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Analysis of Porter’s Five Forces Competitive Model in China’s Property Rights Trading Market
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作者 Weinong Wang 《Proceedings of Business and Economic Studies》 2024年第3期206-211,共6页
In recent years,China’s property rights trading market has been extremely competitive,but there are also new contradictions and challenges.This paper aims to analyze the external and internal competitive market of th... In recent years,China’s property rights trading market has been extremely competitive,but there are also new contradictions and challenges.This paper aims to analyze the external and internal competitive market of the property rights market through Porter’s five forces competition model,then find out the problems and defects in the development,thereby promoting the better development and progress of China’s property rights trading market. 展开更多
关键词 Porter’s five forces competitive model Market optimization Innovative development
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Comparisons of Wave Force Model Effects on the Structural Responses and Fatigue Loads of a Semi-Submersible Floating Wind Turbine
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作者 HAN Yanqing LE Conghuan +1 位作者 ZHANG Puyang XU Shengnan 《Journal of Ocean University of China》 CAS CSCD 2024年第1期69-79,共11页
The selection of wave force models will significantly impact the structural responses of floating wind turbines.In this study,comparisons of wave force model effects on the structural responses and fatigue loads of a ... The selection of wave force models will significantly impact the structural responses of floating wind turbines.In this study,comparisons of wave force model effects on the structural responses and fatigue loads of a semi-submersible floating wind turbine(SFWT)were conducted.Simulations were performed by employing the Morison equation(ME)with linear or second-order wave kinematics and potential flow theory(PFT)with first-or second-order wave forces.A comparison of regular waves,irregular waves,and coupled wind/waves analyses with the experimental data showed that many of the simulation results and experimental data are relatively consistent.However,notable discrepancies are found in the response amplitude operators for platform heave,tower base bending moment,and tension in mooring lines.PFT models give more satisfactory results of heave but more significant discrepan-cies in tower base bending moment than the ME models.In irregular wave analyses,low-frequency resonances were captured by PFT models with second-order difference-frequency terms,and high-frequency resonances were captured by the ME models or PFT models with second-order sum-frequency terms.These force models capture the response frequencies but do not reasonably predict the response amplitudes.The coupled wind/waves analyses showed more satisfactory results than the wave-only analyses.However,an important detail to note is that this satisfactory result is based on the overprediction of wind-induced responses. 展开更多
关键词 floating wind turbine wave force model potential flow theory Morison equation second-order wave forces
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An extended social force model on unidirectional flow considering psychological and behavioral impacts of hazard source
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作者 邓凯丰 李梦 +1 位作者 胡祥敏 陈涛 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期567-576,共10页
An accurate assessment of the evacuation efficiency in case of disasters is of vital importance to the safety design of buildings and street blocks.Hazard sources not only physically but psychologically affect the ped... An accurate assessment of the evacuation efficiency in case of disasters is of vital importance to the safety design of buildings and street blocks.Hazard sources not only physically but psychologically affect the pedestrians,which may further alter their behavioral patterns.This effect is especially significant in narrow spaces,such as corridors and alleys.This study aims to integrate a non-spreading hazard source into the social force model following the results from a previous experiment and simulation,and to simulate unidirectional pedestrian flows over various crowd densities and clarity–intensity properties of the hazard source.The integration include a virtual repulsion force from the hazard source and a decay on the social force term.The simulations reveal(i)that the hazard source creates virtual bottlenecks that suppress the flow,(ii)that the inter-pedestrian push forms a stabilisation phase on the flow-density curve within medium-to-high densities,and(iii)that the pedestrians are prone to a less orderly and stable pattern of movement in low clarity–intensity scenarios,possibly with lateral collisions passing the hazard source. 展开更多
关键词 EVACUATION social force model hazard source unidirectional pedestrian flow
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Improved Diurnal Cycle of Precipitation on Land in a Global Non-Hydrostatic Model Using a Revised NSAS Deep Convective Scheme
