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simulation analysis on Spatial Pattern of Urban Population in Shenyang City,China in Late 20th Century

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Chinese Geographical Science 2011年第1期21卷 110-118页

作者： QIN Zhiqin ZHANG Pingyu Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The spatial distribution of urban population can reflect significantly urban functions and development status. Shenyang, as a typical old industrial city in China, has experienced considerable changes in spatial distribution of population in the process of urban transformation, resulting in the change of urban spatial structure. Based on the sub-district data of Chinese national population censuses in 1982, 1990 and 2000, this study simulates the evolution pattern of spatial distribution of urban population in Shenyang City. Using statistical method and exploratory spatial data analysis (ESDA), we found that the population distribution, on the whole, has presented a balanced and decentralized trend since the 1980s, which characterizes with Chinese suburbanization. Furthermore, based on the investigation of the pattern of population distribution, it is concluded that the negative exponential model fitted the distribution best, and population concentration in the inner suburb kept increasing gradually, meanwhile, the spatial structure of population distribution has presented a polycentric feature since the 1980s. The parameters of the model show that population in the urban core concentrate significantly all the time. The increase of population in the inner suburb influences the population distribution pattern more and more importantly, but the concentration intensity of population cores in inner suburb is still low.

关键词： population distribution urban spatial structure simulation analysis Shenyang City

simulation analysis for O-cell test of pile and the interaction of upper pile and lower pile

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Journal of Harbin Institute of Technology(New Series) 2009年第4期16卷 541-547页

作者：郑英杰张克绪张尔其 School of Civil Engineering Harbin Institute of Technology

In this paper,the soil-pile system of O-cell test of pile is simplified as an axi-symmetric *** using aggregation of quadrilateral isoparametric elements to simulate pile and soil,setting Goodman's elements between pile and soils,a method of numerical simulation analysis on O-cell test of pile is presented with the consideration of nonlinear mechanical behavior of soils and pile-soil *** method is applied to the analysis of a case of O-cell test of *** load-displacement curves and axial force curves of upper pile and lower pile obtained from the O-cell test of pile are fitted,and parameters of the mechanical model of soils and interface are *** results validate that the numerical simulation analysis method put forward in this paper is ***,the interaction and influence of upper pile and lower pile in the O-cell test are also studied with the *** result shows that if load box is located in a soil layer with fine mechanical behavior,the interaction of upper pile and lower pile in O-cell test can be ignored generally.

关键词： O-cell test of pile simulation analysis nonlinear behavior p-s curve interaction

simulation analysis of regional surface mass anomalies inversion based on different types of constraints

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Geodesy and Geodynamics 2021年第4期12卷 298-307页

作者： Bo Zhong Jiangtao Tan Qiong Li Xianpao Li Tao Liu School of Geodesy and Geomatics Wuhan UniversityWuhan430079China Key Laboratory of Geospace Environment and Geodesy Ministry of EducationWuhan UniversityWuhan430079China School of Civil Engineering and Geomatics Southwest Petroleum UniversityChengdu610500China

Surface mass anomalies estimated by mass concentration(mascon)approach using Gravity Recovery and Climate Experiment(GRACE)observations with regularization constraints generally present higher spatial resolution than the spheric harmonic(SH)*** analyze the influence of different types of constraints on the estimation of mascon solutions,we carried out a closed-loop simulation experiment to estimate surface mass anomalies over South America based on simulated GRACE intersatellite geopotential *** regularization with spatial constraint(SC),uniform weighting constraint(UWC),and a prior information constraint(APC)were employed to stabilize the mascon solutions,and the corresponding optimal regularization parameters were determined based on the minimum residual root-mean-square(RMS)*** results show that mascon solutions estimated under different types of constraints are consistent and equivalent when the optimal regularization parameters are *** spatial distributions and main characteristics of regional surface mass anomalies estimated by the three types of constraints agree well,and the values of residual RMS with different constraints are very *** due to the smoothing effect of regularization,the signal strength of mascon solutions is a bit weaker than that of original true signal,especially in the regions with strong *** addition,due to the ill-conditioned problem is more serious for higher grid resolution,the relative contribution of the three types of constraints to the final mascon solutions would be *** results show that the averages of relative contribution percentages of these constraints for 2°×2° mascon grids are 80%-90%,while the corresponding values for 4°×4° mascon grids are 30%-60%.However,based on the minimum residual RMS criterion,the accuracy of estimation results is not affected by the type of constraints and their relative contribution to the final mascon solutions.

关键词： Regional surface mass anomalies Regularization constraints Intersatellite geopotential differences GRACE mascon solutions simulation analysis

simulation analysis and Research of C70GB Fuel Cell Vehicle 1

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simulation analysis of temperature control calculation of RCC gravity dam in the cold region

2016中国汽车工程学会年会暨展览会

作者： Chen Ping Liang Chen Li Jiangqiu Jiang Hongliang State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing Electric Vehicle Co. Ltd.

ISBN: (数字)9789811035272

ISBN: (纸本)9789811035265;9789811098963

Due to long endurance mileage and short fueling time,fuel cell vehicle had became the main development direction of range extend electric *** order to improve the service life and tech- characteristics,many departments carried out research related to the fuel cell and control system of fuel cell *** this study,the power systems,fuel cell systems,power battery systems and other simulation systems were constructed and tested for C70 GB model,and calculate the power,energy consumption and other aspects of the *** simulation results show that the fuel cell can effectively improve the energy power battery vehicle system dynamic and climbing performance,equipped with two 70 MPa cylinders can effectively extend the mileage of the vehicle,and ensure daily using demand.

关键词： new energy vehicle fuel cell power system simulation analysis research

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Journal of Energy and Power Engineering 2009年第9期2卷 11-16页

作者： REN Jin-ke LI Shou-yi YANG Ting-ting LI Yong-gang Xi ＇an University of Technology Xi ＇an 710048 China

In this paper, regarding the actual conditions of a roller compacted concrete dam, three-dimensional finite element relocating mesh method is utilized to simulate and calculate the temperature field of the RCC dam during the construction stage and operating period. The calculation is well consistent with the actual construction process, the thin-layer pouring process the pouring temperature and all kinds of external loads involved being taken into account, By comparing and analyzing of the impact of the cold wave on the dam stress, important references are provided for the RCCD design and the temperature control during construction.

关键词： RCC gravity dam thermal stress: relocating mesh method simulation analysis cold wave

Thermal stress simulation analysis of aerospace optical fibers and connectors and related extensions to high-speed railway area

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High-Speed Railway 2024年第2期2卷 122-132页

作者： Feng Zhou Siyuan Yu Zeren Gao Jie Kan Hao Xu Mengjie Liu The 8th Research Institute of China Electronics Technology Corporation Hefei 230051China Anhui Key Laboratory of Aerospace Optical Fiber Interconnection Technology Hefei 230051China Harbin Institute of Technology Harbin 150001China ANJIANG TEC Wuhu 241000China

Aerospace optical cables and fiber-optic connectors have numerous advantages(e.g.,low loss,wide transmission frequency band,large capacity,light weight,and excellent resistance to electromagnetic interference).They can achieve optical communication interconnections and high-speed bidirectional data transmission between optical terminals and photodetectors in space,ensuring the stability and reliability of data transmission during spacecraft operations in *** have become essential components in high-speed networking and optically interconnected communications for *** stress simulation analysis is important for evaluating the temperature stress concentration phenomenon resulting from temperature fluctuations,temperature gradients,and other factors in aerospace optical cables and connectors under the combined effects of extreme temperatures and vacuum *** this,advanced optical communication technology has been widely used in high-speed railway communication networks to transmit safe,stable and reliable signals,as high-speed railway optical communication in special areas with extreme climates,such as cold and high-temperature regions,requires high-reliability optical cables and ***,based on the finite element method,comprehensive comparisons were made between the thermal distributions of aerospace optical cables and J599III fiber optic connectors under different conditions,providing a theoretical basis for evaluating the performance of aerospace optical cables and connectors in space environments and meanwhile building a technical foundation for potential optical communication applications in the field of high-speed railways.

关键词： Aerospace optical fiber Aerospace optic connector simulation analysis

simulation analysis on the regulation of overflow ecological water consumption in arid areas——A case study in the Canmrik ecological area of the mainstream zone of the Tarim River

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Science China Earth Sciences 2007年第S1期 1-8页

作者： CHEN Xi1, HUANG Yue1, 2, QIAN Jing1, 3, LIU HaiLong1, 2, FENG XianWei1, 2, LIU Ying1, 2, BAO AnMing1 & WANG WeiSheng1 1 Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, ürümqi 830011, China 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China 3 Hong Kong Baptist University, Hong Kong, China

After analyzing the regulation of overflow ecological water consumption in the Canmrik ecological area of mainstream zone of the Tarim River, in this paper a model of ecological bifurcation is developed, the dynamic overflow process of ecological bifurcation is simulated, and the quantitative relationships between the volume of ecological water consumption and the ecological conservation extent and overflow time are analyzed using GIS, advance of freshet and RS means. The results reveal that the effects of discharge and time of ecological bifurcation on the efficiency of ecological water consump-tion are significant, there is a geometrical exponential relationship between the efficiency of ecological bifurcation and the water supply with different discharges and different times under the same eco-logical water consumption, hypsography plays an important role in ecological water consumption, the regulation of ecological water consumption cannot be equated with the ordinary farming irrigation system, a serious water waste will result and the prospective ecological benefits will not be able to be achieved if an ordinary ecological bifurcation is implemented. The efficiency of ecological water con-sumption can be increased by 30% by selecting the bifurcation schemes in an optimized way, which is of the utmost importance for arid areas with shortage of water resources.

关键词： continental river ecological water consumption artificial regulation simulation analysis

simulation analysis and Optimization of Rolling Process of Steel Rim

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World Journal of Mechanics 2021年第3期11卷 34-51页

作者： Wenhua Lv Mao Pang Shunping Li Miaolong Cao School of Mechanical and Energy Engineering Zhejiang University of Science and Technology Hangzhou China Zhejiang Jingu Company Limited Hangzhou China

In order to solve the problems of rolling forming accuracy and fillet thinning of alloy steel rim, a three-dimensional model of three pass rolling process was established, and the influence of different process parameters on forming quality was analyzed by using the finite element software, and the optimal process parameter combination was obtained. On this basis, the simulation results of wheel rim stress and strain for each pass rolling are analyzed, and the particle tracking technology is introduced to analyze the variation rule of stress in each incremental step. Finally, the simulation and experimental results show that the simulation thickness is basically consistent with the actual thickness, which improves the accuracy of rim rolling forming, and further verifies the correctness of rolling process simulation.

关键词： Roll Forming Parameter Optimization simulation analysis Thickness Verification

simulation analysis Module of High-speed Rail Bearings Based on Secondary Development in ADAMS

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Computer Aided Drafting,Design and Manufacturing 2013年第3期23卷 46-50页

作者： ZHANG Li YE Jun XU Juan LUO Yi-chao School of Machinery and Automobile Engineering Hefei University of Technology Hefei 230009 China Luoyang Bearing Science&Technology Co. Ltd Luoyang 471039 China School of Computer and Information Hefei University of Technology Hefei 230009 China

This paper develops a strong secondary development based on ADAMS feature which creates high-speed rail bearings for simulation analysis module. This thesis is in the case of non-circular pattern instructions of how to achieve rapid roller modeling, with analysis of functions and parameters required for the design of the simulation module of the high-speed rail bearing, as well as the design of dialog boxes, the environment and file structure. The specific modules is based on the secondary development language provided by ADAMS ! View. Through the menus, dialog boxes which input parameters, it can achieve high iron bearing automatic modeling, dynamic analysis and post-processing to simplify the analysis of high-speed rail bearing operations, as well as improving the high-speed rail bearing development efficiency.

关键词： ADAMS secondary development high-speed rail bearing simulation analysis