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A rate based congestion control algorithm in networks with coexisting unicast and multicast sessions

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Journal of university of Science and technology Beijing 2003年第3期10卷 66-72页

作者： Qian Dong and Jianying Xieschool of electronics & information technology, shanghai jiaotong university, shanghai 200030, china Sch. of Electron. and Info. Technol. Shanghai Jiaotong Univ. Shanghai 200030 China

The optimal rate control problem in networks with unicast and multiratemulticast sessions is investigated. A penalty function approach is used to solve a convex programformulation of this problem, and then a heuristic rate control algorithm is derived. The algorithmis distributed, and suitable both for source-driven unicast sessions and receiver-driven multicastsessions. To obtain practical viability, the computational burden on core routers as well asend-hosts is kept very low, also is the overhead of network congestion feedback. Simulation resultsshow that the algorithm guarantees TCP (Transmission Control Protocol)-based unicast sessionscoexisting with multirate multicast sessions in a fair and friendly manner. It is also shown thatvarious fairness criteria of resource allocation could be achieved by choosing appropriate utilityfunctions, and resource-utilizing efficiencies would be likewise different.

关键词： multicast unicast congestion control rate control fairness

Experts' Knowledge Fusion in Model-Based Diagnosis Based on Bayes Networks

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Journal of Systems Engineering and electronics 2003年第2期14卷 25-30页

作者： Deng Yong & Shi Wenkang school of electronics & information technology, shanghai jiaotong university, shanghai 200030, P. R. china school of electronics & information technology Shanghai Jiaotong University Shanghai 200030 P. R. China

In previous researches on a model-based diagnostic system, the components are assumed mutually independent. Howerver , the assumption is not always the case because the information about whether a component is faulty or not usually influences our knowledge about other components. Some experts may draw such a conclusion that 'if component m 1 is faulty, then component m 2 may be faulty too'. How can we use this experts' knowledge to aid the diagnosis? Based on Kohlas's probabilistic assumption-based reasoning method, we use Bayes networks to solve this problem. We calculate the posterior fault probability of the components in the observation state. The result is reasonable and reflects the effectiveness of the experts' knowledge.

关键词： Model-based diagnosis Experts' knowledge Probabilistic assumption-based reasoning Bayes networks.

Lie bialgebras of generalized Witt type

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Science china Mathematics 2006年第4期49卷 533-544页

作者： SONG Guang’ai & SU Yucai College of Mathematics and information Science, Shandong Institute of Business and technology, Yantai 264005, china Department of Mathematics, university of Science and technology of china, Hefei 230026, china Department of Mathematics, shanghai jiaotong university, shanghai 200240, china College of Mathematics information Science Shandong Institute of Business technology Yantai 264005 China Department of Mathematics University of Science technology of china Hefei 230026 China Department of Mathematics Shanghai Jiaotong University Shanghai 200240 China

In this paper, all Lie bialgebra structures on the Lie algebras of generalized Witt type are considered. It is proved that, for any Lie algebra W of generalized Witt type, all Lie bialgebras on W are the coboundary triangular Lie bialgebras. As a by-product, it is also proved that the first cohomology group H1(W, W(?)W) is trivial.

关键词： Lie bialgebras, Yang-Baxter equation, Lie algebra of generalized Witt type.

Pan-sharpening:a fast variational fusion approach

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Science china(information Sciences) 2012年第3期55卷 615-625页

作者： ZHOU ZeMing1, LI YuanXiang2 , SHI HanQing1, MA Ning1 & SHEN Ji2 1Institute of Meteorology, PLA university of Science and technology, Nanjing 211101, china 2school of Aeronautics and Astronautics, shanghai jiaotong university, shanghai 200240, china 1. Institute of Meteorology PLA University of Science and Technology Nanjing 211101 China2. School of Aeronautics and Astronautics Shanghai JiaoTong University Shanghai 200240 China

A fast variational fusion model based on partial differential equations (PDEs) is presented for pansharpening. The functional framework consists of several energy terms. The gradient energy term is created by calculating the gradient vector field of the panchromatic image and the geometry of the pan is injected into the multi-spectral bands. The radiometric reduction energy term and the channel correlation energy term are defined to decrease the radiometric distortion and preserve the correlation of multi-spectral channels while enforcing the inter-bands coherence. Inspired by the shock-filtering model, an inverse diffusion term for image enhancement is put to PDEs which are deduced by minimizing the energy functional. In comparison with the state-of-the-art fusion approaches based on `a trous wavelet and non-sampled contourlet, our model can obtain the fused image with a high spatial or spectral quality by adjusting the weight coefficients of the energy terms. It can also achieve a rather good trade-off between the spatial resolution improvement and the spectral quality preserving. Our model's computational complexity for one time step is only O(N).

关键词： remote sensing image pan-sharpening energy functional fast variational fusion

Spatial continuity incorporated multi-attribute fuzzy clustering algorithm for blood vessels segmentation

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Science china(information Sciences) 2010年第4期53卷 752-759页

作者： HAO JuTao1*, ZHAO JingJing2 & LI MingLu3 1school of Optical-Electrical and Computer Engineering, university of shanghai for Science and technology, shanghai 200093, china 2Department of Electrical Engineering, shanghai university of Electric Power, shanghai 200090, china 3Department of Computer Science and Engineering, shanghai jiaotong university, shanghai 200240, china 1. school of Optical-Electrical and Computer Engineering University of Shanghai for Science and Technology Shanghai 200093 China2. Department of Electrical Engineering Shanghai University of Electric Power Shanghai 200090 China3. Department of Computer Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

A three-dimensional representation of vasculature can be extremely important in image-guided neurosurgery, pre-surgical planning. In this paper, a spatial continuity incorporated multi-attribute fuzzy clustering algorithm (MAFCM S) is proposed to segment entire blood vessels from TOF MRA images. This clustering method takes both the intensity information and the geometrical information into account, while most of the cur- rent clustering methods only deal with the former. In this method, a new dissimilarity measure, which integrates the intensity and the geometry shape dissimilarity, is introduced. Because of the presence of the geometrical information, the new measure is able to differentiate the pixels with similar intensity values within different geometrical shape structures. Experimental results show that the new algorithm can get better segmentation.

关键词： fuzzy c-means clustering scale space analysis spatial continuity blood vessel segmentation multi-attribute fuzzy clustering

Naive Bayesian for Email Filtering

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计算机工程 2002年第S1期28卷 101-104页

作者： ZHANG YuntaoGONG LingOUYANG MingguangWANG Yongcheng(school of Electronic & information technology,shanghai jiaotong university,shanghai 200030,china,ytzhang@***) school of Electronic & information technology Shanghai Jiaotong UniversityShanghai 200030China ytzhang mail.sj ***

The paper presents a method of email filter based on Naive Bayesian theory that can effectively filter junk mail and illegal mail. Furthermore, the keys of implementation are discussed in detail. The filtering model is obtained from training set of email. The filtering can be done without the users specification of filtering rules.

关键词： EmailFilteringNaive BayesianMachine learning

Improving TCP Performance over Wireless Links Using Link-Layer Retransmission and Explicit Loss Notification

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Journal of Systems Engineering and electronics 2002年第4期13卷 17-23页

作者： Zhou Zhizhao & Han Zhengzhi College of Electronic and information Engineering, shanghai jiaotong university, shanghai 200030, P. R. china College of Electronic and information Engineering Shanghai Jiaotong University Shanghai 200030 P. R. China

In order to support the mobility of computers during communication, the transport control protocol (TCP) connections between fixed host and mobile host often traverse wired and wireless networks, and the recovery of the losses due to wireless transmission error is much different from congestion control. This paper analyzes the interaction between TCP and link layer retransmission scheme when the correlated packet are losses handled, indicates that a higher value of the maximum number of successive link layer timeout retransmissions has an adverse effect on TCP ability to perform congestion control rapidly. To achieve a better TCP performance, the paper proposes a strategy combining link-layer selective-reject automatic repeat request (ARQ) with explicit loss notification mechanism, which can respond to congestion quickly while keeping wireless link more reliable, and make TCP react to the different packet losses more suitably.

关键词： Congestion control (communication) Mechanisms Performance Transmissions

Anticoagulation property and security of artificial heart valve material

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Science china(Technological Sciences) 2005年第2期48卷 145-162页

作者： WANG Xianghui1, , LIU Xianghuai1,22, 3, ZHANG Feng2, LI Changrong2, YU Liujiang2, ZHENG Zhihong2, WANG Xi2, JIANG Zhenbin4, CHEN Anqing4 & XU Jingfang3 1. Department of Physics, East china Normal university, shanghai 200062, china 2. Ion Beam Lab, shanghai Institute of Mini-system and information, Chinese Academy of Sciences,shanghai 200050, china 3. Department of electronics, school of information Science and technology, East china Normal Univer- sity, shanghai 200062, china 4. shanghai Cardiovascular Institute, Zhongshan Hospital, shanghai 200032, china 1. Department of Physics East China Normal University 200062 Shanghai China 2. Ion Beam Lab Shanghai Institute of Mini-system and information Chinese Academy of Sciences 200050 Shanghai China 3. Department of electronics School of Information Science and Technology East China Normal University 200062 Shanghai China 4. shanghai Cardiovascular Institute Zhongshan Hospital 200032 Shanghai China

Heart valve diseases threaten human health. One reliable way to save lives of such patients is to replace the pathologically changed heart valves by artificial ones. Over 2 million patients have received LTI-carbon heart valve’s implantation. However, the thrombosis after the implantation is one of the difficulties that need to be solved. In order to improve the blood compatibility and security of mechanical heart valves, ion beam technology was used to modify the surface properties of the materials. The investigation results have been summarized in this paper.

关键词： artificial heart valve, ion implantation, plasma immersed ion implantation, ion beam enhanced deposition.

Optimization of HMM Parameters Based on Chaos and Genetic Algorithm for Hand Gesture Recognition

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Journal of Systems Engineering and electronics 2002年第4期13卷 79-84页

作者： Liu Jianghua , Cheng Junshi & Chen Jiapin information Storage and Research Center, shanghai jiaotong university, shanghai 200030, P. R. china information Storage and Research Center Shanghai jiaotong University Shanghai 200030 P. R. China

In order to prevent standard genetic algorithm (SGA) from being premature, chaos is introduced into GA, thus forming chaotic anneal genetic algorithm (CAGA). Chaos ergodicity is used to initialize the population, and chaotic anneal mutation operator is used as the substitute for the mutation operator in SGA. CAGA is a unified framework of the existing chaotic mutation methods. To validate the proposed algorithm, three algorithms, i. e. Baum-Welch, SGA and CAGA, are compared on training hidden Markov model (HMM) to recognize the hand gestures. Experiments on twenty-six alphabetical gestures show the CAGA validity.

关键词： Chaos theory Experiments Genetic algorithms Optimization