Optimal ordering policies for deteriorating items using a discounted cash-flow analysis when a trade credit is linked to order quantity

In today’s competitive market, in order to obtain a competition advantage, the supplier often offers the purchaser a longer permissible delay in payments or a price discount if the order quantity is greater than or equal to a predetermined quantity. As a result, in this paper, we establish an inventory model for the purchaser in which the supplier provides different trade credits. We then solve the inventory problem by using a discounted cash-flow (DCF) approach, characterize the optimal solution, and obtain some theoretical results to find the optimal order quantity and the optimal replenishment time. Finally, we provide several numerical examples to illustrate the results.     

Joint shipment consolidation and inventory decisions in a two-stage distribution system

This study is motivated by a problem that an industrial distributorship faced while distributing automotive spare parts to service and repair centers. Considering the problem encountered, we present an analytical model for joint inventory and shipment consolidation decisions in a two-stage distribution system with a single distribution center, multiple non-identical retailers, and an outside supplier. The retailers face stochastic end-customer demand and use continuous review to replenish inventories. On the other hand, the distribution center uses a periodic review policy and employs a time-based shipment consolidation policy to dispatch retailers’ accumulated orders at the end of each consolidation cycle. We present an exact optimization technique to compute the optimal replenishment quantity at the distribution center, order-up-to level at retailers, and a shipment consolidation cycle length to measure the effects of inventory at retailers on the overall performance. Finally, we perform numerical experiments to measure the impact of various parameters on the overall distribution system.     

Inventory write-down prediction for semiconductor manufacturing considering inventory age,accounting principle,and product structure with real settings

The International Financial Reporting Standards (IFRS) No. 2 has been the worldwide accounting principle for the reduction of inventory to market allowance since January 1, 2005. Using make-to-stock manufacturing strategies and inventory accounting for only approximately 14% of the total costs, integrated device manufacturers have found maintaining robust records for financial statements increasingly difficult. For example, one company in the case study conducted in this study must write-down losses of 2–100% of the total inventory costs for products with inventory ages of 18 months–3 years. However, the average cycle time for producing flash memory is approximately 3 months. In other words, when the system variation and safety stock policy are considered, the company must write-down the reduction of inventory to market allowance for most of work-in-process inventory. However, little research has been done to addressing the practical management of operations according to inventory aging processes. This study develops a polynomial-time-based model to obtain significant features, including inventory ages, accounting principles, and product structures (bill of material), for the accurate prediction of inventory write-downs to reduce the impact of the carrying value fluctuation of inventory. An empirical study was conducted on a Taiwanese semiconductor manufacturer. The results show that predicting 3-month inventory write-downs of a complete flash memory production line comprising approximately 8500 product types can be conducted in less than 10 s, with the mean absolute percentage error (MAPE) less than 3.5%. Discussions regarding the sensitivity analysis and cost tornado diagrams suggest the priority of affecting factors. The results show the viability of implementing the proposed model to predict inventory write-downs in the semiconductor manufacturing industry.     

库存路径问题及其最新进展

在分析库存路径问题(IRP)相关文献基础上,给出了IRP的一般化定义,并对其进行分类。从拓扑结构、计划期、客户需求、供应能力、补货策略、配送模式等方面阐明了IRP的特征属性的描述方法。最后重点总结了2000年以来IRP研究文献的建模及求解方法,对比国内外研究进展,指出目前的求解算法研究已经很充足,继续研究应该拓展IRP问题本身。     

Production-inventory policy for a deteriorating item with a single vendor-buyer system

In this paper, production-inventory models for a deteriorating item in a single vendor-buyer system has been developed with constant production and demand rate. Shortages at the buyer (when it is allowed) depends on time. The models have been formulated as cost minimization problem via both integrated and non-integrated approaches and solved using genetic algorithms developed to solve the single and multiobjective production inventory problems. Numerical illustrations of the models have been presented and the sensitivity analysis with respect to rates of production, demand and deterioration are performed.     

Monitoring land use and cover around parks: A conceptual approach

Many of the habitats and resources which influence ecological functioning within National Parks, and protected areas in general, are located outside of their borders in unprotected areas. Hence, land use and land cover changes in surrounding areas may substantially influence the natural resources within parks. The US National Park Service has recognized these threats and incorporated land use and land cover monitoring into its Inventory and Monitoring Program. The purpose of this paper is to provide a framework based on a conceptual approach for planning and implementing monitoring within this Program. We present a conceptual model, based on ecological theory, which illustrates how land use and land cover change impact park resources, and helps to identify monitoring indicators that will measure relevant attributes of land use and land cover change. We also discuss potential sources of data for quantifying indicators of land use and land cover change over time, including remote sensing data and ancillary spatial datasets. Finally, we describe steps for analyzing monitoring data so that the intensity and direction of changes in land use and land cover over time are quantified, as well as trends in the status of important park resources impacted by these changes. Integration of land use and land cover monitoring data and park resource data will allow for analysis of change from past to present, and can be used to project trends into the future to provide knowledge about potential land use and land cover change scenarios and ecological impacts. We illustrate our monitoring approach with an example from the Inventory and Monitoring Program's Greater Yellowstone Network.     

物料需求计划与准时生产制的对比分析

本文对西方的物料需求计划(MRP)和日本的准时生产制(JIT)这两种生产管理控制方法的产生背景、构成要素、运行机制及性能进行了对比。综述了将二者结合起来的混合控制策略的研究情况。探讨了不同控制策略在计算机集成制造系统中与制造过程集成的可能性。并结合中国国情,分析了混合控制策略的应用前景。     

股份公司两“准备”核算中存在问题及改进建议

本文对《股份有限公司会计制度—会计科目和会计报表》中“坏帐准备”、“存货跌价准备”会计科目核算规定中存在的问题进行了探讨 ,并提出了改进建议。     

降低备件消耗 合理规范备件储备

本文根据近年来我公司备件的消耗及库存情况,分析了备件消耗逐年增高,库存偏高的原因,提出了备件管理降耗利库的合理性措施.     

矿山企业物资管理存在的问题、成因及对策

我国矿山的物资管理由于受计划经济和自然环境的影响 ,普遍存在着管理水平较低、管理手段滞后、无效消耗偏大、物资积压严重、资金周转缓慢等问题。因此 ,探索当前矿山企业的物资管理对降低物资消耗 ,提高企业的生产率和市场竞争力有着显而易见的作用。