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Over the last few years, several international studies have independently shown a significant correlation between the number and intensity of manufacturing practices in use and the performance of a firm. The conclusion is an unsettling: “the more the better.” This paper uses the Global Manufacturing Research Group’s (GMRG) second round database to deepen our understanding of this relationship. The shape of a scatterplot of practices versus performance resembles the shape of an American or rugby football and is often called the “performance football”. The performance football seems to be a general phenomenon so, as practices are added, a firm should garner earlier performance improvements if it followed the upper edge of the performance envelope. This is consistent with the “sandcone” model or sequential capability building model that suggests that a firm should first invest in quality practices and then add others over this base. We first demonstrate the relationship between practices and performance holds for the GMRG data and then we make detailed comparisons of the firms along the upper and lower edges of the football. The comparisons provide some evidence that there is a sandcone effect.

Management of the natural environment is becoming an increasingly important issue to manufacturing firms, yet their managers are also challenged to implement changes that improve competitiveness. T...

Manufacturing firms have given management of the natural environment higher priority as public awareness and scrutiny has increased. To help understand management's role in this process, a basic conceptual model of environmental management within operations is developed. The model proposes that the general orientation of operations managers on environmental issues ranges from proactive to reactive, and this is intrinsically related to the investment pattern in environmental technologies. Results from an empirical validation of this model are presented for a sample of plants from the furniture industry. Three distinct groups were identified based on the linkage between environmental management orientation and investment in environmental technologies. Counter to the prescriptive environmental literature, which recommends that proactive orientation should emphasize pollution prevention (i.e., fundamental product and process changes), proactive managers implemented a balanced portfolio that also included a sizable proportion of pollution control technologies (i.e., traditional end-of-pipe controls and remediation). Contextual factors also differentiate among these three groups, thus suggesting options for senior management to assist plant managers to become more proactive and to improve environmental performance.

The Global Manufacturing Research Group (GMRG) is an informal group of researchers conducting operations management research throughout the world. Describes aspects of their survey research on manufacturing practices. Presents the background of the project, a bit about the group itself, and specifics on getting involved in the group. Presents the principles which guided the first and second rounds of the GMRG global survey and the theory underlying their survey instrument and its revision. Finally, provides several details of the research methodology and some of the research findings.

This paper presents a general analytical framework for making bilateral comparisons of manufacturing practices. The approach suggests a grouping of the data, defines a conservative test called a pure regional effect, and matches the data types to the appropriate statistical tests. The methodology is used to compare manufacturing practices in North America with those in Western Europe using data compiled by the Global Manufacturing Research Group. The broad hypothesis tested is that the two regions are more similar than different. For the two industries studied (small machine tools and nonfashion textiles), this hypothesis holds. Fewer than 10% of the 119 variables investigated have a significant pure regional effect. This suggests that the lack of success of joint ventures between North American and European firms must be attributed to factors other than differences in manufacturing practices. These variables for which significant effects were found reflect differences in external orientation, asset utilization and the management of details. Despite the overall similarities, differences in these factors could be important for American Managers contemplating partnerships with European companies.

The purpose of this research was to define and rank key barriers to the effective management of international manufacturing operations. An international panel of experts, composed of practitioners, academics and consultants, was surveyed using a Delphi process to identify the key barriers, to explain the rationale for their selection and to rank them. The highest ranked barrier was general lack of a global view by management. Among the other highly ranked barriers were contemporary managerial issues like manufacturing strategy and managing international factory networks. Some traditional technical concerns like cultural and language differences and managing global logistics were also highly ranked. The responses clustered into two groups with the largest group focusing more heavily on contemporary manufacturing concerns while the other group emphasized more traditional technical topics. The results help establish priorities for developing research agendas, orienting teaching programs and focusing company resources.

This paper reports the results of simulation experiments that compared the inventory efficiency (i.e., the customer service level provided by a given level of inventory) for two different inventory policies. One of these policies uses time-phased information on future demands like that found in material requirements planning (MRP) systems, while the other (the reorder point or ROP policy) relies on forecasts implicitly based on average past demands. After establishing that the MRP policies dominate for reasonable conditions, the uncertainty of the forecasts was manipulated until the policy preference was reversed. It requires a very perverse relationship between the forecast and actual demand before ROP beats MRP on inventory efficiency.

SUMMARY This paper presents a comparison of the manufacturing planning and control practices between firms in South Korea and Europe in the non-fashion textile and small machine tool industries. The key differences in practice were found in the details of forecasting and production planning, the market influence on shop-floor activities, the organizational level used in planning and control, and the level of sophistication in terms of computers and techniques used. The implications of these findings are important for firms with plans to enter into joint ventures or other cooperative arrangements. The data used in this study are from a large data base of actual manufacturing practices collected from countries around the world.

This paper examines the use of sampling procedures as a solution methodology for large combinatorial problems. Three sampling strategies are investigated: random sampling (each alternative is equally likely), biased sampling (alternatives' probabilities are biased by specified criteria), and improvement sampling (alternatives' probabilities are dynamically changed based upon new information). These three methodologies are illustrated and compared on the basis of solution quality and computer time requirements.

The management of inventories and determination of transportation policy are normally carried out by different groups of people in an organization. These activities interact, however, when the transportation is used to replace inventory and when the transportation alternatives have different speed, reliability, and cost characteristics. This paper presents exact and heuristic procedures for jointly determining the inventory reorder points, order quantities, and transportation alternatives that provide minimum total transportation and inventory costs. The effectiveness of each procedure is demonstrated for a broad range of problems. The heuristic procedure was also applied to actual company data to determine the potential for cost savings. The results showed that savings were possible both from improving the current procedures and from applying the procedure developed in this study.

This article presents the results of applying multicriteria ABC analysis to maintenance inventories. A large service organization and a consumer goods manufacturer participated in the study. The managers in both organizations used cost and noncost criteria for developing the ABC categories for inventory management. The study shows that managers can develop noncost criteria and classify the inventory items in ways that combine the criteria types. Specific policies were defined for managing the items in the industrial firm. Once the benefits of the methodology were demonstrated, a year-long program for implementing the system was developed. The project is estimated to cost less than 10 to 15% of the available storeroom clerk manhours and provide substantially greater benefits.

SUMMARY This paper presents results from a simulation experiment evaluating 14 different single stage lot-sizing procedures. Uncertainty in the form of forecast errors was used as one factor in the experiment. In order to prevent different service levels from confounding cost comparisons, enough safety stock to achieve a 100% service level in all situations was introduced. The ranking of the rules under uncertainty turned out to be very different from the ranking when no demand uncertainty was present. Statistical differences were found between the six best lot-sizing procedures when there was no uncertainty. When forecast errors were present, however, no differences existed for the six best rules in this situation. Thus, uncertainty not only changed the relationship between the lot-sizing rules, but also the character of this relationship.

Prioritising items for management attention has been advocated in operations management for a long time, normally using ABC analysis (inventory control). This focuses attention on the “A” category items to maximise managerial effectiveness. Empirical evidence shows that this is a reasonable rule for allocating scarce resource‐management time but presents difficulties when the manager has to take more than one important dimension of a situation into account. A joint criteria matrix is put forward within the ABC framework and an industrial application given. The joint criteria matrix has practical utility provided ranking on some scale of measurement is realistic. The appropriate number of categories must be defined by the user. Combining criteria will probably require different analytical approaches, e.g. goal programming or heuristic approaches. Utilisation of the matrix by managers can provide an explicit method for taking a range of criteria into account in the development of inventory policies.

Material requirements planning (MRP) is a way to develop the time phased material and other resource requirements to satisfy the needs of a master production schedule. Hierarchical production planning (HPP) is a framework for analysis and decision making in complex production environments. They are complementary approaches to the decision support system needs of multi-stage production systems. The hierarchical approach provides for efficient management review of proposed plans at corporate, plant, and shop levels while MRP provides a sound and detailed basis for understanding the implications of proposed plans and for executing the selected plan. The relationships between these two approaches are illustrated with an example application.

This paper presents a framework for characterizing and studying the uncertainty which can affect inventory investment and service level performance in a material requirements planning (MRP) system. It also presents the results of a simulation experiment which compared two techniques (safety stock and safety lead time) for building inventory to protect against uncertainty. The simulation results disclose consistent differences between the techniques in protecting a representative part against timing and quantity uncertainty in both demand and supply for the part. The paper not only provides some initial insights into the behavior of MRP systems under uncertainty, but also establishes some guidelines for choosing between safety stock and safety lead time.

This paper investigates the use of the coefficient of variation (CV) as a measure of requirements lumpiness (the amount of variation in requirements from period to period) in material requirements planning (MRP) research. CV is used as a factor in MRP research even though it is limited as a measure. Any sequence of requirements will have a unique CV, but any CV can represent a variety of requirements sequences. This limitation raises questions concerning the robustness of CV as a measure. In this paper, two other aspects of the requirements sequence for a given CV are investigated: the procedure used to generate the requirements and the manner in which the requirements are grouped. A simulation comparison of selected lot-sizing techniques is used to conduct the investigation. With respect to these two (new) aspects of the requirements sequence, CV appears to be a robust measure.

The article discusses the results of a study where the performance of a decision model was compared to the performance of human decision makers. A simple inventory management game was used to compa...

Most of the procedures that have been developed to find solutions to the single-machine, multi-product lot scheduling problem depend on judgment to define the desirable frequencies of production for the products. In this paper we describe an iterative procedure for directly determining near optimal frequencies of production for the products and the associated fundamental cycle time which, in many cases, can be used directly for constructing production schedules. In cases where feasible schedules cannot be constructed using the values from the iterative procedure, the procedure provides a basis for changing the production frequencies and the fundamental cycle time to obtain feasible schedules.