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Shear velocity Friction velocity in turbulence Shear_velocity > Friction velocity in turbulence The friction velocity is often used as a scaling parameter for the fluctuating component of velocity in turbulent flows. One method of obtaining the shear velocity is through non-dimensionalization of the turbulent equations of motion. For example, in a fully developed turbulent channel flow or turbulent boundary layer, the streamwise momentum equation in the very near wall region reduces to: 0 = ν ∂ 2 u ¯ ∂ y 2 − ∂ ∂ y ( u ′ v ′ ¯ ) {\displaystyle 0={\nu }{\partial ^{2}{\overline {u}} \over \partial y^{2}}-{\frac {\partial }{\partial y}}({\overline {u'v'}})} .By integrating in the y-direction once, then non-dimensionalizing with an unknown velocity scale u∗ and viscous length scale ν/u∗, the equation reduces down to: τ w ρ = ν ∂ u ∂ y − u ′ v ′ ¯ {\displaystyle {\frac {\tau _{w}}{\rho }}=\nu {\frac {\partial u}{\partial y}}-{\overline {u'v'}}} or τ w ρ u ⋆ 2 = ∂ u + ∂ y + + τ T + ¯ {\displaystyle {\frac {\tau _{w}}{\rho u_{\star }^{2}}}={\frac {\partial u^{+}}{\partial y^{+}}}+{\overline {\tau _{T}^{+}}}} .Since the right hand side is in non-dimensional variables, they must be of order 1. This results in the left hand side also being of order one, which in turn give us a velocity scale for the turbulent fluctuations (as seen above): u ⋆ = τ w ρ {\displaystyle u_{\star }={\sqrt {\frac {\tau _{w}}{\rho }}}} .Here, τw refers to the local shear stress at the wall.
Active immunotherapy Vaccine Therapies Active_immunotherapy > Specific active immunotherapy > Vaccine Therapies Vaccine therapies are a type of specific active immunotherapy. Vaccine therapies deliver various agents that will lead to a specific immune response e.g. antibody development or CTL response. Tumor antigens have been a main target in specific active immunotherapy by way of vaccination. Tumor antigens are antigens produced by tumor cells and can be common among patients with the same cancer-type, or unique to a particular patient. Their specificity to malignant tumor cells makes tumor antigens ideal candidates for vaccination.
Consensus decision-making Groupthink Consensus_decision_making > Criticism > Groupthink Some consider all unanimity a form of groupthink, and some experts propose "coding systems ... for detecting the illusion of unanimity symptom". In Consensus is not Unanimity, long-time progressive change activist Randy Schutt writes: Many people think of consensus as simply an extended voting method in which everyone must cast their votes the same way. Since unanimity of this kind rarely occurs in groups with more than one member, groups that try to use this kind of process usually end up being either extremely frustrated or coercive.
Outline of solar energy Conversion of solar energy Outline_of_solar_energy > Conversion of solar energy Role of copper in generating and transmitting energy with maximum efficiency in solar photovoltaic power generation, concentrating solar thermal power, and solar water heaters. Solar cell efficiency – Solar cell – made from a monocrystalline silicon wafer Solar chemical – a number of possible processes that harness solar energy by absorbing sunlight in a chemical reaction in a way similar to photosynthesis in plants but without using living organisms. Solar constant – a measure of flux density, it is the amount of incoming solar electromagnetic radiation per unit area that would be incident on a plane perpendicular to the rays, at a distance of one astronomical unit (AU) (roughly the mean distance from the Sun to the Earth). Solar inverter – or PV inverter, converts the variable direct current output of a photovoltaic (PV) solar panel into a utility frequency alternating current that can be fed into a commercial electrical grid or used by a local, off-grid electrical network. Solar photovoltaics –
Lebesgue integral Non-negative functions Lebesgue_integrable > Definition > Via simple functions > Non-negative functions We have defined the integral of f for any non-negative extended real-valued measurable function on E. For some functions, this integral ∫ E f d μ {\textstyle \int _{E}f\,d\mu } is infinite. It is often useful to have a particular sequence of simple functions that approximates the Lebesgue integral well (analogously to a Riemann sum). For a non-negative measurable function f, let s n ( x ) {\textstyle s_{n}(x)} be the simple function whose value is k / 2 n {\textstyle k/2^{n}} whenever k / 2 n ≤ f ( x ) < ( k + 1 ) / 2 n {\textstyle k/2^{n}\leq f(x)<(k+1)/2^{n}} , for k a non-negative integer less than, say, 4 n {\textstyle 4^{n}} . Then it can be proven directly that and that the limit on the right hand side exists as an extended real number. This bridges the connection between the approach to the Lebesgue integral using simple functions, and the motivation for the Lebesgue integral using a partition of the range.
Draculin Structure Draculin > Structure Draculin is a single-chain protein composed of 708 amino acids, weighing about 83 kDa with a pI of 4.1-4.2. When reduced, the gel electrophoresis data indicates a slightly higher molecular mass suggesting intra-chain disulphide bonds.There are two different structural forms of draculin. However, the two forms do not significantly differ from the other. Both structures are able to and do bind to coagulation factors IXa and Xa.
Decidability (logic) Relationship to computability Decidability_(computer_science) > Relationship to computability As with the concept of a decidable set, the definition of a decidable theory or logical system can be given either in terms of effective methods or in terms of computable functions. These are generally considered equivalent per Church's thesis. Indeed, the proof that a logical system or theory is undecidable will use the formal definition of computability to show that an appropriate set is not a decidable set, and then invoke Church's thesis to show that the theory or logical system is not decidable by any effective method (Enderton 2001, pp. 206ff. ).
BeH2 Reaction with water and acids Beryllium_hydride > Chemical properties > Reaction with water and acids Beryllium hydride reacts slowly with water but is rapidly hydrolysed by acid such as hydrogen chloride to form beryllium chloride. BeH2 + 2 H2O → Be(OH)2 + 2 H2BeH2 + 2 HCl → BeCl2 + 2 H2
Taylor's Theorem Summary Quadratic_approximation Taylor's theorem is named after the mathematician Brook Taylor, who stated a version of it in 1715, although an earlier version of the result was already mentioned in 1671 by James Gregory.Taylor's theorem is taught in introductory-level calculus courses and is one of the central elementary tools in mathematical analysis. It gives simple arithmetic formulas to accurately compute values of many transcendental functions such as the exponential function and trigonometric functions. It is the starting point of the study of analytic functions, and is fundamental in various areas of mathematics, as well as in numerical analysis and mathematical physics. Taylor's theorem also generalizes to multivariate and vector valued functions.
Surge impedance Lossless line Surge_impedance_loading > Lossless line The above expression is wholly real, since the imaginary term j has canceled out, implying that Z o {\displaystyle Z_{\text{o}}} is purely resistive. For a lossless line terminated in Z o {\displaystyle Z_{\text{o}}} , there is no loss of current across the line, and so the voltage remains the same along the line. The lossless line model is a useful approximation for many practical cases, such as low-loss transmission lines and transmission lines with high frequency.
Probabilistic Roadmap Method Summary Probabilistic_roadmap The rate of convergence depends on certain visibility properties of the free space, where visibility is determined by the local planner. Roughly, if each point can "see" a large fraction of the space, and also if a large fraction of each subset of the space can "see" a large fraction of its complement, then the planner will find a path quickly. The invention of the PRM method is credited to Lydia E. Kavraki.
Conjugated double bond Summary Conjugation_(organic_chemistry) Molecules containing conjugated systems of orbitals and electrons are called conjugated molecules, which have overlapping p orbitals on three or more atoms. Some simple organic conjugated molecules are 1,3-butadiene, benzene, and allylic carbocations. The largest conjugated systems are found in graphene, graphite, conductive polymers and carbon nanotubes.
Glass-working lathe Components Reducing_lathe > Design > Components Some motors have electronic rheostat-type speed controls, which obviates cone pulleys or gears. The counterpoint to the headstock is the tailstock, sometimes referred to as the loose head, as it can be positioned at any convenient point on the bed by sliding it to the required area.
Complexification Formal definition Complexification > Formal definition {\displaystyle \alpha (v\otimes \beta )=v\otimes (\alpha \beta )\qquad {\mbox{ for all }}v\in V{\mbox{ and }}\alpha ,\beta \in \mathbb {C} .} More generally, complexification is an example of extension of scalars – here extending scalars from the real numbers to the complex numbers – which can be done for any field extension, or indeed for any morphism of rings. Formally, complexification is a functor VectR → VectC, from the category of real vector spaces to the category of complex vector spaces.
Left-right model Example: u and d quarks in QCD Left-right_symmetry > Chiral symmetry > Example: u and d quarks in QCD The singlet vector symmetry, U(1)V, acts as q L → e i θ ( x ) q L q R → e i θ ( x ) q R , {\displaystyle q_{\rm {L}}\rightarrow e^{i\theta (x)}q_{\rm {L}}\qquad q_{\rm {R}}\rightarrow e^{i\theta (x)}q_{\rm {R}}~,} and thus invariant under U(1) gauge symmetry. This corresponds to baryon number conservation. The singlet axial group U(1)A transforms as the following global transformation q L → e i θ q L q R → e − i θ q R .
Genetic purging The mechanism Genetic_purging > The mechanism This causes some increase in the selective pressure against (partially) recessive deleterious alleles, which is known as purging. Of course, it also causes some reduction in fitness, which is known as inbreeding depression. Purging can reduce the average frequency of deleterious alleles across the genome below the value expected in a non-inbred population.
Antineoplastic resistance Genome alterations Antineoplastic_resistance > Acquired resistance > Genetic causes > Genome alterations Chromosomal rearrangement due to genome instability can cause gene amplification and deletion. Gene amplification is the increase in copy number of a region of a chromosome. which occur frequently in solid tumors, and can contribute to tumor evolution through altered gene expression.Hamster cell research in 1993 showed that amplifications in the DHFR gene involved in DNA synthesis began with chromosome break in below the gene, and subsequent cycles of bridge-breakage-fusion formations result in large intrachromosomal repeats. The over amplification of oncogenes can occur in response to chemotherapy, thought to be the underlying mechanism in several classes of resistance.
History of the Church–Turing thesis Church definition of "effectively calculable" History_of_the_Church–Turing_thesis > Church definition of "effectively calculable" "Footnote 9 is in section §4 Recursive functions: " 9This definition is closely related to, and was suggested by, a definition of recursive functions which was proposed by Kurt Gödel, in lectures at Princeton, N. J., 1934, and credited by him in part to an unpublished suggestion of Jacques Herbrand. The principal features in which present definition of recursiveness differs from Gödel's are due to S. C. Kleene. " In a forthcoming paper by Kleene to be entitled "General recursive functions of natural numbers," ... it follows ... that every function recursive in the present sense is also recursive in the sense of Gödel (1934) and conversely.
Domain Model Summary Domain_Model In software engineering, a domain model is a conceptual model of the domain that incorporates both behavior and data. In ontology engineering, a domain model is a formal representation of a knowledge domain with concepts, roles, datatypes, individuals, and rules, typically grounded in a description logic.
Ayttm Aycryption Ayttm > Features > Aycryption Aycryption is a filter that facilitates encrypted chat using GPG keys. All outgoing text is encrypted using the remote contact's public key, and incoming encrypted text is decrypted using the local private key.
Pareto chart Summary Pareto_chart A Pareto chart is a type of chart that contains both bars and a line graph, where individual values are represented in descending order by bars, and the cumulative total is represented by the line. The chart is named for the Pareto principle, which, in turn, derives its name from Vilfredo Pareto, a noted Italian economist.
Gauge field theories Quantization of gauge theories Gauge_Theory > Quantization of gauge theories Gauge theories may be quantized by specialization of methods which are applicable to any quantum field theory. However, because of the subtleties imposed by the gauge constraints (see section on Mathematical formalism, above) there are many technical problems to be solved which do not arise in other field theories. At the same time, the richer structure of gauge theories allows simplification of some computations: for example Ward identities connect different renormalization constants.
