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西藏交通警察道路执法工作的风险与防范
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作者 尼桑拉 《时代汽车》 2024年第12期184-186,共3页
西藏自治区自然、地理与气候环境复杂且特殊,道路交通环境相对恶劣,这导致当地交通警察道路执法工作面临诸多风险,包括警员人身安全和执法效能等风险。对此,文章对西藏交通警察道路执法工作风险进行了调查分析,从地区环境、警员安全意... 西藏自治区自然、地理与气候环境复杂且特殊,道路交通环境相对恶劣,这导致当地交通警察道路执法工作面临诸多风险,包括警员人身安全和执法效能等风险。对此,文章对西藏交通警察道路执法工作风险进行了调查分析,从地区环境、警员安全意识与技能、执法装备、社会宣传和教育等角度探讨了相关风险的成因,针对性相关风险成因,提出从优化警力配置与道路信息推送、加强警员培训、完善警务装备、加强法治化宣传教育等工作来消除相关风险,以期保障警员安全并改善西藏交通环境。 展开更多
关键词 西 harsh which leads to the local trac POLICE road LAW ENforceMENT work to face a lot of RISKS including the personal SAFETY of the POLICE ocers and LAW ENforceMENT eectiveness and other risks. In this regard this paper investigates and analyzes the RISKS of road LAW ENforceMENT work of the Xi Zang trac POLICE discusses the causes of the RISKS from the perspectives of regional environment POLICE SAFETY awareness and skills LAW ENforceMENT equipment social publicity and education and proposes to eliminate the RISKS by optimizing the allocation of POLICE force and road information delivery strengthening POLICE training improving POLICE equipment and strengthening the rule of LAW publicity and education etc. so as to guarantee the SAFETY of POLICE ocers and improve the eectiveness of LAW ENforceMENT so as to ensure the SAFETY of POLICE ocers and improve the trac environment in Xi Zang.
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Self-assembly of perovskite nanocrystals:From driving forces to applications
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作者 Yi Li Fei Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期561-578,I0013,共19页
Self-assembly of metal halide perovskite nanocrystals(NCs)into superlattices can exhibit unique collective properties,which have significant application values in the display,detector,and solar cell field.This review ... Self-assembly of metal halide perovskite nanocrystals(NCs)into superlattices can exhibit unique collective properties,which have significant application values in the display,detector,and solar cell field.This review discusses the driving forces behind the self-assembly process of perovskite NCs,and the commonly used self-assembly methods and different self-assembly structures are detailed.Subsequently,we summarize the collective optoelectronic properties and application areas of perovskite superlattice structures.Finally,we conclude with an outlook on the potential issues and future challenges in developing perovskite NCs. 展开更多
关键词 SELF-ASSEMBLY Metal halide perovskite NANOCRYSTALS driving forces
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A Workable Solution for Reducing the Large Number of Vehicle and Pedestrian Accidents Occurring on a Yellow Light
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作者 Pranav Gupta Silki Arora 《Journal of Transportation Technologies》 2024年第1期82-87,共6页
Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada... Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada, during 2019, the National Collision Database shows that 28% of traffic fatalities and 42% of serious injuries occurred at intersections. Likewise, the U.S. National Highway Traffic Administration (NHTSA) found that about 40% of the estimated 5,811,000 accidents in the U.S. during the year studied were intersection-related crashes. In fact, a major survey by the car insurance industry found that nearly 85% of drivers could not identify the correct action to take when approaching a yellow traffic light at an intersection. One major reason for these accidents is the “yellow light dilemma,” the ambiguous situation where a driver should stop or proceed forward when unexpectedly faced with a yellow light. This situation is even further exacerbated by the tendency of aggressive drivers to inappropriately speed up on the yellow just to get through the traffic light. A survey of Canadian drivers conducted by the Traffic Injury Research Foundation found that 9% of drivers admitted to speeding up to get through a traffic light. Another reason for these accidents is the increased danger of making a left-hand turn on yellow. According to the National Highway Traffic Safety Association (NHTSA), left turns occur in approximately 22.2% of collisions—as opposed to just 1.2% for right turns. Moreover, a study by CNN found left turns are three times as likely to kill pedestrians than right turns. The reason left turns are so much more likely to cause an accident is because they take a driver against traffic and in the path of oncoming cars. Additionally, most of these left turns occur at the driver’s discretion—as opposed to the distressingly brief left-hand arrow at busy intersections. Drive Safe Now proposes a workable solution for reducing the number of accidents occurring during a yellow light at intersections. We believe this fairly simple solution will save lives, prevent injuries, reduce damage to public and private property, and decrease insurance costs. 展开更多
