Estudo da viabilidade do desenvolvimento de sistemas integrados baseados em redes em chip sem processadores: sistema IPNoSys

The increase of capacity to integrate transistors permitted to develop completed systems, with several components, in single chip, they are called SoC (System-on-Chip). However, the interconnection subsystem cans influence the scalability of SoCs, like buses, or can be an ad hoc solution, like bus hierarchy. Thus, the ideal interconnection subsystem to SoCs is the Network-on-Chip (NoC). The NoCs permit to use simultaneous point-to-point channels between components and they can be reused in other projects. However, the NoCs can raise the complexity of project, the area in chip and the dissipated power. Thus, it is necessary or to modify the way how to use them or to change the development paradigm. Thus, a system based on NoC is proposed, where the applications are described through packages and performed in each router between source and destination, without traditional processors. To perform applications, independent of number of instructions and of the NoC dimensions, it was developed the spiral complement algorithm, which finds other destination until all instructions has been performed. Therefore, the objective is to study the viability of development that system, denominated IPNoSys system. In this study, it was developed a tool in SystemC, using accurate cycle, to simulate the system that performs applications, which was implemented in a package description language, also developed to this study. Through the simulation tool, several result were obtained that could be used to evaluate the system performance. The methodology used to describe the application corresponds to transform the high level application in data-flow graph that become one or more packages. This methodology was used in three applications: a counter, DCT-2D and float add. The counter was used to evaluate a deadlock solution and to perform parallel application. The DCT was used to compare to STORM platform. Finally, the float add aimed to evaluate the efficiency of the software routine to perform a unimplemented hardware instruction. The results from simulation confirm the viability of development of IPNoSys system. They showed that is possible to perform application described in packages, sequentially or parallelly, without interruptions caused by deadlock, and also showed that the execution time of IPNoSys is more efficient than the STORM platform

Regulador eletromagnético de frequência aplicado no controle de velocidade de geradores eólicos

The constant necessity for new sources of renewable energy is increasingly promoting the increase of investments in this area. Among other sources, the wind power has been becoming prominent. It is important to promote the search for the improvement of the technologies involved in the topologies of the wind turbines, seeking for alternatives which enhance the gotten performance, despite the irregularity of the wind speed. This study presents a new system for speed control, in this case applied to the wind turbines - the Electromagnetic Frequency Regulator (EFR). One of the most used devices in some topologies is the mechanical gearboxes which, along with a short service life, often represent sources of noise and defects. The EFR does not need these transmission boxes, representing a technological advancement, using for that an adapted induction machine, in which the stator becomes mobile, supportive to the axis of the turbine. In the topology used in this study, the EFR also allows us to leave out the usage of the eletronic converters to establish the coupling between the generator and the electrical grid. It also the reason why it provides the possibility of obtaining the generation in alternating current, with constant voltage and frequency, where there is no electrical grid. Responsable for the mechanical speed control of the generator, the EFR can be useful in other transmission systems in which the mechanical speed control output is the objective. In addition, the EFR operates through the combination of two inputs, a mechanical and other electrical. It multiplies the possibilities of application because it is able to synergistic coupling between different arrays of energy, and, for such reasons, it enables the various sources of energy involved to be uncoupled from the network, being the synchronous generator responsible for the system connection with the electrical grid, simplifying the control strategies on the power injected in it. Experimental and simulation results are presented through this study, about a wind turbine, validating the proposal related to the efficience in the speed control of the system for different wind conditions.

A methodology for building energy modelling and calibration in warm climates

PEDRINI, Aldomar; WESTPHAL, F. S.; LAMBERT, R.. A methodology for building energy modelling and calibration in warm climates. Building And Environment, Australia, n. 37, p.903-912, 2002. Disponível em: user=687335&_pii=S0360132302000513&_origin=search&_coverDate=09%2F30%2F2002&_sk=999629991&view=c&wchp=dGLzVtb-zSkzV&md5=f6342003b53dd1448e30308d082ba957&ie=/sdarticle.pdf>. Acesso em: 04 out. 2010.

Utilização de um aplicativo de simulação computacional na avaliação de desempenho térmico de protótipo de habitação de interesse social (his)

This Masters Degree dissertation seeks to make a comparative study of internal air temperature data, simulated through the thermal computer application DesignBuilder 1.2, and data registered in loco through HOBO® Temp Data Logger, in a Social Housing Prototype (HIS), located at the Central Campus of the Federal University of Rio Grande do Norte UFRN. The prototype was designed and built seeking strategies of thermal comfort recommended for the local climate where the study was carried out, and built with panels of cellular concrete by Construtora DoisA, a collaborator of research project REPESC Rede de Pesquisa em Eficiência Energética de Sistemas Construtivos (Research Network on Energy Efficiency of Construction Systems), an integral part of Habitare program. The methodology employed carefully examined the problem, reviewed the bibliography, analyzing the major aspects related to computer simulations for thermal performance of buildings, such as climate characterization of the region under study and users thermal comfort demands. The DesignBuilder 1.2 computer application was used as a simulation tool, and theoretical alterations were carried out in the prototype, then they were compared with the parameters of thermal comfort adopted, based on the area s current technical literature. Analyses of the comparative studies were performed through graphical outputs for a better understanding of air temperature amplitudes and thermal comfort conditions. The data used for the characterization of external air temperature were obtained from the Test Reference Year (TRY), defined for the study area (Natal-RN). Thus the author also performed comparative studies for TRY data registered in the years 2006, 2007 and 2008, at weather station Davis Precision Station, located at the Instituto Nacional de Pesquisas Espaciais INPE-CRN (National Institute of Space Research), in a neighboring area of UFRN s Central Campus. The conclusions observed from the comparative studies performed among computer simulations, and the local records obtained from the studied prototype, point out that the simulations performed in naturally ventilated buildings is quite a complex task, due to the applications limitations, mainly owed to the complexity of air flow phenomena, the influence of comfort conditions in the surrounding areas and climate records. Lastly, regarding the use of the application DesignBuilder 1.2 in the present study, one may conclude that it is a good tool for computer simulations. However, it needs some adjustments to improve reliability in its use. There is a need for continued research, considering the dedication of users to the prototype, as well as the thermal charges of the equipment, in order to check sensitivity

Uma avaliação comparativa de estratégias de arranjos físicos para estaleiros de construção de embarcações metálicas de pequeno porte

The present study aims to analyse, in different levels of demand, what is the best layout strategy to adopt for the small metallic shipbuilding. To achieve this purpose, three simulation models are developed for analyze these production strategies under the positional, cellular and linear layouts. By the use of a simulation tool for compare the scenarios, Chwif and Medina (2010) and Law (2009)´s methodologies were adapted that includes three phases: conception, implementation and analysis. In conception real systems were represented by process mapping according to time, material resources and human resources variables required for each step of the production process. All of this information has been transformed in the cost variable. Data were collected from three different production systems, two located in Natal RN with cellular and positional layouts and one located in Belém-PA with linear layout. In the implementation phase, the conceptual models were converted in computacional models through the tool Rockwell Software Arena ® 13.5 and then validated. In the analysis stage the production of 960 ships in a year vessels were simulated for each layout noting that, for a production of until 80 units positional layout is the most recommended, between 81 and 288 units the cellular layout and more than 289 units the linear layout

Análise de desempenho de sistemas de comunicação sem-fio para monitoramento de unidade de produção de poços petrolíferos terrestres

The greater part of monitoring onshore Oil and Gas environment currently are based on wireless solutions. However, these solutions have a technological configuration that are out-of-date, mainly because analog radios and inefficient communication topologies are used. On the other hand, solutions based in digital radios can provide more efficient solutions related to energy consumption, security and fault tolerance. Thus, this paper evaluated if the Wireless Sensor Network, communication technology based on digital radios, are adequate to monitoring Oil and Gas onshore wells. Percent of packets transmitted with successful, energy consumption, communication delay and routing techniques applied to a mesh topology will be used as metrics to validate the proposal in the different routing techniques through network simulation tool NS-2

BRIDGE: uma ferramenta para o Design de Interfaces de Usuário baseada em especificações IMML

With hardware and software technologies advance, it s also happenning modifications in the development models of computational systems. New methodologies for user interface specification are being created with user interface description languages (UIDL). The UIDLs are a way to have a precise description in a language with more abstraction and independent of how will be implemented. A great problem is that even using these nowadays methodologies, we still have a big distance between the UIDLs and its design, what means, the distance between abstract and concrete. The tool BRIDGE (Interface Design Generator Environment) was created with the intention of being a linking bridge between a specification language (the Interactive Message Modeling Language IMML) and its implementation in Java, linking the abstract (specification) to the concrete (implementation). IMML is a language based on models, that allows the designer works in distinct abstraction levels, being each model a distinct abstraction level. IMML is a XML language, that uses the Semiotic Engineering concepts, that deals the computational system, with the user interface and its elements like a metacommunicative artifact, where these elements must to transmit a message to the user about what task must to be realized and the way to reach this goal. With BRIDGE, we intend to supply a lot of support to the design task, being the user interface prototipation the greater of them. BRIDGE allows the design becomes easier and more intuitive coming from an interface specification language

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++.