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作者 Yifan ZHAO Xindong PENG +1 位作者 Xiaohan LI Siyuan CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1217-1234,共18页
In relatively coarse-resolution atmospheric models,cumulus parameterization helps account for the effect of subgridscale convection,which produces supplemental rainfall to the grid-scale precipitation and impacts the ... In relatively coarse-resolution atmospheric models,cumulus parameterization helps account for the effect of subgridscale convection,which produces supplemental rainfall to the grid-scale precipitation and impacts the diurnal cycle of precipitation.In this study,the diurnal cycle of precipitation was studied using the new simplified Arakawa-Schubert scheme in a global non-hydrostatic atmospheric model,i.e.,the Yin-Yang-grid Unified Model for the Atmosphere.Two new diagnostic closures and a convective trigger function were suggested to emphasize the job of the cloud work function corresponding to the free tropospheric large-scale forcing.Numerical results of the 0.25-degree model in 3-month batched real-case simulations revealed an improvement in the diurnal precipitation variation by using a revised trigger function with an enhanced dynamical constraint on the convective initiation and a suitable threshold of the trigger.By reducing the occurrence of convection during peak solar radiation hours,the revised scheme was shown to be effective in delaying the appearance of early-afternoon rainfall peaks over most land areas and accentuating the nocturnal peaks that were wrongly concealed by the more substantial afternoon peak.In addition,the revised scheme enhanced the simulation capability of the precipitation probability density function,such as increasing the extremely low-and high-intensity precipitation events and decreasing small and moderate rainfall events,which contributed to the reduction of precipitation bias over mid-latitude and tropical land areas. 展开更多
关键词 cumulus parameterization diurnal cycle of precipitation large-scale dynamic forcing global non-hydrostatic atmospheric model performance verification
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Analytical Solutions for Testing of Baroclinic and Wind-Driven Three-Dimensional Hydrodynamic Models
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作者 Cheng He 《Journal of Applied Mathematics and Physics》 2024年第8期2866-2884,共19页
It is always a challenge for a model developer to verify a three-dimensional hydrodynamic model, especially for the baroclinic term over variable topography, due to a lack of observational data sets or suitable analyt... It is always a challenge for a model developer to verify a three-dimensional hydrodynamic model, especially for the baroclinic term over variable topography, due to a lack of observational data sets or suitable analytical solutions. In this paper, exact solutions for the periodic forcing by surface heat flux and wind stress are given by solving the linearized equations of motion neglecting the rotation, advection and horizontal diffusion terms. The temperature at the bottom is set to a prescribed periodic value and a slip condition on flow is enforced at the bottom. The geometry of the quarter annulus, which has been extensively studied for two- and three-dimensional analytical solutions of unstratified water bodies, is used with a general power law variation of the bottom slope in the radial direction and is constant in the azimuthal direction. The analytical solutions are derived in a cylindrical coordinate system, which describes the three-dimensional fluid field in a Cartesian coordinate system. The results presented in this paper should provide a foundation for studying and verifying the baroclinic term over a varied topography in a three-dimensional numerical model. 展开更多
关键词 3D model Baroclinic Force Analytical Solutions model Verification
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Electrostatic Attraction and Repulsion Explained and Modelled Mathematically Using Classical Physics—A Detailed Mechanism Based on Particle Wave Functions
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1050-1062,共13页
The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has... The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has been no mechanistic explanation that reveals what causes the charged particles to accelerate, either towards or away from each other. This paper gives a detailed explanation of the phenomena of electrical attraction and repulsion based on my previous work that determined the exact wave-function solutions for both the Electron and the Positron. It is revealed that the effects are caused by wave interactions between the wave functions that result in Electromagnetic reflections of parts of the particle’s wave functions, causing a change in their momenta. 展开更多
关键词 ELECTROSTATIC Electron POSITRON COULOMB Force ATTRACTION REPULSION Wave Function Electric Magnetic Radiation Pressure Shell theOREM 3D Computer model Quantum
