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991.
992.
研究市场需求和生产成本同时扰动时非线性需求供应链的最优应对策略.首先在稳定条件下提出供应链的收益共享协调合约;生产成本和需求扰动会导致原有的收益共享合约不再协调,提出了供应链在一体化决策时应对双因素同时发生扰动的最优策略;进一步提出了改进的收益共享合约协调分散化决策的供应链系统.最后运用数值实验对模型进行了验证. 相似文献
993.
光管理是提高晶体硅太阳能电池光吸收和短路电流(Jsc)进而提高转换效率的重要因素之一。本文回顾了最常见的光管理方式,包括表面抗反射、散射以及陷光等。为了降低晶体硅电池的表面反射损失,开发了多种表面抗反射结构。例如,仿生蛾眼结构利用渐变折射率实现了宽光谱低反射率,其表面反射率可达1%以下。随着晶体硅电池衬底减薄,光管理要求更加严格,除了在更宽波长范围内达到超低反射率外,还需要在更高的入射角范围内实现低反射率。此外,利用前表面散射以及背表面陷光结构提高红外光的吸收光程对于晶体硅电池特别是薄衬底晶体硅电池的有效光吸收具有重要意义。 相似文献
994.
995.
Recent progress concerning experimental and numerical methods for practical investigations of vehicle soiling are reviewed in this paper. Wind tunnel tests and available measurement techniques are analyzed and compared with respect to their possible applications and to the results they may deliver. Different computational models for liquid films generated by spray impingement on vehicle surfaces are then considered. Models relying either on a dispersed or on a continuous approach are compared, resulting advantages and shortcomings are discussed. It is finally shown that, in spite of considerable progress during the last years, substantial work remains to be done in order to capture the complexity of real film flow dynamics for an accurate representation of wetting processes, film separation and break-up interacting with turbulent flows. 相似文献
996.
In this paper, we derive an optimal ordering policy for an unreliable newsboy who can place two sequential orders before the start of a single selling season by using a demand forecast update. Supply yield is modeled using a uniform distribution considering both the minimum order guarantee and the maximum yield. Our results indicate that a firm should focus on increasing the minimum order guarantee from a first stage supplier to reduce its total supply chain cost. 相似文献
997.
M. Ali Khan 《Nonlinear Analysis: Theory, Methods & Applications》2011,74(1):171-181
In recent work, the authors set classical turnpike theory in the context of the economics of forestry, as developed by Mitra and Wan, and presented two far-reaching results. In this paper, we present a conceptual generalization that takes this theory and configures it around a set in the space of forest configurations rather than around the golden-rule forest configuration. Our set-valued analysis hinges on periodicity and yields the earlier results as corollaries under a non-interiority condition on the felicity function that shrinks the set to the point. The question that we pose, and answer, has obvious relevance to more general contexts and, in particular, to turnpike theory as developed by Samuelson, Gale, McKenzie, and their followers. 相似文献
998.
999.
In this paper, we review the contributions to date for analyzing the newsvendor problem. Our focus is on examining the specific extensions for analyzing this problem in the context of modeling customer demand, supplier costs, and the buyer risk profile. More specifically, we analyze the impact of market price, marketing effort, and stocking quantity on customer demand; how supplier prices can serve as a coordination mechanism in a supply chain setting; integrating alternative supplier pricing policies within the newsvendor framework; and how the buyer’s risk profile moderates the newsvendor order quantity decision. For each of these areas, we summarize the current literature and develop extensions. Finally, we also propose directions for future research. 相似文献
1000.
Richard Pibernik Yingying Zhang Florian Kerschbaum Axel Schröpfer 《European Journal of Operational Research》2011
It is a well-acknowledged fact that collaboration between different members of a supply chain yields a significant potential to increase overall supply chain performance. Sharing private information has been identified as prerequisite for collaboration and, at the same time, as one of its major obstacles. One potential avenue for overcoming this obstacle is Secure Multi-Party Computation (SMC). SMC is a cryptographic technique that enables the computation of any (well-defined) mathematical function by a number of parties without any party having to disclose its input to another party. In this paper, we show how SMC can be successfully employed to enable joint decision-making and benefit sharing in a simple supply chain setting. We develop secure protocols for implementing the well-known “Joint Economic Lot Size (JELS) Model” with benefit sharing in such a way that none of the parties involved has to disclose any private (cost and capacity) data. Thereupon, we show that although computation of the model’s outputs can be performed securely, the approach still faces practical limitations. These limitations are caused by the potential of “inverse optimization”, i.e., a party can infer another party’s private data from the output of a collaborative planning scheme even if the computation is performed in a secure fashion. We provide a detailed analysis of “inverse optimization” potentials and introduce the notion of “stochastic security”, a novel approach to assess the additional information a party may learn from joint computation and benefit sharing. Based on our definition of “stochastic security” we propose a stochastic benefit sharing rule, develop a secure protocol for this benefit sharing rule, and assess under which conditions stochastic benefit sharing can guarantee secure collaboration. 相似文献