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Determination of ocean tide loading displacements in Hong Kong using GPS technique

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science china Earth sciences 2010年第7期53卷 993-1007页

作者： YUAN LinGuo1,3. DING XiaoLi1, SUN HePing2, ZHONG Ping1,3.& CHEN Wu1 1 Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University, Kowloon, Hong Kong, china 2 Key Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, Chinese Academy of sciences, Wuhan 43.077, china 3.Department of Surveying {3., school of Civil {3., southwest jiaotong University, chengdu 61003., china 1. Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic University Kowloon Hong Kong China3. Department of Surveying Engineering School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China2. Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China

Ocean tide loading (OTL) displacements of eight principal constituents at 12 sites in Hong Kong were determined using more than eight years of continuous GPS observations. Parameters of the OTL displacements were estimated using daily GPS solutions obtained with precise point positioning (PPP) technique. The results were compared with predictions from seven latest global ocean tide models. Gravity measurements of OTL in Hong Kong were also used to validate the GPS results. The study shows that the results from both the GPS and gravity measurements agree best with the GOT4.7 and NAO99b models, when the K1 and K2 constituents are excluded. The agreements between the GPS and the model estimates are generally at sub-millimeter level in both the horizontal and vertical directions, except for S2, K2 and K1 constituents that have relatively larger errors. After removing the systematic biases between the GPS and the model estimates, the misfits of M2, S2, N2, O1, P1 and Q1 at all sites are within 0.5 and 1.0 mm in the horizontal and the vertical directions, respectively, whereas K1 and K2 show relatively larger misfits of up to 2.3.mm. Both the GPS and the gravity S2 estimates have large biases with unknown reasons when compared with the modeled values, which needs to be further investigated. The study demonstrates that GPS is capable of estimating the OTL displacements with the same accuracy as the model predictions, especially for coastal areas.

关键词： GPS ocean tide loading ocean tide model site displacement

Continuum and Discrete Element Coupling Approach to Analyzing Seismic Responses of a Slope Covered by Deposits

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Journal of Mountain science 2010年第3期7卷 264-275页

作者： ZHANG Hua LU Yang school of Civil engineering Southwest Jiaotong University Chengdu 610031 P.R. China

Numerical analyses of earthquake effects on the deformation, stability, and load transfer of a slope covered by deposits are traditionally based on the assumption that the slope is a continuum. It would be problematic, however, to extend these approaches to the simulation of the slide, collapse and disintegration of the deposits under seismic loading. Contrary to this, a discrete element method （DEM） provides a means to consider large displacement and rotation of the non-continuum. To take the advantages of both methods of continuum and non- continuum analyses, seismic responses of a slope covered by deposits are studied by coupling a twodimensional （a-D） finite difference method and a 2-D DEM, with the bedrock being modelled by the finite difference grids and the deposits being represented by disks. A smooth transition across the boundaries of the continuous/discontinuous domains is obtained by imposing the compatibility condition and equilibrium condition along their interfaces. In the course of computation, the same time-step value is chosen for both continuous and discontinuous domains. The free-field boundaries are adopted for lateral grids of bedrock domain to eliminate the radiation damping effect. When the static equilibrium under gravity load is obtained, dynamic calculation begins under excitation of the seismic wave input from the continuum model bottom. In this way, responses to the earthquake of a slope covered by deposits are analyzed dynamically. Combined with field monitoring data, deformation and stability of the slope are discussed. The effects of the relevant parameters of spectrum characteristic, duration, andpeak acceleration of seismic waves are further investigated and explained from the simulations.

关键词： Slope deposit continuum discreteelement method dynamic coupling rock/soilinterface

Response of remotely sensed Normalized Difference Water Deviation Index to the 2006 Drought of eastern sichuan Basin

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science china Earth sciences 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1, LU QiFeng2, GAO ZhiQiang3.& PENG Jian4 1 school of Water Resource and Hydropower, sichuan University, chengdu 610065, {3. 2 National Satellite Meteorological Center, {3. Meteorological Administration, Beijing 100081, {3. 3.Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, {3. 4 school of environmental sciences, Peking University, Beijing 100871, {3. 1. school of Water Resource and Hydropower Sichuan University Chengdu 610065 China 2. National Statellite Meteorological Center China Meteorological Administration Beijing 100081 China 3. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 4. school of environmental sciences Peking University Beijing 100871 China

One of the most serious droughts in last century occurred in eastern sichuan Basin in the summer of 2006 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2001―2006 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2006 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale

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 2{3. of Civil engineering,southwest jiaotong University,chengdu 61003.,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

A policy-based automated negotiation for privileges in grid environments

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Journal of Pharmaceutical Analysis 2009年第1期21卷 11-16页

作者： Run-lian Zhang1,2, Xiao-nian Wu2,3. Xiao-she Dong11.school of Electronic & Information engineering, Xi’an jiaotong University, Xi’an 710049, {3. 2.school of Information and Communication, Guilin University of Electronic Technology, Guilin 541004, {3. 3.National Laboratory for Modern Communications, chengdu 610041, {3.. school of Electronic and Information engineering Xi'an Jiaotong University Xi'an 710049 China school of Information anf Communication Guilin University of Electronic Technology Guilin 541004 China National Laboratory of Modern Communications Chengdu 610041 China

To maintain the global consistency of the authorizing is a challenge when the system authorization is changed in grid environments. This paper proposes a policy-based automatically negotiating method to deal with this issue. An effective system framework, which includes the certificate management, the access policy repertory, the negotiator and the automatically negotiating mechanism, is designed and implemented. The experimental results show that automated negotiation can quickly regain the global authorization consistency and only cause a little system overhead increasing. Compared with the manual authorization maintaining, the presented method can reduce the negotiating time significantly, and reduce the meaningless grid jobs because the inconsistent privileges are controlled timely.

关键词： grid security authorization policy negotiation

Co-expression and Immunity of Legionella pneumophila mip Gene and Immunoadjuvant ctxB Gene

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Acta Biochimica et Biophysica Sinica 2005年第3期37卷 199-204页

作者： Tao WANG Jian-Ping CHEN Hong LI Ke-Qian ZHI Lei ZHANG Chun-Lei YANG Da-Chang TAO school of Precliaical and Forensic Medicine of West china,sichuan University,{3.,china school of Stomatolngy,Xi'an jiaotong University,Xi'an 710004,china school of Life science,sichuan University,{3.,china school of Preclinical and Forensic Medicine of West china Sichuan University Chengdu 610041 China Nuclear Physics Institute Academy of Sciences of the Czech Republic Rez Czech Republic

The mip gene of Legionella pneumophila and the ctxB gene of Vibrio cholerae were amplifiedby PCR *** amplified cDNA was ligated to the pcDNA3.1(+)*** recombinant plasmidspcDNA3.1-mip and pcDNA3.1-ctxB were identified by restriction analysis and PCR,and further confirmedby sequencing ***3.3.cells were transfected with pcDNA3.1-mip and pcDNA3.1-ctxB accordingto the Lipofection *** and stable products of the co-expression of the mip gene and ctxB genewere detected by immunofluorescence and Western *** results showed that NIH3.3.cells weresuccessfully transfected,and that the transiently and stably co-expressed products can be detected in thetransfected *** detect the humoral and cellular immune response in immunized mice induced by the co-immunization of the mip and ctxB genes,female BALB/c mice were immunized intramuscularly with pcDNA3.1-mip and *** results showed that the specific antibody titer and the cytotoxic T-lymphocyteresponse for pcDNA3.1-mip immunization and co-immunization were increased compared with that ofpcDNA3.1(+) ***,the specific antibody titer and cytotoxic T-lymphocyte responsefor co-immunization were increased compared with that of pcDNA3.1-mip *** analysisusing one-way analysis of variance(ANOVA)showed that there was a significant difference between thegroups(P<0.01).The results indicated that the ctxB gene enhanced the humoral and cellular immune responseto the mip gene *** findings provide experimental evidence to support the development ofthe *** DNA vaccine.

关键词： Legionella pneumophila co-expression humoral immunity cellular immunity

Growth and Regulation of Non-tax Revenue:Case Study of A Province in Southeastern china

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Growth and Regulation of Non-tax Revenue:Case Study of A Pro...

Advances in numerical methods for the solution of population balance equations for disperse phase systems

2012管理创新、智能科技与经济发展研讨会

作者： Han LIN 1 2,Ying LIU 3.1 school of Economics and Management,southwest jiaotong University,{3.,sichuan,china 2 Research Institute for Fiscal science,Fuzhou,Fujian,china 3.school of Economics and Management,southwest jiaotong University,{3.,sichuan,china

As an important source of government revenue,non-tax revenue occupies a large ***,construction of a scientific,reasonable and standardized system of non-tax revenue and optimization of the structure of government revenue is fundamental to perfect the national income distribution and to set up an effective planning mechanism of public *** paper takes some province in Southeast of china as example,analyzes the characteristics and trends of non-tax revenue of local governments and puts forward some suggestions to regulate the non-tax revenue management.

关键词： Non-tax Revenue Government Revenue Regulation

来源： cnki会议评论

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science china Chemistry 2009年第8期52卷 1063-1079页

作者： SU JunWei1,GU ZhaoLin2,3.& XU X.Yun41 Department of Mechanical engineering and Automation,school of Mechanical engineering,Xi’an {3. University,Xi’an 710049,china 2 Key Laboratory of Mechanics on Disaster and Environment in Western china,Ministry of Education,Lanzhou 73.000,china 3.Department of environmental science and Technology,school of Human Settlements and Civil engineering,Xi’an {3. University,Xi’an 710049,china 4 Department of Chemical engineering,Imperial College London,London SW7 2AZ,UK 1. Department of Mechanical engineering and Automation School of Mechanical Engineering Xi’an Jiaotong University Xi’an 710049 China 2. Key Laboratory of Mechanics on Disaster and Environment in Western china Ministry of Education Lanzhou 730000 China 3. Department of environmental science and Technology School of Human Settlements and Civil Engineering Xi’an Jiaotong University Xi’an 710049 China 4. Department of Chemical engineering Imperial College London London SW7 2AZ UK

Accurate prediction of the evolution of particle size distribution is critical to determining the dynamic flow structure of a disperse phase system.A population balance equation(PBE),a non-linear hyperbolic equation of the number density function,is usually employed to describe the micro-behavior(aggregation,breakage,growth,etc.) of a disperse phase and its effect on particle size *** solution is the only choice in most *** this paper,three different numerical methods(direct discretization methods,Monte Carlo methods,and moment methods) for the solution of a PBE are evaluated with regard to their ease of implementation,computational load and numerical *** attention is paid to the relatively new and superior moment methods including quadrature method of moments(QMOM),direct quadrature method of moments(DQMOM),modified quadrature method of moments(M-QMOM),adaptive direct quadrature method of moments(ADQMOM),fixed pivot quadrature method of moments(FPQMOM),moving particle ensemble method(MPEM) and local fixed pivot quadrature method of moments(LFPQMOM).The prospects of these methods are discussed in the final section,based on their individual merits and current state of development of the field.

关键词： population balance equation direct discretization method Monte Carlo method moment methods disperse phase system

The New Method for CNC Trajectory Machining Motion Planning Based on Reference Time

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武汉理工大学学报 2006年第S2期28卷 659-663页

作者： JIANG Yongmin~1 XU Mingheng~2 1.Department of Mechanical engineering,school of southwest {3. University,chengdu 61003.,china, Department of Mechanical engineering School of Southwest Jiaotong UniversityChengdu 610031China

In order to make motion planning fitting practice,many characteristic of CNC trajectory motion are discussed, such as the geometric function,the motion and the *** is found that the relation between orbit function and motional parame- ter,so the differential equation about the trajectory motion be set-up by the goal of trajectory *** actual motion process is defined as reference time to link planning and *** a new movement planning method based on self-defining *** rest state,the differential simultaneous equation can be calculated according geometric characteristic analysis,it can be get that simple function consisted of coordinate and reference time *** motive state,dynamic parameter can be worked out accord- ing practical value of reference time,It is proved by experiment and simulation that it is a good way to control geometry and motion comprehensively,to reduce computation times and to increase the ability of environmental adaptation for path

关键词： reference time motion planning trajectory simultaneous equation hyperspace