Speed Networking For participants Speed_Networking > Advantages and disadvantages > For participants However, there are also risks for attendees, and these relate to an unfortunate perception that a business relationship can also be speed-tracked, as well as a misconception that quantity is of prime importance. Members still need to take time to develop relationships with individual fellow members outside the networking event and the importance of this cannot be overestimated. Other principles of good networking, such as an attitude of giving, not pushing, business cards or marketing material at people, for example, still stand. People can not just drop in during a round robin event as it disrupts the flow and matching.
Database modelling Relational model Database_modelling > Relational model First, the ordering of columns is immaterial in a table. Second, there can not be identical tuples or rows in a table. And third, each tuple will contain a single value for each of its attributes.
LH (complexity) Summary LH_(complexity) In computational complexity, the logarithmic time hierarchy (LH) is the complexity class of all computational problems solvable in a logarithmic amount of computation time on an alternating Turing machine with a bounded number of alternations. It is a particular case of a bounded alternating Turing machine hierarchy. It is equal to FO and to FO-uniform AC0.The i {\displaystyle i} th level of the logarithmic time hierarchy is the set of languages recognised by alternating Turing machines in logarithmic time with random access and i − 1 {\displaystyle i-1} alternations, beginning with an existential state. LH is the union of all levels. == References ==
Polynomial algebra Factorization Multivariate_polynomial_ring > Univariate polynomials over a field > Factorization The existence of a factorization algorithm depends also on the ground field. In the case of the real or complex numbers, Abel–Ruffini theorem shows that the roots of some polynomials, and thus the irreducible factors, cannot be computed exactly. Therefore, a factorization algorithm can compute only approximations of the factors.
Integrate-and-fire model Relation between artificial and biological neuron models Integrate-and-fire_model > Relation between artificial and biological neuron models The most basic model of a neuron consists of an input with some synaptic weight vector and an activation function or transfer function inside the neuron determining output. This is the basic structure used for artificial neurons, which in a neural network often looks like y i = φ ( ∑ j w i j x j ) {\displaystyle y_{i}=\varphi \left(\sum _{j}w_{ij}x_{j}\right)} where yi is the output of the i th neuron, xj is the jth input neuron signal, wij is the synaptic weight (or strength of connection) between the neurons i and j, and φ is the activation function. While this model has seen success in machine-learning applications, it is a poor model for real (biological) neurons, because it lacks time-dependence in input and output.
Family roller coaster Mechanics Family_roller_coaster > Mechanics Roller coaster trains are not typically powered. Most are pulled up a lift hill by a chain or cable and released downhill. The potential energy accumulated by the rise in height is transferred to kinetic energy, which is then converted back into potential energy as the train rises up the next hill. Changes in elevation become smaller throughout the track's course, as some mechanical energy is lost to friction and air drag.
Format-preserving encryption Other FPE constructions Format-preserving_encryption > Algorithms > Other FPE constructions The paper "Format-Preserving Encryption" by Mihir Bellare and Thomas Ristenpart describes using "nearly balanced" Feistel networks to create secure FPE algorithms. The paper "Format Controlling Encryption Using Datatype Preserving Encryption" by Ulf Mattsson describes other ways to create FPE algorithms. An example of FPE algorithm is FNR (Flexible Naor and Reingold).
Elliptic Curve DSA Signature generation algorithm Elliptic_Curve_DSA > Signature generation algorithm (Here HASH is a cryptographic hash function, such as SHA-2, with the output converted to an integer.) Let z {\displaystyle z} be the L n {\displaystyle L_{n}} leftmost bits of e {\displaystyle e} , where L n {\displaystyle L_{n}} is the bit length of the group order n {\displaystyle n} .
Hubble radius Summary Hubble_radius In cosmology, a Hubble volume (named for the astronomer Edwin Hubble) or Hubble sphere, Hubble bubble, subluminal sphere, causal sphere and sphere of causality is a spherical region of the observable universe surrounding an observer beyond which objects recede from that observer at a rate greater than the speed of light due to the expansion of the universe. The Hubble volume is approximately equal to 1031 cubic light years (or about 1079 cubic meters). The proper radius of a Hubble sphere (known as the Hubble radius or the Hubble length) is c / H 0 {\displaystyle c/H_{0}} , where c {\displaystyle c} is the speed of light and H 0 {\displaystyle H_{0}} is the Hubble constant.
G actin Equivalents in prokaryotes F_actin > Evolution > Equivalents in prokaryotes The bacterial cytoskeleton contains proteins that are highly similar to actin monomers and polymers. The bacterial protein MreB polymerizes into thin non-helical filaments and occasionally into helical structures similar to F-actin. Furthermore, its crystalline structure is very similar to that of G-actin (in terms of its three-dimensional conformation), there are even similarities between the MreB protofilaments and F-actin. The bacterial cytoskeleton also contains the FtsZ proteins, which are similar to tubulin.Bacteria therefore possess a cytoskeleton with homologous elements to actin (for example, MreB, AlfA, ParM, FtsA, and MamK), even though the amino acid sequence of these proteins diverges from that present in animal cells.
Organic photorefractive materials Theory Organic_photorefractive_materials > Theory Then, the density of free carriers in the conduction and/or the valence band will increase. To account for these changes, steady-state Fermi levels are defined for electrons to be EFn and, for holes – EFp. The densities n and h are, then equal to n = N c e − ( E c − E F n ) k B T {\displaystyle n=N_{c}e^{\frac {-(E_{c}-E_{Fn})}{k_{B}T}}} h = N v e − ( E F p − E v ) k B T {\displaystyle h=N_{v}e^{\frac {-(E_{Fp}-E_{v})}{k_{B}T}}} The localized states between EFn and EFp are known as 'photoactive centers'.
Interlingual machine translation Translation process Interlingual_machine_translation > Translation process A conceptual lexicon (specific to the domain), which is the knowledge base about events and entities known in the domain. A set of projection rules (specific to the domain and the languages). Grammars for the analysis and generation of the languages involved.One of the problems of knowledge-based machine translation systems is that it becomes impossible to create databases for domains larger than very specific areas. Another is that processing these databases is very computationally expensive.
Bipolar junction transistors Active-mode transistors in circuits Junction_transistor > Regions of operation > Active-mode transistors in circuits That is, when a small change in the currents occurs, and sufficient time has passed for the new condition to reach a steady state h fe {\displaystyle h_{\text{fe}}} is the ratio of the change in collector current to the change in base current. The symbol β {\displaystyle \beta } is used for both h FE {\displaystyle h_{\text{FE}}} and h fe {\displaystyle h_{\text{fe}}} . : 62–66 The emitter current is related to V BE {\displaystyle V_{\text{BE}}} exponentially. At room temperature, an increase in V BE {\displaystyle V_{\text{BE}}} by approximately 60 mV increases the emitter current by a factor of 10. Because the base current is approximately proportional to the collector and emitter currents, they vary in the same way.
Human memory Long-term memory Human_memory > Long-term memory More recent examination of his brain, post-mortem, shows that the hippocampus was more intact than first thought, throwing theories drawn from the initial data into question. The hippocampus may be involved in changing neural connections for a period of three months or more after the initial learning. Research has suggested that long-term memory storage in humans may be maintained by DNA methylation, and the 'prion' gene.Further research investigated the molecular basis for long-term memory.
M/G/k queue Model definition M/G/k_queue > Model definition A queue represented by a M/G/k queue is a stochastic process whose state space is the set {0,1,2,3...}, where the value corresponds to the number of customers in the queue, including any being served. Transitions from state i to i + 1 represent the arrival of a new customer: the times between such arrivals have an exponential distribution with parameter λ. Transitions from state i to i − 1 represent the departure of a customer who has just finished being served: the length of time required for serving an individual customer has a general distribution function. The lengths of times between arrivals and of service periods are random variables which are assumed to be statistically independent.
Carbon monoxide toxicity Central nervous system effects Carbon_monoxide_toxicity > Pathophysiology > Central nervous system effects The result of these effects is lipid peroxidation, which causes delayed reversible demyelination of white matter in the central nervous system known as Grinker myelinopathy, which can lead to edema and necrosis within the brain. This brain damage occurs mainly during the recovery period. This may result in cognitive defects, especially affecting memory and learning, and movement disorders. These disorders are typically related to damage to the cerebral white matter and basal ganglia. Hallmark pathological changes following poisoning are bilateral necrosis of the white matter, globus pallidus, cerebellum, hippocampus and the cerebral cortex.
Electron tunneling Cold emission Quantum_tunnelling > Applications > Solid-state physics > Cold emission Cold emission of electrons is relevant to semiconductors and superconductor physics. It is similar to thermionic emission, where electrons randomly jump from the surface of a metal to follow a voltage bias because they statistically end up with more energy than the barrier, through random collisions with other particles. When the electric field is very large, the barrier becomes thin enough for electrons to tunnel out of the atomic state, leading to a current that varies approximately exponentially with the electric field. These materials are important for flash memory, vacuum tubes, as well as some electron microscopes.
Split-brain Hemispheric specialization Split-brain > Hemispheric specialization The two hemispheres of the cerebral cortex are linked by the corpus callosum, through which they communicate and coordinate actions and decisions. Communication and coordination between the two hemispheres is essential because each hemisphere has some separate functions. The right hemisphere of the cortex excels at nonverbal and spatial tasks, whereas the left hemisphere is more dominant in verbal tasks, such as speaking and writing. The right hemisphere controls the primary sensory functions of the left side of the body.
Population standard deviation Interpretation and application Sample_standard_deviation > Interpretation and application When deciding whether measurements agree with a theoretical prediction, the standard deviation of those measurements is of crucial importance: if the mean of the measurements is too far away from the prediction (with the distance measured in standard deviations), then the theory being tested probably needs to be revised. This makes sense since they fall outside the range of values that could reasonably be expected to occur, if the prediction were correct and the standard deviation appropriately quantified. See prediction interval. While the standard deviation does measure how far typical values tend to be from the mean, other measures are available. An example is the mean absolute deviation, which might be considered a more direct measure of average distance, compared to the root mean square distance inherent in the standard deviation.
Primosome Summary Primosome They are involved in primosome function both at arrested replication forks and at the chromosomal origin. Our biochemical analysis of the DnaB and DnaD proteins unravels their role in primosome assembly. They are both multimeric and bind individually to DNA.
Strength of ships Loads on ship hulls Strength_of_ships > Loads on ship hulls The weight of the hull is similarly calculated for that length, and the weight of equipment and systems. Cargo weight is then added in to that section depending on the loading conditions being checked. The total still water bending moment is then calculated by integrating the difference between buoyancy and total weight along the length of the ship.
Second principle of thermodynamics Living organisms Second_law_of_thermodynamics > Living organisms There are two principal ways of formulating thermodynamics, (a) through passages from one state of thermodynamic equilibrium to another, and (b) through cyclic processes, by which the system is left unchanged, while the total entropy of the surroundings is increased. These two ways help to understand the processes of life. The thermodynamics of living organisms has been considered by many authors, including Erwin Schrödinger (in his book What is Life?)
Buformin Mechanism of action Buformin > Mechanism of action Buformin delays absorption of glucose from the gastrointestinal tract, increases insulin sensitivity and glucose uptake into cells, and inhibits synthesis of glucose by the liver. Buformin and the other biguanides are not hypoglycemic, but rather antihyperglycemic agents. They do not produce hypoglycemia; instead, they reduce basal and postprandial hyperglycemia in diabetics. Biguanides may antagonize the action of glucagon, thus reducing fasting glucose levels.
Prime harmonic series The harmonic series Prime_harmonic_series > The harmonic series First, we describe how Euler originally discovered the result. He was considering the harmonic series He had already used the following "product formula" to show the existence of infinitely many primes. Here the product is taken over the set of all primes. Such infinite products are today called Euler products. The product above is a reflection of the fundamental theorem of arithmetic. Euler noted that if there were only a finite number of primes, then the product on the right would clearly converge, contradicting the divergence of the harmonic series.
Mineral structures Unit cell Crystal_symmetry > Unit cell Crystal structure is described in terms of the geometry of arrangement of particles in the unit cells. The unit cell is defined as the smallest repeating unit having the full symmetry of the crystal structure. The geometry of the unit cell is defined as a parallelepiped, providing six lattice parameters taken as the lengths of the cell edges (a, b, c) and the angles between them (α, β, γ).
GNU Units Usage GNU_Units > Usage Units will output the result of the conversion in two lines. Usually, the first line (multiplication) is the desired result; the second line is the same conversion expressed as a division. Units can also function as a general-purpose scientific calculator; it includes several built-in mathematical functions such as sin, cos, atan, ln, exp, etc. Attempting to convert types of measurements that are incompatible will cause units to print a conformability error message and display a reduced form of each measurement.
Deep Learning Definition Deep_neural_network > Definition Deep learning is a class of machine learning algorithms that: 199–200 uses multiple layers to progressively extract higher-level features from the raw input. For example, in image processing, lower layers may identify edges, while higher layers may identify the concepts relevant to a human such as digits or letters or faces. From another angle to view deep learning, deep learning refers to "computer-simulate" or "automate" human learning processes from a source (e.g., an image of dogs) to a learned object (dogs). Therefore, a notion coined as "deeper" learning or "deepest" learning makes sense. The deepest learning refers to the fully automatic learning from a source to a final learned object. A deeper learning thus refers to a mixed learning process: a human learning process from a source to a learned semi-object, followed by a computer learning process from the human learned semi-object to a final learned object.
Intel Dynamic Acceleration Dual Dynamic Acceleration Intel_Dynamic_Acceleration > Dual Dynamic Acceleration With the introduction of quad core processors, Intel modified IDA and released Dual Dynamic Acceleration (DDA).
5-(carboxyamino)imidazole ribonucleotide mutase Summary 5-(carboxyamino)imidazole_ribonucleotide_mutase In enzymology, a 5-(carboxyamino)imidazole ribonucleotide mutase (EC 5.4.99.18) is an enzyme that catalyzes the chemical reaction 5-carboxyamino-1-(5-phospho-D-ribosyl)imidazole ⇌ {\displaystyle \rightleftharpoons } 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylateHence, this enzyme has one substrate, 5-carboxyamino-1-(5-phospho-D-ribosyl)imidazole, and one product, 5-amino-1-(5-phospho-D-ribosyl)imidazole-4-carboxylate. This enzyme belongs to the family of isomerases, specifically those intramolecular transferases transferring other groups. The systematic name of this enzyme class is 5-carboxyamino-1-(5-phospho-D-ribosyl)imidazole carboxymutase. Other names in common use include N5-CAIR mutase, PurE, N5-carboxyaminoimidazole ribonucleotide mutase, and class I PurE.
Dirac particle Identification of observables Dirac_equation > Physical interpretation > Identification of observables The critical physical question in a quantum theory is this: what are the physically observable quantities defined by the theory? According to the postulates of quantum mechanics, such quantities are defined by Hermitian operators that act on the Hilbert space of possible states of a system. The eigenvalues of these operators are then the possible results of measuring the corresponding physical quantity. In the Schrödinger theory, the simplest such object is the overall Hamiltonian, which represents the total energy of the system.
DNA damage checkpoint Mutation Double_strand_break > DNA damage > Mutation Thus, in a population of cells composing a tissue with replicating cells, mutant cells will tend to be lost. However, infrequent mutations that provide a survival advantage will tend to clonally expand at the expense of neighboring cells in the tissue. This advantage to the cell is disadvantageous to the whole organism because such mutant cells can give rise to cancer. Thus, DNA damage in frequently dividing cells, because it gives rise to mutations, is a prominent cause of cancer. In contrast, DNA damage in infrequently-dividing cells is likely a prominent cause of aging.
Glossary of biology C Glossary_of_biology > C colony comparative biology The use of comparative methods to study the similarities and differences between two or more biological organisms (e.g. two organisms from the same time period but different taxa, or two organisms from the same taxon but different times in evolutionary history). The side-by-side comparison of morphological or molecular characteristics of different organisms is the basis from which biologists infer the organisms' genetic relatedness and their natural histories. It is a fundamental tool in many biological disciplines, including anatomy, physiology, paleontology, and phylogenetics.
Friction drum Construction Friction_drum > Construction The membrane may be depressed with the thumb while playing to vary the pitch. When a cord is used the instrument may be referred to as a "string drum" or "lion's roar." In some friction drums, the friction is obtained by spinning the drum around a pivot.
Thermometric titration Apparatus and setup for automated thermometric titrimetry Thermometric_titration > Apparatus and setup for automated thermometric titrimetry A suitable setup for automated thermometric titrimetry comprises the following: Precision fluid dispensing devices – "burettes" – for adding titrants and dosing of other reagents Thermistor-based thermometric sensor Titration vessel Stirring device, capable of highly efficient stirring of vessel contents without splashing Computer with thermometric titration operating system Thermometric titration interface module – this regulates the data flow between the burettes, sensors and the computerFigure 6 illustrates a modern automated thermometric titration system based on the Metrohm 859 Titrotherm interface module with Thermoprobe sensor, Metrohm 800 Dosino dispensing devices and a computer running the operational software. Figure 7 is a schematic of the relationship between components in automated thermometric titration system. A = dosing device B = thermometric sensor C = stirring device D = thermometric titration interface module E = computer
Waste management Recycling Waste_disposal > Recycling Recycling is a resource recovery practice that refers to the collection and reuse of waste materials such as empty beverage containers. This process involves breaking down and reusing materials that would otherwise be gotten rid of as trash. There are numerous benefits of recycling, and with so many new technologies making even more materials recyclable, it is possible to clean up the Earth. Recycling not only benefits the environment but also positively affects the economy.
Abdominal obesity Diet Central_obesity > Causes > Diet Quality protein uptake is defined as the ratio of essential amino acids to daily dietary protein.Visceral fat cells will release their metabolic by-products in the portal circulation, where the blood leads straight to the liver. Thus, the excess of triglycerides and fatty acids created by the visceral fat cells will go into the liver and accumulate there. In the liver, most of it will be stored as fat. This concept is known as 'lipotoxicity'.
Quantum Well Infrared Photodetector History Quantum_Well_Infrared_Photodetector > History In 1985, Stephen Eglash and Lawrence West observed strong intersubband transition in multiple quantum wells (MQW) that prompted more serious consideration into using quantum wells for infrared detectors. Previously, attempts to use quantum wells for infrared detection were based on free absorption in quantum wells that bring the electrons over the top of the barriers. However, resulting detectors displayed low sensitivity.By 1987, the basic operating principles for a quantum well infrared photodetector that demonstrated sensitive infrared detection were formulated. In 1990, the low-temperature sensitivity of the technology was further improved by increasing the barrier thickness, which suppressed the tunneling current.
Slow strain rate testing The evaluation of the results Slow_strain_rate_testing > The evaluation of the results The evaluated parameters are: time to specimen failure (e.g., breakage, or from other "failure" criteria) ductility (by elongation to fracture or the reduction of the area) ultimate tensile strength (from the maximum load) area under the elongation - load curve (which represents the fracture energy) percent of ductile/brittle fracture on the fracture surface threshold stress for crackingThe results of the SSRT tests are evaluated using the ratio: {\displaystyle \left} The departure of the ratio below unity quantifies the increased susceptibility to cracking. The test is best used in combination with electrochemical measurements and other stress corrosion cracking tests. == References ==
Tegmental pontine reticular nucleus Summary Tegmental_pontine_reticular_nucleus The reticulotegmental nucleus has been known to mediate eye movements, otherwise known as saccadic movement. This makes sense concerning their connections, as it would require a nucleus that receives and projects to the cerebellum to mediate that kind of complex circuitry. Furthermore, in terms of behavior, one does not think about saccadic movements when scanning a room, as the saccadic movements are not directly controlled by the cortex.
Nucleophilic catalysis Proton donors or acceptors Enzyme_catalysis > Mechanisms of an alternative reaction route > Proton donors or acceptors Many reaction mechanisms involving acid/base catalysis assume a substantially altered pKa. This alteration of pKa is possible through the local environment of the residue. pKa can also be influenced significantly by the surrounding environment, to the extent that residues which are basic in solution may act as proton donors, and vice versa.
Model of computation Sequential models Models_of_computation > Models > Sequential models Sequential models include: Finite state machines Post machines (Post–Turing machines and tag machines). Pushdown automata Register machines Random-access machines Turing machines Decision tree model
Intramembrane protease Distribution Intramembrane_protease > Distribution Intramembrane proteases are found in all domains of life, and all four groups are widely distributed. In eukaryotes, all membrane-bound organelles except peroxisomes have at least one intramembrane protease.
Gastroesophageal reflux disease Research Gastric_reflux > Research A number of endoscopic devices have been tested to treat chronic heartburn. Endocinch puts stitches in the lower esophogeal sphincter (LES) to create small pleats to help strengthen the muscle. However, long-term results were disappointing, and the device is no longer sold by Bard. The Stretta procedure uses electrodes to apply radio-frequency energy to the LES.
Masculine ordinal indicator Similar conventions Ordinal_dot > Similar conventions For example: Ex.mo for Excelentíssimo (an honorific), L.da for Limitada (Ltd. ), and Sr.ª for Senhora (Ms.). English has borrowed the No. abbreviation from the Romance-language word numero, which itself derives from the Latin word numero, the ablative case of the word numerus ('number'). This is sometimes written as No, with the superscript o optionally underlined, or sometimes with the ordinal indicator. In this case the ordinal indicator would simply represent the letter o in numero; see numero sign.
Mathematical biologist Evolutionary biology Theoretical_Biology > Areas of research > Evolutionary biology When infinitesimal effects at a large number of gene loci are considered, together with the assumption of linkage equilibrium or quasi-linkage equilibrium, one derives quantitative genetics. Ronald Fisher made fundamental advances in statistics, such as analysis of variance, via his work on quantitative genetics. Another important branch of population genetics that led to the extensive development of coalescent theory is phylogenetics.
Ischemic cell death Comparison to Apoptosis Ischemic_cell_death > Comparison to Apoptosis Oligonuclosomal DNA fragmentation is initiated by caspase-activated deoxyribonuclease following caspase-3 mediated cleavage of the enzyme’s inhibitor, ICAD. In contrast, the oncotic pathway has been shown to be caspase-3 independent.The primary determinant of cell death occurring via the oncotic or apoptotic pathway is cellular ATP levels. Apoptosis is contingent upon ATP levels to form the energy dependent apoptosome.
Lift (soaring) Dynamic soaring Lift_(soaring) > Dynamic soaring In dynamic soaring energy is gained by repeatedly crossing the boundary between air masses of different horizontal velocity rather than by rising air. Such zones of high "wind gradient" are usually too close to the ground to be used safely by gliders, but Albatrosses and model gliders use this phenomenon.
Discrete fixed-point theorem Summary Discrete_fixed-point_theorem In discrete mathematics, a discrete fixed-point is a fixed-point for functions defined on finite sets, typically subsets of the integer grid Z n {\displaystyle \mathbb {Z} ^{n}} . Discrete fixed-point theorems were developed by Iimura, Murota and Tamura, Chen and Deng and others. Yang provides a survey.
Geometric integrator Pendulum example Geometric_integrator > Pendulum example Define z ( t ) = ( q ( t ) , p ( t ) ) T {\displaystyle z(t)=(q(t),p(t))^{\mathrm {T} }} and f ( z ) = ( p , − sin ⁡ q ) T {\displaystyle f(z)=(p,-\sin q)^{\mathrm {T} }} . Let us experiment by using some simple numerical methods to integrate this system.
Bremsstrahlung Simplified quantum-mechanical description Bremsstrahlung_radiation > Simplified quantum-mechanical description We present some approximate results with the following additional assumptions: Vacuum interaction: we neglect any effects of the background medium, such as plasma screening effects. This is reasonable for photon frequency much greater than the plasma frequency ν p e ∝ n e 1 / 2 {\displaystyle \nu _{\rm {pe}}\propto n_{\rm {e}}^{1/2}} with n e {\displaystyle n_{e}} the plasma electron density. Note that light waves are evanescent for ν < ν p e {\displaystyle \nu <\nu _{\rm {pe}}} and a significantly different approach would be needed.
