Identificação fuzzy-multimodelos para sistemas não lineares

This paper presents a new multi-model technique of dentification in ANFIS for nonlinear systems. In this technique, the structure used is of the fuzzy Takagi-Sugeno of which the consequences are local linear models that represent the system of different points of operation and the precursors are membership functions whose adjustments are realized by the learning phase of the neuro-fuzzy ANFIS technique. The models that represent the system at different points of the operation can be found with linearization techniques like, for example, the Least Squares method that is robust against sounds and of simple application. The fuzzy system is responsible for informing the proportion of each model that should be utilized, using the membership functions. The membership functions can be adjusted by ANFIS with the use of neural network algorithms, like the back propagation error type, in such a way that the models found for each area are correctly interpolated and define an action of each model for possible entries into the system. In multi-models, the definition of action of models is known as metrics and, since this paper is based on ANFIS, it shall be denominated in ANFIS metrics. This way, ANFIS metrics is utilized to interpolate various models, composing a system to be identified. Differing from the traditional ANFIS, the created technique necessarily represents the system in various well defined regions by unaltered models whose pondered activation as per the membership functions. The selection of regions for the application of the Least Squares method is realized manually from the graphic analysis of the system behavior or from the physical characteristics of the plant. This selection serves as a base to initiate the linear model defining technique and generating the initial configuration of the membership functions. The experiments are conducted in a teaching tank, with multiple sections, designed and created to show the characteristics of the technique. The results from this tank illustrate the performance reached by the technique in task of identifying, utilizing configurations of ANFIS, comparing the developed technique with various models of simple metrics and comparing with the NNARX technique, also adapted to identification

Um ambiente computacional para modelagem simbólica de sistemas físicos lineares

Este trabalho propõe um ambiente computacional aplicado ao ensino de sistemas de controle, denominado de ModSym. O software implementa uma interface gráfica para a modelagem de sistemas físicos lineares e mostra, passo a passo, o processamento necessário à obtenção de modelos matemáticos para esses sistemas. Um sistema físico pode ser representado, no software, de três formas diferentes. O sistema pode ser representado por um diagrama gráfico a partir de elementos dos domínios elétrico, mecânico translacional, mecânico rotacional e hidráulico. Pode também ser representado a partir de grafos de ligação ou de diagramas de fluxo de sinal. Uma vez representado o sistema, o ModSym possibilita o cálculo de funções de transferência do sistema na forma simbólica, utilizando a regra de Mason. O software calcula também funções de transferência na forma numérica e funções de sensibilidade paramétrica. O trabalho propõe ainda um algoritmo para obter o diagrama de fluxo de sinal de um sistema físico baseado no seu grafo de ligação. Este algoritmo e a metodologia de análise de sistemas conhecida por Network Method permitiram a utilização da regra de Mason no cálculo de funções de transferência dos sistemas modelados no software

Análise e síntese de antenas e superfícies seletivas de frequência utilizando computação evolucionária e inteligência de enxames

The frequency selective surfaces, or FSS (Frequency Selective Surfaces), are structures consisting of periodic arrays of conductive elements, called patches, which are usually very thin and they are printed on dielectric layers, or by openings perforated on very thin metallic surfaces, for applications in bands of microwave and millimeter waves. These structures are often used in aircraft, missiles, satellites, radomes, antennae reflector, high gain antennas and microwave ovens, for example. The use of these structures has as main objective filter frequency bands that can be broadcast or rejection, depending on the specificity of the required application. In turn, the modern communication systems such as GSM (Global System for Mobile Communications), RFID (Radio Frequency Identification), Bluetooth, Wi-Fi and WiMAX, whose services are highly demanded by society, have required the development of antennas having, as its main features, and low cost profile, and reduced dimensions and weight. In this context, the microstrip antenna is presented as an excellent choice for communications systems today, because (in addition to meeting the requirements mentioned intrinsically) planar structures are easy to manufacture and integration with other components in microwave circuits. Consequently, the analysis and synthesis of these devices mainly, due to the high possibility of shapes, size and frequency of its elements has been carried out by full-wave models, such as the finite element method, the method of moments and finite difference time domain. However, these methods require an accurate despite great computational effort. In this context, computational intelligence (CI) has been used successfully in the design and optimization of microwave planar structures, as an auxiliary tool and very appropriate, given the complexity of the geometry of the antennas and the FSS considered. The computational intelligence is inspired by natural phenomena such as learning, perception and decision, using techniques such as artificial neural networks, fuzzy logic, fractal geometry and evolutionary computation. This work makes a study of application of computational intelligence using meta-heuristics such as genetic algorithms and swarm intelligence optimization of antennas and frequency selective surfaces. Genetic algorithms are computational search methods based on the theory of natural selection proposed by Darwin and genetics used to solve complex problems, eg, problems where the search space grows with the size of the problem. The particle swarm optimization characteristics including the use of intelligence collectively being applied to optimization problems in many areas of research. The main objective of this work is the use of computational intelligence, the analysis and synthesis of antennas and FSS. We considered the structures of a microstrip planar monopole, ring type, and a cross-dipole FSS. We developed algorithms and optimization results obtained for optimized geometries of antennas and FSS considered. To validate results were designed, constructed and measured several prototypes. The measured results showed excellent agreement with the simulated. Moreover, the results obtained in this study were compared to those simulated using a commercial software has been also observed an excellent agreement. Specifically, the efficiency of techniques used were CI evidenced by simulated and measured, aiming at optimizing the bandwidth of an antenna for wideband operation or UWB (Ultra Wideband), using a genetic algorithm and optimizing the bandwidth, by specifying the length of the air gap between two frequency selective surfaces, using an optimization algorithm particle swarm

Proposta de um sistema de segurança eletrônica predial

This work presents a suggestion of a security system of land automation having as objective main the creation of a system capable from easy method, supervise the installations of a building with the goal to preserver security personal and patrimonial necessities, aim at portability low cost and use easiness. Was designed an alarms central and access controller that has digital and analogical inputs for sensors and outputs for buzzer, telephonic dialing and electronic lock. The system is supervised by software that makes solicitations of information to the alarms central through the one computer's serial port (RS-232). The supervisory software was developed in platform LabVIEW with displays the received data on a graphical interface informing the sensors' current states distributed in the building and system events as alarns occurrences. This system also can be viewed through the Internet for people registered by the land security's system administrator

Síntese de superfícies seletivas de frequência atráves de técnicas de computação natural

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Técnicas de computação natural para segmentação de imagens médicas

Image segmentation is one of the image processing problems that deserves special attention from the scientific community. This work studies unsupervised methods to clustering and pattern recognition applicable to medical image segmentation. Natural Computing based methods have shown very attractive in such tasks and are studied here as a way to verify it's applicability in medical image segmentation. This work treats to implement the following methods: GKA (Genetic K-means Algorithm), GFCMA (Genetic FCM Algorithm), PSOKA (PSO and K-means based Clustering Algorithm) and PSOFCM (PSO and FCM based Clustering Algorithm). Besides, as a way to evaluate the results given by the algorithms, clustering validity indexes are used as quantitative measure. Visual and qualitative evaluations are realized also, mainly using data given by the BrainWeb brain simulator as ground truth

Modelo arquitetural de comunicação para monitoramento de pacientes baseado em middleware, computação móvel e ubíqua

Hospital Automation is an area that is constantly growing. The emergency of new technologies and hardware is transforming the processes more efficient. Nevertheless, some of the hospital processes are still being performed manually, such as monitoring of patients that is considered critical because it involves human lives. One of the factors that should be taken into account during a monitoring is the agility to detect any abnormality in vital signs of patients, as well as warning of this anomaly to the medical team involved. So, this master's thesis aims to develop an architecture to automate this process of monitoring and reporting of possible alert to a professional, so that emergency care can be done effectively. The computing mobile was used to improve the communication by distributing messages between a central located into the hospital and the mobile carried by the duty

Desenvolvimento de um simulador de bombeio por cavidades progressivas

The method of artificial lift of progressing cavity pump is very efficient in the production of oils with high viscosity and oils that carry a great amount of sand. This characteristic converted this lift method into the second most useful one in oil fields production. As it grows the number of its applications it also increases the necessity to dominate its work in a way to define it the best operational set point. To contribute to the knowledge of the operational method of artificial lift of progressing cavity pump, this work intends to develop a computational simulator for oil wells equipped with an artificial lift system. The computational simulator of the system will be able to represent its dynamic behavior when submitted to the various operational conditions. The system was divided into five subsystems: induction motor, multiphase flows into production tubing, rod string, progressing cavity pump and annular tubing-casing. The modeling and simulation of each subsystem permitted to evaluate the dynamic characteristics that defined the criteria connections. With the connections of the subsystems it was possible to obtain the dynamic characteristics of the most important arrays belonging to the system, such as: pressure discharge, pressure intake, pumping rate, rod string rotation and torque applied to polish string. The shown results added to a friendly graphical interface converted the PCP simulator in a great potential tool with a didactic characteristic in serving the technical capability for the system operators and also permitting the production engineering to achieve a more detail analysis of the dynamic operational oil wells equipped with the progressing cavity pump

Desenvolvimento e testes de software de um receptor de GPS para uso espacial

Spacecraft move with high speeds and suffer abrupt changes in acceleration. So, an onboard GPS receiver could calculate navigation solutions if the Doppler effect is taken into consideration during the satellite signals acquisition and tracking. Thus, for the receiver subject to such dynamic cope these shifts in the frequency signal, resulting from this effect, it is imperative to adjust its acquisition bandwidth and increase its tracking loop to a higher order. This paper presents the changes in the GPS Orion s software, an open architecture receiver produced by GEC Plessey Semiconductors, nowadays Zarlink, in order to make it able to generate navigation fix for vehicle under high dynamics, especially Low Earth Orbit satellites. GPS Architect development system, sold by the same company, supported the modifications. Furthermore, it presents GPS Monitor Aerospace s characteristics, a computational tool developed for monitoring navigation fix calculated by the GPS receiver, through graphics. Although it was not possible to simulate the software modifications implemented in the receiver in high dynamics, it was observed that the receiver worked in stationary tests, verified also in the new interface. This work also presents the results of GPS Receiver for Aerospace Applications experiment, achieved with the receiver s participation in a suborbital mission, Operation Maracati 2, in December 2010, using a digital second order carrier tracking loop. Despite an incident moments before the launch have hindered the effective navigation of the receiver, it was observed that the experiment worked properly, acquiring new satellites and tracking them during the VSB-30 rocket flight.

Arquitetura de Software para Barcos Robóticos

We propose in this work a software architecture for robotic boats intended to act in diverse aquatic environments, fully autonomously, performing telemetry to a base station and getting this mission to be accomplished. This proposal aims to apply within the project N-Boat Lab NatalNet DCA, which aims to empower a sailboat navigating autonomously. The constituent components of this architecture are the memory modules, strategy, communication, sensing, actuation, energy, security and surveillance, making these systems the boat and base station. To validate the simulator was developed in C language and implemented using the graphics API OpenGL resources, whose main results were obtained in the implementation of memory, performance and strategy modules, more specifically data sharing, control of sails and rudder and planning short routes based on an algorithm for navigation, respectively. The experimental results, shown in this study indicate the feasibility of the actual use of the software architecture developed and their application in the area of autonomous mobile robotics

Comunicação gráfica em interfaces de hipermídia de educação a distância via web

This study aims to analyze the communication graphics of layouts of hypermedia interfaces oriented to Distance Education via the Internet. This proposal is justified by widening the offer of courses that modality and the consequent application of items of hypermedia for teaching-learning. The method of analysis involved the search nethnographic, addressed to the cycle student intermediary of the Training Program Continuing Medias in Education, and the evaluation heuristic of the interfaces of Virtual Learning Environment "E-Proinfo" and of the modules of the Cycle. This evaluation we observed the implementation of the attributes of usability and the degree of interactivity of each interface. The results revealed an inefficient implementation of the attributes of usability, which meant a consequent reduction of the levels of interactivity. As proposing the present Design Virtual Learning, a model of hypermedia layout, designed to generate usability for Virtual learning environments and extend the acquisition of literancy for students and tutors. This proposal design not hypermedia aims the demarcation of models pre-conceived, but the proposal of layout in which each element of hypermedia is applied with a view to generate a seaworthiness intuitive, more agile and efficient, in these ambients

Uma plataforma de integração de middleware para computação ubíqua

One of the current challenges of Ubiquitous Computing is the development of complex applications, those are more than simple alarms triggered by sensors or simple systems to configure the environment according to user preferences. Those applications are hard to develop since they are composed by services provided by different middleware and it is needed to know the peculiarities of each of them, mainly the communication and context models. This thesis presents OpenCOPI, a platform which integrates various services providers, including context provision middleware. It provides an unified ontology-based context model, as well as an environment that enable easy development of ubiquitous applications via the definition of semantic workflows that contains the abstract description of the application. Those semantic workflows are converted into concrete workflows, called execution plans. An execution plan consists of a workflow instance containing activities that are automated by a set of Web services. OpenCOPI supports the automatic Web service selection and composition, enabling the use of services provided by distinct middleware in an independent and transparent way. Moreover, this platform also supports execution adaptation in case of service failures, user mobility and degradation of services quality. The validation of OpenCOPI is performed through the development of case studies, specifically applications of the oil industry. In addition, this work evaluates the overhead introduced by OpenCOPI and compares it with the provided benefits, and the efficiency of OpenCOPI s selection and adaptation mechanism

Uma estratégia dirigida a modelos e baseada em linguagem de descrição arquitetural para linhas de produtos de software

Model-oriented strategies have been used to facilitate products customization in the software products lines (SPL) context and to generate the source code of these derived products through variability management. Most of these strategies use an UML (Unified Modeling Language)-based model specification. Despite its wide application, the UML-based model specification has some limitations such as the fact that it is essentially graphic, presents deficiencies regarding the precise description of the system architecture semantic representation, and generates a large model, thus hampering the visualization and comprehension of the system elements. In contrast, architecture description languages (ADLs) provide graphic and textual support for the structural representation of architectural elements, their constraints and interactions. This thesis introduces ArchSPL-MDD, a model-driven strategy in which models are specified and configured by using the LightPL-ACME ADL. Such strategy is associated to a generic process with systematic activities that enable to automatically generate customized source code from the product model. ArchSPLMDD strategy integrates aspect-oriented software development (AOSD), modeldriven development (MDD) and SPL, thus enabling the explicit modeling as well as the modularization of variabilities and crosscutting concerns. The process is instantiated by the ArchSPL-MDD tool, which supports the specification of domain models (the focus of the development) in LightPL-ACME. The ArchSPL-MDD uses the Ginga Digital TV middleware as case study. In order to evaluate the efficiency, applicability, expressiveness, and complexity of the ArchSPL-MDD strategy, a controlled experiment was carried out in order to evaluate and compare the ArchSPL-MDD tool with the GingaForAll tool, which instantiates the process that is part of the GingaForAll UML-based strategy. Both tools were used for configuring the products of Ginga SPL and generating the product source code

Mestre em Sistemas e Computação

In this work will applied the technique of Differential Cryptanalysis, introduced in 1990 by Biham and Shamir, on Papílio s cryptosystem, developed by Karla Ramos, to test and most importantly, to prove its relevance to other block ciphers such as DES, Blowfish and FEAL-N (X). This technique is based on the analysis of differences between plaintext and theirs respective ciphertext, in search of patterns that will assist in the discovery of the subkeys and consequently in the discovery of master key. These differences are obtained by XOR operations. Through this analysis, in addition to obtaining patterns of Pap´ılio, it search to obtain also the main characteristics and behavior of Papilio throughout theirs 16 rounds, identifying and replacing when necessary factors that can be improved in accordance with pre-established definitions of the same, thus providing greater security in the use of his algoritm

Joker: um realizador de desenhos animados para linguagens formais

Using formal methods, the developer can increase software s trustiness and correctness. Furthermore, the developer can concentrate in the functional requirements of the software. However, there are many resistance in adopting this software development approach. The main reason is the scarcity of adequate, easy to use, and useful tools. Developers typically write code and test it. These tests usually consist of executing the program and checking its output against its requirements. This, however, is not always an exhaustive discipline. On the other side, using formal methods one might be able to investigate the system s properties further. Unfortunately, specification languages do not always have tools like animators or simulators, and sometimes there are no friendly Graphical User Interfaces. On the other hand, specification languages usually have a compiler which normally generates a Labeled Transition System (LTS). This work proposes an application that provides graphical animation for formal specifications using the LTS as input. The application initially supports the languages B, CSP, and Z. However, using a LTS in a specified XML format, it is possible to animate further languages. Additionally, the tool provides traces visualization, the choices the user did, in a graphical tree. The intention is to improve the comprehension of a specification by providing information about errors and animating it, as the developers do for programming languages, such as Java and C++.