Made available in DSpace on 2014-06-11T19:22:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-03-22Bitstream added on 2014-06-13T18:08:34Z : No. of bitstreams: 1 silva_mv_me_ilha.pdf: 743779 bytes, checksum: 5aad49dd95d63ada483f753bee811fd7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho, otimiza-se o funcionamento de uma fábrica desidratadora de forragens localizada na Espanha. Esta possui processos seqüenciados, secagem, produção de fardos de feno e produção de grãos, que para serem realizados consomem quantidades distintas de energia. Estabelecem-se então, os períodos de produção para cada processo, juntamente com a quantidade em toneladas a serem produzidas, sabendo que na Espanha a energia elétrica possui vinte e quatro preços, um para cada hora do dia. É proposto um modelo para a função objetivo, utilizando dados históricos de produção (Ton), consumo (kWh) e tempo (h), que retratará o funcionamento da empresa. Este modelo é obtido por meio de regressão linear múltipla e é implementado utilizando o software Lingo. Os resultados dessa implementação fornecerão as horas totais diárias que cada processo deverá ser realizado, juntamente com a quantidade de toneladas de pacotes de feno e grãos, e o custo diário da energia elétrica para realizar a produção. / In this work, optimize of the functioning of a plant that dehydrates fodder plants located in Spain. This possess sequenced processes, drying, production of hay packs and production of grains, which to be carried through consumes distinct amounts of energy. Then, the periods of production for each process are established, together with the amount in tons to be produced, knowing that in Spain the electric energy possess twenty and four prices, one for each hour of the day. It is considered a model for the objective function, by using given historical data of production (Ton), consumption (kWh) and time (h), that the functioning of the company will portray. This model is gotten by means of multiple linear regression and is implemented using software Lingo. The results of this implementation will supply the daily total hours that each process will have to be carried through, with the amount of tons of packages of hay and grains , and the daily cost of the electric energy to carry through the production.

Este trabalho apresenta um modelo linearizado para ser utilizado em problemas de planejamento da expansão de sistemas de distribuição de energia elétrica (SDEE) com geração distribuída (GD), em um horizonte de curto prazo. O ponto de operação em regime permanente é calculado através de um modelo linearizado da rede, sendo as cargas e geradores representados por injeções constantes de corrente, o que torna possível calcular as correntes nos ramos e as tensões nas barras através de expressões lineares. As alternativas de expansão consideradas são: (i) alocação de bancos de capacitores; (ii) alocação de reguladores de tensão; e (iii) recondutoramento. Ainda, o modelo considera a possibilidade de seleção do tap dos transformadores de distribuição como alternativa para a redução das violações de tensão. A flexibilidade do modelo permite obter soluções considerando a contribuição das GDs no controle de tensão e potência reativa sem a necessidade de especificar uma tensão para a barra da subestação. O modelo de otimização proposto para a solução destes problemas utiliza uma função objetivo linear, além de restrições lineares e variáveis contínuas e binárias. Dessa forma, o modelo de otimização pode ser representado como um problema de programação linear inteira mista (PLIM) A função objetivo considera a minimização dos custos de investimento (aquisição, instalação e remoção de equipamentos e aquisição de condutores) e dos custos de operação, que correspondem aos custos anuais de manutenção somados aos custos das perdas de energia e das violações dos limites de tensão. A variação da carga é representada através de curvas de duração, sendo que os custos das perdas e das violações são ponderados pela duração de cada nível de carregamento. Utilizando uma abordagem de PLIM, sabe-se que existem condições suficientes que garantem a otimalidade de uma dada solução factível, além de permitir que a solução seja obtida através de métodos de otimização clássica. O modelo proposto foi implementado na linguagem de programação OPL e resolvido utilizando o solver comercial CPLEX. O modelo foi validado através da comparação dos resultados obtidos para cinco sistemas de distribuição com os resultados obtidos utilizando um fluxo de carga convencional. Os casos analisados e os resultados obtidos demonstram a precisão do modelo proposto e seu potencial de aplicação. / This work presents a linearized model to be used in short-term expansion planning problems of power distribution systems (PDS) with distributed generation (DG). The steady state operation point is calculated through a linearized model of the network, being the loads and generators modeled as constant current injections, which makes it possible to calculate the branch currents and bus voltages through linear expressions. The alternatives considered for expansion are: (i) capacitor banks placement; (ii) voltage regulators placement; and (iii) reconductoring. Furthermore, the model considers the possibility of adjusting the taps of the distribution transformers as an alternative to reduce voltage violations. The flexibility of the model enables solutions that includes the contribution of DGs in the control of voltage and reactive power without the need to specify the substation voltage. The optimization model proposed to solve these problems uses a linear objective function, along with linear constraints, binary and continuous variables. Thus, the optimization model can be represented as a mixed integer linear programming problem (MILP) The objective function considers the minimization of the investment costs (acquisition, installation and removal of equipment and acquisition of conductors) and the operation costs, which corresponds to the annual maintenance cost plus the costs related to energy losses and violation of voltage limits. The load variation is represented by discrete load duration curves and the costs of losses and voltage violations are weighted by the duration of each load level. Using a MILP approach, it is known that there are sufficient conditions that guarantee the optimality of a given feasible solution, besides allowing the solution to be obtained by classical optimization methods. The proposed model was written in the programming language OPL and solved by the commercial solver CPLEX. The model was validated through the comparison of the results obtained for five distribution systems with the results obtained through conventional load flow. The analyzed cases and the obtained results show the accuracy of the proposed model and its potential for application.

Submitted by Raildo Barros Rodrigues (raildo.barros@gmail.com) on 2018-09-24T15:10:31Z No. of bitstreams: 1 Dissertação_Grade_Horária_Raildo_Marins_Aneirson.pdf: 2926580 bytes, checksum: 6799724ac48abd21caecd50cf5156480 (MD5) / Rejected by Pamella Benevides Gonçalves null (pamella@feg.unesp.br), reason: Solicitamos que realize correções na submissão seguindo as orientações abaixo Verificar formatação com a equipe da biblioteca. Agradecemos a compreensão. on 2018-09-24T18:49:58Z (GMT) / Submitted by Raildo Barros Rodrigues (raildo.barros@gmail.com) on 2018-09-25T16:48:30Z No. of bitstreams: 2 Dissertação_Grade_Horária_Raildo_Marins_Aneirson.pdf: 2926580 bytes, checksum: 6799724ac48abd21caecd50cf5156480 (MD5) Dissertação_Grade_Horária_Raildo_Marins_Aneirson.pdf: 2944631 bytes, checksum: d0f33c161c9cb711a7b75cd2666f0470 (MD5) / Approved for entry into archive by Pamella Benevides Gonçalves null (pamella@feg.unesp.br) on 2018-09-25T18:15:24Z (GMT) No. of bitstreams: 1 rodrigues_rb_me_guara.pdf: 2944631 bytes, checksum: d0f33c161c9cb711a7b75cd2666f0470 (MD5) / Made available in DSpace on 2018-09-25T18:15:24Z (GMT). No. of bitstreams: 1 rodrigues_rb_me_guara.pdf: 2944631 bytes, checksum: d0f33c161c9cb711a7b75cd2666f0470 (MD5) Previous issue date: 2018-09-20 / Outra / Esta dissertação trata da construção de um modelo matemático para a elaboração do quadro de horários dos cursos de graduação do CBV/IFRR. A programação de horários é um problema de otimização combinatória estudado há anos pela Pesquisa Operacional e, em termos de complexidade computacional, é tido como NP-Completo, sendo assim, é um problema que exige grande capacidade de processamento. A elaboração do quadro de horários em qualquer instituição de ensino é complexa e demanda tempo para os responsáveis por essa atividade, pois as necessidades dos professores e alunos devem ser atendidas e devem-se evitar conflitos nos horários dos professores. A instituição estudada nesta dissertação assim como outras instituições, possui particularidades institucionais, dessa forma, uma formulação geral do problema acaba não lhe sendo útil. O CBV/IFRR realiza a elaboração dos horários de forma manual, por meio de planilha eletrônica e realização de reuniões entre os gestores, o que torna difícil encontrar uma solução factível. Sendo assim, foi necessária a realização de pesquisa científica para encontrar métodos que poderiam ser aplicados ao problema. Assim, este trabalho teve como objetivo desenvolver um modelo de Programação Matemática que permitisse a elaboração dos horários para cursos de graduação do CBV/IFRR. Utilizou-se entrevistas com as Coordenações de Cursos para obtenção das informações acerca do problema tratado, tais como restrições e prioridades a serem atendidas com a programação de aulas para professores. Estas informações serviram de base para a construção do modelo conceitual, que foi utilizado para elaboração do modelo matemático final, que foi implementado na linguagem de alto nível GAMS® e resolvido pelo solver CPLEX®. Os testes do modelo foram realizados otimizando uma instância com dados reais da instituição estudada. Os resultados obtidos da otimização foram satisfatórios, pois foi possível encontrar uma solução ótima para a instância em tempo computacional adequado, com todas as restrições, impostas pelas características peculiares do problema tratado, sendo respeitadas e as prioridades estabelecidas pelas Coordenações de Cursos atendidas. / This dissertation deals with the construction of a mathematical model for the elaboration of the timetable of the undergraduate courses of the CBV/IFRR. Time scheduling is a combinatorial optimization problem that has been studied for years by Operational Research and, in terms of computational complexity, is considered as NP-Complete, so it is a problem that requires large processing capacity. The elaboration of the timetable in any educational institution is complex and takes time for those responsible for this activity, because the needs of teachers and students must be met and avoid conflicts in the schedules of teachers. The institution studied in this dissertation as well as other institutions, has institutional features, so a general formulation of the problem ends up being of no use to it. The CBV/IFRR performs the elaboration of the schedules manually, through a spreadsheet and holding meetings between managers, which makes it difficult to find a feasible solution. Thus, it was necessary to carry out scientific research to find methods that could be applied to the problem. Thus, this work had the objective of developing a Mathematical Programming model that allowed the elaboration of the schedules for the undergraduate courses of the CBV/IFRR. We used interviews with the Course Coordinators to obtain information about the problem, such as constraints and priorities to be met with the programming of classes for teachers. This information was the basis for the construction of the conceptual model, which was used to elaborate the final mathematical model, which was implemented in the GAMS® high-level language and solved by the CPLEX® solver. The tests of the model were performed optimizing an instance with real data of the studied institution. The results obtained from the optimization were satisfactory, since it was possible to find an optimal solution for the instance in adequate computational time, with all the restrictions imposed by the peculiar characteristics of the problem, being respected and the priorities established by the Coordination of Courses attended.

A presente pesquisa considera o problema de programação de uma frota de embarcações de lançamentos de dutos, conhecidas como Pipe Layer Support Vessel (PLSVs), as quais fazem parte da frota de apoio marítimo de uma operação offshore. As embarcações do tipo PLSVs são responsáveis pelas tarefas de lançamento de dutos submarinos, que escoam a produção dos poços de petróleo, e pela interligação destes dutos à infraestrutura submarina. A programação da frota deve atender uma demanda de serviço conhecida, em um horizonte de médio prazo, respeitando restrições operacionais, visando minimizar o atraso ponderado total das tarefas ou evitar que existam atrasos. Foi desenvolvido um método para estimar o valor da solução ótima do problema, baseado na técnica de relaxação Lagrangiana, e um conjunto de heurísticas para gerar soluções viáveis para o problema. / This research considers the problem of scheduling a fleet of specialized vessels used for launching pipes and connecting them to the subsea infrastructure, in an offshore oil production environment. The Pipe Layer Support Vessels (PLSV) must be scheduled such that the demand is fully attended within the planning horizon, observing other operational constraints, with the purpose of minimizing the total weighted tardiness. The solution method is based on constructive and local search heuristics. Bounds on the optimal solution were derived by a Lagrangean relaxation algorithm.

Dans plusieurs pays européens, la capacité de l’infrastructure est complètement exploitée aux heures de pointe et aux points critiques : une grande quantité de trains traversent ces points critiques dans un laps de temps très réduit. Dans cette situation le retard d’un train provoqué par un conflit de circulation peut se propager dans tout le réseau. Le problème de la gestion opérationnelle du trafic ferroviaire consiste à trouver les modifications des itinéraires et des ordonnancements des trains qui minimisent la propagation des retards. Dans cette thèse, nous proposons une approche de décomposition de Benders pour la formulation linéaire en nombres entiers à variables mixtes utilisée dans l’algorithme RECIFE-MILP. Après avoir constaté que l’approche de décomposition standard de Benders ne permet pas de trouver rapidement une solution de bonne qualité pour certaines instances du problème, nous étudions trois approches alternatives afin d’améliorer la performance de notre algorithme. Nous proposons d’abord une approche que nous appelons la reformulation réduite de Benders. Ensuite, nous introduisons des inégalités dans la formulation du problème maître de Benders. Finalement, nous scindons le processus de résolution en trois étapes au lieu de deux comme dans la décomposition standard de Benders. L'analyse expérimentale montre que la combinaison de la première et dernière approche surpasse l’algorithme original RECIFE-MILP dans la résolution de grandes instances sous certaines conditions. / In railway systems, during congested traffic situations, the infrastructure capacity is completely exploited for trains circulation. In these situations, when traffic is perturbed some trains must be stopped or slowed down for ensuring safety, and delays occur. The real-time Railway Traffic Management Problem (rtRTMP) is the problem of modifying trains route and schedule to limit delay propagation. In this thesis, we propose a Benders decomposition of a MILP-based algorithm for this problem, named RECIFE-MILP. After observing that the standard Benders decomposition (BD) does not allow the effective solution of rtRTMP instances, we study three possible approaches to improve the performance. Specifically, we first propose a modification of the problem reformulation which is typical of BD, obtaining what we call reduced BD. Then, we introduce some inequalities to the Benders master problem. Finally, we split the solution process in three steps rather than two as in the standard BD. As we show in a thorough experimental analysis, the combination of the first and last approaches outperforms the original RECIFE-MILP algorithm when tackling large instances with some specific features.

De senaste åren har en större mängd decentraliserad och variabel energiproduktion tagit plats inom elsystemet, mer specifikt vindkraft och solkraft, och etablering av mer distribuerad produktion kommer att fortsätta i enlighet med mål från nationer och världsorganisationer att fasa ut fossila bränslen och minska på växthusgasutsläpp. I takt med nedläggning av storskaliga kraftverk baserade på fossila bränslen påverkar detta möjligheterna att möta upp elbehovet med den tillgängliga produktionen. Mycket variabel produktion har samtidigt en negativ påverkan på elnätstabiliteten och kan skapa höga effekttoppar. Detta har skapat ett ökat behov av mer flexibilitet på kundsidan för att skapa balans på elnätet. Elektrokemiska batterilager kan lösa många av problemen som uppstår med intermittent förnybar energiproduktion. Batterilager har både utvecklats teknologiskt och minskats i pris avsevärt de senaste tio åren och kostnaderna kommer fortsätta att gå ned. För att batterilager på allvar ska bli intressant behöver aktörer som investerar i denna teknologi veta om det någon gång inom en snar framtid kommer att vara en positiv affär. Syftet med detta arbete har därför varit att undersöka lönsamheten med batterilager i kommersiella fastigheter idag och inom de närmsta 10 åren på den svenska marknaden. Studien har, med hjälp av blandad heltalsprogrammering (MILP) i MATLAB, tagit fram en modell som optimalt schemalägger energiflöden för en fastighet som har ett batterisystem och egen produktion installerat baserat på olika prisbilder. Modellen har i sin tur använts för att beräkna de ekonomiska möjligheterna som erbjuds på Sveriges elmarknad med ett batterisystem i en mängd olika scenarier både vad gäller pris på el, olika effektabonnemang, integration med solpaneler, olika batteristorlekar och systemlivslängd. Resultatet visar att det inte finns någon lönsamhet i att investera i batterier för de undersökta fastigheterna så som Sveriges elmarknad ser ut idag och någon hög lönsamhet kommer inte att ske även om pristrenden på batterier fortsätter nedåt. Ett mindre batterisystem på 28 kWh kan ge, beräknat med internräntan, en positiv avkastning på 1 % år 2020 men ju större batteriet är desto mindre blir avkastningen. Högst avkastningen som kan fås med dagens el- och nätpriser är 4-5 % om en investering görs med 2025-2030 års batteripriser. Om elnätsägarna går mot att endast erbjuda tidsdifferentierade nättariffer året om och det implementeras högre effektavgifter finns det möjligheter att avkastningen kan bli så hög som 15-18 % med 2025-2030 års batteripriser. Arbetet visar också att kapandet av effekttoppar med större batterilager än 28 kWh inte är kostnadseffektivt för de undersökta fastigheterna. / The world has seen a rapid deployment of distributed and time-varying renewable energy systems (RES) within the electricity grids for the past 20 years, especially from wind and solar power. The deployment RES is expected to increase even more as world organizations and nations will continue the phase-out of fossil fuels as the main source of energy for electricity production. As large scale power plants reliant on fossil fuels will shut down it will be harder for the system to balance production and demand. At the same time, time-varying production might have a negative effect on the grid stability which has spurred an increased interest in flexibility on the demand side and a call for technologies and strategies that can create balance on the grid. Energy storage, especially electrochemical battery storage, is seen as a part of a bigger solution to the problems that comes with intermittent energy production. Battery storage has had a fast technological development and a sharp downtrend in pricing the latest ten years and the costs are expected to keep on decreasing. For battery storage to be a serious contender on the electricity market there is a need to understand if and when an investment in this technology might give a positive outcome. The aim of this study has therefore been to analyse the profitability of battery storage within commercial real estate today, and in the oncoming 10-15 years on the Swedish electricity market. The study has, using mixed integer linear programming (MILP) within MATLAB, created a model which optimally schedules power flows for buildings that has a battery system and its own electricity production. The model has in turn been used to evaluate the economical possibilities that exist with a battery system within commercial real estate under various different scenarios that looks into pricing structures on electricity and demand, integration with and without solar panels, different battery sizes and system lifetimes. The results show that there is currently no profitability to invest in a battery system for the specific buildings analysed in this study. While break-even is possible just a couple of years from now, a high profitability will not be reached even with the future downtrend in battery prices under the current electricity market circumstances. A smaller battery system with a capacity of 28 kWh could give an internal rate of return (IRR) of 1 % year 2020. Larger battery systems are generally not cost-effective when compared to smaller battery systems when its primary purpose is utilized for demand reduction. Highest return with today’s electricity and utility pricing is 4-5 % somewhere between 2025 and 2030. However, if the market goes towards exclusively time-of-use billing structures on electricity and higher demand charges, the IRR can reach towards 15-18 % between 2025 and 2030.

[pt] As doenças vasculares são enfermidades graves e seus tratamentos são complexos e necessitam de procedimentos cirúrgicos. Para a realização desses procedimentos, são necessários equipamentos, equipes qualificadas e unidade de terapia intensiva (UTI) equipada para o pós-operatório. Hospitais de ensino devem atender à legislação vigente que preconiza um número mínimo de cirurgias para aprovação do residente no programa de formação. Assim, propõe-se, via otimização, encontrar soluções eficientes para o planejamento e programação de cirurgias eletivas que atendam à legislação. Este problema é tratado em 2 níveis. O primeiro é relativo ao planejamento e é chamado de Master Surgical Schedule (MSS) que consiste em definir os recursos necessários para a realização de um conjunto de procedimentos. O segundo se refere à programação e é chamado de Surgical Case Assigment Problem (SCAP) e tem por objetivo alocar o médico a cada cirurgia. Assim, foram propostos dois modelos de programação matemática, um para o MSS e outro para o SCAP. Estes modelos foram aplicados no caso real da alocação de residentes para cirurgias vasculares no Hospital Universitário Pedro Ernesto. Como resultado do modelo MSS, identificou-se a necessidade de mais anestesistas e maior disponibilidade de equipamentos para atender à legislação de formação de residentes. Por fim, como resultado do SCAP, o quantitativo de cirurgias foi distribuído entre os cirurgiões de forma balanceada. / [en] Vascular diseases are serious diseases and their treatments are complex and require surgical procedures. In order to perform these procedures, is required equipment, qualified teams and an intensive care unit (ICU) equipped for the postoperative period. Teaching hospitals must comply with current legislation that recommend a minimum number of surgeries for the resident s approval in the training program. Thus, it is proposed, through optimization, to find efficient solutions for the planning and programming of elective surgeries that comply with the legislation. This problem is dealt with on two levels. The first is relative to planning and is called the Master Surgical Schedule (MSS), which consists of defining the necessary resources to perform a set of procedures. The second one refers to programming and is called Surgical Case Assigment Problem (SCAP) and aims to allocate the doctor to each surgery. Thus, two models of mathematical programming were proposed, one for MSS and another for SCAP. These models were applied in the real case of residents allocation for vascular surgeries at Pedro Ernesto University Hospital. As a result of MSS model were identified the need for more anesthesiologists and greater availability of equipment ensure the cover of resident training legislation. Finally, as a result of SCAP, the quantity of surgeries was distributed equitably distributed among surgeons.

This diploma thesis deals with optimization models with design of a new waste management infrastructure in the Czech Republic, such that combustible waste, which is not utilized by the material recovering, can be used by energy recovering. This task is handled by optimization models, including trac and mixing problems. First of all, the concepts of graph theory and optimization are presented in this paper. Subsequently, some of the GAMS functions are discussed, and later the VBA programming language used to handle the larger data quickly is presented. In the main part, three gradually expanding models are developed. At the end the data from the waste management information system are implemented into them.

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The development of sustainable business models is a challenging task since various factors might influence the results of an assessment. Given the complexity at the municipal level, system interdependencies between different alternatives need to be considered. One possibility to support decision makers is to apply energy system optimization models. Existing optimization models, however, ignore the roles different actors play and the resulting impact they have. To address this research issue, this thesis presents an integrated techno-economic optimization framework called IRPopt (Integrated Resource Planning and Optimization). A proven graph-based energy system approach allows the accurate modeling of deployment systems by considering different energy carriers and technical processes. In addition, a graph-based commercial association approach enables the integration of actor-oriented coordination. This is achieved by the explicit modeling of market actors on one layer and technology processes on another layer as well as resource flow interrelations and commercial agreements mechanism among and between the different layers. Using the optimization framework, various optimization problems are solvable on the basis of a generic objective function. For demonstration purposes, this thesis assesses the business models demand response and community storage. The applied examples demonstrate the modeling capabilities of the developed optimization framework. Further, the dispatch results show the usefulness of the described optimization approach.