<p>Revenue maximization for network operators is considered as a criterion for resource allocation in wireless cellular networks. A business model encompassing service level agreements between network operators and service providers is presented. Admission control, through price model aware admission policing and service level control, is critical for the provisioning of useful services over a general purpose wireless network. A technical solution consisting of a fast resource scheduler taking into account service requirements and wireless channel properties, a service level controller that provides the scheduler with a reasonable load, and an admission policy to uphold the service level agreements and maximize revenue, is presented.</p><p>Two different types of service level controllers are presented and implemented. One is based on a scalar PID controller, that adjusts the admitted data rates for all active clients. The other one is obtained with linear programming methods, that optimally assign data rates to clients, given their channel qualities and price models.</p><p>Two new scheduling criteria, and algorithms based on them, are presented and evaluated in a simulated wireless environment. One is based on a quadratic criterion, and is implemented through approximative algorithms, encompassing a search based algorithm and two different linearizations of the criterion. The second one is based on statistical measures of the service rates and channel states, and is implemented as an approximation of the joint probability of achieving the delay limits while utilizing the available resources efficiently.</p><p>Two scheduling algorithms, one based on each criterion, are tested in combination with each of the service level controllers, and evaluated in terms of throughput, delay, and computational complexity, using a target test system. Results show that both schedulers can, when feasible, meet explicit throughput and delay requirements, while at the same time allowing the service level controller to maximize revenue by allocating the surplus resources to less demanding services.</p>

Revenue maximization for network operators is considered as a criterion for resource allocation in wireless cellular networks. A business model encompassing service level agreements between network operators and service providers is presented. Admission control, through price model aware admission policing and service level control, is critical for the provisioning of useful services over a general purpose wireless network. A technical solution consisting of a fast resource scheduler taking into account service requirements and wireless channel properties, a service level controller that provides the scheduler with a reasonable load, and an admission policy to uphold the service level agreements and maximize revenue, is presented. Two different types of service level controllers are presented and implemented. One is based on a scalar PID controller, that adjusts the admitted data rates for all active clients. The other one is obtained with linear programming methods, that optimally assign data rates to clients, given their channel qualities and price models. Two new scheduling criteria, and algorithms based on them, are presented and evaluated in a simulated wireless environment. One is based on a quadratic criterion, and is implemented through approximative algorithms, encompassing a search based algorithm and two different linearizations of the criterion. The second one is based on statistical measures of the service rates and channel states, and is implemented as an approximation of the joint probability of achieving the delay limits while utilizing the available resources efficiently. Two scheduling algorithms, one based on each criterion, are tested in combination with each of the service level controllers, and evaluated in terms of throughput, delay, and computational complexity, using a target test system. Results show that both schedulers can, when feasible, meet explicit throughput and delay requirements, while at the same time allowing the service level controller to maximize revenue by allocating the surplus resources to less demanding services.

The behaviour of a large nuclear reactor can be described with sufficient accuracy using a nodal model, like the spatial model of a 540 MWe large Pressurized Heavy Water Reactor (PHWR). This model divides the reactor into divisions or nodes to create a spatial model in order to control the xenon induced oscillations that occur in PHWRs. However, being such a large scale system, a 72nd-order model, it makes controller design challenging. Therefore, a reduced order model is much more manageable. A convenient method of model reduction while maintaining the important dynamics characteristics of the process can be done by decoupling. Also, due to the nature of the system, decentralized controllers could serve as a better option because it allows each controller to be localized. This way, any control input to a zone only affects the desired zone and the zones most coupled with, thus not causing a respective change in neutron flux in the other zones. In this thesis, three decentralized controllers were designed using the spatial model of a 540 MWe large PHWR. A decoupling algorithm was designed to divide the system into three partitions containing 20, 27, and 25 states each. Reduced order sub-systems were thus created to produce optimal decentralized controllers. An optimal centralized controller was created to compare both approaches. The decentralized versus centralized controllers’ system responses were analyzed after a reactivity disturbance. A fail-safe study was done to highlight one of the advantages of decentralized controllers. / UOIT

Made available in DSpace on 2014-12-17T14:55:51Z (GMT). No. of bitstreams: 1 MarcioEUA_DISSERT.pdf: 7811126 bytes, checksum: a8663444eeaf1a908fcd7146c171a40a (MD5) Previous issue date: 2011-09-02 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Fuzzy intelligent systems are present in a variety of equipment ranging from household appliances to Fuzzy intelligent systems are present in a variety of equipment ranging from household appliances to small devices such as digital cameras and cell phones being used primarily for dealing with the uncertainties in the modeling of real systems. However, commercial implementations of Fuzzy systems are not general purpose and do not have portability to different hardware platforms. Thinking about these issues this work presents the implementation of an open source development environment that consists of a desktop system capable of generate Graphically a general purpose Fuzzy controller and export these parameters for an embedded system with a Fuzzy controller written in Java Platform Micro Edition To (J2ME), whose modular design makes it portable to any mobile device that supports J2ME. Thus, the proposed development platform is capable of generating all the parameters of a Fuzzy controller and export it in XML file, and the code responsible for the control logic that is embedded in the mobile device is able to read this file and start the controller. All the parameters of a Fuzzy controller are configurable using the desktop system, since the membership functions and rule base, even the universe of discourse of the linguistic terms of output variables. This system generates Fuzzy controllers for the interpolation model of Takagi-Sugeno. As the validation process and testing of the proposed solution the Fuzzy controller was embedded on the mobile device Sun SPOT ? and used to control a plant-level Quanser?, and to compare the Fuzzy controller generated by the system with other types of controllers was implemented and embedded in sun spot a PID controller to control the same level plant of Quanser? / Sistemas inteligentes Fuzzy est?o presentes nos mais variados equipamentos, desde eletrodom?sticos e m?quinas industriais at? dispositivos de pequeno porte, como m?quinas digitais e aparelhos celulares, sendo utilizados principalmente por lidar com as incertezas inerentes a modelagem dos sistemas reais. No entanto, as implementa??es comerciais de sistemas Fuzzy n?o s?o de prop?sito geral e n?o apresentam portabilidade para diferentes plataformas de hardware. Sobre essas quest?es, este trabalho apresenta a implementa??o de um ambiente de desenvolvimento open source composto de um sistema desktop capaz de gerar graficamente um controlador Fuzzy de prop?sito geral e exportar estes par?metros para um sistema embarcado com um controlador Fuzzy escrito em Java To Plataform Micro Edition (J2ME), cuja concep??o modular o torna port?vel para qualquer dispositivo m?vel que suporte J2ME. Desta forma, a plataforma de desenvolvimento proposta ? capaz de gerar todos os par?metros de um controlador Fuzzy e export?-lo em arquivo XML. O c?digo respons?vel pela l?gica de controle que se encontra embarcado no dispositivo m?vel ? capaz de ler o arquivo e iniciar o controlador. Todos os par?metros de um controlador Fuzzy s?o configur?veis atrav?s do sistema desktop, desde as fun??es de pertin?ncia e base de regras at? o universo de discurso dos termos lingu?sticos das vari?veis de sa?da. O sistema proposto gera controladores Fuzzy para o modelo de interpola??o do tipo Takagi-Sugeno. Como processo de valida??o e testes da solu??o proposta, o controlador Fuzzy foi embarcado no dispositivo m?vel Sun SPOT? e usado para controle de uma planta de n?vel da Quanser?, e para compara??o do controlador Fuzzy gerado pelo sistema com outros tipos de controladores foi implementado e embarcado no Sun SPOT um controlador PID para a mesma planta de n?vel.

Buffer tanks are widely used within the process industry to prevent flow variations from being directly propagated throughout a plant. The capacity of the tank is used to smoothly transfer inlet flow upsets to the outlet. Ideally, the tank thus works as a low pass filter where the available tank capacity limits the achievable flow smoothing. For infrequently occurring upsets, where the system has time to reach steady state between flow changes, the averaging level control problem has been extensively studied. After an inlet flow change, flow filtering has traditionally been obtained by letting the tank level deviate from its nominal value while slowly adapting the outlet to cancel out the flow imbalance and eventually bringing back the level to its set-point. The system is then again in steady state and ready to surge the next upset. By ensuring that the single largest upset can be handled without violating the level constraints, satisfactory flow smoothing is obtained. In this thesis, the smoothing of frequently changing inlet flows is addressed. In this case, standard level controllers struggle to obtain acceptable flow smoothing since the system rarely is in steady state and flow upsets can thus not be treated as separate events. To obtain a control law that achieves optimal filtering while directly accounting for future upsets, the averaging level control problem was approached using robust model predictive control (MPC). The robust MPC differs in the way it obtains flow smoothing by not returning the tank level to a fixed set-point. Instead, it lets the steady state tank level depend on the current value of the inlet flow. This insight was then used to propose a linear control structure, designed to filter frequent upsets optimally. Analyses and simulation results indicate that the proposed linear and robust MPC controller obtain flow smoothing comparable to the standard optimal averaging level controllers for infrequent upsets while handling frequent upsets considerably better.

The aim of this work is design, realization, and measurement of wideband microwave generator, which is based on the ADF4350 frequency synthesizers. The generator uses the principle of mixing, for frequencies up to 2.2GHz. Higher frequencies are obtained through direct channels. The first part describes the theory of phase locked loop . The following section describes the parameters of the ADF4350 and their management. A PCB was also designed to control the generator with Atmel s AVR AT-mega32. The Generator software is written in AVR Studio in C programming language. The realized generator is housed in a stainless steel box and can be controlled using the keyboard and PC.