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Research on the Coupled and Coordinated Development of Tourism and Transport in Chengdu City
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作者 Min Kang Qiguang Lv 《Proceedings of Business and Economic Studies》 2024年第3期6-15,共10页
Based on a total of 16 indicators selected from the tourism and transport industries,an evaluation index system of the coupling and coordination development level of tourism and transport is constructed.The entropy va... Based on a total of 16 indicators selected from the tourism and transport industries,an evaluation index system of the coupling and coordination development level of tourism and transport is constructed.The entropy value method and the coupling coordination degree model are used to conduct an empirical study on the development level and coupling coordination level of the transport and tourism industries in Chengdu City from 2011 to 2020.The results show that,on the whole,the coupling coordination degree of transport and tourism in Chengdu is poor and has been in a state of mild to moderate dysfunction.The development level of tourism lagged behind the development of transport from 2011 to 2012,and the two were in a state of mild dysfunction.However,from 2013 onwards,the development level of tourism was prioritized over the development level of transport.This shift caused the coupling coordination degree of the two industries to decline sharply to 0.23305 in 2013.The development level of the tourism industry increased again,reaching 0.34206 in 2019,which marked an improvement.Consequently,the coordination degree of the transport and tourism industries evolved from moderate dislocation to mild dislocation.Finally,the results of the empirical research are analyzed,and corresponding suggestions are put forward to promote the sustainable growth of the transport and tourism industries in Chengdu City.These suggestions aim to improve the coupled and coordinated development level of the two industries. 展开更多
关键词 Coupling coordination Chengdu city Transport industry Tourism industry Entropy value method Coupling coordination degree model
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Elucidating Dominant Factors Affecting Land Surface Hydrological Simulations of the Community Land Model over China 被引量:1
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作者 Jianguo LIU Zong-Liang YANG +4 位作者 Binghao JIA Longhuan WANG Ping WANG Zhenghui XIE Chunxiang SHI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第2期235-250,共16页
In order to compare the impacts of the choice of land surface model(LSM)parameterization schemes,meteorological forcing,and land surface parameters on land surface hydrological simulations,and explore to what extent t... In order to compare the impacts of the choice of land surface model(LSM)parameterization schemes,meteorological forcing,and land surface parameters on land surface hydrological simulations,and explore to what extent the quality can be improved,a series of experiments with different LSMs,forcing datasets,and parameter datasets concerning soil texture and land cover were conducted.Six simulations are run for the Chinese mainland on 0.1°×0.1°grids from 1979 to 2008,and the simulated monthly soil moisture(SM),evapotranspiration(ET),and snow depth(SD)are then compared and assessed against observations.The results show that the meteorological forcing is the most important factor governing output.Beyond that,SM seems to be also very sensitive to soil texture information;SD is also very sensitive to snow parameterization scheme in the LSM.The Community Land Model version 4.5(CLM4.5),driven by newly developed observation-based regional meteorological forcing and land surface parameters(referred to as CMFD_CLM4.5_NEW),significantly improved the simulations in most cases over the Chinese mainland and its eight basins.It increased the correlation coefficient values from 0.46 to 0.54 for the SM modeling and from 0.54 to 0.67 for the SD simulations,and it decreased the root-mean-square error(RMSE)from 0.093 to 0.085 for the SM simulation and reduced the normalized RMSE from 1.277 to 0.201 for the SD simulations.This study indicates that the offline LSM simulation using a refined LSM driven by newly developed observation-based regional meteorological forcing and land surface parameters can better model reginal land surface hydrological processes. 展开更多
关键词 hydrological simulations land surface model meteorological forcing land surface parameters UNCERTAINTY
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Simulation of Cement Hydration and Porous Structures by the Hydration-Pixel Probability Model
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作者 TIAN Cong WEI Xiaosheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第5期1044-1055,共12页
