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83.
A general structure of a linguistic classifier wherein sub-subclassifiers are the building blocks is suggested. Some properties of these sub-subclassifiers are proposed and proved. The physical significances of these properties are explored and it is shown that a condensed measure of belongingness of patterns to any class can be obtained which can conveniently be used for forming classification rules.  相似文献   
84.
报道用一步酸化法制得四种未见报道的1:10系列镧系钼钒杂多配合物K7H8LnMo4V6P36.xH2O(Ln=La,Ce,Pr,Nd)。提示元素分析,红外光谱,紫外光谱,X射线粉末衍射及差热-热重分析结果讨论了它们的结构及性质。  相似文献   
85.
The pure Ferroaluminophosphate molecular sieve(FAPO-5) was synthesized by hydrothermal crystallization. The crystal structure of FAPO-5 was studied via XRD, electron probe energy dispersion analysis, Mossbauer spectroscopy, EPR, XPS and IR, the parameters of unit cell and chemical composition of FAPO-5 were determined. The result has that the structure of FAPO-5 is AlPO -5 type and Fe2+ Fe3+ are incorporated into the framework of FAPO-5 molecular sieve. In addition, the chemical state of iron in FAPO-5 molecular sieve were studied and the adsorption properties, surface acidity and thermal stability were also investigated.  相似文献   
86.
The definition of random polytope adopted in this paper restricts consideration to those probability measures satisfying two properties. First, the measure must induce an absolutely continuous distribution over the positions of the bounding hyperplanes of the random polytope; and second, it must result in every point in the space being equally as likely as any other point of lying within the random polytope. An efficient Monte Carlo method for their computer generation is presented together with analytical formulas characterizing their aggregate properties. In particular, it is shown that the expected number of extreme points for such random polytopes increases monotonically in the number of constraints to the limiting case of a polytope topologically equivalent to a hypercube. The implied upper bound of 2 n wheren is the dimensionality of the space is significantly less than McMullen's attainable bound on the maximal number of vertices even for a moderate number of constraints.  相似文献   
87.
For an insurance company, effective risk management requires an appropriate measurement of the risk associated with an insurance portfolio. The objective of the present paper is to study properties of ruin-based risk measures defined within discrete-time risk models under a different perspective at the frontier of the theory of risk measures and ruin theory. Ruin theory is a convenient framework to assess the riskiness of an insurance business. We present and examine desirable properties of ruin-based risk measures. Applications within the classical discrete-time risk model and extensions allowing temporal dependence are investigated. The impact of the temporal dependence on ruin-based risk measures within those different risk models is also studied. We discuss capital allocation based on Euler’s principle for homogeneous and subadditive ruin-based risk measures.  相似文献   
88.
因为酞菁在信息、医疗、化工等众多领域有很广泛的应用,所以近百年来一直是科学家研究的热点课题.本文首次对一系列氮杂金属酞菁谱图性质研究,这些酞菁是氮杂酞菁铜、氮杂酞菁锌、氮杂酞菁钴、氮杂酞菁镍和氮杂酞菁汞,这5种氮杂金属酞菁的红外光谱图性质进行研究与比较.这些原因主要和中心配位为金属原子不同引起的.  相似文献   
89.

The equations of state and phase stability of calcium chalcogenides, CaS, CaSe and CaTe are investigated via first principles theoretical calculations. We report results of the structural properties of these compounds in the B1(NaCl) and the B2(CsCl) phases, the theoretical transition pressure and the volumes compression ratio. For CaTe we investigate the possible existence of an intermediate phase between the B1 and the B2 structure.  相似文献   
90.
The observation of optical second harmonic generation (SHG) from wetspun films of Na-DNA is reported. The SHG signal is stronger at a relative humidity of 92% (corresponding to the B conformation of Na-DNA) than at low humidity of -33% (corresponding to a disordered conformation of Na-DNA). The strength of the SHG signal is also dependent on the orientation of the incident laser beam polarization with respect to the DNA helical axes.  相似文献   
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