摘要:

In this paper, the problem of ordering a series of production runs to meet a single make-to-order demand, where the various stages in the production process have binomial yields, is addressed. The use of additional procurement of part-finished material or reworking defective material previously made to supplement yield at any stage is considered. The costs of this and manufacture, disposal of surplus or shortage are assumed to be proportional to the numbers involved. Set-up costs may or may not be incurred. The treatment follows from, and builds on, a previous single-run analytical result by developing an approximation in which the problem is decomposed into a series of single runs.

ISSN:0740-817X    

DOI:10.1080/07408179908969800

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The effectiveness of a cellular manufacturing system is sensitive to fluctuations in the demand for products and the product mix. This paper presents a new formulation of the part family/machine cell formation problem that addresses the dynamic nature of the production environment by considering a multi-period forecast of product mix and demand during the formation of part families and machine cells. The goal of the multi-period formulation is to obtain a cellular design that continues to perform well with respect to the design objectives as the part population changes with time.

ISSN:0740-817X    

DOI:10.1080/07408179908969801

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Manufacturing systems have become progressively complex and costly. Simulation is increasingly being used as an analysis and evaluation method in the design and operation of these systems. The practical use of simulation in the manufacturing environment has resulted in an increase in the number of available software tools for manufacturing simulation. This paper provides guidelines for selecting manufacturing simulation software according to the intended purpose of software use. The basic criteria to be examined in the software evaluation process are listed together with the level of their importance for particular types of users.

ISSN:0740-817X    

DOI:10.1080/07408179908969802

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

We study an end-of-aisle order picking system with inbound and outbound buffer positions. The system is referred to as a miniload system with a horse-shoe front-end configuration, and is modeled as a two-stage cyclic queueing system with limited capacity. We analyze the system by utilizing known queueing results. Closed form expressions are developed for system performance measures, including the steady-state probability and system throughput. To provide some decision criteria in the design of buffer capacity, we examine the effect of the buffer size on system throughput. We give examples to illustrate how the results developed can be applied to solving real world problems. It is also shown that under heavy retrieval system demand, the system naturally achieves its optimal operating condition in the long run and it always performs dual command cycles.

ISSN:0740-817X    

DOI:10.1080/07408179908969803

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Several numerical methods have been developed for finding the minimum zone of a cylinder. This paper presents a combinatorial method termed the Minimum Shell for cylindricity evaluation. For a given set of measured data points, the method efficiently searches for the six points that determine the minimum zone of cylindricity. This method is self-contained, without the requirement of mathematical programming software support, and is equal to or superior to other methods of evaluating cylindricity in terms of accuracy, efficiency, and simplicity. Computational results are given.

ISSN:0740-817X    

DOI:10.1080/07408179908969804

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

A study of five industrial equipment manufacturers found a number of limitations in the feedback provided to engineering designers. The error-correcting function of feedback, for example, was compromised by the poor diagnostic abilities of people in other functions, and by the superficial level of peer reviews. Delays in detecting errors also meant that designers were disinclined and had too few resources to correct them thoroughly. In terms of the learning function of feedback, post project reviews were mostly absent and delayed outcomes (like product cost) made it hard for designers to associate important design criteria with specific design decisions or practices. Designers lacked systematic knowledge of the difficulties encountered in installing, operating and maintaining their products. And there were repeated errors where design organizations had failed to embody past experience in new products. The motivational function of feedback was vitiated by the absence of objective outcome measurements and little systematic guidance to designers on effective behaviours. Designers also believed there was a strong bias towards negative (that is critical and unfavourable) feedback in their day-to-day work. Several of these problems have more general explanations: (1) a general under-estimation of the extent to which knowledge of results contributes to job satisfaction among designers; (2) a similar under-estimation of the extent to which designers are uncertain about the consequences of their decisions and their general performance; and (3) a strong current-task orientation which discourages both individual and collective investment in acquiring knowledge for future application.

ISSN:0740-817X    

DOI:10.1080/07408179908969805

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Modern manufacturing systems rely on a smooth and quick transformation of the design specification into manufacturing instructions. The shift towards feature-based design and manufacturing supports this effort. One of the weak links in this chain of activities is the conversion of the design features into the manufacturing features. This article presents a method based on graph grammar parsing that converts design geometrical features into manufacturing geometrical features. These features can then be used in process planning activities. The method presented extends the state of the art of syntactic graph-based features recognition by supporting embedding transformations, attribute transfer algorithms, decomposition of overlapping features and removal of empty volumes. In addition, the analysis provided by the graph parsing algorithms implicitly treats the features as solid models without the need to perform complicated geometrical'analysis. The system was implemented for prismatic components such that they can be produced on a triple axis vertical milling machine, and currently contains 20 rules.

ISSN:0740-817X    

DOI:10.1080/07408179908969806

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The accuracy and precision of a manufactured dimension is largely dependent on the accuracy and precision of the technological processes selected for its execution. It is not unusual to have available several competing technological processes for execution of each manufacturing operation specified in a process plan, where it is generally assumed that as the precision of the technological process improves, the associated cost and yield of the operation increase. This paper presents an implicit enumeration approach to the selection of an optimum subset of technological processes required to execute a process plan under a. sequential (or adaptive) tolerance control strategy.

ISSN:0740-817X    

DOI:10.1080/07408179908969807

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The selection of multi-functional teams is a key issue in problem solving. Currently there are no papers in the literature that discuss analytical approaches to forming teams. Furthermore, no comprehensive model exists to prioritize team membership based on customer requirements or product characteristics. To deal with the underlying complexities of the team selection process, a methodology for team formation is developed. The methodology is based on the Analytical Hierarchy Process (AHP) approach and the Quality Function Deployment (QFD) method. A QFD planning matrix is used to organize the factors considered in the team selection. The importance measure for each team member is determined with the AHP approach. A mathematical programming model is developed to determine the composition of a team. The methodology developed in this paper is tested by the selection of teams in concurrent engineering. A detailed discussion of the model implementation and hov/ to reduce the number of comparisons in the AHP process is presented. Possible modifications of the model to include “soft factors”, i.e., leadership, morale, personalities of group members, group values and so on are also discussed.

ISSN:0740-817X    

DOI:10.1080/07408179908969808

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor