Prioritization of maintenance actions in water distribution systems

[EN] Industrial water distribution systems are paramount in many manufacturing systems to optimise the related industrial plant availability and consequently the level of production. They also play an important part in keeping right standards of hygiene of workplaces and machines. A strategic action of planning and implementing of suitable maintenance activities is necessary to assure the standards previously described. The present contribution proposes the prioritization of maintenance actions for industrial water distribution systems through a multi-criteria decision making approach, since some of the elements integrated in maintenance-related aspects are not easily quantifiable and, on t…

Flexible negotiation process to adhere to human preferences; A case of work equipment risk assessment

Making structured and reliable decisions on relevant business problems often requires expert assistance. In decision making practice, experts are frequently required to pairwise compare elements to support the decision made. This paper proposes a user-friendly negotiation procedure to establish an effective feedback relation with experts to globally increase the consistency of their pairwise comparisons judgments, where necessary. To this aim, we develop a flexible tool, which makes use of an algebraic consistency-improving algorithm and a sensitivity analysis technique to identify which judgments contribute most to inconsistency. The framework pursues friendliness for the involved decision…

A multi criteria decision making approach to support the risk management: a case study

Project risk management plays a fundamental role in the project management field. Project objectives may dynamically change in time, hence it is not easy to satisfy them, especially when related to complex projects. In detail, they can be subjected to several and different risk conditions which have an important impact on the project success. In this context, multi-criteria decision making (MCDM) methods are effective tools to carry out the risk management. In particular, the present research proposes the use of MCDM with a specific focus on the ELECTRE TRI method. The last one is able to evaluate and assign projects under analysis into ordered and different risk classes. The purpose consis…

Maintenance Planning For The Reliability Maximization In A Large System With Vagueness In The Reliability Values Of Some Components

This paper tackles the problem to single out the maintenance actions to be executed on a production system during the planned stop of given length. In detail, from a reliability viewpoint the system is assimilated as a series-parallel multi-component system and the maintenance actions need to maximize the system reliability up to the next planned stop. Moreover, it is assumed that some components reliability values are affected by vagueness within a given range. To solve the considered problem, an exact dynamic programming algorithm suitable to quickly point out the maintenance scheduling is developed and, moreover, it is formulated a proper parameter able to express the robustness of the o…

Some consistency issues in multi-criteria decision making

The complexity of decision-making problems included under the multi-criteria decision-making (MCDM) paradigm has favored the proliferation of many schools of thought and varied methodologies. It has not yet been possible to prove the supremacy of any of these approaches. Moreover, in some cases it is difficult to combine the theoretical validity of the approximations with their practical appropriateness. It seems that rigor and applicability are two opposing concepts, something that should not be so. It is our responsibility to bridge the gap. To reduce the gap between theory and practice and use effective methodological approaches, it is necessary to combine the rigor and objectivity of tr…

Improving the logistic process of orders dispatching through a multi-criteria decision-making perspective

International audience; Far from being a mere production-oriented mission, competition among companies has to be considered as a much wider concept, largely based on effective supply chain management. Implementing suitable supply chain strategies is indeed crucial for enterprises seeking to strengthen their own position in the market against their competitors. With this recognition, one of the main issue in the logistic field is the suppliers and orders management, that is a complex decision-making problem depending on a wide set of aspects mutually correlated and often conflicting each other. This is the reason why assuming a Multi-Criteria Decision-Making (MCDM) perspective is useful to d…

Combined HACCP and TOPSIS-based approach to prioritize risks in the salmon manufacturing process: A case study

The food safety risk assessment is defined by the Codex Alimentarius Commission as the scientific evaluation of known or potential adverse health effects resulting from human exposure to food-borne hazards. Nowadays, the implementation of a systematic and disciplined risk assessment approach in the food safety field is recognized to be a powerful tool for carrying out science-based analyses and for reaching sound consistent solutions to food safety problems. With this recognition, a combined Hazard Analysis and Critical Control Point (HACCP) and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS)-based approach is proposed in the present paper to prioritize risks of t…

The ELECTRE I method to optimise GPR data processing analyses for maintenance of water networks

Management of water supply systems (WSSs) can be effectively pursued by means of data processing techniques based on Ground Penetrating Radar (GPR) image mining. This approach enables to collect different graphical representations of WSS buried elements on the basis of which planning maintenance interventions, with the objective of improving the overall condition of the system. This paper proposes to support this kind of techniques by means of a multi criteria decision making (MCDM) point of view. In particular, the ELECTRE I method is suggested to treat results coming from the application of different techniques. A real case study is applied with relation to a set of four alternatives, whi…

ELECTRE TRI to classify items with respect to maintainability criterion

The paper aims to suggest a methodology able to support the analyst in the assessment process of items on the base of a criterion inspired to the maintainability parameter and in the successive assignment phase of the items in the predefined classes. The maintainability involves the continuous improvement of a system in order to improve the ability to maintain or improve the reliability of the analyzed system. In particular, the last one is the probability that a failed system will be restored to specified conditions within a given period of time when maintenance is performed according to prescribed procedures and resources. The faced case in this research regards the software maintenance, …

An efficient proposal for the application of simulated annealing algorithms

Complex nonlinear optimization problems require specific resolution techniques. These problems are often characterized by a solution space that presents many local optima. In these cases, local search algorithms, as the classical descent neighborhood search method, have a heavy drawback: the optimization algorithm generally converges towards a local minimum. To avoid getting trapped in a local minimum, the optimization algorithm must allow to accept worse solutions than the current one. Several kinds of algorithms have been ideated for this purpose and they differ for the acceptance criteria of a pejorative solution. Among such algorithms it is possible to remember the Taboo Search (TS) and…

Ranking of shelf life models based on smart logistic unit using the ELECTRE III method

The aim of this paper is the evaluation of Shelf Life (SL) models based on Smart logistic unit to support the management of the food supply chain in order to guarantee the shelf life of products in agreement with logistic efficiency and system sustainability. For this purpose, the main shelf life equations based on parameters that influence the quality of perishable products were defined and the correspondent acquiring and gathered system has been developed. The selection of the optimal SL model was carried out by means of the multi-criteria decision-making procedure ELECTRE III.

