DECOM - Trabalhos apresentados em eventos
URI permanente para esta coleçãohttp://www.hml.repositorio.ufop.br/handle/123456789/581
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Resultados da Pesquisa
Item An embedded converter from RS232 to universal serial bus.(2001) Zuquim, Ana Luiza de Almeida Pereira; Coelho Júnior, Claudionor José Nunes; Fernandes, Antônio Otávio; Oliveira, Marcos Pêgo; Tavares, Andréa IabrudiUniversal Serial Bus (USB) is a new personal computer interconnection protocol, developed to make the connection of peripheral devices to a computer easier and more efficient. It reduces the cost for the enduser, improves communication speed and supports simultaneous attachment of multiple devices (up to 127). RS232, in another hand, was designed to single device connection, but is one of the most used communication protocols. An embedded converter from RS232 to USB is very interesting, since it would allow serial-based devices to experience USB advantages without major changes. This work describes the specification and development of such converter and it is also a useful guide for implementing other USB devices. The converter specification was based on Engetron UPS’ serial communication requirements and its implementation uses a Cypress microcontroller with USB support.Item Efficient allocation of verification resources using revision history information.(2008) Nacif, José Augusto Miranda; Silva, Thiago; Tavares, Andréa Iabrudi; Fernandes, Antônio Otávio; Coelho Júnior, Claudionor José NunesVerifying large industrial designs is getting harder each day. he current verification methodologies are not able to guarantee bug free designs. Some recurrent questions during a design verification are: Which modules are most likely to contain undetected bugs? In wich modules the verification team should concentrate their effort? This information is very useful, because it is better to start verifying the most bug-prone modules. In this work we present a novel approach to answer these questions. In order to identify these bug rone modules the revision history of the design is used. Using information of an academic experiment, we demonstrate that there is a close between bugs/changes history and future bugs. Our results show that allocating modules for verification based on bugs/changes leaded to the coverage of 91.67% of future bugs, while random based strategy covered only 37.5% of the future work mainly focused in software engineering techniques to bugs.Item System-level partitioning with uncertainty.(1999) Albuquerque, Jones; Coelho Júnior, Claudionor José Nunes; Cavalcanti, Carlos Frederico Marcelo da Cunha; Silva Júnior, Diógenes Cecílio da; Fernandes, Antônio OtávioSeveral models and algorithms have been proposed in the past to generate HW/SW components for system-level designs. However, they were focused on a single designer who had a throughout knowledge of the design. In other words, the decision trade-offs were simplified to a stand-alone developer who did not have to consider individual skills, concurrent development for portions of the design, risk analysis for time-to-market development, nor team load and assignment. In this paper, we propose a design management approach associated with a partitioning methodology to deal with the concurrent design problems of system-level specifications. This methodology allows one to incorporate the uncertainties related to development at the very early stages of the design, and to follow up during the development of a final product.Item On the use data reduction algorithms for real-time Wireless Sensor Networks.(2007) Aquino, André Luiz Lins de; Figueiredo, Carlos Maurício Seródio; Nakamura, Eduardo Freire; Loureiro, Antônio Alfredo Ferreira; Fernandes, Antônio Otávio; Coelho Júnior, Claudionor José NunesThis work presents the design of real time applications for Wireless Sensor Networks (WSNs) by using analgorithm based on data stream to process the sensor data. The proposed algorithm is based on sampling techniques applied to data histograms created from original data stream sac quired by sensor nodes. As a result, the algorithm provides a sample of log n item store present the original data stream of n elements. In this work, we show how to use the data reduction algorithmin real-time WSN design.Item Data stream based algorithms for wireless sensor network applications(2007) Aquino, André Luiz Lins de; Figueiredo, Carlos Maurício Seródio; Nakamura, Eduardo Freire; Buriol, Luciana Salete; Loureiro, Antônio Alfredo Ferreira; Fernandes, Antônio Otávio; Coelho Júnior, Claudionor José NunesA wireless sensor network (WSN) is energy con-strained, and the extension of its lifetime is one of the most important issues in its design. Usually, a WSN collects a large amount of data from the environment. In contrast to the conventional remote sensing – based on satellites that collect large images, sound files, or specific scientific data – sensor networks tend to generate a large amount of sequential small and tuple-oriented data from several nodes, which constitutes data streams. In this work, we propose and evaluate two algorithms based on data stream, which use sampling and sketch techniques, to reduce data traffic in a WSN and, consequently, decrease the delay and energy consumption. Specifically, the sampling solution, provides a sample of only log n items to represent the original data of n elements. Despite of the reduction, the sampling solution keeps a good data quality. Simulation results reveal the efficiency of the proposed meth-ods by extending the network lifetime and reducing the delay without loosing data representativeness. Such a technique can be very useful to design energy-efficient and time-constrained sensor networks if the application is not so dependent on the data precision or the network operates in an exception situation (e.g., there are few resources remaining or there is an urgent situation)