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A SIMPLIFIED NUMERICAL MODEL OF 3.D GROUNDWATER AND SOLUTE TRANSPORT AT LARGE SCALE AREA

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Journal of Hydrodynamics 2010年第3期22卷 319-328页

作者： LIN Lin YANG Jin-Zhong zhang Bin ZHU Yan State Key Laboratory of Water Resources and Hydropower engineering Wuhan University Wuhan 430072China institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China

A simplified numerical model of groundwater and solute transport is developed. At large scale area there exists a big spatial scale difference between horizontal and vertical length scales. In the resultant model, the seepage region is particularly divided into several virtual layers along the z direction and vertical 1.D columns covering x-y 2-D area according to stratum properties. The numerical algorithm is replacing the full 3.D water and mass balance analysis as the 2-D Galerkin finite element method in x- and y-directions and 1.D finite differential approach in the z direction. The reasonable method of giving minimum thickness is successfully used to handle transient change of water table, drying cells and problem of rewetting. The solution of the simplified model is preconditioned conjugate gradient and ORTHOMIN method. The validity of the developed 3.D groundwater model is tested with the typical pumping and backwater scenarios. Results of water balance of the computed example reveal the model computation reliability. Based on a representative 3.D pollution case, the solute transport module is tested against computing results using the MT3.MS. The capability and high efficiency to predict non-stationary situations of free groundwater surface and solute plume in regional scale problem is quantitatively investigated. It is shown that the proposed model is computationally effective.

关键词： groundwater movement solute transport simplified model 3.D mass balance numerical simulation

3. thermo-hydro-mechanical-migratory coupling model and FEM analyses for dual-porosity medium

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Science china(Technological Sciences) 2010年第8期53卷 2172-2182页

作者： zhang YuJun 1.zhang WeiQing 2 1.State Key Laboratory of Geomechanics and Geotechnical engineering,institute of Rock and Soil Mechanics, Chinese Academy of Sciences,wuhan 43.071.china 2School of Civil engineering,Southwest Jiaotong university,Chengdu 61.03.1}china 1. State Key Laboratory of Geomechanics and Geotechnical engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China2. School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China

One kind of 3. coupled thermo-hydro-mechanical-migratory model for saturated-unsaturated dual-porosity medium was established,in which the stress field and the temperature field are single,but the seepage field and the concentration field are double,and the influences of sets,spaces,angles,continuity ratios,stiffness of fractures on the constitutive relationship of the medium can be *** relative three-dimensional program of finite element method was also *** comparing with the existing computation example,reliability of the model and the program were *** a hypothetical nuclear waste repository as a calculation example,the radioactive nuclide leak was simulated numerically with both the rock mass and the buffer being unsaturated media,and the temperatures,negative pore pressures,flow velocities,nuclide concentrations and normal stresses in the rock mass were *** results showed that the temperatures,negative pore pressures and nuclide concentrations in the buffer all present nonlinear changes and distributions that even though the saturation degree in porosity is only about 1.9 of that in fracture,the flow velocity of underground water in fracture is about 6 times of that in porosity because the permeability coefficient of fracture is almost four orders higher than that of porosity,and that the regions of stress concentration occur at the vicinity of two sides of the boundary between buffer and disposal pit wall.

关键词： dual-porosity medium thermo-hydro-mechanical-migratory coupling three-dimensional model FEM analysis

Tele-Network Design Based on Queue Competition Algorithm

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wuhan {1. Journal of Natural Sciences 2003年第S1期8卷 327-330页

作者： Huang zhang-can, Wan Li-jun, Tang Tao, Chen Zheng-xuState Key Laboratory of Software {1., wuhan {3., wuhan 43.072, Hubei, chinaSchool of Material Science and {1., wuhan {3. of Technology , wuhan 43.070, Hubei, chinaSchool of Automation, wuhan {3. of Technology, wuhan 43.070, Hubei, chinaSchool of Science, wuhan {3. of Technology, wuhan 43.070, Hubei, china wuhan {1. State Key Laboratory of Software Engineering Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan {1. of Technology School of Material Science and Engineering Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) wuhan {1. of Technology School of Automation Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) wuhan {1. of Technology School of Science Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***)

In this paper, we report research on how to design the tele-network. First of all, we defined the reliability of tele-network. According to the definition, we divide the whole reliability into two parts:the reliability of the mini-way and that of the whole system. Then we do algebra unintersection of the mini-way, deriving a function of reliability of tele-network. Also, we got a function of the cost of tele-network after analyzing the cost of arcs and points. Finally, we give a mathematical model to design a tele-network. For the algorithm, we define the distance of a network and adjacent area within certain boundaries . We present a new algorithm--Queue Competition Algorithm (QCA) based on the adjacent area . The QCA correlates sequence of fitnesses in their father-generations with hunting zone of mutation and the number of individuals generated by mutation, making the stronger fitness in a small zone converge at a local extreme value, but the weaker one takes the advantage of lots of individuals and a big zone to hunt a new local extreme value. In this way, we get the overall extreme value. Numerical simulation shows that we can get the efficient hunting and exact solution by using QCA. The QCA efficient hunting and exact solution.

关键词： reliability Queue Competition algorithm the distance of a network adjacent area

Research and Development of an Embedded Numerical Control System

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武汉理工大学学报 2006年第S3期28卷 1121-1124页

作者： zhang Jinhuan School of Information {1.,wuhan {3. of Technology,wuhan 43.070,china, School of Information engineering Wuhan University of TechnologyWuhan 430070China

This paper puts forward a new scheme of Embedded Numerical Control System based on ARM and DSP,which is at the base of research on traditional numerical control system and embedded *** the paper also describes the develop- ment of hardware and software *** the development and realization are based on the idea of module *** embed- ded numerical control system,using ARM and DSP to construct the main control platform,realizes the real-time operation of sys- tem and improves the stability and reliability with the modular designing ideas of hardware and software and with the support of embedded real-time operating system(uc/os-Ⅱ).And the system could realize the multi-network supporting,which is also accord with the development of modularization,flexibility and latticing of numerical control system.

关键词： real-time operating system embedded technology numerical control system ARM DSP

The optimization of DNA encodings based on GA/SA algorithms

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Progress in Natural Science:Materials International 2007年第6期17卷 739-744页

作者： Wang Wei1. Zheng Xuedong2, zhang Qiang1.and Xu Jin2(1. Liaoning Key Laboratory of Intelligent Information Processing, Dalian {1., Dalian 1.6622, china 2. Department of Control Science and engineering, Huazhong {1. of Science and Technology, wuhan 43.074, china) [a]Liaoning Key Laboratory of Intelligent Information Processing Dalian University Dalian China [b]Department of Control Science and engineering Huazhong Univerisity of Science and Technology Wuhn China

The design of DNA sequence plays an important role in improving the reliability of DNA computation. Proper constrained terms that DNA sequence should satisfy are selected, and then the evaluation formulas of each DNA individual corresponding to the selected constrained terms are proposed. The heuristic improved genetic algorithm (GA)/simulated annealing (SA) algorithm is presented to solve the multi-objective optimize problem, and the DNA sequence design system is developed. Furthermore, an example is illustrated to show the efficiency of our method given here.

关键词： DNA encoding multi-objective optimize GA/SA algorithms

Numerical simulation of ski-jump jet motion using lattice Boltzmann method

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Science china(Technological Sciences) 2011年第S1期54卷 72-75页

作者： zhang Hua 1.&zhang XiaoDong 2 1.School of Renewable Energy,North china Electric Power university,Beijing 1.2206,china 2 School of Energy Power and Mechanical engineering,North china Electric Power university,Beijing 1.2206,china 1. School of Renewable Energy North China Electric Power University Beijing 102206 China 2. School of Energy Power and Mechanical engineering North China Electric Power University Beijing 102206 China

Based on the lattice Boltzmann method,a lattice Boltzmann(LB) model of the ski-jump jet two-phase flow is developed first and the corresponding boundary conditions are studied.A simple case study of a droplet horizontal movement calculation is carried out to test and verify the model,where level set method is used to track and reconstruct the moving droplet free surface. Then,we numerically simulate a two dimensional flow field of the ski-jump jet with the LB model,derive the moving surface and velocity vector field of the jet *** simulation results are very consistent with the physical *** effectiveness and reliability of the model are demonstrated by the numerical examples.

关键词： ski-jump jet droplet lattice Boltzmann method interface numerical simulation

Pair-wise error probability and its Chernoff upper bound for unitary space-time code

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Science china(Information Sciences) 2010年第8期53卷 1613-1621页

作者： zhang DaPeng 1.2 , LIU Ju 1., XU HongJi 1.& JI Hui 1.1.School of Information Science and {1., Shandong university, Jinan 2501.0, china 2 State Key Laboratory of Integrated Services Networks, Xidian university, Xi’an 71.071. china 1. School of Information Science and engineering Shandong University Jinan 250100 China2. State Key Laboratory of Integrated Services Networks Xidian University Xi’an 710071 China

Unitary space-time code is ideally suited for rapid fading scenarios as it can operate well without channel state information (CSI), which is of vital significance for improving the effectivity and reliability of wireless communication systems. Pair-wise error probability (PEP) is an important factor for studying the reliability of a communication system. However, the existing scheme only gives the final result of PEP and the corresponding Chernoff upper bound (CUB) is obtained through magnification, which is not of universal significance for this kind of problems. In this paper, we employ the log-likelihood ratio of probability density functions of the received signals conditioned on the two possibly transmitted signals and by virtue of moment generating function we give the details in deriving the final precise residue expression for PEP and its CUB. At last, we verify the above results by simulations.

关键词： multiple-input multiple-output space-time code unitary space-time code pair-wise error probability Chernoff upper bound

A study on compressive shock wave propagation in metallic foams

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Science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 279-287页

作者： WANG ZhiHua1.2,zhang YiFen2,REN HuiLan1.& ZHAO LongMao2 1.State Key Laboratory of Explosion Science and Technology,Beijing {1. of Technology,Beijing 1.0081.china 2 {1. of Applied Mechanics and Biomedical engineering,Taiyuan university of Technology,Taiyuan 03.024,china 1. State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China2. Institute of Applied Mechanics and Biomedical Engineering Taiyuan University of Technology Taiyuan 030024 China

Metallic foam can dissipate a large amount of energy due to its relatively long stress plateau,which makes it widely applicable in the design of structural crashworthiness. However,in some experimental studies,stress enhancement has been observed when the specimens are subjected to intense impact loads,leading to severe damage to the objects being protected. This paper studies this phenomenon on a 2D mass-spring-bar model. With the model,a constitutive relationship of metal foam and corresponding loading and unloading criteria are presented; a nonlinear kinematics equilibrium equation is derived,where an explicit integra-tion algorithm is used to calculate the characteristic of the compressive shock wave propagation within the metallic foam; the effect of heterogeneous distribution of foam microstructures on the shock wave features is also included. The results reveal that under low impact pulses,considerable energy is dissipated during the progressive collapse of foam cells,which then reduces the crush of objects. When the pulse is sufficiently high,on the other hand,stress enhancement may take place,especially in the heterogeneous foams,where high peak stresses usually occur. The characteristics of compressive shock wave propagation in the foam and the magnitude and location of the peak stress produced are strongly dependent on the mechanical properties of the foam material,amplitude and period of the pulse,as well as the homogeneity of the microstructures. This research provides valuable insight into the reliability of the metallic foams used as a protective structure.

关键词： aluminum foam heterogeneous intensive pulse loading stress enhancement

A new neural-network-based method for structural damage identification in single-layer reticulated shells

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Frontiers of Structural and Civil engineering 2024年第1期18卷 104-121页

作者： Jindong zhang Xiaonong GUO Shaohan ZONG Yujian zhang College of Civil engineering Tongji UniversityShanghai 200092China china Construction Eighth {1. Division Co. Ltd.Shanghai 200135China

Single-layer reticulated shells(SLRSs)find widespread application in the roofs of crucial public structures,such as gymnasiums and exhibition *** this paper,a new neural-network-based method for structural damage identification in SLRSs is ***,a damage vector index,NDL,that is related only to the damage localization,is proposed for SLRSs,and a damage data set is constructed from NDL *** the basis of visualization of the NDL damage data set,the structural damaged region locations are identified using convolutional neural networks(CNNs).By cross-dividing the damaged region locations and using parallel CNNs for each regional location,the damaged region locations can be quickly and efficiently identified and the undamaged region locations can be ***,a damage vector index,DS,that is related to the damage location and damage degree,is proposed for *** on the damaged region identified previously,a fully connected neural network(FCNN)is constructed to identify the location and damage degree of *** effectiveness and reliability of the proposed method are verified by considering a numerical case of a spherical *** calculation results showed that the proposed method can quickly eliminate candidate locations of potential damaged region locations and precisely determine the location and damage degree of members.

关键词： single-layer reticulated shell damage identification neural network convolutional neural network cross-partitioning method