Orientador: Orlando Fontes Lima Júnior / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-24T08:54:49Z (GMT). No. of bitstreams: 1 Carvalho_CarolinaCorreade_D.pdf: 5176798 bytes, checksum: 95342f9a296b035e2a6efd2a07ec8e6a (MD5) Previous issue date: 2013 / Resumo: O problema do transporte de produtos refrigerados e congelados é de grande importância e vem sendo cada vez mais estudado. Na cadeia do frio, o controle da temperatura é o fator determinante da qualidade e da validade de produtos alimentícios. Qualquer variação da temperatura fora da faixa padrão especificada ao produto pode levar a danos e perdas. Muitos trabalhos buscam entender o que acontece durante o processo de transporte com a temperatura da carga e do veículo, na qual é possível observar grandes variações deste parâmetro em função dos procedimentos pertencentes ao processo. Alguns elaboram modelos matemáticos que buscam exprimir o comportamento térmico do veículo e da qualidade do alimento em função do tempo decorrido no processo de transporte. Porém, quando se aborda o tema de roteirização de veículo dedicada exclusivamente ao tipo de carga que requer a manutenção adequada da temperatura, nota-se que ainda é uma área em desenvolvimento. Poucos trabalhos fazem uma abordagem de roteirização visando à preservação da qualidade da carga e, consequentemente, a manutenção da temperatura. No geral, modelos de roteirização buscam minimizar as variáveis relacionadas com custos operacionais, quase sempre expressas indiretamente através de medidas de tempo e de distância percorrida pelo veículo. Na sua grande maioria dos estudos, a otimização de problemas de roteirização é obtida com a aplicação de uma heurística do tipo PCV (Problema do Caixeiro Viajante). Entretanto, no processo de roteirização de um veículo envolvendo a distribuição de alimentos refrigerados e congelados, a variável temperatura deve ser incluída neste tipo de modelo, porém com certo cuidado, pois ela não apresenta um comportamento linear durante o percurso. Este cenário exige uma modelagem matemática específica, e obviamente mais complexa que respeite os limites de temperatura específicos ao alimento transportado e, ao mesmo tempo, assemelhe-se a situações reais. Deste modo, o objetivo do trabalho é desenvolver uma metodologia para roteirização dinâmica de veículo que combine o problema da variação da temperatura no transporte de alimento refrigerado e congelado a aspectos logísticos, melhorando assim o cenário atual de perdas e danos deste tipo de mercadoria. Esta metodologia foi aplicada a um cenário hipotético de distribuição utilizando a sequência do PCV. Foi possível constatar que este tipo de sequência, que busca menores distâncias, não consegue garantir as temperaturas ideais da carga transportada. Por outro lado, quando o algoritmo é aplicado novamente buscando soluções de sequências que garantam os índices térmicos e minimizam a distância, soluções ponderadas são obtidas. Além da contribuição acadêmica para a área de roteirização e modelagem dinâmica o presente trabalho visa auxiliar empresas que realizam o transporte e distribuição deste tipo de mercadoria / Abstract: The transportation problem of refrigerated and frozen products is of great importance and is being increasingly studied. In the cold chain, temperature control is determinant of quality and shelf life of food products. Any variation of the temperature product out of range can lead to damage and loss. Many studies seek to understand what happens during the transportation process to load and vehicle temperature, in which is possible observe large variations of that parameter. Some of tham, elaborate mathematical models that express the vehicle thermal behavior and the quality of the food according to elapsed time in the transport process. However, when addressing the issue of routing vehicle dedicated to this type of cargo, we note that it is still a developing area. Few studies make a routing approach in order to preserve the quality of the load and, consequently, the maintenance of temperature. Overall, routing models seek to minimize the variables related to operating costs, often expressed indirectly through measures of time and distance traveled by the vehicle. Mostly, the optimization of routing problems is obtained by applying a heuristic type PCV (TSP). However, in the routing vehicle process involving the distribution of chilled and frozen foods, the temperature variable should be included, but with some atention, since it does not present a linear behavior during the journey. This scenario requires a specific mathematical modeling, and obviously more complex than meets the specific temperature limits to food transported and at the same time, resemble to real situations. Thus, the aim of this work is to develop a methodology for dynamic vehicle routing that combines the problem of temperature variation in the transport of chilled and frozen food with logistics aspects, thus improving the current scenario of loss and damage of this type of products. This methodology was applied to a hypothetical distribution scenario using the sequence of the PCV. It was possible to show that this type of sequence, seeking shorter distances, can not guarantee the cargo optimal temperatures. On the other hand, when the algorithm is applied again looking for solutions that that can ensure thermal indices and minimize the distance, weighted solutions are obtained. Besides contributing to the academic research, the resulting developments will also contribute to the logistic practice, providing the transportation companies with elements to improve the distribution planning and to maintain the temperature limits inside the acceptable levels / Doutorado / Transportes / Doutora em Engenharia Civil

The goal of this diploma thesis was to create four laboratory exercises for the subject "Parallel Data Processing", where students will try on the options and capabilities of Apache Spark as a parallel computing platform. The work also includes basic setup and use of Apache Kafka technology and NoSQL Apache Cassandra database. The other two lab assignments focus on working with a Travelling Salesman Problem. The first lab was designed to demonstrate the difficulty of a task where the student will face an exponential increase in complexity. The second task consists of an optimization algorithm to solve the problem in cluster. This algorithm is subjected to performance measurements in clusters. The conclusion of the thesis contains recommendations for optimization as well as comparison of running with different number of computing devices.

This thesis deals with the Travelling salesman problem with time windows. The problem is that the travelling salesman must pass through each defined location exactly once and finally return to the original place for the lowest possible price. The time windows in this problem are that each place can only be visited in a given time range, or it can happen that in a certain period of time there will be no path between some places. The thesis deals with an overview of this problem and problems similar to it. It also deals with the description of various methods by which this problem can be solved. As part of this thesis, an application in the Python programming language was also created, which is used to test selected methods for finding solutions. Finally, the given experiments are evaluated and the effectiveness of the given strategies is compared.

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A novel Ant Colony Optimization (ACO) framework for a dynamic environment has been proposed in this study. This algorithm was developed to solve Dynamic Traveling Salesman Problems more efficiently than the current algorithms. Adaptive Large Neighborhood Search based immigrant schemes have been developed and compared with existing ACO-based immigrant schemes in literature to maintain diversity via transferring knowledge to the pheromone trails from previous environments. Numerical results indicate that the proposed algorithm can handle dynamicity in the environment more efficiently compared to other immigrant-based ACOs available in the literature. A real-life case study for wildlife surveillance by unmanned aerial vehicles has also been developed and solved using the proposed algorithm.

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Šiame darbe nagrinėjamas patobulintas tabu paieškos metodas, žinomas kaip iteratyvioji tabu paieška (ITP). Pasiūlytos kai kurios ITP metodo modifikacijos, besiremiančios tam tikromis sprendinių mutavimo (pertvarkymo) procedūromis (inversijos, įterpimai ir kt.), kurios įgalina pagerinti gaunamų sprendinių kokybę. Atlikti išsamūs sudaryto ITP algoritmo ir kitų pasiūlytų modifikacijų eksperimentiniai tyrimai, panaudojant testinius KU pavyzdžius iš KU testinių pavyzdžių bibliotekos TSPLIB. Gauti rezultatai patvirtina pasiūlytų modifikacijų pranašumą kitų ITP variantų atžvilgiu. / In this work, one of the heuristic algorithm – the iterated tabu search and its modifications are discussed. The work is organized as follows. Firstly, some basic definitions and preliminaries are given. Then, the iterated tabu search algoritm and its variants based on special type mutations are considered in more details. The ITS algorithms modifications were tested on the TSP instances from the TSP library TSPLIB. The results of this tests (experiments) are presented as well. The work is completed with the conclusions.

This diploma thesis deals with Ant Colony algorithms and their usage for solving Travelling Salesman Problems and Vehicle Routing Problems. These algorithms are metaheuristics offering new approach to solving NP-hard problems. Work begins with a description of the forementioned tasks including ways to tackle them. Next chapter analyses Ant Colony metaheuristic and its possible usage and variations. The most important part of the thesis is practical and is represented by application Ant Colony Optimization Framework. It is easily extensible application written in Java that is able to solve introduced problems. In conclusion this work presents analysis of solutions on test data.

Nowadays, when great emphasis is put on cost savings, transport optimization is necessary part of every company life in which transportation costs produce significant part. There are optimization methods and possibilities presented in this thesis. In the first chapter there are explained methods such as the travelling salesman problem, the vehicle routing problem, the multiple vehicle routing problem and the split delivery vehicle routing problem and then the reader gets to know the heuristics methods in the chapter two where description of the nearest neighbour method, Clarke-Wright method and split delivery heuristic is mentioned. In the last but one chapter author applies previous methods on concrete distribution arranged by Movianto Česká republika s.r.o. on 5th September, 2013. Based on gained outputs, analysis and comparison of results (including the original distribution) are provided in the fourth chapter. Obtained results of analysis lead to recommendation on how the company should plan its future distribution.

The thesis deals with application of models of routing problems on a real problem, beer distribution in Jesenicko region provided by Viden plus, a.s. The goal of the thesis is to optimize daily distributional routes for two vehicles with different capacities. Total distance has to be minimized respecting time and capacity limits. In case the optimal solution is not found, sub-optimal solution will be accepted. Solutions are calculated with use of the optimization software LINGO and some heuristic methods. Models of travelling salesman problem and vehicle routing problem are used to find the solutions. Results are compared to the current state of distributional routes in conclusion of the thesis.