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https://en.wikipedia.org/wiki/Tire%20model | In vehicle dynamics, a tire model is a type of multibody simulation used to simulate the behavior of tires. In current vehicle simulator models, the tire model is the weakest and most difficult part to simulate.
Tire models can be classified on their accuracy and complexity, in a spectrum that goes from more simple empirical models to more complex physical models that are theoretically grounded. Empirical models include Hans B. Pacejka's Magic Formula, while physically based models include brush models (although they are still quite simplified), and more complex and detailed physical models include RMOD-K, FTire and Hankook. Theoretically-based models can be in turn classified from more approximative to more complex ones, going for example from the solid model, to the rigid ring model, to the flexural (elastic) ring model (like the Fiala model), and the most complex ones based on finite element methods.
Brush models were very popular in the 1960s and '70s, after which Pacejka's models became widespread for many applications.
Classification by purpose
Driving dynamics models
Brush model (Dugoff, Fancher and Segel, 1970)
Hohenheim tire model (physical approach [1] )
Pacejka Magic Formula Tire (Bakker, Nyborg and Pacejka, 1987)
TameTire (semi-physical approach)
TMeasy (semi-physical approach)
Stretched string tire model (Fiala 1954)
Comfort models
BRIT (Brush and Ring Tire)
CDTire (Comfort and Durability Tire)
Ctire (Comfort tire)
Dtire (Dynamical Nonlinear Spatial Tire Model)
FTire (Flexible Structure Tire Model)
RMOD-K (Comfort and Durability Tire)
SWIFT (Short Wavelength Intermediate Frequency Tire) (Besselink, Pacejka, Schmeitz, & Jansen, 2005)
Applications
Fully physics-based tire models have been typically too computational expensive to be run in realtime driving simulations. For example, to since CDTire/3D, a physics-based tire model, cannot be run in realtime, for realtime applications typically an equivalent semi-empirical "magic formula" type o |
https://en.wikipedia.org/wiki/Rank-width | Rank-width is a graph width parameter used in graph theory and parameterized complexity, and defined using linear algebra.
It is defined from hierarchical clusterings of the vertices of a given graph, which can be visualized as ternary trees having the vertices as their leaves. Removing any edge from such a tree disconnects it into two subtrees and partitions the vertices into two subsets. The graph edges that cross from one side of the partition to the other can be described by a biadjacency matrix; for the purposes of rank-width, this matrix is defined over the finite field GF(2) rather than using real numbers. The rank-width of a graph is the maximum of the ranks of the biadjacency matrices, for a clustering chosen to minimize this maximum.
Rank-width is closely related to clique-width: , where is the clique-width. However, clique-width is NP-hard to compute, for graphs of large clique-width, and its parameterized complexity is unknown. In contrast, testing whether the rank-width is at most a constant takes polynomial time, and even when the rank-width is not constant it can be approximated, with a constant approximation ratio, in polynomial time. For this reason, rank-width can be used as a more easily computed substitute for clique-width.
An example of a family of graphs with high rank-width is provided by the square grid graphs. For an grid graph, the rank-width is exactly .
References
Graph minor theory
Linear algebra |
https://en.wikipedia.org/wiki/Barry%20Dwolatzky | Barry Dwolatzky (29 April 1952 – 16 May 2023) was a South African software engineer. He was a professor emeritus at the University of the Witwatersrand Joburg Centre for Software Engineering. Dwolatzky was on University of the People's computer science advisory board. He was an anti-apartheid activist and in the late 1980s he joined the African National Congress's armed wing, Umkhonto we Sizwe ("spear of the nation").
Education
Dwolatzky completed a Bachelors of Science degree in 1975 and a Ph.D. in 1979, both in electrical engineering at the University of the Witwatersrand. He was a postdoctoral researcher at the University of Manchester Institute of Science and Technology and GEC Marconi.
Career
In 1989, Dwolatzky joined University of the Witwatersrand as a senior lecturer, becoming a full professor in 2000. He was an emeritus professor at the Joburg Centre for Software Engineering. Dwolatzky was on University of the People's computer science advisory board.
Dwolatzky was a fellow of the South African Institute of Electrical Engineers and The Institute of IT Professionals South Africa (IITPSA).
Death
Dwolatzky died in Johannesburg on 16 May 2023, at the age of 71.
References
External links
1950s births
Year of birth uncertain
2023 deaths
Place of birth missing
20th-century South African engineers
South African electrical engineers
Software engineers
21st-century South African engineers
University of the Witwatersrand alumni
Academic staff of the University of the Witwatersrand
University of the People people
South African computer programmers
White South African anti-apartheid activists |
https://en.wikipedia.org/wiki/Sheldon%20spectrum | The Sheldon spectrum is an empirically-observed feature of marine life by which the size of an organism is inversely correlated with its abundance in the ocean. The spectrum is named after Ray Sheldon, a marine ecologist at Canada’s Bedford Institute of Oceanography in Dartmouth, Nova Scotia. Sheldon and colleagues first suggested the existence of the inverse correlation based on seagoing measurements of plankton made with a Coulter counter in the late 1960s, most notably during the first circum-navigation of the Americas aboard the CCGS Hudson.
The inverse correlation implies that biomass density as a function of logarithmic body mass is approximately constant over many orders of magnitude. For example, when Sheldon and his colleagues analyzed a plankton sample in a bucket of seawater, they would tend to find that one third of the plankton mass was between 1 and 10 micrometers, another third was between 10 and 100 micrometers, and a third was between 100 micrometers and 1 millimeter. To make up for the differences of size, there must be a remarkably accurate mathematically correlative decrease in number of organisms as they become larger, in order for the biomass to remain constant. Thus, the rule predicts that krill which are a million times smaller than tuna are a million times more abundant in the ocean, a prediction which appears to be true.
There is strong evidence that human behavior, particularly overfishing and whaling, have modified the Sheldon spectrum for larger species, and it is unknown what long term effects such global alteration may have.
References
Marine organisms
Planktology
Marine biology |
https://en.wikipedia.org/wiki/Hydrocarbonoclastic%20bacteria | Hydrocarbonoclastic bacteria (also known as hydrocarbon degrading bacteria, oil degrading bacteria or HCB) are a heterogeneous group of prokaryotes which can degrade and utilize hydrocarbon compounds as source of carbon and energy. Despite being present in most of environments around the world, several of these specialized bacteria live in the sea and have been isolated from polluted seawater.
Taxonomy and distribution
The taxonomic diversity of hydrocarbon-degrading bacteria has not changed dramatically if we consider the higher taxa, many studies have provided information on 25 kinds of hydrocarbon-degrading bacteria and 25 kinds of fungi isolated from marine environments. Bacterial genera such as Gordonia, Brevibacterium, Aeromicrobium, Dietzia, Burkholderia and Mycobacterium isolated from oil have been shown to be potential organisms for hydrocarbon degradation. Cerniglia et al. observed that nine cyanobacteria, five green algae, one red alga, one brown alga and two diatoms could oxidise naphthalene. Temperature is crucial because it influences microbial physiology and diversity; the rate of biodegradation generally decreases as the temperature decreases.
Hydrocarbonoclastic bacteria are diazophilic, i.e. they can live in environments extremely poor in nitrogen compounds, which allows them to distribute themselves throughout the environment. They are extremely useful for environmentally friendly biosanitation; the fastest and most complete degradation occurs under aerobic conditions.
Hydrocarbons occur in marine environments where there are oil spills, which makes us understand that they are nutritionally independent of nitrogen sources, a characteristic due to their ability to fix atmospheric nitrogen. In Lagos in a city in Nigeria, nine bacterial strains Pseudomonas fluorescens, P. aeruginosa, Bacillus subtilis, Bacillus sp., Alcaligenes sp., Acinetobacter lwoffi, Flavobacterium sp., Micrococcus roseus and Corynebacterium sp, isolated from the polluted fl |
https://en.wikipedia.org/wiki/Aaron%20Robertson%20%28mathematician%29 | Aaron Robertson (born November 8, 1971) is an American mathematician who specializes in Ramsey theory. He is a professor at Colgate University.
Life and education
Aaron Robertson was born in Torrance, California, and moved with his parents to Midland, Michigan at the age of 4. He studied actuarial science as an undergraduate at the University of Michigan, and went on to graduate school in mathematics at Temple University in Philadelphia, where he was supervised by Doron Zeilberger. Robertson received his Ph.D. in 1999 with his thesis titled Some New Results in Ramsey Theory.
Following his Ph.D., Robertson became an assistant professor of mathematics at Colgate University, where he is currently a full professor.
Mathematical work
Robertson's work in mathematics since 1998 has consisted predominantly of topics related to Ramsey theory.
One of Robertson's earliest publications is a paper, co-authored with his supervisor Doron Zeilberger, which came out of his Ph.D. work. The authors prove that "the minimum number (asymptotically) of monochromatic Schur Triples that a 2-colouring of can have ".
After completing his dissertation, Robertson worked with 3-term arithmetic progressions where he found the best-known values that were close to each other and titled this piece New Lower Bounds for Some Multicolored Ramsey Numbers.
Another notable piece of Robertson's research is a paper co-authored with Doron Zeilberger and Herbert Wilf titled Permutation Patterns and Continued Fractions. In the paper, they "find a generating function for the number of (132)-avoiding permutations that have a given number of (123) patterns" with the result being "in the form of a continued fraction". Robertson's contribution to this specific paper includes discussion on permutations that avoid a certain pattern but contain others.
A notable paper Robertson wrote titled A Probalistic Threshold For Monochromatic Arithmetic Progressions explores the function (where is fixed) and the r-c |
https://en.wikipedia.org/wiki/Flag%20algebra | Flag algebras are an important computational tool in the field of graph theory which have a wide range of applications in homomorphism density and related topics. Roughly, they formalize the notion of adding and multiplying homomorphism densities and set up a framework to solve graph homomorphism inequalities with computers by reducing them to semidefinite programming problems. Originally introduced by Alexander Razborov in a 2007 paper, the method has since come to solve numerous difficult, previously unresolved graph theoretic questions. These include the question regarding the region of feasible edge density, triangle density pairs and the maximum number of pentagons in triangle free graphs.
Motivation
The motivation of the theory of flag algebras is credited to John Adrian Bondy and his work on the Caccetta-Haggkvist conjecture, where he illustrated his main ideas via a graph homomorphism flavored proof to Mantel's Theorem. This proof is an adaptation on the traditional proof of Mantel via double counting, except phrased in terms of graph homomorphism densities and shows how much information can be encoded with just density relationships.
Theorem (Mantel): The edge density in a triangle-free graph is at most . In other words,
As the graph is triangle-free, among 3 vertices in , they can either form an independent set, a single induced edge , or a path of length 2 . Denoting as the induced density of a subgraph in , double counting gives:
Intuitively, since a just consists of two s connected together, and there are 3 ways to label the common vertex among a set of 3 points. In fact, this can be rigorously proven by double counting the number of induced s. Letting denote the number of vertices of , we have:
where is the path of length 2 with its middle vertex labeled, and represents the density of s subject to the constraint that the labeled vertex is used, and that is counted as a proper induced subgraph only when its labeled vertex coincides with . |
https://en.wikipedia.org/wiki/Cytosis%20%28board%20game%29 | Cytosis is a cell biology worker placement board game designed by John Coveyou and published in 2017 by Genius Games. The game's development was funded via a crowdfunding campaign on Kickstarter.
Gameplay
The objective of the game is to ensure the health of a human cell by managing its operations. The board represents a cell in which are located various organelles that are sites of player actions. Around the edge of the board is a scoring track. There are coloured cubes representing various macromolecules within the cell: carbohydrates (green), lipids (yellow), messenger RNA (mRNA, black), and proteins (red). The sets of cards are split into Cell Component cards, Event cards, and Goal cards.
The cards are separated by type and shuffled, then four Cell Component cards are placed on the appropriate area of the game board, three to five randomly selected Goal cards are placed at the top of the game board, and players place one of their tokens at the zero space of the scoring track. The starting player receives two adenosine triphosphate (ATP) tokens, and each subsequent player one more ATP token than the player preceding them. Each player also selects to keep one of the three Cell Component cards that were dealt to them, shuffling the others into the draw pile.
Each turn, a player places their flask token on a chosen organelle and executes the prescribed action. These actions enable the player to collect resources such as carbohydrates or ATP, or to acquire Cell Component cards. This requires multiple steps and multiple turns to simulate the process of protein synthesis.
Players acquire health points by completing the actions listed on Cell Component cards, such as assembling enzymes and hormones or hormone receptors. These are then deployed to defend the cell from viral infection. Health points are the game's victory points.
Expansion
The Virus expansion set includes additional Cell Component, Event, and Goal cards, and also includes pink antibody cubes, dice, an |
https://en.wikipedia.org/wiki/Hypergraph%20regularity%20method | In mathematics, the hypergraph regularity method is a powerful tool in extremal graph theory that refers to the combined application of the hypergraph regularity lemma and the associated counting lemma. It is a generalization of the graph regularity method, which refers to the use of Szemerédi's regularity and counting lemmas.
Very informally, the hypergraph regularity lemma decomposes any given -uniform hypergraph into a random-like object with bounded parts (with an appropriate boundedness and randomness notions) that is usually easier to work with. On the other hand, the hypergraph counting lemma estimates the number of hypergraphs of a given isomorphism class in some collections of the random-like parts. This is an extension of Szemerédi's regularity lemma that partitions any given graph into bounded number parts such that edges between the parts behave almost randomly. Similarly, the hypergraph counting lemma is a generalization of the graph counting lemma that estimates number of copies of a fixed graph as a subgraph of a larger graph.
There are several distinct formulations of the method, all of which imply the hypergraph removal lemma and a number of other powerful results, such as Szemerédi's theorem, as well as some of its multidimensional extensions. The following formulations are due to V. Rödl, B. Nagle, J. Skokan, M. Schacht, and Y. Kohayakawa, for alternative versions see Tao (2006), and Gowers (2007).
Definitions
In order to state the hypergraph regularity and counting lemmas formally, we need to define several rather technical terms to formalize appropriate notions of pseudo-randomness (random-likeness) and boundedness, as well as to describe the random-like blocks and partitions.
Notation
denotes a -uniform clique on vertices.
is an -partite -graph on vertex partition .
is the family of all -element vertex sets that span the clique in . In particular, is a complete -partite -graph.
The following defines an important notion of relat |
https://en.wikipedia.org/wiki/Guacolda%20Antoine%20Lazzerini | Guacolda Antoine Lazzerini (11 April 1908 – 22 August 2015) was a Chilean mathematician and teacher of mathematics.
Education and career
Antoine's father died when Antoine was a teenager, and she began helping to support the family by teaching mathematics. She entered the teaching school of the University of Chile in 1924, and finished her studies there in 1928, earning the title of professor of mathematics and physics with a thesis on differential equations and their application in pedagogy and engineering. She became a high school mathematics teacher at the Liceo José Victorino Lastarria (Santiago), and continued to teach there for the next 30 years.
Meanwhile, she also became a professor at the from 1928 to 1931, earning a credential as an actuary there in 1929. In 1933 she became an assistant professor at the University of Chile, and by 1954 she was promoted to full professor there. She was named a professor in Chile's school for industrial engineers in 1947, which in 1953 merged into the (UTE). She also helped found The Kent School, a private school in Santiago, in 1953. From 1958 to 1962 she held a position at the UTE equivalent to that of a dean, the first woman at that level in UTE, and from 1963 to 1968 she was head of the mathematics department in the faculty of philosophy and education at the University of Chile. In the 1950s and 1960s she also represented Chile in several international events concerning mathematics teaching. She retired in 1985, but remained active in mathematics long afterward.
Book
In 1971, Antoine coauthored the book Nuevas Matematicas Para Los Padres [New Mathematics for Parents], with María Lara. It concerned New Math and set theory, subjects popular in mathematics education at the time.
Personal life
Antoine was born on 11 April 1908 in Santiago, one of seven children in a family of immigrants; her mother was from Italy and her father from France, both emigrating to Chile as children in the occupation of Araucanía of the late |
https://en.wikipedia.org/wiki/Quasirandom%20group | In mathematics, a quasirandom group is a group that does not contain a large product-free subset. Such groups are precisely those without a small non-trivial irreducible representation. The namesake of these groups stems from their connection to graph theory: bipartite Cayley graphs over any subset of a quasirandom group are always bipartite quasirandom graphs.
Motivation
The notion of quasirandom groups arises when considering subsets of groups for which no two elements in the subset have a product in the subset; such subsets are termed product-free. László Babai and Vera Sós asked about the existence of a constant for which every finite group with order has a product-free subset with size at least . A well-known result of Paul Erdős about sum-free sets of integers can be used to prove that suffices for abelian groups, but it turns out that such a constant does not exist for non-abelian groups.
Both non-trivial lower and upper bounds are now known for the size of the largest product-free subset of a group with order . A lower bound of can be proved by taking a large subset of a union of sufficiently many cosets, and an upper bound of is given by considering the projective special linear group for any prime . In the process of proving the upper bound, Timothy Gowers defined the notion of a quasirandom group to encapsulate the product-free condition and proved equivalences involving quasirandomness in graph theory.
Graph quasirandomness
Formally, it does not make sense to talk about whether or not a single group is quasirandom. The strict definition of quasirandomness will apply to sequences of groups, but first bipartite graph quasirandomness must be defined. The motivation for considering sequences of groups stems from its connections with graphons, which are defined as limits of graphs in a certain sense.
Fix a real number A sequence of bipartite graphs (here is allowed to skip integers as long as tends to infinity) with having vertices, vert |
https://en.wikipedia.org/wiki/Pronunciation%20of%20GIF | The pronunciation of GIF, an acronym for the Graphics Interchange Format, has been disputed since the 1990s. Popularly rendered in English as a one-syllable word, the acronym is most commonly pronounced (with a hard g as in gift) or (with a soft g as in gem), differing in the phoneme represented by the letter G. Many public figures and institutions have taken sides in the debate; Steve Wilhite, the creator of the image file format, gave a speech at the 2013 Webby Awards arguing for the soft-g pronunciation. Others have pointed to the term's origin from abbreviation of the hard-g word graphics to argue for the other pronunciation.
