摘要:

The efficiency of production systems consisting of a number of interconnected stations can be predicted from the characteristics of the stations when there is no internal storage. Formulae are developed for the efficiency of the basic connections, without and with redundancy. It is shown how the efficiency of more complex systems can be predicted using the basic formulae. The different types of redundancy, parallel, standby and splitting, are compared and it is shown that usually splitting, if feasible, is best. It is indicated how the results can be used to obtain upper and lower bounds on the efficiency with internal storage.

ISSN:0020-7543    

DOI:10.1080/00207546708929778

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

The accuracy of physiological work studies depends only in part on the measuring instrument itself. If the measurement is performed on work which is insufficiently described, the total accuracy of the measurement is decreased. A proper selection of description variables increases the accuracy of physiological work measurement and makes a fairly general prediction of the energy expenditure possible. A model for prediction of energy expenditure from physical data is proposed and has been tested in a number of industrial cases. The accuracy of the result is of the same order of magnitude as a good work study.

ISSN:0020-7543    

DOI:10.1080/00207546708929779

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

Groove wear which occurs in the turning operation is important in its relation to surface finish and tool-life. A new mechanism for groove formation is suggested, which is based on the mechanics of chip formation when cutting with two distinct cutting edges. An experimentally proven method for reducing the tendency to develop grooves is also described.

ISSN:0020-7543    

DOI:10.1080/00207546708929780

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

Experimental results are presented for the piercing of circular holes in sheet metal using pads of conventional rubber or polyurethane. An empirical equation has been obtained for calculating the required loads and an attempt has been made to interpret this equation in terms of rubber hardness and the work-hardening characteristic of the metal. It is shown that the deformation behaviour of the polyurethane is different from that of the rubber and that it is misleading to treat polyurethane as though it is merely a rubber with a higher Shore hardness.

ISSN:0020-7543    

DOI:10.1080/00207546708929781

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

The action of the obstruction type chip former, as used on lathe turning tools, is examined and the significance of the radius of curvature of the chip, imposed by the chip former, is discussed in relation to problems of chip control. The previous estimates of the chip curvature produced in terms of chip former dimensions are briefly reviewed and a new analysis is presented which takes into account the variations of chip thickness and the length of the chip-tool contact region on the tool rake face.

ISSN:0020-7543    

DOI:10.1080/00207546708929782

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

This paper describes the development of a culling force equation for single-point orthogonal cutting which incorporates cutting speed, feed, depth of cut and side-rake angle. Additional cutting force equations are then developed using smaller levels of the machining variables resulting in reduced experimental costs but retention of reliable predictive equations.

ISSN:0020-7543    

DOI:10.1080/00207546708929783

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor

摘要:

The paper reports on two empirical studies into the relationship between a company's sales and its inventories. Two ideas are examined. Firstly, are there economies of scale in the holding of inventories, do large companies hold proportionately lower levels than smaller companies? Secondly, has there been a significant change in the inventory-sales relationship over time, has the increasing emphasis on scientific management led to a change in inventory holding practices?

ISSN:0020-7543    

DOI:10.1080/00207546708929784

出版商:Taylor & Francis Group    

年代:1967

数据来源: Taylor