Nesse trabalho utilizou-se o reator anaeróbio horizontal de leito fixo (RAHLF) para produção de ácidos graxos voláteis (AGVs). O reator, com volume total de 2,38 litros, foi preenchido com partículas de argila expandida e alimentado com substrato sintético à base de glicose. Com concentração de glicose de 2000 mg/L, sem adição de alcalinizante e com tempo de detenção hidráulica (TDH) de 2 horas, houve produção de ácidos acético, butírico e propiônico. Com a variação do (TDH) de 2 horas para 0,5 hora, em condições idênticas, houve redução da produção do ácido butírico. Na segunda condição testada, em que a concentração da glicose foi 4000 mg/L, a concentração dos três ácidos aumentou, além de ser produzido o ácido capróico. Nas três últimas experimentações, com a glicose a 2000 mg/L e alcalinizada com bicarbonato de sódio, nas concentrações de 0,1000 e 2000 mg/L e TDH em 0,5 hora, as produções do ácido acético e propiônico aumentaram, enquanto que houve diminuição da produção dos ácidos butírico e capróico. A extração dos AGVs foi realizada em coluna de 320 mL de leito, com resina de troca iônica Dowex Marathon A - tipo aniônica base forte de amina quaternária em gel de divinil benzeno-estireno como matriz. O primeiro sistema extratante testado, foi com a resina condicionada na forma \'CL POT. -\' e a eluição foi feita com solução de \'NA\'\'CL\' em várias concentrações. Os percolados apresentaram alto teor de cloreto, inconveniente para as recuperações dos AGVs ou para o seu descarte no ambiente. O sistema testado com a resina condicionada na forma \'OH POT.-\' e a eluição com solução de \'NA\'\'OH\', em pH 13,5, demonstrou ser viável para a extração e concentração dos AGVs, com os fatores de concentração acima de 25, além de 80% do volume do percolado da fixação ser adequado para a devolução ao ambiente. No último teste o sistema utilizado foi o mesmo, com a alimentação apresentando a relação AVTs : sulfato de 1:1,27 e procurou-se fixar a máxima quantidade de AVTs. A eluição foi com solução de \'NA\'\'OH\' em três diferentes valores de pH: 12, 12,5 e 13. A presença do sulfato, nessa relação, dificultou a fixação dos AVs e, na eluição, competiu com os AVs, resultando em baixos fatores de concentração entre 2 e 3. Um volume de 47% do percolado da fixação e outro, de 29% da eluição, apresentou qualidade para o descarte. Na extração com solvente foram testados dois extratantes, a Alamina 336 (tri-octil/decil amina) e a Alamina 304-1 (tri-n-dodecilamina). O melhor sistema extratante, de solução de AVs impurificada com alto teor de sulfato, foi com a Alamina 336 condicionada com ácido nítrico. Entretanto, o consumo do ácido é alto o suficiente para inviabilizar economicamente a extração. Extração em sistema com baixo teor em sulfato e pH igual a 4,0 demonstrou ser técnicamente viável. Todavia, os valores da DQO residual nos refinados aquosos de todos os sistemas impossibilitam a devolução direta ao ambiente. / This work used the horizontal-flow anaerobic immobilized biomass (HAIB) reactor in order to produce volatile fatty acids (VFAs). The reactor, filled up with expanded clay particles, had a total volume of 2,38 liters and was fed with glucose based synthetic substrate. Production of acetic, butyric, and propionic acids occurred at an influent glucose concentration of 2000 mg/L without any addition of buffer agent and at a hydraulic retention time (HRT) of 2 hours. A reduction in butyric acid production occurred with the decrease of the HRT from 2 to 0,5 hours, with the reactor operating in identical conditions. In a second test condition, where the influent glucose concentration was increased to 4000 mg/L, the production of the three acids increased, beside the production of caproic acid. In the last three experiments, with influent glucose concentration at 2000 mg/L and buffered with sodium bicarbonate at concentrations of 0,1000 e 2000 mg/L and HRT of 0,5 hours, the production of acetic and propionic acids increased, whereas the production of butyric and caproic acids decreased. VFA extraction was accomplished in a 320 mL bed containing the ionic exchange resin Dowex Marathon A - strong base anionic type of quaternary amine in gel of benzene-styrene divinyl as matrix. The first extractant system was tested with the resin conditioned as \'C L POT.-\' and the elution was done with a solution of \'NA\'\'CL\' at different concentrations. The percolates presented high chloride concentration, which is inconvenient for the recovery of VFA or their release to the environment. On the other hand, the system with resin conditioned as \'OH POT.-\' and the elution with a solution of \'NA\'\'OH\' at pH 13,5 showed to be a viable option for the extraction and concentration of VFA with concentration factors above 25. In addition, the 80% of the volume of the fixation percolate is suitable for the devolution into the environment. The same system was used in the last test, however with the feeding at total volatile acids (TVA): sulfate ratios of 1:1,27 trying to fix the maximal amount of TVAs. The elution was done with \'NA\'\'OH\' at three different pH values: 12, 12,5 and 13. The presence of sulfate at this ration hampered the fixation of the volatile acids (VA) and during the elution competed with the VA, resulting in low concentration factors between 2 and 3. The volume of 47% of the fixation percolate and the volume of 29% of the elution presented good quality for discharge. Two extractants were tested in the extraction tests with solvents: Alamine 336 (tri-octyl/decyl amine) and the Alamine 304-1 (tri-n-dodecylamine). The best extractant system for the VA contaminated with high concentrations of sulfate was the Alamine 336 conditioned with nitric acid. The consumption of acid, however, was high enough to make the extraction economically unfeasible. On the other hand, extractions in systems with low sulfate concentrations and pH of 4 showed to be technically feasible, even though the residual chemical oxygen demand (COD) in the aqueous refined of all systems was too high for their direct devolution to the environment.

PurposeThe purpose of this study is to focus on the challenges with the implementation of technical solutions for automation of warehouse operations for the movement and tracking of goods. Additionally, the focus is on the similarities and differences between the identified challenges in theory and practice. MethodologyThis study employs a qualitative research strategy with a cross-sectional research design. A qualitative analysis of the challenges for the automation of warehouse operations is done, with the help of semi-structured interviews of 9 different companies.TheoryThe theory chapter starts with an introduction of warehouse management systems (WMS) and the differentiation between the main and supportive warehouse processes, whereby the focus is drawn on the supportive processes. The supportive processes are differentiated into the movement and tracking of goods. For the movement of goods automated guided vehicles (AGVs), Automated forklifts and Automated conveyor systems are analyzed. For the tracking of goods Barcodes, QR-Codes and RFID technology is examined. These two areas are also analyzed regarding their identified challenges. AnalysisThe analysis is based on the identification of the challenges from theory and empirical data for the tracking and movement of goods within a warehouse. Therefore, the empirical perceived challenges are processed and merged together. Afterwards, the theoretical and empirical identified challenges are compared for each of the technical solutions for automation for the movement and tracking of goods. Additionally, a comparison between the degrees of importance of the perceived challenges is drawn.Conclusion Technical solutions for automation for the movement and tracking of goods perceived in theory and practice are analyzed in this thesis. The conclusion of this study is that there are differences and similarities between the challenges for the movement and tracking of goods. Regarding the movement of goods, theory is more directed to see challenges after the implementation in contrast to the focus of practice on the pre-implementation challenges. For the tracking of goods, the perceived challenges in practice are more about the usage and not as technical oriented as the theory.

