Search Costs and Price Dispersion in a Localized,Homogeneous Product Market: Some Empirical Evidence

Convenience stores provide an opportunity to compare the price dispersion that occurs for gasoline, which is characterized by relatively low search and information costs to consumers, with that of in-store items, which are characterized by relatively high search and information costs to consumers. The results obtained from this study support the hypothesis that differences in search and information costs for consumers play a significant role in explaining the observed price dispersion that occurs for homogeneous items sold at convenience stores.     

First of the month effect: Does it apply across food retail channels?

In this study we use detailed daily scanner data on household food purchases to examine monthly food expenditure patterns across food retail channels. We compare food expenditure patterns in high and low-income households comparing those where Supplementary Nutrition Assistance (SNAP) is received in the first 10 days of the month versus households which receive SNAP over the first 15 days of the month. We find that food expenditure patterns vary systematically across the month within different retail channels by income and SNAP payment schedules. Low-income households in early SNAP distribution areas decrease their grocery and mass/club/superstore expenditures at the end of the calendar month and supplement this decrease with increased food expenditures in convenience stores and food away from home. Households in staggered SNAP payment areas show far fewer systematic patterns given the more distributed payment system.     

Ordering quantity decisions considering uncertainty in supply-chain logistics operations

This research seeks to determine the optimal order amount for a retailer given uncertainty in a supply-chain's logistics network due to unforeseeable disruption or various types of defects (e.g., shipping damage, missing parts and misplacing products). Mixture distribution models characterize problems from solitary failures and contingent events causing network to function ineffectively. The uncertainty in the number of good products successfully reaching distribution centers (DCs) and retail stores poses a challenge in deciding product-order amounts. Because the commonly used ordering plan developed for maximizing expected profits does not allow retailers to address concerns about contingencies; this research proposes two improved procedures with risk-averse characteristics towards low probability and high impact events. Several examples illustrate the impact of a DC's operation policies and model assumptions on a retailer's product-ordering plan and resulting sales profit.     

Automobiles: The Old Economy Collides with the New

The U.S. automobile industry is beginning to confront the next major technology – the internet. Business-to-business manufacturing systems and supply exchanges, together with business-to-consumer ordering and purchase systems, all have the potential to bring great efficiencies to this traditional industry. But each of these innovations raises new competitive issues. Internet ordering will greatly diminish the role of conventional dealers, who have thus far blunted its impact. B2B exchanges raise concerns about buyer power and other competitive effects. This paper outlines and analyzes these internet-drivenchanges and their competitive implications for the industry, its dealers, suppliers, and customers.     

A mixed-methods study of retail food waste in New Zealand

Little is known about the amount of food wasted in the retail sector. This study aimed to quantify retail food waste in New Zealand (NZ) and identify key drivers for food waste reduction, using a mixed-methods, observational study design that consisted of three parts: onsite food waste audits undertaken in 16 selected stores (complete data from 11 stores); semi-structured interviews with key retail staff from each store; and obtaining existing data from retailers. Retail food waste in NZ was estimated at 13 kg/capita/year for all food waste and diverted product (i.e. all food not sold or utilised at a retail level), which included 5 kg/capita/year designated as food waste (i.e. food directed to landfill, protein reprocessing and compost), with 3 kg/capita/year of this sent to landfill. Fresh vegetables (27%), bakery (23%), meat and fish (19%) and fresh fruit (17%) contributed the most to discarded product. The motivators for encouraging food waste reduction were: concern for the environment; making profit; caring for the community; and doing the ‘right’ thing. The barriers to food waste reduction were: training and educating staff; food safety concerns; quality standards; availability and capacity of waste diversion avenues; and lack of available resources. Audit data and food waste data recorded by retailers were similar. NZ has a number of policies and practices that successfully divert retail food waste away from landfill, in particular, retailers have established relationships with various groups that use their waste as a resource including protein reprocessors, local farmers, and food rescue charities.     

Competition in Grocery Retailing: The Impact of a New Strategic Group on BLS Price Increases

Metropolitan areas with a significant presence of warehouse stores had lower retail food price increases during 1977 to 1992 than did areas with no warehouse stores. The negative impact occurred largely during the first half of the 15-year period. Strategic learning appears to have led to a different response from incumbent supermarkets during 1985–1992. Change in prices was positively related to change in concentration and negatively related to entry.     

远程教育的研究与实现

论述了利用 Internet进行远程教育所具有的开放性、灵活性、分散性等特点 ,并对美国和中国远程教育的发展与现状进行了分析 ;以一个基于 Internet的远程考试系统——《远程考试平台系统》为实例 ,阐述了基于 Internet的远程考试系统的开发中所需要的硬件、软件、相关技术、开发环境以及远程考试系统实施的步骤 :1 )数据结构的设计与后台数据库的构建 ;2 )教师出题及试题生成 ;3 )学生答题。     

Optimal ordering policies in response to a discount offer

Sometimes supplier offers a temporary price discount to increase cash flow or decrease the inventory level of certain items. Thus, the manufacturer may be able to improve the effectiveness of his inventory system by ordering a special quantity at this sale period. In this paper, economic order quantity (EOQ) models with a discounted price are developed to obtain the optimal ordering policy during the sale period for five different cases: (a) coincidence of sale period with replenishment time, (b) non-coincidence of sale period with replenishment time, (c) sale period is longer than a cycle, (d) discounted price as a function of the special ordering quantity, and (e) incremental discount. Each case has its own characteristics of the sale period and the discounted price. The objective is to take the maximum possible advantage from the discounted price by ordering a special quantity during the sale period. The optimal ordering policy is obtained by maximizing the difference between the two costs: Regular EOQ cost and special quantity cost during the sale period. Moreover, a comparison of different discount scenarios is developed to sense the effect of different parameters on the ordering policies. The annual gain obtained is linearly related to the discount and the on-hand remnant inventory. Numerical analyses are provided to illustrate and testify the values of the optimal special quantity. The analysis showed an impressive improvement in the effectiveness of the inventory system when a special order is placed during the sale period. The optimal special quantity is driven for each case to visualize real-life problems. Sensitivity analysis is also initiated to study the change in the total savings with respect to the variation of the special optimal quantity.     

上海百货店服装零售规模研究

本文从上海百货店服装零售现状出发,在市场调研的基础上,就百货店中服装类商品的销售额、经营面积、经营服装品类、服装品牌格局四个指标进行分析,从以上四方面研究上海百货店服装零售规模发展状况,并对其特征进行总结和分析。根据本文的结论,百货店可以更加合理地调整品类布局和经营策略,服装企业可以对上海百货业中服装的格局和特点有清晰的认识,对企业未来的发展方向起到一定的参考作用。     

Food environments in Malta: Associations with store size and area-level deprivation

Food environments are potential targets for interventions to reduce obesity prevalence, particularly in island settings that are typically dependent on food imports. This observational study aimed to characterise the availability, quality and price of foods and beverages in a nationally representative sample of grocery stores in Malta using the Nutrition Environment Measures Survey for Stores (NEMS-S) instrument, and to examine the association between area-level density of different types of food stores and the likelihood of children living in these areas being overweight or obese. Fieldwork was carried out between March and May 2014. There was a strong positive correlation between store size and NEMS-S score (p = <0.001), suggesting that smaller grocery stores generally offered a smaller range of products and fewer healthy food/beverage options than larger supermarkets. Across all stores, median prices of certain ‘healthier’ versions of foods were more expensive than their less healthy alternatives. A significant association between risk of childhood overweight, and density of confectionery stores in children’s locality of residence, was found (OR 1.19; 95% CI: 1.04, 1.37). These baseline findings highlight opportunities to improve the food environment in Malta to support more healthful eating, and may be of particular interest to public health practitioners in island settings.     

校园网中Linux系统安全与管理

校园网作为学校重要的基础设施,其安全状况直接影响着学校的教学活动。Linux是一个开放式系统,可以在网络上找到许多现成的程序和工具,这既方便了用Linux系统的校园网用户,也给黑客提供了入侵的便利。介绍了Linux系统功能的一些设定方法,以及日常需要采取的一些防护措施,为提高Linux系统的安全性提供一些建议。     

Optimal production–inventory strategies for a HMMS-type reverse logistics system

The aim of the paper is to find optimal inventory policies in a reverse logistics system with special structure. It is assumed that demand is a known continuous function in a given planning horizon and return rate of used items is a given function. There is a constant delay between the using and return process. We investigate two stores. The demand is satisfied from the first store, where the manufactured and remanufactured items are stored. The returned products are collected in the second store and then remanufactured or disposed. The costs of this system consist of the quadratic holding costs for these two stores and the quadratic manufacturing, remanufacturing and disposal costs.The model is represented as an optimal control problem with two state variables (inventory status in the first and second store) and with three control variables (rate of manufacturing, remanufacturing and disposal). The objective is to minimize the sum of the quadratic deviation from described inventory levels in stores and from described manufacturing, remanufacturing and disposal rates. In this form, the model can be considered as a generalization of the well-known Holt et al. (Planning Production, Inventories, and Work Forces, Prentice-Hall, Englewood Cliffs, NJ, 1960) model with two warehouses. After solving the problem, we give some numerical examples to represent the optimal path in dependence of the demand rates.     

555IC应用的一个新思路

从555IC的基本逻辑功能和基本特性出发,论述了把555IC定时器用作门电路的理论依据和电路接线方案,分析了该门的电压传输特性、输出特性、负载能力等。该门具有一般门不可比拟的特色和突出特点:电路简单,使用灵活方便;该门电路的负载能力比普通门提高了几十倍甚至上百倍,解决了普通门阈值电压不便调节以及输出电平转换难的问题。     

Considering stochastic lead times in a manufacturing/remanufacturing system with deterministic demands and returns

In this paper we study a manufacturing/remanufacturing system with stochastic lead times and a constant demand. We base our approach on previous research in which we have developed models to describe an inventory system with stochastic lead times. In this paper, we first adopt this method to manufacturing/remanufacturing situations, where there are essentially two supply sources for replenishing serviceable inventory. We then provide a solution procedure when a cycle ordering policy is used. Secondly, we investigate the possibility to use a dual sourcing ordering policy in which each order is split between a manufacturing and a remanufacturing process. Finally, we compare the two ordering policies and illustrate how the lead-time patterns influence the economic consequences.     

The management of R & D technological progress as an object for applied systems analysis

Mankind's prospects both for finding new types of resources and for ensuring efficiency in resource utilization and substitution depend upon our success or failure in solving the problems of organizing and managing technological systems. A generalized scheme describing interaction among the basic elements of the management of national science and technology (ST) activity is outlined, and one particular element isolated for detailed examination: the system analysis and systematic assessment of new technology (SANT). The role of SANT in the context of decision-making in the management of ST progress is described, together with the methodological arsenal available. No one technique is universally good; the problem is to find systematic means of using a selection of methods which mutually compensate for each other's weaknesses. Further difficulties are encountered over the non-comparability or absence of initial data, and a framework for viewing the various classes of data available and making use of them is outlined. Examples are given of the practical application of SANT to problems such as the development of a macro-model., for the planning of national ST policy, and a model of technological change in the area of the science, technology, and exploitation of computers. A system is described which handles the data stores and information flows necessary for performing SANT routines.     

The Economics of Retailing Formats: Competition Versus Bargaining

We set up a merger game between retailing stores to study the incentives of independent stores to form a big store when some consumers have preferences for one‐stop shopping. Such one‐stop shopping creates complementarity between products, leading in turn to lower prices after a big store is formed but may also lead to an improvement in the bargaining position vis‐à‐vis producers through the creation of an inside option that small stores do not have. We find that big stores will not be formed when the stores' ex ante bargaining power vis‐à‐vis producers is high. Otherwise, an asymmetric situation occurs with only one big store created when one‐stop shoppers are abundant.     

Lotus Notes R5视图中的排序设计

视图是 Lotus Notes数据库与使用者之间的桥梁 ,设计出色的视图离不开各种排序方法 ,一般排序可以设置自动排序列或是用户排序列 ,可以有一个或多个排序列 ,但是一般排序只能实现简单的排序功能 ,同一列只能是按升序或是降序排列 ,而复杂排序利用隐藏列可以实现打破同一列中只能按升序或降序排列的限制 ,本文对各种排序的设计方法做了全面的介绍 ,并以实例给出了复杂排序的实现方法。     

考虑质押物损耗的存货质押融资决策模型

质押物的完整性是关系存货质押融资业务能否顺利开展的重要问题,质押物损耗长期困扰各参与方,阻碍了存货质押融资业务的顺利开展。考虑质押物损耗和第三方物流企业对质押物监管所带来的损耗节约的基础上,研究了存货质押融资最优决策。研究表明:当零售商的初始现金余额很低时,零售商的最优订购数量随着初始现金余额的增加而减少,之后零售商最优订货量保持不变,直到初始现金余额大于某一水平时,零售商的最优订货量开始增加;在零售商贷款且不存在破产风险时,银行的收益随着零售商初始现金余额增加而减少;当风险估值是需求的增函数时,零售商的最优订货量随利率减少。