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https://en.wikipedia.org/wiki/Pattern-Oriented%20Software%20Architecture | Pattern-Oriented Software Architecture is a series of software engineering books describing software design patterns.
POSA1
Architectural patterns
Layers
Pipes and filters
Blackboard
Broker
Model–View–Controller
Presentation–Abstraction–Control
Design patterns
Whole–Part
Master–Slave
Proxy
Command Processor
View Handler
Forwarder-Receiver
Client–Dispatcher–Server
Publisher–subscriber
POSA2
Service access and configuration patterns
Wrapper Facade
Component Configurator
Interceptor
Extension interface
Event handling patterns
Reactor
Proactor
Asynchronous Completion Token
Acceptor-Connector
Synchronization patterns
Scoped Locking
Strategized Locking
Thread-Safe Interface
Double-checked locking
Concurrency patterns
Active object
Monitor Object
Half-Sync/Half-Async
Leader/Followers
Thread-Specific Storage
POSA3
Resource acquisition
Lookup
Lazy acquisition
Eager acquisition
Resource lifecycle
Caching
Pooling
Coordinator
Resource Lifecycle Manager
Resource release
Leasing
Evictor
POSA4
Software architecture
Domain model
Layers
Model–View–Controller
Presentation–Abstraction–Control
Microkernel
Reflection
Pipes and filters
Shared repository
Blackboard
Domain object
Distribution Infrastructure
Message Channel
Message endpoint
Message translator
Message route
Publisher–subscriber
Broker
Client proxy
Requestor
Invoker
Client request handler
server request handler
Adaptation and execution
Bridge
Object Adapter
Chain of responsitiblity
Interpreter
Interceptor
Visitor
Decorator
Execute-Around Object
Template method
Strategy
Null Object
Wrapper Facade
Declarative component configuration
Resource management
Container
Component Configurator
Object manager
Lookup
Virtual Proxy
Lifecycle callback
Task coordinator
Resource pool
Resource cache
Lazy Acquisition
Eager Acquisition
Partial Acquisition
Activator
Evictor
Leasing
Automated Garbage Collection
Counting Handle
Abstract Fac |
https://en.wikipedia.org/wiki/Cyber-kinetic%20attack | A cyber-kinetic attack targets cyber-physical systems and causes direct or indirect physical damage, injury or death, or environmental impact solely through the exploitation of vulnerable information systems and processes. Notable attacks in this category in the recent past have targeted critical infrastructure facilities such as water treatment plants, nuclear power plants, oil refineries, and medical facilities.
Crossing the cyber-physical divide
In the early days of computing, security threats were typically limited attacks that caused destruction of data, or degraded access to computing systems or hardware. However, the last several decades have seen technologies—ranging from supervisory control and data acquisition (SCADA) to Internet of Things—which describe objects embedded with sensors and software and utilize the Internet to exchange data.
Such a system is termed as a Cyber-physical system. Such systems cross the traditional divide between purely in-computer systems (software) and real-life systems (physical systems), with algorithms being autonomously able to control physical systems.
One of the most notably cyber attacks that had a physical impact, causing significant degradation of a target system, were the Stuxnet and Aurora worms. The Stuxnet worm was first revealed in 2010 and specially targeted weaknesses in Programmable Logic Controllers (PLCs), devices in the SCADA category of systems. Though it was never positivity attributed, it is widely believed that the malicious software was developed jointly by the United States and Israel to disrupt the Iranian nuclear enrichment facility at Natanz. It has also been reported that Stuxnet and associated variants have infected more than 30,000 systems and had a lasting presence which was extremely difficult to eradicate and purify. Both malicious programs exploited Zero-Day attacks on Windows-based operating systems.
As computing crosses the cyber-physical barrier, there is significant effort spent o |
https://en.wikipedia.org/wiki/Algebra%20and%20Tiling | Algebra and Tiling: Homomorphisms in the Service of Geometry is a mathematics textbook on the use of group theory to answer questions about tessellations and higher dimensional honeycombs, partitions of the Euclidean plane or higher-dimensional spaces into congruent tiles. It was written by Sherman K. Stein and Sándor Szabó, and published by the Mathematical Association of America as volume 25 of their Carus Mathematical Monographs series in 1994. It won the 1998 Beckenbach Book Prize, and was reprinted in paperback in 2008.
Topics
The seven chapters of the book are largely self-contained, and consider different problems combining tessellations and algebra. Throughout the book, the history of the subject as well as the state of the art is discussed, and there are many illustrations.
The first chapter concerns a conjecture of Hermann Minkowski that, in any lattice tiling of a Euclidean space by unit hypercubes (a tiling in which a lattice of translational symmetries takes any hypercube to any other hypercube) some two cubes must meet face-to-face. This result was resolved positively by Hajós's theorem in group theory, but a generalization of this question to non-lattice tilings (Keller's conjecture) was disproved shortly before the publication of the book, in part by using similar group-theoretic methods.
Following this, three chapters concern lattice tilings by polycubes. The question here is to determine, from the shape of the polycube, whether all cubes in the tiling meet face-to-face or, equivalently, whether the lattice of symmetries must be a subgroup of the integer lattice. After a chapter on the general version of this problem, two chapters consider special classes of cross and "semicross"-shaped polycubes, both with regard to tiling and then, when these shapes do not tile, with regard to how densely they can be packed. In three dimensions, this is the notorious tripod packing problem.
Chapter five considers Monsky's theorem on the impossibility of parti |
https://en.wikipedia.org/wiki/Finite%20game | A finite game (sometimes called a founded game or a well-founded game) is a two-player game which is assured to end after a finite number of moves. Finite games may have an infinite number of possibilities or even an unbounded number of moves, so long as they are guaranteed to end in a finite number of turns.
Formal definition
William Zwicker defined a game, G, to be totally finite if it met the following five conditions:
Two players, I and II, move alternately, I going first. Each has complete knowledge of the other's moves.
There is no chance involved.
There are no ties (when a play of G is complete, there is one winner).
Every play ends after finitely many moves.
At any point in a play of G, there are but finitely many legal possibilities for the next move.
Examples
Tic Tac Toe
Chess
Checkers
Poker
The game where player one chooses any number and immediately wins (this is an example of a finite game with infinite possibilities)
The game where player one names any number N, then N moves pass with nothing happening before player one wins (this is an example of a finite game with an unbounded number of moves)
Supergame
A supergame is a variant of the finite game invented by William Zwicker. Zwicker defined a supergame to have the following rules:
"On the first move, I name any totally finite game G (called the subgame). The players then proceed to play G, with II playing the role of I while G is being played. The winner of the play of the subgame is declared to be the winner of the play of the supergame."
Zwicker notes that a supergame satisfies properties 1-4 of a totally finite game, but not property 5. He defines games of this type to be somewhat finite.
Hypergame paradox
A hypergame has the same rules as a super game except that I may name any somewhat finite game on the first move. The hypergame is closely related to the "hypergame paradox" a self-referential, set-theoretic paradox like Russell's paradox and Cantor's paradox.
The hypergame pa |
https://en.wikipedia.org/wiki/Microwave%20Journal | Microwave Journal (abbreviated as MWJ), , is an American magazine. It was established in 1958 as an industry technical journal covering RF and microwave applications for practicing engineers and scientists. It is indexed and abstracted in the Science Citation Index The print magazine reaches 50,000 qualified readers monthly (print and digital distribution). The journal articles are reviewed for impact, relevance and accuracy by their editorial review board making them the only industry journal that is peer reviewed in this market. It had an impact factor of 0.35 in 2018 according to the Web of Science Journal list. It also publishes in Chinese bi-monthly reaching 10,000 readers in China. In 2017, a sister journal covering high speed digital applications was launched called Signal Integrity Journal. Both magazines are free to qualified subscribers and are advertiser supported.
References
External links
microwavejournal.com/
Online magazines published in the United States
Electrical and electronic engineering magazines
Magazines established in 1958
Engineering magazines |
https://en.wikipedia.org/wiki/Hemolithin | Hemolithin (sometimes confused with the similar space polymer Hemoglycin) is a proposed protein containing iron and lithium, of extraterrestrial origin, according to an unpublished preprint. The result has not been published in any peer-reviewed scientific journal. The protein was purportedly found inside two CV3 meteorites, Allende and Acfer-086, by a team of scientists led by Harvard University biochemist Julie McGeoch. The report of the discovery was met with some skepticism and suggestions that the researchers had extrapolated too far from incomplete data.
Sources
The detected hemolithin protein was reported to have been found inside two CV3 meteorites Allende and Acfer 086. Acfer-086, where the complete molecule was detected rather than fragments (Allende), was discovered in Agemour, Algeria in 1990.
Structure
According to the researchers' mass spectrometry, hemolithin is largely composed of glycine and hydroxyglycine amino acids. The researchers noted that the protein was related to “very high extraterrestrial" ratios of Deuterium/Hydrogen (D/H); such high D/H ratios are not found anywhere on Earth, but are "consistent with long-period comets" and suggest, as reported, "that the protein was formed in the proto-solar disc or perhaps even earlier, in interstellar molecular clouds that existed long before the Sun’s birth".
A natural development of hemolithin may have started with glycine forming first, and then later linking with other glycine molecules into polymer chains, and later still, combining with iron and oxygen atoms. The iron and oxygen atoms reside at the end of the newly found molecule. The researchers speculate that the iron oxide grouping formed at the end of the molecule may be able to absorb photons, thereby enabling the molecule to split water (H2O) into hydrogen and oxygen and, as a result, produce a source of energy that might be useful to the development of life.
Exobiologist and chemist Jeffrey Bada expressed concerns about the possibl |
https://en.wikipedia.org/wiki/Reid%27s%20paradox%20of%20rapid%20plant%20migration | Reid's Paradox of Rapid Plant Migration or Reid's Paradox, describes the observation from the paleoecological record that plant ranges shifted northward, after the last glacial maximum, at a faster rate than the seed dispersal rates commonly occur. Rare long-distance seed dispersal events have been hypothesized to explain these fast migration rates, but the dispersal vector(s) are still unknown. The plant species' geographic range expansion rates are compared to the actualistic rates of seed dispersal using mathematical models, and are graphically visualized using dispersal kernels. These observations made in the paleontological record, which inspired Reid's Paradox, are from fossilized remains of plant parts, including needles, leaves, pollen, and seeds, that can be used to identify past shifts in plant species' ranges.
Reid's Paradox is named after Clement Reid, a paleobotanist, who made the principle observations from the paleobotanical record in Europe in 1899. His comparison of oak tree seed dispersal rates, and the observed range of oak trees from the fossil record, did not concur. Reid hypothesized that diffusion was not a possible explanation for the observed paradox, and supplemented his hypothesis by noting that birds were the likely cause of long range seed dispersal. Reid's Paradox has been subsequently documented across Europe and North America.
Dispersal kernels
Dispersal kernels are statistical models that represent the probability of seed dispersal from the source tree. Realistic biological data is required to complete the models. These data are used to accurately fill in variables such as seed number, seed size, and reproductive age. Depending on the plant species, the variables in the equation will change. In the years since Reid hypothesized the methods for seed dispersal, the models have gained more complex elements which attempt to resolve Reid's Paradox.
The dispersal of seeds from a parent tree are initially occurs as a normal distributio |
https://en.wikipedia.org/wiki/Direction-preserving%20function | In discrete mathematics, a direction-preserving function (or mapping) is a function on a discrete space, such as the integer grid, that (informally) does not change too drastically between two adjacent points. It can be considered a discrete analogue of a continuous function.
The concept was first defined by Iimura. Some variants of it were later defined by Yang, Chen and Deng, Herings, van-der-Laan, Talman and Yang, and others.
Basic concepts
We focus on functions , where the domain X is a finite subset of the Euclidean space . ch(X) denotes the convex hull of X.
There are many variants of direction-preservation properties, depending on how exactly one defines the "drastic change" and the "adjacent points". Regarding the "drastic change" there are two main variants:
Direction preservation (DP) means that, if x and y are adjacent, then for all : . In words: every component of the function f must not switch signs between adjacent points.
Gross direction preservation (GDP) means that, if x and y are adjacent, then . In words: the direction of the function f (as a vector) does not change by more than 90 degrees between adjacent points. Note that DP implies GDP but not vice versa.
Regarding the "adjacent points" there are several variants:
Hypercubic means that x and y are adjacent iff they are contained in some axes-parallel hypercube of side-length 1.
Simplicial means that x and y are adjacent iff they are vertices of the same simplex, in some triangulation of the domain. Usually, simplicial adjacency is much stronger than hypercubic adjacency; accordingly, hypercubic DP is much stronger than simplicial DP.
Specific definitions are presented below. All examples below are for dimensions and for X = { (2,6), (2,7), (3, 6), (3, 7) }.
Properties and examples
Hypercubic direction-preservation
A cell is a subset of that can be expressed by for some . For example, the square is a cell.
Two points in are called cell connected if there is a cell that c |
https://en.wikipedia.org/wiki/Introduction%20to%20Tropical%20Geometry | Introduction to Tropical Geometry is a book on tropical geometry, by Diane Maclagan and Bernd Sturmfels. It was published by the American Mathematical Society in 2015 as volume 161 of Graduate Studies in Mathematics.
Topics
The tropical semiring is an algebraic structure on the real numbers in which addition takes the usual place of multiplication, and minimization takes the usual place of addition. This combination of the two operations of addition and minimization comes up naturally, for instance, in the shortest path problem, where concatenating paths causes their distances to be added and where the shortest of two parallel paths is the one with minimum length, and where some shortest path algorithms can be interpreted as tropical matrix multiplication. Tropical geometry applies the machinery of algebraic geometry to this system by defining polynomials using addition and minimization in place of multiplication and addition (yielding piecewise linear functions), and studying the "roots" of these polynomials, the breakpoints where they fail to be linear. The field is named after the Brazilian adopted home of one of its pioneering researchers, Imre Simon. Although past work in the area has studied it through methods of enumerative combinatorics, this book instead is centered around explicit calculations related to the tropicalization of classical varieties. Although it is much more comprehensive than the two previous introductory books in this area by Itenberg et al.,
some topics in tropical geometry are (deliberately) omitted, including enumerative geometry and mirror symmetry.
The book has six chapters. Its first introduces the subject and gives an overview of some important result, after which the second chapter provides background material on non-Archimedean ordered field, algebraic varieties, convex polytopes, and Gröbner bases. Chapter three concerns tropical varieties, defined in several different ways, correspondences between classical varieties and their |
https://en.wikipedia.org/wiki/Gram%E2%80%93Euler%20theorem | In geometry, the Gram–Euler theorem, Gram-Sommerville, Brianchon-Gram or Gram relation (named after Jørgen Pedersen Gram, Leonhard Euler, Duncan Sommerville and Charles Julien Brianchon) is a generalization of the internal angle sum formula of polygons to higher-dimensional polytopes. The equation constrains the sums of the interior angles of a polytope in a manner analogous to the Euler relation on the number of d-dimensional faces.
Statement
Let be an -dimensional convex polytope. For each k-face , with its dimension (0 for vertices, 1 for edges, 2 for faces, etc., up to n for P itself), its interior (higher-dimensional) solid angle is defined by choosing a small enough -sphere centered at some point in the interior of and finding the surface area contained inside . Then the Gram–Euler theorem states: In non-Euclidean geometry of constant curvature (i.e. spherical, , and hyperbolic, , geometry) the relation gains a volume term, but only if the dimension n is even:Here, is the normalized (hyper)volume of the polytope (i.e, the fraction of the n-dimensional spherical or hyperbolic space); the angles also have to be expressed as fractions (of the (n-1)-sphere).
When the polytope is simplicial additional angle restrictions known as Perles relations hold, analogous to the Dehn-Sommerville equations for the number of faces.
Examples
For a two-dimensional polygon, the statement expands into:where the first term is the sum of the internal vertex angles, the second sum is over the edges, each of which has internal angle , and the final term corresponds to the entire polygon, which has a full internal angle . For a polygon with faces, the theorem tells us that , or equivalently, . For a polygon on a sphere, the relation gives the spherical surface area or solid angle as the spherical excess: .
For a three-dimensional polyhedron the theorem reads:where is the solid angle at a vertex, the dihedral angle at an edge (the solid angle of the corresponding lune is |
https://en.wikipedia.org/wiki/Pearls%20in%20Graph%20Theory | Pearls in Graph Theory: A Comprehensive Introduction is an undergraduate-level textbook on graph theory by Nora Hartsfield and Gerhard Ringel. It was published in 1990 by Academic Press with a revised edition in 1994 and a paperback reprint of the revised edition by Dover Books in 2003. The Basic Library List Committee of the Mathematical Association of America has suggested its inclusion in undergraduate mathematics libraries.
Topics
The "pearls" of the title include theorems, proofs, problems, and examples in graph theory. The book has ten chapters; after an introductory chapter on basic definitions, the remaining chapters material on graph coloring; Hamiltonian cycles and Euler tours; extremal graph theory; subgraph counting problems including connections to permutations, derangements, and Cayley's formula; graph labelings; planar graphs, the four color theorem, and the circle packing theorem; near-planar graphs; and graph embedding on topological surfaces.
The book also includes several unsolved problems such as the Oberwolfach problem on covering complete graphs by cycles, the characterization of magic graphs, and Ringel's Earth–Moon problem on coloring biplanar graphs.
Despite its subtitle "A comprehensive introduction", the book is short and its selection of topics reflects author Ringel's personal interests.. Important topics in graph theory that are not coveredinclude the symmetries of graphs, cliques, connections between graphs and linear algebra including adjacency matrices, algebraic graph theory and spectral graph theory, connectivity of a graph (or even biconnected components), Hall's marriage theorem, line graphs, interval graphs, and the theory of tournaments. There is also only one chapter of coverage on algorithms and real-world applications of graph theory. Also, the book omits "difficult or long proofs".
Audience and reception
The book is written as a lower-level undergraduate textbook and recommends that students using it have previously tak |
https://en.wikipedia.org/wiki/Edible%20gold | Edible gold is a particular type of gold authorized by the European Union and the United States as a food additive, under the code . It is used in haute cuisine as part of a trend towards extravagance in meals. It can be employed in foods and beverages such as in cookies decoration, wines or liquors; as sushi garnishment; or over ice cream. There are neither negative effects nor benefits from eating high-carat, food-grade gold since it is biologically inert, and it is usually suitable for use in food since it does not oxidize or corrode in moist air, unlike many other metals.
Technical specifications and production
Edible gold must fulfill the specifications from the applicable food safety standards. It has to be pure, to avoid any type of infections or perils for the body. Gold usually undergoes one of these processes: it could be hammered, or pounded and rolled, or just a leaf or powder. In the first case, the gold needs to reach the measure of about 1/8000 of a millimeter thick, in the second one it could be used as a normal leaf (the measure depends on the purpose) or smashed in powder.
History
Edible gold has been used since ancient times and can be found in many regions of the world and in different ages. The earliest evidence of the use of edible gold is among the ancient Egyptians, almost 5000 years ago, where the use of gold was well-known in many fields. The Egyptians used the gold for mental, bodily and spiritual purification because they believed it to have divine effects. The alchemists of Alexandria developed various medicines and elixirs with drinkable gold, which they believed restored and rejuvenated the body. It is believed that Cleopatra had body treatments with gold every night, such as having baths with gold and using a face mask of pure gold.
Ancient Egyptians were not the only ones to use gold as a decorative food and beverage garnish; it could also be found in the eastern countries such as Japan, China and India, mostly for medicine as m |
https://en.wikipedia.org/wiki/Corvette%20%28computer%29 | Corvette () was an 8-bit personal computer in the USSR, created for Soviet schools in 1980s. The first device was a homemade computer, created in 1985 by employees of the Moscow State University for their purposes (physics experiments). The first description was made in the magazine «Microprocessor tools and systems». The PC was named "ПК 8001" (21.08.1985).
Graphics
This computer had advanced graphic capabilities for its time. It has only one video mode which uses 4 planes: 3 graphic and 1 text. The graphic planes have 512x256 resolution. The text plane is capable to show 32x16 or 64x16 text using two sets of 256 ROM 8x16 characters for both modes. It possible to show 16 colors on screen. 8 colors are free and 8 additional colors can be used combining text symbols and pixels. Any logical color may be any physical color from 0 to 15 (RGBI). The graphic video RAM size is 192 KB (4 pages) or 48 KB (1 page). The text video RAM size is 1 KB which is 9-bit static RAM. The 9th bit is used as the reverse video attribute. There is no contention for access to video and processor RAM. The Corvette has a way to accelerate filling an area with a given color. It could be faster than the IBM PC AT with the EGA card for this task.
Sound
One channel of the Intel 8253 is used to generate sound.
Software
BASIC interpreter in ROM, fully compliant with the MSX standard, including all graphic commands (drawing points, lines, rectangles, filled rectangles, circles, ellipses, arcs, closed area filling, DRAW), working with integers, etc.
Operation systems MicroDOS (МикроДОС) and CP/M-80 (with floppy disk driver)
Text editor «Супертекст», «Микромир» (MIM), etc.
DBMS dBase II
Spreadsheet Microsoft Multiplan
Compilers for Fortran, Pascal, C, Ada, Forth, Lisp, PL/M, etc.
Software for education
Games («Berkut», PopCorn, Stalker, Dan Dare, Continental Circus, Deflector, «Treasure», «Winnie the Pooh», «Treasure Island», Super Tetris, Karate, etc.)
Educational computer te |
https://en.wikipedia.org/wiki/Symmetry%20in%20Mechanics | Symmetry in Mechanics: A Gentle, Modern Introduction is an undergraduate textbook on mathematics and mathematical physics, centered on the use of symplectic geometry to solve the Kepler problem. It was written by Stephanie Singer, and published by Birkhäuser in 2001.
Topics
The Kepler problem in classical mechanics is a special case of the two-body problem in which two point masses interact by Newton's law of universal gravitation (or by any central force obeying an inverse-square law). The book starts and ends with this problem, the first time in an ad hoc manner that represents the problem using a system of twelve variables for the positions and momentum vectors of the two bodies, uses the conservation laws of physics to set up a system of differential equations obeyed by these variables, and solves these equations. The second time through, it describes the positions and variables of the two bodies as a single point in a 12-dimensional phase space, describes the behavior of the bodies as a Hamiltonian system, and uses symplectic reductions to shrink the phase space to two dimensions before solving it to produce Kepler's laws of planetary motion in a more direct and principled way.
The middle portion of the book sets up the machinery of symplectic geometry needed to complete this tour. Topics covered in this part include manifolds, vector fields and differential forms, pushforwards and pullbacks, symplectic manifolds, Hamiltonian energy functions, the representation of finite and infinitesimal physical symmetries using Lie groups and Lie algebras, and the use of the moment map to relate symmetries to conserved quantities. In these topics, as well, concrete examples are central to the presentation.
Audience and reception
The book is written as a textbook for undergraduate mathematics and physics students, with many exercises, and it assumes that the students are already familiar with multivariable calculus and linear algebra, a significantly lower level of backgr |
https://en.wikipedia.org/wiki/Wells%20and%20Wellington%20affair | The Wells and Wellington affair was a dispute about the publication of three papers in the Australian Journal of Herpetology in 1983 and 1985. The periodical was established in 1981 as a peer-reviewed scientific journal focusing on the study of amphibians and reptiles (herpetology). Its first two issues were published under the editorship of Richard W. Wells, a first-year biology student at Australia's University of New England. Wells then ceased communicating with the journal's editorial board for two years before suddenly publishing three papers without peer review in the journal in 1983 and 1985. Coauthored by himself and high school teacher Cliff Ross Wellington, the papers reorganized the taxonomy of all of Australia's and New Zealand's amphibians and reptiles and proposed over 700 changes to the binomial nomenclature of the region's herpetofauna.
Members of the herpetological community reacted strongly to the pair's actions and eventually brought a case to the International Commission on Zoological Nomenclature to suppress the scientific names they had proposed. After four years of arguments, the commission opted not to vote on the case because it hinged largely on taxonomic arguments rather than nomenclatural ones, leaving some of Wells and Wellington's names available. The case's outcome highlighted the vulnerability to the established rules of biological nomenclature that desktop publishing presented. As of 2020, 24 of the specific names assigned by Wells and Wellington remained valid senior synonyms.
Background and publication
Australian Journal of Herpetology
The Australian Journal of Herpetology was a scientific journal specialising in herpetology. Its publisher, the Sydney-based Australian Herpetologists' League, was established to facilitate the journal's production. The journal's editorial board consisted of three Australian researchers: Harold Heatwole, an associate professor at the University of New England (UNE) in Armidale, New South Wales, Je |
https://en.wikipedia.org/wiki/Kathy%20Horadam | Kathryn Jennifer Horadam (born 1951) is an Australian mathematician known for her work on Hadamard matrices and related topics in mathematics and information security. She is an Emeritus Professor at the Royal Melbourne Institute of Technology (RMIT).
Life
Horadam is one of the three children of mathematicians Alwyn Horadam and Eleanor Mollie Horadam, and was born in 1951 in Armidale, New South Wales. She studied mathematics at Australian National University, earning a bachelor's degree in 1972 and completing her PhD in 1977. Her dissertation, The Homology of Groupnets, was supervised by Neville Smythe.
She worked for over 30 years at RMIT, becoming a professor of mathematics there in 1995. Additionally, she worked for three years in the Defence Science and Technology Group.
Book
Horadam is the author of the book Hadamard Matrices and Their Applications (Princeton University Press, 2007).
Recognition
Horadam became a fellow of the Institute of Combinatorics and its Applications in 1991 and of the Australian Mathematical Society in 2001. An international workshop on Hadamard matrices was held at RMIT in 2011 in honour of her 60th birthday, and papers from the workshop were published in 2013 as a special issue of the Australasian Journal of Combinatorics.
References
External links
1951 births
Living people
Australian mathematicians
Australian women mathematicians
Combinatorialists
Australian National University alumni
Academic staff of RMIT University |
https://en.wikipedia.org/wiki/Taking%20Sudoku%20Seriously | Taking Sudoku Seriously: The math behind the world's most popular pencil puzzle is a book on the mathematics of Sudoku. It was written by Jason Rosenhouse and Laura Taalman, and published in 2011 by the Oxford University Press. The Basic Library List Committee of the Mathematical Association of America has suggested its inclusion in undergraduate mathematics libraries. It was the 2012 winner of the PROSE Awards in the popular science and popular mathematics category.
Topics
The book is centered around Sudoku puzzles, using them as a jumping-off point "to discuss a broad spectrum of topics in mathematics". In many cases these topics are presented through simplified examples which can be understood by hand calculation before extending them to Sudoku itself using computers. The book also includes discussions on the nature of mathematics and the use of computers in mathematics.
After an introductory chapter on Sudoku and its deductive puzzle-solving techniques (also touching on Euler tours and Hamiltonian cycles), the book has eight more chapters and an epilogue. Chapters two and three discuss Latin squares, the thirty-six officers problem, Leonhard Euler's incorrect conjecture on Graeco-Latin squares, and related topics. Here, a Latin square is a grid of numbers with the same property as a Sudoku puzzle's solution of having each number appear once in each row and once in each column. They can be traced back to mathematics in medieval Islam, were studied recreationally by Benjamin Franklin, and have seen more serious application in the design of experiments and in error correction codes. Sudoku puzzles also constrain square blocks of cells to contain each number once, making a restricted type of Latin square called a gerechte design.
Chapters four and five concern the combinatorial enumeration of completed Sudoku puzzles, before and after factoring out the symmetries and equivalence classes of these puzzles using Burnside's lemma in group theory. Chapter six looks at |
https://en.wikipedia.org/wiki/International%20Journal%20of%20Geometry | The International Journal of Geometry is a peer-reviewed academic journal that covers Euclidean, Non-Euclidean and Discrete geometry.
It was established in 2012 with two volumes per year, and as of 2021 is published quarterly by the Department of Mathematics of the Vasile Alecsandri National College of Bacău.
It is abstracted and indexed among others by Zentralblatt MATH, MathSciNet, the Electronic Journals Library and Ebsco. Its founding editor-in-chief is Cătălin Barbu, a professor of mathematics at the Vasile Alecsandri National College of Bacău.
See also
Forum Geometricorum
References
External links
Mathematics journals
Open access journals
Academic journals established in 2012
English-language journals |
https://en.wikipedia.org/wiki/Crocheting%20Adventures%20with%20Hyperbolic%20Planes | Crocheting Adventures with Hyperbolic Planes is a book on crochet and hyperbolic geometry by Daina Taimiņa. It was published in 2009 by A K Peters, with a 2018 second edition by CRC Press.
Topics
The book is on the use of crochet to make physical surfaces with the geometry of the hyperbolic plane. The full hyperbolic plane cannot be embedded smoothly into three-dimensional space, but pieces of it can. Past researchers had made models of these surfaces out of paper, but Taimiņa's work is the first work to do so using textile arts. She had previously described these models in a research paper and used them as illustrations for an undergraduate geometry textbook, but this book describes more of the background for the project, makes it more widely accessible, and provides instructions for others to follow in making these models.
The book has nine chapters. The first chapter introduces the notion of the curvature of a surface, provides instructions for an introductory project in crocheting a patch of the hyperbolic plane, and provides an initial warning about the exponential growth in the area of this plane as a function of its radius, which will cause larger crochet projects to take a very long time to complete. Chapter two covers more concepts in the geometry of the hyperbolic plane, connecting them to crocheted models of the plane.
The next three chapters take a step back to look at the broader history of the topics discussed in the book: geometry and its connection to human arts and architecture in chapter 3, crochet in chapter 4, and non-Euclidean geometry in chapter 5. Chapters 6, 7, and 8 cover specific geometric objects with negatively-curved surfaces, including the pseudosphere, helicoid, and catenoid, investigate mathematical toys, and use these crocheted models "to explore otherwise hard to visualize objects". A final chapter covers the applications of hyperbolic geometry and its ongoing research interest.
Audience and reception
The book is written for a |
https://en.wikipedia.org/wiki/Integrally%20convex%20set | An integrally convex set is the discrete geometry analogue of the concept of convex set in geometry.
A subset X of the integer grid is integrally convex if any point y in the convex hull of X can be expressed as a convex combination of the points of X that are "near" y, where "near" means that the distance between each two coordinates is less than 1.
Definitions
Let X be a subset of .
Denote by ch(X) the convex hull of X. Note that ch(X) is a subset of , since it contains all the real points that are convex combinations of the integer points in X.
For any point y in , denote near(y) := {z in | |zi - yi| < 1 for all i in {1,...,n} }. These are the integer points that are considered "nearby" to the real point y.
A subset X of is called integrally convex if every point y in ch(X) is also in ch(X ∩ near(y)).
Example
Let n = 2 and let X = { (0,0), (1,0), (2,0), (2,1) }. Its convex hull ch(X) contains, for example, the point y = (1.2, 0.5).
The integer points nearby y are near(y) = {(1,0), (2,0), (1,1), (2,1) }. So X ∩ near(y) = {(1,0), (2,0), (2,1)}. But y is not in ch(X ∩ near(y)). See image at the right.
Therefore X is not integrally convex.
In contrast, the set Y = { (0,0), (1,0), (2,0), (1,1), (2,1) } is integrally convex.
Properties
Iimura, Murota and Tamura have shown the following property of integrally convex set.
Let be a finite integrally convex set. There exists a triangulation of ch(X) that is integral, i.e.:
The vertices of the triangulation are the vertices of X;
The vertices of every simplex of the triangulation lie in the same "cell" (hypercube of side-length 1) of the integer grid .
The example set X is not integrally convex, and indeed ch(X) does not admit an integral triangulation: every triangulation of ch(X), either has to add vertices not in X, or has to include simplices that are not contained in a single cell.
In contrast, the set Y = { (0,0), (1,0), (2,0), (1,1), (2,1) } is integrally convex, and indeed admits an in |
https://en.wikipedia.org/wiki/Discrete%20fixed-point%20theorem | In discrete mathematics, a discrete fixed-point is a fixed-point for functions defined on finite sets, typically subsets of the integer grid .
Discrete fixed-point theorems were developed by Iimura, Murota and Tamura, Chen and Deng and others. Yang provides a survey.
Basic concepts
Continuous fixed-point theorems often require a continuous function. Since continuity is not meaningful for functions on discrete sets, it is replaced by conditions such as a direction-preserving function. Such conditions imply that the function does not change too drastically when moving between neighboring points of the integer grid. There are various direction-preservation conditions, depending on whether neighboring points are considered points of a hypercube (HGDP), of a simplex (SGDP) etc. See the page on direction-preserving function for definitions.
Continuous fixed-point theorems often require a convex set. The analogue of this property for discrete sets is an integrally-convex set.
A fixed point of a discrete function f is defined exactly as for continuous functions: it is a point x for which f(x)=x.
For functions on discrete sets
We focus on functions , where the domain X is a nonempty subset of the Euclidean space . ch(X) denotes the convex hull of X.
Iimura-Murota-Tamura theorem: If X is a finite integrally-convex subset of , and is a hypercubic direction-preserving (HDP) function, then f has a fixed-point.
Chen-Deng theorem: If X is a finite subset of , and is simplicially direction-preserving (SDP), then f has a fixed-point.
Yang's theorems:
[3.6] If X is a finite integrally-convex subset of , is simplicially gross direction preserving (SGDP), and for all x in X there exists some g(x)>0 such that , then f has a zero point.
[3.7] If X is a finite hypercubic subset of , with minimum point a and maximum point b, is SGDP, and for any x in X: and , then f has a zero point. This is a discrete analogue of the Poincaré–Miranda theorem. It is a consequence of |
https://en.wikipedia.org/wiki/Lunar%20penetrometer | The lunar penetrometer was a spherical electronic tool that served to measure the load-bearing characteristics of the Moon in preparation for spacecraft landings. It was designed by NASA to be dropped onto the surface from a vehicle orbiting overhead and transmit information to the spacecraft. However, despite it being proposed for several lunar and planetary missions, the device was never actually fielded by NASA.
History
The lunar penetrometer was first developed in the early 1960s as part of NASA Langley Research Center’s Lunar Penetrometer Program. At the time, immense pressures from the ongoing Space Race caused NASA to shift its focus from conducting purely scientific lunar expeditions to landing a man on the Moon before the Russians. As a result, the Jet Propulsion Laboratory's lunar flight projects, Ranger and Surveyor, were reconfigured to provide direct support to Project Apollo.
One of the major problems that NASA faced in preparation for the Apollo Moon landing was the inability to determine the surface characteristics of the Moon with regard to spacecraft landings and post-landing locomotion of exploratory vehicles and personnel. While radio and optical technology situated on Earth at the time could make out large-scale characteristics such as the size and distribution of mountains and craters, there wasn't an Earth-based method of measuring small-scale features, such as the lunar surface texture and topographical details, with adequate resolution. In 1961, NASA's chief engineer Abe Silverstein proposed to the U.S. Congress that Project Ranger would help provide important data on the Moon's surface topography to facilitate the Apollo lunar landing. Once funding was provided to the Ranger program, Silverstein directed NASA laboratories to investigate potential instruments that could return information on the hardness of the lunar surface.
Introduced shortly after Silverstein's directive, the Lunar Penetrometer Program devised the development of an i |
https://en.wikipedia.org/wiki/Autogenous%20pressurization | Autogenous pressurization is the use of self-generated gaseous propellant to pressurize liquid propellant in rockets. Traditional liquid-propellant rockets have been most often pressurized with other gases, such as helium, which necessitates carrying the pressurant tanks along with the plumbing and control system to use it.
Autogenous pressurization has been operationally used on the Titan 34D, Space Shuttle, and Space Launch System. Autogenous pressurization is planned to be used on the Starship, New Glenn, Terran 1, ACES upper-stage and Rocket Lab's Neutron rocket.
Background
In autogenous pressurization, a small amount of propellant is heated until it turns to gas. That gas is then fed back into the liquid propellant tank it was sourced from. This helps keep the liquid propellant at the required pressure necessary to feed a rocket's engines. This is achieved through gas generators in a rocket's engine systems: tapped off from a gas generator; fed through a heat exchanger; or via electric heaters. Autogenous pressurization was already in use in the Titan booster by 1968 and had been tested with the RL10 engine, demonstrating its suitability for upper stage engines.
Traditionally, tank pressurization has been provided by a high pressure gas such as helium or nitrogen. Autogenous pressurization has been described as both less and more complex than using helium or nitrogen but it does provide significant advantages. The first is for long-term spaceflight and interplanetary missions such as going to and landing on Mars. Removing inert gases from usage allows engine firing in a non-pumping mode. The same vaporized gases can be used for mono or bi-propellant attitude control. The reuse of onboard oxidizer and fuel also reduces the contamination of combustibles by inert gases.
Risk reduction benefits come from reducing the requirement of high pressure storage vessels and completely isolating fuel and oxidizer systems, removing a possible failure path via the pressuri |
https://en.wikipedia.org/wiki/CAST-32A | CAST-32A, Multi-core Processors is a position paper, by the Certification Authorities Software Team (CAST). It is not official guidance, but is considered informational by certification authorities such as the FAA and EASA. A key point is that Multi-core processor "interference can affect execution timing behavior, including worst case execution time (WCET)."
The original document was published in 2014 by an "international group of certification and regulatory authority representatives." The current revision A was released in 2016. "The Federal Aviation Administration (FAA) and European Aviation Safety Agency (EASA) worked with industry to quantify a set of requirements and guidance that should be met to certify and use multi-core processors in civil aviation, described e.g. in the FAA CAST-32A Position Paper and the EASA Use of MULticore proCessORs in airborne Systems (MULCORS) research report."
For applicants certifying under EASA, AMC 20-193 has now superseded CAST-32A since its release on 21 January 2022. It is expected that the FAA will release its Advisory Circular AC 20-193 guidance in 2023, which is expected to be almost identical to AMC 20-193.
One of the first mixed-criticality multicore avionics systems is expected to be certified sometime in 2020. The objectives of the standard are applicable to software on multicore processors, including the operating system. However, the nature of the underlying processor hardware must be examined in detail to identify potential interference channels due to inter-core contention for shared resources. Verification that multicore interference channels have been mitigated can be accomplished through the use of interference generators i.e. software tuned to create a heavy usage pattern on a shared resource.
Objectives
The paper presents ten objectives that must be met for Design Assurance Level (DAL) A or B. Six of the objectives apply for DAL C. The paper does not apply for DAL D or E.
References
RTCA standards
Co |
https://en.wikipedia.org/wiki/DO-297 | DO-297, Integrated Modular Avionics (IMA) Development Guidance and Certification Considerations is one of the primary document by which certification authorities such as the FAA and EASA approve Integrated Modular Avionics (IMA) systems for flight. The FAA Advisory Circular (AC) 20-170 refers to DO-297.
Along with ARINC 653 and DO-248, the DO-297 standard guides "Safety of flight for
IMA systems" DO-297 provides specific guidance for the stakeholders, defining the following roles
platform and module suppliers
application suppliers
IMA system
integrator
certification applicant
maintenance organization
certification authority.
The DO-297 standard formalizes the use of more powerful computing hardware to host multiple software functions of mixed safety-criticality. IMA produces benefits of reduced Size, Weight, and Power (SWaP) by integrating into a single computing platform software functions that were formerly on separate (federated) computing systems. The standard describes how safety is maintained through the isolation provided by a partitioning environment, ensuring that independent functions cannot adversely impact one another's behavior.
History
The document was published by RTCA, Incorporated, in a joint effort with EUROCAE, completed in November 2005. The lessons learned in certifying early approaches to IMA in commercial aircraft such as the Boeing 787 Dreamliner and the Airbus A380 helped inform the development of the standard.
References
Computer standards
Safety engineering
RTCA standards
Avionics |
https://en.wikipedia.org/wiki/Call%20of%20Duty%3A%20Warzone | Call of Duty: Warzone was a free-to-play battle royale video game developed by Raven Software and Infinity Ward, and published by Activision. The game was released on March 10, 2020, for PlayStation 4, Windows, and Xbox One as a part of Call of Duty: Modern Warfare (2019) and was subsequently connected to 2020's Call of Duty: Black Ops Cold War and 2021's Call of Duty: Vanguard, but does not require purchase of any of the aforementioned titles. Warzone allows online multiplayer combat among 150 players and features both cross-platform play and cross-platform progression between the three aforementioned titles.
At launch, the game featured two main game modes: Battle Royale and Plunder. Warzone introduces a new in-game currency system that can be used at "Buy Stations" in and around the map. "Loadout Drops" are a key in-game object allowing players to access and switch between their customized classes and are obtainable through purchase with the Cash currency. Players may also use Cash to purchase items such as "killstreaks" and gas masks. Cash can be found by looting buildings and killing players that have cash on them. At launch, Warzone only offered Trios, a squad capacity of three players; Solos, Duos and Quads were eventually added to the game via post-launch updates.
Upon release, Warzone received generally favorable reviews from critics. Warzone was downloaded by six million people within 24 hours of its release; by April 2021, the game surpassed 100 million downloads.
A sequel, titled Call of Duty: Warzone 2.0, was released on November 16, 2022. A mobile version of Warzone is also in development. In June 2023, Activision announced that Call of Duty: Warzone servers would be shut down on September 21, 2023 to focus development on Warzone 2.0.
Gameplay
Warzone is the second main battle royale installment in the Call of Duty franchise, following the "Blackout" mode of Call of Duty: Black Ops 4. Warzone differs from Black Ops 4 by reducing reliance on equip |
https://en.wikipedia.org/wiki/Recursive%20islands%20and%20lakes | A recursive island or lake, also known as a nested island or lake, is an island or a lake that lies within a lake or an island.
For the purposes of defining recursion, small continental land masses such as Madagascar and New Zealand count as islands, while large continental land masses do not. Islands found within lakes in these countries are often recursive islands because the lake itself is located on an island.
Recursive islands
Islands in lakes
Only a few notable examples are given.
Islands in lakes on islands
There are nearly 1,000 islands in lakes on islands in Finland alone.
Islands in lakes on islands in lakes
Islands in lakes on islands in lakes on islands
Until 2020, Vulcan Point was an island that existed in Main Crater Lake on Volcano Island in Lake Taal on Luzon in the Philippines. Main Crater Lake evaporated during the 2020 Taal Volcano eruption, but the water in Taal Lake has returned and has a new island. Vulcan Point became a peninsula.
Islands in lakes on islands in lakes on islands in lakes
Only one lake is known to have such islands.
Moose Boulder was claimed to exist in the seasonal pond of Moose Flats on Ryan Island in Siskiwit Lake on Isle Royale in Lake Superior in the United States. In 2020, an expedition to the island found that it is potentially a hoax, along with the aforementioned seasonal pond.
Recursive lakes
Lakes on islands
Only a few notable examples are listed.
Lakes on islands in lakes
Lakes on islands in lakes on islands
Lakes on islands in lakes on islands in lakes
Only one such lake is known.
See also
List of endorheic basins
Volcanic crater lake
List of islands by area
List of lakes by area
List of islands by population
Notes
References
Coastal and oceanic landforms
Coastal geography
Lake islands
Lakes
Lists of islands
Recursion |
https://en.wikipedia.org/wiki/International%20Linear%20Algebra%20Society | The International Linear Algebra Society (ILAS) is a professional mathematical society organized to promote research and education in linear algebra, matrix theory and matrix computation. It serves the international community through conferences, publications, prizes and lectures. Membership in ILAS is open to all mathematicians and scientists interested in furthering its aims and participating in its activities.
History
ILAS was founded in 1989. Its genesis occurred at the Combinatorial Matrix Analysis Conference held at the University of Victoria in British Columbia, Canada, May 20–23, 1987, hosted by Dale Olesky and Pauline van den Driessche. ILAS was initially known as the International Matrix Group, founded in 1987. The founding officers of ILAS were Hans Schneider, President; Robert C. Thompson, Vice President; Daniel Hershkowitz, Secretary; and James R. Weaver, Treasurer.
ILAS Conferences
The inaugural meeting of ILAS took place at Brigham Young University (including one day at the Sundance Mountain Resort) in Provo, Utah, USA, from August 12–15, 1989. The organizing committee consisted of Wayne Barrett, Daniel Hershkowitz, Charles Johnson, Hans Schneider, and Robert C. Thompson. Much additional support came from Don Robinson, Chair of the BYU Mathematics Department, and James R. Weaver, ILAS Treasurer. The conference received support from Brigham Young University, the National Security Agency, and the National Science Foundation. There were 85 in attendance at the conference from 15 countries including Olga Taussky-Todd, a renowned mathematician in Matrix Theory. The proceedings of the Conference appeared in volume 150 of the journal Linear Algebra and Its Applications.
The 2nd ILAS conference was held in Lisbon, Portugal, August 3–7, 1992. The chair of the organizing committee was José Dias da Silva. There were 150 participants from 27 countries and the conference was supported by 11 different organizations. The proceedings of the conference |
https://en.wikipedia.org/wiki/Endangered%20species%20%28IUCN%20status%29 | Endangered species, as classified by the International Union for Conservation of Nature (IUCN), are species which have been categorized as very likely to become extinct in their known native ranges in the near future. On the IUCN Red List, endangered is the second-most severe conservation status for wild populations in the IUCN's schema after critically endangered. In 2012, the IUCN Red List featured 3,079 animal and 2,655 plant species as endangered worldwide. The figures for 1998 were 1,102 and 1,197 respectively.
IUCN Red List
The IUCN Red List is a list of species which have been assessed according to a
system of assigning a global conservation status. According to the latest system used by the IUCN, a species can be "Data Deficient" (DD) species – species for which more data and assessment is required before their situation may be determined – as well species comprehensively assessed by the IUCN's species assessment process. A species can be "Near Threatened" (NT) and "Least Concern" (LC), these are species which are considered to have relatively robust and healthy populations, according to the assessment authors. "Endangered" (EN) species lie between "Vulnerable" (VU) and "Critically Endangered" (CR) species. A species must adhere to certain criteria in order to be placed in any of the afore-mentioned conservation status categories, according to the assessment.
"Threatened" is a category including all those species determined to be Vulnerable, Endangered or Critically Endangered.
Although in general conversation the terms "endangered species" and "threatened species" may mean other things, for the purposes of the current IUCN system, the List uses the terms "endangered" and "threatened" to denote species to which certain criteria apply. Note older or other, such as national, status systems may use other criteria.
Some examples of species classified as endangered by the IUCN are listed below:
As more information becomes available, or as the conservat |
https://en.wikipedia.org/wiki/British%20Gear%20Association | The British Gear Association (BGA) is the trade body (association) that represents the manufacture of gear equipment and mechanical power transmission in the United Kingdom.
History
The BGA was formed in 1986 to replace the previous British Gear Manufacturers' Association, headquartered in central London; the BGMA worked with the Association of Hydraulic Equipment Manufacturers (which became the British Fluid Power Association) and the British Compressed Air Society. In the late 1980s, due to the level of research undertaken, West Germany was producing seven times the amount of transmission gearing than that of the UK.
The organisation was incorporated as a company in 1993.
Structure
The organisation is currently headquartered at Newcastle University. In 1993, the company moved to Staffordshire from Birmingham. Much research has been done in power transmission at the university's National Gear Metrology Laboratory (NGML).
The organisation is part of EUROTRANS, also known as the European Committee of Associations of Manufacturers of Gears and Transmission Parts, the European trade association for gear and transmission manufacturers, and works with Orgalim. Equivalent European organisations are VDMA in Germany, and Artema in France.
Function
The organisation represents companies that make transmission equipment, such as differentials for the automotive industry. It organises industry seminars and conferences; its annual conference is held in mid-November.
See also
American Gear Manufacturers Association
References
External links
BGA
1986 establishments in the United Kingdom
Automotive industry in the United Kingdom
Engineering societies based in the United Kingdom
Gears
Mechanical engineering organizations
Newcastle University
Organisations based in Tyne and Wear
Organizations established in 1986
Science and technology in Tyne and Wear
Trade associations based in the United Kingdom |
https://en.wikipedia.org/wiki/Nature%20Electronics | Nature Electronics is a monthly peer-reviewed scientific journal published by Nature Portfolio. It was established in 2018. The editor-in-chief is Owain Vaughan.
Abstracting and indexing
The journal is abstracted and indexed in:
Science Citation Index Expanded
Scopus
According to the Journal Citation Reports, the journal has a 2021 impact factor of 33.255, ranking it 1st out of 276 journals in the category "Engineering, Electrical & Electronic".
References
External links
English-language journals
electronics journals
Nature Research academic journals
Monthly journals
Online-only journals
Academic journals established in 2018 |
https://en.wikipedia.org/wiki/Audible%20Magic | Audible Magic Corporation (commonly Audible Magic) is a Los Gatos, California-based company that provides content identification services to social networks, record labels, music publishers, television studios, and movie studios. The company also provides digital platform music management services for Internet radio, subscription music services, on-demand streaming, and fitness and gaming applications. The services help companies identify and protect copyrighted content, manage rights and monetize media.
History
1999-2002
Audible Magic was founded in 1999 by Vance Ikezoye and Jim Schrempp. Their original goal was to create a service where radio listeners could call a number to identify a song that was playing and purchase it. Instead of using metadata and other digital descriptors, the company found a way to use the digital signature of the song itself to track and identify it.
In October 2000, Audible Magic acquired MuscleFish LLC, a developer of sound similarity and audio classification technologies.
In 2001, the company partnered with streaming audience size and demographics tracking company MeasureCast to provide the first verification and demographic reporting service for online advertisements.
In October 2002, Audible Magic signed a deal with its first major label, British music conglomerate EMI Recorded Music to use Audible Magic's audio fingerprinting technology to track licensed and unlicensed usage of EMI's song catalog.
2003-2007
In February 2003, the company announced the deployment of a new automated radio ad monitoring system for AM and FM radio stations across the country by New York City-based media monitoring company Video Monitoring Services of America (VMS). In October, Audible Magic signed a deal with Sony Music for Audible Magic's CopySense application, to block pirated content and pornography from being traded on peer-to-peer networks.
In October 2004, the company launched RepliCheck, an anti-piracy information system that identifies the |
https://en.wikipedia.org/wiki/Campenot%20chamber | A Campenot chamber is a three-chamber petri dish culture system devised by Robert Campenot to study neurons. Commonly used in neurobiology, the neuron soma or cell body is physically compartmentalized from its axons allowing for spatial segregation during investigation. This separation, typically done with a fluid impermeable barrier, can be used to study nerve growth factors (NGF). Neurons are particularly sensitive to environmental cues such as temperature, pH, and oxygen concentration which can affect their behavior.
The Campenot chamber can be used to study spatial and temporal axon guidance in both healthy controls and in cases of neuronal injury or neurodegeneration. Campenot concluded that neuron survival and growth depend on local nerve growth factors.
Structure
The Campenot chamber is made up of three chambers divided by Teflon fibers. These fibers are added to a petri dish coated in collagen with 20 scratches, spaced 200 μm apart, that become the parallel tracks for axons to grow. There is also a layer of grease that works to seal the Teflon to the neuron and separates the axon processes from the cell body. Refer to Side View of Campenot Chamber figure.
History of use
The uniqueness of the design allows for biochemical analysis and application of a stimulus at either distal or proximal ends. Campenot chambers have been used for a variety of studies including culturing of iPSC-derived motor neurons to isolate axonal RNA which can then be used for molecular analysis,,. The chamber has also been modified to study degeneration and apoptosis of cultured hippocampal neurons induced by amyloid beta. A modified 2-chamber system was used to examine the axonal transport of herpes simplex virus by examining the transmission of the virus from axon to epidermal cells. Through this study, the virus was found to undergo a specialized mode of viral transport, assembly and sensory neuron egress.
Recent techniques in lithography have made these chambers a more appea |
https://en.wikipedia.org/wiki/Target%20selection | Target selection is the process by which axons (nerve fibres) selectively target other cells for synapse formation. Synapses are structures which enable electrical or chemical signals to pass between nerves. While the mechanisms governing target specificity remain incompletely understood, it has been shown in many organisms that a combination of genetic and activity-based mechanisms govern initial target selection and refinement. The process of target selection has multiple steps that include Axon pathfinding when neurons extend processes to specific regions, cellular target selection when neurons choose appropriate partners in a target region from a multitude of potential partners, and subcellular target selection where axons often target particular regions of a partner neuron.
Description
As bundled axons finish navigating through various neural circuits during neural development, the growth cones must selectively target with which cells it will synapse. This can be particularly well observed in the visual and olfactory systems of organisms. In order to develop into a properly functioning nervous system, there must be an extremely high degree of accuracy in which cell the growth cone forms neural connections. Although the target cell selection must be highly accurate, the degree of specificity that the neural connectivity achieves varies based on the neuronal circuitry system. The target selection process of an axon to develop synaptic connections with specific cells can be broken down into multiple stages that are not necessarily confined to exact chronological order.
The stages of targeting include:
region specification
target cell specification
subcellular specification
synaptic refinement
Region specification
The first stage in target selection is specification of target region, a process known as Axon pathfinding. Growing neurites follow gradients of cell surface molecules that serve as chemoattractants and repellents to the growth cone. This perspect |
https://en.wikipedia.org/wiki/Cytokeratin%205/6%20antibodies | Cytokeratin 5/6 antibodies are antibodies that target both cytokeratin 5 and cytokeratin 6. These are used in immunohistochemistry, often called CK 5/6 staining, including the following applications:
Identifying basal cells or myoepithelial cells in the breast and prostate.
For breast pathology, also in distinguishing usual ductal hyperplasia (UDH) and papillary lesions (having a mosaic-like pattern) from ductal carcinoma in situ, which is usually negative. Cyclin D1 and CK5/6 staining could be used in concert to distinguish between the diagnosis of papilloma (Cyclin D1 < 4.20%, CK 5/6 positive) or papillary carcinoma (Cyclin D1 > 37.00%, CK 5/6 negative).
In the lung, distinguishing epithelioid mesothelioma (CK5/6 positive in 83%) from lung adenocarcinoma (CK5/6 negative in 85%).
References
External links
Recombinant Antibodies
Antibodies
Biochemistry
Immunohistochemistry |
https://en.wikipedia.org/wiki/Hiptmair%E2%80%93Xu%20preconditioner | In mathematics, Hiptmair–Xu (HX) preconditioners are preconditioners for solving and problems based on the auxiliary space preconditioning framework. An important ingredient in the derivation of HX preconditioners in two and three dimensions is the so-called regular decomposition, which decomposes a Sobolev space function into a component of higher regularity and a scalar or vector potential. The key to the success of HX preconditioners is the discrete version of this decomposition, which is also known as HX decomposition. The discrete decomposition decomposes a discrete Sobolev space function into a discrete component of higher regularity, a discrete scale or vector potential, and a high-frequency component.
HX preconditioners have been used for accelerating a wide variety of solution techniques, thanks to their highly scalable parallel implementations, and are known as AMS and ADS precondition. HX preconditioner was identified by the U.S. Department of Energy as one of the top ten breakthroughs in computational science in recent years. Researchers from Sandia, Los Alamos, and Lawrence Livermore National Labs use this algorithm for modeling fusion with magnetohydrodynamic equations. Moreover, this approach will also be instrumental in developing optimal iterative methods in structural mechanics, electrodynamics, and modeling of complex flows.
HX preconditioner for
Consider the following problem: Find such that
with .
The corresponding matrix form is
The HX preconditioner for problem is defined as
where is a smoother (e.g., Jacobi smoother, Gauss–Seidel smoother), is the canonical interpolation operator for space, is the matrix representation of discrete vector Laplacian defined on , is the discrete gradient operator, and is the matrix representation of the discrete scalar Laplacian defined on . Based on auxiliary space preconditioning framework, one can show that
where denotes the condition number of matrix .
In practice, inverti |
https://en.wikipedia.org/wiki/Algorithmic%20Geometry | Algorithmic Geometry is a textbook on computational geometry. It was originally written in the French language by Jean-Daniel Boissonnat and Mariette Yvinec, and published as Géometrie algorithmique by Edusciences in 1995. It was translated into English by Hervé Brönnimann, with improvements to some proofs and additional exercises, and published by the Cambridge University Press in 1998.
Topics
The book covers the theoretical background and analysis of algorithms in computational geometry, their implementation details, and their applications. It is grouped into five sections, the first of which covers background material on the design and analysis of algorithms and data structures, including computational complexity theory, and techniques for designing randomized algorithms. Its subsequent sections each consist of a chapter on the mathematics of a subtopic in this area, presented at the level of detail needed to analyze the algorithms, followed by two or three chapters on algorithms for that subtopic.
The topics presented in these sections and chapters include convex hulls and convex hull algorithms, low-dimensional randomized linear programming, point set triangulation for two- and three-dimensional data, arrangements of hyperplanes, of line segments, and of triangles, Voronoi diagrams, and Delaunay triangulations.
Audience and reception
The book can be used as a graduate textbook, or as a reference for computational geometry research. Reviewer Peter McMullen calls it "a welcome addition to the shelves of anyone interested in algorithmic geometry".
References
Computational geometry
Mathematics textbooks
1995 non-fiction books
1998 non-fiction books |
https://en.wikipedia.org/wiki/Protocol%20ossification | Protocol ossification is the loss of flexibility, extensibility and evolvability of network protocols. This is largely due to middleboxes that are sensitive to the wire image of the protocol, and which can interrupt or interfere with messages that are valid but which the middlebox does not correctly recognise. This is a violation of the end-to-end principle. Secondary causes include inflexibility in endpoint implementations of protocols.
Ossification is a major issue in Internet protocol design and deployment, as it can prevent new protocols or extensions from being deployed on the Internet, or place strictures on the design of new protocols; new protocols may have to be encapsulated in an already-deployed protocol or mimic the wire image of another protocol. Because of ossification, the Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) are the only practical choices for transport protocols on the Internet, and TCP itself has significantly ossified, making extension or modification of the protocol difficult.
Recommended methods of preventing ossification include encrypting protocol metadata, and ensuring that extension points are exercised and wire image variability is exhibited as fully as possible; remedying existing ossification requires coordination across protocol participants. QUIC is the first IETF transport protocol to have been designed with deliberate anti-ossification properties.
History
Significant ossification had set in on the Internet by 2005, with analyses of the problem also being published in that year; suggests that ossification was a consequence of the Internet attaining global scale and becoming the primary communication network.
Multipath TCP was the first extension to a core Internet protocol to deeply confront protocol ossification during its design.
The IETF created the Transport Services (taps) working group in 2014. It has a mandate to mitigate ossification at the transport protocol layer.
QUIC is the first IET |
https://en.wikipedia.org/wiki/IEEE%20Transactions%20on%20Electromagnetic%20Compatibility | IEEE Transactions on Electromagnetic Compatibility is a peer-reviewed scientific journal published bimonthly by the IEEE Electromagnetic Compatibility Society. It covers electromagnetic compatibility (EMC) and electromagnetic interference, as well as computational electromagnetics and signal integrity methods for EMC problems. Its current editor-in-chief is Tzong-Lin Wu, professor of electrical engineering at National Taiwan University.
The journal was founded in 1959 under the name IRE Transactions on Radio Frequency Interference by Institute of Radio Engineers. According to the Journal Citation Reports, the journal has a 2020 impact factor of 2.006.
References
External links
Electromagnetic Compatibility, IEEE Transactions on
Electromagnetism journals
English-language journals
Academic journals established in 1959
Bimonthly journals |
https://en.wikipedia.org/wiki/Zen%203 | Zen 3 is the codename for a CPU microarchitecture by AMD, released on November 5, 2020. It is the successor to Zen 2 and uses TSMC's 7 nm process for the chiplets and GlobalFoundries's 14 nm process for the I/O die on the server chips and 12 nm for desktop chips. Zen 3 powers Ryzen 5000 mainstream desktop processors (codenamed "Vermeer") and Epyc server processors (codenamed "Milan"). Zen 3 is supported on motherboards with 500 series chipsets; 400 series boards also saw support on select B450 / X470 motherboards with certain BIOSes. Zen 3 is the last microarchitecture before AMD switched to DDR5 memory and new sockets, which are AM5 for the desktop "Ryzen" chips alongside SP5 and SP6 for the EPYC server platform. According to AMD, Zen 3 has a 19% higher instructions per cycle (IPC) on average than Zen 2.
On April 1, 2022, AMD released the new Ryzen 6000 series for the laptop, using an improved Zen 3+ architecture. On April 20, 2022, AMD also released the Ryzen 7 5800X3D desktop processor, which increases the single threading performance by another 15% in gaming by using, for the first time in a PC product, 3D vertically stacked L3 cache.
Features
Zen 3 is a significant incremental improvement over its predecessors, with an IPC increase of 19%, and being capable of reaching higher clock speeds.
Like Zen 2, Zen 3 is composed of up to 2 core complex dies (CCD) along with a separate IO die containing the I/O components. A Zen 3 CCD is composed of a single core complex (CCX) containing 8 CPU cores and 32MB of shared L3 cache, this is in contrast to Zen 2 where each CCD is composed of 2 CCX, each containing 4 cores each as well as 16MB of L3 cache. The new configuration allows all 8 cores of the CCX to directly communicate with each other and the L3 Cache instead of having to use the IO die through the Infinity Fabric.
Zen 3 (along with AMD's RDNA2 GPUs) were also the first implementation of Resizable BAR, an optional feature introduced in PCIe2.0, that was branded |
https://en.wikipedia.org/wiki/Raymond%20Andrew | Edward Raymond Andrew FRS FRSE (27 June 1921 – 27 May 2001) was a 20th-century British scientist who was a pioneer of nuclear magnetic resonance. He was a primary figure in the development and creation of the world's first MRI scanner.
Life
He was born in Boston, Lincolnshire on 27 June 1921 the only child of English parents of Scots descent. He was educated at Wellingborough School where he was head boy. He then won a place at Christ's College, Cambridge on a Natural Science Tripos from 1939 to 1942 under C. P. Snow, Lawrence Bragg, Norman Feather and David Shoenberg.
From 1942 to 1945, during the Second World War he was Scientific Officer at the Air Defence Research and Development Establishment in Malvern studying the effects of gun flashes on radar.
In 1945 he returned to Cambridge as a research student at Pembroke College and at the Cavendish Laboratory. Here he worked with David Shoenberg on superconductors, gaining a doctorate (PhD) in 1948. He then went to Harvard University for a year to work on nuclear magnetic resonance with Ed Purcell and Bersohn, also working on the Pake doublet.
He returned to Britain in 1949 to work with Jack Allen FRS at the Cavendish. Colleagues on the NMR project included Bob Eades, Dan Hyndman and Alwyn Rushworth. His students here included Waldo Hinshaw.
In March 1952 he was elected a Fellow of the Royal Society of Edinburgh.
In 1954 he became professor of physics at the University of North Wales in Bangor. Here he founded the British Radio-Frequency Spectroscopy Group (BRSG).
In 1964 he moved to a chair at the University of Nottingham in place of Prof L. F. Bates. His work here included the development of the MRI scanner from 1975 to 1977. In 1978 their success led to the development of the whole-body MRI scanner.
After 19 years in Nottingham he moved to the University of Florida in Gainesville as Graduate Professor of Radiology, Physics and Nuclear Engineering.
In 1984 he was elected a Fellow of the Royal Society of Lo |
https://en.wikipedia.org/wiki/Introduction%20to%20the%20Theory%20of%20Error-Correcting%20Codes | Introduction to the Theory of Error-Correcting Codes is a textbook on error-correcting codes, by Vera Pless. It was published in 1982 by John Wiley & Sons, with a second edition in 1989 and a third in 1998. The Basic Library List Committee of the Mathematical Association of America has rated the book as essential for inclusion in undergraduate mathematics libraries.
Topics
This book is mainly centered around algebraic and combinatorial techniques for designing and using error-correcting linear block codes. It differs from previous works in this area in its reduction of each result to its mathematical foundations, and its clear exposition of the results follow from these foundations.
The first two of its ten chapters present background and introductory material, including Hamming distance, decoding methods including maximum likelihood and syndromes, sphere packing and the Hamming bound, the Singleton bound, and the Gilbert–Varshamov bound, and the Hamming(7,4) code. They also include brief discussions of additional material not covered in more detail later, including information theory, convolutional codes, and burst error-correcting codes. Chapter 3 presents the BCH code over the field , and Chapter 4 develops the theory of finite fields more generally.
Chapter 5 studies cyclic codes and Chapter 6 studies a special case of cyclic codes, the quadratic residue codes. Chapter 7 returns to BCH codes. After these discussions of specific codes, the next chapter concerns enumerator polynomials, including the MacWilliams identities, Pless's own power moment identities, and the Gleason polynomials.
The final two chapters connect this material to the theory of combinatorial designs and the design of experiments, and include material on the Assmus–Mattson theorem, the Witt design, the binary Golay codes, and the ternary Golay codes.
The second edition adds material on BCH codes, Reed–Solomon error correction, Reed–Muller codes, decoding Golay codes, and "a new, simple comb |
https://en.wikipedia.org/wiki/Amstrad%20CPC%20character%20set | The Amstrad CPC character set (alternatively known as the BASIC graphics character set) is the character set used in the Amstrad CPC series of 8-bit personal computers when running BASIC (the default mode, until it boots into CP/M). This character set existed in the built-in "lower" ROM chip. It is based on ASCII-1967, with the exception of character 0x5E which is the up arrow instead of the circumflex, as it is in ASCII-1963, a feature shared with other character sets of the time. Apart from the standard printable ASCII range (0x20-0x7e), it is completely different from the Amstrad CP/M Plus character set. The BASIC character set had symbols of particular use in games and home computing, while the CP/M Plus character reflected the International and Business flavor of the CP/M Plus environment. This character set is represented in Unicode (excluding 0xEF, 0xFC, and 0xFD) as of the March 2020 release of Unicode 13.0, which added symbols for legacy computing.
Character set
Control characters
Each of the characters in the C0 character range (0x00-0x1F) had a special function.
References
Character sets |
https://en.wikipedia.org/wiki/Computability%20in%20Analysis%20and%20Physics | Computability in Analysis and Physics is a monograph on computable analysis by Marian Pour-El and J. Ian Richards. It was published by Springer-Verlag in their Perspectives in Mathematical Logic series in 1989, and reprinted by the Association for Symbolic Logic and Cambridge University Press in their Perspectives in Logic series in 2016.
Topics
The book concerns computable analysis, a branch of mathematical analysis founded by Alan Turing and concerned with the computability of constructions in analysis. This area is connected to, but distinct from, constructive analysis, reverse mathematics, and numerical analysis. The early development of the field was summarized in a book by Oliver Aberth, Computable Analysis (1980), and Computability in Analysis and Physics provides an update, incorporating substantial developments in this area by its authors. In contrast to the Russian school of computable analysis led by Andrey Markov Jr., it views computability as a distinguishing property of mathematical objects among others, rather than developing a theory that concerns only computable objects.
After an initial section of the book, introducing computable analysis and leading up to an example of John Myhill of a computable continuously differentiable function whose derivative is not computable, the remaining two parts of the book concerns the authors' results. These include the results that, for a computable self-adjoint operator, the eigenvalues are individually computable, but their sequence is (in general) not; the existence of a computable self-adjoint operator for which 0 is an eigenvalue of multiplicity one with no computable eigenvectors; and the equivalence of computability and boundedness for operators. The authors' main tools include the notions of a computability structure, a pair of a Banach space and an axiomatically-characterized set of its sequences, and of an effective generating set, a member of the set of sequences whose linear span is dense in the space |
https://en.wikipedia.org/wiki/Mac%20OS%20Gujarati | Mac OS Gujarati is a character set developed by Apple Inc. based on IS 13194:1991 (ISCII-91).
Code page layout
The following table shows the Mac OS Gujarati encoding. Each character is shown with its equivalent Unicode code point. Only the second half of the table (code points 128–255) is shown, the first half (code points 0–127) being the same as Mac OS Roman.
Byte pairs and ISCII-related features are described in the mapping file.
References
Character sets
Gujarati |
https://en.wikipedia.org/wiki/Mac%20OS%20Gurmukhi | Mac OS Gurmukhi is a character set developed by Apple Inc., based on IS 13194:1991 (ISCII-91).
Code page layout
The following table shows the Mac OS Gurmukhi encoding. Each character is shown with its equivalent Unicode code point. Only the second half of the table (code points 128–255) is shown, the first half (code points 0–127) being the same as Mac OS Roman.
Byte pairs and ISCII-related features are described in the mapping file.
References
Character sets
Gurmukhi |
https://en.wikipedia.org/wiki/Code%20of%20the%20Quipu | Code of the Quipu is a book on the Inca system of recording numbers and other information by means of a quipu, a system of knotted strings. It was written by mathematician Marcia Ascher and anthropologist Robert Ascher, and published as Code of the Quipu: A Study in Media, Mathematics, and Culture by the University of Michigan Press in 1981. Dover Books republished it with corrections in 1997 as Mathematics of the Incas: Code of the Quipu. The Basic Library List Committee of the Mathematical Association of America has recommended its inclusion in undergraduate mathematics libraries.
Topics
The book describes (necessarily by inference, as there is no written record beyond the quipu the themselves) the uses of the quipu, for instance in accounting and taxation. Although 400 quipu are known to survive, the book's study is based on a selection of 191 of them, described in a companion databook. It analyzes the mathematical principles behind the use of the quipu, including a decimal form of positional notation, the concept of zero, rational numbers, and arithmetic, and the way the spatial relations between the strings of a quipu recorded hierarchical and categorical information.
It argues that beyond its use in recording numbers, the quipu acted as a method for planning for future events, and as a writing system for the Inca, and that it provides a tangible representation of "insistence", the thematic concerns in Inca culture for symmetry and spatial and hierarchical connections.
The initial chapters of the book provide an introduction to Inca society and the physical organization of a quipu (involving the colors, size, direction, and hierarchy of its strings), and discussions of repeated themes in Inca society and of the place of the quipu and its makers in that society. Later chapters discuss the mathematical structure of the quipu and of the information it stores, with reference to similarly-structured data in modern society and exercises that ask students to constr |
https://en.wikipedia.org/wiki/Calendrical%20Calculations | Calendrical Calculations is a book on calendar systems and algorithms for computers to convert between them. It was written by computer scientists Nachum Dershowitz and Edward Reingold and published in 1997 by the Cambridge University Press. A second "millennium" edition with a CD-ROM of software was published in 2001, a third edition in 2008, and a fourth "ultimate" edition in 2018.
Topics
There have been many different calendars in different societies, and there is much difficulty in converting between them, largely because of the impossibility of reconciling the irrational ratios of the daily, monthly, and yearly astronomical cycle lengths using integers. The 14 calendars discussed in the first edition of the book included the Gregorian calendar, ISO week date, Julian calendar, Coptic calendar, Ethiopian calendar, Islamic calendar, modern Iranian calendar, Baháʼí calendar, French Republican calendar, old and modern Hindu calendars, Maya calendar, and modern Chinese calendar. Later editions expanded it to many more calendars. They are divided into two groups: "arithmetical" calendars, whose calculations can be performed purely mathematically, independently from the positions of the moon and sun, and "astronomical" calendars, based in part on those positions.
The authors design individual calendrical calculation algorithms for converting each of these calendars to and from a common format, the Rata Die system of days numbered from January 1 of the (fictional) Gregorian year 1. Combining these methods allows the conversion between any two of the calendars. One of the innovations of the book is the use of clever coding to replace tables of values of mildly-irregular sequences, such as the numbers of days in a month. The authors also discuss the history of the calendars they describe, analyze their accuracy with respect to the astronomical events that they were designed to model, and point out important days in the year of each calendar. An appendix includes full do |
https://en.wikipedia.org/wiki/Harley%20McAdams | Harley H. McAdams (born 1938, Liberty, Texas) is an American physicist, microbial geneticist, and developmental biologist. McAdams and his collaborators have published foundational insights on the nature of genetic regulatory logic and cell biology, the molecular basis for inevitable random variation levels of protein production between different cells, and genetic logic circuits that control the bacterial cell cycle. McAdams is married to Lucy Shapiro. They were jointly awarded the 2009 John Scott Medal for “bringing the methods of electrical circuit analysis to the description of genetic networks of the simple bacterium Caulobacter.”
McAdams, a professor emeritus in the Department of Developmental Biology in the Stanford University School of Medicine, holds undergraduate and graduate degrees in physics from Texas A&M University (BS), the University of Illinois (Urbana) (MS), and Rice University (MA, PhD). He is a fellow of the American Society for Microbiology.
References
Living people
21st-century American biologists
Rice University alumni
1938 births
20th-century American biologists
Stanford University Department of Biology faculty
Grainger College of Engineering alumni
Developmental biologists
Scientists from Texas
People from Liberty, Texas
American geneticists
American microbiologists
21st-century American physicists
20th-century American physicists |
https://en.wikipedia.org/wiki/Slicing%20the%20Truth | Slicing the Truth: On the Computability Theoretic and Reverse Mathematical Analysis of Combinatorial Principles is a book on reverse mathematics in combinatorics, the study of the axioms needed to prove combinatorial theorems. It was written by Denis R. Hirschfeldt, based on a course given by Hirschfeldt at the National University of Singapore in 2010, and published in 2014 by World Scientific, as volume 28 of the Lecture Notes Series of the Institute for Mathematical Sciences, National University of Singapore.
Topics
The book begins with five chapters that discuss the field of reverse mathematics, which has the goal of classifying mathematical theorems by the axiom schemes needed to prove them, and the big five subsystems of second-order arithmetic into which many theorems of mathematics have been classified. These chapters also review some of the tools needed in this study, including computability theory, forcing, and the low basis theorem.
