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971.
Twenty domestic Muscovy ducks were trained to traverse a runway for food reward. Subjects were then randomly assigned to treatments. In one treatment, subjects received six nonrewarded trials followed by six rewarded trials every day for 12 days; and, in the other treatment, subjects received six rewarded trials followed by six nonrewarded trials every day for 12 days. These successive acquisition and extinction (SAE) treatments were selected because different extinction rates on the nonrewarded trials are expected on the bases of previous research performed with rats. Analyses of variance revealed the former treatment yielded significantly greater resistance to extinction than did the latter treatment. It was concluded that ducklings performed similarly to rats in the above SAE situation. 相似文献
972.
Requests for monographs generated within an interlibrary loan network are analyzed for half-life statistics. It is suggested that demand represents use of the literature more completely than satisfied requests or circulation statistics. Demand in this study is characterized as either regional demand or statewide demand and is related to the level of the network where final processing of the request occurs. A negative exponential distribution is found to adequately characterize both levels of demand as a function of publication date for four subject categories. Corrected demand data is obtained by removing the growth rate of most of the available literature represented by American book publisher output. Based on over 10,000 interlibrary loan requests, negative exponential distributions describe the raw data as well as the corrected data. A shorter half-life was found for regional library demand (10.47 yr) than that found for statewide library demand (15.75 yr). Applying the correction factor to reflect the growth rate of the available literature tends to increase the half-life when compared to the raw data, and changes the ordering of subject classes with respect to ascending half-lives. 相似文献
973.
974.
975.
To facilitate the adoption of a common core curriculum in the Schools of Engineering and of Mining at the University of Arizona, the general physics course for engineers has been dropped. The physical foundation for engineering is taught in a new series of courses in the Civil, Mechanical, Electrical Engineering, and Physics Departments as part of the common core. The Physics Department teaches atomic, molecular, nuclear, and solid-state physics in a seven-unit junior-level course. There are grounds for a re-examination of the role of physics in engineering education and perhaps for extensive changes. It is suggested, however, that the role is, and should remain, vital, in the interests of science, of engineering, and of education. 相似文献
976.
977.
978.
Various approaches have been used in training people to effectively function in a foreign culture. This paper reviews six approaches that are currently being used in cross-cultural training. The approaches reviewed are: (1) the intellectual approach, (2) the area simulation approach, (3) the self-awareness approach, (4) the culture awareness approach, (5) the behavioral approach, and (6) the interaction approach. The advantages of using an “integrated” approach to cross-cultural training is discussed and research is presented which supports the effectiveness of this approach. The results offer preliminary evidence that an integrated approach to training can improve participants' attitudinal satisfaction with their stay in another culture. Finally, the paper offers suggestions for the future direction of cross-cultural training. 相似文献
979.
980.
The evolution of graduate education in electrical engineering began in the early 1890' s and progressed at a rapid pace in the 1920' s, particularly in metropolitan areas conscious of community needs. In these areas, evening programs held the spotlight because of the ever-demanding need to provide graduate engineers with advanced knowledge. Such cooperation between community interests and colleges has resulted in a wide variety of patterns of part-time study on campus and, more recently, off campus. The later development is viewed with criticism in several educational circles although off-campus programs are filling tremendous requirements arising from industrial concentrations not within easy reach of a university or college. The evolution seems to indicate that off campus programs are not a passing fancy and that such requirements are very likely to be best satisfied in the long run by the establishment of graduate centers with a faculty in residence. As an example, the Polytechnic Graduate Center on Long Island is described. (The Center, actually located in Farmingdale, N. Y., began its operation on September 25, 1961, with a graduate student body of nearly 700 in day and evening programs involving advanced courses in Aerospace Engineering, Electrical Engineering, Electrophysics, Mathematics, Mechanical Engineering, Physics, and Industrial Management. Close to 150 part-time day students are attending on a released-time basis, in addition to 45 full-time students in residence.) 相似文献