摘要:

In this paper the implementation approach, adopted by an engineering company, of an innovative team management system known as the ‘green area’ concept is researched and analysed. The system was introduced to improve contract time and cost control and change the business culture to one of high personnel involvement and responsibility. The determinants for successful business implementation of this system are evaluated using a multi-attribute framework. These determinants have been specified as a net of organizational change parameters for the successful implementation of business improvement strategies.

ISSN:0020-7543    

DOI:10.1080/00207549608905073

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

A model for the measurements from a multiple stream process is analysed as a special case of a multivariate control chart by principal components analysis. The principal components meet the objective of partitioning the control problem into statistics that are sensitive to two types of assignable causes. Simple test statistics result and performance analyses are provided.

ISSN:0020-7543    

DOI:10.1080/00207549608905074

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Petri nets (PNs) have recently emerged as a promising approach for modelling flexible and automated manufacturing systems. PNs are a graphical and mathematical modelling technique that is useful for modelling concurrent, asynchronous, distributed, parallel, nondeterministic, and stochastic systems, as attested by a steady stream of papers which appeared throughout the 1980s. Since 1989, there has been an explosion of interest in using PNs to model, simulate, and analyse manufacturing systems. We present an overview of PN theory. We then present a schema for categorizing PN models of manufacturing systems, followed by a survey of PN models of flow lines, automatic transfer lines, job shops, flexible manufacturing systems, and assembly systems. This discussion represents the most comprehensive survey of applications of PNs to manufacturing through 1994. Finally, we present a summary and some conclusions.

ISSN:0020-7543    

DOI:10.1080/00207549608905075

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

This paper deals with the problem of production scheduling in a two-stage hybrid flow shop, which consists of one machine in the first stage, and multiple process lines in the second stage. In the first stage, materials are batch-processed, which are then fed into one of several process lines in the second stage, depending on the final product specifications. First, we formulated the total flow time or makespan, the capacity utilization and the maximum work-in-process level as measures of manufacturing performance. We analysed, through a series of numerical experiments, how these performance measures are affected by lot sizing, sequencing rules and the scheduling scenario. The following points were clarified. (1) The ratio rule yields the best performance with regard to the makespan, but the LPT rule yields the best performance with regard to the maximum work-in-process level, (2) The optimum lot size is also affected by such operation conditions as the unit processing time, the setup time, and the ratio of unit processing times in the two stages. (3) The starting point for making a schedule should be set in the bottleneck stage with regard to the makespan.

ISSN:0020-7543    

DOI:10.1080/00207549608905076

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Environmental awareness and legislation are pushing manufacturers to introduce new ‘green’ products that, during their whole life cycle, have a low impact on the state of natural resources. Unfortunately, it is not completely clear how accounting information, physical measures and qualitative information, expressing the effects of each product development initiative, can be structured to support decision making. The paper is aimed at designing an integrated approach that takes both tangible and intangible effects into consideration and starting from the available information, suggests different decisional tools according to the decision maker's objective. In particular, at an earlier stage the paper defines an operating framework for the identification of significant evaluation criteria to support decision making on programmes aimed at introducing new ‘green’ products. At a later stage, the paper analyses whether different managers' environment related priorities require distinct types of data to be included in the selection procedure and hence suggest the most effective evaluation technique within different decisional contexts.

ISSN:0020-7543    

DOI:10.1080/00207549608905077

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Current methods for assuring assembly accuracy are mainly based on process capabilities and specification limits of each mating part without considering the interrelationship between the distribution of fit size and those of mating sizes (typically, hole and shaft). If a high assembly accuracy is required, the control of machining processes of mating parts will be very strict and the manufacturing cost will be greatly increased. Aiming at assuring precision assembly accuracy with an acceptable manufacturing cost, a new approach based on fit capability indices for process parameter design and quality improvement is described in this paper. Referring to process capability indicesCpandCpk, fit capability indicesFCpandFCpkare proposed to provide a new measure for estimating the fit property and assembly quality. Typical applications are introduced with detailed case studies.

ISSN:0020-7543    

DOI:10.1080/00207549608905078

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

This paper considers a production environment in which multiple products produced in a batch process share several facilities, and the products must be grouped (or, equivalently, assigned to facilities) so as to minimize associated inventory carrying costs (an NP-hard problem). The main contributions of the paper are (1) to derive a polynomial-time procedure that computes optimal solutions to an important special case of the problem, (2) to extend the procedure as an heuristic to the more general case, and (3) to demonstrate computationally that the heuristic is remarkably effective in the general case.

ISSN:0020-7543    

DOI:10.1080/00207549608905079

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Toyota's goal-chasing method has proved effective for dealing with practical-sized sequencing problems for mixed-model assembly lines in just-in-time (JIT) production systems. Miltenburg introduced the multi-level concept to JIT assembly line sequencing, and his remark about Toyota's neglect of product ‘usage’ smoothing (PUS) when determining the assembly-line product sequence, primarily gave impetus to this study. We note that for most JIT systems, PUS would only be of practical significance, if it helps to achieve sub-assemblies and parts usage smoothing (SUS). In this paper, we conduct a simulation experiment for two-level sequence scheduling for JIT assembly lines. Using the SUS objective value as the metric, the results show that in a comparatively higher percentage of cases (relative to single-level SUS objective scheduling), which can be reasonably considered as statistically significant, better sequences are produced, This phenomenon is found to apply to Toyota's SUS objective as well as Miltenburg's.

ISSN:0020-7543    

DOI:10.1080/00207549608905080

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Evaluation measures of mixed-model assembly lines are examined. The squared deviation from linear component usage and related measures are often cited due to their apparent consistency with the goals of a just-in-time fabrication shop. This paper develops a different statistic which more directly measures deviations from linear component usage. It is shown that, for the environment studied, sequencing methods developed to achieve linear component usage, are not always better than purely random sequencing when the actual time of component use is measured. Next the sequencing procedures are compared, based on their ability to achieve desired production targets. It is shown that the sequencing method which smooths assembly times on the simulated assembly line, as well as methods which perform well based on the traditional measure of linear component use, achieve the highest levels of production. It is concluded that, in the environment studied, direct measures of system productivity are more useful than measures of linear component usage.

ISSN:0020-7543    

DOI:10.1080/00207549608905081

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

The formation of realistic implementable medium-range production plans requires explicit recognition of the multiple conflicting objectives of production planning. However, suggested applications of multiobjective optimization to production planning have been limited to goal programming procedures which fail to capitalize on the intrinsic flexibility of a multiobjective model. Alternatively, interactive multiobjective solution techniques could be used to allow planners to enhance decision making without excessive computational effort. This study describes an interactive multiple objective decision framework and evaluates its effectiveness via a multiobjective capacitated lot sizing model based on a real manufacturing facility. The results suggest that this approach is an effective solution strategy and useful decision aid for complex production planning problems.

ISSN:0020-7543    

DOI:10.1080/00207549608905082

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor