On computing a buy/copy policy using the Pitt-Kraft model     

Harvey J. Greenberg  Donald H. Kraft 《Information processing & management》1977,13(2):125-134

The Pitt-Kraft model of buying versus photocopying results in a small, but complex, nonlinear program. This paper identifies a Kuhn-Tucker point and demonstrates that for certain parameter values it is not optimal. A policy generation procedure is presented; the purpose is to prevent convergence of a primal algorithm to this inferior policy, which satisfies the Kuhn-Tucker optimality conditions.  相似文献   

Book reviews     

Robert Heinich  Vincent Lanier  John A. Carpenter  Herbert I. Schiller  Donald D. Jensen  Carl E. Helm  James Russell  A. Thiagarajan  Arthur Babick 《Educational technology research and development : ETR & D》1969,17(3):327-342

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Academic stress of international students attending U.S. universities   总被引：1，自引：0，他引：1  

Teh-yuan Wan  David W. Chapman  Donald A. Biggs 《Research in higher education》1992,33(5):607-623

This study investigated factors associated with the academic stress experienced by international students (N=412) attending graduate school in the United States. The study was grounded in a cognitive framework in which academic stress is understood as the consequence of students' appraisal of the stressfulness of role demands and their perception of their ability to cope with those demands. These two appraisals, in turn, were posited to be a function of cultural distance, students' social support network, and their role competencies. Results indicated that the primary determinants of the two types of appraisals differed. While self-perceived English-language skills and, to a lesser degree, cultural distance were the predictors of primary appraisal, self-perceived English-language, academic, and problem-solving skills and social support network were the main determinants of secondary appraisal. Implications for how universities might work more effectively with international students are discussed.  相似文献   

Warning: Assessment may be hazardous to your curriculum     

Michael Knight  Donald Lumsden 《Assessment Update》1992,4(3):6-8

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Comments on “The importance of terminology in teaching K– 12 science”     

Donald R. Daugs  Robert E. Yager 《科学教学研究杂志》1984,21(9):957-959

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Research abstracts     

Editor Donald P. Ely 《Educational technology research and development : ETR & D》1993,41(2):125-128

Abstracts are compiled by Nancy R. Preston, ERIC Clearinghouse on Information Resources, Syracuse University, Syracuse, NY 13244-2340. Telephone: 315-443-3640. Internet: ERIC@SUVM.SYR.EDU.  相似文献   

Using the Q-sort as a predictor of academic success in self-paced,individualized science classes     

Larry Melton  Donald Humphreys 《科学教学研究杂志》1980,17(3):243-249

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Diurnal patterning of eight activities in 14 species of muroid rodents     

Denis J. Baumgardner  Susan E. Ward  Donald A. Dewsbury 《Learning & behavior》1980,8(2):322-330

The diurnal patterning of locomotion, stereotypy, grooming, eating, drinking, sleeping, postural readjustment, and inactivity was studied in 14 species of muroid rodents in the laboratory using a visual observation technique.Microtus canicaudus, M. montanus, M. ochrogaster, andM. pennsylvanicus exhibited acyclic activity patterns, whilePeromyscus eremicus,P. gossypinus, P. leucopus, P. maniculatus bairdi, P. polionotus, Calomys callosus, Mus musculus, andOnychomys leucogaster displayed nocturnality in their behavioral patterning.Rhabdomys pumilio exhibited crepuscular activities andNeofiber alleni displayed a complex pattern of nocturnality. Species differed in total amount of time spent per day for all activities but eating. The acyclicity ofMicrotus species appears to be related to high metabolic rates and a semifossorial life-style.  相似文献   

Proactive effects in pigeons’ timing behavior: Implications for an internal-clock model     

Donald M. Wilkie 《Learning & behavior》1988,16(2):132-136

We have found proactive effects in pigeons’ timing behavior, a finding inconsistent with internal-clock models of timing that assume a resetable working-memory component. Six pigeons were trained to discriminate between 2- and 10-sec illuminations of a white light; choice of a red pecking key was correct and rewarded after presentation of the short stimulus whereas choice of a green key was correct and rewarded after presentation of the long stimulus. During training sessions, there were 60 trials separated by a 20-sec intertriai interval; short and long light occurred in a randomized order and correct choices were reinforced with 5-sec access to grain on a partial (75%) schedule. During test sessions, there were 120 trials separated by a 2-sec intertrial inter val. Light presentations occurred in a fixed order throughout these sessions: 2, 6, 10, 10, 6, 2 2, 6, 10 sec, and so forth. Choice of either red or green after 6 sec was not reinforced. However, red continued to be correct after 2 sec and green continued to be correct after 10 sec. Of central interest was how the subjects classified 6 sec of light in ascending (2, 6, 10) and descending (10. 6, 2) sequences of durations: Subjects chose the short alternative on 42% of the 6-sec trials in ascending series but only 29% in descending series, a result most plausibly interpreted as show ing that duration information from a preceding trial affects duration classifications on the cur rent trial. Such proactive effects should not occur according to working-memory models that as sume that stored information is cleared at the end of a trial.  相似文献   

Achieving the educational standards we need     

Donald M. Stewart 《Assessment Update》1992,4(1):1-7

This article is based on remarks presented by Donald M. Stewart at the Open Forum on National Standards held at the Second National Conference on School/College Collaboration, cosponsored by the American Association for Higher Education and the College Board in Atlanta, Georgia, on July 26, 1991.  相似文献