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Signature (other)
A signature is a hand-written, possibly stylized, version of someone's name, which may be used to confirm the person's identity. The writer of a signature is a signatory or signer. Signature or signatory may also refer to: Businesses and organizations * Signature (charity), trading name of UK-based Council for the Advancement of Communication for Deaf People (CACDP) * Signature (whisky), a brand of Indian whisky * ''Signature'', a brand of the clothing company Levi Strauss & Co. * Signature Books, a publisher of Mormon works * Signature Digital Menus, a company specializing in the provision of digital menu boards * Signature Flight Support, a British fixed-base operator * Signatures Restaurant, a restaurant formerly owned by Washington lobbyist Jack Abramoff * Signature School, a charter school in Evansville, Indiana spanning grades 9–12 * Signature Team, a French motor racing team * Signature Theatres, a movie theatre chain in California, Hawaii, and Montana operated by R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signatures
A signature (; from la, signare, "to sign") is a handwritten (and often stylized) depiction of someone's name, nickname, or even a simple "X" or other mark that a person writes on documents as a proof of identity and intent. The writer of a signature is a signatory or signer. Similar to a handwritten signature, a signature work describes the work as readily identifying its creator. A signature may be confused with an autograph, which is chiefly an artistic signature. This can lead to confusion when people have both an autograph and signature and as such some people in the public eye keep their signatures private whilst fully publishing their autograph. Function and types The traditional function of a signature is to permanently affix to a document a person's uniquely personal, undeniable self-identification as physical evidence of that person's personal witness and certification of the content of all, or a specified part, of the document. For example, the role of a signatu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Signature
A digital signature is a mathematical scheme for verifying the authenticity of digital messages or documents. A valid digital signature, where the prerequisites are satisfied, gives a recipient very high confidence that the message was created by a known sender ( authenticity), and that the message was not altered in transit ( integrity). Digital signatures are a standard element of most cryptographic protocol suites, and are commonly used for software distribution, financial transactions, contract management software, and in other cases where it is important to detect forgery or tampering. Digital signatures are often used to implement electronic signatures, which includes any electronic data that carries the intent of a signature, but not all electronic signatures use digital signatures. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signature (Moya Brennan Album)
''Signature'' is a music album by Irish musician Moya Brennan. This is her seventh solo album to be released. It was released on the 9 October 2006 in Ireland, the UK and the Netherlands. The worldwide release was scheduled for early 2007, but was temporarily delayed until 25 September 2007. Release Announcement from her official site: ''Sunday, 16 July 2006'' "In the last few days Moya has completed the recording and mixing of her new album entitled Signature. Release is planned in Europe for late September but check back here for release dates in specific places. We can now reveal the track listing for the album (and we anticipate that some of the titles will give rise to discussion!)" Snip from her official website on 'Signature' Signature looks back over a life less ordinary and portrays Moya's experiences through a collection of twelve superb tracks. Musically sharp and finely tuned, the album cleverly treads a fine line between the contemporary and the traditional whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Key Signature
In Western musical notation, a key signature is a set of sharp (), flat (), or rarely, natural () symbols placed on the staff at the beginning of a section of music. The initial key signature in a piece is placed immediately after the clef at the beginning of the first line. If the piece contains a section in a different key, the new key signature is placed at the beginning of that section. In a key signature, a sharp or flat symbol on a line or space of the staff indicates that the note represented by that line or space is to be played a semitone higher (sharp) or lower (flat) than it would otherwise be played. This applies through the end of the piece or until another key signature is indicated. Each symbol applies to all notes in the same pitch class—for example, a flat on the third line of the treble staff (as in the diagram) indicates that all notes appearing as Bs are played as B-flats. This convention was not universal until the late Baroque and early Classical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prime Signature
In mathematics, the prime signature of a number is the multiset of (nonzero) exponents of its prime factorization. The prime signature of a number having prime factorization p_1^p_2^ \dots p_n^ is the multiset \left \. For example, all prime numbers have a prime signature of , the squares of primes have a prime signature of , the products of 2 distinct primes have a prime signature of and the products of a square of a prime and a different prime (e.g. 12, 18, 20, ...) have a prime signature of . Properties The divisor function τ(''n''), the Möbius function ''μ''(''n''), the number of distinct prime divisors ω(''n'') of ''n'', the number of prime divisors Ω(''n'') of ''n'', the indicator function of the squarefree integers, and many other important functions in number theory, are functions of the prime signature of ''n''. In particular, τ(''n'') equals the product of the incremented by 1 exponents from the prime signature of ''n''. For example, 20 has prime signature ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signature Of A Knot
The signature of a knot is a topological invariant in knot theory. It may be computed from the Seifert surface. Given a knot ''K'' in the 3-sphere, it has a Seifert surface ''S'' whose boundary is ''K''. The Seifert form of ''S'' is the pairing \phi : H_1(S) \times H_1(S) \to \mathbb Z given by taking the linking number \operatorname(a^+,b^-) where a, b \in H_1(S) and a^+, b^- indicate the translates of ''a'' and ''b'' respectively in the positive and negative directions of the normal bundle to ''S''. Given a basis b_1,...,b_ for H_1(S) (where ''g'' is the genus of the surface) the Seifert form can be represented as a ''2g''-by-''2g'' Seifert matrix ''V'', V_=\phi(b_i,b_j). The signature of the matrix V+V^t, thought of as a symmetric bilinear form, is the signature of the knot ''K''. Slice knots are known to have zero signature. The Alexander module formulation Knot signatures can also be defined in terms of the Alexander module of the knot complement. Let X be the universa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signature (topology)
In the field of topology, the signature is an integer invariant which is defined for an oriented manifold ''M'' of dimension divisible by four. This invariant of a manifold has been studied in detail, starting with Rokhlin's theorem for 4-manifolds, and Hirzebruch signature theorem. Definition Given a connected and oriented manifold ''M'' of dimension 4''k'', the cup product gives rise to a quadratic form ''Q'' on the 'middle' real cohomology group :H^(M,\mathbf). The basic identity for the cup product :\alpha^p \smile \beta^q = (-1)^(\beta^q \smile \alpha^p) shows that with ''p'' = ''q'' = 2''k'' the product is symmetric. It takes values in :H^(M,\mathbf). If we assume also that ''M'' is compact, Poincaré duality identifies this with :H^(M,\mathbf) which can be identified with \mathbf. Therefore the cup product, under these hypotheses, does give rise to a symmetric bilinear form on ''H''2''k''(''M'',''R''); and therefore to a quadratic form ''Q''. The form ''Q'' is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metric Signature
In mathematics, the signature of a metric tensor ''g'' (or equivalently, a real quadratic form thought of as a real symmetric bilinear form on a finite-dimensional vector space) is the number (counted with multiplicity) of positive, negative and zero eigenvalues of the real symmetric matrix of the metric tensor with respect to a basis. In relativistic physics, the ''v'' represents the time or virtual dimension, and the ''p'' for the space and physical dimension. Alternatively, it can be defined as the dimensions of a maximal positive and null subspace. By Sylvester's law of inertia these numbers do not depend on the choice of basis. The signature thus classifies the metric up to a choice of basis. The signature is often denoted by a pair of integers implying ''r''= 0, or as an explicit list of signs of eigenvalues such as or for the signatures and , respectively. The signature is said to be indefinite or mixed if both ''v'' and ''p'' are nonzero, and degenerate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadratic Form
In mathematics, a quadratic form is a polynomial with terms all of degree two ("form" is another name for a homogeneous polynomial). For example, :4x^2 + 2xy - 3y^2 is a quadratic form in the variables and . The coefficients usually belong to a fixed field , such as the real or complex numbers, and one speaks of a quadratic form over . If K=\mathbb R, and the quadratic form takes zero only when all variables are simultaneously zero, then it is a definite quadratic form, otherwise it is an isotropic quadratic form. Quadratic forms occupy a central place in various branches of mathematics, including number theory, linear algebra, group theory (orthogonal group), differential geometry ( Riemannian metric, second fundamental form), differential topology ( intersection forms of four-manifolds), and Lie theory (the Killing form). Quadratic forms are not to be confused with a quadratic equation, which has only one variable and includes terms of degree two or less. A quadra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signature (permutation)
In mathematics, when ''X'' is a finite set with at least two elements, the permutations of ''X'' (i.e. the bijective functions from ''X'' to ''X'') fall into two classes of equal size: the even permutations and the odd permutations. If any total ordering of ''X'' is fixed, the parity (oddness or evenness) of a permutation \sigma of ''X'' can be defined as the parity of the number of inversions for ''σ'', i.e., of pairs of elements ''x'', ''y'' of ''X'' such that and . The sign, signature, or signum of a permutation ''σ'' is denoted sgn(''σ'') and defined as +1 if ''σ'' is even and −1 if ''σ'' is odd. The signature defines the alternating character of the symmetric group S''n''. Another notation for the sign of a permutation is given by the more general Levi-Civita symbol (''ε''''σ''), which is defined for all maps from ''X'' to ''X'', and has value zero for non-bijective maps. The sign of a permutation can be explicitly expressed as : where ''N''(''σ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signature (logic)
In logic, especially mathematical logic, a signature lists and describes the non-logical symbols of a formal language. In universal algebra, a signature lists the operations that characterize an algebraic structure. In model theory, signatures are used for both purposes. They are rarely made explicit in more philosophical treatments of logic. Definition Formally, a (single-sorted) signature can be defined as a 4-tuple , where ''S''func and ''S''rel are disjoint sets not containing any other basic logical symbols, called respectively * ''function symbols'' (examples: +, ×, 0, 1), * ''relation symbols'' or ''predicates'' (examples: ≤, ∈), * ''constant symbols'' (examples: 0, 1), and a function ar: ''S''func \cup ''S''rel → \mathbb N which assigns a natural number called ''arity'' to every function or relation symbol. A function or relation symbol is called ''n''-ary if its arity is ''n''. Some authors define a nullary (0-ary) function symbol as ''constant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XML Signature
XML Signature (also called ''XMLDSig'', ''XML-DSig'', ''XML-Sig'') defines an XML syntax for digital signatures and is defined in the W3C recommendationbr>XML Signature Syntax and Processing Functionally, it has much in common with PKCS #7 but is more extensible and geared towards signing XML documents. It is used by various Web technologies such as SOAP, SAML, and others. XML signatures can be used to sign data–a resource–of any type, typically XML documents, but anything that is accessible via a URL can be signed. An XML signature used to sign a resource outside its containing XML document is called a detached signature; if it is used to sign some part of its containing document, it is called an enveloped signature; if it contains the signed data within itself it is called an enveloping signature. Structure An XML Signature consists of a Signature element in the http://www.w3.org/2000/09/xmldsig# namespace. The basic structure is as follows: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
