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https://en.wikipedia.org/wiki/Archimedes | Archimedes of Syracuse (, ; ) was an Ancient Greek mathematician, physicist, engineer, astronomer, and inventor from the ancient city of Syracuse in Sicily. Although few details of his life are known, he is regarded as one of the leading scientists in classical antiquity. Considered the greatest mathematician of ancient history, and one of the greatest of all time, Archimedes anticipated modern calculus and analysis by applying the concept of the infinitely small and the method of exhaustion to derive and rigorously prove a range of geometrical theorems. These include the area of a circle, the surface area and volume of a sphere, the area of an ellipse, the area under a parabola, the volume of a segment of a paraboloid of revolution, the volume of a segment of a hyperboloid of revolution, and the area of a spiral.
Archimedes' other mathematical achievements include deriving an approximation of pi, defining and investigating the Archimedean spiral, and devising a system using exponentiation for expressing very large numbers. He was also one of the first to apply mathematics to physical phenomena, working on statics and hydrostatics. Archimedes' achievements in this area include a proof of the law of the lever, the widespread use of the concept of center of gravity, and the enunciation of the law of buoyancy or Archimedes' principle. He is also credited with designing innovative machines, such as his screw pump, compound pulleys, and defensive war machines to protect his native Syracuse from invasion.
Archimedes died during the siege of Syracuse, when he was killed by a Roman soldier despite orders that he should not be harmed. Cicero describes visiting Archimedes' tomb, which was surmounted by a sphere and a cylinder that Archimedes requested be placed there to represent his mathematical discoveries.
Unlike his inventions, Archimedes' mathematical writings were little known in antiquity. Mathematicians from Alexandria read and quoted him, but the first comprehensi |
https://en.wikipedia.org/wiki/List%20of%20unsolved%20problems%20in%20astronomy | This article is a list of notable unsolved problems in astronomy. Some of these problems are theoretical, meaning that existing theories may be incapable of explaining certain observed phenomena or experimental results. Others are experimental, meaning that experiments necessary to test proposed theory or investigate a phenomenon in greater detail have not yet been performed. Some pertain to unique events or occurrences that have not repeated themselves and whose causes remain unclear.
Planetary astronomy
Our solar system
Orbiting bodies and rotation:
Are there any non-dwarf planets beyond Neptune?
Why do extreme trans-Neptunian objects have elongated orbits?
Rotation rate of Saturn:
Why does the magnetosphere of Saturn rotate at a rate close to that at which the planet's clouds rotate?
What is the rotation rate of Saturn's deep interior?
Satellite geomorphology:
What is the origin of the chain of high mountains that closely follows the equator of Saturn's moon, Iapetus?
Are the mountains the remnant of hot and fast-rotating young Iapetus?
Are the mountains the result of material (either from the rings of Saturn or its own ring) that over time collected upon the surface?
Extra-solar
How common are Solar System-like planetary systems? Some observed planetary systems contain Super-Earths and Hot Jupiters that orbit very close to their stars. Systems with Jupiter-like planets in Jupiter-like orbits appear to be rare. There are several possibilities why Jupiter-like orbits are rare, including that data is lacking or the grand tack hypothesis.
Stellar astronomy and astrophysics
Solar cycle:
How does the Sun generate its periodically reversing large-scale magnetic field?
How do other Sol-like stars generate their magnetic fields, and what are the similarities and differences between stellar activity cycles and that of the Sun?
What caused the Maunder Minimum and other grand minima, and how does the solar cycle recover from a minimum state?
Coronal heat |
https://en.wikipedia.org/wiki/Precision%20Lightweight%20GPS%20Receiver | The AN/PSN-11 Precision Lightweight GPS Receiver (PLGR, colloquially "plugger") is a ruggedized, hand-held, single-frequency GPS receiver fielded by the United States Armed Forces. It incorporates the Precise Positioning Service — Security Module (PPS-SM) to access the encrypted P(Y)-code GPS signal.
Introduced in January 1990, and extensively fielded until 2004 when it was replaced by its successor, the Defense Advanced GPS Receiver (DAGR). In that time period more than 165,000 PLGRs were procured worldwide, and despite being superseded by the DAGR, large numbers remain in unit inventories and it continues to be the most widely used GPS receiver in the United States military.
The PLGR measures 9.5 by 4.1 by 2.6 inches and weighs with batteries. It was originally delivered to the United States military with a six-year warranty; however, this was extended to ten years in June 2000.
Versions
AN/PSN-11 — NSN 5825-01-374-6643, an early version (tan case)
AN/PSN-11(V)1 "Enhanced PLGR" — NSN 5825-01-395-3513, an upgraded version (green case)
See also
Defense Advanced GPS Receiver
Selective availability anti-spoofing module |
https://en.wikipedia.org/wiki/Privacy-preserving%20computational%20geometry | Privacy-preserving computational geometry is the research area on the intersection of the domains of secure multi-party computation (SMC) and computational geometry. Classical problems of computational geometry reconsidered from the point of view of SMC include shape intersection, private point inclusion problem, range searching, convex hull, and more.
A pioneering work in this area was a 2001 paper by Atallah and Du, in which the secure point in polygon inclusion and polygonal intersection problems were considered.
Other problems are computation of the distance between two private points and secure two-party point-circle inclusion problem.
Problem statements
The problems use the conventional "Alice and Bob" terminology. In all problems the required solution is a protocol of information exchange during which no additional information is revealed beyond what may be inferred from the answer to the required question.
Point-in-polygon: Alice has a point a, and Bob has a polygon B. They need to determine whether a is inside B.
Polygon pair intersection: Alice has a polygon A, and Bob has a polygon B. They need to determine whether A intersects B. |
https://en.wikipedia.org/wiki/Superconvergence | In numerical analysis, a superconvergent or supraconvergent method is one which converges faster than generally expected (superconvergence or supraconvergence). For example, in the Finite Element Method approximation to Poisson's equation in two dimensions, using piecewise linear elements, the average error in the gradient is first order. However under certain conditions it's possible to recover the gradient at certain locations within each element to second order. |
https://en.wikipedia.org/wiki/Descriptive%20notation | Descriptive notation is a chess notation system based on abbreviated natural language. Its distinctive features are that it refers to files by the piece that occupies the back rank square in the starting position and that it describes each square two ways depending on whether it is from White or Black's point of view. It was common in English, Spanish and French chess literature until about 1980. In most other languages, the more concise algebraic notation was in use. Since 1981, FIDE no longer recognizes descriptive notation for the purposes of dispute resolution, and algebraic notation is now the accepted international standard.
Description
Nomenclature
With the exception of the knight, each piece is abbreviated as the first letter of its name: K for king, Q for queen, R for rook, B for bishop, and P for pawn. As knight begins with the same letter as king, it is abbreviated as either N or Kt, the former being the modern convention. In 1944, Chess Review received many letters debating the change from Kt to N.
Each square has two names, depending on the viewpoint of White or Black. Each is given a name corresponding to the piece that occupies the first at the start of the game. Thus, in English descriptive notation the queen's file is named "Q" and the king's file is named "K". Since there are two each of the remaining pieces on the first rank, it is necessary to distinguish between them. The pieces on the queen's side of the board (to White's left; to Black's right) are named with respect to the queen, i.e. "queen's rook", "queen's knight" and "queen's bishop"; and have the shortened names "QR", "QN" and "QB", respectively. Similarly, the pieces on the king's side (White's right; Black's left) are named with respect to the king, i.e. "king's rook", "king's knight" and "king's bishop"; and have the shortened names "KR", "KN" and "KB". The rank is given a number, ranging from 1 to 8, with rank 1 being closest to the player.
This method of naming the squares me |
https://en.wikipedia.org/wiki/Ol%20Onal | The Ol Onal is an alphabetic writing system for the Bhumij language. Ol Onal script was created between 1981 and 1992 by Ol Guru Mahendra Nath Sardar. Ol Onal script is used to write the Bhumij language in some parts of West Bengal, Jharkhand, Orissa, and Assam.
History
The Ol Onal script was created in between 1981 and 1992 by Mahendra Nath Sardar for the Bhumij language.
The Bhumij community had no written language, and knowledge was transmitted orally from one generation to another. Later researchers started to use Devanagari, Bengali, and Odia scripts to document the Bhumij language. However, Bhumijs did not have their own script. Sardar's invention of the Ol Onal script enriched the cultural identity of the tribal Bhumij community. He wrote many text books in the Ol Onal script.
Language
Bhumij is the language of the Munda subfamily of the Austroasiatic languages, related to Ho, Mundari and Santali, spoken mainly in the Indian states Jharkhand, Odisha and West Bengal. It is spoken by around 100,000 people in India.
See also
Bhumij
Bhumij language |
https://en.wikipedia.org/wiki/Beck%E2%80%93Fiala%20theorem | In mathematics, the Beck–Fiala theorem is a major theorem in discrepancy theory due to József Beck and Tibor Fiala. Discrepancy is concerned with coloring elements of a ground set such that each set in a certain set system is as balanced as possible, i.e., has approximately the same number of elements of each color. The Beck–Fiala theorem is concerned with the case where each element doesn't appear many times across all sets. The theorem guarantees that if each element appears at most times, then the elements can be colored so that the imbalance is at most .
Statement
Formally, given a universe
and a collection of subsets
such that for each ,
then one can find an assignment
such that
Proof sketch
The proof is based on a simple linear-algebraic argument. Start with for all elements and call all variables active in the beginning.
Consider only sets with . Since each element appears at most times in a set, there are less than such sets. Now, enforce linear constraints for them. Since it is a non-trivial linear subspace of with fewer constraints than variables, there is a non-zero solution. Normalize this solution, and at least one of the values is either . Set this value and inactivate this variable. Now, ignore the sets with less than active variables. And repeat the same procedure enforcing the linear constraints that the sum of active variables of each remaining set is still the same. By the same counting argument, there is a non-trivial solution, so one can take linear combinations of this with the original one until some element becomes . Repeat until all variables are set.
Once a set is ignored, the sum of the values of its variables is zero and there are at most unset variables. The change in those can increase to at most . |
https://en.wikipedia.org/wiki/Ecological%20yield | Ecological yield is the harvestable population growth of an ecosystem. It is most commonly measured in forestry: sustainable forestry is defined as that which does not harvest more wood in a year than has grown in that year, within a given patch of forest.
However, the concept is also applicable to water, soil, and any other aspect of an ecosystem which can be both harvested and renewed—called renewable resources. The carrying capacity of an ecosystem is reduced over time if more than the amount which is "renewed" (refreshed or regrown or rebuilt) is consumed.
Ecosystem services analysis calculates the global yield of the Earth's biosphere to humans as a whole. This is said to be greater in size than the entire human economy. However, it is more than just yield, but also the natural processes that increase biodiversity and conserve habitat which result in the total value of these services. "Yield" of ecological commodities like wood or water, useful to humans, is only a part of it.
Very often an ecological yield in one place offsets an ecological load in another. Greenhouse gas released in one place, for instance, is fairly evenly distributed in the atmosphere, and so greenhouse gas control can be achieved by creating a carbon sink literally anywhere else.
History
Some of the earliest academic papers on the subject were researching methods of sustainable fishing. Work of Russel et al. in 1931 observed in particular that ”it appears that the ideal of a stabilised fishery yielding a constant maximum value is impractical.” This work was mostly theoretical. Practical work would begin later, performed by industry and government agencies.
Motivation
Ecological yield is a theoretical construct which aggregates information from several physically measurable quantities. It can be used to reason about other ecological indicators such as the footprint. It can also be used as a decision-making tool for governments and corporations.
Ecological footprint
The idea o |
https://en.wikipedia.org/wiki/Cymodocea%20nodosa | Cymodocea nodosa is a species of seagrass in the family Cymodoceaceae and is sometimes known as little Neptune grass. As a seagrass, it is restricted to growing underwater and is found in shallow parts of the Mediterranean Sea and certain adjoining areas of the Atlantic Ocean.
Description
C. nodosa has light green or greyish-green leaves. They are very narrow but may be up to forty centimetres long. Each leaf has seven to nine veins running along its length. The plant produces rhizomes which are only 1 mm in diameter and have leaf scars at intervals. Inconspicuous grass-like flowers are sometimes produced at the end of long stems in the spring when water temperatures begin to rise after their winter minimum. The pollen is liberated into the sea and the seeds remain dormant until the following spring.
Distribution and habitat
This seagrass is found in shallow parts of the Mediterranean Sea and the adjoining parts of the Atlantic Ocean, the coasts of Portugal, Mauritania and Senegal and round the Canary Islands, Madeira and the islands of Cape Verde. It grows at depths of down to nineteen metres in sandy sediments in sheltered locations and needs clear waters for photosynthesis. Off the Catalan coast in the western Mediterranean, a single meadow of this grass covering at least has been discovered.
Ecology
Cymodocea nodosa grows in meadows on the seabed and is sometimes associated with the other seagrasses, Zostera noltei and Posidonia oceanica and the seaweeds Caulerpa prolifera and Caulerpa racemosa. Although it is adversely affected by mechanical disturbance such as trawling and by pollution, and although it is in competition with other seagrass species, C. nodosa is not considered to be threatened.
In the Canary Islands, fifty-three species of epiphytic algae were found to grow on the leaves and rhizomes of C. nodosa. Many of these were encrusting species of Corallinaceae.
Seagrass meadows have high biological productivity and are rich, biodiverse habitats. |
https://en.wikipedia.org/wiki/Thermal%20hydraulics | Thermal hydraulics (also called thermohydraulics) is the study of hydraulic flow in thermal fluids. The area can be mainly divided into three parts: thermodynamics, fluid mechanics, and heat transfer, but they are often closely linked to each other. A common example is steam generation in power plants and the associated energy transfer to mechanical motion and the change of states of the water while undergoing this process. Thermal-hydraulic analysis can determine important parameters for reactor design such as plant efficiency and coolability of the system.
The common adjectives are "thermohydraulic", "thermal-hydraulic" and "thermalhydraulic".
Thermodynamic analysis
In the thermodynamic analysis, all states defined in the system are assumed to be in thermodynamic equilibrium; each state has mechanical, thermal, and phase equilibrium, and there is no macroscopic change with respect to time. For the analysis of the system, the first law and second law of thermodynamics can be applied.
In power plant analysis, a series of states can comprise a cycle. In this case, each state represents condition at the inlet/outlet of individual component. The example of components are pumpcompressor, turbine, reactor, and heat exchanger. By considering the constitutive equation for the given type of fluid, thermodynamic state of each point can be analyzed. As a result, the thermal efficiency of the cycle can be defined.
Examples of the cycle include the Carnot cycle, Brayton cycle, and Rankine cycle. Based on the simple cycle, modified or combined cycle also exists.
Thermo-Hydraulic Improvement Parameter (THIP)
Authors (Sahu et al.[6])observe that Thermo-hydraulic Parameter (THP) is less sensitive towards the Friction Factor Improvement Factor (FFER). The deviation between the terms (fR/fS) and (fR/fS)0.33 has been found 48 % to 64 % for the range of roughness and other parameters with (Re) 2900 – 14,000, which has been used for the present study.
Therefore, in order to eval |
https://en.wikipedia.org/wiki/Random%20regular%20graph | A random r-regular graph is a graph selected from , which denotes the probability space of all r-regular graphs on vertices, where and is even. It is therefore a particular kind of random graph, but the regularity restriction significantly alters the properties that will hold, since most graphs are not regular.
Properties of random regular graphs
As with more general random graphs, it is possible to prove that certain properties of random –regular graphs hold asymptotically almost surely. In particular, for , a random r-regular graph of large size is asymptotically almost surely r-connected. In other words, although –regular graphs with connectivity less than exist, the probability of selecting such a graph tends to 0 as increases.
If is a positive constant, and is the least integer satisfying
then, asymptotically almost surely, a random r-regular graph has diameter at most d. There is also a (more complex) lower bound on the diameter of r-regular graphs, so that almost all r-regular graphs (of the same size) have almost the same diameter.
The distribution of the number of short cycles is also known: for fixed , let be the number of cycles of lengths up to . Then the are asymptotically independent Poisson random variables with means
Algorithms for random regular graphs
It is non-trivial to implement the random selection of r-regular graphs efficiently and in an unbiased way, since most graphs are not regular. The pairing model (also configuration model) is a method which takes nr points, and partitions them into n buckets with r points in each of them. Taking a random matching of the nr points, and then contracting the r points in each bucket into a single vertex, yields an r-regular graph or multigraph. If this object has no multiple edges or loops (i.e. it is a graph), then it is the required result. If not, a restart is required.
A refinement of this method was developed by Brendan McKay and Nicholas Wormald. |
https://en.wikipedia.org/wiki/Dendronized%20polymer | Dendronized polymers (or dendronised polymers) are linear polymers to every repeat unit of which dendrons are attached. Dendrons are regularly branched, tree-like fragments and for larger ones the polymer backbone is wrapped to give sausage-like, cylindrical molecular objects. Figure 1 shows a cartoon representation with the backbone in red and the dendrons like cake slices in green. It also provides a concrete chemical structure showing a polymethylmethacrylate (PMMA) backbone, the methyl group of which is replaced by a dendron of the third generation (three consecutive branching points).
Figure 1. Cartoon representation (left) and a concrete example of a third generation dendronized polymer (right). The peripheral amine groups are modified by a substituent X which often is a protection group. Upon deprotection and modification substantial property changes can be achieved. The subscript n denotes the number of repeat units.
