摘要:

Considerable attention to the economics of variables acceptance sampling has recently emphasized that the alpha-beta approach to sampling plan design may be far from optimal. Similarly, recent results conclusively show that measurement error manifested as bias (inaccuracy) and imprecision (variability) can have disastrous effects upon the OC curve of a variables sampling plan. This paper quantitatively combines economics and error and clearly illustrates the adverse monetary effects of imperfect measurement in situations where variables acceptance sampling is used

ISSN:0020-7543    

DOI:10.1080/00207547708943110

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Experimental data are presented which demonstrate a strong correlation between tool wear and the signal of a thermocouple located at a position on the cutting tool remote from the cutting edge. A mathematical model is proposed for explaining this relationship between tool wear and- temperature. The model is supported by good statistical agreement between the data and the form of the proposed equation. For a total of nine different machining conditions with replications for several of the conditions, the correlation coefficient ranged in value between 0·837 and 0·978.

ISSN:0020-7543    

DOI:10.1080/00207547708943111

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Several extensions to the capacity rating (CR) methodology are developed in this paper. The CR index is related in analytical models to the flow of work which is achieved over a planning period for both single and tandem work centre configurations. Statistical dependency between workload and availability is discussed and included in the flow models. Implications of applying the methodology to a series of periods in a planning horizon are clarified. Results collectively provide direction in applying the CR methodology in the planning process

ISSN:0020-7543    

DOI:10.1080/00207547708943112

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

This paper illustrates a case study of forecasting daily traffic levels at branch banks, where many behavioural and business factors are present. Many influences are not equally spaced over, which reduces the effectiveness of traditional time series approaches. To handle this problem, a univariate time series ARIMA model is developed mid then dummy variables are added to incorporate exogenous effects that are not captured by the projection ARIMA model. The results indicate that a more adequate representation of the customer traffic pattern has been obtained by combining the two modelling approaches

ISSN:0020-7543    

DOI:10.1080/00207547708943113

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

This paper demonstrates problems in allocating inter-station inventory capacities in unpaced production lines with heteroscedastic processing times. Simulations were performed to show the effects of total work-in-process inventory capacity, relative inter-station inventory allocations and pattern of processing time variances upon production rate, work station idle times and time to complete a product. Trade offs among the three performance measures were observed and deficiencies in intuitive strategies for redesigning lines were deduced.

ISSN:0020-7543    

DOI:10.1080/00207547708943114

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The method given in this note is typically applicable to those inventory problems where the demand varies from one time period to another time period, and where the arrival of supplies is not restricted to coincide with the beginning of a time period. The procedure assumes that the solution of the inventory problem is available and then the procedure is applied for improving the solution. An example has been solved to illustrate the method

ISSN:0020-7543    

DOI:10.1080/00207547708943115

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

A probabilistic periodic review model has been developed for an inventory system with deteriorating items. The model is derived for any general rate of deterioration. As particular cases, both the constant and varying rate of deterioration are considered. An expression has been derived for the optimum lot-size. An example is given to show the solution form

ISSN:0020-7543    

DOI:10.1080/00207547708943116

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

On many machine tools the set-up times are sequence dependent; that is, the time to set-up for the new part is dependent upon the part for -which the machine is currently set-up. In scheduling lots on the machine, the set-up time is often a significant component of the total time required to complete each lot. Set-up times are frequently not available to the production scheduler, and when they are, they frequently are only averages which conceal the sequence dependency of the set-up times. In this paper, we first develop a procedure that classifies set-up operations and predicts the set-up times and we then develop a method for sequencing the jobs so as to minimize the total set-up time. An example using real world data is used to illustrate these procedures

ISSN:0020-7543    

DOI:10.1080/00207547708943117

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

Equations for the efficiency of a single-acting impact forming machine are derived by representing it as an equivalent single-degree-of-freedom spring-mass system. The deformation load is approximated by various shapes of the force pulse. The effects of the mass ratio, period ratio and the machine-structure parameters on the process efficiency are studied. The interaction between the input momentum and energy is explored. The influence of damping on the efficiency is also investigated. The analysis shows that for achieving a high level of efficiency the time duration in which deformation is completed should be equal to or greater than the natural period of the machine. It is also found that damping improves efficiency when deformation is completed in a time reasonably shorter than the natural period of the machine. Maximum efficiency is attained when all the momentum associated with the falling platen is transferred to the billet

ISSN:0020-7543    

DOI:10.1080/00207547708943118

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The purpose of this paper is to provide an overview of the machine requirements problem. The problem is described and a classification scheme is presented to categorize alternative approaches which might be used to formulate and analyse the problem. In addition, this article discusses the basic analytical approaches to the problem which have been reported in the literature, and relates these approaches to the problem's classification scheme. Conclusions are drawn us to strengths and weaknesses of the approaches, as well as to potential research directions

ISSN:0020-7543    

DOI:10.1080/00207547708943119

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor