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Motion diagram Summary Motion_diagram These spots reveal whether or not the object has accelerated or decelerated.For simplicity, the object is represented by a simple shape, such as a filled circle. It contains information about object positions at particular time instances. Therefore, a motion diagram is more informative than a path.
Controlled aerodynamic instability phenomena Justification Controlled_aerodynamic_instability_phenomena > Justification Following the same trend, other studies have already been carried out, for example the flutter power generation system proposed by Isogai et al. in 2003, which uses the flutter instability caused by the wind on an aerofoil to extract energy from the flow. In this branch, Matsumoto et al. went further, proposing enhancements for that system and assessing the feasibility of its usage with bluff bodies. The "kite motors" of Dave Santos utilize aerofoil instabilities.
Management of multiple sclerosis Medical treatments for symptoms Management_of_multiple_sclerosis > Managing the effects of MS > Medical treatments for symptoms Some of these recommendations do not come from specific studies in MS but are general recommendations for those who have neurogenic bladder. Bowel: bowel problems affect around 70% of the patients. Around 50% of patients have constipation and up to 30% have fecal incontinence.
Genetic susceptibility Healthcare and genomics Genetic_susceptibility > Genomics and health > Healthcare and genomics Members of the public are continually asking how obtaining their genetic blueprint will benefit them, and why they find that they are more susceptible to diseases that have no cures. Researchers have found that almost all disorders and diseases that affect humans reflect the interplay between the environment and their genes; however we are still in the initial stages of understanding the specific role genes play on common disorders and diseases. For example, while news reports may give a different impression, most cancer is not inherited. It is therefore likely that the recent rise in the rates of cancer worldwide can be at least partially attributed to the rise in the number of synthetic and otherwise toxic compounds found in our society today.
External ballistics Gyroscopic drift (Spin drift) Bullet_drop > Long range factors > Gyroscopic drift (Spin drift) Gyroscopic drift is an interaction of the bullet's mass and aerodynamics with the atmosphere that it is flying in. Even in completely calm air, with no sideways air movement at all, a spin-stabilized projectile will experience a spin-induced sideways component, due to a gyroscopic phenomenon known as "yaw of repose." For a right hand (clockwise) direction of rotation this component will always be to the right. For a left hand (counterclockwise) direction of rotation this component will always be to the left.
Quasi-experimental design Design Quasi-experimental_design > Design As such, random assignment ensures that both the experimental and control groups are equivalent. In a quasi-experimental design, assignment to a given treatment condition is based on something other than random assignment. Depending on the type of quasi-experimental design, the researcher might have control over assignment to the treatment condition but use some criteria other than random assignment (e.g., a cutoff score) to determine which participants receive the treatment, or the researcher may have no control over the treatment condition assignment and the criteria used for assignment may be unknown.
Thiosilanes Summary Thiosilanes As a family thiosilanes refers to compounds of the form RSSiR'H2 with a S-Si bond between organic groups. == References ==
Avoidance behavior Comorbidity Avoidant_personality_disorder > Signs and symptoms > Comorbidity AvPD is reported to be especially prevalent in people with anxiety disorders, although estimates of comorbidity vary widely due to differences in (among others) diagnostic instruments. Research suggests that approximately 10–50% of people who have panic disorder with agoraphobia have avoidant personality disorder, as well as about 20–40% of people who have social anxiety disorder. In addition to this, AvPD is more prevalent in people who have comorbid social anxiety disorder and generalised anxiety disorder than in those who have only one of the aforementioned conditions.Some studies report prevalence rates of up to 45% among people with generalized anxiety disorder and up to 56% of those with obsessive–compulsive disorder. Post-traumatic stress disorder is also commonly comorbid with avoidant personality disorder.Avoidants are prone to self-loathing and, in certain cases, self-harm. Substance use disorders are also common in individuals with AvPD—particularly in regard to alcohol, benzodiazepines, and opioids—and may significantly affect a patient's prognosis.Earlier theorists proposed a personality disorder with a combination of features from borderline personality disorder and avoidant personality disorder, called "avoidant-borderline mixed personality" (AvPD/BPD).
Software standard Summary Software_standard A software standard is a standard, protocol, or other common format of a document, file, or data transfer accepted and used by one or more software developers while working on one or more than one computer programs. Software standards enable interoperability between different programs created by different developers.
Computer code C Computer_programs > Programming paradigms and languages > Imperative languages > C arithmetic on pointers. pointers to functions. bit operations.
PANDAS Mechanism PANDAS > Classification > Mechanism In some rheumatic fever patients, autoantibodies may attack heart tissue, leading to carditis, or cross-react with joints, leading to arthritis. In PANDAS, it is believed that tics and OCD are produced in a similar manner. One part of the brain that may be affected in PANDAS is the basal ganglia, which is believed to be responsible for movement and behavior. It is thought that similar to Sydenham's, the antibodies cross-react with neuronal brain tissue in the basal ganglia to cause the tics and OCD that characterize PANDAS.Whether the group of patients diagnosed with PANDAS have developed tics and OCD through a different mechanism (pathophysiology) than seen in other people diagnosed with TS is unclear. Studies of this hypothesis are inconsistent: the strongest supportive evidence comes from a controlled study of 144 children (Mell et al., 2005), but prospective longitudinal studies have not produced conclusive results, and other studies do not support the hypothesis.
Enzyme kinetics Mechanisms of catalysis Ping_pong_mechanism > Mechanisms of catalysis After binding takes place, one or more mechanisms of catalysis lower the energy of the reaction's transition state by providing an alternative chemical pathway for the reaction. Mechanisms of catalysis include catalysis by bond strain; by proximity and orientation; by active-site proton donors or acceptors; covalent catalysis and quantum tunnelling.Enzyme kinetics cannot prove which modes of catalysis are used by an enzyme. However, some kinetic data can suggest possibilities to be examined by other techniques. For example, a ping–pong mechanism with burst-phase pre-steady-state kinetics would suggest covalent catalysis might be important in this enzyme's mechanism. Alternatively, the observation of a strong pH effect on Vmax but not KM might indicate that a residue in the active site needs to be in a particular ionisation state for catalysis to occur.
Finite-state machine Finite-state machines (automata theory) in theoretical computer science Finite-state_machine > Further reading > Finite-state machines (automata theory) in theoretical computer science Hopkin, David; Moss, Barbara (1976). Automata. New York: Elsevier North-Holland.
Noether current Basic illustrations and background Noether's_Theorem > Basic illustrations and background : 23: 261 Noether's theorem is important, both because of the insight it gives into conservation laws, and also as a practical calculational tool. It allows investigators to determine the conserved quantities (invariants) from the observed symmetries of a physical system. Conversely, it allows researchers to consider whole classes of hypothetical Lagrangians with given invariants, to describe a physical system.
Hash-based cryptography Summary Hash-based_cryptography Hash-based cryptography is the generic term for constructions of cryptographic primitives based on the security of hash functions. It is of interest as a type of post-quantum cryptography. So far, hash-based cryptography is used to construct digital signatures schemes such as the Merkle signature scheme, zero knowledge and computationally integrity proofs, such as the zk-STARK proof system and range proofs over issued credentials via the HashWires protocol. Hash-based signature schemes combine a one-time signature scheme, such as a Lamport signature, with a Merkle tree structure.
Optical spectroscopy Nature of the interaction Atomic_spectral_line > Classification of methods > Nature of the interaction The coherence can be disrupted by other interactions, such as particle collisions and energy transfer, and so often require high intensity radiation to be sustained. Nuclear magnetic resonance (NMR) spectroscopy is a widely used resonance method, and ultrafast laser spectroscopy is also possible in the infrared and visible spectral regions. Nuclear spectroscopy are methods that use the properties of specific nuclei to probe the local structure in matter, mainly condensed matter, molecules in liquids or frozen liquids and bio-molecules. Quantum logic spectroscopy is a general technique used in ion traps which enables precision spectroscopy of ions with internal structures that preclude laser cooling, state manipulation, and detection. Quantum logic operations enable a controllable ion to exchange information with a co-trapped ion that has a complex or unknown electronic structure.
Zhong Lin Wang Science and technology of nanogenerators Zhong_Lin_Wang > Career > Science and technology of nanogenerators Wang introduced the hybrid cell in 2009 for simultaneously harvesting two or more different types of energy, such as solar and mechanical energy. Besides multiple types of energy, the hybrid cell also includes the case of using two different approaches to harvest the same type of energy. Pyroelectric nanogenerator.
Thermite Summary Thermite_reaction Thermite () is a pyrotechnic composition of metal powder and metal oxide. When ignited by heat or chemical reaction, thermite undergoes an exothermic reduction-oxidation (redox) reaction. Most varieties are not explosive, but can create brief bursts of heat and high temperature in a small area.
Ribosome biogenesis Prokaryotes Ribosome_biogenesis > Prokaryotes Instead, they will negatively feedback and bind to their own mRNA, repressing r-protein synthesis. Note that r-proteins preferentially bind to their complementary rRNA if it is present, rather than mRNA. The ribosome operons also include the genes for RNA polymerase and elongation factors (used in RNA translation). Regulation of all of these genes at once illustrate the coupling between transcription and translation in prokaryotes.
Host tropism Mechanisms Host_tropism > Mechanisms A pathogen displays tropism for a specific host if it can interact with the host cells in a way that supports pathogenic growth and infection. Various factors affect the ability of a pathogen to infect a particular cell, including: the structure of the cell's surface receptors; the availability of transcription factors that can identify pathogenic DNA or RNA; the ability of the cells and tissue to support viral or bacterial replication; and the presence of physical or chemical barriers within the cells and throughout the surrounding tissue.
Intel iAPX 432 Garbage collection Intel_iAPX_432 > Architecture > Garbage collection Software running on the 432 does not need to explicitly deallocate objects that are no longer needed. Instead, the microcode implements part of the marking portion of Edsger Dijkstra's on-the-fly parallel garbage collection algorithm (a mark-and-sweep style collector). The entries in the system object table contain the bits used to mark each object as being white, black, or grey as needed by the collector. The iMAX 432 operating system includes the software portion of the garbage collector.
Ethylene Oxide Addition of water and alcohols Ethylene_Oxide > Chemical properties > Addition of water and alcohols Aqueous solutions of ethylene oxide are rather stable and can exist for a long time without any noticeable chemical reaction, but adding a small amount of acid, such as strongly diluted sulfuric acid, immediately leads to the formation of ethylene glycol, even at room temperature: (CH2CH2)O + H2O → HO–CH2CH2–OHThe reaction also occurs in the gas phase, in the presence of a phosphoric acid salt as a catalyst.The reaction is usually carried out at about 60 °C (140 °F) with a large excess of water, in order to prevent the reaction of the formed ethylene glycol with ethylene oxide that would form di- and triethylene glycol: 2 (CH2CH2)O + H2O → HO–CH2CH2–O–CH2CH2–OH3 (CH2CH2)O + H2O → HO–CH2CH2–O–CH2CH2–O–CH2CH2–OHThe use of alkaline catalysts may lead to the formation of polyethylene glycol: n (CH2CH2)O + H2O → HO–(–CH2CH2–O–)n–HReactions with alcohols proceed similarly yielding ethylene glycol ethers: (CH2CH2)O + C2H5OH → HO–CH2CH2–OC2H52 (CH2CH2)O + C2H5OH → HO–CH2CH2–O–CH2CH2–OC2H5Reactions with lower alcohols occur less actively than with water and require more severe conditions, such as heating to 160 °C (320 °F) and pressurizing to 3 MPa (440 psi) and adding an acid or alkali catalyst. Reactions of ethylene oxide with fatty alcohols proceed in the presence of sodium metal, sodium hydroxide or boron trifluoride and are used for the synthesis of surfactants.
Solver Solver types Solver > Solver types Types of problems with existing dedicated solvers include: Linear and non-linear equations. In the case of a single equation, the "solver" is more appropriately called a root-finding algorithm. Systems of linear equations. Nonlinear systems.
