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The purpose of this paper is to develop a stochastic detailed schedule for a preventive/scheduled/periodic maintenance program of a military aircraft, specifically a rotorcraft or helicopter.

The new model, entitled the military “periodic aviation maintenance stochastic schedule” (PAM-SS), develops a stochastic detailed schedule for a PUMA SA 330SM helicopter for the 50-h periodic inspection, using cyclic operation network (CYCLONE) and Monte Carlo simulation (MCS) techniques. The PAM-SS model identifies the different periodic inspection tasks of the maintenance schedule, allocates the resources required for each task, evaluates a stochastic duration of each inspection task, evaluates the probability of occurrence for each breakdown or repair, develops the CYCLONE model of the stochastic schedule and simulates the model using MCS.

The 50-h maintenance stochastic duration follows a normal probability distribution and has a mean value of 323 min and a standard deviation of 23.7 min. Also, the stochastic maintenance schedule lies between 299 and 306 min for a 99 per cent confidence level. Furthermore, except the pilot and the electrical team (approximately 90 per cent idle), all other teams are around 40 per cent idle. A sensitivity analysis is also performed and yielded that the PAM-SS model is not sensitive to the number of technicians in each team; however, it is highly sensitive to the probability of occurrence of the breakdowns/repairs.

The PAM-SS model is specifically developed for military rotorcrafts, to manage the different resources involved in the detailed planning and scheduling of the periodic/scheduled maintenance, mainly the 50-h inspection. It evaluates the resources utilization (idleness and queue), the stochastic maintenance duration and identifies backlogs and bottlenecks.

The PAM-SS tackles military aircraft planning and scheduling in a stochastic methodology, considering uncertainties in all inspection task durations and breakdown or repair durations. The PAM-SS, although developed for rotorcrafts can be further developed for any other type of military aircraft or any other scheduled maintenance program interval.

Productivity, based on estimated and actual hours, of most maintenance workers is only 30 to 50 per cent. Given the significance of maintenance to manufacturing competitiveness, it is surprising how little research is being carried out. Scheduling is a crucial component of maintenance management and is a focus of research. Identifies the areas of concern in maintenance scheduling and surveys representative work from the academic and practitioner literature. Specific points of practice and theory which need further investigation are pinpointed.

Addresses the problem of maintenance planning and scheduling and reviews pertinent literature. Discusses the characteristics and the complexity of the problem. Advocates mathematical programming approaches for addressing the maintenance scheduling problem. Gives examples to demonstrate the utility of these approaches. Proposes expansion of the state‐of‐the‐art maintenance management information system to utilize the mathematical programming approaches and to have better control over the maintenance scheduling problem.

The purpose of this paper is to describe an integer linear programming model to schedule the maintenance crew and the maintenance tasks in a bus operating company.

The proposed methodology relies on an integer linear programming model that finds feasible maintenance schedules. It minimizes the costs associated with maintenance crew and the costs associated with unavailability. The model is applied in a real-world case study of a Portuguese bus operating company. A constructive heuristic approach is put forward, based on solving the maintenance scheduling problem for each bus separately.

The heuristic finds better solutions than the exact methods (based on branch-and-bound techniques) in a much lower computational time.

The results suggest the relevance of such heuristic approaches for maintenance scheduling in practice.

This proposed model is an effective decision-making support method that provides feasible maintenance schedules for the maintenance technicians and for the maintenance tasks in a fleet of buses. It also complies with several operational, technical and labour constraints.

The purpose of this paper is to explore the possibilities of improving the quality of existing maintenance task of the atomizer of milk powder manufacturing unit of a dairy plant. Looking to the past business volume and expected growth, the milk powder manufacturing unit forms a noticeable sector of processing plant. The lack of quality in maintenance standards leads to reliability losses of about 20–25% with low productivity and profit. Such facts and challenges of keeping the system in ready-state motivate a definite maintenance plan to be modeled based on a live failure analysis to be executed during shutdown or scheduled period.

The deliverables are achieved by collecting the historical failure data i.e. downtime and failure frequencies; from January 2020 to July 2020 at Dudhsagar dairy, Gujarat, India. Reliability modeling is done in a view to understand the failure pattern behavior of the milk powder manufacturing unit. The atomizer is discriminated as a critical component based on these data and their functional failures, failure causes, effects and repercussions of failures with existing control and maintenance practices has been modeled based on live shop-floor study. Scores are assigned on 1 to 10 levels by analyzing attributes effects from lowest to highest concern respectively for every modes of failure through realistic brain-storming among maintenance team by incorporating some advanced attributes like maintainability, economic safety, economic cost and spares with basic criteria in this study. The maintainability criticality index (MCI) is narrated by these score values through multi-attribute decision-making (MADM) based failure analysis models like Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS).

The primary findings of this research work are to propose improvements in the quality of the maintenance plan of critical component like; atomizer of a milk powder manufacturing unit which is commonly representing critical component in a major range of industrial processes. The case study recommended four silent maintenance strategies i.e. scheduled maintenance scheduled discard, scheduled failure finding and redesign as a qualified maintenance plan for the atomizer based on MCI and rankings of its potential failure causes. The results are helpful in upgrading quality standards for the maintenance activities of a process industry of alike or of dissimilar kinds in accordance with the failure analysis.

Originality mainly consists of investigating the scope of enhancing the existing maintenance practices through actual failure analysis with the help of TOPSIS. The criteria employed in this study are probability of chances of failure, degree of detectability and degree of severity as basic criteria along with some advanced criteria like; maintainability, spare parts, economic cost, economic safety are selected based on the outcome of shop-floor study and reliability modeling. The notable past failure statistics (downtime, frequency of failures) of a milk powder manufacturing unit were recorded and these data are analyzed based on reliability to extract an explicative component i.e. atomizer.

This paper documents research and development that were undertaken as collaboration between the Industrial Research Institute of Swinburne University of Technology (IRIS), Armor Pty Ltd and QANTAS. The objective of the research was to investigate the application of a unitary software structure, composed of the critical path method (CPM), materials requirements planning (MRP) and production activity control (PAC) techniques, to the management of large‐scale maintenance activities (specifically aircraft maintenance). This structure had previously been applied to the manufacturing (i.e. assembly) process but the maintenance problem posed significant new challenges. First, there was the issue of generating a disassembly structure, and second, the reconciliation of demands arising from non‐serviceable components. This paper documents the implementation of the structure and the methods that were used to validate its functionality on a test‐case application (i.e. aircraft maintenance problem).

The modern helicopters are designed with maximum serviceability and long life expectancy to ensure minimum life cycle cost. The purpose of this paper is to present a framework to incorporate the customer requirements on reliability and maintainability (R&M) parameters into the design and development phase of a contemporary helicopter, and to discuss the way to capture operational data to establish and improve the R&M parameters to reduce life cycle cost.

From the analysis, it is established that the reliability and maintainability cost is the major contributor to the life cost. The significant reliability and maintainability parameters which influence R&M cost are identified from analysis. The operational and design data of a contemporary helicopter are collected, compiled and analyzed to establish and improve the reliability and maintainability parameters.

The process depicted in the paper is followed for a contemporary helicopter and substantial amount of life cycle cost reduction is observed with improvement of R&M parameters.

The benefits of this methodology not only reduce life cycle cost but also improve the availability/serviceability through less failure and less time for scheduled maintenance. The methodologies also provide the reliability trends indicating potential area for design improvement.

The proposed approach assists asset managers to reduce the life cycle costs through improvement of R&M parameters.

This paper reviews the basic concepts of several maintenance approaches and discusses the increasing needs of effectiveness‐centred maintenance (ECM). It discusses the principles and relates them to the measurement of ECM performance. The development and implementation of the ECM approach is elaborated based on a pilot program in the radio unit of an electricity company in Hong Kong. Two ECM performance indices (i.e. individual system effectiveness (ISE) and overall system effectiveness (OSE)) were introduced to monitor the ECM process in the company. Being an integrated maintenance approach, ECM focuses on system functions and customer service, and may contribute to the continuous improvement of maintenance management practices in organizations irrespective of their business nature and size.

High-maintenance cost is the common issue in building industry due to low service quality of maintenance management in Malaysia. Lack of preventive measure is the problem that implicates poor maintenance performance. Scheduled maintenance is suggested to improve the maintenance performance. However, the effectiveness of scheduled maintenance can be greatly influenced by the availability of skilled technicians. Thus, the purpose of this paper is to identify the aspects of skilled technician to be concerned in maintenance management, as well as to establish the relationship between the aspects and maintenance cost performance.

A quantitative approach is adopted and carried out through questionnaire survey. Furthermore, descriptive analysis and correlation analysis are used to analyse the research data.

The literature review identifies three aspects of skilled technician to be concerned in maintenance management. Then, research result demonstrates that the skill and knowledge of technician is significantly correlated to the maintenance cost variance. The skill and knowledge of technician must be considered in maintenance planning and execution.

The research recommends the maintenance management to employ skilled technician through thorough hiring process and to encourage the existing maintenance staff for participating the relevant training, workshop, or seminar.

The purpose of this paper is to solve the maintenance management problems of generating units under the reliability criterion.

The problem has been formulated as a combinatorial optimization task, with explicit and simultaneous treatment of multiple objectives: maximization of reliability, minimization of fuel costs and minimization of constraint violations. This paper formulates a general generator maintenance management (GMM) problem using a reliability criterion and a novel bio‐inspired search technique, namely, artificial bee colony (ABC) algorithm is applied to determine the optimal generator maintenance schedule.

A novel meta‐heuristic search technique based algorithm has been developed to determine the optimal maintenance schedule of generating units to improve the system reliability.

The contribution of the paper is that an efficient bio‐inspired algorithm based solution technique has been developed to solve a very important problem for a power utility, i.e. the economical and reliable operation of a power system.