摘要:

Tests of product quality that depend exclusively on one or more of the five senses of a human inspector are known as sensory tests. Since the ability to make correct sensory judgments can vary substantially from person to person, it is important in the selection and training of inspectors to be able to distinguish between inspectors of differing sensory abilities. This paper proposes a new approach based on the Kullback-Leibler data for classifying inspectors by panel tests. A method of deciding the same size in the test inspection lot with given risks is also suggested. The recommended procedure is simple, practical and relatively effective.

ISSN:0020-7543    

DOI:10.1080/00207548808947946

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Competitive pressures continually force management to examine cost and quality levels of production systems. In this paper these issues are addressed via a model that synthesizes several potential features of production systems: production processes, quality control procedures, in-process inventory and reprocessing. For any specified inspection configuration the model can be used, for serial production systems, to obtain closed-form expressions for two important decision variables: optimal lot size and reprocessing batch size, which minimize the total system costs. A numerical example highlights the interdependencies and the role of various system features in determining the values of the decision variables and hence in reducing the total costs. The paper also discusses the managerial implications of the model.

ISSN:0020-7543    

DOI:10.1080/00207548808947947

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

An experimental investigation has been carried out into the drilling of glass fibre reinforced plastics using HSS twist drills. A test series was conducted using a wide range of cutting conditions and drill geometry, namely cutting speed, feed rate, point angle and helix angle. Decisions relating to the ‘optimum’ drilling conditions were based on the geometrical accuracy and appearance of the produced holes. Drill wear was measured during the test trials and used as a further constraint in ‘optimum’ cutting conditions selection. Speed, feed rate and drill point angle were found statistically to be the most significant parameters influencing hole quality. Drill wear can be successfully correlated to the level of the thrust force. A simple nomogram is included to predict drill wear level from the thrust level or the amount of material removed.

ISSN:0020-7543    

DOI:10.1080/00207548808947948

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

In this paper we develop approximations for the distribution of the total time spent in a dynamic job shop. In particular, using an exponential limit theorem and an heuristic decomposition of open queueing networks, we show that for a large class of dynamic job shops, the total time spent in a dynamic job shop can be approximated by an exponential random variable with an appropriate mean. Approximations for job shops that do not belong to this class are also developed. Numerical results show that the proposed approximations are in general very good. Application of these approximations in the assignment of due-dates is also illustrated.

ISSN:0020-7543    

DOI:10.1080/00207548808947949

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Although the technology exists for more advanced applications of automated guided vehicles in flexible manufacturing systems, the current employment of these vehicles in material handling generally subscribes to a simple mode of operation : single-load-carrying capacity for each vehicle and unidirectional traffic on each route of the system. Through a simulation programme, this study investigates the effect of several key factors related to the automated guided vehicles on the overall performance of a flexible manufacturing system. These are the number of pallets allowed in the system, the number of vehicles used and the carrying capacity of each and the input and output queue capacities of the machining stations; finally bidirectional traffic is allowed in some routes. The results show that there is a strong interaction among these factors and reveal their combined effects on the throughput from a small flexible manufacturing system. Upon the user's request, the simulation program also provides the animated colour graphics of the system to view developments concurrently under the selected decision values through time.

ISSN:0020-7543    

DOI:10.1080/00207548808947950

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Previous studies suggest that performance of a series system may be enhanced if those station(s) having smallest mean operation time requirement(s) and/or smallest variability are placed in the middle of the line. There has been considerable confusion relative to whether this ‘bowl phenomenon’ has to do with the placement of means, variances, or some combination of the two. The results of the current study show that the phenomenon observed is not related to an imbalance in means. Rather, it is associated with an imbalance in absolute variability. Furthermore, it is suggested that the bowl effect vanishes altogether in cases where a minimal level of in-process buffer stock is provided.

ISSN:0020-7543    

DOI:10.1080/00207548808947951

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

In a mechanical workshop a CNC-machining centre is used to perform a large number of point operations on one or more workpieces in a clamp. Both the sequence of point operations and the method of clamping have a strong impact on the total amount of time that is needed to complete each workpiece. In this paper we analyse the efficiency of two clamping methods in the production of automotive engine blocks. The efficiency of these clamping methods is measured in terms of time, which is minimized by determining the optimal sequence of operations required for each method of clamping. A modification of a TSP algorithm has been employed to determine these optimal sequences.

ISSN:0020-7543    

DOI:10.1080/00207548808947952

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

This paper applies Buzen's algorithm to the problem of determining the maintenance float needed to support an operating system withNcirculating units. A maintenance network with load-independent servers is assumed. The operating system availability and maintenance floats are obtained using this iterative algorithm. It is shown that the normalizing constant used in the algorithm can easily be computed for the maintenance float problem by using geometric series. This result is further used to obtain a simple model for the expected number of operating units, thus making it easy to compute the operating system availability for any given N. Buzen's algorithm therefore provides a simple solution to the maintenance float problem.

ISSN:0020-7543    

DOI:10.1080/00207548808947953

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Cams are essential mechanical parts in manufacturing industries. Traditional methods of cam design and production are time-consuming and error-prone. This paper is an effort to try to develop a methodology of computer-aided design and manufacturing of plate cams. The computerized procedure is detailed with accompanying examples.

ISSN:0020-7543    

DOI:10.1080/00207548808947954

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

ISSN:0020-7543    

DOI:10.1080/00207548808947956

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor