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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Développement d'une approche floue multicritères pour une planification intégrée couplant la gestion de la performance et du risque / Development of a fuzzy multi-criteria approach for managing performance and risk in integrated procurement–production planning

Khemiri, Rihab 27 November 2017 (has links)
Le présent travail s’intéresse à la prise en compte de l’incertitude et du risque pour l’optimisation de la planification de production au niveau tactique d’une entreprise multi-sites d’une chaîne logistique. La méthode proposée permet d’assurer une planification des opérations de production et d’approvisionnement tout en intégrant au sein de son processus décisionnel un mécanisme de gestion de risque, en présence de diverses sources d’incertitude et d’ambigüité. Pour cela, une «bibliothèque» de critères structurés en deux classes indépendantes : critères de performance et critères de risque a été proposée, dans laquelle le décideur peut sélectionner ceux qui sont en cohérence avec ses préférences et sa stratégie de planification. La méthode doit chercher le bon compromis entre les performances et les risques prédéfinis par le décideur. Pour cela, nous nous somme dirigés dans un premier temps sur le développement d’une approche d’aide à la décision multicritères floue couplant un modèle analytique et la méthode TOPSIS floue. Cette approche consiste à générer un éventail de plans réalisables, caractérisés par leur performance et leur résistance aux risques. Le décideur peut alors choisir le plan qui reflète le compromis le plus adapté à sa stratégie de décision. Une deuxième approche d’optimisation multi-objectifs floue a été proposée dans un deuxième temps pour faire face à des problèmes de planification de grande taille au sein des chaînes logistiques opérant dans un environnement dynamique et incertain. Cette approche combine la méthode TOPSIS Floue, la programmation multi-objectifs possibiliste et la méthode du Goal Programming. L’objectif est de déterminer un plan jugé de bon compromis vis-à- vis des préférences du décideur par rapport aux objectifs de performance et de résistance aux risques. L’instanciation des deux approches proposées sur un exemple numérique a montré leur applicabilité et leur efficacité pour faire face à des problèmes de planification des chaînes logistiques utilisant des données incertaines et des préférences subjectives. Les expérimentations des deux approches permettant de tirer un ensemble d’enseignements utiles. / The work reported in this dissertation deals with risk-oriented integrated procurement–production approaches for tactical planning in a multi-echelon supply chain network presenting various sources of uncertainty and ambiguity. The proposed method allows planning of production and supply operations while integrating a risk management mechanism into its decision-making process, in the presence of various sources of uncertainty and ambiguity. So, a library" of criteria structured into two independent classes: Performance-based and risk-based decision criteria were proposed, in which the decision-maker can select those that are consistent with his preferences and his planning strategy. The method must seek the right compromise between performance and risk predefined by the decision-maker. To reach this goal, we initially focused on the development of a fuzzy multi-criteria decision making approach coupling an analytical model and the fuzzy TOPSIS method. This approach generates a range of feasible plans, characterized by their performance and their resistance to risks. The decision-maker can then choose the plan that reflects the compromise that best suits its decision strategy. Afterwards, a fuzzy multi-objective optimization approach was proposed to deal with large-scale planning problems within supply chains operating in a dynamic and uncertain environment. This approach second combines the Fuzzy TOPSIS method, the possibilistic multi-objective programming and the Goal Programming method. The objective is to determine a plan that is judged to be a good compromise compared to the decision maker's preferences regarding the performance and risk objectives. The instantiation of the two proposed approaches on a numerical example has shown their applicability and tractability to deal with supply chain planning problems in the presence of uncertain data and subjective preferences. The experiments of the two approaches make it possible to draw a useful set of lessons. The experiments of the two approaches show a set of useful issues.
52

[en] EVALUATION OF IMPACTS RESULTING ENERGY EFFICIENCY IN THE PULP AND PAPER INDUSTRY USING MULTICRITERIA DECISION MODEL / [pt] AVALIAÇÃO DE IMPACTOS DECORRENTES DA EFICIENTIZAÇÃO ENERGÉTICA NA INDÚSTRIA DE PAPEL E CELULOSE UTILIZANDO MODELO DE DECISÃO MULTICRITÉRIO

JOSE DANIEL HERNANDEZ VASQUEZ 13 August 2018 (has links)
[pt] A tese de doutorado tem por objetivo avaliar os impactos decorrentes da implementação de estratégias de eficientizacão energética na indústria de papel e celulose. A motivação pela escolha do tema resultou da necessidade de obter ganhos de energia considerando aspectos que, usualmente, não são considerando em programas de eficiência de energética (i.e.: aspectos sociais, técnicos, econômicos e ambientais). A metodologia utilizada –Método Multicritério de Apoio à Decisão Fuzzy-AHP-TOPSIS– (i) permitiu selecionar as tecnologias de eficientização aplicáveis ao subsetor de papel e celulose e (ii) possibilitou avaliar a influência de cada critério e subcritério na hierarquização de alternativas de eficientização energética. Os resultados consolidados permitiram: (i) confirmar que mudanças tanto nos processos, quantos nas tecnologias transversais do subsetor de papel e celulose devem ser implementadas; (ii) identificar os principais critérios decorrentes da eficientização energética no âmbito social, técnico, econômico e ambiental. Como conclusão, a pesquisa avaliou a relevância de cada critério, sugerindo, inclui-los em programas brasileiros de eficiência energética. Assim, a pesquisa legitima a sua contribuição para o setor energético brasileiro, promovendo o desenvolvimento de novos estudos na área de eficiência energética. / [en] The goal of this work is to evaluate the impacts of the implementation of energy efficiency strategies in the pulp and paper industry. The motivation for choosing the theme resulted from the need to obtain energy gains considering aspects that, usually not considered in energy efficiency programs (i.e.: social, technical, economical and environmental aspects). The methodology used –Multicriteria Decision Making Method Fuzzy-AHP-TOPSIS – (i) allowed to select the efficiency technologies applicable to the pulp and paper sub-sector and (ii) made it possible to evaluate the influence of each criterion and sub-criterion in the hierarchy of alternatives of energy efficiency. The consolidated results allowed: (i) to confirm that changes in the processes and in the transversal technologies of the pulp and paper subsector must be implemented; (ii) identify the main criteria resulting from energy efficiency in social, technical, economic and environmental aspects. As a conclusion, this work evaluated the relevance of each criterion, suggesting that it be included in Brazilian energy efficiency programs. Thus, the research legitimizes its contribution to the Brazilian energy sector, promoting the development of new studies in the area of energy efficiency.
53

Optimisation de la gestion du service de maintenance biomédicale / Optimization of the biomedical maintenance service management

Ben Houria, Zeineb 21 November 2016 (has links)
Le milieu hospitalier est un monde à la fois sensible et complexe, sensible parce que la vie humaine est en jeu et complexe parce que les équipements médicaux augmentent en nombre et en complexité technique. Ainsi, afin de préserver le bon état de fonctionnement de ces équipements et à un niveau élevé de disponibilité, leur entretien est devenu l'une des préoccupations majeures des responsables de l’hôpital. L’objectif de cette thèse est de proposer, aux responsables de maintenance biomédicale dans les établissements de soins, des outils d’aide à la décision qui permettent une meilleure maitrise des coûts. Ceci en assurant la sécurité des patients et des utilisateurs et en maintenant des performances optimales de l’ensemble des équipements médicaux. Tout d’abord, une heuristique a été proposée pour le choix de l’internalisation ou de l’externalisation de la maintenance et pour la sélection du contrat adéquat. La sélection du contrat est basée sur un ensemble de critères tout en considérant la contrainte du budget disponible. Ensuite, afin d’améliorer la procédure proposée, nous avons proposé des outils d’aide à la décision multicritère pour le choix adéquat d’une stratégie de maintenance. Pour l’étude de la criticité des équipements médicaux et le choix de la maintenance, sept critères ont été étudiés en proposant un couplage de l’approche AHP « Analytical Hierarchy Process » à la technique TOPSIS « Technique for Order Performance by Similarity to Ideal Solution ». Comme les experts du service de maintenance présentaient une certaine incertitude dans leurs jugements, nous avons intégré l’évaluation linguistique floue dans l’étude de la criticité des équipements et dans la sélection de la stratégie de maintenance (Fuzzy AHP couplée avec Fuzzy TOPSIS). Un modèle mathématique MILP a été développé pour la définition des limites de la criticité afin de caractériser les trois stratégies de maintenance. Le bon choix de ces limites permet d’optimiser le coût de la maintenance en respectant le budget disponible. Enfin, un deuxième modèle mathématique MILP a été développé en se basant sur l’heuristique proposée. Ce modèle permet de sélectionner pour chaque équipement, la stratégie de maintenance, internaliser ou externaliser la maintenance et le type du contrat tout en considérant le budget disponible et la charge/capacité du service maintenance / The hospital is a world that is both sensitive and complex, sensitive because the human life is involved and complex because medical facilities are growing in number and in technical complexity. Then, the problem of the medical equipment maintenance in order to keep them in safe, reliable and with high level of availability has become a major preoccupation of the hospital. The objective of this thesis is to provide tools to help the biomedical maintenance service of the hospital to make decisions that allow a better control of costs, while ensuring patient and user safety and maintaining optimal performance of medical equipment. First, a heuristic has been proposed for the choice of internalization or outsourcing maintenance and for the selection of the appropriate contract. The selection of the contract is based on a set of criteria while considering the available budget constraint. Then, to improve the proposed procedure, we proposed multi-criteria decision-making tools to select the appropriate maintenance strategies. Seven criteria have been designed to study the criticality of medical equipment and the choice of maintenance by providing a coupling of the AHP approach "Analytical Hierarchy Process" with TOPSIS technique "Technique for Order Performance by Similarity to Ideal Solution." As the expert judgments of the maintenance department presented some uncertainty, we integrated the fuzzy language assessment of the criticality of the equipment and the selection of the maintenance strategy (Fuzzy AHP coupled with Fuzzy TOPSIS). A mixed integer linear programming model (MILP) was developed to define thresholds of criticality to characterize the three maintenance strategies. According to these thresholds, maintenance cost can be optimized within the available budget. Finally, a second mixed integer linear programming model (MILP) was developed based on the proposed heuristic. This model allows selecting for each equipment, the maintenance strategy, the internalization or the outsourcing of the maintenance and the type of contract while considering the available budget and the workload / capacity of the maintenance department
54

Využití metod vícekriteriálního hodnocení variant ve veřejném sektoru / Apply the methods of multicriterial decision making in the public sector

DUŠEK, Jan January 2008 (has links)
The main purpose of this thesis was the application of the multicriterial decision making options methods on specific decision situations in the public sector. The task was to present the most important methods and to show the possibility of their use in reality. From the methods requiring ordinal information I chose the Cook - Seiford method which can be utilized when the sources are limited. From the cardinal data requiring methods I chose the Weighted Sum Approach method and the AHP method (based on the calculation of values of the utility function), the TOPSIS method (based on the minimization of distance from the ideal option) and the ELECTRE I. method (based on the plotting of the preferential relation).
55

Développement d'une approche floue multicritère d'aide à la coordination des décideurs pour la résolution des problèmes de sélection dans les chaines logistiques / Multi-criteria group decision making approach for the selection problem

Igoulalene, Idris 02 December 2014 (has links)
Dans le cadre de cette thèse, notre objectif est de développer une approche multicritère d'aide à la coordination des décideurs pour la résolution des problèmes de sélection dans les chaines logistiques. En effet, nous considérons le cas où nous avons k décideurs/experts notés ST1,...,STk qui cherchent à classer un ensemble de m alternatives/choix notées A1,...,Am évaluées en termes de n critères conflictuels notés C1,..., Cn. L'ensemble des données manipulées est flou. Chaque décideur est amené à exprimer ses préférences pour chaque alternative par rapport à chaque critère à travers une matrice dite matrice des préférences. Notre approche comprend principalement deux phases, respectivement une phase de consensus qui consiste à trouver un accord global entre les décideurs et une phase de classement qui traite le problème de classement des différentes alternatives.Comme résultats, pour la première phase, nous avons adapté deux mécanismes de consensus, le premier est basé sur l'opérateur mathématique neat OWA et le second sur la mesure de possibilité. De même, nous avons développé un nouveau mécanisme de consensus basé sur la programmation par but goal programming. Pour la phase de classement, nous avons adapté dans un premier temps la méthode TOPSIS et dans un second, le modèle du goal programming avec des fonctions de satisfaction. Pour illustrer l'applicabilité de notre approche, nous avons utilisé différents problèmes de sélection dans les chaines logistiques comme la sélection des systèmes de formation, la sélection des fournisseurs, la sélection des robots et la sélection des entrepôts. / This thesis presents a development of a multi-criteria group decision making approach to solve the selection problems in supply chains. Indeed, we start in the context where a group of k decision makers/experts, is in charge of the evaluation and the ranking of a set of potential m alternatives. The alternatives are evaluated in fuzzy environment while taking into consideration both subjective (qualitative) and objective (quantitative) n conflicting criteria. Each decision maker is brought to express his preferences for each alternative relative to each criterion through a fuzzy matrix called preference matrix. We have developed three new approaches for manufacturing strategy, information system and robot selection problem:1. Fuzzy consensus-based possibility measure and goal programming approach.2. Fuzzy consensus-based neat OWA and goal programming approach.3. Fuzzy consensus-based goal programming and TOPSIS approach.Finally, a comparison of these three approaches is conducted and thus was able to give recommendations to improve the approaches and provide decision aid to the most satisfying decision makers.
56

Aplikace vícekriteriálního rozhodování ve výrobním podniku / The application of multicriteria evaluation of alternatives in manufacturing company

Vondra, Pavel January 2008 (has links)
The target of this thesis is to derermine the quality of the aluminium base alloy and size of aluminium plates used for mountain bike equipment. Furthermore the thesis assigns one provider of this material for Shaman Racing company. There were chosen methods of multicriteria evaluation of alternatives to fulfill the target. These methods are ORESTE, TOPSIS and ELECTRE I. The thesis also proves the possibilities of practical application of determined methods and analyzes possible problems that could occur during handling the input data and process of selecting the "best" alternative.
57

Hodnocení krajů z pohledu vícekriteriálního rozhodování / Evaluation of territories in view of the multicriteria desicion making

Vařbuchtová, Marie January 2009 (has links)
This diploma thesis as is mentioned on its title, deals with confrontation of the single territories of the Czech Republic. Plentitude of data was gathered together in other to make this camparison. These data were chosen with regard to the real--life decisions. Multicriteria decision making methods were used as an instrument for comparison making.
58

Utveckling av arbetsprocess för effektivare produktutveckling : Tillämpad på standardisering av helautomatiskt snabbfäste till hjullastare

Clark, Eric, Olsson, David January 2021 (has links)
För att vara konkurrenskraftiga på marknaden tvingas företag utveckla nya strategier för produktutveckling, som kan anpassas till allt högre kundbehov. Syftet med detta arbete var att effektivisera produktutvecklingen för företag inom tillverkningsindustrin. Målet var att utveckla en effektiv arbetsprocess för produktutveckling samt att tillämpa processen på ett projekt, där ett helautomatiskt snabbfäste till mindre hjullastare skulle standardiseras till företaget OilQuick.Examensarbetet delades in i två delar. Den första delen behandlar skapandet av arbetsprocessen. Denna grundas i befintlig forskning och identifierades genom en litteraturstudie. Den andra delen behandlar tillämpning av arbetsprocessen på standardiseringen av snabbfästet till hjullastare. Data och kunskap till arbetet samlades in genom marknadsundersökningar, studiebesök, möten med kunder och Reverse Engineering. Kundkraven rangordnades med Best-worst metoden och översattes till tekniska produktegenskaper med Kvalitetshuset.Tre koncept genererades i Autodesk Inventor utifrån kraven och produktegenskaperna, samt datan som framkom av Reverse Engineering och marknadsundersökningen. Enligt kundkravet behövde det färdiga snabbfästet passa minst fyra olika hjullastarmodeller i viktklassen fem till åtta ton. Detta medförde att alla tre koncepten modulbaserades, både för att underlätta eventuella modifikationer mellan hjullastarmodellerna och för att minimera antalet detaljer som behövde modifieras. Alla tre konceptens redskapsgrindar hade standardiserade mått som passade de undersökta hjullastarmodeller. Det koncept som bäst uppfyllde kundkraven utvärderades med Fuzzy TOPSIS metoden. Det slutgiltiga konceptet justerades utifrån kundens önskemål innan det färdiga resultatet presenterades.Resultatet visade att arbetsprocessen var effektiv; Reverse Engineering och samarbetet med kunden gav en inblick i problematiken och förståelse för produkten, Best-worst metoden gjorde att rangordningen av kraven gick snabbt utan att minska på pålitligheten och Fuzzy TOPSIS metoden effektiviserade konceptvalet samtidigt som alla inblandades åsikter blev hörda. För att effektivisera produktutvecklingen ytterligare bör fler metoder undersökas alternativt utvecklas.Konceptförslagen som konstruerades påvisade att det är möjligt att standardisera gränssnittet mellan hjullastare och redskap. Genom modulärkonstruktion kunde snabbfästet anpassas till fyra olika hjullastarmodeller. Innan vidareutveckling av snabbfästet bör fler hjullastare mätas upp och studeras. / In order to be competitive in the market, companies are forced to develop new strategies that can be adapted to ever-increasing customer requirements. The purpose of the work was to streamline product development for companies in the manufacturing industry. The objective was to develop an efficient work process for product development and apply the process to a project where a standardized fully automatic quick coupler for smaller wheel loaders would be developed for the company OilQuick.The thesis was divided into two parts. The first part deals with the development of a work process based on existing research. The second part deals with the application of the work process. Data for the application was collected through market research, meetings with customers and Reverse Engineering. Customer requirements were ranked using the Best-worst method and translated into technical specifications using the method QFD (House of Quality).Three concepts were generated based on the resulting requirements from the QFD. According to the customer requirements, the quick coupler had to be compliant with at least four different wheel loader brands in the weight span from five to eight tons. This meant that all three concepts were based on modular design, both to facilitate modifications between the wheel loader brads and to minimize the number of details that needed to be modified. All three of the concept's attachment brackets had standardized dimensions that fitted all examined wheel loader models. To determine which concept that best met the customer requirements the Fuzzy TOPSIS method was used. The final concept was adjusted based on OilQuick's requirements before the finished result was presented.The results showed that the work process was efficient and reliable and that the developed concept proposal indicates that it is possible for the company to standardize the interface between wheel loaders and attachments. With modular design the quick coupler can be adapted to the wheel loader brands that were studied. To ensure that the quick coupler can be applied to a larger variety of wheel loaders, it is necessary to examine and take measurements of more wheel loader brands before further development.
59

[pt] MONITORAMENTO E AVALIAÇÃO DO PLANO MUNICIPAL DE SANEAMENTO BÁSICO DE VITÓRIA COM ÊNFASE NOS SEUS PROGRAMAS DE ÁGUA TRATADA E ESGOTAMENTO SANITÁRIO: PROPOSIÇÃO DE INDICADORES E MÉTRICAS / [en] MONITORING AND EVALUATION OF THE MUNICIPAL PLAN OF BASIC SANITATION OF VITORIA WITH EMPHASIS ON ITS PROGRAMS OF TREATED WATER AND SANITARY SEWAGE: PROPOSAL OF INDICATORS AND METRICS

CECILIA MONTIBELLER OLIVEIRA 31 July 2019 (has links)
[pt] O saneamento básico, constitui-se como fator essencial para o desenvolvimento do país. A Lei número 11.445/2007, estabelece a obrigatoriedade da elaboração dos Planos Municipais de Saneamento Básico (PMSB), no intuito de eliminar ou minimamente reduzir a distribuição desigual do acesso aos serviços. O objetivo geral da dissertação é propor um modelo de avaliação de PMSBs que permita identificar os conteúdos previstos na legislação, avaliando também a qualidade dessas informações, com enfoque no monitoramento e avaliação dos programas de abastecimento de água tratada e esgotamento sanitário, com o auxílio de um método híbrido multicritério de apoio à decisão. A pesquisa pode ser considerada aplicada, descritiva e metodológica. A metodologia compreendeu pesquisa bibliográfica e documental; adaptação do Roteiro de Avaliação de PMSB, no intuito de qualificar os planos; construção de um quadro lógico de programas de saneamento básico para a posterior proposição de indicadores candidatos e respectivas métricas; emprego de um método híbrido de apoio à decisão; e desenvolvimento de um estudo realizado no âmbito dos Programas de abastecimento de água tratada e esgotamento sanitário propostos pelo PMSB de Vitória, visando demonstrar a aplicabilidade do modelo. Destacam-se como resultados um novo modelo avaliação de PMSB e de monitoramento e avaliação (MA) de programas de saneamento básico, propostos pelos PMSBs; a ferramenta de seleção e classificação de indicadores visando à melhoria contínua de programas de saneamento básico e dos PMSBs; e um conjunto consistente de 17 indicadores de MA para o programa de abastecimento de água tratada e 14 indicadores para o programa de esgotamento sanitário do PMSB de Vitória. / [en] The basic sanitation, guaranteed by the Federal Constitution and defined by Law No. 11,445 / 2007, National Basic Sanitation Law as the set of services, infrastructure and operational facilities for water supply, sanitary sewage, urban cleaning, urban drainage, of solid waste and rainwater, is an essential factor for the development of the country. Defined by Demoliner (2008, p. 174) as one of the most sensitive and deficit sectors of the country, basic sanitation includes measures aimed at preserving or modifying environmental conditions in order to prevent diseases and promote health, quality of life of the population and the productivity of the individual, facilitating economic activity. With that being said, aiming at the universalization of sanitation services and improvement of the sanitary conditions of Brazilian municipalities, Law No. 5 was established on January 5, 2007. 11.445 - National Policy on Basic Sanitation, which determines national guidelines for the sector, establishing principles of universality, integrality and social control as differential factors in the struggle for quality of life, providing everyone with the right of access to basic sanitation. Characterized as a regulatory framework for universal access to basic sanitation, Law 11.445 / 07 establishes the obligation to elaborate the Water and Sanitation Municipal Planning (WSMP), encompassing the entire territory of the municipality in order to eliminate or minimally reduce the unequal distribution access to services (Mota, 2008). It is evidenced that the WSMP evaluates the state of environmental health, including the provision of public services, defining the schedule of actions and investments required to provide basic sanitation services, defined as a set of guidelines, studies, programs, projects, priorities, goals, normative acts and procedures. In this way, the plan acts as a strategic management tool for municipalities, service holders.
60

[en] ENERGY GENERATION IN ISOLATED SYSTEMS: CHALLENGES AND PROPOSALS FOR INCREASING THE SHARE OF RENEWABLES BASED ON A MULTICRITERIA ANALYSIS / [pt] GERAÇÃO DE ENERGIA ELÉTRICA EM SISTEMAS ISOLADOS: DESAFIOS E PROPOSTAS PARA AUMENTO DA PARTICIPAÇÃO DE FONTES RENOVÁVEIS COM BASE EM UMA ANÁLISE MULTICRITÉRIOS

GUSTAVO PIRES DA PONTE 12 December 2019 (has links)
[pt] Os cerca de 250 Sistemas Isolados do Brasil, concentrados na região Norte, representam aproximadamente 1 por cento do consumo nacional de energia elétrica, sendo historicamente atendidos por meio de geradores a diesel, uma solução cara, poluente e dependente de uma complexa logística de fornecimento de combustível. Apesar de diversas publicações indicarem que fontes renováveis já são técnica e economicamente viáveis, sobretudo em economias dependentes de combustíveis caros, a geração a partir do diesel ainda predomina nessas localidades. Esta dissertação tem por objetivo hierarquizar propostas de políticas públicas, visando à inserção de fontes renováveis nos sistemas isolados do Brasil, por meio de uma ferramenta de análise multicritério. Com isso, ter-se-á a transição de dependência em combustíveis fósseis para uma economia baseada em energias renováveis. Para subsidiar a seleção e hierarquização dessas propostas, indo além das habituais avaliações técnico-econômicas, criou-se um modelo utilizando os métodos multicritério de apoio à decisão AHP e fuzzy-TOPSIS, por serem ferramentas reconhecidas como ideais para a modelagem de problemas em que subjetividade, incerteza e ambiguidades estejam presentes. Como resultado, concluiu-se que a política pública de maior impacto seria a implantação de projetos-piloto de usinas híbridas, combinando geração a diesel com fotovoltaica, por exemplo, de forma a auxiliar a transposição de barreiras culturais e de conhecimento sobre tecnologias alternativas nos sistemas isolados. Outras políticas apontadas como relevantes seriam: a simplificação do licenciamento ambiental de projetos baseados em fontes renováveis e a adoção de um modelo de planejamento determinativo, exigindo nos leilões uma penetração mínima dessas fontes. / [en] Isolated systems are those places not connected to the national grid, for technical or economic reasons and supplied by local generation. Nowadays in Brazil, there are about 250 isolated systems, concentrated in the Northern region, which sums only 1 percent of the electricity total consumption of the country, but represents around 40 percent of the territory. Most of these systems are supplied by diesel power plants, with a few examples of generation by natural gas, biomass or small-hydro. Historically, the diesel gensets have been an easy solution, due to its facility to build, operate and maintain. Also, these power plants do not require complex projects and large areas and have relatively low investment cost associated. Despite the complex logistics of fuel supply, mostly done by boats along Amazonian rivers, the energy generation has worked quite well in the last decades. However, the operational costs, especially those related to the fuel, are very high. In some places, depending on the season and navigability, it can reach R$ 10/liter (around US$ 3/l), resulting in high generation costs, that can achieve R$ 1,600/MWh (around US$ 450/MWh). All electricity consumers in Brazil share a great part of this cost. Other problems related to the diesel-based generation are the pollutant and greenhouse gases emissions, in the middle of the Amazon forest, where most of the isolated systems are located. Some effort has been made to connect isolated systems to the national grid, reducing the local generation, and consequently, its costs and emissions. However, the expansion of conventional power grid has high costs and, in some cases, technical and environmental constraints (Ribeiro, et al., 2012).

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