摘要:

These investigations were carried out to determine possible correlations between the EDM machining parameters (pulse on, current) and the machineability components (stock removal, electrode wear, overcut, surface finish and surface integrity). The surface integrity of the component depends on its conformity to tolerance, its surface finish and the metallurgical subsurface characteristics. The present work indicates a correlation between the overcut (gap B) and the total thickness of the damaged surface layer (white layer and heat affected zone)

ISSN:0020-7543    

DOI:10.1080/00207548108956635

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

The trials of coping with negative aspects of behaviour such as absenteeism, lateness, and labour turnover have persuaded many companies to abandon the assembly line mode of mass production. Job enlargement exercises have demonstrated the benefits of assigning the building of a complete unit to one operator, thereby eliminating the co-ordination problems associated with dependent stages, but unless accompanied by a radical reappraisal of methods this may lead to a large increase in standard assembly time per unit.

ISSN:0020-7543    

DOI:10.1080/00207548108956636

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

The potential performance of two different ways of designing truck assembly systems, namely line and dock assembly, are analysed. The line system denotes assembly at a mechanically paced moving belt with fixed items, divided in several one-worker stations with a common station time around 20 minutes and located in parallel with up to three other stations. The dock system denotes assembly at stations with typical station times around 4 hours; the items are moved between stations by the workers, who are divided in groups of around ten persons assembling complete trucks. Theoretical models for these specific systems are presented, which together with the results are applicable to more general situations.

ISSN:0020-7543    

DOI:10.1080/00207548108956637

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

In October 1904 an article was published titled ‘Jobshop planning’, describing a rather simple but. effective manual system. From that time onwards quite a number of workshops within Philips have adopted production control systems based on these principles. The jobshops meant here manufacture spare parts, complete machinery and fine mechanical tools in small series, or single items on customer orders; 40 to 150 craftsmen were employed in each of them. What we wanted to achieve was short and reliable delivery times and a high utilization of production capacity. In ten of these jobshops, operating the system for periods of one to four years, the performances were inventorized. However, the fair results achieved seemed to be in contradiction to theoretical studies made at the same time, Therefore in addition to the survey an investigation was made as to why these differences occurred.

ISSN:0020-7543    

DOI:10.1080/00207548108956638

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

This study develops a mathematical model which describes the learning effect in a production process where batches of different sizes are produced. The model separates set-up time from production time, although for the estimation of its parameters these times do not have to be recorded separately. The data required to estimate the parameters of the model is commonly accumulated in organizations, and includes the size of consecutive batches and the respective times for their production.

ISSN:0020-7543    

DOI:10.1080/00207548108956639

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

This paper presents a heuristic procedure for designing paced production lines with stochastic task times. The procedure adopts explicitly the objective of minimizing the sum of incompletion cost and labour cost. Basically, the first stage of the procedure uses a probabilistic procedure to generate many promising line designs: this probabilistic procedure is conceptually related to the procedures of Arues (1960) and Tongc (1965). The procedures second stage uses the Kottas-Lau (1976) cost model to evaluate the operating costs of the generated line designs and to identify the economical ones. Extensive tests with the computerized procedure using randomly generated-test problems have indicated that the procedure can produce very good line designs with modest computer time

ISSN:0020-7543    

DOI:10.1080/00207548108956640

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Consider a production centre receiving orders for several products. Assuming the first two moments of the processing times of the products as known and given the profit per unit of each product, the model provides a basis for selecting the optimal mix of job orders to be accepted. In particular, the main feature of the optimal solution is that it will in most cases call for accepting job orders from a wide spectrum of classes

ISSN:0020-7543    

DOI:10.1080/00207548108956641

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Two formulae to give the mean and the standard deviation of job flow-times are derived from the machine number, the load ratio, the required number of operations, and the mean and the standard deviation of processing times, which specify the characteristics of a job shop. On the basis of the two formulae, a method of due-date assignment which contains a due-date adjustment factor is proposed. The assignment method is combined with the sequencing procedure to construct the total scheduling system for reducing job tardiness. Two new dispatching rules are presented as the second phase of the system. The experimental comparison shows that the efficiency of the proposed systems can be better than the conventional scheduling systems

ISSN:0020-7543    

DOI:10.1080/00207548108956642

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

This paper is intended to show that the inverse Gaussian distribution can lie effectively used to approximate the lead time demand in inventory control problems. The computations involved with this approximation are shown to be simple. Some pertinent properties of the inverse Gaussian distribution are summarized. Numerical examples are given for a few cases of distributed demands coupled with distributed lead times and in each case the inverse Gaussian approximation results are compared with the exact and/or other approximations.

ISSN:0020-7543    

DOI:10.1080/00207548108956643

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

ISSN:0020-7543    

DOI:10.1080/00207548108956645

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor