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Canonical processes of semantically annotated media production 总被引:1,自引:1,他引:0
Lynda Hardman Željko Obrenović Frank Nack Brigitte Kerhervé Kurt Piersol 《Multimedia Systems》2008,14(6):327-340
134.
An algorithm is presented for a common induction problem, the specialization of overty general concepts. A concept is too general when it matches a negative example. The particular case addressed here assumes that concepts are represented as conjunctions of positive literals, that specialization is performed by conjoining literals to the overly general concept, and that the resulting specializations are to be as general as possible. Although the problem is NP-hard, there exists an algorithm, based on manipulation of bit vectors, that has provided good performance in practice. 相似文献
135.
The effect of NaCl and SiO2 on the evolution of SO2 and SO3 from Na2SO4 at 850°C has been studied by mass spectrometry. NaCl lowers the melting point of Na2SO4 and increases SO2 evolution. The evolution of SO3 appears to result from a chemical reaction between Na2SO4 and SiO2. 相似文献
136.
The metal flow in a rod extrusion is theoretically discussed in relation to a frictional condition, strain hardening and strain rate hardening. An existing rigid plastic FEM-program was modified in order to take a rate sensitivity of a material into consideration through a constitutive equation of the form. An interfatial friction was incorporated by a constant Coulomb-frictional coefficient. When the frictional coefficient is smaller than 0.1, a large effect of the friction does not appear. The larger the n-value is, the stronger the distortion of the grid in a billet becomes even under small frictional resistance. The effect of the m-value is similar qualitatively to that of the n-value. When the rate sensitive material is extruded at very low punch speed under large frictional resistance, the material is strained very irregularly all over the billet at an early stage. 相似文献
137.
In principle, the version space approach can be applied to any induction problem. However, in some cases the representation language for generalizations is so powerful that (1) some of the update functions for the version space are not effectively computable, and (2) the version space contains infinitely many generalizations. The class of context-free grammars is a simple representation that exhibits these problems. This paper presents an algorithm that solves both problems for this domain. Given a sequence of strings, the algorithm incrementally constructs a data structure that has nearly all the beneficial properties of a version space. The algorithm is fast enough to solve small induction problems completely, and it serves as a framework for biases that permit the solution of larger problems heuristically. The same basic approach may be applied to representations that include context-free grammars as special cases, such as And-Or graphs, production systems, and Horn clauses. 相似文献
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139.
A brief introduction describes the main differences between homo, and copolymer polyacetals and their main degradation mechanisms. A short overview describes the importance of stabilization and the necessity of using antioxidants and costabilizers during manufacturing, processing and end use of polyoxymethylene(polyacetals). Various stabilizer systems are presented and studies on the interaction of antioxidants with costabilizers added. The criteria for testing the performance of these additives are discussed and demonstrated by many examples. In a second part the increasing importance of light stabilized polyacetal is mentioned and investigations on the performance of light stabilizer systems are highlighted. 相似文献
140.