The controversy stems partly from the fact that there is no general rule for how the letter sequence gi is to be pronounced; the hard g prevails in words such as gift, while the soft g is used in others such as ginger. In addition, some speakers enunciate each letter in the acronym, producing . English dictionaries generally accept both main alternatives as valid, and linguistic analyses show no clear advantage for either based on the pronunciation frequencies of similar English words. The pronunciation of the acronym can also vary in languages other than English.
Background
The Graphics Interchange Format (GIF) is an image file format developed in 1987 by Steve Wilhite at the American online service provider CompuServe. GIFs are popularly used to display short, looped animations. The acronym GIF, commonly pronounced as a monosyllable, has a disputed pronunciation. Some individuals pronounce the word with a hard g, as in , whereas others pronounce it with a soft g, as in . A minority prefer to enunciate each letter of the acronym individually, creating the pronunciation .
Wilhite and the team who developed the file format included in the technical specifications that the acronym was to be pronounced with a soft g. In the specifications, the team wrote that "choosy programmers choose ... 'jif, in homage to the peanut butter company Jif' |
https://en.wikipedia.org/wiki/Polyhedral%20map%20projection | A polyhedral map projection is a map projection based on a spherical polyhedron. Typically, the polyhedron is overlaid on the globe, and each face of the polyhedron is transformed to a polygon or other shape in the plane. The best-known polyhedral map projection is Buckminster Fuller's Dymaxion map. When the spherical polyhedron faces are transformed to the faces of an ordinary polyhedron instead of laid flat in a plane, the result is a polyhedral globe.
Often the polyhedron used is a Platonic solid or Archimedean solid. However, other polyhedra can be used: the AuthaGraph projection makes use of a polyhedron with 96 faces, and the myriahedral projection allows for an arbitrary large number of faces.
Although interruptions between faces are common, and more common with an increasing number of faces, some maps avoid them: the Lee conformal projection only has interruptions at its border, and the AuthaGraph projection scales its faces so that the map fills a rectangle without internal interruptions. Some projections can be tesselated to fill the plane, the Lee conformal projection among them.
To a degree, the polyhedron and the projection used to transform each face of the polyhedron can be considered separately, and some projections can be applied to differently shaped faces. The gnomonic projection transforms the edges of spherical polyhedra to straight lines, preserving all polyhedra contained within a hemisphere, so it is a common choice. The Snyder equal-area projection can be applied to any polyhedron with regular faces. The projection used in later versions of the Dymaxion map can be generalized to other equilateral triangular faces, and even to certain quadrilaterals.
Polyhedral map projections are useful for creating discrete global grids, as with the quadrilateralized spherical cube and Icosahedral Snyder Equal Area (ISEA) grids.
History
The earliest known polyhedral projection is the octant projection developed by Leonardo da Vinci or his associate aro |
https://en.wikipedia.org/wiki/Neuroecology | Neuroecology studies ways in which the structure and function of the brain results from adaptations to a specific habitat and niche.
It integrates the multiple disciplines of neuroscience, which examines the biological basis of cognitive and emotional processes, such as perception, memory, and decision-making, with the field of ecology, which studies the relationship between living organisms and their physical environment.
In biology, the term 'adaptation' signifies the way evolutionary processes enhance an organism's fitness to survive within a specific ecological context. This fitness includes the development of physical, cognitive, and emotional adaptations specifically suited to the environmental conditions in which the organism or phenotype lives, and in which its species or genotype evolves.
Neuroecology concentrates specifically on neurological adaptations, particularly those of the brain. The purview of this study encompasses two areas. Firstly, neuroecology studies how the physical structure and functional activity of neural networks in a phenotype is influenced by characteristics of the environmental context. This includes the way social stressors, interpersonal relationships, and physical conditions precipitate persistent alterations in the individual brain, providing the neural correlates of cognitive and emotional responses. Secondly, neuroecology studies how neural structure and activity common to a genotype is determined by natural selection of traits that benefit survival and reproduction in a specific environment.
See also
Evolutionary ecology
Evolutionary psychology
References
External links
Cognitive Neuroecology Lab at the FMRIB Centre of the University of Oxford (UK) and Donders Institute in Nijmegen (Netherlands)
Behavioral neuroscience
Evolutionary biology
Ecology terminology
Ecology |
https://en.wikipedia.org/wiki/Defence%20Secretariat%2019 | Defence Secretariat 19 (DS19) was a special unit set up within the British Ministry of Defence by Michael Heseltine in March 1983. Its purpose was to combat the Campaign for Nuclear Disarmament (CND) and all calls for unilateral nuclear disarmament.
References
See also
Women and Families for Defence
Ministry of Defence (United Kingdom)
Politics of the United Kingdom
Cold War
Nuclear organizations
Anti–nuclear weapons movement |
https://en.wikipedia.org/wiki/Georges%20A.%20Deschamps | Georges Armand Deschamps (October 18, 1911 — June 20, 1998) was a French American engineer and Professor Emeritus at the Department of Electrical Engineering at University of Illinois at Urbana-Champaign. He is best known for his contributions to electromagnetic theory, microwave engineering and antenna theory. He is also regarded as an early pioneer of microstrip and patch antennas, which he proposed in 1953.
Biography
Born on October 18, 1911, in Vendôme, France, Deschamps was raised in Normandy. He was admitted to École normale supérieure in Paris in 1931, where he studied mathematics and was a classmate of Georges Pompidou, former President of France. He further received advanced degrees in physics and mathematics from University of Paris, Sorbonne. Initially planning to study topology with Eduard Čech at Masaryk University, he eventually went to Princeton University as a research associate for a year in 1937. Following this, he taught mathematics and physics at Lycée Français de New York. In the meantime, with the advent of World War II, he was enlisted to French Army and worked as an engineer for Maginot Line. Following the Battle of France in 1940, he escaped through North Africa and returned to the United States in 1941 to resume his teaching duties.
In 1947, Deschamps joined Federal Telecommunications Laboratories of ITT Inc. as a project engineer, where he worked on radio navigation and antenna design. In 1958, he joined University of Illinois at Urbana-Champaign as the director of the Antenna Laboratory, following the departure of the previous director, Victor H. Rumsey. The research work of the laboratory during this period focused on frequency independent antennas. In 1978, he was elected to the National Academy of Engineering for "his contributions to electromagnetic scattering, microwave engineering, and laser beam propagation." Being a Life Fellow of IEEE, he was a recipient of IEEE Centennial Medal (1984) and IEEE Antennas and Propagation Society |
https://en.wikipedia.org/wiki/Engineering%20information%20management | Engineering information management (EIM) is the business function within product development and specifically systems engineering that allows engineers to collaborate on a single source of truth of engineering data.
Contrary to product data management (PDM) and product lifecycle management (PLM), its main purpose is not storage of CAD-related drawings and files, but rather the full execution of the V-model for hardware development, complementing and integrating to the above mentioned systems.
Scope
EIM systems enable collaboration on all important aspects of the engineering lifecycle, such as:
Requirements management
Functional design
Product architecture
Detailed systems design and simulation
Verification and validation
Documentation
EIM systems implement the activities on both sides of the engineering V-model. Instead of being purely a data storage, it focuses also on the human interaction with the models and data, thus enabling concurrent engineering.
EIM therefore enables the optimization of products and engineering processes, where traditional methodologies have become ineffective in keeping up with rising product and process complexity.
Interactions with the other engineering management systems
EIM systems do directly and indirectly interact with other tools in the engineering information infrastructure, such as:
Computer simulation tools
Automated hardware testing tools
Product lifecycle and product data management systems
Enterprise resource planning tools
Manufacturing execution systems
Computer-aided design (MCAD) and electronic design automation (ECAD) tools
References
Product development
Systems engineering
Information management |
https://en.wikipedia.org/wiki/Buy%20now%2C%20pay%20later | Buy now, pay later (BNPL) is a type of short-term financing that allows consumers to make purchases and pay for them at a future date. BNPL is generally structured like an installment plan money lending process that involves consumers, financiers, and merchants. Financiers pay merchants on behalf of the consumers when goods or services are purchased by the latter. These payments are later repaid by the consumers over time in equal installments. The number of installments and repayment period varies depending on the BNPL financiers.
History
The earliest form of BNPL traces back to the 19th century, when installment plans emerged as a way for consumers to purchase expensive goods (e.g. furniture, pianos and farm equipment) they did not have the funds to buy outright. In India, BNPL is considered similar to the country's traditional paper-based Udhar Khata system, where corner shops, known as kiranas locally, kept manually logged credit ledgers to allow their customers to buy provisions on credit and repay them later.
In the early 21st century, fintech companies developed systems that allowed installment plan lending to be integrated into the payment flow of online shops, allowing a consumer to receive instant credit at the point of sale and pay for a purchase later, based on an agreed schedule. The integration and instant processing elements are what sets BNPL apart from other approaches to consumer lending.
Usage
BNPL has been described as "similar to a credit card but without the hassles of an application process, card-swiping infrastructure, and separate limits for purchases and cash withdrawals". Retailers that partner with BNPL financiers can offer customers the option to pay for purchases using BNPL. If a customer opts to complete the purchase using BNPL, the financier will typically carry out a soft credit check on the customer, and return a decision within seconds. The financier pays the merchant if approval is received, and offers the customer various repa |
https://en.wikipedia.org/wiki/Germ-Soma%20Differentiation | Germ-Soma Differentiation is the process by which organisms develop distinct germline and somatic cells. The development of cell differentiation has been one of the critical aspects of the evolution of multicellularity and sexual reproduction in organisms. Multicellularity has evolved upwards of 25 times, and due to this there is great possibility that multiple factors have shaped the differentiation of cells. There are three general types of cells: germ cells, somatic cells, and stem cells. Germ cells lead to the production of gametes, while somatic cells perform all other functions within the body. Within the broad category of somatic cells, there is further specialization as cells become specified to certain tissues and functions. In addition, stem cell are undifferentiated cells which can develop into a specialized cell and are the earliest type of cell in a cell lineage. Due to the differentiation in function, somatic cells are found ony in multicellular organisms, as in unicellular ones the purposes of somatic and germ cells are consolidated in one cell.
All organisms with germ-soma differentiation are eukaryotic, and represent an added level of specialization to multicellular organisms. Pure germ-soma differentiation has developed in a select number of eukaryotes (called Weismannists), included in this category are vertebrates and arthropods- however land plants, green algae, red algae, brown algae, and fungi have partial differentiation. While a significant portion of organisms with germ-soma differentiation are asexual, this distinction has been imperative in the development of sexual reproduction; the specialization of certain cells into germ cells is fundamental for meiosis and recombination.
Weismann barrier
The strict division between somatic and germ cells is called the Weismann barrier, in which genetic information passed onto offspring is found only in germ cells. This occurs only in select organisms, however some without a Weismann barrier do pre |
https://en.wikipedia.org/wiki/Friederike%20Mengel | Friederike Mengel (born March 27, 1979) is a German economist who is a Professor of economics at the University of Essex.
Education and career
Friederike Mengel earned an undergraduate degree in economics from the University of Mainz in 2003, followed by a PhD in economics from the University of Alicante in 2008, under the supervision of Fernando Vega Redondo. After her PhD, she joined Maastricht University where she was an Assistant Professor from 2008 to 2011 and an Associate Professor from 2011 to 2013. After a period at the University of Nottingham, she joined the University of Essex in 2012 where she has been a Professor since 2015. In 2019 she received the Philipp Leverhulme Prize in Economics.
Research
Mengel's research areas are (Evolutionary) Game Theory, Learning, Behavioral Economics, Social Networks and Experimental Economics. She developed a theory of learning across games, where agents might partition a set of all games into categories. Learning across games can destabilize strict Nash equilibria even for arbitrarily small reasoning costs and even if players distinguish all the games at the stable point. The model is also able to explain a number of experimental findings.
Mengel has also done work on social identity and on how people learn in social networks. Her work uncovered that people pay attention to others network position when learning, but only partially and they do not update in a Bayesian way. Their work with J. Kovarik and J. Romero was awarded the Best Paper Award by the Econometric Society in 2019.
Selected publications
Drago, F., F. Mengel and C. Traxler (2020): Compliance Behavior in Networks: Evidence from a Field Experiment, American Economic Journal: Applied Economics 12(2), 1–40.
Grimm, V. and F. Mengel (2020): Experiments on Belief Formation in Networks, Journal of the European Economic Association 18(1), 49-82.
Kovarik, J., F. Mengel and J. G. Romero (2018): Learning in Network Games, Quantitative Economics 9(1), 85–139.
G |
https://en.wikipedia.org/wiki/RealCall | RealCall is a US-based AI caller identification and call blocking smartphone application, used to detect, engage and block call and SMS scamming and spamming. It has AI algorithms with built-in free reverse phone lookup service and customized answer bots for detection, engagement and blocking of unwanted calls and messages. The app is available for Android and iOS devices.
Overview
RealCall is a US based AI smartphone application, to detect, engage and block spam calls, with a database of known numbers and an AI algorithm to identify phone numbers and block calls from robocallers, spammers, telemarketers and scammers. It analyze caller's voice and call's content to determine the nature of a call. The app auto block unwanted calls, and use answer bots to answer calls from telemarketers. It has reverse lookup service, used to find owner name, address, network carrier, location, risk level of unknown numbers, and system integrated with FTC Do Not Call Registry.
History
RealCall is developed by Second Phone Number Inc., a privately held company with a head office in San Jose, California, US. It released first iOS version of the app on 6 April 2022, and Android version in December 2022. As of September 2022, it has blocked 30.63 million spam calls and 11.6 billion spam text messages, originating mainly from 530, 502, 626, 915, and 315 US area codes. In November 2022, Dingtone announced partnership with RealCall and integrated its API. As of 2022, It has collected 1.5 billion phone numbers in its global database.
Availability
The app is only available in US and Canada, for iOS and Android users.
See also
Truecaller
CallApp
References
External links
www.realcall.ai
Caller ID
Spam filtering
Mobile software
Android (operating system) software
IOS software
Social networking services |
https://en.wikipedia.org/wiki/Barrelfish%20%28operating%20system%29 | Barrelfish is an experimental computer operating system built by ETH Zurich with the assistance of Microsoft Research in Cambridge. It is an experimental operating system designed from the ground up for scalability for computers built with multi-core processors with the goal of reducing the compounding decrease in benefit as more CPUs are used in a computer via putting low level hardware information in a database, removing the necessity for driver software.
The partners released the first snapshot of the OS on September 15, 2009 with a second being released in March, 2011. Excluding some third-party libraries, which are covered by various BSD-like open source licenses, Barrelfish is released under the MIT license. Snapshots are regularly released, the last one dating to March 23, 2020.
While originally being developed in collaboration with Microsoft Research, it is now partly supported by Hewlett Packard Enterprise Labs, Huawei, Cisco, Oracle, and VMware.
See also
Singularity
Midori
References
Further reading
External links
Barrelfish.org
Project Paper - "The Multikernel: A new OS architecture for scalable multicore systems" (PDF file)
Free software
Distributed operating systems
Microkernel-based operating systems
Microkernels
Microsoft free software
Microsoft operating systems
Microsoft Research
Software using the MIT license
2009 software |
https://en.wikipedia.org/wiki/Congresstrading.com | Congresstrading.com is a commercial website that provides access to a database of financial disclosures of members of the United States Congress. It also provides a forum to discuss Congress' stock trades, according to WXII 12, an NBC affiliate news station. Congress is required to publicly disclose their financial transactions by the STOCK Act.
History
Since its founding in October 2020, congresstrading.com has been credited by various news organizations for providing and disclosing information related to financial transactions by members of Congress. In January 2021, the New York Times reported that Speaker Nancy Pelosi purchased Tesla stock options based on information sourced from congresstrading.com. In October 2021 CNBC, CNN, and the Washington Post reported that Congresswoman Marjorie Taylor Greene bought shares of Trump SPAC Digital World Acquisition Corp based on information provided by congresstrading.com.
References
External links
2020 establishments in the United States
Legislative branch of the United States government
Insider trading
American websites
Internet properties established in 2020
Online databases |
https://en.wikipedia.org/wiki/Arginylation | Arginylation is a post-translational modification in which proteins are modified by the addition of arginine (Arg) at the N-terminal amino group or side chains of reactive amino acids by the enzyme, arginyltransferase (ATE1). Recent studies have also revealed that hundreds of proteins in vivo are arginylated, proteins which are essential for many biological pathways. While still poorly understood in a biological setting, the ATE1 enzyme is highly conserved which suggests that arginylation is an important biological post-translational modification.
Examples of ATE1 targets which have been identified include ornithine decarboxylase., thyroglobulin, insulin, and neurotensin.
Discovery
In 1963, a group of researchers observed that specific radioactive amino acids were being incorporated into proteins obtained from ribosome-free cell and tissue extracts. This incorporation of amino acids into ribosome-lacking cells was first observed in prokaryotes using leucine (Leu) and phenylalanine (Phe), and was further discovered in mammalian liver extracts using arginine. The incorporation of other amino acids into ribosome-lacking cells failed to yield similar results, suggesting that the mechanism was specific to leucine and phenylalanine in bacteria and arginine in mammals. One of the most interesting aspects of arginylation is that the amino acids used for arginylation are transferred from aminoacyl tRNAs onto the target protein, without the use of any other translational components. This way of modifying proteins post-translationally does not occur in any other amino acid addition to proteins, such as in glycylation, glutamylation, and tyrosination making arginylation truly unique.
Upon discovery of this modification and its mechanism, further research was performed to identify an enzyme or enzymes which promote this modification. After identifying the enzyme responsible for this modification in both plants and guinea-pig hair follicles, it was cloned and characteriz |
https://en.wikipedia.org/wiki/CAST-15 | CAST-15, Merging High-Level and Low-Level Requirements is a Certification Authorities Software Team (CAST) Position Paper. It is an FAA publication that "does not constitute official policy or guidance from any of the authorities", but is provided to applicants for software and hardware certification for educational and informational purposes only.
As established by the FAA advisory circular AC 20-115, the RTCA publication DO-178B/C defines an acceptable means of certification of airworthy software. Unique among development standards, DO-178B introduced a distinction between High-Level Requirements and Low-Level Requirements as formal products of software requirements analysis and design when developing airworthy software.
DO-17B/C assigned different sets of objectives to these two levels of requirements. To accomplish compliance, the Applicant needs to fulfill both sets of objectives with their requirements. However, under narrow conditions, that standard's guidance permits combination of these two levels into just one level of requirements, but warns against the practice in general.
This position paper is concerned with observed misuse of this guidance; some applicants were combining High-Level and Low-Level Requirements for "simple" products, but were not accomplishing all of the related objectives for both levels of requirements.
This position paper is also an example of Certification Authorities using their "what" versus "how" distinction between high-level and low-level requirements that DO-178B/C does not clearly explain.
Background
Various stakeholders for software definition and verification have differing objectives and levels of abstraction. Those stakeholders responsible for defining or verifying high-level software product functionality are generally concerned with the structures and behaviors of the product's external interfaces, and details of internal software structures do not necessarily support that focus. On the other hand, those responsi |
https://en.wikipedia.org/wiki/Deep%20learning%20speech%20synthesis | Deep learning speech synthesis uses Deep Neural Networks (DNN) to produce
artificial speech from text (text-to-speech) or spectrum (vocoder).
The deep neural networks are trained using a large amount of recorded speech and, in the case of
a text-to-speech system, the associated labels and/or input text.
Some DNN-based speech synthesizers are approaching the naturalness of the human voice.
Formulation
Given an input text or some sequence of linguistic unit , the target speech can be derived by
where is the model parameter.
Typically, the input text will first be passed to an acoustic feature generator, then the acoustic features are passed to the neural vocoder. For the acoustic feature generator, the Loss function is typically L1 or L2 loss. These loss functions impose a constraint that the output acoustic feature distributions must be Gaussian or Laplacian. In practice, since the human voice band ranges from approximately 300 to 4000 Hz, the loss function will be designed to have more penalty on this range:
where is the loss from human voice band and is a scalar typically around 0.5. The acoustic feature is typically Spectrogram or spectrogram in Mel scale. These features capture the time-frequency relation of speech signal and thus, it is sufficient to generate intelligent outputs with these acoustic features. The Mel-frequency cepstrum feature used in the speech recognition task is not suitable for speech synthesis because it reduces too much information.
Brief history
In September 2016, DeepMind proposed WaveNet, a deep generative model of raw audio waveforms, demonstrating that deep learning-based models are capable of modeling raw waveforms and generating speech from acoustic features like spectrograms or mel-spectrograms. Although WaveNet was initially considered to be computationally expensive and slow to be used in consumer products at the time, a year after its release, DeepMind unveiled a modified version of WaveNet known as "Parallel WaveNet |
https://en.wikipedia.org/wiki/Genetically%20modified%20agriculture | Genetically modified agriculture includes:
Genetically modified crops
Genetically modified livestock
Genetic engineering
Genetically modified organisms |
https://en.wikipedia.org/wiki/Curvature%20of%20Space%20and%20Time%2C%20with%20an%20Introduction%20to%20Geometric%20Analysis | Curvature of Space and Time, with an Introduction to Geometric Analysis is an undergraduate-level textbook for mathematics and physics students on differential geometry, focusing on applications to general relativity. It was written by Iva Stavrov, based on a course she taught at the 2013 Park City Mathematics Institute and subsequently at Lewis & Clark College, and was published in 2020 by the American Mathematical Society, as part of their Student Mathematical Library book series.
Topics
Curvature of Space and Time is arranged into five chapters with 14 sections in total, with each section covering a single lecture's worth of material. Its topics are covered both mathematically and historically, with reference to the original source material of Bernhard Riemann and others. However, it deliberately avoids some topics from differential topology that have traditionally been covered in differential geometry courses, including abstract manifolds and tangent vectors. Instead, it approaches the subject through coordinate-based geometry, emphasizing quantities that are invariant under changes of coordinates. Its goals include both providing a shortened path for students to reach an understanding of Einstein's mathematics, and promoting curvature as a central way of describing shape and geometry.
The first chapter defines Riemannian manifolds as embedded subsets of Euclidean spaces rather than as abstract spaces. It uses Christoffel symbols to formulate differential equations having the geodesics as their solutions, and descrobes the Koszul formula and energy functional Examples include the Euclidean metric, spherical geometry, projective geometry, and the Poincaré half-plane model of the hyperbolic plane. Chapter 2 includes vector fields, gradients, divergence, directional derivatives, tensor calculus, Lie brackets, Green's identities, the maximum principle, and the Levi-Civita connection. It begins a discussion of curvature and the Riemann curvature tensor that is con |
https://en.wikipedia.org/wiki/Insects%20in%20Japanese%20culture | Within Japanese culture, insects have occupied an important role as aesthetic, allegorical, and symbolic objects. In addition, insects have had a historical importance within the context of the culture and art of Japan.
Kenta Takada, longhorn beetle collector and author, noted that the Japanese appreciation for insects lies within the Shinto religion. Shinto, a form of animism, places emphasis that every facet of the natural world is worthy of reverence as they are the creation of the spiritual dimension. Takada additionally noted the importance of mono no aware, Zen awareness of the transience of all things, as an important factor within the perception of insects in a Japanese context. Lafcadio Hearn remarked that "[the] belief in a mysterious relation between ghosts and insects, or rather between spirits and insects, is a very ancient belief in the East".
Historical context
Insects have occupied a place within Japanese culture for centuries. The Lady who Loved Insects, is a classic tale of a woman who collected caterpillars during the 12th century. The Tamamushi Shrine, a miniature temple from the 7th century was formerly adorned with beetlewing from the jewel beetle Chrysochroa fulgidissima.
Lafcadio Hearn, a European-American scholar who became a Japanese citizen in the 19th century remarked: "In old Japanese literature, poems upon insects are to be found by thousands". Hearn's body of work while he was a citizen of Japan and as he analyzed Japanese literary works particularly focused on the comparative state of Western perceptions of insects compared to the Japanese ways of "[finding] delight, century after century, in watching the ways of insects". Twelve of the eleven books that Hearn had written included passages devoted to insects. In particular, Hearn wrote about Japanese tales regarding silkworms, cicadas, dragonflies, flies, kusa-hibari (a cricket known under the scientific name Svistella bifasciata), ants, fireflies, butterflies, and mosquitoes.
Ent |
https://en.wikipedia.org/wiki/TNet | TNet is a secure top-secret-level intranet system in the White House, notably used to record information about telephone and video calls between the President of the United States and other world leaders. TNet is connected to Joint Worldwide Intelligence Communications System (JWICS), which is used more widely across different offices in the White House. Contained within TNet is an even more secure system known as NSC Intelligence Collaboration Environment (NICE).
NSC Intelligence Collaboration Environment
The NSC Intelligence Collaboration Environment (NICE) is a computer system operated by the United States National Security Council's Directorate for Intelligence Programs. A subdomain of TNet, it was created to enable staff to produce and store documents, such as presidential findings or decision memos, on top secret codeword activities. Due to the extreme sensitivity of the material held on it, only about 20 percent of NSC staff can reportedly access the system. The documents held on the system are tightly controlled and only specific named staff are able to access files.
The system became the subject of controversy during the Trump–Ukraine scandal, when a whistleblower complaint to the Inspector General of the Intelligence Community revealed that NICE had been used to store transcripts of calls between President Donald Trump, and foreign leaders, apparently to restrict access to them. The system was reportedly used for this purpose from 2017 after leaks of conversations with foreign leaders. It was said to have been upgraded in the spring of 2018 to log, who had accessed particular files, as a deterrent against possible leaks.
See also
Classified website
Intellipedia
Joint Worldwide Intelligence Communications System (JWICS)
NIPRNet
RIPR
SIPRNet
References
Computer systems
United States National Security Council
Wide area networks
United States government secrecy |
https://en.wikipedia.org/wiki/Surplus%20sharing | Surplus sharing is a kind of a fair division problem where the goal is to share the financial benefits of cooperation (the "economic surplus") among the cooperating agents. As an example, suppose there are several workers such that each worker i, when working alone, can gain some amount ui. When they all cooperate in a joint venture, the total gain is u1+...+un+s, where s>0. This s is called the surplus of cooperation, and the question is: what is a fair way to divide s among the n agents?
When the only available information is the ui, there are two main solutions:
Equal sharing: each agent i gets ui+s/n, that is, each agent gets an equal share of the surplus.
Proportional sharing: each agent i gets ui+(s*ui/Σui), that is, each agent gets a share of the surplus proportional to his external value (similar to the proportional rule in bankruptcy). In other words, ui is considered a measure of the agent's contribution to the joint venture.
Kolm calls the equal sharing "leftist" and the proportional sharing "rightist".
Chun presents a characterization of the proportional rule.
Moulin presents a characterization of the equal and proportional rule together by four axioms (in fact, any three of these axioms are sufficient):
Separability - the division of surplus within any coalition T should depend only on the total amount allocated to T, and on the opportunity costs of agents within T.
No advantageous reallocation - no coalition can benefit from redistributing its ui among its members (this is a kind of strategyproofness axiom).
Additivity - for each agent i, the allocation to i is a linear function of the total surplus s.
Path independence - for each agent i, the allocation to i from surplus s is the same as allocating a part of s, updating the ui, and then allocating the remaining part of s.
Any pair of these axioms characterizes a different family of rules, which can be viewed as a compromise between equal and proportional sharing.
When there is informatio |
https://en.wikipedia.org/wiki/Children%27s%20Code | The Age appropriate design code, also known as the Children's Code, is a British internet safety and privacy code of practice created by the Information Commissioner's Office (ICO). The draft Code was published in April 2019, as instructed by the Data Protection Act 2018 (DPA). The final regulations were published on 27 January 2020 and took effect 2 September 2020, with a one-year grace period before the beginning of enforcement. The Children's Code is written to be consistent with GDPR and the DPA, meaning that compliance with the Code is enforceable under the latter.
It applies to any internet-connected product or service that is likely to be accessed by a person under the age of 18. It requires online services to be designed in the "best interests" of children and their health, safety, and privacy, requiring that they be afforded with the strongest privacy settings by default, that only data strictly necessary to deliver individual service elements is collected from children unless there is justification, and that children's personal data not be disclosed to third-parties unless there is justification. It also requires privacy policies and controls to be presented in a manner that is clear and accessible to children, including prohibiting dark patterns.
Contents
The Children's Code is a code of practice enforceable under the Data Protection Act 2018, and is consistent with GDPR and the Convention on the Rights of the Child. It specifies design standards for any information society services (ISS, which includes websites, software and apps, and connected toys) that are likely to be used by a person under the age of 18 and is based in or serves users within the United Kingdom.
The Code requires that services be designed in "the best interests" of children, including their physical and mental health, protecting them from being exploited commercially or sexually, and acknowledging parents and caregivers' roles in protecting and supporting their child's best inter |
https://en.wikipedia.org/wiki/Scandium%20phosphide | Scandium phosphide is an inorganic compound of scandium and phosphorus with the chemical formula .
Synthesis
ScP can be obtained by the reaction of scandium and phosphorus at 1000 °C.
4Sc + P4 -> 4ScP
Physical properties
This compound is calculated to be a semiconductor used in high power, high frequency applications and in laser diodes.
Chemical properties
ScP can be smelted with cobalt or nickel through electric arc to obtain ScCoP and ScNiP.
References
Phosphides
Scandium compounds
Semiconductors
Rock salt crystal structure |
https://en.wikipedia.org/wiki/Korkine%E2%80%93Zolotarev%20lattice%20basis%20reduction%20algorithm | The Korkine–Zolotarev (KZ) lattice basis reduction algorithm or Hermite–Korkine–Zolotarev (HKZ) algorithm is a lattice reduction algorithm.
For lattices in it yields a lattice basis with orthogonality defect at most , unlike the bound of the LLL reduction. KZ has exponential complexity versus the polynomial complexity of the LLL reduction algorithm, however it may still be preferred for solving multiple closest vector problems (CVPs) in the same lattice, where it can be more efficient.
History
The definition of a KZ-reduced basis was given by Aleksandr Korkin and Yegor Ivanovich Zolotarev in 1877, a strengthened version of Hermite reduction. The first algorithm for constructing a KZ-reduced basis was given in 1983 by Kannan.
The block Korkine-Zolotarev (BKZ) algorithm was introduced in 1987.
Definition
A KZ-reduced basis for a lattice is defined as follows:
Given a basis
define its Gram–Schmidt process orthogonal basis
and the Gram-Schmidt coefficients
, for any .
Also define projection functions
which project orthogonally onto the span of .
Then the basis is KZ-reduced if the following holds:
is the shortest nonzero vector in
For all ,
Note that the first condition can be reformulated recursively as stating that is a shortest vector in the lattice, and is a KZ-reduced basis for the lattice .
Also note that the second condition guarantees that the reduced basis is length-reduced (adding an integer multiple of one basis vector to another will not decrease its length); the same condition is used in the LLL reduction.
Notes
References
Theory of cryptography
Computational number theory
Lattice points |
https://en.wikipedia.org/wiki/Lutetium%20phosphide | Lutetium phosphide is an inorganic compound of lutetium and phosphorus with the chemical formula . The compound forms dark crystals, does not dissolve in water.
Synthesis
Heating powdered lutetium and red phosphorus in an inert atmosphere or vacuum:
4Lu + P4 -> 4LuP
It can also be formed in the reaction of lutetium and phosphine.
Physical properties
Lutetium phosphide forms dark cubic crystals, space group Fmm, cell parameters a = 0.5533 nm, Z = 4.
Stable in air, does not dissolve in water and reacts actively with nitric acid.
Uses
The compound is a semiconductor used in high power, high-frequency applications, and in laser diodes.
Also used in gamma radiation detectors due to its ability to absorb radiation.
References
Phosphides
Lutetium compounds
Semiconductors
Rock salt crystal structure |
https://en.wikipedia.org/wiki/EOS%20%288-bit%20operating%20system%29 | EOS is the built-in operating system of the Coleco Adam. There are bindings in high-level programming languages like BASIC.
Overview
The functions are grouped into categories as follows.
Executive calls
eos_init
eos_hard_init
eos_hard_reset_net
eos_delay_after_hard_reset
eos_synchronize_clocks
eos_scan_for_devices
eos_relocate_pcb
eos_soft_init
eos_exit_to_smartwriter
eos_switch_memory_banks
Console Output
eos_console_init
eos_console_display_regular
eos_console_display_special
Printer Interface
eos_print_character
eos_print_buffer
eos_printer_status
eos_start_print_character
eos_end_print_character
Keyboard Interface
eos_keyboard_status
eos_read_keyboard
eos_start_read_keyboard
eos_end_read_keyboard
File Operations
eos_file_manager_init
eos_check_directory_for_file
eos_find_file_1
eos_find_file_2
eos_find_file_in_fcb
eos_check_file_mode
eos_make_file
eos_update_file_in_directory
eos_open_file
eos_close_file
eos_read_file
eos_write_file
eos_trim_file
eos_initialize_directory
eos_reset_file
eos_get_date
eos_put_date
eos_delete_file
eos_rename_file
Device Operations
eos_find_pcb
eos_find_dcb
eos_request_device_status
eos_get_device_status
eos_soft_reset_device
eos_soft_reset_keyboard
eos_soft_reset_printer
eos_read_block
eos_read_one_block
eos_start_read_one_block
eos_end_read_one_block
eos_write_block
eos_write_one_block
eos_start_write_one_block
eos_end_write_one_block
eos_start_read_character_device
eos_end_read_character_device
eos_read_character_device
eos_start_write_character_device
eos_end_write_character_device
eos_write_character_device
Video RAM Management
eos_set_vdp_ports
eos_set_vram_table_address
eos_load_ascii_in_vdp
eos_put_ascii_in_vdp
eos_write_vram
eos_read_vram
eos_put_vram
eos_get_vram
eos_write_vdp_register
eos_read_vdp_register
eos_fill_vram
eos_calculate_pattern_position
eos_point_to_pattern_position
eos_write_sprite_table
Game Controllers
eos_read_ |
https://en.wikipedia.org/wiki/Rainwater%20management | Rainwater management is a series of countermeasures to reduce runoff volume and improve water quality by replicating the natural hydrology and water balance of a site, with consideration of rainwater harvesting, urban flood management and rainwater runoff pollution control.
The continuous growth of human populations and the consequent growing need for drinking water is a global problem. Rainwater is an important source of drinking water, and as a free source of water, considerable quantities can be collected from roof catchments and other surface areas for various uses. Due to water shortages, rainfall events and flooding, attention has been given to rainwater management. Rainwater management re-conceptualizes urban rainwater, transforming it from a community risk to a resource for urban development, a good rainwater management is important for the design of sanitation systems and the environment, nowadays different methods of rainwater management have been developed, including reduction of impervious surfaces, separation of rainwater and sanitary sewers, collection and reuse of rainwater, and Low-impact development (LID).
Components
Rainwater harvesting and use
Rainwater harvesting (RWH) is the process of collecting and storing rainwater rather than letting it run off. Rainwater harvesting systems are increasingly becoming an integral part of the sustainable rainwater management "toolkit" and are widely used in homes, home-scale projects, schools and hospitals for a variety of purposes including watering gardens, livestock, irrigation, home use with proper treatment and home heating. For households it is effective in reducing electricity and greenhouse gas emissions and providing domestic water; for urban agriculture, it is effective in reducing rainwater runoff and related issues; and for industry, it provides sustainability of facilities and low financial resource utilization.
Rainwater harvested from roof structures or other compact surfaces is discharged t |
https://en.wikipedia.org/wiki/Podvig%20naroda | Database "Movement of the people in the Great Patriotic War 1941-1945" () is an electronic database of documents related to the period of the Great Patriotic War. The content of the bank is formed by the documents of the Central Archives of the Russian Ministry of Defence (TsAMO), specifically award files and documents on operational control of hostilities.
As of August 30, 2020, the bank contains information about 40 391 096 awards.
The initiator of the project is the Department for Development of Information and Telecommunication Technologies of the Ministry of Defense of the Russian Federation, and telecommunications support is provided by OAO Rostelecom. The creation and technical implementation of the project is carried out by the ELAR corporation.
To digitize TsAMO documents, about 19 million sheets in total, special planetary scanners were developed. Due to the fact that the documents are 70 years old, machine recognition of the text did not cope with the task, making about 50% of errors. To solve this problem, 5,000 home operators were involved, and in order to minimize their errors, each document was recognized by two operators, and if their result matched after a machine check, the data was entered into the database.
References
External links
podvignaroda.ru
Online databases
Russian-language websites
Eastern Front (World War II) |
https://en.wikipedia.org/wiki/Telefunken%20FuBK | The Telefunken FuBK (from the German Funkbetriebskommission for "Television Service Commission") is an electronic analogue television test card developed by AEG-Telefunken and Bosch Fernseh in West Germany as the successor to the monochrome T05 test card in the late-1960s and used with analogue 625-lines PAL broadcasts.
Not as popular as the Philips PM5544, nevertheless it saw widespread use in West Germany (and later reunified Germany) and some other European, Asian, South American and African countries, and by a few commercial TV stations in Australia.
Physical equipment
The test card was generated electronically by several video-signal generators, including two variations of the Philips PM5644 generator (PM5644G/50 {PAL B/G} and PM5644G/70 {YCbCr}) and the Rohde & Schwarz SGPF-B3 (the Grundig VG 1001 test signal generator has a different pattern design, but is sometimes indicated as "FuBk" because it features similar test elements). It has also been used in conjunction with digital broadcasts by means of the PT5300 from ProTeleVision/DK Technologies.
Test card features
Some elements present on the FuBK test card are:
Cross hatch - makes up the background of the table, with 19x15 white lines over a dark gray (25% luminance) background, allowing adjustment of CRT convergence and focus;
Circle - provide a way to correct vertical and horizontal raster scan geometrical distortions;
Colour bars - EBU colour bars at 75% luminance (75/0/75/0) to adjust colour saturation and purity
Grey staircase - five bars (0%, 25%, 50%, 75%, 100%) that allow setting brightness, linearity and contrast control
2T convergence cross - check for signal reflections and group delay, help with geometrical image centering
Multiburst- four grating with sine curves at 1, 2, 3 and 4.433 MHz, as a test of horizontal resolution
Black section- check for reflections, transient response and group delay
±V/ +U ramp - two lines that allow checking PAL decoder linearity with UV signals
+V/ ±U anti |
https://en.wikipedia.org/wiki/Mur%CF%86 | Murφ (/ˈmɝ.fi/, also spelled Murphi) is an explicit-state model checker developed at Stanford University, and widely used for formal verification of cache-coherence protocols.
History
Murφ's early history is described in a paper by David Dill. The first version of Murφ was designed at Stanford University in 1990 and 1991 by Prof. David Dill and his graduate students Andreas Drexler, Alan Hu, and Han Yang, and primarily implemented by Andreas Drexler. The specification language was extensively modified and extended by David Dill, Alan Hu, C. Norris Ip, Ralph Melton, Seungjoon Park, and Han Yang. Ralph Melton implemented the new version during the summer and fall of 1992. Seungjoon Park added liveness checking and fairness constraints, but because the algorithm for liveness verification conflicted with important optimizations, particularly symmetry reduction, liveness verification was omitted in subsequent releases. C. Norris Ip implemented reversible rules and repetition constructors (which are not included in release 3.1), and added symmetry and multiset reductions (which are). Ulrich Stern implemented hash compaction, improved the use of disk, and implemented Parallel Murφ.
The last release from Stanford was release 3.1 in November of 1993. Many derivative versions of Murφ have been created since then by other groups.
Features
The Murφ compiler accepts a model written in the Murφ specification language and outputs C++ code that constitutes a verifier for that model. (That is, the C++ code, when executed, performs explicit-state model checking on the design described by the specification.) The
Murφ specification language uses guarded commands and an asynchronous, interleaving model of concurrency, with all synchronization and communication done through global variables.
The verifier checks safety properties in the form of invariants and internal assertions that are specified in the model, and checks for deadlock. It does not check liveness
properties, though M |
https://en.wikipedia.org/wiki/Neodymium%20phosphide | Neodymium phosphide is an inorganic compound of neodymium and phosphorus with the chemical formula NdP.
Preparation
Neodymium phosphide can be obtained by reacting neodymium and phosphorus in a stoichiometric ratio:
4Nd + P4 -> 4NdP
Physical properties
Neodymium phosphide forms cubic crystals, space group Fmm, cell parameters a = 0.5838 nm, Z = 4.
Uses
The compound is a semiconductor used in high power, high frequency applications, and in laser diodes.
References
Phosphides
Neodymium compounds
Semiconductors
Rock salt crystal structure |
https://en.wikipedia.org/wiki/Container%20method | The method of (hypergraph) containers is a powerful tool that can help characterize the typical structure and/or answer extremal questions about families of discrete objects with a prescribed set of local constraints. Such questions arise naturally in extremal graph theory, additive combinatorics, discrete geometry, coding theory, and Ramsey theory; they include some of the most classical problems in the associated fields.
These problems can be expressed as questions of the following form: given a hypergraph on finite vertex set with edge set (i.e. a collection of subsets of with some size constraints), what can we say about the independent sets of (i.e. those subsets of that contain no element of )? The hypergraph container lemma provides a method for tackling such questions.
History
One of the foundational problems of extremal graph theory, dating to work of Mantel in 1907 and Turán from the 1940s, asks to characterize those graphs that do not contain a copy of some fixed forbidden as a subgraph. In a different domain, one of the motivating questions in additive combinatorics is understanding how large a set of integers can be without containing a -term arithmetic progression, with upper bounds on this size given by Roth () and Szemerédi (general ).
The method of containers (in graphs) was initially pioneered by Kleitman and Winston in 1980, who bounded the number of lattices and graphs without 4-cycles. Container-style lemmas were independently developed by multiple mathematicians in different contexts, notably including Sapozhenko, who initially used this approach in 2002-2003 to enumerate independent sets in regular graphs, sum-free sets in abelian groups, and study a variety of other enumeration problems
A generalization of these ideas to a hypergraph container lemma was devised independently by Saxton and Thomason and Balogh, Morris, and Samotij in 2015, inspired by a variety of previous related work.
Main idea and informal statement
Many proble |
https://en.wikipedia.org/wiki/AMRFinderPlus | The AMRFinderPlus tool from the National Center for Biotechnology Information (NCBI) is a bioinformatic tool that allows users to identify antimicrobial resistance determinants, stress response, and virulence genes in bacterial genomes. This tool's development began in 2018 (as AMRFinder) and is still underway. The National Institutes of Health funds the development of the software and the databases it uses.
Usage
AMRFinderPlus is used by NCBI's Pathogen Detection Project, which clusters and finds similar pathogen genomic sequences from food, environmental sources, and patients. AMRFinderPlus is run for each bacterial isolate in the Pathogen Detection Project, and the findings are provided for public use. Since its scientific publication in 2021, it has also gathered citations from other users.
Database design and curation
AMRFinderPlus can detect acquired antibiotic resistance, stress response, and virulence genes, and genetic mutations that are known to confer antibiotic resistance. When AMRFinderPlus was initially developed and distributed, there were already multiple databases containing antibiotic resistance determinants. The team collaborated with database developers, expert panels, and others to consolidate these sources and create a high-quality resource that addressed limitations in these different data sources that the community had highlighted at the time. The NCBI team also collaborates with expert groups to develop the database and its annotation on a regular basis. Continuous evaluation of review papers and new reports of resistance proteins augment these sources.
While some AMR gene identification tools rely on BLAST-based methodologies, others employ hidden Markov model (HMM) approaches. BLAST-based methods can identify particular alleles and genes that are closely related, but they often apply arbitrary cutoffs that can misidentify AMR genes or assign resistance to non-AMR genes. In AMRFinderPlus, custom BLAST cutoffs are created for each gene |
https://en.wikipedia.org/wiki/Europium%28III%29%20phosphide | Europium phosphide is an inorganic compound of europium and phosphorus with the chemical formula EuP. Other phosphides are also known.
Preparation
Heating powdered europium and red phosphorus in an inert atmosphere or vacuum:
4 Eu + P4 → 4 EuP
Passing phosphine through a solution of europium in liquid ammonia:
Eu + 2PH3 → Eu(PH2)2 + H2
Eu(PH2)2 is formed, which then decomposes to europium(III) phosphide and phosphine:
2Eu(PH2)2 → 2EuP + 2PH3 + H2
Properties
Europium(III) phosphide forms dark crystals which are stable in air and do not dissolve in water. Like sodium chloride, it crystallizes cubically in the space group Fm3m with cell parameter a = 575.5 nm with four formula units per unit cell. Europium(III) phosphide tends to form europium(II) oxide (EuO) in air, and pure EuP shows Van Vleck paramagnetism. The vapor pressure of EuP is 133-266.6 Pa at 1273 K.
Europium(III) phosphide actively reacts with nitric acid.
Uses
The compound is a semiconductor used in high power, high frequency applications and in laser diodes.
References
Phosphides
Europium(III) compounds
Semiconductor materials
Rock salt crystal structure |
https://en.wikipedia.org/wiki/Niobium%20phosphide | Niobium phosphide is an inorganic compound of niobium and phosphorus with the chemical formula NbP.
Synthesis
Sintering powdered niobium and phosphorus:
4Nb + P4 -> 4NbP
Physical properties
The compound is a unique material combining topological and conventional electronic phases. Its superfast electrons demonstrate extremely large magnetoresistance, so NbP may be suitable for use in new electronic components.
Niobium phosphide forms dark gray crystals of the tetragonal system, space group , cell parameters , , .
It does not dissolve in water.
Niobium phosphide, like tantalum arsenide TaAs, is a topological Weyl semimetal.
Uses
The compound is a semiconductor used in high power, high frequency applications and in laser diodes.
References
Phosphides
Niobium(III) compounds
Semiconductors |
https://en.wikipedia.org/wiki/Transpositions%20matrix | Transpositions matrix (Tr matrix) is square matrix, , , which elements are obtained from the elements of given n-dimensional vector as follows: , where denotes operation "bitwise Exclusive or" (XOR). The rows and columns of Transpositions matrix consists permutation of elements of vector X, as there are n/2 transpositions between every two rows or columns of the matrix
Example
The figure below shows Transpositions matrix of order 8, created from arbitrary vector
Properties
matrix is symmetric matrix.
matrix is persymmetric matrix, i.e. it is symmetric with respect to the northeast-to-southwest diagonal too.
Every one row and column of matrix consists all n elements of given vector without repetition.
Every two rows matrix consists fours of elements with the same values of the diagonal elements. In example if and are two arbitrary selected elements from the same column q of matrix, then, matrix consists one fours of elements , for which are satisfied the equations and . This property, named “Tr-property” is specific to matrices.
The figure on the right shows some fours of elements in matrix.
Transpositions matrix with mutually orthogonal rows (Trs matrix)
The property of fours of matrices gives the possibility to create matrix with mutually orthogonal rows and columns ( matrix ) by changing the sign to an odd number of elements in every one of fours , . In [5] is offered algorithm for creating matrix using Hadamard product, (denoted by ) of Tr matrix and n-dimensional Hadamard matrix whose rows (except the first one) are rearranged relative to the rows of Sylvester-Hadamard matrix in order , for which the rows of the resulting Trs matrix are mutually orthogonal.
where:
"" denotes operation Hadamard product
is n-dimensional Identity matrix.
is n-dimensional Hadamard matrix, which rows are interchanged against the Sylvester-Hadamard[4] matrix in given order for which the rows of the resulting matrix are mutually orthogonal.
is |
https://en.wikipedia.org/wiki/Spectral%20submanifold | In dynamical systems, a spectral submanifold (SSM) is the unique smoothest invariant manifold serving as the nonlinear extension of a spectral subspace of a linear dynamical system under the addition of nonlinearities. SSM theory provides conditions for when invariant properties of eigenspaces of a linear dynamical system can be extended to a nonlinear system, and therefore motivates the use of SSMs in nonlinear dimensionality reduction.
Definition
Consider a nonlinear ordinary differential equation of the form
with constant matrix and the nonlinearities contained in the smooth function .
Assume that for all eigenvalues of , that is, the origin is an asymptotically stable fixed point. Now select a span of eigenvectors of . Then, the eigenspace is an invariant subspace of the linearized system
Under addition of the nonlinearity to the linear system, generally perturbs into infinitely many invariant manifolds. Among these invariant manifolds, the unique smoothest one is referred to as the spectral submanifold.
An equivalent result for unstable SSMs holds for .
Existence
The spectral submanifold tangent to at the origin is guaranteed to exist provided that certain non-resonance conditions are satisfied by the eigenvalues in the spectrum of . In particular, there can be no linear combination of equal to one of the eigenvalues of outside of the spectral subspace. If there is such an outer resonance, one can include the resonant mode into and extend the analysis to a higher-dimensional SSM pertaining to the extended spectral subspace.
Non-autonomous extension
The theory on spectral submanifolds extends to nonlinear non-autonomous systems of the form
with a quasiperiodic forcing term.
Significance
Spectral submanifolds are useful for rigorous nonlinear dimensionality reduction in dynamical systems. The reduction of a high-dimensional phase space to a lower-dimensional manifold can lead to major simplifications by allowing for an accurate description |
https://en.wikipedia.org/wiki/Cloud%20workload%20protection%20platform | A cloud workload protection platform (CWPP) is a computer security software aimed at securing (potentially virtual) computer machines. CWPPs are usually agent-based, meaning that a software agent is running permanently within the machine to be protected, collecting security-relevant data and events and sending those to a cloud-based service. The cloud-based service monitors all the machines under its supervision, derives alerts and notifies users about corresponding potential security threats.
Gartner maintains a list of CWPP vendor-based solutions.
References |
https://en.wikipedia.org/wiki/DOS%20Power%20Tools | DOS Power Tools: Techniques, Tricks and Utilities is a book by Paul Somerson, first published in 1988 by Bantam Books and sponsored by PC Magazine. The book offers a guide to approaching MS-DOS (and its cousin PC DOS) as well as various tricks and utility programs—the latter provided as x86 assembly source code listings and as compiled .COM and .EXE executables on an accompanying floppy disk (later expanded to three disks). The book was a best-seller and received positive critical reception.
The first edition of the book was written to accompany versions of DOS from 2.0 through 3.3. The book was revised in 1992 to support version 5.0.
Contents
The first edition of DOS Power Tools is divided into five parts. The first part, "Getting Up to Speed", comprises six chapters discussing the background and development of DOS; the basic principles of DOS and its interactions with hard drives; an introduction to binary and hexadecimal encoding and x86 instructions; PC keyboard scan codes; and the basics of CPUs, ROM and RAM. The second part, "The DOS Tools", describes two programs included with DOS—EDLIN.COM, the line editor, and DEBUG.COM, the assembler/debugger—as well as various .SYS files. The third part, "Power User Secrets", defines batch files and their various syntax; DOS environment variables; ANSI color codes; EGA video modes; the rest of the programs included with DOS versions 2.0 through 3.3, such as GRAPHICS.COM, XCOPY and FDISK; and concludes with a troubleshooting guide in case the PC crashes. The fourth part, "The Utilities DOS Forgot", is a compendium of source code listings for various bespoke programs and utilities, written in x86 assembly and in GW-BASIC. The fifth and final part, "Quick Reference", provides a glossary of the primary DOS commands and their flags; CONFIG.SYS directives; batch file syntax; and comprehensive glossaries for EDLIN, DEBUG, and ANSI.SYS.
Sales and reception
DOS Power Tools was a hot-seller for Bantam Books' Computer Books impri |
https://en.wikipedia.org/wiki/AhmadiPedia | AhmadiPedia (; a portmanteau of "The Ahmadiyya Encyclopaedia") is an online encyclopedia dedicated to the study of the Worldwide Ahmadiyya Muslim Community. It is edited and maintained by the Ahmadiyya Archive & Research Centre (ARC) and is an official publication of the Ahmadiyya Muslim Jamaat.
Background
According to the curator at ARC, "a need was felt that a resource is created where Ahmadis and even non-Ahmadis could search for information about the Ahmadiyya Muslim Jamaat." Hence, AhmadiPedia was launched.
Launch
AhmadiPedia was launched on 2 July 2021 by Hazrat Mirza Masroor Ahmad, the fifth worldwide head of the Ahmadiyya Muslim Jamaat, after the Friday prayers. Announcing the launch during his Friday sermon, he stated: I would like to make an announcement and that is that an Ahmadiyya Encyclopaedia has been created and will be launched today; it has been prepared by the Central Ahmadiyya Archive & Research Centre.
They began work on it some time ago and now, by the grace of Allah the Almighty, this website is being made available... It is available on www.ahmadipedia.org, where a homepage containing a search engine will open and can be used to search for information...
Content
AhmadiPedia is edited by a team of editors at the ARC which draws on the primary sources of the Ahmadiyya Muslim Community for its content. The encyclopedia entries give concise information but provide links and references to the Community's literature for further study.
