John Mapes

The Impact of Supply Chain Integration on Operating Performance

Reports the results of a survey of manufacturing managers to assess their perception of the changing manufacturing task and the role of the manufacturing manager. Within this context investigates the contribution of new manufacturing techniques and approaches, the involvement of manufacturing staff in service factory roles and the steps to increase integration across the value chain on manufacturing performance.

Performance trade‐offs in manufacturing plants

A sample of 782 manufacturing plants drawn from the UK Best Factor Awards database was used to investigate the nature of trade‐offs between different measures of manufacturing performance. Each plant was ranked within its industry on each performance measure, a high ranking indicating good performance on that measure and a low ranking indicating poor performance. By comparing the ranking of each plant within its industry on each performance measure it was possible to determine the extent to which good performance on one measure was correlated with good performance on other measures. Rankings on added value per employee £, quality consistency, delivery reliability, speed of delivery and the rate of new product introduction were positively correlated, suggesting that good performance on each of these factors is associated with good performance on the rest. Only the extent to which a plant exhibited product variety showed conventional trade‐off characteristics, being negatively correlated with rankings on added value per employee £ and the rate of new product introduction. This implies that, provided that individual operating units can be organized so that each is focused on a relatively narrow product range, trade‐offs can be avoided.

Process variability and its effect on plant performance

This report presents the preliminary findings of a research study to determine the factors which enable a manufacturing plant to simultaneously achieve high labour productivity, fast, reliable delivery and high quality consistency. The conclusions are based on analysis of a database containing details of 953 manufacturing plants in the UK. Based on the performance measures mentioned above, a composite performance measure was calculated for each plant in the database. The plants were then divided into groups of high performers, medium performers and low performers. Using statistical analysis, those differences between the high and low‐performing plants that were significant were identified. The main factors differentiating high‐performing plants from the rest were those associated with low process variability, high schedule stability and more reliable deliveries by suppliers.

A hierarchical model of business competence

Уточняется концепция деловой компетенции, которая широко используется, но не очень четко определена. Предлагаемая иерархическая модель объединяет различные типы компетенции, появившиеся в практике и литературе по менеджменту в последние годы. Более того, вводятся два новых типа компетенции. В работе использованы базы данных Cranfield Best Factory.

MRP with high uncertain yield losses

Abstract Certain manufacturing systems, notably those in high technology precision casting and integrated circuit production suffer from process yield losses which are both significant in quantity terms and are also highly unpredictable. This poses special problems for the provisioning of materials to support a manufacturing program and for the detailed scheduling necessary to update the priorities of work in process batches as losses occur. This paper establishes a framework of analysis to handle this problem in MRP logic. It describes the mechanisms available and discusses their relevance to the market environments in which the company is operating. The key conclusion of this paper is that different solutions are required for different market circumstances. The four key strategies developed are: 1. A: For continuous schedules, make-for-stock: Use mean yield rate and fixed buffer stocks. 2. B: For continuous schedules, make-to-order: Use mean yield rate, fixed buffers and a yield to finish monitoring system. 3. C1: For single batch production make-to-order: As for B but using a desired service level yield rate. 4. C2: For multiple batch production, make-to-order: As B but using a variable yield rate by batch. The implementation of each of these is described in relation to the business objectives of cost effectiveness and customer satisfaction.

Delivery and trade-offs

Abstract The idea of trade-offs has been one of the accepted constraints of manufacturing strategy development. However, recently the idea of the existence of trade-offs has been called into question. In particular, the World Class Manufacturing School has stated that they do not exist in the manufacturing environment. An important feature of the conventional wisdom of manufacturing has been that if a plants management wishes to achieve good delivery performance on those items that they supply on a quoted delivery date they need to quote a long lead time. The long lead times give them the ability to plan production effectively and so achieve high levels of delivery performance. The purpose of this paper was to investigate if the conventional trade-off between lead times and delivery performance still exists. The results of our research into the trade-off between lead times and delivery performance indicate that the conventional wisdom no longer applies. Our results indicate the reverse situation being present, namely manufacturing plants quoting short customer lead times were, in fact, achieving much better delivery performance than those plants that quoted long lead times.

The Effect of Capacity Limitations on Safety Stock

When a production system is operating at close to capacity then, after a period of high demand, it may take some time to restore stocks to the level necessary to provide a given level of stockout risk. During this period the risk of a stockout will be higher than intended. Uses simulation to show how customer service levels fall dramatically as average production levels approach available capacity and to determine the increases in levels of safety stock necessary to maintain desired customer service levels when capacity is limited.

Supply Networks and the Changing Role of Operations Managers

This paper reports on the first stage of an investigation into the progress which organisations are making towards fully integrated supply chains and the effect that this is having on the roleof the operations manager. Five companies were identified who are currently trying to improve the management of their supply chain. Senior managers in each company were interviewed in order to establish the degree of integration of their supply chains and the way in which the supply chain was managed.