Contribuições para o processo de verificação de satisfatibilidade módulo teoria em Event-B

Event-B is a formal method for modeling and verification of discrete transition systems. Event-B development yields proof obligations that must be verified (i.e. proved valid) in order to keep the produced models consistent. Satisfiability Modulo Theory solvers are automated theorem provers used to verify the satisfiability of logic formulas considering a background theory (or combination of theories). SMT solvers not only handle large firstorder formulas, but can also generate models and proofs, as well as identify unsatisfiable subsets of hypotheses (unsat-cores). Tool support for Event-B is provided by the Rodin platform: an extensible Eclipse based IDE that combines modeling and proving features. A SMT plug-in for Rodin has been developed intending to integrate alternative, efficient verification techniques to the platform. We implemented a series of complements to the SMT solver plug-in for Rodin, namely improvements to the user interface for when proof obligations are reported as invalid by the plug-in. Additionally, we modified some of the plug-in features, such as support for proof generation and unsat-core extraction, to comply with the SMT-LIB standard for SMT solvers. We undertook tests using applicable proof obligations to demonstrate the new features. The contributions described can potentially affect productivity in a positive manner.

A methodology for building energy modelling and calibration in warm climates

PEDRINI, Aldomar; WESTPHAL, F. S.; LAMBERT, R.. A methodology for building energy modelling and calibration in warm climates. Building And Environment, Australia, n. 37, p.903-912, 2002. Disponível em: user=687335&_pii=S0360132302000513&_origin=search&_coverDate=09%2F30%2F2002&_sk=999629991&view=c&wchp=dGLzVtb-zSkzV&md5=f6342003b53dd1448e30308d082ba957&ie=/sdarticle.pdf>. Acesso em: 04 out. 2010.

Utilização de um aplicativo de simulação computacional na avaliação de desempenho térmico de protótipo de habitação de interesse social (his)

This Masters Degree dissertation seeks to make a comparative study of internal air temperature data, simulated through the thermal computer application DesignBuilder 1.2, and data registered in loco through HOBO® Temp Data Logger, in a Social Housing Prototype (HIS), located at the Central Campus of the Federal University of Rio Grande do Norte UFRN. The prototype was designed and built seeking strategies of thermal comfort recommended for the local climate where the study was carried out, and built with panels of cellular concrete by Construtora DoisA, a collaborator of research project REPESC Rede de Pesquisa em Eficiência Energética de Sistemas Construtivos (Research Network on Energy Efficiency of Construction Systems), an integral part of Habitare program. The methodology employed carefully examined the problem, reviewed the bibliography, analyzing the major aspects related to computer simulations for thermal performance of buildings, such as climate characterization of the region under study and users thermal comfort demands. The DesignBuilder 1.2 computer application was used as a simulation tool, and theoretical alterations were carried out in the prototype, then they were compared with the parameters of thermal comfort adopted, based on the area s current technical literature. Analyses of the comparative studies were performed through graphical outputs for a better understanding of air temperature amplitudes and thermal comfort conditions. The data used for the characterization of external air temperature were obtained from the Test Reference Year (TRY), defined for the study area (Natal-RN). Thus the author also performed comparative studies for TRY data registered in the years 2006, 2007 and 2008, at weather station Davis Precision Station, located at the Instituto Nacional de Pesquisas Espaciais INPE-CRN (National Institute of Space Research), in a neighboring area of UFRN s Central Campus. The conclusions observed from the comparative studies performed among computer simulations, and the local records obtained from the studied prototype, point out that the simulations performed in naturally ventilated buildings is quite a complex task, due to the applications limitations, mainly owed to the complexity of air flow phenomena, the influence of comfort conditions in the surrounding areas and climate records. Lastly, regarding the use of the application DesignBuilder 1.2 in the present study, one may conclude that it is a good tool for computer simulations. However, it needs some adjustments to improve reliability in its use. There is a need for continued research, considering the dedication of users to the prototype, as well as the thermal charges of the equipment, in order to check sensitivity

Precificação de energia eólica offshore no Brasil

Offshore wind power emits low amounts of gases, is renewable and has better performance than onshore due to its greater stability and higher wind power density, less visual and noise impact, among others. Brazil has a high capacity of generation, but has not yet developed any offshore projects. High costs are a strong impediment. This study is an effort towards pricing offshore resources through Livelized Cost of Energy - LCOE, which represents the minimum return to cover the costs of development, production and maintenance of a wind project. Initially LCOE was calculated for all Brazilian onshore wind farms listed at Bloomberg New Energy Finance R○, accounting for 71 farms. Then hypothetical offshore wind farms were created from the onshore farms, tripling the cost of generation, which is consistent with the literature, and estimating the offshore energy for two locations off the Brazilian coast using satellite data extracted from National Oceanic and Atmospheric Administration. The results demonstrate that offshore resources have the potential to significantly reduce the energy price due to the better performance of the wind at sea

Teoria de carteiras e a alocação de parques eólicos offshore

The consumption of energy on the planet is currently based on fossil fuels. They are responsible for adverse effects on the environment. Renewables propose solutions for this scenario, but must face issues related to the capacity of the power supply. Wind energy offshore emerging as a promising alternative. The speed and stability are greater winds over oceans, but the variability of these may cause inconvenience to the generation of electric power fluctuations. To reduce this, a combination of wind farms geographically distributed was proposed. The greater the distance between them, the lower the correlation between the wind velocity, increasing the likelihood that together achieve more stable power system with less fluctuations in power generation. The efficient use of production capacity of the wind park however, depends on their distribution in marine environments. The objective of this research was to analyze the optimal allocation of wind farms offshore on the east coast of the U.S. by Modern Portfolio Theory. The Modern Portfolio Theory was used so that the process of building portfolios of wind energy offshore contemplate the particularity of intermittency of wind, through calculations of return and risk of the production of wind farms. The research was conducted with 25.934 observations of energy produced by wind farms 11 hypothetical offshore, from the installation of 01 simulated ocean turbine with a capacity of 5 MW. The data show hourly time resolution and covers the period between January 1, 1998 until December 31, 2002. Through the Matlab R software, six were calculated minimum variance portfolios, each for a period of time distinct. Given the inequality of the variability of wind over time, set up four strategies rebalancing to evaluate the performance of the related portfolios, which enabled us to identify the most beneficial to the stability of the wind energy production offshore. The results showed that the production of wind energy for 1998, 1999, 2000 and 2001 should be considered by the portfolio weights calculated for the same periods, respectively. Energy data for 2002 should use the weights derived from the portfolio calculated in the previous time period. Finally, the production of wind energy in the period 1998-2002 should also be weighted by 1/11. It follows therefore that the portfolios found failed to show reduced levels of variability when compared to the individual production of wind farms hypothetical offshore

Reconfiguração dinâmica de estratégias distribuídas em dispositivos foundation fieldbus para a otimização de processos na indústria do petróleo

The petrochemical industry has as objective obtain, from crude oil, some products with a higher commercial value and a bigger industrial utility for energy purposes. These industrial processes are complex, commonly operating with large production volume and in restricted operation conditions. The operation control in optimized and stable conditions is important to keep obtained products quality and the industrial plant safety. Currently, industrial network has been attained evidence when there is a need to make the process control in a distributed way. The Foundation Fieldbus protocol for industrial network, for its interoperability feature and its user interface organized in simple configuration blocks, has great notoriety among industrial automation network group. This present work puts together some benefits brought by industrial network technology to petrochemical industrial processes inherent complexity. For this, a dynamic reconfiguration system for intelligent strategies (artificial neural networks, for example) based on the protocol user application layer is proposed which might allow different applications use in a particular process, without operators intervention and with necessary guarantees for the proper plant functioning

Compressão de Imagens Usando a Função de Peano e a Transformada Wavelet 1D

In this work, spoke about the importance of image compression for the industry, it is known that processing and image storage is always a challenge in petrobrás to optimize the storage time and store a maximum number of images and data. We present an interactive system for processing and storing images in the wavelet domain and an interface for digital image processing. The proposal is based on the Peano function and wavelet transform in 1D. The storage system aims to optimize the computational space, both for storage and for transmission of images. Being necessary to the application of the Peano function to linearize the images and the 1D wavelet transform to decompose it. These applications allow you to extract relevant information for the storage of an image with a lower computational cost and with a very small margin of error when comparing the images, original and processed, ie, there is little loss of quality when applying the processing system presented . The results obtained from the information extracted from the images are displayed in a graphical interface. It is through the graphical user interface that the user uses the files to view and analyze the results of the programs directly on the computer screen without the worry of dealing with the source code. The graphical user interface, programs for image processing via Peano Function and Wavelet Transform 1D, were developed in Java language, allowing a direct exchange of information between them and the user