Topics matching isTruncated.dot


Monus

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Monus

In mathematics, monus is an operator on certain commutative monoids that are not groups. A commutative monoid on which a monus operator is defined is called a commutative monoid with monus, or CMM. The monus operator may be denoted with the − symbol because the natural numbers are a CMM under subtraction; it is also denoted with the ∸ symbol to distinguish it from the standard subtraction operator. Notation glyph Unicode name Unicode code point[1] HTML character entity reference HTML/XML numeric character references TeX ∸ DOT MINUS U+2238 ∸ \dot - − MINUS SIGN U+2212 − − - Definition Let ( M , + , 0 ) {\displaystyle (M,+,0)} be a commutative monoid. Define a binary relation ≤ {\displaystyle \leq } on this monoid as follows: for any two elements a {\displaystyle a} and b {\displaystyle b} , define a ≤ b {\displaystyle a\leq b} if there exists an element c {\displaystyle c} such that a + c = b {\displaystyle a+c=b

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Abstract algebra

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Full stop

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Full stop

The full point, full stop (Commonwealth English) or period (North American English) is a punctuation mark. It is used for several purposes, the most frequent of which is to mark the end of a declaratory sentence (as opposed to a question or exclamation); this sentence-terminal use is properly, or the precise meaning of, full stop. The full stop is also often used alone to indicate omitted characters (or in an ellipsis, "..." to indicate omitted words). It may be placed after an initial letter used to stand for a name, or sometimes after each individual letter in an initialism or acronym, for example, "U.S.A."; however, this style is declining, and many initialisms like UK or NATO have individually become accepted norms. A full stop is also frequently used at the end of word abbreviations – in British usage, primarily truncations like Rev., but not after contractions like Revd; however, in American English it is used in both cases. The full point also has multiple contexts in mathematics and computing, where

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Typographical symbols

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Ancient Greek punctuation

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Punctuation

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Truncated octahedron

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Truncated octahedron

Truncated octahedron (Click here for rotating model) Type Archimedean solidUniform polyhedron Elements F = 14, E = 36, V = 24 (χ = 2) Faces by sides 6{4}+8{6} Conway notation tObT Schläfli symbols t{3,4}tr{3,3} or t { 3 3 } {\displaystyle t{\begin{Bmatrix}3\\3\end{Bmatrix}}} t{3,4} or t{3,3} Wythoff symbol 2 4 | 33 3 2 | Coxeter diagram Symmetry group O, B, [4,3], (*432), order 48T, [3,3] and (*332), order 24 Rotation group O, [4,3]+, (432), order 24 Dihedral angle 4-6: arccos(−1/√3) = 125°15′51″6-6: arccos(−1/3) = 109°28′16″ References U, C, W Properties Semiregular convex parallelohedronpermutohedron Colored faces 4.6.6(Vertex figure) Tetrakis hexahedron(dual polyhedron) Net In geometry, the truncated octahedron is an Archimedean solid. It has 14 faces (8 regular hexagonal and 6 square), 36 edges, and 24 vertices. Since each of its faces has point symmetry the truncated octahedron is a zonohedron. It is also the Goldberg polyhed

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2-chromatic graphs

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Graphs of edges 36

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Graphs of vertices 24

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Roger von Oech

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Roger von Oech

Roger von Oech (born February 16, 1948) is an American speaker, conference organizer, author, and toy-maker whose focus has been on the study of creativity.[1][2][3] Professional life In 1975, von Oech earned his Ph.D. from Stanford University in the self-created interdisciplinary program "History of Ideas"[2] Shortly afterwards, he began providing services in creativity consulting, working with companies such as Apple, IBM, Disney, Sony, and Intel. In the 1980s, he created and produced the "Innovation in Industry" conference series in Palo Alto, which included Silicon Valley entrepreneurs such as Steve Jobs, Bill Gates, Bob Metcalfe, Charles Schwab, Alan Kay, and Nolan Bushnell of Atari.[4] Decks Creative Whack Pack In 1989, von Oech created the Creative Whack Pack, a deck of 64 cards with illustrations and strategies for stimulating creativity. It was designed to be a portable version of his creativity workshops, and it has sold over a million copies. Creative Whack Company In 2004, he started the Cr

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American business writers

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Business speakers

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1940s births

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Schoharie limousine crash

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Schoharie limousine crash

In the early afternoon of October 6, 2018, a stretch limousine crashed at the junction of New York state routes 30 and 30A north of Schoharie ( skoh-HAIR-ee), 30 miles (48 km) west of Albany, killing 20—the driver, all 17 passengers, and two pedestrians who were in a nearby parking lot.[1][2] The passengers were mostly from communities around the Capital District, primarily Amsterdam, where they had gathered to begin their trip. They were on their way to celebrate a 30th birthday at Brewery Ommegang near Cooperstown. Among them were four sisters and two recently married couples. It was the deadliest transportation-related disaster in the United States since the 2009 Colgan Air Flight 3407 crash outside Buffalo killed 50;[3] it was also the deadliest road transportation disaster in the U.S. since a 2005 bus fire in Wilmer, Texas, killed 23 nursing home residents evacuating from the path of Hurricane Rita.[4] Investigation of the accident has revealed pre-existing problems with the limousine, the driver and t



Euler method

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Euler method

Illustration of the Euler method. The unknown curve is in blue, and its polygonal approximation is in red. Euler's method is a numerical method to solve first order first degree differential equation with a given initial value. It is the most basic explicit method for numerical integration of ordinary differential equations and is the simplest Runge–Kutta method. The Euler method is named after Leonhard Euler, who treated it in his book Institutionum calculi integralis (published 1768–1870).[1] The Euler method is a first-order method, which means that the local error (error per step) is proportional to the square of the step size, and the global error (error at a given time) is proportional to the step size. The Euler method often serves as the basis to construct more complex methods, e.g., predictor–corrector method. Informal geometrical description Consider the problem of calculating the shape of an unknown curve which starts at a given point and satisfies a given differential equation. Here, a differe

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Eponymous scientific concepts

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Leonhard Euler

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First order methods

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8.3 filename

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8.3 filename

An 8.3 filename[1] (also called a short filename or SFN) is a filename convention used by old versions of DOS and versions of Microsoft Windows prior to Windows 95 and Windows NT 3.5. It is also used in modern Microsoft operating systems as an alternate filename to the long filename for compatibility with legacy programs. The filename convention is limited by the FAT file system. Similar 8.3 file naming schemes have also existed on earlier CP/M, TRS-80, Atari, and some Data General and Digital Equipment Corporation minicomputer operating systems. Overview 8.3 filenames are limited to at most eight characters (after any directory specifier), followed optionally by a filename extension consisting of a period . and at most three further characters. For systems that only support 8.3 filenames, excess characters are ignored and if a file name has no extension, the ., if present, has no significance (that is, myfile and myfile. are equivalent). Furthermore, in these systems file and directory names are uppercase,

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DOS technology

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Windows architecture

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Filenames

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Anarsia acrotoma

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Anarsia acrotoma

Anarsia acrotoma is a moth of the family Gelechiidae. It was described by Meyrick in 1913. It is found in southern India.[1] The wingspan is about 10 mm. The forewings are light greyish-ochreons, irrorated with whitish and with a few scattered fuscous and blackish scales, as well as a short black dash beneath the costa near the base. There is a triangular blackish patch occupying the median third of the costa. The apex is truncate, reaching more than half across the wing and there is a very small dark fuscous spot on costa at three-fourth, and a black dot or dash beneath it. There are also indications of blackish dots round the posterior part of the costa and termen. The hindwings are grey, becoming iridescent-hyaline anteriorly.[2] References Anarsia at funet J. Bombay nat. hist. Soc. 22 (1): 169

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Moths of India

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Anarsia

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Moths described in 1913

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Milü

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Milü

Fractional approximations to π. The name Milü (Chinese: 密率; pinyin: mì lǜ; "close ratio"), also known as Zulü (Zu's ratio), is given to an approximation to π (pi) found by Chinese mathematician and astronomer, Zǔ Chōngzhī (祖沖之). Using Liu Hui's algorithm (which is based on the areas of regular polygons approximating a circle), Zu famously computed π to be between 3.1415926 and 3.1415927 and gave two rational approximations of π, 22/7 and 355/113, naming them respectively Yuelü 约率 (approximate ratio) and Milü. 355/113 is the best rational approximation of π with a denominator of four digits or fewer, being accurate to 6 decimal places. It is within 0.000009% of the value of π, or in terms of common fractions overestimates π by less than 1/3748629. The next rational number (ordered by size of denominator) that is a better rational approximation of π is 52163/16604, still only correct to 6 decimal places and hardly closer to π than 355/113. To be accurate to 7 decimal places, one needs to go as far as 86953/27

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History of science and technology in China

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Chinese words and phrases

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History of mathematics

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Floor and ceiling functions

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Floor and ceiling functions

Floor and ceiling functions Floor function Ceiling function In mathematics and computer science, the floor function is the function that takes as input a real number x {\displaystyle x} and gives as output the greatest integer less than or equal to x {\displaystyle x} , denoted floor ⁡ ( x ) = ⌊ x ⌋ {\displaystyle \operatorname {floor} (x)=\lfloor x\rfloor } . Similarly, the ceiling function maps x {\displaystyle x} to the least integer greater than or equal to x {\displaystyle x} , denoted ceil ⁡ ( x ) = ⌈ x ⌉ {\displaystyle \operatorname {ceil} (x)=\lceil x\rceil } .[1] For example, floor ⁡ ( 2.4 ) = ⌊ 2.4 ⌋ = 2 {\displaystyle \operatorname {floor} (2.4)=\lfloor 2.4\rfloor =2} and ceil ⁡ ( 2.4 ) = ⌈ 2.4 ⌉ = 3 {\displaystyle \operatorname {ceil} (2.4)=\lceil 2.4\rceil =3} while ⌊ 2 ⌋ = ⌈ 2 ⌉ = 2 {\displaystyle \lfloor 2\rfloor =\lceil 2\rceil =2} . Notation The notion of the integral part or integer part of x was first introduced by Adrien-M

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Unary operations

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Special functions

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Mathematical notation

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Dither

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Dither

A grayscale image represented in 1-bit black-and-white space with dithering Dither is an intentionally applied form of noise used to randomize quantization error, preventing large-scale patterns such as color banding in images. Dither is routinely used in processing of both digital audio and video data, and is often one of the last stages of mastering audio to a CD. A common use of dither is converting a greyscale image to black and white, such that the density of black dots in the new image approximates the average grey level in the original. Etymology …[O]ne of the earliest [applications] of dither came in World War II. Airplane bombers used mechanical computers to perform navigation and bomb trajectory calculations. Curiously, these computers (boxes filled with hundreds of gears and cogs) performed more accurately when flying on board the aircraft, and less well on ground. Engineers realized that the vibration from the aircraft reduced the error from sticky moving parts. Instead of moving in short je

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Computer graphic artifacts

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Audio engineering

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Digital signal processing

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.org

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.org

The domain name org is a generic top-level domain (gTLD) of the Domain Name System (DNS) used in the Internet. The name is truncated from organization. It was one of the original domains established in 1985, and has been operated by the Public Interest Registry since 2003. The domain was originally intended for non-profit entities, but this restriction was not enforced and has been removed. The domain is commonly used by schools, open-source projects, and communities, but also by some for-profit entities. The number of registered domains in org has increased from fewer than one million in the 1990s, to ten million as of June 2013. History The domain ".org" was one of the original top-level domains,[1] with com, us, edu, gov, mil and net, established in January 1985. It was originally intended for non-profit organizations or organizations of a non-commercial character that did not meet the requirements for other gTLDs. The MITRE Corporation was the first group to register an org domain with mitre.org in July

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Computer-related introductions in 1985

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Non-profit organizations

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Generic top-level domains

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Hoplomorpha caminodes

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Hoplomorpha caminodes

Hoplomorpha caminodes is a moth in the Oecophoridae family. It was described by Turner in 1916.[1] It is found in Australia, where it has been recorded from Queensland.[2] The wingspan is 13–15 mm. The forewings are pale reddish-ochreous, darker towards the costa and with a dark reddish dorsal streak, edged with whitish, from one-fifth to four-fifth, abruptly truncated posteriorly. A fuscous spot, indented posteriorly, is found before the tornus, from this a reddish-ochreous suffusion containing two minute fuscous dots extends more than half across the disc beyond the middle, and is preceded by a whitish dot. There is a short, outwardly oblique, reddish-ochreous streak from three-fourth of the costa and an interrupted, fuscous line from beneath the costa to the termen above the tornus. There is also a fine, fuscous terminal line. The hindwings are dark grey, towards the base ochreous-whitish.[3] References Beccaloni, G.; Scoble, M.; Kitching, I.; Simonsen, T.; Robinson, G.; Pitkin, B.; Hine, A.; Lyal, C

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Moths described in 1916

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Google Authenticator

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Google Authenticator

Google Authenticator is a software-based authenticator that implements two-step verification services using the Time-based One-time Password Algorithm (TOTP; specified in RFC 6238) and HMAC-based One-time Password algorithm (HOTP; specified in RFC 4226), for authenticating users of mobile applications by Google.[2] When logging into a site supporting Authenticator (including Google services) or using Authenticator-supporting third-party applications such as password managers or file hosting services, Authenticator generates a six- to eight-digit one-time password which users must enter in addition to their usual login details. Previous versions of the software were open-source but subsequent releases are proprietary.[3] Typical use case To use Authenticator, the app is first installed on a smartphone. It must be set up for each site with which it is to be used: the site provides a shared secret key to the user over a secure channel, to be stored in the Authenticator app. This secret key will be used for a

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Pages with syntax highlighting errors

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Computer-related introductions in 2010

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Computer access control

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Seven-segment display

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Seven-segment display

A typical 7-segment LED display component, with decimal point in a DIP-10 package A seven-segment display is a form of electronic display device for displaying decimal numerals that is an alternative to the more complex dot matrix displays. Seven-segment displays are widely used in digital clocks, electronic meters, basic calculators, and other electronic devices that display numerical information.[1] History A multiplexed 4-digit, seven-segment display with only 12 pins Seven-segment representation of figures can be found in patents as early as 1903 (in U.S. Patent 1,126,641), when Carl Kinsley invented a method of telegraphically transmitting letters and numbers and having them printed on tape in a segmented format. In 1908, F. W. Wood invented an 8-segment display, which displayed the number 4 using a diagonal bar (U.S. Patent 974,943). In 1910, a seven-segment display illuminated by incandescent bulbs was used on a power-plant boiler room signal panel.[2] They were also used to show the dialed tele

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Odites ricinella

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Odites ricinella

Odites ricinella is a moth in the Depressariidae family. It was described by Henry Tibbats Stainton in 1859. It is found in India.[1] The forewings gradually increase in breadth to beyond the middle, then become slightly narrower, the hind margin truncate, ochreous, with numerous small brown spots, and a larger darker spot on the disc before the middle. Towards the apex is frequently a curved row of brown dots. The hind margin is spotted with brown. The hindwings are whitish, with a few brown dots on the apical margin. The larvae feed on Ricinus communis, rolling up the edge of a leaf. They are bright green with a black head.[2] References "Odites Walsingham, 1891" at Markku Savela's Lepidoptera and Some Other Life Forms. Transactions of the Entomological Society of London (n.s.) 5: 116

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Depressariidae

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Moths described in 1859

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Automatic differentiation

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Automatic differentiation

In mathematics and computer algebra, automatic differentiation (AD), also called algorithmic differentiation or computational differentiation,[1][2] is a set of techniques to numerically evaluate the derivative of a function specified by a computer program. AD exploits the fact that every computer program, no matter how complicated, executes a sequence of elementary arithmetic operations (addition, subtraction, multiplication, division, etc.) and elementary functions (exp, log, sin, cos, etc.). By applying the chain rule repeatedly to these operations, derivatives of arbitrary order can be computed automatically, accurately to working precision, and using at most a small constant factor more arithmetic operations than the original program. Automatic differentiation is neither: Figure 1: How automatic differentiation relates to symbolic differentiation Symbolic differentiation, nor Numerical differentiation (the method of finite differences). Symbolic differentiation can lead to inefficient code and

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Differential calculus

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TensorFlow

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Periclimenes soror

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Periclimenes soror

Periclimenes soror, also called the starfish shrimp, is a species of shrimp that lives as a symbiont with sea stars. Periclimenes soror is a species of little shrimp with a truncated rostris, and showing a wide variety of coats, but often with a distinctive white stripe or white dots pattern on the back. The rest of the body varies with the host starfish: it is often "a deep purple red" when living on Culcita, Protoreaster or Pentaceraster, but red with a white dorsal stripe when living on Acanthaster, and can also be transparent[1] Adults reach up to 15 millimetres (0.6 in) long.[2] On an Acanthaster planci On a Culcita schmideliana Ecology and behaviour It lives commensally on starfishes, including the "crown-of-thorns" starfish, Acanthaster planci. Distribution This species has a wide distribution across the Indo-Pacific and in the Gulf of Panama.[1] References A. J. Bruce (1982). "The shrimps associated with Indo-West Pacific echinoderms, with the description of a new species in t

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Crustaceans described in 1904

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Animals described in 1904

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Palaemonoidea

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ISO 8601

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ISO 8601

ISO 8601 Data elements and interchange formats – Information interchange – Representation of dates and times is an international standard covering the exchange of date- and time-related data. It was issued by the International Organization for Standardization (ISO) and was first published in 1988. The purpose of this standard is to provide an unambiguous and well-defined method of representing dates and times, so as to avoid misinterpretation of numeric representations of dates and times, particularly when data are transferred between countries with different conventions for writing numeric dates and times. In general, ISO 8601 applies to representations and formats of dates in the Gregorian (and potentially proleptic Gregorian) calendar, of times based on the 24-hour timekeeping system (with optional UTC offset), of time intervals, and combinations thereof.[2] The standard does not assign any specific meaning to elements of the date/time to be represented; the meaning will depend on the context of its use.

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Specific calendars

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Time measurement systems

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Hypatima verticosa

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Hypatima verticosa

Hypatima verticosa is a moth in the Gelechiidae family. It was described by Meyrick in 1913.[1] It is found in southern India.[2] The wingspan is about 14 mm. The forewings are ochreous-whitish, irrorated with light brownish and fuscous and with a black white-circled dot near the base above the middle and a blackish white-edged triangular patch occupying more than the median third of the costa, its costal extremities cut off by a line oblique white strigulae, the apex truncate and reaching half across the wing. A black elongate mark rests on the termen beneath the apex. The hindwings are grey, thinly scaled and subhyaline anteriorly, with the veins and termen suffused with dark fuscous.[3] References Beccaloni, G.; Scoble, M.; Kitching, I.; Simonsen, T.; Robinson, G.; Pitkin, B.; Hine, A.; Lyal, C., eds. (2003). "Hypatima verticosa". The Global Lepidoptera Names Index. Natural History Museum. Retrieved May 25, 2018. Hypatima at funet J. Bombay nat. hist. Soc. 22 (1): 166

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Runge–Kutta methods

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Runge–Kutta methods

In numerical analysis, the Runge–Kutta methods are a family of implicit and explicit iterative methods, which include the well-known routine called the Euler Method, used in temporal discretization for the approximate solutions of ordinary differential equations.[1] These methods were developed around 1900 by the German mathematicians Carl Runge and Wilhelm Kutta. Comparison of the Runge-Kutta methods for the differential equation y'=sin(t)^2*y ( red is the exact solution) The Runge–Kutta method Slopes used by the classical Runge-Kutta method The most widely known member of the Runge–Kutta family is generally referred to as "RK4", the "classic Runge–Kutta method" or simply as "the Runge–Kutta method". Let an initial value problem be specified as follows: y ˙ = f ( t , y ) , y ( t 0 ) = y 0 . {\displaystyle {\dot {y}}=f(t,y),\quad y(t_{0})=y_{0}.} Here y {\displaystyle y} is an unknown function (scalar or vector) of time t {\displaystyle t} , which we would like to

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Numerical differential equations

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Bethlehem Pike

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Bethlehem Pike

Bethlehem Pike is a historic 42.21 mi (67.93 km) long road in the U.S. state of Pennsylvania, connecting Philadelphia and Bethlehem, Pennsylvania. It began as a Native American path called the Minsi Trail which developed into a colonial highway called the King's Road in the 1760s. Most of the route later became part of U.S. Route 309, now Pennsylvania Route 309. History Colonial Age The Bethlehem Pike originated from a Native American pathway known as the Minsi Trail. Named after the Minsi Indians, the trail was routed between the Blue Mountains and the lands to the south.[6] In December 1740, David Nitschmann and his party went to Bethlehem and Nazareth along this trail. A year later, a second party joined the first, traversing the same pathway. Nicolaus Zinzendorf, was included in the second party who visited the pioneers in the cabin along the banks of the Monocacy Creek. On Christmas Eve, Zinzendorf celebrated a famous love-feast service, during which the new settlement was named Bethlehem.[4] After th

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Transportation in Northampton County, Pennsylvania

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Transportation in Philadelphia

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Transportation in Montgomery County, Pennsylvania

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Paratoari

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Paratoari

"The Dots" of Paratoari as seen in NASA satellite photograph number C-S11-32W071-03 Pyramids of Pantiacolla Paratoari (also known as the Pyramids of Paratoari, Pyramids of Pantiacolla or "The Dots") is a site composed of pyramid-shaped natural formations in the Manu area of dense tropical rainforest in southeast Peru. It was first identified via NASA satellite photograph number C-S11-32W071-03, released in 1976. They subsequently garnered greater attention among South America aficionados through a series of three articles which questioned from afar what "The Dots" might truly represent (and settled upon a geological explanation being the most plausible) in 1977 - 1979 issues of the "South American Explorer" journal, written under the name of "Ursula Thiermann" by Don Montague, president of the South American Explorers Club. The next 20 years were filled with speculation as to the formations' true nature, as they appeared to be symmetrically spaced and uniform in shape, looking like a series of eight or m

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Cross Gramian

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Cross Gramian

In control theory, the cross Gramian ( W X {\displaystyle W_{X}} , also referred to by W C O {\displaystyle W_{CO}} ) is a Gramian matrix used to determine how controllable and observable a linear system is.[1][2] For the stable time-invariant linear system x ˙ = A x + B u {\displaystyle {\dot {x}}=Ax+Bu\,} y = C x {\displaystyle y=Cx\,} the cross Gramian is defined as: W X := ∫ 0 ∞ e A t B C e A t d t {\displaystyle W_{X}:=\int _{0}^{\infty }e^{At}BCe^{At}dt\,} and thus also given by the solution to the Sylvester equation: A W X + W X A = − B C {\displaystyle AW_{X}+W_{X}A=-BC\,} The triple ( A , B , C ) {\displaystyle (A,B,C)} is controllable and observable if and only if the matrix W X {\displaystyle W_{X}} is nonsingular, (i.e. W X {\displaystyle W_{X}} has full rank, for any t > 0 {\displaystyle t>0} ). If the associated system ( A , B , C ) {\displaystyle (A,B,C)} is furthe

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Matrices

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Analytic geometry

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Supergravity

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Supergravity

In theoretical physics, supergravity (supergravity theory; SUGRA for short) is a modern field theory that combines the principles of supersymmetry and general relativity; in contrast to non-gravitational supersymmetric theories such as the Minimal Supersymmetric Standard Model. Supergravity is the gauge theory of local supersymmetry. Since the supersymmetry (SUSY) generators form together with the Poincaré algebra a superalgebra, called the super-Poincaré algebra, supersymmetry a gauge theory makes gravity arise in a natural way.[1] In simple terms, scientists have identified four basic forces behind everything happening around us. They are electromagnetic force (the reason why electricity is produced or medicines give us relief), weak force (which relates to radioactivity), strong force (the force that binds up protons and neutrons within the atom) and gravitational force (the reason why apples fall to the ground and the moon revolves around the Earth). Quantum theory can explain the first three types of fo

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Supersymmetry

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Physics beyond the Standard Model

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Theories of gravitation

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Dragon's teeth (fortification)

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Dragon's teeth (fortification)

Dragon's teeth near Aachen, Germany, part of the Siegfried Line. Dragon's teeth (German: Drachenzähne) are square-pyramidal fortifications of reinforced concrete first used during the Second World War to impede the movement of tanks and mechanised infantry. The idea was to slow down and channel tanks into killing zones where they could easily be disposed of by anti-tank weapons. They were employed extensively, particularly on the Siegfried Line.[1][2][3] World War II Dragon's teeth were used by several armies in the European Theatre. The Germans made extensive use of them on the Siegfried Line and the Atlantic Wall. Typically, each "tooth" was 90 to 120 cm (3 to 4 ft) tall, depending on the precise model. Land mines were often laid between the individual "teeth", and further obstacles were constructed along the lines of "teeth", such as barbed wire to impede infantry or diagonally-placed steel beams to further hinder tanks. The French army employed them in the Maginot Line, while many were laid in the Un

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Nonconcatenative morphology

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Nonconcatenative morphology

Diagram of one version of the derivation of the Arabic word muslim in autosegmental phonology, with root consonants associating (shown by dotted grey lines). Nonconcatenative morphology, also called discontinuous morphology and introflection, is a form of word formation in which the root is modified and which does not involve stringing morphemes together sequentially.[1] Types Ablaut In English, for example, while plurals are usually formed by adding the suffix -s, certain words use nonconcatenative processes for their plural forms: foot → feet ; and many irregular verbs form their past tenses, past participles, or both in this manner: freeze → froze , frozen . This specific form of nonconcatenative morphology is known as base modification or ablaut, a form in which part of the root undergoes a phonological change without necessarily adding new phonological material. (In traditional Indo-Europeanist usage, these changes are termed ablaut only when they result from vowel gradations in Proto-Indo-Europea

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Linguistic morphology

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Caenorycta dryoxantha

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Caenorycta dryoxantha

Caenorycta dryoxantha is a moth in the family Xyloryctidae. It was described by Meyrick in 1922. It is found in New Guinea.[1] The wingspan is about 38 mm. The forewings are pale ochreous, with scattered dark brown scales and a dark brown dot near the base in the middle. There is an elongate brown patch sprinkled with dark fuscous extending along the dorsum from one-fifth to four-fifths, pointed anteriorly, reaching one-third across the wing and truncate posteriorly, the upper edge with an obtuse prominence suffused with dark fuscous before the middle. There is also an indistinct median line of dark brown suffusion from near the base to the termen. The second discal stigma is linear and dark fuscous and there is some brownish tinge on the tornal area. A dark fuscous mark is found on the costa at three-fourths. The hindwings are ochreous-yellow.[2] References funet.fi Ent. Mitt. 11 (2) : 45

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Moths described in 1922

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Mathematical optimization

topic

Mathematical optimization

Graph of a paraboloid given by z = f(x, y) = −(x² + y²) + 4. The global maximum at (x, y, z) = (0, 0, 4) is indicated by a blue dot. Nelder-Mead minimum search of Simionescu's function. Simplex vertices are ordered by their value, with 1 having the lowest (best) value. Mathematical optimization (alternatively spelled optimisation) or mathematical programming is the selection of a best element (with regard to some criterion) from some set of available alternatives.[1] Optimization problems of sorts arise in all quantitative disciplines from computer science and engineering to operations research and economics, and the development of solution methods has been of interest in mathematics for centuries.[2] In the simplest case, an optimization problem consists of maximizing or minimizing a real function by systematically choosing input values from within an allowed set and computing the value of the function. The generalization of optimization theory and techniques to other formulations constitutes a large ar

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Imma tetrope

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Imma tetrope

Imma tetrope is a moth in the family Immidae. It was described by Alexey Diakonoff in 1978. It is found in Nepal.[1] The wingspan is about 15 mm. The forewings are dark purplish fuscous, anteriorly more dull blackish fuscous, posteriorly slightly lighter brownish fuscous with a bronze gloss. A slightly outwards-oblique transverse erected-oval white discal spot is found just beyond and parallel to the closing vein, rounded on both ends, gently narrowed downwards. There is a small whitish inwards-oblique mark beyond two-thirds of the costa, with a metallic blue dot below it and a couple of similar dots is found below the costa halfway between the preceding and the apex and a close series of such dots is located before the termen. The hindwings are deep purplish fuscous, suffused with dark purple and with an ill-defined paler fuscous marginal streak from around the apex to the tornus, preceded by a narrower similar streak. There is also a narrow blue-metallic line, throughout edging a marginal streak anteriorly

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Moths described in 1978

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Immidae

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Domain Name System

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Domain Name System

The Domain Name System (DNS) is a hierarchical and decentralized naming system for computers, services, or other resources connected to the Internet or a private network. It associates various information with domain names assigned to each of the participating entities. Most prominently, it translates more readily memorized domain names to the numerical IP addresses needed for locating and identifying computer services and devices with the underlying network protocols. By providing a worldwide, distributed directory service, the Domain Name System has been an essential component of the functionality of the Internet since 1985. The Domain Name System delegates the responsibility of assigning domain names and mapping those names to Internet resources by designating authoritative name servers for each domain. Network administrators may delegate authority over sub-domains of their allocated name space to other name servers. This mechanism provides distributed and fault-tolerant service and was designed to avoid

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Domain name system

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Application layer protocols

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Callionima denticulata

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Callionima denticulata

Callionima denticulata is a species of moth in the family Sphingidae, which is known from Panama, Mexico, Costa Rica, Nicaragua, Bolivia, Peru and western Venezuela. It was originally described by Schaus as Calliomma denticulata, in 1895.[1] The wingspan is 59–72 mm. Adults are on wing year round in Costa Rica.[2] It is extremely similar to Callionima pan pan, but the forewing apex is strongly truncate, the outer margin strongly excavate below the apex and markedly dentate. The basal half of the forewing underside is distinctly orange, contrasting with the greyish-brown distal part. The hindwing upperside is as in Callionima pan pan, but the black anal spot is at least 1.5 mm wide. The larvae feed on Tabernaemontana alba and probably other Apocynaceae species. They are green with reddish orange spiracles and a longitudinal, dotted black line down the back and an orange, thick anal horn. References "Callionima denticulata (Schaus, 1895) sec CATE Sphingidae, 2009". Cate-sphingidae.org. Archived from the

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Sphingidae of South America

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New York State Route 40

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New York State Route 40

New York State Route 40 (NY 40) is a north–south state highway in eastern New York in the United States. It is 54.67 miles (87.98 km) long and runs from NY 7 in the city of Troy north to NY 22 in the town of Granville. NY 40 also passes through the villages of Schaghticoke and Argyle and enters the vicinity of the village of Greenwich. It intersects three east–west highways of note: NY 67 just outside Schaghticoke, NY 29 west of Greenwich, and NY 149 in the hamlet of Hartford. Incidentally, NY 40 has overlaps with all three routes. NY 40 originally extended south to East Greenbush and north to Comstock when it was assigned as part of the 1930 renumbering of state highways in New York. The route was truncated south to NY 149 in Hartford in the early 1940s and north to U.S. Route 4 in North Greenbush in the late 1950s. It was re-extended northward to its current northern terminus in the 1960s, but also truncated northward to its current southern terminus in the early 1970s. In 1980, ownership and maintenance o

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Former state highways in New York (state)

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Cluster decomposition theorem

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Cluster decomposition theorem

In physics, the cluster decomposition property is related to locality in quantum field theory. In a quantum field theory having this property, the vacuum expectation value of a product of many operators – each of them being either in region A or in region B where A and B are very separated – asymptotically equals the product of the expectation value of the product of the operators in A, times a similar factor from the region B. Consequently, sufficiently separated regions behave independently. Functional average of a number of field operator is called correlation function or correlator. So the spacelike asymptotic behaviour of truncated correlators consisting of field clusters determines how the strength of the correlations between the field degrees of freedom in these clusters changes as the distance between the clusters grows, and this behaviour is characterised by the cluster decomposition theorem.[1] If A 1 , … , A n {\displaystyle A_{1},\dots ,A_{n}} are n {\displaystyle n} operato

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Wave packet

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Wave packet

A wave packet without dispersion (real or imaginary part) A wave packet with dispersion In physics, a wave packet (or wave train) is a short "burst" or "envelope" of localized wave action that travels as a unit. A wave packet can be analyzed into, or can be synthesized from, an infinite set of component sinusoidal waves of different wavenumbers, with phases and amplitudes such that they interfere constructively only over a small region of space, and destructively elsewhere.[1] Each component wave function, and hence the wave packet, are solutions of a wave equation. Depending on the wave equation, the wave packet's profile may remain constant (no dispersion, see figure) or it may change (dispersion) while propagating. Quantum mechanics ascribes a special significance to the wave packet; it is interpreted as a probability amplitude, its norm squared describing the probability density that a particle or particles in a particular state will be measured to have a given position or momentum. The wave equation

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Gun barrel sequence

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Gun barrel sequence

The gun barrel sequence is the signature device featured in nearly every James Bond film.[1] Shot from the point of view of a presumed assassin, it features James Bond walking, turning, and then shooting directly at camera, causing blood to run down the screen. The visuals are usually accompanied by the "James Bond Theme", written by Monty Norman. Originally designed by Maurice Binder, the sequence has featured in every James Bond film produced by Eon Productions, and while retaining the same basic elements, has evolved noticeably throughout the series.[2] It is one of the most immediately recognisable elements of the franchise and has featured heavily in marketing material for the films and their spin-offs. The British media historian James Chapman suggests that the sequence is a significant part of the James Bond mythos because it "foregrounds the motif of looking, which is central to the spy genre."[3] Description In all but a couple of films, the sequence begins with a white dot blinking across the sc

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James Bond in film

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Great icosahedron

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Great icosahedron

Great icosahedron Type Kepler–Poinsot polyhedron Stellation core icosahedron Elements F = 20, E = 30V = 12 (χ = 2) Faces by sides 20{3} Schläfli symbol {3,5/2} Face configuration V(53)/2 Wythoff symbol 5/2 | 2 3 Coxeter diagram Symmetry group I, H, [5,3], (*532) References U, C, W Properties Regular nonconvex deltahedron (35)/2(Vertex figure) Great stellated dodecahedron(dual polyhedron) In geometry, the great icosahedron is one of four Kepler-Poinsot polyhedra (nonconvex regular polyhedra), with Schläfli symbol {3,5/2} and Coxeter-Dynkin diagram of . It is composed of 20 intersecting triangular faces, having five triangles meeting at each vertex in a pentagrammic sequence. The great icosahedron can be constructed analogously to the pentagram, its two-dimensional analogue, via the extension of the (n-1)-D simplex faces of the core nD polytope (equilateral triangles for the great icosahedron, and line segments for the pentagram) until the figure regains reg

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Minnesota State Highway 242

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Minnesota State Highway 242

Minnesota State Highway 242 was a 5.3-mile-long (8.5 km) highway in Minnesota. It connected U.S. Highway 10 and Minnesota State Highway 47 near Coon Rapids with Minnesota State Highway 65 in Blaine. It has been classified by the Metropolitan Council as a primary arterial street. Route description Highway 242 originally served as an east–west route between the cities of Anoka, Coon Rapids, and Blaine. The route was legally defined as Route 242 in the Minnesota Statutes.[4] History Highway 242 was authorized on July 1, 1949[1] and was paved when it was marked.[5] The highway used to run to downtown Anoka, but in 1979 it was truncated at its easternmost intersection with U.S. Highway 10.[6] On June 15, 2007, Highway 242 was transferred from the State of Minnesota to Anoka County maintenance. It is now an extension of County State Aid Highway (CSAH) 14.[3] Major intersections The entire route was in Anoka County. Location mi km Destinations Notes Anoka US 10 / US 169 US 169 Rum Riv

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County roads in Anoka County, Minnesota

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State highways in Minnesota

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Excommatica

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Excommatica

Excommatica is a genus of moth in the family Gelechiidae. It contains the species Excommatica compsotoma, which is found in Mozambique and Zimbabwe.[1][2] The wingspan is about 10 mm. The forewings are pale ochreous with an irregular blackish patch extending along the dorsum from near the base to near the tornus, widest before the middle of the wing, where it extends half across, the edge sinuate before and beyond this, narrow towards the posterior extremity, the apex truncate and followed by slight whitish suffusion. There is a broad blackish streak along the costa from before the middle to the apex, pointed anteriorly, cut by an oblique whitish strigula at two-thirds and a less oblique grey-whitish strigula at three-fourths, the lower edge between this and the apex semicircularly excavated. There is also an oval silvery-white spot on the middle of the termen containing an elongate black dot. The hindwings are grey, lighter and bluish-tinged anteriorly.[3] References funet.fi Afro Moths Ann. Tran

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Gelechiidae

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BBGKY hierarchy

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BBGKY hierarchy

In statistical physics, the BBGKY hierarchy (Bogoliubov–Born–Green–Kirkwood–Yvon hierarchy, sometimes called Bogoliubov hierarchy) is a set of equations describing the dynamics of a system of a large number of interacting particles. The equation for an s-particle distribution function (probability density function) in the BBGKY hierarchy includes the (s + 1)-particle distribution function thus forming a coupled chain of equations. This formal theoretic result is named after Bogoliubov, Born, Green, Kirkwood, and Yvon. Formulation The evolution of an N-particle system in absence of quantum fluctuations is given by the Liouville equation for the probability density function f N = f N ( q 1 … q N , p 1 … p N , t ) {\displaystyle f_{N}=f_{N}(\mathbf {q} _{1}\dots \mathbf {q} _{N},\mathbf {p} _{1}\dots \mathbf {p} _{N},t)} in 6N dimensional phase space (3 space and 3 momentum coordinates per particle) ∂ f N ∂ t + ∑ i = 1 N p i m ∂ f N

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Delta modulation

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Delta modulation

Principle of the delta PWM. The output signal (blue) is compared with the limits (green). The limits (green) correspond to the reference signal (red), offset by a given value. Every time the output signal reaches one of the limits, the PWM signal changes state. A delta modulation (DM or Δ-modulation) is an analog-to-digital and digital-to-analog signal conversion technique used for transmission of voice information where quality is not of primary importance. DM is the simplest form of differential pulse-code modulation (DPCM) where the difference between successive samples are encoded into n-bit data streams. In delta modulation, the transmitted data are reduced to a 1-bit data stream. Its main features are: The analog signal is approximated with a series of segments. Each segment of the approximated signal is compared to the preceding bits and the successive bits are determined by this comparison. Only the change of information is sent, that is, only an increase or decrease of the signal amplitude from

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Printf format string

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Printf format string

An example of the printf function. printf format string refers to a control parameter used by a class of functions in the input/output libraries of C and many other programming languages. The string is written in a simple template language: characters are usually copied literally into the function's output, but format specifiers, which start with a % character, indicate the location and method to translate a piece of data (such as a number) to characters. "printf" is the name of one of the main C output functions, and stands for "print formatted". printf format strings are complementary to scanf format strings, which provide formatted input (parsing). In both cases these provide simple functionality and fixed format compared to more sophisticated and flexible template engines or parsers, but are sufficient for many purposes. Many languages other than C copy the printf format string syntax closely or exactly in their own I/O functions. Mismatches between the format specifiers and type of the data can cause

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Taygete altivola

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Taygete altivola

Taygete altivola is a moth in the Autostichidae family. It was described by Meyrick in 1929. It is found in Peru.[1] The wingspan is about 12 mm. The forewings are grey-whitish with a dark grey basal patch somewhat mixed pale ochreous occupying one-fifth of the wing, the edge rather inwards-oblique from the costa. There is an elongate grey mark on the costa beyond this and a triangular dark grey blotch somewhat tinged ochreous on the costa rather beyond the middle reaching more than half across the wing, its apex truncate, some slight grey suffusion in the disc preceding this. The stigmata are small and black, the plical suffused yellowish, rather obliquely before the first discal. There is a small blackish dorsal spot beneath the second discal, and a blackish dot between these. The apical fifth is suffused grey and ochreous, with some dark fuscous scales, a blackish dash on the tornal edge, dark fuscous marks around the remainder of the edge. The hindwings are grey.[2] References funet Exot. Microle

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Symmocinae

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Moths described in 1929

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Antaeotricha praecisa

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Antaeotricha praecisa

Antaeotricha praecisa is a moth of the family Depressariidae. It is found in Brazil (Rio de Janeiro, São Paulo).[1] The wingspan is 20–25 mm. The forewings have a dark fuscous patch with purplish-leaden reflections and are irregularly mixed with blackish extending from the base of the costa along the dorsum to two-thirds, reaching two-thirds across the wing and posteriorly truncate, the angle edged with black. There are two irregular transverse fuscous shades beyond this, the first with the costal extremity obsolete or represented by a cloudy dot beneath the middle of the costa, the second sometimes reaching the costa at three-fourths. A third shade is indicated by a tornal mark and a small black costal spot. The hindwings are whitish-grey, in males with a subcostal pencil of long whitish hairs reaching from the base to the middle. The costal edge in males with a projection of grey scales before the middle.[2] References "Antaeotricha Zeller, 1854" at Markku Savela's Lepidoptera and Some Other Life Form

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Moths of Brazil

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Antaeotricha

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Moths described in 1912

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Srinivasa Ramanujan

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Srinivasa Ramanujan

Srinivasa Ramanujan FRS ([1] listen ; 22 December 1887 – 26 April 1920)[2] was an Indian mathematician who lived during the British Rule in India. Though he had almost no formal training in pure mathematics, he made substantial contributions to mathematical analysis, number theory, infinite series, and continued fractions, including solutions to mathematical problems then considered unsolvable. Ramanujan initially developed his own mathematical research in isolation: "He tried to interest the leading professional mathematicians in his work, but failed for the most part. What he had to show them was too novel, too unfamiliar, and additionally presented in unusual ways; they could not be bothered".[3] Seeking mathematicians who could better understand his work, in 1913 he began a postal partnership with the English mathematician G. H. Hardy at the University of Cambridge, England. Recognizing Ramanujan's work as extraordinary, Hardy arranged for him to travel to Cambridge. In his notes, Ramanujan had produced g

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Recipients of the Shanti Swarup Bhatnagar Award...

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Child prodigies

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CS1 Malayalam-language sources (ml)

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Singular integral operators on closed curves

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Singular integral operators on closed curves

In mathematics, singular integral operators on closed curves arise in problems in analysis, in particular complex analysis and harmonic analysis. The two main singular integral operators, the Hilbert transform and the Cauchy transform, can be defined for any smooth Jordan curve in the complex plane and are related by a simple algebraic formula. The Hilbert transform is an involution and the Cauchy transform an idempotent. The range of the Cauchy transform is the Hardy space of the bounded region enclosed by the Jordan curve. The theory for the original curve can be deduced from that on the unit circle, where, because of rotational symmetry, both operators are classical singular integral operators of convolution type. The Hilbert transform satisfies the jump relations of Plemelj and Sokhotski, which express the original function as the difference between the boundary values of holomorphic functions on the region and its complement. Singular integral operators have been studied on various classes of functions,

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Stationary-wave integrated Fourier transform spectrometry

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Stationary-wave integrated Fourier transform spectrometry

Stationary-wave integrated Fourier transform spectrometry (SWIFTS) is an analytical technique used for measuring the distribution of light across an optical spectrum. SWIFTS technology is based on a near-field Lippmann architecture. An optical signal is injected into a waveguide and ended by a mirror (true Lippman configuration). The input signal interferes with the reflected signal, creating a stationary wave. In a counter-propagative architecture, the two optical signals are injected at the opposite ends of the waveguide. The evanescent waves propagating within the waveguide are then sampled by optical probes. This results in an interferogram. A mathematical function known as a Lippmann transform, similar to a Fourier transform, is later used to give the spectrum of the light. History In 1891, at the Académie des Sciences in Paris, Gabriel Lippmann presented a colour photograph of the Sun's spectrum obtained with his new photographic plate.[1] Later, in 1894, he published an article on how his plate was

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Cantharidus marmoreus

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Cantharidus marmoreus

Cantharidus marmoreus is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.[2][3] Description The height of the shell attains 8 mm, its diameter 5 mm. The rather solid shell has an elongate-conical shape. It is imperforate, but with a groove and pit or even a slight perforation at the place of the umbilicus. It is whitish, longitudinally clouded with brown or pink, often showing white opaque scattered dots. The surface is polished. The sculpture consists of numerous broad flat smooth spirals, separated by impressed lines. There are seven of these flat spiral ribs on the upper surface of the body whorl, the peripheral one larger. The base of the shell has numerous concentric striae, and about 4 spaced, more impressed grooves. The spire is high with its lateral outlines nearly straight . There are about 8 whorls, each one a trifle convex, the last angular at the periphery. The base of the shell is a little convex. The aperture is quadrate. The columella is vertical and

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Animals described in 1868

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Cantharidus

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Vertical bar

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Vertical bar

The vertical bar ( | ) is a computer character and glyph with various uses in mathematics, computing, and typography. It has many names, often related to particular meanings: Sheffer stroke (in logic), verti-bar, vbar, stick, vertical line, vertical slash, bar, pike, or pipe, and several variants on these names. It is occasionally considered an allograph of broken bar (see below). Usage Mathematics The vertical bar is used as a mathematical symbol in numerous ways: absolute value: | x | {\displaystyle |x|} , read "the absolute value of x" cardinality: | S | {\displaystyle |S|} , read "the cardinality of the set S" conditional probability: P ( X | Y ) {\displaystyle P(X|Y)} , reads "the probability of X given Y" determinant: | A | {\displaystyle |A|} , read "the determinant of the matrix A". When the matrix entries are written out, the determinant is denoted by surrounding the matrix entries by vertical bars instead of the usual brackets or parentheses of the ma

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Dendrotriton xolocalcae

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Dendrotriton xolocalcae

Dendrotriton xolocalcae, commonly known as the Xolocalca bromeliad salamander or Xolocalco bromeliad salamander, is a species of salamander in the family Plethodontidae. It is endemic to Chiapas, Mexico, and only known from its type locality, Cerro Ovando, at an elevation of about 2,000 m (6,600 ft) asl.[1][3] The specific name xolocalcae is derived from the Indian name of Cerro Ovando, Xolocalco.[2] Description The holotype (sex unspecified) measures 37 mm (1.5 in) in snout–vent length and 56 mm (2.2 in) in total length. The body and head are flattened, and the head is much broader than the body. The hands and feet are large. Only the first finger and toe are webbed; the digits are broad and truncate. The tail is slender and attenuated. There are three distinct color patters: most specimens are mottled brownish-lavender above, with a black, triangular head marking. Some specimens have a pair of cream dorsolateral lines that start from the eyelid and continue back. The third variety has pinkish cream back a

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Amphibians described in 1941

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Taxa named by Edward Harrison Taylor

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Dendrotriton

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