The FTOPSIS method to support FMECA analyses

This paper proposes an approach based on multi-criteria decisional methods to manage the results derived from reliability analyses. In detail, this paper proposes ranking the failure modes of a system when analyzed with failure modes, effects and criticality analysis (FMECA) using the technique for order preference by similarity to ideal solutions (TOPSIS). To better manage the uncertainty of evaluations made under the differing criteria, the TOPSIS method is applied in its fuzzy version (FTOPSIS). When the method is applied to a case study, the results highlight the main possible critical faults and supply fundamental information to take into account during the scheduling of maintenance ac…

A fuzzy parameter to characterize the uncertainty in the plant layout design

The present work aims at proposing a methodology able to return a single parameter that synthesizes the aspects characterizing the layout design problem that the analyst translates into requests of closeness and distance among departments. In order to consider the uncertainty of the problem, closeness and distance requests are expressed by means of fuzzy numbers and a weight fuzzy function modules the importance of the aspects by allowing the analyst to express his/her priorities on the basis of the specific decisional context. The weight function is characterized by the presence of a threshold value that makes the method non compensative. The hypothesis herein assumed is that, when the dis…

Human reliability analysis to support the development of a software project

The Human Reliability Analysis (HRA) is considered as a useful tool in predicting and quantifying the occurrence of human errors during the execution of a specific task. With this recognition, the present paper firstly aims at discussing the support given by HRA methodologies to the fault risk evaluation. Then, the Technique for Human Error Rate Prediction (THERP) is suggested to evaluate the success probability of a software development project.

k-out-of-n systems: an exact formula for the stationary availability and multi-objective configuration design based on mathematical programming and TOPSIS

[EN] Reliability and availability analyses are recognized as essential for guiding decision makers in the implementation of actions addressed to improve the technical and economical performance of complex systems. For industrial systems with reparable components, the most interesting parameter used to drive maintenance is the stationary availability. In this regard, the present paper proposes an exact formula for computing the system stationary availability of a k-out-of-n system. Such a formula is proved to be in agreement with the fundamental theorem of Markov chains. Then, a multi-objective mathematical model is formulated for choosing the optimal system configuration design. The Pareto …

Managerial decision making for complex service systems Optimization

The present paper deals with managerial decisions for Predictive Maintenance (PrdM) of complex service systems. We propose a Multi-Criteria Decision-Making (MCDM) approach aimed at sorting those failure modes potentially involving critical components into risk classes for interventions prioritisation and maintenance control. In this context, the sorting technique ELimination Et Choix Traduisant la REalité (ELECTRE) TRI is applied to support in finding the root causes that can be eliminated for failure prevention and/or minimization. This methodology presents the advantage to not rely on comparisons (as well as on their transitivity) between pairs of elements, simplifying computations for co…

A Multi-Criteria Group Decision To Support The Maintenance Service: A Case Study

The present paper wants to propose a methodology to support a group of decision makers into the choice of actions, to implement on a multi-component system, regarding the maintenance service. The choice has to be made on the basis of several criteria, namely the total maintenance cost, the system unavailability and by considering the maintenance actions feasibility. In particular, with the aim to select the maintenance service that represents for the group the best comprise among the criteria to satisfy, the proposed methodology consists of two multi-criteria decisions methods to apply in two successive phases. The first one regards the application of the Analytic Hierarchy Process (AHP) to…

An effective approach for the maintenance scheduling in large systems with required reliability level: A case study

This paper deals with the problem of the maintenance scheduling in a multi-component system for which a required reliability level has to be warranted until the next planned stop for maintenance. Particularly, the tackled problem concerns both the determination of the elements set on which to perform preventive maintenance and the optimal number of maintenance crews in order to warranty the required reliability level at the minimum maintenance cost. The problem is formulated as a mathematical programming model that becomes very hard to solve for large practical systems. For such reason, a new effective approach based on a constrained genetic algorithm is herein proposed and tested with refe…

A multi-decision makers approach to select the maintenance plan for a multi-component system.

DEMATEL-based consensual selection of suitable maintenance KPIs

This paper aims to highlight the fundamental role of Multi-Criteria Decision-Making (MCDM) tools to perform efficiently in such a complex field as industrial maintenance. Typically, a strategic plan of maintenance interventions has to be first implemented and then continuously checked by maintenance management. Given the importance to monitor the quality and suitability of the undertaken choices, the Decision-Making Trial and Evaluation Laboratory (DEMATEL) method is herein suggested to evaluate some of the most important maintenance Key Performance Indicators (KPIs) on the basis of their mutual relationships. DEMATEL is particularly adequate to take into account interdependencies existing …