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91.
It is common for subsidiaries of a group company to use the same types of components for producing similar products. Different subsidiary companies may well procure such components from the same suppliers. This paper studies two sourcing management models. One is the Subsidiary-Autonomous Sourcing Management (SD-ASM) where subsidiaries manage their inventories and place purchasing orders independent of each other. The other is the Headquarter-centered Common Sourcing Management (HQ-CSM) where purchasing orders of subsidiaries are processed centrally through some kind of headquarter coordination. In the SD-ASM model, each subsidiary places replenishment orders at a time interval corresponding to their economic order quantity (EOQ). In the HQ-CSM model, two purchasing order management policies are examined. One is the Order Coordination policy in which common replenishment epochs or time periods are proposed by the headquarter and the subsidiaries are encouraged to coordinate the timing of their orders based on the common replenishment epochs. The other is the Order Consolidation policy in which the subsidiaries combine the quantity of their orders and the headquarter places a combined order with the supplier. In the Order Coordination policy, classic RAND heuristic is used to find the best common replenishment epoch and the best replenishment timing of each subsidiary. In the Order Consolidation policy, the optimal order quantity of the combined order is obtained from a mathematical model. The combined order is then allocated to the subsidiaries according to a proportional allocation rule. A series of numerical studies is conducted to compare the costs of the SD-ASM and HQ-CSM policies. The results show that HQ-CSM outperforms SD-ASM in terms of cost and robustness against demand uncertainties. This achievement is largely due to the economies of process (synergistic ordering process), the economies of scale (large order quantity with price discount) and risk pooling effect (transshipments). The results also reveal that the Order Consolidation policy with a combined order always performs better than the Order Coordination policy with common replenishment epochs especially in face of high demand uncertainties and high service level in the global market. 相似文献
92.
生物质直燃发电厂燃料组织关键问题分析 总被引:1,自引:0,他引:1
生物质燃料资源的可供性是影响生物质发电厂生存和发展的根本问题,生物质发电厂燃料组织的关键在于燃料的收集、储存、运输等,文章结合柳城生物质直燃发电项目的开展,对生物质电厂燃料供应、储存、运输、价格控制等关键问题进行了分析,提出了解决的思路和方案. 相似文献
93.
ZHANG Guoyu SUN Tianxiang WANG Lingyun XU Xiping School of Photo-electronic Engineering Changchun University of Science Technology Changchun China 《机械工程学报(英文版)》2007,20(2):101-103
The system mathematical model of flexible 3D measuring system is built by theoretical analysis,and the theoretical formula for measuring space point coordinate is also derived. Frog-jumping based coordinate transform method is put forward in order to solve measuring problem for large size parts. The frog-jumping method is discussed,and the coordinate transform mathematical model is method of the space point coordinate compared to original value,and an advanced method is provided. Form the space point coordinate transform formula can derive the calculation measuring method for measuring large size parts. 相似文献
94.
随着我国现代化发展的不断加快,很多领域都使用高科技自动控制仪器.压力表的维修、安装与调试过程直接关系到工业生产,压力表的准确度对安全生产尤为重要,研究常见故障的维修技术是有效保证机械测量的准确性和可靠性.本文从影响压力表准确度的主要因素出发,着重介绍了压力表常见的一些故障,并且进行原因分析找出合理的维修处理方法,旨在不断提高压力表的准确度、操作水平和工艺. 相似文献
95.
吴亮 《皮革制作与环保科技》2021,2(5):22-22
随着工业生产和科学技术的迅猛发展,环境污染问题越发严重,严重影响了人们的生活质量.地表水是常见的一种水体形式,本研究探讨地表水监测存在的问题及改进方法,为改善环境污染提供参考. 相似文献
96.
靶场鉴定试验过程中产生不合格品是靶场试验所涉及的主要质量问题,其处理是靶场试验质量管理过程的一项重要工作内容,由于靶场质量体系文件中对不合格品的含义和不合格品产生后如何处理没有做出详细的规定,靶场参加试验的各岗位人员难以准确理解和正确执行,从而影响了对试验质量的判定和试验效率。因此,从理清不合格品的含义与分类出发,阐述了不合格品的审理机构组成、试验不合格品识别与审理、试验不合格品处置和纠正措施等,可为参加设计定型试验的靶场和相关单位参加试验人员提供参考。 相似文献
97.
GENERAL CAUCHY PROBLEM FOR THE LINEAR SHALLOW -WATER EQUATIONS ON AN EQUATORIAL BETA-PLANE 总被引:2,自引:2,他引:0
SHEN Chun SHI Wei-hui 《水动力学研究与进展(B辑)》2006,18(3):303-309
1. INTRODUCTION Over the last two decades, studies in the tropical meteorology and ocean have dramatically increased, such as the EI Nino/Southern Oscillation (ENSO), the large-scale heat-induced circulation of the tropical atmosphere and nonlinear effec… 相似文献
98.
BUSH JONES 《国际通用系统杂志》2013,42(1):63-68
The aim of the reconstruction problem is to determine from among all relevant structure systems those which allow us to reconstruct a given overall system to an acceptable degree of approximation. This paper considers a more general form of the reconstruction problem. Instead of restricting the reconstruction to structure systems, substates in general are allowed in the reconstruction. Furthermore, the overall system need not be known in its entirety to formulate a reconstruction. A very effective and efficient algorithm for this generalized reconstruction problem is presented. 相似文献
99.
One of the major design problems in the context of manufacturing systems is the well-known Buffer Allocation Problem (BAP). This problem arises from the cost involved in terms of space requirements on the production floor and the need to keep in mind the decoupling impact of buffers in increasing the throughput of the line. Production line designers often need to solve the Buffer Allocation Problem (BAP), but this can be difficult, especially for large production lines, because the task is currently highly time consuming. Designers would be interested in a tool that would rapidly provide the solution to the BAP, even if only a near optimal solution is found, especially when they have to make their decisions at an operational level (e.g. hours). For decisions at a strategic level (e.g. years), such a tool would provide preliminary results that would be useful, before attempting to find the optimal solution with a specific search algorithm. 相似文献
100.