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41.
有可能用于鱼雷尾流自导的某些光学特征 总被引:2,自引:0,他引:2
介绍了尾流自导鱼雷特点,研究了真实尾流的光学特性,提出了用于鱼雷尾流自导可能的光学特征。 相似文献
42.
结合新版建筑工程施工质量验收规范的学习和施工实践 ,介绍了新版标准与旧标准的差异和特点 ,并就如何贯彻实施新标准、准确掌握检验批等问题作了分析 ,提出了执行中的相关注意事项。 相似文献
43.
Wide variability exists with respect to how breast cancer survivors respond to common psychological and psychosocial challenges of their disease, ranging from posttraumatic stress disorder to posttraumatic growth. This cross-sectional study examined contextual, disease-related, and intraindividual predictors of posttraumatic growth in 224 randomly selected breast cancer survivors. A series of hierarchical regression analyses found that age at diagnosis, marital status, employment, education, perceived intensity of disease, and active coping accounted for 34%, 35%, and 28% of the variance in growth in relationships with others, new possibilities, and appreciation for life. These findings suggest that a more comprehensive model of growth will be helpful in understanding the various factors that play a role in breast cancer survivors' perception of psychological and psychosocial growth. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
Hishinuma Earl S.; Else 'Iwalani R. N.; Chang Janice Y.; Goebert Deborah A.; Nishimura Stephanie T.; Choi-Misailidis Soojean; Andrade Naleen N. 《Canadian Metallurgical Quarterly》2006,21(3):286
School psychologists are generally not provided with the knowledge and skills to address both educational and psychosocial issues of Asian American and Pacific Islander students. The present study is the first of its kind in examining 36 independent (i.e., demographic, social, cultural, psychological) variables in association with four school outcomes (i.e., grade point average, absences, suspensions, and school infractions) with a large sample of Caucasian, Filipino, Native Hawaiian, Japanese, mixed/non-Hawaiian, and "other" Hawai'i high school students (N = 2,833). Given the relatively unique sample in question and the sheer number of variables, an exploratory approach was utilized with the goal of determining the most robust independent variables, with the unique inclusion of Hawaiian cultural identification. A cross-validation technique was used, whereby stepwise regressions were performed for each of two cross-validation samples; only common variables were retained in a final stepwise model for each of the four school outcomes. The results indicated that, remarkably, substance use accounted for the most variance (i.e., 8.4% -16.1 %) in the four school measures. Further analyses detailed the relationship, including the finding that smoking cigarettes regularly, accounted for the most variance compared to the other five substance use items. Further research and implications of the findings are discussed, including the need for prevention and intervention programs that incorporate substance use as a component, both within and outside of school environments. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
45.
Lopez Frederick G.; Fons-Scheyd Alia; Morúa Wendy; Chaliman Rebecca 《Canadian Metallurgical Quarterly》2006,53(4):543
This study examined the nature and impact of dyadic perfectionism over a 3-month interval within a sample of 116 college students who were currently involved in an intimate heterosexual relationship. Dyadic perfectionism scores were stable and correlated as expected with scores on concurrent measures of adult attachment orientations and relationship satisfaction. Logistic regression analyses revealed that, controlling for initial commitment status and adult attachment orientations, Time 1 dyadic perfectionism scores significantly and uniquely predicted relationship continuity 3 months later. Lastly, controlling for social desirability, relationship commitment status, and Time 1 adult attachment orientation scores, Time 1 dyadic perfectionism scores also uniquely predicted Time 2 relationship distress. Findings provide additional evidence that dyadic perfectionism is a risk factor for relationship dysfunction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
《Materials and Manufacturing Processes》2006,21(8):819-823
Linear elastic fracture mechanics was used to optimize the vacuum heat-treatment procedures for conventional hot-work AISI H11 tool steel. The fracture toughness was determined with non-standard, circumferentially notched and fatigue-precracked tensile-test specimens. The fracture-testing method is sensitive to changes caused by variations in the microstructure resulting from the austenitizing and tempering temperatures as well as the homogeneity of the material itself. The combined tempering diagram- Rockwell-C hardness, Fracture toughness KIc, Tempering temperature was used for the choice of the vacuum heat-treatment parameters necessary to obtain the best properties for a given application with respect to the investigated steel. 相似文献
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49.
长江口北支水道水沙特性分析 总被引:10,自引:1,他引:9
从实测资料出发,结合水流数值计算成果,对长江口北支水道的水流、泥沙和含盐度等资料进行分析,得出了北支水道的水沙特性,并分析了水沙变化与河床变化的相互关系.北支水道在1958年南通河段河势控制后,径流分流比逐年下降,并渐趋稳定于3%左右.北支水道受径流影响越来越小,主要受潮流作用.随着水沙特性的逐年变化,北支水道0 m以下槽蓄容量逐年减小,并渐趋稳定,北支上段为逐年淤积最快的区域.由此反过来影响了水沙条件的进一步变化,使北支上段平均潮差增加,北支的会潮点由崇头附近下移至青龙港附近. 相似文献
50.
本文研究了加法复合布尔函数和乘法复合布尔函数,在平衡性、k次项系数、K次扩散准则(PC)、相关免疫 性(CI)、Walsh谱、代数次数、小项分布等方面得到了一批新结果。 相似文献