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The purpose of this paper is to develop a quantitative model to assess probability of errors and errors correction costs in parts feeding systems for assembly lines.

Event trees are adopted to model errors in the picking-handling-delivery-utilization of materials containers from the warehouse to assembly stations. Error probabilities and quality costs functions are developed to compare alternative feeding policies including kitting, line stocking and just-in-time delivery. A numerical case study is included.

This paper confirms with quantitative evidence the economic relevance of logistic errors (LEs) in parts feeding processes, a problem neglected in the existing literature. It also points out the most frequent or relevant error types and identifies specific corrective measures.

While the model is general purpose, conclusions are specific to each applicative case and are not generalizable, and some modifications may be required to adapt it to specific industrial cases. When no experimental data are available, human error analysis should be used to estimate event probabilities based on underlying modes and causes of human error.

Production managers are given a quantitative decision tool to assess errors probability and errors correction costs in assembly lines parts feeding systems. This allows better comparing of alternative parts feeding policies and identifying corrective measures.

This is the first paper to develop quantitative models for estimating LEs and related quality cost, allowing a comparison between alternative parts feeding policies.

The principal results of a study concerning the industrial transfer in MOS memory wafer fabrication, of an intrabay material handling system based on a track‐robot are presented. A prototype system, installed in L'Aquila University Operations Laboratory, was used in order to verify the congruence of the track‐robot performance within the productive tasks to be carried out. Particular attention was given to the safety systems and the vibrational behaviour of the track‐robot, that strictly influence the aspects that can create risks for a person's safety or the wafer's integrity.

Looks at studies into the definition of design and management criteria for assembly cells with co‐operating robots. Examines task typologies into which the assembly process can be divided and discusses co‐ordination levels and control‐communication architectures. Also looks at the various phases of application development and how it covers many of the same areas of the manual assembly process. Concludes with a consideration of the three main classes of constraints between the actions which different robots have to carry out and states the co‐ordination level that robots have to maintain during constraint‐affected operations depends on these classes.

Reports on a comparison by computer simulation between conventional periodic loading (PL) and job‐group loading (JGL). When conventional PL is used, the search of the best part input sequence must be performed in order to optimize performance of a flexible manufacturing system (FMS). JGL works, instead, as a dynamic rule for real time scheduling of FMS, defining a part releasing policy able to guarantee the reaching of a periodic steady state without non‐productive times on the bottleneck workstation. However, JGL does not assure, in some cases, the same performance arising from the optimal part input sequence of conventional PL, in terms of non‐productive times in FMS filling and emptying phases, work in progress and throughput time. The paper demonstrates that using any JGL rule or the best PL part input sequence gives rise to negligible differences in FMS performance. Furthermore, the dynamic capabilities of the JGL also allow for spontaneously restoring the FMS periodic steady state without non‐productive times after any transient, for instance when production mix changes occur.

The paper presents results of a pilot programme aimed at efficiency improvement in a multi‐site factories system for automotive component production. Firstly, the company background has been outlined and main problems of the old manufacturing system have been examined. In order to increase competitiveness in global and turbulent markets a renewed organization approach has been proposed based on total manufacturing management and just‐in‐time methodologies. Improvements in set‐up and lead times, work in progress, material handling, product and process quality, environmental effects, have all been assessed, keeping a quite low project cost (around $4 million).

The problem of environmental management in a protected area has been examined in the paper. A methodological approach based on geographical information system (GIS) technology has been proposed in order to aid in all planning phases. The software tool has been illustrated and a case study has been presented with reference to a national park. Results show capabilities of the developed decision‐support system in identifying and comparing technical‐economical solutions compatible with protected area constraints.

Presents the results of a pilot project on implementation of just‐in‐time (JIT) production for an automotive component (sleeve for synchronizing groups). Describes the old manufacturing system and outlines the related problems. Proposes, with the aim of reducing set‐up times and increasing flexibility, quality and logistic performances, a new advanced manufacturing system using JIT as an approach. Presents a summary of costs and benefits arising from the new system, outlining factors such as a total cost of $3 million and a lead time reduction of 60 days.

The paper presents results of a pilot project on technological innovation of main flexible components for automotive suspension systems, that are coil springs and stabilizer bars. Current technology has been described and related problems have been outlined. In order to fulfil features such as compactness, lightness and environmentally conscious design, solutions based on new forms, materials and manufacturing processes have been proposed. Improvements in weights, dimensions, noiselessness, corrosion and fatigue strength, environmental effects, have been all assessed, keeping a quite low project cost (around $3 million).

FMS real time scheduling requires the concurrent solution of both loading and despatching problems. The loading strategy is the most critical and important scheduling decision in an FMS. Presents an effective loading rule (job‐group loading rule), based on experimental observations: a group of jobs, reflecting the ratios of the production mix, is loaded on the input warehouse every time that it is completely empty; all the jobs loaded on the input warehouse have to be accessible for the material handling system. Demonstrates how this job‐group loading works as a dynamic rule for real time scheduling of manufacturing systems, defining a part releasing policy able to guarantee reaching a periodic, steady state production. The capability of the job‐group loading rule has been verified when the FMS characteristics are closest to a real situation. Analyses the effects of the interferences on transport operations, the variability of machining times, the finite capacity of interoperational storage and the stops for preventive maintenance or breakdown. Research results show the capability in FMS management of real time scheduling based on the job‐group loading rule.

The purpose of the present paper is to provide a comprehensive framework for analyzing relationships among economic actors interconnected through internet and constituting e‐supply networks (e‐SNs).

At first the main factors characterizing e‐SN pattern are identified (organizational structures, managerial criteria and critical activities), then two separate procedures are adopted for developing an integrated reference framework. The first based on the analysis of correlations among variables influencing the factors under investigation; the second based on the analysis of different types of physical and immaterial flows among actors involved in the e‐SN. On the basis of such evidence an integrated global framework is proposed, which is then used to classify and describe some relevant literature‐based case studies.

On the basis of two newly introduced variables, namely the internal integration degree and the decision‐making concentration degree, the framework identifies four sets of organizational structures, managerial criteria and critical activities, each one coherent with specific environmental contexts.

The framework is restricted to describing and classifying different typologies of e‐SN.

The framework may be useful for assessing if the typology of organizational structure, managerial criteria and critical activities adopted for the management of a specific e‐SN, is coherent with e‐SN business environment. It may also provide useful guidelines for managers and practitioners involved in e‐SN design.

The paper provides an original integrated framework to classify e‐SNs.