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991.
Human subjects were exposed to a concurrent-chains schedule in which reinforcer amounts, delays, or both were varied in the terminal links, and consummatory responses were required to receive points that were later exchangeable for money. Two independent variable-interval 30-s schedules were in effect during the initial links, and delay periods were defined by fixed-time schedules. In Experiment 1, subjects were exposed to three different pairs of reinforcer amounts and delays, and sensitivity to reinforcer amount and delay was determined based on the generalized matching law. The relative responding (choice) of most subjects was more sensitive to reinforcer amount than to reinforcer delay. In Experiment 2, subjects chose between immediate smaller reinforcers and delayed larger reinforcers in five conditions with and without timeout periods that followed a shorter delay, in which reinforcer amounts and delays were combined to make different predictions based on local reinforcement density (i.e., points per delay) or overall reinforcement density (i.e., points per total time). In most conditions, subjects' choices were qualitatively in accord with the predictions from the overall reinforcement density calculated by the ratio of reinforcer amount and total time. Therefore, the overall reinforcement density appears to influence the preference of humans in the present self-control choice situation.  相似文献   
992.
Reviews     
《Zygon》1998,33(1):155-164
Thomas Ryba, The Essence of Phenomenology and Its Meaning for the Scientific Study of Religion
Daniel C. Dennett, Darwin's Dangerous Idea: Evolution and the Meaning of Life
Edited by Clifford N. Matthews and Roy A. Varghese, Cosmic Beginnings and Human Ends: Where Science and Religion Meet  相似文献   
993.
“以毒攻毒”与中西医结合研究   总被引:8,自引:2,他引:6  
“以毒攻毒”是中医药学一个重要医理和治则。本文介绍了国内外有关“以毒攻毒”的研究进展,以及具有“以毒攻毒”特点的医药研究状况。特别是德国细菌学家贝林等,研制成功破伤风和白喉抗毒素。我国学者张亭栋教授与陈竺教授,继承发掘中药砒霜治疗世界性难治病—急性早幼粒细胞白血病,取得国际领先水平的科研成果等等,表明中西医结合研究是继承发展中医药学的有效方法和途径。  相似文献   
994.
管理者影响策略的结构   总被引:2,自引:0,他引:2  
本研究根据中国企事业组织内管理者对他人发挥影响力的特点 ,选取反映中国文化的影响计策编成题目 ,并与西方背景下构建的组织影响策略量表汇编成问卷。 2 1 8位中国管理者用汇编的问卷评定他们与直接上司和直接下属在工作中相处时使用这些计策的频率。结果发现 ,在因素水平有“应变控制”和“温情说服”两个正交因素。这两个因素跨影响方向一致。对各因素内的题目做聚类分析 ,发现大多数聚类的内容跨影响方向的一致性不高。与西方的组织策略量表对照 ,因新题目的加入 ,汇编的影响计策量表内的聚类更好地反映了中国管理者使用影响计策的特点。  相似文献   
995.
Nelson  George C. 《Studia Logica》1998,60(3):343-355
Many results concerning the equivalence between a syntactic form of formulas and a model theoretic conditions are proven directly without using any form of a continuum hypothesis. In particular, it is demonstrated that any reduced product sentence is equivalent to a Horn sentence. Moreover, in any first order language without equality one now has that a reduced product sentence is equivalent to a Horn sentence and any sentence is equivalent to a Boolean combination of Horn sentences.  相似文献   
996.
We examined enrichment and stress in 214 families who had children with severe emotional disorders. Caregivers' ratings of enrichment and stress were obtained through a newly developed instrument, the Effects of the Situation Questionnaire, which used parallel items covering 17 life areas. While ratings of stress were generally higher than enrichment, caregivers reported some enrichment in areas encompassing self concept and family relationships, Bivariate and multivariate analyses using various child, family, and service-system variables revealed that stress was notably associated with severity of the child's disorder, low empowerment, and a lack of coordination among service providers. Enrichment was unrelated to severity but associated with high empowerment and spiritual support. Our findings suggest that families' experiences of caregiving can have both positive and negative aspects and that a comprehensive approach to serving and studying families should take both into account.  相似文献   
997.
The basic (negative and positive) methodological maxims of three currents of philosophy of science (logical empiricism, falsificationism, and postpositivism) are formulated. Many of these maxims (stratagems) are controversial, e.g., the stance about the nonsense of metaphysics, and that of its indispensability. The restricted validity of these maxims allows for their unification. Within the framework of most of them there may be a relationship of (synchronic, or diachronic) subordination of the contradicting desiderata. In this vein ten stratagems are formulated. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
998.
本研究以现代教育心理学体系为框架,采用资料整理法,对梁启超的学习心理学思想进行了分析归纳。从中可以看出,梁启超重视学习兴趣,并把无所为、不息、深入研究、找朋友作为保持兴趣的方法;认为做学问的人应具备明敏、密察、别裁、通方等能力和忠实、深切、敬慎、不倦的习惯;并总结出了立志、善观、持敬、明义理、养成读书兴趣等学习方法。  相似文献   
999.
Significant relationships between the Holland Vocational Preference Inventory (VPI) and the Strong Vocational Interest Blank (SVIB) were again empirically demonstrated in this study, and conversion equations were developed to use standard scores of SVIB scales, rather than items, to produce estimates of VPI scores. Cross validation on a limited population yielded supportive evidence that these conversion equations can provide meaningful VPI estimates from SVIB scale scores. The need for validation across a variety of populations was underscored in order to assess further generalizability of these findings.  相似文献   
1000.
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