Concentration cell Active-passive cells Concentration_cell > Active-passive cells If a metal is protected against corrosion by a tightly adhering passive film (usually an oxide) and salt deposits on the surface in the presence of water, the active metal beneath the film will be exposed to corrosive attack in areas where the passive film is broken. An electrical potential will develop between the large area of the passive film (cathode) and the small area of the exposed active metal (anode). Rapid pitting of the active metal will result.
Passive sign convention Sign conventions Passive_sign_convention > Explanation > Sign conventions So power flowing into the component from the line is defined as positive; the power variable represents power dissipation in the component. Therefore Active components (power sources) will have negative resistance and negative power flow Passive components (loads) will have positive resistance and positive power flowThis is the convention normally used.Active sign convention: the reference direction of the current variable (the arrow representing the direction of positive current) points into the negative reference terminal of the voltage variable. This means that if the voltage and current variables have positive values, current flows through the device from the negative to the positive terminal, so work is being done on the current, and power flows out of the component.
Minor spliceosome Early evidence Minor_spliceosome > Early evidence Hall and R.A. Padgett compared the primary sequence of all reports on the four genes mentioned above. The results suggested a new type of introns with ATATCCTT 5' splice sites and YCCAC 3' splice sites and an almost invariant TCCTTAAC sequence near the 3' end of the introns (so called 3' upstream element).
Scheffé's lemma Summary Scheffé's_lemma In mathematics, Scheffé's lemma is a proposition in measure theory concerning the convergence of sequences of integrable functions. It states that, if f n {\displaystyle f_{n}} is a sequence of integrable functions on a measure space ( X , Σ , μ ) {\displaystyle (X,\Sigma ,\mu )} that converges almost everywhere to another integrable function f {\displaystyle f} , then ∫ \| f n − f \| d μ → 0 {\displaystyle \int \|f_{n}-f\|\,d\mu \to 0} if and only if ∫ \| f n \| d μ → ∫ \| f \| d μ {\displaystyle \int \|f_{n}\|\,d\mu \to \int \|f\|\,d\mu } .In probability theory, almost sure convergence can be weakened to requiring only convergence in probability.
Response priming Rapid-chase theory Response_priming > Theories > Rapid-chase theory The rapid-chase theory of response priming was proposed in 2006 by Thomas Schmidt, Silja Niehaus, and Annabel Nagel. It ties the direct parameter specification model to findings that newly occurring visual stimuli elicit a wave of neuronal activation in the visuomotor system, which spreads rapidly from visual to motor areas of the cortex. Because the wavefront of activity spreads very fast, Victor Lamme and Pieter Roelfsema from the University of Amsterdam have proposed that this wave starts as a pure feedforward process (feedforward sweep): A cell first reached by the wavefront has to pass on its activity before being able to integrate feedback from other cells. Lamme and Roelfsema assume that this kind of feedforward processing is not sufficient to generate visual awareness of the stimulus: For this, neuronal feedback and recurrent processing loops are required that link widespread neuronal networks.According to rapid-chase theory, both primes and targets elicit feedforward sweeps that traverse the visuomotor system in rapid succession until they reach motor areas of the brain.
Lamb wave Lamb's characteristic equations Lamb_wave > Lamb's characteristic equations In general, elastic waves in solid materials are guided by the boundaries of the media in which they propagate. An approach to guided wave propagation, widely used in physical acoustics, is to seek sinusoidal solutions to the wave equation for linear elastic waves subject to boundary conditions representing the structural geometry. This is a classic eigenvalue problem. Waves in plates were among the first guided waves to be analyzed in this way.
Laplacian of the indicator Fluid dynamics Laplacian_of_the_indicator > Applications > Fluid dynamics The Laplacian of the indicator has been used in fluid dynamics, e.g. to model the interfaces between different media.
Unmanned Ground Vehicle Guidance interface Unmanned_tank > Design > Guidance interface Depending on the type of control system, the interface between machine and human operator can include joystick, computer programs, or voice command.
State machine replication Ordering Inputs State_machine_replication > The State Machine Approach > Ordering Inputs Consensus Order may be derived independently by each server. Inputs to the State Machine may be executed in Consensus Order, guaranteeing consistent State and Output for all non-faulty replicas. Optimizing Causal & Consensus Ordering In some cases additional information is available (such as real-time clocks).
Contextual image classification Markov meshes Contextual_image_classification > Algorithms > Markov meshes The lower-order Markov chain and Hilbert space-filling curves mentioned above are treating the image as a line structure. The Markov meshes however will take the two dimensional information into account.
Salting in Anionic interactions Salting_in > Anionic interactions The abundance of the salt ions decreases the solvating power of salt ions, resulting in the decrease in the solubility of the proteins and precipitation results.At high salt concentrations, the solubility is given by the following empirical expression. log S = B − KIwhere S is the solubility of the protein, B is a constant (function of protein, pH and temperature), K is the salting out constant (function of pH, mixing and salt), and I is the ionic strength of the salt. This expression is an approximation to that proposed by Long and McDevit.
Enneagram of Personality Figure Enneagram_of_Personality > Figure The enneagram figure is composed of three parts; a circle, an inner triangle (connecting 3-6-9), and an irregular hexagonal "periodic figure" (connecting 1-4-2-8-5-7). According to esoteric spiritual traditions, the circle symbolizes unity, the inner triangle symbolizes the "law of three" and the hexagram represents the "law of seven" (because 1-4-2-8-5-7-1 is the repeating decimal created by dividing one by seven in base 10 arithmetic). These three elements constitute the usual enneagram figure.
Mode of failure Failure by corrosion Failure_mechanism > Types of failure causes > Failure by corrosion Materials can be degraded by their environment by corrosion processes, such as rusting in the case of iron and steel. Such processes can also be affected by load in the mechanisms of stress corrosion cracking and environmental stress cracking.
Para-allopatric speciation Environmental gradients Para-allopatric_speciation > Models > Environmental gradients : 113 With this interpretation, his verbal, theoretical model can effectively produce a new species; of which was subsequently confirmed mathematically. : 113 Further mathematical models have been developed to demonstrate the possibility of clinal speciation with most relying on, what Coyne and Orr assert are, "assumptions that are either restrictive or biologically unrealistic". : 113 A mathematical model for clinal speciation was developed by Caisse and Antonovics that found evidence that, "both genetic divergence and reproductive isolation may therefore occur between populations connected by gene flow".
Hyperplane Applications Hyperplane > Applications In convex geometry, two disjoint convex sets in n-dimensional Euclidean space are separated by a hyperplane, a result called the hyperplane separation theorem. In machine learning, hyperplanes are a key tool to create support vector machines for such tasks as computer vision and natural language processing. The datapoint and its predicted value via a linear model is a hyperplane.
Asymptotic series Summary Asymptotic_expansions Repeated integration by parts will often lead to an asymptotic expansion. Since a convergent Taylor series fits the definition of asymptotic expansion as well, the phrase "asymptotic series" usually implies a non-convergent series. Despite non-convergence, the asymptotic expansion is useful when truncated to a finite number of terms.
Procedural knowledge Development Procedural_knowledge > Development The development of procedural knowledge is always entangled with the development of declarative knowledge. Researchers suggested that initial problem solving involves explicitly referring to examples, participants start with pure example-based processing. The examples illustrate the solution of a similar problem and the problem solver analogically maps the solution of the example onto a solution for the current problem. People make extensive reference to examples even when they are initially taught the rules and principles.
Antiarin Physiological systems affected/medical properties Antiarin > Physiological systems affected/medical properties However, the very effect that allows β-antiarin to be a poison also gives it medicinal properties. It limits the sodium ion (Na+) concentration by blocking the Na+ pump, which then promotes calcium ions (Ca2+) to increase in concentration in the extracellular cardiac muscle domain, therein permitting the heart to contract. The mechanism through which sodium and calcium ions are exchanged, known as the sodium-calcium exchanger, allows for the exchange of ions to occur at a rate of 3:1 respectively.
Two-vector Summary Two-vector Notice that both indices of the components are contravariant. This is always the case for two-vectors, by definition.
Reaction vessel Overview Chemical_reactors > Overview The reactants, in liquid or gas phase, are pumped through the catalyst bed. A chemical reactor may also be a fluidized bed; see Fluidized bed reactor. Chemical reactions occurring in a reactor may be exothermic, meaning giving off heat, or endothermic, meaning absorbing heat. A tank reactor may have a cooling or heating jacket or cooling or heating coils (tubes) wrapped around the outside of its vessel wall to cool down or heat up the contents, while tubular reactors can be designed like heat exchangers if the reaction is strongly exothermic, or like furnaces if the reaction is strongly endothermic.
Meta-learning (computer science) Summary Meta-learning_(computer_science) Meta learning is a subfield of machine learning where automatic learning algorithms are applied to metadata about machine learning experiments. As of 2017, the term had not found a standard interpretation, however the main goal is to use such metadata to understand how automatic learning can become flexible in solving learning problems, hence to improve the performance of existing learning algorithms or to learn (induce) the learning algorithm itself, hence the alternative term learning to learn.Flexibility is important because each learning algorithm is based on a set of assumptions about the data, its inductive bias. This means that it will only learn well if the bias matches the learning problem. A learning algorithm may perform very well in one domain, but not on the next.
List of uncertainty propagation software Software List_of_uncertainty_propagation_software > Software NIST Uncertainty Machine is an uncertainty calculator that uses Gauss' formula and Monte Carlo methods. Users access it through a web browser, but it runs in the R programming language on the server. Complete documentation.
Intelligence quotient Reliability Intelligence_quotient > Reliability and validity > Reliability On aggregate, IQ tests exhibit high reliability, although test-takers may have varying scores when taking the same test on differing occasions, and may have varying scores when taking different IQ tests at the same age. Like all statistical quantities, any particular estimate of IQ has an associated standard error that measures uncertainty about the estimate. For modern tests, the confidence interval can be approximately 10 points and reported standard error of measurement can be as low as about three points.
PCI bus PCI command codes PCI_Local_Bus > PCI bus transactions > PCI command codes All 32 bits of the read address are provided, so that a device may (for compatibility reasons) implement less than 4 bytes worth of I/O registers. If the byte enables request data not within the address range supported by the PCI device (e.g. a 4-byte read from a device which only supports 2 bytes of I/O address space), it must be terminated with a target abort. Multiple data cycles are permitted, using linear (simple incrementing) burst ordering.
Computer assisted proof Methods Computer-aided_proof > Methods More precisely, one reduces the computation to a sequence of elementary operations, say ( + , − , × , / ) {\displaystyle (+,-,\times ,/)} . In a computer, the result of each elementary operation is rounded off by the computer precision. However, one can construct an interval provided by upper and lower bounds on the result of an elementary operation. Then one proceeds by replacing numbers with intervals and performing elementary operations between such intervals of representable numbers.
Spontaneous emission Rate of spontaneous emission Spontaneous_emission > Rate of spontaneous emission The above equation clearly shows that the rate of spontaneous emission in free space increases proportionally to ω 3 {\displaystyle \omega ^{3}} . In contrast with atoms, which have a discrete emission spectrum, quantum dots can be tuned continuously by changing their size. This property has been used to check the ω 3 {\displaystyle \omega ^{3}} -frequency dependence of the spontaneous emission rate as described by Fermi's golden rule.
Geophysical MASINT Sea bottom measurement Geophysical_MASINT > Weather and sea intelligence MASINT > Hydrographic sensors > Sea bottom measurement A variety of sensors can be used to characterise the sea bottom into, for example, mud, sand, and gravel. Active acoustic sensors are the most obvious, but there is potential information from gravimetric sensors, electro-optical and radar sensors for making inferences from the water surface, etc. Relatively simple sonars such as echo sounders can be promoted to seafloor classification systems via add-on modules, converting echo parameters into sediment type. Different algorithms exist, but they are all based on changes in the energy or shape of the reflected sounder pings. Side-scan sonars can be used to derive maps of the topography of an area by moving the sonar across it just above the bottom.
Collision attack Classical collision attack Chosen-prefix_attack > Classical collision attack However, workarounds are possible by abusing dynamic constructs present in many formats. In this way, two documents would be created which are as similar as possible in order to have the same hash value. One document would be shown to an authority to be signed, and then the signature could be copied to the other file.

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