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41.
Close relationships between and among supply chain members are becoming more prevalent. However, there is lack of agreement in the literature and in practice concerning the characteristics of different interorganizational relationships. The resultant confusion is an obstacle to the progression of research and could cause problems among firms in a supply chain. Based on previous research and an exploratory study conducted with company executives responsible for supply chain management activities, this article seeks to introduce the concept of relationship magnitude (i.e., the extent or degree of closeness or strength of the relationship) and differentiate it from relationship type (i.e., classes of relationships that share common traits). Implications for managers and opportunities for future research are provided.  相似文献   
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This analysis investigates the assertion that the baby-boom cohorts, by virtue of their large size and new lifecourse redistribution tendencies, are likely to initiate significant shifts in the distribution of the elderly population as these cohorts enter into the 65-and-older age categories. The author contends that cohorts' pre-elderly lifecourse migration patterns should be incorporated into studies of elderly population distribution shifts. 2 questions are addressed: will the new lifecourse migration patterns provide for a more deconcentrated redistribution of the baby-boom cohorts, both prior to and after their entry into the elderly age categories, than the lifecourse migration patterns followed by earlier cohorts; and will the new lifecourse distribution pattern lead, in the long run, to a significantly more deconcentrated distribution of the elderly population. The examination of these 2 questions focuses, largely, on redistribution across 9 broad regional and metropolitan area groupings defined on the basis of 3 census regions -- the North (combining the Northeast and Midwest census regions), the South, and the West -- and 3 categories of metropolitan status -- large metropolitan areas (those with 1980 populations exceeding 1 million), other metropolitan areas, and nonmetropolitan areas. The comparison of "new" versus "old" lifecourse migration patterns contrasts the census-based age-specific migration stream rates, registered over the 1975-80 period, with those registered over the 1965-70 period. Given the sharp and broad-based shift toward deconcentrated redistribution which characterized practically all segments of the population during the 1970s, it is assumed that the age-specific migration patterns observed over the 1975-80 period approximate the more deconcentrated redistribution tendencies which will be adopted by the baby-boom cohorts (and their successors) over the remainder of their lifecourse. The 1965-70 net migration rates point up the aggregate redistribution implications associated with the "old" lifecourse migration stream patterns. Among the rates for North large metropolitan areas, the only positive net migration is observed for the 25-29 age category; the greatest net outmigration rate is shown for the 65-69 age category. The rates for South nonmetropolitan areas are negative for all age categories under age 55, and most accentuated outmigration is shown during the young-adult years. The positive net migration exhibited for the older adult and post retirement ages reflects the low outmigration rates from nonmetropolitan areas during these ages and the slight peaking of immigration for these years. The results of this analysis imply that more attention should be devoted to migration, over the entirety of the lifecourse, in future studies of population redistribution.  相似文献   
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This study explores the effects of task structure and leader power on participative leadership across Australian, African, Papua-New Guinea and Pacific Island managers. Managers in all national groups are more participative in situations of low structure and low power than for high structure and high power, respectively. Participation in situations of low structure and low power declines in the order: Australia, Africa, Papua-New Guinea, Pacific Islands. It is argued that this effect is an instrumental effect of managerial education, rather than being culturally determined. the Vroom-Yetton leadership methodology is used to measure participation levels. Subjects are a total of 150 middle-level managers attending management education courses.  相似文献   
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Abstract: The working wife as a factor in the determination of family status has been universally ignored by students of stratification. In this plea for investigation, it is suggested that the employment or married women could affect the system of stratification in the following ways: (1) making possible greater access to symbols of status; (2) implying that the husband has been unsuccessful in his own career; (3) identifying the wife with a particular occupation; and (4) identifying certain occupations with wives of high status.  相似文献   
48.
The simulation problem is one of the most commonly used formats in computer-assisted instruction (CAI). In medical education, a patient simulation problem is known as a patient management problem (PMP). A number of computerized PMP systems are currently available. However, to date, there is no record of PMP systems having been developed using artificial intelligence. This is noteworthy since artificial intelligence techniques could help in the generation of more effective and intelligent instructional systems.

This paper analyzes and evaluates existing instructional simulation software in clinical medicine in terms of effective educational design attributes. Components of effective PMP systems thus identified are incorporated into a computerized instructional system which uses artificial intelligence techniques for teaching problem-solving and diagnostic skills to undergraduate medical students.  相似文献   

49.
Polyhedral combinatorics is a subarea of combinatorial optimization of increasing practical importance. It deals with the application of the theory of linear systems and linear algebra to combinatorial problems. The paper is not intended as a survey on polyhedral combinatorics but it reviews some of the main concepts and proof techniques.  相似文献   
50.
Summary In this paper it is investigated whether robust estimation procedures for the parameters of a regression model are also applicable when the observations are generated by the errors-in-variables model. Specifically, attention is paid to bounded-influence estimators, i.e. estimators that are constructed in such a way that the influence of a single observation on the outcome of the estimator is bounded. Both the classical errors-in-variables model and models with contaminated observational errors are considered.The authors are indebted to a referee for his valuable comments on an earlier version of this paper.  相似文献   
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