Chapter six, "the real heart of the book", applies this method to an infinitary form of Ramsey's theorem: every edge coloring of a countably infinite complete graph or complete uniform hypergraph, using finitely many colors, contains a monochromatic infinite induced subgraph. The standard proof of this theorem uses the arithmetical comprehension axiom, falling into one of the big five subsystems, ACA0. However, as David Seetapun originally proved, the version of the theorem for graphs is weaker than ACA0, and it turns out to be inequivalent to any one of the big five subsystems. The version for uniform hypergraphs of fixed order greater than two is equivalent to ACA0, and the version of the theorem stated for all numbers of colors and all orders of hypergraphs simultaneously is stronger than ACA0.
Chapter seven discusses conservative extensions of theories, in which the statements of a powerful theory (such as one of the forms of second-order arithmetic) that are both provable in that theory and expressible in a weaker theo |
https://en.wikipedia.org/wiki/45-bit%20computing |
Examples
Computers designed with 45-bit words are quite rare. One 45-bit computer was the Soviet Almaz ("") computer.
See also
60-bit computing
References
Data unit
Soviet computer systems |
https://en.wikipedia.org/wiki/Rayleigh%20theorem%20for%20eigenvalues | In mathematics, the Rayleigh theorem for eigenvalues pertains to the behavior of the solutions of an eigenvalue equation as the number of basis functions employed in its resolution increases. Rayleigh, Lord Rayleigh, and 3rd Baron Rayleigh are the titles of John William Strutt, after the death of his father, the 2nd Baron Rayleigh. Lord Rayleigh made contributions not just to both theoretical and experimental physics, but also to applied mathematics. The Rayleigh theorem for eigenvalues, as discussed below, enables the energy minimization that is required in many self-consistent calculations of electronic and related properties of materials, from atoms, molecules, and nanostructures to semiconductors, insulators, and metals. Except for metals, most of these other materials have an energy or a band gap, i.e., the difference between the lowest, unoccupied energy and the highest, occupied energy. For crystals, the energy spectrum is in bands and there is a band gap, if any, as opposed to energy gap. Given the diverse contributions of Lord Rayleigh, his name is associated with other theorems, including Parseval's theorem. For this reason, keeping the full name of "Rayleigh Theorem for Eigenvalues" avoids confusions.
Statement of the theorem
The theorem, as indicated above, applies to the resolution of equations called eigenvalue equations. i.e., the ones of the form HѰ = λѰ, where H is an operator, Ѱ is a function and λ is number called the eigenvalue. To solve problems of this type, we expand the unknown function Ѱ in terms of known functions. The number of these known functions is the size of the basis set. The expansion coefficients are also numbers. The number of known functions included in the expansion, the same as that of coefficients, is the dimension of the Hamiltonian matrix that will be generated. The statement of the theorem follows.
Let an eigenvalue equation be solved by linearly expanding the unknown function in terms of N known functions. Let the |
https://en.wikipedia.org/wiki/Journal%20of%20Biological%20Dynamics | The Journal of Biological Dynamics is a peer-reviewed open access scientific journal covering mathematical modeling in the field of biology. It was established in 2007 and is published continuously by Taylor & Francis. The editors-in-chief are J. M. Cushing (University of Arizona) and Saber N. Elaydi (Trinity University). According to the Journal Citation Reports, the journal has a 2018 impact factor of 1.642.
References
External links
Academic journals established in 2007
English-language journals
Continuous journals
Taylor & Francis academic journals
Open access journals
Mathematical and theoretical biology
Biology journals |
https://en.wikipedia.org/wiki/Sacred%20Mathematics | Sacred Mathematics: Japanese Temple Geometry is a book on Sangaku, geometry problems presented on wooden tablets as temple offerings in the Edo period of Japan. It was written by Fukagawa Hidetoshi and Tony Rothman, and published in 2008 by the Princeton University Press. It won the PROSE Award of the Association of American Publishers in 2008 as the best book in mathematics for that year.
Topics
The book begins with an introduction to Japanese culture and how this culture led to the production of Sangaku tablets, depicting geometry problems, their presentation as votive offerings at temples, and their display at the temples. It also includes a chapter on the Chinese origins of Japanese mathematics, and a chapter on biographies of Japanese mathematicians from the time.
The Sangaku tablets illustrate theorems in Euclidean geometry, typically involving circles or ellipses, often with a brief textual explanation. They are presented as puzzles for the viewer to prove, and in many cases the proofs require advanced mathematics. In some cases, booklets providing a solution were included separately, but in many cases the original solution has been lost or was never provided. The book's main content is the depiction, explanation, and solution of over 100 of these Sangaku puzzles, ranked by their difficulty, selected from over 1800 catalogued Sangaku and over 800 surviving examples. The solutions given use modern mathematical techniques where appropriate rather than attempting to model how the problems would originally have been solved.
Also included is a translation of the travel diary of Japanese mathematician Yamaguchi Kanzan (or Kazu), who visited many of the temples where these tablets were displayed and in doing so built a collection of problems from them. The final three chapters provide a scholarly appraisal of precedence in mathematical discoveries between Japan and the west, and an explanation of the techniques that would have been available to Japanese problem-s |
https://en.wikipedia.org/wiki/Laver%27s%20theorem | Laver's theorem, in order theory, states that order embeddability of countable total orders is a well-quasi-ordering. That is, for every infinite sequence of totally-ordered countable sets, there exists an order embedding from an earlier member of the sequence to a later member. This result was previously known as Fraïssé's conjecture, after Roland Fraïssé, who conjectured it in 1948; Richard Laver proved the conjecture in 1971. More generally, Laver proved the same result for order embeddings of countable unions of scattered orders.
In reverse mathematics, the version of the theorem for countable orders is denoted FRA (for Fraïssé) and the version for countable unions of scattered orders is denoted LAV (for Laver). In terms of the "big five" systems of second-order arithmetic, FRA is known to fall in strength somewhere between the strongest two systems, -CA0 and ATR0, and to be weaker than -CA0. However, it remains open whether it is equivalent to ATR0 or strictly between these two systems in strength.
See also
Dushnik–Miller theorem
References
Order theory |
https://en.wikipedia.org/wiki/Keysmash | A keysmash (alternatively key smash or keyboard smash) is internet slang for the typing out of a random sequence of letters on a computer keyboard or touchscreen, often to express intense emotion. Gaining popularity since 2019, the term is often used to convey intense or indescribable emotions (such as frustration or excitement), and it can also be used as an expression of laughter.
History and usage
Dictionary.com lists keysmash as both a noun ("I typed a keysmash") and a verb ("I keysmashed a response"), dating the term to sometime between 1995 and 2000.
The first commonly used variation of "keysmashing" appeared and possibly first majorly originated from the Turkish internet sphere, where the so-called "random laugh", or "random" (as said in Turkish) has been in use since at least the mid-2000s in online forums, e.g ekşisözlük, to convey and portray a more genuine laughter—implying a user "laughed so hard that they fell on (rolled over) their keyboard".
The term is often associated with Stan Twitter users, VSCO culture, and members of the LGBT community, but is not restricted to these groups. Keysmashing has occasionally been referred to as "gay keysmashing" due to this association.
Variations
Keysmashes of any kind can usually be seen in either all lower case, or all upper case letters. Despite how random many keysmashes may appear to be, there are societal patterns and norms to what a keysmash is supposed to look like. Keysmashes that fail to visually appeal to the ones typing them have a chance of being completely rewritten or having a few minor adjustments made (i.e. removing or adding new characters). The overall format of a keysmash is one that is usually dependent on the type of device or keyboard that is being used and therefore makes different keyboard layouts more acceptable for keysmashing than others.
QWERTY
Keysmashes typed on QWERTY keyboards are not as randomized as the action of keysmashing tends to imply. QWERTY keysmashes consistently |
https://en.wikipedia.org/wiki/NAIL-MS | NAIL-MS (short for nucleic acid isotope labeling coupled mass spectrometry) is a technique based on mass spectrometry used for the investigation of nucleic acids and its modifications. It enables a variety of experiment designs to study the underlying mechanism of RNA biology in vivo. For example, the dynamic behaviour of nucleic acids in living cells, especially of RNA modifications, can be followed in more detail.
Theory
NAIL-MS is used to study RNA modification mechanisms. Therefore, cells in culture are first fed with stable isotope labeled nutrients and the cells incorporate these into their biomolecules. After purification of the nucleic acids, most often RNA, analysis is done by mass spectrometry. Mass spectrometry is an analytical technique that measures the mass-to-charge ratio of ions. Pairs of chemically identical nucleosides of different stable-isotope composition can be differentiated in a mass spectrometer due to their mass difference. Unlabeled nucleosides can therefore be distinguished from their stable isotope labeled isotopologues. For most NAIL-MS approaches it is crucial that the labeled nucleosides are more than 2 Da heavier than the unlabeled ones. This is because 1.1% of naturally occurring carbon atoms are 13C isotopes. In the case of nucleosides this leads to a mass increase of 1 Da in ~10% of the nucleosides. This signal would disturb the final evaluation of the measurement.
NAIL-MS can be used to investigate RNA modification dynamics by changing the labeled nutrients of the corresponding growth medium during the experiment. Furthermore, cell populations can be compared directly with each other without effects of purification bias. Furthermore, it can be used for the production of biosynthetic isotopologues of most nucleosides which are needed for quantification by mass spectrometry and even for the discovery of yet unknown RNA modifications.
General procedure
In general, cells are cultivated in unlabeled or stable (non-radioactive) |
https://en.wikipedia.org/wiki/Infeld%E2%80%93Van%20der%20Waerden%20symbols | The Infeld–Van der Waerden symbols, sometimes called simply Van der Waerden symbols, are an invariant symbol associated to the Lorentz group used in quantum field theory. They are named after Leopold Infeld and Bartel Leendert van der Waerden.
The Infeld–Van der Waerden symbols are index notation for Clifford multiplication of covectors on left handed spinors giving a right-handed spinors or vice versa, i.e. they are off diagonal blocks of gamma matrices. The symbols are typically denoted in Van der Waerden notation as
and so have one Lorentz index (m), one left-handed (undotted Greek), and one right-handed (dotted Greek) Weyl spinor index. They satisfy
They need not be constant, however, and can therefore be formulated on curved space time.
Background
The existence of this invariant symbol follows from a result in the representation theory of the Lorentz group or more properly its Lie algebra. Labeling irreducible representations by , the spinor and its complex conjugate representations are the left and right fundamental representations
and
while the tangent vectors live in the vector representation
The tensor product of one left and right fundamental representation is the vector representation,. A dual statement is that the tensor product of the vector, left, and right fundamental representations contains the trivial representation which is in fact generated by the construction of the Lie algebra representations through the Clifford algebra (see below)
Infeld–Van der Waerden symbols and representations of the Clifford algebra
Consider the space of positive Weyl spinors of a Lorentzian vector space with dual .
Then the negative Weyl spinors can be identified with the vector space of complex conjugate dual spinors.
The Weyl spinors implement "two halves of a Clifford algebra representation" i.e. they come with a multiplication by covectors implemented as maps
and
which we will call Infeld–Van der Waerden maps. Note that in a natural way we can a |
https://en.wikipedia.org/wiki/Spendor | Spendor is a British loudspeaker manufacturing company founded in 1969 by audio engineer Spencer Hughes (1924–1983) and his wife Dorothy. It is located in East Sussex. The name was derived from the first names of both.
Research in the 1960s
Spencer Hughes worked in an investigation team of the BBC research department in the 1960s. Though journeying into Television, this was a time period when the BBC's licence budget meant the main transmission output was still radio, the imperative behind that of a BBC licensed loudspeaker was that (within the physical confines of a small bookshelf speaker) the principle objective of the loudspeaker was to reproduce an output audio signal with an acoustic fidelity to an original radio presenter's voice; principally within the entire spoken vocal range. To this end the resultant, and historically important BBC LS35A loudspeaker hit the retail market, the optional license meant any manufacture could procure a license to produce the LS35A design only if they were able to build a speaker which matched the same high fidelity standard the BBC had worked to achieve. The goal of the BBC R&D team had been reached with the original LS35A standard was now available to consumers who had the means to buy an amplification and loudspeaker system guaranteed to bring in to their homes the exact same sonic signature BBC sound engineers heard while recording and during replay. An alternative, the unwieldily, but sonically superior Quad Acoustics Electrostatic Loudspeaker ("ELS") were simply too large and pricey for most audiophiles.
One resulting offshoot of the research was a membrane made from a polystyrene ("Bextrene") for mid-range speakers or woofers.
History
Start
In the first days Dorothy assisted with coil winding expertise, later she took over the general management.
The first product was the BC1, which Spencer designed while still working for the BBC. Several other designs followed, the BC2, BC3, SA1, SP1 and other. Spendor also made |
https://en.wikipedia.org/wiki/Signed%20set | In mathematics, a signed set is a set of elements together with an assignment of a sign (positive or negative) to each element of the set.
Representation
Signed sets may be represented mathematically as an ordered pair of disjoint sets, one set for their positive elements and another for their negative elements. Alternatively, they may be represented as a Boolean function, a function whose domain is the underlying unsigned set (possibly specified explicitly as a separate part of the representation) and whose range is a two-element set representing the signs.
Signed sets may also be called -graded sets.
Application
Signed sets are fundamental to the definition of oriented matroids.
They may also be used to define the faces of a hypercube. If the hypercube consists of all points in Euclidean space of a given dimension whose Cartesian coordinates are in the interval , then a signed subset of the coordinate axes can be used to specify the points whose coordinates within the subset are or (according to the sign in the signed subset) and whose other coordinates may be anywhere in the interval . This subset of points forms a face, whose codimension is the cardinality of the signed subset.
Combinatorics
Enumeration
The number of signed subsets of a given finite set of elements is , a power of three, because there are three choices for each element: it may be absent from the subset, present with positive sign, or present with negative sign. For the same reason, the number of signed subsets of cardinality is
and summing these gives an instance of the binomial theorem,
Intersecting families
An analogue of the Erdős–Ko–Rado theorem on intersecting families of sets holds also for signed sets. The intersection of two signed sets is defined to be the signed set of elements that belong to both and have the same sign in both. According to this theorem, for any a collection of signed subsets of an -element set, all having cardinality and all pairs having a non-empty inte |
https://en.wikipedia.org/wiki/Game%20analytics | Game analytics is the form of behavioral analytics that deals with video games. Game analytics involve using quantitative measures, metrics, and tools that can be used to track events that occur over the course of a game, with the goal of capturing such data for statistical analysis. A simple example would be programming a video game to record the number of time each players die in each level and send the data back to the developer, so that developer will know whether some of the levels may be too difficult (i.e., with an excessively high number of player dying) and thus need redesign. The aim of using a game analytics platform is to generate insights to inform developers with regards to player behaviors and business decisions.
See also
Behavioral analytics
References
Applied data mining |
https://en.wikipedia.org/wiki/Berge%20equilibrium | The Berge equilibrium is a game theory solution concept named after the mathematician Claude Berge. It is similar to the standard Nash equilibrium, except that it aims to capture a type of altruism rather than purely non-cooperative play. Whereas a Nash equilibrium is a situation in which each player of a strategic game ensures that they personally will receive the highest payoff given other players' strategies, in a Berge equilibrium every player ensures that all other players will receive the highest payoff possible. Although Berge introduced the intuition for this equilibrium notion in 1957, it was only formally defined by Vladislav Iosifovich Zhukovskii in 1985, and it was not in widespread use until half a century after Berge originally developed it.
History
The Berge equilibrium was first introduced in Claude Berge's 1957 book Théorie générale des jeux à n personnes. Moussa Larbani and Vladislav Iosifovich Zhukovskii write that the ideas in this book were not widely used in Russia partly due to a harsh review that it received shortly after its translation into Russian in 1961, and they were not used in the English speaking world because the book had only received French and Russian printings. These explanations are echoed by other authors, with Pierre Courtois et al. adding that the impact of the book was likely dampened by its lack of economic examples, as well as by its reliance on tools from graph theory that would have been less familiar to economists of the time.
Berge introduced his original equilibrium notion only in intuitive terms, and the first formal definition of the Berge equilibrium was published by Vladislav Iosifovich Zhukovskii in 1985. The topic of Berge equilibria was then studied in detail by Konstantin Semenovich Vaisman in his 1995 PhD dissertation, and Larbani and Zhukovskii document that the tool became more widely used in the mid-2000s as economists became interested in increasingly complex systems in which players might be more incl |
https://en.wikipedia.org/wiki/Datera | Datera was a global enterprise software company headquartered in Santa Clara, California that developed an enterprise software-defined storage platform. Datera was acquired by VMware in April 2021.
The Datera Data Services Platform is the company's commercial product aimed at hyperscale storage environments and cloud service providers who want to deploy a hybrid cloud, autonomous and dynamic data infrastructure. Datera software deploys on industry-standard servers from Dell EMC, Fujitsu, Hewlett Packard Enterprise, Intel, Lenovo, Supermicro, and QUANTA to store blocks and objects in on-premises data centers, and private cloud and hybrid cloud environments.
History
Datera was co-founded in 2013 by contributors to open-source LIO_(SCSI_target) storage, Marc Fleischmann, Nicholas Bellinger and Claudio Fleiner. In 2016, Datera emerged from stealth and raised $40 million in funding from Khosla Ventures, Samsung Ventures, Andy Bechtolsheim, and Pradeep Sindhu.
Datera partnered with open source private cloud platform, vScaler in 2017 to deliver scalable private clouds for a range of workloads from high-performance databases to archival storage.
Guy Churchward, the former CEO at DataTorrent and Divisional President of Core Technologies at Dell EMC, joined the Datera board of directors in 2018 and was appointed CEO in December of that year. Flavio Santoni, the former EVP at LSI Corporation and former CEO of Syncsort, was appointed Chief Revenue Officer in January 2017. Narasimha Valiveti, former VP of software engineering at Dell EMC was appointed Chief Product Officer in May 2018.
In January 2019, Datera announced a go-to-market partnership with Hewlett Packard Enterprise as part of the HPE Complete program to allow businesses to procure integrated solutions on a single HPE purchase order. Datera reported 500 percent business growth in the first half of 2019 that was attributed to the HPE partnership.