Users have also been given the option to provide material via the 'contribute' page, which is then edited and uploaded to the website by the editors.
Censorship of AhmadiPedia
Pakistan Telecommunication Authority (PTA) regularly blocks content from Ahmadiyya websites, including AhmadiPedia.org. Hence, just over a month into its launch, AhmadiPedia was blocked in Pakistan.
References
External links
Friday Sermon mentioning the launch of AhmadiPedia
Khalifa Launches AhmadiPedia (MTA International news re |
https://en.wikipedia.org/wiki/Metabolic%20flexibility | Metabolic flexibility is the capacity to alter metabolism in response to exercise or available fuel (especially fats and carbohydrates). Metabolic inflexibility was first described as the ability to generate energy through either aerobic or anaerobic respiration or as the inability of muscle to increase glucose oxidation in response to insulin. An organism can also be said to have metabolic flexibility if it is capable of metabolizing either carbohydrate or fat efficiently, depending on availability of those fuels.
With aging there is a decrease in metabolic flexibility due to a decline in pyruvate dehydrogenase activity which results in pyruvate increasingly being anaerobically converted to lactate rather than aerobically converted to acetyl-CoA. Similarly, a virus-induced cytokine storm can compromise metabolic flexibility by inactivating the pyruvate dehydrogenase complex and other enzymes.
See also
Insulin resistance
References
Biochemistry
Medical terminology |
https://en.wikipedia.org/wiki/Advanced%20packaging%20%28semiconductors%29 | Advanced packaging is the aggregation and interconnection of components before traditional integrated circuit packaging. Advanced packaging allows multiple devices (electrical, mechanical, or semiconductor) to be merged and packaged as a single electronic device. Unlike traditional integrated circuit packaging, advanced packaging employs processes and techniques that are performed at semiconductor fabrication facilities. Advanced packaging thus sits between fabrication and traditional packaging -- or, in other terminology, between BEoL and post-fab. Advanced packaging includes multi-chip modules, 3D ICs, 2.5D ICs, heterogeneous integration, fan-out wafer-level packaging, system-in-package, quilt packaging, combining logic (processors) and memory in a single package, die stacking, several chiplets or dies in a package, combinations of these techniques, and others.
Advanced packaging can help achieve performance gains through the integration of several devices in one package and associated efficiency gains (by reducing the distances signals have to travel, in other words reducing signal paths), and allowing for high numbers of connections between devices, without having to resort to smaller transistors which have become increasingly more difficult to manufacture.
Advanced Packaging is considered fundamental in expanding the Moore’s Law.
References
Semiconductor technology |
https://en.wikipedia.org/wiki/ChoKyun%20Rha | ChoKyun Rha (October 5, 1933 – March 2, 2021) was a Korean-born American food technologist, inventor, and professor of biomaterials science and engineering at the Massachusetts Institute of Technology (MIT). She was the first Asian woman awarded tenure at MIT.
Early life
ChoKyun Rha was born in Seoul, the daughter of SaeJin Rha and Young Soon Choi Rha. Her father was a physician and dean of the medical school at Seoul National University. She moved to the United States in 1956, and attended Miami University in Ohio, before enrolling at MIT as an undergraduate. She finished a bachelor's degree in 1962, with a senior thesis on the storage of dried scallions. She stayed at MIT to earn master's degrees in 1964 and 1966, and completed a doctoral degree in 1967, with a dissertation titled "Thermal Sterilization of Flexibly Packaged Foods".
Career
Rha was a professor of biomaterials science and engineering at MIT, until her retirement in 2006. In 1980, she became the first Asian woman to earn tenure at MIT. She helped establish Genzyme, a biotechnology firm, and founded and directed the Malaysia-MIT Biotechnology Partnership Program. She endowed a professorship in industrial biotechnology at MIT. She was a co-founder of Women’s World Banking, a microfinancing program.
Rha's research focused on biochemistry and biotechnology for food and other applications. Her work was published in academic journalist including Journal of Food Science, Nature Biotechnology, Applied Microbiology and Biotechnology, Bioresource Technology, Biotechnology Letters, and British Journal of Nutrition. She earned her first of several patents in 1988, with a process for encapsulation. As part of her work in Malaysia, she developed several patented products derived from palm oil.
Publications
"Evaluation of cheese texture" (1978, with Cho Lee and Em Imoto)
"Microstructure of soybean protein aggregates and its relation to the physical and textural properties of the curd" (1978, with Cho Lee)
|
https://en.wikipedia.org/wiki/JData | JData is a light-weight data annotation and exchange open-standard designed to represent general-purpose and scientific data structures using human-readable (text-based) JSON and (binary) UBJSON formats. JData specification specifically aims at simplifying exchange of hierarchical and complex data between programming languages, such as MATLAB, Python, JavaScript etc. It defines a comprehensive list of JSON-compatible "name":value constructs to store a wide range of data structures, including scalars, N-dimensional arrays, sparse/complex-valued arrays, maps, tables, hashes, linked lists, trees and graphs, and support optional data grouping and metadata for each data element. The generated data files are compatible with JSON/UBJSON specifications and can be readily processed by most existing parsers. JData-defined annotation keywords also permit storage of strongly-typed binary data streams in JSON, data compression, linking and referencing.
History
The initial development of the JData annotation scheme started in 2011 as part of the development of the JSONLab Toolbox - a widely used open-source MATLAB/GNU Octave JSON reader/writer. The majority of the annotated N-D array constructs, such as _ArrayType_, _ArraySize_, and _ArrayData_, had been implemented in the early releases of JSONLab. In 2015, the first draft of the JData Specification was developed in the Iso2Mesh Wiki; since 2019, the subsequent development of the specification has been migrated to Github.
Releases
JData Version 0.5
The v0.5 version of the JData specification is the first complete draft and public request-for-comment (RFC) of the specification, made available on May 15, 2019. This preview version of the specification supports a majority of the data structures related to scientific data and research, including N-D arrays, sparse and complex-valued arrays, binary data interface, data-record-level compression, hashes, tables, trees, linked lists and graphs. It also describes the general approach |
https://en.wikipedia.org/wiki/Dietary%20biology%20of%20the%20Nile%20crocodile | Nile crocodiles are apex predators throughout their range. In the water, this species is an agile and rapid hunter relying on both movement and pressure sensors to catch any prey that presents itself inside or near the waterfront. Out of the water, however, the Nile crocodile can only rely on its limbs, as it gallops on solid ground, to chase prey. No matter where they attack prey, this and other crocodilians take practically all of their food by ambush, needing to grab their prey in a matter of seconds to succeed. They have an ectothermic metabolism, so can survive for long periods between meals—though when they do eat, they can eat up to half their body weight at a time. However, for such large animals, their stomachs are relatively small, not much larger than a basketball in an average-sized adult, so as a rule, they are anything but voracious eaters.
Young crocodiles feed more actively than their elders according to studies in Uganda and Zambia. In general, at the smallest sizes (), Nile crocodiles were most likely to have full stomachs (17.4% full per Cott); adults at in length were most likely to have empty stomachs (20.2%). In the largest size range studied by Cott, , they were the second most likely to either have full stomachs (10%) or empty stomachs (20%). Other studies have also shown a large number of adult Nile crocodiles with empty stomachs. For example, in Lake Turkana, Kenya, 48.4% of crocodiles had empty stomachs. The stomachs of brooding females are always empty, meaning that they can survive several months without food.
Invertebrates
The type and size of the prey depends mostly on the size of the crocodile. The diet of young crocodiles is made up largely of insects and other invertebrates, since this is the only prey the same animals can easily take. More than 100 species and genera of insects were identified among the food of crocodiles of this age. Of the insects taken there, beetles made up 58% of the diet, including Hydrophilus and Cybister |
https://en.wikipedia.org/wiki/JMesh | JMesh is a JSON-based portable and extensible file format for the storage and interchange of unstructured geometric data, including discretized geometries such as triangular and tetrahedral meshes, parametric geometries such as NURBS curves and surfaces, and constructive geometries such as constructive solid geometry (CGS) of shape primitives and meshes. Built upon the JData specification, a JMesh file utilizes the JSON and Universal Binary JSON (UBJSON) constructs to serialize and encode geometric data structures, therefore, it can be directly processed by most existing JSON and UBJSON parsers. The JMesh specification defines a list of JSON-compatible constructs to encode geometric data, including N-dimensional (ND) vertices, curves, surfaces, solid elements, shape primitives, their interactions (such as CGS) and spatial relations, together with their associated properties, such as numerical values, colors, normals, materials, textures and other properties related to graphics data manipulation, 3-D fabrication, computer graphics rendering and animations.
JMesh File Example
The following mesh (a tetrahedral mesh of a unit cube) contains 8 3-D vertices, 12 triangular faces and 6 tetrahedral elements
The above mesh can be stored in the JMesh/JSON format as
{
"_DataInfo_":{
"JMeshVersion":0.5,
"CreationTime":"19-Dec-2021 11:53:43",
"Comment":"Created by iso2mesh 1.9.5-Rev(http:\/\/iso2mesh.sf.net)"
},
"MeshVertex3":[
[0,0,0],
[1,0,0],
[0,1,0],
[1,1,0],
[0,0,1],
[1,0,1],
[0,1,1],
[1,1,1]
],
"MeshTri3":[
[1,2,4],
[1,2,6],
[1,3,4],
[1,3,7],
[1,5,6],
[1,5,7],
[2,8,4],
[2,8,6],
[3,8,4],
[3,8,7],
[5,8,6],
[5,8,7]
],
"MeshTet4":[
[1,2,4,8],
[1,3,4,8],
[1,2,6,8],
[1,5,6,8],
[1,3,7,8],
[1,5,7,8]
]
}
The optional "_DataInfo_" record can contain additional metadata according to JData specification.
Instead of using dimension-specific mesh data constructs, i.e. MeshVertex3, MeshTri3, and MeshTet4, one can also r |
https://en.wikipedia.org/wiki/Median%20mechanism | A median mechanism is a voting rule that allows people to decide on a value in a one-dimensional domain. Each person votes by writing down his/her ideal value, and the rule selects a single value which is (in the basic mechanism) the median of all votes.
The median mechanism can be used, for example, to decide on the size of the country's budget: each person says what the ideal budget size should be, and the chosen size is the median of the declared values. Another possible application is deciding how long the annual school vacation should be: each person says the ideal length in days, and the median is selected. A third example is: deciding what temperature the air-conditioner in an office should be set to. A fourth example is a facility location problem in one dimension.
An important feature of the median mechanism is that it is truthful: if the utility of each voter is higher whenever the chosen value is closer to his ideal value, then an optimal strategy for each voter is to declare his true ideal value, regardless of what other voters say. This is in contrast to other natural mechanisms, such as the average mechanism. With the average mechanism, if the current average is lower than a voter's ideal value, then it may be optimal for the voter to declare a higher value (and vice versa), in order to "pull" the chosen value towards his ideal value. The median mechanism is immune to such manipulations.
Moreover, every mechanism that is truthful and anonymous is a generalized median mechanism - a mechanism that inserts some fixed "society votes" and then selects the median (see below).
Assumptions
Society wants to choose a value from a one-dimensional set, which can be described as a subset of the real line, e.g. the real interval [0,1]. There are some n voters. Each voter i has an ideal value pi, also called the peak of i.
The utility of voter i depends on the chosen value: the voter is happier if the chosen value is closer to pi. Formally, the utilities satisf |
https://en.wikipedia.org/wiki/Complex%20hyperbolic%20space | In mathematics, hyperbolic complex space is a Hermitian manifold which is the equivalent of the real hyperbolic space in the context of complex manifolds. The complex hyperbolic space is a Kähler manifold, and it is characterised by being the only simply connected Kähler manifold whose holomorphic sectional curvature is constant equal to -1. Its underlying Riemannian manifold has non-constant negative curvature, pinched between -1 and -1/4 (or -4 and -1, according to the choice of a normalization of the metric): in particular, it is a CAT(-1/4) space.
Complex hyperbolic spaces are also the symmetric spaces associated with the Lie groups . They constitute one of the three families of rank one symmetric spaces of noncompact type, together with real and quaternionic hyperbolic spaces, classification to which must be added one exceptional space, the Cayley plane.
Construction of the complex hyperbolic space
Projective model
Let be a pseudo-Hermitian form of signature in the complex vector space . The projective model of the complex hyperbolic space is the projectivized space of all negative vectors for this form:
As an open set of the complex projective space, this space is endowed with the structure of a complex manifold. It is biholomorphic to the unit ball of , as one can see by noting that a negative vector must have non zero first coordinate, and has a unique representant with first coordinate equal to 1 in the projective space. The condition when is equivalent to . The map sending the point of the unit ball of to the point of the projective space thus defines the required biholomorphism.
This model is the equivalent of the Poincaré disk model. Contrary to the real hyperbolic space, the complex projective space cannot be defined as a sheet of the hyperboloid , because the projection of this hyperboloid onto the projective model has connected fiber (the fiber being in the real case).
A Hermitian metric is defined on in the following way: if belo |
https://en.wikipedia.org/wiki/Donald%20Kreider | Donald Lester Kreider (December 5, 1931 – December 7, 2006) was an American mathematician and educator who served as president of the Mathematical Association of America (1993–1994).
Early life
Kreider was born on December 5, 1931, in Lancaster, Pennsylvania. He attended high school in Lititz, Pennsylvania, and college at Lebanon Valley College, where he received a bachelor's degree in 1953. In 1959, he received a PhD in mathematics from the Massachusetts Institute of Technology for a thesis in recursive function theory supervised by Hartley Rogers.
Career
Kreider spent a postdoctoral year at MIT before joining the Department of Mathematics at Dartmouth College in 1960. At both MIT and Dartmouth, Kreider was known for excellent teaching. His advisor Hartley Rogers at MIT commented that "he had a graduate student [who] was an extraordinary teacher [and] won the Goodwin Medal for teaching at MIT". John Kemeny at Dartmouth remarked that it was difficult to find faculty who could teach well at both the undergraduate and graduate levels, but that "occasionally you are lucky—Don
Kreider is an example. Don is spectacular at anything he teaches."
Initially, Kreider continued research and writing in recursive function theory, working with Robert W. Ritchie. But he increasingly turned his attention to mathematical pedagogy, writing textbooks in recursive function theory, differential equations, and linear analysis with colleagues in the Department of Mathematics.
Starting in 1960, Kreider became active in the Committee on the Undergraduate Program in Mathematics (CUPM) at the Mathematical Association of America (MAA), where he later led the Subpanel on Calculus and received one of the first grants in the Calculus Initiative launched by the National Science Foundation in 1989.
Kreider had a long-standing interest in the use of computation in teaching calculus. Working with John Kemeny and Thomas E. Kurtz, he developed programs that provided
automatic feedback to st |
https://en.wikipedia.org/wiki/Lanthanum%20phosphide | Lanthanum phosphide is an inorganic compound of lanthanum and phosphorus with the chemical formula LaP.
Synthesis
Lanthanum phosphide can be made by heating lanthanum metal with excess phosphorus in a vacuum:
4 La + P4 → 4 LaP
Physical properties
Lanthanum phosphide forms black crystals of a cubic system, space group Fm3m, cell parameters a = 0.601 nm, with number of formulas per unit cell Z = 4.
The crystals are very unstable and decompose in the open air.
Chemical properties
Lanthanum phosphide reacts with water, releasing highly toxic phosphine gas:
LaP + 3H2O → La(OH)3 + PH3
Uses
Lanthanum phosphide compound is a semiconductor used in high power, high frequency applications, and in laser diodes.
Lanthanum polyphosphide
In addition to the simple phosphide, LaP, lanthanum and phosphorus can also form phosphorus-rich compounds such as LaP5 and LaP7.
References
Phosphides
Lanthanum compounds
Semiconductors
Rock salt crystal structure |
https://en.wikipedia.org/wiki/Workshop%20on%20Geometric%20Methods%20in%20Physics | The Workshop on Geometric Methods in Physics (WGMP) is a conference on mathematical physics focusing on geometric methods in physics . It is organized each year since 1982 in the village of Białowieża, Poland. It is organized by the Chair of Mathematical Physics of Faculty of Mathematics, University of Białystok. Its founder and main organizer is Anatol Odzijewicz.
WGMP takes place in its home venue, in the heart of the Białowieża National Park. A number of social events, including campfire, an excursion to the Białowieża forest and a banquet, are usually organized during the week.
Notable participants
In the past, Workshops were attended by scientists including: Roy Glauber, Francesco Calogero, Ludvig Faddeev, Martin Kruskal, :es:Bogdan Mielnik, Emma Previato, Stanisław Lech Woronowicz, Vladimir E. Zakharov, Dmitry Anosov, :de:Gérard Emch, George Mackey, :fr:Moshé Flato, Daniel Sternheimer, Tudor Ratiu, Simon Gindikin, Boris Fedosov, :pl:Iwo Białynicki-Birula, Jędrzej Śniatycki, Askolʹd Perelomov, Alexander Belavin, Yvette Kosmann-Schwarzbach, :pl:Krzysztof Maurin, Mikhail Shubin, Kirill Mackenzie.
Special sessions
Many times special sessions were scheduled within the programme of the Workshop. In the year 2016 there was a session "Integrability and Geometry" financed by National Science Foundation. In the year 2017 there was a session dedicated to the memory and scientific achievements of S. Twareque Ali, long time participant and co-organizer of the Workshop. In the year 2018 there was a session dedicated to scientific achievements of prof. Daniel Sternheimer on the occasion of his 80th birthday. In the previous years, there were sessions dedicated to other prominent mathematicians and physicists such as S.L. Woronowicz, G. Emch, B. Mielnik, F. Berezin.
School on Geometry and Physics
Since 2012 the Workshop is accompanied by a School on Geometry and Physics, which is targeted at young researchers and graduate students. During the School several courses by le |
https://en.wikipedia.org/wiki/Dana%20S.%20Richards | Dana S. Richards is a writer, mathematics popularizer and Associate Professor in Computer Science at George Mason University.
His research interests include comparisons of protein sequences, Steiner tree algorithms, information dissemination in networks, parallel heuristics, methodology for computationally intractable problems and parallel algorithms for median filters. He is the longtime bibliographer of polymath Martin Gardner.
Education and career
Richards received an M.S. from the University of Virginia in 1976 and a Ph.D. in computer science from the University of Illinois at Urbana-Champaign under Chung Laung Liu in 1984.
He was an Assistant Professor of Computer Science at the University of Virginia, and a Program Director of Theory of Computing at the National Science Foundation (June 1993 through May 1994).
He has written or edited seven books and numerous journal articles. In addition, he is a reviewer for many journals, and has received numerous research awards. He became an Associate Professor of Computer Science at George Mason University in 1994.
Martin Gardner
Dana Richards was a friend of Martin Gardner going back to the 1970s, and in his writing and speaking he often memorialized and popularized Gardner's work.
In 2006 he edited The Colossal Book of Short Puzzles and Problems which collected all of Gardner's short puzzles in one volume. He wrote Gardner's obituary in Science and in 2023 he published a comprehensive bibliography of Gardner's works.
Since Gardner's death in 2010 events called Celebration of Mind are held every October which include games, magic and puzzles in the Gardner tradition, and Richards is frequently featured at these events discussing Gardner's life and work.
Books
The Bibliography of Martin Gardner, June, 2023
Dear Martin / Dear Marcello: Gardner and Truzzi on Skepticism by Dana Richards, April 28, 2017
Problems in sorting and graph algorithms OCLC 12048476
The colossal book of short puzzles and problems
Th |
https://en.wikipedia.org/wiki/Thulium%20phosphide | Thulium phosphide is an inorganic compound of thulium and phosphorus with the chemical formula TmP.
Synthesis
Reaction of thulium metal with phosphorus:
4 Tm + P4 → 4 TmP
Physical properties
The dense phosphide film will prevent further reactions inside the metal. After etching gallium arsenide, an epitaxial layer of thulium phosphide can be grown on the surface to obtain a TmP/GaAs heterostructure.
The compound forms crystals of a cubic system, space group Fm3m. TmP crystallizes in a NaCl-type structure at ambient pressure.
Uses
The compound is a semiconductor used in high power, high frequency applications and in laser and other photo diodes.
References
Phosphides
Thulium compounds
Semiconductors
Rock salt crystal structure |
https://en.wikipedia.org/wiki/Pan%20trap | A pan trap is a type of insect trap used to sample the abundance and diversity of insects, primarily used to capture small Hymenoptera. Pan traps are typically constructed with a bowl with shallow sides filled with water and soap or a preservative and killing agent. Yellow is the most commonly used color, but other colors including blue, white, and red are used to target different insect species.
Trap construction
A pan trap consists of a shallow bowl, typically made of colored plastic, filled with soapy water, salt, propylene glycol, antifreeze, or combinations of other preservatives and killing agents. Salt and propylene glycol are sometimes included as preservatives or to reduce evaporative water loss. Insects fly into the soapy water and are unable to escape and are preserved in the water for research usage. Some traps have been mounted on trees to sample the communities of parasitoid wasps of the invasive beetle, Emerald ash borer.
Colors
The color of pan traps attracts diverse groups of flying insects. Some pollinators confuse the traps with natural flowers, causing the capture of flying pollinator species, including bees. Some studies have suggested that bee species are more attracted and likely to be captured in blue or white pans compared to yellow pans. However, yellow and white pan traps consistently collect the largest number of species.
References
Pest trapping
Entomology equipment |
https://en.wikipedia.org/wiki/Triller%20%28company%29 | Triller, Inc is an American company specializing in online video, social media, and combat sports. It is named after, and is the owner of, the eponymous social networking service Triller; which was launched in 2015 by co-founders David Leiberman and Sammy Rubin.
History
On March 9, 2021, Triller acquired Verzuz.
On April 14, 2021, Triller acquired video streaming service FITE TV, and customer engagement service Amplify.at.
On November 22, 2021, Triller acquired influencer event firm Thuzio.
On December 22, 2021, Triller announced its intention to merge with SeaChange International and go public. Under the terms of the deal, Triller shareholders would own at least 97.7% of the combined company. The transaction is expected to close in the second quarter of 2022. It was later announced that the combined entity would be renamed TrillerVerz Company upon the merger's closure. On June 14, 2022, it was reported that Triller would back out of the merger with SeaChange in order to pursue an IPO without a merger
On February 24, 2022, Triller acquired a majority stake in the Bare Knuckle Fighting Championship.
Assets
Streaming services
FITE TV
TrillerTV
Social media
Triller
Cliqz
Combat sports
Bare Knuckle Fighting Championship
Triller Fight Club
Pillow Fight Championship
Other brands and properties
List of other brands and properties owned by Triller, Inc
Thuzio
Verzuz
Amplify.AI
Fangage
Crosshype
Julius
Flipps Media
Metaverz
References
2015 introductions
Bare Knuckle Fighting Championship
Boxing organizations
Internet properties established in 2015
Music industry
Online content distribution
Social networking services
Social media companies of the United States
Streaming media systems
Subscription video streaming services |
https://en.wikipedia.org/wiki/COP400 | The COP400 or COP II is a 4-bit microcontroller family introduced in 1977 by National Semiconductor as a follow-on product to their original PMOS COP microcontroller. COP400 family members are complete microcomputers containing internal timing, logic, ROM, RAM, and I/O necessary to implement dedicated controllers. Some COP400 devices were second-sourced by Western Digital as the WD4200 family. In the Soviet Union several COP400 microcontrollers were manufactured as the 1820 series (e.g. the COP402 with designation КР1820ВЕ1).
The COP400 is implemented in CMOS or N-channel silicon gate MOS technology. It was typically packaged in 24- or 28-pin DIP packages. Instruction cycle time of the faster family members is 4 microseconds. The COP400 family offered several memory and pinout configurations.
Notable products that used COP400-family chips include the Apple Lisa, Milton Bradley and Mattel electronic games, Coleco Head to Head Basketball, the Grundy Newbrain, and others.
Memory
The COP400 uses separate memory spaces for ROM and RAM. ROM addresses are 11-bit maximum, while data addresses are 7-bit maximum.
ROM
Program memory consists of a 512, 1024, or 2048 × 8-bit ROM. ROM bytes may be program instructions, program data, or jump address pointers. Due to the special characteristics associated with the JP and JSRP instructions, ROM must often be conceived of as organized into pages of 64 bytes each. Also, because of the unique operations performed by the LQID and JID instructions, ROM pages must sometimes be thought of as organized into blocks of 256 bytes.
RAM
Data memory consists of a 32, 64, or 128 × 4-bit RAM, organized as several data registers of 16 4-bit digits. RAM addressing is implemented by the 6- or 7-bit B register used as a pointer. The B register's upper 2 or 3 bits (Br) select one of 4 or 8 data registers and lower 4 bits (Bd) select one of 16 4-bit digits in the selected data register. The 4-bit contents of the RAM digit pointed to by the B registe |
https://en.wikipedia.org/wiki/Zone%20theorem | In geometry, the zone theorem is a result that establishes the complexity of the zone of a line in an arrangement of lines.
Definition
A line arrangement, denoted as , is a subdivision of the plane, induced by a set of lines , into cells (-dimensional faces), edges (-dimensional faces) and vertices (-dimensional faces). Given a set of lines , the line arrangement , and a line (not belonging to ), the zone of is the set of faces intersected by . The complexity of a zone is the total number of edges in its boundary, expressed as a function of .
The zone theorem states that said complexity is .
History
This result was published for the first time in 1985; Chazelle et al. gave the upper bound of for the complexity of the zone of a line in an arrangement. In 1991, this bound was improved to , and it was also shown that this is the best possible upper bound up to a small additive factor. Then, in 2011, Rom Pinchasi proved that the complexity of the zone of a line in an arrangement is at most , and this is a tight bound.
Some paradigms used in the different proofs of the theorem are induction, sweep technique, tree construction, and Davenport-Schinzel sequences.
Generalizations
Although the most popular version is for arrangements of lines in the plane, there exist some generalizations of the zone theorem. For instance, in dimension , considering arrangements of hyperplanes, the complexity of the zone of a hyperplane is the number of facets ( - dimensional faces) bounding the set of cells (-dimensional faces) intersected by . Analogously, the -dimensional zone theorem states that the complexity of the zone of a hyperplane is . There are considerably fewer proofs for the theorem for dimension . For the -dimensional case, there are proofs based on sweep techniques and for higher dimensions is used Euler’s relation:
Another generalization is considering arrangements of pseudolines (and pseudohyperplanes in dimension ) instead of lines (and hyperplanes). Some pr |
https://en.wikipedia.org/wiki/TheFWA | FWA (Favourite Website Awards) is an international award platform that honors and rewards web designers, developers and agencies around the world for excellence within the field of web design and development. The FWA was founded in May 2000 by Rob Ford.
In November 2012, The FWA was the most visited website award program in the history of the internet, with over 170 millions site visits.
Jury
The FWA jury is composed of more than 500 web professionals (200 women + 200 men) from 35 countries.
Awards granted
FWA of the Day (FOTD) : Every day, the FWA jury selects the best project,
FWA of the Month (FOTM): Every day, the FWA jury selects the best project,
People's Choice Award (PCA) : Every year, a public vote selects the people's favourite project,
FWA of the Year (FOTY) : Every year, the FWA jury selects the best project.
Hall Of Fame
The FWA Hall of Fame was established in May 2007 (to celebrate the seventh anniversary of the FWA), as a recognition of web's greatest individuals and companies.
See also
Awwwards
References
External links
Official site
Web awards
Web development
Awards established in 2000 |
https://en.wikipedia.org/wiki/Bismuth%20phosphide | Bismuth phosphide is an inorganic compound of bismuth and phosphorus with the chemical formula BiP.
Synthesis
The reaction of sodium phosphide and bismuth trichloride in toluene (0 °C):
Na3P + BiCl3 -> BiP + 3NaCl
Physical properties
When heated in air, bismuth phosphide burns.
When heated in an atmosphere of carbon dioxide, a gradual volatilization of phosphorus is observed.
Chemical properties
This compound is oxidized when boiled in water.
All strong acids dissolve it.
Uses
The compound is a semiconductor used in high power, high frequency applications and in laser diodes.
References
Phosphides
Bismuth compounds
Semiconductors |
https://en.wikipedia.org/wiki/Holmium%20phosphide | Holmium phosphide is a binary inorganic compound of holmium and phosphorus with the chemical formula HoP. The compound forms dark crystals and does not dissolve in water.
Synthesis
Heating powdered holmium and red phosphorus in an inert atmosphere or vacuum:
4Ho + P4 -> 4HoP
Properties
Holmium phosphide forms dark crystals of a cubic system, stable in air, does not dissolve in water.
HoP belongs to the large class of NaCl-structured rare earth monopnictides.
Ferromagnetic at low temperatures.
HoP actively reacts with nitric acid.
Uses
The compound is a semiconductor used in high power, high frequency applications and in laser diodes.
References
Phosphides
Holmium compounds
Semiconductors
Rock salt crystal structure |
https://en.wikipedia.org/wiki/Egill%20Sk%C3%BAli%20Ingibergsson | Egill Skúli Ingibergsson (23 March 1926 – 22 December 2021) was an Icelandic electrical engineer and the Mayor of Reykjavík from 1978 to 1982.
Death
Egill died on 22 December 2021, at the age of 95, at Landspítalinn's palliative care unit in Kópavogur.
References
1926 births
2021 deaths
Egill Skuli Ingibergsson
Egill Skuli Ingibergsson
Egill Skuli Ingibergsson
Egill Skuli Ingibergsson |
https://en.wikipedia.org/wiki/Cristina%20Sernadas | Maria Cristina De Sales Viana Serôdio Sernadas (born 1951) is a Portuguese mathematical logician whose research topics have included object-oriented specification languages and logics for information systems, and the use of category theory in the combination ("fibring") of multiple types of logic. She is Professor for Logic and Computation in the Department of Mathematics of the Technical University of Lisbon.
Education and career
Sernadas studied mathematics at the University of Lisbon, graduating in 1973, and earned a Ph.D. in mathematics in 1980 from the University of London. Her doctoral dissertation, Multivariate Branching Processes, concerned branching processes in probability theory, and was supervised by statistician D. J. Bartholomew.
In 1988 she completed a habilitation (agregação) at the Technical University of Lisbon, and became a full professor there in 1993.
Books
Sernadas's books include:
Introdução à Teoria da Computação (Introduction to the Theory of Computing, Editorial Presença, 1993)
Introdução à Programação em Mathematica (Introduction to Programming in Mathematica, with J. Carmo, A. Sernadas, F. M. Dionísio, and C. Caleiro, IST Press, 1999; 2nd ed., 2004; 3rd ed., 2014)
Foundations of Logic and Theory of Computation (with A. Sernadas, College Publications, 2008; 2nd ed., 2012)
Analysis and Synthesis of Logics: How To Cut And Paste Reasoning Systems (with W. A. Carnielli, M. E. Coniglio, D. Gabbay, and P. Gouveia, Springer, 2008)
A Mathematical Primer on Computability (with A. Sernadas, J. Rasga and J. Ramos, College Publications, 2018)
A Mathematical Primer on Linear Optimization (with D. Gomes, A. Sernadas, J. Rasga and P. Mateus, College Publications, 2019)
Decidability of Logical Theories and Their Combination (with J. Rasga, Springer, 2020)
References
External links
1951 births
Living people
20th-century Portuguese mathematicians
Mathematical logicians
Women logicians
Women mathematicians
University of Lisbon alumni
Alumni of the Univ |
https://en.wikipedia.org/wiki/McCay%20cubic | In Euclidean geometry, the McCay cubic (also called M'Cay cubic or Griffiths cubic) is a cubic plane curve in the plane of a reference triangle and associated with it. It is the third cubic curve in Bernard Gilbert's Catalogue of Triangle Cubics and it is assigned the identification number K003.
Definition
The McCay cubic can be defined by locus properties in several ways. For example, the McCay cubic is the locus of a point such that the pedal circle of is tangent to the nine-point circle of the reference triangle . The McCay cubic can also be defined as the locus of point such that the circumcevian triangle of and are orthologic.
Equation of the McCay cubic
The equation of the McCay cubic in barycentric coordinates is
The equation in trilinear coordinates is
McCay cubic as a stelloid
A stelloid is a cubic that has three real concurring asymptotes making 60° angles with one another. McCay cubic is a stelloid in which the three asymptotes concur at the centroid of triangle ABC. A circum-stelloid having the same asymptotic directions as those of McCay cubic and concurring at a certain (finite) is called McCay stelloid. The point where the asymptoptes concur is called the "radial center" of the stelloid. Given a finite point X there is one and only one McCay stelloid with X as the radial center.
References
Triangle geometry |
https://en.wikipedia.org/wiki/Kruskal%20count | The Kruskal count (also known as Kruskal's principle, Dynkin–Kruskal count, Dynkin's counting trick, Dynkin's card trick, coupling card trick or shift coupling) is a probabilistic concept originally demonstrated by the Russian mathematician Evgenii Borisovich Dynkin in the 1950s or 1960s discussing coupling effects and rediscovered as a card trick by the American mathematician Martin David Kruskal in the early 1970s as a side-product while working on another problem. It was published by Kruskal's friend Martin Gardner and magician Karl Fulves in 1975. This is related to a similar trick published by magician Alexander F. Kraus in 1957 as Sum total and later called Kraus principle.
Besides uses as a card trick, the underlying phenomenon has applications in cryptography, code breaking, software tamper protection, code self-synchronization, control-flow resynchronization, design of variable-length codes and variable-length instruction sets, web navigation, object alignment, and others.
Card trick
The trick is performed with cards, but is more a magical-looking effect than a conventional magic trick. The magician has no access to the cards, which are manipulated by members of the audience. Thus sleight of hand is not possible. Rather the effect is based on the mathematical fact that the output of a Markov chain, under certain conditions, is typically independent of the input. A simplified version using the hands of a clock is as follows. A volunteer picks a number from one to twelve and does not reveal it to the magician. The volunteer is instructed to start from 12 on the clock and move clockwise by a number of spaces equal to the number of letters that the chosen number has when spelled out. This is then repeated, moving by the number of letters in the new number. The output after three or more moves does not depend on the initially chosen number and therefore the magician can predict it.
See also
Coupling (probability)
Discrete logarithm
Equifinality
Ergodic t |
https://en.wikipedia.org/wiki/Pipe-in-pipe%20system | A pipe-in-pipe system is a form of plumbing where all water pipes are running inside another pipe. Its purpose is to ensure that any leaks in the innermost pipe will not leak into the building structure and can be detected, as well as make for easier change of any internal pipes with leakage without opening the walls.
Parts
A pipe-in-pipe system consists of four main components: an inner pipe, an outer pipe, wall boxes, and a distribution cabinet.
Legal requirements
In Norway, domestic plumbing based on pipe-in-pipe systems (known as: rør-i-rør system) was introduced in 1995, and has since become a legal requirement in all new houses being built. Due to experience with water damages with many traditional copper pipes in Norway between 1970 and 1995, new requirements came in 1997 stating that water pipes should be easily accessible for replacement after installation. These requirements have since lead to the current de facto requirement for pipe-in-pipe plumbing.
Operation
During normal operation, the water flows through the inner water pipe, which is enclosed by the outer goods pipe. The plumbing leads back to a centrally located distribution cabinet where the pipes to all tapping points of the home are gathered in one place. In the event of any damage and leakage to the internal pipes, the external pipes must ensure that the water leak is safely diverted to the distribution cabinet where it is made visible for inspection before it is lead to a room with drains in the floor. It can be advantageous to install a water leak sensor and connect it to an automatic water stop valve which closes the water supply. In the event of visible leaks, there must also be an easily accessible manual main shut-off valve which must stop water supply to all pipes.
Installation and repairs
Due to the way pipe-in-pipe systems are installed using flexible internal and external pipes, it is possible to pull out and replace the water pipes without having to open up walls. To ensure t |
https://en.wikipedia.org/wiki/Digital%20rights%20in%20the%20Caribbean | Digital rights—human rights in relation to digital technologies—present particular challenges in the Caribbean countries, due to its geographies, political context, social inequalities and cultural diversity. While they face the same problem of digital divides as other regions, for islands the impacts of not accessing or understanding digital technologies can have particularly harmful consequences. Similar concerns could be found in terms of gender-based violence online, a global problem encompassing psychological, physical, emotional and sexual violence. This affects more acutely girls and young women and brings about special concerns within the Caribbean. However, there are other topics which are utmost problematic because of the history and type of applicable law system in countries from this region, such as in the case of digital identity and internet shutdowns. Despite variations across Caribbean countries, issues happening in one country can be replicated within the region or can affect people living in other countries.
Digital ID
Jamaica
There have been two attempts to implement the National Identification System (NIDS) bill in Jamaica. The first one was proposed in 2017 and dropped in 2019, when the Court indicated that the bill was being unjustifiably breaching Jamaicans' rights to privacy and equality, among others. In 2020, a new version of the bill was proposed. In 2021, civil society served recommendations to parliamentarians but most of them were not taken into account.
One of the many criticisms is the disproportionately large amounts of personal information being collected. Gathering biometric data was particularly signaled to be not necessary to provide legal identity and being a target for potential leaks and illegitimate access. The Jamaican government has already mistakenly exposed personal data, as seen in the JamCOVID app scandal that made public the immigration record of hundreds of thousands of travelers, as well as their COVID test re |
https://en.wikipedia.org/wiki/H%C3%BCtte | The (originally , stylized as "HÜTTE" and pronounced ) is a reference work for engineers of various disciplines. It was compiled for the first time in 1857 by the (short , translating as "the hut") of the in Berlin, from which the association of German engineers Verein Deutscher Ingenieure (VDI) emerged. The authors were members of the association. The technical illustrations were created in woodcut technique by . It is published in constantly revised editions to this day and is therefore the oldest German reference work still available today.
First edition 1857 and bibliophile reprint 2007
The book was initially divided into three sections: (Mathematics and Mechanics), (Mechanical Engineering and Technology) and (Building Science) and was originally published by the publishing house , the later , who published it until 1971.
For the 150th anniversary in 2007, the first edition was reissued as a bibliophile reprint.
Historical development
Starting with the first edition in 1857, further book series have been developed over the decades. The reference work quickly developed into a standard work for engineers and was frequently reprinted and translated into other languages due to the great demand. The first translation ever was into Russian in 1863. In 1890, the work was divided into two, in 1908 into three, and finally in 1922 into four volumes. With the 27th edition in 1949, volume four was no longer available.
An English version was published by McGraw-Hill Book Co., New York, in 1916 as "Mechanical engineers' handbook, based on the Hütte and prepared by a staff of specialists" edited by Lionel Simeon Marks. This led to Marks' Standard Handbook for Mechanical Engineers, a work, which spawn several translations on its own and is continued up to the present with its 100th anniversary 12th edition published in 2017.
Another work initially influenced by the 1936 Russian translation of the 1931 edition of Hütte is the so called Bronshtein and Semendyayev ( |
https://en.wikipedia.org/wiki/Therapeutic%20interfering%20particle | A therapeutic interfering particle is an antiviral preparation that reduces the replication rate and pathogenesis of a particular viral infectious disease. A therapeutic interfering particle is typically a biological agent (i.e., nucleic acid) engineered from portions of the viral genome being targeted. Similar to Defective Interfering Particles (DIPs), the agent competes with the pathogen within an infected cell for critical viral replication resources, reducing the viral replication rate and resulting in reduced pathogenesis. But, in contrast to DIPs, TIPs are engineered to have an in vivo basic reproductive ratio (R0) that is greater than 1 (R0>1). The term "TIP" was first introduced in 2011 based on models of its mechanism-of-action from 2003. Given their unique R0>1 mechanism of action, TIPs exhibit high barriers to the evolution of antiviral resistance and are predicted to be resistance proof. Intervention with therapeutic interfering particles can be prophylactic (to prevent or ameliorate the effects of a future infection), or a single-administration therapeutic (to fight a disease that has already occurred, such as HIV or COVID-19). Synthetic DIPs that rely on stimulating innate antiviral immune responses (i.e., interferon) were proposed for influenza in 2008 and shown to protect mice to differing extents but are technically distinct from TIPs due to their alternate molecular mechanism of action which has not been predicted to have a similarly high barrier to resistance. Subsequent work tested the pre-clinical efficacy of TIPs against HIV, a synthetic DIP for SARS-CoV-2 (in vitro), and a TIP for SARS-CoV-2 (in vivo).
Mechanism of action
Therapeutic Interfering Particles, often referred to as TIPs, are typically synthetic, engineered versions of naturally occurring defective interfering particles (DIPs), in which critical portions of the virus genome are deleted rendering the TIP unable to replicate on its own. Often a TIP has the vast majority of the vir |
https://en.wikipedia.org/wiki/Marquois%20scales | Marquois scales (also known as Marquois parallel scales or Marquois scale and triangle or military scales) are a mathematical instrument that found widespread use in Britain, particularly in military surveying, from the late 18th century to World War II.
Description
Invented around 1778 by Thomas Marquois, the Marquois scales consist of a right-angle triangle (with sides at a 3:1 ratio) and two rulers (each with multiple scales). The system could be used to aid precision when marking distances off scales, and to rapidly draw parallel lines a precise distance apart. Quick construction of precise parallel lines was useful in cartography and engineering (especially before the availability of graph paper) and Marquois scales were convenient in some challenging environments where larger equipment like a drawing board and T-square was impractical, such as field survey work and classrooms. Marquois scales fell out of favour among draftsmen in the early 20th century, although familiarity with their use was an entry requirement for the Royal Military Academy at Woolwich around the same time.
Material
Marquois scales were normally made of boxwood, though sets were sometimes made in ivory or metal.
Use
The triangle would be used for many regular set square operations, the rulers likewise would function as rulers, but the unique function was the 3:1 reduction ratio between measured distance and drawn line.
A line is drawn along the beveled edge (the side of middle-length) of the triangle. By placing a ruler against the hypotenuse of the triangle and sliding the triangle along the ruler for 3 units of the ruler's scale, drawing another line along the beveled edge results in a parallel line with a distance of only 1 unit from the original line. Using larger distances on a ruler to draw lines smaller distances apart means that margin of error reading off the scale is reduced. Additionally, the end-state is the instruments already in place to slide the triangle again to quickly |
https://en.wikipedia.org/wiki/Schoology | Schoology is a learning management system for schools and businesses, targeted mainly at schools.
History
Schoology was designed by Jonathan Friedman, Ryan Hwang, and Tim Trinidad in 2007 while studying at Washington University in St. Louis. Originally designed for sharing notes, features were gradually added and modified.
Schoology secured its first round of equity financing, totaling $1,250,000, with an investment of unknown origin in 2009 and an investment by Meakam Becker Venture Capital in June 2010. In 2012, Schoology raised $6 million in a round led by Firstmark Capital; in 2014, it raised $15 million in a funding round led by Intel Capital; in November 2015, it raised $32 million in a funding round, led by JMI Equity.
In November 2013, Schoology had over 7.5 million users across about 60,000 schools.
Use
Among Schoology's features are attendance records, grades, exams, and homework. The interface consists of a list of task and links to folders and assignments for students. Schoology can be integrated with the school's current grading system. Visually, Schoology is very similar to the environment of many social networks.
Schoology offers accounts for parents as well, mainly for viewing the grades of their children.
References
Social networking services
Learning management systems
Educational software |
https://en.wikipedia.org/wiki/Geometric%20logic | In mathematical logic, geometric logic is an infinitary generalisation of coherent logic, a restriction of first-order logic due to Skolem that is proof-theoretically tractable. Geometric logic is capable of expressing many mathematical theories and has close connections to topos theory.
Definitions
A theory of first-order logic is geometric if it is can be axiomatised using only axioms of the form
where I and J are disjoint collections of formulae indices that each may be infinite and the formulae φ are either atoms or negations of atoms. If all the axioms are finite (i.e., for each axiom, both I and J are finite), the theory is coherent.
Theorem
Every first-order theory has a coherent conservative extension.
Significance
list eight consequences of the above theorem that explain its significance (omitting footnotes and most references):
In the context of a sequent calculus such as G3c, special coherent implications as axioms can be converted directly to inference rules without affecting the admissibility of the structural rules (Weakening, Contraction and Cut);
In similar terms, coherent theories are “the theories expressible by natural deduction rules in a certain simple form in which only atomic formulas play a critical part”;
Coherent implications form sequents that give a Glivenko class. In this case, the result, known as the first-order Barr’s Theorem, states that if each Ii: 0≤i≤n is a coherent implication and the sequent I1, . . . , In ⇒ I0 is classically provable then it is intuitionistically provable;
There are many examples of coherent/geometric theories: all algebraic theories, such as group theory and ring theory, all essentially algebraic theories, such as category theory, the theory of fields, the theory of local rings, lattice theory, projective geometry, the theory of separably closed local rings (aka “strictly Henselian local rings”) and the infinitary theory of torsion abelian groups;
Coherent/geometric theories are preserved by pullback alo |
https://en.wikipedia.org/wiki/Transcriptome-wide%20association%20study | Transcriptome-wide association study (TWAS) is a genetic methodology that can be used to compare the genetic components of gene expression and the genetic components of a trait to determine if an association is present between the two components. TWAS are useful for the identification and prioritization of candidate causal genes in candidate gene analysis following genome-wide association studies. TWAS looks at the RNA products of a specific tissue and gives researchers the abilities to look at the genes being expressed as well as gene expression levels, which varies by tissue type. TWAS are valuable and flexible bioinformatics tools that looks at the associations between the expressions of genes and complex traits and diseases. By looking at the association between gene expression and the trait expressed, genetic regulatory mechanisms can be investigated for the role that they play in the development of specific traits and diseases.
Transcriptome Analysis
A transcriptome is the sum of all RNA transcripts that are present in a given cell, tissue, or organ within an organism. Transcriptomes include both mRNA, which functions as an intermediate to the central dogma; as well as noncoding RNAs that may play other roles in protein synthesis. In the central dogma, it describes how DNA is able to make proteins through transcription and translation. RNAs are present in a cell in varied concentrations, and play various roles outside of the central dogma and are able to be identified based on length and function. It is through functional elements that the transcriptional and translational activities of genes is able to be regulated. Transcriptome analysis is beneficial for obtaining information about all RNAs present and can provide valuable insight into the genetic mechanisms that are tissue specific. The transcriptome was first investigated in the 1990s in an experiment performed to identify a partial transcriptome of the human brain. Researchers were able to identify 609 |
https://en.wikipedia.org/wiki/USBM%20wettability%20index | The U.S. Bureau of Mines (USBM), developed by Donaldson et al. in 1969, is a method to measure wettability of petroleum reservoir rocks. In this method, the areas under the forced displacement Capillary pressure curves of oil and water drive processes are denoted as and to calculate the USBM index.
USBM index is positive for water-wet rocks, and negative for oil-wet systems.
Bounded USBM (or USBM*)
The USBM index is theoretically unbounded and can vary from negative infinity to positive infinity. Since other wettability indices such as Amott-Harvey, Lak wettability index and modified Lak are bounded in the range of -1 to 1, Abouzar Mirzaei-Paiaman highlighted the bounded form of USBM (called USBM*) as a replacement of the traditional USBM as
USBM* varies from -1 to 1 for strongly oil-wet and strongly water-wet rocks, respectively.
See also
Wetting
Amott test
Lak wettability index
References
Petroleum geology
Surface science
Fluid mechanics |
https://en.wikipedia.org/wiki/%C5%A0indel%20sequence | In additive combinatorics, a Šindel sequence is a periodic sequence of integers with the property that its partial sums include all of the triangular numbers. For instance, the sequence that begins 1, 2, 3, 4, 3, 2 is a Šindel sequence, with the triangular partial sums
etc. Another way of describing such a sequence is that it can be partitioned into contiguous subsequences whose sums are the consecutive integers:
This particular example is used in the gearing of the Prague astronomical clock, as part of a mechanism for chiming the clock's bells the correct number of times at each hour. The Šindel sequences are named after Jan Šindel, a Czech scientist in the 14th and 15th centuries whose calculations were used in the design of the Prague clock. The definition and name of these sequences were given by Michal Křížek, Alena Šolcová, and Lawrence Somer, in their work analyzing the mathematics of the Prague clock.
If denotes the sum of the numbers within a single period of a periodic sequence, and is odd, then only the triangular numbers up to need to be checked, to determine whether it is a Šindel sequence. If all of these triangular numbers are partial sums of the sequence, then all larger triangular numbers will be as well. For even values of , a larger set of triangular numbers needs to be checked, up to .
In the Prague clock, an auxiliary gear with slots spaced at intervals of 1, 2, 3, 4, 3, and 2 units (repeating in the example Šindel sequence in each of its rotations) is synchronized with and regulates the motion of another larger gear whose slots are spaced at intervals of 1, 2, 3, 4, 5, ..., 24 units, revolving once a day with its spacing controlling the number of chimes on each hour. In order to keep these two gears synchronized, it is important that, for every revolution of the large gear, the small gear also revolves an integer number of times. Mathematically, this means that the sum of the period of the Šindel sequence must evenly divide , the sum o |
https://en.wikipedia.org/wiki/History%20of%20research%20into%20the%20origin%20of%20life | The history of research into the origin of life encompasses theories about how life began, from ancient times with the philosophy of Aristotle through to the Miller-Urey experiment in 1952.
Panspermia
Panspermia is the hypothesis that life exists throughout the universe, distributed by meteoroids, asteroids, comets and planetoids. It does not attempt to explain how life originated, but shifts the origin to another heavenly body. The advantage is that life is not required to have formed on each planet it occurs on, but rather in a single location, and then spread about the galaxy to other star systems via cometary or meteorite impact.
Evidence for this is scant, but it finds some support in studies of Martian meteorites found in Antarctica and of extremophile microbes' survival in outer space tests. Terrestrial bacteria, particularly Deinococcus radiodurans, highly resistant to environmental hazards, could survive for at least three years in outer space, based on studies on the International Space Station.
An extreme speculation is that the biochemistry of life could have begun as early as 17 My (million years) after the Big Bang, during a supposedly habitable epoch, and that life may exist throughout the universe. Carl Zimmer has speculated that the chemical conditions, including boron, molybdenum and oxygen needed to create RNA, may have been better on early Mars than on early Earth. If so, life-suitable molecules originating on Mars would have later migrated to Earth via meteor ejections.
Spontaneous generation
General acceptance until 19th century
Traditional religion attributed the origin of life to deities who created the natural world. Spontaneous generation, the first naturalistic theory of abiogenesis, goes back to Aristotle and ancient Greek philosophy, and continued to have support in Western scholarship until the 19th century. The theory held that "lower" animals are generated by decaying organic substances. Aristotle stated that, for example, aphid |
https://en.wikipedia.org/wiki/Voyager-EUS2 | Voyager-EUS2 is a supercomputer built by Microsoft Azure, capable of 39.531 petaflops, and is ranked 14th in the TOP500 as of November 2022. Voyager-EUS2 runs from Microsoft Azure East US 2 region and it utilizes 253,440 cores on AMD EPYC CPUs along with an NVIDIA A100 GPU with 80GB memory and a Mellanox HDR Infiniband for data transfer running on Linux distribution.
See also
TOP500
References
Supercomputers |
https://en.wikipedia.org/wiki/Austin%20250hp%20gas%20turbine | The Austin 250hp gas turbine was a free turbine turboshaft engine developed by Dr John Weaving at the Austin Motor Company. It was a development of an earlier engine that had been used in the experimental Austin Princess car TUR1. Various uses for the engine were suggested such as mobile power unit and Hospital Backup Generator but it did not find any commercial use. More powerful derivates were developed but these also found no uses
References
1950s turboshaft engines
Cars powered by gas turbines
250hp gas turbine |
https://en.wikipedia.org/wiki/YugabyteDB | YugabyteDB is a high-performance transactional distributed SQL database for cloud-native applications, developed by Yugabyte.
History
Yugabyte was founded by ex-Facebook engineers Kannan Muthukkaruppan, Karthik Ranganathan, and Mikhail Bautin. At Facebook, they were part of the team that built and operated Cassandra and HBase during a period of significant growth in workloads such as Facebook Messenger and Facebook's Operational Data Store.
The founders came together in February 2016 to build YugabyteDB, believing that the trends they experienced at Facebook – microservices, containerization, high availability, geographic distribution, APIs, and open-source – were relevant to all businesses, especially as they move from on-premise to cloud-native operations.
YugabyteDB was initially available in two editions: community and enterprise. In July 2019, Yugabyte open sourced previously commercial features and launched YugabyteDB as open-source under the Apache 2.0 license.
The rapid evolution of the product led to being named as a 2020 Gartner Cool Vendor in Data Management.
Yugabyte launched Yugabyte Cloud, now renamed YugabyteDB Managed, a fully managed database-as-a-service offering of YugabyteDB, in September 2021.
Funding
Six years after the company's inception, Yugabyte closed a $188 Million Series C funding round to become a Unicorn start-up with a valuation of $1.3Bn
Architecture
YugabyteDB is a distributed SQL database that aims to be strongly transactionally consistent across failure zones (i.e. ACID compliance]. Jepsen testing, the de facto industry standard for verifying correctness, has never fully passed, mainly due to race conditions during schema changes. In CAP Theorem terms YugabyteDB is a Consistent/Partition Tolerant (CP) database.
