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β (other)
β is the Unicode character "circled minus" (U+2296). β is also known as the Plimsoll symbol. β may refer to: * Symmetric difference, the set of elements which are in either of two sets but not in their intersection * Erosion (morphology), one of the fundamental operations in morphological image processing * A function for reversal and rotation in the APL programming language * Symbol for the Escape character in ISO 2047 * Used to designate a thermodynamic quantity in the Standard state in chemistry * Part of the notation for Standard enthalpy of reaction, as in Ξ''H''βreaction See also *Celtic cross *Coptic cross * Cross symbol *Theta *Γ (other) *Circled plus (other) * ⦡ (U+29B5, CIRCLE WITH HORIZONTAL BAR) * Mathematical Operators (Unicode block) Mathematical Operators is a Unicode block containing characters for mathematical, logical, and set notation. Notably absent are the plus sign (+), greater than sign (>) and less than sign (<), due ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plimsoll Symbol
The load line, also known as Plimsoll line, indicates the legal limit to which a ship may be loaded for specific water types and temperatures in order to safely maintain buoyancy, particularly with regard to the hazard of waves. The load line is a waterline that corresponds to the maximum draft of the ship, thus yet another name, load waterline. Varying water temperatures will affect a ship's draft, because warm water is less dense than cold water, providing less buoyancy. In the same way, fresh water is less dense than salinated or seawater, with a similar lessening effect upon buoyancy. The rules for international load lines are defined by the International Convention on Load Lines from 1966. For inland water transport regional, national or local rules apply. Load lines are indicated by special markings on the hull. The marking for the main load line, the summer load line, is called load line mark or Plimsoll mark (positioned amidships), the marks for other conditions are n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symmetric Difference
In mathematics, the symmetric difference of two sets, also known as the disjunctive union and set sum, is the set of elements which are in either of the sets, but not in their intersection. For example, the symmetric difference of the sets \ and \ is \. The symmetric difference of the sets ''A'' and ''B'' is commonly denoted by A \operatorname\Delta B (alternatively, A \operatorname\vartriangle B), A \oplus B, or A \ominus B. It can be viewed as a form of addition modulo 2. The power set of any set becomes an abelian group under the operation of symmetric difference, with the empty set as the neutral element of the group and every element in this group being its own inverse. The power set of any set becomes a Boolean ring, with symmetric difference as the addition of the ring and intersection as the multiplication of the ring. Properties The symmetric difference is equivalent to the union of both relative complements, that is: :A\, \Delta\,B = \left(A \setminus B\ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erosion (morphology)
Erosion (usually represented by β) is one of two fundamental operations (the other being dilation) in morphological image processing from which all other morphological operations are based. It was originally defined for binary images, later being extended to grayscale images, and subsequently to complete lattices. The erosion operation usually uses a structuring element for probing and reducing the shapes contained in the input image. Binary erosion In binary morphology, an image is viewed as a subset of a Euclidean space \mathbb^d or the integer grid \mathbb^d, for some dimension ''d''. The basic idea in binary morphology is to probe an image with a simple, pre-defined shape, drawing conclusions on how this shape fits or misses the shapes in the image. This simple "probe" is called structuring element, and is itself a binary image (i.e., a subset of the space or grid). Let ''E'' be a Euclidean space or an integer grid, and ''A'' a binary image in ''E''. The erosion of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
APL (programming Language)
APL (named after the book ''A Programming Language'') is a programming language developed in the 1960s by Kenneth E. Iverson. Its central datatype is the multidimensional array. It uses a large range of special graphic symbols to represent most functions and operators, leading to very concise code. It has been an important influence on the development of concept modeling, spreadsheets, functional programming, and computer math packages. It has also inspired several other programming languages. History Mathematical notation A mathematical notation for manipulating arrays was developed by Kenneth E. Iverson, starting in 1957 at Harvard University. In 1960, he began work for IBM where he developed this notation with Adin Falkoff and published it in his book ''A Programming Language'' in 1962. The preface states its premise: This notation was used inside IBM for short research reports on computer systems, such as the Burroughs B5000 and its stack mechanism when stack m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Escape Character
In computing and telecommunications, an escape character is a character that invokes an alternative interpretation on the following characters in a character sequence. An escape character is a particular case of metacharacters. Generally, the judgement of whether something is an escape character or not depends on the context. In the telecommunications field, escape characters are used to indicate that the following characters are encoded differently. This is used to alter control characters that would otherwise be noticed and acted on by the underlying telecommunications hardware, such as illegal characters. In this context, the use of escape characters is often referred to as quoting. Definition An escape character may not have its own meaning, so all escape sequences are of two or more characters. Escape characters are part of the syntax for many programming languages, data formats, and communication protocols. For a given alphabet an escape character's purpose is to star ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISO 2047
ISO 2047 (Information processing – Graphical representations for the control characters of the 7-bit coded character set) is a standard for graphical representation of the control characters for debugging purposes, such as may be found in the character generator of a computer terminal; it also establishes a two-letter abbreviation of each control character. The graphics and two-letter codes are essentially unchanged from the 1968 European standard ECMA-17 (withdrawn) and the 1973 American standard ANSI X3.32-1973. It became an ISO standard in 1975. It is also standardized as GB/T 3911-1983 in China, as KS X 1010 in Korea (formerly KS C 5713), and was enacted in Japan as "graphical representation of information exchange capabilities for character" JIS X 0209:1976 (former JIS C 6227) (abolished January 20, 2010). While the ISO/IEC 646 three-letter abbreviations (such as "ESC"), or caret notation Caret notation is a notation for control characters in ASCII. The notation ass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard State
The standard state of a material (pure substance, mixture or solution) is a reference point used to calculate its properties under different conditions. A degree sign (Β°) or a superscript ⦡ symbol (⦡) is used to designate a thermodynamic quantity in the standard state, such as change in enthalpy (Ξ''H''Β°), change in entropy (Ξ''S''Β°), or change in Gibbs free energy (Ξ''G''Β°). The degree symbol has become widespread, although the Plimsoll is recommended in standards, see discussion about typesetting below. In principle, the choice of standard state is arbitrary, although the International Union of Pure and Applied Chemistry (IUPAC) recommends a conventional set of standard states for general use. The standard state should not be confused with standard temperature and pressure (STP) for gases, nor with the standard solutions used in analytical chemistry. STP is commonly used for calculations involving gases that approximate an ideal gas, whereas standard state condit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard Enthalpy Of Reaction
The standard enthalpy of reaction (denoted \Delta H_^\ominus) for a chemical reaction is the difference between total product and total reactant molar enthalpies, calculated for substances in their standard states. The value can be approximately interpreted in terms of the total of the chemical bond energies for bonds broken and bonds formed. For a generic chemical reaction :\nu_ \text + \nu_ \text ~+ ~... \rightarrow \nu_ \text + \nu_ \text ~+ ~... the standard enthalpy of reaction \Delta H_^\ominus is related to the standard enthalpy of formation \Delta_ H^\ominus values of the reactants and products by the following equation: : \Delta H_^\ominus = \sum_ \nu_p\Delta_ H_^ - \sum_ \nu_r\Delta_ H_^ In this equation, \nu_i are the stoichiometric coefficients of each product and reactant. The standard enthalpy of formation, which has been determined for a vast number of substances, is the change of enthalpy during the formation of 1 mole of the substance from its constituen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Celtic Cross
upright 0.75 , A Celtic cross symbol The Celtic cross is a form of ringed cross, a Christian cross featuring a nimbus or ring, that emerged in the British Isles and Western Europe in the Early Middle Ages. It became widespread through its use in the high crosses erected across the British Isles, especially in regions evangelised by Hiberno-Scottish missionaries, from the ninth through the 12th centuries. A staple of Insular art, the Celtic cross is essentially a Latin cross with a nimbus surrounding the intersection of the arms and stem. Scholars have debated its exact origins, but it is related to earlier crosses featuring rings. The form gained new popularity during the Celtic Revival of the 19th century; the name "Celtic cross" is a convention dating from that time. The shape, usually decorated with interlace and other motifs from Insular art, became popular for funerary monuments and other uses, and has remained so, spreading well beyond Ireland. Early history ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coptic Cross
The Coptic cross is any of a number of Christian cross variants associated in some way with Coptic Christians. Typical form The typical form of the "Coptic cross" used in the Coptic Church is made up of two bold lines of equal length that intersect at the middle at right angles. Each line terminates in three points, representing the Trinity of the Father, the Son, and the Holy Spirit. Altogether, the cross has 12 points symbolizing the Apostles, whose mission was to spread the Gospel message throughout the world. This form of Coptic cross is widely used in the Coptic church and the Ethiopian and Eritrean churches, and so this form of the cross may also be called the "Ethiopian cross" or "Axum cross". Bertran de la Farge dates it to the 4th century and cites it as a predecessor of the Occitan cross. History and variation Old Coptic crosses often incorporate a circle, as in the form called a "Coptic cross" by Rudolf Koch in his ''The Book of Signs'' (1933). Sometimes th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cross Symbol
A cross is a religious symbol consisting of two intersecting lines, usually perpendicular to each other. The lines usually run vertically and horizontally. A cross of oblique lines, in the shape of the Latin letter X, is termed a saltire in heraldic terminology. The cross shape has been widely officially recognized as an absolute and exclusive religious symbol of Christianity from an early period in that religion's history.''Christianity: an introduction'' by Alister E. McGrath 2006 pages 321-323 Before then, it was used as a religious or cultural symbol throughout , in |