This research proposes a new pixel-based model called the hydration-pixel probability model which aims to simplify cement hydration as a probability problem.The hydration capacity of cement,the solution within pores,a... This research proposes a new pixel-based model called the hydration-pixel probability model which aims to simplify cement hydration as a probability problem.The hydration capacity of cement,the solution within pores,and the difiusion of solid particles are represented by three probability functions derived from experimental data obtained through electrical resistivity and hydration heat measurements.The principle of the model is relatively simple,and the parameters have clear physical meanings.In this research,the porous structures of difierent cement pastes with w/c ratios of 0.3,0.4,and 0.5 are investigated.The results indicate that the porosity of the cement paste decreases during the first few hours,followed by a rapid decline,and eventually reaches a steady state.The porosity of the paste decreases as w/c ratio decreases,and the rate of decrease is more rapid in the early stages.Referring to the porosity curves,the average degree of hydration and depth of hydration can be derived.The simulation results show that the hydration degree of paste composed of irregular particles is higher than that of the paste composed of round particles.The trend in the development of the average hydration depth is similar to that of the average hydration degree.Upon analyzing the average growth rate of the hydration depth,it is observed that there are two peaks in the curves,which correspond to the three characteristic points in the electrical resistivity test. 展开更多
关键词 cement hydration model POROSITY hydration degree SIMULATION
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Direct measurement and theoretical prediction model of interparticle adhesion force between irregular planetary regolith particles
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作者 Heping Xie Qi Wu +3 位作者 Yifei Liu Yachen Xie Mingzhong Gao Cunbao Li 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第11期1425-1436,共12页
Interparticle adhesion force has a controlling effect on the physical and mechanical properties of planetary regolith and rocks.The current research on the adhesion force of planetary regolith and rock particles has b... Interparticle adhesion force has a controlling effect on the physical and mechanical properties of planetary regolith and rocks.The current research on the adhesion force of planetary regolith and rock particles has been primarily based on the assumption of smooth spherical particles to calculate the intergranular adhesion force;this approach lacks consideration for the adhesion force between irregular shaped particles.In our study,an innovative approach was established to directly measure the adhesion force between the arbitrary irregular shaped particles;the probe was modified using simulated lunar soil particles that were a typical representation of planetary regolith.The experimental results showed that for irregular shaped mineral particles,the particle size and mineral composition had no significant influence on the interparticle adhesion force;however,the complex morphology of the contact surface predominantly controlled the adhesion force.As the contact surface roughness increased,the adhesion force gradually decreased,and the rate of decrease gradually slowed;these results were consistent with the change trend predicted via the theoretical models of quantum electrodynamics.Moreover,a theoretical model to predict the adhesion force between the irregular shaped particles was constructed based on Rabinovich’s theory,and the prediction results were correlated with the experimental measurements. 展开更多
关键词 Planetary regolith Adhesion force Particle morphology Prediction model
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Existence of Forced Waves and Their Asymptotic for Leslie-Gower Prey-Predator Model with Nonlocal Effects under Shifting Environment
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作者 Qingru Guo Hongmei Cheng 《Journal of Applied Mathematics and Physics》 2023年第6期1737-1754,共18页
In this paper, we prove the existence of forced waves for Leslie-Gower prey-predator model with nonlocal effects under shifting environment. By constructing a pair of upper and lower solutions with the method of monot... In this paper, we prove the existence of forced waves for Leslie-Gower prey-predator model with nonlocal effects under shifting environment. By constructing a pair of upper and lower solutions with the method of monotone iteration, we can obtain the existence of forced waves for any positive constant shifting speed. Finally, we show the asymptotical behavior of traveling wave fronts in two tails. 展开更多
关键词 Leslie-Gower Prey-Predator model Nonlocal Effects Shifting Environment Forced Waves
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Analysis of Major Driving Forces of Ecological Footprint Based on the STRIPAT Model and RR Method:A Case of Sichuan Province,Southwest China 被引量:6
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作者 TANG Wei ZHONG Xianghao LIU Shaoquan 《Journal of Mountain Science》 SCIE CSCD 2011年第4期611-618,共8页
The Ecological Footprint(EF) equation provides useful accounting to analyze the relationship between human activities and the environment.Knowledge of the specific forces driving EF is not fully understood but the STI... The Ecological Footprint(EF) equation provides useful accounting to analyze the relationship between human activities and the environment.Knowledge of the specific forces driving EF is not fully understood but the STIRPAT model provides a simple framework for decomposing the impact of human activities on environment.We applied the EF model in Sichuan Province,China to assess the impact of human activities.The per capita EF increased by 2 fold in the 14 years between 1995 and 2008,but ecological capacity decreased in the same period,suggesting that the biologically productive area of Sichuan Province is inadequate to sustain human activities.According to the refined STIRPAT model,the hypothesized driving forces of EF include population size(P),GDP per capita(A1),quadratic term of GDP per capita(A2),percentage of GDP from industry(T1) and urbanization rate(T2).However,the multi-collinearity among these drivers could be a substantial problem which may reveal negative effect in the final results.Application of the Ridge Regression(RR) method to fit the STIRPAT model had the advantage of being able to avoid the collinearity among independent variables.The results showed that population is the principal driving force of EF variation in Sichuan Province and that urbanization and industrialization also have a positive association with the EF.Analysis of affluence elasticity(EEA) showed that the relationship betweenEF and economic growth was not curvilinear,suggesting that variation of EF does not follow an Environmental Kuznets Curve relative to economic growth in Sichuan Province. 展开更多
关键词 Ecological footprint STIRTPAT model Ridge Regression Major driving forces Sichuan Province China
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A flexible multi-body model of a surface miner for analyzing the interaction between rock-cutting forces and chassis vibrations 被引量:1
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作者 Alessandro Medolago Stefano Melzi 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第3期365-375,共11页
The discontinuous nature of rock cutting can easily cause unwanted vibrations in the structure of a surface miner.If these vibrations are not properly addressed,the related stress cycles can gradually damage the chass... The discontinuous nature of rock cutting can easily cause unwanted vibrations in the structure of a surface miner.If these vibrations are not properly addressed,the related stress cycles can gradually damage the chassis resulting in fatigue failures.These events can seriously undermine the safety of operators and digging operations may be stopped for days,with an obvious economic impact.This work presents an analysis of the dynamics of a surface miner,focusing on the interaction between cutting machine dynamics and cutting forces,which is a new approach for this type of machine.For this purpose,the authors developed a numerical model of the cutting process made up of(1)a multi-body model of the cutting machine,which takes into account the chassis's flexibility;(2)a model of the rotating cutting head;and(3)a model of the interaction between the cutting head and rock,based on Shao's model.The model was compared with experimental results and then used to investigate the effects of cutting speed and cutting depth on the machine dynamics. 展开更多
关键词 Surface miner Flexible multi-body model VALIDATION Cutting forces Chassis vibrations
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Analysis to the Driving Force Model and Driving Factor on the Utilized Changes of Cultivated Land in Gonghe County 被引量:14
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作者 俞文政 刘丹 +1 位作者 祁英香 史军 《Agricultural Science & Technology》 CAS 2009年第4期178-182,共5页
Using gradually regression analysis to establish the driving force model of utilized change of cultivated land in Gonghe County, and using path analysis, correlation analysis, partial correlation analysis and system d... Using gradually regression analysis to establish the driving force model of utilized change of cultivated land in Gonghe County, and using path analysis, correlation analysis, partial correlation analysis and system dynamics method to inspect the effect of driving changing on cultivated land change under different change situations. Driving factors, action mechanism and process of utilized change of cultivated land were analyzed from the county territory scale level. At last, some corresponding policies and measures were put forward. 展开更多
关键词 Gonghe County Utilized Change of cultivated land Driving force model Driving factors
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"universe collapse model"and its roles in the unification of four fundamental forces and the origin and the evolution of the universe
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作者 Jiapei Dai 《Natural Science》 2012年第4期199-203,共5页
To unify the four known fundamental forces and provide an explanation for the origin and the evolution of the universe are two long-term goals of theoretical physics. Here a “universe collapse model” has been propos... To unify the four known fundamental forces and provide an explanation for the origin and the evolution of the universe are two long-term goals of theoretical physics. Here a “universe collapse model” has been proposed. The universe consists of Matter and No-matter. No-matter is the universal energy that constructs a consistent universe field, presenting a spiral wave motion at the speed of light at the small scale. The partial collapse of the universal energy forms the particles of the universal energy in a variety of sizes, which are called as the elementary particles. These elementary particles form atom and matter, which construct the galaxies. The collapse of the universe field induces the formation of the universe collapse potential (UCP) and universe collapse force (UCF), and the later is represented by four different aspects of the fundamental forces at the large or small scales. The mathematical equation and the derivation of UCP and UCF are described, and possible experimental tests are also suggested. Therefore, this new model may give a novel explanation for the unification of four fundamental forces and the origin and the evolution of the universe. 展开更多
关键词 UNIVERSE COLLAPSE model Field theories Beyond Standard model String Field theory Grand Unification model FUNDAMENTAL forces Elementary Particles the ORIGIN and Evolution of UNIVERSE
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Analysis to the Driving Force Model and Drives Factor on the Utilized Changes of Cultivated Land in Qinghai Lake Area 被引量:5
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作者 赤旦多杰 淡乐蓉 《Agricultural Science & Technology》 CAS 2009年第6期150-154,共5页
Using path analysis, correlation analysis, partial correlation analysis and system dynamics method to study the driving force of cultivated land in Qinghai Lake Area, and using gradually regression analysis to establi... Using path analysis, correlation analysis, partial correlation analysis and system dynamics method to study the driving force of cultivated land in Qinghai Lake Area, and using gradually regression analysis to establish the driving force model of utilized change of cultivated land. Driving factors, action mechanism and process of utilized change of cultivated land were analyzed, and the differences during all factors were compared. The study provides some decision basis for sustainable utilization and management of land resources in Qinghai Lake Area. 展开更多
关键词 Qinghai Lake Area Utilized change of cultivated land Driving force model Driving factors
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An extended micromechanical-based plastic damage model for understanding water effects on quasi-brittle rocks
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作者 Qiaojuan Yu Shigui Du +3 位作者 Qizhi Zhu Zhanyou Luo Sili Liu Lunyang Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期289-304,共16页
Water effects on the mechanical properties of rocks have been extensively investigated through experiments and numerical models.However,few studies have established a comprehensive link between the microscopic mechani... Water effects on the mechanical properties of rocks have been extensively investigated through experiments and numerical models.However,few studies have established a comprehensive link between the microscopic mechanisms of water-related micro-crack and the constitutive behaviors of rocks.In this work,we shall propose an extended micromechanical-based plastic damage model for understanding weakening effect induced by the presence of water between micro-crack’s surfaces on quasi-brittle rocks,based on the Mori-Tanaka homogenization and irreversible thermodynamics framework.Regarding the physical mechanism,water strengthens micro-crack propagation,which induces damage evolution during the pre-and post-stage,and weakens the elastic effective properties of rock matrix.After proposing a special calibration procedure for the determination of model parameters based on the laboratory compression tests,the proposed micromechanical-based model is verified by comparing the model predictions to the experimental results.The model effectively captures the mechanical behaviors of quasibrittle rocks subjected to the weakening effects of water. 展开更多
关键词 Water MICRO-CRACK DAMAGE MICRO-MECHANICS Constitutive model Cohesive force
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Construction of Tourist Satisfaction Degree Evaluation Model in Western Tourist Area by Performance Prism and Fuzzy Comprehensive Evaluation Method——with Lijiang in Yunnan Province as the Study Case
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作者 蒋蓉华 焦俊刚 刘曲华 《Journal of Landscape Research》 2010年第4期64-68,共5页
Starting from the utilization and protection of local knowledge, with the performance prism as the framework, the evaluation index system of tourist satisfaction degree was established. The weight was determined by us... Starting from the utilization and protection of local knowledge, with the performance prism as the framework, the evaluation index system of tourist satisfaction degree was established. The weight was determined by using AHP method. Finally, the investigating result was judged with fuzzy comprehensive evaluation method, the evaluation model of tourist satisfaction degree in western tourist area was built, and the case study was carried out. With Lijiang in Yunnan Province as example, according to AHP method, five dimensions weight of the performance prism, various KPI weight and consistency were obtained, fuzzy evaluation on tourist satisfaction degree was conducted. The results showed that the overall was satisfactory, but there were still some problems. Aiming at the utilization and protection of local knowledge, some corresponding countermeasures were put forward which will benefit for further development of tourism in Lijiang of Yunnan Province. 展开更多
关键词 Toursit SATISFACTION degree Performance PRISM Fuzzy comprehensive EVALUATION EVALUATION model
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Dynamic-based model for calculating the boulder impact force in debris flow
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作者 YANG Chaoping ZHANG Shaojie +2 位作者 YIN Yueping YANG Hongjuan WEI Fangqiang 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1930-1940,共11页
The boulder impact force in debris flow is generally calculated by static methods such as the cantilever beam models.However,these methods cannot describe the dynamic scenario of boulder collision on structures,so the... The boulder impact force in debris flow is generally calculated by static methods such as the cantilever beam models.However,these methods cannot describe the dynamic scenario of boulder collision on structures,so the inertia and damping effects of the structures are not involved causing an overestimation on the boulder impact force.In order to address this issue,a dynamic-based model for calculating the boulder impact force of a debris flow was proposed in this study,and the dynamic characteristics of a cantilever beam with multiple degrees of freedom under boulder collision were investigated.By using the drop-weight method to simulate boulders within debris flow,seven experiments of drop-weight impacting the cantilever beam were used to calibrate the error of the dynamicbased model.Results indicate that the dynamic-based model is able to reconstruct the impact force history on the cantilever beam during impact time and the error of dynamic-based model is 15.3%in calculating boulder impact force,significantly outperforming the cantilever beam model’s error of 285%.Therefore,the dynamic-based model can overcome the drawbacks of the static-based models and provide a more reliable theoretical foundation for the engineering design of debris flow control structures. 展开更多
关键词 Debris flow Impact force Boulder collision Dynamic-based model Engineering design
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Numerical simulations of Atlantic meridional overturning circulation(AMOC)from OMIP experiments and its sensitivity to surface forcing
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作者 Xiaowei WANG Yongqiang YU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期454-467,共14页
Atlantic meridional overturning circulation(AMOC)plays an important role in transporting heat meridionally in the Earth’s climate system and is also a key metrical tool to verify oceanic general circulation models.Tw... Atlantic meridional overturning circulation(AMOC)plays an important role in transporting heat meridionally in the Earth’s climate system and is also a key metrical tool to verify oceanic general circulation models.Two OMIP(Ocean Model Intercomparison Project phase 1 and 2)simulations with LICOM3(version 3 of the LASG/IAP Climate System Ocean Model)developed at the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG),Institute of Atmospheric Physics(IAP),are compared in this study.Both simulations well reproduce the fundamental characteristics of the AMOC,but the OMIP1 simulation shows a significantly stronger AMOC than the OMIP2 simulation.Because the LICOM3 configurations are identical between these two experiments,any differences between them must be attributed to the surface forcing data.Further analysis suggests that sea surface salinity(SSS)differences should be mainly responsible for the enhanced AMOC in the OMIP1 simulation,but sea surface temperature(SST)also play an unignorable role in modulating AMOC.In the North Atlantic,where deep convection occurs,the SSS in OMIP1 is more saline than that in OMIP1.We find that in the major region of deep convection,the change of SSS has more significant effect on density than the change of SST.As a result,the SSS was more saline than that in OMIP2,leading to stronger deep convection and subsequently intensify the AMOC.We conduct a series of numerical experiments with LICOM3,and the results confirmed that the changes in SSS have more significant effect on the strength of AMOC than the changes in SST. 展开更多
关键词 oceanic general circulation model(OGCM) Atlantic meridional overturning(AMOC) surface forcing deep convection
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