A combined multi-criteria approach to support FMECA analyses: A real-world case

[EN] The paper proposes an approach that combines reliability analyses and multi-criteria decision methods to optimize maintenance activities of complex systems. A failure mode, effects, and criticality analysts (FMECA) is initially performed and the fuzzy TOPSIS (FTOPSIS) method is then applied to rank previously identified failure modes. For prioritization, failure modes are assessed against three evaluation criteria that differ from those traditionally involved in risk priority number (RPN) computation (i.e. severity, occurrence and detection). Two criteria refer to the maintenance management reflecting the operational time taken by the maintenance activity performed after the occurrence…

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 Feasible Framework for Maintenance Digitalization

The entire industry is changing as a result of new developments in digital technology, and maintenance management is a crucial procedure that may take advantage of the opportunities brought about by industrial digitalization. To support digital innovation in maintenance management, this study intends to meet the cutting-edge necessity of addressing a transformation strategy in industrial contexts. Setting up a customized pathway with adequate methodologies, digitalization tools, and collaboration between the several stakeholders involved in the maintenance environment is the first step in this process. The results of a previous conference contribution, which revealed important digitalizatio…

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…

Constrained consistency enforcement in AHP

Abstract Decision-making in the presence of intangible elements must be based on a robust, but subtle, balance between expert know-how and judgment consistency when eliciting that know-how. This balance is frequently achieved as a trade-off reached after a feedback process softens the tension frequently found between one force steadily pulling towards (full) consistency, and another force driven by expert feeling and opinion. The linearization method, developed by the authors in the framework of the analytic hierarchy process, is a pull-towards-consistency mechanism that shows the path from an inconsistent body of judgment elicited from an expert towards consistency, by suggesting optimal c…

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…

A decision support system to assure high-performance maintenance service

PurposeThis study aims to propose a decision support system (DSS) for maintenance management of a service system, namely, a street cleaning service vehicle. Referring to the information flow management, the blockchain technology is integrated in the proposed DSS to assure data transparency and security.Design/methodology/approachThe DSS is designed to efficiently handle the data acquired by the network of sensors installed on selected system components and to support the maintenance management. The DSS supports the decision makers to select a subset of indicators (KPIs) by means of the DEcision-MAaking Trial and Evaluation Laboratory method and to monitor the efficiency of performed prevent…

Optimal placement of quality sensors in water distribution systems

Water supply infrastructures are crucial for the sustainable existence and development of modern cities [1,2]. Water distribution systems (WDSs) are complex structures formed by many elements designed and erected to transport water of sufficient quality from water sources to consumers. The amount of the above elements, which can reach up to tens of thousands of links and junctions, their frequently wide spatial dispersion and the WDS characteristic of being very dynamic structures make the management of real WDSs a complex problem [3-5]. Moreover, although the main objective is to supply water in the quantity and quality required, other requirements are essential, namely maintaining conditi…

Consistent Clustering of Elements in Large Pairwise Comparison Matrices

[EN] In multi-attribute decision making the number of decision elements under consideration may be huge, especially for complex, real-world problems. Typically these elements are clustered and then the clusters organized hierarchically to reduce the number of elements to be simultaneously handled. These decomposition methodologies are intended to bring the problem within the cognitive ability of decision makers. However, such methodologies have disadvantages, and it may happen that such a priori clustering is not clear, and/or the problem has previously been addressed without any grouping action. This is the situation for the case study we address, in which a panel of experts gives opinions…

Assessing organizational risk in industry by evaluating interdependencies among human factors through the DEMATEL methodology

This contribution proposes a Multi-Criteria Decision-Making (MCDM)-based approach to support organizational risk assessment in industrial environments

Managing Human Factors to Reduce Organisational Risk in Industry

[EN] Human factors are intrinsically involved at virtually any level of most industrial/business activities, and may be responsible for several accidents and incidents, if not correctly identified and managed. Focusing on the significance of human behaviour in industry, this article proposes a multi-criteria decision-making (MCDM)-based approach to support organizational risk assessment in industrial environments. The decision-making trial and evaluation laboratory (DEMATEL) method is proposed as a mathematical framework to evaluate mutual relationships within a set of human factors involved in industrial processes, with the aim of highlighting priorities of intervention. A case study relat…

Characterization of the consistent completion of analytic hierarchy process comparison matrices using graph theory

Assessing supply chain risks in the automotive industry through a modified MCDM-based FMECA

Supply chains are complex networks that receive assiduous attention in the literature. Like any complex network, a supply chain is subject to a wide variety of risks that can result in significant economic losses and negative impacts in terms of image and prestige for companies. In circumstances of aggressive competition among companies, effective management of supply chain risks (SCRs) is crucial, and is currently a very active field of research. Failure Mode, Effects and Criticality Analysis (FMECA) has been recently extended to SCR identification and prioritization, aiming at reducing potential losses caused by lack of risk control. This article has a twofold objective. First, SCR assess…

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…

Decision-Making Tools to Manage the Microbiology of Drinking Water Distribution Systems

[EN] This paper uses a two-fold multi-criteria decision-making (MCDM) approach applied for the first time to the field of microbial management of drinking water distribution systems (DWDS). Specifically, the decision-making trial and evaluation laboratory (DEMATEL) was applied removing the need for reliance on expert judgement, and analysed interdependencies among water quality parameters and microbiological characteristics of DWDS composed of different pipe materials. In addition, the fuzzy technique for order preference by similarity to ideal solution (FTOPSIS) ranked the most common bacteria identified during trials in a DWDS according to their relative abundance while managing vagueness…

A risk evaluation framework for the best maintenance strategy: the case of a marine salt manufacture firm

Highlights • This paper proposes a MCDM framework to support risk evaluation for maintenance activities. • The ANP is proposed to select the best maintenance strategy on the basis of real systems’ features. • The ELECTRE III is used to prioritise the main risks related to the interventions of the selected maintenance policy. • The proposed framework is applied to a core subsystem of a real-world marine salt manufacture firm.

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 …

Contingency plan selection under interdependent risks

Managing supply chain risks (SCRs) has become an increasingly strategic key factor over the last decade, aimed at pursuing and maintaining business success. These types of risks clearly pose an important challenge to managers nowadays, and evaluating uncertainty affecting business scenarios is crucial. Indeed, COVID-19 has been dangerously affecting supply chains of global manufacturers, and is indicated as a main trigger cause of supply chain disruptions for a huge number of enterprises. Major effects derived from epidemic outbreaks on supply chains should be further adequately investigated since enterprises have been adopting poor risk management plans [1] to face them. Many companies, fo…

Multi-Objective and Multi-Criteria Analysis for Optimal Pump Scheduling in Water Systems

This contribution focuses on the problem of optimal pump scheduling, a fundamental element in pursuing operation optimization of water distribution systems. A combined approach of multi-objective optimization and multi-criteria analysis is herein suggested to first find the Pareto front of non-dominated solutions and then to rank them based on a set of weighted criteria. The Non-Dominated Sorting Genetic Algorithm (NSGA-II) is proposed to solve the multi-objective problem, while the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) is used to achieve the final ranking.

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…

Fuzzy cognitive maps for knowledge-oriented human risk management in industry

This contribution proposes an integrated approach making use of Fuzzy Cognitive Maps (FCMs) to organise in a flexibleway human knowledge about decision-making (DM) problems of interest in industry. By modelling human reasoning, FCMs allow to represent real phenomena on the basis of spontaneous human brainstorming on relations between pairs of relevant DM elements. Because of its characteristics, the use of FCMs can be effective to model DM problems such as human risk management, particularly critical in the industrial business sector. After identifying human risks in the existing literature, FCMs will be used to define relations among risks, which will be later prioritised by means of a mod…

An equation to calculate the availability for the k-out-of-n system

Reliability and availability (R&A) analyses are primary phases in management of complex systems and play a fundamental role in products and services quality. Management of maintenance activities has to be based on optimisation to simultaneously improve the operative conditions of the system. Maintenance optimization can be effeectively pursued by the RCM (Reliability-centered maintenance) approach. The authors demonstrate the global improvement of R&A by applying the RCM to the results derived by the FMECA (Failure Modes Effects and Criticality Analysis). Many efforts have been made to improve traditional methodologies of analysis, mainly tending to reduce the imprecision on data related to…

Multi-criteria risk classification to enhance complex supply networks performance

[EN] Management of complex supply networks is a fundamental business topic today. Especially in the presence of many and diverse stakeholders, identifying and assessing those risks having a potential negative impact on the performance of supply processes is of utmost importance and, as a result, implementing focused risk management actions is a current lively field of research. The possibility of supporting Supply Chain Risks Management (SCRM) is herein explored from a Multi-Criteria Decision-Making (MCDM)-based perspective. The sorting method ELimination Et Choix Traduisant la REalite (ELECTRE) TRI is proposed as a structural procedure to classify Supply Chain Risks (SCRs) into proper risk…

An integrated methodological approach for optimising complex systems subjected to predictive maintenance

Abstract The present paper addresses the relevant topic of maintenance management, widely recognised as a fundamental issue involving complex engineering systems and leading companies towards the optimisation of their assets while pursuing cost efficiency. With this regard, our research aims to provide companies with a hybrid methodological approach based on Multi-Criteria Decision-Making (MCDM) capable to deal with the main failures potentially involving complex systems subjected to predictive maintenance. Such an approach is going to be integrated within the framework of traditional Failure Mode Effects and Criticality Analysis (FMECA), whose strengths and weaknesses are considered. In pa…

Multi-criteria decision methods to support the maintenance management of complex systems

[ES] Esta tesis doctoral propone el uso de métodos de toma de decisiones multi-criterio (MCDM, por sus iniciales en inglés) como herramienta estratégica para apoyar la gestión del mantenimiento de sistemas complejos. El desarrollo de esta tesis doctoral se enmarca dentro de un acuerdo de cotutela entre la Università degli Studi di Palermo (UNIPA) y la Universitat Politècnica de València (UPV), dentro de sus respectivos programas de doctorado en 'Ingeniería de Innovación Tecnológica' y 'Matemáticas'. Estos programas están estrechamente vinculados a través del tópico MCDM, ya que proporciona herramientas cruciales para gestionar el mantenimiento de sistemas complejos reales utilizando análisi…

Water quality sensor placement: a multi-objective and multi-criteria approach

[EN] To satisfy their main goal, namely providing quality water to consumers, water distribution networks (WDNs) need to be suitably monitored. Only well designed and reliable monitoring data enables WDN managers to make sound decisions on their systems. In this belief, water utilities worldwide have invested in monitoring and data acquisition systems. However, good monitoring needs optimal sensor placement and presents a multi-objective problem where cost and quality are conflicting objectives (among others). In this paper, we address the solution to this multi-objective problem by integrating quality simulations using EPANET-MSX, with two optimization techniques. First, multi-objective op…

Managing expert knowledge in water network expansion project implementation

[EN] The implementation of expansion projects of water networks supplying growing cities is deemed to be a complex decision-making problem involving both technical aspects and expert knowledge. Management and control processes must rely on experts in the field whose know-how must be coupled with techniques able to deal with the natural subjectivity that affects input evaluations. Given the presence of many decision-making elements, the choice of proper hydraulic technical parameters may be linked to the main aspects of analysis requiring formal expert evaluation. In this contribution, the simulation of hydraulic indicators is integrated with a multi-criteria approach able to eventually dete…

Multi-criteria analysis applied to multi-objective optimal pump scheduling in water systems

Abstract This work presents a multi-criteria-based approach to automatically select specific non-dominated solutions from a Pareto front previously obtained using multi-objective optimization to find optimal solutions for pump control in a water supply system. Optimal operation of pumps in these utilities is paramount to enable water companies to achieve energy efficiency in their systems. The Fuzzy Technique for Order of Preference by Similarity to Ideal Solution (FTOPSIS) is used to rank the Pareto solutions found by the non-dominated sorting genetic algorithm (NSGA-II) employed to solve the multi-objective problem. Various scenarios are evaluated under leakage uncertainty conditions, res…

Multi‐criteria decision‐making approach for modular enterprise resource planning sorting problems

[EN] Implementing Enterprise Resource Planning (ERP) systems is currently recognized as a best practice with wide associated possibilities of business improvement for companies. Integrating these kinds of systems with business processes in the most efficient way requires to endeavour as much as possible simplifications for final users, which can be pursued by optimizing crucial software characteristics. The present article proposes a novel Multi-Criteria Decision-Making (MCDM) approach to deal with such an issue. Specifically, the ELECTRE (ELimination Et Choix Traduisant la REalite) TRI technique is suggested to assign ERP modules into predefined and ordered categories according to maintain…

Feedback-Based Algorithm for Negotiating Human Preferences and Making Risk Assessment Decisions

Work equipment risk assessment is essential for guaranteeing health and safety of workers in industrial contexts.Many and varied hazards are involved in the use of equipment,which have to be periodically subject to thorough controls required by law. This research proposes a novel hybrid decision-making framework aimed at integrating flexible negotiation on human preferences. This goal will be achieved by establishing effective feedback exchanges with expert(s) familiarwith the field of risk and maintenance of work equipment. We extend a previous research that proposed a user-friendly negotiation procedure to increase consistency of judgments provided by experts about relevant risk factors. …

Optimal design of k-out-of-n systems

The present paper is aimed at finding the best compromise to design a system k-out-of-n reliability configuration by means of the formulation of a multi-objective mathematical model. The Pareto front, which is the set of non-dominated solutions, is determined by considering the stationary availability and the achievable profit as objectives to be simultaneously optimized. The Pareto front represents a useful tool for the analyst to make the choice related to the analyzed design problem. In addition, the knowledge of the Pareto front permits to consider different design scenarios.

A hybrid multi-criteria approach to GPR image mining applied to water supply system maintenance

[EN] Data processing techniques for Ground Penetrating Radar (GPR) image mining provide essential information to optimize maintenance management of Water Supply Systems (WSSs). These techniques aim to elaborate on radargrams in order to produce meaningful graphical representations of critical buried components of WSSs. These representations are helpful non-destructive evaluation tools to prevent possible failures in WSSs by keeping them adequately monitored. This paper proposes an integrated multi-criteria decision making (MCDM) approach to prioritize various data processing techniques by means of ranking their outputs, namely their resulting GPR image representations. The Fuzzy Analytic Hi…

The ELECTRE I method to support the FMECA

In traditional Failure Modes, Effects and Criticality Analysis (FMECA), risk priorities of failure modes are determined through the Risk Priority Number (RPN), which is a function of the three risk parameters Occurrence (O), Severity (S), and Detection (D). In the present paper, an alternative approach to RPN is proposed for the criticality assessment of system failure modes. Particularly, the Multi-Criteria Decision Making (MCDM) method ELECTRE I is proposed to select the most critical failure mode in the set of the failure modes charactering a complex system. The method has been applied to a case study previously proposed by Zammori and Gabrielli (2012).

Updating the OSPF routing protocol for communication networks by optimal decision-making over the k-shortest path algorithm

Internet routing protocols such as Routing Information Protocol (RIP) pre-compute all the shortest paths by Dijkstra's algorithm (shortest path first, SPF) based on the number of hops between one node and another. Every time any communication is intended, RIP looks-up for the optimal choice in a routing table. This is a high speed method in the decision-making process but not necessary fast for data traffic as it does not take into account any real-time measure of route congestion. Open Shortest Path First (OSPF) presents a dynamic version of this problem by computing the shortest paths taking into account network features such as bandwidth, delay and load. OSPF thereby maintains link-state…

Optimal Placement of Pressure Sensors Using Fuzzy DEMATEL-Based Sensor Influence

[EN] Nowadays, optimal sensor placement (OSP) for leakage detection in water distribution networks is a lively field of research, and a challenge for water utilities in terms of network control, management, and maintenance. How many sensors to install and where to install them are crucial decisions to make for those utilities to reach a trade-off between efficiency and economy. In this paper, we address the where-to-install-them part of the OSP through the following elements: nodes' sensitivity to leakage, uncertainty of information, and redundancy through conditional entropy maximisation. We evaluate relationships among candidate sensors in a network to get a picture of the mutual influenc…

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 …

Management of uncertain pairwise comparisons in AHP through probabilistic concepts

Abstract Fast and judicious decision-making is paramount for the success of many activities and processes. However, various degrees of difficulty may affect the achievement of effective and optimal solutions. Decisions should ideally meet the best trade-off among as many of the involved factors as possible, especially in the case of complex problems. Substantial cognitive and technical skills are indispensable, while not always sufficient, to carry out optimal evaluations. One of the most common causes of wrong decisions derives from uncertainty and vagueness in making forecasts or attributing judgments. The literature shows numerous efforts towards the optimization and modeling of uncertai…

District metered area design through multicriteria and multiobjective optimization

[EN] The design of district metered areas (DMA) in potable water supply systems is of paramount importance for water utilities to properly manage their systems. Concomitant to their main objective, namely, to deliver quality water to consumers, the benefits include leakage reduction and prompt reaction in cases of natural or malicious contamination events. Given the structure of a water distribution network (WDN), graph theory is the basis for DMA design, and clustering algorithms can be applied to perform the partitioning. However, such sectorization entails a number of network modifications (installing cut-off valves and metering and control devices) involving costs and operation changes,…

Funciones test para optimización mono-objetivo

Para resolver la mayor parte de problemas de optimización del mundo real son necesarias técnicas sofisticadas, tales como los algoritmos evolutivos, que no se basan en el Cálculo Infinitesimal y que, en consecuencia, nunca caben en los planes de estudios de los grados en ciencia e ingeniería. No obstante, el ingeniero tendrá que utilizar tales técnicas antes o después. Para poner a prueba la habilidad de tales técnicas de optimización se suelen utilizar problemas de benchmarking que exhiben algunas de las características de los problemas del mundo real. En este artículo enumeramos brevemente algunas de tales características y presentamos una colección de problemas de optimización mono-objet…