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The purpose of this paper is to propose a novel method under the name of genetic simulated annealing algorithm (GSAA) and ant colony optimization (ACO) algorithm for assembly sequence planning (ASP) which is possessed of the competence for assisting the planner in generating a satisfied and effective assembly sequence with respect to large constraint assembly perplexity.

Based on the genetic algorithm (GA), simulated annealing, and ACO algorithm, the GSAA are put forward. A case study is presented to validate the proposed method.

This GSAA has better optimization performance and robustness. The degree of dependence on the initial assembly sequence about GSAA is decreased. The optimization assembly sequence still can be obtained even if the assembly sequences of initial population are infeasible. By combining GA and simulated annealing (SA), the efficiency of searching and the quality of solution of GSAA is improved. As for the presented ACO algorithm, the searching speed is further increased.

Traditionally, GA heavily depends on the choosing original sequence, which can result in early convergence in iterative operation, lower searching efficiency in evolutionary process, and non‐optimization of final result for global variable. Similarly, SA algorithms may generate a great deal of infeasible solutions in the evolution process by generating new sequences through exchanging position of the randomly selected two parts, which results in inefficiency of the solution‐searching process. In this paper, the proposed GSAA and ACO algorithm for ASP are possessed of the competence for assisting the planner in generating a satisfied and effective assembly sequence with respect to large constraint assembly perplexity.

The UK is a leader in the implementation of surface mount technology, and SMARTEX '91 sponsored by the SMART Group is one of only a few shows organised worldwide which is dedicated solely to this field. Perhaps it was not surprising then that this year's three‐day event proved a great success.

SOME twenty years gone by I was inspanned into a movement to explain automation to the nation which was said to be apprehensive of its effects on full employment. In vain I explained that automation was industry's response to labour shortage and that unemployment was a consequence of economic not technical policies; that it was impossible to start new industries with an only marginally increasing work force, unless it could be staffed by those deployed from industries whose productivity was rising.

TO all our readers we can wish a happy and prosperous New Year with greater confidence than usual that the coming months will translate the familiar hope into reality. The reason for that optimism is National Productivity Year. There is growing evidence that the public understands and appreciates its central theme. Naturally the official Guildhall opening attracted wide publicity. Since then it has been reinforced through the addresses given by prominent personalities at meetings up and down the country; meetings which will continue and build up a favourable climate in industry.

The electronics industry is a key industry in South Korea. To improve efficiency and maintain a competitive edge in fast-paced technological age it is critical to synchronize production supply with market demand. This paper focuses on the strategies which make the “just in time” production system within the electronic supply chain. The presented case study of Samsung Electronics Thin Film Transistor-Liquid Crystal Display (TFT-LCD) Inbound Logistics provides a solid example of process integration in the areas of: packaging, transportation and information sharing. The problems faced by Samsung Electronics in the early 2000’s were a direct result of an imbalance between increased traffic/demand and existing production capacity. The most detrimental of these problems caused delays in supply, shortage of space in the hub center and the bottlenecking of supply transportation. This paper demonstrates how Samsung Electronics reexamined and systematically streamlined their existing processes and how they successfully integrated “lean thinking” strategies to all areas of TFT-LCD production. As a result of the integration of these strategies, Samsung Electronics began using a line-to-line packing system which focused on packing items in a group using a standardized, returnable packing system. Additionally, they opted to replace their paper invoice system for an improved transportation system through which a data could reflect flows of information and materials in real time. The integration of these strategies gave Samsung Electronics a new approach to TFT-LCD Inbound Logistics which allowed them to overcome their dilemmas and resulted in successful outcomes, decreased lead times, higher quality products and an reduction in total costs.

Much of the evaluative research on groupware in organizations so far has been preoccupied with the role of groupware as a new interaction medium to replace or extend face‐to‐face communication in groups. It has focused on gains and losses from a group interaction point of view, typically disregarding the impact of other functions such as group access, and contribution to information concerning the organization. Attempts to bridge this gap with an action research into the effects of the introduction of an asynchronous groupware system to support business process improvement groups in a service company based in Brazil. The research suggests that improvements in business redesign efficiency and effectiveness can be attained not only from asynchronous groupware support to group communication, but also from public sharing of historical information about previous business process improvement efforts, and by providing a repository of information about business processes which could be candidates for improvement. Concludes with the proposal of an explanatory model, describing the relationship between the introduction of technology, its integration with a business process improvement meta‐process, and its effects on the efficiency and effectiveness of that meta‐process.

Argues that the design of the Volvo Uddevalla plant may be described as a process with an “internal logic” in which design options were eliminated through irreversible design decisions until only one alternative remained ‐ an unorthodox alternative comprising, for example, long cycle time work never used before for full‐scale production of automobiles. Contends that the most innovative features of the Uddevalla plant ‐ i.e. the detailed layout in the assembly workshops and the corresponding unorthodox production principles used ‐ were in many respects an unanticipated outcome of the design process. Pre‐existing gross layout of the plant as well as the interaction between the materials feeding techniques adopted and the operation of the automated guided vehicle system. When this was perceived by the Volvo managers, the design process had passed the point of no return, i.e. the investments made and lack of time prevented regression to more traditional layouts and production principles.

Draws upon recent legislative changes to Wales to provide new evidence and understanding of the way in which government reforms in the UK have impacted upon the promotion of equality of opportunity at government level. Analyses the problems and challenges that this new legislative duty presents for the elected representatives and bureaucrats as well as the civil groups it was designed to help. Points out a wider significance of these changes and engages the debate about the relationship between government, law and the promotion of equality.

Manufacturing errors, which will propagate along the assembly process, are inevitable and difficult to analyze for complex products, such as aircraft. To realize the goal of precise assembly for an aircraft, with revealing the nonlinear transfer mechanism of assembly error, a set of analytical methods with response to the assembly error propagation process are developed. The purpose of this study is to solve the error problems by modeling and constructing the coordination dimension chain to control the consistency of accumulated assembly errors for different assemblies.

First, with the modeling of basic error sources, mutual interaction relationship of matting error and deformation error is analyzed, and influence matrix is formed. Second, by defining coordination datum transformation process, practical establishing error of assembly coordinate system is studied, and the position of assembly features is modified with actual relocation error considering datum changing. Third, considering the progressive assembly process, error propagation for a single assembly station and multi assembly stations is precisely modeled to gain coordination error chain for different assemblies, and the final coordination error is optimized by controlling the direction and value of accumulated error range.

Based on the proposed methodology, coordination error chain, which has a direct influence on the property of stealthy and reliability for modern aircrafts, is successfully constructed for the assembly work of the jointing between leading edge flap component and wing component at different assembly stations.

Precise assembly work at different assembly stations is completed to verify methodology’s feasibility. With analyzing the main comprised error items and some optimized solutions, benefit results for the practical engineering application showing that the maximum value of the practical flush of the profiles between the two components is only 0.681 mm, the minimum value is only 0.021 mm, and the average flush of the entire wing component is 0.358 mm, which are in accordance with theoretical calculation results and can successfully fit the assembly requirement. The potential user can be the engineers for manufacturing the complex products.

This paper presents a solder joint engineering reliability model — Solder Reliability Solutions** (SRS) — and its application to surface mount area‐array and chip‐scale assemblies. The model is validated by failure data from 33 accelerated thermal cycling tests, and test vehicles covering several generations of component, assembly and circuit board technologies and a variety of test conditions. The SRS model has been implemented as a PC‐based design‐for‐reliabilltytool that enables rapid assessment of assembly reliability in the early stages of product development.