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63.
在悬浮控制系统设计中,通常用到悬浮间隙的变化速度,如何获取这一信号是一个非常重要的问题。以单电磁铁为对象,根据悬浮系统的模型,提出了一种通过互补滤波器获得速度的方法;详细分析了不同的速度获取方式在考虑轨道随机扰动和列车运行于竖曲线段以及考虑轨道弹性等几种情况下对系统的影响。仿真结果表明,该方法能很好地实现常规方法的性能折衷,为克服轨道扰动和解决车轨共振问题提供了新的思路。 相似文献
64.
Modeling and Managing Interactions among Business Processes 总被引:3,自引:0,他引:3
Most workflow management systems (WfMSs) only support the separate andindependent execution of business processes. However, processes often needto interact with each other, in order to synchronize the execution of theiractivities, to exchange process data, to request execution of services, orto notify progresses in process execution. Recent market trends also raisethe need for cooperation and interaction between processes executed in differentorganizations, posing additional challenges. In fact, in order to reduce costsand provide better services, companies are pushed to increase cooperation and toform virtual enterprises, where business processes span across organizationalboundaries and are composed of cooperating workflows executed in differentorganizations. Workflow interaction in a cross-organizational environment iscomplicated by the heterogeneity of workflow management platforms on top ofwhich workflows are defined and executed and by the different and possiblycompeting business policies and business goals that drive process executionin each organization.In this paper we propose a model and system that enable interactionbetween workflows executed in the same or in different organizations. Weextend traditional workflow models by allowing workflows to publish andsubscribe to events, and by enabling the definition of points in the processexecution where events should be sent or received. Event notifications aremanaged by a suitable event service that is capable of filtering andcorrelating events, and of dispatching them to the appropriate targetworkflow instances. The extended model can be easily mapped onto anyworkflow model, since event specific constructs can be specified by means ofordinary workflow activities, for which we provide the implementation. Inaddition, the event service is easily portable to different platforms, anddoes not require integration with the WfMS that supports the cooperatingworkflows. Therefore, the proposed approach is applicable in virtually anyenvironment and is independent on the specific platform adopted 相似文献
65.
Algorithmic and architectural design for real-time and power-efficient Retinex image/video processing 总被引:1,自引:1,他引:0
Sergio Saponara Luca Fanucci Stefano Marsi Giovanni Ramponi 《Journal of Real-Time Image Processing》2007,1(4):267-283
This paper presents novel algorithmic and architectural solutions for real-time and power-efficient enhancement of images
and video sequences. A programmable class of Retinex-like filters, based on the separation of the illumination and reflectance
components, is proposed. The dynamic range of the input image is controlled by applying a suitable non-linear function to
the illumination, while the details are enhanced by processing the reflectance. An innovative spatially recursive rational
filter is used to estimate the illumination. Moreover, to improve the visual quality results of two-branch Retinex operators
when applied to videos, a novel three-branch technique is proposed which exploits both spatial and temporal filtering. Real-time
implementation is obtained by designing an Application Specific Instruction-set Processor (ASIP). Optimizations are addressed
at algorithmic and architectural levels. The former involves arithmetic accuracy definition and linearization of non-linear
operators; the latter includes customized instruction set, dedicated memory structure, adapted pipeline, bypasses, custom
address generator, and special looping structures. The ASIP is synthesized in standard-cells CMOS technology and its performances
are compared to known Digital signal processor (DSP) implementations of real-time Retinex filters. As a result of the comparison,
the proposed algorithmic/architectural design outperforms state-of-art Retinex-like operators achieving the best trade-off
between power consumption, flexibility, and visual quality.
Sergio Saponara is a Research Scientist and Assistant Professor at the University of Pisa. He was born in Bari, Italy, in 1975. He received the Electronic Engineering degree cum laude and the Ph.D. in Information Engineering, both from Pisa University, in 1999 and 2003, respectively. Since 2001 he collaborates with Consorzio Pisa Ricerche, Italy and in 2002 he was with IMEC, Belgium as Marie Curie research fellow. His research and teaching interests include electronic circuits and systems for multimedia, telecom and automation. He co-authored more than 40 papers including journals, conferences and patents. Luca Fanucci is Associate Professor of Microelectronics at the University of Pisa. He was born in Montecatini, Italy, in 1965. He received the Doctor Engineer degree and the Ph.D. in Electronic Engineering from the University of Pisa in 1992 and 1996, respectively. From 1992 to 1996, he was with the European Space Agency's Research and Technology Center, Noordwijk, The Netherlands, and from 1996 to 2004 he was a Research Scientist of the Italian National Research Council in Pisa. His research interests include design technologies for integrated circuits and systems, with emphasis on system-level design, hardware/software co-design and low-power. He co-authored more than 100 journal/conference papers and holds more than 10 patents. Stefano Marsi was born in Trieste, Italy, in 1963. He received the Doctor Engineer degree in Electronic Engineering (summa cum laude) in 1990 and the Ph.D. degree in 1994. Since 1995 he has held the position of researcher in the Department of Electronics at the University of Trieste where he is the teacher of courses in electronic field. His research interests include non-linear operators for image and video processing and their realization through application specific electronics circuits. He is author or co-author of more than 40 papers in international journals, proceedings of international conferences or contributions in books. Giovanni Ramponi is Professor of Electronics at the Department of Electronics of the University of Trieste, Italy. His research interests include nonlinear digital signal processing, and the enhancement and feature extraction in images and image sequences. Prof. Ramponi has been an Associate Editor of the IEEE Signal Processing Letters and of the IEEE Transactions on Image Processing; presently is an AE of the SPIE Journal of Electronic Imaging. He has participated in various EU and National Research Projects. He is the co-inventor of various pending international patents and has published more than 140 papers in international journals and conference proceedings, and as book chapters. Prof. Ramponi contributes to several undergraduate and graduate courses on digital signal processing. 相似文献
