957 resultados para Programação estocastica


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Given the exponential growth in the spread of the virus world wide web (Internet) and its increasing complexity, it is necessary to adopt more complex systems for the extraction of malware finger-prints (malware fingerprints - malicious software; is the name given to extracting unique information leading to identification of the virus, equivalent to humans, the fingerprint). The architecture and protocol proposed here aim to achieve more efficient fingerprints, using techniques that make a single fingerprint enough to compromise an entire group of viruses. This efficiency is given by the use of a hybrid approach of extracting fingerprints, taking into account the analysis of the code and the behavior of the sample, so called viruses. The main targets of this proposed system are Polymorphics and Metamorphics Malwares, given the difficulty in creating fingerprints that identify an entire family from these viruses. This difficulty is created by the use of techniques that have as their main objective compromise analysis by experts. The parameters chosen for the behavioral analysis are: File System; Records Windows; RAM Dump and API calls. As for the analysis of the code, the objective is to create, in binary virus, divisions in blocks, where it is possible to extract hashes. This technique considers the instruction there and its neighborhood, characterized as being accurate. In short, with this information is intended to predict and draw a profile of action of the virus and then create a fingerprint based on the degree of kinship between them (threshold), whose goal is to increase the ability to detect viruses that do not make part of the same family

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The work consists of analyzing the risk management of investments by applying statistical concepts, economic and mathematical models considering the assets on the market on renowned financial institution. The assessment of these risks becomes increasingly interesting in view of minimizing your losses thus maximizing your chances of gains in both markets boom as extreme uncertainty, even with the sudden changes of scenery. Introducing concepts of investment funds, as well as the classification of the types of funds as funds management and equity, its guidelines, the concept of market investment funds. The types of assets comprising the investment funds, their taxation rules beyond the incidents that market widely used by investors and skilled people, both physical and legal, who keep their resources in this modality. With the historical data collected yields of investment funds of the Bank of Brazil, is an accomplished inflation adjustment and calculated the mean and variance for the verification of the model of Markowitz efficient frontier, a method used as investment analysis. This scan is used Matlab to obtain the set (or border) efficient portfolios. Once verified such data, there will be a critique of the Markowitz model as a quadratic programming and more coherent risk measures currently studied as VaR and CVaR minimizing the expected error, approaching our studies of current research. It is found that such studies have much to be explored, since there are many discussions about how effectively measure risk investments such as its characteristic and behavior, using a time series and volatility

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The following paper means to develop a program to make structural analysis of space trusses. The program to be implemented was based on the concepts of the finite element method and used the programing resources of Visual Basic for Applications (VBA) for the Excel Software®. Being Excel® a software of easy access, low cost, capacity to make matrix calculations and with advanced resources of VBA programing, it is possible to develop an economic solution, efficient and precise for structural analysis of space trusses. Firstly is presented a finite elemento method and the space truss. Then is developed a few important algorithms to be used during the development of the program and also the use of a few resources of VBA. And to validate the quality, efficiency and precision of the results, these are compared with the established commercial software Ansys

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O presente trabalho procura entender como a globalização, através da diversidade cultural, pode interferir na vida profissional das pessoas. Tendo como objeto de estudo as disparidades culturais encontradas na IBM Brasil, o trabalho apresenta conceitos da globalização e indaga suas principais consequências na multinacional em questão. Busca identificar as mudanças necessárias no processo de adequação às diferenças culturais entre países e pessoas, entender como as diferenças interculturais podem afetar a vida dos funcionários e como eles aprenderam a lidar com essas diferenças. De modo geral, procura identificar se a globalização fez com que os profissionais se adequassem às diferenças intercontinentais ou se a própria globalização selecionou os profissionais mais adequados ao mercado global

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In this paper a mathematical model that combines lot-sizing and cutting-stock problems applied to the furniture industry is presented. The model considers the usual decisions of the lot sizing problems, as well as operational decisions related to the cutting machine programming. Two sets of a priori generated cutting patterns are used, industry cutting patterns and a class of n-group cutting patterns. A strategy to improve the utilization of the cutting machine is also tested. An optimization package was used to solve the model and the computational results, using real data from a furniture factory, show that a small subset of n-group cutting patterns provides good results and that the cutting machine utilization can be improved by the proposed strategy.

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Algoritmos para reconhecimento de 3-variedades utilizam-se do conceito de superfície normal, sendo assim, pode-se então tratar problemas de teoria de 3-variedades como sendo de programação linear. Como exemplos tem-se o Algoritmo de reconhecimento da 3-esfera triangulável de Rubinstein-Thompson que é implementado na suíte de software Regina, como a decomposição soma conexa de 3-variedades. A completa classificação de 3-variedades pode ser realizada por meio de algoritmos, possuindo assim relevância para o Programa de Geometrização de Thurston para obtenção de resultados inicialmente utilizando topologia computacional. O objetivo do presente trabalho é discorrer sobre uma aplicação do software Regina. Obteve-se durante a elaboração do presente trabalho, o resultado entre a comparação da 3-esfera homológica de Poincaré com a 3-esfera, parte importante para o entendimento da Conjectura de Poincaré e do Programa de Geometrização.

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Neste trabalho, propomos um modelo integrado de dimensionamento de lotes e programação da produção monomáquina para uma fábrica de refrigerantes de pequeno porte. As decisões de dimensionamento foram baseadas em um modelo encontrado na literatura e as decisões de sequenciamento foram modeladas utilizando restrições do problema do caixeiro viajante assimétrico. Para a validação do modelo proposto foram feitos testes computacionais com exemplares gerados aleatoriamente, e também exemplares baseados em dados reais obtidos da literatura. Os exemplares foram resolvidos pelo método Branch-and-Cut incluído no pacote computacional CPLEX 10.0. Os resultados mostram que o modelo proposto representa o planejamento da produção em fábricas de bebidas monomáquinas e que, em algumas situações, produz resultados melhores que o modelo da literatura.

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This monograph proposes the implementation of a low cost PID controller utilizing a PIC microcontroller, and its application in a positioning system previously controlled by a dedicated integrated circuit for a positioning system. Applying the closed-loop PID control, the system instability was reduced, and its response was smoother, eliminating vibrations and mechanical wear compared to its response with the dedicated integrated circuit, which has a very limited control action. The actuator of the system is a DC motor, whose speed is controlled by the Pulse Width Modulation (PWM) technique, using a Full-Bridge circuit, allowing the shift of direction of rotation. The utilized microcontroller was the PIC16F684, which has an enhanced PWM module, with its analog converters used as reference and position feedback. The positioning sensor is a multiturn potentiometer coupled to the motor axis by gears. The possibility of programming the PID coefficients in the microcontroller, as well as the adjustment of the sampling rate, allows the implemented system achieving high level of versatility

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The present work refers to the design, conception and development of a quadcopter based on PID controllers, a widespread microcontroller on the market was being implemented, the Arduino. Also made use of LabVIEW programming tool from National Instruments company for the quadcopter control and telemetry. For the control, LabVIEW software acquired the joystick commands, making the necessary adjustments to the perfect interpretation by microcontroller on the quadcopter and adjusts the parameters of PID controllers. For telemetry, data relating to quadcopter behavior are received, interpreted and presented in an intuitive user interface. In the first part of this graduate work presents the theoretical background on the subject, with a brief history about the quadcopters, followed by the main projects in the academic and commercial matters. Also are presented the theories of communications used in the design and PID control. Then an overview of the dynamic and mathematical model is demonstrated. Having done this, the physical and computer components required to complete the project are showed and the results are achieved consequently. Finally, a conclusion is made taking into account the results obtained. In this work will be presented the PID control of quadcopter translational movements only to roll and pitch movements

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The search for more reliable security systems and information management of these systems is leading to a growing progress in new technologies investments that allow the implementation of equipment with a high level of reliability, but also have an agile and practical operation. This led people to turn increasingly looking for home automation systems, enterprise and industry for the automation and integration of their systems. The identification by radio frequency is very widespread today for ensuring both agility in handling records data, the reliability of their identification systems, which are increasingly advanced and less susceptible to fraud. Attached to this technology, the use of the database is always very important for the storage of information collected, the area where the MySQL platform is widely used. Using the open source Arduino platform for programming and manipulation of RFID module and LabVIEW software for the union of all these technologies and to develop a user-friendly interface, you can create a highly reliable access control and agility places a high turnover of people. This project aims to prove the advantages of using all these technologies working together, thus improving a flawed system effectively safety, cheaper and quicker

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The friction phenomena is present in mechanical systems with two surfaces that are in contact, which can cause serious damage to structures. Your understanding in many dynamic problems became the target of research due to its nonlinear behavior. It is necessary to know and thoroughly study each existing friction model found in the literature and nonlinear methods to define what will be the most appropriate to the problem in question. One of the most famous friction model is the Coulomb Friction, which is considered in the studied problems in the French research center Laboratoire de Mécanique des Structures et des Systèmes Couplés (LMSSC), where this search began. Regarding the resolution methods, the Harmonic Balance Method is generally used. To expand the knowledge about the friction models and the nonlinear methods, a study was carried out to identify and study potential methodologies that can be applied in the existing research lines in LMSSC and then obtain better final results. The identified friction models are divided into static and dynamic. Static models can be Classical Models, Karnopp Model and Armstrong Model. The dynamic models are Dahl Model, Bliman and Sorine Model and LuGre Model. Concerning about nonlinear methods, we study the Temporal Methods and Approximate Methods. The friction models analyzed with the help of Matlab software are verified from studies in the literature demonstrating the effectiveness of the developed programming

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This work studies the most commonly used methods and make comparisons and discussions of the findings made by each of them and the results provided by them. The objective of this research was to show that the method of characteristics is currently the most efficient method to perform these simulations because of its broad scope low simplifications, requirement allowing to consider every detail of the pipe and fluid. Manual calculations are performed and also a software capable of calculating this phenomenon for various situations, such as water pump, elevated tanks, valves and quick maneuver was developed. The software is based on the method of characteristics that is currently recommended by ABNT. These methods, and the results are obtained numerically and graphically are adopted pipes and amount of downstream conditions and in which will be applied. The conclusions reached showed that the Allievi method is widely used yet because of its efficiency and quick calculation for simple pipes. The method of characteristics, although a lot of work to be calculated due to the calculation is iterative process and requires a program to use it, is the only one that allows the calculation with all amount to the conditions situations and downstream of all the pipe possibilities found

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In industrial plants, there is a department responsible for planning the use of productive resources to find the best possible way to set out plans in strategic, tactical and operational levels. This department is known as PCP or PPCP, which means Planning and Production Control and Planning, Programming and Production Control, respectively. This work presents the use of some of the tools from this department, in particular the Aggregate Production Planning, to propose a new layout of electronic nutrunners for an auto parts industry output line. Through some process indicators analyzes, was identified some productivity losses. The higher loss rate occurred by the electronic nutrunners breaking, and so this work was focused in these devices. Some premises were adopted for the use of electronic nut runners, setting an ideal cycle time for the operation of the production line and making calculations to define the minimum amount of electronic nutrunners to find the production demand without damaging the equipment. With this work we observed that a relevant factor for the constant breaks of electronic nutrunners is because these are working with overload, in other words, the amount of installed equipment is not enough to supply the demand without failures

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Pós-graduação em Engenharia Elétrica - FEIS

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Pós-graduação em Engenharia Elétrica - FEIS