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981.
This paper analyzes the cost increases due to demand uncertainty in single-level MRP lot sizing on a rolling horizon. It is shown that forecast errors have a tremendous effect on the cost effectiveness of lot-sizing techniques even when these forecast errors are small. Moreover, the cost differences between different techniques become rather insignificant in the presence of forecast errors. Since most industrial firms face demand uncertainty to some extent, our findings may have important managerial implications. Various simulation experiments give insight into both the nature and the magnitude of the cost increases for different heuristics. Analytical results are developed for the constant-demand case with random noise and forecasting by exponential smoothing. It is also shown how optimal buffers can be obtained by use of a simple model. Although the analysis in this paper is restricted to simplified cases, the results merit further consideration and study. This paper is one of the first to inject forecast errors into MRP lot-sizing research. As such it attempts to deal with one of the major objections against the practical relevance of previous research in this area.  相似文献   
982.
This paper applies the patrol-initiated-activity hypercube queuing model to historical data from a police agency. The model allows servers to handle both calls assigned by a central dispatcher and activities initiated by the servers. By duplicating a fairly complex dispatch strategy, the model was found to predict both assigned and server-initiated work loads accurately for the overall system and individual servers. The model is apparently ineffective in predicting small unit-travel-time differences for this police agency.  相似文献   
983.
In this paper we incorporate a linear demand function to model the price-volume causal relationship into stochastic cost-volume-profit (CVP) analysis. We assume that the objective function is to maximize expected profit; other objective functions are also discussed and compared. A linear stochastic model follows from which probabilistic statements can be easily obtained if the random variables are assumed to be multivariate normal. The basic framework is shown to be a special case of project value maximization where project value is the cash flow of the project discounted for time and risk according to the capital asset pricing model. Moreover, an intertemporal extension that considers inventory is developed. In summary, a new approach to stochastic CVP analysis that incorporates the management decision process in an uncertain environment is developed.  相似文献   
984.
Livingston data on expected inflation rates have been used extensively in the financial literature, especially in investgating the relationship between nominal interest rates and expected inflation rates; however, the data have not been subjected to a thorough analysis of forecast accuracy. The objective of this paper is to analyze the forecast properties of Livingston data using a wide variety of time and frequency domain methods over an extended sample period and for selected subperiods.  相似文献   
985.
This paper reports the findings of a laboratory experiment designed to investigate the relationship of category width (CW) cognitive style with accountants' perceptions of accounting information. Subjects drawn from large accounting firms in Sydney, Brisbane, and Melbourne, Australia, were classified into broad, medium, and narrow categories following the test devised by Pettigrew [19]. Subjects were requested to state their level of confidence in decisions they had made after receiving (1) conventional accounting information or (2) conventional accounting information and human resources accounting (HRA) information using a one-group pretest-posttest design. The results indicated a significant relationship between CW cognitive style and the accountants' confidence in their decisions. Furthermore, CW cognitive style moderated the accounting-information/decision-making relationship.  相似文献   
986.
This paper is concerned with the dimensions and processes of dehumanization within the context of our contemporary social order. It considers briefly the nature of post-industrial society and its dehumanizing consequences, discussing the various dimensions of dehumanization articulated by various writers. The core argument is that dehumanization is created by external social structural conditions and only later becomes internally self-generating within the individual, which can lead to a self-perpetuating dehumanization syndrome.  相似文献   
987.
今天,日益增长的全球资本主义经济是一张复杂的动态的网络,这个网络由社会、文化以及反映我们个人和大众的意识的经济体制构成。随着意识创造并联结了所有事物这一观点被人们日渐认可,以及全球责任感的增强,资本主义经济体制可以切实地被改变,从而促进经济的长期繁荣。  相似文献   
988.
Clinical studies of children in international adoption reveal unique patterns of psychological adjustment to permanent family care. Pre‐adoption history often includes early object loss, medical and nutritional deprivation, multiple care‐giving disruptions, and the lack of primary care‐giving relationships. These factors and the age at the time of adoption are risks to positive emotional and cognitive development. Adoptive parents may be unprepared for the resulting developmental problems. Most significantly, parents and children are often at different points in readiness to establish an attachment relationship. The parents are eager to claim their child, but the child is unready to respond because of emotional fragility and lack of previous attachment experiences. Two clinical vignettes illustrate the importance of a developmental and medical framework in assessing the unique needs of these survivor children, as well as the necessity of an empathic therapeutic holding environment that can sustain the emerging family attachments under stress. The psychological impact of cross‐cultural adoption and traumatic early beginnings reverberates across time but with empathic parental care and treatment recovery can be significant.  相似文献   
989.
Unusual events, beyond mere coincidences, may occur during the course of psychotherapy. Yet, clinical training often does not prepare therapists how to understand and potentially engage with these encounters. The aim of this report is to explore the emergence of synchronistic events in therapy, while providing two clinical case composites to illustrate the author’s central points. Drawing on the Celtic concept of “thin places,” a new understanding of synchronicities and the therapeutic relationship is offered.  相似文献   
990.
Correspondence to Bruce A. Thyer, Ph.D., School of Social Work, The University of Georgia, Athens, G A 30602, USA. Summary Critics of applying conventional quantitative research methodsto the problems of social work practice research have ignoredthe considerable progress which has been achieved during thepast decade in scientifically documenting the effectivenessof social services. A set of First Principles of Practice Researchis outlined for use by researchers in the design and conductof practice research, and for use by the consumers of researchto evaluate the methodological rigour of practice experiments.The advocates of qualitative research are urged to provide theprofession with similar positive examples of research on theoutcomes of social work practice, and to develop explicit guide-linesfor the conduct of qualitative studies.  相似文献   
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