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41.
42.
C. N. Cacaval E. C. BuruianÎ D. Rou E. Rusu G. E. Grigoriu V. Brboiu 《Polymer International》1985,17(4):343-346
Thermogravimetry and pyrolysis in combination with gas chromatography and infrared spectroscopy were the experimental techniques applied to the thermal degradation of cinnamoylated poly(vinyl alcohol) samples, constituted from vinyl alcohol-vinyl cinnamate photocrosslinkable copolymers. The thermal decomposition products include gases, liquids and solids. The gases are formed from saturated and unsaturated volatile hydrocarbons C1? C4, carbon monoxide and carbon dioxide. The liquid fraction includes aromatic hydrocarbons and some oxygenated organic compounds. The solid product identified in the greatest amount was cinnamic acid. The content in the thermal decomposition products varies considerably both with copolymer composition and temperature. 相似文献
43.
44.
何明一 《电子科学学刊(英文版)》1994,11(1):1-10
A new concept, the generalized inverse group (GIG) of signal, is firstly proposed and its properties, leaking coefficients and implementation with neural networks are presented. Theoretical analysis and computational simulation have shown that (1) there is a group of finite length of generalized inverse signals for any given finite signal, which forms the GIG; (2) each inverse group has different leaking coefficients, thus different abnormal states; (3) each GIG can be implemented by a grouped and improved single-layer perceptron which appears with fast convergence. When used in deconvolution, the proposed GIG can form a new parallel finite length of filtering deconvolution method. On off-line processing, the computational time is reduced to O(N) from O(N2). And the less the leaking coefficient is, the more reliable the deconvolution will be. 相似文献
45.
群时延精确设计的全差分四阶Bessel滤波器 总被引:1,自引:0,他引:1
采用MOS管有源电阻,提出了一种全差分R-MOSFET-C四阶Bessel有源低通滤波器,.通过调节工作于亚阈值区的CMOS管的沟道导纳补偿电阻值的大小,能抵消集成电路制造工艺中电阻值的一致偏差,实现Bessel有源滤波器群时延的精确设计.根据无源滤波器的状态方程完成有源滤波器的综合,应用3.3V,0.5μm CMOS工艺完成了群时延大小为0.75μs的四阶Bessel低通滤波器的管极计算机仿真,仿真结果表明所提电路正确有效,适于全集成. 相似文献
46.
通过对枣庄矿区污染防治工作的调查研究,分析了煤矿开采对环境的影响,总结出当前煤矿污染防治的适用技术群,井对其相关问题进行评价。 相似文献
47.
The authors propose a behavioral decision theory relevant to the maintenance of desirable identities. The theory, termed deviance regulation theory (DRT), predicts that actions translate into meaningful identities to the extent that they cause the individual to deviate from reference group norms. This straightforward proposition is used to predict the patterning of behavior across a wide array of social contexts. The authors present evidence that predictions generalize across Eastern and Western cultures and to both personal and collective identities. Finally, they show how DRT alters current theoretical assumptions about social motives and social and cultural influence, and they illustrate how it can help explain the structure of both informal and formal social forces. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Solubility of dimethyl-2,6-naphthalene dicarboxylate in acetic acid, N,N-dimethylfonnamide, N,N-dimethyl acetamide, dimethyl sulphoxide, and N-methyl-2-ketopyrrolidine were determined using a dynamic method. The measured systems were correlated by UNIFAC group contribution method. A new main group (aromatic ester, ACCOO) was defined to express the activity coefficients of the aromatic ester. New interaction parameters of the ACCOO group were expressed as the first-order function of temperature and were determined from the experimental data. The calculated results for the new interaction parameters were satisfactory. The measured systems were also correlated with the Wilson and 2-h models, and the results were compared with those of the UNIFAC model. 相似文献
49.
Guimond Serge; Dambrun Micha?l; Michinov Nicolas; Duarte Sandra 《Canadian Metallurgical Quarterly》2003,84(4):697
Social dominance orientation (SDO) has been proposed as an important variable in the explanation of prejudice. We distinguish between three conceptualizations of SDO: SDO as a personality trait (personality model), SDO as a moderator of the effects of situational variables (Person X Situation model), and SDO as a mediator of the effect of social position on prejudice (group socialization model [GSM]). Four studies (N = 1,657) looking at the relations between social positions, SDO, and prejudice in a natural setting and in a laboratory setting provide strong support for the GSM. In contrast to previous correlational findings, there is evidence of a cause (dominant social position), an effect (prejudice increases), and a mediator (SDO). These results suggest new perspectives on the integration of individual and contextual determinants of prejudice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
WANG Ju-hui 《通讯和计算机》2008,5(11):48-52
This paper comes true a system of facial detection and location. Firstly, it realizes the facial detection of candidate region used skin color for the given image, and considers the influence of similar skin. Secondly, it realizes the location for eye region used the gray characteristic of eye and correction of central measurement, and makes further selection for facial candidate region. The end, it normalizes the facial image and makes it as front standard image, so realizes the facial characteristic location. 相似文献