, the two basic approaches to compute the optimal action-value function are value iteration and policy iteration. Both algorithms compute a sequence of functions Q k {\displaystyle Q_{k}} ( k = 0 , 1 , 2 , … {\displaystyle k=0,1,2,\ldots } ) that converge to Q ∗ {\displaystyle Q^{*}} . Computing these functions involves computing expectations over the whole state-space, which is impractical for all but the smallest (finite) MDPs. In reinforcement learning methods, expectations are approximated by averaging over samples and using function approximation techniques to cope with the need to represent value functions over large state-action spaces.
Electric ship Charger Electric_boat > Components > Charger Some solar panels, or photovoltaic arrays, can be flexible enough to fit to slightly curved surfaces and can be ordered in unusual shapes and sizes. Nonetheless, the heavier, rigid mono-crystalline types are more efficient in terms of energy output per square meter. The efficiency of solar panels rapidly decreases when they are not pointed directly at the sun, so some way of tilting the arrays while under way is very advantageous.
Covalent bond classification method Summary Covalent_Bond_Classification The covalent bond classification (CBC) method is also referred to as the LXZ notation. It was published by M. L. H. Green in 1995 as a solution for the need to describe covalent compounds such as organometallic complexes in a way that is not prone to limitations resulting from the definition of oxidation state. Instead of simply assigning a charge to an atom in the molecule (i.e. the oxidation state), the covalent bond classification method analyzes the nature of the ligands surrounding the atom of interest, which is often a transition metal.
Physics engine Summary Physics_engines A physics engine is computer software that provides an approximate simulation of certain physical systems, such as rigid body dynamics (including collision detection), soft body dynamics, and fluid dynamics, of use in the domains of computer graphics, video games and film (CGI). Their main uses are in video games (typically as middleware), in which case the simulations are in real-time. The term is sometimes used more generally to describe any software system for simulating physical phenomena, such as high-performance scientific simulation.
Grammaticality Research methods of sentence processing Grammaticality > Use of grammaticality judgments > Research methods of sentence processing There are several methods that successfully investigate sentence processing, some of which include eye tracking, self-paced listening and reading, or cross-modal priming. The most productive method however, is real-time grammaticality judgements. A grammaticality judgement is a test which involves showing participants sentences that are either grammatical or ungrammatical. The participant must decide whether or not they find the sentences to be grammatical as quickly as possible. Grammaticality is cross-linguistic, so this method has therefore been used on a wide variety of languages.
Alexander–Spanier cohomology Alexander cohomology with compact supports Alexander-Spanier_cohomology > Alexander cohomology with compact supports The cohomology module induced from the cochain complex C ¯ c ∗ {\displaystyle {\bar {C}}_{c}^{}} is called the Alexander cohomology of ( X , A ) {\displaystyle (X,A)} with compact supports and denoted by H ¯ c ∗ ( X , A ; G ) {\displaystyle {\bar {H}}_{c}^{}(X,A;G)} . Induced homomorphism of this cohomology is defined as the Alexander cohomology theory. Under this definition, we can modify homotopy axiom for cohomology to a proper homotopy axiom if we define a coboundary homomorphism δ ∗: H ¯ c q ( A ; G ) → H ¯ c q + 1 ( X , A ; G ) {\displaystyle \delta ^{*}:{\bar {H}}_{c}^{q}(A;G)\to {\bar {H}}_{c}^{q+1}(X,A;G)} only when A ⊂ X {\displaystyle A\subset X} is a closed subset. Similarly, excision axiom can be modified to proper excision axiom i.e. the excision map is a proper map.
High-altitude cerebral edema Signs and symptoms High-altitude_cerebral_edema > Signs and symptoms Early symptoms of HACE generally correspond with those of moderate to severe acute mountain sickness (AMS). Initial symptoms of HACE commonly include confusion, loss of consciousness, fever, ataxia, photophobia, rapid heart beat, lassitude, and an altered mental state. Those affected generally attempt to cease physical activities, regardless of their necessity for survival.
Outline of solar energy Appliances Outline_of_solar_energy > Applications of solar energy > Appliances Solar-powered fan – a mechanical fan powered by solar panels. Solar street light – are raised light sources which are powered by photovoltaic panels generally mounted on the lighting structure. Solar traffic light – are signalling devices powered by solar panels positioned at road intersections, pedestrian crossings and other locations to control the flows of traffic.
American kestrel Environmental disturbance American_kestrel > Stress physiology > Environmental disturbance American kestrels' response to environmental stress is measured as blood concentration of corticosterone (CORT), a hormone produced by the hypothalamic-pituitary-adrenal (HPA) axis that releases stored energy for essential body functions. Extended periods of elevated blood CORT levels may direct metabolic energy away from growth and reproduction. Thus, high levels of traffic disturbance and human development surrounding American kestrel nests are found to increase stress hormones leading to reproductive failure. Among successful nests, however, nestlings do not typically experience a higher stress response to environmental human disturbance, suggesting that they can tolerate a considerable degree of human activity near the nest.
Iodous acid Other oxyanions Iodous_acid > Other oxyanions Iodine can assume oxidation states of −1, +1, +3, +5, or +7. A number of neutral iodine oxides are also known. == References ==
Gibbs entropy formula Gibbs entropy formula Gibbs_entropy_formula > Gibbs entropy formula The von Neumann entropy formula is an extension of the Gibbs entropy formula to the quantum mechanical case. It has been shown that the Gibbs Entropy is equal to the classical "heat engine" entropy characterized by d S = δ Q T {\displaystyle dS={\frac {\delta Q}{T}}\!} , and the generalized Boltzmann distribution is a sufficient and necessary condition for this equivalence. Furthermore, the Gibbs Entropy is the only entropy that is equivalent to the classical "heat engine" entropy under the following postulates:
Telephoto lens Construction Telephoto_lens > Construction E.g., a telephoto lens might have a focal length of 400 mm, while it is shorter than that. A telephoto lens works by having the outermost (i.e. light gathering) element of a much shorter focal length than the equivalent long-focus lens and then incorporating a second set of elements close to the film or sensor plane that extend the cone of light so that it appears to have come from a lens of much greater focal length. The basic construction of a telephoto lens consists of front lens elements that, as a group, have a positive focus.
Cell unroofing Summary Cell_unroofing Cell unroofing is any of various methods to isolate and expose the cell membrane of cells. Differently from the more common membrane extraction protocols performed with multiple steps of centrifugation (which goal is to separate the membrane fraction from a cell lysate), in cell unroofing the aim is to tear and preserve patches of the plasma membrane in order to perform in situ experiments using (microscopy and biomedical spectroscopy).
PAS capacitor Automotive Super_capacitor > Applications > Transport > Automotive Toyota's Yaris Hybrid-R concept car uses a supercapacitor to provide bursts of power. PSA Peugeot Citroën has started using supercapacitors as part of its stop-start fuel-saving system, which permits faster initial acceleration. Mazda's i-ELOOP system stores energy in a supercapacitor during deceleration and uses it to power on-board electrical systems while the engine is stopped by the stop-start system.
Neurodegenerative disorders Genetics Neurodegenerative_disorder > Mechanisms > Genetics Many neurodegenerative diseases are caused by genetic mutations, most of which are located in completely unrelated genes. In many of the different diseases, the mutated gene has a common feature: a repeat of the CAG nucleotide triplet. CAG codes for the amino acid glutamine. A repeat of CAG results in a polyglutamine (polyQ) tract.
Autoantibody Production Autoantibody > Production Normally, the immune system is able to recognize and ignore the body's own healthy proteins, cells, and tissues, and to not overreact to non-threatening substances in the environment, such as foods. Sometimes, the immune system ceases to recognize one or more of the body's normal constituents as "self", leading to production of pathological autoantibodies. Autoantibodies may also play a nonpathological role; for instance they may help the body to destroy cancers and to eliminate waste products. The role of autoantibodies in normal immune function is also a subject of scientific research.
Binary classifier Summary Binary_classification Binary classification is the task of classifying the elements of a set into two groups (each called class) on the basis of a classification rule. Typical binary classification problems include: Medical testing to determine if a patient has certain disease or not; Quality control in industry, deciding whether a specification has been met; In information retrieval, deciding whether a page should be in the result set of a search or not.Binary classification is dichotomization applied to a practical situation. In many practical binary classification problems, the two groups are not symmetric, and rather than overall accuracy, the relative proportion of different types of errors is of interest. For example, in medical testing, detecting a disease when it is not present (a false positive) is considered differently from not detecting a disease when it is present (a false negative).
Macromolecular system Thermodynamics Supermolecular_chemistry > Control > Thermodynamics Supramolecular complexes are formed by non-covalent interactions between two chemical moieties, which can be described as an host and a guest. Most commonly, the interacting species are held together by hydrogen bonds. The definition excludes compounds formed by electrostatic interactions, which are called ion pairs. In solution, the host H, guest G, and complexes HpGq, will be in equilibrium with each other.
Phosmet Side effects Phosmet > Side effects Clothing, particularly gloves, provided substantial protection from exposures.The accumulation of acetylcholine leads to symptoms that mimic the muscarinic, nicotinic, and central nervous system actions of acetylcholine. Muscarinic signs and symptoms are tightness of the chest, bronchoconstriction, bradycardia, and constriction of the pupils. Salivation, lacrimation, and sweating are all increased, and peristalsis is also increased, leading to nausea, vomiting, and diarrhea.
Loop (algebra) Loops Inverse_property_loop > Loops A loop is a quasigroup with an identity element; that is, an element, e, such that x ∗ e = x and e ∗ x = x for all x in Q.It follows that the identity element, e, is unique, and that every element of Q has unique left and right inverses (which need not be the same). A quasigroup with an idempotent element is called a pique ("pointed idempotent quasigroup"); this is a weaker notion than a loop but common nonetheless because, for example, given an abelian group, (A, +), taking its subtraction operation as quasigroup multiplication yields a pique (A, −) with the group identity (zero) turned into a "pointed idempotent". (That is, there is a principal isotopy (x, y, z) ↦ (x, −y, z).) A loop that is associative is a group.
Solar thermal collector Space heating and ventilating Evacuated_tube > Solar thermal collectors heating air > Space heating and ventilating By drawing air through a properly designed unglazed transpired air collector or an air heater, the solar heated fresh air can reduce the heating load during daytime operation. Many applications are now being installed where the transpired collector preheats the fresh air entering a heat recovery ventilator to reduce the defrost time of HRV's. The higher your ventilation and temperature the better your payback time will be.
Implicit memory Priming studies Implicit_memory > Evidence and current research > Priming studies In contrast, HD patients evidenced little learning on a pursuit-rotor task that was easily mastered by both amnesic and DAT patients (Eslinger and Damasio, 1986; Heindel et al., 1988). This possible double dissociation involving HD and DAT patients suggests that different implicit memory tasks are mediated by distinct neural systems and that these tasks can be used to differentiate some of the so-called "cortical" (e.g., DAT) from "subcortical" (e.g., HD) dementias (Cummings and Benson, 1984).A more recent contribution to the study of implicit memory comes from the experiments with a spatial organization computer game on amnesic patients (Stickgold et al., 2000). Damage to the bilateral temporal lobe and hippocampus had caused the loss of explicit memory.
End table Types End_table > Types Drafting tables usually have a top that can be tilted for making a large or technical drawing. They may also have a ruler or similar element integrated. Workbenches are sturdy tables, often elevated for use with a high stool or while standing, which are used for assembly, repairs, or other precision handwork. Nested tables are a set of small tables of graduated size that can be stacked together, each fitting within the one immediately larger. They are for occasional use (such as a tea party), hence the stackable design.
Electric double-layer capacitor Internal resistance Hybrid_capacitor > Electrical parameters > Internal resistance Ri determines several supercapacitor properties. It limits the charge and discharge peak currents as well as charge/discharge times. Ri and the capacitance C results in the time constant τ {\displaystyle \tau } τ = R i ⋅ C {\displaystyle \tau =R_{\text{i}}\cdot C} This time constant determines the charge/discharge time.
Replication origin regions Replication machinery Template_replication > Replication process > Replication machinery The helicases remain associated for the remainder of replication process. Peter Meister et al. observed directly replication sites in budding yeast by monitoring green fluorescent protein (GFP)-tagged DNA polymerases α. They detected DNA replication of pairs of the tagged loci spaced apart symmetrically from a replication origin and found that the distance between the pairs decreased markedly by time. This finding suggests that the mechanism of DNA replication goes with DNA factories.
Pauling's rules First rule: the radius ratio rule Pauling's_rules > First rule: the radius ratio rule The cation and any two anions form a right triangle, with 2 r − = 2 ( r − + r + ) {\displaystyle 2r_{-}={\sqrt {2}}(r_{-}+r_{+})} , or 2 r − = r − + r + {\displaystyle {\sqrt {2}}r_{-}=r_{-}+r_{+}} . Then r + = ( 2 − 1 ) r − = 0.414 r − {\displaystyle r_{+}=({\sqrt {2}}-1)r_{-}=0.414r_{-}} . Similar geometrical proofs yield the minimum radius ratios for the highly symmetrical cases C.N.
Dynamic systems theory Nonlinear system Dynamical_systems_theory > Concepts > Nonlinear system In mathematics, a nonlinear system is a system that is not linear—i.e., a system that does not satisfy the superposition principle. Less technically, a nonlinear system is any problem where the variable(s) to solve for cannot be written as a linear sum of independent components. A nonhomogeneous system, which is linear apart from the presence of a function of the independent variables, is nonlinear according to a strict definition, but such systems are usually studied alongside linear systems, because they can be transformed to a linear system as long as a particular solution is known.
Complexity Classification Problems Complexity > Topics > Classification Problems There has also been interest in measuring the complexity of classification problems in supervised machine learning. This can be useful in meta-learning to determine for which data sets filtering (or removing suspected noisy instances from the training set) is the most beneficial and could be expanded to other areas. For binary classification, such measures can consider the overlaps in feature values from differing classes, the separability of the classes, and measures of geometry, topology, and density of manifolds.For non-binary classification problems, instance hardness is a bottom-up approach that first seeks to identify instances that are likely to be misclassified (assumed to be the most complex). The characteristics of such instances are then measured using supervised measures such as the number of disagreeing neighbors or the likelihood of the assigned class label given the input features.
Lebesgue integrable Introduction Lebesgue_integration > Introduction For example, the Dirichlet function, which is 0 where its argument is irrational and 1 otherwise, has a Lebesgue integral, but does not have a Riemann integral. Furthermore, the Lebesgue integral of this function is zero, which agrees with the intuition that when picking a real number uniformly at random from the unit interval, the probability of picking a rational number should be zero. Lebesgue summarized his approach to integration in a letter to Paul Montel: I have to pay a certain sum, which I have collected in my pocket.
Multipath TCP Use cases Multipath_TCP > Use cases Siri sends voice samples over an HTTPS session to Apple servers. Those servers reply with the information requested by the users. According to Apple engineers, the main benefits of Multipath TCP with this application are: User-feedback (Time-to-First-Word) 20% faster in the 95th percentile 5x reduction of network failuresOther deployment use Multipath TCP to aggregate the bandwidth of different networks.
Epigenetic theories of homosexuality Epigenetic marks Epigenetic_theories_of_homosexuality > Epigenetic marks Epigenetic marks (epi-marks) are temporary "switches" that control how our genes are expressed during gestation and after birth. Moreover, epi-marks are modifications of histone proteins. Epigenetic marks are modifications of the methyl and acetyl groups that bind to DNA histones thereby changing how the proteins function and as a result, alter gene expression. Epi-marks change how the histones function and as a result, influence the way genes are expressed.
Geographic speciation Summary Vicariant_speciation From this arises a host of various issues in defining species, defining isolating barriers, measuring reproductive isolation, among others. Nevertheless, verbal and mathematical models, laboratory experiments, and empirical evidence overwhelmingly supports the occurrence of allopatric speciation in nature. : 87–105 Mathematical modeling of the genetic basis of reproductive isolation supports the plausibility of allopatric speciation; whereas laboratory experiments of Drosophila and other animal and plant species have confirmed that reproductive isolation evolves as a byproduct of natural selection. : 87
Variable data publishing Summary Variable_data_publishing This ensures that the published content is available to recipients via any form of access method they might require. When multi-channel output is utilized, integrity between those output channels often becomes important. Variable-data publishing may be performed on everything from a personal computer to a mainframe system. However, the speed and practical output volumes which can be achieved are directly affected by the computer power utilized.
Forced move T Forced_move > T time 1. The amount of time each player has to think and calculate as measured by a chess clock.
Partially observable Markov decision process Summary Partially_observable_Markov_decision_process A partially observable Markov decision process (POMDP) is a generalization of a Markov decision process (MDP). A POMDP models an agent decision process in which it is assumed that the system dynamics are determined by an MDP, but the agent cannot directly observe the underlying state. Instead, it must maintain a sensor model (the probability distribution of different observations given the underlying state) and the underlying MDP. Unlike the policy function in MDP which maps the underlying states to the actions, POMDP's policy is a mapping from the history of observations (or belief states) to the actions.
Class size Summary Class_size Class size refers to the number of students a teacher faces during a given period of instruction.
Lattice field theory Summary Lattice_field_theory In physics, lattice field theory is the study of lattice models of quantum field theory, that is, of field theory on a space or spacetime that has been discretised onto a lattice.
Internet relationship Effects on face-to-face interactions Internet_relationship > Effects on face-to-face interactions Since the creation of the Internet, communication has become one of its prime uses. It has become a ubiquitous force in people's everyday lives due to the increase in the regularity and quality of interaction. The internet has also created a new approach to human relationships, and it has changed the way people connect to one another in their social worlds. Online relationships have also changed which effective strategies we use to perform maintenance on our relationships, depending on the exclusivity of the internet the relationship.
Infrared Spectrometer for ExoMars Summary Infrared_Spectrometer_for_ExoMars Infrared Spectrometer for ExoMars (ISEM) is an infrared spectrometer for remote sensing that is part of the science payload on board the European Space Agency's Rosalind Franklin rover, tasked to search for biosignatures and biomarkers on Mars. The rover is planned to be launched in August–October 2022 and land on Mars in spring 2023.ISEM will provide context assessment of the surface mineralogy in the vicinity of the Rosalind Franklin rover for selection of potential astrobiological targets. The Principal Investigator is Oleg Korablev from the Russian Space Research Institute (IKI).
Dural arteriovenous fistula Embolization Dural_arteriovenous_fistula > Treatment > Interventions > Embolization One approach used for treatment is embolization. A six-vessel angiogram is employed to determine the vascular supply to the fistula. Detachable coils, liquid embolic agents like NBCA, and onyx, or combinations of both are injected into the blood vessel to occlude the DAVF. Preoperative embolization can also be used to supplement surgery.
One-class classification PU (Positive Unlabeled) learning One-class_classification > Introduction > PU (Positive Unlabeled) learning A similar problem is PU learning, in which a binary classifier is learned in a semi-supervised way from only positive and unlabeled sample points.In PU learning, two sets of examples are assumed to be available for training: the positive set P {\displaystyle P} and a mixed set U {\displaystyle U} , which is assumed to contain both positive and negative samples, but without these being labeled as such. This contrasts with other forms of semisupervised learning, where it is assumed that a labeled set containing examples of both classes is available in addition to unlabeled samples. A variety of techniques exist to adapt supervised classifiers to the PU learning setting, including variants of the EM algorithm. PU learning has been successfully applied to text, time series, bioinformatics tasks, and Remote-Sensing Data.
Robert Edmund Froude Summary Robert_Edmund_Froude Robert Edmund Froude CB FRS (/ˈfruːd/; 22 December 1846 – 19 March 1924) (frequently styled in publication as R.E. Froude) was an English engineer, hydrodynamicist and naval architect who described momentum theory, both used in the systematic evaluation of propeller design efficiency and as components of blade element momentum theory.
Object oriented programming language History Object-oriented_languages > History Examples include the Intel iAPX 432 and the Linn Smart Rekursiv. In 1981, Goldberg edited the August issue of Byte Magazine, introducing Smalltalk and object-oriented programming to a wider audience. In 1986, the Association for Computing Machinery organised the first Conference on Object-Oriented Programming, Systems, Languages, and Applications (OOPSLA), which was unexpectedly attended by 1,000 people.
Cache coherency protocols (examples) Firefly (DEC) protocol Cache_coherency_protocols_(examples) > Coherency protocols > Firefly (DEC) protocol - If the data comes from a cache (Shared Line "on") a "Write-broadcasting" is sent to the bus to update all the other caches and the MM (Write Through). All the caches are set S - else the cache is set DBus transactionsBus Read- If hit (D or VE or S) the data is sent to the bus (intervention) and in case of D the data is written also in MM. The cache is set SBus Read- If hit (D or VE or S) the data is sent to the bus (Intervention). - All the caches are set SWrite Broadcasting- The cache is updated with new data. The state remains SOperations Write Allocate Intervention: from D-VE-S (from all "valid" caches) Write-broadcasting – Write through Copy-Back: D replacement and on any transaction with a cache D————————————————————————————————————————
Augmented transition network Summary Augmented_transition_network An augmented transition network or ATN is a type of graph theoretic structure used in the operational definition of formal languages, used especially in parsing relatively complex natural languages, and having wide application in artificial intelligence. An ATN can, theoretically, analyze the structure of any sentence, however complicated. ATN are modified transition networks and an extension of RTNs. ATNs build on the idea of using finite state machines (Markov model) to parse sentences.
Vertically transmitted infection Transplacental Vertically_transmitted_infection > Causal routes > Transplacental Often, microorganisms that produce minor illness in the mother are very dangerous for the developing embryo or fetus. This can result in spontaneous abortion or major developmental disorders. For many infections, the baby is more at risk at particular stages of pregnancy. Problems related to perinatal infection are not always directly noticeable.Apart from infecting the fetus, transplacental pathogens may cause placentitis (inflammation of the placenta) and/or chorioamnionitis (inflammation of the fetal membranes).
Functional derivative Definition Functional_derivative > Definition In this section, the functional differential (or variation or first variation) is defined. Then the functional derivative is defined in terms of the functional differential.
Adrenergic blocking agent Summary Adrenergic_blocking_agent Adrenergic blocking agents are a class of drugs that exhibit its pharmacological action through inhibiting the action of the sympathetic nervous system in the body. The sympathetic nervous system(SNS) is an autonomic nervous system that we cannot control by will. It triggers a series of responses after the body releases chemicals named noradrenaline and epinephrine.

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