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STUDY OF HYDRODYNAMIC FORCES OF SHIPS IN NARROW WATERWAY

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Journal of Hydrodynamics 2003年第4期15卷 113-117页

作者： Zhang Xie-dong, Wu Xiu-heng School of transportation, wuhan university of technology,{2., china Sch. of Transp. Wuhan Univ. of Technol. Wuhan 430063 China

The collision of ships in narrow waterway may occur for a variety of *** hydrodynamic forces between two ships change the maneuvering characteristics of ships *** based on the boundary element method, this paper proposes a calculation method for hydrodynamicinteraction forces between ships under meeting and passing conditions in narrow waterway. Theresults from this method are compared with the existing results obtained from other theoreticalapproaches, and they are in good agreement.

关键词： collision of ships narrow waterway hydro-dynamic interaction boundaryelement method

NUMERICAL INVESTIGATIONS INTO THE FRICTION REDUCTION BY MICROBUBBLES FOR FLAT PLATES

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Journal of Hydrodynamics 2003年第3期15卷 82-88页

作者： Zhan De-xin, Wang Jia-mei, Lin Li-ming School of transportation, wuhan university of technology,{2., china, Sch. of Transp. Wuhan Univ. of Technol. Wuhan 430063 China

The two-dimensional flow on the flat plate with injected microbubbles issimulated using the software, PHOENICS (V3. 2., usually used in the CFD (Computational FluidDynamics). A set of formulas for K-ε turbulence model modified with the presence of microbubbles,is employed. With considering the effect of gravity, interfacial lift, inter-phase friction, virtualmass force and interfacial pressure on the flow with microbubbles, numerical calculations for theinfluence of variable air volume fracton as well as distribution, injecting speed, microbubblediameter and position of introducing microbubbles on the friction reduction are presented. Resultsshow that the friction reduction increases with increasing volume fraction and microbubble diameterwithin the range of 100μm, and that the velocity in the boundary layer with microbubbles is greaterthan that without microbubbles. The order of magnitude and trends of the experimental skin-frictionare reproduced well. The uniform free-stream speed in all cases is 4m/s, giving Reynolds number ofup to 2. million.

关键词： flat plate friction reduction by microbubbles modified K-ε turbulencemodel numerical simulation

A Structured Methodology for Local Network Design Engineering

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Journal of Systems Engineering and Electronics 1992年第1期3卷 64-72页

作者： Li Layuanwuhan university of Water {2. Engineering, wuhan 430063, china wuhan university of Water {2. Engineering Wuhan 430063 China

This paper presents a structured methodology for local network design engineering (SMLNDE). A complex and fuzzy project for local network design can be decomposed into a set of simple and particular activities using the SMLNDE. The SMLNDE allows rigorous requirements definition and permits the exhaustive consideration of the large number of factors influencing local network design engineering. The complete and clear design documentations and an optimal design can also be provided by the methodology. The SMLNDE has been implemented using the structured analysis and design technique. The study shows that the SMLNDE is an effective design methodology for the large and complex local networks.

关键词： Local network Design engineering Structured methodology.

Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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wuhan university Journal of Natural Sciences 2002年第1期7卷 107-112页

作者： Zheng Hua 1 , Du Yu-min 2.1. Department of Chemical Engineering, wuhan university of technology, wuhan 430070, Hubei,{2. 2. college of Chemistry and Molecular Sciences, wuhan university, wuhan 430072. Hubei,{2. Department of Chemical Engineering Wuhan University of Technology Wuhan Hubei China college of Chemistry and Molecular Sciences Wuhan University Wuhan Hubei China

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2.(weight) chitosan acetic acid solution with 1.5%(weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 30°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 30%(weight). The CS/ CMKGM blend films provided promising biomedical applications.

关键词： Key words chitosan carboxymethylated konjac glucomannan blend films structure characterization

The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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Science china(Technological Sciences) 2006年第2期49卷 238-247页

作者： ZHANG Hai’ou1, QIAN Yingping1,3, WANG Guilan1 & ZHENG Qiguang2.1. School of Material Science and technology, Huazhong university of Science and technology, wuhan 430074, china 2. Institute of Laser technology and Engineering, Huazhong university of Science and technology, wuhan 430074, china 3. Mechanical Engineering college, Hubei university of technology, wuhan 430068, china School of Material Science and technology Huazhong University of Science and Technology Wuhan China Mechanical Engineering college Hubei University of Technology Wuhan China Institute of Laser technology and Engineering Huazhong University of Science and Technology Wuhan China

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

A Routing Algorithm for Distributed Optimal Double Loop Computer Networks

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Journal of Systems Engineering and Electronics 1994年第1期5卷 37-43页

作者： Li Layuan(Department of Electrical Engineering and Computer Science.wuhan university of Water {2., wuhan 430063, P. R. china) Department of Electrical Engineering and Computer Science Wuhan University of Water Transportation Wuhan 430063 P.R. China

A routing algorithm for distributed optimal double loop computer networks is proposed and analyzed. In this paper, the routing algorithm rule is described, and the procedures realizing the algorithm are given. The proposed algorithm is shown to be optimal and robust for optimal double loop. In the absence of failures,the algorithm can send a packet along the shortest path to destination; when there are failures,the packet can bypasss failed nodes and links.

关键词： Computer networks Double loop Routing algorithm

A　Hybrid　Formal　Description　Method　Based　on　FSM,CSP　and　ADT　for　Communication　Protocol

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Journal of Systems Engineering and Electronics 1998年第3期9卷 29-38页

作者： Li Layman(wuhan transportation {2.l 430063, P. R. china) wuhan transportation {2. 430063 P. R. China

Since communication protocol deals with complex issues related to distribution such as communication, concurrency and synchronization, their development needs to be traced by using sophisticated formal description methods. This paper presents a new hybrid formal method for communication protocol specification. In this method, finite state machine (FSM), communication sequential process (CSP) and abstract data type (ADT) are mixed and the best features of these approaches are offered. In this paper, the main formal description techniques (FDT) for protocol engineering are brieny introduced and a hybrid formal description method based on the FSM, CSP and ADT for communication protocol is described. Finally, this paper presents the formal specification of an example protocol for LAN by using the proposed hybrid formal method. The results of studies show that the hybrid formal description method for communication protocol is an available and effective approach.

关键词： Communication protocol Formal description techniques,Protocol engineering Hybrid formal method

LATTICE BGK MODEL FOR THE INCOMPRESSIBLE NAVIER-STOKES EQUATION

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Journal of Hydrodynamics 2003年第3期15卷 96-102页

作者： Zhang Xiao-jun, Liu Zu-yuan School of transportation, wuhan university of technology,{2., china, School of transportation Wuhan University of Technology Wuhan 430063 China

In this paper a Lattice Bhatager-Gross-Krook (LBGK) model to simulateincompressible flow is developed. The basic idea is to explicitly eliminate the compressible effect,due to the density fluctuation in the existing LBGK models. In the proposed incompressible LBGKmodel, the pressure p instead of the constant mass density ρ_0 is the independent dynamic *** incompressible Navier-Stokes equations are exactly derived from this incompressible LBGK *** order to test the LBGK model, the plane Poiseuille flow driven either by pressure gradient or afixed velocity profile at entrance as well as the 2.D Womersley flow are simulated. The numericalresults are found to be in excellent agreement with theory and the results of previous studies.

关键词： lattice BGK method incompressible navier-stokes equation poiseuilleflow wornersley flow

Architecture and application of integrated spatial information service platform for digital mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 706-711页

作者： ZHANG Jin1, XIAO Jie2.1. college of Mining, Taiyuan university of {2., Taiyuan 03002., china 2. Institute of Geodesy and Geophysics, Chinese Academy of Sciences, wuhan 430077, china college of Mining Taiyuan University of Technology Taiyuan 030024 China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China

Using enterprise GIS platform, spatial databases and modern information technology, building geo-spatial information service platform of digital mine which has the features of the data exchange service, enterprise GIS services, directory services, logging services, is key technology and application infrastructure for digital mine. Based on the support of geospatial information service platform of digital mine, the professional GIS application service adapter can be developed and the application supports related to mining application system can be realized. Using high-resolution satellite remote sensing data, the mine functional partition map and geographic grids can be divided, and the geographic grid parts, status and events of important features of the surface object were investigated and defined. The system architecture and technical characteristics of integrated spatial information service platform were analyzed firstly, which guarantee service ability of digital mine. The methods and applications of functional partition map for integrated management service platform were discussed which are the services scheme of digital mine. The application results indicated that digital mine upgrades and enhances the capability and range of mine surveying and mapping, and is of great significance for guarantee of efficient, green and intensive exploitation of mine.

关键词： platform architecture web services application services digital mine