Structure and applications
Dendronized polymers can contain several thousands of dendrons in one macromolecule and have a stretched out, anisotropic structure. In this regard they differ from the more or less spherically shaped dendrimers, where a few dendrons are attached to a small, dot-like core resulting in an isotropic structure. Depending on dendron generation, the polymers differ in thickness as the atomic force microscopy image shows (Figure 2). Neutral and charged dendronized polymers are highly soluble in organic solvents and in water, respectively. This is due to their low tendency to entangle. Dendronized polymers have been synthesized with, e.g., polymethylmethacrylate, polystyrene, polyacetylene, polyphenylene, polythiophene, polyfluorene, poly(phenylene vinylene), poly(phenylene acetylene), polysiloxane, polyoxanorbornene, poly(ethylene imine) (PEI) backbones. Molar masses up to 200,000,000 g/mol have been obtained. Dendronized polymers have been investigated for/as bulk structure control, responsivity to external stimuli, sing |
https://en.wikipedia.org/wiki/EbXML | Electronic Business using eXtensible Markup Language, commonly known as e-business XML, or ebXML (pronounced ee-bee-ex-em-el, [i'bi,eks,em'el]) as it is typically referred to, is a family of XML based standards sponsored by OASIS and UN/CEFACT whose mission is to provide an open, XML-based infrastructure that enables the global use of electronic business information in an interoperable, secure, and consistent manner by all trading partners.
The ebXML architecture is a unique set of concepts; part theoretical and part implemented in the existing ebXML standards work.
The ebXML work stemmed from earlier work on ooEDI (object oriented EDI), UML / UMM, XML markup technologies and the X12 EDI "Future Vision" work sponsored by ANSI X12 EDI.
The melding of these components began in the original ebXML work and the theoretical discussion continues today. Other work relates, such as the Object Management Group work and the OASIS BCM (Business-Centric Methodology) standard (2006).
Conceptual overview of ebXML architecture
While the ebXML standards adopted by ISO and OASIS seek to provide formal XML-enabled mechanisms that can be implemented directly, the ebXML architecture is on concepts and methodologies that can be more broadly applied to allow practitioners to better implement e-business solutions.
A particular instance is the Core Components Technical Specification (CCTS) work that continues within UN/CEFACT, whereas its cousin - UBL - Universal Business Language - specification is used within OASIS that implements specific XML transactions by applying the principles of CCTS to typical supply chain transactions such as invoice, purchase order, ship notice and so on.
History
ebXML was started in 1999 as a joint initiative between the United Nations Centre for Trade facilitation and Electronic Business (UN/CEFACT) and Organization for the Advancement of Structured Information Standards (OASIS). A joint coordinating committee composed of representatives from each of |
https://en.wikipedia.org/wiki/Vampire%20Killer | Vampire Killer, known in Japan as is a platform video game developed and published by Konami for the MSX2 in 1986. It is a parallel version of the original Castlevania, which debuted a month earlier for the Famicom Disk System under the same Japanese title. However, the MSX2 version was localized first in Europe and was published without the Castlevania branding that the franchise would start using abroad in 1987 when the NES version was released in North America (where neither Vampire Killer nor the MSX2 platform were released). It was released on the Wii U's Virtual Console on December 17, 2014 in Japan.
Like in Castlevania, the player controls vampire hunter Simon Belmont, who ventures into Dracula's castle armed with a mystical whip inherited from his father, in order to slay the evil count.
Gameplay
While Vampire Killer shares the same premise, soundtrack, characters and locations as the original Castlevania, the structure of the game and its play mechanics differ significantly from its NES counterpart. Like Castlevania, Vampire Killer consists of 18 stages, with a boss encounter at the end of every third stage. But in contrast to the linear level designs in Castlevania, Vampire Killer features more labyrinth-like stages, requiring the player to seek out the exit to the next stage and find the skeleton key required to unlock it. Due to the hardware limitations of the MSX2, Vampire Killer uses flip screens instead of scrolling. The game can be played with a keyboard or a game controller.
Items and weapons can be obtained by breaking through candle stands and certain walls like in the NES version, and by purchasing them from merchants hidden throughout the castle or by unlocking treasure chests using keys. Simon's default whip can be replaced with one of four weapons: a chain whip, throwing daggers, a battle ax, and a battle cross - the latter two function both like a boomerang and must be retrieved on their return path if the player wishes to preserve them.
|
https://en.wikipedia.org/wiki/Molakolukulu | Sanna, laavu Molakolukulu (molagolukulu) is a variety of rice cultivated in Andhra Pradesh in India. This variety is often called nellore molakolukulu perhaps due to its origin in the Nellore region of Andhra Pradesh. It has been a popular variety in Nellore, and has been formally developed into better varieties since 1937.
The variety is known for improved capacity in handling monsoon season rainfall. However its popularity has diminished due to farmer's moving to grow shorter duration crops. |
https://en.wikipedia.org/wiki/Modal%20companion | In logic, a modal companion of a superintuitionistic (intermediate) logic L is a normal modal logic that interprets L by a certain canonical translation, described below. Modal companions share various properties of the original intermediate logic, which enables to study intermediate logics using tools developed for modal logic.
Gödel–McKinsey–Tarski translation
Let A be a propositional intuitionistic formula. A modal formula T(A) is defined by induction on the complexity of A:
for any propositional variable ,
As negation is in intuitionistic logic defined by , we also have
T is called the Gödel translation or Gödel–McKinsey–Tarski translation. The translation is sometimes presented in slightly different ways: for example, one may insert before every subformula. All such variants are provably equivalent in S4.
Modal companions
For any normal modal logic M that extends S4, we define its si-fragment ρM as
The si-fragment of any normal extension of S4 is a superintuitionistic logic. A modal logic M is a modal companion of a superintuitionistic logic L if .
Every superintuitionistic logic has modal companions. The smallest modal companion of L is
where denotes normal closure. It can be shown that every superintuitionistic logic also has a largest modal companion, which is denoted by σL. A modal logic M is a companion of L if and only if .
For example, S4 itself is the smallest modal companion of intuitionistic logic (IPC). The largest modal companion of IPC is the Grzegorczyk logic Grz, axiomatized by the axiom
over K. The smallest modal companion of classical logic (CPC) is Lewis' S5, whereas its largest modal companion is the logic
More examples:
Blok–Esakia isomorphism
The set of extensions of a superintuitionistic logic L ordered by inclusion forms a complete lattice, denoted ExtL. Similarly, the set of normal extensions of a modal logic M is a complete lattice NExtM. The companion operators ρM, τL, and σL can be considered as mappings between the latt |
https://en.wikipedia.org/wiki/%CE%A9-automaton | In automata theory, a branch of theoretical computer science, an ω-automaton (or stream automaton) is a variation of finite automata that runs on infinite, rather than finite, strings as input. Since ω-automata do not stop, they have a variety of acceptance conditions rather than simply a set of accepting states.
ω-automata are useful for specifying behavior of systems that are not expected to terminate, such as hardware, operating systems and control systems. For such systems, one may want to specify a property such as "for every request, an acknowledge eventually follows", or its negation "there is a request that is not followed by an acknowledge". The former is a property of infinite words: one cannot say of a finite sequence that it satisfies this property.
Classes of ω-automata include the Büchi automata, Rabin automata, Streett automata, parity automata and Muller automata, each deterministic or non-deterministic. These classes of ω-automata differ only in terms of acceptance condition. They all recognize precisely the regular ω-languages except for the deterministic Büchi automata, which is strictly weaker than all the others. Although all these types of automata recognize the same set of ω-languages, they nonetheless differ in succinctness of representation for a given ω-language.
Deterministic ω-automata
Formally, a deterministic ω-automaton is a tuple A = (Q,Σ,δ,Q0,Acc) that consists of the following components:
Q is a finite set. The elements of Q are called the states of A.
Σ is a finite set called the alphabet of A.
δ: Q × Σ → Q is a function, called the transition function of A.
Q0 is an element of Q, called the initial state.
Acc is the acceptance condition, formally a subset of Qω.
An input for A is an infinite string over the alphabet Σ, i.e. it is an infinite sequence α = (a1,a2,a3,...).
The run of A on such an input is an infinite sequence ρ = (r0,r1,r2,...) of states, defined as follows:
r0 = q0.
r1 = δ(r0,a1).
r2 = δ(r1,a2).
...
th |
https://en.wikipedia.org/wiki/Positive%20and%20negative%20parts | In mathematics, the positive part of a real or extended real-valued function is defined by the formula
Intuitively, the graph of is obtained by taking the graph of , chopping off the part under the x-axis, and letting take the value zero there.
Similarly, the negative part of f is defined as
Note that both f+ and f− are non-negative functions. A peculiarity of terminology is that the 'negative part' is neither negative nor a part (like the imaginary part of a complex number is neither imaginary nor a part).
The function f can be expressed in terms of f+ and f− as
Also note that
.
Using these two equations one may express the positive and negative parts as
Another representation, using the Iverson bracket is
One may define the positive and negative part of any function with values in a linearly ordered group.
The unit ramp function is the positive part of the identity function.
Measure-theoretic properties
Given a measurable space (X,Σ), an extended real-valued function f is measurable if and only if its positive and negative parts are. Therefore, if such a function f is measurable, so is its absolute value |f|, being the sum of two measurable functions. The converse, though, does not necessarily hold: for example, taking f as
where V is a Vitali set, it is clear that f is not measurable, but its absolute value is, being a constant function.
The positive part and negative part of a function are used to define the Lebesgue integral for a real-valued function. Analogously to this decomposition of a function, one may decompose a signed measure into positive and negative parts — see the Hahn decomposition theorem.
See also
Rectifier (neural networks)
Even and odd functions
Real and imaginary parts |
https://en.wikipedia.org/wiki/Institut%20d%27Astrophysique%20de%20Paris | The Institut d'Astrophysique de Paris (translated: Paris Institute of Astrophysics) is a research institute in Paris, France. The Institute is part of the Sorbonne University and is associated with the CNRS Centre national de la recherche scientifique. It is located at 98bis, Boulevard Arago Il in the 14th arrondissement of Paris, adjacent to the Paris Observatory.
History
The IAP was created in 1936 by the French ministry of education under Jean Zay, initially for the purpose of processing data received from the Observatory of Haute-Provence, which was created at the same time. Construction of the building started on 6 January 1938. On 15 June 1939, Henri Mineur became the institute's first director. IAP scientists were at first located in Paris Observatory, then in the École normale supérieure de Paris before arriving in the current building in 1944 which was finally completed in 1952.
Current research
The IAP includes 160 researchers, engineers, technicians, and administrators and regularly welcomes many visitors and students.
The main areas of research at the IAP are:
General relativity and cosmology
Cosmological structure formation
High-energy astrophysics
Origin and evolution of galaxies
Stellar structure
Exoplanets
The IAP is one of five laboratories of AERA, the European association for research in astronomy. The laboratory is situated at the interface between two disciplines, astrophysics and theoretical physics. The International Astronomical Union has its seat at the IAP.
Directors
1936-1954 : Henri Mineur
1954-1960 : André Danjon
1960-1971 : André Lallemand
1972-1977 : Jean-Claude Pecker
1978-1989 : Jean Audouze
1990-1998 : Alain Omont
1998-2004 : Bernard Fort
2005-2013 : Laurent Vigroux
Since 2014 : Francis Bernardeau |
https://en.wikipedia.org/wiki/Manz | Manz AG (formerly Manz Automation) is a German multinational engineering company active in the fields of automation, laser processesing, metrology, wet chemistry and roll-to-roll processing. Manz AG bundles its activities into two reporting segments: Mobility & Battery Solutions and Industry Solutions. The focus in the Mobility & Battery Solutions segment is on intelligent production solutions for highly efficient lithium-ion batteries. The Industry Solutions reporting segment is responsible for assembly and production solutions for electronic components and devices, power and consumer electronics, and components for the electric powertrain.
Headquartered in Reutlingen, Baden-Württemberg, the company has additional production centres in Tübingen as well as international manufacturing sites in Hungary, Italy, Slovakia, China and Taiwan. There are additional sales and service branches in the United States, South Korea and India.
Manz had developed a significant presence in the solar photovoltaic industry. Its activities in this sector focused on the development and supply of integrated systems for the production of CIGS thin-film solar modules. In 2010 the company established a partnership with Würth Solar (part of the Würth industrial group) for the exclusive licensing of its CIGS solar cell production technology. After the acquisition of the CIGS modules innovation line of Würth Solar in January 2012, technology licenses were also transferred to the company on an unrestricted basis. In September 2012, Manz presented a CIGS solar module, which was produced on a mass production line and has a 14.6 percent efficiency on total module area and 15.9 percent on aperture area (one in the industry unequaled efficiency). In April 2015, Manz surpassed these numbers again and presented an impressive new efficiency world record for CIGS thin-film solar modules on mass production line with a module efficiency of 16 percent.
The major business areas of Manz are the supply of sy |
https://en.wikipedia.org/wiki/Read-once%20function | In mathematics, a read-once function is a special type of Boolean function that can be described by a Boolean expression in which each variable appears only once.
More precisely, the expression is required to use only the operations of logical conjunction, logical disjunction, and negation. By applying De Morgan's laws, such an expression can be transformed into one in which negation is used only on individual variables (still with each variable appearing only once). By replacing each negated variable with a new positive variable representing its negation, such a function can be transformed into an equivalent positive read-once Boolean function, represented by a read-once expression without negations.
Examples
For example, for three variables , , and , the expressions
, and
are all read-once (as are the other functions obtained by permuting the variables in these expressions). However, the Boolean median operation, given by the expression
is not read-once: this formula has more than one copy of each variable, and there is no equivalent formula that uses each variable only once.
Characterization
The disjunctive normal form of a (positive) read-once function is not generally itself read-once. Nevertheless, it carries important information about the function. In particular, if one forms a co-occurrence graph in which the vertices represent variables, and edges connect pairs of variables that both occur in the same clause of the conjunctive normal form, then the co-occurrence graph of a read-once function is necessarily a cograph. More precisely, a positive Boolean function is read-once if and only if its co-occurrence graph is a cograph, and in addition every maximal clique of the co-occurrence graph forms one of the conjunctions (prime implicants) of the disjunctive normal form. That is, when interpreted as a function on sets of vertices of its co-occurrence graph, a read-once function is true for sets of vertices that contain a maximal clique, and false otherwi |
https://en.wikipedia.org/wiki/Dipole%20field%20strength%20in%20free%20space | Dipole field strength in free space, in telecommunications, is the electric field strength caused by a half wave dipole under ideal conditions. The actual field strength in terrestrial environments is calculated by empirical formulas based on this field strength.
Power density
Let N be the effective power radiated from an isotropic antenna and p be the power density at a distance d from this source
Power density is also defined in terms of electrical field strength;
Let E be the electrical field and Z be the impedance of the free space
The following relation is obtained by equating the two,
or by rearranging the terms
Numerical values
Impedance of free space is roughly
Since a half wave dipole is used, its gain over an isotropic antenna ( ) should also be taken into consideration,
In this equation SI units are used.
Expressing the same equation in:
kW instead of W in power,
km instead of m in distance and
mV/m instead of V/m in electric field
is equivalent to multiplying the expression on the right by . In this case,
See also
Antennas
Effective radiated power
Electric field
Field strength meter
Radio propagation model |
https://en.wikipedia.org/wiki/Separation%20of%20concerns | In computer science, separation of concerns is a design principle for separating a computer program into distinct sections. Each section addresses a separate concern, a set of information that affects the code of a computer program. A concern can be as general as "the details of the hardware for an application", or as specific as "the name of which class to instantiate". A program that embodies SoC well is called a modular program. Modularity, and hence separation of concerns, is achieved by encapsulating information inside a section of code that has a well-defined interface. Encapsulation is a means of information hiding. Layered designs in information systems are another embodiment of separation of concerns (e.g., presentation layer, business logic layer, data access layer, persistence layer).
Separation of concerns results in more degrees of freedom for some aspect of the program's design, deployment, or usage. Common among these is increased freedom for simplification and maintenance of code. When concerns are well-separated, there are more opportunities for module upgrade, reuse, and independent development. Hiding the implementation details of modules behind an interface enables improving or modifying a single concern's section of code without having to know the details of other sections and without having to make corresponding changes to those other sections. Modules can also expose different versions of an interface, which increases the freedom to upgrade a complex system in piecemeal fashion without interim loss of functionality.
Separation of concerns is a form of abstraction. As with most abstractions, separating concerns means adding additional code interfaces, generally creating more code to be executed. So despite the many benefits of well-separated concerns, there is often an associated execution penalty.
Implementation
The mechanisms for modular or object-oriented programming that are provided by a programming language are mechanisms that allow d |
https://en.wikipedia.org/wiki/Civilization%27s%20Waiting%20Room | Sivilisasjonens venterom (Norwegian for "Civilization's Waiting Room") was a research larp (live-action roleplaying game) held in Bergen in November 2021. It was designed to explore the potential of larps as a research methodology and as research dissemination, and was specifically intended to investigate ethical questions that arise when encountering new surveillance technologies.
Background
The project was funded by the Research Council of Norway as part of a scheme to increase the Norwegian impact of EU-funded research. The stated goal was to "create arenas where the general public can practice making ethical decisions about the use of new technologies, specifically machine vision technologies such as facial recognition, deepfakes and VR"
The creative lead for the project was veteran larp developer Anita Myhre Andersen, working with Harald Misje, Jon Andreas Edland, Toril Mjelva Saatvedt, Sebastian Sjøvold and Eskil Mjelva Saatvedt. The researchers in the development team were Marianne Gunderson, Kristian A. Bjørkelo, and Jill Walker Rettberg, who had initiated the project.
The larp drew upon the Nordic larp genre as well as on research on educational larping (Edu-larp) and larps as research tools. In a scholarly paper about Sivilisasjonens venterom, Malthe Stavning Erslev describes it as a research larp, which is "a method of academic knowledge development in its own right".
Setting and gameplay
Civilization's Waiting Room was set in a future where society has unravelled due to climate change and war. The Civilization (Sivilisasjonen) is a city state that is a rare refuge from the surrounding wilderness. It is run by a benevolent AI known as Intelligensen ("the Intelligence") that bases all of its decisions on the sum of all the opinions and interests of the citizens, as it interprets these based on the extensive data it collects and is fed by the citizens. Sivilisasjonen was therefore imagined as an AI-based democracy.
