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Parasympathetic nervous system Cranial nerves Parasympathetic_nerve > Structure > Cranial nerves There are two motors that are part of the oculomotor nerve known as the somatic motor and visceral motor. The somatic motor is responsible for moving the eye in precise motions and for keeping the eye fixated on an object.
Parallel breadth-first search Parallel BFS with shared memory Parallel_breadth-first_search > Parallel BFS with shared memory Compared to parallel BFS with distributed memory, shared memory provides higher memory-bandwidth and lower latency. Because all processors share the memory together, all of them have the direct access to it. Thus, the developers don't need to program message passing process, which is necessary for distributed memory to get data from remote local memory. Therefore, the overhead of messages is avoided.However, the number of vertices in each layer and the number of neighbors of each vertex are shown to be highly irregular, which leads to highly irregular memory accesses and work distribution of BFS.
Contrast-detection autofocus Passive Phase-detection_autofocus > Passive Passive AF systems determine correct focus by performing passive analysis of the image that is entering the optical system. They generally do not direct any energy, such as ultrasonic sound or infrared light waves, toward the subject. (However, an autofocus assist beam of usually infrared light is required when there is not enough light to take passive measurements.) Passive autofocusing can be achieved by phase detection or contrast measurement.
Thymic epithelial cell Diseases Thymic_epithelial_cell > Diseases TECs, as a component of the thymus, play a key role in thymocyte development and self-tolerance, so their dysfunction causes many autoimmune diseases, tumors of immunodeficiencies. Most frequently are occurred epithelial tumors established from TEC and thymocytes - thymomas and thymic carcinoma. Maturation abnormalities of TECs induce chronic inflammatory diseases and decreased count of mTEC and cTEC leads to chronic inflammatory bowel disease (IBD).
Lateral diffusion Prokaryotes Lateral_diffusion > Prokaryotes Some eukaryotic cells also have cell walls, but none that are made of peptidoglycan. The outer membrane of gram negative bacteria is rich in lipopolysaccharides, which are combined poly- or oligosaccharide and carbohydrate lipid regions that stimulate the cell's natural immunity. The outer membrane can bleb out into periplasmic protrusions under stress conditions or upon virulence requirements while encountering a host target cell, and thus such blebs may work as virulence organelles.
Actor model middle history Actor programming languages Actor_model_middle_history > Actor programming languages Bill Kornfeld developed the Ether programming language for the Scientific Community Metaphor in his doctoral dissertation. William Athas and Nanette Boden developed Cantor which is an Actor programming language for scientific computing. Jean-Pierre Briot developed means to extend Smalltalk 80 for Actor computations.
Knowledge graph embedding Translational models with additional embeddings Knowledge_graph_embedding > Models > Geometric models > Translational models with additional embeddings In a similar way, the entity of a fact inderectly determine which is inference path that has to be choose to predict the object of a related triple. CrossE, to do so, learns an additional interaction matrix C {\displaystyle C} , uses the element-wise product to compute the interaction between h {\displaystyle h} and r {\displaystyle r} . Even if, CrossE, does not rely on a neural network architecture, it is shown that this methodology can be encoded in such architecture.
Glossary of genetics (M–Z) S Glossary_of_genetics_(M–Z) > S See also nick; contrast double-strand break. single-stranded Composed of a single, unpaired nucleic acid molecule, i.e. one linear strand of nucleotides sharing a single phosphodiester backbone, as opposed to a duplex of two such strands joined by base pairing. See also single-stranded DNA and single-stranded RNA.
Impulse excitation technique Young's modulus Impulse_excitation_technique > Experimental correlations > Cylindrical rod > Young's modulus E = 1.6067 ( L 3 d 4 ) m f f 2 T ′ {\displaystyle E=1.6067\left({\frac {L^{3}}{d^{4}}}\right)mf_{f}^{2}T'} with T ′ = 1 + 4.939 ( d L ) 2 {\displaystyle T'=1+4.939\left({\frac {d}{L}}\right)^{2}} E the Young's modulus m the mass ff the flexural frequency d the diameter L the length T' the correction factor The correction factor can only be used if L/d ≥ 20!
Multi-junction cell Basics of solar cells Multi-junction_solar_cell > Description > Basics of solar cells Transmitted photons have the potential to give their energy, hν, to an electron if hν ≥ Eg, generating an electron-hole pair. In the depletion region, the drift electric field Edrift accelerates both electrons and holes towards their respective n-doped and p-doped regions (up and down, respectively). The resulting current Ig is called the generated photocurrent.
Planckian distribution Black-body radiation Planck_limits > Black-body radiation The surface of a black body can be modelled by a small hole in the wall of a large enclosure which is maintained at a uniform temperature with opaque walls that, at every wavelength, are not perfectly reflective. At equilibrium, the radiation inside this enclosure is described by Planck's law, as is the radiation leaving the small hole. Just as the Maxwell–Boltzmann distribution is the unique maximum entropy energy distribution for a gas of material particles at thermal equilibrium, so is Planck's distribution for a gas of photons.
Wireless computer network Wireless links Wireless_connection > Wireless links The satellites are stationed in space, typically in geosynchronous orbit 35,400 km (22,000 mi) above the equator. These Earth-orbiting systems are capable of receiving and relaying voice, data, and TV signals.
Linezolid Pneumonia Linezolid > Medical uses > Pneumonia No significant difference appears in treatment success rates between linezolid, glycopeptides, or appropriate beta-lactam antibiotics in the treatment of pneumonia. Clinical guidelines for the treatment of community-acquired pneumonia developed by the American Thoracic Society and the Infectious Diseases Society of America recommend that linezolid be reserved for cases in which MRSA has been confirmed as the causative organism, or when MRSA infection is suspected based on the clinical presentation. The guidelines of the British Thoracic Society do not recommend it as first-line treatment, but rather as an alternative to vancomycin. Linezolid is also an acceptable second-line treatment for community-acquired pneumococcal pneumonia when penicillin resistance is present.U.S.
Sophisticated falsificationism From Hume's problem to non problematic induction Naive_falsificationism > The problem of induction and demarcation > From Hume's problem to non problematic induction This problem is not how to justify a theory or what is the global mechanism for the success of science but only what methodology do we use to pick one theory among theories that are already conjectured. His methodological answer to the latter question is that we pick the theory that is the most tested with the available technology: "the one, which in the light of our critical discussion, appears to be the best so far". By his own account, because only a negative approach was supported by logic, Popper adopted a negative methodology.
Structured kNN Training Structured_kNN > Training Thereby the first step of SkNN training is the construction of described graph from training sequences. There are two special nodes in the graph corresponding to an end and a beginning of sentences. If sequence starts with class `C`, the edge between node `START` and node `C` should be created.
Thermodynamic power cycle A list of thermodynamic processes Thermodynamic_power_cycle > Heat and work > A list of thermodynamic processes The following processes are often used to describe different stages of a thermodynamic cycle: Adiabatic: No energy transfer as heat (Q) during that part of the cycle ( δ Q = 0 {\displaystyle \delta Q=0} ). Energy transfer is considered as work done by the system only. Isothermal: The process is at a constant temperature during that part of the cycle (T=constant, δ T = 0 {\displaystyle \delta T=0} ). Energy transfer is considered as heat removed from or work done by the system.
Self awareness Summary Self_awareness In philosophy of self, self-awareness is the experience of one's own personality or individuality. It is not to be confused with consciousness in the sense of qualia. While consciousness is being aware of one's body and environment, self-awareness is the recognition of that consciousness. Self-awareness is how an individual experiences and understands their own character, feelings, motives, and desires.
Pierre-Émile Martin Martin-Siemens Process Pierre-Émile_Martin > Martin-Siemens Process The process of refining steel in a hearth, as developed by Pierre-Émile Martin, consists of smelting a mixture of cast iron and scrap or ore, then refining it by decarburization, desulfurization and dephosphorization. This method makes it possible to produce fine and alloy steels by adding noble elements. The process employs a gas-heated reverberatory furnace with recovery of the heat from the flue gases as in the Siemens system.
Asynchronous procedure call Summary Asynchronous_procedure_call When the user's reply is received, the service puts it in the object and passes that object to an execution service. Execution service consists of one or more dedicated worker threads and a queue for tasks. Each worker thread reads in a loop task queue and, when a task is retrieved, executes it.
Hash join Hash semi-join Hash_join > Hash semi-join Hash semi-join is used to return the records found in the other table. Unlike the plain join, it returns each matching record from the leading table only once, regardless of how many matches there are in the IN table. As with the anti-join, semi-join can also be left and right:
Coase theorem The theorem Coase_theorem > The theorem Another, more refined, normative conclusion also often discussed in law and economics is that government should create institutions that minimize transaction costs, so as to allow misallocations of resources to be corrected as cheaply as possible. (1) In the case of zero transaction costs, no matter how the rights are initially allocated, negotiations between the parties will lead to the Pareto optimal allocation of resources; (2) In the case of non-zero transaction costs, different rights allocation definitions will lead to different resource allocations; (3) Because of the existence of transaction costs, different rights definitions and allocations will bring about resource allocation with different benefits.
Communications security Key Management Infrastructure (KMI) Program Communication_security > Key Management Infrastructure (KMI) Program KMI is intended to replace the legacy Electronic Key Management System to provide a means for securely ordering, generating, producing, distributing, managing, and auditing cryptographic products (e.g., asymmetric keys, symmetric keys, manual cryptographic systems, and cryptographic applications). This system is currently being fielded by Major Commands and variants will be required for non-DoD Agencies with a COMSEC Mission.
Molybdenum Chemical properties Molybdenum > Characteristics > Chemical properties Like many heavier transition metals, molybdenum shows little inclination to form a cation in aqueous solution, although the Mo3+ cation is known under carefully controlled conditions.Gaseous molybdenum consists of the diatomic species Mo2. That molecule is a singlet, with two unpaired electrons in bonding orbitals, in addition to 5 conventional bonds. The result is a sextuple bond.
Whisker (metallurgy) Mechanism Tin_whiskers > Mechanism Metal whiskering is a crystalline metallurgical phenomenon involving the spontaneous growth of tiny, filiform hairs from a metallic surface. The effect is primarily seen on elemental metals but also occurs with alloys. The mechanism behind metal whisker growth is not well understood, but seems to be encouraged by compressive mechanical stresses including: energy gained due to electrostatic polarization of metal filaments in the electric field, residual stresses caused by electroplating, mechanically induced stresses, stresses induced by diffusion of different metals, thermally induced stresses, and strain gradients in materials.Metal whiskers differ from metallic dendrites in several respects: dendrites are fern-shaped and grow across the surface of the metal, while metal whiskers are hair-like and project normal to the surface. Dendrite growth requires moisture capable of dissolving the metal into a solution of metal ions, which are then redistributed by electromigration in the presence of an electromagnetic field. While the precise mechanism for whisker formation remains unknown, it is known that whisker formation does not require either dissolution of the metal or the presence of an electromagnetic field.
Feature control frame Summary Geometric_tolerance Geometric dimensioning and tolerancing (GD&T) is a system for defining and communicating engineering tolerances via a symbolic language on engineering drawings and computer-generated 3D models that describes a physical object's nominal geometry and the permissible variation thereof. GD&T is used to define the nominal (theoretically perfect) geometry of parts and assemblies, the allowable variation in size, form, orientation, and location of individual features, and how features may vary in relation to one another such that a component is considered satisfactory for its intended use. Dimensioning specifications define the nominal, as-modeled or as-intended geometry. One example is a basic dimension.
Oxygen Occurrence Dephlogisticated_air > Characteristics > Occurrence In the present equilibrium, production and consumption occur at the same rate.Free oxygen also occurs in solution in the world's water bodies. The increased solubility of O2 at lower temperatures (see Physical properties) has important implications for ocean life, as polar oceans support a much higher density of life due to their higher oxygen content. Water polluted with plant nutrients such as nitrates or phosphates may stimulate growth of algae by a process called eutrophication and the decay of these organisms and other biomaterials may reduce the O2 content in eutrophic water bodies. Scientists assess this aspect of water quality by measuring the water's biochemical oxygen demand, or the amount of O2 needed to restore it to a normal concentration.
Air-Cobot Navigation around the aircraft Air-Cobot > Autonomous navigation > Navigation around the aircraft The robot moves and holds this orientation by considering its wheel odometry, its inertial unit and visual odometry. Laser data are also used horizontally in two dimensions.