Šio darbo tikslas – suprojektuoti ir išanalizuoti skysčio lygio valdymo sistemas su PI reguliatoriumi bei neraiškiosios logikos reguliatoriumi, atlikti imitacijas ir palyginti gautus rezultatus. Teorinėje dalyje apžvelgiamos skysčio lygio valdymo sistemos, jų pagrindiniai elementai. Taip pat išnagrinėjami sistemų valdymo ypatumai, naudojant neraiškiosios logikos ir PI reguliatorius. Tiriamojoje dalyje sudaryta: sistemos funkcinė schema, sistemos matematinis ir kompiuterinis modeliai. Atlikus procesų imitaciją nustatyta, kad sistemoje su PI reguliatoriumi pakeitus nuostatą dėl perreguliavimo gaunamos nepageidaujamos slėgio aukščio ir debito vertės. To išvengiama, naudojant neraiškiosios logikos reguliatorių. Darbo pabaigoje pateikiamos išvados. Darbą sudaro 7 dalys: įvadas, literatūros apie skysčio lygio valdymo sistemas analizė, tyrimo tikslas ir uždaviniai, teorinė dalis, tiriamoji dalis, išvados, literatūra. Darbo apimtis - 71 puslapiai be grafinės dalies, 53 iliustracijos, 6 lentelės, 40 bibliografinių šaltinių ir 4 internetinės prieigos. / The main goal of the thesis is to design and analyze liquid level control systems with a PI controller and a fuzzy logic controller, perform simulations and to compare the results. In the analytical part, liquid level control systems and main elements of liquid level control systems are overviewed. Also system control using PI and Fuzzy logic regulators is overviewed. In research part liquid level control system is projected practically. The research chapter consists of a functional scheme, mathematical and computer models design. The simulation of the system shows that changing the step size in the system with a PI controller results in unwanted total head and flow rate values because of an overshoot. This is avoided in the system with a fuzzy controller. At the end of the thesis there is a conclusions part. The work consists of seven parts: introduction, analysis of liquid level control system literature, main goal of the research, theory part, design part, conclusions, references. Work volume – 71 pages of text without appendixes, 53 illustrations, 6 tables, 40 bibliographical and 4 internet entries.

Uma das técnicas de controle avançado que vem ganhando destaque no cenário econômico e ecológico, focando maior sustentabilidade e a otimização dos processos, é o controle preditivo, o qual já vem sendo aplicado em indústrias químicas e petroquímicas. Esta dissertação trata do desenvolvimento de um controle preditivo aplicado a uma planta piloto de neutralização de pH, presente no Laboratório de Controle de Processos Industriais da Escola Politécnica da Universidade de São Paulo. O desenvolvimento do projeto pode ser dividido em quatro etapas: implementação das malhas de controle regulatório, identificação dos sistemas, construção do controlador preditivo, aplicações e análises experimentais. Na primeira etapa foi necessário estudar o sistema em questão e implementar algumas malhas internas usando controladores PID. Na segunda etapa foi realizada a identificação do modelo da planta, ressaltando que pontos de operação e ajuste de parâmetros internos são determinantes para a modelagem. Já na terceira etapa desenvolveu-se um controlador preditivo, através de softwares auxiliares como o MATLAB e o IIT 800xA da ABB, que foram utilizados para o desenvolvimento e implementação do algoritmo de controle. Por fim, na última etapa, foi feita a análise e comparação dos resultados, quando se submete à planta a um controlador PID, quando aplicado um controlador preditivo em cascata com controladores PID e quando se utiliza apenas o controlador preditivo com ação direta nos atuadores. / The predictive control is an advanced control technique which has gained evidence in the economic and ecological context because the search for sustainability and process optimization. This control has already been applied by the chemical and petrochemical industries. The purpose of this project is to develop a predictive controller which will be applied in a pH neutralization plant located in the Industrial Processes Control Laboratory at Polytechnic School of the University of São Paulo. The development of this project can be divided into four stages: implementation of regulatory control loops, identification of the system, construction of the predictive controller, applications and experimental analysis. The first step is necessary in order to study the plant and to implement some internal loops using PID controllers. In the second step, the identification process of the plant model will be done. It is important to note that operating points and internal parameter settings are very important for modeling. In the third stage, using the model obtained from the identification process, a predictive controller is built from auxiliary software such as MATLAB and IIT 800xA (by ABB), which will be used for the development and implementation of the control algorithm. Finally, the last step consists in collecting and analyzing the results of the pH neutralization plant. At this stage the responses of each controller will be compared: PID controller, MPC controller in cascade mode with PID and MPC controller acting directly on actuators.

Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2017-08-23T12:28:02Z No. of bitstreams: 1 André Augusto Andreis_.pdf: 7251218 bytes, checksum: 7b71c418da3bd1942b6b1bf3e213a439 (MD5) / Made available in DSpace on 2017-08-23T12:28:02Z (GMT). No. of bitstreams: 1 André Augusto Andreis_.pdf: 7251218 bytes, checksum: 7b71c418da3bd1942b6b1bf3e213a439 (MD5) Previous issue date: 2017-06-22 / Nenhuma / Os processos industriais são de natureza dinâmica, variando continuamente no tempo devido a perturbações externas ou por alterações no processo e, portanto, a necessidade de controle automático das variáveis é uma realidade, principalmente devido ao aumento da complexidade dos sistemas instalados nas últimas décadas. Mediante a importância dos controladores, esta pesquisa traz o estudo de técnicas para avaliação do desempenho e sintonia de controladores de nível, bem como orienta quanto à escolha de índices a serem utilizados para a avaliação do desempenho de controladores de nível, segundo o objetivo de controle, apresentando a magnitude do erro obtido quando utilizado um índice de avaliação de desempenho inadequado. Aborda-se sistemas de controle de nível que têm como objetivo manter o nível na referência de forma precisa ou minimizar a variância da vazão de saída. Apresenta-se uma proposta de metodologia para a avaliação do desempenho e para a sintonia de controladores de nível através da modelagem do processo e da resolução de um problema de otimização. A metodologia proposta é aplicada a um processo de nível autorregulatório. Explora-se a eficácia dos índices de avaliação de desempenho para controladores de nível, considerando diferentes tipos de perturbação na vazão de entrada. Comparam-se técnicas tradicionais e técnicas que utilizam otimização para a sintonia de controladores, sendo que as técnicas de otimização apresentam resultados melhores que as técnicas tradicionais. Apresenta-se o impacto de incertezas no modelo utilizado para obter os parâmetros do controlador através de técnicas de otimização no qual, dependendo do objetivo de controle e do tipo de perturbação de entrada, ocorrem discrepâncias a serem consideradas em relação a necessidade de ressintonia do controlador. Analisa-se as consequências do uso de índices de avaliação de desempenho inadequados. Por meio dos resultados obtidos verificou-se que para determinar o índice adequado para a avaliação do desempenho de controladores de nível deve-se identificar o objetivo de controle de forma correta, o que nem sempre ocorre, pois em geral, sistemas de suporte à decisão disponibilizam índices de avaliação de desempenho que consideram a variável de processo, mas algumas malhas de controle podem considerar a variável manipulada. / Industrial processes are of a dynamic nature, varying continuously in time due to external disturbances or changes in the process and, therefore, the need for automatic control of variables is a reality, mainly due to the complexity increase of the systems installed in last decades. Due to the importance of controllers, this research brings the study of techniques for performance assessment and tuning of level controllers, as well as guides the choice of indexes to be used for the performance assessment of level controllers, according to the control objective, presenting the magnitude of the error obtained when used an inadequate performance assessment index. It addresses level control systems that aim to maintain the level in the reference accurately or minimize the outlet flow variance. It is presented a proposal of methodology for performance assessment and tuning of level controllers through process modeling and solving an optimization problem. The proposed methodology is applied to a self-regulatory process. The effectiveness of the performance assessment index for level controllers is explored, considering different types of perturbation in the inlet flow. Traditional techniques and optimization techniques for controller tuning are compared, being that optimization techniques present better results than traditional techniques. It is presented the uncertainties impact in the model used to obtain the controller parameters through optimization techniques in which, depending on the control objective and the type of input disturbance, there are discrepancies to be considered in relation to the need for controller retuning. The consequences of using inadequate performance assessment index are analyzed. Through the obtained results it was verified that to determine the adequate index for the performance assessment level controllers one must identify correctly the control objective, which does not always occur, since the systems of support to the decision in general provide performance assessment indexes that consider the process variable, but some control meshes may consider the manipulated variable.

This master thesis deals with the virtual gate position and liquid level control system. The main characteristics of automatic control systems, fuzzy logic systems, their properties and formation principles are reviewed. Conventional and advanced control methods are presented pointing out their benefits, drawbacks and problems to be solved. Physical modelling and simulation issues are also discussed. Physical, mathematical, simulation and animation models of the system are produced. Position and level controllers are designed. The simulation of gate position and liquid level control processes is performed. The simulation model is built up using MATLAB Simulink and Fuzzy Logic Toolbox. The simulation results prove that the proportional controller fits very well for controlling gate position. However, the results of liquid level control “upwards” using PI controller are only satisfactory. Unsatisfactory results are obtained using the same controller for liquid level control “downwards”. Substantially better results are achieved using fuzzy logic controller. The models produced can be useful for further investigations and learning purposes.