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951.
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使用Rieter公司的Com4并股线纺纱方法纺制的天丝纱能够满足生产精致的印度莎丽服的高要求。从许多方面来说,这种莎丽服与采用100%丝织成的传统莎丽服性能相当,但从纤维与纱线的加工成本看,比丝制莎丽服更加经济。 相似文献
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Tested the hypothesis that endogenous opioids are involved in the extinction of phobic fear through exposure in vivo. 48 spider phobics participated in a 2-hr therapist-directed exposure in vivo treatment. 16 Ss were assigned to placebo, 16 to a low dose of naltrexone, and 16 to a high dose of naltrexone. Before intervention, after treatment, and at a 1-wk follow-up test, self-report, physiological, and behavioral measures of phobic fear were completed. At 1-wk follow-up, naltrexone was significantly related, in a dose-dependent way, to a greater relapse on avoidance measures but not on emotional, cognitive, and physiological measures. Endogenous opioids may be specifically involved in the extinction of avoidance behavior but not in the extinction of all aspects of phobic fear. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
958.
Klaus-Peter Adlassnig Harald Leitich Gernot Kolarz 《Expert systems with applications》1993,6(4):441-448
-2/
is a medical expert system developed to assist in the differential diagnosis of rheumatic diseases. Based on fuzzy set theory and fuzzy logic, it supports the formalization of vague and uncertain medical information (i.e., medical entities and relationships between them) and draws justifiable conclusions from these imprecise data. Given a patient's finding patter,
-2 provides confirmed and excluded diagnoses, diagnostic hypotheses, and suggestions for further examinations. The knowledge base of
-2 has been designed to contain simple finding/disease relationships as well as diagnostic rules of high complexity to confirm or hypothesize disease. We shall present results obtained with 300 clinical cases from a hospital for rheumatic diseases. Different rules for the diagnosis of rheumatoid arthritis based upon classification criteria issued by the American Rheumatism Association were tested against each other. That diagnostic rule which had shown the best results was then further improved by a rheumatology expert, which finally yielded a sensitivity of 83.3% and a specificity of 95.3%. 相似文献
959.
A well-known problem in the domain of quantitative linguistics and stylistics concerns the evaluation of the lexical richness of texts. Since the most obvious measure of lexical richness, the vocabulary size (the number of different word types), depends heavily on the text length (measured in word tokens), a variety of alternative measures has been proposed which are claimed to be independent of the text length. This paper has a threefold aim. Firstly, we have investigated to what extent these alternative measures are truly textual constants. We have observed that in practice all measures vary substantially and systematically with the text length. We also show that in theory, only three of these measures are truly constant or nearly constant. Secondly, we have studied the extent to which these measures tap into different aspects of lexical structure. We have found that there are two main families of constants, one measuring lexical richness and one measuring lexical repetition. Thirdly, we have considered to what extent these measures can be used to investigate questions of textual similarity between and within authors. We propose to carry out such comparisons by means of the empirical trajectories of texts in the plane spanned by the dimensions of lexical richness and lexical repetition, and we provide a statistical technique for constructing confidence intervals around the empirical trajectories of texts. Our results suggest that the trajectories tap into a considerable amount of authorial structure without, however, guaranteeing that spatial separation implies a difference in authorship. 相似文献
960.
Based on a result on continuous dependence of solutions of an algebraic Riccati equation on the data matrices, we construct continuous curves of solutions of an algebraic Riccati inequality, and derive suboptimal Markovian estimates for the steady-state smoothing problem. 相似文献