In October 2019, Datera announced the HPE Datera Cloud Kit in par |
https://en.wikipedia.org/wiki/Guanine%20tetrad | In molecular biology, a guanine tetrad (also known as a G-tetrad or G-quartet) is a structure composed of four guanine bases in a square planar array. They most prominently contribute to the structure of G-quadruplexes, where their hydrogen bonding stabilizes the structure. Usually, there are at least two guanine tetrads in a G-quadruplex, and they often feature Hoogsteen-style hydrogen bonding.
Guanine tetrads are formed by sequences rich in guanine, such as GGGGC. They may also play a role in the dimerization of non-endogenous RNAs to facilitate the replication of some viruses. Guanine tetrads dimerize through their 5' ends since it is more energetically favorable.
They can be stabilized by central cations, such as lithium, sodium, potassium, rubidium, or cesium. However, they still form a variety of different structures. Guanine tetrads are not always stable, but the sugar-phosphate backbone of DNA can assist in stability of the guanine tetrads themselves. Guanine tetrads are more stable when stacked, as intermolecular forces between each layers help stabilize them.
Guanine tetrads can also influence recombination, replication, and transcription. For instance, guanine tetrads are found in the promoter region of the Myc family of oncogenes. They also function in immunoglobulin class switching and may play a role in the genome of HIV. Guanine tetrads appear frequently in the telomeric regions of DNA.
See also
G-quadruplex
Hoogsteen base pair
Heterochromatin
Regulation of gene expression
Guanine
Telomere
References
External links
QGRS Mapper
QuadBase2
Molecular biology
Molecular genetics
Cell biology
DNA
G-quadruplex |
https://en.wikipedia.org/wiki/Management%20system%20%28open%20source%29 | Management System (Open Source) is a socio-technical system that leverages the cumulative knowledge of management practitioners and evidenced based research from the past 130 years. The system was developed by DoD components in partnership with industry experts and academic researchers and builds off of the US Department of Wars version 1.0 open source management system - Training Within Industry.
The system integrates the four organizational components of Product, Structure, Process and People. In addition, the system is based on the 4 capabilities of rapid problem solving underlying the Toyota Production System:
Design and Operate Work to See Problems (See Problems).
Solve Problems Close in Person, Place & Time (Solve Problems).
Capture and Share Knowledge from solving those problems (Share Knowledge).
Managers Coach their Team in capabilities 1-3 (Managers Coach).
Derived from the original research of Steven J. Spear (Harvard Business School, Massachusetts Institute for Technology), the system balances the two dimensions of high performing organizations: integrate the whole (product, structure, process & people); and increase the rate of problem solving to manage the whole (4 capabilities outlined above).
Fundamentally, the system sets the standards of management by outlining a doctrine of rules, tactics, techniques, procedures & terms. The standards are intended to motivate change by creating a tension between the organization's "current condition" and the "ideal condition" (i.e. True North).
The objective of the system is to deliver more value, in less time, at less cost relative to the competition (better, faster, cheaper). For the DoD, competition is defined by the threats posed by current and potential adversaries.
Open Source (Many Names)
Over the last 25 years, the US Department of Defense has leveraged evidence based research in their attempt to improve the management capability of the Department. DoD's need for change comes from an increased |
https://en.wikipedia.org/wiki/Government%20Identity%20System%20%28United%20Kingdom%29 | The Government Identity System is maintained by His Majesty's Government to present unified branding format for the logos of government ministries, agencies and arms length bodies. The format was introduced in 2012 alongside a revamp of gov.uk to provide a clearer brand for all government work.
The consistent element of the Government identity is the Royal Coat of Arms, with the text name of the organisation below it, and a vertical line of colour to the left.
Exemptions to the use of the Royal Coat of Arms may be permitted when an organisation has its own arms, insignia, or symbol. These include:
HM Coast Guard
HM Revenue & Customs
Home Office and associated agencies
Department for International Trade
Government Communications Headquarters
Ministry of Defence and associated agencies
Scotland Office
Secret Intelligence Service
Security Service
UK Hydrographic Office
UK Atomic Energy Authority
Wales Office
References
Identity management
Identity management systems |
https://en.wikipedia.org/wiki/Cummins%20Quantum%20Series | Cummins Quantum Series is a family of internal combustion engines, developed and manufactured by American Cummins for various heavy-duty use cases. The Quantum series comes with an electronic controlled module. It is used in heavy duty machines and in railway machines.
Current types
The lineup consists of adaptations of F, B, L, X series and Quantum-only K series. There are also G12 and T30 engines in the lineup.
Diesel engines
Vast majority of Quantum series engines are Diesel engines. Those are compared in the table below:
Gas engines
Natural gas engines also exist.
Notes
References
Cummins diesel engines |
https://en.wikipedia.org/wiki/ISO/IEC%2027017 | ISO/IEC 27017 is a security standard developed for cloud service providers and users to make a safer cloud-based environment and reduce the risk of security problems. It was published by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) under the joint ISO and IEC subcommittee, ISO/IEC JTC 1/SC 27. It is part of the ISO/IEC 27000 family of standards, standards which provides best practice recommendations on information security management. This standard was built from ISO/IEC 27002, suggesting additional security controls for the cloud which were not completely defined in ISO/IEC 27002.
This International Standard provides guidelines supporting the implementation of information security controls for cloud service customers, who implements the controls, and cloud service providers to support the implementations of those controls. The selection of appropriate information security controls and the application of the implementation guidance provided, will depend on a risk assessment and any legal, contractual, regulatory or other cloud-sector specific information security requirements.
What does the standard provide?
ISO/IEC 27017 provides guidelines for information security controls applicable to the use of cloud services by providing an additional implementation guidance for 37 controls specified in ISO/IEC 27002 and 7 additional controls related to cloud services which address the following:
Who is responsible for what between the cloud service provider and the cloud customer.
The removal or return of assets at the end of a contract.
Protection and separation of the customer's virtual environment.
Virtual machine configuration.
Administrative operations and procedures associated with the cloud environment.
Cloud customer monitoring of activity.
Virtual and cloud network environment alignment.
Structure of the standard
The official title of the standard is "Information technology — Security tech |
https://en.wikipedia.org/wiki/Zoom%20%28software%29 | Zoom (stylized as zoom), also called Zoom Meetings, is a proprietary videotelephony software program developed by Zoom Video Communications. The free plan allows up to 100 concurrent participants, with a 40-minute time restriction. Users have the option to upgrade by subscribing to a paid plan, the highest of which supports up to 1,000 concurrent participants for meetings lasting up to 30 hours.
History
A beta version of Zoom that could host conferences with only up to 15 video participants was launched on August 21, 2012. On January 25, 2013, version 1.0 of the program was released with an increase in the number of participants per conference to 25. By the end of its first month, Zoom had 400,000 users and rose to over one million users by May 2013. After the start of the COVID-19 pandemic, by February 2020, Zoom had gained 2.22 million users in 2020 – more users than it amassed in the entirety of 2019. In March 2020, the Zoom app was downloaded 2.13 million times.
During the COVID-19 pandemic, there was a major increase in the use of Zoom for remote work, distance education, and online social relations. Zoom was one of the most downloaded mobile apps worldwide in 2020 with over 500 million downloads.
In April 2020, Zoom had more than 300 million daily meeting participants, clarified to mean the number of times someone joined a meeting, which could happen several times per day.
Features
Zoom One has six tiers: Basic, Pro, Business, Business Plus, Enterprise, and Enterprise Plus. Zoom is compatible with Windows, macOS, iOS, Android, ChromeOS, and Linux. It is noted for its simple interface and usability, regardless of technological expertise. Features include one-on-one meetings, group video conferences, screen sharing, plugins, browser extensions, and the ability to record meetings and have them automatically transcribed. On some computers and operating systems, users are able to select a virtual background, which can be downloaded from different sites, to us |
https://en.wikipedia.org/wiki/Pl%40ntNet | Pl@ntNet is a citizen science project for automatic plant identification through photographs and based on machine learning.
History
This project launched in 2009 has been developed by scientists (computer engineers and botanists) from a consortium gathering French research institutes (Institut de recherche pour le développement (IRD), Centre de coopération internationale en recherche agronomique pour le développement (CIRAD), Institut national de la recherche agronomique (INRA), Institut national de recherche en informatique et en automatique (INRIA) and the network Tela Botanica, with the support of Agropolis Fondation
).
Platforms
An app for smartphones (and a web version) was launched in 2013, which allows to identify thousands of plant species from photographs taken by the user. It is available in several languages.
As of 2019 it had been downloaded over 10 million times, in more than 180 countries worldwide.
Projects
In 2019, Pl@ntNet has 22 projects:
References
Botany
Citizen science
Biology websites
Internet properties established in 2009 |
https://en.wikipedia.org/wiki/Together%20at%20Home | One World: Together at Home (also known as Together at Home) is a benefit concert that was organized by Global Citizen of New York City and curated by singer Lady Gaga in support of the World Health Organization. The special was intended to promote the practice of social distancing while staying together during the COVID-19 pandemic.
On April 18, 2020, a six-hour pre-show was streamed online immediately prior to the television global broadcast. The online portion of the event was hosted through YouTube by actress and presenter Jameela Jamil (first hour), actor Matthew McConaughey (second hour), actress Danai Gurira (third hour), singer Becky G (fourth hour), actress Laverne Cox (fifth hour) and actor Don Cheadle (sixth hour). It featured appearances from numerous celebrities.
Participants of concert series
Alex Gaskarth
Alissa White-Gluz
Amy Lee
Amy Shark
Anne-Marie
Anthony Hamilton
Camila Cabello
Carla Morrison
Caroline Hjelt
Celeste
Charlie Puth
Chris Martin
Common
Dermot Kennedy
Elize Ryd
G Flip
Gloria Gaynor
Guy Sebastian
Ha*Ash
H.E.R.
Jack Johnson
James Bay
Jason Mraz
John Legend
Jon Batiste
Joshua Bassett
Julianne Hough
Juanes
Koffee
Liam Payne
Lindsey Stirling
Meghan Trainor
Niall Horan
Nikki Yanofsky
Noah Cyrus
Nomfusi
OneRepublic
Rod and Ruby Stewart
Rufus Wainwright
Simone Simons
Tarja Turunen
Vance Joy
Wesley Schultz
Within Temptation
Years & Years
Ziggy Marley
Television special
The television special, titled One World: Together at Home, was curated in collaboration between Global Citizen and singer-songwriter Lady Gaga, which benefited the World Health Organization's COVID-19 Solidarity Response Fund. Jimmy Fallon, Jimmy Kimmel, and Stephen Colbert hosted the show, which was a syndicated broadcast that aired on April 18, 2020. The special was also simulcast on select U.S. cable television networks, streaming platforms, and international broadcast networks. In the UK, the show was hosted by Clara Amfo, De |
https://en.wikipedia.org/wiki/Equivalents%20of%20the%20Axiom%20of%20Choice | Equivalents of the Axiom of Choice is a book in mathematics, collecting statements in mathematics that are true if and only if the axiom of choice holds. It was written by Herman Rubin and Jean E. Rubin, and published in 1963 by North-Holland as volume 34 of their Studies in Logic and the Foundations of Mathematics series. An updated edition, Equivalents of the Axiom of Choice, II, was published as volume 116 of the same series in 1985.
Topics
At the time of the book's original publication, it was unknown whether the axiom of choice followed from the other axioms of Zermelo–Fraenkel set theory (ZF), or was independent of them, although it was known to be consistent with them from the work of Kurt Gödel. This book codified the project of classifying theorems of mathematics according to whether the axiom of choice was necessary in their proofs, or whether they could be proven without it. At approximately the same time as the book's publication, Paul Cohen proved that the negation of the axiom of choice is also consistent, implying that the axiom of choice, and all of its equivalent statements in this book, are indeed independent of ZF.
The first edition of the book includes over 150 statements in mathematics that are equivalent to the axiom of choice, including some that are novel to the book. This edition is divided into two parts, the first involving notions expressed using sets and the second involving classes instead of sets. Within the first part, the topics are grouped into statements related to the well-ordering principle, the axiom of choice itself, trichotomy (the ability to compare cardinal numbers), and Zorn's lemma and related maximality principles. This section also includes three more chapters, on statements in abstract algebra, statements for cardinal numbers, and a final collection of miscellaneous statements. The second section has four chapters, on topics parallel to four of the first section's chapters.
The book includes the history of each state |
https://en.wikipedia.org/wiki/Microsoft%20MACRO-80 | Microsoft MACRO-80 (often shortened to M80) is a relocatable macro assembler for Intel 8080 and Zilog Z80 microcomputer systems.
The complete MACRO-80 package includes the MACRO-80 Assembler, the LINK-80 Linking Loader, and the CREF-80 Cross Reference Facility. The LIB-80 Library Manager is included in CP/M versions only.
The list price at the time was $200.
Overview
A MACRO-80 source program consists of a series of statements. Each statement must follow a predefined format. Source lines up to 132 characters in length are supported. M80 accepts source files almost identical to files for Intel-compatible assemblers. It also supports several switches in the command string. Some can be used to control the format of the source file. A switch can be set to allow support for Z80 mnemonics.
MACRO-80 runs on Digital Research CP/M, Intel ISIS-II, Tandy TRSDOS, Tektronix TEKDOS, and Microsoft MSX-DOS.
See also
Microsoft Macro Assembler
Assembly language
High-level assembler
Comparison of assemblers
References
External links
CP/M-80 Information and Download Page
Assemblers
MACRO-80
MSX-DOS |
https://en.wikipedia.org/wiki/Hyperbolastic%20functions | The hyperbolastic functions, also known as hyperbolastic growth models, are mathematical functions that are used in medical statistical modeling. These models were originally developed to capture the growth dynamics of multicellular tumor spheres, and were introduced in 2005 by Mohammad Tabatabai, David Williams, and Zoran Bursac. The precision of hyperbolastic functions in modeling real world problems is somewhat due to their flexibility in their point of inflection. These functions can be used in a wide variety of modeling problems such as tumor growth, stem cell proliferation, pharma kinetics, cancer growth, sigmoid activation function in neural networks, and epidemiological disease progression or regression.
The hyperbolastic functions can model both growth and decay curves until it reaches carrying capacity. Due to their flexibility,
these models have diverse applications in the medical field, with the ability to capture disease progression with an intervening
treatment. As the figures indicate, hyperbolastic functions can fit a sigmoidal curve indicating that the slowest rate occurs at
the early and late stages. In addition to the presenting sigmoidal shapes, it can also accommodate biphasic situations where medical
interventions slow or reverse disease progression; but, when the effect of the treatment vanishes, the disease will begin the
second phase of its progression until it reaches its horizontal asymptote.
One of the main characteristics these functions have is that they cannot only fit sigmoidal shapes, but can also model biphasic growth patterns that other classical sigmoidal curves cannot adequately model. This distinguishing feature has advantageous applications in various fields including medicine, biology, economics, engineering, agronomy, and computer aided system theory.
Function H1
The hyperbolastic rate equation of type I, denoted H1, is given by
where is any real number and
is the population size at . The parameter represents c |
https://en.wikipedia.org/wiki/Regulation%20of%20algorithms | Regulation of algorithms, or algorithmic regulation, is the creation of laws, rules and public sector policies for promotion and regulation of algorithms, particularly in artificial intelligence and machine learning. For the subset of AI algorithms, the term regulation of artificial intelligence is used. The regulatory and policy landscape for artificial intelligence (AI) is an emerging issue in jurisdictions globally, including in the European Union. Regulation of AI is considered necessary to both encourage AI and manage associated risks, but challenging. Another emerging topic is the regulation of blockchain algorithms (Use of the smart contracts must be regulated) and is mentioned along with regulation of AI algorithms. Many countries have enacted regulations of high frequency trades, which is shifting due to technological progress into the realm of AI algorithms.
The motivation for regulation of algorithms is the apprehension of losing control over the algorithms, whose impact on human life increases. Multiple countries have already introduced regulations in case of automated credit score calculation—right to explanation is mandatory for those algorithms. For example, The IEEE has begun developing a new standard to explicitly address ethical issues and the values of potential future users. Bias, transparency, and ethics concerns have emerged with respect to the use of algorithms in diverse domains ranging from criminal justice to healthcare—many fear that artificial intelligence could replicate existing social inequalities along race, class, gender, and sexuality lines.
Regulation of artificial intelligence
Public discussion
In 2016, Joy Buolamwini founded Algorithmic Justice League after a personal experience with biased facial detection software in order to raise awareness of the social implications of artificial intelligence through art and research.
In 2017 Elon Musk advocated regulation of algorithms in the context of the existential risk from artifi |
https://en.wikipedia.org/wiki/Quantum%20Computing%3A%20A%20Gentle%20Introduction | Quantum Computing: A Gentle Introduction is a textbook on quantum computing. It was written by Eleanor Rieffel and Wolfgang Polak, and published in 2011 by the MIT Press.
Topics
Although the book approaches quantum computing through the model of quantum circuits, it is focused more on quantum algorithms than on the construction of quantum computers. It has 13 chapters, divided into three parts: "Quantum building blocks" (chapters 1–6), "Quantum algorithms" (chapters 7–9), and "Entangled subsystems and robust quantum computation" (chapters 10–13).
After an introductory chapter overviewing related topics including quantum cryptography, quantum information theory, and quantum game theory, chapter 2 introduces quantum mechanics and quantum superposition using polarized light as an example, also discussing qubits, the Bloch sphere representation of the state of a qubit, and quantum key distribution. Chapter 3 introduces direct sums, tensor products, and quantum entanglement, and chapter 4 includes the EPR paradox, Bell's theorem on the impossibility of local hidden variable theories, as quantified by Bell's inequality. Chapter 5 discusses unitary operators, quantum logic gates, quantum circuits, and functional completeness for systems of quantum gates. Chapter 6, the final chapter of the building block section, discusses (classical) reversible computing, and the conversion of arbitrary computations to reversible computations, a necessary step to performing them on quantum devices.
In the section of the book on quantum algorithms, chapter 7 includes material on quantum complexity theory and the Deutch algorithm, Deutsch–Jozsa algorithm, Bernstein–Vazirani algorithm, and Simon's algorithm, algorithms devised to prove separations in quantum complexity by solving certain artificial problems faster than could be done classically. It also covers the quantum Fourier transform. Chapter 8 covers Shor's algorithm for integer factorization, and introduces the hidden subgroup pro |
https://en.wikipedia.org/wiki/Davenport%E2%80%93Schinzel%20Sequences%20and%20Their%20Geometric%20Applications | Davenport–Schinzel Sequences and Their Geometric Applications is a book in discrete geometry. It was written by Micha Sharir and Pankaj K. Agarwal, and published by Cambridge University Press in 1995, with a paperback reprint in 2010.
Topics
Davenport–Schinzel sequences are named after Harold Davenport and Andrzej Schinzel, who applied them to certain problems in the theory of differential equations. They are finite sequences of symbols from a given alphabet, constrained by forbidding pairs of symbols from appearing in alternation more than a given number of times (regardless of what other symbols might separate them). In a Davenport–Schinzel sequence of order , the longest allowed alternations have length . For instance, a Davenport–Schinzel sequence of order three could have two symbols and that appear either in the order or , but longer alternations like would be forbidden. The length of such a sequence, for a given choice of , can be only slightly longer than its number of distinct symbols. This phenomenon has been used to prove corresponding near-linear bounds on various problems in discrete geometry, for instance showing that the unbounded face of an arrangement of line segments can have complexity that is only slightly superlinear. The book is about this family of results, both on bounding the lengths of Davenport–Schinzel sequences and on their applications to discrete geometry.
The first three chapters of the book provide bounds on the lengths of Davenport–Schinzel sequences whose superlinearity is described in terms of the inverse Ackermann function . For instance, the length of a Davenport–Schinzel sequence of order three, with symbols, can be at most , as the second chapter shows; the third concerns higher orders. The fourth chapter applies this theory to line segments,
and includes a proof that the bounds proven using these tools are tight: there exist systems of line segments whose arrangement complexity matches the bounds on Davenport–Schinzel |
https://en.wikipedia.org/wiki/Distributed%20data%20processing | Distributed data processing (DDP) was the term that IBM used for the IBM 3790 (1975) and its successor, the IBM 8100 (1979). Datamation described the 3790 in March 1979 as "less than successful."
Distributed data processing was used by IBM to refer to two environments:
IMS DB/DC
CICS/DL/I
Each pair included a Telecommunications Monitor and a Database system. The layering involved a message, containing information to form a transaction, which was then processed by an application program. Development tools such as program validation services were released by IBM to facilitate expansion.
Use of "a number of small computers linked to a central computer" permitted local and central processing, each optimized at what it could best do. Terminals, including those described as intelligent, typically were attached locally, to a "satellite processor." Central systems, sometimes multi-processors, grew to handle the load. Some of this extra capacity, of necessity, is used to enhance data security. Years before open systems made its presence felt, the goal of some hardware suppliers was "to replace the big, central mainframe computer with an array of smaller computers that are tied together."
Lower case distributed data processing
Hadoop adds another term to the mix: File System. Tools added for this use of distributed data processing include new programming languages.
TSI/DPF Flexicom
In 1976 Turnkey Systems Inc (TSI)/DPF Inc. introduced a hardware/software telecommunications front-end to off-load some processing that handled distributed data processing. Named Flexicom, The CPU was IBM-manufactured, and it ran (mainframe) DOS Rel. 26, with Flexicom's additions. Of four models available, the smallest had the CPU of
a 360/30.
See also
HPCC
References
History of computing hardware
Computer-related introductions in 1975 |
https://en.wikipedia.org/wiki/List%20of%20gene%20therapies | This article contains a list of commercially available gene therapies.
Gene therapies
Alipogene tiparvovec (Glybera): AAV-based treatment for lipoprotein lipase deficiency (no longer commercially available)
Axicabtagene ciloleucel (Yescarta): treatment for large B-cell lymphoma
Beremagene geperpavec (Vyjuvek): treatment of wounds.
Betibeglogene autotemcel (Zynteglo): treatment for beta thalassemia
Brexucabtagene autoleucel (Tecartus): treatment for mantle cell lymphoma and acute lymphoblastic leukemia
Cambiogenplasmid (Neovasculgen): treatment for vascular endothelial growth factor peripheral artery disease
Ciltacabtagene autoleucel (Carvykti): treatment for multiple myeloma
Delandistrogene moxeparvovec (Elevidys): treatment for Duchenne muscular dystrophy
Elivaldogene autotemcel (Skysona): treatment for cerebral adrenoleukodystrophy
Etranacogene dezaparvovec (Hemgenix): AAV-based treatment for hemophilia B
Gendicine: treatment for head and neck squamous cell carcinoma
Idecabtagene vicleucel (Abecma): treatment for multiple myeloma
Nadofaragene firadenovec (Adstiladrin): treatment for bladder cancer
Onasemnogene abeparvovec (Zolgensma): AAV-based treatment for spinal muscular atrophy
Strimvelis: treatment for adenosine deaminase deficiency (ADA-SCID)
Talimogene laherparepvec (Imlygic): treatment for melanoma in patients who have recurring skin lesions
Tisagenlecleucel (Kymriah): treatment for B cell lymphoblastic leukemia
Valoctocogene roxaparvovec (Roctavian): treatment for hemophilia A
Voretigene neparvovec (Luxturna): AAV-based treatment for Leber congenital amaurosis
See also
FDA-approved CAR T cell therapies
References
External links
Applied genetics
Bioethics
Biotechnology
Medical genetics
Gene therapies
Gene delivery
Emerging technologies
Genetic engineering |
https://en.wikipedia.org/wiki/Impact%20of%20the%20COVID-19%20pandemic%20on%20the%20video%20game%20industry | The video game industry has been substantially impacted by the COVID-19 pandemic in various ways, most often due to concerns over travel to and from China or elsewhere, and delays in the manufacturing processes within China.
Overview
In contrast to many other economic sectors that are drastically affected by the pandemic, the video game industry has been more resilient. Most video game developers, publishers, and operators have been able to maintain operations with employees remote working to sustain game development and digital releases, though some productivity issues arose. With many people globally at home and unable to work, online gaming has observed record numbers of players during the pandemic as a popular activity to counter physical distancing for society, a practice recommended by the World Health Organization that helped boost revenues for many companies in the gaming industry.
There have still been negative impacts on the industry, notably with major trade events like E3 2020 cancelled or postponed which may have impacted relationships between the smaller developers and publishers. This has particularly impacted indie developers who typically use these events for face-to-face meetings with potential partners to gain funding and publishing support, and caused them to have to delay or cancel projects. Many esport leagues had to alter plans for their games, transitioning from live events to remote play or cancellation altogether. Portions of the sector that relied on physical products, such as retail stores and peripheral makers, as well as those dependent on in-person activities such as quality assurance through playtesting, ratings evaluation, and marketing, also struggled with global stay-at-home orders.
As the origin of the pandemic, China is expected to impact the supply chains for electronics, which may limit hardware availability once the pandemic begins to be resolved. However, it did not impact plans for Microsoft and Sony to release the Xbox S |
https://en.wikipedia.org/wiki/Marine%20viruses | Marine viruses are defined by their habitat as viruses that are found in marine environments, that is, in the saltwater of seas or oceans or the brackish water of coastal estuaries. Viruses are small infectious agents that can only replicate inside the living cells of a host organism, because they need the replication machinery of the host to do so. They can infect all types of life forms, from animals and plants to microorganisms, including bacteria and archaea.
When not inside a cell or in the process of infecting a cell, viruses exist in the form of independent particles called virions. A virion contains a genome (a long molecule that carries genetic information in the form of either DNA or RNA) surrounded by a capsid (a protein coat protecting the genetic material). The shapes of these virus particles range from simple helical and icosahedral forms for some virus species to more complex structures for others. Most virus species have virions that are too small to be seen with an optical microscope. The average virion is about one one-hundredth the linear size of the average bacterium.
A teaspoon of seawater typically contains about fifty million viruses. Most of these viruses are bacteriophages which infect and destroy marine bacteria and control the growth of phytoplankton at the base of the marine food web. Bacteriophages are harmless to plants and animals but are essential to the regulation of marine ecosystems. They supply key mechanisms for recycling ocean carbon and nutrients. In a process known as the viral shunt, organic molecules released from dead bacterial cells stimulate fresh bacterial and algal growth. In particular, the breaking down of bacteria by viruses (lysis) has been shown to enhance nitrogen cycling and stimulate phytoplankton growth. Viral activity also affects the biological pump, the process which sequesters carbon in the deep ocean. By increasing the amount of respiration in the oceans, viruses are indirectly responsible for reducing |
https://en.wikipedia.org/wiki/601st%20Engineer%20Grouping%20%28Argentina%29 | The 601 Engineer Grouping (Agr Ing 601) is an Argentine Army Engineer grouping. It is based at Campo de Mayo Army Garrison.
Structure
601 Engineer Grouping Headquarters. Campo de Mayo Army Garrison.
601 Engineer Battalion. Campo de Mayo Army Garrison.
601 CBRN and Emergency Support Company. San Nicolás de los Arroyos Barracks.
601 Facilities Maintenance Engineer Company. Villa Martelli Army Garrison.
601 Army Divers Engineer Company. Villa Martelli Army Garrison.
601 Transport Engineer Company. Campo de Mayo Army Garrison.
601 Water Engineer Company. Campo de Mayo Army Garrison.
Source
Humanitarian aids
In 2019, the Ministry of Defense supplied the 601 Engineer Grouping with heavy equipment, water treatment plants, pneumatic machines and tools, New Holland D-180C bulldozers, Komatsu WA-320 front loaders, Case 580-W backhoe loaders, GEFCO drills and Sany STC-800 cranes. Argentine Army's Engineer Branch personnel manufactured a water purification and bagging plant. It has a capacity of 6000 L by micro filtration or 3000 by reverse osmosis, and can pack 1200 sachets of water per hour.
In 2019, 601 Engineer Grouping elements deployed at Santa Cruz de la Sierra y Concepción, Bolivia, in order to provide logistical support to the fight against Amazon rainforest wildfires. The movement was carried out in coordination with units of the Navy of the Argentine Republic. Personnel and equipment of the Grouping with its Headquarters and Staff joined the mission, in addition to the 601st Water Engineer Company. Also operators of road machinery of the 601st Engineer Battalion. An approximate number of 200 troops was totaled.
References
Army units and formations of Argentina
San Miguel Partido
Engineering units and formations
Group sized units of armies (land forces) |
https://en.wikipedia.org/wiki/Floral%20isolation | Floral Isolation is a form of reproductive isolation found in angiosperms. Reproductive isolation is the process of species evolving mechanisms to prevent reproduction with other species. In plants, this is accomplished through the manipulation of the pollinator’s behavior (ethological isolation) or through morphological characteristics of flowers that favor intraspecific pollen transfer (morphological isolation). Preventing interbreeding prevents hybridization and gene flow between the species (introgression), and consequently protects genetic integrity of the species. Reproductive isolation occurs in many organisms, and floral isolation is one form present in plants. Floral isolation occurs prior to pollination, and is divided into two types of isolation: morphological isolation and ethological isolation. Floral isolation was championed by Verne Grant in the 1900s as an important mechanism of reproductive isolation in plants.
Morphological Isolation
Mechanical or morphological isolation is a form of floral isolation where the characteristics of the flower prevents reproduction between species. These morphological differences primarily affect the positioning of reproductive structures within flowers and control the placement of pollen on the pollinator’s body to promote transfer within the same species. For example, flowers of Salvia mellifera have anthers and stigmas which are positioned to contact the dorsal surface of the bumblebee abdomen while flowers of the co-occurring Salvia apiana place pollen on the bumblebee’s flanks.
Ethological Isolation
Ethological isolation is a form of floral isolation caused predominantly by the behavior of pollinators. Flowers can have morphological features which attract or reward specific types of pollinators. The relationship between floral signals and pollinators can promote floral constancy, where different pollinators preferentially visit one species over other others. The color or odor of flowers promot |
https://en.wikipedia.org/wiki/Mathematical%20Excursions | Mathematical Excursions: Side Trips along Paths Not Generally Traveled in Elementary Courses in Mathematics is a book on popular mathematics. It was written by Helen Abbot Merrill, published in 1933 by the Norwood Press, and reprinted (posthumously) by Dover Publications in 1957.
Topics
The book is devoted to mathematical puzzles and pastimes, gathered from Merrill's experience as a teacher. It has 15 chapters, most on arithmetic and number theory but with one on geometry.
Its topics include
squared triangular numbers and other sums of powers, Russian peasant multiplication, binary numbers, repeating decimals, magic squares, the irrationality of , mechanical linkages, linear Diophantine equations, the 15 puzzle, perfect numbers, and some unsolved problems in number theory.
Audience and reception
The book is written for a general audience, and is intended to spark the interest of high school students in mathematics.
In general, only high school levels of algebra and geometry are needed to appreciate the book and solve its problems.
It could be used as individual reading, or in mathematics clubs,
and also for mathematics teachers looking for examples and demonstrations for their classes.
Of the original edition, reviewer David Eugene Smith wrote "the book ought to be in the hands of all teachers and on the shelves of all high schools and colleges". By the time of the 1957 reprint, reviewer Samuel L. Greitzer complained about its obsolete notation, as well as its uneven level of exposition and non-uniform inclusion of solutions to problems, and reviewer Roland Sprague noted that its treatment of perfect numbers was out of date. Nevertheless, Greitzer suggested that it would be appropriate as "enrichment" for high-school students.
References
External links
Mathematical Excursions in the Hathitrust Digital Library: Norwood Press edition, ; Dover edition,
Popular mathematics books
1933 non-fiction books |
https://en.wikipedia.org/wiki/Taiwan%20Semiconductor%20Research%20Institute | The Taiwan Semiconductor Research Institute () (TSRI) is a research institute in Taiwan which was created in 2019 through the merger of the National Nano Device Laboratories and National Chip Implementation Center. It is part of the National Applied Research Laboratories under the Ministry of Science.
Overview
According to the China Times the Taiwan Semiconductor Research Institute is the "world’s only national science and technology research and development center which integrates integrated circuit design, chip offline manufacturing, and semiconductor component manufacturing process research."
History
The Taiwan Semiconductor Research Institute was created in 2019 through the merger of the National Nano Device Laboratories and National Chip Implementation Center under the National Applied Research Laboratories. TSRI was inaugurated on Jan. 30 2019 at Hsinchu Science Park.
National Chip Implementation Center
The Chip Implementation Center Establishment Project was initiated in 1992 with the National Chip Implementation Center (NCIC) being inaugurated in 1997. In 2003 it was incorporated into NARLabs. In 2007 the CIC had 106 employees with 66 being full-time researchers.
National Nano Device Laboratories
The National Nano Device Laboratories (NDL) was implemented under the National Submicron Device Laboratories Establishment Project in 1988. They began operating their first level-10 clean room in 1992. In 1993 they were renamed the National Millimicron Device Laboratories and in 2002 they were renamed the National Nano Device Laboratories. They were incorporated into NARLabs in 2003.
See also
Industrial Technology Research Institute
National Center for High-Performance Computing
References
2019 establishments in Taiwan
Research institutes in Taiwan
Computer science institutes |
https://en.wikipedia.org/wiki/Taiwan%20Typhoon%20and%20Flood%20Research%20Institute | The Taiwan Typhoon and Flood Research Institute (TTFRI) was a research institute which is part of the National Applied Research Laboratories of Taiwan. It was merged into the National Science and Technology Center for Disaster Reduction in 2018.
History
The Taiwan Typhoon and Flood Research Institute was inaugurated in 2011 in the city of Taichung. Lee Cheng-shang was the inaugural Director.
TTFRI is a coordinator of research into quantitative precipitation forecasting.
TTFRI has worked with the Central Weather Bureau to develop a radar assimilation system which has increased the accuracy of the six hour rainfall forecast by twenty percent.
In 2018 TTFRI began a project to improve the flood management of Cayo District in Belize in partnership with the Belizean Government which is one of Taiwan's few remaining official diplomatic allies.
Equipment
In 2015 TTFRI acquired a set of UAVs from Australia for use their typhoon research program. Early attempts to acquire UAVs in 2005 were scrapped due to stricter air traffic controls imposed as a result of global terrorism.
References
2011 establishments in Taiwan
Research institutes in Taiwan
Environmental research institutes
Stormwater management
Environmental engineering
2018 disestablishments in Taiwan |
https://en.wikipedia.org/wiki/Kac%27s%20lemma | In ergodic theory, Kac's lemma, demonstrated by mathematician Mark Kac in 1947, is a lemma stating that in a measure space the orbit of almost all the points contained in a set of such space, whose measure is , return to within an average time inversely proportional to .
The lemma extends what is stated by Poincaré recurrence theorem, in which it is shown that the points return in infinite times.
Application
In physics, a dynamical system evolving in time may be described in a phase space, that is by the evolution in time of some variables. If this variables are bounded, that is having a minimum and a maximum, for a theorem due to Liouville, a measure can be defined in the space, having a measure space where the lemma applies. As a consequence, given a configuration of the system (a point in the phase space) the average return period close to this configuration (in the neighbourhood of the point) is inversely proportional to the considered size of volume surrounding the configuration.
Normalizing the measure space to 1, it becomes a probability space and the measure of its set represents the probability of finding the system in the states represented by the points of that set. In this case the lemma implies that the smaller is the probability to be in a certain state (or close to it), the longer is the time of return near that state.
In formulas, if is the region close to the starting point and is the return period, its average value is:
Where is a characteristic time of the system in question.
Note that since the volume of , therefore , depends exponentially on the variables in the system (, with infinitesimal side, therefore less than 1, of the volume in dimensions), decreases very rapidly as the variables of the system increase and consequently the return period increases exponentially.
In practice, as the variables needed to describe the system increase, the return period increases rapidly.
References
Further reading
Ergodic theo |
https://en.wikipedia.org/wiki/Arginine%20finger | In molecular biology, an arginine finger is an amino acid residue of some enzymes. Arginine fingers are often found in the protein superfamily of AAA+ ATPases, GTPases, and dUTPases, where they assist in the catalysis of the gamma phosphate or gamma and beta phosphates from ATP or GTP, which creates a release of energy which can be used to perform cellular work. They are also found in GTPase-activating proteins (GAP). Thus, they are essential for many forms of life, and are highly conserved. Arginine fingers function through non-covalent interactions. They may also assist in dimerization, and while they are found in a wide variety of enzymes, they are not ubiquitous.
Role in catalytic mechanisms
Generally, the role of the arginine finger in catalysis is to function in transition state stabilization to allow water to perform a nucleophilic attack to cleave off a number of phosphate groups. However, there are exceptions, and arginine fingers can assist in other roles. Additionally, arginine fingers may be attached to different subunits or other proteins in a multiprotein complex. Arginine fingers sometimes interact with guanidinium during their role in catalysis.
dUTPases
Arginine fingers often work with other features in their assistance of catalysis. For example, in some trimeric dUTPases, such as those of M. tuberculosis, arginine fingers at the 64th and 140th residue can work with magnesium to cleave dUTP into dUMP and a pyrophosphate. The underlying mechanism of action for this is a nucleophilic attack; the positively charged magnesium ion () pulls on an oxygen of the beta and gamma phosphates to allow water to hydrolyze the bond between the beta and alpha phosphates. The arginine fingers help stabilize the transition state. Arginine fingers often interact with other motifs such as the Walker motifs and to perform catalysis more efficiently.
Ras GTPases
Arginine fingers are also present in Ras GTPases, where they help cleave GTP to turn Ras off. Ras is a GT |
https://en.wikipedia.org/wiki/Broad-spectrum%20antiviral%20drug | Broad-spectrum antivirals (BSAs) are a class of molecules or compounds, which inhibit the infection of multiple viruses from the same (intra-family BSAs) or different (inter-family BSAs) virus families. BSAs could be divided into experimental and investigational agents, and approved drugs. BSAs work by inhibiting viral proteins (such as polymerases and proteases) or by targeting host cell factors and processes exploited by different viruses during infection. As of 2021, there are 150 known BSAs in varying stages of development, effective against 78 human viruses. BSAs are potential candidates for treatment of emerging and re-emerging viruses, such as ebola, marburg, and SARS-CoV-2. Many BSAs show antiviral activity against other viruses than originally investigated (such as remdesivir and interferon alpha). Efforts in drug repurposing for SARS-CoV-2 is currently underway. A database of BSAs and viruses they inhibit could be found here (https://drugvirus.info/).
See also
Broad-spectrum antibiotic
Broad-spectrum therapeutic
References
Antiviral drugs
Viruses |
https://en.wikipedia.org/wiki/Tremont%20%28microarchitecture%29 | Tremont is a microarchitecture for low-power Atom, Celeron and Pentium Silver branded processors used in systems on a chip (SoCs) made by Intel. It is the successor to Goldmont Plus. Intel officially launched Elkhart Lake platform with 10 nm Tremont core on September 23, 2020. Intel officially launched Jasper Lake platform with 10 nm Tremont core on January 11, 2021.
Design
Tremont is the third generation out-of-order low-power Atom microarchitecture designed for the entry level desktop and notebook computers. Tremont is built on the 10 nm manufacturing process and supports up to 24 cores. It includes the Intel Gen11 graphics architecture from Ice Lake.
Tremont microarchitecture provides the following enhancements over Goldmont Plus:
Enhanced branch-prediction unit.
Increased capacity with improved path-based conditional and indirect prediction.
New committed return stack buffer.
Novel clustered 6-wide out-of-order front-end fetch and decode pipeline.
Banked ICache with dual 16B reads.
Two 3-wide decode clusters enabling up to 6 instructions per cycle.
Deeper back-end out-of-order windows.
32 KB data cache.
Larger load and store buffers.
Dual generic load and store execution pipes capable of 2 loads, 2 stores, or 1 load and 1 store per cycle.
Dedicated integer and vector integer/floating point store data ports.
New and improved cryptography.
New Galois-field instructions (GFNI).
Dual AES units.
Enhanced SHA-NI implementation.
Faster PCLMULQDQ.
Support for user level low-power and low-latency spin-loop instructions UMWAIT/UMONITOR and TPAUSE.
Technology
10 nm manufacturing process
SoC (System on a chip) architecture
3D tri-gate transistor
32 KB L1 data cache, up from 24 KB in Goldmont Plus
1.5–4.5 MB shared L2 cache per 4-core cluster, up from 4 MB in Goldmont Plus
4 MB shared L3 cache
Gen 11 GPU with DirectX 12, OpenGL 4.6, Vulkan 1.3, OpenGL ES 3.2 and OpenCL 3.0 support.
10 W thermal design power (TDP) desktop processors
6 W TDP m |
https://en.wikipedia.org/wiki/Brouwer%27s%20conjecture | In the mathematical field of spectral graph theory, Brouwer's conjecture is a conjecture by Andries Brouwer on upper bounds for the intermediate sums of the eigenvalues of the Laplacian of a graph in term of its number of edges.
The conjecture states that if G is a simple undirected graph and L(G) its Laplacian matrix, then its eigenvalues λn(L(G)) ≤ λn−1(L(G)) ≤ ... ≤ λ1(L(G)) satisfy
where m(G) is the number of edges of G.
State of the art
Brouwer has confirmed by computation that the conjecture is valid for all graphs with at most 10 vertices. It is also known that the conjecture is valid for any number of vertices if t = 1, 2, n − 1, and n.
For certain types of graphs, Brouwer's conjecture is known to be valid for all t and for any number of vertices. In particular, it is known that is valid for trees, and for unicyclic and bicyclic graphs. It was also proved that Brouwer’s conjecture holds for two large families of graphs; the first family of graphs is obtained from a clique by identifying each of its vertices to a vertex of an arbitrary c-cyclic graph, and the second family is composed of the graphs in which the removal of the edges of the maximal complete bipartite subgraph gives a graph each of whose non-trivial components is a c-cyclic graph.
For certain sequences of random graphs, Brouwer's conjecture holds true with probability tending to one as the number of vertices tends to infinity.
References
Algebraic graph theory
Matrices
Conjectures
Unsolved problems in graph theory |
https://en.wikipedia.org/wiki/ISO/IEC%2027018 | ISO/IEC 27018 is a security standard part of the ISO/IEC 27000 family of standards. It was the first international standard about the privacy in cloud computing services which was promoted by the industry. It was created in 2014 as an addendum to ISO/IEC 27001, the first international code of practice for cloud privacy. It helps cloud service providers who process personally identifiable information (PII) to assess risk and implement controls for protecting PII. It was published by the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) under the joint ISO and IEC subcommittee, ISO/IEC JTC 1/SC 27.
Standard Versions
That standard has two versions:
ISO/IEC 27018:2014
ISO/IEC 27018:2019
Structure of the standard
The official title of the standard is "Information technology — Security techniques — Code of practice for protection of personally identifiable information (PII) in public clouds acting as PII processors".
ISO/IEC 27018:2019 has eighteen sections, plus a long annex, which cover:
1. Scope
2. Normative References
3. Terms and definitions
4. Overview
5. Information security policies
6. Organization of information security
7. Human resource security
8. Asset management
9. Access control
10. Cryptography
11. Physical and environmental security
12. Operations security
13. Communications security
14. System acquisition, development and maintenance
15. Supplier relationships
16. Information security incident management
17. Information security aspects of business continuity management
18. Compliance
Objectives
The objective of this document, when used in conjunction with the information security objectives and controls in ISO/IEC 27002, is to create a common set of security categories and controls that can be implemented by a public cloud computing service provider acting as a PII processor. It has the following objectives:
Help the public cloud service provider to comply with applicable obligations whe |
https://en.wikipedia.org/wiki/Zoombombing | Zoombombing or Zoom raiding is the unwanted, disruptive intrusion, generally by Internet trolls, into a video-conference call. In a typical Zoombombing incident, a teleconferencing session is hijacked by the insertion of material that is lewd, obscene, or racist in nature, typically resulting in the shutdown of the session. The term is especially associated with and is derived from the name of the Zoom videoconferencing software program, but it has also been used to refer to the phenomenon on other video conferencing platforms. The term became popularized in 2020 when the COVID-19 pandemic forced many people to stay at home, and videoconferencing came to be used on a large scale by businesses, schools, and social groups.
Zoombombing has caused significant issues in particular for schools, companies, and organizations worldwide. Such incidents have resulted in increased scrutiny on Zoom as well as restrictions on usage of the platform by educational, corporate, and governmental institutions globally. In response, Zoom, citing the sudden influx of new users due to the COVID-19 pandemic, took measures to increase security of its teleconferencing application. Incidents of Zoombombing have prompted law enforcement officers in various countries to investigate such cases and file criminal charges for those responsible.
Procedure
The term "Zoombombing" is derived from the teleconferencing application Zoom, though the term has also been used in reference to similar incidents on other teleconferencing platforms, such as WebEx or Skype. The increased use of Zoom during the COVID-19 pandemic as an alternative to face-to-face meetings resulted in widespread exposure to hackers and Internet trolls, who exploit and work around the application's security features. In various forums such as Discord and Reddit, efforts have been coordinated to disrupt Zoom sessions, while certain Twitter accounts advertise meeting ids and passwords or meeting links (allowing users to instantly joi |
https://en.wikipedia.org/wiki/Taeha%20Types | Tae Ha Kim, known by his streaming channel Taeha Types, is a mechanical keyboard creator and livestreamer. While known for his commissioned keyboards, his Twitch livestream compose his primary occupation. His channel has influenced the rise of the mechanical keyboard hobby, particularly boosted by his viral video assembling a commission for Fortnite streamer Tfue.
Early life
Tae Ha Kim was born in and raised in California. Prior to streaming, he worked as a software engineer.
Streaming career
Kim began live streaming himself assembling mechanical keyboards in 2018. He was not the first creator to do so, but he focused on making his videos accessible to beginners and creating a platform for keyboard appreciation. The condensed cut of his livestream assembling a keyboard for Fortnite streamer Tfue became a viral hit, with two million views in under two weeks. Kim's Twitch channel is his primary occupation, where he is funded by donations and subscriptions, rather than by commissions. Kim has created keyboards by commission for other livestreamers, including LilyPichu. Tom's Hardware described Kim's popular livestream as being a significant contributor to the growth of the mechanical keyboard hobby.
Kim also makes ASMR typing videos and contributed to a vinyl record of mechanical keyboard sounds released on Trunk Records in 2019.
References
Further reading
Twitch (service) streamers
Computer keyboards
Year of birth missing (living people)
Living people |
https://en.wikipedia.org/wiki/IBM%20Enterprise%20Systems%20Architecture | IBM Enterprise Systems Architecture is an instruction set architecture introduced by IBM as ESA/370 in 1988. It is based on the IBM System/370-XA architecture.
It extended the dual-address-space mechanism introduced in later IBM System/370 models by adding a new mode in which general-purpose registers 1-15 are each associated with an access register referring to an address space, with instruction operands whose address is computed with a given general-purpose register as a base register will be in the address space referred to by the corresponding address register.
The later ESA/390, introduced in 1990, added a facility to allow device descriptions to be read using channel commands and, in later models, added instructions to perform IEEE 754 floating-point operations and increased the number of floating-point registers from 4 to 16.
Enterprise Systems Architecture is essentially a 32-bit architecture; as with System/360, System/370, and 370-XA, the general-purpose registers are 32 bits long, and the arithmetic instructions support 32-bit arithmetic. Only byte-addressable real memory (Central Storage) and Virtual Storage addressing is limited to 31 bits, as is the case with 370-XA. (IBM reserved the most significant bit to easily support applications expecting 24-bit addressing, as well as to sidestep a problem with extending two instructions to handle 32-bit unsigned addresses.) It maintains problem state backward compatibility dating back to 1964 with the 24-bit-address/32-bit-data (System/360 and System/370) and subsequent 24/31-bit-address/32-bit-data architecture (System/370-XA). However, the I/O subsystem is based on System/370 Extended Architecture (S/370-XA), not on the original S/370 I/O instructions.
ESA/370 architecture
On February 15, 1988, IBM announced
Enterprise Systems Architecture/370 (ESA/370) for 3090 enhanced ("E") models and for 4381 model groups 91E and 92E.
In addition to the primary-space and secondary-space addressing modes that later |
https://en.wikipedia.org/wiki/Chair%20tiling | In geometry, a chair tiling (or L tiling) is a nonperiodic substitution tiling created from L-tromino prototiles. These prototiles are examples of rep-tiles and so an iterative process of decomposing the L tiles into smaller copies and then rescaling them to their original size can be used to cover patches of the plane. Chair tilings do not possess translational symmetry, i.e., they are examples of nonperiodic tilings, but the chair tiles are not aperiodic tiles since they are not forced to tile nonperiodically by themselves. The trilobite and cross tiles are aperiodic tiles that enforce the chair tiling substitution structure and these tiles have been modified to a simple aperiodic set of tiles using matching rules enforcing the same structure. Barge et al. have computed the Čech cohomology of the chair tiling and it has been shown that chair tilings can also be obtained via a cut-and-project scheme.
References
External links
Tilings Encyclopedia, Chair
Aperiodic tilings |
https://en.wikipedia.org/wiki/Recovery%20Toolbox | Recovery Toolbox is a collection of utilities and online services for recovering corrupted files, file formats, and repairing passwords for various programs.
Free utilities
Recovery Toolbox for CD Free
Free tool for repairing data from compact discs that have been physically damaged (scratched, exposed to liquids, etc.) or are affected by system errors.
Recovery Toolbox File Undelete Free
Free tool for repairing deleted files in the Windows operating system. It supports the NTFS file system, but it doesn't support recovery of data stored on high performance disks (SSD).
Shareware utilities
Recovery Toolbox for Flash
Repairs deleted files from various storage media with FAT file systems, including SD, CF, MMC and other memory cards, smart media cards, IBM MicroDrives, Flash and USB drives, digital cameras, and floppy disks.
Recovery Toolbox for RAR
Repairs data from damaged RAR archives. Supports all existing RAR formats and compression ratios, password-protected archives, and archives stored on corrupted media.
Recovery Toolbox for Excel
Repairs corrupted Microsoft Excel files. Supports most tabular data, styles, fonts, sheets, formulas, functions, cell colors, borders, etc.
Recovery Toolbox for Outlook
Fixes errors encountered when working with Microsoft Outlook and repairs data such as emails, contacts, reminders, meetings, tasks, notes, calendar entries, logs, and other data from corrupted PST and OST files.
Web services
In addition to working as a specialized installed tool, Recovery Toolbox supports data repair via web services such as:
Adobe file formats: PDF documents and presentations (Adobe Acrobat/PDF Reader), AI image files (Adobe Illustrator), and PSD project files (Adobe Photoshop)
Microsoft Office file formats: Excel spreadsheets, Word documents (including RTF), PowerPoint presentations, Project files; and email formats: PST and OST (Outlook), and DBX(Outlook Express)
Other image file formats: DWG (AutoCAD) and CDR (CorelDraw)
Dat |
https://en.wikipedia.org/wiki/KeeWeb | KeeWeb is a free and open-source password manager compatible with KeePass, available as a web version and desktop apps. The underlying file format is KDBX (KeePass database file).
Technology
KeeWeb is written in JavaScript and uses WebCrypto and WebAssembly to process password files in the browser, without uploading them to a server. It can synchronize files with popular file hosting services, such as Dropbox, Google Drive, and OneDrive.
KeeWeb is also available as an Electron bundle which resembles a desktop app. The desktop version adds some features not available on web:
auto-typing passwords
ability to open and save local files
sync to WebDAV without CORS enabled
KeeWeb can also be deployed as a standalone server, or installed as a Nextcloud app.
Reception
KeeWeb was praised by Ghacks Technology News in 2016 as "brand-new" fixing the "shortcoming of a web-based version" of KeePass, and by Tech Advisor in 2020 as "well-designed cross-platform password manager".
See also
List of password managers
Password manager
Cryptography
References
External links
Cryptographic software
Free password managers
Password managers
Android (operating system) software
IOS software
Cross-platform free software (Linux; macOS; Windows) |
https://en.wikipedia.org/wiki/Predator%3A%20Hunting%20Grounds | Predator: Hunting Grounds is a multiplayer video game developed by IllFonic and published by Sony Interactive Entertainment for PlayStation 4 and Windows. It is part of the Predator franchise, featuring Arnold Schwarzenegger reprising his role as Alan "Dutch" Schafer (Predator), Alice Braga reprising her role as Isabelle (Predators), and Jake Busey reprising his role as Sean Keyes (The Predator).
Set in the remote jungles of the world, it tasks a team of four elite operatives with completing paramilitary operations before a single Predator can find and eliminate them. The game was released on April 24, 2020.
Predator: Hunting Grounds was the first Predator video game in a decade, following the Predators-themed mobile games from Angry Mob and Gameloft released in 2010, and the first full title for consoles since 2005's Predator: Concrete Jungle (although several other games featuring the Yautja were released in the interim).
Gameplay
Predator: Hunting Grounds is an asymmetrical multiplayer video game taking place in remote jungle locations. One player controls the Predator, while 4 others play as a team of special operations operators known as "Fireteam Voodoo" on a mission to collect intel or eliminate a drug lord until being forced to fight the Predator. The chief element is to either avoid being hunted by the Predator or capture and kill the Predator who in turn will be controlled by the player.
Objectives for Fireteam Voodoo include neutralizing computer-controlled NPC enemies, sabotaging their shipments and retrieving important VIP targets from them, as well as other special tasks. The game's maps offer various tactical opportunities for Fireteam players, from working together as a cohesive unit to splitting their force to reach their objectives. While this element of the game plays out, another player takes control of the Predator and tries to wipe out all of the special forces team members. If the human players manage to kill the Predator, their operation |
https://en.wikipedia.org/wiki/IHeart%20Living%20Room%20Concert%20for%20America | The iHeart Living Room Concert for America was a concert special held on March 29, 2020, by iHeartMedia in response to the COVID-19 pandemic; to provide relief and support to the public in an effort to combat the spread of COVID-19. The special aired on Fox and was simulcast across their sister cable networks, along with a number of iHeartRadio broadcast radio stations and within its mobile app.
Overview
The concert was hosted by Elton John, and it served as a partial replacement for the original timeslot for the 2020 iHeartRadio Music Awards, which was initially delayed to a later date and later cancelled due to the COVID-19 pandemic. It also served as a benefit for Feeding America and the First Responders Children's Foundation. The entire production utilized video conferencing and video apps from each artist and band who appeared to compile the special.
John, himself, volunteered to host the special, despite not having a piano in his Los Angeles home. Originally, Fox and iHeart were in talks with an undisclosed comedian to host the special, but it fell through.
It initially saw donations of nearly $8 million (and counting) raised for the charities. This was credited from not only numerous fan contributions, but also $500,000 from corporate partner Procter & Gamble, which Fox matched, and also additional funds raised by Fox employees and corporate partner PricewaterhouseCoopers. It was later reported that special eventually raised more $10 million for the charities as well.
Performances
Appearances
Melissa McCarthy and Ben Falcone
Ellen DeGeneres
Ryan Seacrest
Lady Gaga
Lizzo
Ciara and Russell Wilson
Broadcast
The special was broadcast at 9pm EST on Fox and was simulcast on Fox Corporation-owned networks Fox News, Fox Business, Fox Sports 2, and Fox Deportes. It was also broadcast on a majority of iHeartRadio broadcast radio stations, including its mobile app.
In Canada, the special was simulcast on Much, MTV, and CP24, wherein its broadcast benefits |
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