CROSS‐DOCKING AND ITS IMPLICATIONS IN LOCATION‐DISTRIBUTION SYSTEMS

Cross‐docking replaces traditional warehousing, enabling continuous flow of items without storage. Here we model location‐distribution networks, that include cross‐docking facilities, to obtain the latter's impact on the supply chain. We formulate optimization models to minimize total cost in three multi‐echelon networks, each model generalizing the preceding one. The first includes a single manufacturer, one product type, and multiple customers. Cross‐docks are to be located between origin and destinations. Besides solving optimally, a tool for quantitative analysis of direct‐shipment decisions is developed. The second model considers more than one product: We determine a cost‐effective sequence of items for indirect shipment (via cross‐docks). Finally, in a network with multiple origins, optimal solutions are obtained for 40 medium‐sized and larger examples.     

EXPRESSING INVENTORY CONTROL POLICY IN THE TURNOVER CURVE

Estimation of the inventory level for an entire class of items is a valuable time saver when control of inventories at the aggregate level, rather than the item level, is of interest. Inventory approximation by location in supply chain network configuration and evaluation of inventory control policy shifts, are two examples of application. In this article, various popular inventory policies are related to a general function known as an inventory turnover curve that expresses inventory levels from the combined demand of multiple items. By knowing some basic item characteristics of representative items in a product class, the type of inventory policy being used, and the current aggregate inventory level, an inventory turnover curve can be constructed. This resulting turnover curve can be used to estimate inventory levels within 4.6%, on the average, of theoretically predicted ones.     

Symmetry and order in the portfolio allocation problem

Summary. This research studies the role of multivariate distribution structures on random asset returns in determining the optimal allocation vector for an expected utility maximizer. All our conclusions pertain for the set of risk averters. By carefully disturbing symmetry in the distribution of the, possibly covarying, returns, we ascertain the ordinal structure of the optimized allocation vector. Rank order of allocations is also established when a permutation symmetric random vector is mapped into the returns vector through location and scale shifts. It is shown that increased dispersion in the vectors of location and scale parameters benefit, ex-ante, investors as does a decrease in the rank correlation coefficient between the location and scale parameter vectors. Revealed preference comparative static results are identified for the location and scale vectors of asset returns. For most issues addressed, we arrive at much stronger inferences when a safe asset is available. Received: August 8, 2000; revised version: January 8, 2001     

Analysing Materials and Energy Flows in an Industrial District using an Enterprise Input–Output Model

Recent approaches to sustainable development leave much room for policies at a local level. In fact, it is becoming evident that targets such as increasing resource productivity, preserving natural cycles, or extending the present level of welfare, are best pursued within the confines of a local area. In particular, environmental changes are best brought about by considering local systems of firms as cornerstones of cooperative strategies and using data on materials and energy use in physical terms. In this paper, an enterprise input–output model is developed for an industrial district, i.e. a local group of firms specialized in the production of a single final output. The model allows for a detailed quantitative analysis of materials and energy flows and the consequent generation of waste and pollution. As a planning tool, the model may be used to evaluate alternative scenarios, such as the possibility of re- using waste taking account of sustainability requirements. An empirical case study applies the model to an industrial district in Southern Italy producing leather sofas.     

Spatial determinants of Japanese FDI in China

Research on foreign direct investment in China has spawned an increasingly large literature. Whilst regional cleavages with respect to the distribution of foreign direct investment (FDI) are acknowledged, empirical research on the spatial determinants of FDI in China has been limited. Furthermore, research on the spatial determinants of home country FDI in China has thus far been neglected due to difficulties in accessing the appropriate data. The objective of this paper is to examine the spatial determinants of Japanese direct investment in China by using an econometric model. To that purpose, a dataset is created from the Toyo Keizai directory on the overseas activities of Japanese companies. The results show that tertiary education, inland waterways, as well as coastal location are positive and significant determinants of Japanese investment in China.     

PLANNING MULTIPLE LOCATION INVENTORIES

Supplying customer demand from comparable alternate inventory locations when an item is out of stock at its primary stocking point creates a virtual inventory for that item. The expectation is that if more inventories can be drawn upon, the inventory for an item would be lower, the fill rate would be higher, or both. While generally true that safety stocks will be lower, regular stocks, on the other hand, may rise with such cross filling of demand. In this study, a methodology is developed that balances the cross filling effects on both regular and safety stocks for determining whether an inventoried item should be cross‐filled. An example and guidelines are given to show how the methodology can be simplified and applied in practice.     

Planning food services for a campus setting

Providing appropriate food services in a campus setting is increasingly important due to more demanding customers and because clients have less time to go off-campus when they need to eat. Using a university campus as an example, this research looks at customer satisfaction with existing food services and explores various methods for determining where to locate new facilities. This campus currently has great needs for additional food services, and it is shown clearly where additional food services are required. Also, the methods used are compared in terms of their effectiveness in finding the solution.     

中国外商直接投资的区位决定因素分析:城市数据

本文以全国210个地级以上城市为对象,分析了外商直接投资的区位决定因素。本文采用OLS和逐步回归分析方法以及2002年的横截面数据,在以往研究的基础上选择四项区位决定因素包括三种成本因素、三种市场因素、四种集聚因素和四种制度因素进行实证研究。结果表明,劳动力成本对各城市的外商直接投资的区位选择影响不明显,而市场规模、基础设施、教育和研究开发条件以及地方金融规模对外商直接投资的区位选择的影响具有显著性。本文的逐步回归分析结果还表明,就东部地区而言,能源条件和市场规模是较重要的区位决定因素;就中西部地区而言,市场规模、基础设施、教育和研究开发条件以及地方金融成为较重要的区位决定因素。     

Multilateral Comparison of Cost Structures in the Input–Output Tables of Japan,the US and West Germany

This paper presents a multilateral comparison of relative levels and structures of costs of production in Japan, the US and West Germany. The analysis is carried out by using harmonized input–output tables, which are converted at US prices by using adjusted sectoral purchasing power parities. A new accounting methodology is derived from recent developments of index number theory, whereas the chosen multilateral comparison procedure gives results that are invariant with respect to the order of the pairs of countries examined.     

Production-location decision and free entry oligopoly: A correction

This paper shows that there is no interior solution in Mai–Hwang's 1992 oligopolistic location model with free entry when the production function exhibits constant or decreasing returns to scale. The comparative static results of the impact of a demand change on the location decision only apply to the case where the production function exhibits increasing returns to scale. It re-examines the impact of a demand change on the location decision of an oligopolistic firm and corrects the propositions derived by [C.C. Mai, H. Hwang, Production-location decision and free entry oligopoly, Journal of Urban Economics 33 (1992) 252–271. Reprinted in: M.L. Greenhut, G. Norman (Eds.), The Economics of Location, vol. I: Location Theory, Edward Elgar, Aldershot, 1995].