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971.
972.
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   
973.
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   
974.
Hypothesized, on the basis of findings from several studies, that rejected children are more disruptive, aggressive, and socially inappropriate than are their classmates. Three groups of 39 rejected, 29 neglected, and 39 accepted children were randomly selected from 282 boys and 210 girls who were identified separately on the basis of sociometric scores for 492 children in Grades 3–6. The 3 groups were compared using multiple analysis of variance (MANOVA) on measures from 4 domains: peer behavioral attributions, teacher ratings, analog assertiveness task, and self-evaluation. Rejected Ss were clearly distinguished from their same-sex neglected and accepted classmates and were described by teachers and peers as aggressive, disruptive and inattentive. Neglected Ss were only marginally discriminable from same-sex accepted children. Neither neglected nor rejected Ss were differentiated from accepted Ss with respect to observed assertiveness and self-ratings of shyness, unhappiness, and feeling unaccepted. The results replicate previous findings for rejected children. Currently, there is not sufficient justification to consider the group of socially neglected children as a clinical category. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
975.
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   
976.
MetaModel is a user-friendly program for calculating steady-state fluxes and metabolite concentrations of metabolic systems on the IBM PC and compatible computers. For any steady state that is obtained, one can then calculate a matrix of elasticity coefficients at that steady state, or a matrix of control and response coefficients. It thus offers a simple way to calculate the control structure of a pathway: it provides not only an educational tool that allows the student to verify empirically the classic summation relationships of metabolic control analysis but also a research tool for addressing 'what if?' questions about the behaviour of metabolic systems. Results can not only be printed or stored in a file, but can also be written to a special file that can be read by popular spreadsheet programs, thereby giving access to rapid, flexible and powerful methods for subsequent analysis and plotting of these results.  相似文献   
977.
978.
979.
980.
A method for assessing health care technology that models the demand on the clinician's attention exerted by patients' data (diagnostic and therapeutic) can provide a means for simultaneously reducing the cost and improving the quality of health care. The attentional demand exerted by patients' data can be measured by the amount of uncertainty in the data. Uncertainty can be expressed mathematically by the concept of entropy in information theory.  相似文献   
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