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131.
Basic characteristics of an assemble-to-order environment make effective master scheduling extremely difficult. Limited resource capacities and dynamic customer end-item demand contribute to the complexity of the master production scheduling problem. To gain flexibility and responsiveness within this system, the master production schedule (MPS) focuses at the component level. This research proposes a master scheduling technique for manufactured components which combines a multiobjective capacitated multi-item/multi-stage lot-sizing model with an interactive multiple objective optimization solution procedure. To evaluate the model's performance as a realistic and practical master scheduling tool, this study focuses on the National Cash Register (NCR) electronics manufacturing facility in Columbia, South Carolina.  相似文献   
132.
Few studies of just-in-time (JIT) implementation examine their significance in make-to-order manufacturing environments. This study examines the relative importance of several operating variables that are characteristic features of JIT systems within such environments in North America. The results suggest that the most salient features of JIT for make-to-order and assemble-to-order firms are the elimination of waste (in the form of time and defects), reduced setup time, reduced lotsize, and a smaller pool of suppliers. In addition, the results suggest that the use of non-domestic suppliers can possibly hinder efforts at JIT implementation of materials procurement.  相似文献   
133.
The purpose of this study is to examine the reliability of the skin tone measures in the widely used American National Election Studies data collection (AN  相似文献   
134.
To meet the [African] crisis one must turn to agricultural-led growth. But, based on historical experience, an agricultural-led strategy must be framed in no less than a twenty-year horizon and must entail a combination of technological innovation, policy reform, and institutional restructuring because each, by itself, is limited. (Eicher, 1989)  相似文献   
135.
精明的商业领袖会在冲突中寻找创造价值的时机无论在哪一行,总会有争吵。未按时交货;客户改变主意;合作伙伴不遵守承诺;部门的主管不批准某项预算而且还进行人身攻击。经理们对待这样的冲突和对待其他生意的方式往往是不同的。他们的做法完全不同,就好像解决冲突需要完全不同的方式:要不你获胜,要不我获胜。双  相似文献   
136.
Graphical representation of survival curves is often used to illustrate associations between exposures and time-to-event outcomes. However, when exposures are time-dependent, calculation of survival probabilities is not straightforward. Our aim was to develop a method to estimate time-dependent survival probabilities and represent them graphically. Cox models with time-dependent indicators to represent state changes were fitted, and survival probabilities were plotted using pre-specified times of state changes. Time-varying hazard ratios for the state change were also explored. The method was applied to data from the Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL). Survival curves showing a ‘split’ at a pre-specified time t allow for the qualitative comparison of survival probabilities between patients with similar baseline covariates who do and do not experience a state change at time t. Time since state change interactions can be visually represented to reflect changing hazard ratios over time. A2ALL study results showed differences in survival probabilities among those who did not receive a transplant, received a living donor transplant, and received a deceased donor transplant. These graphical representations of survival curves with time-dependent indicators improve upon previous methods and allow for clinically meaningful interpretation.  相似文献   
137.
138.
Urban Ecosystems - The urban landscape constitutes a key aspect of human - nature interactions, as more than 60% of the world’s population resides in cities and their suburbs. This study...  相似文献   
139.
The theory of family welfare effort is a leading macro‐sociological explanation of variation in human fertility. It holds that states which provide universally available, inexpensive, high‐quality day care, generous parental leave, and flexible work schedules lower the opportunity cost of motherhood. They thus enable women, especially those in lower socioeconomic strata, to have the number of babies they want. A considerable body of research supports this theory. However, it is based almost exclusively on analyses of Western European and North American countries. This paper examines the Israeli case because Israel's total fertility rate is anomalously high given its family welfare effort. Based on a review of the relevant literature and a reanalysis of data from various published sources, it explains the country's unusually high total fertility rate as the product of (1) religious and nationalistic sentiment that is heightened by the Jewish population's perception of a demographic threat in the form of a burgeoning Palestinian population and (2) the state's resulting support for pro‐natal policies, including the world's most extensive in vitro fertilization (IVF) system. The paper also suggests that Israel's IVF policy may not be in harmony with the interests of many women insofar as even women with an extremely low likelihood of becoming pregnant are encouraged to undergo the often lengthy, emotionally and physically painful, and risky process of IVF.  相似文献   
140.
In recent decades, risk prediction has proliferated in the penal realm. Risk instruments currently guide an array of correctional decisions—such as participation in diversion programs, the provision of correctional services, and probation and parole supervision levels—and are being increasingly utilized or considered in pretrial detention and criminal sentencing. This article reviews empirical and theoretical accounts of the proliferation and effects of risk in the penal realm and also reflects on ongoing debates about the promises and perils of risk. Risk techniques have impacted the practices, discourses, and logics of punishment. Yet they have not triggered the abandonment of rehabilitative approaches (or retributive ones), nor have they replaced human judgment with a rationalized utopia or iron cage. This article also offers several interventions that complicate and further our understandings of risk. First, it highlights the complex entanglements between, on the one hand, actuarial and algorithmic risk instruments and, on the other, subjective, moral, and affective methods of evaluation. Second, it calls for increased attention to the performative effects of risk technologies: to the ways in which assessments not only report on but also create and alter the social world. The article concludes by reflecting on emerging topics and directions for future research.  相似文献   
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