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991.
An important issue in planning capacity expansion under uncertain demand is the effect of lead time on the timing of plant construction. Our model helps decide whether (1) plant construction is initiated after a certain deficit is accumulated, or (2) plant construction is initiated ahead of demand when a certain capacity surplus is reached. In addition to our analytical results, we present computational results to show that it is economically attractive to delay plant construction beyond the time when existing excess capacity becomes fully absorbed, with relatively short construction lead time. 相似文献
992.
993.
Marketing communication intensity (i.e., the ratio of advertising and promotional expenditures to sales) has been an important topic for both business managers and academics. Here, we investigate cross-sectional and time-series variation of communication intensity due to: type of offering (product versus service) and type of market (consumer versus industrial). Overall, we find that both of these factors affect variation of communication intensity across industries and over time. However, the effect of market type is much more dramatic than the effect of offering type. Such knowledge about patterns in communication intensity levels helps managers make decisions about how much to spend on advertising and promotion. 相似文献
994.
In this study the potential performance benefits of easy goals were examined within the multiple cue probability learning paradigm (MCPLP). Specifically, the effects of varying levels of goal difficulty on performance and risk propensity (used to define a form of commitment) were investigated. With few exceptions, previous studies demonstrated support for difficult goals. In this study, contrary to the majority of past evidence, as goals became easier decision quality significantly improved. Moreover, risk propensity increased with easier goals and, as suggested by a post-hoc analysis, had more direct impact on decision makers’ behaviors than goal levels. Goal-related behavior in complex MCPLP tasks appears to significantly differ from the majority of goal evidence in other types of research due to the tendency for subjects to view complex task properties in the same context as goal levels. 相似文献
995.
In an earlier paper [11], the problems of rank reversals and invalid composite priorities in AHP were addressed by modifications to the AHP procedure. That solution was subsequently criticized [5]. In this paper, we rebut these criticisms, and we show how rank reversals in AHP can arise merely from the process of normalizing local priorities. 相似文献
996.
Constrained forecasting has become a popular approach to the complex task of predicting future sales. Mixed performance results have been obtained by companies employing constrained forecasting systems software packages which probably reflects the lack of any clear system implementation guidelines. A number of important operational parameters such as the number of product families, criterion used to define product families, number of system levels, etc. must be specified. This study reports on an investigation of two of these parameters: product group size and appropriate grouping criterion. Different tests are performed with the constrained forecasting system and compared to a traditional forecasting approach using product data from the Cummins Engine Company of Columbus, Indiana. 相似文献
997.
This study revisits the traditional single stage, multi-item, capacitated lot-sizing problem (CLSP) with a new integrative focus on problem structuring. Unlike past research, we develop integrative cycle scheduling approaches which simultaneously address lot-sizing, capacity, and sequencing issues. Our purposes are to (1) explore the effect of sequencing on inventory levels, (2) examine the problem of infeasibility in the economic lot scheduling problem (ELSP), and (3) provide a simple methodology of generating low-cost cycle schedules in an environment with discrete shipping, dynamic demands, limited capacity, zero setup cost, and sequence-independent setup times. Our procedures are compared to benchmark cycle scheduling approaches in terms of both inventory cost and computation time under different demand scenarios, using the operating data from a flexible assembly system (FAS) at the Ford Motor Company's Sandusky, Ohio plant. 相似文献
998.
一刘智的《天方性理》是18世纪和19世纪期间中国穆斯林最为广泛阅读的书之一,但该书后来逐渐为某些穆斯林学者所批评。批评此书的穆斯林学者认为,它从真正的伊斯兰教那里走岔了道。即便在今天,那些读此书的穆斯林或非穆斯林们都为这样的事实所触动,即它与通常描述的伊斯兰教义不完全相像。他们多半会问:这本书如何谈论伊斯兰教的呢?哪些地方被认为是穆斯林的内容呢?比如从《古兰经》、先知穆罕默德和大权威作家那里引用的内容在哪里?礼仪的教导、教规和制度、穆斯林信仰的认主学阐述又在哪里呢?为什么会有如此多的新儒家专用术语?从笔者这方… 相似文献
999.
1000.
Sarah A. Font Elizabeth T. Gershoff 《Social policy report / Society for Research in Child Development》2020,33(3):1-40
Foster care provides round-the-clock substitute care for nearly 700,000 U.S. children who are temporarily or permanently separated from their family of origin each year. Each state manages its own foster care system according to federal regulations. Despite numerous large-scale federal policy reforms over the past several decades, substantial concerns remain about the experiences and outcomes of children in the foster care system. The most recent effort to reform foster care, the Family First Prevention Services Act of 2018, attempts to both reduce the use of foster care and increase the quality of care. In this report, we review how policy has shaped the experiences and outcomes of children in foster care, where policy has succeeded, and where it falls short of achieving its goals. We then identify opportunities for federal and state policy to better support the safety, health, and well-being of children in foster care. 相似文献