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141.
We document some basic facts about how liquids behave in the low gravity of outer space and how this poses challenges to space
scientists and engineers who need to design and test systems that handle fluids in outer space while working in the 1-g environment
on Earth.
N Ananthkrishnan is Director, Coral Digital Technologies (P) Ltd, a Bangalore-based company working in the area of multidisciplinary
simulation and system integration of aerospace, naval and surface vehicles, and in the design and development of autonomous
unmanned/micro air vehicles. 相似文献
142.
Sex differences in the etiology of aggressive and nonaggressive antisocial behavior: results from two twin studies 总被引:6,自引:0,他引:6
Recent theory and results from twin and adoption studies of children and adolescents suggest greater genetic influence on aggressive as compared to nonaggressive antisocial behavior. In addition, quantitative or qualitative differences in the etiology of these behaviors in males and females have been indicated in the literature. The Child Behavior Checklist was completed by the parents of 1022 Swedish twin pairs aged 7-9 years and of 501 British twin pairs aged 8-16 years. Genetic factors influenced aggressive antisocial behavior to a far greater extent than nonaggressive antisocial behavior, which was also significantly influenced by the shared environment. There was a significant sex difference in the etiology of nonaggressive antisocial behavior. Bivariate analyses supported the conclusion that the etiologies of aggressive and nonaggressive antisocial behavior differ for males and females. 相似文献
143.
时代呼唤我国设置科学教育本科专业 总被引:12,自引:0,他引:12
本文针对经济全球化、教育国际化的时代背景,从我国当前基础教育课程改革、教师专业化发展趋势、科学教育学科建设以及科学普及事业的发展四方面论述了我国新一轮普通高等学校学科专业结构调整中设置科学教育本科专业的必要性。 相似文献
144.
Wouter P.C. BoonAuthor Vitae Ellen H.M. Moors Author VitaeStefan Kuhlmann Author Vitae Ruud E.H.M. Smits Author Vitae 《Research Policy》2011,40(2):242-252
User involvement is assumed to be beneficial to innovation processes. Intermediary user organisations contribute to articulating societal demands for innovations. However, the learning processes inside these organisations are still not understood well. Therefore, this paper empirically investigates intermediaries using an event history approach. It yields characteristic learning mechanisms, e.g. concerning the management of expectations or actively building a case. If intermediaries overcome challenges regarding positioning, representation and the level of proactivity, they can play a precarious role in demand articulation in the context of new technologies. 相似文献
145.
中学课外体育活动现状调查与对策 总被引:1,自引:0,他引:1
就东营市、滨州市中学课外体育活动的现状作了调查 ,发现如下问题 :初中有 67 80 %学校不开展早操 ;课外活动开展率为 65 % ,远低于全国学生的 86% ;课程负担重是导致学生不参加课外体育活动的主要原因 ;运动队学生文化课成绩与其他学生文化课相比较差 ,有随年级增高逐渐下降的趋势 .针对调查中发现的问题 ,结合东营市、滨州市的实际 ,提出了加强中学课外体育活动的对策 相似文献
146.
Erkko Tapio Sointu Hannu Savolainen Matthew C. Lambert Kristiina Lappalainen Michael H. Epstein 《European Journal of Psychology of Education - EJPE》2014,29(1):1-19
When rating scales are used in different countries, thorough investigation of the psychometric properties is needed. We examined the internal structure of the Finnish translated Behavioral and Emotional Rating Scale-2 (BERS-2) using Rasch and confirmatory factor analysis approaches with a sample of youth, parents, and teachers. The results suggested that the Finnish translated BERS-2 has acceptable measurement properties and is suitable for use in Finnish schools. Results highlighted the issue that there is a need to consider cross-cultural aspects when introducing new measures in another culture. Directions for future research are also discussed in light of present findings. 相似文献
147.
Betty E. Kunkel L.M.F.C. 《Child abuse & neglect》1983,7(4):479-484
THIS BRIEF COMMUNICATION addresses program abuse in out-of-home placement which deepens what we identify as the alienation response in the already alienated child. Alienation is defined as a state of feeling separate, apart, not being able to relate effectively with another, not belonging, and with impaired ability to connect the inside world of feelings with the outside environment. Program abuse is seen as any act or condition permitted in a program that further alienates a child. In evaluating a child's degree of alienation and developing creative methods to reach the most severely “child alone,” the use of the Alienation Chart in Figure 1, has been helpful to our staff. 相似文献
148.
G. M. Sankolli M. I. Khatkhatay M. P. Desai D. K. Pardhe P. C. Ishrad U. M. Joshi 《Indian journal of clinical biochemistry : IJCB》1992,7(1):71-74
Aprototype kit for the detection of occurrence of ovulation based on urinary pregnanediol glucuronide estimations by ELISA
was developed in our laboratory. This kit was sent for evaluation at 4 centres in Bombay and Pune, India. The diagnosis of
ovulation/anovulation based on the results of the kit is comparable with that based on reference parameters commonly used
(ultrasonography of ovarian follicles and serum progesterone estimations). The accuracy of the test was 93.5%, specificity
was 87.5% and sensitivity was 95.7%. This rapid indigenous test can be very useful in assessing ovulatory status of the woman
by the clinicians in their offices. 相似文献
149.
150.
Stress analysis of anisotropic thick laminates in cylindrical bending using a semi-analytical approach 总被引:1,自引:0,他引:1
LU Chao-feng LIM C.W. XU Feng 《浙江大学学报(A卷英文版)》2007,8(11):1740-1745
Semi-analytical elasticity solutions for bending of angle-ply laminates in cylindrical bending are presented using the state-space-based differential quadrature method (SSDQM). Partial differential state equation is derived from the basic equations of elasticity based on the state space concept. Then, the differential quadrature (DQ) technique is introduced to discretize the longitu- dinal domain of the plate so that a series of ordinary differential state equations are obtained at the discrete points. Meanwhile, the edge constrained conditions are handled directly using the stress and displacement components without the Saint-Venant principle. The thickness domain is solved analytically based on the state space formalism along with the continuity conditions at interfaces. The present method is validated by comparing the results to the exact solutions of Pagano’s problem. Numerical results for fully clamped thick laminates are presented, and the influences of ply angle on stress distributions are discussed. 相似文献