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McWayne Christine M.; Fantuzzo John W.; McDermott Paul A. 《Canadian Metallurgical Quarterly》2004,40(4):633
The present concurrent study combined developmental and ecological considerations to examine the unique contribution of multiple preschool competencies to an indicator of early academic success. Participants included 195 Head Start children from 32 classrooms representative of a large, urban Head Start program. Dimensional (variable-centered) analyses revealed 3 distinct classroom competency dimensions (i.e., General Classroom Competencies, Specific Approaches to Learning, and Interpersonal Classroom Behavioral Problems). The first 2 of these dimensions were found to be uniquely associated with early academic success. Findings from typological (person-centered) analyses supported the dimensional findings. Typological analyses revealed 7 profiles of classroom competency distinguished by high scores on the dimensions of General Competencies and Approaches to Learning, and these profiles were found to relate differentially to the indicator of early academic success. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Coarse filters for shape matching 总被引:3,自引:0,他引:3
Corney J. Rea H. Clark D. Pritchard J. Breaks M. Macleod R. 《Computer Graphics and Applications, IEEE》2002,22(3):65-74
This article describes the coarse shape filters that support the 3D, Internet-based search engine ShapeSifter, which aims to locate parts already in production that have a shape similar to a desired new part. The search engine analyzes the target model's shape characteristics and performs a similarity match on the database's contents. Our main challenge is identifying shape metrics that produce effective characterizations of 3D models for similarity comparison. We focus on using three novel convex hull-based indices to carry out a preliminary coarse filtering of candidates prior to more detailed analysis. We also describe the crucial role played by two databases of benchmark objects. Unlike other shape-matching systems, we chose ShapeSifter's architecture (multistep query), 3D representation (triangulated mesh), and implementation (Java3D) to allow deployment online once it matures 相似文献
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Model-driven development - Guest editor's introduction 总被引:1,自引:0,他引:1
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Graduates of clinical training programs were surveyed to determine the degree to which they have found various graduate school experiences useful in their professional work. Samples of academic clinical psychologists and practicing clinical psychologists reported time allocation and preference for various professional activities, perceived usefulness of various theoretical orientations, and the influence on their current professional work of 19 different graduate training topics. Results suggest that where differences exist, academic clinical psychologists are generally more satisfied with Boulder-model-inspired scientific training than are clinical practitioners. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The literature provides little information on high-speed, high-normal-load, plain linear bearings, although the case for two rigid surfaces in relative linear motion can readily be solved by assuming squeeze action resistance. A new genus of internal combustion engines based on the Stiller-Smith mechanism incorporates connecting rods constrained by linear bearings, with the central normal load on the rod restricted by an oil film. A general analysis takes into account the bending of the rod, when the distributed oil film pressure resists the distributed load on the elastic rod. Design charts result that yield the dimensionless velocity at which the rod sinks in the oil as a function of the dimensionless load and the bearing clearance, and predict the deflection of the beam. The rod clearance history simulations for the Stiller-Smith engine compare favourably with computations for the rigid beam, confirming the analysis technique. 相似文献
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EJ Clark 《Canadian Metallurgical Quarterly》1997,5(4):252-254
A method has been developed for the simultaneous analysis of the isomeric N-acetyl-S-(dichlorophenyl)cysteines (also known as dichlorophenylmercapturic acids, DCPMAs) in urine. This procedure allows the determination of 2,3- and 3,4-DCPMAs at the concentrations expected in the urine samples of employees occupationally exposed to 1,2-dichlorobenzene (1,2-DCB). The results of a 1,2-DCB exposure study under standardized conditions show a first-order kinetic for the excretion of DCPMAs, as well as acceptable linear correlations between the urinary concentrations of DCPMAs and the amount of inhaled 1,2-DCB. It therefore seems it would be possible to derive a biological tolerance value for 1,2-DCB based on isomeric DCPMAs as analytical parameters. 相似文献
8.
We have studied the inhibitory action of long- and short-chain fatty acids on hepatic glucose utilization in hepatocytes isolated from fasted rats. The rates of hepatic glucose phosphorylation and glycolysis were determined from the tritiated products of [2-3H] and [6-3H]glucose metabolism, respectively. The difference between these was taken as an estimate of the 'cycling' between glucose and glucose-6-phosphate. In the presence of 40 mM glucose this cycling was estimated at 0.68 mumol/min/g wet wt. Glucose phosphorylation was unaffected during palmitate and hexanoate oxidation to ketone bodies but glycolysis was inhibited. The rate of glucose cycling was increased during this phase to 1.25 mumol/min/g. Following the complete metabolism of the fatty acids, glycolysis was reinstated and cycling rates returned to control levels. Hepatic glucose cycling appears to be an important component of the glucose/fatty acid cycle. 相似文献
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We study the topological rigidity of affine semigroups of algebraic actions. In the first part of the paper we given an algebraic condition for rigidity that unifies previous rigidity results and we settle an old question of Walters. In the second part we study a generalized notion of the rigidity of hyperbolic actions. 相似文献