关键词 Traffic Accidents Yellow Light Traffic Light Signals INTERSECTION Crashes Collision Traffic Fatalities Traffic Injuries Vehicles SAFETY Speed Limit driving Pedestrians Bicyclists MOTORCYCLISTS Caution Line Yellow Light Dilemma Left Hand Turn on Yellow Distance Smart Road Technology Signs Signage Autonomous Vehicles AVs Road Safety IoT Internet of Things Infrastructure Accident Reduction driving Habits Stop Line Red Light Jumping Pedestrian Safety Caution Light Stopping at Intersection Safety at Intersections
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Research on the Spatio-Temporal Evolution and Driving Forces of Green Spaces in the Central Urban Area of Zunyi City
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作者 Juan Du 《Journal of Architectural Research and Development》 2024年第4期8-16,共9页
Green space,as a medium for carrying out urban functions and guiding urban development,is becoming a scarce resource along with the urbanization process and the intensification of environmental problems.In the face of... Green space,as a medium for carrying out urban functions and guiding urban development,is becoming a scarce resource along with the urbanization process and the intensification of environmental problems.In the face of the spatial mismatch between high demand and low supply,it is of great significance to clarify the evolution mechanism of green space to undertake national spatial planning,protect the natural strategic resources in the urban fringe area,and promote the sustainable development of the“three living spaces.”The study focuses on the Zunyi City Center,selecting the 20 years of rapid development following its establishment as a city as the study period.It explores the dynamic evolution of green space and the main driving forces during different periods using remote-sensing image data.The study shows that from 2003 to 2023,the total scale of green space has an obvious decreasing trend along with the expansion of the urban built-up area.A large amount of arable land is being converted to construction land,resulting in a sudden decrease in arable land area.In the past 10 years,the comprehensive land use dynamics have accelerated.Still,the spatial difference has gradually narrowed,indicating that the overall development intensity of Zunyi City’s central urban area has increased.There is a gradual spread of the trend to the hilly areas.The limiting effect of the mountainous natural environment on the city’s development has gradually diminished under the superposition of external factors,such as economic development,industrial technological upgrading,and policy orientation so the importance of the effective protection and rational utilization of urban green space has become more prominent. 展开更多
关键词 Green space Spatio-temporal evolution driving force Zunyi city center
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The Integration of Modern Electronic Technology and E-Commerce:the Driving Force of Innovation Development
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作者 Yongchang Cai 《Journal of Educational Theory and Management》 2024年第2期6-10,共5页
In the 21st century,which is known as the age of information,the integration of electronic technology and e-commerce has become an irreversible trend in the field of business.This trend not only promotes the innovativ... In the 21st century,which is known as the age of information,the integration of electronic technology and e-commerce has become an irreversible trend in the field of business.This trend not only promotes the innovative development of e-commerce,but also brings unprecedented opportunities and challenges for enterprises.With the continuous development and popularization of Internet technology,more and more people choose to carry out shopping,payment and other consumption activities through e-commerce platforms,which also provides merchants with a broader market space and more sales channels.At the same time,e-commerce also brings more convenience and choice to consumers,making it easier for consumers to obtain the goods and services they need.However,the development of e-commerce has also brought some new challenges,such as how to ensure the quality of goods,how to protect consumer privacy and so on.Therefore,enterprises and government departments need to strengthen the supervision and management of e-commerce to ensure its healthy and orderly development.In general,the integration of electronic technology and e-commerce has become an important trend in today’s business field,which brings both opportunities and challenges to enterprises. 展开更多
关键词 Electronic technology Electronic commerce Innovation and development driving force
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Analysis to driving forces of land use change in Lu’an mining area 被引量:2
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作者 LIU Chang-hua, MA Xiao-xiao School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo 454003, China 《中国有色金属学会会刊:英文版》 CSCD 2011年第S3期727-732,共6页
By selecting impact factors of driving force and formulating evaluation criteria of the impacts, the evaluation system of corresponding driving force impact of land use change was established. Taking Lu'an mining ... By selecting impact factors of driving force and formulating evaluation criteria of the impacts, the evaluation system of corresponding driving force impact of land use change was established. Taking Lu'an mining area as an example, the specific impact factors of coal mine were comprehensively evaluated and analyzed in order to carry out qualitative and quantitative analysis for the driving force of mining-land use change. The principal component analysis shows that the social and economic development in mining area from 2000 to 2007 demonstrates continuous accelerate trends, and the impacts of its overall driving force to land use change are increased gradually. The socio-economic factors have more impacts to mining-land use change than those of the natural resources. The main driving force of mining-land use change also include population, technological progress and policy. 展开更多
关键词 MINING area LAND use change driving force evaluation FACTOR principal component ANALYSIS
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Evaluation and Driving Force Analysis of Cultivated Land Quality in Black Soil Region of Northeast China 被引量:1
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作者 WANG Mingchang LIU Xingnan +4 位作者 LIU Ziwei WANG Fengyan LI Xiaoyan HOU Guanglei ZHAO Shijun 《Chinese Geographical Science》 SCIE CSCD 2023年第4期601-615,共15页
Cultivated land is an important natural resource to ensure food,ecological and economic security.The cultivated land quality evaluation(CQE)is greatly significant for protecting and managing cultivated land.In this st... Cultivated land is an important natural resource to ensure food,ecological and economic security.The cultivated land quality evaluation(CQE)is greatly significant for protecting and managing cultivated land.In this study,320 counties in the black soil region of Northeast China(BSRNC)represent the research units used to construct the CQE system measuring the soil properties(SP),cultivated land productivity(CLP),ecological environment(EE)and social economy(SE).The total of 19 factors were selected to calculate the integrated fertility index(IFI)and divided into grades.Simultaneously,we used the coupling coordination degree model to comprehensively analyze the spatial pattern of the cultivated land quality(CLQ)in the BSRNC,and use the structural equation model(SEM)to analyze the driving mechanism.The results show the following:1)The CLQ of 262 counties in the BSRNC is in a state of coupling and coordination,and the coupling and coordination degree presents a spatial distribution pattern of‘high in the southwest and northeast,low in the northwest and southeast’.The coordinated development degree of 271 counties is between 0.4 and 0.6,which is in a transitional state between coordination and disorder.2)The CLQ in the BSRNC is generally good,with an average grade of 3.High-quality cultivated land accounts for 58.45%of all counties,middle-and upper-quality