This thesis is concerned with the robots' motion planning problem. In particular it is focused on the path planning and motion planning for Autonomously Guided Vehicles (AGVs) in well-structured, two-dimensional static and dynamic environments. Two algorithms are proposed for solving the aforementioned problems. The first algorithm establishes the shortest collision-semi-free path for an AGV from its start point to its goal point, in a two-dimensional static environment populated by simple polygonal obstacles. This algorithm constructs and searches a reduced visibility graph, within the AGV's configuration space, using heuristic information about the problem domain. The second algorithm establishes the time minimal collision-semi-free motion for an AGV, from its start point to is goal point, in a two-dimensional dynamic environment populated by simple polygonal obstacles. This algorithm considers the AGV's spacetime configuration space, thus reducing the dynamic motion planning problem to the static path planning problem. A reduced visibility graph is then constructed and searched using information about the problem domain, in the AGV's space-time configuration space in order to establish the time-minimal motion between the AGV's start and goal configurations. The latter algorithm is extended to solve more complicated instances of the dynamic motion planning problem, where the AGV's environment is populated by obstacles, which change their size as well as their position over time and obstacles, which have piecewise linear motion. The proposed algorithms can be used to efficiently and safely navigate AGVs in well structured environments. For example, for the navigation of an AGV, in industrial environments, where it operates as part of the manufacturing process or in chemical and nuclear plants, where the hostile environment is inaccessible to humans. The main contributions in this thesis are, the systematic study of the V*GRAPH algorithm and identification of its methodic and algorithmic deficiencies; recommendation of corrections and further improvements on the V* GRAPH algorithm, which in turn lead to the proposition of the V*MECHA algorithm for robot path planning; proposition of the D*MECHA algorithm for motion planning in dynamic environments; extension to the D*MECHA algorithm to solve more complicated instances of the dynamic robot motion planning problem; discussion of formal proofs of the proposed algorithms' correctness and optimality and critical comparisons with existing similar algorithms for solving the motion planning problem.

Submitted by Izabel Franco (izabel-franco@ufscar.br) on 2016-10-05T12:59:30Z No. of bitstreams: 1 TeseVFC.pdf: 9165002 bytes, checksum: bb98f82058344c51fda9b34979b8a524 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-20T18:15:16Z (GMT) No. of bitstreams: 1 TeseVFC.pdf: 9165002 bytes, checksum: bb98f82058344c51fda9b34979b8a524 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-20T18:15:22Z (GMT) No. of bitstreams: 1 TeseVFC.pdf: 9165002 bytes, checksum: bb98f82058344c51fda9b34979b8a524 (MD5) / Made available in DSpace on 2016-10-20T18:15:28Z (GMT). No. of bitstreams: 1 TeseVFC.pdf: 9165002 bytes, checksum: bb98f82058344c51fda9b34979b8a524 (MD5) Previous issue date: 2016-05-02 / In recent years, manufacturers are increasingly applying automation techniques with the aim of increase their efficiency to remain competitive. The material handling is an essential activity in any process of production and its effectiveness has severe impacts on production costs. Systems of automated guided vehicles (AGVs) have become an important strategic tool for factories and automated warehouses. In a very competitive business scenario, they can increase productivity and reduce costs. The management of these AGVs is the key to a transport system that ensures the improvements envisioned by the industry. One of the main problems encountered in the management of AGVs is the dispatch decision. This paper proposes a vehicles dispatch model based on a fuzzy cascade system for consideration of multiple attributes of the factory and a structure based on state space that enables the extraction of information of future states of the industrial production system. The objective is to reduce makespan and tardiness values of the production system. Two factory scenarios are simulated and tests are performed of the model and five other methods of dispatch. A statistical validation is realized of the results in which corroborates with 97% confidence the hypotheses of the work. / Nos últimos anos, as indústrias vêm cada vez mais aplicando técnicas de automação com o objetivo de aumentar sua eficiência para manterem-se competitivas. O manuseio de materiais é uma atividade essencial em qualquer processo de produção e sua eficácia tem impactos severos sobre os custos de produção. Sistemas de veículos autoguiados (AGVs) tornaram-se uma ferramenta estratégica importante para fábricas e armazéns automatizados. Em um cenário de negócio muito competitivo, eles podem aumentar a produtividade e reduzir os custos. O gerenciamento desses AGVs é a chave para um sistema de transporte que garanta as melhorias vislumbradas pelas indústrias. Um dos principais problemas encontrados no gerenciamento dos AGVs é a decisão de despacho. Esse trabalho propõe um modelo de despacho de veículos baseado em um sistema fuzzy cascata para ponderação de múltiplos atributos da fábrica e em uma estrutura baseada em espaço de estados que permita a extração de informações de estados futuros do sistema de produção fabril. O objetivo é reduzir valores de makespan e tardiness do sistema de produção. Dois cenários de fábrica são simulados e são realizados testes do modelo proposto e cinco outros métodos de despachos. É realizada uma validação estatística dos resultados em que se corrobora com 97% de confiança as hipóteses do trabalho

This thesis is based on the work carried out in the field of safety systems for Autonomous Guided Vehicles(AGV). With autonomous vehicles being more prominent today, safe traversing of these is a major concern. The same is true for AGVs working in industry environment like forklift trucks etc. Our work applies to industrial robots. The method described here is developed by closely following an algorithm developed for safe traversing of a robot using a warning field. The report describes the literature review with work related to the safe traversing, path planning and collision avoidance in robots. The next part is dedicated to describing the methodology of implementation of the Adaptive Warning Field Method and the Dynamic Window Approach. The evaluation of the Adaptive Warning Method with the previous developed Warning Field Methods is done and test cases are designed to test the working of the designed method. Vrep simulation environment and Industrial data is used to run a simulation of the robot using the method developed in this work. We find that the method performs better compared to the previous methods in the designed scenarios. Lastly we conclude the report with the future work that can be carried out to improve and extend the algorithm.

Made available in DSpace on 2016-06-02T19:05:50Z (GMT). No. of bitstreams: 1 3678.pdf: 5394148 bytes, checksum: 4abd3e7ce4acac9d5890eae3620c06d3 (MD5) Previous issue date: 2011-06-14 / Financiadora de Estudos e Projetos / In recent years, most companies apply techniques of industrial automation with the goal of increasing its efficiency. Increasingly Automated Guided Vehicles (AGVs) are used to transport work in factories and warehouses. The management of these AGV is the key to an efficient transport system. One of the main problems encountered in the management of AGV is the dispatching decision. This work proposes a method of dispatching of AGV with the ability to optimize the performance of flexible manufacturing systems (FMS) in real time. In the dispatching deciding can be chosen to optimize two objectives: makespan or tardiness. When the goal is to optimize the makespan are evaluated variables: distance, number of nodes, the input buffer and output buffer of the workstation. When the goal is to optimize the tardiness are evaluated variables: distance, number of nodes, task chaining, date of delivery. In both cases are also considered the time of the AGVs and the processing times of the workstations, so you can anticipate some decision-making. To perform the tests we used the softwares: Matlab, CPNtools and Automod, which allow simulations of how the method works dispatching AGVs before the method is implemented in factories. Based on the tests, we analyzed the improvement in makespan and tardiness compared to other studies, but also the flexibility of the method in which it is possible to exchange goals in operating time. / Nos últimos anos, mais empresas aplicam técnicas de automação industrial com o objetivo de aumentar sua eficiência. Cada vez mais Veículos Auto Guiados (AGVs) são usados para tarefa de transporte em indústrias e armazéns. O gerenciamento desses AGVs é a chave para um sistema de transporte eficiente. Um dos principais problemas encontrados no gerenciamento dos AGVs é a decisão de despacho. Esse trabalho propõe um método de despacho de AGV com capacidade de otimizar o desempenho de Sistemas Flexíveis de Manufatura (FMS) em tempo real. Na tomada de decisão do despacho podem ser escolhidos dois objetivos para otimização: makespan ou tardiness. Quando o objetivo é otimizar o makespan são avaliadas as variáveis: distância, número de nós, buffer de entrada e buffer de saída das estações de trabalho. Quando o objetivo é otimizar o tardiness são avaliadas as variáveis: distância, número de nós, encadeamento de tarefas, data de entrega do produto. Em ambos os casos também são considerados os tempos dos AGVs e os tempos de processamento das estações de trabalho, para que seja possível adiantar algumas tomadas de decisões. Para realizar os testes foram usados os softwares MatLab, CPNtools e Automod, os quais permitem que simulações do funcionamento do método de despacho de AGVs antes que o método seja implementado em fábricas. Com base nos testes realizados, analisou-se as melhoras no makespan e tardiness em comparação com outros trabalhos, como também a flexibilidade do método no qual é possível a troca de objetivos em tempo de operação.