In the traditional cost-efficiency model, the information about each decision unit includes inputs, outputs, and the input prices are fixed and specific. In practice, the price of the inputs often fluctuates at different times, and these prices for the decision-making unit are time-dependent. By the traditional method, the efficiency of decision units is impossible in the presence of time-depen...

— This paper summarizes ten replacement models which combine tkree basic replacements: (i)age replacement; (ii)block replacement; (in) periodic replacement with minimal repair at failure. The expected cast rates ofeach model are derived, using the usual caktdus method ofprobabitity. As an example, we give an optimum policy to minimize the expected cost rate ofone model

With the evolution of technology, the maintenance of sophisticated systems is of concern for system engineers and system designers. The maintenance cost of the system depends in general on the replacement and repair policies. The system replacement may be in a strictly periodic fashion or on a random basis depending upon the maintenance policy. At failure, the repair of the system may be perfor...

magnetic levitation (maglev) is amongst the most advanced technologies that are available to the transportation industries. it has already been noticed by decision makers in many countries around the globe. contrary to such high levels of interest, there are no practical algorithms available to the engineers and/or managers to assist them in analyzing economics of the maglev systems. therefore,...

this paper studies an m/g/1 repairable queueing system with multiple vacations and n-policy, in which the service station is subject to occasional random breakdowns. when the service station breaks down, it is repaired by a repair facility. moreover, the repair facility may fail during the repair period of the service station. the failed repair facility resumes repair after completion of its re...

replacement of a tractor is an influential factor affecting timely farm operation. the accurate prediction of repair and maintenance costs is essential to selection of a replacement model. this study used empirical data for 60 two-wheel drive (2wd) tractors from astan ghods-e razavi agroindustry. the types and numbers of tractors used were the massey ferguson 285 (17), fiat (10), john deere 314...

this paper is concerned with the economic valuation of the coral reef within kish island in persian gulf of iran. for calculating this value, all components of use and non-use values are estimated and then according to each of them, suitable method has applied. many different evaluation tools such as contingent valuation method, zonal travel cost method, replacement cost, avoided cost method, ...