Giovanni RamponiEmail: |
Sergio Saponara is a Research Scientist and Assistant Professor at the University of Pisa. He was born in Bari, Italy, in 1975. He received the Electronic Engineering degree cum laude and the Ph.D. in Information Engineering, both from Pisa University, in 1999 and 2003, respectively. Since 2001 he collaborates with Consorzio Pisa Ricerche, Italy and in 2002 he was with IMEC, Belgium as Marie Curie research fellow. His research and teaching interests include electronic circuits and systems for multimedia, telecom and automation. He co-authored more than 40 papers including journals, conferences and patents. Luca Fanucci is Associate Professor of Microelectronics at the University of Pisa. He was born in Montecatini, Italy, in 1965. He received the Doctor Engineer degree and the Ph.D. in Electronic Engineering from the University of Pisa in 1992 and 1996, respectively. From 1992 to 1996, he was with the European Space Agency's Research and Technology Center, Noordwijk, The Netherlands, and from 1996 to 2004 he was a Research Scientist of the Italian National Research Council in Pisa. His research interests include design technologies for integrated circuits and systems, with emphasis on system-level design, hardware/software co-design and low-power. He co-authored more than 100 journal/conference papers and holds more than 10 patents. Stefano Marsi was born in Trieste, Italy, in 1963. He received the Doctor Engineer degree in Electronic Engineering (summa cum laude) in 1990 and the Ph.D. degree in 1994. Since 1995 he has held the position of researcher in the Department of Electronics at the University of Trieste where he is the teacher of courses in electronic field. His research interests include non-linear operators for image and video processing and their realization through application specific electronics circuits. He is author or co-author of more than 40 papers in international journals, proceedings of international conferences or contributions in books. Giovanni Ramponi is Professor of Electronics at the Department of Electronics of the University of Trieste, Italy. His research interests include nonlinear digital signal processing, and the enhancement and feature extraction in images and image sequences. Prof. Ramponi has been an Associate Editor of the IEEE Signal Processing Letters and of the IEEE Transactions on Image Processing; presently is an AE of the SPIE Journal of Electronic Imaging. He has participated in various EU and National Research Projects. He is the co-inventor of various pending international patents and has published more than 140 papers in international journals and conference proceedings, and as book chapters. Prof. Ramponi contributes to several undergraduate and graduate courses on digital signal processing. 相似文献
66.
化妆品防晒剂的研究进展及其安全性问题(续前) 总被引:3,自引:0,他引:3
一类重要的且光稳定的UVA紫外线吸收剂是苯三唑邻位羟基取代的化合物。这类紫外线吸收剂主要吸收长波段的紫外线UVA,但其吸收效率或称摩尔消光系数要比二苯甲酰甲烷类化合物如Avobenzone低。由于这类苯三唑化合物中形成的氮-氢(N-H) 相似文献
67.
杨秀朋 《重庆科技学院学报(自然科学版)》2012,14(5):154-157
介绍FIR滤波器的基本原理以及满足线性相位的条件,阐述了FIR滤波器的生成.从MATLAB得到的滤波器实现了在嵌入式中的移植,并进行了计算优化.通过对含有噪声的数据处理结果表明,该方法在工程实践中能满足要求. 相似文献
68.
Multiple human tracking in high-density crowds 总被引:1,自引:0,他引:1
In this paper, we introduce a fully automatic algorithm to detect and track multiple humans in high-density crowds in the presence of extreme occlusion. Typical approaches such as background modeling and body part-based pedestrian detection fail when most of the scene is in motion and most body parts of most of the pedestrians are occluded. To overcome this problem, we integrate human detection and tracking into a single framework and introduce a confirmation-by-classification method for tracking that associates detections with tracks, tracks humans through occlusions, and eliminates false positive tracks. We use a Viola and Jones AdaBoost detection cascade, a particle filter for tracking, and color histograms for appearance modeling. To further reduce false detections due to dense features and shadows, we introduce a method for estimation and utilization of a 3D head plane that reduces false positives while preserving high detection rates. The algorithm learns the head plane from observations of human heads incrementally, without any a priori extrinsic camera calibration information, and only begins to utilize the head plane once confidence in the parameter estimates is sufficiently high. In an experimental evaluation, we show that confirmation-by-classification and head plane estimation together enable the construction of an excellent pedestrian tracker for dense crowds. 相似文献
69.
《国际计算机数学杂志》2012,89(2):254-263
This paper focuses on the construction and properties of spline dyadic wavelet that equals its reconstruction wavelet. A general construction method of finite spline dyadic low-pass and high-pass filters is given. It proves that finite spline dyadic low-pass filters are symmetric about 0 or 1/2, but there are no finite spline high-pass filters possessing symmetry with respect to 0 or 1/2. It further shows that there exist infinite spline high-pass filters possessing symmetry with respect to 0 or 1/2, which can be constructed. Their energy is concentrated and so finite symmetric spline dyadic wavelet filter that equals its reconstruction filter can be obtained approximately. Construction examples for quadratic and cubic spline dyadic wavelet filters are given. 相似文献
70.
基于Matlab/Simulink平台,给出了滚升余弦滤波器和眼图的具体实现方法及流程。以FIR滤波器为基本模块构造了滚升余弦滤波器基本模型,并通过改变滚降系数对滚升余弦滤波器的性能作出分析,验证了方案的可行性。 相似文献