Pythagorean school On Western science Pythagorean_mathematics > Later influence > On Western science Mathematics regained importance and influenced philosophy as well as science. Mathematics was used by Kepler, Galileo, Descartes, Huygens and Newton to advance physical laws that reflected the inherent order of the universe.
Liver fibrosis Bleeding and blood clot risk Cirrhosis_of_the_liver > Treatment > Bleeding and blood clot risk In hospitalized patients who meet standard guidelines for clot prevention, the AGA suggests standard prevention. The AGA does not recommend in routine screening for portal vein thrombosis. If there is a portal vein thrombosis, the AGA suggests treatment by anticoagulation. In the case of cirrhosis with atrial fibrillation, the AGA recommends using anticoagulation over no anticoagulation.
Sports nutrition Anaerobic exercise Sports_nutrition > Factors influencing nutritional requirements > Anaerobic exercise Typically, high-glycemic-index carbohydrates are preferred for their ability to rapidly raise blood glucose levels. For the purpose of protein synthesis, protein or individual amino acids are ingested as well. Branched-chain amino acids are important since they are most responsible for the synthesis of protein.
Statistical significance test Courtroom trial Simple_hypothesis > Examples > Courtroom trial The hypothesis of innocence is rejected only when an error is very unlikely, because one does not want to convict an innocent defendant. Such an error is called error of the first kind (i.e., the conviction of an innocent person), and the occurrence of this error is controlled to be rare. As a consequence of this asymmetric behaviour, an error of the second kind (acquitting a person who committed the crime), is more common.
Limit at infinity History Epsilon,_delta > History He also introduced the notations lim {\textstyle \lim } and lim x → x 0 . {\textstyle \textstyle \lim _{x\to x_{0}}\displaystyle .} The modern notation of placing the arrow below the limit symbol is due to Hardy, which is introduced in his book A Course of Pure Mathematics in 1908.
Inclusive classroom Overview Inclusive_classroom > Critiques and attitudes > Overview There are conflicting attitudes regarding inclusive classrooms and teaching special needs students within mainstream classrooms as many believe that inclusivity within a classroom environment will be damaging towards the education of the neurotypical children within that educative environment. However, One study argued, "Inclusive practices allow students to become full members of a classroom community, thus allowing them to develop both academically and socially". Critiques of universal inclusion argue the practice ignores the needs of the student, and many students' needs cannot reasonably be met within general education settings. To further, it is argued that the movement for fully inclusive classrooms priorities group values and ideologies over evidence.
Kolmogorov Complexity Definition Algorithmic_complexity_theory > Definition We must first specify a description language for strings. Such a description language can be based on any computer programming language, such as Lisp, Pascal, or Java.
Radon-Nikodym Derivative Radon–Nikodym derivative Radon–Nikodym_derivative > Formal description > Radon–Nikodym derivative The function f {\displaystyle f} satisfying the above equality is uniquely defined up to a μ {\displaystyle \mu } -null set, that is, if g {\displaystyle g} is another function which satisfies the same property, then f = g {\displaystyle f=g} μ {\displaystyle \mu } -almost everywhere. The function f {\displaystyle f} is commonly written d ν d μ {\frac {d\nu }{d\mu }} and is called the Radon–Nikodym derivative. The choice of notation and the name of the function reflects the fact that the function is analogous to a derivative in calculus in the sense that it describes the rate of change of density of one measure with respect to another (the way the Jacobian determinant is used in multivariable integration).
12-Hydroxyheptadecatrienoic acid Cancer 12-Hydroxyheptadecatrienoic_acid > Activities and clinical significance > Cancer A large number of studies have associated BLT2 and, directly or by assumption, 12-HHT in the survival, growth, and/or spread of various human cancers. See 'Leukotriene B4 receptor 2 for the associations of BLT2 and/or 12-HHT with stimulating the malignant behavior of prostate cancer, urinary bladder cancer, breast cancer, thyroid gland follicular carcinoma, kidney renal cell carcinoma, bladder transitional cell carcinoma, esophageal cancer, pancreatic cancer, and colon cancer.
DiVincenzo's criteria Long relevant decoherence times DiVincenzo's_criteria > Justification > Long relevant decoherence times In solid-state NMR using nitrogen-vacancy centers, the orbital electron experiences short decoherence times, making computations problematic; the proposed solution has been to encode the qubit in the nuclear spin of the nitrogen atom, thus increasing the decoherence time. In other systems, such as the quantum dot, issues with strong environmental effects limit the T2 decoherence time. Systems that can be manipulated quickly (through strong interactions) tend to experience decoherence via these very same strong interactions, and so there is a trade-off between ability to implement control and increased decoherence.
Compiler optimization Code generator optimizations Compiler_optimization > Specific techniques > Code generator optimizations Register allocation The most frequently used variables should be kept in processor registers for fastest access. To find which variables to put in registers, an interference-graph is created. Each variable is a vertex and when two variables are used at the same time (have an intersecting liverange) they have an edge between them. This graph is colored using for example Chaitin's algorithm using the same number of colors as there are registers.
Grundzüge der physiologischen Psychologie Principles of mental causality Grundzüge_der_physiologischen_Psychologie > Methodology and strategies > Principles of mental causality There is a general tendency to order the subjective world according to opposites. Thus many individual, historical, economic and social processes exhibit highly contrasting developments. The Principle of the heterogony of purpose (ends).
Cheletropic reaction Kinetics Cheletropic_reaction > Cheletropic reactions involving SO2 > Kinetics The sulfolene is about 40 kJ/mol more stable than the isometric sulfine in CH2Cl2/SO2 solution. The authors were able to experimentally determine a rate law at 261.2 K for the reaction of 1,2-dimethylidenecyclohexane with sulfur dioxide to give the corresponding sulfolene.
Memory consolidation Reconsolidation Memory_consolidation > Reconsolidation Memory reconsolidation is the process of previously consolidated memories being recalled and actively consolidated. It is a distinct process that serves to maintain, strengthen and modify memories that are already stored in the long-term memory. Once memories undergo the process of consolidation and become part of long-term memory, they are thought of as stable.
Landiolol Mode of action Landiolol > Mode of action Activation of β2 adrenergic receptors contributes to bronchial dilation and acceleration of alveolar fluid clearance in the pulmonary airway system. Consequently, a cardio-selective β1-blocker with limited effect on β2-receptor decreases the heart rate without the pulmonary adverse effects in patients with COPD or Asthma. Pharmacological stimulation of β2 receptors increases coronary blood flow in healthy humans and in patients with mildly atherosclerotic coronary arteries.
Fractional derivative Atangana–Baleanu fractional integral Fractional_differential_equation > Fractional integrals > Atangana–Baleanu fractional integral The Atangana–Baleanu fractional integral of a continuous function is defined as:
Network Security Services Interoperability and open standards Network_Security_Services > Architecture > Interoperability and open standards PKCS #5. RSA standard that governs password-based cryptography, for example to encrypt private keys for storage. PKCS #7.
Radiation damage Embrittlement Radiation_damage > Effects on materials and devices > Effects on metals and concrete > Thermo-mechanical effects of irradiation > Embrittlement Radiation embrittlement results in a reduction of the energy to fracture, due to a reduction in strain hardening (as hardening is already occurring during irradiation). This is motivated for very similar reasons to those that cause radiation hardening; development of defect clusters, dislocations, voids, and precipitates. Variations in these parameters make the exact amount of embrittlement difficult to predict, but the generalized values for the measurement show predictable consistency.
Matrix Mechanics Transformation theory Matrix_Mechanics > Further results > Transformation theory In quantum mechanics, any unitary symmetry transformation yields a conservation law, since if the matrix U has the property that so it follows that and that the time derivative of U is zero—it is conserved. The eigenvalues of unitary matrices are pure phases, so that the value of a unitary conserved quantity is a complex number of unit magnitude, not a real number. Another way of saying this is that a unitary matrix is the exponential of i times a Hermitian matrix, so that the additive conserved real quantity, the phase, is only well-defined up to an integer multiple of 2π.
Conjugate function Description Harmonic_conjugate > Description There is an operator taking a harmonic function u on a simply connected region in R 2 {\displaystyle \mathbb {R} ^{2}} to its harmonic conjugate v (putting e.g. v(x0) = 0 on a given x0 in order to fix the indeterminacy of the conjugate up to constants). This is well known in applications as (essentially) the Hilbert transform; it is also a basic example in mathematical analysis, in connection with singular integral operators. Conjugate harmonic functions (and the transform between them) are also one of the simplest examples of a Bäcklund transform (two PDEs and a transform relating their solutions), in this case linear; more complex transforms are of interest in solitons and integrable systems. Geometrically u and v are related as having orthogonal trajectories, away from the zeros of the underlying holomorphic function; the contours on which u and v are constant cross at right angles. In this regard, u + iv would be the complex potential, where u is the potential function and v is the stream function.
Primary pulmonary hypertension Causes Pulmonary_artery_hypertension > Causes In 1998, a second conference at Évian-les-Bains addressed the causes of secondary PH. Subsequent third, fourth, and fifth (2013) World Symposia on PAH have further defined the classification of PH. The classification continues to evolve based on improved understanding of the disease mechanisms.Most recently in 2015, the WHO guidelines were updated by the European Society of Cardiology (ESC) and European Respiratory Society (ERS). These guidelines are endorsed by the International Society for Heart and Lung Transplantation, and provide the current framework for understanding and treatment of pulmonary hypertension.
Biotic homogenization Pressures leading to homogenization Biotic_homogenization > Overview > Pressures leading to homogenization Homogenization can result from either anthropomorphic or natural pressures. Many cases of species introductions are the result of either unintentional or intentional introduction of species by humans, be it for the pet trade, recreation, or agriculture. Urbanization can also have profound impacts on biota, leading to changes in assemblages. Natural selection and other evolutionary forces that lead to extinction can also potentially lead to homogenization. Sometimes, previously isolated populations can become exposed to each other naturally. Species interactions can also cause local extinctions, be the relationship predatory or pathogenic.
Steepest descent Description Gradient-based_optimization > Description Gradient descent is based on the observation that if the multi-variable function F ( x ) {\displaystyle F(\mathbf {x} )} is defined and differentiable in a neighborhood of a point a {\displaystyle \mathbf {a} } , then F ( x ) {\displaystyle F(\mathbf {x} )} decreases fastest if one goes from a {\displaystyle \mathbf {a} } in the direction of the negative gradient of F {\displaystyle F} at a , − ∇ F ( a ) {\displaystyle \mathbf {a} ,-\nabla F(\mathbf {a} )} . It follows that, if a n + 1 = a n − γ ∇ F ( a n ) {\displaystyle \mathbf {a} _{n+1}=\mathbf {a} _{n}-\gamma \nabla F(\mathbf {a} _{n})} for a small enough step size or learning rate γ ∈ R + {\displaystyle \gamma \in \mathbb {R} _{+}} , then F ( a n ) ≥ F ( a n + 1 ) {\displaystyle F(\mathbf {a_{n}} )\geq F(\mathbf {a_{n+1}} )} . In other words, the term γ ∇ F ( a ) {\displaystyle \gamma \nabla F(\mathbf {a} )} is subtracted from a {\displaystyle \mathbf {a} } because we want to move against the gradient, toward the local minimum. With this observation in mind, one starts with a guess x 0 {\displaystyle \mathbf {x} _{0}} for a local minimum of F {\displaystyle F} , and considers the sequence x 0 , x 1 , x 2 , … {\displaystyle \mathbf {x} _{0},\mathbf {x} _{1},\mathbf {x} _{2},\ldots } such that x n + 1 = x n − γ n ∇ F ( x n ) , n ≥ 0.
Swept wings Sweep theory Wing_sweep > Aerodynamic design > Sweep theory The lift produced by a wing is directly related to the speed of the air over the wing. Since the airflow speed experienced by a swept wing is lower than what the actual aircraft speed is, this becomes a problem during slow-flight phases, such as takeoff and landing. There have been various ways of addressing the problem, including the variable-incidence wing design on the Vought F-8 Crusader, and swing wings on aircraft such as the F-14, F-111, and the Panavia Tornado.
Cross-validation (statistics) Summary Cross-validation_(statistics) Cross-validation, sometimes called rotation estimation or out-of-sample testing, is any of various similar model validation techniques for assessing how the results of a statistical analysis will generalize to an independent data set. Cross-validation is a resampling method that uses different portions of the data to test and train a model on different iterations. It is mainly used in settings where the goal is prediction, and one wants to estimate how accurately a predictive model will perform in practice. In a prediction problem, a model is usually given a dataset of known data on which training is run (training dataset), and a dataset of unknown data (or first seen data) against which the model is tested (called the validation dataset or testing set).
Henstock integral Summary Henstock_integral Denjoy was interested in a definition that would allow one to integrate functions like f ( x ) = 1 x sin ⁡ ( 1 x 3 ) . {\displaystyle f(x)={\frac {1}{x}}\sin \left({\frac {1}{x^{3}}}\right).} This function has a singularity at 0, and is not Lebesgue integrable.
Robotic manipulation Dynamics and kinematics Robotic_kitchen > Research > Dynamics and kinematics Once all relevant positions, velocities, and accelerations have been calculated using kinematics, methods from the field of dynamics are used to study the effect of forces upon these movements. Direct dynamics refers to the calculation of accelerations in the robot once the applied forces are known. Direct dynamics is used in computer simulations of the robot.
GNU Units The GNU implementation GNU_Units > History > The GNU implementation Conversions can be made to sums of units, termed unit lists (e.g., from degrees to degrees, minutes, and seconds). Units that measure reciprocal dimensions can be converted (e.g., S to megohm).
Finite element updating The process Finite_element_updating > The process The process is conducted by first choosing the domain in which data is presented. The domains used include time domain, frequency domain, modal domain, and time-frequency domain. The second step is to determine which parts of the initial models are thought to have been modeled incorrectly. The third task is to formulate a function which has the parameters that are expected to be design variables, and which represents the distance between the measured data and the finite element model predicted data.
HIV Genetic variability HIV > Virology > Genetic variability This hybrid virion then infects a new cell where it undergoes replication. As this happens, the reverse transcriptase, by jumping back and forth between the two different RNA templates, will generate a newly synthesized retroviral DNA sequence that is a recombinant between the two parental genomes. This recombination is most obvious when it occurs between subtypes.The closely related simian immunodeficiency virus (SIV) has evolved into many strains, classified by the natural host species.
Bott–Chern cohomology Bott–Chern cohomology Ddbar_lemma > Bott–Chern cohomology The Bott–Chern cohomology is a cohomology theory for compact complex manifolds which depends on the operators ∂ {\displaystyle \partial } and ∂ ¯ {\displaystyle {\bar {\partial }}} , and measures the extent to which the ∂ ∂ ¯ {\displaystyle \partial {\bar {\partial }}} -lemma fails to hold. In particular when a compact complex manifold is a Kähler manifold, the Bott–Chern cohomology is isomorphic to the Dolbeault cohomology, but in general it contains more information. The Bott–Chern cohomology groups of a compact complex manifold are defined by Since a differential form which is both ∂ {\displaystyle \partial } and ∂ ¯ {\displaystyle {\bar {\partial }}} -closed is d {\displaystyle d} -closed, there is a natural map H B C p , q ( X ) → H d R p + q ( X , C ) {\displaystyle H_{BC}^{p,q}(X)\to H_{dR}^{p+q}(X,\mathbb {C} )} from Bott–Chern cohomology groups to de Rham cohomology groups. There are also maps to the ∂ {\displaystyle \partial } and ∂ ¯ {\displaystyle {\bar {\partial }}} Dolbeault cohomology groups H B C p , q ( X ) → H ∂ p , q ( X ) , H ∂ ¯ p , q ( X ) {\displaystyle H_{BC}^{p,q}(X)\to H_{\partial }^{p,q}(X),H_{\bar {\partial }}^{p,q}(X)} .
Gravimetric analysis Volatilization methods Gravimetric_analysis > Volatilization methods Volatilization methods can be either direct or indirect. Water eliminated in a quantitative manner from many inorganic substances by ignition is an example of a direct determination. It is collected on a solid desiccant and its mass determined by the gain in mass of the desiccant. Another direct volatilization method involves carbonates which generally decompose to release carbon dioxide when acids are used.
Force vector Third law Force_vector > Newtonian mechanics > Third law If an external force acts on the system, it will make the center of mass accelerate in proportion to the magnitude of the external force divided by the mass of the system. : 19-1 Combining Newton's Second and Third Laws, it is possible to show that the linear momentum of a system is conserved in any closed system. In a system of two particles, if p → 1 {\displaystyle {\vec {p}}_{1}} is the momentum of object 1 and p → 2 {\displaystyle {\vec {p}}_{2}} the momentum of object 2, then Using similar arguments, this can be generalized to a system with an arbitrary number of particles. In general, as long as all forces are due to the interaction of objects with mass, it is possible to define a system such that net momentum is never lost nor gained. : ch.12
Inflammatory demyelinating diseases of the CNS Atypical lesion location variants Rapidly_progressive_multiple_sclerosis > Variants still idiopathic > Atypical lesion location variants Also the location of the lesions can be used to classify variants:
Light speed Electromagnetic constants The_speed_of_light_in_vacuum > Measurement > Electromagnetic constants An option for deriving c that does not directly depend on a measurement of the propagation of electromagnetic waves is to use the relation between c and the vacuum permittivity ε0 and vacuum permeability μ0 established by Maxwell's theory: c2 = 1/(ε0μ0). The vacuum permittivity may be determined by measuring the capacitance and dimensions of a capacitor, whereas the value of the vacuum permeability was historically fixed at exactly 4π×10−7 H⋅m−1 through the definition of the ampere. Rosa and Dorsey used this method in 1907 to find a value of 299710±22 km/s. Their method depended upon having a standard unit of electrical resistance, the "international ohm", and so its accuracy was limited by how this standard was defined.
Primecoin History Primecoin > History Primecoin was launched in 2013 by Sunny King, who also founded Peercoin.Unlike other cryptocurrencies, which are mined using algorithms that solved mathematical problems with no extrinsic value, mining Primecoin involves producing chains of prime numbers (Cunningham and bi-twin chains). These are useful to scientists and mathematicians and meet the requirements for a proof of work system of being hard to compute but easy to verify and having an adjustable difficulty.Shortly after its launch, some trade journals reported that the rush of over 18,000 new users seeking to mine Primecoin overwhelmed providers of dedicated servers.Primecoin has a block time of one minute, changes difficulty every block, and has a block reward that is a function of the difficulty.
Moonlighting Proteins Clinical significance Moonlighting_Proteins > Clinical significance Excessive apoptosis is involved in many neurodegenerative diseases, such as Huntington's, Alzheimer's, and Parkinson's as well as in brain ischemia. In one case, GAPDH was found in the degenerated neurons of individuals who had Alzheimer's disease.Although there is insufficient evidence for definite conclusions, there are well documented examples of moonlighting proteins that play a role in disease. One such disease is tuberculosis.
Hereditary diffuse leukoencephalopathy with spheroids Causes Hereditary_diffuse_leukoencephalopathy_with_spheroids > Causes The cause of HDLS in most families is mutation in the colony stimulating factor 1 receptor (CSF1R), a growth factor for microglia and monocyte/macrophages, suggesting that microglial dysfunction may be primary in HDLS.The mutations are concentrated in tyrosine kinase domain (TKD) of the protein. Mutations were mainly found in exons 12-22 of the intracellular TKD, including 10 missense mutations that have a single nucleotide deletion and a single codon deletion that consists of a triplet of nucleotides that have been removed causing a whole amino acid to not be coded. Additionally, three splice site mutations were identified that caused an in-frame deletion of an exon, an expressed nucleotide sequence, leading to the removal of more than 40 amino acids in the TKD.This determination has based upon genetic studies of 14 HDLS families confirming mutations in this gene.
Brain inflammation Limbic encephalitis Brain_inflammation > Cause > Limbic encephalitis Limbic encephalitis refers to inflammatory disease confined to the limbic system of the brain. The clinical presentation often includes disorientation, disinhibition, memory loss, seizures, and behavioral anomalies. MRI imaging reveals T2 hyperintensity in the structures of the medial temporal lobes, and in some cases, other limbic structures. Some cases of limbic encephalitis are of autoimmune origin.
Conjugated system Chemical bonding in conjugated systems Conjugated_system > Chemical bonding in conjugated systems The interaction that results in σ bonding takes the form of head-to-head overlap of the larger lobe of each hybrid orbital (or the single spherical lobe of a hydrogen 1s orbital). Each atomic orbital contributes one electron when the orbitals overlap pairwise to form two-electron σ bonds, or two electrons when the orbital constitutes a lone pair. These localized orbitals (bonding and non-bonding) are all located in the plane of the molecule, with σ bonds mainly localized between nuclei along the internuclear axis.
Plant immunity Immune system Plant_immunity > Immune system The plant immune system carries two interconnected tiers of receptors, one most frequently sensing molecules outside the cell and the other most frequently sensing molecules inside the cell. Both systems sense the intruder and respond by activating antimicrobial defenses in the infected cell and neighboring cells. In some cases, defense-activating signals spread to the rest of the plant or even to neighboring plants. The two systems detect different types of pathogen molecules and classes of plant receptor proteins.The first tier is primarily governed by pattern recognition receptors that are activated by recognition of evolutionarily conserved pathogen or microbial–associated molecular patterns (PAMPs or MAMPs).
Coordination (linguistics) Mismatch in syntactic category Coordination_(linguistics) > Coordination in different languages > Unique behaviour in English > Mismatch in syntactic category The examples above illustrate that the conjuncts are often alike in syntactic category. There are, though, many instances of coordination where the coordinated strings are NOT alike, e.g. Sarah is and . - NP + AP Is Jim and ? - A + NP Bill is and .
Molar entropy The fundamental thermodynamic relation Specific_entropy > Applications > The fundamental thermodynamic relation The entropy of a system depends on its internal energy and its external parameters, such as its volume. In the thermodynamic limit, this fact leads to an equation relating the change in the internal energy U {\displaystyle U} to changes in the entropy and the external parameters. This relation is known as the fundamental thermodynamic relation.
Thermal contact Summary Thermal_contact In heat transfer and thermodynamics, a thermodynamic system is said to be in thermal contact with another system if it can exchange energy through the process of heat. Perfect thermal isolation is an idealization as real systems are always in thermal contact with their environment to some extent. When two solid bodies are in contact, a resistance to heat transfer exists between the bodies. The study of heat conduction between such bodies is called thermal contact conductance (or thermal contact resistance).
Speed Graphic Description Speed_Graphic > Description Despite the common appellation of Speed Graphic, various Graphic models were produced between 1912 and 1973. The authentic Speed Graphic has a focal plane shutter that the Crown Graphic and Century Graphic models lack. The eponymous name "speed" came from the maximum speed of 1/1000 sec. that could be achieved with the focal plane shutter. The Speed Graphic was available in 2¼ x 3¼ inch, 3¼ x 4¼ inch, 5 x 7 inch and the most common format 4 x 5 inch.
False negatives Ambiguity in the definition of false positive rate True_negative > Related terms > Ambiguity in the definition of false positive rate Despite the fact that the likelihood ratio in favor of the alternative hypothesis over the null is close to 100, if the hypothesis was implausible, with a prior probability of a real effect being 0.1, even the observation of p = 0.001 would have a false positive rate of 8 percent. It wouldn't even reach the 5 percent level. As a consequence, it has been recommended that every p-value should be accompanied by the prior probability of there being a real effect that it would be necessary to assume in order to achieve a false positive risk of 5%. For example, if we observe p = 0.05 in a single experiment, we would have to be 87% certain that there as a real effect before the experiment was done to achieve a false positive risk of 5%.
Salinity control Drainage systems Salinity_control > Drainage systems In many cases a seasonal average water table depth of 0.6 to 0.8 m is deep enough. This means that the water table may occasionally be less than 0.6 m (say 0.2 m just after an irrigation or a rain storm). This automatically implies that, in other occasions, the water table will be deeper than 0.8 m (say 1.2 m).
Glossary of aerospace engineering K Glossary_of_aerospace_engineering > K Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes. The same amount of work is done by the body when decelerating from its current speed to a state of rest. In classical mechanics, the kinetic energy of a non-rotating object of mass m traveling at a speed v is 1 2 m v 2 {\textstyle {\frac {1}{2}}mv^{2}} .
Pathological (mathematics) Well-behaved Pathological_(mathematics) > Well-behaved In probability, events contained in the probability space's corresponding sigma-algebra are well-behaved, as are measurable functions.Unusually, the term could also be applied in a comparative sense: In calculus: Analytic functions are better-behaved than general smooth functions. Smooth functions are better-behaved than general differentiable functions. Continuous differentiable functions are better-behaved than general continuous functions.
Chinese room System reply Chinese_room > Replies > Systems and virtual mind replies: finding the mind > System reply If we assume a "mind" is a form of information processing, then the theory of computation can account for two computations occurring at once, namely (1) the computation for universal programmability (which is the function instantiated by the person and note-taking materials independently from any particular program contents) and (2) the computation of the Turing machine that is described by the program (which is instantiated by everything including the specific program). The theory of computation thus formally explains the open possibility that the second computation in the Chinese Room could entail a human-equivalent semantic understanding of the Chinese inputs. The focus belongs on the program's Turing machine rather than on the person's.
Cellular neural network Semiconductors Cellular_neural_network > Physical implementations > Semiconductors Although the accuracy of analog CNN processors does not compare to their digital counterparts, for many applications, noise and process variances are small enough not to perceptually affect the image quality. The first algorithmically programmable, analog CNN processor was created in 1993. It was named the CNN Universal Processor because its internal controller allowed multiple templates to be performed on the same data set, thus simulating multiple layers and allowing for universal computation.
Bernoulli Equation Unsteady potential flow Bernoulli’s_principle > Incompressible flow equation > Unsteady potential flow As a result, the Bernoulli equation at some moment t applies in the whole fluid domain. This is also true for the special case of a steady irrotational flow, in which case f and ∂φ/∂t are constants so equation (A) can be applied in every point of the fluid domain. : 383 Further f(t) can be made equal to zero by incorporating it into the velocity potential using the transformation: resulting in: Note that the relation of the potential to the flow velocity is unaffected by this transformation: ∇Φ = ∇φ. The Bernoulli equation for unsteady potential flow also appears to play a central role in Luke's variational principle, a variational description of free-surface flows using the Lagrangian mechanics.
Covariance and contravariance (computer science) Summary Covariance_and_contravariance_(computer_science) A programming language designer will consider variance when devising typing rules for language features such as arrays, inheritance, and generic datatypes. By making type constructors covariant or contravariant instead of invariant, more programs will be accepted as well-typed. On the other hand, programmers often find contravariance unintuitive, and accurately tracking variance to avoid runtime type errors can lead to complex typing rules. In order to keep the type system simple and allow useful programs, a language may treat a type constructor as invariant even if it would be safe to consider it variant, or treat it as covariant even though that could violate type safety.
Tsai-Hill failure criterion Summary Tsai-Hill_failure_criterion The Tsai–Hill failure criterion is one of the phenomenological material failure theories, which is widely used for anisotropic composite materials which have different strengths in tension and compression. The Tsai-Hill criterion predicts failure when the failure index in a laminate reaches 1.
Software development security Basic practices Software_development_security > Basic practices The following lists some of the recommended web security practices that are more specific for software developers. Sanitize inputs at the client side and server side Encode request/response Use HTTPS for domain entries Use only current encryption and hashing algorithms Do not allow for directory listing Do not store sensitive data inside cookies Check the randomness of the session Set secure and HttpOnly flags in cookies Use TLS not SSL Set strong password policy Do not store sensitive information in a form's hidden fields Verify file upload functionality Set secure response headers Make sure third party libraries are secured Hide web server information
Open problem in mathematics Prime numbers Open_problem_in_mathematics > Unsolved problems > Number theory > Prime numbers Are there infinitely many safe and Sophie Germain primes? Are there infinitely many Wagstaff primes? Are there infinitely many Wieferich primes?
Ludvig Sylow Sylow's theorems Ludvig_Sylow > Career as a mathematician > Sylow's theorems Since few contemporary mathematicians were as deeply familiar with Abel's work as Sylow was, Professor Carl Anton Bjerknes advised him to study Évariste Galois's works about group theory, in which Abel had also contributed a lot. However, it was only when Sylow began to lecture about Abel's and Galois's work on algebraic equations in 1862, that he began to further develop their innovative works, especially those related to group theory, and in fact, by the end of that year, Sylow had already proved foundational results in group theory, which are now known as Sylow theorems and p-groups, known as Sylow subgroups, which are now basic terms in group theory. He was thus one of the first mathematicians to penetrate Galois' group theory. However, it was not until 1872, 10 years later, that Sylow published his most important discoveries in group theory in Alfred Clebsch's journal (Math.
Dependent variables Other variables Response_variable > Other variables A variable may be thought to alter the dependent or independent variables, but may not actually be the focus of the experiment. So that the variable will be kept constant or monitored to try to minimize its effect on the experiment. Such variables may be designated as either a "controlled variable", "control variable", or "fixed variable". Extraneous variables, if included in a regression analysis as independent variables, may aid a researcher with accurate response parameter estimation, prediction, and goodness of fit, but are not of substantive interest to the hypothesis under examination.
Velocity ratio Automotive applications Speed_ratio > Automotive applications Automobile drivetrains generally have two or more major areas where gearing is used. Gearing is employed in the transmission, which contains a number of different sets of gears that can be changed to allow a wide range of vehicle speeds, and also in the differential, which contains the final drive to provide further speed reduction at the wheels. In addition, the differential contains further gearing that splits torque equally between the two wheels while permitting them to have different speeds when travelling in a curved path. The transmission and final drive might be separate and connected by a driveshaft, or they might be combined into one unit called a transaxle. The gear ratios in transmission and final drive are important because different gear ratios will change the characteristics of a vehicle's performance.
Magnetic sense In birds Magnetoreception > Taxonomic range > In vertebrates > In birds This was based on two findings: First, magnetite-containing cells were reported in specific locations in the upper beak. However, the cells proved to be immune system macrophages, not neurons able to detect magnetic fields.
Fourier shift theorem Other notations Fourier_transformation > Other notations Since the result of applying the Fourier transform is again a function, we can be interested in the value of this function evaluated at the value ξ for its variable, and this is denoted either as F f(ξ) or as (F f)(ξ). Notice that in the former case, it is implicitly understood that F is applied first to f and then the resulting function is evaluated at ξ, not the other way around. In mathematics and various applied sciences, it is often necessary to distinguish between a function f and the value of f when its variable equals x, denoted f(x).
Xenobiology Genetic code engineering Xenobiology > Scientific approach > Genetic code engineering In that situation, the canonical amino acid residues in native proteins are substituted with the ncAAs. Even the insertion of multiple different ncAAs into the same protein is possible.
Moment distribution method Distribution factors Moment_distribution_method > Implementation > Distribution factors When a joint is being released and begins to rotate under the unbalanced moment, resisting forces develop at each member framed together at the joint. Although the total resistance is equal to the unbalanced moment, the magnitudes of resisting forces developed at each member differ by the members' bending stiffness. Distribution factors can be defined as the proportions of the unbalanced moments carried by each of the members. In mathematical terms, the distribution factor of member k {\displaystyle k} framed at joint j {\displaystyle j} is given as: D j k = E k I k L k ∑ i = 1 i = n E i I i L i {\displaystyle D_{jk}={\frac {\frac {E_{k}I_{k}}{L_{k}}}{\sum _{i=1}^{i=n}{\frac {E_{i}I_{i}}{L_{i}}}}}} where n is the number of members framed at the joint.
Vertical triple expansion Compound systems Triple-expansion_steam_engine > Compound systems Ideally, the steam would expand adiabatically, and the temperature would drop corresponding to the volume increase. However, in practice the material of the surrounding cylinder acts as a heat reservoir, cooling the steam in the earlier part of the expansion and heating it in the later part. These irreversible heat flows decrease the efficiency of the process, so that beyond a certain point, further increasing the expansion ratio would actually decrease efficiency, in addition to decreasing the mean effective pressure and thus the power of the engine.
Keyed-hash message authentication code Design principles Hash-based_message_authentication_code > Design principles The design of the HMAC specification was motivated by the existence of attacks on more trivial mechanisms for combining a key with a hash function. For example, one might assume the same security that HMAC provides could be achieved with MAC = H(key ∥ message). However, this method suffers from a serious flaw: with most hash functions, it is easy to append data to the message without knowing the key and obtain another valid MAC ("length-extension attack").
Sympathoadrenal system Exercise and Metabolism Sympathoadrenal_system > Exercise and Metabolism During exercise, the body undergoes a stress response in which more oxygen and energy is needed for physical activity. The stress induced during exercise results in an increase in the hormones, epinephrine and norepinephrine, which are known for the body's "fight or flight" response. As a result, the body's heart rate increases allowing for more blood to pump through the body system and carry oxygen needed for breathing to enhance cardiorespiratory function. In exercise trained individuals, levels of epinephrine and norepinephrine are lower compared to those who do not actively train as much.
Factorial number system Fractional values Factorial_number_system > Fractional values {\displaystyle 11/12=0.0\ 1\ 2\ 2_{!}} 1 / 15 = 0.0 0 0 1 3 ! {\displaystyle 1/15=0.0\ 0\ 0\ 1\ 3_{!}}
Technical drawing tool Drafting board Technical_drawing_tool > Drawing tools > Drafting board The drawing board is an essential tool. Paper will be attached and kept straight and still, so that the drawing can be done with accuracy. Generally, different kind of assistance rulers are used in drawing. The drawing board is usually mounted to a floor pedestal in which the board turns to a different position, and also its height can be adjustable.
Current solar income Summary Current_solar_income The current solar income of the Earth, or any ecoregion of the earth, is the amount of solar energy that falls on it as sunlight. This is thought important in some branches of green economics, as the ultimate measure of renewable energy. Buckminster Fuller first described the concept in his 1970 paper Cosmic Costing, contrasting the photosynthesis on which natural capital and sustainable infrastructural capital depend, with the chemosynthesis of extracting and using fossil fuels. Paul Hawken is a more recent advocate of the concept, and views it as central to his notion of a restorative economy. It remains a popular notion among those who believe that toxic waste and maintenance problems of direct solar energy devices can ultimately be overcome, or that yields of passive or biological means of gathering and using this energy as biofuels can be made to approximate those of fossil fuels.
Mobile membranes Enhanced Mobile Membranes Mobile_membranes > Computability Power of Mobile Membranes > Enhanced Mobile Membranes {\mathcal {N}}} , u ∈ V + , v , v ′ , w , w ′ ∈ V ∗ {\displaystyle u\!\in \!V^{+},v,v'\!,w,w'\!\in \!V^{}} ; (enhanced endocytosis) h ‖ N ] m → h ‖ m {\displaystyle _{h}\;\\|\;N]_{m}\!\!\rightarrow \!\!_{h}\;\\|\;_{m}} for h , m ∈ N , u ∈ V + , v , v ′ , w , w ′ ∈ V ∗ {\displaystyle h,m\!\in \! {\mathcal {N}},u\in V^{+},v,v',w,w'\in V^{}} ;(enhanced exocytosis) \noindent where M {\displaystyle M} is a multiset and N {\displaystyle N} is an arbitrary membrane configuration. The computational power of the systems of enhanced mobile membranes using these four operations was studied in where it is proved that twelve membranes can provide the computational universality, while in the result is improved by reducing the number of membranes to nine.
Online transaction processing Overview Online_transaction_processing > Overview Online transaction processing (OLTP) involves gathering input information, processing the data and updating existing data to reflect the collected and processed information. As of today, most organizations use a database management system to support OLTP. OLTP is carried in a client-server system.
Cat cracker Mechanism and products of catalytic cracking Cat_cracker > Mechanism and products of catalytic cracking Those olefinic gases are valuable for use as petrochemical feedstocks. The propylene, butylene and isobutylene are also valuable feedstocks for certain petroleum refining processes that convert them into high-octane gasoline blending components.
Kepler-38b Planetary system Kepler-38b > Planetary system In 2012, a circumbinary Neptune-sized planet was found transiting the brighter star. Follow-up radial velocity measurements did not give sufficient information to constrain the mass of the planet. The planet was confirmed via transit duration variation method. It is likely that additional planets in the habitable zone exist, including rocky terrestrial planets, according to simulations of the formation of the Kepler-38 system; furthermore, the orbits of any such planets are probably stable.

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