Imperfect Production Systems With Imperfect Preventive Maintenance, Inflation, And Time Value Of Money

A model that integrates the issues of production, quality, maintenance, inspection, inflation, and time value of money is proposed in this paper. It is assumed that the production system starts in the in-control state producing items of high or perfect quality. However, the process may deteriorate with time and shifts at a random point in time to an out-of-control state and begins to produce non-conforming items. The elapsed time for the process to shift to the out-of-control state is assumed to follow a general distribution. Imperfect preventive maintenance, restoration, and inspection errors are taken into account. Also, inflation, time value of money, and shortage are considered in the proposed model. Numerical examples are presented to illustrate important aspects of the integrated model

Imperfect Production Systems With Imperfect Preventive Maintenance, Inflation, And Time Value Of Money

A model that integrates the issues of production, quality, maintenance, inspection, inflation, and time value of money is proposed in this paper. It is assumed that the production system starts in the in-control state producing items of high or perfect quality. However, the process may deteriorate with time and shifts at a random point in time to an out-of-control state and begins to produce non-conforming items. The elapsed time for the process to shift to the out-of-control state is assumed to follow a general distribution. Imperfect preventive maintenance, restoration, and inspection errors are taken into account. Also, inflation, time value of money, and shortage are considered in the proposed model. Numerical examples are presented to illustrate important aspects of the integrated model

Imperfect Production Systems With Imperfect Preventive Maintenance, Inflation, And Time Value Of Money

A model that integrates the issues of production, quality, maintenance, inspection, inflation, and time value of money is proposed in this paper. It is assumed that the production system starts in the in-control state producing items of high or perfect quality. However, the process may deteriorate with time and shifts at a random point in time to an out-of-control state and begins to produce non-conforming items. The elapsed time for the process to shift to the out-of-control state is assumed to follow a general distribution. Imperfect preventive maintenance, restoration, and inspection errors are taken into account. Also, inflation, time value of money, and shortage are considered in the proposed model. Numerical examples are presented to illustrate important aspects of the integrated model

Imperfect Production Systems With Imperfect Preventive Maintenance, Inflation, And Time Value Of Money

A model that integrates the issues of production, quality, maintenance, inspection, inflation, and time value of money is proposed in this paper. It is assumed that the production system starts in the in-control state producing items of high or perfect quality. However, the process may deteriorate with time and shifts at a random point in time to an out-of-control state and begins to produce non-conforming items. The elapsed time for the process to shift to the out-of-control state is assumed to follow a general distribution. Imperfect preventive maintenance, restoration, and inspection errors are taken into account. Also, inflation, time value of money, and shortage are considered in the proposed model. Numerical examples are presented to illustrate important aspects of the integrated model

Production and Warranty Optimal Period in Deteriorating Production Systems by Considering Inspection of both Manufacturing Equipment and Products Simultaneously

Traditionally high share of production-distribution costs to inventory and supply policy dedicated. The production model of politics is important for a system of distribution, taking into account the actual conditions of production and optimal production parameters influenced. One of these conditions is that the production equipment during production turned out of control and produce defective products. It is possible to change the mode in real terms, and then significantly increase the amount of defective products. Despite these conditions, one of the parameters affecting the demand for products and sales, and consequently the amount of corporate profits is the product warranty. The after-sales service product parameter influencing the willingness of consumers to buy the product. In this work, it consider the potential failure of production equipment, as well as the product warranty, mathematical models of inventory control policy, based on actual production conditions for the production units. This model is aimed at achieving the optimal length of time in each period and for optimum product warranty with respect to maximizing profits per unit of time. In other words, the goal is create an optimal balance between product sales revenue and costs incurred during the period of warranty for the product. In fact, in this article will discuss this model and its resolution

Economic theory and the welfare state : a survey and interpretation.

'I propose here the view that, when the market fails to achieve an optimal state, society will, to some extent at least, recognize the gap, and nonmarket social institutions will arise attempting to bridge it....' (Kenneth Arrow 1963, p. 947). 'Economic theorists traditionally banish discussions of information to footnotes. Serious consideration of costs of communication, imperfect knowledge ... would, it is believed, complicate without informing.... [T]his comforting myth is false. Some of the most important conclusions of economic theory are not robust to considerations of imperfect information' (Michael Rothschild and Joseph Stiglitz 1976, p. 629). 'That any sane nation, having observed that you could provide for the supply of bread by giving bakers a pecuniary interest in baking for you, should go on to give a surgeon a pecuniary interest in cutting off your leg, is enough to make one despair of political humanity' (George Bernard Shaw, The Doctor's Dilemma, 1911).

Preventive maintenance and replacement scheduling : models and algorithms.

Preventive maintenance is a broad term that encompasses a set of activities aimed at improving the overall reliability and availability of a system. Preventive maintenance involves a basic trade-off between the costs of conducting maintenance/replacement activities and the cost savings achieved by reducing the overall rate of occurrence of system failures. Designers of preventive maintenance schedules must weigh these individual costs in an attempt to minimize the overall cost of system operation. They may also be interested in maximizing the system reliability, subject to some sort of budget constraint. In this dissertation, we present a complete discussion about the problem definition and review the literature. We develop new nonlinear mixed-integer optimization models, solve them by standard nonlinear optimization algorithms, and analyze their computational results. In addition, we extend the optimization models by considering engineering economy features and reformulate them as a multi-objective optimization model. We optimize this model by generational and steady state genetic algorithms as well as by a simulated annealing algorithm and demonstrate the computational results obtained by implementation of these algorithms. We perform a sensitivity analysis on the parameters of the optimization models and present a comparison between exact and metaheuristic algorithms in terms of computational efficiency and accuracy. Finally, we present a new mathematical function to model age reduction and improvement factor parameter used in optimization models. In addition, we develop a practical procedure to estimate the effect of maintenance activity on failure rate and effective age of multi component systems

Promoting an Effective Market Economy in a Changing World

In this paper we examine the main challenges in promoting an effective market economy. While the paper ranges widely across the spectrum of economic institutions and policies, the central theme is the importance of macroeconomic stability for economic growth in the medium and long run. Macroeconomic stability may be seen as a public good. Its provision is among the essential responsibilities of the state both in modern market economies and in economies transforming themselves into modern market economies. Following this brief introduction, Section II considers four key aspects of the economic environment of the coming decade: increasing internationalisation; market-orientation; diminished government role; high real interest rates. Section III reviews the reasons why macroeconomic stability matters for economic performance and summarises the key empirical evidence supporting the existence of a causal link. Section IV deals with the design of domestic and international policies and institutions to promote macroeconomic stability and Section V asks how national governments and international institutions can take advantage of the current relatively stable global macroeconomic environment to improve medium-term growth. Section IV concludes. While our discussion will range broadly both theoretically and empirically, we shall emphasise lessons for , and experience from, countries attempting to create a market economy.