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https://en.wikipedia.org/wiki/Archimedean%20ordered%20vector%20space | In mathematics, specifically in order theory, a binary relation on a vector space over the real or complex numbers is called Archimedean if for all whenever there exists some such that for all positive integers then necessarily
An Archimedean (pre)ordered vector space is a (pre)ordered vector space whose order is Archimedean.
A preordered vector space is called almost Archimedean if for all whenever there exists a such that for all positive integers then
Characterizations
A preordered vector space with an order unit is Archimedean preordered if and only if for all non-negative integers implies
Properties
Let be an ordered vector space over the reals that is finite-dimensional. Then the order of is Archimedean if and only if the positive cone of is closed for the unique topology under which is a Hausdorff TVS.
Order unit norm
Suppose is an ordered vector space over the reals with an order unit whose order is Archimedean and let
Then the Minkowski functional of (defined by ) is a norm called the order unit norm.
It satisfies and the closed unit ball determined by is equal to (that is,
Examples
The space of bounded real-valued maps on a set with the pointwise order is Archimedean ordered with an order unit (that is, the function that is identically on ).
The order unit norm on is identical to the usual sup norm:
Examples
Every order complete vector lattice is Archimedean ordered.
A finite-dimensional vector lattice of dimension is Archimedean ordered if and only if it is isomorphic to with its canonical order.
However, a totally ordered vector order of dimension can not be Archimedean ordered.
There exist ordered vector spaces that are almost Archimedean but not Archimedean.
The Euclidean space over the reals with the lexicographic order is Archimedean ordered since for every but
See also
References
Bibliography
Functional analysis
Order theory |
https://en.wikipedia.org/wiki/Solid%20set | In mathematics, specifically in order theory and functional analysis, a subset of a vector lattice is said to be solid and is called an ideal if for all and if then
An ordered vector space whose order is Archimedean is said to be Archimedean ordered.
If then the ideal generated by is the smallest ideal in containing
An ideal generated by a singleton set is called a principal ideal in
Examples
The intersection of an arbitrary collection of ideals in is again an ideal and furthermore, is clearly an ideal of itself;
thus every subset of is contained in a unique smallest ideal.
In a locally convex vector lattice the polar of every solid neighborhood of the origin is a solid subset of the continuous dual space ;
moreover, the family of all solid equicontinuous subsets of is a fundamental family of equicontinuous sets, the polars (in bidual ) form a neighborhood base of the origin for the natural topology on (that is, the topology of uniform convergence on equicontinuous subset of ).
Properties
A solid subspace of a vector lattice is necessarily a sublattice of
If is a solid subspace of a vector lattice then the quotient is a vector lattice (under the canonical order).
See also
References
Functional analysis
Order theory |
https://en.wikipedia.org/wiki/Order%20topology%20%28functional%20analysis%29 | In mathematics, specifically in order theory and functional analysis, the order topology of an ordered vector space is the finest locally convex topological vector space (TVS) topology on for which every order interval is bounded, where an order interval in is a set of the form where and belong to
The order topology is an important topology that is used frequently in the theory of ordered topological vector spaces because the topology stems directly from the algebraic and order theoretic properties of rather than from some topology that starts out having.
This allows for establishing intimate connections between this topology and the algebraic and order theoretic properties of
For many ordered topological vector spaces that occur in analysis, their topologies are identical to the order topology.
Definitions
The family of all locally convex topologies on for which every order interval is bounded is non-empty (since it contains the coarsest possible topology on ) and the order topology is the upper bound of this family.
A subset of is a neighborhood of the origin in the order topology if and only if it is convex and absorbs every order interval in
A neighborhood of the origin in the order topology is necessarily an absorbing set because for all
For every let and endow with its order topology (which makes it into a normable space).
The set of all 's is directed under inclusion and if then the natural inclusion of into is continuous.
If is a regularly ordered vector space over the reals and if is any subset of the positive cone of that is cofinal in (e.g. could be ), then with its order topology is the inductive limit of (where the bonding maps are the natural inclusions).
The lattice structure can compensate in part for any lack of an order unit:
In particular, if is an ordered Fréchet lattice over the real numbers then is the ordered topology on if and only if the positive cone of is a normal cone in
If is a regular |
https://en.wikipedia.org/wiki/Europium%20hydride | Europium hydride is the most common hydride of europium with a chemical formula EuH2. In this compound, europium atom is in the +2 oxidation state and the hydrogen atoms are -1. It is a ferromagnetic semiconductor.
Production
Europium hydride can be produced by directly reacting europium and hydrogen gas:
Eu + H2 → EuH2
Uses
EuH2 can be used as a source of Eu2+ to create metal-organic frameworks that have the Eu2+ ion.
References
Europium(II) compounds
Metal hydrides
Ferromagnetic materials |
https://en.wikipedia.org/wiki/Base%2050 | A Base 50 engine is a generic term for engines that are reverse-engineered from the Honda air-cooled four-stroke single cylinder engine. Honda first offered these engines in 1958, on their Honda Super Cub 50. Honda has offered variations of this engine continuously, in sizes up to , since its introduction. The Honda Super Cub has been produced in excess of 100,000,000 units, the most successful motorized vehicle in history. With multiple manufactures utilizing clones of the Honda 50 engine for current mopeds, scooters, small motorcycles and power sport machines, it is the most produced engine in history.
The engines are usually identical in form, fit and function to Honda 50cc engines and the parts are usually interchangeable with genuine Honda parts.
The term Base 50 has originated from the importation of modern styled, small Pit Bikes that use the Honda CRF50 as a base for design. Base 50's have also been known as Chondas, a slang term due to influx of Honda clone engines being primarily from China. The name, a portmanteau of "Chinese" or "clone", and "Honda", is seldom used in direct sales marketing.
Intellectual property infringement
Honda has a presence in China and shares manufacturing facilities with local industry, as required by Chinese local content trade law. Despite this, Honda has never pursued infringements regarding patents or intellectual property specifically regarding the Honda 50 or Base 50 engines, as the patents for said engines exceed 30 years. Honda has pursued legal action against Lifan regarding other business practices, including Lifans use of Hongda for marketing motorcycles. Honda also won a patent lawsuit in 2007 regarding a separate infringement for the sale of the Lifan LF100T motorcycle
References
Engines |
https://en.wikipedia.org/wiki/Delphibacteria | Delphibacteria is a candidate bacterial phylum in the FCB group. The phylum was first proposed after analysis of two genomes from the mouths of two bottlenose dolphins. "Dephibacteria" was proposed in recognition of the first genomic representatives having been recovered from the dolphin mouth. Members of the Delphibacteria phylum have been retroactively detected in a variety of environments.
Description
Delphibacteria is a bacterial phylum with candidate status, meaning it has no cultured representatives as of yet. It is part of the FCB group.
History
The phylum was first proposed following the recovery and analysis of two genomes, each from the mouth of a different bottlenose dolphin. These dolphins were part of the US Navy's Marine Mammal Program, although Delphibacteria 16S rRNA genes have also been detected in the mouths of wild dolphins living off the coast of Florida, U.S. The first characterized member of the Delphibacteria phylum was inferred to be a heterotrophic organism with the genomic potential for oxygen and most likely nitrate reduction. It was hypothesized that the ability to perform denitrification may have an impact on dolphin physiology and health, given that in humans denitrification by oral bacteria can affect oral and gastric blood flow, signalling in bacteria-bacteria and bacteria-host interactions, and mucus thickness in the stomach.
The name "Delphibacteria" was proposed in recognition of the first genomic representatives having been recovered from the dolphin mouth (Family Delphinidae) and due to its ubiquity in dolphin mouths. Members of the Delphibacteria phylum have been detected (retroactively) in a variety of environments, including bottom water from the Northern Bering Sea (EU734960.1), marine sediment from the Logatchec hydrothermal vent (FN554086.1), and deep sea sediment from the Okinawa Trough (KX097792.1).
References
Bacteria
Dolphins
Genomics |
https://en.wikipedia.org/wiki/Genetic%20interaction%20network | Genetic interaction networks represent the functional interactions between pairs of genes in an organism and are useful for understanding the relation between genotype and phenotype. The majority of genes do not code for particular phenotypes. Instead, phenotypes often result from the interaction between several genes. In humans, "Each individual carries ~4 million genetic variants and polymorphisms, the overwhelming majority of which cannot be pinpointed as the single cause for a given phenotype. Instead, the effects of genetic variants may combine with one another both additively and synergistically, and each variant's contribution to a quantitative trait or disease risk could depend on the genotypes of dozens of other variants. Interactions between genetic variants, along with the environmental conditions, are likely to play a major role in determining the phenotype that arises from a given genotype." Genetic interaction networks help to understand genetic interactions by identifying such interactions between pairs of genes.
Because genetic interactions provide insight into how genotype connects to phenotype in an organism, improved knowledge of genetic interactions in humans could provide crucial insight into complex diseases. Unfortunately, due to the impossibility of isolating subjects with single genetic variants, it is not possible to directly map the genetic interaction networks in humans. Researchers hope that learning about the characteristics of genetic interaction networks in suitable organisms will provide tools for constructing the genetic interaction network of humans.
Overview
A genetic interaction occurs when the interactions between two or more genes results in a phenotype that differs from the phenotype expected if the genes were independent of each other. In the context of genetic interaction networks, a genetic interaction is defined as "the difference between an experimentally measured double-mutant phenotype and an expected double-mutant |
https://en.wikipedia.org/wiki/Magnetic%202D%20materials | Magnetic 2D materials or magnetic van der Waals materials are two-dimensional materials that display ordered magnetic properties such as antiferromagnetism or ferromagnetism. After the discovery of graphene in 2004, the family of 2D materials has grown rapidly. There have since been reports of several related materials, all except for magnetic materials. But since 2016 there have been numerous reports of 2D magnetic materials that can be exfoliated with ease just like graphene.
The first few-layered van der Waals magnetism was reported in 2017 (Cr2Ge2Te6, and CrI3). One reason for this seemingly late discovery is that thermal fluctuations tend to destroy magnetic order for 2D magnets easier compared to 3D bulk. It is also generally accepted in the community that low dimensional materials have different magnetic properties compared to bulk. This academic interest that transition from 3D to 2D magnetism can be measured has been the driving force behind much of the recent works on van der Waals magnets. Much anticipated transition of such has been since observed in both antiferromagnets and ferromagnets: FePS3, Cr2Ge2Te6, CrI3, NiPS3, MnPS3, Fe3GeTe2
Although the field has been only around since 2016, it has become one of the most active fields in condensed matter physics and materials science and engineering. There have been several review articles written up to highlight its future and promise.
Overview
Magnetic van der Waals materials is a new addition to the growing list of 2d materials. The special feature of these new materials is that they exhibit a magnetic ground state, either antiferromagnetic or ferromagnetic, when they are thinned down to very few sheets or even one layer of materials. Another, a probably more important feature of these materials is that they can be easily produced in few layers or monolayer form using simple means such as scotch tape, which is rather uncommon among other magnetic materials like oxide magnets.
Interest in these material |
https://en.wikipedia.org/wiki/Simply%20Local | Simply Local is a decentralized community social networking and neighborhood broadcasting service developed by Simply Local, based in New Delhi. The app is used as a tool by residents to bridge the information gap and know what is happening in the locality.
Simply Local creates private geo-fenced networks for people living in an area and provides social and community related services within that network. The user doesn’t post to a single person but broadcasts to a chosen community. One of its primary purposes is also to connect citizens to their elected representatives. Each community is independent of the other and information shared remains telescoped to that particular community. The app has been designed to maintain privacy and security of users and provides decentralized social networking in the sense that it forms an owner-independent, micro community, which is not connected with the world outside.
Simply Local is available on Android Play and iOS App Store. It is available in two languages - English and Hindi. Simply Local’s founder and CEO is Nikhil Bapna.
History
2020 May: Included as a Top 5 Useful App by Zee News.
2020: Used to connect candidates with local residents during the Delhi assembly elections.
2019: Renamed from Gadfly to its current name.
2018: Used for Karnataka State Elections to get detailed information on candidates.
2017: Launched under the name Gadfly as a tool to connect citizens with their elected representatives.
References
Social media
Social networking services
Location-based software
Mobile social software
Proprietary cross-platform software
Cross-platform software
Social networks for social change
Geosocial networking
Social networking mobile apps |
https://en.wikipedia.org/wiki/Braefoot%20Battery | The Braefoot Battery was a World War I coastal defence gun battery defending the Firth of Forth. The battery was constructed in 1915 at Braefoot Point, then part of the Earl of Moray's Donibristle Estate. The site is situated between the new town of Dalgety Bay and Aberdour in Fife.
Forth defence lines
In the First World War three lines of defence were established on the Firth of Forth to protect Rosyth Naval Dockyard, then home to the Battle Cruiser Fleet. These lines of defence were known as the Outer, Middle and Inner Defence Lines.
The Outer Line ran from a gun battery at Kinghorn to a battery at Leith Docks, with fortified gun emplacements on the island of Inchkeith.
The Middle Line of defence ran from Braefoot Battery in the North to a battery on Cramond Island in the South, with fortified gun emplacements on the islands of Inchcolm and Inchmickery.
The Inner Line of defence was situated close to the Forth Bridge, with batteries at Downing Point on the North coast and Hound Point on the South coast of the river. Additional batteries were located at Carlingnose Point, Dalmeny, and on the island of Inchgarvie. Each line of defence also had an associated anti-submarine boom.
Battery specification
The Braefoot Battery was equipped with two large calibre naval gun emplacements, designed to engage any large enemy surface vessels threatening ships at anchor in the Firth of Forth and the naval facilities at Rosyth Dockyard. Each gun emplacement housed a BL 9.2-inch Mk IX – X naval gun which could fire a shell weighing 55 kg out to range of 26 km.
The battery was manned by local men of the Territorial Royal Garrison Artillery
The coast guns were such an important part of the defence of the country that considerable efforts were made to protect them from landings of enemy troops that might put them out of action. The battery had a defended perimeter comprising, from inside out, a firing trench, a 10 foot high 'palisade' fence, and a barbed wire entanglement. The |
https://en.wikipedia.org/wiki/ERMETH | The ERMETH (Electronic Calculating Machine of the ETH) was one of the first computers in Europe and was developed and built by Eduard Stiefel and his team of the Institute for Applied Mathematics at the ETH Zurich between 1948 and 1956. It was in use until 1963 and is now displayed at the Museum of Communication Bern (Switzerland).
Models
Eduard Stiefel and his two senior assistants Heinz Rutishauser and Ambros Speiser were inspired by models in the USA and United Kingdom when developing the ERMETH. In 1949 Rutishauser and Speiser undertook study trips to Howard Aiken (Harvard University), John von Neumann (Princeton University) and to the University of Cambridge, which operated the EDSAC. In 1950, Stiefel rented for five years the only existing digital computer in continental Europe at that time, the Zuse Z4, completed by Konrad Zuse in 1945, for the ETH in order to gain experience with a calculating machine during the construction of the ERMETH.
Technical concept
The ERMETH had (in contrast to the Z4) a classical von Neumann architecture, i.e. it was a calculating machine in which program and processed data were stored in the same main memory; thus, numbers, as well as program parts, could be processed automatically. The ERMETH was designed for numerical calculations and worked in true decimal (not dual or hexadecimal) and had instructions for all four basic arithmetic operations with floating-point and fixed-point numbers, but not for processing letters. At the start of operation (1956), it consisted of devices (hardware) and stored user programs (software), but had no operating system, so that each user had to first read in his program, which had already been prepared on punch cards in machine language and then start it by setting the program counter to the first command. Under program control, user data was then read in (from punch cards) and parameter values were requested (via the keyboard) from the user.
Already in 1952, Heinz Rutishauser had presente |
https://en.wikipedia.org/wiki/List%20of%20taxa%20named%20by%20anagrams | In the biological nomenclature codes, an anagram can be used to name a new taxon.
Wordplays are one source of inspiration allowing organisms to receive scientific names. In the binomial nomenclature, as scientists have latitude in naming genera and species, a taxon name can therefore be an anagram, provided it remains pronounceable. For example, in the International Code of Nomenclature for algae, fungi, and plants, a new generic name can be taken from the name of a person by using an anagram or abbreviation of it.
William Elford Leach was among the first naturalists to use taxonomic anagrams, and, in 1818, he described several isopod genera that were
each other's anagrams of 'Caroline' : Conilera, Lironeca, Nerocila, Olencira, and Rocinela.
List in botany
Notes
References
Taxonomic lists
Taxonomy (biology)
Taxa
Lists of things named after people
Biological nomenclature
Nomenclature codes |
https://en.wikipedia.org/wiki/Addressed%20fiber%20Bragg%20structure | An addressed fiber Bragg structure (AFBS) is a fiber Bragg grating, the optical frequency response of which includes two narrowband components with the frequency spacing between them (which is the address frequency of the AFBS) being in the radio frequency (RF) range. The frequency spacing (the address frequency) is unique for every AFBS in the interrogation circuit and does not change when the AFBS is subjected to strain or temperature variation. An addressed fiber Bragg structure can perform triple function in fiber-optic sensor systems: a sensor, a shaper of double-frequency probing radiation, and a multiplexor. The key feature of AFBS is that it enables the definition of its central wavelength without scanning its spectral response, as opposed to conventional fiber Bragg gratings (FBG), which are probed using optoelectronic interrogators. An interrogation circuit of AFBS is significantly simplified in comparison with conventional interrogators and consists of a broadband optical source (such as a superluminescent diode), an optical filter with a predefined linear inclined frequency response, and a photodetector. The AFBS interrogation principle intrinsically allows to include several AFBSs with the same central wavelength and different address frequencies into a single measurement system.
History
The concept of addressed fiber Bragg structures was introduced in 2018 by Airat Sakhabutdinov and developed in collaboration with his scientific adviser, Oleg Morozov. The idea emerged from the earlier works of Morozov and his colleagues, where the double-frequency optical radiation from an electro-optic modulator was used for the definition of the FBG central wavelength based on the amplitude and phase analysis of the beating signal at the frequency equal to the spacing between the two components of the probing radiation. This eliminates the need for scanning the FBG spectral response while providing high accuracy of measurements and reducing the system cost. AFBS ha |
https://en.wikipedia.org/wiki/Biodiversity%20and%20conservation%20in%20Manitoba | Manitoba is home to a variety of ecosystems across the province that need to be considered in development and conservation plans. There are terrestrial ecosystems, which includes prairies, boreal forest, and tundra. Manitoba is also the home to a number of aquatic ecosystems, including wetlands, rivers, and lakes. There is also a wide variety of wildlife and plants that thrive in this particular region. However, human impact has become more apparent and the need to protect and conserve is becoming clear.
The Province of Manitoba created a protection act in March 1990 called The Endangered Species Ecosystem Act. The Act protects animals, plants, and ecosystems by supporting and monitoring development at a provincial level. This includes monitoring the land use, protection areas, planning, environmental assessment, and natural resources harvesting policies by incorporating the biodiversity values in their decision making.
In June 2003, the federal government created the Species at Risk Act (SARA). The Act is to prevent wildlife species in Canada from disappearing, provide recovery of wildlife species that are endangered or threatened as a result of human activity, and prevent future loss of species (Canada.ca, 2020). A key component of the success of SARA is the participation of other levels of government to contribute in enforcing and protecting wildlife. Consulting and having cooperation of aboriginal communities and all stakeholders that may be affected in the protection of wildlife is another component of the Act's success. There are a number of Manitoban species on the SARA list that are now protected at a federal level, which will help reinforce their safety.
More information about what Manitoba is doing to help protect the environment apart from biodiversity can be found on their website. The website highlights a number of subcategories of concerns regarding the environment, including:
Invasive species
Air quality management
Climate change
Pollution prev |
https://en.wikipedia.org/wiki/Downing%20Point%20Battery | The Downing Point Battery was a World War I coastal gun battery defending the Firth of Forth. The battery was constructed in 1914 at Downing Point, then part of the Earl of Moray's Donibristle Estate. The site is now situated within the new town of Dalgety Bay in Fife.
Forth defence lines
In the First World War three lines of defence were established on the Firth of Forth to protect Rosyth Naval Dockyard, then home to the Battle Cruiser Fleet. These lines of defence were known as the Outer, Middle and Inner Defence Lines.
The Outer Line ran from a gun battery at Kinghorn to a battery at Leith Docks, with fortified gun emplacements on the island of Inchkeith.
The Middle Line ran from Braefoot Battery in the North to a battery on Cramond Island in the South, with fortified gun emplacements on the islands of Inchcolm and Inchmickery.
The Inner Line was situated close to the Forth Bridge, with batteries at Downing Point on the North coast and Hound Point on the South coast of the firth. Additional batteries were located at Carlingnose Point, Dalmeny, and on the island of Inchgarvie. Each line of defence also had an associated anti-submarine boom.
Battery specification
The Downing Point Battery incorporated two gun emplacements, each was initially equipped with a QF 4.7-inch Mk I – IV naval gun, designed to engage enemy surface vessels threatening ships at anchor in the Firth of Forth and the naval facilities at Rosyth Dockyard. Each 4.7 inch gun could fire a shell weighing 20 kg out to range of 11 km.
In June 1917 the two 4.7 inch guns were transferred to the battery on Inchcolm Island and replaced with two QF 12-pounder 18 cwt naval guns taken from the island. These 12-pounder guns could fire a 5 kg shell out to a range of 8.5 km.
A thin promontory of rock runs to the East from gun emplacements, this promontory housed two Defence Electric Lights – powerful searchlights designed to illuminate targets for the guns at night. One DEL was of the kind where the ligh |
https://en.wikipedia.org/wiki/Crossing%20Numbers%20of%20Graphs | Crossing Numbers of Graphs is a book in mathematics, on the minimum number of edge crossings needed in graph drawings. It was written by Marcus Schaefer, a professor of computer science at DePaul University, and published in 2018 by the CRC Press in their book series Discrete Mathematics and its Applications.
Topics
The main text of the book has two parts, on the crossing number as traditionally defined and on variations of the crossing number, followed by two appendices providing background material on topological graph theory and computational complexity theory.
After introducing the problem, the first chapter studies the crossing numbers of complete graphs (including Hill's conjectured formula for these numbers) and complete bipartite graphs (Turán's brick factory problem and the Zarankiewicz crossing number conjecture), again giving a conjectured formula). It also includes the crossing number inequality, and the Hanani–Tutte theorem on the parity of crossings. The second chapter concerns other special classes of graphs including graph products (especially products of cycle graphs) and hypercube graphs. After a third chapter relating the crossing number to graph parameters including skewness, bisection width, thickness, and (via the Albertson conjecture) the chromatic number, the final chapter of part I concerns the computational complexity of finding minimum-crossing graph drawings, including the results that the problem is both NP-complete and fixed-parameter tractable.
In the second part of the book, two chapters concern the rectilinear crossing number, describing graph drawings in which the edges must be represented as straight line segments rather than arbitrary curves, and Fáry's theorem that every planar graph can be drawn without crossings in this way. Another chapter concerns 1-planar graphs and the associated local crossing number, the smallest number such that the graph can be drawn with at most crossings per edge. Two chapters concern book embedd |
https://en.wikipedia.org/wiki/Low%20Frequency%20Analyzer%20and%20Recorder | Two closely related terms, Low Frequency Analyzer and Recorder and Low Frequency Analysis and Recording bearing the acronym LOFAR, deal with the equipment and process respectively for presenting a visual spectrum representation of low frequency sounds in a time–frequency analysis. The process was originally applied to fixed surveillance passive antisubmarine sonar systems and later to sonobuoy and other systems. Originally the analysis was electromechanical and the display was produced on electrostatic recording paper, a Lofargram, with stronger frequencies presented as lines against background noise. The analysis migrated to digital and both analysis and display were digital after a major system consolidation into centralized processing centers during the 1990s.
Both the equipment and process had specific and classified application to fixed surveillance sonar systems and was the basis for the United States Navy's ocean wide Sound Surveillance System (SOSUS) established in the early 1950s. The research and development of systems utilizing LOFAR was given the code name Project Jezebel. The installation and maintenance of SOSUS was under the unclassified code name Project Caesar. The principle was later applied to air, surface and submarine tactical sonar systems with some incorporating the name "Jezebel".
Origin
In 1949 when the US Navy approached the Committee for Undersea Warfare, an academic advisory group formed in 1946 under the National Academy of Sciences, to research antisubmarine warfare. As a result, the Navy formed a study group designated Project Hartwell under Massachusetts Institute of Technology (MIT) leadership. The Hartwell panel recommended that spending of annually to develop systems to counter the Soviet submarine threat consisting primarily of a large fleet of diesel submarines. One recommendation was a system to monitor low-frequency sound in the SOFAR channel using multiple listening sites equipped with hydrophones and a processing facility |
https://en.wikipedia.org/wiki/Comparison%20of%20Gaussian%20process%20software | This is a comparison of statistical analysis software that allows doing inference with Gaussian processes often using approximations.
This article is written from the point of view of Bayesian statistics, which may use a terminology different from the one commonly used in kriging. The next section should clarify the mathematical/computational meaning of the information provided in the table independently of contextual terminology.
Description of columns
This section details the meaning of the columns in the table below.
Solvers
These columns are about the algorithms used to solve the linear system defined by the prior covariance matrix, i.e., the matrix built by evaluating the kernel.
Exact: whether generic exact algorithms are implemented. These algorithms are usually appropriate only up to some thousands of datapoints.
Specialized: whether specialized exact algorithms for specific classes of problems are implemented. Supported specialized algorithms may be indicated as:
Kronecker: algorithms for separable kernels on grid data.
Toeplitz: algorithms for stationary kernels on uniformly spaced data.
Semisep.: algorithms for semiseparable covariance matrices.
Sparse: algorithms optimized for sparse covariance matrices.
Block: algorithms optimized for block diagonal covariance matrices.
Markov: algorithms for kernels which represent (or can be formulated as) a Markov process.
Approximate: whether generic or specialized approximate algorithms are implemented. Supported approximate algorithms may be indicated as:
Sparse: algorithms based on choosing a set of "inducing points" in input space, or more in general imposing a sparse structure on the inverse of the covariance matrix.
Hierarchical: algorithms which approximate the covariance matrix with a hierarchical matrix.
Input
These columns are about the points on which the Gaussian process is evaluated, i.e. if the process is .
ND: whether multidimensional input is supported. If it is, multidimens |
https://en.wikipedia.org/wiki/Descriptive%20Complexity | Descriptive Complexity is a book in mathematical logic and computational complexity theory by Neil Immerman. It concerns descriptive complexity theory, an area in which the expressibility of mathematical properties using different types of logic is shown to be equivalent to their computability in different types of resource-bounded models of computation. It was published in 1999 by Springer-Verlag in their book series Graduate Texts in Computer Science.
Topics
The book has 15 chapters, roughly grouped into five chapters on first-order logic, three on second-order logic, and seven independent chapters on advanced topics.
The first two chapters provide background material in first-order logic (including first-order arithmetic, the BIT predicate, and the notion of a first-order query) and complexity theory (including formal languages, resource-bounded complexity classes, and complete problems). Chapter three begins the connection between logic and complexity, with a proof that the first-order-recognizable languages can be recognized in logarithmic space, and the construction of complete languages for logarithmic space, nondeterministic logarithmic space, and polynomial time. The fourth chapter concerns inductive definitions, fixed-point operators, and the characterization of polynomial time in terms of first-order logic with the least fixed-point operator. The part of the book on first-order topics ends with a chapter on logical characterizations of resource bounds for parallel random-access machines and circuit complexity.
Chapter six introduces Ehrenfeucht–Fraïssé games, a key tool for proving logical inexpressibility, and chapter seven introduces second-order logic. It includes Fagin's theorem characterizing nondeterministic polynomial time in terms of existential second-order logic, the Cook–Levin theorem on the existence of NP-complete problems, and extensions of these results to the polynomial hierarchy. Chapter eight uses games to prove the inexpressibility o |
https://en.wikipedia.org/wiki/Redundancy%20principle%20%28biology%29 | The redundancy principle in biology expresses the need of many copies of the same entity (cells, molecules, ions) to fulfill a biological function. Examples are numerous: disproportionate numbers of spermatozoa during fertilization compared to one egg, large number of neurotransmitters released during neuronal communication compared to the number of receptors, large numbers of released calcium ions during transient in cells, and many more in molecular and cellular transduction or gene activation and cell signaling. This redundancy is particularly relevant when the sites of activation are physically separated from the initial position of the molecular messengers. The redundancy is often generated for the purpose of resolving the time constraint of fast-activating pathways. It can be expressed in terms of the theory of extreme statistics to determine its laws and quantify how the shortest paths are selected. The main goal is to estimate these large numbers from physical principles and mathematical derivations.
When a large distance separates the source and the target (a small activation site), the redundancy principle explains that this geometrical gap can be compensated by large number. Had nature used less copies than normal, activation would have taken a much longer time, as finding a small target by chance is a rare event and falls into narrow escape problems.
Molecular rate
The time for the fastest particles to reach a target in the context of redundancy depends on the numbers and the local geometry of the target. In most of the time, it is the rate of activation. This rate should be used instead of the classical Smoluchowski's rate describing the mean arrival time, but not the fastest. The statistics of the minimal time to activation set kinetic laws in biology, which can be quite different from the ones associated to average times.
Physical models
Stochastic process
The motion of a particle located at position can be described by the Smoluchowski's limit |
https://en.wikipedia.org/wiki/Positive%20linear%20operator | In mathematics, more specifically in functional analysis, a positive linear operator from an preordered vector space into a preordered vector space is a linear operator on into such that for all positive elements of that is it holds that
In other words, a positive linear operator maps the positive cone of the domain into the positive cone of the codomain.
Every positive linear functional is a type of positive linear operator.
The significance of positive linear operators lies in results such as Riesz–Markov–Kakutani representation theorem.
Definition
A linear function on a preordered vector space is called positive if it satisfies either of the following equivalent conditions:
implies
if then
The set of all positive linear forms on a vector space with positive cone called the dual cone and denoted by is a cone equal to the polar of
The preorder induced by the dual cone on the space of linear functionals on is called the .
The order dual of an ordered vector space is the set, denoted by defined by
Canonical ordering
Let and be preordered vector spaces and let be the space of all linear maps from into
The set of all positive linear operators in is a cone in that defines a preorder on .
If is a vector subspace of and if is a proper cone then this proper cone defines a on making into a partially ordered vector space.
If and are ordered topological vector spaces and if is a family of bounded subsets of whose union covers then the positive cone in , which is the space of all continuous linear maps from into is closed in when is endowed with the -topology.
For to be a proper cone in it is sufficient that the positive cone of be total in (that is, the span of the positive cone of be dense in ).
If is a locally convex space of dimension greater than 0 then this condition is also necessary.
Thus, if the positive cone of is total in and if is a locally convex space, then the canonical ordering of define |
https://en.wikipedia.org/wiki/Cursed%20image | A cursed image refers to a picture (usually a photograph) that is perceived as mysterious or disturbing due to its content, poor quality, or a combination of the two. A cursed image is intended to make a person question the reason for the image's existence in the first place. The term was coined on social media in 2015 and popularised the following year.
History
The concept of "cursed images" originates from a Tumblr blog, cursedimages, in 2015. The first image posted by the account shows an elderly farmer surrounded by crates of red tomatoes in a wood-paneled room. In a 2019 interview with Paper, the blog's owner described the aforementioned image as follows: "It's the perfect cursed image to me because there's nothing inherently unsettling about any part of it. It's a totally mundane moment transformed into something else by the camera and the new context I've given it."
While the term "cursed image" had been used on Tumblr since 2015, it became more widely popularized by July 2016 due to the Twitter account @cursedimages. In a 2016 interview with Gizmodo writer Hudson Hongo, the owner of the account explained that he had seen "one or two" posts on Tumblr containing "unexplainable and odd" pictures that were simply captioned "cursed image". Intrigued by the pictures, the owner of the account began searching for similar images and after finding more photographs in that vein, decided to "post them all in one place". That same year, Brian Feldman of New York magazine interviewed Doug Battenhausen, the owner of the Tumblr blog internethistory, which also posts "cursed images". Feldman asked Battenhausen about the appeal of "cursed images", to which Battenhausen replied: "It's a lot of things. It's the mystery of the photo, it's the strange aesthetics of them, it's seeing a place that you've never seen before, or an intimate glimpse into somebody's life."
Feldman attributes the "cursed" aesthetic to the nature of digital photography in the early 2000s, where point-a |
https://en.wikipedia.org/wiki/The%20Geometry%20of%20Musical%20Rhythm | The Geometry of Musical Rhythm: What Makes a "Good" Rhythm Good? is a book on the mathematics of rhythms and drum beats. It was written by Godfried Toussaint, and published by Chapman & Hall/CRC in 2013 and in an expanded second edition in 2020. The Basic Library List Committee of the Mathematical Association of America has suggested its inclusion in undergraduate mathematics libraries.
Author
Godfried Toussaint (1944–2019) was a Belgian–Canadian computer scientist who worked as a professor of computer science for McGill University and New York University. His main professional expertise was in computational geometry, but he was also a jazz drummer, held a long-term interest in the mathematics of music and musical rhythm, and since 2005 held an affiliation as a researcher in the Centre for Interdisciplinary Research in Music Media and Technology in the Schulich School of Music at McGill. In 2009 he visited Harvard University as a Radcliffe Fellow in advancement of his research in musical rhythm.
Topics
In order to study rhythms mathematically, Toussaint abstracts away many of their features that are important musically, involving the sounds or strengths of the individual beats, the phasing of the beats, hierarchically-structured rhythms, or the possibility of music that changes from one rhythm to another. The information that remains describes the beats of each bar (an evenly-spaced cyclic sequence of times) as being either on-beats (times at which a beat is emphasized in the musical performance) or off-beats (times at which it is skipped or performed only weakly). This can be represented combinatorially as a necklace, an equivalence class of binary sequences under rotations, with true binary values representing on-beats and false representing off-beats. Alternatively, Toussaint uses a geometric representation as a convex polygon, the convex hull of a subset of the vertices of a regular polygon, where the vertices of the hull represent times when a beat is perform |
https://en.wikipedia.org/wiki/Unix%20Expo | Unix Expo was a conference and trade show that focused on the Unix operating system, and software based on Unix, in the information technology sector. It ran from 1984 through 1996 and was held in New York City during the autumn season. The show was owned and managed by the Blenheim Group.
Origins
The first Unix Expo was held in October 1984 and was split between the Sheraton Centre Hotel and the Marina Expo complex in New York and had the formal title of Unix Operating System Exposition & Conference. It was organized by the Unigroup users' group for Unix, and some seventy Unix-related vendors signed up to display at it.
The shows
AT&T Corporation, owner of Bell Labs, the creator of Unix, was the company behind the early commercial push for Unix adoption; accordingly it had the anchor display position in early shows. By 1987, in its fourth year, the show had some 16,000 attendees, with commercial interest rising in Unix due to its portability and strengths in development tools and networking. Due to acquisitions of various promotions firms, the show was run under the names of several different companies, ending with the Blenheim Group.
The show grew in significance; in 1985 it was where AT&T unveiled Xenix System V, and in 1989 it was the site of AT&T's unveiling of the much-talked-about System V Release 4 version of Unix. Similarly, it was a site where discussions to end the divisive Unix wars could take place. Numerous other product announcements and company alliances were also announced during a Unix Expo.
In its peak years, the show was held within the Javits Center and had upwards of 35,000 attendees. Along with Uniforum in San Francisco in the spring, Unix Expo was considered one of the two big Unix-themed trade shows and conferences that one could attend during a year. The show featured keynote addresses by the likes of Oracle Corporation head Larry Ellison, O'Reilly Media founder Tim O'Reilly, the Santa Cruz Operation CEO Alok Mohan, and Sun M |
https://en.wikipedia.org/wiki/Reproductive%20interference | Reproductive interference is the interaction between individuals of different species during mate acquisition that leads to a reduction of fitness in one or more of the individuals involved. The interactions occur when individuals make mistakes or are unable to recognise their own species, labelled as ‘incomplete species recognition'. Reproductive interference has been found within a variety of taxa, including insects, mammals, birds, amphibians, marine organisms, and plants.
There are seven causes of reproductive interference, namely signal jamming, heterospecific rivalry, misdirected courtship, heterospecific mating attempts, erroneous female choice, heterospecific mating, and hybridisation. All types have fitness costs on the participating individuals, generally from a reduction in reproductive success, a waste of gametes, and the expenditure of energy and nutrients. These costs are variable and dependent on numerous factors, such as the cause of reproductive interference, the sex of the parent, and the species involved.
Reproductive interference occurs between species that occupy the same habitat and can play a role in influencing the coexistence of these species. It differs from competition as reproductive interference does not occur due to a shared resource. Reproductive interference can have ecological consequences, such as through the segregation of species both spatially and temporally. It can also have evolutionary consequences, for example; it can impose a selective pressure on the affected species to evolve traits that better distinguish themselves from other species.
Causes of reproductive interference
Reproductive interference can occur at different stages of mating, from locating a potential mate, to the fertilisation of an individual of a different species. There are seven causes of reproductive interference that each have their own consequences on the fitness of one or both of the involved individuals.
Signal jamming
Signal jamming refers to t |
https://en.wikipedia.org/wiki/Ant%20garden | An ant garden is a mutualistic interaction between certain species of arboreal ants and various epiphytic plants. It is a structure made in the tree canopy by the ants that is filled with debris and other organic matter in which epiphytes grow. The ants benefit from this arrangement by having a stable framework on which to build their nest while the plants benefit by obtaining nutrients from the soil and from the moisture retained there.
Description
Epiphytes are common in tropical rain forest and in cloud forest. An epiphyte normally derives its moisture and nutrients from the air, rain, mist and dew. Nitrogenous matter is in short supply and the epiphytes benefit significantly from the nutrients in the ant garden. The ant garden is made from "carton", a mixture of vegetable fibres, leaf debris, refuse, glandular secretions and ant faeces. The ants use this material to build their nests among the branches of the trees, to shelter the hemipteran insects that they tend in order to feed on their honeydew, and to make the pockets of material in which the epiphytes grow.
The ants harvest seeds from the epiphytic plants and deposit them in the carton material. The plants have evolved various traits to encourage ants to disperse their seeds by producing chemical attractants. Eleven unrelated epiphytes that grow in ant gardens have been found to contain methyl salicylate (oil of wintergreen) and it seems likely that this compound is an ant attractant.
Examples
Species of ant that make gardens include Crematogaster carinata, Camponotus femoratus and Solenopsis parabioticus, all of which are parabiotic species which routinely share their nests with unrelated species of ant. Epiphytic plants that they grow include various members of the Araceae, Bromeliaceae, Cactaceae, Gesneriaceae, Moraceae, Piperaceae and Solanaceae. Epiphytic plants in the genus Codonanthopsis, including those formerly placed in Codonanthe, grow almost exclusively in ant gardens, often associated with |
https://en.wikipedia.org/wiki/Verbose%20mode | In computing, Verbose mode is an option available in many computer operating systems and programming languages that provides additional details as to what the computer is doing and what drivers and software it is loading during startup or in programming it would produce detailed output for diagnostic purposes thus makes a program easier to debug.
When running programs in the command line, verbose output is typically outputted in standard output or standard error.
Many command line programs can be set to verbose mode by using a flag, such as or . Such a program is cURL.
References
Software features
Debugging |
https://en.wikipedia.org/wiki/The%20Petersen%20Graph | The Petersen Graph is a mathematics book about the Petersen graph and its applications in graph theory. It was written by Derek Holton and John Sheehan, and published in 1993 by the Cambridge University Press as volume 7 in their Australian Mathematical Society Lecture Series.
Topics
The Petersen graph is an undirected graph with ten vertices and fifteen edges, commonly drawn as a pentagram within a pentagon, with corresponding vertices attached to each other. It has many unusual mathematical properties, and has frequently been used as a counterexample to conjectures in graph theory. The book uses these properties as an excuse to cover several advanced topics in graph theory where this graph plays an important role. It is heavily illustrated, and includes both open problems on the topics it discusses and detailed references to the literature on these problems.
After an introductory chapter, the second and third chapters concern graph coloring, the history of the four color theorem for planar graphs, its equivalence to 3-edge-coloring of planar cubic graphs, the snarks (cubic graphs that have no such colorings), and the conjecture of W. T. Tutte that every snark has the Petersen graph as a graph minor. Two more chapters concern closely related topics, perfect matchings (the sets of edges that can have a single color in a 3-edge-coloring) and nowhere-zero flows (the dual concept to planar graph coloring). The Petersen graph shows up again in another conjecture of Tutte, that when a bridgeless graph does not have the Petersen graph as a minor, it must have a nowhere-zero 4-flow.
Chapter six of the book concerns cages, the smallest regular graphs with no cycles shorter than a given length. The Petersen graph is an example: it is the smallest 3-regular graph with no cycles of length shorter than 5. Chapter seven is on hypohamiltonian graphs, the graphs that do not have a Hamiltonian cycle through all vertices but that do have cycles through every set of all but one v |
https://en.wikipedia.org/wiki/Doho%20Rice%20Scheme | Doho Rice Scheme is an irrigation rice scheme found in Butaleja District, Eastern Uganda. Rice production in Doho started in 1942 to feed World War II soldiers. After the war, production declined until 1972. However, after several constraints to the scheme including flooding of River Manafwa and scarcity of irrigation water during the dry season, the farmers appealed for Government of Uganda intervention.
In 1976, the scheme was officially established by the government with funding from the Chinese government which was completed in 1984. Doho rice scheme is a 2500 Hectares irrigation scheme, sustaining not less than 10,000 farmers both out-growers and part of the scheme's growers. Most of the scheme was formerly a seasonal wetland on the River Manafwa flood-plain. The scheme is now an area of intensive irrigated rice cultivation with adjacent areas of natural wetland, mainly in the south. The Doho Irrigation Scheme Farmers Cooperative Society (DIFACOS) is the umbrella body set up to manage the scheme.
Location
Doho Rice Irrigation Scheme spans in both Mazimasa and Kachonga Sub-Counties of East Bunyole County in Butaleja District of Uganda. It is 49 km from Tororo town, 25 km from Mbale town and 260 km from Kampala city and 70 km from Malaba, Uganda-Kenya border. Doho Rice Scheme is located in the Lake Kyoga basin and covers an area of 494.2 km2.
See also
Butaleja District
Government of Uganda
References
Butaleja District
Rice production
Irrigation projects
1976 establishments in Nigeria
Farms in Nigeria
Important Bird Areas of Uganda |
https://en.wikipedia.org/wiki/Phosphorimidazolide | A phosphorimidazolide is a chemical compound in which a phosphoryl mono-ester is covalently bound to a nitrogen atom in an imidazole ring. They are a type of phosphoramidate. These phosphorus (V) compounds are encountered as reagents used for making new phosphoanhydride bonds with phosphate mono-esters, and as reactive intermediates in phosphoryl transfer reactions in some enzyme-catalyzed transformations. They are also being studied as critical chemical intermediates for the polymerization of nucleotides in pre-biotic settings. They are sometimes referred to as phosphorimidazolidates, imidazole-activated phosphoryl groups, and P-imidazolides.
Role in Oligonucleotide Formation
Phosphorimidazolides have been investigated for their mechanistic role in abiogenesis (the natural process by which life arose from non-living matter). Specifically, they have been proposed as the active electrophilic species which may have mediated the formation of inter-nucleotide phosphodiester bonds, thereby enabling template-directed oligonucleotide replication before the advent of enzymes. Phosphorimidazolides were originally proposed as mediators of this process by Leslie Orgel in 1968. Early studies showed that divalent metal cations such as Mg2+, Zn2+, and Pb2+ and a complimentary template were required for the formation of short oligonucleotides, although nucleotides exhibited 5'-2' connectivity instead of 5'-3' connectivity of present-day life forms. It was also shown that Montmorillonite clay could provide a surface for phosphorimidazolide-mediated oligonucleotide formation with lengths of 20-50 bases.
The research group of Jack W. Szostak has continued to investigate the role of phosphorimidazolides in pre-biotic nucleotide polymerization. The group has investigated a number of imidazole derivatives in the search for chemical moieties which provide longer oligonucleotides necessary for propagating genetic information. Significantly, they discovered that phosphorimidazolides pro |
https://en.wikipedia.org/wiki/ITF-6 | ITF-6 is the implementation of an Interleaved 2 of 5 (ITF) barcode to encode a addon to ITF-14 and ITF-16 barcodes. Originally was developed as a part of JIS specification for Physical Distribution Center. Instead of ITF-14, it wasn’t standardized by ISO Committee but it is widely used to encode additional data to Global Trade Item Number such as items quantity or container weight.
History
In 1983, the Logistics Symbol Committee proposed the Interleaved 2 of 5 barcode as a method to improve the JAN code. In 1985, a logistics symbol JIS drafting committee was set up at the Distribution System Development Center, and the final examination was started toward JIS. Then in 1987 it was standardized as JIS-X-0502, a standard physical distribution barcode symbol ITF-14/16/6.
The ITF barcode has an add-on version for displaying the weight, etc., and it is possible to encode a 5-digits numerical value and 6-th check character as ITF-6 after ITF-14 or ITF-16(obsolete in 2010).
Currently ITF-6 isn’t standardized by ISO Committee and it is used only as a part of JIS standards. However, it is widely used by manufacturers to encode additional data and it is supported by wide range of barcode scanners
Uses
Despite the fact that ITF-6 barcode isn’t included into ISO standards, it is widely used as add-on to encode items quantity in package or item weight. At this time, it is used only with ITF-14 (Global Trade Item Number), but up to 2010 it was used with standardized only in Japan ITF-16 (Extended Symbology for Physical Distribution).
From the left, ITF-6 contains 5 significant digits and the last one is control digit, which is calculated same way as UPC checksums. If a decimal point is required, the decimal point is between the 3rd and 4th digits:
NNNNN(C/D) - without decimal point;
NNN.NN(C/D) - with decimal point.
ITF-6 is supported by various barcode generating software and barcode scanners.
Checksum
Checksum is calculated as other UPC checksums:
Example for the first |
https://en.wikipedia.org/wiki/Avalanche%20%28blockchain%20platform%29 | Avalanche is a decentralized, open-source proof of stake blockchain with smart contract functionality. AVAX is the native cryptocurrency of the platform.
History
Avalanche began as a protocol for solving for consensus in a network of unreliable machines, where failures may be crash-fault or Byzantine. The protocol's fundamentals were first shared on the InterPlanetary File System (IPFS) in May 2018 by a pseudonymous group of enthusiasts going by the name "Team Rocket".
Avalanche was later developed by researchers from Cornell University led by Emin Gün Sirer and doctoral students Maofan "Ted" Yin and Kevin Sekniqi. Following the research stage, a startup technology company was founded to develop a blockchain network that would meet finance industry requirements. In March, 2020, the AVA codebase (Developer Accelerator Program or AVA DAP) for the Avalanche consensus protocol was released as open-source and became available to the public.
In September, 2020, the company also issued its native token Avax.
In September 2021, the Ava labs foundation received a $230 million investment from a group consisting of Polychain and Three Arrows Capital, through the purchase of the AVAX cryptocurrency.
In November 2021, following an agreement with Deloitte to improve U.S. disaster-relief funding, the Avalanche blockchain moved into the top 10 cryptocurrencies in terms of capitalization.
In August 2022, whistleblower "Crypto Leaks" published a report accusing Ava Labs of secret deals with a law firm aimed at legally destabilizing Avalanche's competitors. Ava Labs CEO Emin Gün Sirer denied any sort of illegal or unethical deal with Roche Freedmen law firm.
In January 2023, a partnership was announced between Avalanche and Amazon to improve Avalanche's infrastructure and decentralized application ecosystem.
In February 2023, Indian game streaming platform Loco teamed up with the Avalanche blockchain.
Design
AVAX
Avalanche (AVAX) is the native token of Avalanche, traded o |
https://en.wikipedia.org/wiki/Alpha%20Nu%20Sigma | Alpha Nu Sigma () is an American nuclear engineering honor society affiliated with the American Nuclear Society. Alpha Nu Sigma was established to "recognize high scholarship, integrity, and potential achievement among outstanding degree-seeking nuclear engineering students at institutions of higher learning". As of fall 2021, there are 18 active chapters and approximately 2,000 members nationwide.
History
Alpha Nu Sigma National Honor Society was established by the American Nuclear Society on June 5, 1979. Alpha Nu Sigma quickly grew in size, obtaining 17 chapters and 320 members by its third anniversary in June 1982. By the end of 1985, Alpha Nu Sigma had grown to 23 chapters and 920 members. The Chernobyl disaster occurred in 1986, and growth of the society has struggled since that event.
Symbols
The motto of Alpha Nu Sigma is "Energy Newly Born Through Wisdom". The symbol of Alpha Nu Sigma contains "three ellipses representing electron orbits surrounding a nucleus of protons and neutrons" with the Greek letters of the society superimposed.
Membership
Membership selection criteria for Alpha Nu Sigma are outlined in the national honor society's constitution. The criteria are summarized as follows:
Candidates for membership must be enrolled in a program to pursue an academic degree in an applied-nuclear-science, nuclear-engineering, or nuclear-engineering option curriculum.
Juniors shall be eligible if they rank in the top quarter of their peer group.
Seniors and graduate students shall be eligible if they rank in the top third of their peer group.
Faculty members shall also be eligible for membership.
Honorary membership may be awarded to individuals who have made "exemplary contributions in the field of nuclear science and engineering that have had seminal permanent impact nationally or internationally".
Chapter list
As of fall 2021, the following table lists the chapters of Alpha Nu Sigma.
Honorary members
As of spring 2020, the following table li |
https://en.wikipedia.org/wiki/Questrade | Questrade is an online brokerage firm and wealth management firm based in Canada. It is Canada's largest discount broker.
Products and services
The company was created by Edward Kholodenko with three partners and launched in 1999. As of early 2020, the company was Canada's fastest growing online brokerage firm, and has $20 billion under management, as of February 2021. Questrade has expanded to include robo-advising with its Questwealth Portfolios, which invests in portfolios based on ETFs. In December 2019, Questrade applied for a banking license signalling its intent to offer banking services.
References
External links
Robo-advisors
Financial services companies established in 1999
Online services
Online brokerages
Investment companies of Canada
Financial services companies of Canada
Companies based in Toronto
1999 establishments in Ontario |
https://en.wikipedia.org/wiki/Packard%20Bell%20Statesman | The Packard Bell Statesman was an economy line of notebook computers introduced in 1993 by Packard Bell. They were slower in performance and lacked features compared to most competitor products, but they were lower in price. It was created in a collaboration between Packard Bell and Zenith Data Systems. The Statesman series was essentially a rebrand of Zenith Data Systems Z-Star 433 series, with the only notable difference of the logo in the middle and text on the front bezel.
History
In June 1993 Zenith Data Systems announced an alliance with Packard Bell. Zenith acquired about 20% of Packard Bell and they would both now work together to design and build PC's. Zenith would also provide Packard Bell with private-label versions of their portable PC's. The Packard Bell Statesman was a rebrand of the Zenith Z-Star notebook computer series. While the Statesman was being advertised by Packard Bell, the Z-Star series was also still being sold by Zenith.
The Statesman was first introduced on October 4, 1993. Prices started at $1,500 for a monochrome or color DSTN model with a 33 MHz Cyrix Cx486SLC, 4 MB of RAM, 200 MB hard disk drive, internal 1.44 MB floppy disk drive, and MS-DOS 6.0 with Windows 3.1 for the included software. A "J mouse" pointing device was included, similar to the TrackPoint. The Statesman was expected to begin shipping within the next few weeks.
Specifications
Hardware
CPU
The first two models, the 200M and 200C, used the Cyrix Cx486SLC. This was Cyrix's first processor, which was actually a 386SX with on-board L1 cache and 486 instructions, being known as a "hybrid chip". The processor was clocked at 33 MHz and had 1 KB of L1 cache. It was a 16-bit processor and was pin compatible with the Intel 80386SX. On the bottom of the unit, the motherboard had an empty socket for a Cyrix FasMath co-processor, which could improve floating-point math performance.
The 200M and 200C plus models had a Cyrix Cx486SLC2 clocked at 50 MHz, which was 50% faster t |
https://en.wikipedia.org/wiki/Eradication%20of%20suffering | The eradication or abolition of suffering is the concept of using biotechnology to create a permanent absence of involuntary pain and suffering in all sentient beings.
Biology and medicine
The discovery of modern anesthesia in the 19th century was an early breakthrough in the elimination of pain during surgery, but acceptance was not universal. Some medical practitioners at the time believed that anesthesia was an artificial and harmful intervention in the body's natural response to injury. Opposition to anesthesia has since dissipated, however the prospect of eradicating pain raises similar concerns about interfering with life's natural functions.
People who are naturally incapable of feeling pain or unpleasant sensations due to rare conditions like pain asymbolia or congenital insensitivity to pain have been studied to discover the biological and genetic reasons for their pain-free lives. A Scottish woman with a previously unreported genetic mutation in a FAAH pseudogene (dubbed FAAH-OUT) with resultant elevated anandamide levels was reported in 2019 to be immune to anxiety, unable to experience fear, and insensitive to pain. The frequent burns and cuts she had due to her full hypoalgesia healed quicker than average.
In 1990, Medical Hypotheses published an article by L. S. Mancini on the "genetic engineering of a world without pain":
The development of gene editing techniques like CRISPR has raised the prospect that "scientists can identify the causes of certain unusual people's physical superpowers and use gene editing to grant them to others." Geneticist George Church has commented on the potential future of replacing pain with a painless sensory system:
Ethics and philosophy
Ethicists and philosophers in the schools of hedonism and utilitarianism, especially negative utilitarianism, have debated the merits of eradicating suffering. Transhumanist philosopher David Pearce, in The Hedonistic Imperative (1995), argues that the abolition of suffering is both |
https://en.wikipedia.org/wiki/Home%20Assistant | Home Assistant is free and open-source software for home automation designed to be a central control system for smart home devices with a focus on local control and privacy. It can be accessed through a web-based user interface, by using companion apps for Android and iOS, or by voice commands via a supported virtual assistant such as Google Assistant or Amazon Alexa.
After the Home Assistant software application is installed as a computer appliance, it will act as a central control system for home automation, commonly referred to as a smart home hub, that has the purpose of controlling IoT connectivity technology devices, software, applications and services which are supported by modular integration components, including native integration components for wireless communication protocols such as Bluetooth, Zigbee, and Z-Wave (used to create local personal area networks with small low-power digital radios). Home Assistant also supports controlling open and proprietary ecosystems if they provide public access via an Open API or MQTT for third-party integrations over the local area network or the Internet.
Information from all devices and their attributes (entities) that the Home Assistant software application sees can be used and controlled from within scripts trigger automation using scheduling and "blueprint" subroutines, e.g. for controlling lighting, climate, entertainment systems and home appliances.
History
The project was started as a Python application by Paulus Schoutsen in September 2013 and first published publicly on GitHub in November 2013.
In July 2017, a managed operating system called Hass.io was initially introduced to make it easier to use Home Assistant on single-board computers like the Raspberry Pi series. Its bundled "supervisor" management system allowed users to manage, backup, update the local installation and introduced the option to extend the functionality of the software with add-ons.
An optional subscription service was introduced |
https://en.wikipedia.org/wiki/Baubotanik | Baubotanik is a term that describes a building method in which architectural structures are created through the interaction of technical joints and plant growth. The term entails the practice of designing and building living structures using living plants. In this regard, living and non-living elements are intertwined in such a way that they grow together into plant-technical composite structures.
The Baubotanik method combines the aesthetic and ecological qualities of living trees with the static functions and structural requirements of buildings, thereby reducing the need for artificial building materials. The structures provide valuable habitats for a variety of animal species and make conventional foundations redundant, due to their root anchorage.
The use of Baubotanik is not a new invention and can be found in various historical and cultural contexts, such as the Tanzlinden (“dancing lime”) tree in Germany and living root bridge in North-East India. Common in the Indian state of Meghalaya and grown by the Khasi and Jaintia, the bridges consist of the aerial roots of rubber fig trees (Ficus elastica) and are grown over rivers to form walkable bridges. While the process can take fifteen years to complete, the bridges can be reinforced with natural materials and can withstand the strongest tropical storms. Furthermore, since the turn of the millennium, ‘willow churches’ (made of willow rods and lacking a fixed roof) have been constructed on various former garden show grounds, yet provide only limited functionality as buildings.
Research
An early publication in this field of study was the article Baubotanik: Mit lebenden Pflanzen konstruieren (translating to “Baubotanik: Designing with Living Plants) by Ferdinand Ludwig in 2005 in the magazine Baumeister. The term “Baubotanik” was defined in 2007 at the Institute of Theory of Architecture and Design (Institut für Grundlagen moderner Architektur und Entwerfen) at the University of Stuttgart, where its concept w |
https://en.wikipedia.org/wiki/XOS%20%28operating%20system%29 | XOS is an Android-based operating system developed by Hong Kong mobile phone manufacturer Infinix Mobile, a subsidiary of Transsion Holdings, exclusively for their smartphones.
XOS allows for a wide range of user customization without requiring rooting the mobile device. It was first introduced as XUI in 2015 and later as XOS in 2016. The operating system comes with utility applications that allow users to protect their privacy, improve speed, enhance experience among others. XOS comes with features like; XTheme, Scan to Recharge, Split Screen and XManager.
History
In 2015, Infinix Mobile released XUI 1.0, based on Android 5.0 "Lollipop", featuring XContacts, XTheme, XCloud and XShare. In July 2016, XOS 2.0 Chameleon was released based on Android 6.0 "Marshmallow", launching on HOT S and featuring XLauncher and fingerprint manager. An upgraded version XOS 2.2 Chameleon based on Android 7.0 "Nougat" was later launched in 2017 on Note 3 and Smart X5010. It features Scrollshot, Split Screen and Magazine Lockscreen.
In August 2017, XOS 3.0 Hummingbird was released based on Android 7.0 as also seen in XOS 2.2, launching on Zero 5, it later launched in 2018 on Hot S3 based on Android 8.0 "Oreo". An upgraded version XOS 3.2 Hummingbird based on Android 8.1 was later launched on Hot 6. It features Eye Care, Multi-Accounts and Device Tracking.
In May 2018, XOS 4.0 Honeybee was released based on Android 8.0, launching on Hot 7 and Zero 6, featuring Smart Screen Split, Notch Hiding, Scan To Recharge, Fingerprint Call Recording and Smart Text Classifier. An upgraded version XOS 4.1 Honeybee based on Android 8.1 was later launched on Hot 7 Pro.
In 2019, XOS 5.0 Cheetah was released based on Android 9.0 "Pie", launching on Hot S4 and Hot 8, featuring Privacy Protection, AI Intelligence, Smart Panel, Data Switcher and Fingerprint Reset Password. In December 2019, an upgraded version XOS 5.5 Cheetah based on Android 9.0 was released to Hot 8, featuring Game Assistant, Social T |
https://en.wikipedia.org/wiki/Gametophytic%20selection | Gametophytic selection is the selection of one haploid pollen grain over another through the means of pollen competition (see also certation), and that resulting sporophytic generations are positively affected by this competition. Evidence for the positive effects of gametophytic selection on the sporophyte generation has been observed in several flowering plant species, but there are is still some debate as to the biological significance of gametophytic selection.
Non-random success of pollen tubes
Pollen competition hypothesis
The competitive ability of pollen grains (microgapmetophytes) is rooted in the expression of their haploid genomes. The haploid genes are expressed immediately after pollen development and during pollen germination and pollen-tube growth. About 60% of genes expressed in the sporophyte are also expressed in the microgametophyte. This expression influences the ability of pollen tubes to compete during growth. When pollen competition occurs, the competitive ability is determined by differences between tube growth rate or the time it takes for germination to occur. Pollen completion is increased when pollen is not limiting and when pollen is in abundance relative to the number of ovules present in the ovary, but this does not guarantee pollen competition.
Non-random success of pollen
Studies on corn have observed a non-random success of pollen grains possessing different alleles resulting in ratios that differ than those expected by Mendel's Law of Segregation of Genes (certation). Pollen from a heterozygous sporophyte should exhibit an equal distribution of gametes inherited by offspring. Evidence of higher fertilization frequencies by pollen carrying one allele resulted in differences from expected random mating ratios.
Offspring quality
Evidence suggests that gametophytic selection may influence the fitness of seedlings in the next sporophytic generation. Studies on specific species have observed improvement of offspring quality sugge |
https://en.wikipedia.org/wiki/The%20Unimaginable%20Mathematics%20of%20Borges%27%20Library%20of%20Babel | The Unimaginable Mathematics of Borges' Library of Babel is a popular mathematics book on Jorge Luis Borges and mathematics. It describes several mathematical concepts related to the short story "The Library of Babel", by Jorge Luis Borges. Written by mathematics professor William Goldbloom Bloch, and published in 2008 by the Oxford University Press, it received an honorable mention in the 2008 PROSE Awards.
Topics
"The Library of Babel" was originally written by Borges in 1941,
based on an earlier essay he had published in 1939 while working as a librarian. It concerns a fictional library containing every possible book of a certain fixed length, over a 25-symbol alphabet (which, including spacing and punctuation, is sufficient for the Spanish language). These assumptions, based on the dimensions of his own library and spelled out in more detail in the story, imply that the total number of books in the library is 251312000, an enormous number. The story also describes, with an attitude of some horror, the physical layout of the library that holds all of these books, and some of the behavior of its inhabitants.
After a copy of "The Library of Babel" itself, as translated into English by Andrew Hurley, The Unimaginable Mathematics of Borges' Library of Babel has seven chapters on its mathematics. The first chapter, on combinatorics, repeats the calculation above, of the number of books in the library, putting it in context with the size of the known universe and with other huge numbers, and uses this material as an excuse to branch off into a discussion of logarithms and their use in estimation. The second chapter concerns a line in the story about the existence of a library catalog for the library, using information theory to prove that such a catalog would necessarily equal in size the library itself, and touching on topics including the prime number theorem. The third chapter considers the mathematics of the infinite, and the possibility of books with infinitely |
https://en.wikipedia.org/wiki/Guided%20filter | A guided filter is an edge-preserving smoothing image filter. As with a bilateral filter, it can filter out noise or texture while retaining sharp edges.
Comparison
Compared to the bilateral filter, the guided image filter has two advantages: bilateral filters have high computational complexity, while the guided image filter uses simpler calculations with linear computational complexity. Bilateral filters sometimes include unwanted gradient reversal artifacts and cause image distortion. The guided image filter is based on linear combination, making the output image consistent with the gradient direction of the guidance image, preventing gradient reversal.
Definition
One key assumption of the guided filter is that the relation between guidance and the filtering output is linear. Suppose that is a linear transformation of in a window centered at the pixel .
In order to determine the linear coefficient , constraints from the filtering input are required. The output is modeled as the input with unwanted components , such as noise/textures subtracted.
The basic model：
(1)
(2)
in which:
is the output pixel;
is the input pixel;
is the pixel of noise components;
is the guidance image pixel;
are some linear coefficients assumed to be constant in .
The reason to use a linear combination is that the boundary of an object is related to its gradient. The local linear model ensures that has an edge only if has an edge, since .
Subtract (1) and (2) to get formula (3)；At the same time, define a cost function (4)：
(3)
(4)
in which
is a regularization parameter penalizing large ;
is a window centered at the pixel .
And the cost function's solution is：
(5)
(6)
in which
and are the mean and variance of in ;
is the number of pixels in ;
is the mean of in .
After obtaining the linear coefficients , the filtering output is provided by the following algorithm:
Algorithm
By definition, the algorithm can be written as:
|
https://en.wikipedia.org/wiki/Tellonym | Tellonym (from English "to tell" and German "anonym") is a cross-platform messaging app to have questions answered. Tellonym was created as a means to give and receive anonymous feedback. Developed by German software company Callosum Software, the app's userbase is predominantly German.
History
Comparable projects were started with ask.fm in 2010, while the competitor Sarahah from Saudi Arabia also started in 2016. The Tellonym project started in April 2016. 700,000 users registered in May 2017. By June 2018, 2 million users had registered. , the Google App Store indicates more than 10 million registrations. According to the surveys of the Youth Internet Monitor 2018 in Austria, 12 percent of 11 to 17-year-olds use the App.
Technology
Tells are what they call the messages on Tellonym. A user's profile consists of a username, a short description, and an emoji, which can be obtained at events or purchased. The profile is used to gather feedback about oneself, work, and any other questions. As a result, Tellonym can be used as a survey tool. Complete strangers, in addition to friends, can access the personal profile via a public link and leave comments. This facilitates the posting of hurtful or annoying comments. It is not necessary to have your own profile, where you would have to provide your name or e-mail address, in order to rate other users.
Callosum Software retains messages and end-device IP addresses for possible transmission to criminal authorities. The app lets you create a user-based word filter with a maximum of ten words that prevents "tells" containing the listed words from reaching the user. In practice, this word filter is ineffective because it can be bypassed by exchanging single letters. A timer function can be used to schedule when the message will be sent.
Cyber-bullying threats
Because users can create tells anonymously, it is easier for them to insult or harass others, which can lead to cyberbullying. Tellonym frequently contains "drasti |
https://en.wikipedia.org/wiki/Charge-pump%20phase-locked%20loop | Charge-pump phase-locked loop (CP-PLL) is a modification of phase-locked loops with
phase-frequency detector and square waveform signals. CP-PLL allows for a quick lock of the phase of the incoming signal, achieving low steady state phase error.
Phase-frequency detector (PFD)
Phase-frequency detector (PFD) is triggered by the trailing edges of the reference (Ref) and controlled (VCO) signals.
The output signal of PFD can have only three states: 0, , and .
A trailing edge of the reference signal forces the PFD to switch to a higher state,
unless it is already in the state .
A trailing edge of the VCO signal forces the PFD to switch to a lower state,
unless it is already in the state .
If both trailing edges happen at the same time, then the PFD switches to zero.
Mathematical models of CP-PLL
A first linear mathematical model of second-order CP-PLL was suggested by F. Gardner in 1980. A nonlinear model without the VCO overload was suggested by M. van Paemel in 1994
and then refined by N. Kuznetsov et al. in 2019. The closed form mathematical model of CP-PLL taking into account the VCO overload is derived in.
These mathematical models of CP-PLL allow to get analytical estimations of the hold-in range
(a maximum range of the input signal period
such that there exists a locked state at which the VCO is not overloaded)
and the pull-in range (a maximum range of the input signal period
within the hold-in range such that for any initial state the CP-PLL
acquires a locked state).
Continuous time linear model of the second order CP-PLL and Gardner's conjecture
Gardner's analysis is based on the following approximation: time interval on which PFD has non-zero state on each period of reference signal is
Then averaged output of charge-pump PFD is
with corresponding transfer function
Using filter transfer function and VCO transfer function one gets Gardner's linear approximated average model of second-order CP-PLL
In 1980, F. Gardner, based on the above reas |
https://en.wikipedia.org/wiki/Kane%20S.%20Yee | Kane Shee-Gong Yee (born March 26, 1934) is a Chinese-American electrical engineer and mathematician. He is best known for introducing the finite-difference time-domain method (FDTD) in 1966.
His research interests include numerical electromagnetics, fluid dynamics, continuum mechanics and numerical analysis of partial differential equations.
Biography
Yee was born on March 26, 1934, in Guangzhou, Republic of China. He received his B.S. and M.S. in electrical engineering from University of California, Berkeley in 1957 and 1958, respectively. He has completed his PhD in applied mathematics department at the same university under the supervision of Bernard Friedman in 1963; his dissertation involved the study of boundary value problems for Maxwell's equations. From 1959 to 1961, he was employed at Lockheed Missiles and Space Company, researching diffraction in electromagnetic waves.
In 1966, Yee published a paper on the use of a finite difference staggered grids algorithm in the solution of Maxwell's equations. Yee was initially motivated by his self-studies in Fortran to develop the method. Appearing on IEEE Transactions on Antennas and Propagation, the article received little attention at the time of its release. The incorrect numerical stability conditions on Yee's paper were corrected by Dong-Hoa Lam in 1969 and Allen Taflove and Morris E. Brodwin in 1975. The method was subsequently renamed as finite-difference time-domain method in 1980. FDTD is also referred as Yee algorithm, with its specific discretized grid being known as Yee lattice or Yee cell.
Between 1966 and 1984, Yee became a professor of electrical engineering and mathematics at the University of Florida and later at Kansas State University. He became a consultant to Lawrence Livermore National Laboratory in 1966, working on microwave vulnerability problems at the same institute from 1984 to 1987. In 1987, he became a research scientist at Lockheed Palo Alto Research Lab, working on computationa |
https://en.wikipedia.org/wiki/Combinatorics%20of%20Experimental%20Design | Combinatorics of Experimental Design is a textbook on the design of experiments, a subject that connects applications in statistics to the theory of combinatorial mathematics. It was written by mathematician Anne Penfold Street and her daughter, statistician Deborah Street, and published in 1987 by the Oxford University Press under their Clarendon Press imprint.
Topics
The book has 15 chapters. Its introductory chapter covers the history and applications of experimental designs, it has five chapters on balanced incomplete block designs and their existence, and three on Latin squares and mutually orthogonal Latin squares. Other chapters cover resolvable block designs, finite geometry, symmetric and asymmetric factorial designs, and partially balanced incomplete block designs.
After this standard material, the remaining two chapters cover less-standard material. The penultimate chapter covers miscellaneous types of designs including circular block designs, incomplete Latin squares, and serially balanced sequences. The final chapter describes specialized designs for agricultural applications. The coverage of the topics in the book includes examples, clearly written proofs, historical references, and exercises for students.
Audience and reception
Although intended as an advanced undergraduate textbook, this book can also be used as a graduate text, or as a reference for researchers. Its main prerequisites are some knowledge of linear algebra and linear models, but some topics touch on abstract algebra and number theory as well.
Although disappointed by the omission of some topics, reviewer D. V. Chopra writes that the book "succeeds remarkably well" in connecting the separate worlds of combinatorics and statistics.
And Marshall Hall, reviewing the book, called it "very readable" and "very satisfying".
Related books
Other books on the combinatorics of experimental design include Statistical Design and Analysis of Experiments (John, 1971), Constructions and Combinat |
https://en.wikipedia.org/wiki/Five-bar%20linkage | In kinematics, a five-bar linkage is a mechanism with two degrees of freedom that is constructed from five links that are connected together in a closed chain. All links are connected to each other by five joints in series forming a loop. One of the links is the ground or base. This configuration is also called a pantograph, however, it is not to be confused with the parallelogram-copying linkage pantograph.
The linkage can be a one-degree-of-freedom mechanism if two gears are attached to two links and are meshed together, forming a geared five-bar mechanism.
Robotic configuration
When controlled motors actuate the linkage, the whole system (a mechanism and its actuators) becomes a robot. This is usually done by placing two servomotors (to control the two degrees of freedom) at the joints A and B, controlling the angle of the links L2 and L5. L1 is the grounded link. In this configuration, the controlled endpoint or end-effector is the point D, where the objective is to control its x and y coordinates in the plane in which the linkage resides. The angles theta 1 and theta 2 can be calculated as a function of the x,y coordinates of point D using trigonometric functions. This robotic configuration is a parallel manipulator. It is a parallel configuration robot as it is composed of two controlled serial manipulators connected to the endpoint.
Unlike a serial manipulator, this configuration has the advantage of having both motors grounded at the base link. As the motor can be quite massive, this significantly decreases the total moment of inertia of the linkage and improves backdrivability for haptic feedback applications. On the other hand, workspace reached by the endpoint is usually significantly smaller than that of a serial manipulator.
Kinematics and dynamics
Both the forward and inverse kinematics of this robotic configuration can be found in closed-form equations through geometric relationships. Different methods of finding both have been done by Campion and |
https://en.wikipedia.org/wiki/Synd%20iNNOVATE | Synd iNNOVATE 2019 was the National Level Hackathon conducted by Syndicate Bank in September 2019 to encourage Innovation in Banking Industry. It attracted more than 3,500 ideas from applicants from all over India out of which final 40 teams were called for Onsite Hackathon.
Themes
Synd iNNOVATE 2019 had thirteen themes to participate, which are as follows:
Open Innovation
Customer Social Profiling
Voice Based Customer Grievance redressal System
An App for Agents(Referral Marketing & Affiliate Marketing)
Branch wise customer ranking for the use of Digital Banking Channels & Rewards Mechanism for the same
A centralized system for checking Branch Ambience & Cleanliness
WhatsApp Business integration for amazing customer experience.
Automated Queue Management System for Branch.
Developing automated system for Identification & Triggering alert when a High Net Worth customer visits the Branch and/or using our Digital Platform like Internet/Mobile Banking etc.
Mobile number verification of customers through QR scan, Missed Call or any other easy procedure
Design of UX/UI for LAPS
Early Fraud Detection Mechanism
Customer Acquisition
Synd iNNOVATE received more than 3500 Ideas in all the themes combined. Then 400 teams were shortlisted to participate in 2nd round for submission of online prototype, out of these 400 prototypes, 40 were selected for final onsite Hackathon in Bengaluru.
Hackathon Schedule & Management
Synd iNNOVATE was managed by Bhanu Srivastav from Syndicate Bank. who was working in Business Process Re-Engineering & Innovation Department in Syndicate Bank Corporate Office. The event was managed by Hackerearth.
The Hackathon was scheduled in 3 phases:
Phase 1 Idea Submission (Online)
Phase 2 Prototype submission (Online)
Phase 3 Onsite Hackathon (Offline)
The prize money for the winners was:
1st Prize - Rs 3,00,000/-
2nd Prize - Rs 2,00,000/-
3rd Prize - Rs 1,00,000/-
10 Consolation Prizes - 10,000/-
Reception
The final event was |
https://en.wikipedia.org/wiki/William%20F.%20Egan | William F. Egan (1936 – December 216, 2012) was well-known expert and author in the area of PLLs. The first and second editions of his book
Frequency Synthesis by Phase Lock
as well as his book Phase-Lock Basics
are references among electrical engineers specializing in areas involving PLLs.
Egan's conjecture on the pull-in range of type II APLL
In 1981, describing the high-order PLL, William Egan conjectured that type II APLL has theoretically infinite the hold-in and pull-in ranges. From a mathematical point of view, that means that the loss of global stability in type II APLL is caused by the birth of self-excited oscillations and not hidden oscillations (i.e., the boundary of global stability and the pull-in range in the space of parameters is trivial).
The conjecture can be found in various later publications, see e.g. and for type II CP-PLL. The hold-in and pull-in ranges of type II APLL for a given parameters may be either (theoretically) infinite or empty, thus, since the pull-in range is a subrange of the hold-in range, the question is whether the infinite hold-in range implies infinite pull-in range (the Egan problem).
Although it is known that for the second-order type II APLL the conjecture is valid, the work by Kuznetsov et al.
shows that the Egan conjecture may be not valid in some cases.
A similar statement for the second-order APLL with lead-lag filter is known as Kapranov's conjecture on the pull-in range of type I APLL.
In general, his conjecture is not valid and the global stability and the pull-in range for the type I APLL with lead-lag filters may be limited by the birth of hidden oscillations (hidden boundary of the global stability and the pull-in range).
For control systems, a similar conjecture was formulated by R. Kalman in 1957 (see Kalman's conjecture).
References
1936 births
2012 deaths
American electrical engineers
Hidden oscillation |
https://en.wikipedia.org/wiki/Thousands%20of%20Problems%20for%20Theorem%20Provers | TPTP (Thousands of Problems for Theorem Provers) is a freely available collection of problems for automated theorem proving. It is used to evaluate the efficacy of automated reasoning algorithms. Problems are expressed in a simple text-based format for first order logic or higher-order logic. TPTP is used as the source of some problems in CASC.
References
External links
Web site.
Automated theorem proving |
https://en.wikipedia.org/wiki/Sooraj%20Surendran | Sooraj Surendran is an Indian technologist and electronic engineering graduate from Anna University. He has made significant contributions to motorized wheelchair deployment in Tamil Nadu.
Early life and education
Surendran was born in Kollam, Kerala, India. His mother Sudha was a housewife and his father was K Surendran Pillai.
He completed schooling in Sree Buddha, a Central Board of Secondary Education school in Karunagappalli, Kerala. He earned his degree from Anna University in electronic engineering.
Career
Surendran graduated from Anna University with a BTech in electronic engineering in 2011. He worked on motorized wheelchair design and nursing care bed electronic unit design, and developed an electronic system for nursing care beds that integrated Bluetooth technology to control the functions of a nursing care bed via an Android application. Surendran was invited to help develop electronic control units for lightweight motorized wheelchairs as a part of a Tamil Nadu program to distribute motorized wheelchairs to 2,000 people.
References
External links
Electronic engineering
1990 births
Living people
People from Kollam |
https://en.wikipedia.org/wiki/Chat%20fiction | Chat fiction is a format of web fiction written solely in the form of text-message or instant messaging conversations. Works are read primarily through dedicated mobile phone applications, the earliest being Hooked, which launched in 2015. The format became popular among teenagers and young adults, and other competing platforms followed, including Yarn and Tap, among others.
History
The first chat fiction platform, Hooked, was created by Prerna Gupta and Parag Chordia, who were writing a novel and decided to do A/B testing to gauge reader preferences. They found that most of their target audience of teenagers failed to finish 1,000-word excerpts of best-selling young-adult novels, but read through stories of the same length written as text message conversations. They accordingly developed and launched Hook in 2015. The app gained popularity from late 2016, and reached the Apple App Store's top position among free apps in 2017. Competing apps began launching the same year, including Yarn, which also has a focus on interactive fiction, and Tap, developed by the online publishing platform Wattpad.
Format
Chat fiction stories are presented as digital text conversations between two or more characters, without any narration. The format limits possible storytelling options, and presents a challenge to authors in conveying narrative only through dialogue. Most popular stories are of the horror and thriller genres. The format has been popular among teenagers and young adults, though it has been criticized as not providing a meaningful reading experience.
Applications usually present the story incrementally, with the user tapping to advance the story message by message. Some platforms feature content by paid writers, while others allow or rely on user contributions. Revenue is usually based on a freemium model, with basic access being free while subscribing offers removal of limits and other benefits.
References
Web fiction
Fiction forms
Interactive fiction
Interactive n |
https://en.wikipedia.org/wiki/Ocean%20Biodiversity%20Information%20System | The Ocean Biodiversity Information System (OBIS), formerly Ocean Biogeographic Information System, is a web-based access point to information about the distribution and abundance of living species in the ocean. It was developed as the information management component of the ten year Census of Marine Life (CoML) (2001-2010), but is not limited to CoML-derived data, and aims to provide an integrated view of all marine biodiversity data that may be made available to it on an open access basis by respective data custodians. According to its web site as at July 2018, OBIS "is a global open-access data and information clearing-house on marine biodiversity for science, conservation and sustainable development." 8 specific objectives are listed in the OBIS site, of which the leading item is to "Provide [the] world's largest scientific knowledge base on the diversity, distribution and abundance of all marine organisms in an integrated and standardized format".
History and current status
Initial ideas for OBIS were developed at a CoML meeting on benthic (bottom-dwelling) ocean life in October 1997. Recommendations from this workshop led to a web site (http://marine.rutgers.edu/OBIS) at Rutgers in 1998 to demonstrate the initial OBIS concept. An inaugural OBIS International Workshop was held on November 3–4, 1999 in Washington, DC, which led to scoping of the project and outreach to potential partners, with selected contributions published in a special issue of Oceanography magazine, within which OBIS founder Dr. J. F. Grassle articulated the vision of OBIS as "an on-line, worldwide atlas for accessing, modeling and mapping marine biological data in a multidimensional geographic context." In May 2000, US Government Agencies in the National Oceanographic Partnership Program together with the Alfred P. Sloan Foundation funded eight research projects to initiate OBIS. In May 2001, the US National Science Foundation funded Rutgers University to develop a global portal for OBIS. A |
https://en.wikipedia.org/wiki/Order%20convergence | In mathematics, specifically in order theory and functional analysis, a filter in an order complete vector lattice is order convergent if it contains an order bounded subset (that is, is contained in an interval of the form ) and if
where is the set of all order bounded subsets of X, in which case this common value is called the order limit of in
Order convergence plays an important role in the theory of vector lattices because the definition of order convergence does not depend on any topology.
Definition
A net in a vector lattice is said to decrease to if implies and in
A net in a vector lattice is said to order-converge to if there is a net in that decreases to and satisfies for all .
Order continuity
A linear map between vector lattices is said to be order continuous if whenever is a net in that order-converges to in then the net order-converges to in
is said to be sequentially order continuous if whenever is a sequence in that order-converges to in then the sequence order-converges to in
Related results
In an order complete vector lattice whose order is regular, is of minimal type if and only if every order convergent filter in converges when is endowed with the order topology.
See also
References
Functional analysis
Order theory |
https://en.wikipedia.org/wiki/Multi-cycle%20processor | A multi-cycle processor is a processor that carries out one instruction over multiple clock cycles, often without starting up a new instruction in that time (as opposed to a pipelined processor).
See also
Single-cycle processor, a processor executing (and finishing) one instruction per clock cycle
References
Microprocessors |
https://en.wikipedia.org/wiki/Hack%20Club | Hack Club is a global nonprofit network of high school computer hackers, makers and coders founded in 2014 by Zach Latta. It now includes more than 400 high school clubs and 28,000 students. It has been featured on the TODAY Show, and profiled in the Wall Street Journal and many other publications.
Programs
Hack Club's primary focus is its clubs program, in which it supports high school coding clubs through learning resources and mentorship. It also runs a series of other programs and events, both former and current.
A few notable programs and events are:
HCB - a fiscal sponsorship program originally targeted at high school hacker events
AMAs - video calls with industry experts such as Elon Musk and Vitalik Buterin
Summer of Making - a collaboration with GitHub, Adafruit & Arduino to create an online summer program for teenagers during the COVID-19 pandemic that included $50k in hardware donations to teen hackers around the world
The Hacker Zephyr - a cross-country hackathon on a train across America.
Assemble - the first high school hackathon in San Francisco since the pandemic, with the stated goal of "kick[ing] off a hackathon renaissance"
Epoch - A global high schooler-led hackathon in Delhi NCR organised in public to inspire the community of student hackers and bring hundreds of teenagers together
Winter Hardware Wonderland - An online winter program where teenagers submit ideas for hardware projects and, if accepted, get grants of up to $250
Outernet - An in-person hackathon took place in the Northeast Kingdom for 4 day straight
Haunted House - An hackathon celebrate in Halloween 2023, with many satellite events all over the world
Funding
Hack Club is funded by grants from philanthropic organizations and donations from individual supporters. In 2019, GitHub Education provided cash grants of up to $500 to every Hack Club "hackathon" event. In May 2020, GitHub committed to a $50K hardware fund, globally alongside Arduino and Adafruit, to delive |
https://en.wikipedia.org/wiki/Chisel%20%28programming%20language%29 | The Constructing Hardware in a Scala Embedded Language (Chisel)
is an open-source hardware description language (HDL) used to describe digital electronics and circuits at the register-transfer level. Chisel is based on Scala as an embedded domain-specific language (DSL). Chisel inherits the object-oriented and functional programming aspects of Scala for describing digital hardware. Using Scala as a basis allows describing circuit generators. High quality, free access documentation exists in several languages.
Circuits described in Chisel can be converted to a description in Verilog for synthesis and simulation.
Code examples
A simple example describing an adder circuit and showing the organization of components in Module with input and output ports:
class Add extends Module {
val io = IO(new Bundle {
val a = Input(UInt(8.W))
val b = Input(UInt(8.W))
val y = Output(UInt(8.W))
})
io.y := io.a + io.b
}
A 32-bit register with a reset value of 0:
val reg = RegInit(0.U(32.W))
A multiplexer is part of the Chisel library:
val result = Mux(sel, a, b)
Use
Although Chisel is not yet a mainstream hardware description language, it has been explored by several companies and institutions. The most prominent use of Chisel is an implementation of the RISC-V instruction set, the open-source Rocket chip.
Chisel is mentioned by the Defense Advanced Research Projects Agency (DARPA) as a technology to improve the efficiency of electronic design, where smaller design teams do larger designs.
Google has used Chisel to develop a Tensor Processing Unit for edge computing. Some developers prefer Chisel as it requires 5 times lesser code and is much faster to develop than Verilog.
Circuits described in Chisel can be converted to a description in Verilog for synthesis and simulation using a program named FIRRTL.
See also
VHDL
Verilog
SystemC
SystemVerilog
References
External links
University of California, Berkeley
Hardware description languages
Science and |
https://en.wikipedia.org/wiki/43%2C112%2C609 | 43,112,609 (forty-three million, one hundred twelve thousand, six hundred nine) is the natural number following 43,112,608 and preceding 43,112,610.
In mathematics
43,112,609 is a prime number. Moreover, it is the exponent of the 47th Mersenne prime, equal to M43,112,609 = 243,112,609 − 1, a prime number with 12,978,189 decimal digits. It was discovered on August 23, 2008 by Edson Smith, a volunteer of the Great Internet Mersenne Prime Search. The 45th Mersenne prime, M37,156,667 = 237,156,667 − 1, was discovered two weeks later on September 6, 2008, marking the shortest chronological gap between discoveries of Mersenne primes since the formation of the online collaborative project in 1996. It was the first time since 1963 when two Mersenne primes were discovered less than 30 days apart from each other. Less than a year later, on June 4, 2009, the 46th Mersenne prime, M42,643,801 = 242,643,801 − 1, was discovered by Odd Magnar Strindmo, a GIMPS participant from Norway. The result for this prime was first reported to the server in April 2009, but due to a bug, remained unnoticed for nearly two months. Having 12,837,064 decimal digits, it is only 141,125 digits, or 1.09%, shorter than M43,112,609. These two Mersenne primes hold the record for the ones with the smallest ratio between their exponents.
43,112,609 is the degree of four of the seven largest primitive binary trinomials over GF(2) found in 2016. and were the four largest in 2011.
43,112,609 is a Sophie Germain prime, the largest of only eight known Mersenne prime indexes to have this property.
43,112,609 is not a Gaussian prime, the largest of only 28 known Mersenne prime indexes to have this property.
References
Further reading
George Woltman, Scott Kurowski, On the discovery of the 45th and 46th known Mersenne primes", Fibonacci Quarterly, vol. 46/47, no. 3, pp. 194–197, August 2008.
Integers
Prime numbers |
https://en.wikipedia.org/wiki/The%20First%20TV | The First, also called The First TV and stylized as The F1rst, is a conservative opinion and commentary network in the United States started in October 2019. It has five hosts; including Bill O'Reilly.
History
The First was launched in October 2019 on Pluto TV, a streaming platform owned by Paramount Global. It was started in partnership with Red Seat Ventures. It offers about 45 hours of original programming a week. In January 2023, The First was added to DirecTV, after it concurrently dropped Newsmax TV due to demands for carriage fees.
Hosts
The First launched with two hosts in October 2019, former combat veteran Jesse Kelly and former CIA analyst Buck Sexton. In January 2020, the network added California-based talk radio host Mike Slater and conservative female talk radio host Dana Loesch. On June 1, 2020, the network announced that Bill O'Reilly was joining the network with his show No Spin News. He began the online show in 2017 after being fired from Fox News Channel, in the wake of The New York Times publishing details of six sexual misconduct lawsuits O'Reilly had settled. Former OANN host, CPAC speaker, and conservative podcaster Liz Wheeler was added to the network in January of 2023.
Reception
Tyler Hersko of IndieWire criticized ViacomCBS for their involvement in O'Reilly's show, commenting that its Pluto TV debut coincided with the date that its entertainment and youth channels were made unavailable for eight minutes 46 seconds in solidarity with Black Lives Matter. Hersko found this hypocritical in light of comments made by O'Reilly about African-Americans. A petition by ViacomCBS employees urged the company to remove The First for similar reasons.
References
External links
Official website
Conservative media in the United States
2019 establishments in the United States
Bill O'Reilly (political commentator)
Streaming media systems |
https://en.wikipedia.org/wiki/Axo-axonic%20synapse | An axo-axonic synapse is a type of synapse, formed by one neuron projecting its axon terminals onto another neuron's axon.
Axo-axonic synapses have been found and described more recently than the other more familiar types of synapses, such as axo-dendritic synapses and axo-somatic synapses. The spatio-temporal properties of neurons get altered by the type of synapse formed between neurons. Unlike the other types, the axo-axonic synapse does not contribute towards triggering an action potential in the postsynaptic neuron. Instead, it affects the probability of neurotransmitter release in the response to any action potential passing through the axon of the postsynaptic neuron. Thus, axo-axonic synapses appear to be very important for the brain in achieving a specialized neural computation.
Axo-axonic synapses are found throughout the central nervous system, including in the hippocampus, cerebral cortex and striatum in mammals; in the neuro-muscular junctions in crustaceans; and in the visual circuitry in dipterans. Axo-axonic synapses can induce either inhibitory or excitatory effects in the postsynaptic neuron. A classic example of the role of axo-axonic synapses is causing inhibitory effects on motoneurons in the spinal-somatic reflex arc. This phenomenon is known as presynaptic-inhibition.
Background
Complex interconnections of neurons form neural networks, which are responsible for various types of computation in the brain. Neurons receive inputs mainly through dendrites, which play a role in spatio-temporal computation, leading to the firing of an action potential which subsequently travels to synaptic terminals passing through axons. Based on their locations, synapses can be classified into various kinds, such as axo-dendritic synapse, axo-somatic synapse, and axo-axonal synapse. The prefix here indicates the part of the presynaptic neuron (i.e., ‘axo-’ for axons), and the suffix represents the location where the synapse is formed on the postsynaptic neuron |
https://en.wikipedia.org/wiki/Bionomia | Bionomia (formerly Bloodhound Tracker) is a database and database entry tool which permits the name strings of collectors, and of taxonomists who determine specimen data, to be assigned to the unique person who collected or identified the specimen. If the person is living, this is done via their ORCID iD, and if dead, via their Wikidata identifier. It thereby resolves ambiguity where two or more collectors have similar names; or where one collector has worked under two names, or a single name written in two or more ways. The specimen data associated with, and used by, Bionomia are the aggregated GBIF data.
This mechanism of contributing to specimen data arose from a project initiated by the Muséum national d’histoire naturelle, Paris (MNHN) in March 2019, and is motivated (in part) by "the world-wide importance of natural history collections, (which) are at risk because they are critically underfunded or undervalued. A contributing factor for this apparent neglect is the lack of a professional reward system that quantifies and illustrates the breadth and depth of expertise required to collect and identify specimens, maintain them, digitize their labels, mobilize the data, and enhance these data as errors and omissions are identified by stakeholders." It is also motivated by the fact that the important work of taxonomists in identifying specimens in collections across the world fails to be recognised, and this failure, fails both institutions and taxonomists. In August 2018, Bionomia was launched (under the name Bloodhound Tracker) as a submission to the Ebbe Nielsen Challenge.
Other papers which set the scene, the rationale and the purpose of Bionomia are:
The primary task in Bionomia is to resolve the name strings of the various collectors and the taxonomists who have determined the species of a specimen into unique human beings. This having been done, the records of plant and animal specimens contained in GBIF downloads (permanently referenced by DOIs), tog |
https://en.wikipedia.org/wiki/Roger%20F.%20Harrington | Roger Fuller Harrington (born December 24, 1925) is an American electrical engineer and professor emeritus at Syracuse University. He is best known for his contributions to computational electromagnetics with his development of method of moments (MoM). Harrington's 1968 book, Field Computation by Moment Methods, is regarded as a pivotal textbook on the subject.
Biography
Harrington was born on December 24, 1925, in Buffalo, New York. He started majoring in electrical engineering in 1943 at Syracuse University; his studies were interrupted in the following year by World War II. During this time, he served as an instructor under the Electronics Training Program at the U.S. Naval Radio Materiel School in Dearborn, Michigan, while working as an electronics technician. He completed his studies after the war, receiving B.S. and M.S. degrees in 1948 and 1950, respectively. Briefly remaining at Syracuse University as a research assistant and instructor, he started his doctoral studies under Victor H. Rumsey at Ohio State University, receiving his PhD in 1952.
Harrington returned to Syracuse University following his doctoral studies, working there as a professor until his retirement in 1994. Following his retirement, he briefly worked as a visiting professor at University of Arizona. During his tenure at Syracuse University, he has worked on research projects for the U.S. Army Signal Corps, Office of Naval Research, General Electric and the U.S. Air Force Office of Scientific Research. He has also held visiting professorship positions at University of Illinois in between 1959 and 1960, University of California, Berkeley in 1964 and the Technical University of Denmark in 1969.
Harrington is a recipient of IEEE Centennial Medal, IEEE Antennas and Propagation Society Distinguished Achievement Award and IEEE Electromagnetics Award in 1984, 1989 and 2000, respectively. In 2014, he was awarded the Benjamin Franklin Medal in electrical engineering for his contributions to the s |
https://en.wikipedia.org/wiki/Minimum%20evolution | Minimum evolution is a distance method employed in phylogenetics modeling. It shares with maximum parsimony the aspect of searching for the phylogeny that has the shortest total sum of branch lengths.
The theoretical foundations of the minimum evolution (ME) criterion lay in the seminal works of both Kidd and Sgaramella-Zonta and Rzhetsky and Nei. In these frameworks, the molecular sequences from taxa are replaced by a set of measures of their dissimilarity (i.e., the so called "evolutionary distances") and a fundamental result states that if such distances were unbiased estimates of the true evolutionary distances from taxa (i.e., the distances that one would obtain if all the molecular data from taxa were available), then the true phylogeny of taxa would have an expected length shorter than any other possible phylogeny T compatible with those distances.
Relationships and differences with maximum parsimony
It is worth noting here a subtle difference between the maximum-parsimony criterion and the ME criterion: while maximum-parsimony is based on an abductive heuristic, i.e., the plausibility of the simplest evolutionary hypothesis of taxa with respect to the more complex ones, the ME criterion is based on Kidd and Sgaramella-Zonta's conjectures that were proven true 22 years later by Rzhetsky and Nei. These mathematical results set the ME criterion free from the Occam's razor principle and confer it a solid theoretical and quantitative basis.
Statistical consistency
The ME criterion is known to be statistically consistent whenever the branch lengths are estimated via the Ordinary Least-Squares (OLS) or via linear programming.
However, as observed in Rzhetsky & Nei's article, the phylogeny having the minimum length under the OLS branch length estimation model may be characterized, in some circumstance, by negative branch lengths, which unfortunately are empty of biological meaning.
To solve this drawback, Pauplin proposed to replace OLS with a new particul |
https://en.wikipedia.org/wiki/ViaGen%20Pets | ViaGen Pets, based in Cedar Park, Texas, is a division of TransOva Genetics, that offers animal cloning services to pet owners. ViaGen Pets division was launched in 2016.
ViaGen Pets offers cloning as well as DNA preservation services, sometimes called tissue or cell banking.
Technology and patents
ViaGen's subsidiary, Start Licensing, owns a cloning patent which is licensed to their only competitor as of 2018, who also offers animal cloning services.
The cloning process used by both ViaGen and their competitor is somatic cell nuclear transfer, the same as which was used for cloning Dolly the Sheep.
History
ViaGen Pets began by offering cloning to the livestock and equine industry in 2003, and later included cloning of cats and dogs in 2016.
References
Cloning
Companies based in Texas
Companies based in Cedar Park, Texas
American companies established in 2016
Biotechnology companies of the United States
External links
official website |
https://en.wikipedia.org/wiki/Decentraleyes | Decentraleyes is a free and open-source browser extension used for local content delivery network (CDN) emulation. Its primary task is to block connections to major CDNs such as Cloudflare and Google (for privacy and anti-tracking purposes) and serve popular web libraries (such as JQuery and AngularJS) locally on the user's machine. Decentraleyes is available for Microsoft Edge, Mozilla Firefox + Firefox ESR, Google Chrome, Pale Moon and Opera web browsers.
Overview
Decentraleyes is bundled with 14 Javascript libraries; AngularJS, Backbone.js, Dojo, Ember.js, Ext Core, jQuery, jQuery UI, Modernizr, MooTools, Prototype (including script.aculo.us), SWFObject, Underscore.js, and Web Font Loader. It can locally redirect connections to the Google Hosted Libraries, Microsoft Ajax CDN, CDNJS (Cloudflare), jQuery CDN (MaxCDN), jsDelivr (MaxCDN), Yandex CDN, Baidu CDN, Sina Public Resources, and UpYun Libraries networks. With these bundled resources in the software package, they are served to the user locally from their machine, as opposed to from a server. The blocking of connections to these CDNs is claimed to result in faster loading times for the end user.
Reception
Lifehacker has recommended Decentraleyes as a solution to help prevent the user's data from being tracked by Google. CloudPro, a UK-based cloud computing publication, endorsed Decentraleyes as a way of blocking malicious man-in-the-middle CDN attacks.
History
Decentraleyes was first released in late 2015, compatible with the Firefox browser.
Between 2016 and 2017, a spinoff extension called LocalCDN was created. It brought the functionality of Decentraleyes to Chromium based browsers, for which it was not available at the time (until later that year).
In October 2017, Decentraleyes 2.0.0 was released. The new version was rewritten from scratch to comply with the new Firefox browser add-on standards and had a more consistent user interface and better support for right-to-left languages.
References
Exter |
https://en.wikipedia.org/wiki/Autogamy%20depression | Autogamy depression can be defined as the "lowered viability of autogamous progeny relative to geitonogamous progeny”. Viability has also been evaluated in terms of percent fruit set or seed set rather than reproductive fitness of the progeny. The experimental design for observing the occurrence of autogamy depression is called an "autogamy depression test" which has been described by researchers as analogous to a test for inbreeding depression. The ability for fitness of autogamous progeny to differ from geitonogamous progeny comes from the understanding that plants can accumulate heritable mutational variation through both mitotic division and meiotic division. Because plants have indeterminate growth, the apical meristems that contribute to the development of the reproductive structures of a plant have the potential to undergo continual mitosis resulting in the accumulation of somatic mutations (acquired mutations). It has been demonstrated through research that long lived plants can have higher per generation mutation rate (based on occurrences of more mitotic cell divisions compared to short lived plants). Any deleterious mutations that appear during mitotic growth are filtered out through cell lineage selection, in which deleterious mutations that are subject to developmental selection during mitotic growth are replaced by vigorous cell lineages, however, somatic mutations that are not expressed will not be subject to selection during growth of the plant and will accumulate in the apical meristem.
Phenotypic effects of somatic mutations
There is evidence of the phenotypic effects of somatic mutations in increased Chlorophyll mutants of some long-lived plants. Chlorophyll mutants are inherently easy to observe because of the phenotypic effects of the chlorophyll mutations. Because of the highly conserved nature of photosynthetic processes, these chlorophyll mutation rates can be generalized to most angiosperms. Somatic mutations accumulating during vegetativ |
https://en.wikipedia.org/wiki/Higuchi%20dimension | In fractal geometry, the Higuchi dimension (or Higuchi fractal dimension (HFD)) is an approximate value for the box-counting dimension of the graph of a real-valued function or time series. This value is obtained via an algorithmic approximation so one also talks about the Higuchi method. It has many applications in science and engineering and has been applied to subjects like characterizing primary waves in seismograms, clinical neurophysiology and analyzing changes in the electroencephalogram in Alzheimer’s disease.
Formulation of the method
The original formulation of the method is due to T. Higuchi. Given a time series consisting of data points and a parameter the Higuchi Fractal dimension (HFD) of is calculated in the following way: For each and define the length by
The length is defined by the average value of the lengths ,
The slope of the best-fitting linear function through the data points is defined to be the Higuchi fractal dimension of the time-series .
Application to functions
For a real-valued function one can partition the unit interval into equidistantly intervals and apply the Higuchi algorithm to the times series . This results into the Higuchi fractal dimension of the function . It was shown that in this case the Higuchi method yields an approximation for the box-counting dimension of the graph of as it follows a geometrical approach (see Liehr & Massopust 2020).
Robustness and stability
Applications to fractional Brownian functions and the Weierstrass function reveal that the Higuchi fractal dimension can be close to the box-dimension. On the other hand, the method can be unstable in the case where the data are periodic or if subsets of it lie on a horizontal line (see Liehr & Massopust 2020).
References
Fractals
Algorithms |
https://en.wikipedia.org/wiki/Cipher%20Department%20of%20the%20High%20Command%20of%20the%20Luftwaffe | Cipher Department of the High Command of the Luftwaffe was the signals intelligence and cryptanalytic agency of the German Air Ministry before and during World War II. In 1945, the unit was known as the Luftnachrichten Abteilung 350, abbreviated as OKL/Ln Abt 350 and formerly called the (). It was the successor in November 1944 of the unit formerly named as the Chi-Stelle Ob.d.L. (), which was often abbreviated to Chi-Stelle/ObdL.
History
As early as 1935, civilian employees of the Luftwaffe had been sent to fixed intercept stations of the German Army for training. A Luftwaffe officer, a technician and a civilian inspector who has been associated with the German Army Intelligence Service during World War I were transferred to the Luftwaffe Chi-Stelle. The two people canvassed for assistants among their old circle of acquaintances, former soldiers who had served in World War I as intercept technicians or cryptanalysts. Their numbers were no means sufficient for the task at hand. They consisted of people who at one time, either in civilian or military life, had received radio training or who were fluent in foreign languages. Among them were old soldiers, former seamen, professional travellers, adventurers and political refugees. In contrast to the Army, security measures taken in admitting people to the Agency were superficial, and a great number were found to be of questionable character. These trainees made training more difficult. Owing to their privileged position, they had a derogatory influence on the Luftwaffe Agency.
In creating the Chi-Stelle, the fundamental error was committing to choosing personnel indiscriminately, without any regard to their previous training for this special work. The civilian employees had training, but no training in Chi-Stelle type of work. The first technical equipment was very deficient. Old receivers from World War I were being used, and the installation alone was a technically difficult task, and therefore naturally unsuitable |
https://en.wikipedia.org/wiki/Ring%20%28programming%20language%29 | Ring is a dynamically typed, general-purpose programming language. It can be embedded in C/C++ projects, extended using C/C++ code and/or used as a standalone language. The supported programming paradigms are imperative, procedural, object-oriented, functional, meta, declarative using nested structures, and natural programming. The language is portable (Windows, Linux, macOS, Android, WebAssembly, etc.) and can be used to create console, GUI, web, game and mobile applications.
History
In 2009, Mahmoud Samir Fayed created a minor domain-specific language called Supernova that focuses on User interface (UI) creation and uses some ideas related to Natural Language Programming, then he realized the need for a new language that is general-purpose and can increase the productivity of natural language creation. Ring aims to offer a language focused on helping the developer with building natural interfaces and declarative DSLs.
Goals
The general goals behind Ring:
Applications programming language.
Productivity and developing high quality solutions that can scale.
Small and flexible language that can be embedded in C/C++ projects.
Simple language that can be used in education and introducing Compiler/VM concepts.
General-Purpose language that can be used for creating domain-specific libraries, frameworks and tools.
Practical language designed for creating the next version of the Programming Without Coding Technology software.
Examples
Hello World program
The same program can be written using different styles. Here is an example of the standard "Hello, World!" program using four different styles.
The first style:
see "Hello, World!"
The second style:
put "Hello, World!"
The third style:
load "stdlib.ring"
print("Hello, World!")
Another style: similar to xBase languages like Clipper and Visual FoxPro
? "Hello, World!"
Change the Keywords and Operators
Ring supports changing the language keywords and operators.
This could be done many times in the same |
https://en.wikipedia.org/wiki/GE/PAC%204000 | The GE/PAC 4000 computer systems are an obsolete line of computers manufactured by General Electric in Phoenix, Arizona beginning in the 1960s. PAC is short for Process Automation Computer, indicating the intended use of the systems for process control.
All 4000 systems are 24-bit, using fixed-point binary data, with between 1020 and 65,536 words of magnetic core memory, and a magnetic drum memory with 8192 to 262,144 word capacity. The CPU logic is implemented with discrete transistors. The systems can be configured with a wide variety of analog and digital inputs and outputs.
The 4020 is the low-end model of the system. Three models of the 4000, the 4040, 4050, and 4060 differ in storage speed— 5μsec, 3.4μsec, and 1.7 and 2.38μsec respectively— and by the implementation of a serial arithmetic unit on the 4040 vs. parallel on the other systems,
Software
The operating system for the 4000 series is called "G-E-MONITOR", a "skeleton real-time system program." "Several versions of MONTIOR are available, each tailored to the needs of a specific industry or process." Other software included Process Assembler Language (PAL), FORTRAN II, and Tabular Sequence Control (TASC). A set of memory load, dump, and change routines was provided.
Applications
A product brochure highlighted potential uses in the utility industry, food processing, manufacturing, the metal and chemical industry, paper and cement manufacturing, and petroleum.
References
Transistorized computers
General Electric |
https://en.wikipedia.org/wiki/Glossary%20of%20functional%20analysis | This is a glossary for the terminology in a mathematical field of functional analysis.
Throughout the article, unless stated otherwise, the base field of a vector space is the field of real numbers or that of complex numbers. Algebras are not assumed to be unital.
See also: List of Banach spaces.
*
A
B
C
D
F
G
H
I
K
L
N
O
P
Q
R
S
T
U
W
References
Bourbaki, Espaces vectoriels topologiques
M. Takesaki, Theory of Operator Algebras I, Springer, 2001, 2nd printing of the first edition 1979.
Further reading
Antony Wassermann's lecture notes at http://iml.univ-mrs.fr/~wasserm/
Jacob Lurie's lecture notes on a von Neumann algebra at https://www.math.ias.edu/~lurie/261y.html
Functional analysis |
https://en.wikipedia.org/wiki/Robust%20Regression%20and%20Outlier%20Detection | Robust Regression and Outlier Detection is a book on robust statistics, particularly focusing on the breakdown point of methods for robust regression. It was written by Peter Rousseeuw and Annick M. Leroy, and published in 1987 by Wiley.
Background
Linear regression is the problem of inferring a linear functional relationship between a dependent variable and one or more independent variables, from data sets where that relation has been obscured by noise. Ordinary least squares assumes that the data all lie near the fit line or plane, but depart from it by the addition of normally distributed residual values. In contrast, robust regression methods work even when some of the data points are outliers that bear no relation to the fit line or plane, possibly because the data draws from a mixture of sources or possibly because an adversarial agent is trying to corrupt the data to cause the regression method to produce an inaccurate result. A typical application, discussed in the book, involves the Hertzsprung–Russell diagram of star types, in which one wishes to fit a curve through the main sequence of stars without the fit being thrown off by the outlying giant stars and white dwarfs. The breakdown point of a robust regression method is the fraction of outlying data that it can tolerate while remaining accurate. For this style of analysis, higher breakdown points are better. The breakdown point for ordinary least squares is near zero (a single outlier can make the fit become arbitrarily far from the remaining uncorrupted data) while some other methods have breakdown points as high as 50%. Although these methods require few assumptions about the data, and work well for data whose noise is not well understood, they may have somewhat lower efficiency than ordinary least squares (requiring more data for a given accuracy of fit) and their implementation may be complex and slow.
Topics
The book has seven chapters. The first is introductory; it describes simple linear regres |
https://en.wikipedia.org/wiki/Hyper-IL-6 | Hyper-IL-6 is a designer cytokine, which was generated by the German biochemist Stefan Rose-John. Hyper-IL-6 is a fusion protein of the four-helical cytokine Interleukin-6 and the soluble Interleukin-6 receptor which are covalently linked by a flexible peptide linker. Interleukin-6 on target cells binds to a membrane bound Interleukin-6 receptor. The complex of Interleukin-6 and the Interleukin-6 receptor associate with a second receptor protein called gp130, which dimerises and initiates intracellular signal transduction. Gp130 is expressed on all cells of the human body whereas the Interleukin-6 receptor is only found on few cells such as hepatocytes and some leukocytes. Neither Interleukin-6 nor the Interleukin-6 receptor have a measurable affinity for gp130. Therefore, cells, which only express gp130 but no Interleukin-6 receptor are not responsive to Interleukin-6. It was found, however, that the membrane-bound Interleukin-6 receptor can be cleaved from the cell membrane generating a soluble Interleukin-6 receptor. The soluble Interleukin-6 receptor can bind the ligand Interleukin-6 with similar affinity as the membrane-bound Interleukin-6 receptor and the complex of Interleukin-6 and the soluble Interleukin-6 receptor can bind to gp130 on cells, which only express gp130 but no Interleukin-6 receptor. The mode of signaling via the soluble Interleukin-6 receptor has been named Interleukin-6 trans-signaling whereas Interleukin-6 signaling via the membrane-bound Interleukin-6 receptor is referred to as Interleukin-6 classic signaling. Therefore, the generation of the soluble Interleukin-6 receptor enables cells to respond to Interleukin-6, which in the absence of soluble Interleukin-6 receptor would be completely unresponsive to the cytokine.
Molecular construction of Hyper-IL-6
In order to generate a molecular tool to discriminate between Interleukin-6 classic signaling and Interleukin-6 trans-signaling, a cDNA coding for human Interleukin-6 and a cDNA coding f |
https://en.wikipedia.org/wiki/Kirkpatrick%E2%80%93Reisch%20sort | Kirkpatrick–Reisch sorting is a fast sorting algorithm for items with limited-size integer keys. It is notable for having an asymptotic time complexity that is better than radix sort.
References
Sorting algorithms |
https://en.wikipedia.org/wiki/Ecotron | An Ecotron is an experimental instrument in ecology consisting of a controlled environment which makes it possible to simultaneously condition the environment of natural, simplified, or completely artificial ecosystems and measure the processes generated by living beings present in these ecosystems, in particular the flow of matter and energy.
Design
Its principle is to confine ecosystems in totally or partially waterproof enclosures which are permeable to energy flow and capable of generating a range of physical and chemical conditions applied to terrestrial or aquatic ecosystems, continental or marine. Environmental control and real-time measurements are precise enough to test hypotheses or operating models. For this purpose, the enclosures are fitted with significant equipment allowing continuous measurement of fluxes, states or biological characteristics. Other specific measurements, in situ and ex situ, on samples taken complete these online measurements. A sufficient number of independent confinement chambers is necessary to study several interacting factors in a framework of statistical inference.
Depending on the case, we speak of a macrocosm when the space is large enough to study several m3 of reconstituted ecosystem over a period of time, generally measured in years (3-5 years or more for example), of microcosm for volumes measuring in cubic decimeters (study of fungal, bacterial, soil ecosystems, etc.) and mesocosm for intermediate situations.
References
Bibliography
Lawton, J. H., Naeem, S., Woodfin, R. M., Brown, V. K., Gange, A., Godfray, H. J. C., Heads, P. A., Lawler, S., Magda, D., Thomas, C. D., Thompson, L. J. & Young, S. (1993) "The Ecotron - a Controlled Environmental Facility for the Investigation of Population and Ecosystem Processes." Phil. Trans. R. Soc. B, 341, 181-194.
Lawton, J. H. (1996) "The Ecotron facility at Silwood Park: The value of big bottle" experiments. Ecology, 77, 665-669.
Loreau, M. (1998) Biodiversité et fonction |
https://en.wikipedia.org/wiki/Weyl%20expansion | In physics, the Weyl expansion, also known as the Weyl identity or angular spectrum expansion, expresses an outgoing spherical wave as a linear combination of plane waves. In a Cartesian coordinate system, it can be denoted as
,
where , and are the wavenumbers in their respective coordinate axes:
.
The expansion is named after Hermann Weyl, who published it in 1919. The Weyl identity is largely used to characterize the reflection and transmission of spherical waves at planar interfaces; it is often used to derive the Green's functions for Helmholtz equation in layered media. The expansion also covers evanescent wave components. It is often preferred to the Sommerfeld identity when the field representation is needed to be in Cartesian coordinates.
The resulting Weyl integral is commonly encountered in microwave integrated circuit analysis and electromagnetic radiation over a stratified medium; as in the case for Sommerfeld integral, it is numerically evaluated. As a result, it is used in calculation of Green's functions for method of moments for such geometries. Other uses include the descriptions of dipolar emissions near surfaces in nanophotonics, holographic inverse scattering problems, Green's functions in quantum electrodynamics and acoustic or seismic waves.
See also
Angular spectrum method
Fourier optics
Green's function
Plane wave expansion
Sommerfeld identity
References
Sources
Mathematical identities
Mathematical physics
Electrodynamics
Wave mechanics |
https://en.wikipedia.org/wiki/Thirst%20trap | A thirst trap is a type of social media post intended to entice viewers sexually. It refers to a viewer's "thirst", a colloquialism likening sexual frustration to dehydration, implying desperation, with the afflicted individual being described as "thirsty." The phrase entered into the lexicon in the late 1990s, but is most related to Internet slang that developed in the early 2010s. Its meaning has changed over time, previously referring to a graceless need for approval, affection or attention. A thirsty comment is usually a comment that wants the sexual attention of someone.
History
The usage of the phrase thirst trap derived from selfie culture. Though its origin is ambiguous, thirst trap was used in the 1999 book, Running for Dummies authored by Florence Griffith Joyner and John Hanc.
The authors defined a body's need for hydration prior to the onset of thirst and the false sense that the immediate thirst was quenched with the first intake of fluid. To avoid the thirst trap, the authors suggested further intake of fluids even though the body's "thirsty message" had been sated.
The term thirst trap re-emerged on Twitter and Urban Dictionary in 2011, and throughout the years with the rise of Snapchat, Instagram, and online dating apps such as Tinder. In 2011, it was defined by Urban Dictionary as "any statement used to intentionally create attention or 'thirst'."
In 2018, it was reported to have entered common usage, as media sources including The New York Times and GQ started using the expression without definition.
Usage of the term
Often, the term thirst trap describes an attractive picture of an individual that they post online.
Thirst trap can also describe a digital heartthrob. For instance, Canadian prime minister Justin Trudeau has been described as a political thirst trap.
It has also been described as a modern form of "fishing for compliments".
Motivation
There can be several motivations behind thirst trapping. People can seek "likes" and |
https://en.wikipedia.org/wiki/Stable%20principal%20bundle | In mathematics, and especially differential geometry and algebraic geometry, a stable principal bundle is a generalisation of the notion of a stable vector bundle to the setting of principal bundles. The concept of stability for principal bundles was introduced by Annamalai Ramanathan for the purpose of defining the moduli space of G-principal bundles over a Riemann surface, a generalisation of earlier work by David Mumford and others on the moduli spaces of vector bundles.
Many statements about the stability of vector bundles can be translated into the language of stable principal bundles. For example, the analogue of the Kobayashi–Hitchin correspondence for principal bundles, that a holomorphic principal bundle over a compact Kähler manifold admits a Hermite–Einstein connection if and only if it is polystable, was shown to be true in the case of projective manifolds by Subramanian and Ramanathan, and for arbitrary compact Kähler manifolds by Anchouche and Biswas.
Definition
The essential definition of stability for principal bundles was made by Ramanathan, but applies only to the case of Riemann surfaces. In this section we state the definition as appearing in the work of Anchouche and Biswas which is valid over any Kähler manifold, and indeed makes sense more generally for algebraic varieties. This reduces to Ramanathan's definition in the case the manifold is a Riemann surface.
Let be a connected reductive algebraic group over the complex numbers . Let be a compact Kähler manifold of complex dimension . Suppose is a holomorphic principal -bundle over . Holomorphic here means that the transition functions for vary holomorphically, which makes sense as the structure group is a complex Lie group. The principal bundle is called stable (resp. semi-stable) if for every reduction of structure group for a maximal parabolic subgroup where is some open subset with the codimension , we have
Here is the relative tangent bundle of the fibre bundle otherwise kn |
https://en.wikipedia.org/wiki/Stability%20%28algebraic%20geometry%29 | In mathematics, and especially algebraic geometry, stability is a notion which characterises when a geometric object, for example a point, an algebraic variety, a vector bundle, or a sheaf, has some desirable properties for the purpose of classifying them. The exact characterisation of what it means to be stable depends on the type of geometric object, but all such examples share the property of having a minimal amount of internal symmetry, that is such stable objects have few automorphisms. This is related to the concept of simplicity in mathematics, which measures when some mathematical object has few subobjects inside it (see for example simple groups, which have no non-trivial normal subgroups). In addition to stability, some objects may be described with terms such as semi-stable (having a small but not minimal amount of symmetry), polystable (being made out of stable objects), or unstable (having too much symmetry, the opposite of stable).
Background
In many areas of mathematics, and indeed within geometry itself, it is often very desirable to have highly symmetric objects, and these objects are often regarded as aesthetically pleasing. However, high amounts of symmetry are not desirable when one is attempting to classify geometric objects by constructing moduli spaces of them, because the symmetries of these objects cause the formation of singularities, and obstruct the existence of universal families.
The concept of stability was first introduced in its modern form by David Mumford in 1965 in the context of geometric invariant theory, a theory which explains how to take quotients of algebraic varieties by group actions, and obtain a quotient space that is still an algebraic variety, a so-called categorical quotient. However the ideas behind Mumford's work go back to the invariant theory of David Hilbert in 1893, and the fundamental concepts involved date back even to the work of Bernhard Riemann on constructing moduli spaces of Riemann surfaces. Since the |
https://en.wikipedia.org/wiki/Timeout%20Detection%20and%20Recovery | Timeout Detection and Recovery or TDR is a feature of the Windows operating system (OS) introduced in Windows Vista. It detects response problems from a graphics card (GPU), and if a timeout occurs, the OS will attempt a card reset to recover a functional and responsive desktop environment. However, if the attempt was unsuccessful, it results in the Blue Screen of Death (BSOD). The recovery tries to mitigate the scenario where an end user superfluously reboots their device should it become unresponsive.
Timeline
When the GPU takes more than the allotted time to process a request, the system's GPU scheduler will pick up the anomaly. It then tries to preempt the particular task, this operation has the TDR timeout which is 2 seconds by default.
Once the timeout is up and the task is not completed or preempted, the kernel determines that the GPU is frozen and proceeds to inform the respective driver about the detected timeout. It is then the driver's responsibility to properly reset and reinitialize the underlying GPU.
The OS will then do a bunch of other recovery steps needed for the system to regain responsiveness. If the entire operation was successful, the end user might see some visual artefacts and a message will be shown on the screen describing what had happened ("Display driver stopped responding and has recovered."), else a BSOD might ensue.
Possible causes
There are multiple probable causes should a recovery fail, causing an inevitable BSOD:
Outdated drivers
GPU/Hardware issue
Overloading the GPU
Corrupted application/system files/driver
BSOD stop codes
Possible BSOD stop codes emitted if the attempted recovery failed:
VIDEO_TDR_FAILURE (Bug check value: 0x116), recovery and resetting of display driver from a TDR timeout failed.
See also
Windows Display Driver Model
Display driver
DirectX
Vulkan
References
Further reading
Timeout Detection & Recovery (TDR) Nvidia
TDR in Windows 8 and later - Windows drivers | Microsoft Learn
Thread Synchronizat |
https://en.wikipedia.org/wiki/Laguerre%20transformations | The Laguerre transformations or axial homographies are an analogue of Möbius transformations over the dual numbers. When studying these transformations, the dual numbers are often interpreted as representing oriented lines on the plane. The Laguerre transformations map lines to lines, and include in particular all isometries of the plane.
Strictly speaking, these transformations act on the dual number projective line, which adjoins to the dual numbers a set of points at infinity. Topologically, this projective line is equivalent to a cylinder. Points on this cylinder are in a natural one-to-one correspondence with oriented lines on the plane.
Definition
A Laguerre transformation is a linear fractional transformation where are all dual numbers, lies on the dual number projective line, and is not a zero divisor.
A dual number is a hypercomplex number of the form where but . This can be compared to the complex numbers which are of the form where .
The points of the dual number projective line can be defined equivalently in two ways:
The usual set of dual numbers, but with some additional "points at infinity". Formally, the set is . The points at infinity can be expressed as where is an arbitrary real number. Different values of correspond to different points at infinity. These points are infinite because is often understood as being an infinitesimal number, and so is therefore infinite.
The homogeneous coordinates [x : y] with x and y dual numbers such that the ideal that they generate is the whole ring of dual numbers. The ring is viewed through the injection x ↦ [x : 1]. The projective line includes points [1 : yε].
Line coordinates
A line which makes an angle with the x-axis, and whose x-intercept is denoted , is represented by the dual number
The above doesn't make sense when the line is parallel to the x-axis. In that case, if then set where is the y-intercept of the line. This may not appear to be valid, as one is dividing by a zer |
https://en.wikipedia.org/wiki/Contact%20region | A Contact Region is a concept in robotics which describes the region between an object and a robot’s end effector. This is used in object manipulation planning, and with the addition of sensors built into the manipulation system, can be used to produce a surface map or contact model of the object being grasped.
In Robotics
For a robot to autonomously grasp an object, it is necessary for the robot to have an understanding of its own construction and movement capabilities (described through the math of inverse kinematics), and an understanding of the object to be grasped. The relationship between these two is described through a contact model, which is a set of the potential points of contact between the robot and the object being grasped. This, in turn, is used to create a more concrete mathematical representation of the grasp to be attempted, which can then be computed through path planning techniques and executed.
In Mathematics
Depending on the complexity of the end effector, or through usage of external sensors such as a Lidar or Depth camera, a more complex model of the planes involved in the object being grasped can be produced. In particular, sensors embedded in the fingertips of an end effector have been demonstrated to be an effective approach for producing a surface map from a given contact region. Through knowledge of the robot's position of each individual finger, the location of the sensors in each finger, and the amount of force being exerted by the object onto each sensor, points of contact can be calculated. These points of contact can then be turned into a three-dimensional ellipsis, producing a surface map of the object.
Applications
In hand manipulation is a typical use case. A robot hand interacts with static and deformable objects, described with soft-body dynamics. Sometimes, additional tools has to be controlled by the robot hand for example a screwdriver. Such interaction produces a complex situation in which the robot hand has similar c |
https://en.wikipedia.org/wiki/Sikta%20Irrigation%20Project | Sikta Irrigation Project is one of the National Pride Projects of Nepal. The intake is in the Rapti river in western Nepal. There are two canals with the capacity of 50 m3/s each. The length of canal is 45.25 kilometres in the western section and 53 kilometres in the eastern section. The canals are constituted into 3 phases. As of 2019, 60% of the project has been completed.
Project Development
The feasibility study of the project was done by Lahmeyer International GmbH from Germany in 1980. In 1983, the Department of Hydrology and Metrology revised the study. In 2004, the Irrigation Development Programme under the European Union concluded that the project is feasible which led the government to start the project by its own resources.
The initial project cost in 2005-06 was NPR 12.8 billion and estimated to be completed by 2014–15. The project is still under construction and is estimated to be complete by 2020. The project is expected to rise to NPR 25.02 billion. In 2019, the project completion was 60%.
The contractor for construction is CTC Kalika Joint Venture Pvt Ltd. The project targets to irrigate 42,000 hectares of land in Banke District.
Damages and Accidents
In 2016, a canal section collapsed due to weak soil properties during testing at the flow of 5m³/s.
In September 2017, damages were reported in multiple section of the canal. The damage was due to cross-drainage problem in the canal. Most of the damage were found near the siphon areas.
In 2018, damages in canal were reported during testing.
Corruption
The national Commission for Investigation of Abuse of Authority (CIAA) has lodged a corruption case of over NPR 2 billion in this project. The case was filed against former minister and chief of Kalika Construction Bikram Pandey over the construction of a canal and 20 other staffs. CIAA has made claims of Rs 2.13 billion from Bikram Pandey, NPR 1.56 billion from Dilip Bahadur Karki and NPR 593.45 million from Saroj Chandra Pandit. It also claims Rs |
https://en.wikipedia.org/wiki/Cholesterol%20signaling | Cholesterol is a cell signaling molecule that is highly regulated in eukaryotic cell membranes. In human health, its effects are most notable in inflammation, metabolic syndrome, and neurodegeneration. At the molecular level, cholesterol primarily signals by regulating clustering of saturated lipids and proteins that depend on clustering for their regulation.
Mechanism
Lipid rafts are loosely defined as clusters of cholesterol and saturated lipids forming regions of lipid heterogeneity in cellular membranes (e.g., the ganglioside GM1). The association of proteins to lipid rafts is cholesterol dependent and regulates the proteins' function (e.g., substrate presentation).
Lipid raft regulation
Cholesterol regulates the function of several membrane proteins associated with lipid rafts. It does so by controlling the formation or depletion of lipid rafts in the plasma membrane. The lipid rafts house the membrane proteins and forming or depleting the lipid rafts moves the proteins in or out of the raft environment, thereby exposing them to a new environment that can activate or deactivate the proteins. For example, cholesterol directly regulates the affinity of palmitoylated proteins for GM1 containing lipid rafts. Cholesterol signaling through lipid rafts can be attenuated by phosphatidylinositol 4,5 bisphosphate signaling (PIP2). PIP2 contains mostly polyunsaturated lipids that partition away from saturated lipids. Proteins that bind both lipid rafts and PIP2 are negatively regulated by high levels of PIP2. This effect was observed with phospholipase D.
In the brain, astrocytes make the cholesterol and transport it to nerves to control their function.
Substrate presentation
A protein subject to regulation through raft-associated translocation can undergo activation upon substrate presentation. For instance, an enzyme that translocates within the membrane towards its substrate can be activated by localizing to the substrate, irrespective of any conformational change |
https://en.wikipedia.org/wiki/Buchdahl%27s%20theorem | In general relativity, Buchdahl's theorem, named after Hans Adolf Buchdahl, makes more precise the notion that there is a maximal sustainable density for ordinary gravitating matter. It gives an inequality between the mass and radius that must be satisfied for static, spherically symmetric matter configurations under certain conditions. In particular, for areal radius , the mass must satisfy
where is the gravitational constant and is the speed of light. This inequality is often referred to as Buchdahl's bound. The bound has historically also been called Schwarzschild's limit as it was first noted by Karl Schwarzschild to exist in the special case of a constant density fluid. However, this terminology should not be confused with the Schwarzschild radius which is notably smaller than the radius at the Buchdahl bound.
Theorem
Given a static, spherically symmetric solution to the Einstein equations (without cosmological constant) with matter confined to areal radius that behaves as a perfect fluid with a density that does not increase outwards. (An areal radius corresponds to a sphere of surface area . In curved spacetime the proper radius of such a sphere is not necessarily .) Assumes in addition that the density and pressure cannot be negative. The mass of this solution must satisfy
For his proof of the theorem, Buchdahl uses the Tolman-Oppenheimer-Volkoff (TOV) equation.
Significance
The Buchdahl theorem is useful when looking for alternatives to black holes. Such attempts are often inspired by the information paradox; a way to explain (part of) the dark matter; or to criticize that observations of black holes are based on excluding known astrophysical alternatives (such as neutron stars) rather than direct evidence. However, to provide a viable alternative it is sometimes needed that the object should be extremely compact and in particular violate the Buchdahl inequality. This implies that one of the assumptions of Buchdahl's theorem must be invalid. A |
https://en.wikipedia.org/wiki/Oracle%20complexity%20%28optimization%29 | In mathematical optimization, oracle complexity is a standard theoretical framework to study the computational requirements for solving classes of optimization problems. It is suitable for analyzing iterative algorithms which proceed by computing local information about the objective function at various points (such as the function's value, gradient, Hessian etc.). The framework has been used to provide tight worst-case guarantees on the number of required iterations, for several important classes of optimization problems.
Formal description
Consider the problem of minimizing some objective function (over some domain ), where is known to belong to some family of functions . Rather than direct access to , it is assumed that the algorithm can obtain information about via an oracle , which given a point in , returns some local information about in the neighborhood of . The algorithm begins at some initialization point , uses the information provided by the oracle to choose the next point , uses the additional information to choose the following point , and so on.
To give a concrete example, suppose that (the -dimensional Euclidean space), and consider the gradient descent algorithm, which initializes at some point and proceeds via the recursive equation
,
where is some step size parameter. This algorithm can be modeled in the framework above, where given any , the oracle returns the gradient , which is then used to choose the next point .
In this framework, for each choice of function family and oracle , one can study how many oracle calls/iterations are required, to guarantee some optimization criterion (for example, ensuring that the algorithm produces a point such that for some ). This is known as the oracle complexity of this class of optimization problems: Namely, the number of iterations such that on one hand, there is an algorithm that provably requires only this many iterations to succeed (for any function in ), and on the other hand, there |
https://en.wikipedia.org/wiki/Zynn | Zynn was a Chinese video-sharing social networking service owned by Kuaishou, a Beijing-based internet technology company established in 2011 by Su Hua and Cheng Yixiao. It was used to create and share short videos, and it pays its users for using the app and referring others. Zynn was launched on May 7, 2020. It became the most-downloaded app in the App Store in the same month. It has also been criticized for being a "pyramid scheme", and it has faced accusations of plagiarism and stealing content. Aside from Zynn in North America, Kuaishou is available under the name Kwai in Russia, South Korea, Japan, Thailand, Vietnam, Philippines, Malaysia, Indonesia, Brazil, America, India, and the Middle East. Kwai used to be available in Australia and the United States on the App Store, but was removed at an unknown date. Zynn was permanently shut down on the 20th of August, 2021.
History
In 2011, entrepreneur Su Hua co-founded Kuaishou with business partner Cheng Yixiao. Originally a GIF-making app, Kuaishou soon moved to short video content. Su Hua also serves as the current Kuaishou CEO.
In December 2019, Chinese internet conglomerate Tencent invested $2 billion in Kuaishou, reportedly to compete with rival ByteDance. In December 2019, Kuaishou acquired an app developer called Owlii, which is the developer of Zynn. Zynn was developed to be a North American Market edition of Kuaishou.
On May 7, 2020, the app was launched and it was downloaded over 2 million times in that month. On May 12, 2020, Kuaishou filed a lawsuit seeking compensation for "unfair competition", and accused Douyin, the sister app of TikTok, of "interfering" with search results on app stores.
Zynn shut down on the 20th of August, 2021
Features
Zynn allows its users to create, edit and share short videos of themselves. Its interface has been described as a "complete clone" of TikTok, its main competitor.
The Zynn app was unique in the way that they paid users for using the platform. Each user earn |
https://en.wikipedia.org/wiki/Metrizable%20topological%20vector%20space | In functional analysis and related areas of mathematics, a metrizable (resp. pseudometrizable) topological vector space (TVS) is a TVS whose topology is induced by a metric (resp. pseudometric). An LM-space is an inductive limit of a sequence of locally convex metrizable TVS.
Pseudometrics and metrics
A pseudometric on a set is a map satisfying the following properties:
;
Symmetry: ;
Subadditivity:
A pseudometric is called a metric if it satisfies:
Identity of indiscernibles: for all if then
Ultrapseudometric
A pseudometric on is called a ultrapseudometric or a strong pseudometric if it satisfies:
Strong/Ultrametric triangle inequality:
Pseudometric space
A pseudometric space is a pair consisting of a set and a pseudometric on such that 's topology is identical to the topology on induced by We call a pseudometric space a metric space (resp. ultrapseudometric space) when is a metric (resp. ultrapseudometric).
Topology induced by a pseudometric
If is a pseudometric on a set then collection of open balls:
as ranges over and ranges over the positive real numbers,
forms a basis for a topology on that is called the -topology or the pseudometric topology on induced by
: If is a pseudometric space and is treated as a topological space, then unless indicated otherwise, it should be assumed that is endowed with the topology induced by
Pseudometrizable space
A topological space is called pseudometrizable (resp. metrizable, ultrapseudometrizable) if there exists a pseudometric (resp. metric, ultrapseudometric) on such that is equal to the topology induced by
Pseudometrics and values on topological groups
An additive topological group is an additive group endowed with a topology, called a group topology, under which addition and negation become continuous operators.
A topology on a real or complex vector space is called a vector topology or a TVS topology if it makes the operations of vector addition and scalar multiplicati |
https://en.wikipedia.org/wiki/LST%201564 | LST 1564:2000 is a character encoding used to write the Lithuanian language. It is a modification of ISO/IEC 8859-13 to support the accented Lithuanian letters.
Codepage layout
The following table shows LST 1564. Each character is shown with its equivalent Unicode code point. Only the second half of the table (code points 128–255) is shown, the first half (code points 0–127) being the same as ASCII.
References
Character sets
Lithuanian language |
https://en.wikipedia.org/wiki/LST%201590-4 | LST 1590-4 is a character encoding used to write the Lithuanian language. It is a modification of Windows-1257 to support additional accented letters and phonetic notation.
Codepage layout
The following table shows LST 1590–4. Each character is shown with its equivalent Unicode code point. Only the second half of the table (code points 128–255) is shown, the first half (code points 0–127) being the same as ASCII.
References
Character sets
Lithuanian language |
https://en.wikipedia.org/wiki/Tyson%20Fury%20vs.%20Deontay%20Wilder%20III | Tyson Fury vs. Deontay Wilder III billed as "Once And For All" was a professional boxing trilogy fight between WBC and The Ring heavyweight champion, Tyson Fury, and former WBC heavyweight champion, Deontay Wilder. The bout took place at T-Mobile Arena in Paradise, Nevada on October 9, 2021. The fight, which Fury won via eleventh-round knockout, was widely regarded as the best fight of the year and one of the greatest heavyweight fights of all time, winning the award for The Ring magazine Fight of the Year 2021.
Background
Fury and Wilder first fought in December 2018, with the bout ending in a controversial draw. The pair had a rematch in February 2020, with Fury emerging victorious via seventh-round technical knockout to capture the WBC and vacant Ring magazine heavyweight titles. Wilder initiated a contractual rematch clause in March, with the bout initially being scheduled for July 18. However, due to Wilder still recovering from surgery and concerns over the COVID-19 pandemic, the bout was postponed to October. The date was again pushed back to December due to the COVID-19 lockdown restrictions that would limit fan attendance. After ESPN was unwilling to televise the bout as the event would conflict with their NFL schedule, it was suggested the date be pushed back for a third time. Upon hearing the news, Fury announced that he was walking away from the fight, stating, "they asked me if I would agree to push it to December. I agreed to Dec. 19. Then they tried to change the date again into next year. I've been training. I'm ready. When they tried moving off Dec. 19 and pushing to next year, enough was enough. I've moved on." Wilder responded to the comments by releasing a video on social media, accusing Fury of cheating in their February 2020 fight.
With Fury's team insisting the rematch clause had now expired, and Wilder's team insisting the opposite, the teams entered into a mediation process in an attempt to solve the issue, with a legally binding outcome |
https://en.wikipedia.org/wiki/Self-sovereign%20identity | Self-sovereign identity (SSI) is an approach to digital identity that gives individuals control over the information they use to prove who they are to websites, services, and applications across the web. Without SSI, individuals with persistent accounts (identities) across the internet must rely on a number of large identity providers, such as Facebook (Facebook Connect) and Google (Google Sign-In), that have control of the information associated with their identity. If a user chooses not to use a large identity provider, then they have to create new accounts with each service provider, which fragments their web experiences. Self-sovereign identity offers a way to avoid these two undesirable alternatives. In a self-sovereign identity system, the user accesses services in a streamlined and secure manner, while maintaining control over the information associated with their identity.
Background
The TCP/IP protocol provides identifiers for machines, but not for the people and organisations operating the machines. This makes the network-level identifiers on the internet hard to trust and rely on for information and communication for a number of reasons: 1) hackers can easily change a computer’s hardware or IP address, 2) services provide identifiers for the user, not the network. The absence of reliable identifiers is one of the primary sources of cybercrime, fraud, and threats to privacy on the internet.
With the advent of blockchain technology, a new model for decentralized identity emerged in 2015. The FIDO Alliance proposed an identity model that was no longer account-based, but identified people through direct, private, peer-to-peer connections secured by public/private key cryptography. Self-Sovereign Identity (SSI) summarises all components of the decentralized identity model: digital wallets, digital credentials, and digital connections.
Technical aspects
SSI addresses the difficulty of establishing trust in an interaction. In order to be trusted, one party |
https://en.wikipedia.org/wiki/Tensor%20sketch | In statistics, machine learning and algorithms, a tensor sketch is a type of dimensionality reduction that is particularly efficient when applied to vectors that have tensor structure. Such a sketch can be used to speed up explicit kernel methods, bilinear pooling in neural networks and is a cornerstone in many numerical linear algebra algorithms.
Mathematical definition
Mathematically, a dimensionality reduction or sketching matrix is a matrix , where , such that for any vector
with high probability.
In other words, preserves the norm of vectors up to a small error.
A tensor sketch has the extra property that if for some vectors such that , the transformation can be computed more efficiently. Here denotes the Kronecker product, rather than the outer product, though the two are related by a flattening.
The speedup is achieved by first rewriting , where denotes the elementwise (Hadamard) product.
Each of and can be computed in time and , respectively; including the Hadamard product gives overall time . In most use cases this method is significantly faster than the full requiring time.
For higher-order tensors, such as , the savings are even more impressive.
History
The term tensor sketch was coined in 2013 describing a technique by Rasmus Pagh from the same year.
Originally it was understood using the fast Fourier transform to do fast convolution of count sketches.
Later research works generalized it to a much larger class of dimensionality reductions via Tensor random embeddings.
Tensor random embeddings were introduced in 2010 in a paper on differential privacy and were first analyzed by Rudelson et al. in 2012 in the context of sparse recovery.
Avron et al.
were the first to study the subspace embedding properties of tensor sketches, particularly focused on applications to polynomial kernels.
In this context, the sketch is required not only to preserve the norm of each individual vector with a certain probability but to preserve the norm of al |
https://en.wikipedia.org/wiki/Code%20page%201040 | Code page 1040 (CCSID 1040), also known as Korean PC Data Extended, is a single byte character set (SBCS) used by IBM in its PC DOS operating system for Hangul. It is an extended version of the 8-bit form of the N-byte Hangul Code first specified by the 1974 edition of KS C 5601 (compare the relationship between Code page 1041 and JIS X 0201 for katakana).
Codepage layout
References
1040 |
https://en.wikipedia.org/wiki/RNP%20world | The RNP world is a hypothesized intermediate period in the origin of life characterized by the existence of ribonucleoproteins. The period followed the hypothesized RNA world and ended with the formation of DNA and contemporary proteins. In the RNP world, RNA molecules began to synthesize peptides. These would eventually become proteins which have since assumed most of the diverse functions RNA performed previously. This transition paved the way for DNA to replace RNA as the primary store of genetic information, leading to life as we know it.
Principle of concept
Thomas Cech, in 2009, proposed the existence of the RNP world after his observation of apparent differences in the composition of catalysts in the two most fundamental processes that maintain and express genetic systems. The maintenance process, DNA replication and transcription, is accomplished purely by protein polymerases. The gene expression process, mRNA splicing and protein synthesis, is catalyzed by RNP complexes (the spliceosome and ribosome).
The difference between how these processes catalyze can be reconciled with the RNA world theory. As an older molecule than DNA, RNA had a hybrid RNA-protein-based maintenance system. Our current DNA world could have resulted from the gradual replacement of RNA catalysis machines with proteins. In this view, ribonucleoproteins and nucleotide-based cofactors are relics of an intermediary era, the RNP world.
References
Ribonucleoproteins
RNA
DNA
Peptides
Proteins |
https://en.wikipedia.org/wiki/Code%20page%201043 | Code page 1043 (CCSID 1043), also known as Traditional Chinese PC Data Extended, is a single byte character set (SBCS) used by IBM in its PC DOS operating system.
This code page is intended for use with code page 927 (Traditional Chinese double byte character set). It is an extension of Code page 904.
Codepage layout
References
1043 |
https://en.wikipedia.org/wiki/Code%20page%201046 | Code page 1046 (CCSID 1046 and euro sign extended CCSID 9238), also known as Arabic Extended-Euro, is used by IBM platforms in Egypt, Iraq, Jordan, Saudi Arabia, and Syria for Arabic.
Codepage layout
Code page 1029
Code page 1029 is an older variant of Code page 1046.
References
1046 |
https://en.wikipedia.org/wiki/Code%20page%201115 | Code page 1115 (CCSID 1115), also known as Simplified Chinese PC Data, is a single byte character set (SBCS) used by IBM in its PC DOS operating system in China.
This code page is intended for use with code page 1380 (Simplified Chinese double byte character set). Together, code pages 1115 and 1380 make up 1381.
Code points 0x01 through 0x1F and x7F represent either graphic or control characters depending on the context.
Code points 0x8C through 0xFE are used as lead bytes for double byte characters.
Codepage layout
References
1115 |
https://en.wikipedia.org/wiki/ARM%20Cortex-X1 | The ARM Cortex-X1 is a central processing unit implementing the ARMv8.2-A 64-bit instruction set designed by ARM Holdings' Austin design centre as part of ARM's Cortex-X Custom (CXC) program.
Design
The Cortex-X1 design is based on the ARM Cortex-A78, but redesigned for purely performance instead of a balance of performance, power, and area (PPA).
The Cortex-X1 is a 5-wide decode out-of-order superscalar design with a 3K macro-OP (MOPs) cache. It can fetch 5 instructions and 8 MOPs per cycle, and rename and dispatch 8 MOPs, and 16 µOPs per cycle. The out-of-order window size has been increased to 224 entries. The backend has 15 execution ports with a pipeline depth of 13 stages and the execution latencies consists of 10 stages. It also features 4x128b SIMD units.
ARM claims the Cortex-X1 offers 30% faster integer and 100% faster machine learning performance than the ARM Cortex-A77.
The Cortex-X1 supports ARM's DynamIQ technology, expected to be used as high-performance cores when used in combination with the ARM Cortex-A78 mid and ARM Cortex-A55 little cores.
Architecture changes in comparison with ARM Cortex-A78
Around 20% performance improvement (+30% from A77)
30% faster integer
100% faster machine learning performance
Out-of-order window size has been increased to 224 entries (from 160 entries)
Up to 4x128b SIMD units (from 2x128b)
15% more silicon area
5-way decode (from 4-way)
8 MOPs/cycle decoded cache bandwidth (from 6 MOPs/cycle)
64 KB L1D + 64 KB L1I (from 32/64 KB L1)
Up to 1 MB/core L2 cache (from 512 KB/core max)
Up to 8 MB L3 cache (from 4 MB max)
Licensing
The Cortex-X1 is available as SIP core to partners of their Cortex-X Custom (CXC) program, and its design makes it suitable for integration with other SIP cores (e.g. GPU, display controller, DSP, image processor, etc.) into one die constituting a system on a chip (SoC).
Usage
Samsung Exynos 2100
Qualcomm Snapdragon 888(+)
Google Tensor
See also
ARM Cortex-A78, related |
https://en.wikipedia.org/wiki/Erd%C5%91s%20sumset%20conjecture | In additive combinatorics, the Erdős sumset conjecture is a conjecture which states that if a subset of the natural numbers has a positive upper density then there are two infinite subsets and of such that contains the sumset . It was posed by Paul Erdős, and was proven in 2019 in a paper by Joel Moreira, Florian Richter and Donald Robertson.
See also
List of conjectures by Paul Erdős
Notes
Conjectures
Conjectures that have been proved
Paul Erdős
Combinatorics |
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