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Newspaper cartoons can graphically display the results of ambiguity in human speech; the result can be unexpected and funny. Likewise, computer analysis of natural language statements also needs to successfully resolve ambiguous situations. Computer techniques already developed use restricted world knowledge in resolving ambiguous language use. This paper illustrates how these techniques can be used in resolving ambiguous situations arising in cartoons.

The purpose of this paper is to properly plan the preventive maintenance schedule for multiple elevators and optimize the number of maintenance workers.The total amount of the maintenance cost consisting of the labor cost, the part cost, and the quality cost (the loss evaluated in terms of cost, to be incurred when an elevator breaks down) is to be minimized.The method is presented of setting up the optimal preventive maintenance schedule on a long‐term basis by rescheduling the contents of schedule dynamically and flexibly in accordance with the ever‐changing maintenance conditions, taking the possibility of the future occurrence of failure into consideration. From numerical experiments, the validity of the proposal procedure for planning the preventive maintenance schedule and the effectiveness of considering the possibility of the future occurrence of failure in planning the schedule are shown, and the optimal number of maintenance workers can be decided.

The purpose of this paper is to demonstrate the application of analytic network process (ANP) as a methodology to make multiple criteria decision in selecting the most appropriate maintenance strategy for organizations with critical manufacturing requirements.

Maintenance strategy selection problems are multiple criteria decision making (MCDM) problems which consist of many qualitative and quantitative characteristics. For solving MCDM problems, the ANP is highly recommended as it considers the interdependent influences among and between the various levels of decision attributes. In this research paper, the ANP method is used to select the optimum maintenance strategy in a cement industry in India.

The ANP method can be used as an effective tool for the evaluation of possible alternatives in maintenance strategy decision problems by considering the dependency among the strategic factors.

As illustrated in this paper, ANP method can also be used in other industries for adopting the optimum maintenance strategy to enhance the business performance by decreasing the losses associated with equipment effectiveness.

The major contribution of this research is the successful development of the comprehensive ANP model for the cement plant. ANP model incorporates diversified variables of the cement plant supply chain and includes their interdependencies. The proposed ANP model in this paper, not only guides the decision makers in the selection of the best services but also enables them to visualize the impact of various criteria in the arrival of the final solution.

The model can be extended to certain other manufacturing sectors as the future scope of research and may assist in obtaining a clear idea regarding the status of current maintenance strategies. It should be carried out with a larger number of firms in India focusing on small and medium firms to confirm these results and reinforce their applicability to these kinds of firms. Studies of such a nature would help in identifying successful organizational factors or successful maintenance practices that lead to superior performance.

This paper explores the value of implementing ANP as a decision making method in maintenance strategy, which is currently not a prevalent method.

This paper aims to report the study of a fluid buoy system that includes wave effects, with particular emphasis on validating the numerical results with experimental data.

A fluid–solid coupled algorithm is proposed to describe the motion of a rigid buoy under the effects of waves. The Navier–Stokes equations are solved with the open-source finite volume package Code Saturne, in which a free-surface capture technique and equations of motion for the solid are implemented. An ad hoc experiment on a laboratory scale is built. A buoy is placed into a tank partially filled with water; the tank is mounted into a shake table and subjected to controlled motion that promotes waves. The experiment allows for recording the evolution of the free surface at the control points using the ultrasonic sensors and the movement of the buoy by tracking the markers by postprocessing the recorded videos. The numerical results are validated by comparison with the experimental data.

The implemented free-surface technique, developed within the framework of the finite-volume method, is validated. The best-obtained agreement is for small amplitudes compatible with the waves evolving under deep-water conditions. Second, the algorithm proposed to describe rigid-body motion, including wave analysis, is validated. The numerical body motion and wave pattern satisfactorily matched the experimental data. The complete 3D proposed model can realistically describe buoy motions under the effects of stationary waves.

The novel aspects of this study encompass the implementation of a fluid–structure interaction strategy to describe rigid-body motion, including wave effects in a finite-volume context, and the reported free-surface and buoy position measurements from experiments. To the best of the authors’ knowledge, the numerical strategy, the validation of the computed results and the experimental data are all original contributions of this work.

One of the main problems, when choosing between preventive or corrective maintenance for the production and maintenance departments in the eight firms studied, is to attempt to establish the state of a particular production system or individual production line. In order to carry out a cost analysis it is imperative to be able to measure how preventive maintenance will both reduce the deterioration of the state of the object and improve the state of the object at the point in time that the maintenance is carried out. This can be explained by the fact that the departments lack methods for measuring and estimating the effects. The model presented in this paper determines whether to schedule preventive maintenance and the model trades off the capital costs of preventive maintenance and the sum of corrective maintenance and down‐time costs based on the production line’s state.

This research aims to examine the relevant literature related to maintenance performance measurement in the manufacturing sector. In the process, innovative approaches and models utilized to measure and manage maintenance performance in manufacturing operational settings are classified and examined. Based on this investigation, future research directions and themes are identified.

A database of 251 peer‐reviewed publications, published during the last 30 years, was utilized for the purpose of this research. The published works included contributions from both practitioners and scholars.

This literature review‐based research revealed important themes related to evolution of maintenance performance management. These themes focus on the effective utilization of maintenance resources, information systems support, and human factor management. Based on this literature review, a conceptual framework, which traces the different operational and organizational facets of the evolution of maintenance performance management, is offered.

Based on the findings of this study, it is concluded that the area of maintenance performance and management is in need of more future systematic research efforts aimed at solidifying theoretical constructs and promoting the utilization of more practical applications.

Findings derived from this investigation have relevant manufacturing implications. In this context, understanding the different approaches to maintenance performance measurement and management, as utilized in manufacturing organizations, is critical to these organizations' performance improvement efforts.

Understanding the types and scopes of the different approaches and models utilized to manage and measure maintenance performance in manufacturing operational settings is important in light of the growing competitiveness of the manufacturing sector.

The purpose of this paper is to provide comprehensive information on preventive maintenance (PM) planning and methods used in the industry in order to achieve an effective maintenance system.

The literature review is organized in a way that provides the general overview of the researches done in the PM. This paper discusses the literatures that had been reviewed on four main topics, which are the holistic view of maintenance policies, PM planning, PM planning concept and PM planning-based in developing optimal planning in executing PM actions.

PM policy is one of the original proactive techniques that has been used since the start of researches on maintenance system. Review of the methods presented in this paper shows that most researches analyse effectiveness using artificial intelligence, simulation, mathematical formulation, matrix formation, critical analysis and multi-criteria method. While in practice, PM activities were either planned based on cost, time or failure. Research trends on planning and methods for PM show that the variation of approaches used over the year from early 1990s until today.

Research about PM is known to be extensively conducted and majority of companies applied the policy in their production line. However, most analysis and method suggested in published literatures were done based on mathematical computation rather than focussing on solution to real problems in the industry. This normally would lead to the problems in understanding by the practitioner. Therefore, this paper presented researches on PM planning and suggested on the methods that are practical, simple and effective for application in the real industry.

The originality of this paper comes from its detail analysis of PM planning in term of its research focus and also direction for application. Extensive reviews on the methods adopted in relation to PM planning based on the planning-based such as cost-based, time-based and failure-based were also provided.

The purpose of this paper is to examine the role of maintenance in improving company's competitiveness and profitability. In the first part the paper aims to discuss the potential improvement areas from the company perspective. Second part of this paper examines maintenance impact on company's business.

An empirical case study was utilized aiming to provide an understanding of the role of maintenance in improving company's business. The empirical data for this study were collected from a Slovenian textile company. A gap analysis was used in order to address the research problem and to identify potential improvement areas.

Based on the gap analysis, the results suggest that from respondents’ points of view, maintenance practices related to condition-based maintenance approach represent the highest opportunity for improvement. The most notable empirical results of the case study showed that around 3 per cent of additional profit could be generated at weaving machine, especially if all unplanned stoppages and loss of quality due to decrease in the productivity would be prevented.

This paper demonstrates to managers the potential benefits of maintenance policy in terms of productivity, quality and profitability. In this regard, this paper builds on a premise that company can gain higher performance benefits using more effective maintenance policy.

The proposed conceptual model contributes to the existing literature by showing the interactions between maintenance and company's competitiveness and profitability. Empirical findings of this study therefore, acknowledge maintenance's potential of increasing the overall profit. In addition this study advances prior studies by utilizing a gap analysis which is rare in this type of research.

The purpose of this paper is to show that the increase in competitiveness in relation to requirements regarding quality, availability, safety and service has contributed to demonstrating the need to change the concept of maintenance from a tactical issue to a strategic subject in companies. In order to evaluate the efficiency and effectiveness of the maintenance area, it is essential to carry out an audit that detects and diagnoses the problems that could develop, provides solutions to these dysfunctions and adapts the function of maintenance to the specifications of the standard ISO 9001.

A maintenance audit is applied to a service company. The methodology applied to design the audit is based on the integration of the weighting technique Simple Multiple Attribute Rating Technique (SMART), the value analysis technique (applied generally to new product design) and an expert system based on rules. The SMART technique provides the weighting between the functions related to sections of the bank entity and through value analysis the limit values for states of functions for each section and the current value for functions of the bank entity can be obtained. By means of decision rules the previous values are interconnected using different first and second level variables to establish the state of the maintenance activities by sections.

The expert system simulates the behaviour of a human expert specializing in the area, by means of numerous rules and relations between different variables associated with the specific maintenance functions, in order to obtain the maintenance state by sections and the general maintenance state of the bank.

The development of a maintenance audit in a service company, where the number of contributions is very limited, in comparison with manufacturing companies, is presented. Also presented is the integration of decision‐making tools such as the weighting technique SMART with the value analysis technique and rule‐based expert system to create a maintenance audit. The maintenance audit developed can be applied in the context of a continuous improvement environment.

The main purpose is to provide a demonstration of the utility of the DMG as a streamlined approach of a prescriptive-type model that can facilitate strategic and dynamic methodology to the decision-maker with respect to what policies, strategies or actions should be carried out.

This paper proposes a framework for an agile criticality assessment process using decision-making grid (DMG) to accommodate the needs of this dynamic environment.

The proposed new approach has delivered better results with more consistency when applied by different teams and achieved better distribution of assets over the criticality scale.

The proposed approach has been validated through an industrial case study related to a steam generation system (SGS).

The implementation of the proposed approach in a petroleum refinery to assess the criticality of steam generation system (SGS) has shown positive results in terms of time and effort optimization. This research contributes to production planning and control literature with respect to one of its core activities of maintenance, through an innovative, systematic and practical approach.