Minimum inhibitory concentration Summary Minimum_inhibitory_concentration In diagnostic labs, MIC test results are used to grade microbes as "S" (susceptible or responding to a standard dosing regimen), "I" (intermediate or requiring increased exposure) or "R" (resistant). These grades are assigned based on agreed upon values called breakpoints. Breakpoints are published by standards development organizations such as the U.S.
Delay slot Branch delay slots Delayed_branch_logic > Branch delay slots Another side effect is that special handling is needed when managing breakpoints on instructions as well as stepping while debugging within branch delay slot. The ideal number of branch delay slots in a particular pipeline implementation is dictated by the number of pipeline stages, the presence of register forwarding, what stage of the pipeline the branch conditions are computed, whether or not a branch target buffer (BTB) is used and many other factors. Software compatibility requirements dictate that an architecture may not change the number of delay slots from one generation to the next. This inevitably requires that newer hardware implementations contain extra hardware to ensure that the architectural behavior is followed despite no longer being relevant.
Reo Coordination Language Semantics Reo_Coordination_Language > Semantics The semantics of a Reo circuit is a formal description of its behavior. Various semantics for Reo exist.Historically the first semantics of Reo was based on the coalgebraic notion of streams (i.e., infinite sequences). This semantics is based on the concept of a timed data stream, which is a pair consisting of a stream of data items and a stream of monotonically increasing time stamps (real numbers).
Glossary of mechanical engineering A Glossary_of_mechanical_engineering > A The unifying abstract concept is that a certain amount of difference allows for some known factor of compensation or interference. For example, an area of excess metal may be left because it is needed to complete subsequent machining.
Integrated information theory Related papers Integrated_information_theory > External links > Related papers doi:10.1038/nrn.2016.44. PMID 27225071. S2CID 21347087.
Metal cluster compound Transition metal carbonyl clusters Metal_cluster_compound > Transition metal carbonyl clusters Many metal carbonyl clusters contain ligands aside from CO. For example, the CO ligand can be replaced with myriad alternatives such as phosphines, isocyanides, alkenes, hydride, etc. Some carbonyl clusters contain two or more metals. Others contain carbon vertices.
Activated alumina Catalyst applications Activated_alumina > Uses > Catalyst applications Activated alumina is used for a wide range of adsorbent and catalyst applications including the adsorption of catalysts in polyethylene production, in hydrogen peroxide production, as a selective adsorbent for many chemicals including arsenic, fluoride, in sulfur removal from fluid streams (Claus Catalyst process).
Music of the spheres Harmonices Mundi Music_of_the_spheres > Harmonices Mundi Finally, after a discussion on astrology in book five, Kepler ends Harmonices by describing his third law, which states that — for any planet — the cube of the semi-major axis of its elliptical orbit is proportional to the square of its orbital period.In the final book of Harmonices, Kepler explains how the ratio of the maximum and minimum angular speeds of each planet (i.e., its speeds at the perihelion and aphelion) is very nearly equivalent to a consonant musical interval. Furthermore, the ratios between these extreme speeds of the planets compared against each other create even more mathematical harmonies. These speeds explain the eccentricity of the orbits of the planets in a natural way that appealed to Kepler's religious beliefs in a heavenly creator.While Kepler did believe that the harmony of the worlds was inaudible, he related the motions of the planets to musical concepts in book four of Harmonices.
World energy resources Renewable resources Energy_resources > Renewable resources Most of earth's available energy resources are renewable resources. Renewable resources account for more than 93 percent of total U.S. energy reserves. Annual renewable resources were multiplied times thirty years for comparison with non-renewable resources. In other words, if all non-renewable resources were uniformly exhausted in 30 years, they would only account for 7 percent of available resources each year, if all available renewable resources were developed.
Thermo mechanical fatigue Fatigue Thermo-mechanical_fatigue > Models > Damage accumulation model > Fatigue The life from fatigue is calculated for isothermal loading conditions. It is dominated by the strain applied to the specimen. Δ ϵ m 2 = C ( 2 N f f a t i g u e ) d {\displaystyle {\frac {\Delta \epsilon _{m}}{2}}=C(2N_{f}^{fatigue})^{d}} where C {\displaystyle C} and d {\displaystyle d} are material constants found through isothermal testing. Note that this term does not account for temperature effects. The effects of temperature are treated in the oxidation and creep terms..
Futile cycle Summary Futile_cycle For example, if glycolysis and gluconeogenesis were to be active at the same time, glucose would be converted to pyruvate by glycolysis and then converted back to glucose by gluconeogenesis, with an overall consumption of ATP. Futile cycles may have a role in metabolic regulation, where a futile cycle would be a system oscillating between two states and very sensitive to small changes in the activity of any of the enzymes involved.
Infrastructural power Building infrastructural power Infrastructural_power > Building infrastructural power Ensure the literacy of the population, which provides a means of informing the public about state laws and allows for a collective awareness of state power. Produce a system of weights and measures and a currency to facilitate the exchange of goods. The state must be able to guarantee that these goods ultimately have value. Provide effective systems of communication and transportation.
Use of force continuum Example model Use_of_force_continuum > Example model Lethal force/Deadly force – a force with a high probability of causing death or serious bodily injury. Serious bodily injury includes unconsciousness, protracted or obvious physical disfigurement, or protracted loss of or impairment to the function of a bodily member, organ, or the mental faculty. A firearm is the most widely recognized lethal or deadly force weapon, however, an automobile or weapon of opportunity could also be defined as a deadly force utility.The U.S.
Magnetic flux Summary Magnetic_flux In physics, specifically electromagnetism, the magnetic flux through a surface is the surface integral of the normal component of the magnetic field B over that surface. It is usually denoted Φ or ΦB. The SI unit of magnetic flux is the weber (Wb; in derived units, volt–seconds), and the CGS unit is the maxwell. Magnetic flux is usually measured with a fluxmeter, which contains measuring coils, and it calculates the magnetic flux from the change of voltage on the coils.
Hierarchical control system Overview Hierarchical_control_system > Overview A human-built system with complex behavior is often organized as a hierarchy. For example, a command hierarchy has among its notable features the organizational chart of superiors, subordinates, and lines of organizational communication. Hierarchical control systems are organized similarly to divide the decision making responsibility.
Mir-181 microRNA precursor Chronic lymphocytic leukemia Mir-181_microRNA_precursor > miR-181 > Chronic lymphocytic leukemia miR-181 may have a regulatory role with tumor suppressors genes of the human chromosome 1. It has been shown that the Tcl1 oncogene is a target of miR-181a in an inhibition relation (downregulated) that would result in an action on the tumor cell growth process. miR-181 expression has a reverse correlation with Tcl1 protein expression.
Small interfering RNA Therapies Small_interfering_RNA > Therapies Another advantage is that, unlike small molecule and monoclonal antibodies that need to recognize specific conformation of a protein, siRNA functions by Watson-Crick basepairing with mRNA. Therefore, any target molecule that needs to be treated with high affinity and specificity can be selected if the right nucleotide sequence is available. One of the biggest challenges researchers needed to overcome was the identification and establishment of a delivery system through which the therapies would enter the body.
Sessile serrated adenoma Treatment Sessile_serrated_adenoma > Treatment Complete removal of a SSL is considered curative. Several SSLs confer a higher risk of subsequently finding colorectal cancer and warrant more frequent surveillance. The surveillance guidelines are the same as for other colonic adenomas. The surveillance interval is dependent on (1) the number of adenomas, (2) the size of the adenomas, and (3) the presence of high-grade microscopic features.
Earthquake prediction Characteristic earthquakes Earthquake_prediction > Prediction methods > Trends > Characteristic earthquakes The most studied earthquake faults (such as the Nankai megathrust, the Wasatch fault, and the San Andreas fault) appear to have distinct segments. The characteristic earthquake model postulates that earthquakes are generally constrained within these segments. As the lengths and other properties of the segments are fixed, earthquakes that rupture the entire fault should have similar characteristics. These include the maximum magnitude (which is limited by the length of the rupture), and the amount of accumulated strain needed to rupture the fault segment.
Quantum key distribution Deprecation of quantum key distributions from governmental institutions Quantum_key_distribution > Deprecation of quantum key distributions from governmental institutions The sensitivity to an eavesdropper as the theoretical basis for QKD security claims also shows that denial of service is a significant risk for QKD.In response to problem 1 above, attempts to deliver authentication keys using post-quantum cryptography (or quantum-resistant cryptography) have been proposed worldwide. On the other hand, quantum-resistant cryptography is cryptography belonging to the class of computational security. In 2015, a research result was already published that "sufficient care must be taken in implementation to achieve information-theoretic security for the system as a whole when authentication keys that are not information-theoretic secure are used" (when the authentication key is not information-theoretic secure (If the authentication key is not information-theoretically secure, an attacker can break it to bring all classical and quantum communications under control and relay them to launch a man-in-the-middle attack). Ericsson, a private company, also cites and points out the above problems and then presents a report that it may not be able to support the Zero trust security model, which is a recent trend in network security technology.
Newtonian motivations for general relativity The geodesic and field equations for circular orbits Newtonian_foundation_of_general_relativity > Two nearby particles in a radial gravitational field > Newtonian mechanics for circular orbits > The geodesic and field equations for circular orbits This is represented by the "field equation" R = G M r 3 {\displaystyle R={GM \over {r^{3}}}} In this example, the field equation is simply a statement of the Newtonian concept that centripetal force is equal to gravitational force for circular orbits. We refer to this expression as a field equation in order to highlight the similarities with the Einstein field equation. This equation is in a much different form than Gauss's law, which is the usual characterization of the field equation in Newtonian mechanics.
Trigeminal neuralgia Causes Trigeminal_neuralgia > Causes This type of injury may rarely be caused by an aneurysm (an outpouching of a blood vessel); by an AVM (arteriovenous malformation); by a tumor; such as an arachnoid cyst or meningioma in the cerebellopontine angle; or by a traumatic event, such as a car accident.Short-term peripheral compression is often painless. Persistent compression results in local demyelination with no loss of axon potential continuity. Chronic nerve entrapment results in demyelination primarily, with progressive axonal degeneration subsequently.
A-star algorithm Implementation details A-star_algorithm > Description > Implementation details At the end of the search, these references can be used to recover the optimal path. If these references are being kept then it can be important that the same node doesn't appear in the priority queue more than once (each entry corresponding to a different path to the node, and each with a different cost). A standard approach here is to check if a node about to be added already appears in the priority queue.
Jitterlyzer Timing Jitterlyzer > Jitter measurements > Timing Jitter Histogram - This routine is performed on real-life traffic. It selects the zero-crossing voltage in the incoming data. It then counts the number of transitions of the high-speed serial signal as a function of phase positions. A histogram of number of hits versus delay is then plotted.
Spoiler (car) Active spoilers Spoiler_(car) > Active spoilers An active spoiler is one that dynamically adjusts while the vehicle is in operation based on conditions presented, changing the spoiling effect, intensity, or other performance attributes. Found most often on sports cars and other passenger cars, the most common form is a rear spoiler that retracts and hides partially or entirely into the rear of the vehicle, then extends upwards when the vehicle exceeds a specific speed, such as the active spoiler in the Bugatti Veyron. Active front spoilers have been implemented on certain models as well, in which the front spoiler or air dam extends further toward the road below to reduce drag at high speed. In most cases, the deployment of the spoiler is achieved with an electric motor controlled automatically by the onboard computer or other electronics, usually based on vehicle speed, driver setting, or other inputs.
Decidability (logic) Some decidable theories Decidability_(logic) > Some decidable theories Some decidable theories include (Monk 1976, p. 234): The set of first-order logical validities in the signature with only equality, established by Leopold Löwenheim in 1915. The set of first-order logical validities in a signature with equality and one unary function, established by Ehrenfeucht in 1959. The first-order theory of the natural numbers in the signature with equality and addition, also called Presburger arithmetic.
Spectrum analyser Vibration spectrum analyzer Spectral_analyzer > Vibration spectrum analyzer A vibration spectrum analyzer allows to analyze vibration amplitudes at various component frequencies, In this way, vibration occurring at specific frequencies can be identified and tracked. Since particular machinery problems generate vibration at specific frequencies, machinery faults can be detected or diagnosed. Vibration Spectrum Analyzers use the signal from different types of sensor, such as: accelerometers, velocity transducers and proximity sensors. The uses of a vibration spectrum analyzer in machine condition monitoring allows to detect and identify machine faults such as: rotor imbalance, shaft misalignment, mechanical looseness, bearing defects, among others. Vibration analysis can also be used in structures to identify structural resonances or to perform modal analysis.
Temporal feedback Biological examples Temporal_feedback > Biological examples The studies on morphogenesis of limb buds have been focused on one particular axis of limb bud. However it has long been noted that zone of polarizing activity (ZPA) requires maintenance of apical ectodermal ridge (AER). The dependence of ZPA on ARE indicates the linkage between them.
Fluent (artificial intelligence) Summary Fluent_(artificial_intelligence) Some fluents can be represented as functions in a different way. For example, the position of a box can be represented by a function o n ( b o x , t ) {\displaystyle on(box,t)} whose value is the object the box is standing on at time t {\displaystyle t} . Conditions that can be represented in this way are called functional fluents. Statements about the values of such functions can be given in first order logic with equality using literals such as o n ( b o x , t ) = t a b l e {\displaystyle on(box,t)=table} . Some fluents are represented this way in the situation calculus.
MIMO-OFDM Operation MIMO-OFDM > Operation DFTs may be applied to composite OFDM signals, avoiding the need for the banks of oscillators and demodulators associated with individual subcarriers. Fast Fourier transforms are numerical algorithms used by computers to perform DFT calculations.FFTs also enable OFDM to make efficient use of bandwidth. The subchannels must be spaced apart in frequency just enough to ensure that their time-domain waveforms are orthogonal to each other.
Algorithmic synthesis History High-level_synthesis > History First generation behavioral synthesis was introduced by Synopsys in 1994 as Behavioral Compiler and used Verilog or VHDL as input languages. The abstraction level used was partially timed (clocked) processes. Tools based on behavioral Verilog or VHDL were not widely adopted in part because neither languages nor the partially timed abstraction were well suited to modeling behavior at a high level.
Isotopes of roentgenium Nuclear isomerism Roentgenium-276 > Isotopes and nuclear properties > Nuclear isomerism 274RgTwo atoms of 274Rg have been observed in the decay chain of 278Nh. They decay by alpha emission, emitting alpha particles with different energies, and have different lifetimes. In addition, the two entire decay chains appear to be different.
Work flow Beginnings in manufacturing Workflow_management > Historical development > Beginnings in manufacturing The modern history of workflows can be traced to Frederick Taylor and Henry Gantt, although the term "workflow" was not in use as such during their lifetimes. One of the earliest instances of the term "work flow" was in a railway engineering journal from 1921.Taylor and Gantt launched the study of the deliberate, rational organization of work, primarily in the context of manufacturing. This gave rise to time and motion studies. Related concepts include job shops and queuing systems (Markov chains).The 1948 book Cheaper by the Dozen introduced the emerging concepts to the context of family life.
Chronic headaches Old headaches Chronic_headaches > Diagnosis > Old headaches Old headaches are usually primary headaches and are not dangerous. They are most often caused by migraines or tension headaches. Migraines are often unilateral, pulsing headaches accompanied by nausea or vomiting. There may be an aura (visual symptoms, numbness or tingling) 30–60 minutes before the headache, warning the person of a headache.
Hydrostatic drive Force and torque multiplication Hydraulic_circuit > Force and torque multiplication A fundamental feature of hydraulic systems is the ability to apply force or torque multiplication in an easy way, independent of the distance between the input and output, without the need for mechanical gears or levers, either by altering the effective areas in two connected cylinders or the effective displacement (cc/rev) between a pump and motor. In normal cases, hydraulic ratios are combined with a mechanical force or torque ratio for optimum machine designs such as boom movements and track drives for an excavator.
Reaction intermediate Methane chlorination Reaction_product > Common reaction intermediates > Radicals > Methane chlorination The full reaction is a free radical propagation reaction which is filled out in detail below. Initiation: This reaction can occur by thermolysis (heating) or photolysis (absorption of light) leading to the breakage of a molecular chlorine bond. Cl − Cl → h ν Cl ⋅ + Cl ⋅ {\displaystyle {\ce {Cl-Cl -> Cl.
Data Presentation Architecture Terminology Data_presentation > Terminology Two primary types of information displays are tables and graphs. A table contains quantitative data organized into rows and columns with categorical labels.
Schema for vertical declining dials Basic calculation Schema_for_vertical_declining_dials > Basic calculation AV- Angle to vertical? -this is used to fix a starting point, in the final stage of laying out equal hours with a protractor. With a calculator this can be easily be derived from the SD and DL, when using compass and ruler it is a construction base line.
Electrochemical RAM Principle Electrochemical_RAM > Synaptic function > Principle For ECRAM cells, an additional line is added at each row to write the cells during programming cycles, thereby yielding a pseudo-crossbar architecture. In the field of artificial intelligence (AI), deep neural networks (DNN) are used for classification and learning tasks, relying on a large number of matrix-multiply operations. Therefore, analog compute with NVM technology for such tasks are extremely attractive. ECRAM cells are uniquely positioned for use in analog deep learning accelerators due to their inherent deterministic and symmetric programming nature when compared to other devices such as resistive RAM (ReRAM or RRAM) and phase-change memory (PCM).
Rock cycle Transition to sedimentary rock Rock_cycle > Transition to sedimentary rock Rocks exposed to the atmosphere are variably unstable and subject to the processes of weathering and erosion. Weathering and erosion break the original rock down into smaller fragments and carry away dissolved material. This fragmented material accumulates and is buried by additional material. While an individual grain of sand is still a member of the class of rock it was formed from, a rock made up of such grains fused together is sedimentary.
Universal parabolic constant Summary Universal_parabolic_constant The universal parabolic constant is a mathematical constant. It is defined as the ratio, for any parabola, of the arc length of the parabolic segment formed by the latus rectum to the focal parameter. The focal parameter is twice the focal length. The ratio is denoted P. In the diagram, the latus rectum is pictured in blue, the parabolic segment that it forms in red and the focal parameter in green.
DnaA Summary DnaA In addition to the DnaA protein, its concentration, binding to DnaA-boxes, and binding of ATP or ADP, we will cover the regulation of the DnaA gene, the unique characteristics of the DnaA gene expression, promoter strength, and translation efficiency. The onset of the initiation phase of DNA replication is determined by the concentration of DnaA. DnaA accumulates during growth and then triggers the initiation of replication.
Kepler-452b Observation and exploration Kepler-452b > Observation and exploration Kepler-452b is 1,800 light-years (550 parsecs) from Earth. The fastest current spacecraft, the New Horizons uncrewed probe that passed Pluto in July 2015, travels at just 56,628 km/h (15,730 m/s; 35,187 mph; 0.00037853 AU/h). At that speed, it would take a spacecraft about 26 million years to reach Kepler-452b from Earth, if it was going in that direction.
Gaussian density Operations and functions of normal variables Normal_cumulative_distribution_function > Related distributions > Operations and functions of normal variables The probability density, cumulative distribution, and inverse cumulative distribution of any function of one or more independent or correlated normal variables can be computed with the numerical method of ray-tracing (Matlab code). In the following sections we look at some special cases.
Angular jerk Physiological effects and human perception Angular_jerk > Physiological effects and human perception Excessive jerk may also result in an uncomfortable ride, even at levels that do not cause injury. Engineers expend considerable design effort minimizing "jerky motion" on elevators, trams, and other conveyances. For example, consider the effects of acceleration and jerk when riding in a car: Skilled and experienced drivers can accelerate smoothly, but beginners often provide a jerky ride.
Tobacco abuse Chemical carcinogens Smoker's_Paradox > Mechanism > Chemical carcinogens The acrolein-guanine adduct induces mutations during DNA copying and thus causes cancers in a manner similar to PAHs. However, acrolein is 1000 times more abundant than PAHs in cigarette smoke and is able to react as is, without metabolic activation. Acrolein has been shown to be a mutagen and carcinogen in human cells.
Observational error Imperfect calibration Systematic_bias > Sources > Sources of systematic error > Imperfect calibration Distance measured by radar will be systematically overestimated if the slight slowing down of the waves in air is not accounted for. Incorrect zeroing of an instrument is an example of systematic error in instrumentation. Systematic errors may also be present in the result of an estimate based upon a mathematical model or physical law. For instance, the estimated oscillation frequency of a pendulum will be systematically in error if slight movement of the support is not accounted for.
Underfitting Machine learning Overfitting > Machine learning For example, it is nontrivial to directly compare the complexity of a neural net (which can track curvilinear relationships) with m parameters to a regression model with n parameters.Overfitting is especially likely in cases where learning was performed too long or where training examples are rare, causing the learner to adjust to very specific random features of the training data that have no causal relation to the target function. In this process of overfitting, the performance on the training examples still increases while the performance on unseen data becomes worse. As a simple example, consider a database of retail purchases that includes the item bought, the purchaser, and the date and time of purchase.
Oscilloscope Bandwidth Storage_oscilloscope > Features and uses > Bandwidth A sampling oscilloscope can display signals of considerably higher frequency than the sampling rate if the signals are exactly, or nearly, repetitive. It does this by taking one sample from each successive repetition of the input waveform, each sample being at an increased time interval from the trigger event. The waveform is then displayed from these collected samples. This mechanism is referred to as "equivalent-time sampling". Some oscilloscopes can operate in either this mode or in the more traditional "real-time" mode at the operator's choice.
Pyroptosis Metabolic disorder Pyroptosis > Clinical relevance > Metabolic disorder The level of expression of NLRP3 inflammasome and caspase-1 has a direct relation to the severity of several metabolic syndromes, such as obesity and type II diabetic mellitus (T2DM). This is because the subsequent production level of IL-1β and IL-18, cytokines that impair the secretion of insulin, is affected by the activity of caspase-1. Glucose uptake level is then diminished, and the condition is known as insulin resistance. The condition is further accelerated by the IL-1β-induced destruction of pancreatic β cells.
Message queuing service Benefits Message_queuing_service > Benefits A message queueing service also creates new value by providing reduced costs, enhanced performance and reliability. In order to provide those benefits, a message queueing service leverages cloud computing resources such as storage, network, memory and processing capacity. By using virtually unlimited cloud computing resources, a message queueing service provides an internet scale messaging platform.
Flywheel energy storage General Flywheel_energy_storage > Physical characteristics > General Compared with other ways to store electricity, FES systems have long lifetimes (lasting decades with little or no maintenance; full-cycle lifetimes quoted for flywheels range from in excess of 105, up to 107, cycles of use), high specific energy (100–130 W·h/kg, or 360–500 kJ/kg), and large maximum power output. The energy efficiency (ratio of energy out per energy in) of flywheels, also known as round-trip efficiency, can be as high as 90%. Typical capacities range from 3 kWh to 133 kWh. Rapid charging of a system occurs in less than 15 minutes. The high specific energies often cited with flywheels can be a little misleading as commercial systems built have much lower specific energy, for example 11 W·h/kg, or 40 kJ/kg.
Ant colony optimization Algorithm and formula Ant_colony_optimization_algorithm > Algorithm and formula In the ant colony optimization algorithms, an artificial ant is a simple computational agent that searches for good solutions to a given optimization problem. To apply an ant colony algorithm, the optimization problem needs to be converted into the problem of finding the shortest path on a weighted graph. In the first step of each iteration, each ant stochastically constructs a solution, i.e. the order in which the edges in the graph should be followed.
Multiplication by juxtaposition Notation and terminology Implied_multiplication > Notation and terminology In vector multiplication, there is a distinction between the cross and the dot symbols. The cross symbol generally denotes the taking a cross product of two vectors, yielding a vector as its result, while the dot denotes taking the dot product of two vectors, resulting in a scalar.In computer programming, the asterisk (as in 5*2) is still the most common notation. This is due to the fact that most computers historically were limited to small character sets (such as ASCII and EBCDIC) that lacked a multiplication sign (such as ⋅ or ×), while the asterisk appeared on every keyboard.
Oxyanion Acid–base properties Oxyanion > Acid–base properties In forming this ion, the phosphite ion is behaving as a Lewis base and donating a pair of electrons to the Lewis acid, H+. As mentioned above, a condensation reaction is also an acid–base reaction. In many systems, both protonation and condensation reactions can occur.
Memory organisation Summary Memory_organisation There are several ways to organise memories with respect to the way they are connected to the cache: one-word-wide memory organisation wide memory organisation interleaved memory organisation independent memory organisation
Covariance and contravariance of vectors Algebra and geometry Covariant_vector > Algebra and geometry In category theory, there are covariant functors and contravariant functors. The assignment of the dual space to a vector space is a standard example of a contravariant functor. Some constructions of multilinear algebra are of "mixed" variance, which prevents them from being functors. In differential geometry, the components of a vector relative to a basis of the tangent bundle are covariant if they change with the same linear transformation as a change of basis.
Propeller governor Purpose Constant_speed_unit > Purpose If the propeller blade angle is set to give good takeoff and climb performance, the propeller will be inefficient in cruising flight because the blade will be at too low an angle of attack. In contrast, a propeller set for good cruise performance may stall at low speeds, because the angle of attack is too high. A propeller with adjustable blade angle is more efficient over a range of conditions.
Inverse trigonometric functions Finding the angle of a right triangle Arc_(function_prefix) > Applications > Finding the angle of a right triangle For example, suppose a roof drops 8 feet as it runs out 20 feet. The roof makes an angle θ with the horizontal, where θ may be computed as follows: θ = arctan ⁡ ( opposite adjacent ) = arctan ⁡ ( rise run ) = arctan ⁡ ( 8 20 ) ≈ 21.8 ∘ . {\displaystyle \theta =\arctan \left({\frac {\text{opposite}}{\text{adjacent}}}\right)=\arctan \left({\frac {\text{rise}}{\text{run}}}\right)=\arctan \left({\frac {8}{20}}\right)\approx 21.8^{\circ }\,.}
Free piston engine Generators Free-piston_engine > Modern applications > Generators The engine is easily modified to operate under various fuels including hydrogen, natural gas, ethanol, gasoline and diesel. A two-cylinder FPEG is inherently balanced.Toyota claims a thermal-efficiency rating of 42% in continuous use, greatly exceeding today's average of 25-30%. Toyota demonstrated a 24 inch long by 2.5 inch in diameter unit producing 15 hp (greater than 11 kW).
Automated planning and scheduling Conditional planning Computer_planning > Algorithms for planning > Conditional planning A major advantage of conditional planning is the ability to handle partial plans. An agent is not forced to plan everything from start to finish but can divide the problem into chunks. This helps to reduce the state space and solves much more complex problems.
Genetic engineering in agriculture Medicine Genetic_engineering_in_agriculture > Applications > Medicine The work was widely condemned as unethical, dangerous, and premature. Currently, germline modification is banned in 40 countries. Scientists that do this type of research will often let embryos grow for a few days without allowing it to develop into a baby.Researchers are altering the genome of pigs to induce the growth of human organs, with the aim of increasing the success of pig to human organ transplantation. Scientists are creating "gene drives", changing the genomes of mosquitoes to make them immune to malaria, and then looking to spread the genetically altered mosquitoes throughout the mosquito population in the hopes of eliminating the disease.
Gradient-based optimization Choosing the step size and descent direction Gradient_ascent > Description > Choosing the step size and descent direction The problem is that evaluating the second term in square brackets requires evaluating ∇ F ( a n − t γ n p n ) {\displaystyle \nabla F(\mathbf {a} _{n}-t\gamma _{n}\mathbf {p} _{n})} , and extra gradient evaluations are generally expensive and undesirable. Some ways around this problem are: Forgo the benefits of a clever descent direction by setting p n = ∇ F ( a n ) {\displaystyle \mathbf {p} _{n}=\nabla F(\mathbf {a_{n}} )} , and use line search to find a suitable step-size γ n {\displaystyle \gamma _{n}} , such as one that satisfies the Wolfe conditions. A more economic way of choosing learning rates is backtracking line search, a method that has both good theoretical guarantees and experimental results.
Map winding number Example Map_winding_number > Example If f {\displaystyle f} is a rotation by 2 π N {\displaystyle 2\pi N} (where 0 < N < 1 {\displaystyle 0
Storage engine Database indexing Storage_engine > Design considerations > Database indexing Indexing is a technique some storage engines use for improving database performance. The many types of indexes share the common property that they reduce the need to examine every entry when running a query. In large databases, this can reduce query time/cost by orders of magnitude. The simplest form of index is a sorted list of values that can be searched using a binary search with an adjacent reference to the location of the entry, analogous to the index in the back of a book.
Adobe Edge Inspect Adobe Edge Code Adobe_Edge_Inspect > Applications > Adobe Edge Code A code-based HTML editor, Edge Code is designed to complement the other applications in the suite. It is built on the open-source Brackets app, which Adobe launched in June 2012. Rather than replacing Brackets, Edge Code is designed to make it more accessible, and integrate its functionality into existing Adobe applications. As with Edge Reflow, Edge Code is available as a public preview, launched alongside the announcement of the Edge suite. In November 2014 Adobe announced development of Code is discontinued and all Adobe's efforts will go into Brackets.
Etruscan numerals Digits Etruscan_numerals > Digits The Etruscan numerical system included the following digits with known values: (With the proper Unicode font installed, the first two rows should look the same.) Examples are known of larger numbers, but it is unknown which digit represents which numeral. Most numbers were written with "additive notation", namely by writing digits that added to the desired number, from higher to lower value.
Mechanical designer Structural analysis Mechanical_design > Subdisciplines > Structural analysis Fatigue failure occurs because of imperfections in the object: a microscopic crack on the surface of the object, for instance, will grow slightly with each cycle (propagation) until the crack is large enough to cause ultimate failure.Failure is not simply defined as when a part breaks, however; it is defined as when a part does not operate as intended. Some systems, such as the perforated top sections of some plastic bags, are designed to break. If these systems do not break, failure analysis might be employed to determine the cause.
Rorschach inkblot test Determinants Rorschach_inkblot_test > Method > Features or categories > Determinants Systems for Rorschach scoring generally include a concept of "determinants": These are the factors that contribute to establishing the similarity between the inkblot and the subject's content response about it. They can also represent certain basic experiential-perceptual attitudes, showing aspects of the way a subject perceives the world. Rorschach's original work used only form, color and movement as determinants.
Symmetry group Introduction Point_group_symmetry > Introduction We consider the "objects" possessing symmetry to be geometric figures, images, and patterns, such as a wallpaper pattern. For symmetry of physical objects, one may also take their physical composition as part of the pattern. (A pattern may be specified formally as a scalar field, a function of position with values in a set of colors or substances; as a vector field; or as a more general function on the object.) The group of isometries of space induces a group action on objects in it, and the symmetry group Sym(X) consists of those isometries which map X to itself (as well as mapping any further pattern to itself).
Turbofan engines Bypass ratio Low_bypass_turbofan > Principles > Bypass ratio At the same time gross and net thrusts increase, but by different amounts. There is considerable potential for reducing fuel consumption for the same core cycle by increasing BPR.This is achieved because of the reduction in pounds of thrust per lb/sec of airflow (specific thrust) and the resultant reduction in lost kinetic energy in the jets (increase in propulsive efficiency).If all the gas power from a gas turbine is converted to kinetic energy in a propelling nozzle, the aircraft is best suited to high supersonic speeds. If it is all transferred to a separate big mass of air with low kinetic energy, the aircraft is best suited to zero speed (hovering).
Software verification and validation Validation vs. verification Software_verification_and_validation > Definitions > Validation vs. verification In other words, software verification ensures that the output of each phase of the software development process effectively carry out what its corresponding input artifact specifies (requirement -> design -> software product), while software validation ensures that the software product meets the needs of all the stakeholders (therefore, the requirement specification was correctly and accurately expressed in the first place). Software verification ensures that "you built it right" and confirms that the product, as provided, fulfills the plans of the developers. Software validation ensures that "you built the right thing" and confirms that the product, as provided, fulfills the intended use and goals of the stakeholders.
Epicenter Epicentral distance Earthquake_location > Epicentral distance During an earthquake, seismic waves propagates in all directions from the hypocenter. Seismic shadowing occurs on the opposite side of the Earth from the earthquake epicenter because the planet's liquid outer core refracts the longitudinal or compressional (P-waves) while it absorbs the transverse or shear waves (S-waves). Outside the seismic shadow zone, both types of wave can be detected but, because of their different velocities and paths through the Earth, they arrive at different times. By measuring the time difference on any seismograph and the distance on a travel-time graph on which the P-wave and S-wave have the same separation, geologists can calculate the distance to the quake's epicenter.
Stevens power law Summary Stevens's_power_law Stevens' power law is an empirical relationship in psychophysics between an increased intensity or strength in a physical stimulus and the perceived magnitude increase in the sensation created by the stimulus. It is often considered to supersede the Weber–Fechner law, which is based on a logarithmic relationship between stimulus and sensation, because the power law describes a wider range of sensory comparisons, down to zero intensity.The theory is named after psychophysicist Stanley Smith Stevens (1906–1973). Although the idea of a power law had been suggested by 19th-century researchers, Stevens is credited with reviving the law and publishing a body of psychophysical data to support it in 1957. The general form of the law is ψ ( I ) = k I a , {\displaystyle \psi (I)=kI^{a},} where I is the intensity or strength of the stimulus in physical units (energy, weight, pressure, mixture proportions, etc.), ψ(I) is the magnitude of the sensation evoked by the stimulus, a is an exponent that depends on the type of stimulation or sensory modality, and k is a proportionality constant that depends on the units used.
Automatic and controlled processes Automatic processes Automatic_and_controlled_processes > Characteristics > Automatic processes When engaged in driving (only with enough practice) one can operate the car almost entirely without conscious awareness. However, more attentional control and decision making are needed when introduced to novel (reference) situations like driving through an unfamiliar town. The process needs to be learned enough that it can be automatic, requiring little conscious thought as to how to do it.
Glucose metabolism disorder Glycogenesis Glucose_metabolism_disorder > Metabolic pathways > Glycogenesis Glycogenesis refers to the process of synthesizing glycogen. In humans, glucose can be converted to glycogen via this process. Glycogen is a highly branched structure, consisting of the core protein Glycogenin, surrounded by branches of glucose units, linked together.
Polynomial matrix Properties Polynomial_matrix > Properties A polynomial matrix over a field with determinant equal to a non-zero element of that field is called unimodular, and has an inverse that is also a polynomial matrix. Note that the only scalar unimodular polynomials are polynomials of degree 0 – nonzero constants, because an inverse of an arbitrary polynomial of higher degree is a rational function. The roots of a polynomial matrix over the complex numbers are the points in the complex plane where the matrix loses rank. The determinant of a matrix polynomial with Hermitian positive-definite (semidefinite) coefficients is a polynomial with positive (nonnegative) coefficients.Note that polynomial matrices are not to be confused with monomial matrices, which are simply matrices with exactly one non-zero entry in each row and column. If by λ we denote any element of the field over which we constructed the matrix, by I the identity matrix, and we let A be a polynomial matrix, then the matrix λI − A is the characteristic matrix of the matrix A. Its determinant, \|λI − A\| is the characteristic polynomial of the matrix A.

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