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This paper aims to investigate the optimization of the replacement with minimal repair policy for a system which experiences a time horizon of random length. Under such policy system replacement occurs at multiples of some period while minimal repair is performed at system failure between two successive replacements.

The objective function is the expected total cost composed of minimal repairs and replacements costs. A simple and compact expression is derived for the expected total costs and conditions under which an optimal replacement period exits are given. For sake of illustration, a numerical example is provided.

The paper finds that by the recent great technological development, the life cycle of present products is seen to be reduced more and more. This has motivated the development of maintenance optimization models for systems which experience an exact finite time horizon.

To ensure the benefits from the improved technologies, the information concerning the technological change must be taken into account. Such information is based on technological forecasting and difficult to obtain and merely rely on uncertainties.

The purpose of this study is to gain some insights into the number of shortages resulting from two alternative demand allocation schemes between a contractor (machine M₁) and subcontractor (machine M₂), on the one hand, and from inventory accumulation, on the other hand. The shortages stem from random machine breakdowns, and each machine undergoes preventive maintenance. The motivation behind inventory accumulation is to allow demand to be fulfilled even when both machines are down.

The number of shortages stemming from all scenarios under consideration was established via computer simulation with the Arena^© language.

For demand allocation that remains unchanged for the duration of the planning horizon and constant reliability of M₁, it was found that, the less reliable M₂ is, the more biased in favour of M₁ will be the optimal demand allocation and the greater will be the number of shortages. Moreover, both dynamic demand reallocation over the planning horizon and inventory accumulation result in a substantial reduction in shortages.

The results are representative of the specific data, which were assumed in the simulation models. Nevertheless, this methodology is recommended for this type of analysis, as it is highly flexible and can take into account many practical considerations, which an analytical approach cannot.

Within the context of unreliable production machines, the most important practical implication of this study is that the dynamic reallocation of demand between a contractor and subcontractor, along with inventory accumulation, both have the potential to yield important reductions in the number of shortages.

The subject‐matter of this paper was not previously reported in the literature. Furthermore, the insights gained as a result of this study can yield substantial benefits to companies in terms of improving their service levels as measured by reduced shortages.

The purpose of this paper is to propose a stochastic optimisation model for integrating service and maintenance policies in order to solve the queuing problem and the cost of maintenance activities for public transport services, with a particular focus on urban ropeway system.

The authors adopt the following approaches: a discrete-event model that uses a set of interrelated queues for the formulation of the service problem using a cost-based expression; and a maintenance model consisting of preventive and corrective maintenance actions, which considers two different maintenance policies (periodic block-type and age-based).

The work shows that neither periodic block-type maintenance nor an age-based maintenance is necessarily the best maintenance strategy over a long system lifecycle; the optimal strategy must consider both policies.

The maintenance policies are then evaluated for their impact on the service and operation of the transport system. The authors conclude by applying the proposed optimisation model using an example concerning ropeway systems.

This is the first study to simultaneously consider maintenance policy and operational policy in an urban aerial ropeway system, taking up the problem of queuing with particular attention to the unique requirements public transport services.

This paper aims to propose an approach for the optimization of imperfect preventive maintenance and corrective actions performed on a single machine. After maintenance, the machine returns to an age between “as good as new” and “as bad as old”.

The approach is based on fuzzy logic and simulation‐based optimization. Fuzzy logic is preferred over crisp logic because it is relatively easy to implement in this situation considering that the human factor is hardly interpreted by analytical methods because of its unpredictable nature. Simulation‐based optimization is used to have a more reactive and accurate tool for practitioners.

Taking into account the impact of the imperfections due to human factors, the period for preventive maintenance, which minimizes the expected cost rate per unit of time or maximizes the availability of the system, is evaluated by the simulation‐based optimization.

Different and more realistic maintenance levels must be considered and the traceability of a specific system could be used to determine the most appropriate failure law. For this study, cost reduction was considered as the priority, but the model can be adjusted according to the user's preferences.

This paper considers a single repairable machine as a system that undergoes periodic preventive and corrective maintenance actions. Considering maintenance imperfections, rule‐based fuzzy logic can be integrated into the maintenance program to determine the times for the periodic preventive maintenance actions.

Considering human factors in maintenance programs is indispensable to assure more accurate and realistic results. However, due to the difficulty engendered by their modeling, most theoretical maintenance models do not consider these factors. Therefore, the proposed fuzzy model in the paper can be an important tool to include them.

The great majority of academic libraries find themselves in a vast and often unmarked territory between two polar sets of goals and aspirations. These two poles could be represented by the model of the great research library, on the one hand, and the discount store, on the other. In choosing the first ideal, the library decides to acquire as broad a selection of research materials as possible, including infrequently used primary materials (census records, publications from limited editions, personal manuscripts, and unpublished pamphlets) in order that researchers may, at least in theory, find the collection all‐ or nearly all‐sufficient. Holders of this view point with pride to the contents of the catalog. At the other pole, the library sets out to be as responsive to demand as possible, to provide more and more of the materials which “move off the shelves” and, like the discount store, to discontinue stock items which are less popular than something more attractive which might replace them. Advocates of this view point with pride to the swarming circulation desk.

Do Multinational Enterprises (MNEs) implement managerial strategies oriented towards Sustainable Development (SD) to respond to an essentially marketing issue? The article answers this question by showing that the commitment to SD implies an evolution of the marketing paradigm towards some more responsible marketing. More precisely, this commitment implies a vision of marketing in terms of competences, focusing mainly on the translation of SD values into customer benefits that might bring a lasting competitive advantage. It presupposes a genuine integration into the companies’ marketing strategies and implies that an essential boundary is set, satisfying customers and maintaining and improving the balance of the quality‐price‐services ratio in the commercial offer on the market.

The paper attempts to gain a better understanding of the reasons for advertisers to use nudity in European advertising campaigns and, more precisely, whether a print ad that uses nudity is more or less effective than an ad without nudity in the Czech Republic, Spain, and France.

An experiment carried out in three European countries (Czech Republic, Spain, France) exposes young consumers to an experimental magazine containing an advertisement that shows either a woman's face or her topless body.

Nationality does not appear to influence preferences for advertisements with or without nudity. Although differences emerge among the three countries in attitudes toward the ad (Aad), they are independent of the ad type and consistently reflect the same trends within each country. Gender influences Aad, and women adopt more negative Aad when they see nudity compared with when they do not, in contrast with men, regardless of their country.

Attitudes toward advertising in general vary significantly among European countries, even for seemingly homogeneous targets. Specific adaptations likely are needed not just with regard to nudity but more generally in terms of the content of ads.

Advertisers that question the relevance of nudity in their advertising campaigns should take great care to define their target market by gender – even more so than in terms of the European country in which the advertising will appear.

Women adopt more negative attitudes toward advertisements that use sexy female models than do men, and this effect is independent of nationality in a European context.

Academic librarians are frequently called upon to provide instruction in relatively unfamiliar disciplines. This article presents introductory information for librarians providing bibliographic instruction (BI) in the field of psychology. Its primary purpose is to identify key readings from the library science and psychology literature that provide a basis for informed delivery of psychology BI. These works are fully identified in the list of references at the end of this article. Because the primary purpose of discipline‐specific bibliographic instruction is to teach the skills necessary for retrieval of the products of scholarship in that discipline, we begin with a discussion of scholarly communication and documentation, which describes how scholars and researchers within psychology communicate research findings and theoretical developments in the discipline. The major emphasis of this article is on formal, group instruction rather than individualized instruction, although much of the information will be applicable to both types.

Current library literature offers little advice for the selection of science books for the general public. Most articles and books concern the primary scientific literature, produced by scientists for their peers, information most useful to managers of sci‐tech libraries. The popular or general‐interest science book has apparently been overlooked by both science and general librarians. Yet this category of books is interesting and important in its own right,andopportunitiesabound for investigation into their selection and use.