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The purpose of this paper is to discover whether on‐site materials handling should be performed in‐house or out‐sourced. This is done by studying visible and hidden costs related to materials handling and of the managers' awareness of these costs.

The data have been gathered through 15 interviews, a number of short discussions on construction sites, and direct observations on six occasions in four housing projects in Scandinavia.

Indirect and waste costs for materials handling on construction sites are unknown and are often underestimated during budgeting, planning, scheduling and organizing construction projects.

The short case‐studies indicate that the benefits of out‐sourcing on‐site materials handling outweigh the costs.

The solution for materials handling in practice studied in the paper is undergoing rapid development in Scandinavia.

A key task in the material handling system design process is the selection and configuration of equipment for material transport and storage in a facility. Material handling equipment selection is a complex, tedious task. However, there are few tools other than checklists to assist engineers in the selection of appropriate, cost‐effective material handling equipment. This paper describes the development of an intelligent material handling equipment selection system called MHESA (Material Handling Equipment Selection Advisor). The MHESA is composed of three modules: a database to store equipment types with their specifications; a knowledge‐based expert system for assisting material handling equipment selection; and an analytic hierarchy process (AHP) model to choose the most favorable equipment type. The concept proposed in this paper can automate the design of material handling equipment selection system, and provides artificial intelligence in the decision‐making process.

This paper aims to discuss some relevant issues in the design and operation of material handling and storage systems (MH&SS) characterized by complex material flows and high‐traffic intensity. The paper seeks to provide solution examples and an analysis methodology to face large increases of materials flows through a redesign of the material handling and storage system.

At first, possible strategies to improve system performances when facing strong increments of material flows are presented and discussed. A significant case study is then analyzed in order to present a practical application of the proposed methodology. Resorting to discrete‐events simulation, the alternatives are verified, correct design choices are identified, and the resources are properly sized to develop a streamlined layout.

The paper recognises that design and upgrade of intensive material handling systems is a complex task asking for a careful study of alternatives and detailed system analysis, otherwise capacity problems and bottleneck phenomena may not be effectively solved.

This work focuses on a specific case study. The paper, therefore, will be of interest mainly to managers and designers of similar plants and large – intensive material handling systems.

The paper shows how the correct planning and analysis of design alternatives integrated with a detailed system simulation enable a drastic reduction of bottleneck phenomena, thus meeting the required capacity improvement goals when upgrading and redesigning complex and high‐volume material handling systems.

The paper, while providing insights to practitioners engaged in design and management of complex MH&SS, outlines a methodological approach which can be useful when facing major capacity improvement projects.

Retreat of the Critics. The publication, last month, of a series of six main articles on Work Study with an introductory leader in The Financial Times was yet further proof of the increasing interest and importance accorded by the nation at large to this decisive “tool of management” which has been, until comparatively recent years, the dream of a few, forward‐looking pioneers. During the past year or two, however, increasing references have been made to Work Study on the radio and television, and in the daily press. As The Financial Times points out: “The critical voices seem now to be growing fainter. For example, no less than 800 industrialists from every part of the country attended the recent conference on Work Study at Harrogate, organised by the British Institute of Management.”

In the garment industry, web lace fabric material must be tensioned and placed at the right position and orientation prior to the cutting process. In order to avoid a bottleneck, the speed of material handling must be relatively fast compared to the laser cutting speed so that the use of a laser for rapid prototyping of two‐dimensional (2D) cutting shapes is feasible. The purpose of this paper is to describe the development of a novel gripping system for handling flexible web materials.

The manner in which this intelligent material handling system operates will be discussed in this paper. This includes its system configuration, errors that may occur during the web handling operation, and sequential operations of web distortion control. The material handling system uses a machine vision system coupled with a self‐tuning motion control strategy to assist the material handling system in controlling the web tension, adjusting the web deformation parameters and transporting the web materials.

The online image analysis and a novel mechanical design concept, coupled with the motion controller, are the key issues in the mechatronic integration of this intelligent web‐based material handling system.

The paper presents a novel approach to designing and realizing an intelligent gripping system, which has not previously been attempted.

In a kitting supply system, the occurrence of material-handling errors is unavoidable and will cause serious production losses to an assembly line. To minimize production losses, this paper aims to present a dynamic scheduling problem of automotive assembly line considering material-handling mistakes by integrating abnormal disturbance into the material distribution problem of mixed-model assembly lines (MMALs).

A multi-phase dynamic scheduling (MPDS) algorithm is proposed based on the characteristics and properties of the dynamic scheduling problem. In the first phase, the static material distribution scheduling problem is decomposed into three optimization sub-problems, and the dynamic programming algorithm is used to jointly optimize the sub-problems to obtain the optimal initial scheduling plan. In the second phase, a two-stage rescheduling algorithm incorporating removing rules and adding rules was designed according to the status update mechanism of material demand and multi-load AGVs.

Through comparative experiments with the periodic distribution strategy (PD) and the direct insertion method (DI), the superiority of the proposed dynamic scheduling strategy and algorithm is verified.

To the best of the authors’ knowledge, this study is the first to consider the impact of material-handling errors on the material distribution scheduling problem when using a kitting strategy. By designing an MPDS algorithm, this paper aims to maximize the absorption of the disturbance caused by material-handling errors and reduce the production losses of the assembly line as well as the total cost of the material transportation.

A non‐contact end‐effector was applied to lift three different materials which have different physical properties. These materials are mica (as rigid material), carton (as semi‐rigid material) and non‐rigid material (woven fabric). This end‐effector operates on the principle of generating a high‐speed air flow between nozzles and the specimen surface thereby creating a vacuum which levitates the materials with no mechanical contact. In this paper, the handling results of these materials are compared with each other. The changes in the physical behavior of lifting materials were observed during the experimental work. The effect of the various air flow rates on the non‐contact handling clearance gap between the nozzle and the materials were also investigated. As a result, it was observed that the non‐contact end‐effector could be applied to handle different flat materials.

Results of an international investigation concerning the selection of materials handling methods for high rise in‐situ concrete buildings by contractors’ planning engineers in France, Germany and the UK are presented. Findings indicate that materials handling methods differ in each international location. Tower cranes still dominate for high rise in‐situ concrete buildings, although contractors will also frequently utilise concrete pumps in conjunction. Company size has little impact on the materials handling method selected. Eight predominant (construction method) selection factors are identified, and ranked for each international group of contractors. Statistically, the rankings are shown to be almost the same for each country. Relative costs, speed of construction, and site safety are the principal selection criteria. Correlation analysis reveals a degree of association between the selection factors.

THE Fourth European Work Study Congress, held in Paris during the third week of May, was a well‐organized affair. A tribute is due to M. Loubert and his colleagues for the way in which they devised such well‐lubricated machinery for the convenience of their guests and for the imaginative touch of holding the official dinner aboard a bateau‐mouche as it sailed for two hours up and down the Seine.

STIMULATING the interest of the employee in his job has become one of the most challenging problems facing management today. Daily repetition of tasks seemingly unrelated to the end product can very quickly cause boredom and fatigue, reducing individual efficiency and lowering productivity.