cultivated land accounts for 27.05%,and poor-quality cultivated land accounts for 14.49%.3)The SEM analysis shows that the SP,CLP,EE,and SE all influence the CLQ.Among them,the SP has the largest driving force on the CLQ,while the SE has the smallest driving force on it.The results confirm that the main factors affecting the evaluation results are crop productivity level,normalized difference vegetation index,ratio vegetation index,difference vegetation index,and organic carbon content.When implementing protection measures in counties with a low CLQ,considering a balanced coordination of multiple systems and reasonably controlling the quality degradation are important.This study provides the current situation and driving factors of the CLQ in the BSRNC and will play an important role in black soil governance and utilization. 展开更多
关键词 cultivated land quality evaluation(CQE) black soil region of Northeast China(BSRNC) coupling coordination degree model structural equation model(SEM) driving forces
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Driving forces and their relative contributions to hydrocarbon expulsion from deep source rocks: A case of the Cambrian source rocks in the Tarim Basin
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作者 Bo Pang Jun-Qing Chen +2 位作者 Xiong-Qi Pang Tao Hu Yue Sheng 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期20-33,共14页
To thoroughly understand the dynamic mechanism of hydrocarbon expulsion from deep source rocks,in this study,five types of hydrocarbon expulsion dynamics(thermal expansion,hydrocarbon diffusion,compaction,product volu... To thoroughly understand the dynamic mechanism of hydrocarbon expulsion from deep source rocks,in this study,five types of hydrocarbon expulsion dynamics(thermal expansion,hydrocarbon diffusion,compaction,product volume expansion,and capillary pressure difference(CPD))are studied.A model is proposed herein to evaluate the relative contribution of different dynamics for hydrocarbon expulsion using the principle of mass balance,and the model has been applied to the Cambrian source rocks in the Tarim Basin.The evaluation results show that during hydrocarbon expulsion from the source rocks,the relative contribution of CPD is the largest(>50%),followed by compaction(10%-40%),product volume expansion(5%-30%),and thermal expansion(2%-20%).The relative contribution of diffusion to hydrocarbon expulsion is minimal(<10%).These results demonstrate that CPD plays an important role in the hydrocarbon expulsion process of deep source rocks.The hydrocarbon expulsion process of source rocks can be categorized into three stages based on the contribution of different dynamics to the process:the first stage is dominated by compaction and diffusion to expel hydrocarbons,the second stage is dominated by product volume expansion and CPD,and the third stage is dominated by product volume expansion and CPD.This research offers new insights into hydrocarbon exploration in tight oil and gas reservoirs. 展开更多
关键词 driving force Dynamic mechanism Hydrocarbon expulsion Deep oil and gas exploration Tarim Basin
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Thermodynamic re-assessment of the Mg-Gd-Y ternary system coupling with the driving forces for phase precipitations during aging process
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作者 Xiaopan Wu Changrong Li +1 位作者 Cuiping Guo Zhenmin Du 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第7期2495-2517,共23页
Based on the available experimental phase equilibrium relations and aging precipitation sequences,the Mg–Gd–Y ternary system has been thermodynamically re-assessed by means of CALPHAD technique.To simulate the exper... Based on the available experimental phase equilibrium relations and aging precipitation sequences,the Mg–Gd–Y ternary system has been thermodynamically re-assessed by means of CALPHAD technique.To simulate the experimentally reported aging precipitation sequence,α(Mg)_(SS)(supersaturated)→GP zones(D019-type,metastable)→β’-Mg_(7)Gd(c-bco,metastable)→β_(1)-Mg_(3)Gd(fcc,metastable)→β-Mg_(5)Gd(fcc,stable)near the Mg–Gd side,andα(Mg)SS(supersaturated)→β’-Mg_(7)Y(c-bco,metastable)→β-Mg_(24)Y_(5)(bcc,stable)near the Mg–Y side,the effective nucleation driving forces obtained by deducting the nucleation resistances from the thermodynamic driving forces are calculated and analyzed.Two metastable components,GP zones(D019-type)andβ’(c-bco)ordered fromα(Mg)_(SS),do not exist in the stable equilibrium phase diagram but appear in the annealing process of typical alloys.The Redlich–Kister equations are adopted to describe three solution phases,Liquid,HCP_A3 and BCC_A2.The intermediate compounds Mg_(2)Y,Mg_(24)Y_(5),Mg_(2)Gd,Mg_(3)Gd and Mg_(5)Gd are expressed by the formulas of(Mg,Y)_(2/3)(Gd,Mg,Y)_(1/3),Mg_(24/29)(Gd,Mg,Y)_(4/29)Y1/29,(Gd,Mg)_(2/3)(Gd,Mg,Y)_(1/3),(Gd,Mg)_(3/4)(Gd,Mg,Y)_(1/4)and Mg_(5/6)(Gd,Mg,Y)_(1/6),respectively.In particular,the two-sublattice models(Gd,Mg,Y)_(1/2)(Gd,Mg,Y)_(1/2),(Gd,Mg,Y)_(3/4)(Gd,Mg,Y)_(1/4)and(Gd,Mg,Y)_(7/8)(Gd,Mg,Y)_(1/8)have been respectively used to describe the stable Mg(Gd,Y)(BCC_B2)alloy compound as well as the metastable GP zones(D019-type)andβ’(c-bco)phase,in order to cope with the order-disorder transitions.A set of self-consistent thermodynamic parameters has been obtained to ensure the thermodynamic calculations well consistent with the reported experimental data,containing not only the stable equilibrium phase diagram but also the aging precipitation sequence. 展开更多
关键词 Mg-Gd-Y ternary system Thermodynamic re-assessment Aging precipitation sequence Nucleation driving force CALPHAD technique
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NASA’s EM Drive Thrust from the Forces of the Quantum Vacuum of Spacetime
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作者 Mohamed S. El Naschie 《Advances in Aerospace Science and Technology》 2018年第1期1-9,共9页
Building on the various manifestations of the forces latent in the quantum vacuum of spacetime such as Hawking’s radiation and Unruh temperature, we resolve a major paradox connected to an immensely important proposa... Building on the various manifestations of the forces latent in the quantum vacuum of spacetime such as Hawking’s radiation and Unruh temperature, we resolve a major paradox connected to an immensely important proposal by NASA scientists for constructing a practically fuelless spacecraft. In a nutshell, preliminary laboratory work shows that NASA’s electromagnetic drive project is viable and several experiments and measurements show it is real. Yet the proposal violates a fundamental principle of classical mechanics, namely Newton’s third law. The resolution of this paradox is quite straight forward in principle. It is simply the case that although the proposal seems to be based on classical mechanics and classical thinking it is only superficially so. Deep at the roots, the EM drive proposal of NASA is not classical physics but rather based on the vacuum forces of quantum cosmology and the theory of dark energy density of the universe. In fact the proposal is deeply linked to Hawking’s radiation and Unruh temperature, which is explained in some detail in the main body of the present short paper within the frame work of E-infinity Cantorian spacetime theory and D. Gross’ Heterotic superstring theory. In short the quintessence of our explanation is to regard the EM drive as a quasi electromagnetic cavity with an effective event horizon akin to that of a Hawking black hole emitting radiation causing ultimately the needed thrust to push the spacecraft forwards. In addition and by invoking fractal spacetime self similarity we show that a spacecraft will be subject to another cosmic thrust on the large scale of the entire cosmos. 展开更多
关键词 EM DRIVE Interstellar Flight Vacuum ENERGY DARK ENERGY Cantorian SPACETIME Hartle-Hawking Wave Function of the Cosmos Cantorian Plasma Quantum Cosmology Casimir-Dark ENERGY Nano Reactor Heterotic SUPERSTRINGS Equations of Ordinary and DARK ENERGY Nonlinear Dynamics and Fractals Hawking Radiation Axion Unruh Temperature
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Detection of Multi-dimensional Driving Forces of Public Environmental Concern in China:Based on Spatial Heterogeneity Perspectives 被引量:1
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作者 TONG Yun PANG Li +1 位作者 SUN Minghui HAN Junyi 《Chinese Geographical Science》 SCIE CSCD 2023年第6期1109-1126,共18页
