摘要:

There has been much written on why and how firms become involved in entering international markets. There is less material on the production/operations actions taken by such firms. This paper investigates the differences in competitive capabilities and manufacturing performance improvement plans between globally-oriented and domestically-oriented firms. It uses data collected from 140 New Zealand manufacturing companies. The results indicate that both groups emphasize the same competitive capabilities, but the globally-oriented group is placing more emphasis on some action plans involving quality assurance, improving existing processes and design for manufacture. Their most favoured action plans are similar to those of firms in most advanced manufacturing countries which participate in the Manufacturing Futures Project.

ISSN:0020-7543    

DOI:10.1080/00207549608905052

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

One of the weaknesses of the P-median formulation of the cell configuration problem in group technology (GT) is that the number of cells required has to be specified in advance. Therefore, the most natural clustering of the input matrix might not be obtained. This paper suggests an approach for overcoming this weakness by using a new measure of similarity coefficient. Unlike most of the existing measures of similarity coefficient, the proposed measure can take both positive and negative values and therefore identifies both similarity and dissimilarity between machines. The proposed approach was tested on several problems taken from the literature. The results of this computational study demonstrate the superiority of the proposed method.

ISSN:0020-7543    

DOI:10.1080/00207549608905053

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Since it is a complex task to formalize the feature recognition problem explicitly, a large variety of systems has been developed. One of the problems these systems have to overcome is the recognition and interpretation of interacting features. A fair success has been achieved in surface based methods to recognize certain classes of interacting features. However the problem remains for general cases of interacting features. Recently much effort has been focused on the volumetric approach. We present here the current state of a volumetric feature recognition method. The system considers interacting features in prismoidal parts and it operates in two stages: (1) recognition of regions of interest: a spatial decomposition of the space bounded by a predefined circumscribing volume is performed. A ‘cell evaluated and directed adjacency graph’ is then established. This graph is traversed to identify cavity volumes. (2) interpretation: cavity volumes made up of more than one cell can be produced by different machining operations. A graph-based decomposition method and Hamiltonian path search are combined to generate interpretations which correspond to optimal machining. The system CEDAG developed in this work uses a cell-face directed graph and contrasts the face-edge and edge-vertex graphs encountered in most conventional graph-based recognition methods.

ISSN:0020-7543    

DOI:10.1080/00207549608905054

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

In this paper we examine the adjacency-based, distance-based, and weighted-criteria facility layout objective functions in an attempt to relate them to actual layout costs, which are typically dependent on material handling costs. As a result of this examination, we develop an objective function based on a basic material handling cost structure. We then show that this objective function is a generalization of the traditional weighted objective. Since specifying weights may not be an exact process, we explore the impact of imperfect weighting-value information on solution quality. In the process, we illustrate with test problems from the literature that robust solutions—good solutions as measured by more than one set of weights—can be found with a simple procedure we call therobust layoutmethod. This leads us to our general conclusion that using imperfect weighting-value information while we generate the layouts is better than using complete weighting-value information only after we generate the layouts.

ISSN:0020-7543    

DOI:10.1080/00207549608905055

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

In this paper, we study the basic behaviour of jig flow in a closed-loop automatic transfer production system which is installed to mass-produce high quality adhesive products. In this system, machine troubles occur and they cause a stagnation of jig flow. As a result, a drop of jig temperature occurs and decreases the system production rate. First, we develop a model of jig flow considering the temperature of jigs circulating in the system, and using a simulation method, we investigate the effect of the number of input jigs and a method to install buffer storages. Next, we investigate the effect of adding a supplementary heating line to the system in order to minimise a decrease of production rate caused by jigs suffering a remarkable drop of temperature.

ISSN:0020-7543    

DOI:10.1080/00207549608905056

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Over the last few years considerable attention has been focused on the form fitting algorithms used in coordinate measuring machine (CMM) software. As a result many new algorithms have been developed. However, their accuracy and applicability have been a subject of discussion and argument. This paper describes a research project aimed at a selection process for the most suitable algorithm for evaluating a given form error, and to improve the accuracy of the result using an error compensation technique.

ISSN:0020-7543    

DOI:10.1080/00207549608905057

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Group technology requires the block-diagonalisation of the machine-component incidence matrix as an essential first step towards implementation. The goodness of such block diagonal forms is usually evaluated by two measures known as grouping efficiency and grouping efficacy. The drawbacks of grouping efficiency have been exposed already in earlier studies. This study critically examines grouping efficacy and identifies its limitations. A new measure,grouping index, which overcomes the limitations of the earlier measures, is developed in this paper. The desirable properties of the existing measures have been retained. The properties of the proposed measure are analysed and compared with those of grouping efficacy for well-structured and ill-structured data sets.

ISSN:0020-7543    

DOI:10.1080/00207549608905058

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

In today's job shop, computers make information readily available, but there is limited research about which information to use and how to use it controlling a dual resource constrained (DRC) job shop. We develop and test new order review/ release (ORR) job dispatching and labour assignment rules that use different types of information. We compare the performance of a naive ORR rule (i.e., releasing all jobs immediately upon receipt) and other rules in the literature which use little information to a new ORR rule, modified load conversion (MLC), which uses all the available information. Our tests demonstrate that MLC performs better than the other ORR rules we tested. But the new job dispatching and labour assignment rules developed to use different types of information do not significantly improve performance. A sensitivity analysis demonstrates that although the shop performance is sensitive to the cost structure for every policy tested, the new MLC ORR rule performs well over a wide range of cost structures.

ISSN:0020-7543    

DOI:10.1080/00207549608905059

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

In this paper, an optimization algorithm based on the simulated annealing (SA) algorithm and the Hooke-Jeeves pattern search (PS) is developed for optimization of multi-pass turning operations. The cutting process is divided into multi-pass rough machining and finish machining. Machining parameters are determined to optimize the cutting conditions in the sense of the minimum unit production cost under a set of practical machining constraints. Experimental results indicate that the proposed nonlinear constrained optimization algorithm, named SA/PS, is effective for solving complex machining optimization problems. The SA/PS algorithm can be integrated into a CAPP system for generating optimal machining parameters.

ISSN:0020-7543    

DOI:10.1080/00207549608905060

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

This paper addresses the flow path design issue of automated material handling systems. We concentrate on the design of unidirectional guide path for automated guided vehicle systems. We present a modelling approach to determine the optimal flow path, which takes into account the impact of empty and loaded vehicle flows on the objective function to be minimized. We suggest a branch and bound algorithm, based on a depth-first search, which gives the excellent results in a very reduced time. The presented modelling approach exploits the structure of the problem to reduce the number of constraints by contraction and subtraction. Computational performance of this algorithm is compared with a procedure developed by Kaspi and Tanchoco and Kim and Tanchoco.

ISSN:0020-7543    

DOI:10.1080/00207549608905061

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor