Made available in DSpace on 2015-05-08T14:57:17Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3123506 bytes, checksum: 243f3e4e3248e64433561a39646c765d (MD5) Previous issue date: 2013-08-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work, an Artificial-Immune-System based anomaly detection system applied to Water Supply System is presented. At normal working, the pressure level into the system is controlled by a Fuzzy Control System. As the Water Supply System is composed of pressure sensors, valves, pumps, and other devices, faults in these devices causing abnormal disturbances can occur. An algorithm of Artificial-Immune-System, namely, the Negative Selection Algorithm, is the base of the proposed anomaly detection system. The Negative Selection Algorithm verifies abnormal system conditions based on the normal system conditions. Experimental results show that the proposed system is effective in order to detect anomaly. / Neste trabalho é apresentado um método de detecção automática de falhas, baseado em Sistemas Imunológicos Artificias, aplicado em um sistema de abastecimento de água. Este processo utiliza um Sistema de Controle Fuzzy para manter o nível de pressão estabilizado em seu princípio de operação normal do sistema. Esta plataforma de abastecimento de água é composta por sensores de pressão, válvulas, bombas e outros dispositivos. Falhas nos componentes que compõem a plataforma poderão ocorrer causando perturbações em seu funcionamento. Um algoritmo, extraído dos Sistemas Imunológicos Artificiais, denominado de Algoritmo de Seleção Negativa, é a base de detecção de falhas proposto neste trabalho. Este algoritmo verifica condições de operação anormais baseado nas condições de funcionamento normal do sistema. Resultados das simulações e experimentos acerca da utilização deste algoritmo foram obtidos comprovando a eficiência dessa técnica.

Orientador: Celso de Almeida, Rodrigo Pereira Ramos / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-08T10:36:25Z (GMT). No. of bitstreams: 1 Britto_PauloMarceloPerezRodriguesde_M.pdf: 4780408 bytes, checksum: c3b152e041128b5d94429d8b87c0068c (MD5) Previous issue date: 2006 / Resumo: O desempenho de sistemas de comunicações sem fio que utilizam técnicas de espalhamento espectral e múltiplo acesso por divisão de código (CDMA) é limitado pela interferência. Nesta dissertação, analisamos o desempenho de um algoritmo de seleção de seqüências de espalhamento de comprimento fixo, que busca a minimização dos efeitos de interferência em sistemas CDMA operando em canais com desvanecimento seletivo em freqüência e possuindo células adjacentes interferentes. Analisamos o desempenho deste sistema no qual o espalhamento espectral é feito usando duas seqüências: seqüências do usuário e seqüências identificadoras de células. Dentre as seqüências analisadas, podemos citar as Walsh, a Gold, as de comprimento máximo e também um tipo de seqüência de espalhamento baseado nas seqüências de comprimento máximo / Abstract: The performance of wireless communication systems using spread spectrum techniques and code division multiple access (CDMA) is interference-limited. In this dissertation, we evaluate the performance of a selection algorithm for fixed-length spreading sequences, aimed on minimizing the interference effects in CDMA systems operating in frequency selective fading channels and having adjacent interfering cells. We check the performance of this system where the spread spectrum operation is performed using two sequences: user sequences and cell identification sequences. Among the sequences considered, we use Walsh, Gold, maximum length and a type of spreading sequence based on the maximum length class / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica

Wireless mobile ad-hoc networks consist of a collection of peer mobile nodes that form a network and are capable of communicating with each other without help from stationary infrastructure such as access points. The availability of low-cost, com-modity network interface cards (NICs) has made the IEEE 802.11 medium access control (MAC) protocol the de facto MAC protocol for wireless mobile ad-hoc net-works, even though it is not optimal. The IEEE 802.11 MAC protocol is designed to have stations share a single channel in a given network. However, many of the IEEE 802.11 physical (PHY) layer specifications define multiple channels and allow the simultaneous, non-interfering use of some of these channels. Therefore, multiple communications can occur at the same time, offering the opportunity to increase the effective network capacity. We present an innovative routing protocol that utilizes multiple channels to im-prove the performance of wireless ad-hoc networks. The basic idea of the protocol is to use multiple channels so that multiple useful transmissions can occur simultane-ously, thus increasing network capacity. The proposed scheme requires minor changes to existing proactive ad-hoc routing protocols and no modifications to the current IEEE 802.11 MAC protocol. To reduce inefficiencies due to periodic updates in the proactive routing protocols, the proposed scheme divides the network layer into control and data planes. Nodes send routing updates using the control channel and user packets using the data channel. To demonstrate the multi-channel routing scheme, we extend the Destination-Sequenced Distance-Vector (DSDV), Open Shortest Path First-Minimal Connected Dominating Set (OSPF-MCDS), and Optimized Link State Routing (OLSR) protocol to multiple channel (MC) versions, denoted as DSDV-MC, OSPF-MCDS-MC, and OLSR-MC, respectively. Simulation results for DSDV-MC, OSPF-MCDS-MC, and OLSR-MC are presented and experimental results for OLSR-MC are presented. Simulation results indicate that DSDV-MC and OSPF-MCDS-MC effectively exploit multiple channels to improve network capacity. Goodput, the throughput consider-ing only useful error-free packets, increases with an increased number of available channels as the number of nodes and network load increase in both single-hop and multiple-hop networks. Experimental results with OLSR-MC also support that the proposed scheme increases network capacity without modification to the MAC proto-col in a real implementation. Although simulation and experimental results show that proposed scheme im-proves network capacity by exploiting multiple channels, problems exist with channel distribution. We introduce a new metric, the Channel Distribution Index (CDI) to in-vestigate these issues. The CDI indicates the fairness of the channel distribution. We identify the channel convergence problem, where a particular channel is over-utilized, and propose a channel reallocation scheme to mitigate the impact of the channel convergence problem using the CDI. / Ph. D.

The Mobile Electronic Dispensary System (MEDS) is an indoor medical dispensary system where robots locate and travel to patients within a grid in order to deliver medication or other medical supplies based on a predefined schedule. For older people or individuals with physical or mental disabilities, it is important to ensure that medications are taken as prescribed. Missing or mixing dosages can cause unwanted and even harmful consequences. As individuals grow older or battle disabilities, it is expected that adhering to their medicine regimen will be a daily challenge without the assistance of a fulltime caregiver. Therefore, to assist individuals in maintaining their independence, MEDS ensures the proper medicine is dispensed to the patient at the prescribed time and dosage. At the core of MEDS is a scheduler that maintains the medicines to be dispensed, including the times and dosages. Once a scheduled time arrives to deliver medicine to a patient, MEDS instructs the appropriate robot to wake up, locate the patient within a defined grid, and then travel to the patient and deliver the medicine. Upon receiving the delivery, the patient will accept the medicine physically and then update their mobile device, informing MEDS that the medicine was successfully delivered. At this time, the robot will return to its home base within the grid. The patients are within the confines of a building where GPS is not a viable solution to track items to pinpoint accuracy. Therefore, an indoor location based system with beacons and listeners are required in order to define a grid and enable robots to locate and travel to the patient. This paper defines and details the programs, database, algorithms, and hardware of MEDS using the Cricket Indoor Location System and iRobot Creates. / text

La part dû au test dans le coût de conception et de fabrication des circuits intégrés ne cesse de croître, d'où la nécessité d'optimiser cette étape devenue incontournable. Dans cette thèse, de nouvelles méthodes d'ordonnancement et de réduction du nombre de tests à effectuer sont proposées. La solution est un ordre des tests permettant de détecter au plus tôt les circuits défectueux, qui pourra aussi être utilisé pour éliminer les tests redondants. Ces méthodes de test sont basées sur la modélisation statistique du circuit sous test. Cette modélisation inclus plusieurs modèles paramétriques et non paramétrique permettant de s'adapté à tous les types de circuit. Une fois le modèle validé, les méthodes de test proposées génèrent un grand échantillon contenant des circuits défectueux. Ces derniers permettent une meilleure estimation des métriques de test, en particulier le taux de défauts. Sur la base de cette erreur, un ordonnancement des tests est construit en maximisant la détection des circuits défectueux au plus tôt. Avec peu de tests, la méthode de sélection et d'évaluation est utilisée pour obtenir l'ordre optimal des tests. Toutefois, avec des circuits contenant un grand nombre de tests, des heuristiques comme la méthode de décomposition, les algorithmes génétiques ou les méthodes de la recherche flottante sont utilisées pour approcher la solution optimale. / The share of test in the cost of design and manufacture of integrated circuits continues to grow, hence the need to optimize this step. In this thesis, new methods of test scheduling and reducing the number of tests are proposed. The solution is a sequence of tests for early identification of faulty circuits, which can also be used to eliminate redundant tests. These test methods are based on statistical modeling of the circuit under test. This model included several parametric and non-parametric models to adapt to all types of circuit. Once the model is validated, the suggested test methods generate a large sample containing defective circuits. These allow a better estimation of test metrics, particularly the defect level. Based on this error, a test scheduling is constructed by maximizing the detection of faulty circuits. With few tests, the Branch and Bound method is used to obtain the optimal order of tests. However, with circuits containing a large number of tests, heuristics such as decomposition method, genetic algorithms or floating search methods are used to approach the optimal solution.

Made available in DSpace on 2016-03-15T19:37:43Z (GMT). No. of bitstreams: 1 Luiz Antonio Carraro.pdf: 1226702 bytes, checksum: 3cef29694a4e26f233b0aae16da69cf0 (MD5) Previous issue date: 2012-02-16 / Universidade Presbiteriana Mackenzie / A container is a broadly used solution for the cargo storage to be transported between ports, playing a central role in international trade. Consequently, ships grew in size in order to maximize their container transportation capacity in each trip. Due to increasing demand, container terminals face the challenges of increasing their service capacity and optimizing the loading and unloading time of ships. Optimization problems, such as these, often present features that make it impossible to obtain closed analytical solutions, requiring iterative search procedures in high-dimensional spaces, or subject to a combinatorial explosion of possible solutions. This dissertation presents the proposal of a novel meta-heuristic based on the Clonal Selection Algorithm, named MRC, to minimize the number of reshuffles in operations involving piles of containers. The performance of the proposed model was evaluated through simulations and results comparison with those obtained by algorithms from the literature under the same test conditions. The results obtained show that MRC is competitive in terms of minimizing the need of reshuffles, besides presenting a reduced processing time compared with models of similar performance. / A utilização de contêineres é uma solução amplamente adotada para o armazenamento da carga a ser transportada entre portos, tornando-se de grande importância no comércio internacional e, consequentemente, navios cresceram de tamanho com o objetivo de transportar a maior quantidade possível de contêineres em cada viagem. Devido à crescente demanda, terminais de contêineres enfrentam os desafios de aumentar a sua capacidade de atendimento e otimizar os tempos de carregamento e descarregamento de navios. Problemas de otimização como estes geralmente apresentam características que inviabilizam a obtenção de soluções analíticas fechadas, requerendo processos iterativos de busca em espaços de dimensão muitas vezes elevada, ou ainda sujeitos a explosão combinatória de possíveis soluções. Esta dissertação apresenta a proposta de uma meta-heurística bioinspirada baseada no Algoritmo de Seleção Clonal para a minimização de rearranjos em operações que envolvem pilhas de contêineres, denominado MRC. O desempenho do algoritmo foi avaliado por meio de simulações e comparação dos resultados com os obtidos por algoritmos da literatura sob as mesmas condições de teste. Os resultados obtidos permitem concluir que o MRC possui resultados competitivos em termos de minimização de rearranjos, além de apresentar um tempo de processamento reduzido quando comparado aos modelos tradicionalmente empregados na solução desse tipo de problema.

Orientador: Celso de Almeida / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-12T06:34:19Z (GMT). No. of bitstreams: 1 Mataveli_LuisOtavio_M.pdf: 877476 bytes, checksum: afc5fb9153e7311af03669d45d798a73 (MD5) Previous issue date: 2008 / Resumo: O desempenho dos sistemas de comunicação sem fio que utilizam a técnica de múltiplo acesso CDMA é limitado pela interferência. A proposição de um algoritmo de escolha de seqüências de espalhamento foi feita para buscar uma diminuição na interferência média do sistema. Nos padrões atuais, como CDMA2000 e WCDMA, não são definidos nenhum critério para escolha das seqüências. Por isso, nesta dissertação será analisado o desempenho do algoritmo de escolha de seqüências de espalhamento proposto anteriormente juntamente com o uso de códigos corretores de erro em canais com desvanecimento seletivo em freqüência. Será analisado o comportamento das seqüências Walsh, Gold e m-deslocadas. O algoritmo analisado apresenta bons resultados sem o uso de codificação, mas, como maneira de analisar um sistema mais próximo do real, serão utilizados os códigos convolucionais e turbo. Palavras-chave: Algoritmo de busca, sistemas CDMA, espalhamento espectral, códigos convolucionais, códigos turbo. / Abstract: The performance of wireless communication systems that use the multiple access code division technique, CDMA, is interference-limited. A sequence selection algorithm allows a reduction in the mean interference of the system. In the standards like CDMA2000 and WCDMA no algorithm is defined for choosing the sequences. For this reason, in this dissertation we evaluate the performance of the proposed spread sequences selection algorithm together with error correcting codes over frequency selective fading channels. It is analyzed the behavior of Walsh, Gold, and shifted-m sequences. The algorithm had shown good results without channel coding, but to analyze a system similar to a real one, convolutional and turbo codes are going to be used. Key words: Selection algorithm, CDMA systems, spread spectrum, convolutional codes, turbo codes. / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica

Le protocole MAC du standard IEEE 802.11p dédié aux réseaux véhiculaires interdit les transmissions simultanées dans une même zone de détection afin d’éviter d’éventuelles interférences entre les véhicules voisins. Cette interdiction entraîne un blocage temporaire de réception de données, ce qui diminue le débit global du réseau. Pour résoudre ce problème, nous proposons dans cette thèse une architecture cross-layer PHY/MAC basée sur un algorithme de sélection d’antennes émettrices et un protocole MAC dédié afin de réduire le blocage. Ce cross-layer permet au récepteur de choisir la meilleure combinaison d’antennes émettrices pour améliorer le débit utile normalisé de chaque lien V2V. L’algorithme est présenté avec une méthode de détection multi-utilisateurs. Cette méthode annule les interférences entre voisins et permet à plusieurs véhicules d’émettre des données simultanément. Le protocole MAC associé assure la coordination entre les véhicules durant les communications. Les résultats de simulation montrent une amélioration du débit utile normalisé du réseau en comparaison au standard actuel. Néanmoins, ces bonnes performances diminuent avec l’augmentation de la densité véhiculaire. Pour pallier à cette baisse, nous proposons de joindre à la première solution une nouvelle architecture crosslayer PHY/MAC. Cette architecture est basée sur un algorithme d’adaptation de la puissance émise en fonction de la densité de voisinage du récepteur. Elle est également accompagnée par un protocole MAC dédié. Les résultats de simulation montrent que cette solution permet à plus de véhicules de communiquer simultanément et ainsi améliore significativement le débit utile normalisé notamment dans les réseaux véhiculaires denses. / The MAC protocol IEEE 802.11p, dedicated to vehicular ad-hoc networks VANETs, prohibits simultaneous transmissions in the same detection area, in order to avoid interference between neighboring vehicles. This prohibition causes a temporary data reception blocking, which reduces the network throughput. To reduce this adverse impact, we propose in this thesis a cross-layer design PHY/MAC based on a transmit antennas selection algorithm jointly with a dedicated MAC protocol. This design allows receivers to select the best combination of transmit antennas to improve the throughput of each V2V link. The algorithm is presented with a multi-user detection method, which cancels neighbor’s interference and allows vehicles to transmit data simultaneously. The associated MAC protocol ensures the coordination between vehicles during the simultaneous transmission period. The simulation results show a significant network throughput improvement compared to the conventional case. However, this improvement is less important in dense VANETs. For this purpose, we propose to join a cross-layer design PHY/MAC based on a transmit power adaptation algorithm. This design allows transmitters to choice the adequate power level based on corresponding receivers density. The simulation results show that this solution allows more vehicles to communicate simultaneously and thus improves the network throughput, in particular in dense VANETs.

Two of the most important environmental challenges in the 21st century are to protect the quality of fresh water resources and to utilize renewable energy sources to lower greenhouse gas emissions. This study contributes to the solution of the first challenge by providing methodologies for optimal design of real-time water quality monitoring systems and interpretation of data supplied by the monitoring system to identify potential pollution sources in river networks. In this study, the optimal river water quality monitoring network design aspect of the overall monitoring program is addressed by a novel methodology for the analysis of this problem. In this analysis, the locations of sampling sites are determined such that the contaminant detection time is minimized for the river network while achieving maximum reliability for the monitoring system performance. The data collected from these monitoring stations can be used to identify contamination source locations. This study suggests a methodology that utilizes a classification routine which associates the observations on a contaminant spill with one or more of the candidate spill locations in the river network. This approach consists of a training step followed by a sequential elimination of the candidate spill locations which lead to the identification of potential spill locations. In order to contribute the solution of the second environmental challenge, this study suggests utilizing available excess energy in water distribution systems by providing a methodology for optimal design of energy recovery systems. The energy recovery in water distribution systems is possible by using micro hydroelectric turbines to harvest available excess energy inevitably produced to satisfy consumer demands and to maintain adequate pressures. In this study, an optimization approach for the design of energy recovery systems in water distribution networks is proposed. This methodology is based on finding the best locations for micro hydroelectric plants in the network to recover the excess energy. Due to the unsteady nature of flow in water distribution networks, the proposed methodology also determines optimum operation schedules for the micro turbines.