摘要:

Field service managers are often faced with the problem of balancing the number of technicians, territory size, and field service quality. This paper presents an approximate state-dependent queuing model that can help field service managers make these tradeoffs. Simulation experiments over a variety of field service environments demonstrate that this model is quite accurate for predicting mean travel time and mean response time. The approximate queuing model has been imbedded in a decision support system and implemented by a Fortune 100 company. Management found the decision support system very useful in making important field service decisions.

ISSN:0740-817X    

DOI:10.1080/07408179208964194

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The cut-off dimensioning problem is characterized by the complexity of the problem, and by environmental uncertainty. A solution is proposed using deeomposition into lateral modules and vertical layers Lateral decomposition permits the distribution of expertise, hence the reduction in the complexity of the problem. The vertical decomposition permits greater expert decision-making, hence the reduction in uncertainty. A synergy of three knowledge representation methods is used: Declarative knowledge is used for rule-based reasoning, heuristic methodologies are used for the deterministic, context-dependent decision-making, and strictly algorithmic procedures are used for the tasks inclined to data abstraction and mathematical manipulations. The frame is used as the common knowledge carrier among all three tasks.

ISSN:0740-817X    

DOI:10.1080/07408179208964195

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The human body changes its physiological functions throughout the 24-hour day. During waking hours, the body is prepared for physical work, while during the night sleep is normal. Attitudes and behavior also change rhythmically during the day. Work should be arranged to least disturb physiological, psychological, and behavioral rhythms to avoid negative health and social effects and to avoid reductions in work performance (Kroemer, Kroemer and Kroemer-Elbert, [20]).

ISSN:0740-817X    

DOI:10.1080/07408179208964196

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

A modular influence diagram model is proposed as a decision-analytic framework for reasoning about diagnostic testing in the manufacture of mechanical products. The influence diagram ties product design, manufacturing, and testing decisions to field quality, costs and risks. The decision-analytic theory of “expected value of information” is used to evaluate the cost-benefit of alternate testing systems. The structure of the model highlights research directions for engineering economics in evaluating cost-benefit tradeoffs in the product cycle from design, to manufacturing, marketing and field service. An implementation in the IDES (Influence Diagram Based Expert System) illustrates the potential of applying such a planning model to real-time diagnostic decisions in the manufacture of mechanical components for high-speed printers.

ISSN:0740-817X    

DOI:10.1080/07408179208964197

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

This paper uses a general maintenance problem and a new policy iteration algorithm to solve most semi-Markovian maintenance models. This algorithm decomposes the maintenance process into a deteriorating process and a sequence of replacement and repair actions so that the number of states involved in the decision process is less than the state space of the unmaintained process. Consequently, the number of equations to be solved at every iteration step can be substantially reduced.

ISSN:0740-817X    

DOI:10.1080/07408179208964198

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

A model in which jointly optimal stocks of material and finished products are to be chosen is reexamined. While it costs less to hold material, a certain percentage of the random demand not immediately satisfied by previously finished products is lost. We pay particular attention to the dependence of the optimal stocks on the initial ones, which assumes an interesting form. For example, if the stock of finished products is high but the combined stock is low, die quantity of material ordered depends on the stock of finished products.

ISSN:0740-817X    

DOI:10.1080/07408179208964199

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Two statistical models are evaluated for auditing work measurement data against MJL-STD-1567A accuracy criteria. The simple linear regression and paired data models are contrasted and their theoretical appropriateness is discussed. The modeled variable, in both cases, is measured in time units rather than ratio units. Modifications of both models are proposed.

ISSN:0740-817X    

DOI:10.1080/07408179208964200

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

This paper develops an efficient analytical method for the analysis of an n-machine production line with unreliable machines and random processing times. The behavior of the n-machine line is approximated by the behaviors of the (n — l) two-machine lines based on the decomposition. Simulation and numerical experiment show that the analytical method works well and is very efficient.

ISSN:0740-817X    

DOI:10.1080/07408179208964201

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The existence of intercellular moves due to bottleneck machines is a major road block to higher productivity gains in cellular manufacturing systems. One solution to this problem is the formation of a separate cell containing all bottleneck machines from different machine cells (hybrid cell). The formation of hybrid cell is based on the premise that the concentration of bottleneck machines in a single cell makes them more accessible to exceptional parts and simplifies the material flow. This paper presents a procedure for performance evaluation of hybrid cells with the purpose of verifying this premise. The procedure uses the sum of intercellular and intracellular material handling costs as a performance measure.

ISSN:0740-817X    

DOI:10.1080/07408179208964202

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

We investigate a canning problem (Golhar and Pollock [2]) to study the effect of a reduction in process variance on the production cost. Exact and approximate relationships are developed for cost reduction as a function of economic parameters when the fill is a normally distributed random variable and process settings are optimized.

ISSN:0740-817X    

DOI:10.1080/07408179208964203

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor