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151.
Some countries are importers while others are exporters of global backbone connectivity. At the same time, input components such as local access are non-traded. This paper analyzes a non-cooperative regulatory game between importing and exporting countries, assuming that the prices of both traded and non-traded inputs can be regulated. We show that exporting countries choose a more restrictive regulation of non-traded goods than importing countries do. We further show that a requirement of international non-discrimination may hurt importing countries, and give firms producing traded inputs incentives to invest in quality degradation.  相似文献   
152.
Material requirements planning (MRP) is a planning and information system that has widespread application in discrete-parts manufacturing. The purpose of this article is to introduce ideas that can improve the flow of material through complex manufacturing systems operating under MRP, and that can increase the applicability of MRP within diverse manufacturing environments.MRP models the flow of material by assuming that items flow from work station to work station in the same batches that are used in production. That is, once work starts on a batch of a certain item at a certain work station, the entire batch will be produced before any part of the batch will be transported to the next work station on its routing plan. Clearly, efficiency can be increased if some parallelism can be introduced. The form of parallelism investigated here is overlapping operations.Overlapping operations occurs when the transportation of partial batches to a downstream work station is allowed while work proceeds to complete the batch at the upstream work station. The potential efficiencies to be gained are the following:
• Reduced work-in-process inventory
• Reduced floor space requirements
• Reduced size of transfer vehicles
Additional costs may accrue through additional cost of transportation of partial batches and through additional costs of control.Some MRP software vendors provide the data processing capability for overlapping operations. However, the user is given little or no guidance on overlapping percentages or amounts. It is our intent to provide a simple, robust technique to MRP users who would like to overlap operations and gain some or all of the above efficiencies.An optimal lot-sizing technique is derived by considering a generic two work station segment of a manufacturing system. Under the assumptions of constant demand and identical production rates, a cost function that considers setup costs, inventory holding costs and transportation costs is derived. This cost function is minimized subject to the constraint that the production batch is an integer multiple of the transfer batch. We solve for the optimal production batch, the optimal transfer batch, and the integer number relating them. Solutions are obtained as closed form, easy to-evaluate formulas.By introducing more parallelism, overlapping operations can reduce lead time. However, this will not happen without modification of MRP logic to accommodate such reduced lead time. We derive a formula that shows how a significant lead time compression can easily be obtained and implemented in MRP.We consider an example to illustrate the application of the technique on typical data from the electronics industry. The outcome showed a cost savings of approximately 22.5% over the standard MRP approach.Overlapping operations allows the applicability of MRP to an increasing number of situations that are not modeled faithfully by conventional MRP logic. Three such situations that occur often are the following:
• Limited size of transfer vehicles dictate that several transfers should be planned.
• Lead time requirements prohibit nonoverlapped operations.
Our analysis suggests how to accommodate these difficult practical situations into MRP.Overlapping operations in material requirements planning provides an enhancement that allows wider applicability, shortened lead times, and lower total costs. It may be applied selectively to any two work stations where it is deemed appropriate. Due to the structure of the cost function, it is possible to make the transfer lot-sizing decisions independent of the production lot-sizing decisions. Therefore, significant improvements can be made through overlapping with minimum disruption to the existing MRP system machinery. It is our conviction that overlapping operations is an important concept that can and will impact MRP. We suggest the approach presented here as a systematic way to implement overlapping.  相似文献   
153.
在很大程度上,华尔街推动了美国从一个原始而单一的经济体成长为一个强大而复杂的经济体。在美国经济发展的每一个阶段中,以华尔街为代表的美国资本市场都扮演着重要的角色。  相似文献   
154.
Summary We consider both Nash and strong Nash implementation of various matching rules for college admissions problems. We show that all such rules are supersolutions of the stable rule. Among these rules the lower bound stable rule is implementable in both senses. The upper bound Pareto and individually rational rule is strong Nash implementable yet it is not Nash implementable. Two corollaries of interest are the stable rule is the minimal (Nash or strong Nash) implementable solution that is Pareto optimal and individually rational, and the stable rule is the minimal (Nash or strong Nash) implementable extension of any of its subsolutions.We wish to thank Professor William Thomson for his efforts in supervision as well as his useful suggestions. We are grateful to the participants in his reading class, workshops at Bilkent University, University of Rochester, and in particular Jeffrey Banks, Stephen Ching, Bhaskar Dutta, Rangarajan Sundaram and an anonymous referee for their helpful comments.  相似文献   
155.
This paper examines the effects of a marginal change in uncertainty on resource allocation and factor rewards by relaxing the assumption of factor inelasticity. We demonstrate that integrating a variable labor supply into Batra's two-sector uncertainty model can mitigate or reverse many of the earlier results. Specifically, a marginal increase in uncertainty may trigger the resource to move from the certainty sector to the uncertainty sector in the presence of a backward-bending labor supply curve.  相似文献   
156.
Since the Asian financial crisis of the late 1990's, there have been numerous calls for the reform of East Asian corporate governance. Without reform, fears abound that the crisis will return. However, a baseline understanding of corporate governance in East Asia needs to be established before reform efforts can begin. In the West, three major functions of boards are commonly recognized: resource dependence, service, and control. These functions have yet to be examined in the context of boards of directors of Overseas Chinese firms in East Asia. In this exploratory study, we examine the extent to which these functions are performed, primarily by outside board members, in Overseas Chinese firms in Hong Kong and Taiwan. We find that the service and control functions are less pronounced for East Asian boards than what would be expected in the West, while the resource dependence function is more pronounced. We also findthat the governance of the region is being moved closer to international practices by a new generation of leaders that have been exposed to Western influences and intense global competition. The implications of our findings for managers, educators, and researchers are discussed.  相似文献   
157.
What are the limits of collective action? As James Buchanan famously worried, is it possible to empower the productive state without lapsing into the predatory state? This paper uses insights from F.A. Hayek to address problems of public goods and the role of the state. Hayek convincingly argued that no central planner has sufficient knowledge to run an economy. Yet Hayek also allowed for state provision of some goods beyond the prevention of coercion. The question, then, is whether Hayek’s safeguards offer a satisfactory response to Buchanan’s worry. This paper contends that Hayek violated his own conditions for permissible government activity. Nevertheless, he offers a serious research agenda for limiting state abuses.  相似文献   
158.
159.
In a recent paper, Jones and Zydiak [2] discuss the steady state fleet design problem, which has no natural initial distribution of vehicles. For this problem, they develop a new optimality criterion of minimizing annual equivalent cost per vehicle because the traditional optimally criterion of minimizing annual equivalent cost can lead to paradoxical results, as shown by example, when applied to the fleet design problem. In a subsequent note, Hartman [1] argues that this paradox is actually a result of a replacement convention that ignores opportunity costs. In this response, we demonstrate that paradoxical replacement behavior can occur with the traditional criterion even when opportunity costs are accounted for in the replacement analysis. We further conclude that the problems considered respectively by Jones and Zydiak [2] and Hartman [1] are fundamentally different in nature.  相似文献   
160.
Information technology has always played an important role in the services sector of the U.S. economy. In recent years, however, services industries have stepped up their acquisitions of computers, telecommunications equipment, and other such products dramatically. As a result, the broad segment of the economy that can be classified as services providers now owns about 84% of the total U.S. stock of information technology items. Moreover, relative to goods-producing industries, a much larger proportion of the services sector's capital budgets is spent on information technology, revealing a significantly greater dependence by services on such technology as a factor of production. This reliance underscores technology's strategic importance in the United States' competitive challenge. With services now the predominant mode of economic activity in the United States, a productivity payback from information technology is absolutely essential to keep the economy on a longer term path of sustainable growth.So far, the services sector has little to show for its spending binge on technology. Quite simply, massive investments in information technology have failed to boost national productivity growth in the present decade. Furthermore, with manufacturing productivity now on the rebound, problems in the services sector loom increasingly large in the United States' broader competitive struggle. It is certainly not too late. New and creative applications of information technology could still enhance the productivity performance of the services sector's predominantly white-collar work force. Until that payback begins to occur, however, the role of technology spending will be under growing suspicion [3, 8, 9].In what follows, an attempt is made to provide a detailed industry-by-industry assessment of services sector spending on information technology. By way of background, the broad contours of capital formation in services industries are first examined over the post-World War II era.  相似文献   
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