Energy harvesting from the rotating system has been an influential topic for researchers over the past several years. Yet, most of these harvesters are linear resonance-based harvesters whose output power drops dramatically under random excitations. This poses a serious problem because a lot of vibrations in rotating systems are stochastic. In this dissertation, a novel energy harvesting strategy for rotating systems was proposed by taking advantage of stochastic resonance. Stochastic resonance is referred to as a physical phenomenon that is manifest in nonlinear bistable systems whereby a weak periodic signal can be significantly amplified with the aid of inherent noise or vice versa. Stochastic resonance can thus be used to amplify the noisy and weak vibration motion. Through mathematical modeling, this dissertation shows that stochastic resonance is particularly favorable to energy harvesting in rotating systems. The conditions for stochastic resonance are satisfied by adding a nonlinear bistable energy harvester to the rotating system because whirl noise and periodic signalㄴ already coexist in the rotating environment. Both numerical and experimental results show that stochastic resonance energy harvester has higher power and wider bandwidth than linear harvesters under a rotating environment. The dissertation also investigates how stochastic resonance changes for the various types of excitation that occur in real-world applications. Under the non-gaussian noise, the stochastic resonance frequency is shifted larger value. Furthermore, the co-existence of the vibrational and stochastic resonance is observed depending on the periodic signal to noise ratio. The dissertation finally proposed two real applications of stochastic resonance energy harvesting. First, stochastic resonance energy harvester for oil drilling applications is presented. In the oil drilling environment, the periodic force in rotating shafts is biased, which can lower the efficacy of stochastic resonance. To solve the problem, an external magnet was placed above the bi-stable energy harvester to compensate for the biased periodic signal. Energy harvester for smart tires is also proposed. The passively tuned system is implemented in a rotating tire via centrifugal force. An inward-oriented rotating beam is used to induce bistability via the centrifugal acceleration of the tire. The results show that larger power output and wider bandwidth can be obtained by applying the proposed harvesting strategy to the rotating system. / Doctor of Philosophy / In this dissertation, a novel energy harvesting strategy for rotating systems was proposed by taking advantage of stochastic resonance. Stochastic resonance is referred to as a physical phenomenon that is manifest in nonlinear bistable systems whereby a weak periodic signal can be significantly amplified with the aid of inherent noise or vice versa. Stochastic resonance can thus be used to amplify the noisy and weak vibration motion. Through mathematical modeling, this dissertation shows that stochastic resonance is particularly favorable to energy harvesting in rotating systems.Both numerical and experimental results show that stochastic resonance energy harvester has higher power and wider bandwidth than linear harvesters under a rotating environment. The dissertation also investigates how stochastic resonance changes for the various types of excitation that occur in real-world applications. The dissertation finally proposed two real applications of stochastic resonance energy harvesting. First, stochastic resonance energy harvester for oil drilling applications is presented. Energy harvester for smart tires is also proposed. The results show that larger power output and wider bandwidth can be obtained by applying the proposed harvesting strategy to the rotating system.

[pt] O aumento da complexidade dos SGBDs comerciais e a carga que suportam, além da crescente utilização destes por pessoal pouco familiarizado com a administração de bancos de dados, entre outras causas, sugerem a introdução de técnicas que automatizem o processo de sintonia de bancos de dados. A auto-sintonia (self-tuning) é uma tecnologia que permite criar sistemas adaptáveis que possam manter um bom desempenho, minimizando no possível a interação do administrador com o sistema. Este trabalho propõe uma abordagem para o ajuste automático dos parâmetros em um SGBD usando agentes de software. A tarefa de sintonia é tratada nesta pesquisa como um problema global, dado que alterações de um parâmetro podem se refletir em outros. Os detalhes da arquitetura, sua implementação e avaliação de funcionamento são também discutidos nesta dissertação. / [en] The increasing complexity of the commercial DBMSs as well the workload they manage, besides the fact that many users do not have deep knowledge about database administration, among other reasons, strongly suggests the introduction of techniques that automates the database tuning process. Self- Tuning, or auto-tuning, is a feature that makes systems adaptable in order to keep a good overall performance, reducing as possible the interaction between the administrator and the system. This work proposes an approach for the automatic tuning of DBMSs parameters using an architecture based on software agents. We consider tuning as a global issue, given that changes of a single parameter can be reflected in others. The architecture details, ets implementation and a practical evaluation are also discussed in this dissertation.

La technologie NFC (Near Field Communication) est une nouvelle technique de communication basée sur la technologie RFID (Radio-Fréquence IDentification). La NFC utilise le couplage magnétique entre deux antennes afin de transférer les données et / ou l'énergie entre deux dispositifs électroniques. Elle exploite la fréquence de 13,56 MHz. En raison de la large gamme de dispositifs et d'applications, une définition de la géométrie de l'antenne et de ses paramètres électriques associés est très difficile. En effet, chaque dispositif présente des caractéristiques physiques différentes. En revanche, le circuit intégré (CI) de contrôle NFC est générique et indépendant d'une antenne où d'un dispositif. C'est pourquoi, chaque intégrateur associe le circuit intégré NFC avec une antenne pour chaque dispositif. Or le module de transmission du système NFC nécessite une bonne adaptation de l'antenne à son circuit intégré (IC). Actuellement, cette adaptation est effectuée à la main pour chaque dispositif selon un processus itératif chronophage. En outre, l'adaptation est effectuée une seule fois au moment de la conception du dispositif, quel que soit le mode de communication (lecteur, carte ou peer-to-peer) et à vide c'est-à-dire sans considérer l'influence du dispositif secondaire. Dans ce manuscrit, nous proposons une description détaillée des performances électriques des systèmes NFC. Ensuite un modèle électrique analytique complet et précis de l'antenne NFC est proposé. Enfin, nous développons une nouvelle technique d'adaptation automatique d'impédance afin d'optimiser les performances électriques dans la phase d'émission en termes de transfert d'énergie entre le lecteur et le transpondeur. / Near Field Communication (NFC) is a standardized communication technology derived from Radio Frequency Identification (RFID). NFC uses magnetic induction between two antennas in order to transfer data and/or energy between two electronic devices. NFC operating frequency is 13.56 MHz.Due to the wide range of devices and applications, a predefinition of antenna geometry and corresponding electrical parameters is difficult. In fact, each device shows different antennaphysical characteristics ; On the Other hand, the NFC control integrated circuit (IC) is generic and does not depend on antenna nor a device. Therefore, each integrator associates the NFC IC with a specific antenna for each device. Current NFC transmission modules require the antenna circuitry to be matched with the integrated circuit. Nowadays, the matching is performed manually using a time consuming iterative procedure for each device. Moreover, the matchingcan be done only once at the device design level, regardless of the communication mode (reader, card or peer-to-peer) and regardless of the secondary device influence on the primary antenna characteristics.In this manuscript, we propose a detailed description of the electrical performances of NFC Systems. Then an accurate and complete analytical electrical model of NFC antennas is proposed.Finally, we develop a new technic of automatic adaptation of the matching network in order to optimize the electrical performances in the transmission phase in terms of energy transfer from the reader to the transponder.

With increased and varied performance demands, it is essential that complex multi-standard radio/systems coexist on a same chip. To have cost and performance benefits, these analog/RF systems are implemented in scaled nanometer nodes. At these nodes, the high level of variability in process variations is making the task of manufacturing high fidelity systems a challenge leading to yield and reliability issues. Hence, in the post-manufacturing phase, test and diagnosis steps are critical to identify the cause and effect of the process variations. Further, intelligent post-manufacturing tuning techniques are required to correct the effect of process variations on analog/RF systems. In this work, a die-level concurrent test and diagnosis approach using optimized measurements obtained in high volume manufacturing environment is proposed for analog/RF circuits. Such a simultaneous test and diagnosis methodology enables monitoring parametric process shifts and providing rapid feedback to the fab to minimize or prevent yield loss. In the case of devices that are continuously operating in the field, an efficient on-line diagnosis approach has been developed to perform reliability related prognosis. For advanced RF technologies such as MIMO-OFDM systems, a rapid system-level testing scheme is presented that performs concurrent testing of the multiple RF chains. Depending on the availability of the computational resources and system tuning knobs, different low-cost methodologies for post-manufacture tuning or self-healing of RF SISO/MIMO systems are developed. These include faster digital monitoring and tuning techniques, on-chip tuning techniques using digital logic that enables die-level self-tuning, and DSP-based power conscious iterative techniques for SISO/MIMO RF systems. An adaptive power-performance tuning technique is developed for those devices that have a post-manufacture power consumption value that is more than the acceptable limit. These intelligent post-manufacturing techniques result in reduced manufacturing cost, improved yield, and reliability of analog/RF systems.

Power quality has become one of major concerns in the power industry. It can be described as the reliability of the electric power to maintain continuity operation of end-use equipment. Power quality problems are defined as deviation of voltage or current waveforms from the ideal value. The expansion plan of wind power generation has raised concern regarding how it influences the voltage and current signals. The variability nature of wind energy and the requirements of wind power generation increase the potential problems such as frequency and harmonic distortions. In order to analyze and mitigate problems in wind power generation, it is important to monitor power quality in wind farm. Therefore, the more accurate and reliable parameter estimation methods suitable for wind power generation are needed. Three parameter estimation methods are proposed in this thesis to estimate the unknown parameters, i.e. amplitude and phase angle of fundamental and harmonic components, DC component and system frequency, during the dynamic change in wind farm. In the first method, a self-tuning procedure is introduced to least square method to increase the immunity of the algorithm to noise. In the second method, nonrecursive Newton Type Algorithm is utilised to estimate the unknown parameters by obtaining the left pseudoinverse of Jacobian matrix. In the last technique, unscented transformation is used to replace the linearization procedure to obtain mean and covariance which will be used in Kalman filter method. All of the proposed methods have been tested rigorously using computer simulated data and have shown their capability to track the unknown parameters under extreme distortions. The performances of proposed methods have also been compared using real recorded data from several wind farms in Europe and have demonstrated high correlation. This comparison has verified that UKF requires the shortest processing time and STLS requires the longest.

This article introduces a versatile control board design that can be used in many drying systems using direct heat transfer solutions in combination with static tray distribution based on development of a flexible self-tuning PID controller. The product is applied for a small oven drying solid waste samples or plant materials for further analysis of some parameters. The control board is built based on the Arduino embedded system using a flexible soft PID (Proportional–Integral–Derivative) controller that can automatically change its gains according to the required temperature thresholds to best meet the setpoint of temperatures. The system has a small steady-state error (SSE), fast response to the setpoints and keep stable with temperature deviation when reaching the required threshold around ± 0.5 0C. In addition, the controller board can operate in a variety of modes, including direct temperature operation, pre-set operation, and switching mode. / Bài báo này giới thiệu một thiết kế mạch điều khiển đa năng có thể áp dụng trong nhiều hệ thống sấy sử dụng các giải pháp truyền nhiệt trực tiếp kết hợp phân phối khí kiểu khay tĩnh trên cơ sở phát triển bộ điều khiển PID mềm tự chỉnh linh hoạt. Sản phẩm được ứng dụng cho một mô hình lò nhỏ sấy mẫu chất thải rắn hoặc mẫu thực vật phục vụ các nghiên cứu phân tích thành phần một số chất. Mạch điều khiển được chế tạo trên nền tảng hệ thống nhúng Arduino sử dụng bộ điều khiển PID mềm linh hoạt, có khả năng tự động thay đổi tham số theo ngưỡng nhiệt yêu cầu để đáp ứng nhiệt độ tốt nhất so với ngưỡng nhiệt độ đặt. Hệ thống có độ quá điều chỉnh nhỏ, nhanh đáp ứng tới các ngưỡng đặt và giữ ổn định với sai lệch nhiệt độ khi đạt ngưỡng yêu cầu trong khoảng ±10C. Ngoài ra, bộ điều khiển còn có thể hoạt động theo nhiều chế độ khác nhau, bao gồm hoạt động theo chế độ đặt nhiệt độ trực tiếp, hoạt động theo chu trình đặt trước, và chuyển chế độ hoàn toàn tự động.

The optimal steady-state control, and suboptimal adaptive control, of disturbed single-input-output systems are introduced, and the class of systems considered is defined. It is noted that the stochastic tracking problem divides into a deterministic tracking problem and a stochastic regulator problem; the solutions to these two problems are shown to be independent but formally similar. The continuous regulator problem is approached via both frequency and time domain methods: the former method is extended to cover unstable systems; the latter method is extended to include systems with input delay. The two regulators are shown to be externally equivalent. The frequency domain method is briefly described for discrete systems, and shown to include the minimum variance regulator of Åström and Peterka as a special case. Some systems which allow measurement noise to be treated as a system disturbance for the purposes of optimal controller design are investigated. A novel class of control laws is described in both continuous and discrete time; in the same way as the minimum variance regulator forms the basis of the self-tuning regulator of Åström and Wittenmark, these minimum variance controllers from the basis of a self-tuning controller. These minimum variance controllers have a number of advantages over the minimum-variance regulator, and are open to a number of interpretations including: a model following control law, and an extension of classical control laws to systems with delay. The optimality of this class of control laws is investigated, and analogies drawn with the previously considered k-step-ahead control laws; some examples are given to illustrate the method. An adaptive control law combining the above minimum variance controllers with a linear least-squares algorithm is proposed and shown to be self-tuning. These self-tuning controllers are only slightly more complex than the self-tuning regulator of Åström and Wittenmark, but have a number of advantages. Intuitive justification is given for the conjecture that some methods of Ljung, developed for the analysis of the self-tuning regulator, are applicable to the self-tuning controller. Simulated examples are given which compare and contrast the performance of the self-tuning controller with that of the self-tuning regulator. The first steps towards a quasi-continuous self-tuning controller are outlined.

Made available in DSpace on 2016-12-12T20:27:38Z (GMT). No. of bitstreams: 1 Aldo Zanella Junior.pdf: 3746857 bytes, checksum: 7ff548689a89fd8090402ad4891a23c1 (MD5) Previous issue date: 2015-07-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work introduces the report of performed studies in order to evaluate the applicability of generalized predictive control (GPC) to several plants. The main goal is to analyze the GPC performance in processes with different features, analyzing the influence of its tuning parameters. The study is justified by the fact that GPC presents itself as a generalized solution for several classes of processes, which are becoming increasingly complex and demanding for traditional controllers to handle. For the purpose to prove this proposal of GPC, it was performed several tests with plants of different orders and response characteristics, real and simulated, varying controller tuning parameters and measuring some quality indices. It was evaluated the influence of tuning parameters and it was made a report of conclusions that was reached. Through obtained results, it is shown that GPC satisfies the proposal and presents favorable results. / Esta dissertação traz o relato do estudo realizado a fim de avaliar a aplicabilidade do controlador preditivo generalizado (GPC) em plantas diversas. O objetivo principal é analisar o desempenho do GPC em processos com diferentes características, analisando a influência dos seus parâmetros de sintonia. O estudo se justifica pelo fato de que o GPC apresenta-se como uma solução generalizada para diversos tipos de processos, os quais estão se tornando cada vez mais complexos e com maiores exigências para o controlador. A fim de comprovar essa proposta do GPC, realizou-se inúmeros ensaios com plantas com respostas e ordem diferentes, reais e simuladas, variando-se os parâmetros de sintonia do controlador e medindo-se alguns parâmetros de qualidade. Avaliou-se a influência dos parâmetros de sintonia e fez-se um relato das conclusões a que se chegou. Através dos resultados obtidos, mostra-se que o GPC corresponde ao que se propõe para as plantas testadas e apresenta resultados favoráveis.

[pt] A computação na nuvem vem modificando a maneira pela qual os usuários acessam e usufruem de serviços computacionais. Um sistema gerenciador de banco de dados é um dos principais recursos deste novo ambiente de trabalho. Entretanto, os grandes volumes de dados devem ser adequadamente gerenciados e disponibilizados, de acordo com as oscilações das cargas de trabalho e em função de novos parâmetros existentes. Pelas dimensões do problema neste novo ambiente da nuvem, não há como dispor de um DBA que consiga, manualmente, administrar, manter disponibilidade e desempenho de maneira aceitável. Em particular, há necessidade de sintonia fina (tuning) automática pois o sistema na nuvem deve cumprir requisitos contratuais de operação e, para o usuário, deve-se oferecer recursos como se fossem ilimitados ao mesmo tempo que com excelente desempenho. Nesta dissertação são explicitadas e comparadas as atividades de (auto) sintonia fina em SGBDs que operam em ambientes convencionais e em ambientes de nuvem. Enfatizam-se as diferenças observadas na visão do provedor do serviço de nuvem e dos usuários em um contexto de DBaaS. Nesta pesquisa será proposta uma nova extensão da ontologia de domínio desenvolvida e aprimorada por [Almeida, 2013] e [Oliveira, 2015], a fim de abranger a sintonia fina em banco de dados na nuvem. / [en] Cloud computing is changing the way users access and benefit from computer services. A database manager is one of the main features of this new working environment. However, large volumes of data must be properly managed and made available, according to the fluctuations in workloads and function of new and existing parameters. Because of dimensions problems in this new cloud environment, it is very difficult to have a DBA who can manually manage, maintain availability and performance acceptably. In particular, the necessity of a tuning process automatic in the cloud system to meet contractual operation requirements and the necessity of offering to the user resources as if they were unlimited while with excellent performance. This thesis explains and compares the activities of (self)-tuning database systems operating in conventional and cloud environments, emphasizing the differences observed in the cloud service provider s view and users in a context of DBaaS. In particular, it is proposed to extend of tuning ontology in order to automate actions to tuning the Database as a Service.

Submitted by RAUL KATAYAMA MANSANO null (rkmansano@yahoo.com.br) on 2016-11-04T01:12:57Z No. of bitstreams: 1 Dissertação Raul Katayama Mansano.pdf: 4167710 bytes, checksum: 35cc706c4a721f9334825773f9f2ff77 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-11-10T13:57:40Z (GMT) No. of bitstreams: 1 mansano_rk_me_bauru.pdf: 4167710 bytes, checksum: 35cc706c4a721f9334825773f9f2ff77 (MD5) / Made available in DSpace on 2016-11-10T13:57:40Z (GMT). No. of bitstreams: 1 mansano_rk_me_bauru.pdf: 4167710 bytes, checksum: 35cc706c4a721f9334825773f9f2ff77 (MD5) Previous issue date: 2016-09-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Com os recentes avanços das tecnologias sem fio e a proliferação de sensores sem fio, há um crescente interesse na implementação de Sistemas Controle via Redes Sem Fio (WNCSs), que fornecem vantagens em relação às arquiteturas tradicionais ponto-a-ponto e às arquiteturas de redes cabeadas. Apesar das vantagens, a inserção de redes industriais na malha de controle impõe não-linearidades e restrições que afetam o desempenho e a estabilidade do WNCS. Além disto, uma questão fundamental para aplicações de WNCS é a vida útil da bateria de alimentação dos sensores sem fio, uma vez que é uma fonte limitada de energia. Como a transmissão da informação na rede sem fio requer um alto gasto energético pelo dispositivo, deve-se restringir a quantidade de comunicações para poupar bateria. Esta restrição inviabiliza o uso de sensores sem fio em diversas aplicações de WNCS. Neste contexto, este trabalho apresenta o desenvolvimento de um controlador adaptativo multi-rate para eficiência energética em aplicações industriais de WNCSs, através da diminuição da frequência de transmissão de dados na rede e, portanto, redução do consumo energético dos dispositivos sem fio. Um controlador adaptativo auto-ajustável foi implementado para identificar o modelo do WNCS, simular tal modelo e sintonizar os parâmetros do controlador a cada passo de controle, fornecendo robustez contra distúrbios e não-linearidades inerentes ao WNCS. O diferencial do controlador adaptativo é a incorporação das técnicas de identificação por pacote e de controle multi-rate. A técnica de identificação por pacote consiste em transmitir mensagens com vários dados (não somente o mais atual) coletados durante o período de amostragem do sensor sem fio, melhorando a identificação do modelo do WNCS e, consequentemente, o desempenho do controlador adaptativo. A técnica de controle multi-rate consiste em usar dados virtuais de realimentação, provenientes do modelo simulado do WNCS, para possibilitar uma atuação sobre o processo a uma frequência mais rápida que a amostragem dos sensores sem fio, permitindo a redução das transmissões sem fio do WNCS. Resultados experimentais mostram que o controlador adaptativo multi-rate é robusto e efetivo para aplicações de WNCS, permitindo poupar energia das baterias dos sensores sem fio sem prejudicar significativamente o desempenho de controle do WNCS. As análises do impacto do período de amostragem e do parâmetro Γ do controlador permitiram a obtenção de valores ótimos para a melhoria da eficiência energética do WNCS. / Recent advances in wireless technologies and the proliferation of wireless sensors led to an increasing interest in the implementation of Wireless Networked Control Systems (WNCS), which provide advantages over traditional peer-to-peer and cabled networks architectures. Despite these advantages, inserting a communication network in the control loop impose nonlinearities and constraints which affect stability and performance of the system. Furthermore, a major issue in wireless applications is the lifetime of the sensors batteries, which are a limited source of power. As transmitting data over the network requires high-energy expenditure, it is imperative to reduce the number of communications, in order to save battery. This constraint makes it unfeasible to use wireless sensors in most WNCS applications. In this context, this work aims to develop a multi-rate adaptive controller to enhance energy efficiency in industrial WNCS applications, by reducing frequency of data transmission over the network, thus reducing power expenditure of the wireless devices. A self-tuning adaptive controller is implemented, which can identify the WNCS model, simulate such model and tune the controller parameters at each control step, then providing robustness to disturbance and inherent nonlinearities of the WNCS. The adaptive controller is augmented with a multi-rate control technique and packet-based identification. The packet-based identification consists in transmitting messages with a pack of data (instead of only transmitting the most recent one) sampled during the inter-samples period, thus improving identification of the WNCS model and, consequently, improving control performance. The multi-rate control technique consists in using virtual feedback data, provided by the simulated model of the WNCS, then enabling actuation faster than wireless sampling, allowing the reduction of wireless transmissions in the WNCS. Experimental results show that the implemented multi-rate adaptive controller is robust and effective to WNCS and improve battery lifetime without decreasing control performance of the WNCS significantly. By investigating the impacts of sampling period and of controller parameter Γ determined optimized values to improve energy efficiency of the WNCS.