摘要:

Four hundred and twenty-seven reported accidents in the course of repetitive, self-paced work in the machine shop of a light engineering factory were analysed for time of occurrence. Four critical peak periods were found. During these periods observational studies of variability of speed of operation were conducted, particularly on lathes, which revealed thai machine loading times varied more than cutting times. This was followed by a case study of variability of accuracy of hand movements. Unsuccessful Hand Movements (UHMs) were found to occur more often during the critical periods than at other times of the day. The data are interpreted in terms of rate of gain of information, fatigue and boredom.

ISSN:0020-7543    

DOI:10.1080/00207547008929833

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

Many production lines can be viewed as a series of work stations with inter-station storage (or buffers). Consideration of production lines as a series of finite queues permits evaluating inefficiencies in terms of the queue capacity at each station; the mean servicing (or work) times at each station and their distribution; and the numbers of stations.

ISSN:0020-7543    

DOI:10.1080/00207547008929834

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

Radial turning tools extend as a result of cutting forces and temperature. The effect on work size is examined and some experimental results are compared witK estimates based on a simple model. Some methods of measuring tool extension both directly and through its effect on work size are described and conditions are discussed under which this effect may be minimized.

ISSN:0020-7543    

DOI:10.1080/00207547008929835

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

Experiments are described in which hollow cylinders of mild steel were subjected to stalic compression, both where the operation was stopped freqnenily to effect re-lubrication, and where the operation was continuous. Previous observations relating to the rolling of material from the walls of the specimen onto the compression plaiens are illustrated and discussed. The effects of specimen/platen friction on the interpenetration of the “dead meta zones“ or “pressure cones“ and the resultant effects upon force-displacement characleristics and axially inhomogeneous deformation of the specimen are demonstrated. Further tests carried out dynamically at both room and elevated temperature are described. The mechanism whereby a sharp “tongue“ of material is caused to project from the inner wall at high fractional reductions —also observed in ihe use of Plasticenef specimens—is illustrated.

ISSN:0020-7543    

DOI:10.1080/00207547008929836

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

To look for patterns in the organisation of engineering design departments, a pilot comparison has been made of numerical information on the employment of engineers, draughtsmen and technicians on design and supporting development in a variety of firms. The results indicate patterns in the distribution of designers by salary level and in the proportion of designers engaged in co-ordination of design. Some pattern also appears in the relative costs of design, but none of the results appears to have any relation to the duration of design or to the number of engineers relative to the number of draughtsmen and technicians.

ISSN:0020-7543    

DOI:10.1080/00207547008929837

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

In this part of the paper, a method is given for allocating least-cost component tolerances to engineering designs whose functional requirements lead to systems of simultaneous tolerance equations, having one or more component tolerances occurring in more than one tolerance equation. These least-cost tolerances are obtained by minimising the total cost of achieving them, using the method of Lagrange's undetermined multipliers. Methods of solving the resulting non-linear equations in Lagrange's multipliers are given. A notation for the treatment of simultaneous tolerance equations is developed. The procedure is illustrated by examples.

ISSN:0020-7543    

DOI:10.1080/00207547008929838

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

The purpose of this paper is two fold: first to provide a method for evaluating projects which have an income pattern describable by a polynomial function of time, and to provide a means for evaluating projects which exhibit a yearly growth or decline in earnings while maintaining the ability to account for the time pattern of earnings, and second to bring forth an assessment technique which will reflect the possibility of attaining various levels of income for each of the periods of interest. Methods utilized in developing the various models are based on the concept of dynamic return.

ISSN:0020-7543    

DOI:10.1080/00207547008929839

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor