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31.
The design of controlled-resistance loads for domestic induction heating applications using thin non-magnetic conductive layers is described. Thin metallic layers are fabricated using the phase vapour deposition technique. Such layers would enable vessels, the inductive behaviour of which was similar to those fabricated with conventional ferromagnetic bulk materials, to be manufactured. Optimum layer thickness is investigated using an analytical impedance model of the complete induction system 相似文献
32.
33.
A very simple algorithm for computing all k nearest neighbors in 2-D is presented. The method does not rely on complicated forms of tessellation, it only requires simple data binning for fast range searching. Its applications range from scattered data interpolation to reverse engineering. 相似文献
34.
The flow and fracture behavior of Be-Al alloys were determined in tension with different levels of superimposed pressure.
The Be-Al alloys were prepared by Brush Wellman, Inc. (Cleveland, OH) from prealloyed powders processed to either a hot isostatically
pressed (“hipped”) or cold isostatically pressed and extruded condition. Significant effects of pressure on both the flow
and ductility have been observed at room temperature, with implications on the formability of these materials. The effects
of changes in processing conditions and stress state on the flow and fracture behavior are summarized in addition to both
optical and scanning electron microscopy (SEM) examination of the fracture surfaces. Separate other studies on the alloy constituents
(e.g., Al and Be) are also reported. The results are also compared to previous works on monolithic materials and composites tested
with high pressure. 相似文献
35.
MS Oitzl ER de Kloet M Jo?ls W Schmid TJ Cole 《Canadian Metallurgical Quarterly》1997,9(11):2284-2296
Previous studies in rats using the Morris water maze suggested that the processing of spatial information is modulated by corticosteroid hormones through mineralocorticoid and glucocorticoid receptors in the hippocampus. Mineralocorticoid receptors appear to be involved in the modulation of explorative behaviour, while additional activation of glucocorticoid receptors facilitates the storage of information. In the present study we used the water maze task to examine spatial learning and memory in mice homozygous and heterozygous for a targeted disruption of the glucocorticoid receptor gene. Compared with wild-type controls, homozygous and heterozygous mice were impaired in the processing of spatial but not visual information. Homozygous mutants performed variably during training, without specific platform-directed search strategies. The spatial learning disability was partly compensated for by increased motor activity. The deficits were indicative of a dysfunction of glucocorticoid receptors as well as of mineralocorticoid receptors. Although the heterozygous mice performed similarly to wild-type mice with respect to latency to find the platform, their strategy was more similar to that of the homozygous mice. Glucocorticoid receptor-related long-term spatial memory was impaired. The increased behavioural reactivity of the heterozygous mice in the open field points to a more prominent mineralocorticoid receptor-mediated function. The findings indicate that (i) the glucocorticoid receptor is of critical importance for the control of spatial behavioural functions, and (ii) mineralocorticoid receptor-mediated effects on this behaviour require interaction with functional glucocorticoid receptors. Until the development of site-specific, inducible glucocorticoid receptor mutants, glucocorticoid receptor-knockout mice present the only animal model for the study of corticosteroid-mediated effects in the complete absence of a functional receptor. 相似文献
36.
The article presents a review of most important research results as well as opinions about the role and importance of body image disturbances in the development and the course of eating disorders. It also contains a review of definitions of body image, and techniques used in the evaluation of this type of disorders. 相似文献
37.
This paper describes how SWoRD (scaffolded writing and rewriting in the discipline), a web-based reciprocal peer review system, supports writing practice, particularly for large content courses in which writing is considered critical but not feasibly included. To help students gain content knowledge as well as writing and reviewing skills, SWoRD supports the whole cycle of writing, reviews, back-reviews, and rewriting by scaffolding the journal publication process as its authentic practice model. In addition, SWoRD includes algorithms that compute individual reviewer’s review accuracy, which is in turn used to support the various drawbacks of reciprocal peer reviews (e.g., variation in motivation or ability of reviewers). Finally, this paper describes an empirical evaluation showing that the SWoRD approach is effective in improving writing quality in content classes. 相似文献
38.
39.
Bourque Paul; Blanchard Louis; Saulnier Jo?l; Vézina Jean 《Canadian Metallurgical Quarterly》1992,24(1):118
Studied the relationship among age, physical health status, and psychic and somatic symptoms of depression among elderly adults. Human Ss: 318 male and female Canadian older adults (aged 65–102 yrs). Information on sociodemographic factors and health status was obtained using the Older American Research Scale, French version, by R. Lefran?ois et al (1988). A French version by P. Bourque and D. Beaudette (1982) of the Beck Depression Inventory was also used. The results were evaluated according to each S's sex, age, institutionalized residence status, and health status. Statistical tests were used. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
Interest has increased during recent years in using microcomputers for implementation of network reliability algorithms. There are indications that some implementations suffer severe restrictions imposed by such a computing environment, whereas some other results indicate otherwise. This brief note attempts to clarify the apparently contradictory conclusions that would be naturally drawn from recent papers that treat this subject. 相似文献