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71.
Using self-determination theory, the authors tested a motivational model to explain the conditions under which rural students formulate their intentions to persist in, versus drop out of, high school. The model argues that motivational variables underlie students' intentions to drop out and that students' motivation can be either supported in the classroom by autonomy-supportive teachers or frustrated by controlling teachers. LISREL analyses of questionnaire data from 483 rural high school students showed that the provision of autonomy support within classrooms predicted students' self-determined motivation and perceived competence. These motivational resources, in turn, predicted students' intentions to persist, versus drop out, and they did so even after controlling for the effect of achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
Fodor and Pylyshyn (1988) have argued that the cognitive architecture is not Connectionist. Their argument takes the following form: (1) the cognitive architecture is Classical; (2) Classicalism and Connectionism are incompatible; (3) therefore the cognitive architecture is not Connectionist. In this essay I argue that Fodor and Pylyshyn's defenses of (1) and (2) are inadequate. Their argument for (1), based on their claim that Classicalism best explains the systematicity of cognitive capacities, is an invalid instance of inference to the best explanation. And their argument for (2) turns out to be question-begging. The upshot is that, while Fodor and Pylyshyn have presented Connectionists with the important empirical challenge of explaining systematicity, they have failed to provide sufficient reason for inferring that the cognitive architecture is Classical and not Connectionist.  相似文献   
73.
根据一大块式曲柄连杆机构的机器钢筋混凝土基础的振动测试与振动分析 ,诊断了基础发生工程事故的原因 ,并结合工程特点 ,在不改变基础设计的动力参数的情况下 ,确定了灌浆加固处理方法 ,并介绍了灌浆加固处理的效果。  相似文献   
74.
网络财务是网络时代和电子商务发展的必然趋势 ,本文介绍了网络财务的特征及其会计理论 ,并就其在实施过程中可能出现的风险提出了相应对策  相似文献   
75.
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   
76.
Presents the citation, biography, and selected bibliography for Robert B. McCall, one of the 1994 recipients of the American Psychological Association's Award for Distinguished Professional Contributions--Distinguished Professional Contributions to Public Service. From McCall's citation: "Building on a prolific research career in child development, Robert B. McCall communicated the scientific findings of his colleagues to the public through the mass media, winning four national awards and demonstrating to a sometimes skeptical profession that such articles and TV programs could be both accurate and interesting. Subsequently, he became the inaugural director for the University of Pittsburgh Office of Child Development, a unique interdisciplinary, university-community facilitative unit that has broadened the definition of university public service to embrace partnerships among faculty and community service professionals, funders, and policymakers that have created innovative interdisciplinary training and research programs, human service demonstration and evaluation projects, and policy studies." (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
The engineering and management of human safety is an important societal objective that includes extensive efforts by governments, both legislative and administrative, to enhance the health and safety of the public. Although the achievement of safety goals depend primarily on individuals and organizations responsible for safety, much support is drawn from expertise in diverse scientific and engineering disciplines. The activities range from structural safety (dams, tunnels, bridges to tall buildings) to safe operation of hazardous industrial installations (energy generation facilities, LNG terminals, petrochemical plants) to transportation systems (airline, rail, car safety) to technologies designed to minimize adverse impacts on the environment. All these activities are crucially concerned with risk: with the likelihood and the probable effects of various measures on life and health. We have developed a unified rationale and a clear basis for effective strategic management of risk across diverse sectors. Safety is an important objective in society but it is not the only one. The allocation of society's resources devoted to safety must be continually appraised in light of competing needs, because there is a limit on the resources that can be expended to extend life. The paper presents the Life Quality Index (LQI) as a tool for the assessment of risk reduction initiatives that would support the public interest and enhance safety and quality of life. The paper provides an intuitive reformulation of the LQI as equivalent to a valid utility function that is consistent with the principles of rational decision analysis. The LQI is further refined to consider the issues of discounting of life years, competing background risks, and population age and mortality distribution. The LQI is applied to quantify the societal willingness-to-pay, which is an acceptable level of public expenditure in exchange for a reduction in the risk of death that results in improved life-quality.  相似文献   
78.
阐述了甲醇制低碳烯烃各个工艺的研究进展,从甲醇制乙烯、甲醇制丙烯和甲醇制丁烯三个方面对比了各自技术特点,指出未来需开发出以丙烯、 C4烯烃为主产品的新技术。  相似文献   
79.
赵国庆 《包钢科技》2002,28(6):78-80,85
本文介绍了包钢历年来氟污染治理成效以及控制外排氟总量达标的具体措施.  相似文献   
80.
化学结构式的拓扑描述   总被引:1,自引:0,他引:1  
化学结构式的拓扑描述,是化学信息计算机化的手段之一。这里系统地建立了一整套的连接表(三类:紧缩连接表、冗余连接表、和连接方阵),用来进行结构式中原子之间连接关系的拓扑描述,对分子结构进行数值化。同时,阐述了连接表唯一化的方法,并介绍了不同类型连接表之间的转换关系和还原为平面结构式图形的绘图程序。  相似文献   
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