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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

Object recognition and automatic selection in a Robotic Sorting Cell

Janse van Rensburg, Frederick Johannes 12 1900 (has links)
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2006. / This thesis relates to the development of an automated sorting cell as part of a flexible manufacturing line, with the use of object recognition. Algorithms for each of the individual subsections creating the cell, recognition, position calculation and robot integration were developed and tested. The Fourier descriptors object recognition technique is investigated and used. Invariance to scale, rotation or translation of the boundary of an object recognition. Stereoscopy with basic trigonometry is used to calculate the position of recognised objects, after which they are handled by a robot. Integration of the robot into the project environment is done with trigonometry as well as Euler angles. It is shown that a successful, automated sorting cell can be constructed with object recognition. The results show that reliable sorting can be done with available hardware and the algorithms development.
52

Utilising provenance to enhance social computation

Markovic, Milan January 2016 (has links)
Many online platforms employ networks of human workers to perform computational tasks that can be difficult for a machine to perform (e.g. recognising an object from an image). This approach can be referred to as social computation. However, systems that utilise social computation often suffer from a lack of transparency, which results in difficulties in the decision-making process (e.g. assessing reliability of outputs). This thesis investigates how the lack of transparency can be addressed by recording provenance, which includes descriptions of social computation workflows and their executions. In addition, it investigates the role of Semantic Web technologies in modelling and querying such provenance in order to support decision-making. Following analysis of several use-case scenarios, requirements for describing the provenance of a social computation are identified to provide the basis of the Social Computation Provenance model, SC-PROV. This model extends the W3C recommendation for modelling provenance on the Web (PROV) and the P-PLAN model for describing provenance of abstract workflows. To satisfy the identified provenance requirements, SC-PROV extends PROV and P-PLAN with a vocabulary for capturing social computation features such as social actors (e.g. workers and requesters), incentives (e.g. promises of monetary rewards received upon completion of a task), and conditions (e.g. constraints defining when an incentive should be awarded). The SC-PROV model is realised in an OWL ontology and used in a semantic annotation framework to capture the provenance of a simulated case study, which includes 46,665 diverse workflows. During the evaluation process, the SC-PROV vocabulary is used to construct provenance queries that support an example workflow selection metric based on trust assessments of various aspects of social computation workflows. The performance of the workflow selected by this metric is then evaluated against the performance of two control groups - one containing randomly selected workflows and the other containing workflows selected by a metric informed by provenance which lacks SCPROV descriptions. The examples described in this thesis establish the benefits of examining provenance as part of decision-making in the social computation domain, and illustrate the inability of current provenance models to fully support these processes. The evaluation of SC-PROV demonstrates its capabilities to produce provenance descriptions that extend to the social computation domain. The empirical evidence provided by the evaluation supports the conclusion that using SC-PROV enhances support for trust-based decision-making.
53

[en] QUANTUM-INSPIRED LINEAR GENETIC PROGRAMMING / [pt] PROGRAMAÇÃO GENÉTICA LINEAR COM INSPIRAÇÃO QUÂNTICA

DOUGLAS MOTA DIAS 26 May 2011 (has links)
[pt] A superioridade de desempenho dos algoritmos quânticos, em alguns problemas específicos, reside no uso direto de fenômenos da mecânica quântica para realizar operações com dados em computadores quânticos. Esta característica fez surgir uma nova abordagem, denominada Computação com Inspiração Quântica, cujo objetivo é criar algoritmos clássicos (executados em computadores clássicos) que tirem proveito de princípios da mecânica quântica para melhorar seu desempenho. Neste sentido, alguns algoritmos evolutivos com inspiração quântica tem sido propostos e aplicados com sucesso em problemas de otimização combinatória e numérica, apresentando desempenho superior àquele dos algoritmos evolutivos convencionais, quanto à melhoria da qualidade das soluções e à redução do número de avaliações necessárias para alcançá-las. Até o presente momento, no entanto, este novo paradigma de inspiração quântica ainda não havia sido aplicado à Programação Genética (PG), uma classe de algoritmos evolutivos que visa à síntese automática de programas de computador. Esta tese propõe, desenvolve e testa um novo modelo de algoritmo evolutivo com inspiração quântica, denominado Programação Genética Linear com Inspiração Quântica (PGLIQ), para a evolução de programas em código de máquina. A Programação Genética Linear é assim denominada porque cada um dos seus indivíduos é representado por uma lista de instruções (estruturas lineares), as quais são executadas sequencialmente. As contribuições deste trabalho são o estudo e a formulação inédita do uso do paradigma da inspiração quântica na síntese evolutiva de programas de computador. Uma das motivações para a opção pela evolução de programas em código de máquina é que esta é a abordagem de PG que, por oferecer a maior velocidade de execução, viabiliza experimentos em larga escala. O modelo proposto é inspirado em sistemas quânticos multiníveis e utiliza o qudit como unidade básica de informação quântica, o qual representa a superposição dos estados de um sistema deste tipo. O funcionamento do modelo se baseia em indivíduos quânticos, que representam a superposição de todos os programas do espaço de busca, cuja observação gera indivíduos clássicos e os programas (soluções). Nos testes são utilizados problemas de regressão simbólica e de classificação binária para se avaliar o desempenho da PGLIQ e compará-lo com o do modelo AIMGP (Automatic Induction of Machine Code by Genetic Programming), considerado atualmente o modelo de PG mais eficiente na evolução de código de máquina, conforme citado em inúmeras referências bibliográficas na área. Os resultados mostram que a Programação Genética Linear com Inspiração Quântica (PGLIQ) apresenta desempenho geral superior nestas classes de problemas, ao encontrar melhores soluções (menores erros) a partir de um número menor de avaliações, com a vantagem adicional de utilizar um número menor de parâmetros e operadores que o modelo de referência. Nos testes comparativos, o modelo mostra desempenho médio superior ao do modelo de referência para todos os estudos de caso, obtendo erros de 3 a 31% menores nos problemas de regressão simbólica, e de 36 a 39% nos problemas de classificação binária. Esta pesquisa conclui que o paradigma da inspiração quântica pode ser uma abordagem competitiva para se evoluir programas eficientemente, encorajando o aprimoramento e a extensão do modelo aqui apresentado, assim como a criação de outros modelos de programação genética com inspiração quântica. / [en] The superior performance of quantum algorithms in some specific problems lies in the direct use of quantum mechanics phenomena to perform operations with data on quantum computers. This feature has originated a new approach, named Quantum-Inspired Computing, whose goal is to create classic algorithms (running on classical computers) that take advantage of quantum mechanics principles to improve their performance. In this sense, some quantum-inspired evolutionary algorithms have been proposed and successfully applied in combinatorial and numerical optimization problems, presenting a superior performance to that of conventional evolutionary algorithms, by improving the quality of solutions and reducing the number of evaluations needed to achieve them. To date, however, this new paradigm of quantum inspiration had not yet been applied to Genetic Programming (GP), a class of evolutionary algorithms that aims the automatic synthesis of computer programs. This thesis proposes, develops and tests a novel model of quantum-inspired evolutionary algorithm named Quantum-Inspired Linear Genetic Programming (QILGP) for the evolution of machine code programs. Linear Genetic Programming is so named because each of its individuals is represented by a list of instructions (linear structures), which are sequentially executed. The contributions of this work are the study and formulation of the novel use of quantum inspiration paradigm on evolutionary synthesis of computer programs. One of the motivations for choosing by the evolution of machine code programs is because this is the GP approach that, by offering the highest speed of execution, makes feasible large-scale experiments. The proposed model is inspired on multi-level quantum systems and uses the qudit as the basic unit of quantum information, which represents the superposition of states of such a system. The model’s operation is based on quantum individuals, which represent a superposition of all programs of the search space, whose observation leads to classical individuals and programs (solutions). The tests use symbolic regression and binary classification problems to evaluate the performance of QILGP and compare it with the AIMGP model (Automatic Induction of Machine Code by Genetic Programming), which is currently considered the most efficient GP model to evolve machine code, as cited in numerous references in this field. The results show that Quantum-Inspired Linear Genetic Programming (QILGP) presents superior overall performance in these classes of problems, by achieving better solutions (smallest error) from a smaller number of evaluations, with the additional advantage of using a smaller number of parameters and operators that the reference model. In comparative tests, the model shows average performance higher than that of the reference model for all case studies, achieving errors 3-31% lower in the problems of symbolic regression, and 36-39% in the binary classification problems. This research concludes that the quantum inspiration paradigm can be a competitive approach to efficiently evolve programs, encouraging the improvement and extension of the model presented here, as well as the creation of other models of quantum-inspired genetic programming.
54

Reconhecimento de movimentos humanos utilizando um acelerômetro e inteligência computacional. / Human movements recognition using an accelerometer and computational intelligence.

Silva, Fernando Ginez da 19 November 2013 (has links)
Observa-se nos tempos atuais um crescente interesse e demanda por novas tecnologias de sensoriamento e interação. A monitoração, com o objetivo de reconhecimento de movimentos humanos, permite oferecer serviços personalizados em diferentes áreas, dentre elas a área de cuidados médicos. Essa monitoração pode ser realizada por meio de diferentes técnicas como o uso de câmeras de vídeo, instrumentação do ambiente onde o indivíduo habita, ou pelo uso de dispositivos pessoais acoplados ao corpo. Os dispositivos acoplados ao corpo apresentam vantagens como baixo custo, uso confortável, além de muitas vezes serem despercebidos pelo usuário, diminuindo a sensação de invasão de privacidade durante a monitoração. Além disso, o dispositivo sensor pode ser facilmente acoplado ao corpo pelo próprio usuário, tornando o seu uso efetivo. Deste modo, este trabalho apresenta o desenvolvimento de um sistema que emprega técnicas de inteligência computacional e um acelerômetro facilmente acoplado ao punho do usuário para efetuar, de maneira confortável e não invasiva, o reconhecimento de movimentos básicos da rotina de uma pessoa. Aplicando máquinas de vetores de suporte para classificar os sinais e a razão discriminante de Fisher para efetuar a seleção das características mais significativas, o sistema apresentou uma taxa de sucesso em torno de 93% no reconhecimento de movimentos básicos efetuados por indivíduos monitorados. O sistema apresenta potencialidade para ser integrado a um hardware embarcado de baixo custo, responsável pelo gerenciamento da aquisição dos dados e pelo encaminhamento das informações a um sistema de monitoramento ou armazenamento. As informações providas por este sistema podem ser destinadas à promoção da saúde e bem estar do indivíduo, bem como utilizadas em diagnósticos ou monitoramento remoto de pacientes em um ambiente de vida assistida. / Nowadays it is observed a growing interest and demand for new sensing technologies and interaction. Monitoring with the objective of recognizing human movements, allows us to offer personalized services in different areas, among them healthcare. This monitoring can be performed through the use of different techniques such as the use of video cameras, living environment instrumentation, or the use of personal devices attached to the body, also known as wearable devices. These wearable devices have some advantages such as low cost, comfortable to use, and are often unnoticed by the user, reducing the feeling of privacy invasion during the monitoring. In addition, the sensing device can be easily attached to the body by the user itself, making its use effective. Thus, this work presents the development of a system that uses computational intelligence techniques and an accelerometer which is easily attached to the users wrist to perform, in a comfortable and non-invasive manner, the recognition of basic movements of a persons routine. By applying support vector machines to classify the signals and Fishers discriminant ratio to select the most significant features, the system has shown a success rate of 93% in the recognition of basic movements performed by monitored individuals. The system has the potential to be integrated into a low-cost embedded hardware, which is responsible for managing the data acquisition and routing the movement data to a remote monitoring system or storage. The information provided by the system can be designed to promote the health and wellness of the individual, as well used in diagnostics or remote patient monitoring in an ambient assisted living (AAL).
55

Generating narratives: a pattern language

Unknown Date (has links)
In order to facilitate the development, discussion, and advancement of the relatively new subfield of Artificial Intelligence focused on generating narrative content, the author has developed a pattern language for generating narratives, along with a new categorization framework for narrative generation systems. An emphasis and focus is placed on generating the Fabula of the story (the ordered sequence of events that make up the plot). Approaches to narrative generation are classified into one of three categories, and a pattern is presented for each approach. Enhancement patterns that can be used in conjunction with one of the core patterns are also identified. In total, nine patterns are identified - three core narratology patterns, four Fabula patterns, and two extension patterns. These patterns will be very useful to software architects designing a new generation of narrative generation systems. / by Samuel Greene. / Thesis (M.S.C.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
56

Kicks and Maps A different Approach to Modeling Biological Systems

Unknown Date (has links)
Modeling a biological systems, is a cyclic process which involves constructing a model from current theory and beliefs and then validating that model against the data. If the data does not match, qualitatively or quantitatively then there may be a problem with either our beliefs or the current theory. At the same time directly finding a model from the existing data would make generalizing results difficult. A considerable difficultly in this process is how to specify the model in the first place. There is a need to be practice which accounts for the growing use of mathematical and statistical methods. However, as a systems becomes more complex, standard mathematical approaches may not be sufficient. In the field of ecology, the standard techniques involve discrete maps, and continuous models such as ODE's. The intent of this work is to present the mathematics necessary to study hybrids of these two models, then consider two case studies. In first case we con sider a coral reef with continuous change, except in the presence of hurricanes. The results of the data are compared quantitatively and qualitatively with simulation results. For the second case we consider a model for rabies with a periodic birth pulse. Here the analysis is qualitative as we demonstrate the existence of a strange attractor by looking at the intersections of the stable and unstable manifold for the saddle point generating the attractor. For both cases studies the introduction of a discrete event into a continuous system is done via a Dirac Distribution or Measure. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
57

Detecção de dano em estruturas via inteligência computacional e análise dinâmica / Structural damage detection by means of computational intelligence techniques and dynamic analysis

Villalba Morales, Jesús Daniel 29 November 2012 (has links)
Nesta tese doutoral estudam-se formas de resolver o problema de detecção de dano em estruturas a partir da aplicação de técnicas de inteligência computacional e da resposta dinâmica da estrutura. Duas opções para a formulação do problema são consideradas. Primeiro, um problema de otimização é estabelecido a partir da minimização da diferença entre os parâmetros dinâmicos experimentais da estrutura na condição com dano e aqueles calculados utilizando um modelo de elementos finitos que representa tal condição. Diferentes técnicas metaheurísticas (algoritmos genéticos, particle swarm optimization, evolução diferencial), algumas em versões com adaptação de parâmetros, são empregadas. Estuda-se, ainda, a formulação do problema de otimização como um com múltiplos objetivos. Uma nova forma de avaliar o desempenho de uma metodologia de detecção de dano é proposta, que está baseada na capacidade da metodologia para obter um nível determinado de exatidão no cálculo da extensão do dano e na presença de falso-negativos e falso-positivos nos resultados. Segundo, aplicam-se redes neurais para determinar o mapeamento entre os parâmetros dinâmicos experimentais da condição atual da estrutura e a extensão ou posição do dano nesta. Estruturas do tipo viga e treliça foram submetidas a diferentes cenários de dano com o intuito de determinar o desempenho das metodologias propostas. Resultados mostram a habilidade de técnicas de inteligência computacional para detecção de cenários de dano com uns poucos elementos danificados; porém não é possível garantir que as metodologias terão sucesso para o 100% dos casos. Recomenda-se a utilização de técnicas de busca local para melhorar a solução encontrada pelos algoritmos globais. Finalmente, observou-se que se requer da determinação da quantidade mínima de informação a ser utilizada, uma função objetivo adequada e uma alta qualidade nas medições para garantir uma detecção de dano confiável. / This research aims at studying how to solve the damage detection problem by using computational intelligence techniques and the dynamic response of the structure. Two different ways for formulating the solution to the problem are implemented. In first place, an optimization problem is formulated as the minimization of the difference between the experimental dynamic parameters for the current structure and those from a finite element model that represent the damaged condition. Several metaheuristics (genetic algorithms, particle swarm optimization and differential evolution) are used to solve the optimization problem, where most of them present adaptive configurations. The implication of a multi-objective approach is also studied. A new scheme to determine the algorithm´s performance is proposed, which computes three error indicators concerning differences between the real and computed damage extents and the presence of false-positives and false-negatives. In second place, artificial neural networks are used to determine the mapping between the experimental dynamic parameters and either the damage extension (quantification) or the damage position (localization). Different damage scenarios were simulated in beam and truss structures to verify the performance of the proposed methodologies. Results show the ability of computational intelligence techniques to detect damage scenarios with a few damaged elements; however, it is not possible to guarantee a 100% of success. It is suggested to use local search techniques to improve the solution found by the different proposed algorithms. Three main conclusions are the followings: i) it is necessary to determine the minimum quantity of modal data that permits guarantying a reliable damage detection, ii) objective functions plays a very important role to the success of the algorithms and iii) noise prejudice the damage identification process.
58

Which Way is It? Spatial Navigation and the Genetics of Head Direction Cells

Unknown Date (has links)
From locating a secure home, foraging for food, running away from predators, spatial navigation is an integral part of everyday life. Multiple brain regions work together to form a three-dimensional representation of our environment; specifically, place cells, grid cells, border cells & head direction cells are thought to interact and influence one another to form this cognitive map. Head direction (HD) cells fire as the animal moves through space, according to directional orientation of the animal’s head with respect to the laboratory reference frame, and are therefore considered to represent the directional sense. Interestingly, inactivation of head direction cell-containing brain regions has mixed consequences on spatial behavior. Current methods of identifying HD cells are limited to in vivo electrophysiological recordings in a dry-land environment. We first developed a dry-land version of the MWM in order to carry out behavioral-recording paired studies. Additionally, to learn about HD cells function we quantified expression of neuronal activation marker (c-Fos), and L-amino acid transporter 4 (Lat4) in neurons found within the HD cell dense anterodorsal thalamic nucleus (ADN) in mice after exploratory behavior in an open field, or forward unidirectional movement on a treadmill. We hypothesize that the degree to which ADN neurons are activated during exploratory behavior is influenced by the range of heading directions sampled. Additionally, we hypothesize that c-Fos and Lat4 are colocalized within ADN neurons following varying amounts of head direction exposure. Results indicate that following free locomotion of mice in an open field arena, which permitted access to 360° of heading, a greater number of ADN neurons express c-Fos protein compared to those exposed to a limited range of head directions during locomotion in a treadmill. These findings suggest that the degree of ADN neuronal activation was dependent upon the range of head directions sampled. We observed a high degree of colocalization of c-Fos and Lat4 within ADN suggesting that Lat4 may be a useful tool to manipulate neuronal activity of HD cells. Identifying genetic markers specific to ADN helps provide an essential understanding of the spatial navigation system, and supports development of therapies for cognitive disorders affecting navigation. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
59

Uso de sensibilidade à situação em redes oportunistas para intensificar a comunicação de dados em aplicações de sensoriamento urbano / Use of situation awareness in opportunistic networks to improve data communication of social sensing applications

Rolim, Carlos Oberdan January 2016 (has links)
Cidades Inteligentes são sistemas urbanos que usam as Tecnologias da Informação e Comunicação (TICs) para tornar a infraestrutura e os serviços públicos de uma cidade mais interativos, acessíveis e eficientes aos seus habitantes. Com isso, surge a necessidade de proporcionar novos tipos de serviços que busquem auxiliar na organização da cidade, no bem-estar das pessoas e auxiliem a melhorar a governança da cidade. Nesse contexto, o Sensoriamento Urbano é um paradigma emergente, situado no escopo de Cidades Inteligentes, que combina a ubiquidade de smartphones e de diferentes tipos de sensores para coletar dados que retratam diferentes aspectos da cidade. Um aspecto importante nesse processo de sensoriamento é a transmissão dos dados coletados para serem processados por um sistema centralizado remoto. Isso demanda uma ampla e constante cobertura de infraestrutura de rede de comunicação, fato que nem sempre é possível. As Redes Oportunistas surgem como uma alternativa complementar e inovadora para situações como essa, onde as aplicações precisam transmitir dados porém a infraestrutura de rede é intermitente ou mesmo inexistente. Entretanto, com o uso de Redes Oportunistas, as aplicações além de herdarem os seus benefícios também herdam os desafios existentes na área relacionados à tomada de decisão de encaminhamento das mensagens. Dessa forma, a presente tese busca responder ao questionamento de como intensificar a disseminação de conteúdo e o encaminhamento de mensagens em aplicações de Sensoriamento Urbano que fazem uso de Redes Oportunistas como paradigma complementar de comunicação. Para isso é proposto o Situs, um componente de software baseado em Redes Oportunistas que utiliza Sensibilidade à Situação com vistas à proatividade nas tomadas de decisões de roteamento para com isso intensificar a entrega de mensagens. Ele emprega Lógica Fuzzy para a compreensão da situação e uma rede neural chamada Echo State Network (ESN) para efetuar a projeção de situações. Os resultados experimentais demonstraram que a sua performance supera algumas das principais iniciativas existentes na literatura. Por fim, pode-se concluir que ele é capaz de preencher as lacunas do estado da arte apresentadas durante o desenvolvimento da tese sendo capaz de proporcionar um comportamento proativo com o uso de Sensibilidade à Situação. / Smart cities are urban systems that uses Information and Communication Technologies (ICTs) to make infrastructure and public services in a more interactive, accessible and efficient city to its inhabitants. With this comes the need to provide new types of services that seeks to assist in the organization of the city, the well-being of people and assist to improve the governance of the city. In this context, urban sensing is an emerging paradigm, sited in the Smart Cities scope, combining the ubiquity of smartphones with the capability of measuring o sensors to collect data that depict different aspects of the city. This ecosystem consists of different types of mobile and fixed devices orchestrated by a computational architecture that encompass the full sensing process. An important aspect of this process is the transmission of data collected for processing by a remote central system. This requires a broad and constant coverage of communication network infrastructure, a fact that is not always possible. The Opportunistic Networks emerge as an innovative and complementary alternative for situations like this where the applications needs to transmit data but the network infrastructure is intermittent or unavailable. However, using Opportunistic Networks, applications as well as inherit its benefits also inherit the existing challenges in the area related to decision-making of messages forwarding. Thus, this thesis seeks to answer the question of how to improve the dissemination of content and message routing of urban sensing applications that makes use of Opportunistic networks as complementary communication paradigm. Therefore, it proposes Situs, a software component based on Opportunistic Networks that uses Situation Awareness towards a proactivity in making routing decisions. For such task, it applies fuzzy logic for situation comprehension and a king of neural network called Echo State Network (ESN) for situation projection. The results of the experiments showed that their performance outperforms some existent initiatives in literature. Finally, we argue it fullfills the gaps of state of art presented in this thesis and could provide a proactive behaviour with usage of situation awareness.
60

Modelo de avaliação de risco para predição de preços de carne bovina utilizando inteligência computacional / Model of evaluation of risk for prediction of prices in the beef chain by using computational intelligence

Lemes, Luciene Rose 08 August 2014 (has links)
A relação entre o preço futuro e o preço a vista é um fator que requer muita atenção e planejamento das atividades de comercialização agropecuária. As previsões de preços permitem fornecer a redução das incertezas dentro do mercado de carne bovina auxiliando na determinação da quantidade a ser produzida bem como no estabelecimento de políticas governamentais apropriadas e sustentáveis. Este trabalho tem como objetivo definir um modelo matemático capaz de predizer os preços de carne bovina usando inteligência computacional a partir da análise do ARIMA, Análise de Risco e Redes Neurais Artificiais, identificando aspectos quantitativos relacionados à lógica da decisão na formação do preço de venda, utilizando-se de séries temporais, a fim de explorar as correlações que impactam com maior frequência no preço de venda de carne bovina, por entender que este conhecimento pode aperfeiçoar os instrumentos de avaliação no processo de tomada decisão. A pesquisa caracteriza-se como descritiva, explicativa e quantitativa pois busca-se identificar fatores determinantes para a ocorrência dos fenômenos observados nas séries temporais de preço do boi gordo, traduzindo-se em números as informações classificadas e analisadas com o uso de técnicas estatísticas. Neste estudo foi utilizado a metodologia de séries temporais, aplicada à série histórica de preços do Boi Gordo no período de 23 de julho de 1997 a 18 de fevereiro de 2013, obtida junto ao Centro de Estudos Avançados em Economia Aplicada (CEPEA) da ESALQ/USP/Piracicaba. Estes dados representam o indicador de preço do Boi Gordo ESALQ/BM&F/BOVESPA utilizado como referencial para as negociações de compra e venda de contratos futuros. Os resultados demonstram a eficiência dos modelos propostos para a simulação e instrumentalização, ou seja, permitem avaliar o comportamento linear e não linear do modelo como ferramenta para a geração de informações e redução dos riscos que contribuirá para reduzir a subjetividade no processo de tomada de decisão. / The relationship between the future price and the cash down price of beef is a factor that requires much attention and planning in agricultural market activities. Price previews help to reduce uncertainties in the beef market and to assist in the determination of the quantity of beef to be produced as well as in the establishment of proper and sustainable governmental policies. This work aims to establish a mathematical model capable of predicting the price of beef using computational intelligence from the ARIMA analysis, Risk Analysis and Artificial Neural Network,by identifying the quantitative aspects related to the logic of decision in the formation of selling prices. This is done by using temporal series in order to explore the correlations that impact with greater frequency on the selling price of beef meat. Knowledge thus produced could improve the assessment instruments in the process of decision making. This research is characterized as descriptive, explanatory and quantitative because it intends to identify the determining factors for the occurrence of the observed phenomena in the time series of livestock prices where the classified and analyzed data result in numbers by the use of statistical techniques. The time series methodology was used. The historical series of livestock prices in the period from July 23rd 1997 to February 18th 2013 was obtained in the Center for Advanced Studies in Applied Economics (CEPEA) from ESALQ/USP/Piracicaba. This represents the livestock price indicator ESALQ/BM&F/BOVESPA that is used as a reference for the negotiations of purchase and sale in future contracts. The results show the effectiveness of the proposed models for simulation and orchestration, that is, they allow assessment of linear and non-linear behavior of the model as a tool for the generation of data and risk reductions that will contribute to less subjectivity in the decision-making process.

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