[pt] Esta dissertação tem como objetivo contribuir para o gerenciamento de frotas de grande porte, buscando uma maior rapidez e eficiência na distribuição de veículos ao longo do tempo/espaço, visando maximizar o lucro total da empresa. Problemas de gerenciamento de frotas dinâmicas são normalmente formulados como uma rede dinâmica, mas há uma grande dificuldade ao se trabalhar com problemas desse tipo, especialmente quando se busca uma solução sobre um horizonte de planejamento longo. Visando contornar essa dificuldade, Powell & Carvalho (1998) desenvolveram uma nova abordagem para problemas desse tipo: a Logistics Queuing Network (LQN). A utilização do algoritmo LQN na prática (através de um software) permitiria uma tomada de decisão mais rápida e eficiente, sendo bastante útil, em especial para empresas de transportes. Assim, implementou-se o algoritmo LQN, através do desenvolvimento de um software para o gerenciamento de frotas de grande porte, por meio do qual podese constatar o potencial de aplicação desse algoritmo. / [en] The objective of this dissertation is to contribute to the large-scale fleet management, looking for a greater efficiency and speed in vehicle distribution over time and space, while maximizing total profit. Dynamic fleet management problems are normally formulated as a dynamic network, but it`s really difficult to work with problems of this class, especially when we look for a solution over a large planning horizon. In order to overcome this problem, Powell & Carvalho (1998) developed a new formulation for these problems: the Logistics Queuing Network. The use of its algorithm in real problems (using a software) would allow quickly and more efficient decisions in transports, being really useful especially for transports enterprises. For this reason, the algorithm LQN was implemented, through the development of a software for the large-scale fleet management, so we could verify the potential application of this algorithm.

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För att skapa ett hållbart transportsystem och uppnå en förändrad färdmedelsfördelning finns det nationella målsättningar om att öka andelen persontransporter med gång-, cykel- och kollektivtrafik till minst 25 procent 2025. En satsning på dessa färdmedel går också i linje med Sveriges miljömål och etappmålet om att minska transportsektorns klimatutsläpp med 70 procent till 2030 jämfört med utsläppsnivån 2010. Många kommuner har därför som mål att öka resorna med de hållbara transportslagen. För att möjliggöra detta är en ökad planering och utbyggnad av infrastrukturen för dessa färdmedel viktig och i flera kommuner görs det idag gatuombyggnader för att skapa mer utrymme till de hållbara transportslagen. När åtgärder för att förbättra infrastrukturen ska genomföras ställs olika intressen och funktioner mot varandra och prioriteringar måste göras. Detta leder till intressekonflikter mellan de olika trafikslagen, men också mellan de olika trafikslagen och andra intressen. Syftet med uppsatsen är att undersöka vad det finns för intressekonflikter mellan cykeltrafiken och andra intressen i gaturummet, vad som händer om utrymmesbehovet för cykeltrafiken hamnar i konflikt med andra behov och intressen och hur detta hanteras av ett antal kommuner. Detta har undersökts genom en metodkombination bestående av en enkätundersökning och intervjuer. Både respondenterna och intervjudeltagarna arbetar vid kommuner som är med i föreningen Svenska Cykelstäder, en förening som arbetar för ökad, bättre och säkrare cykling. Intervjuerna utgör grunden i studien medan enkätundersökningen har varit ett sätt att skapa förståelse för om, och i så fall på vilket sätt olika kommuner upplever att det finns intressekonflikter mellan cykeltrafiken och andra behov och intresse och hur dessa vanligtvis hanteras.  Resultatet från enkätundersökningen visar att alla respondenter upplever att det finns intressekonflikter mellan cykeltrafiken och andra intressen. Studien visar att det finns intressekonflikter mellan cykeltrafik och biltrafik, kollektivtrafik samt gångtrafik. Det finns också intressekonflikter mellan cykeltrafik och andra intressen såsom stadsliv, grönytor, yta för dagvattenhantering och exploatering. Studien visar också att trots nationella målsättningar som handlar om att prioritera de hållbara transportslagen så är steget från strategi eller ambition till genomförande inte självklart. Bilnormen är fortfarande stark, vilket medför att det är svårt att genomföra åtgärder som förbättrar för cykeltrafiken som sker på bekostnad av biltrafiken. Studien visar att cykeltrafiken har svårt att hävda sig gentemot biltrafik och kollektivtrafik, vilket resulterar i att cykeltrafiken nedprioriteras i gaturummet där det redan är trångt. Detta förklaras med hjälp av teorierna stigberoende och urban space wars. Studien visar också att det underlag som de tillfrågade kommunerna har för att hantera intressekonflikter är vanligtvis kommunernas riktlinjer för hur cykeltrafikens infrastruktur ska utformas. Där anges vilka standarder och bredder som cykelvägnätet ska ha, vilket innebär att det underlag som finns för att hantera intressekonflikter är begränsat. / To enable a sustainable transport system and achieve a changed distribution of means of transport, there are national objectives to increase the proportion of passenger transport by foot, bicycle and public transport to at least 25 percent by 2025. An investment in these means of transport is also in line with Sweden's environmental goals and the milestone goal of reducing the transport sector's climate emissions by 70 percent by 2030 compared to the emission level in 2010. Many municipalities therefore aim to increase journeys with sustainable modes of transport. In order to make this possible, increased planning and expansion of the infrastructure for these means of transport is important, and in several municipalities’ street reconstruction is currently being done to create more space for the sustainable modes of transport. When measures to improve the infrastructure are being implemented, different interests and needs are placed against each other, and priorities must be defined. This results in a conflict of interest between the different means of