A Group Decision Making Approach for Dealing with Fuzziness in Decision Process

In order to deal with various imprecise opinions and preferences of decision makers in group decision-making process, this paper proposes a fuzzy group decision-making approach. The approach has three advantages from existing approaches. First, it can handle simultaneously group members’ fuzzy preferences for alternative solutions, fuzzy judgments for solution selection criteria and fuzzy weights for their roles in group decision-making to arrive a group consensus decision. Second, it allows group members to generate selection criteria for the best solution rather than assume them to be given before a group meeting. The third is that it uses general fuzzy number to express linguistic terms which is used to describe the fuzziness of individual preferences, judgments and weights in group decision-making. It therefore accepts any forms of fuzzy number, including triangular fuzzy number, rectangle fuzzy number and continuous fuzzy number, when applying the group decision-making approach

VALIDATION OF A SUPPORT SYSTEM ON BUILDING SYSTEM SELECTION IN CONSTRUCTION

Decisions for multi-person on building system selection are very complicated since many parties involved. Where a number of stakeholders are involved in choosing single alternative from a set of alternatives, there are different concern caused by differing preferences, experiences, and background. Therefore, a support system is required to enable each stakeholder to evaluate and rank the solution alternatives before engaging into negotiation. This paper presents a validation process of the negotiation support system in building system selection. A case study was carried out in a real estate company in Indonesia. Validation was conducted to a framework of coalition formation as a basis algorithm of negotiation support for building system selection in construction. Two methods of validation were conducted in a group decision to select building roof system. These methods are decision result validation by similarity index and stakeholder preferences validation by canonical correlation analysis and a set of descriptive statistic analysis. Two others conventional model were compared with the coalition formation algorithms. This validation process reveals that the algorithms proposed is better than single weight factor and aggregation method in terms of closely to the best fit option, stakeholder satisfaction, and performance of the model

Consensus in a fuzzy environment: a bibliometric study

In today’s organizations, group decision making has become a part of everyday organizational life. It involves multiple individuals interacting to reach a decision. An important question here is the level of agreement or consensus achieved among the individuals before making the decision. Traditionally, consensus has been meant to be a full and unanimous agreement. However, it is often not reachable in practice. A more reasonable approach is the use of softer consensus measures, which assess the consensus in a more flexible way, reflecting the large spectrum of possible partial agreements and guiding the discussion process until widespread agreement is achieved. As soft consensus measures are more human-consistent in the sense that they better reflect a real human perception of the essence of consensus, consensus models based on these kind of measures have been widely proposed. The aim of this contribution is to present a bibliometric study performed on the consensus approaches that have been proposed in a fuzzy environment. It gives an overview about the research products gathered in this research field. To do so, several points have been studied, among others: countries, journals, top contributing authors, most cited keywords, papers and authors. This allows us to show a quick shot of the state of the art in this research area

A fuzzy logic based method to monitor organizational resilience: application in a brazilian radioactive facility

Resilience is the intrinsic ability of a system to adjust its functioning prior to, during, or following changes and disturbances, so that it can sustain required operations under expected and unexpected conditions. This definition focuses on the ability to function, rather than on being impervious to failure, and thereby overcomes the traditional conflict between productivity and safety. Resilience engineering (RE) has fast become ecognized as a valuable complement to the established approaches to safety of complex socio-technical systems and methods to monitor organizational resilience are needed. However, few, if any, comprehensive and systematic research studies focus on developing an objective, reliable and practical assessment model for monitoring organizational resilience. Most methods cannot fully solve the subjectivity of resilience evaluation. In order to remedy this deficiency, the aim of this research is to adopt a Fuzzy Set Theory (FST) approach to establish a method for resilience assessment in organizations based on leading safety performance indicators, defined according to the resilience engineering principles. The method uses FST concepts and properties to model the indicators and to assess the results of their application. To exemplify the method we performed an exploratory case study at the process of radiopharmaceuticals dispatch package of a Brazilian radioactive facility

A fuzzy method for the usability evaluation of nuclear medical equipment

To avoid errors when handling nuclear medical equipment, it is important to develop products with a high degree of usability. This can be achieved by performing usability evaluations in the product development process to detect and mitigate potential usability problems. Usability evaluation focuses on how well users can learn and use a product to achieve their goals. Thus, the usability evaluation has become recognized as a valuable complement to the established approaches to design good user interfaces, to reduce incidents and accidents as well the time required to learn how to use the equipment. To gather information about usability, practitioners use a variety of methods that gather feedback from users about an existing interface or plans related to a new interface. A wide range of usability evaluation methods have been proposed, but few methods focus on developing an objective and practical evaluation method for usability. Moreover, the usability evaluations are based on human judgments and most methods cannot fully solve the subjectivity of these evaluations. In order to remedy this deficiency, the purpose of this work is to adopt a Fuzzy Set Theory (FST) approach to establish a method for the usability evaluation of nuclear medical equipment based on usability heuristics for user interface design and international standards for ergonomics of human-system interaction. To exemplify the method we performed a usability evaluating of the Digital Spectrometer ESP 13004 by testing it with representative users. The results showed that the method is a proactive tool to provide a basis for checking usability of medical device interfaces

Résolution des problèmes de décision de groupe par analyse bipolaire

On entend par décision de groupe ici, la sélection par plusieurs décideurs, d’une ou plusieurs alternatives dans un ensemble vaste d’alternatives. Du fait de l’existence de plusieurs acteurs, le processus de décision doit tenir compte des relations d’influence (positive ou négative) qui peuvent exister entre les acteurs de la décision. De même, l’évaluation des alternatives par rapport aux objectifs des décideurs doit se faire en considérant plusieurs critères ou attributs caractérisant ces alternatives positivement ou négativement. Cette dualité, que ce soit au niveau des relations entre décideurs ou au niveau des relations entre attributs caractérisant les alternatives et les objectifs, est prise en compte dans ce papier à travers la notion de bipolarité. Ainsi, les relations entre décideurs seront évaluées à travers des mesures de concordance et de discordance et les relations entre attributs et objectifs à travers les notions de supportabilité et de rejetabilité. Au final, pour chaque décideur une alternative sera évaluée, par deux mesures ; une mesure de sélectabilité qui agrège les aspects positifs de l’alternative et une mesure de rejetabilité qui agrège les aspects négatifs dans le formalisme des jeux satisfaisants. Un processus de recherche de consensus entre décideurs est proposé pour aboutir à une solution finale dans le cas où aucune alternative ne satisfait simultanément tous les décideurs

Um método proativo para gerenciamento da segurança em instalações nucleares

Em razão da abordagem moderna para tratar a segurança em instalações nucleares que destaca que estas organizações devem ser capazes de avaliar e gerenciar de forma proativa suas atividades torna-se cada vez mais importante a necessidade de instrumentos de avaliação das condições de trabalho. Nesse contexto, este trabalho apresenta um método proativo de gerenciamento da segurança organizacional, o qual apresenta três características inovadoras: 1) a utilização de indicadores preditivos que fornecem informações atuais sobre o desempenho das atividades, permitindo ações preventivas e não somente reativas na gestão da segurança, diferente dos indicadores de segurança tradicionalmente utilizados (indicadores reativos) que são obtidos após a ocorrência de eventos indesejados; 2) a adoção do enfoque da engenharia de resiliência no desenvolvimento dos indicadores – os indicadores são baseados em seis princípios da engenharia de resiliência: comprometimento da alta direção, aprendizagem, flexibilidade, consciência, cultura de justiça e preparação para os problemas; 3) a adoção dos conceitos e propriedades da teoria dos conjuntos fuzzy para lidar com a subjetividade e a consistência dos julgamentos humanos na avaliação dos indicadores. A teoria fuzzy é usada essencialmente para mapear modelos qualitativos de tomada de decisão, e para métodos de representação imprecisa. Os resultados deste trabalho objetivam uma melhoria no desempenho e na segurança nas organizações. O método foi aplicado no setor de expedição de radiofármacos de uma instalação nuclear. Os resultados mostraram que o método é uma boa ferramenta de monitoramento de forma objetiva e proativa das condições de trabalho de um domínio organizacional

Zoning Mashhad Watershed for Artificial Recharge of Underground Aquifers using TOPSIS Model and GIS Technique

In recent years coincide with population growth and industrial expansion in many countries in the world Extract water of underground sources expanded and annual withdrawal of ground water is higher than the annual feeding This means extracting and using the water in layers that has been saved over thousands of years in the underground Consequently groundwater levels in the area will be extracted every day and eventually drop where the water will not exist While proper management and control of these resources will eliminate the problems of drop in water level One way to managing groundwater resources is artificial recharge of groundwater and determine suitable locations for these purpose growth and development trend of Mashhad city and excessive Extracting of ground water in recent years has been essential groundwater resources management strategy in the region more than ever implied The purpose of this study is Zoning Mashhad watershed for artificial recharge of underground aquifers using TOPSIS Model and GIS technique TOPSIS algorithm is a Multi Criteria Decision Making a type of compensatory model and an adaptable subgroup with strong ability to solve multi alternative problems because of having ability to overlap indicators in weak and power points In this model if quantitative criteria can change in to qualitative criteria qualitative criteria can be used besides quantitative criteria In aforementioned model it is supposed that each indicator and criterion has steady increasing and decreasing utility in decision making matrix it means if criteria gain more positive amount they will be more appropriate on the contrary the more negative amount the less appropriate The result and findings of different studies show that in TOPSIS method zone 3 with 0 669 point promotes in first rank among 5 studied zones and thus it is the most appropriate zone to establish the proper area for artificial recharge of underground aquifers in contrast zone

Hybrid Method For Forecasting A Steel Mill's Sales

This paper presents a proposal of long range steel mill's sales forecasting method. It can be also used in other sectors of steel industry, and (after minor modifications) in enterprises operating in a power industry, building materials industry, plastics industry etc. Heuristic methods are often used in long range forecasting. In the proposed method few parameters are predicted with fuzzy Delphi method. It results in the forecasts in form of fuzzy triangular numbers. Transformation of possibility distribution, generated by fuzzy number, into a probability distribution enables to integrate forecasts obtained from fuzzy Delphi method with those prepared with structural models and developmental trends models. A computer simulation is used to determine sales forecast's expected value and probability distribution. In case of structural models and developmental trends models a simulation with re-estimation has been used. The method presented in this paper is used to generate random numbers from a set determined by triangular fuzzy number