YugabyteDB has two layers, a storage engine known as DocDB and the Yugabyte Query Layer.
DocDB
The storage engine consists of a customized RocksDB combined with sharding and load balancing algorithms for the |
https://en.wikipedia.org/wiki/3D%20concrete%20printing | 3D concrete printing, or simply concrete printing, refers to digital fabrication processes for cementitious materials based on one of several different 3D printing technologies. 3D printed concrete eliminates the need for formwork, reducing material waste and allowing for greater geometric freedom in complex structures. With recent developments in mix design and 3D printing technology over the last decade, 3D concrete printing has grown exponentially since its emergence in the 1990s. Architectural and structural applications of 3D-printed concrete include the production of building blocks, building modules, street furniture, pedestrian bridges, and low-rise residential structures.
History
Automating building processes has been an area of research in architecture and civil engineering since the 20th century. The earliest approaches focused on automating masonry. In 1904, a patent for a brick-laying machine was granted to John Thomas in the US. By the 1960s, the technology developed significantly and functional equipment, such as the Motor-Mason, were in use on building sites.
At the same time, automating concrete construction processes was also being developed. Slip forming, a widely used technique today for building vertical concrete cores for high-rise buildings, was developed in the early 20th century for building silos and grain elevators. The concept was pioneered by James MacDonald, of MacDonald Engineering Chicago, and published by Milko S. Ketchum in an illustrated book: The Design of Walls, Bins, and Grain Elevators in 1907. Later, MacDonald published a scientific paper: Moving Forms for Reinforced Concrete Storage Bins in 1911. Finally, on 24 May 1917, MacDonald was granted a US patent for a device to move and elevate a concrete form in a vertical plane.
Innovations in the automation of concreting processes continued throughout the 20th century. 3D printing processes were first developed in the 1980s for photopolymers and thermoplastics. For some time, |
https://en.wikipedia.org/wiki/Hugo%20Krawczyk | Hugo Krawczyk is an Argentine-Israeli cryptographer best known for co-inventing the HMAC message authentication algorithm and contributing in fundamental ways to the cryptographic architecture of central Internet standards, including IPsec, IKE, and SSL/TLS. In particular, both IKEv2 and TLS 1.3 use Krawczyk’s SIGMA protocol as the cryptographic core of their key exchange procedures. He has also contributed foundational work in the areas of threshold and proactive cryptosystems and searchable symmetric encryption, among others.
Education
Krawczyk acquired a Bachelor of Arts in Mathematics from the University of Haifa. Later he received his Master of Science and Ph.D. in computer science from Technion - Israel Institute of Technology with Oded Goldreich as doctoral thesis advisor.
Career
Hugo Krawczyk is a Senior Principal Scientist at Amazon Web Services (AWS). Between 2019 and 2023 he was a Principal Researcher at the Algorand Foundation and part of its founding team. Prior to that, he was an IBM Fellow and Distinguished Research Staff Member at the IBM T.J. Watson Research Center in New York as a member of the Cryptography Research group from 1992 to 1997, and again from 2004 to 2019. He was an Associate Professor at the Department of Electrical Engineering at the Technion in Israel from 1997 until 2004.
Krawczyk has published over 100 papers with more than 30,000 citations, and is an inventor in 30 issued patents.
His research includes both theoretical and applied elements of cryptography, with a focus on internet security, privacy, and authentication. His most recent projects in the area include: TLS 1.3, the new-generation SSL/TLS; HKDF, the standard for key derivation embraced by TLS 1.3, Signal, WhatsApp, Facebook Messenger, and others; and OPAQUE, a password authentication protocol being standardized by the IRTF and recently deployed by Facebook in its implementation of end-to-end encrypted chat backups for WhatsApp.
Krawczyk is the author of many |
https://en.wikipedia.org/wiki/List%20of%20animals%20with%20humps | This is a list of animals that have a naturally occurring hump or humps as a part of their anatomy.
Humps may evolve, as a store of fat, as a heat control mechanism, as a development of muscular strength, as a form of display to other animals or be apparent as a consequence of some behaviour such as the diving of whales. Enlarged humps have also been selected for by some animal breeders for aesthetic or religious reasons.
Dromedary - also known as Arabian camel, is a large even-toed ungulate, of the genus Camelus, with one hump on its back. The hump stores up to 80 lb (36 kg) of fat, which the camel can break down into energy to meet its needs when resources are scarce; the hump also helps dissipate body heat.
Bactrian camel - also known as the Mongolian camel or domestic Bactrian camel, is a large even-toed ungulate native to the steppes of Central Asia. It has two humps on its back, in contrast to the single-humped dromedary camel. Like the dromedary it can break down fat in its humps into energy to meet its needs when resources are scarce; and use them to help dissipate body heat.
Wild Bactrian camel - Once thought to have originated from escaped domesticated Bactrian camels, genetic studies have established it as a separate species which diverged from the Bactrian camel about 1.1 million years ago. A critically endangered species living in parts of northwestern China and southwestern Mongolia.
American bison - commonly known as the American buffalo or simply buffalo. Has a noticeable hump between its shoulder blades which unlike the camel is formed from muscle. The muscles assist in the shovelling of snow in winter allowing access to food.
Moose - or elk (in Eurasia) is the largest and heaviest extant species in the deer family. Like the bison it has evolved large muscles on top of its neck to help it shovel snow to find winter feed.
White rhinoceros - This species of rhino has a bulge on the back of its neck made of thickened skin, a pad of fat, thick m |
https://en.wikipedia.org/wiki/Romanian%20Olympiad%20in%20Informatics | The Romanian Olympiad in Informatics (, ) is an annual competitive programming contest for secondary school students in Romania. It gathers about 300 high-school students (9th to 12th grade) and about 160 gymnasium students (5th to 8th grade).
The contest takes place over two days, in sessions of 3–5 hours each, and consists of providing computationally efficient solutions to one to four problems of an algorithmic nature. Contestants compete individually. To participate, students must first qualify within their school, then town/city, then county. At the end of the Olympiad, a special contest further selects the top ~20 students for the International Olympiad in Informatics (IOI). Since 1990, Romanian students have won 32 gold medals at the IOI, ranking the country #4 worldwide.
History
The first Romanian Olympiad in Informatics was held in 1978 and consisted of a hand-written portion, and a computer portion, the latter giving a choice of programming language among Fortran, COBOL and ASSIRIS.
Other editions included:
2017 - Brașov, 340 high-school students, 20–25 April
2016 - Bucharest, 21–24 April (gymnasium)
2015 - Târgovişte, 330 high-school students, 3–8 April
2014 - Slobozia, 220 gymnasium students, 10–14 April
2013 - Timisoara, 30 March – 5 April
2010 - Slatina, 126 gymnasium students, 30 January – 2 February, and Constanta, 287 high-school students in April
See also
International Olympiad in Informatics
Central European Olympiad in Informatics, founded by and often hosted in Romania
References
External links
olimpiada.info
Programming contests
European student competitions
Information technology organizations based in Europe |
https://en.wikipedia.org/wiki/Opera%20Omnia%20Leonhard%20Euler | Opera Omnia Leonhard Euler (Leonhardi Euleri Opera omnia) is the compilation of Leonhard Euler's scientific writings. The project of this compilation was undertaken by the Euler Committee of the Swiss Academy of Sciences, established in 1908, and is ongoing . The Committee decided on "the edition of the Collected Works of Leonhard Euler in the original languages, convinced of rendering the entire scientific world a service thereby", and, in 1919, it indicated to collect “All works from Leonhard Euler, hitherto unseen or already printed, coming from St-Petersburg or elsewhere need to be integrated. This also includes the scientific letters of Euler”. The project has been supported by the international community, notably the Petersburg Academy of Sciences where Euler taught and which lent out its Euler materials in 1910. Publishing Euler's Opera Omnia has been termed "one of the most extraordinary projects in publishing".
The Opera Omnia, excepting correspondences still being compiled in IVA9, was made available online in 2022 via the Opera-Bernoulli-Euler, which is working to make "the entire work of Euler, the Bernoulli family and their environment" freely available online.
Euler's writings
During his life, Euler published about 560 writings. After his death in 1783, the Petersburg Academy published more of his manuscripts until 1830, increasing his number of publications to 756. Additional manuscripts were found later by his grandson Paul-Heinrich Fuss and published. Gustav Eneström established an inventory – the Eneström Index – between 1910 and 1913 listing 866 publications, namely E1–E866. Euler's writings are primarily in Latin, French, and German, though some are also in Russian and English. Previous attempts to compile all of Euler's writing had been made prior to the work of the Euler Committee.
The Committee has been publishing the 866 publications of Euler's work since 1911. The work was delayed by two world wars and economic issues. In the second part |
https://en.wikipedia.org/wiki/Ultrapolynomial | In mathematics, an ultrapolynomial is a power series in several variables whose coefficients are bounded in some specific sense.
Definition
Let and a field (typically or ) equipped with a norm (typically the absolute value). Then a function of the form is called an ultrapolynomial of class , if the coefficients satisfy for all , for some and (resp. for every and some ).
References
Mathematical analysis |
https://en.wikipedia.org/wiki/Cross-entropy%20benchmarking | Cross-entropy benchmarking (also referred to as XEB) is quantum benchmarking protocol which can be used to demonstrate quantum supremacy. In XEB, a random quantum circuit is executed on a quantum computer multiple times in order to collect a set of samples in the form of bitstrings . The bitstrings are then used to calculate the cross-entropy benchmark fidelity () via a classical computer, given by
,
where is the number of qubits in the circuit and is the probability of a bitstring for an ideal quantum circuit . If , the samples were collected from a noiseless quantum computer. If , then the samples could have been obtained via random guessing. This means that if a quantum computer did generate those samples, then the quantum computer is too noisy and thus has no chance of performing beyond-classical computations. Since it takes an exponential amount of resources to classically simulate a quantum circuit, there comes a point when the biggest supercomputer that runs the best classical algorithm for simulating quantum circuits can't compute the XEB. Crossing this point is known as achieving quantum supremacy; and after entering the quantum supremacy regime, XEB can only be estimated.
The Sycamore processor was the first to demonstrate quantum supremacy via XEB. Instances of random circuits with and 20 cycles were run to obtain an XEB of . Generating samples took 200 seconds on the quantum processor when it would have taken 10,000 years on Summit at the time of the experiment. Improvements in classical algorithms have shortened the runtime to about a week on Sunway TaihuLight thus collapsing Sycamore's claim to quantum supremacy. As of 2021, the latest demonstration of quantum supremacy by Zuchongzhi 2.1 with , 24 cycles and an XEB of holds. It takes around 4 hours to generate samples on Zuchonzhi 2.1 when it would take 10,000 years on Sunway.
See also
Boson sampling
References
Quantum information science
Quantum computing |
https://en.wikipedia.org/wiki/OwlCrate | OwlCrate is a web-based subscription service business specializing in monthly boxes shipped out internationally by mail, themed around books and book collecting. While OwlCrate is largely popular with book reviewers on social media, the service ships books to anybody within select available countries who places an order. Subscription boxes are largely themed around the fiction genres of science fiction and fantasy, with boxes designed both for young children and adolescent readers. Subscription boxes typically contain an exclusive (rare design) book cover with an author autograph, and a variety of surprise items associated with the book, including coffee mugs, t-shirts, pillow cases, lip balm, stickers, pinback buttons, jewellery and other paraphernalia.
History
OwlCrate was officially launched in February 2015 after months of development by its founders, Robert Madden and Korrina Ede. It began as a small home-based business, with the first book title included in the OwlCrate shipments being V. E. Schwab's fantasy novel A Darker Shade of Magic. Since 2015, OwlCrate has reportedly amassed thousands of subscribers, many of whom include Goodreads book reviewers, social media gurus, authors and book collectors.
In comparison, OwlCrate orders most of its non-book stock from independent artists, and continues to sell remaining stock from previous monthly boxes at a reduced price until the stock eventually runs out. One of the biggest assets that initially drew fans to the subscription service was that the OwlCrate versions of shipped books always have an exclusive cover and are autographed by the author, with most of these authors being traditionally-published by large publishing houses. According to a thesis study done through the Faculty of Communication, Art and Technology at Simon Fraser University, "exclusive covers vary book to book — some books will have a slight change in colour or font, some will have significant changes, and some will have a totally different |
https://en.wikipedia.org/wiki/RavenDB | RavenDB is an open-source fully ACID document-oriented database written in C#, developed by Hibernating Rhinos Ltd. It is cross-platform, supported on Windows, Linux, and Mac OS. RavenDB stores data as JSON documents and can be deployed in distributed clusters with master-master replication.
History
Originally named "Rhino DivanDB", RavenDB began in 2008 as a project by Oren Eini (aka Ayende Rahien) and is developed by Hibernating Rhinos Ltd. The company claims it was the first document database to run natively in the .NET Framework. It was an early document database to offer ACID guarantees.
In 2019, Hibernating Rhinos began offering RavenDB as a cloud service named RavenDB Cloud.
Version history
Red: Not supported
Green: Supported
System architecture
Data is stored as schemaless documents in JSON format. Documents are grouped into collections, with each document having exactly one collection.
Databases can be deployed on a distributed cluster of servers (called ‘nodes’) using multi-master replication. Some operations at the cluster level require a consensus of a majority of nodes; consensus is determined using an implementation of the Raft algorithm called Rachis. Tasks are distributed to the different nodes in a balanced way.
Versions 1.0 through 3.5 supported sharding, but versions 4.x do not.
RavenDB originally used the ESENT storage engine. Version 3.0 replaced it with a new open-source storage engine called Voron.
Clients are supported for C#, C++, Java, NodeJS, Python, Ruby, and Go.
Main features
Cluster-wide ACID Transactions - ACID transactions can be executed at the scope of a cluster (in addition to single node transactions). The transaction will only be persisted if it is confirmed by a consensus of nodes; if it is not, the transaction is cancelled and rolled back.
Distributed counters
Indexes and querying
Queries are expressed in LINQ or with a custom query language named RQL (stands for Raven Query Language) with syntax similar to SQ |
https://en.wikipedia.org/wiki/Cinematic%20virtual%20reality | Cinematic virtual reality (Cine-VR) is an immersive experience where the audience can look around in 360 degrees while hearing spatialized audio specifically designed to reinforce the belief that the audience is actually in the virtual environment rather than watching it on a two-dimensional screen. Cine-VR is different from traditional Virtual Reality which uses computer generated worlds and characters more akin to interactive gaming engines, while cine-VR uses live images captured thorough a camera which makes it more like film.
When storytellers began working in cine-VR, they applied many of the same cinematic narrative rules, but the technology demonstrated that VR can offer different possibilities that go beyond “traditional” cinema which will require new techniques and practices. Harrison Weber, journalist of Venturebeat, described cine-VR like this: "It’s a lot like film, only it puts the audience inside your story. With it, you can create entire worlds for your audience but none of the original rules of cinema apply. How do you create your art when all of your tools have changed?"
The Human Interface Technology (HIT) Lab at the University of Canterbury differentiates cine-VR from other content created with 360-degree cameras based on the content, likening the prefix “cinematic” to that of “narrative”. The HIT Lab requires cine-VR to be “narrative-based, instead of purely for novelty, entertainment, exploration, etc.”; the cine-VR experience can be a drama, a documentary, or a hybrid as long as the story contains a beginning, a middle, and an end. According to Ohio University's Game Research and Immersive Design (GRID) Lab, a cine-VR project differentiates itself from 360-degree video by using cinematic production techniques such as lighting design, sound design, scenic design, and blocking techniques (the latter two in the case of dramatic work).
The concepts of "immersion" and "presence" are central to cine-VR. The term presence is defined as "a sense |
https://en.wikipedia.org/wiki/Dimond%20ring | A Dimond ring or Dimond ring translator was an early type of computer memory, created in the early 1940s by T. L. Dimond at Bell Laboratories for Bell's #5 Crossbar Switch, a type of early telephone switch.
Structure
Large-diameter magnetic ferrite toroidal rings with solenoid windings, through which are threaded writing and reading wires.
Uses
It was used in the #5 Crossbar Switch and TXE (prior to version 4) telephone exchanges.
See also
Core rope memory, a later development
References
Computer memory
Non-volatile memory |
https://en.wikipedia.org/wiki/Empirical%20dynamic%20modeling | Empirical dynamic modeling (EDM) is a framework for analysis and prediction of nonlinear dynamical systems. Applications include population dynamics, ecosystem service, medicine, neuroscience, dynamical systems, geophysics, and human-computer interaction. EDM was originally developed by Robert May and George Sugihara. It can be considered a methodology for data modeling, predictive analytics, dynamical system analysis, machine learning and time series analysis.
Description
Mathematical models have tremendous power to describe observations of real-world systems. They are routinely used to test hypothesis, explain mechanisms and predict future outcomes. However, real-world systems are often nonlinear and multidimensional, in some instances rendering explicit equation-based modeling problematic. Empirical models, which infer patterns and associations from the data instead of using hypothesized equations, represent a natural and flexible framework for modeling complex dynamics.
Donald DeAngelis and Simeon Yurek illustrated that canonical statistical models are ill-posed when applied to nonlinear dynamical systems. A hallmark of nonlinear dynamics is state-dependence: system states are related to previous states governing transition from one state to another. EDM operates in this space, the multidimensional state-space of system dynamics rather than on one-dimensional observational time series. EDM does not presume relationships among states, for example, a functional dependence, but projects future states from localised, neighboring states. EDM is thus a state-space, nearest-neighbors paradigm where system dynamics are inferred from states derived from observational time series. This provides a model-free representation of the system naturally encompassing nonlinear dynamics.
A cornerstone of EDM is recognition that time series observed from a dynamical system can be transformed into higher-dimensional state-spaces by time-delay embedding with Takens's theorem. T |
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