transport, but also between the different means of transport and other interests. The purpose of the essay is to investigate what conflicts of interest exist between bicycle traffic and other interests in the street space, what happens if the need for space for bicycle traffic ends up in conflict with other needs and interests, and how this is handled by a number of municipalities. This has been investigated through a combination of methods consisting of a survey and interviews. Both the respondents and the interview participants work at municipalities that are part of the association Svenska Cykelstäder, an association that works for increased, better and safer cycling. The interviews form the basis of the study, while the survey has been a way of creating an understanding of whether, and if so in what way, different municipalities feel that there are conflicts of interest between bicycle traffic and other needs and interests and how these are usually handled. The results of the survey show that all respondents feel that there are conflicts of interest between bicycle traffic and other interests. The study shows that there are conflicts of interest between bicycle traffic and car traffic, public transport and pedestrian traffic. There are also conflicts of interest between bicycle traffic and other interests such as urban life, green spaces, surface for stormwater management and urban development. The study also shows that despite national goals that deal with prioritizing the sustainable modes of transport, the step from strategy or ambition to implementation is not obvious. The car norm is still strong, which means that it is difficult to implement measures that improve bicycle traffic at the expense of car traffic. The study shows that bicycle traffic has difficulty asserting itself against car traffic and public transport, which results in bicycle traffic being deprioritized in the street space which is already crowded. This is explained using the theories of path dependence and urban space wars. The study also shows that the basis that the municipalities have for handling conflicts of interest are usually the municipalities' guidelines for how the bicycle traffic infrastructure should be designed. It specifies the standards and widths that the bicycle road network should have, which means that the guidelines available for handling conflicts of interest are limited.

Submitted by Aelson Maciera (aelsoncm@terra.com.br) on 2017-09-26T19:15:52Z No. of bitstreams: 1 DissCDAC.pdf: 10114021 bytes, checksum: b3e4f52846924539caadab8587fe2250 (MD5) / Approved for entry into archive by Ronildo Prado (bco.producao.intelectual@gmail.com) on 2018-01-26T18:36:20Z (GMT) No. of bitstreams: 1 DissCDAC.pdf: 10114021 bytes, checksum: b3e4f52846924539caadab8587fe2250 (MD5) / Approved for entry into archive by Ronildo Prado (bco.producao.intelectual@gmail.com) on 2018-01-26T18:36:39Z (GMT) No. of bitstreams: 1 DissCDAC.pdf: 10114021 bytes, checksum: b3e4f52846924539caadab8587fe2250 (MD5) / Made available in DSpace on 2018-01-26T18:42:45Z (GMT). No. of bitstreams: 1 DissCDAC.pdf: 10114021 bytes, checksum: b3e4f52846924539caadab8587fe2250 (MD5) Previous issue date: 2017-03-10 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / This work aims at treating the Dynamic Vehicle Allocation Problem (DVAP) in the context of the Brazilian Freight Transportation system. The problem consists of allocating empty vehicles to different terminals so as to attend the demand of freight transport during a predetermined planning horizon while maximizing the profit from these services. These type of decisions arise in customized freight transport services and in between-terminals operations of consolidation freight services. Given the size of the resulting models of real life problems confronted by third party logistics operators are large for using exact solution methods, heuristic methods have been used for giving good quality solution at the expense of optimality guarantee. In this context, the objective of this work is to contribute with solution methods that provide optimality guarantee or quality solution certificates for treating large-scale problems in reasonable computational times. The methods utilized are lagrangean relaxation, using subgradient optimization, and DantzigWolfe decomposition together with a lagrangian heuristic and factibilization method, respectively. Computational experiments are presented and analyzed for randomly generated instances and real-world instances from a brasilian freight operator. The latter method shows great potential for treating large-scale problems. / Este trabalho aborda o problema de Alocação Dinâmica de Veículos (PADV) no contexto de Transporte Rodoviário de Carga. O problema envolve alocar veículos de carga para atender a demanda de transporte de carga prevista entre terminais durante um horizonte de tempo multiperíodos e finito. O objetivo e maximizar o lucro gerado pelos serviços completados. Este tipo de decisões surge nos serviços de transporte de carga de lotação e na parcela de transporte de transferência dos serviços de transporte de carga consolidada. Dado que o tamanho dos problemas que enfrentam as transportadoras logísticas sÃo consideravelmente grandes parase resolver com métodos exatos em tempos computacionais aceitáveis, tem-se utilizado métodos heurísticos para dar boas soluções sem garantia de otimalidade mas em tempos toleráveis a estes problemas. Neste contexto, pretende-se contribuir com métodos de solução que proporcionem garantia de otimalidade e/ou boas soluções aproximadas, acompanhadas de certificados de otimalidade ou de qualidade de solução, para tratar problemas de porte em tempos razoáveis. Os métodos propostos estao baseados em relaxação lagrangiana, utilizando o método de otimização do subgradiente, e na decomposto de Dantzig Wolfe, utilizando a técnica de geração de colunas, além de heurísticas lagrangianas e de factibilização acopladas nestes métodos. Experimentos computacionais usando instâncias geradas aleatoriamente e baseados em dados reais de transportadoras brasileiras sao apresentados e analisados, para as duas abordagens, mostrando seus potenciais de aplicação pratica, principalmente para problemas de grande porte.