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81.
Skill and risk taking are argued to be independent and to require different remedial programs. However, it is possible to contend that skill-based training could be associated with an increase, a decrease, or no change in risk-taking behavior. In 3 experiments, the authors examined the influence of a skill-based training program (hazard perception) on the risk-taking behavior of car drivers (using video-based driving simulations). Experiment 1 demonstrated a decrease in risk taking for novice drivers. In Experiment 2, the authors examined the possibilities that the skills training might operate through either a nonspecific reduction in risk taking or a specific improvement in hazard perception. Evidence supported the latter. These findings were replicated in a more ecological context in Experiment 3, which compared advanced and nonadvanced police drivers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
空心微珠改性硬质聚氯乙烯复合材料的应用研究   总被引:13,自引:1,他引:12  
经过改性的超细空心微珠可以作为填料加入到硬质聚氯乙烯(PVC-U)树脂中,同时改善PVC树脂的流变性、冲击性能和刚性等性能。研究结果表明,超细空心微珠加入到硬质PVC管材中,可以明显改善PVC硬管的加工流动性能,显著缩短塑化时间,降低最大扭矩。而超细空民微珠加入到硬质PVC板材时,可以提高PVC硬板的冲击性能,减小制品的收缩率,赋予PVC硬板优异的耐腐蚀性能,且产品的各项性能均符合PVC板材国家标准GB/T4454-96。  相似文献   
83.
The role of arginine vasopressin (AVP) in the nongenomic transfer of paternal behavior from fathers to offspring was examined in Peromyscus. Male California mice (P. californicus) exposed to fewer retrievals by white-footed mouse (P. leucopus) foster parents displayed fewer retrievals of biological offspring. In contrast, white-footed mice were retrieved equally rarely by California mouse foster parents and by biological parents and displayed no changes in pup retrieval behavior. AVP-immunoreactive staining in the bed nucleus of the stria terminalis may predict paternal behavior because it correlated positively with retrievals and with a score consisting of huddling, grooming, and time inside the nest. The authors discuss AVP as a possible mechanism by which early experience shapes adult paternal behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
This study examined the relationship between alliance and retention in family therapy. Alliance was examined at the individual (parent and adolescent) and family levels (within-family differences). Participants were 34 families who received functional family therapy for the treatment of adolescent (aged 12-18 years) behavior problems. Families were classified as treatment dropouts (n=14) or completers (n=20). Videotapes of the first sessions were rated to identify parent and adolescent alliances with the therapist. Results demonstrated that individual parent and adolescent alliances did not predict retention. However, as hypothesized, dropout cases had significantly higher unbalanced alliances (parent minus adolescent) than did completer cases. These findings highlight the importance of alliances in functional family therapy and suggest that how the alliance operates in conjoint family therapy may be a function of systemic rather than of individual processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
85.
We have evaluated the extent of public concerns about water management in the Palestinian Territory (PT) through a survey of the main Palestinian newspaper over the last thirteen years divided in three periods: pre (1984–1987), during (1988–1991), and post national uprising period (1992–1996). The public concern in the PT about various water management aspects was clear and influenced by the prevailing political conditions indicating (1) poor concerns in the first and second period where full Israeli military control of the PT and harsh practices prevailed with relatively more emphasis on regional water issues and (2) extensive-strong concerns in the third period when the peace process started and a partial lift of some of the Israeli water practices took place, along with an increased freedom in expressing public concerns which was granted with more emphasis on local issues and problems. Lack and limitation of water available to Palestinians, alternative solutions, and water quality and pollution control constituted the overwhelming majority of the topics of concern to the public for the three periods studied. Palestinian concerns were always greater than regional ones for the three periods and all of the topics considered. Public concern in the PT about all other water management aspects was poor and negligible especially in the first two periods. A massive increase in public concern has been observed in the third period in which the public expressed their concern over most water management aspects, indicating a possible change in public attitude toward water and water management and reflecting the change of the political status by the start of the peace process and the signing of the peace agreements.  相似文献   
86.
This paper deals with the application of continuous thermodynamics to light and heavy oil systems using the Peng- Robinson equation of state. The composition of the high molar mass components in a reservoir oil is described by a continuous distribution function of some characterizing quantity, e.g. molar mass or boiling temperature. Numerical Gaussian quadrature methods are used to generate pseudo-components and their mole fractions from distribution data. Several examples are presented for phase equilibria of solvent/crude oil systems. The results showed that semi-infinite distribution functions, such as the Γ function, cannot be applied to all cases, e.g. dew point calculations. The Gauss- Legendre quadrature method coupled with spline fitting worked best for heavy oil systems.  相似文献   
87.
本文通过钢筋混凝土梁以及在受拉区部分地加入钢纤维的钢筋混凝土梁的试验及理论分析,研究了钢纤维混凝土层厚、钢纤维体积率和剪跨比对钢筋钢纤维增强部分混凝土梁受剪性能的影响,建立了与普遍钢筋混凝土梁受剪承载力计算公式相衔接的钢筋钢纤维增强部分混凝土梁受剪承载力的计算模型和计算公式.  相似文献   
88.
凝析气井井筒动态预测方法   总被引:2,自引:0,他引:2  
利用垂直管流公式,结合流体相平衡热力学闪蒸计算,运用状态方程模拟,给出凝析气井井筒动态预测新方法.根据该方法.结合油藏数值模拟计算的结果,可准确地预测不同生产时期凝析气井的井筒动态.  相似文献   
89.
用毛细管流变仪研究了乙基纤维素(EC)及其高密度聚乙烯(HDPE)复合物,纤维素芳族酯(CAE)及其聚碳酸酯(PC)复合物的剪切流变特性和机理。结果表明,EC对HDPE/EC复合物的粘度影响不大,而少量(5%)CAE的加入使PC/CAE复合物粘度大大下降,且复合物流变曲线呈现新的特征。  相似文献   
90.
The Early Career Awards recognize the large number of excellent young psychologists. Recipients of this award may not have held a PhD for more than nine years. The areas considered in 1991 were animal learning and behavior, developmental, and personality. The winners for 1991 were Kent C. Berridge, Susan A. Gelman, and Randy J. Larsen. For each winner a citation, biography, and selected bibliography of their works are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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