检索结果-内蒙古大学图书馆

Euromicro Symposium on Digital System Design

作者： Alexandre S. Nery Nadia Nedjah Felipa M.G. Franca Lech Jozwiak LAM-Computer Architecture and Microelectronics Laboratory Systems Engineering and Computer Science Program COPPE Universidade Federal do Rio de Janeiro Brazil Department of Electrical Engineering-Electronic Systems Eindhoven University of Technology Netherlands Universidade do Estado do Rio de Janeiro Rio de Janeiro RJ BR

The Ray Tracing rendering algorithm can produce high-fidelity images of 3-D scenes, including shadow effects, as well as reflections and transparencies. This is currently done at a processing speed of at most 30 frames per second. Therefore, actual implementations of the algorithm are not yet suitable for interactive real-time rendering, which is required in games and virtual reality based applications. Fortunately, the algorithm allows for massive parallelization of its computations. In this paper, we present a parallel architecture for ray tracing based on a uniform spatial subdivision of the scene and exploiting an embedded computation of ray-triangle intersections. This approach allows for a significant acceleration of intersection computations, as well as, a reduction of the total number of the required intersections checks. Furthermore, it allows for these checks to be performed in parallel and in advance for each ray. In this paper we discuss and analyze an ASIP-based implementation using FPGAs and a GPGPU-based parallel implementation of the proposed architecture. The performance of both implementations are reported and compared.

关键词： Ray tracing Graphics processing unit Instruction sets Computer architecture Registers Image color analysis Hardware

来源：评论

学校读者我要写书评

暂无评论

Hardware Reuse in Modern Application-Specific Processors and Accelerators

Hardware Reuse in Modern Application-Specific Processors and...

引用

Euromicro Symposium on Digital System Design

作者： Alexandre S. Nery Lech Jozwiak Menno Lindwer Mauro Cocco Nadia Nedjah Felipe M.G. Franca LAM-Computer Architecture and Microelectronics Laboratory Systems Engineering and Computer Science Program COPPE Universidade Federal do Rio de Janeiro Brazil Department of Electrical Engineering-Electronic Systems Eindhoven University of Technology Netherlands Silicon Hive-Intel UMG Netherlands Department of Electronics Engineering and Telecommunications-Faculty of Engineering Universidade do Estado do Rio de Janeiro Brazil

Effective exploitation of the application-specific parallel patterns and computation operations through their direct implementation in hardware is the base for construction of high-quality application-specific (re-)configurable application specific instruction set processors (ASIPs) and hardware accelerators for modern highly-demanding applications. Although it receives a lot of attention from the researchers and practitioners, a very important problem of hardware reuse in ASIP and accelerator synthesis is clearly underestimated and does not get enough attention in the published research. This paper is an effect of an industry and academic collaborative research. It analyses the problem of hardware sharing, shows its high practical relevance, as well as a big influence of hardware sharing on the major circuit and system parameters, and its importance for the multi-objective optimization and tradeoff exploitation. It also demonstrates that the state-of-the-art synthesis tools do not sufficiently address this problem and gives several guidelines related to enhancement of the hardware reuse.

关键词： Hardware Resource management Computer architecture Optimization program processors Adders Delay

来源：评论

学校读者我要写书评

暂无评论

Nineteen multilevel asymmetric cascaded with an improved modulation strategy

Nineteen multilevel asymmetric cascaded with an improved mod...

引用

2010 IEEE International Symposium on Industrial Electronics, ISIE 2010

作者： Encarnação, Lucas Frizera Monteiro, Luis Fernando Correa Aredes, Mauricio Electrical Engineering Program COPPE/UFRJ Power Electronic Laboratory Rio de Janeiro Brazil

ISBN: (纸本)9781424463916

The increase of the power demand and the technology modernization of industrial processes, results in the rapid expansion of electric-electronic equipment susceptible to poor power quality in medium voltage distribution systems. Therefore, problems related to energy quality, which in the last decades were responsible only for annoying situations and small losses to residential and commercial costumers, now cause damage to equipments and high financial losses to industries, especially those that use complex industrial processes. The necessity of a better energy quality for industry encourages the transition of the custom power equipments, typically used in low voltage systems, to work in medium voltage systems. This recent interest has been instigating researches from the power-electronics society in multilevel power converter techniques, which present a viable and efficient alternative to control the power flow in medium voltage systems. In this context, this article presents a nineteen multilevel distribution static synchronous compensator (DSTATCOM), with minimum active components, to improve the power quality in industrial installations. Simulations and experimental results show the proper performance of the proposed multilevel converter. © 2010 IEEE.

关键词： Power quality

来源：评论

学校读者我要写书评

暂无评论

Robust diagnosability of discrete event systems subject to intermittent sensor failures

Robust diagnosability of discrete event systems subject to i...

引用

作者： Carvalho, Lilian Kawakami Basilio, João Carlos Moreira, Marcos Vicente Federal University of Rio de Janeiro COPPE - Electrical Engineering Program 21949-900 Rio de Janeiro RJ Brazil

ISBN: (纸本)9783902661791

The modeling of physical systems using discrete event models assumes that a set of sensors always report the event occurrences correctly. However, bad sensor operation can result in loss of observability of the events associated with the malfunctioning sensors. If one or more sensors fail, it may be possible that either the diagnoser stands still or provide wrong information on the fault occurrence. This paper assumes that intermittent sensor failures may occur and deals with the problem of fault diagnosis in the presence of intermittent sensor failures. To this end, an automaton model for intermittent sensor failures based on a newly proposed language operation (language dilation) is presented in the paper. Necessary and sufficient conditions for robust diagnosability against intermittent sensor failure are also given in the paper. The development of a robust diagnoser that copes with intermittent sensor failures is another contribution of the paper.

关键词： Failure analysis

来源：评论

学校读者我要写书评

暂无评论

Fully automatic Bayesian neural forecaster - NN GC1

Fully automatic Bayesian neural forecaster - NN GC1

引用

2010 6th IEEE World Congress on Computational Intelligence, WCCI 2010 - 2010 International Joint Conference on Neural Networks, IJCNN 2010

作者： Ferreira, Vitor Hugo Alves Da Silva, Alexandre P. Electrical Engineering Department Niterói RJ 24210-240 Brazil COPPE/UFRJ Electrical Engineering Graduate Program Power Systems Laboratory P.O. Box 68504 Rio de Janeiro RJ 21945-972 Brazil

ISBN: (纸本)9781424469178

This paper combines several techniques to generate a fully data-driven forecasting model. Input selection is performed, without user intervention, by applying chaos theory and Bayesian inference. Afterwards, neural network models are estimated, without cross-validation, relying on data partitioning and Bayesian regularization for complexity control. Automatic data clustering has been used for data partitioning. The proposed forecasting model has been tested with datasets provided by the competition organizers. © 2010 IEEE.

关键词： Chaos theory

来源：评论

学校读者我要写书评

暂无评论

Active contours without edges applied to breast lesions on ultrasound

Active contours without edges applied to breast lesions on u...

引用

作者： Gómez, W. Infantosi, A.F.C. Leija, L. Pereira, W.C.A. Department of Electrical Engineering CINVESTAV-IPN Mexico D.F. Mexico Biomedical Engineering Program COPPE/UFRJ Cidade Universitária Horácio Macedo Ave. 2030 Rio de Janeiro Brazil

ISBN: (纸本)9783642130380

A computerized lesion segmentation technique for breast ultrasound images is proposed. It uses a deformable model based on active contours without edges. The performance of this technique was accessed by comparing the resulting contours of 50 ultrasonographies with those manually delineated by two radiologists. For the boundary, the error metrics used were the Hausdorff distance (HD) and the mean absolute distance (MD). The error area was assessed by using the percentage of false positive (FP), false negative (FN), and true positive (TP) pixels. The results were HD = 8.76±6.04, MD = 2.78±1.20, FP = 4.98±3.83, FN = 16.19±6.85, and TP = 83.86±6.75. These findings indicate that the proposed technique was capable to reach high detailed contours. © 2010 International Federation for Medical and Biological engineering.

关键词： Image segmentation

来源：评论

学校读者我要写书评

暂无评论

Time-varying channel characterization based on SVM under the impulsive noise presence

Time-varying channel characterization based on SVM under the...

引用

14th Annual International Symposium on Power Line Communications and its Applications, IEEE ISPLC 2010

作者： Dias, João De Campos, Fabrício P. V. De Campos, Marcello L. R. Pinto, Ernesto L. Ribeiro, Moisés V. Electrical Engineering Program COPPE/Federal University of Rio de Janeiro 68504 21945-970 Rio de Janeiro RJ Brazil Electrical Engineering Department Military Institute of Engineering 22290-270 Rio de Janeiro RJ Brazil Electrical Engineering Department Federal University of Juiz de Fora 36036-900 Juiz de Fora MG Brazil

ISBN: (纸本)9781424450107

The purpose of this work is to present an off-line technique for characterization of time-varying power line communications channels in the presence of additive impulsive noise when they are used for broadband data transmission. We propose and analyze a channel estimation technique based on Support Vector Machine (SVM). Simulation results reveal that the proposed method is more robust to impulsive noise and has better convergence rate for time-varying channels when compared to classic techniques like least squares (LS). ©2010 IEEE.

关键词： Support vector machines

来源：评论

学校读者我要写书评

暂无评论

Nineteen multilevel asymmetric cascaded with an improved modulation strategy

Nineteen multilevel asymmetric cascaded with an improved mod...

引用

IEEE International Symposium on Industrial Electronics (ISIE)

作者： Lucas Frizera Encarnação Luis Fernando Correa Monteiro Mauricio Aredes Electrical Engineering Program Power Electronic Laboratory COPPE UFRJ Rio de Janeiro Brazil Electrical Engineering Program Power Electronic Laboratory Brazil

关键词： Converters Voltage control Pulse width modulation Capacitors Reactive power Power factor correction

来源：评论

学校读者我要写书评

暂无评论

Robust diagnosability of discrete event systems subject to intermittent sensor failures

引用

IFAC Proceedings Volumes 2010年第12期43卷 84-89页

作者： Lilian Kawakami Carvalho João Carlos Basilio Marcos Vicente Moreira Federal University of Rio de Janeiro COPPE - Electrical Engineering Program 21949-900 Rio de Janeiro R.J. Brasil

关键词： Discrete event systems fault diagnosis intermittent sensor failures robust diagnosability

来源：评论

学校读者我要写书评

暂无评论

Semiautomatic contour detection of breast lesions in ultrasonic images with morphological operators and average radial derivative function

引用

Physics Procedia 2010年第1期3卷 373-380页

作者： W. Gómez L. Leija W.C.A. Pereira A.F.C. Infantosi Department of Electrical Engineering CINVESTAV-IPN Av. IPN 2508 Mexico City 07000 Mexico Biomedical Engineering Program COPPE/UFRJ Av. Horacio Macedo 2030 Rio de Janeiro 21941-914 Brazil

This work presents a computerized lesion segmentation technique on breast ultrasound images. There were applied known techniques such as morphological filtering, Watershed transformation and average radial derivative function. To evaluate the performance of the proposed method, two protocols were established. For the first, the resulting segmentation contours were compared with those of 24 gold standard simulated ultrasound-like images, and, for second, with 36 breast US images manually delineated by two senior radiologists. Further, two evaluation parameters were used: the percentage of coincidence (CP) and the proportional distance (PD). The former indicates the similarity between contours, while the latter express the dissimilarity. The accuracy of the proposed method was evaluated by considering images with CP>80% and PD<10% as adequately delineated. It was higher than 80% for real images and higher than 88% for simulated images.

关键词： Average radial derivative Breast ultrasound Morphological operators Segmentation

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：