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81.
Various influence diagnostics in Multiple Discriminant Analysis can be found in the literature. Almost all of them are based
on the overall probability of misclassification. Two case-deletion diagnostics which evaluate the effect of the omission on
the linear functions which determine Fisher’s Linear Discriminant Rule are proposed in this paper. Both measures are based
on the L
2-norm: The first diagnostic is calculated from the data set and the second diagnostic is calculated in the minimum hypercube
which covers it. 相似文献
82.
A. D. Pogrebnyak M. V. Il’yashenko V. S. Kshnyakin V. V. Ponaryadov Sh. M. Ruzimov Yu. N. Tyurin 《Technical Physics Letters》2003,29(12):1028-1030
Chromium carbide-nickel coatings were deposited onto a technical grade copper substrate by means of a high-velocity plasma
jet of a plasmatron operating in specially selected regimes. An analysis of the coatings showed evidence of the formation
of a Ni-based solid solution, a complex chromium carbide (Cr7C3), and an fcc crystal phase with a lattice parameter of 3.614 Å. The surface of the coatings exhibits a characteristic relief
resulting from a dynamic interaction between melted and fused particles of the initial powder. The local hardness on some
areas of the surface and in depth of the coating reaches 66±4.5 HRC, while the coating adhesion strength varies from 25 to
300 MPa. 相似文献
83.
The nucleation of gas bubbles in extrusion foaming of high-pressure polyethylene is considered. Experiments show that undissolved gas microbubbles in the solution being foamed can have a significant effect on the number density of pores in the foam. A simple model for estimating the number density of supercritical nuclei is proposed. The effect of the time of mixing of gas and polymer in the extruder, the talc concentration, and the geometric characteristics of the nozzle on the number density of pores in the foam is analyzed. 相似文献
84.
85.
Jon T. Carter Paul E. Krajewski Ravi Verma 《JOM Journal of the Minerals, Metals and Materials Society》2008,60(11):77-81
The hot blow forming of magnesium sheet offers significant opportunity for forming complex, lightweight parts for automotive
applications. This paper characterizes the elevated-temperature formability of AZ31 magnesium sheet materials and the effect
of processing conditions on the performance of these materials. In addition, magnesium sheet application development at General
Motors Corporation is reviewed. 相似文献
86.
Toshihiko Hoshide Junpei Fujita 《Journal of Materials Engineering and Performance》2008,17(5):627-632
Strength of ground ceramics may be affected by residual stress as well as surface flaws induced by grinding. Strength prediction
for ground ceramics is convenient for mechanical design of ceramic components. In this article, a numerical procedure based
on fracture mechanics was proposed to estimate strength distribution of ground ceramics by considering grinding-induced residual
stress. Bending strength and residual stress of ground ceramics were measured for three grinding-conditions. By comparison
of simulated results with experimental ones, it was revealed that strength characteristics in experiments were well simulated
by using the proposed procedure. 相似文献
87.
88.
G. Mentzas 《欧洲信息系统杂志》1991,1(3):193-203
The purpose of this paper is to provide an analysis of the alternative modelling systems for office information systems. More specifically, we are interested in identifying the current research trends of merging office modelling ideas together with concepts that owe their origin to the object-oriented paradigm and to artificial intelligence. In this respect an office model is defined as encompassing three domains: passive office objects; dynamically defined and manipulated office procedures; and goal-directed office tasks. Following this definition we exploit the potential of using the object-oriented and knowledge representation techniques for modelling each of the three domains using evidence from real-world applications. 相似文献
89.
N. N. Belov Yu. A. Biryukov A. T. Roslyak N. T. Yugov S. A. Afanas’eva 《Theoretical Foundations of Chemical Engineering》2005,39(3):307-312
A new circulation pneumatic crusher capable of producing submicron powders of refractory materials is presented. A mathematical model is constructed for the dynamic breaking of ceramic macroparticles. This model allows the basic laws of shock-wave crushing in the circulation pneumatic apparatus to be analyzed.__________Translated from Teoreticheskie Osnovy Khimicheskoi Tekhnologii, Vol. 39, No. 3, 2005, pp. 327–333.Original Russian Text Copyright © 2005 by Belov, Biryukov, Roslyak, Yugov, Afanas’ev. 相似文献
90.
Zirconium(IV) tungstoiodophosphate has been synthesized under a variety of conditions. The most chemically and thermally stable
sample is prepared by adding a mixture of aqueous solutions of 0·5 mol L−1 sodium tungstate, potassium iodate and 1 mol L−1 orthophosphoric acid to aqueous solution of 0·1 mol L−1 zirconium(IV) oxychloride. Its ion exchange capacity for Na+ and K+ was found to be 2·20 and 2·35 meq g−1 dry exchanger, respectively. The material has been characterized on the basis of chemical composition, pH titration, Fourier
transform infrared spectroscopy (FTIR) and thermogravimetric analysis. The effect on the exchange capacity of drying the exchanger
at different temperatures has been studied. The analytical importance of the material has been established by quantitative
separation of Pb2+ from other metal ions. 相似文献