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Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 94-95). Also available via the Internet.

Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 58-59). Also available on the World Wide Web.

An algorithm is developed to determine the optimal component replacement rules to follow in managing a particular class of equipment. The work follows basically the models developed previously by S.E. Dreyfus and R.A. Howard. However, a different Markov state description has been used to extend the application of these models to systems of more than one component subject to stochastic failure and for which the failure of any component renders the entire system inoperative. The model, in effect, selects optimal replacement alternatives as individual components fail, under the uncertainty of further failures occurring in the same transition interval. The model was programmed for an I.B.M. 360/67 computer and the results for a hypothetical problem were checked through renewal theory. / Forestry, Faculty of / Graduate

This thesis contends that equipment replacement analysis should consider the implications of technological change since a like for like replacement is unrealistic with the current state of technological change. The major effects of improvements are a decrease in salvage value and opportunity expense of not implementing the latest innovations. The improvements appear as gradual changes and as major breakthroughs. Technological forecasting may be accomplished by several different methods including the Delphi method, analogy, and trend interpolation. A discussion of these methods and sources of information are given. The replacement model uses a future worth analysis, continuous discounting, discrete cash flows, a range of planning horizons, and incorporation of tax effects. The model was implemented using a BASIC program with graphics capability. The inputs are current year, initial cost of the equipment, the first years operating cost, regular tax rate, capital gains tax rate, depreciable life (as defined by the ERTA), rates of gradual change, number, dates and effect of major breakthroughs. A discussion of the sensitivity of the model to the various inputs is also given. / Master of Science

No description available.

No description available.

Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 56-59). Also available on the World Wide Web.

This dissertation develops an economic equipment replacement model suitable for Flexible Manufacturing Systems (FMSs). An FMS represents an integrated machining system which produces multiple products and utilizes multiple inputs including avital materials handling system. The system's interactive nature defies traditional replacement works which are confined to one-for-one as well as like-for-like situations. The model developed in this work addresses the issue of multiple machine replacement. Considerations incorporated include layout, transportation, materials handling capacity, flexibility, capacity expansion/contraction, obsolescence and deterioration, inputs substitution, and equipment depreciation. This model is demand driven. The optimality criterion is the maximization of the after-tax future worth of the system at the end of a specified planning horizon. The 1983 ACRS rules are used. Illustrative examples are provided throughout. / Ph. D.

Thesis (MBA)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: The replacement of earthmoving machines forms a significant portion of the annual capital expenditure on South African mines. The decision on the timing of the replacement varies substantially between different operations, but frequently it is not based on any scientific study or analysis. The reason for this is that most textbooks propose complex calculations for the determination of an optimal replacement point, and subsequently the mathematical effort serves as a deterrent to those who are tasked with replacement evaluation. This study proposed a simple graphic method which is suitable for everyday use, and which can quickly be adapted when conditions change. The model furthermore makes provision for the analysis of the replacement of both the current machines (the so-called defenders) as well as an evaluation of potential replacement machines (the so-called challengers). In addition, the model also makes provision for the incorporation of non-cash factors, such as productivity and reliability. / AFRIKAANSE OPSOMMING: Die jaarlikse vervanging van grondversuiwing masjienerie maak 'n groot deel uit van die kapitaalplan van die meeste Suid-Afrikaanse myne. Die metode van besluitneming oor die presiese tydsberekening van die vervanging verskil ook tussen die verskillende organisasies, maar dit is selde gebaseer op 'n wetenskaplike analiese. Die rede hiervoor is dat die meeste handboeke komplekse wiskunde modelle voorstel vir die berekening van 'n optimate masjien vervangingspunt. The kompleksiteit gee daartoe aan dat baie nie kans sien om dit te probeer doen nie, en gevolging wegskram van enige analise. Hierdie studie projek stel 'n eenvoudige grafiese model voor vir allerdaagse gebruik, wat ook vinning gewysig kan word as toestande verander. The model maak ook voorsiening vir die analise van beide die huidige masjien (die sogenaamde verdediger) se optimale vervangingspunt, sowel as die evaluasie van potentiele nuwe masjiene (die sogenaamde aanvallers.) Die model maak verder ook voorsiening vir faktore wat nie normaalweg in geldwaarde beskryf word nie soos byvoorbeeld produktiwiteit en betroubaarheid.