The overall story arc of Sivilisasj |
https://en.wikipedia.org/wiki/Michael%20Lissack | Michael Lissack (born 1958) is an American business executive, author, business consultant and former director of the Institute for the Study of Coherence and Emergence. In 2019 Lissack was inducted into the International Academy for Systems and Cybernetic Sciences.
Lissack was managing director in the municipal bond department at Smith Barney, and came into prominence as the whistleblower, who exposed a yield burning scandal in the 1990s, whereby financial firms made illegal profits from the structuring of U.S. government investment portfolios associated with municipal bonds.
Biography
Lissack received his BA in American Civilization and Political Economy in 1979 from Williams College, and his MPPM in Business from Yale University in 1981. Later in his career in 2000 Lissack received a doctor of business administration degree from Henley Management College in the United Kingdom.
After his graduation from Yale, Lissack started at Smith Barney, where he became managing director and served in this position until 1995. From 1999 - 2017 he was the director of the Institute for the Study of Coherence and Emergence. From 1999 to 2004, Lissack also served as the editor-in-chief of Emergence: A Journal of Complexity Issues in Organizations and Management now known as E:CO.
Lissack was a candidate for county commissioner in Collier County, Florida, in 2002 and in 2006. He briefly taught business and public policy at the Central European University. Lissack was the president of the American Society for Cybernetics from 2015 to 2020.
Work and controversies
Praise for Lissack
In 1999 Worth Magazine described Lissack as one of "Wall Street's 25 smartest players" and as one of the 100 Americans who have most influenced "how we think about money" in 2001.
Yield burning scandal
In 1994, Lissack exposed a major yield burning scandal on Wall Street. The issue was eventually settled by a number of firms for over $200 million, to which Lissack was entitled to at least 15% |
https://en.wikipedia.org/wiki/Hypoallergenic | Hypoallergenic, meaning "below average" or "slightly" allergenic, is a term meaning that something (usually cosmetics, pets, textiles, food, etc.) causes fewer allergic reactions. The term was first used in 1953 in an advertising campaign for cosmetics or perhaps as early as 1940. A 2017 study of the top-selling skin moisturizers from Amazon, Target, and Walmart found 83% of those marketed as "hypoallergenic" contained at least one potentially allergenic chemical.
The term is also commonly applied to pet breeds which are claimed to produce fewer allergens than other breeds of the same species, due to some combination of their coat type, absence of fur, or absence of a gene that produces a certain protein. All breeds still produce allergens and a 2011 study failed to find a difference in allergen concentrations in homes with dogs of "hypoallergenic breeds" and other breeds.
Certifications and definitions
Some cosmetics are marketed as hypoallergenic to imply that their use is less likely to lead to an allergic reaction than other products. However, the term hypoallergenic is not regulated, and no research has been done showing that products labeled hypoallergenic are less problematic than any others. In 1975, the US Food and Drug Administration tried to regulate the term hypoallergenic, but the proposal was challenged by cosmetic companies Clinique and Almay in the United States Court of Appeals for the District of Columbia. In 1977, courts overruled the U.S. Food and Drug Administration's regulation of the use of the term hypoallergenic. In 2019, the European Union released a document about claims made concerning cosmetics, but this was issued as guidance, not a regulation.
In some countries, there are allergy interest groups that provide manufacturers with a certification procedure including tests that ensure a product is unlikely to cause an allergic reaction, but such products are usually described and labeled using other but similar terms. So far, public aut |
https://en.wikipedia.org/wiki/Permissible%20stress%20design | Permissible stress design is a design philosophy used by mechanical engineers and civil engineers.
The civil designer ensures that the stresses developed in a structure due to service loads do not exceed the elastic limit. This limit is usually determined by ensuring that stresses remain within the limits through the use of factors of safety.
In structural engineering, the permissible stress design approach has generally been replaced internationally by limit state design (also known as ultimate stress design, or in USA, Load and Resistance Factor Design, LRFD) as far as structural engineering is considered, except for some isolated cases.
In USA structural engineering construction, allowable stress design (ASD) has not yet been completely superseded by limit state design except in the case of Suspension bridges, which changed from allowable stress design to limit state design in the 1960s. Wood, steel, and other materials are still frequently designed using allowable stress design, although LRFD is probably more commonly taught in the USA university system.
In mechanical engineering design such as design of pressure equipment, the method uses the actual loads predicted to be experienced in practice to calculate stress and deflection. Such loads may include pressure thrusts and the weight of materials. The predicted stresses and deflections are compared with allowable values that have a "factor" against various failure mechanisms such as leakage, yield, ultimate load prior to plastic failure, buckling, brittle fracture, fatigue, and vibration/harmonic effects. However, the predicted stresses almost always assumes the material is linear elastic. The "factor" is sometimes called a factor of safety, although this is technically incorrect because the factor includes allowance for matters such as local stresses and manufacturing imperfections that are not specifically calculated; exceeding the allowable values is not considered to be good practice (i.e. is not "safe |
https://en.wikipedia.org/wiki/Spring%20system | In engineering and physics, a spring system or spring network is a model of physics described as a graph with a position at each vertex and a spring of given stiffness and length along each edge. This generalizes Hooke's law to higher dimensions. This simple model can be used to solve the pose of static systems from crystal lattice to springs. A spring system can be thought of as the simplest case of the finite element method for solving problems in statics. Assuming linear springs and small deformation (or restricting to one-dimensional motion) a spring system can be cast as a (possibly overdetermined) system of linear equations or equivalently as an energy minimization problem.
Known spring lengths
If the nominal lengths, L, of the springs are known to be 1 and 2 units respectively, then the system can be solved as follows:
Consider the simple case of three nodes connected by two springs. Then the stretching of the two springs is given as a function of the positions of the nodes by
where is the matrix transpose of the incidence matrix
relating each degree of freedom to the direction each spring pulls on it.
The forces on the springs are
where W is a diagonal matrix giving the stiffness of every spring. Then the force on the nodes is given by left multiplying by , which we set to zero to find equilibrium:
which gives the linear equation:
.
Now, the matrix is singular, because all solutions are equivalent up to rigid-body translation. Let us prescribe a Dirichlet boundary condition, e.g., .
As an example, let W be the identity matrix then
is the Laplacian matrix. Plugging in we have
.
Incorporating the 2 to the left-hand side gives
.
and removing rows of the system that we already know, and simplifying, leaves us with
.
.
so we can then solve
.
That is, , as prescribed, and , leaving the first spring slack, and , leaving the second spring slack.
See also
Gaussian network model
Anisotropic Network Model
Stiffness matrix
Spring-mass system
Lapl |
https://en.wikipedia.org/wiki/Mathematics%20education%20in%20the%20United%20Kingdom | Mathematics education in the United Kingdom is largely carried out at ages 5–16 at primary school and secondary school (basic numeracy is taught at an earlier age in the Early Years).
Voluntary mathematics education in the UK takes place from 16 to 18, in sixth forms and other forms of further education. Whilst adults can study the subject at universities and higher education more widely. Mathematics education is not taught uniformly as exams and the syllabus vary across the countries of the United Kingdom, notably Scotland.
The Programme for International Student Assessment coordinated by the OECD currently ranks the knowledge and skills of British 15-year-olds in mathematics and science above OECD averages. In 2011, the Trends in International Mathematics and Science Study (TIMSS) rated 13–14-year-old pupils in England and Wales 10th in the world for maths and 9th for science.
History
The School Certificate was established in 1918, for education up to 16, with the Higher School Certificate for education up to 18; these were both established by the Secondary Schools Examinations Council (SSEC), which had been established in 1917.
1950s
The Association of Teachers of Mathematics was founded in 1950.
1960s
The Joint Mathematical Council was formed in 1963 to improve the teaching of mathematics in UK schools. The Ministry of Education had been created in 1944, which became the Department of Education and Science in 1964. The Schools Council was formed in 1964, which regulated the syllabus of exams in the UK, and existed until 1984. The exam body Mathematics in Education and Industry in Trowbridge was formed in 1963, formed by the Mathematical Association; the first exam Additional Mathematics was first set in 1965. The Institute of Mathematics and its Applications was formed in 1964, and is the UK's chartered body for mathematicians, being based in Essex.
Before calculators, many calculations would be done by hand with slide rules and log tables.
1970s
Decimal |
https://en.wikipedia.org/wiki/Overturning%20in%20the%20Subpolar%20North%20Atlantic%20Program | The Overturning in the Subpolar North Atlantic Program (OSNAP) is an international project designed to study the mechanistic link between water mass transformation at high latitudes and the meridional overturning circulation in the North Atlantic (AMOC) on interannual time scales. Though this linkage is evident in climate models on decadal time scales, to date there has been no clear demonstration of AMOC variability in response to changes in deep water formation on interannual and decadal time scales. OSNAP intends to fill that gap by providing a continuous record of the trans-basin fluxes of heat, mass and freshwater for a comparison to records of convective activity and water mass transformation at high latitudes in the North Atlantic.
The OSNAP observing system, fully deployed in the summer of 2014, consists of moorings, gliders and RAFOS floats spanning the subpolar North Atlantic from Labrador to Greenland to Scotland. Measurement contributions come from the US, the UK, Germany, the Netherlands, Canada, China and France. Vigorous boundary currents crossing the OSNAP line are directly measured in the Labrador and Irminger Seas by current meter arrays, and over the eastern flank of the Reykjanes Ridge by deep arrays. Geostrophic currents in the basin interior are estimated using temperature and salinity measurements from moorings and gliders. The AMOC is calculated on the basis of the directly measured boundary currents, the geostrophic currents and the Ekman transports estimated from the surface wind stress.
In conjunction with the RAPID/MOCHA array at 26⁰N, the EU THOR/NACLIM program and other observational elements, OSNAP will provide a comprehensive measure of the three-dimensional AMOC in the North Atlantic and an understanding of what drives its variability. The first OSNAP data products are expected in the fall of 2017.
See also
Thermohaline circulation
RAPID/MOCHA Array Rapid Climate Change-Meridional Overturning Circulation and Heatflux Arra |
https://en.wikipedia.org/wiki/Matryoshka%20doll | Matryoshka dolls ( ; ), also known as stacking dolls, nesting dolls, Russian tea dolls, or Russian dolls, are a set of wooden dolls of decreasing size placed one inside another. The name matryoshka, mainly known as "little matron", is a diminutive form of Matryosha (), in turn a diminutive of the Russian female first name Matryona ().
A set of matryoshkas consists of a wooden figure, which separates at the middle, top from bottom, to reveal a smaller figure of the same sort inside, which has, in turn, another figure inside of it, and so on.
The first Russian nested doll set was made in 1890 by wood turning craftsman and wood carver Vasily Zvyozdochkin from a design by Sergey Malyutin, who was a folk crafts painter at Abramtsevo. Traditionally the outer layer is a woman, dressed in a sarafan, a long and shapeless traditional Russian peasant jumper dress. The figures inside may be of any gender; the smallest, innermost doll is typically a baby turned from a single piece of wood. Much of the artistry is in the painting of each doll, which can be very elaborate. The dolls often follow a theme; the themes may vary, from fairy tale characters to Soviet leaders. In some countries, matryoshka dolls are often referred to as babushka dolls, though they are not known by this name in Russian; babushka () means "grandmother" or "old woman".
History
The first Russian nested doll set was carved in 1890 at the Children's Education Workshop by Vasily Zvyozdochkin and designed by Sergey Malyutin, who was a folk crafts painter in the Abramtsevo estate of Savva Mamontov, a Russian industrialist and patron of arts. Mamontov's brother, Anatoly Ivanovich Mamontov (1839–1905), created the Children's Education Workshop to make and sell children's toys. The doll set was painted by Malyutin. Malyutin's doll set consisted of eight dolls—the outermost was a mother in a traditional dress holding a red-combed rooster. The inner dolls were her children, girls and a boy, and the innermost a ba |
https://en.wikipedia.org/wiki/Superperfect%20number | In number theory, a superperfect number is a positive integer that satisfies
where is the divisor summatory function. Superperfect numbers are not a generalization of perfect numbers, but have a common generalization. The term was coined by D. Suryanarayana (1969).
The first few superperfect numbers are :
2, 4, 16, 64, 4096, 65536, 262144, 1073741824, ... .
To illustrate: it can be seen that 16 is a superperfect number as , and , thus .
If is an even superperfect number, then must be a power of 2, , such that is a Mersenne prime.
It is not known whether there are any odd superperfect numbers. An odd superperfect number would have to be a square number such that either or is divisible by at least three distinct primes. There are no odd superperfect numbers below 7.
Generalizations
Perfect and superperfect numbers are examples of the wider class of m-superperfect numbers, which satisfy
corresponding to m=1 and 2 respectively. For m ≥ 3 there are no even m-superperfect numbers.
The m-superperfect numbers are in turn examples of (m,k)-perfect numbers which satisfy
With this notation, perfect numbers are (1,2)-perfect, multiperfect numbers are (1,k)-perfect, superperfect numbers are (2,2)-perfect and m-superperfect numbers are (m,2)-perfect. Examples of classes of (m,k)-perfect numbers are:
{| class="wikitable"
|-
! m
! k
! (m,k)-perfect numbers
! OEIS sequence
|-
| 2
| 2
| 2, 4, 16, 64, 4096, 65536, 262144
|
|-
| 2
| 3
| 8, 21, 512
|
|-
| 2
| 4
| 15, 1023, 29127
|
|-
| 2
| 6
| 42, 84, 160, 336, 1344, 86016, 550095, 1376256, 5505024
|
|-
| 2
| 7
| 24, 1536, 47360, 343976
|
|-
| 2
| 8
| 60, 240, 960, 4092, 16368, 58254, 61440, 65472, 116508, 466032, 710400, 983040, 1864128, 3932160, 4190208, 67043328, 119304192, 268173312, 1908867072
|
|-
| 2
| 9
| 168, 10752, 331520, 691200, 1556480, 1612800, 106151936
|
|-
| 2
| 10
| 480, 504, 13824, 32256, 32736, 1980342, 1396617984, 3258775296
|
|-
| 2
| 11
| 4404480, 57669920, 238608384
|
|-
| 2
| 12
|
https://en.wikipedia.org/wiki/Fabric%20OS | In storage area networking, Fabric OS is the firmware for Brocade Communications Systems's Fibre Channel switches and Fibre Channel directors. It is also known as FOS.
First generation
The first generation of Fabric OS was developed on top of a VxWorks kernel and was mainly used in the Brocade Silkworm 2000 and first 3000 series on Intel i960. Even today, many production environments are still running the older generation Silkworm models.
Second generation
The second generation of Fabric OS was developed on a PowerPC platform, and uses MontaVista Linux, a Linux derivative with real-time performance enhancements. With the advent of MontaVista, switches and directors have the ability of hot firmware activation (without downtime for Fibre Channel fabric), and many useful diagnostic commands.
According to free software licenses terms, Brocade provides access to sources of distributed free software, on which Fabric OS and other Brocade's software products are based.
Additional licensed products
Additional products for Fabric OS are offered by Brocade for one-time fee. They are licensed for use in a single specific switch (license key is coupled with device's serial number). Those include:
Integrated Routing
Adaptive Networking: Quality of service, Ingress Rate Limiting
Brocade Advanced Zoning (Free with rel 6.1.x)
ISL trunking
Ports on Demand
Extended Fabrics (more than 10 km of switched fabric connectivity, up to 3000 km)
Advanced Performance Monitoring (APM)
Fabric Watch
Secure Fabric OS (obsolete)
VMWare VSPEX integration
Versions
Fabric OS 9.x
9.2:
9.1: Root Access Removal, NTP Server authentication
9.0: Traffic optimizer, Fabric congestion notification, New Web Tools (graphical UI switched from Java to Web)
Fabric OS 8.x
8.2: NVMe capable + REST API
8.1:
8.0: Contains many new software features and enhancements as well as issue resolutions
Fabric OS 7.x
7.4: Switch to Linux 3.10 kernel
7.3:
7.2:
7.1:
7.0:
Fabric OS 6.x
6.4:
6.3: Fill |
https://en.wikipedia.org/wiki/Mary%20Elizabeth%20Hickox%20Mandels | Mary Elizabeth Hickox Mandels (September 12, 1917 – February 17, 2008) was an American scientist. Mandels was an early advocate for converting waste biomass to fuels and chemicals. She worked for forty years at the head of the US Army's national bioconversion studies.
Early life
Mary Elizabeth Hickox was born to Sherman Gray and Mary Bolger Hickox in Middletown Springs, Vermont. Her family moved to Waterbury, Connecticut, where she lived with her parents and four siblings during the Great Depression.
Education
Hickox was accepted to study at Cornell University in 1939, but her father had to be persuaded by her science teacher that she should attend. Fully behind her after his initial doubts, he insisted that she complete her education after the death of her mother, rather than return home to care for her siblings.
Hickox' university career was interrupted by World War II and she completed her studies in 1947. Whilst at Cornell, she met and married Gabriel Mandels, becoming Mary Elizabeth Hickox Mandels.
Career
In 1955, Mandels began her research at the US Army Natick Laboratories. Mandel played a key role in clarifying the numerous components of the cellulase enzyme complex in moulds that had the ability to break down crystalline cellulose.
Mandels moved to the Food Science Laboratory in 1962, where she researched food production in "hostile" environments such as battlefields, Antarctica, or even space. Possibilities included single cell protein fermenter products and cellulolytic microbes.
In 1971 Mandels moved to the Bioengineering, Science and Advanced Technology Laboratory, and when Elwyn Reese retired in 1972 she became the head of this group.
In the early 1970s the oil crisis prompted Mandels and her team to focus their research upon the possibilities of using cellulose as an energy resource. It was essential to be able to measure cellulase activity, and Mandels developed an assay to predict the quantity of enzyme required. Subsequently, her paper 'Meas |
https://en.wikipedia.org/wiki/Zoo%20blot | A zoo blot or garden blot is a type of Southern blot that demonstrates the similarity between specific, usually protein-coding, DNA sequences of different species. A zoo blot compares animal species while a garden blot compares plant species. The purpose of the zoo blot is to detect the conservation of the gene(s) of interest throughout the evolution of different species.
In order to understand the degree to which a particular gene is similar from species to species, DNA extracts from a set of species are isolated and spread over a surface. Then, a gene probe specific to one of the species is labeled and allowed to hybridize to the prepared DNA. Usually, the probe is marked with a radioactive isotope of phosphorus. Following the hybridization, autoradiography or other imaging techniques are used to identify successfully hybridized probes, proof of similarity between species' genomes.
The hybridization between a probe and a segment of DNA will happen even when the strands are similar but not identical. As a result, zoo blotting is used to detect similar or exact relationships between the DNA in question and other organisms. It can also help establish the locations of introns and exons, as the latter will be far more conserved than the former.
See also
Southern blot
Fluorescent in situ hybridization |
https://en.wikipedia.org/wiki/Leccinum%20aurantiacum | Leccinum aurantiacum is a species of fungus in the genus Leccinum found in forests of Eurasia and North America. It has a large, characteristically red-capped fruiting body. In North America, it is sometimes referred to by the common name red-capped scaber stalk. Some uncertainties exist regarding the taxonomic classification of this species in Europe and North America. It is considered edible, but must be cooked thoroughly.
Description
The cap is orange-red and measures across. Its flesh is white, bruising at first burgundy, then grayish or purple-black. The underside of the cap has very small, whitish pores that bruise olive-brown. The stem measures tall and thick and can bruise blue-green. It is whitish, with short, rigid projections or scabers that turn to brown to black with age.
Distribution and habitat
L. aurantiacum can be found fruiting during summer and autumn in forests throughout Europe and North America. The association between fungus and host tree is mycorrhizal. In Europe, it has traditionally been associated with poplar trees. Some debate exists about the classification of L. aurantiacum and L. quercinum as separate species. According to authors who do not recognise the distinction, L. aurantiacum is also found among oak trees. Additionally, L. aurantiacum has been recorded with various other deciduous trees, including beech, birch, chestnut, willow, and trees of the genus Tilia. L. aurantiacum is not known to associate with conifers in Europe.
North American populations have been recorded in coniferous and deciduous forests, though whether collections from coniferous forests are not L. vulpinum, instead, remains uncertain. In addition, L. aurantiacum may be absent altogether from North America, with collections from deciduous forests being attributed to other North American species L. insigne, and L. brunneum.
Edibility
This is a favorite species for eating and can be prepared as other edible boletes. Its flesh turns very dark on cooking. Li |
https://en.wikipedia.org/wiki/Kuratowski%27s%20free%20set%20theorem | Kuratowski's free set theorem, named after Kazimierz Kuratowski, is a result of set theory, an area of mathematics. It is a result which has been largely forgotten for almost 50 years, but has been applied recently in solving several lattice theory problems, such as the congruence lattice problem.
Denote by the set of all finite subsets of a set . Likewise, for a positive integer , denote by the set of all -elements subsets of . For a mapping , we say that a subset of is free (with respect to ), if for any -element subset of and any , . Kuratowski published in 1951 the following result, which characterizes the infinite cardinals of the form .
The theorem states the following. Let be a positive integer and let be a set. Then the cardinality of is greater than or equal to if and only if for every mapping from to ,
there exists an -element free subset of with respect to .
For , Kuratowski's free set theorem is superseded by Hajnal's set mapping theorem. |
https://en.wikipedia.org/wiki/Stringed%20instrument%20tunings | This is a chart of stringed instrument tunings. Instruments are listed alphabetically by their most commonly known name.
Terminology
A course may consist of one or more strings.
Courses are listed reading from left to right facing the front of the instrument, with the instrument standing vertically. On a majority of instruments, this places the notes from low to high pitch.
Exceptions exist:
Instruments using reentrant tuning (e.g., the charango) may have a high string before a low string.
Instruments strung in the reverse direction (e.g. mountain dulcimer) will be noted with the highest sounding courses on the left and the lowest to the right.
A few instruments exist in "right-hand" and "left-hand" versions; left-handed instruments are not included here as separate entries, as their tuning is identical to the right-hand version, but with the strings in reverse order (e.g., a left-handed guitar).
Strings within a course are also given from left to right, facing the front of the instrument, with it standing vertically. Single-string courses are separated by spaces; multiple-string courses (i.e. paired or tripled strings) are shown with courses separated by bullet characters (•).
Pitch: Unless otherwise noted, contemporary western standard pitch (A4 = 440 Hz) and 12-tone equal temperament are assumed.
Octaves are given in scientific pitch notation, with Middle C written as "C4". (The 'A' above Middle C would then be written as "A4"; the next higher octave begins on "C5"; the next lower octave on "C3"; etc.)
Because stringed instruments are easily re-tuned, the concept of a "standard tuning" is somewhat flexible. Some instruments:
have a designated standard tuning (e.g., violin; guitar)
have more than one tuning considered "standard" (e.g. mejorana, ukulele)
do not have a standard tuning but rather a "common" tuning that is used more frequently than others (e.g., banjo; lap steel guitar)
are typically re-tuned to suit the music being played or the voice |
https://en.wikipedia.org/wiki/Pancreatic%20bud | The ventral and dorsal pancreatic buds (or pancreatic diverticula) are outgrowths of the duodenum during human embryogenesis. They join to form the adult pancreas.
The proximal portion of the dorsal pancreatic bud gives rise to the accessory pancreatic duct, while the distal portion of the dorsal pancreatic bud and ventral pancreatic bud give rise to the major pancreatic duct.
The ventral pancreatic bud develops into the pancreatic head and uncinate process.
Associated Disorders
In pancreas divisum the ducts of the pancreas are not fused to form a full pancreas, but instead it remains as a distinct dorsal and ventral duct. Without the proper fusion of both ducts the majority of the pancreas drainage is mainly through the accessory papilla. Three different variations in pancreas divisum have been described: the first is the classic example of pancreas divisum in which the ventral duct is visualized but there is total failure of fusion; the second variation is with the absence of a ventral duct; and the third variation is when there is very basic communication between the two ducts. Pancreatitis is a major complication of pancreas divisum.
Additional images |
https://en.wikipedia.org/wiki/Desuspension | In topology, a field within mathematics, desuspension is an operation inverse to suspension.
Definition
In general, given an n-dimensional space , the suspension has dimension n + 1. Thus, the operation of suspension creates a way of moving up in dimension. In the 1950s, to define a way of moving down, mathematicians introduced an inverse operation , called desuspension. Therefore, given an n-dimensional space , the desuspension has dimension n – 1.
In general, .
Reasons
The reasons to introduce desuspension:
Desuspension makes the category of spaces a triangulated category.
If arbitrary coproducts were allowed, desuspension would result in all cohomology functors being representable.
See also
Cone (topology)
Equidimensionality
Join (topology) |
https://en.wikipedia.org/wiki/Binomial%20sum%20variance%20inequality | The binomial sum variance inequality states that the variance of the sum of binomially distributed random variables will always be less than or equal to the variance of a binomial variable with the same n and p parameters. In probability theory and statistics, the sum of independent binomial random variables is itself a binomial random variable if all the component variables share the same success probability. If success probabilities differ, the probability distribution of the sum is not binomial. The lack of uniformity in success probabilities across independent trials leads to a smaller variance. and is a special case of a more general theorem involving the expected value of convex functions. In some statistical applications, the standard binomial variance estimator can be used even if the component probabilities differ, though with a variance estimate that has an upward bias.
Inequality statement
Consider the sum, Z, of two independent binomial random variables, X ~ B(m0, p0) and Y ~ B(m1, p1), where Z = X + Y. Then, the variance of Z is less than or equal to its variance under the assumption that p0 = p1, that is, if Z had a binomial distribution. Symbolically, .
We wish to prove that
We will prove this inequality by finding an expression for Var(Z) and substituting it on the left-hand side, then showing that the inequality always holds.
If Z has a binomial distribution with parameters n and p, then the expected value of Z is given by E[Z] = np and the variance of Z is given by Var[Z] = np(1 – p). Letting n = m0 + m1 and substituting E[Z] for np gives
The random variables X and Y are independent, so the variance of the sum is equal to the sum of the variances, that is
In order to prove the theorem, it is therefore sufficient to prove that
Substituting E[X] + E[Y] for E[Z] gives
Multiplying out the brackets and subtracting E[X] + E[Y] from both sides yields
Multiplying out the brackets yields
Subtracting E[X] and E[Y] from both sides and reversing |
https://en.wikipedia.org/wiki/Subscapularis%20muscle | The subscapularis is a large triangular muscle which fills the subscapular fossa and inserts into the lesser tubercle of the humerus and the front of the capsule of the shoulder-joint.
Structure
The subscapularis is covered by a dense fascia which attaches to the scapula at the margins of the subscapularis' attachment (origin) on the scapula.
The muscle's fibers pass laterally from its origin before coalescing into a tendon of insertion. The tendon intermingles with the glenohumeral (shoulder) joint capsule.
A bursa (which communicates with the cavity of the shoulder joint via an aperture in the joint capsule) intervenes between the tendon and a bare area at the lateral angle of the scapula/the neck of the scapula. The subscapularis (supraserratus) bursa separates the subscapularis is from the serratus anterior.
Origin
It arises from its medial two-thirds of the costal surface of the scapula, the intermuscular septa (which create ridges upon the scapula), and the lower two-thirds of the groove on the axillary border (subscapular fossa) of the scapula.
Some fibers arise from tendinous laminae, which intersect the muscle and are attached to ridges on the bone; others from an aponeurosis, which separates the muscle from the teres major and the long head of the triceps brachii.
Insertion
It inserts onto the lesser tubercle of the humerus and the anterior part of the shoulder-joint capsule. Tendinous fibers extend to the greater tubercle with insertions into the bicipital groove.
Innervation
The subscapularis is supplied by the upper and lower subscapular nerves (C5-C6), branches of the posterior cord of the brachial plexus.
Actions/movements
The subscapularis medially (internally) rotates the humerus (acting here as a prime mover) and adducts it. When the arm is raised, it draws the humerus forward and downward.
Function
The subscapularis stabilises the shoulder joint by contributing to the fixation of the proximal humerus during movements of the elbow, wr |
https://en.wikipedia.org/wiki/Pyrenocine | Pyrenocines are antibiotic mycotoxins.
Chemical structures |
https://en.wikipedia.org/wiki/Language%20Integrated%20Query | Language Integrated Query (LINQ, pronounced "link") is a Microsoft .NET Framework component that adds native data querying capabilities to .NET languages, originally released as a major part of .NET Framework 3.5 in 2007.
LINQ extends the language by the addition of query expressions, which are akin to SQL statements, and can be used to conveniently extract and process data from arrays, enumerable classes, XML documents, relational databases, and third-party data sources. Other uses, which utilize query expressions as a general framework for readably composing arbitrary computations, include the construction of event handlers or monadic parsers. It also defines a set of method names (called standard query operators, or standard sequence operators), along with translation rules used by the compiler to translate query syntax expressions into expressions using fluent-style (called method syntax by Microsoft) with these method names, lambda expressions and anonymous types.
Ports of LINQ exist for PHP (PHPLinq), JavaScript (linq.js), TypeScript (linq.ts), and ActionScript (ActionLinq), although none are strictly equivalent to LINQ in the .NET inspired languages C#, F# and VB.NET (where it is a part of the language, not an external library, and where it often addresses a wider range of needs).
Architecture of LINQ in the .NET Framework
Standard Query Operator API
In what follows, the descriptions of the operators are based on the application of working with collections. Many of the operators take other functions as arguments. These functions may be supplied in the form of a named method or anonymous function.
The set of query operators defined by LINQ is exposed to the user as the Standard Query Operator (SQO) API. The query operators supported by the API are:
Select
The Select operator performs a projection on the collection to select
interesting aspects of the elements. The user supplies an arbitrary function, in the form of a named or lambda expression, which p |
https://en.wikipedia.org/wiki/NWLink | NWLink is Microsoft's implementation of Novell's IPX/SPX protocols. NWLink includes an implementation of NetBIOS atop IPX/SPX.
NWLink packages data to be compatible with client/server services on NetWare Networks. However, NWLink does not provide access to NetWare File and Print Services. To access the File and Print Services the Client Service for NetWare needs to be installed.
NWLink connects NetWare servers through the Gateway Service for NetWare or Client Service for NetWare and provides the transport protocol that connects Windows operating systems to IPX/SPX NetWare networks and compatible operating systems. NWLink supports NetBIOS and Windows Sockets application programming interfaces (API).
NWLink protocols are as follows:
SPX/SPXII
IPX
Service Advertising Protocol (SAP)
Routing Information Protocol (RIP)
NetBIOS
Forwarder
NWLink also provides the following functionalities:
Runs other communication protocol stacks, such as Transmission Control Protocol/Internet Protocol (TCP/IP)
Uses multiple frame types for network adapter binding
Using NWLink IPX/SPX/NetBIOS
NWLink IPX/SPX/NetBIOS Compatible Transport is Microsoft's implementation of the Novell IPX/SPX (Internetwork Packet Exchange/Sequenced Packet Exchange) protocol stack. The Windows XP implementation of the IPX/SPX protocol stack adds NetBIOS support.
The main function of NWLink is to act as a transport protocol to route packets through internetworks. By itself, the NWLink protocol does not allow you to access the data across the network. If you want to access NetWare File and Print Services, you must install NWLink and Client Services for NetWare (software that works at the upper layers of the OSI model to allow access to file and print services).
One advantage of using NWLink is that is easy to install and configure.
Configuring NWLink IPX/SPX
The only options that are configured for NWLink are the internal network number and the frame type. Normally, you leave both settings at their |
https://en.wikipedia.org/wiki/Outline%20of%20web%20design%20and%20web%20development | The following outline is provided as an overview of and topical guide to web design and web development, two very related fields:
Web design – field that encompasses many different skills and disciplines in the production and maintenance of websites. The different areas of web design include web graphic design; interface design; authoring, including standardized code and proprietary software; user experience design; and search engine optimization. Often many individuals will work in teams covering different aspects of the design process, although some designers will cover them all. The term web design is normally used to describe the design process relating to the front-end (client side) design of a website including writing markup. Web design partially overlaps web engineering in the broader scope of web development. Web designers are expected to have an awareness of usability and if their role involves creating markup then they are also expected to be up to date with web accessibility guidelines.
Web development – work involved in developing a web site for the Internet (World Wide Web) or an intranet (a private network). Web development can range from developing a simple single static page of plain text to complex web-based internet applications (web apps), electronic businesses, and social network services. A more comprehensive list of tasks to which web development commonly refers, may include web engineering, web design, web content development, client liaison, client-side/server-side scripting, web server and network security configuration, and e-commerce development.
Among web professionals, "web development" usually refers to the main non-design aspects of building web sites: writing markup and coding. Web development may use content management systems (CMS) to make content changes easier and available with basic technical skills.
For larger organizations and businesses, web development teams can consist of hundreds of people (web developers) and follow |
https://en.wikipedia.org/wiki/Einstein%E2%80%93Hopf%20drag | In physics, the Einstein–Hopf drag (named after Albert Einstein and Ludwig Hopf) is a velocity-dependent drag force upon charged particles that are being bathed in thermal radiation. |
https://en.wikipedia.org/wiki/POTS%20codec | A POTS codec is a type of audio coder-decoder (codec) that uses digital signal processing to transmit audio digitally over standard telephone lines (plain old telephone service, POTS) at a higher level of audio quality than the telephone line would normally provide in its analog mode. The POTS codec is one of a family of broadcast codecs differentiated by the type of telecommunications circuit used for transmission. The ISDN codec, which instead uses ISDN lines, and the IP codec which uses private or public IP networks are also common.
Primarily used in broadcast engineering to link remote broadcast locations to the host studio, a hardware codec, implemented with digital signal processing, is used to compress the audio data enough to travel through a pair of a 33.6k modems.
POTS codecs have the disadvantages of being restricted to relatively low bit rates and being susceptible to variable line quality. ISDN and IP codecs have the advantage of being natively digital, and operate at much higher bitrates, which results in fewer compression artifacts. Special lines must be run to a location, however, and must be ordered well in advance of the event so that there is ample time for installation of equipment. Since POTS lines are almost universally available, the POTS codec can be set up nearly anywhere with little or no notice.
Uses
The main use of a broadcast codec is for remote broadcasting by radio stations.
Functions
Codecs usually come in two types of units: rackmount for the studio and portable for the remote. Audio can be sent in either direction, and most can also pass low-speed non-audio data, allowing the remote DJ to control broadcast automation or other studio equipment via RS-232. Many have an automatic redial if the line should become disconnected. The remote unit usually has some basic mixer functions, while the studio unit usually has some kind of digital output.
Some codecs can be configured to use ISDN, POTS or IP rather than requiring a differe |
https://en.wikipedia.org/wiki/Characterization%20of%20probability%20distributions | In mathematics in general, a characterization theorem says that a particular object – a function, a space, etc. – is the only one that possesses properties specified in the theorem. A characterization of a probability distribution accordingly states that it is the only probability distribution that satisfies specified conditions. More precisely, the model of characterization of
probability distribution was described by in such manner. On the probability space we define the space of random variables with values in measurable metric space and the space of random variables with values in measurable metric space . By characterizations of probability distributions we understand general problems of description of some set in the space by extracting the sets and which describe the properties of random variables and their images , obtained by means of a specially chosen mapping .
The description of the properties of the random variables and of their images is equivalent to the indication of the set from which must be taken and of the set into which its image must fall. So, the set which interests us appears therefore in the following form:
where denotes the complete inverse image of in . This is the general model of characterization of probability distribution. Some examples of characterization theorems:
The assumption that two linear (or non-linear) statistics are identically distributed (or independent, or have a constancy regression and so on) can be used to characterize various populations. For example, according to George Pólya's characterization theorem, if and are independent identically distributed random variables with finite variance, then the statistics and are identically distributed if and only if and have a normal distribution with zero mean. In this case
,
is a set of random two-dimensional column-vectors with independent identically distributed components, is a set of random two-dimensional column-vectors with identically distr |
https://en.wikipedia.org/wiki/Deinococcus%20geothermalis | Deinococcus geothermalis is a non-pathogenic, sphere-shaped, Gram-positive, heterotrophic bacterium, where geothermalis means 'hot earth' or 'hot springs'. This bacterium was first obtained from the hot springs of Agnano, Naples, Italy and São Pedro do Sul, Portugal.
Genome Structure
Deinococcus geothermalis has a genome that contains 2.47 Mbp with 2,335 protein coding genes. There are 73 insertion sequences (IS) contained in the genome, with 19 different types of ISs'. Upon oxidative stress these ISs' are actively transposed in the bacterium. Additionally, it carries at least 2 plasmids.
Growth Characteristics
Deniococcus geothermalis form tetrads when dividing. The size of their cells range from 1.2 - 2.0μm in diameter. It produces orange-pigmented colonies and has an optimum growth temperature of about to , which is the limit between mesophile and thermophile organisms. As well as having a pH optimum of 6.5. Given all this, they are able to grow in environments where nutrients are limited, and can even use ammonium sulfate for biomass accumulation. It is extremely gamma radiation-resistant. Mn(II) concentrations are high in the cell. Fe(III)-nitrilotriacetic acid, U(V), and Cr(VI) can all be reduced by D. geothermalis, which has also been engineered to reduce Hg(II) as well, from a plasmid originally constructed for Deinococcus radiodurans. Its type strain is AG-3a (= DSM 11300).
Biofilm Formation
It is able to form thick biofilms on non-living surfaces, such as printing machines, glass, stainless steel, polystyrenes, polyethylene, etc., which are characterized by adhesion threads and lack of a slime matrix. Biofilms were visualized with high resolution field-emission scanning electron microscopy and atomic force microscopy (AMF). In particular, Deniococcus geothermalis biofilms on printing equipment can help other bacteria form biofilms on top of the existing one, referred to as a secondary biofilm bacterium. Their biofilms are tightly adhered to surface |
https://en.wikipedia.org/wiki/Shenzhen%20I/O | Shenzhen I/O is a puzzle video game and programming game developed by Zachtronics for Microsoft Windows, Linux, and macOS-based personal computers. The game was released in November 2016.
Gameplay
Shenzhen I/O is a puzzle video game set in the near future in which players assume the role of an electronics engineer who has emigrated to Shenzhen, China to work for fictional technology company Shenzhen Longteng Electronics. The player is tasked with creating products for clients, which involves constructing circuits and then writing code to run them. The programming language used in the game is similar to assembly language and the circuit elements resemble simplified versions of real-world electronics.
The game allows players to create their own challenges by writing Lua scripts.
Development and release
Shenzhen I/O was developed by Zachtronics. The game is seen as a spiritual successor to their previous title TIS-100, a coding puzzle game released in 2015. Shenzhen I/O was designed with the same niche audience in mind, specifically people interested in programming. The idea of using the city of Shenzhen, which is a major electronics and high technology manufacturing center in China, as the setting came from Barth reading blogs from Andrew "bunnie" Huang about his experiences there.
The game features a more approachable user interface than TIS-100 and a cast of characters. Zachtronics was reluctant to include a tutorial to teach players how to play Shenzhen I/O. Instead they opted to include a dense manual containing helpful information. Narrative elements are woven into the manual and gameplay by tasking the player to create fictional products.
Zachtronics announced Shenzhen I/O in September 2016, and released an in-development version of the game via Steam Early Access in October 2016. The game launched out of early access for Linux, macOS, and Windows on November 17, 2016. The release was at the conclusion of about six months of development work.
From players' |
https://en.wikipedia.org/wiki/Vertebrate%20Genomes%20Project | The Vertebrate Genomes Project (VGP) is a project which aims to generate high-quality, complete reference genomes of all 66,000 vertebrate species. It is an international cooperation project with members from more than 50 separate institutions and was launched in February 2017.
In October 2021, VGP partnered with Colossal Biosciences to sequence and assemble elephant genomes for preservation purposes.
In April 2022, VGP partnered with the Human Genome Project and the African BioGenome Project for sequencing research.
In July 2022, VGP and Colossal Biosciences announced that they successfully sequenced the entire Asian elephant genome; this is the first time that mammalian genetic code has been fully sequenced to this degree since the Human Genome Project was completed in the early 2000s.
In November 2022, VGP successfully sequenced the Nile Rat genome in order to facilitate research on type 2 diabetes and the health effects of circadian rhythm disruption. Not only did researchers sequence an individual rat, but they also sequenced both its parents, allowing them to separate the original rat’s alleles by parental haplotype. The resulting sequence showed that the vast majority of expected protein-coding genes were accounted for. |
https://en.wikipedia.org/wiki/Glycobiology%20%28journal%29 | Glycobiology is a monthly peer-reviewed scientific journal covering all aspects of the field of glycobiology and the official journal of the Society for Glycobiology. It is published by Oxford University Press. The journal was established in September 1990. It publishes primary research on the "biological functions of glycans, including glycoproteins, glycolipids, proteoglycans and free oligosaccharides, and on proteins that specifically interact with glycans."
Abstracting and indexing
The journal is indexed in Index Medicus/PubMed/MEDLINE, Index Veterinarius, CAB Abstracts, Biological Abstracts, BIOSIS Previews, Current Contents/Life Sciences, ProQuest, Science Citation Index, and others. According to the Journal Citation Reports, its 2019 impact factor is 4.060, ranking it 102nd out of 297 journals in the category "Biochemistry & Molecular Biology". |
https://en.wikipedia.org/wiki/Shelter%202 | Shelter 2 is an open world survival video game developed by Might and Delight for Windows, Mac OS X, and Linux. The game is a sequel to 2013's Shelter. It was released on March 9, 2015 and, like its predecessor, was made available on Steam as a digital download.
Gameplay
In Shelter 2 the player controls a mother lynx, looking after her kittens by keeping them fed and safe from danger. The game aimed to contain new types of movement compared to the original, a bigger variety of prey, and a larger open world which changes during the four seasons. Additional instructions are available to the player such as instructing the cubs to drink from a river. The player must make sure the cubs are safely back in the family's den at night time and the seasons affect what food and water is available.
The game starts with the mother lynx pregnant and preparing a den. The player is able to name each of the kittens, and those which survive a playthrough are playable as the next generation of the family tree.
Development
In March 2014 Might and Delight announced the development of Shelter 2, releasing a teaser trailer and setting a release date of Autumn 2014. The game was delayed to March 9, 2015 in October 2014 after the developers announced a different game would be released first, The Blue Flamingo.
Reception
GameSpot awarded Shelter 2 a score of 6 out of 10, saying that it "has the right spirit, the right ideas, and it is once again hamstrung by its inability to go the extra, needed mile to do them justice". Destructoid was more critical, awarding it 3 out of 10 and saying "something went wrong somewhere along the line."
Expansions
Shelter 2: Mountains was released on 25 August 2015. It adds a whole new area, with new dangers that you can turn off in the main menu. New dangers include the fox, eagle, forest fire, and bear. The mountains are located north of the den area. |
https://en.wikipedia.org/wiki/Contraction%20band%20necrosis | Contraction band necrosis is a type of uncontrolled cell death (necrosis) unique to cardiac myocytes and thought to arise in reperfusion from hypercontraction, which results in sarcolemmal rupture.
It is a characteristic histologic finding of a recent myocardial infarction (heart attack) that was partially reperfused.
The name of the histopathologic finding comes from the appearance under the microscope; contraction bands are thick intensely eosinophilic staining bands (typically 4-5 micrometres wide) that span the short axis of the myocyte. They can be thought of extra thick striae, typical of cardiac muscle and striated muscle.
Pathophysiology
Contraction band necrosis is thought to arise by two mechanisms:
a calcium-dependent mechanism - activation of the contractile machinery of the cell via its usual mechanism, calcium, which is in excess due to ischemia.
a calcium-independent mechanism, as seen in rigor mortis - activation of the contractile machinery in the setting of low ATP.
Reperfusion associated cell death has been modulated (reduced) in animal studies and is an area of active research, which holds the potential to significantly reduce the morbidity and mortality of cardiovascular disease.
Additional images
See also
Myocardial infarction
Timeline of myocardial infarction pathology
Guanylyl cyclase |
https://en.wikipedia.org/wiki/Jeans%20instability | In stellar physics, the Jeans instability causes the collapse of interstellar gas clouds and subsequent star formation, named after James Jeans. It occurs when the internal gas pressure is not strong enough to prevent gravitational collapse of a region filled with matter. For stability, the cloud must be in hydrostatic equilibrium, which in case of a spherical cloud translates to
where is the enclosed mass, is the pressure, is the density of the gas (at radius ), is the gravitational constant, and is the radius. The equilibrium is stable if small perturbations are damped and unstable if they are amplified. In general, the cloud is unstable if it is either very massive at a given temperature or very cool at a given mass; under these circumstances, the gas pressure gradient cannot overcome gravitational force, and the cloud will collapse.
The Jeans instability likely determines when star formation occurs in molecular clouds.
Jeans mass
The Jeans mass is named after the British physicist Sir James Jeans, who considered the process of gravitational collapse within a gaseous cloud. He was able to show that, under appropriate conditions, a cloud, or part of one, would become unstable and begin to collapse when it lacked sufficient gaseous pressure support to balance the force of gravity. The cloud is stable for sufficiently small mass (at a given temperature and radius), but once this critical mass is exceeded, it will begin a process of runaway contraction until some other force can impede the collapse. He derived a formula for calculating this critical mass as a function of its density and temperature. The greater the mass of the cloud, the bigger its size, and the colder its temperature, the less stable it will be against gravitational collapse.
The approximate value of the Jeans mass may be derived through a simple physical argument. One begins with a spherical gaseous region of radius , mass , and with a gaseous sound speed . The gas is compressed slight |
https://en.wikipedia.org/wiki/Chain%20fern | Chain fern is a common name for several ferns and may refer to:
Woodwardia, a fern genus of the Northern Hemisphere
Tmesipteris, a fern genus of the South Pacific, also called "hanging fork fern"
Ferns |
https://en.wikipedia.org/wiki/Journal%20of%20Computational%20Biophysics%20and%20Chemistry | The Journal of Computational Biophysics and Chemistry is a peer-reviewed scientific journal covering developments in theoretical and computational chemistry and biophysics, as well as their applications to other scientific fields, such as medicine, pharmaceutical and materials sciences. It was established in 2002 as the Journal of Theoretical and Computational Chemistry, obtaining its current title in 2021. It is published by World Scientific and the editor-in-chief is Emil Alexov (Clemson University).
Abstracting and indexing
The journal is abstracted and indexed in:
Chemical Abstracts Service
Current Contents/Physical, Chemical & Earth Sciences
EBSCO databases
Inspec
ProQuest databases
Science Citation Index Expanded
Scopus
According to the Journal Citation Reports, the journal has a 2021 impact factor of 2.440. |
https://en.wikipedia.org/wiki/Nonclassical%20ion | Nonclassical carbocations are stabilized by charge delocalization from contributions of neighbouring or bonds, which can form bridged intermediates or transition states. Nonclassical ions have been extensively studied with the 2-norbornyl system, which as “naked” ion unambiguously exhibit such a bridged structure. The landmark of nonclassical ions are unexpectedly fast solvolysis rates and large differences between epimeric esters. Such behaviour is not restricted to 2-norbornyl esters, as has been shown with some cyclopentyl and steroidal esters with the tosyloxy leaving group.
Substitution reactions of secondary esters occur by SN2- or SN1-like mechanisms. Only in highly polar solvents such as hexafluoroisopropanol (HFIP) of low nucleophilicity one can expect a nearly same uniform SN1-like mechanism. The solvolysis of several cyclopentyl and steroidal esters show that large solvolysis rates and differences between epimers can occur which surpass those of the 2-norbornyl system. In these cases a vicinal C–C or C–H bond can lead to significant delocalization of the positive charge, if these bonds are close to antiperiplanar to the leaving group, and the migration leads to a more stable tertiary carbocation. The reaction products in these cases always result from the migration of the neighbouring bond.
The reaction of epimeric esters can be severely slowed by steric hindrance of solvation.
Solvolysis of cyclopropylcarbinyl, cyclobutyl and homoallyl esters are also characterized by very large rates, and have been shown to occur via a common nonclassical ion structure in the form of a bicyclobutonium ion.
See also
2-Norbornyl cation
Neighbouring group participation
Carbocation
Steric effects
Solvation |
https://en.wikipedia.org/wiki/Trophobiosis | Trophobiosis is a symbiotic association between organisms where food is obtained or provided. The provider of food in the association is referred to as a trophobiont. The name is derived from the Ancient Greek τροφή (trophē), meaning "nourishment", and -βίωσις (-biosis), which is short for the English word symbiosis.
Among the more noted trophobiotic groups are ants and members of a number of hemipteran families. A number of ant genera are recorded as tending groups of hemipterans to varying degrees. In most cases the ants collect and transport the honeydew secretions from the hemipterans back to the nest for consumption. Not all examples of ant trophobiotic interactions are mutualistic, with instances such as ants attracted to Cacopsylla pyricola feeding on both the honeydew and the C. pyricola individuals. This interaction has been recorded in Ancient Chinese writings and is noted as one of the oldest instances of biological pest control.
In mutualistic relationships, the production of honeydew by trophobionts is rewarded by removal of dead hemipterans and protection from a variety of predators by the attendant ants. In some relationships the ants will build shelters for the farmed trophobionts, either to protect them or keep them from leaving the area. Some species of ants construct underground rooms to house the trophobionts and carry them between the host plant and housing area daily. In more complex obligate relationships (where both symbionts entirely depend on each other for survival) the ants will nest with the partner trophobionts in silk constructed leaf shelters or in underground colonies. Several species of migratory ants are noted to bring the trophobiont species with them when they move, transporting the trophobionts to new feeding areas and acting as a quick escape method if danger arises. While aphids, mealybugs and other more sedentary hemipterans are most often used as trophobionts, occasional instances of more active hemipterans such as |
https://en.wikipedia.org/wiki/Lane%E2%80%93Emden%20equation | In astrophysics, the Lane–Emden equation is a dimensionless form of Poisson's equation for the gravitational potential of a Newtonian self-gravitating, spherically symmetric, polytropic fluid. It is named after astrophysicists Jonathan Homer Lane and Robert Emden. The equation reads
where is a dimensionless radius and is related to the density, and thus the pressure, by for central density . The index is the polytropic index that appears in the polytropic equation of state,
where and are the pressure and density, respectively, and is a constant of proportionality. The standard boundary conditions are and . Solutions thus describe the run of pressure and density with radius and are known as polytropes of index . If an isothermal fluid (polytropic index tends to infinity) is used instead of a polytropic fluid, one obtains the Emden–Chandrasekhar equation.
Applications
Physically, hydrostatic equilibrium connects the gradient of the potential, the density, and the gradient of the pressure, whereas Poisson's equation connects the potential with the density. Thus, if we have a further equation that dictates how the pressure and density vary with respect to one another, we can reach a solution. The particular choice of a polytropic gas as given above makes the mathematical statement of the problem particularly succinct and leads to the Lane–Emden equation. The equation is a useful approximation for self-gravitating spheres of plasma such as stars, but typically it is a rather limiting assumption.
Derivation
From hydrostatic equilibrium
Consider a self-gravitating, spherically symmetric fluid in hydrostatic equilibrium. Mass is conserved and thus described by the continuity equation
where is a function of . The equation of hydrostatic equilibrium is
where is also a function of . Differentiating again gives
where the continuity equation has been used to replace the mass gradient. Multiplying both sides by and collecting the derivatives of on the left, |
https://en.wikipedia.org/wiki/Matrix%20decomposition | In the mathematical discipline of linear algebra, a matrix decomposition or matrix factorization is a factorization of a matrix into a product of matrices. There are many different matrix decompositions; each finds use among a particular class of problems.
Example
In numerical analysis, different decompositions are used to implement efficient matrix algorithms.
For instance, when solving a system of linear equations , the matrix A can be decomposed via the LU decomposition. The LU decomposition factorizes a matrix into a lower triangular matrix L and an upper triangular matrix U. The systems and require fewer additions and multiplications to solve, compared with the original system , though one might require significantly more digits in inexact arithmetic such as floating point.
Similarly, the QR decomposition expresses A as QR with Q an orthogonal matrix and R an upper triangular matrix. The system Q(Rx) = b is solved by Rx = QTb = c, and the system Rx = c is solved by 'back substitution'. The number of additions and multiplications required is about twice that of using the LU solver, but no more digits are required in inexact arithmetic because the QR decomposition is numerically stable.
Decompositions related to solving systems of linear equations
LU decomposition
Traditionally applicable to: square matrix A, although rectangular matrices can be applicable.
Decomposition: , where L is lower triangular and U is upper triangular
Related: the LDU decomposition is , where L is lower triangular with ones on the diagonal, U is upper triangular with ones on the diagonal, and D is a diagonal matrix.
Related: the LUP decomposition is , where L is lower triangular, U is upper triangular, and P is a permutation matrix.
Existence: An LUP decomposition exists for any square matrix A. When P is an identity matrix, the LUP decomposition reduces to the LU decomposition.
Comments: The LUP and LU decompositions are useful in solving an n-by-n system of linear equations |
https://en.wikipedia.org/wiki/Application-Layer%20Protocol%20Negotiation | Application-Layer Protocol Negotiation (ALPN) is a Transport Layer Security (TLS) extension that allows the application layer to negotiate which protocol should be performed over a secure connection in a manner that avoids additional round trips and which is independent of the application-layer protocols. It is used to establish HTTP/2 connections without additional round trips (client and server can communicate over to ports previously assigned to HTTPS with HTTP/1.1 and upgrade to use HTTP/2 or continue with HTTP/1.1 without closing the initial connection).
Support
ALPN is supported by these libraries:
BSAFE Micro Edition Suite since version 5.0
GnuTLS since version 3.2.0 released in May 2013
MatrixSSL since version 3.7.1 released in December 2014
Network Security Services since version 3.15.5 released in April 2014
OpenSSL since version 1.0.2 released in January 2015
LibreSSL since version 2.1.3 released in January 2015
mbed TLS (previously PolarSSL) since version 1.3.6 released in April 2014
s2n since its original public release in June 2015.
wolfSSL (formerly CyaSSL) since version 3.7.0 released in October 2015
Go (in the standard library crypto/tls package) since version 1.4 released in December 2014
JSSE in Java since JDK 9 released in September 2017, backported to JDK 8 released in April 2020
Win32 SSPI since Windows 8.1 and Windows Server 2012 R2 were released October 18, 2013
History
Next Protocol Negotiation
In January 2010, Google introduced IETF standard draft describing Next Protocol Negotiation TLS extension. This extension was used to negotiate experimental SPDY connections between Google Chrome and some of Google's servers. As SPDY evolved, NPN was replaced with ALPN.
Application-Layer Protocol Negotiation
On July 11, 2014, ALPN was published as . ALPN replaces Next Protocol Negotiation (NPN) extension.
TLS False Start was disabled in Google Chrome from version 20 (2012) onward except for websites with the earlier NPN extension.
|
https://en.wikipedia.org/wiki/Rota%E2%80%93Baxter%20algebra | In mathematics, a Rota–Baxter algebra is an associative algebra, together with a particular linear map R which satisfies the Rota–Baxter identity. It appeared first in the work of the American mathematician Glen E. Baxter in the realm of probability theory. Baxter's work was further explored from different angles by Gian-Carlo Rota, Pierre Cartier, and Frederic V. Atkinson, among others. Baxter’s derivation of this identity that later bore his name emanated from some of the fundamental results of the famous probabilist Frank Spitzer in random walk theory.
In the 1980s, the Rota-Baxter operator of weight 0 in the context of Lie algebras was rediscovered as the operator form of the classical Yang–Baxter equation, named after the well-known physicists Chen-Ning Yang and Rodney Baxter.
The study of Rota–Baxter algebras experienced a renaissance this century, beginning with several developments, in the algebraic approach to renormalization of perturbative quantum field theory, dendriform algebras, associative analogue of the classical Yang–Baxter equation and mixable shuffle product constructions.
Definition and first properties
Let k be a commutative ring and let be given. A linear operator R on a k-algebra A is called a Rota–Baxter operator of weight if it satisfies the Rota–Baxter relation of weight :
for all . Then the pair or simply A is called a Rota–Baxter algebra of weight . In some literature, is used in which case the above equation becomes
called the Rota-Baxter equation of weight . The terms Baxter operator algebra and Baxter algebra are also used.
Let be a Rota–Baxter of weight . Then is also a Rota–Baxter operator of weight . Further, for in k, is a Rota-Baxter operator of weight .
Examples
Integration by parts
Integration by parts is an example of a Rota–Baxter algebra of weight 0. Let be the algebra of continuous functions from the real line to the real line. Let : be a continuous function. Define integration as the Rota–Baxter operato |
https://en.wikipedia.org/wiki/Discovery%20District | The Discovery District is one of the commercial districts in Downtown Toronto, Ontario, Canada. It has a high concentration of hospitals and research institutions, particularly those related to biotechnology. The district is roughly bounded by Bloor Street on the north, Bay Street on the east, Dundas Street on the south, and Spadina Avenue on the west.
Characteristics
The area includes the main campuses of the University of Toronto and Toronto Metropolitan University, as well as university affiliated health-care research hospitals including the Hospital for Sick Children, Toronto General Hospital, Princess Margaret Cancer Centre, Mount Sinai Hospital, Toronto Rehabilitation Institute Women's College Hospital, and the MaRS Discovery District. These institutions are concentrated near the intersection of University Avenue and College Streets but the District generally extends north to Bloor Street, south to Dundas Street, east to Bay Street and West to Spadina Avenue. A number of key organizations within the Ontario life sciences community are also located here including Ontario Genomics, Ontario Bioscience Innovation Organization (OBIO), Toronto Innovation Acceleration Partners (TIAP) and JLabs Toronto.
History: this area was subdivided from three main 'park lot' estates: Macaulay Estate (to the east, became a residential district known as 'the Ward' until demolished), Elmsley Estate (redivided with the Macaulay Estate which was concentrated to the south. Elmsley estate is closely tied with the history of both the University of Toronto and the commercial district on Yonge Street) and the Powell Estate (became the 'University Park' now the University of Toronto)
A short stretch of Gerrard Street West from Bay Street to LaPlante Avenue was referred to as Gerrard Village, a Bohemian Greenwich Village like area from the late 19th century to the early 1970s.
This area is referred to by Statistics Canada as census tract 5350035.00. According to the 2011 National Hous |
https://en.wikipedia.org/wiki/Flora%20von%20Th%C3%BCringen | Flora von Thüringen is an extensive botanical coverage of the plants occurring in Thuringia in central Germany. Conceived and initiated by the German naturalist Jonathan Carl Zenker in 1836, its completion was delayed by his untimely death in 1837. The botanists Diederich Franz Leonhard von Schlechtendal (1797–1866) and Christian Eduard Langethal (1806–1878) continued the project and the monumental 12-volume work was published in 1855 by Friedrich Mauke of Jena. The work includes 1444 engraved plates, hand-coloured by Ernst Schenk (1796–1859), as well as descriptive text in German.
External links
Gallery of illustrations |
https://en.wikipedia.org/wiki/Trembling%20hand%20perfect%20equilibrium | In game theory, trembling hand perfect equilibrium is a type of refinement of a Nash equilibrium that was first proposed by Reinhard Selten. A trembling hand perfect equilibrium is an equilibrium that takes the possibility of off-the-equilibrium play into account by assuming that the players, through a "slip of the hand" or tremble, may choose unintended strategies, albeit with negligible probability.
Definition
First define a perturbed game. A perturbed game is a copy of a base game, with the restriction that only totally mixed strategies are allowed to be played.
A totally mixed strategy is a mixed strategy where every strategy (both pure and mixed) is played with non-zero probability.
This is the "trembling hands" of the players; they sometimes play a different strategy, other than the one they intended to play. Then define a strategy set S (in a base game) as being trembling hand perfect if there is a sequence of perturbed games that converge to the base game in which there is a series of Nash equilibria that converge to S.
Note: All completely mixed Nash equilibria are perfect.
Note 2: The mixed strategy extension of any finite normal-form game has at least one perfect equilibrium.
Example
The game represented in the following normal form matrix has two pure strategy Nash equilibria, namely and . However, only is trembling-hand perfect.
Assume player 1 (the row player) is playing a mixed strategy , for .
Player 2's expected payoff from playing L is:
Player 2's expected payoff from playing the strategy R is:
For small values of , player 2 maximizes his expected payoff by placing a minimal weight on R and maximal weight on L. By symmetry, player 1 should place a minimal weight on D and maximal weight on U if player 2 is playing the mixed strategy . Hence is trembling-hand perfect.
However, similar analysis fails for the strategy profile .
Assume player 2 is playing a mixed strategy . Player 1's expected payoff from playing U is:
Player 1's |
https://en.wikipedia.org/wiki/Sex%20determination%20in%20Silene | Silene is a flowering plant genus that has evolved a dioecious reproductive system. This is made possible through heteromorphic sex chromosomes expressed as XY. Silene recently evolved sex chromosomes 5-10 million years ago and are widely used by geneticists and biologists to study the mechanisms of sex determination since they are one of only 39 species across 14 families of angiosperm that possess sex-determining genes. Silene are studied because of their ability to produce offspring with a plethora of reproductive systems. The common inference drawn from such studies is that the sex of the offspring is determined by the Y chromosome.
Evolution of sex chromosomes
Biologists have found that sex chromosomes in plants originated from pairs of autosomes. As these chromosomes diverge from their autosomal ancestor and from each other as a homologous pair, they have the potential to increase or decrease in size due to mutation and recombination. In the case of Silene, the pair of automsomal chromosomes are transformed into heteromorphic sex-determining chromosomes expressed as XY. It is important to recognize that not all species of Silene have this sex determination system. A few, such as S. colpophylla, possess homomorphic sex chromosomes.
Plants with sex-determining chromosomes, like Silene, can develop uni-sexual reproductive structures because of the loss and gain of sex-determining genes. Mutations can cause female sterility, male sterility, or adverse combinations of genes that can lead to monoecy, gynodioecy, and dioecy.
Species of Silene with different reproductive systems
The mechanisms involved in the sex determination of Silene are complex and can lead to various reproductive systems among the offspring. The table below provides only a few examples of these possible systems. Those which are most commonly found within this genus are hermaphroditism (monoecious plant with both staminate and pistillate), dioecy (male and female reproductive systems found |
https://en.wikipedia.org/wiki/Counting%20lemma | The counting lemmas this article discusses are statements in combinatorics and graph theory. The first one extracts information from -regular pairs of subsets of vertices in a graph , in order to guarantee patterns in the entire graph; more explicitly, these patterns correspond to the count of copies of a certain graph in . The second counting lemma provides a similar yet more general notion on the space of graphons, in which a scalar of the cut distance between two graphs is correlated to the homomorphism density between them and .
Graph embedding version of counting lemma
Whenever we have an -regular pair of subsets of vertices in a graph , we can interpret this in the following way: the bipartite graph, , which has density , is close to being a random bipartite graph in which every edge appears with probability , with some error.
In a setting where we have several clusters of vertices, some of the pairs between these clusters being -regular, we would expect the count of small, or local patterns, to be roughly equal to the count of such patterns in a random graph. These small patterns can be, for instance, the number of graph embeddings of some in , or more specifically, the number of copies of in formed by taking one vertex in each vertex cluster.
The above intuition works, yet there are several important conditions that must be satisfied in order to have a complete statement of the theorem; for instance, the pairwise densities are at least , the cluster sizes are at least , and . Being more careful of these details, the statement of the graph counting lemma is as follows: Statement of the theorem
If is a graph with vertices and edges, and is a graph with (not necessarily disjoint) vertex subsets , such that for all and for every edge of the pair is -regular with density and , then contains at least many copies of with the copy of vertex in .
This theorem is a generalization of the triangle counting lemma, which states the above but |
https://en.wikipedia.org/wiki/EarthKosher | EarthKosher is an American company providing kosher certification. The main office is in Boulder, Colorado, with offices in California, New Jersey, Mexico City and Jerusalem. It is a member of the Association of Kashrus Organizations.
Rabbi Zushe Yosef Blech was a rabbinic consultant of EarthKosher from its inception, and was the senior kashrus administrator from 2007 until his death in 2018. In 2022 the senior kashrus administrator was Rabbi Sholom H. Adler.
The company also certifies vegan, Paleo and non-GMO products. Since 2018 it has operated an online certification platform.
See also
Hechsher
Kashrut
Kosher foods
Mashgiach |
https://en.wikipedia.org/wiki/Suillus%20pungens | Suillus pungens, commonly known as the pungent slippery jack or the pungent suillus, is a species of fungus in the genus Suillus. The fruit bodies of the fungus have slimy convex caps up to
wide. The mushroom is characterized by the very distinct color changes that occur in the cap throughout development. Typically, the young cap is whitish, later becoming grayish-olive to reddish-brown or a mottled combination of these colors. The mushroom has a dotted stem (stipe) up to long, and thick. On the underside on the cap is the spore-bearing tissue consisting of minute vertically arranged tubes that appear as a surface of angular, yellowish pores. The presence of milky droplets on the pore surface of young individuals, especially in humid environments, is a characteristic feature of this species. S. pungens can usually be distinguished from other similar Suillus species by differences in distribution, odor and taste. The mushroom is considered edible, but not highly regarded.
An ectomycorrhizal species, S. pungens forms an intimate mutualistic relationship between its underground mycelium and the young roots of the associated host tree. The fungus—limited in distribution to California—fruits almost exclusively with Monterey and bishop pine, two trees with small and scattered natural ranges concentrated in the West Coast of the United States. Several studies have investigated the role of S. pungens in the coastal Californian forest ecosystem it occupies. Although the species produces more fruit bodies than other competing ectomycorrhizal fungi in the same location, it is not a dominant root colonizer, and occupies only a small percentage of ectomycorrhizal root tips. The fungus's propensity to fruit prolifically despite minimal root colonization is a result of its ability to efficiently transfer nutrients from its host for its own use.
Taxonomy, classification, and phylogeny
The fungus was first described scientifically by American mycologists Harry D. Thiers and Ale |
https://en.wikipedia.org/wiki/Hubley%20Manufacturing%20Company | The Hubley Manufacturing Company was an American producer of a wide range of cast-iron toys, doorstops, and bookends. Toys, particularly motor vehicles and cap guns, were also produced in zinc alloy and plastic. The company is probably most well known for its detailed scale metal kits of Classic cars in about 1:20 scale. Starting in 1960, Hubley participated for a couple of years with Detroit automakers as a plastic promotional model maker. Many Hubley toys are now sought-after collectibles.
History
The Hubley Manufacturing Company was first incorporated in 1894 in Lancaster, Pennsylvania by John Hubley. The first Hubley toys appeared in 1909 and were made of cast-iron, with themes that ranged from horse-drawn vehicles and different breeds of dogs, to tractors, steam shovels and guns. Hubley's main competition in the early years was Arcade. Early toys were known for their complexity; a delicate 11 inch long Packard Straight 8, a five-ton truck that came complete with tools, a road roller that came in five different sizes, a steam shovel with working arms and shovel, and Chrysler Airflows with take-apart bodies. Hubley's was especially known for its many motorcycles, which were creative and often included sidecars or hooked to delivery vans that said, for example, "Say it with flowers" on the sides.
In the late 1930s, the company began shifting to diecast zinc alloy (mazac) molding similar to Tootsietoy which had been doing toys in diecast since 1933. Foreshadowing the post-war diecast boom, and perhaps in an attempt to steal some of Tootsietoys' thunder, new mazac and plastic Hubley toys were now called Kiddietoys – a name which was used at least until the mid-1950s. Household objects such as doorstops and bookends were also produced, but automobiles, trucks and airplanes gradually became Hubley's mainstay.
Hubley's casting process involved several steps. For a particular toy, bookend, or doorstop, metalworkers would first carve a wood form, or hammer out the b |
https://en.wikipedia.org/wiki/Affordable%20Connectivity%20Program | The Affordable Connectivity Program (ACP) is a United States government-sponsored program that aims to provide wireless internet for low-income households. Several companies have signed on to participate in the program, including Verizon Communications, Frontier Communications, T-Mobile, Spectrum, Cox, AT&T, Xfinity, Optimum and Comcast. The program is administered by the Federal Communications Commission. The Infrastructure Investment and Jobs Act provides $14.2 billion in funding for $30 subsidies for those with low incomes, and $75 subsidies on tribal lands.
History
2021
In 2021, US Congress passed a $1 trillion infrastructure package including $14.2 billion for the Affordable Connectivity Program. The program replaced the Emergency Broadband Benefit program, with $14 billion dedicated to the act. The ACB replaced the EBB on December 31, 2021.
When the act was remarked upon by US President Biden on May 9, 2022, close to 40% of American households qualified for assistance, i.e. households or individuals earned twice the poverty level or less. There are higher limits in Hawaii and Alaska. According to NPR, an estimated 48 million Americans qualified, with the plans to provide at least 100 megabits per second of speed for a maximum of $30. One person in the household must participate in government assistance programs, if the household is above 200% of the Federal Poverty Guidelines.
Twenty internet providers were initially involved, including regional companies such as Hawaiian Telcom and Jackson Energy Authority in Tennessee. The full list included Allo Communications, Altafiber, Altice USA, Astound, AT&T, Breezeline, Comcast, Comporium, Frontier, IdeaTek, Cox Communications, Jackson Energy Authority, MediaCom, MLGC, Spectrum, Verizon, Vermont Telephone Company, Vexus Fiber, and Wow! Internet, Cable, and TV. Aristata Communications joined the program in August 2023.
In 2021, Pew Research Center engaged in a study on the act along with the University of South |
https://en.wikipedia.org/wiki/Stickland%20fermentation | Stickland fermentation or The Stickland Reaction is the name for a chemical reaction that involves the coupled oxidation and reduction of amino acids to organic acids. The electron donor amino acid is oxidised to a volatile carboxylic acid one carbon atom shorter than the original amino acid. For example, alanine with a three carbon chain is converted to acetate with two carbons. The electron acceptor amino acid is reduced to a volatile carboxylic acid the same length as the original amino acid. For example, glycine with two carbons is converted to acetate.
In this way, amino acid fermenting microbes can avoid using hydrogen ions as electron acceptors to produce hydrogen gas. Amino acids can be Stickland acceptors, Stickland donors, or act as both donor and acceptor. Only histidine cannot be fermented by Stickland reactions, and is oxidised. With a typical amino acid mix, there is a 10% shortfall in Stickland acceptors, which results in hydrogen production. Under very low hydrogen partial pressures, increased uncoupled anaerobic oxidation has also been observed.
It occurs in proteolytic clostridiums such as:
C. perfringens,
C. difficile,
C. sporogenes,
and C. botulinum.
Additionally, sarcosine and betaine can act as electron acceptors. |
https://en.wikipedia.org/wiki/Consensus%20theorem | In Boolean algebra, the consensus theorem or rule of consensus is the identity:
The consensus or resolvent of the terms and is . It is the conjunction of all the unique literals of the terms, excluding the literal that appears unnegated in one term and negated in the other. If includes a term which is negated in (or vice versa), the consensus term is false; in other words, there is no consensus term.
The conjunctive dual of this equation is:
Proof
Consensus
The consensus or consensus term of two conjunctive terms of a disjunction is defined when one term contains the literal and the other the literal , an opposition. The consensus is the conjunction of the two terms, omitting both and , and repeated literals. For example, the consensus of and is . The consensus is undefined if there is more than one opposition.
For the conjunctive dual of the rule, the consensus can be derived from and through the resolution inference rule. This shows that the LHS is derivable from the RHS (if A → B then A → AB; replacing A with RHS and B with (y ∨ z) ). The RHS can be derived from the LHS simply through the conjunction elimination inference rule. Since RHS → LHS and LHS → RHS (in propositional calculus), then LHS = RHS (in Boolean algebra).
Applications
In Boolean algebra, repeated consensus is the core of one algorithm for calculating the Blake canonical form of a formula.
In digital logic, including the consensus term in a circuit can eliminate race hazards.
History
The concept of consensus was introduced by Archie Blake in 1937, related to the Blake canonical form. It was rediscovered by Samson and Mills in 1954 and by Quine in 1955. Quine coined the term 'consensus'. Robinson used it for clauses in 1965 as the basis of his "resolution principle". |
https://en.wikipedia.org/wiki/Acidilobus%20aceticus | Acidilobus aceticus is a thermoacidophilic (that is, both thermophilic and acidophilic) species of anaerobic archaea. The species was originally described in 2000 after being isolated from hot springs in Kamchatka. It is the type species of the genus Acidilobus.
Description
Acidilobus aceticus has a coccoid morphology of 1-2 μm diameter with a relatively thick S-layer. A. aceticus has an optimal growth temperature of 85°C (qualifying it as a hyperthermophile) and an optimal pH of 3.8. It is a non-motile obligate anaerobe with fermentative metabolism characterized by production of acetate under cell culture conditions tested; its name recognizes this property. Although its growth is accelerated by the presence of elemental sulfur, which is reduced to hydrogen sulfide, sulfur is not essential for growth. It is resistant to the antibiotics chloramphenicol, penicillin and streptomycin. A. aceticus differs from A. saccharovorans, the only other recognized species in the genus, in two major respects: it is non-motile whereas A. saccharovorans is flagellated; and it is capable of growth on a much narrower range of substrates. |
https://en.wikipedia.org/wiki/Columbian%20exchange | The Columbian exchange, also known as the Columbian interchange, was the widespread transfer of plants, animals, precious metals, commodities, culture, human populations, technology, diseases, and ideas between the New World (the Americas) in the Western Hemisphere, and the Old World (Afro-Eurasia) in the Eastern Hemisphere, in the late 15th and following centuries. It is named after the Italian explorer Christopher Columbus and is related to the European colonization and global trade following his 1492 voyage. Some of the exchanges were purposeful; some were accidental or unintended. Communicable diseases of Old World origin resulted in an 80 to 95 percent reduction in the number of Indigenous peoples of the Americas from the 15th century onwards, most severely in the Caribbean. The cultures of both hemispheres were significantly impacted by the migration of people (both free and enslaved) from the Old World to the New. European colonists and African slaves replaced Indigenous populations across the Americas, to varying degrees. The number of Africans taken to the New World was far greater than the number of Europeans moving to the New World in the first three centuries after Columbus.
The new contacts among the global population resulted in the interchange of a wide variety of crops and livestock, which supported increases in food production and population in the Old World. American crops such as maize, potatoes, tomatoes, tobacco, cassava, sweet potatoes, and chili peppers became important crops around the world. Old World rice, wheat, sugar cane, and livestock, among other crops, became important in the New World. American-produced silver flooded the world and became the standard metal used in coinage, especially in Imperial China.
The term was first used in 1972 by the American historian and professor Alfred W. Crosby in his environmental history book The Columbian Exchange. It was rapidly adopted by other historians and journalists.
Etymology
In 1972, Alfr |
https://en.wikipedia.org/wiki/Heterothermy | Heterothermy or heterothermia (from Greek ἕτερος heteros "other" and θέρμη thermē "heat") is a physiological term for animals that vary between self-regulating their body temperature, and allowing the surrounding environment to affect it. In other words, they exhibit characteristics of both poikilothermy and homeothermy.
Definition
Heterothermic animals are those that can switch between poikilothermic and homeothermic strategies. These changes in strategies typically occur on a daily basis or on an annual basis. More often than not, it is used as a way to dissociate the fluctuating metabolic rates seen in some small mammals and birds (e.g. bats and hummingbirds), from those of traditional cold blooded animals. In many bat species, body temperature and metabolic rate are elevated only during activity. When at rest, these animals reduce their metabolisms drastically, which results in their body temperature dropping to that of the surrounding environment. This makes them homeothermic when active, and poikilothermic when at rest. This phenomenon has been termed 'daily torpor' and was intensively studied in the Djungarian hamster. During the hibernation season, this animal shows strongly reduced metabolism each day during the rest phase while it reverts to endothermic metabolism during its active phase, leading to normal euthermic body temperatures (around 38 °C).
Larger mammals (e.g. ground squirrels) and bats show multi-day torpor bouts during hibernation (up to several weeks) in winter. During these multi-day torpor bouts, body temperature drops to ~1 °C above ambient temperature and metabolism may drop to about 1% of the normal endothermic metabolic rate. Even in these deep hibernators, the long periods of torpor is interrupted by bouts of endothermic metabolism, called arousals (typically lasting between 4–20 hours). These metabolic arousals cause body temperature to return to euthermic levels 35-37 °C. Most of the energy spent during hibernation is spent in arous |
https://en.wikipedia.org/wiki/Tangent%20cone | In geometry, the tangent cone is a generalization of the notion of the tangent space to a manifold to the case of certain spaces with singularities.
Definitions in nonlinear analysis
In nonlinear analysis, there are many definitions for a tangent cone, including the adjacent cone, Bouligand's contingent cone, and the Clarke tangent cone. These three cones coincide for a convex set, but they can differ on more general sets.
Clarke tangent cone
Let be a nonempty closed subset of the Banach space . The Clarke's tangent cone to at , denoted by consists of all vectors , such that for any sequence tending to zero, and any sequence tending to , there exists a sequence tending to , such that for all holds
Clarke's tangent cone is always subset of the corresponding contingent cone (and coincides with it, when the set in question is convex). It has the important property of being a closed convex cone.
Definition in convex geometry
Let K be a closed convex subset of a real vector space V and ∂K be the boundary of K. The solid tangent cone to K at a point x ∈ ∂K is the closure of the cone formed by all half-lines (or rays) emanating from x and intersecting K in at least one point y distinct from x. It is a convex cone in V and can also be defined as the intersection of the closed half-spaces of V containing K and bounded by the supporting hyperplanes of K at x. The boundary TK of the solid tangent cone is the tangent cone to K and ∂K at x. If this is an affine subspace of V then the point x is called a smooth point of ∂K and ∂K is said to be differentiable at x and TK is the ordinary tangent space to ∂K at x.
Definition in algebraic geometry
Let X be an affine algebraic variety embedded into the affine space , with defining ideal . For any polynomial f, let be the homogeneous component of f of the lowest degree, the initial term of f, and let
be the homogeneous ideal which is formed by the initial terms for all , the initial ideal of I. The tangent c |
https://en.wikipedia.org/wiki/Nonmetal | A nonmetal is a chemical element that mostly lacks metallic properties. Seventeen elements are generally considered nonmetals, though some authors recognize more or fewer depending on the properties considered most representative of metallic or nonmetallic character. Some borderline elements further complicate the situation.
Nonmetals tend to have low density and high electronegativity (the ability of an atom in a molecule to attract electrons to itself). They range from colorless gases like hydrogen to shiny solids like the graphite form of carbon. Nonmetals are often poor conductors of heat and electricity, and when solid tend to be brittle or crumbly. In contrast, metals are good conductors and most are pliable. While compounds of metals tend to be basic, those of nonmetals tend to be acidic.
The two lightest nonmetals, hydrogen and helium, together make up about 98% of the observable ordinary matter in the universe by mass. Five nonmetallic elements—hydrogen, carbon, nitrogen, oxygen, and silicon—make up the overwhelming majority of the Earth's crust, atmosphere, oceans and biosphere.
The distinct properties of nonmetallic elements allow for specific uses that metals often cannot achieve. Elements like hydrogen, oxygen, carbon, and nitrogen are essential building blocks for life itself. Moreover, nonmetallic elements are integral to industries such as electronics, energy storage, agriculture, and chemical production.
Most nonmetallic elements were not identified until the 18th and 19th centuries. While a distinction between metals and other minerals had existed since antiquity, a basic classification of chemical elements as metallic or nonmetallic emerged only in the late 18th century. Since then nigh on two dozen properties have been suggested as single criteria for distinguishing nonmetals from metals.
Definition and applicable elements
Properties mentioned hereafter refer to the elements in their most stable forms in ambient conditions unless otherwise |
https://en.wikipedia.org/wiki/Test%20automation%20management%20tools | Test automation management tools are specific tools that provide a collaborative environment that is intended to make test automation efficient, traceable and clear for stakeholders. Test automation is becoming a cross-discipline (i.e. a mix of both testing and development practices.)
Motivation
Test automation systems usually need more reporting, analysis and meaningful information about project status. Test management systems target manual effort and do not give all the required information.
Test automation management systems leverage automation efforts towards efficient and continuous processes of delivering test execution and new working tests by:
Making transparent, meaningful and traceable reporting for all project stakeholders.
Easing test debugging through test results analysis workflow.
Providing valuable metrics and key performance indicators – both technical and business-wise (trend analysis, benchmarking, gap analysis, root cause analysis and risk point analysis).
Grid benchmarking and comparison of test execution days reduces analysis and review effort.
Clean traceability with other testing artifacts (test cases, data, issues, etc.).
Organizing historical data.
Post-project analysis and automation performance assessment. (Progress of test coverage shows the group performance.)
Compliance with Agile
Test automation management tools fit Agile Systems Development Life Cycle methodologies. In most cases, test automation covers continuous changes to minimize manual regression testing. Changes are usually noted by monitoring test log diffs. For example, differences in the number of failures signal probable changes either in AUT or in test code (broken test code base, instabilities) or in both. Quick notice of changes and unified workflow of results analysis reduces testing costs and increases project quality.
TDD
Test-driven development utilizes test automation as the primary driver to rapid and high-quality software production. Concepts of green |
https://en.wikipedia.org/wiki/Antiholomorphic%20function | In mathematics, antiholomorphic functions (also called antianalytic functions) are a family of functions closely related to but distinct from holomorphic functions.
A function of the complex variable z defined on an open set in the complex plane is said to be antiholomorphic if its derivative with respect to exists in the neighbourhood of each and every point in that set, where is the complex conjugate.
A definition of antiholomorphic function follows: "[a] function of one or more complex variables [is said to be anti-holomorphic if (and only if) it] is the complex conjugate of a holomorphic function ."
One can show that if f(z) is a holomorphic function on an open set D, then f() is an antiholomorphic function on , where is the reflection against the x-axis of D, or in other words, is the set of complex conjugates of elements of D. Moreover, any antiholomorphic function can be obtained in this manner from a holomorphic function. This implies that a function is antiholomorphic if and only if it can be expanded in a power series in in a neighborhood of each point in its domain. Also, a function f(z) is antiholomorphic on an open set D if and only if the function is holomorphic on D.
If a function is both holomorphic and antiholomorphic, then it is constant on any connected component of its domain. |
https://en.wikipedia.org/wiki/Crossing%20%28physics%29 | In quantum field theory, a branch of theoretical physics, crossing is the property of scattering amplitudes that allows antiparticles to be interpreted as particles going backwards in time.
Crossing states that the same formula that determines the S-matrix elements and scattering amplitudes for particle to scatter with and produce particle and will also give the scattering amplitude for to go into , or for to scatter with to produce . The only difference is that the value of the energy is negative for the antiparticle.
The formal way to state this property is that the antiparticle scattering amplitudes are the analytic continuation of particle scattering amplitudes to negative energies. The interpretation of this statement is that the antiparticle is in every way a particle going backwards in time.
History
Murray Gell-Mann and Marvin Leonard Goldberger introduced crossing symmetry in 1954. Crossing had already been implicit in the work of Richard Feynman, but came to its own in the 1950s and 1960s as part of the analytic S-matrix program.
Overview
Consider an amplitude . We concentrate our attention on one of the incoming particles with momentum p. The quantum field , corresponding to the particle is allowed to be either bosonic or fermionic. Crossing symmetry states that we can relate the amplitude of this process to the amplitude of a similar process with an outgoing antiparticle replacing the incoming particle : .
In the bosonic case, the idea behind crossing symmetry can be understood intuitively using Feynman diagrams. Consider any process involving an incoming particle with momentum p. For the particle to give a measurable contribution to the amplitude, it has to interact with a number of different particles with momenta via a vertex. Conservation of momentum implies . In case of an outgoing particle, conservation of momentum reads as . Thus, replacing an incoming boson with an outgoing antiboson with opposite momentum yields the same S-matrix el |
https://en.wikipedia.org/wiki/Transcription%20factor%20DP | In molecular biology, transcription factor DP (Dimerization Partner) is a family of proteins which function as transcription factors.
DP forms a heterodimer with E2F and regulates genes involved in cell cycle progression. The transcriptional activity of E2F is inhibited by the retinoblastoma protein which binds to the E2F-DP heterodimer and negatively regulates the G1-S transition.
See also
E2F
TFDP1
TFDP2 |
https://en.wikipedia.org/wiki/Tevatron | The Tevatron was a circular particle accelerator (active until 2011) in the United States, at the Fermi National Accelerator Laboratory (also known as Fermilab), east of Batavia, Illinois, and is the second highest energy particle collider ever built, after the Large Hadron Collider (LHC) of the European Organization for Nuclear Research (CERN) near Geneva, Switzerland. The Tevatron was a synchrotron that accelerated protons and antiprotons in a ring to energies of up to 1 TeV, hence its name. The Tevatron was completed in 1983 at a cost of $120 million and significant upgrade investments were made during its active years of 1983–2011.
The main achievement of the Tevatron was the discovery in 1995 of the top quark—the last fundamental fermion predicted by the Standard Model of particle physics. On July 2, 2012, scientists of the CDF and DØ collider experiment teams at Fermilab announced the findings from the analysis of around 500 trillion collisions produced from the Tevatron collider since 2001, and found that the existence of the suspected Higgs boson was highly likely with a confidence of 99.8%, later improved to over 99.9%.
The Tevatron ceased operations on 30 September 2011, due to budget cuts and because of the completion of the LHC, which began operations in early 2010 and is far more powerful (planned energies were two 7 TeV beams at the LHC compared to 1 TeV at the Tevatron). The main ring of the Tevatron will probably be reused in future experiments, and its components may be transferred to other particle accelerators.
History
December 1, 1968, saw the breaking of ground for the linear accelerator (linac). The construction of the Main Accelerator Enclosure began on October 3, 1969, when the first shovel of earth was turned by Robert R. Wilson, NAL's director. This would become the 6.3 km circumference Fermilab's Main Ring.
The linac first 200 MeV beam started on December 1, 1970. The booster first 8 GeV beam was produced on May 20, 1971. On June 30, |
https://en.wikipedia.org/wiki/Mohammad%20Hajiaghayi | Mohammad Taghi Hajiaghayi () is a computer scientist known for his work in algorithms, game theory, social networks, network design, graph theory, and big data. He has over 200 publications with over 185 collaborators and 10 issued patents.
He is the Jack and Rita G. Minker Professor at the University of Maryland Department of Computer Science.
Professional career
Hajiaghayi received his PhD in applied mathematics and computer science from Massachusetts Institute of Technology in 2005 advised by Erik Demaine and F. Thomson Leighton.
His thesis was The Bidimensionality Theory and Its Algorithmic Applications. It founded the theory of bidimensionality which later received the Nerode Prize and was the topic of workshops.
Hajiaghayi has been the coach of the
University of Maryland ACM International Collegiate Programming team in the World Finals.
Honors and awards
Hajiaghayi's has received National Science Foundation CAREER Award (2010), Office of Naval Research Young Investigator Award (2011), University of Maryland Graduate Faculty Mentor of the Year Award (2015), as well as Google Faculty Research Awards (2010 & 2014). So far Hajiaghayi has raised more than $4 million in terms of grant award money from government and industry since joining the University of Maryland.
With his co-authors Erik Demaine, Fedor Fomin, and Dimitrios Thilikos, he received the 2015 European Association for Theoretical Computer Science Nerode Prize for his work (also the topic of his Ph.D. thesis) on bidimensionality, a general technique for developing both fixed-parameter tractable exact algorithms and approximation algorithms for a wide class of algorithmic problems on graphs.
Hajiaghayi has been elected as an ACM Fellow in 2018 "for contributions to the fields of algorithmic graph theory and algorithmic game theory."
Hajiaghayi has been elected as an IEEE Fellow in 2019 "for contributions to algorithmic graph theory and to algorithmic game theory." Hajiaghayi has been elected as a |
https://en.wikipedia.org/wiki/Mathematics%20of%20paper%20folding | The discipline of origami or paper folding has received a considerable amount of mathematical study. Fields of interest include a given paper model's flat-foldability (whether the model can be flattened without damaging it), and the use of paper folds to solve up-to cubic mathematical equations.
Computational origami is a recent branch of computer science that is concerned with studying algorithms that solve paper-folding problems. The field of computational origami has also grown significantly since its inception in the 1990s with Robert Lang's TreeMaker algorithm to assist in the precise folding of bases. Computational origami results either address origami design or origami foldability. In origami design problems, the goal is to design an object that can be folded out of paper given a specific target configuration. In origami foldability problems, the goal is to fold something using the creases of an initial configuration. Results in origami design problems have been more accessible than in origami foldability problems.
History
In 1893, Indian civil servant T. Sundara Row published Geometric Exercises in Paper Folding which used paper folding to demonstrate proofs of geometrical constructions. This work was inspired by the use of origami in the kindergarten system. Row demonstrated an approximate trisection of angles and implied construction of a cube root was impossible.
In 1922, Harry Houdini published "Houdini's Paper Magic," which described origami techniques that drew informally from mathematical approaches that were later formalized.
In 1936 Margharita P. Beloch showed that use of the 'Beloch fold', later used in the sixth of the Huzita–Hatori axioms, allowed the general cubic equation to be solved using origami.
In 1949, R C Yeates' book "Geometric Methods" described three allowed constructions corresponding to the first, second, and fifth of the Huzita–Hatori axioms.
The Yoshizawa–Randlett system of instruction by diagram was introduced in 1961.
I |
https://en.wikipedia.org/wiki/Symplectization | In mathematics, the symplectization of a contact manifold is a symplectic manifold which naturally corresponds to it.
Definition
Let be a contact manifold, and let . Consider the set
of all nonzero 1-forms at , which have the contact plane as their kernel. The union
is a symplectic submanifold of the cotangent bundle of , and thus possesses a natural symplectic structure.
The projection supplies the symplectization with the structure of a principal bundle over with structure group .
The coorientable case
When the contact structure is cooriented by means of a contact form , there is another version of symplectization, in which only forms giving the same coorientation to as are considered:
Note that is coorientable if and only if the bundle is trivial. Any section of this bundle is a coorienting form for the contact structure.
Differential topology
Structures on manifolds
Symplectic geometry |
https://en.wikipedia.org/wiki/Eco-industrial%20development | Eco-industrial development (EID) is a framework for industry to develop while reducing its impact on the environment. It uses a closed loop production cycle to tackle a broad set of environmental challenges such as soil and water pollution, desertification, species preservation, energy management, by-product synergy, resource efficiency, air quality, etc.
Mutually beneficial connections among industry, natural systems, energy, material and local communities become central factors in designing industrial production processes.
The approach itself is largely voluntary and market-driven but often pressed ahead by favorable government treatment or efforts of development co-operation.
History
Since the early 1990s the idea of EID evolved from biological symbiosis. This concept was adopted by industrial ecologists in the search for innovative approaches to solve problems of waste, energy shortage and degradation of the environment. A continuous approach towards improving both environmental and economic outcomes is used.
In 1992, the international community officially connected development co-operation to sustainable environmental protection for the first time. At the United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro, Brazil nearly 180 states signed the conference's Rio Declaration. Although non-binding, the Rio Declaration on Environment and Development laid out 27 principles that shall guide the increasing inter-connectedness of development cooperation and sustainability. Moreover, the documents drafting was accompanied by a presentation describing the idea of eco-industrial development for the first time.
In the following years, EID became popular throughout the United States. The recently elected Clinton administration installed a summit of business, labor, government and environmental protection representatives to further develop the approach. This summit established the idea of eco-industrial parks but soon realized that at first |
https://en.wikipedia.org/wiki/Monochromatization | Monochromatization in the context of accelerator physics is a theoretical principle used to increase center-of-mass energy resolution in high-luminosity particle collisions. The decrease of the collision energy spread can be accomplished without reducing the inherent energy spread of either of the two colliding beams, introducing opposite correlations between spatial position and energy at the interaction point (IP). In beam-optical terms, this can be accomplished through a non-zero dispersion function for both beams of opposite sign at the IP. The dispersion is determined by the respective lattice.
History
Monochromatization is a technique which has been proposed since a long time for reducing the centre-of-mass energy spread at e−e+ colliders, but this has never been used in any operational collider. This technique was first proposed by 1975 by A. Renieri to improve energy resolution of Italian collider Adone.
Implementation of a monochromatization scheme has been explored for several past colliders such as
ADONE (National Institute of Nuclear Physics)
SPEAR (SLAC National Accelerator Laboratory)
LEP (CERN)
but until now such a scheme has never been applied, or tested, in any operating collider. Nevertheless, studies for the FCC-ee are under development. |
https://en.wikipedia.org/wiki/Inverse%20transform%20sampling | Inverse transform sampling (also known as inversion sampling, the inverse probability integral transform, the inverse transformation method, Smirnov transform, or the golden rule) is a basic method for pseudo-random number sampling, i.e., for generating sample numbers at random from any probability distribution given its cumulative distribution function.
Inverse transformation sampling takes uniform samples of a number between 0 and 1, interpreted as a probability, and then returns the smallest number such that for the cumulative distribution function of a random variable. For example, imagine that is the standard normal distribution with mean zero and standard deviation one. The table below shows samples taken from the uniform distribution and their representation on the standard normal distribution.
We are randomly choosing a proportion of the area under the curve and returning the number in the domain such that exactly this proportion of the area occurs to the left of that number. Intuitively, we are unlikely to choose a number in the far end of tails because there is very little area in them which would require choosing a number very close to zero or one.
Computationally, this method involves computing the quantile function of the distribution — in other words, computing the cumulative distribution function (CDF) of the distribution (which maps a number in the domain to a probability between 0 and 1) and then inverting that function. This is the source of the term "inverse" or "inversion" in most of the names for this method. Note that for a discrete distribution, computing the CDF is not in general too difficult: we simply add up the individual probabilities for the various points of the distribution. For a continuous distribution, however, we need to integrate the probability density function (PDF) of the distribution, which is impossible to do analytically for most distributions (including the normal distribution). As a result, this method may be co |
https://en.wikipedia.org/wiki/Acesulfame%20potassium | Acesulfame potassium (, or ), also known as acesulfame K (K is the symbol for potassium) or Ace K, is a synthetic calorie-free sugar substitute (artificial sweetener) often marketed under the trade names Sunett and Sweet One. In the European Union, it is known under the E number (additive code) E950. It was discovered accidentally in 1967 by German chemist Karl Clauss at Hoechst AG (now Nutrinova). In chemical structure, acesulfame potassium is the potassium salt of 6-methyl-1,2,3-oxathiazine-4(3H)-one 2,2-dioxide. It is a white crystalline powder with molecular formula and a molecular weight of 201.24 g/mol.
Properties
Acesulfame K is 200 times sweeter than sucrose (common sugar), as sweet as aspartame, about two-thirds as sweet as saccharin, and one-third as sweet as sucralose. Like saccharin, it has a slightly bitter aftertaste, especially at high concentrations. Kraft Foods patented the use of sodium ferulate to mask acesulfame's aftertaste. Acesulfame K is often blended with other sweeteners (usually sucralose or aspartame). These blends are reputed to give a more sucrose-like taste whereby each sweetener masks the other's aftertaste, or exhibits a synergistic effect by which the blend is sweeter than its components. Acesulfame potassium has a smaller particle size than sucrose, allowing for its mixtures with other sweeteners to be more uniform.
Unlike aspartame, acesulfame K is stable under heat, even under moderately acidic or basic conditions, allowing it to be used as a food additive in baking, or in products that require a long shelf life. Although acesulfame potassium has a stable shelf life, it can eventually degrade to acetoacetamide, which is toxic in high doses. In carbonated drinks, it is almost always used in conjunction with another sweetener, such as aspartame or sucralose. It is also used as a sweetener in protein shakes and pharmaceutical products, especially chewable and liquid medications, where it can make the active ingredients more pa |
https://en.wikipedia.org/wiki/MCACEA | MCACEA (Multiple Coordinated Agents Coevolution Evolutionary Algorithm) is a general framework that uses a single evolutionary algorithm (EA) per agent sharing their optimal solutions to coordinate the evolutions of the EAs populations using cooperation objectives. This framework can be used to optimize some characteristics of multiple cooperating agents in mathematical optimization problems. More specifically, due to its nature in which both individual and cooperation objectives are optimize, MCACEA is used in multi-objective optimization problems.
Description and implementation
MCACEA, uses multiple EAs (one per each agent) that evolve their own populations to find the best solution for its associated problem according to their individual and cooperation constraints and objective indexes. Each EA is an optimization problem that runs in parallel and that exchanges some information with the others during its evaluation step. This information is needed to let each EA to measure the coordination objectives of the solutions encoded in its own population, taking into account the possible optimal solutions of the remaining populations of the other EAs. With this purpose, each single EA receives information related to the best solutions of the remaining ones before evaluating the cooperative objectives of each possible solution of its own population.
As the cooperation objective values depend on the best solutions of the other populations and the optimality of a solution depends both on the individual and cooperation objectives, it is not really possible to select and send the best solution of
each planner to the others. However, MCACEA divides the evaluation step inside each EA in three parts: In the first part, the
EAs identify the best solution considering only its individual objective values and send it to the others EAs; in the second part, the cooperation objective values of all solutions are calculated taking into account the received information; and in the th |
https://en.wikipedia.org/wiki/Salacca%20affinis | Salacca affinis, also known as red salak, red snakefruit salak, red snakefruit, buah ridan salak, buah ridan, linsum, salak hutan, buah manau, kelubi, buah rotan, and ridan, is a flowering shrub in the family Arecaceae. The specific epithet (affinis) comes from Latin "ad finis", meaning "at the boundary", and refers to its resemblance with the congener species Salacca zalacca.
Distribution
Salacca affinis is native to Singapore, Peninsular Malaysia, Borneo, Java, and Sumatra, and occurs in the understory of rainforests, especially near ponds and swamps.
Description
It is a dioecious, acaulescent, and cespitose plant, and forms large, spiny tufts. The stems are usually underground or creeping, but can measure up to in height. The petioles measure up to 1 meter in length and are covered in yellow-orange to brown spines, which measure up to 10 centimeters in length and occur in clusters of 2–4. The leaves are pale green, pinnate, and measure up to in length and in width. They are lanceolate in shape and drooping. The rachis are covered in irregularly arranged spines, similar to the petioles. The topmost leaves have toothed, almost torn tips. The inflorescences are axillary and are subtended by leafy bracts. The male inflorescences measure in length and are ramified and have elongated and flattened spines bearing male flowers on cylindrical rachillae shaped like an ear. The single flower measures in length. Female inflorescences are shorter than males ones, measuring up to in length, and are ramified with female flowers borne on rachillae shaped like an ear. Female flowers measure up to in length. The fruit is somewhat ovate in shape, measuring in length and in width, and is tapered at both ends. They are red when ripe and have smooth scales, hence the name "snakefruit". It normally contains up to 3 pale yellow to white seeds and takes form at the center of the plant, making them hard to reach due to the abundance of spines. It is edible and is said to have a |
https://en.wikipedia.org/wiki/Computational%20visualistics | The term Computational visualistics addresses the whole range of scientifically investigating pictures "in" the computer.
Overview
Images take a rather prominent place in contemporary life in western societies. Together with language, they have been connected to human culture from the very beginning. For about one century – after several millennia of written word's dominance – their part is increasing again remarkably. Steps toward a general science of images, which we may call 'general visualistics' in analogy to general linguistics, have only been taken recently. So far, a unique scientific basis for circumscribing and describing the heterogeneous phenomenon "image" in an interpersonally verifiable manner has still been missing while distinct aspects falling in the domain of visualistics have predominantly been dealt with in several other disciplines, among them in particular philosophy, psychology, and art history. Last (though not least), important contributions to certain aspects of the new science of images have come from computer science.
In computer science, too, considering pictures evolved originally along several more or less independent questions, which lead to proper sub-disciplines: computer graphics is certainly the most "visible" among them. Only recently, the effort has been increased to finally form a unique and partially autonomous branch of computer science dedicated to images. In analogy to computational linguistics, the artificial expression computational visualistics is used for addressing the whole range of investigating scientific pictures "in" the computer.
Areas covered
For a science of images within computer science, the abstract data type "image" (or perhaps several such types) stands in the center of interest together with the potential implementations. There are three main groups of algorithms for that data type to be considered in computational visualistics:
Algorithms from "image" to "image"
In the field called image processin |
https://en.wikipedia.org/wiki/Knowledge%20Based%20Software%20Assistant | The Knowledge Based Software Assistant (KBSA) was a research program funded by the United States Air Force. The goal of the program was to apply concepts from artificial intelligence to the problem of designing and implementing computer software. Software would be described by models in very high level languages (essentially equivalent to first order logic) and then transformation rules would transform the specification into efficient code. The air force hoped to be able to generate the software to control weapons systems and other command and control systems using this method. As software was becoming ever more critical to USAF weapons systems it was realized that improving the quality and productivity of the software development process could have significant benefits for the military, as well as for information technology in other major US industries.
History
In the early 1980s the United States Air Force realized that they had received significant benefits from applying artificial intelligence technologies to solving expert problems such as the diagnosis of faults in aircraft. The air force commissioned a group of researchers from the artificial intelligence and formal methods communities to develop a report on how such technologies might be used to aid in the more general problem of software development.
The report described a vision for a new approach to software development. Rather than define specifications with diagrams and manually transform them to code as was the current process, the Knowledge Based Software Assistant (KBSA) vision was to define specifications in very high level languages and then to use transformation rules to gradually refine the specification into efficient code on heterogeneous platforms.
Each step in the design and refinement of the system would be recorded as part of an integrated repository. In addition to the artifacts of software development the processes, the various definitions and transformations, would also be recorded in |
https://en.wikipedia.org/wiki/Logarithmic%20conformal%20field%20theory | In theoretical physics, a logarithmic conformal field theory is a conformal field theory in which the
correlators of the basic fields are allowed to be logarithmic at short distance, instead of being powers of the fields' distance. Equivalently, the dilation operator is not diagonalizable.
Examples of logarithmic conformal field theories include critical percolation.
In two dimensions
Just like conformal field theory in general, logarithmic conformal field theory has been particularly well-studied in two dimensions. Some two-dimensional logarithmic CFTs have been solved:
The Gaberdiel–Kausch CFT at central charge , which is rational with respect to its extended symmetry algebra, namely the triplet algebra.
The Wess–Zumino–Witten model, based on the simplest non-trivial supergroup.
The triplet model at is also rational with respect to the triplet algebra. |
https://en.wikipedia.org/wiki/Toughie%20%28frog%29 | Toughie was the last known living Rabbs' fringe-limbed treefrog. The species, scientifically known as Ecnomiohyla rabborum, is thought to be extinct, as the last specimen—Toughie—died in captivity on September 26, 2016.
Captivity
Toughie was captured as an adult in Panama in 2005, when researchers went on a conservation mission to rescue species from Batrachochytrium dendrobatidis, a fungus deadly to amphibians. Toughie was one of "several dozen" frogs and tadpoles of the same species to be transported back to the United States.
Toughie lived at the Atlanta Botanical Garden in Georgia. At the Garden, he was placed in a special containment area called the "frogPOD", a biosecure enclosure. Visitors to the Garden are not allowed to visit the frogPOD, as it is used to house critically endangered animals. While in captivity at the Garden, Toughie sired tadpoles with a female, but none survived. After the female died, the only other known specimen in the world was a male, leaving Toughie no other options of reproducing. The other male, who lived at the Zoo Atlanta, was euthanized on February 17, 2012, due to health concerns.
Since Toughie was brought in as an adult to the Garden, they do not know his age but estimated that he was at least 12 years old. On December 15, 2014, Toughie was recorded vocalizing again. It was his first known call since being collected as an adult in 2005.
Toughie died on September 26, 2016, at the Garden.
Personal characteristics
Toughie was given his name by Mark Mandica's son Anthony. Mark Mandica was Toughie's caretaker for many years at the Atlanta Botanical Garden.
Toughie did not like to be handled. He would pinch a handler's hand in an attempt to "say 'let me go'", according to handler Leslie Phillips. She continued with, "For me it is incredibly motivating working with the Rabbs' frog. Having him here is a constant reminder of what can potentially happen to other species if we don't continue the conservation work that we do here a |
https://en.wikipedia.org/wiki/Kind%20code | In patent law, a kind code, or WIPO Standard ST.16 code, is a code used on patent documents published by intellectual property offices to distinguish different kinds of patent documents. A kind code includes a letter, and in many cases a number, used to distinguish the kind of patent document (e.g., publication of an application for a utility patent (patent application publication), patent, plant patent application publication, plant patent, or design patent) and the level of publication (e.g., first publication, second publication, or corrected publication). The recommended use is the two-letter country code followed by the patent document number and then the kind code, e.g., "US 7,654,321 B1" for U.S. Patent No. 7,654,321 where there was no previously-published patent application publication, and "US 2003/1234567 A1" for U.S. Patent Application Publication No. 2003/1234567, published in 2003.
In the European Patent Office
The European Patent Office (EPO) uses kind codes such as the following. Kind codes for patent applications begin with A and include
A1, for an application published with a European search report;
A2, for an application published without a European search report; and
A3, for a later publication of the European search report.
Kind codes for granted patents begin with B and chiefly include B1 for a European patent specification (granted patent).
In Japan
The Japan Patent Office (JPO) uses kind codes including
A for publications of patent applications; and
B1 and B2 for publications of granted patents.
In the United States
In the United States, effective January 2, 2001, the kind codes indicate a variety of documents published by the United States Patent and Trademark Office (USPTO), most importantly patent application publications and patents. The kind codes include
A1, for a patent application publication (pre-grant publication);
B1, for a patent issuing from an application that was not previously published as a pre-grant publication; and
B2, |
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