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A Network-Based VPN Architecture Using Virtual Routing

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wuhan University Journal of Natural Sciences 2005年第1期10卷 161-164页

作者： ZHANG Bao-liang 1,2.HU Han-ping 1,2.,WU Xiao-gang 1,2. KONG Tao 31.State Education Ministry Key Laboratory of Image Information and Intelligent Control, wuhan 430074, hubei,{2. 2.institute of Pattem Recognition and Artificial Intelligonce, Huazhong University of Science and Technology, wuhan 430074, hubei,{2. 3.709th research institute of{2. Shipbuilding engineering Society, wuhan 430074, hubei,{2. Lab. of Image Info. Wuhan 430074 China Inst. of Pattern Recognition Huazhong Univ. of Sci. and Technol. Wuhan 430074 China 709th Res. Inst. China Shipbuilding Eng. Society Wuhan 430074 China

A network-based Virtual Private Network (VPN) architecture by using fundamental routing mechanism is proposed. This network is a virtual overlay network based on the relay of IP-in-IP tunneling of virtual routing modules. The packet format employs the encapsulation of IPSec ESP(Encapsulating Security Payload), an impact path code and an extended DS(Differentiated Services) code to support multi-path routing and QoS. Comparing with other models of VPN, this network system can be deployed in the current network with little investment, and it is easy to implement. The simulation result shows its performance is better than the traditional VPN system of black box mode.

关键词： virtual routing network-based VPN proactive defense

Seabed Classification Using BP Neural Network Based on GA

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Acta Oceanologica Sinica 2003年第4期22卷 523-531页

作者： Yang Fanlin1, Liu Jingnan2.1. GPS engineering research Center, {2. University, {2. 430079, china. 2. Presidential Secretariat, {2. University, {2. 430079, china GPS engineering research Center Wuhan University Wuhan 430079 China Presidential Secretariat Wuhan University Wuhan 430079 China

Side scan sonar imaging is one of the advanced methods for seabed study. In order to be utilized in other projects, such as ocean engineering, the image needs to be classified according to the distributions of different classes of seabed materials. In this paper, seabed image is classified according to BP neural network, and. Genetic Algorithm is adopted in train network in this paper. The feature vectors are average intensity, six statistics of texture and two dimensions of fractal. It considers not only the spatial correlation between different pixels, but also the terrain coarseness. The texture is denoted by the statistics of the co-occurrence matrix. Double Blanket algorithm is used to calculate dimension. Because a uniform fractal may not be sufficient to describe a seafloor, two dimensions are calculated respectively by the upper blanket and the lower blanket. However, in sonar image, fractal has directivity, i. e. there are different dimensions in different direction. Dimensions are different in acrosstrack and alongtrack, so the average of four directions is used to solve this problem. Finally, the real data verify the algorithm. In this paper, one hidden layer including six nodes is adopted. The BP network is rapidly and accurately convergent through GA. Correct classification rate is 92.5 % in the result.

关键词： BP network co-occurrence matrix fractal classification genetic algorithin

Remolding Diversified Objects in Ada95: Toward A Object Pattern

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wuhan University Journal of Natural Sciences 2001年第Z1期6卷 247-255页

作者： Liang Xian zhong, Wang Zhen yu wuhan digital {2. institute P. O. Box 742.3, wuhan 430074, china wuhan digital {2. institute Wuhan China

Ada provides full capacities of supporting object orientation, but the diversified objects patterned in Ada are so intricate that Ada95's aim would be demolished. In order to complement the disfigurement that Ada does lack for a pristine notion of class, this paper presents a remolded object pattern known as A object, an Ada based class description language A ObjAda aiming at support for A object pattern and the related approach for key algorithms and implementation. In consequent, A ObjAda hereby promotes Ada with highlighted object orientation, which not only effectively exploits the capacities in Ada95, but also rationally hides befuddling concepts from Ada95.

关键词： ADT (abstract data type) ASM (abstract state machine) V object U object A object pattern

Event-based Implicit Invocation Decentralized in Ada

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wuhan University Journal of Natural Sciences 2001年第Z1期6卷 239-246页

作者： Liang Xian zhong, Wang Zhen yu wuhan digital {2. institute, P. O. Box 742.3, wuhan 430074, china wuhan digital {2. institute Wuhan China

Nowadays more and more attraction is drawn by the event based implicit invocation one of useful architectural patterns, because of its loose coupling between components in the architecture and reactive integration in software systems. Analyzing object oriented interaction with objects, this paper, based upon the principle of software architecture, presents an approach on event based object model with Ada exception handler. Consequently it is possible for us to improve, with adding specific architectural patterns, traditional programming languages into architectural description languages.

关键词： implicit invocation architectural pattern EBO (event based object) exception handler

HCWCI/Carbon Steel Bimetal Liner by Liquid-Liquid Compound Lost Foam Casting

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Journal of Iron and Steel research International 2012年第10期19卷 13-19页

作者： XIAO Xiao-feng1,2. YE Sheng-ping2. YIN Wei-xin3, XUE Qiong4 (1. School of Mechanical engineering and Automation, wuhan Textile University, wuhan 430073, hubei, china 2. State Key Laboratory of Material Processing and Die and Mould Technology, Huazhong University of Science and Technology, wuhan 430074, hubei, china 3. wuhan Zhike Abrasive-Resistant Material Science and Technology Development Co Ltd, wuhan 430073, hubei, china 4. College of Science, wuhan University of Technology, wuhan 430079, hubei, china) School of Mechanical engineering and Automation Wuhan Textile University Wuhan Hubei China State Key Laboratory of Material Processing and Die and Mould Technology Huazhong University of Science and Technology Wuhan Hubei China wuhan Zhike Abrasive-Resistant Material Science and Technology Development Co Ltd Wuhan Hubei China College of Science Wuhan University of Technology Wuhan Hubei China

Impact, friction and corrosion from the grinding balls and the grinding medium during the mineral processing result in liner breakage. Liner, made from Hadfield steel or alloyed steel, could not have served in wet grinding environment for more than ten months. Composite liner, made from HCWCI (high Cr white cast iron) and carbon steel, has been developed successfully with liquid-liquid composing process based on LFC (lost foam casting). The microstructure of composite was analyzed with optical microscope, SEM (scanning electron microscope)/EDX energy-dispersive X-ray and XRD (X-ray diffraction). According to micrograph, the combination region of two metals was staggered like dogtooth, no mixtures occurred between two liquid metals, and its interface presented excellent metallurgical bonding state. The results of mechanical property test show that, the hardness of HRC, the fracture toughness, and the bending strength are more than 61, 16.5 J/cm2.and 1 600 MPa, respectively. Comparison between liners made from bimetal composite and alloyed steel has also been investigated in industrial hematite ball mill. The results of eight months test in wet grinding environment prove that the service life of bimetal composite liner is three times as long as that of one made from alloyed steel.

关键词： composite liner bimetal liquid-liquid compound composite interface lost foam casting high Cr white cast iron

Gradient analysis of landscape spatial and temporal pattern changes in Beijing metropolitan area

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Science china(Technological Sciences) 2010年第S1期53卷 91-98页

作者： YANG YeTao1,ZHOU QiMing2.GONG JianYa3 & WANG YingYing4 1 institute of Geophysics and Geomatics,china University of Geosciences,{2. 430074,china 2.Department of Geography,Hong Kong Baptist University,Hong Kong 3 State Key Laboratory of Information engineering in Surveying,Mapping and Remote Sensing,{2. University,{2. 430074,china 4 hubei Provincial Bureau of Meteorology,{2. 430074,china institute of Geophysics and Geomatics China University of Geosciences Wuhan China Department of Geography Hong Kong Baptist University Hong Kong China State Key Laboratory of Information engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan China hubei Provincial Bureau of Meteorology Wuhan China

The gradient based landscape metrics analysis is now widely used to study the landscape pattern changes in respond to the *** order to discover the trend of spatio-temporal changes in Beijing metropolitan area during the past 15 years,several landscape metrics are computed using a moving window along a 96 km long transect across Beijing metropolitan area from west to ***,the spatial extent of sub-landscape,which is determined by the moving window’s size,is profoundly *** results show that the metrics varies smoothly and regularly along the selected transect when the window size is greater than 6 km×6 km,and irregularly fluctuated for the smaller window size,that the spatial and temporal landscape characteristics of Beijing city match the hypothetical framework of spatio-temporal urban sprawl in the form of alternating processes of diffusion and coalescence well,and that some new trends of the urban sprawl style in Beijing metropolitan area,such as leap-frog manner,are also detected by the gradient landscape analysis.

关键词： gradient analysis landscape metrics spatio-temporal urban expansion multi-extent

Robust H-infinity fuzzy control for uncertain Markovian jump nonlinear singular systems with wiener process

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控制理论与应用（英文版） 2010年第2期8卷 205-210页

作者： Aiqing ZHANG 1 , Huajing FANG 2.(1.College of Mathematics and Computer Science, Jianghan University, wuhan hubei 430056,{2. 2.Department of Control Science and engineering, Huazhong University of Science and Technology, wuhan hubei 430074,{2.) College of Mathematics and Computer Science Jianghan University Wuhan Hubei China Department of Control Science and engineering Huazhong University of Science and Technology Wuhan Hubei China

This paper deals with the problems of robust stochastic stabilization and H-infinity control for Markovian jump nonlinear singular systems with Wiener process via a fuzzy-control approach. The Takagi-Sugeno (T-S) fuzzy model is employed to represent a nonlinear singular system. The purpose of the robust stochastic stabilization problem is to design a state feedback fuzzy controller such that the closed-loop fuzzy system is robustly stochastically stable for all admissible uncertainties. In the robust H-infinity control problem, in addition to the stochastic stability requirement, a prescribed performance is required to be achieved. Linear matrix inequality (LMI) sufficient conditions are developed to solve these problems, respectively. The expressions of desired state feedback fuzzy controllers are given. Finally, a numerical simulation is given to illustrate the effectiveness of the proposed method.

关键词： Fuzzy control H-infinity control Singular systems Stochastic stability Linear matrix inequality (LMI)

Second-order consensus in networks of dynamic agents with communication time-delays

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Journal of Systems engineering and Electronics 2010年第1期21卷 88-94页

作者： Bo Yang1,2. Huajing Fang3, and Hua Wang4 1. School of Navigation, wuhan University of Technology, wuhan 430063, P. R.{2. 2. wuhan Second Ship Design and research institute, wuhan 430064, P. R.{2. 3. Department of Control Science and engineering, Huazhong University of Science and Technology, wuhan 430074, P. R.{2. 4. Department of Aerospace and Mechanical engineering, Boston University, Boston MA02.15, USA School of Navigation Wuhan University of Technology Wuhan 430063 P. R. China wuhan Second Ship Design and research {2. Wuhan 430064 P. R. China Department of Control Science and engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China Department of Aerospace and Mechanical engineering Boston University Boston MA02215 USA

This paper proposes second-order consensus protocols with time-delays and gives the measure of the robustness of the protocols to the time-delay existing in the network of agents with second-order dynamics. By employing a frequency domain method, it is proven that the information states and their time derivatives of all the agents in the network achieve consensus asymptotically, respectively, for appropriate communication timedelay if the topology of weighted network is connected. Particularly, a tight upper bound on the communication time-delay that can be tolerated in the dynamic network is found. The consensus protocols are distributed in the sense that each agent only needs information from its neighboring agents, which reduces the complexity of connections between neighboring agents significantly. Numerical simulation results are provided to demonstrate the effectiveness and the sharpness of the theoretical results for second-order consensus in networks in the presence of communication time-delays.

关键词： second-order consensus protocols dynamic networks algebraic graph theory frequency domain analysis com-munication constraints.

Prediction of Tumor Outcome Based on Gene Expression Data

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wuhan University Journal of Natural Sciences 2004年第2期9卷 177-182页

作者： Liu Juan 1,2. Hitoshi Iba 3 1. School of Computer, wuhan University, wuhan 430072.{2., china 2. State Key Laboratory of Software engineering, wuhan 430072.{2., china 3. Department of Frontier Informatics, University of Tokyo, Tokyo 113-8656, Japan School of Computer Wuhan University Wuhan Hubei China State Key Laboratory of Software engineering Wuhan Hubei China Department of Frontier Informatics University of Tokyo Tokyo Japan

Gene expression microarray data can be used to classify tumor types. We proposed a new procedure to classify human tumor samples based on microarray gene expressions by using a hybrid supervised learning method called MOEA+WV (Multi-Objective Evolutionary Algorithm+Weighted Voting). MOEA is used to search for a relatively few subsets of informative genes from the high-dimensional gene space, and WV is used as a classification tool. This new method has been applied to predicate the subtypes of lymphoma and outcomes of medulloblastoma. The results are relatively accurate and meaningful compared to those from other methods. Key words bioinformatics - tumor classification - Pareto optimization - MOEA CLC number Q 786 - TP 181 Foundation item: Supported by the National Natural Science Foundation of china (60301009), the Foundation of Young Scholars of Ministry of Education of china (150118) and Chenguang Project of {2. City (2.112.009).Biography: Liu Juan (1970-), female, Associate Professor, Postdoctoral, research direction: bioinformatics, data mining, machine learning.

关键词： bioinformatics tumor classification Pareto optimization MOEA