Public environmental concern(PEC)is an important bottom-up force in building an environmentally sustainable society.Guided by attitude theory,this paper innovatively constructed a PEC evaluation index system,while int... Public environmental concern(PEC)is an important bottom-up force in building an environmentally sustainable society.Guided by attitude theory,this paper innovatively constructed a PEC evaluation index system,while introducing entropy weighted-TOPSIS(Technique for Order Preference by Similarity to Ideal Solution)to realize the assessment of PEC.Exploratory spatial data analysis was used to portray the spatio-temporal evolution patterns of PEC in 362 Chinese cities at prefecture-level and above from 2011 to 2018.Furthermore,the Geodetector model was performed to identify the multi-dimensional determinants of PEC from the perspective of spatial heterogeneity.The results indicated that:1)PEC in China exhibited a fluctuating upward trend,consistent with the spatial distribution law of‘Heihe-Tengchong Line’and‘Bole-Taipei Line’;2)the driving effect of each factor varied dynamically,but in general,economic development level,population size,industrial wastewater,and education level were the dominant driving factors explaining the spatial variation of PEC;3)risk detection revealed that four factors,government environmental regulations,PM_(2.5),vegetation coverage,and natural resource endowment,had nonlinear effects on PEC;4)the interactions between factors all demonstrated an enhancement in explaining the spatial differentiation of PEC.PEC was driven by the comprehensive interaction of four-dimensional factors of economy,society,pollutant emissions,and ecology.Among them,population agglomeration accompanied by a high level of regional economy and information technology can explain the increase in PEC to the greatest extent. 展开更多
关键词 public environmental concern(PEC) spatio-temporal variations driving factors Geodetector Baidu Index spatial heterogeneity
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The Evolution of a Karst Rocky Desertification Land Ecosystem and Its Driving Forces in the Houzhaihe Area, China 被引量:10
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作者 Yangbing Li Jing Xie +2 位作者 Guangjie Luo Hua Yang Shijie Wang 《Open Journal of Ecology》 2015年第10期501-512,共12页
Understanding the evolution of karst rocky desertification (KRD) quantitatively is essential to obtain objective knowledge about the concept of KRD and the form reason of KRD, and is useful to restore KRD land. Houzha... Understanding the evolution of karst rocky desertification (KRD) quantitatively is essential to obtain objective knowledge about the concept of KRD and the form reason of KRD, and is useful to restore KRD land. Houzhaihe area located in central plateau in Guizhou Province was studied here as a representative assemblage landform and its KRD’ s evolution and driving factors were studied, based mainly on high-resolution remote sensing image in 1963, 1978, 2005 and 2010. The KRD land comprises light KRD, moderate KRD and severe KRD. The results demonstrated that the evolution process of KRD can be divided into four modes such as unchanged, weakened, fluctuated and aggravated in the study area. The KRD with no changes from 1963 to 2010, namely, unchanged mode, accounted for 43.76% of the total area of the KRD in 2010;it distributed in the area with the slope of 15&#176 - 25&#176 and >25&#176 basically. Furthermore, the severe KRD distributed mainly in the areas within 300 - 600 m distance from settlement;when the distance away from the rural settlements was more than 900 m, the severe KRD declined, and its proportion was 28.6% and 10.6% in 1963 and 2010 respectively. In the peak-cluster depressions, located in central study area, the slope cropland with slope of 15&#176 - 25&#176 was still abounding, and was seriously rocky desertification generally. So, we propose that the existence of a large number of slope croplands is still the major driving factor of land rocky desertification. Therefore, for the rocky desertification control, the authors consider that the focal point is to alter the land use of steep-slope cropland at present. 展开更多
关键词 KARST Rocky DESERTIFICATION EVOLUTION driving Mechanism Central PLATEAU in GUIZHOU
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New Method of Natural Reserve Readjustment and Zoning Based on Land Use/Cover Change and Driving Forces—A Case Study of Tianjin Palaeocoast and Wetland National Natural Reserve
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作者 Zhenglei Xie,Xuegong Xu,Xiaofeng Duan,Lei Yan College of Urban and Environmental Sciences,Laboratory for Earth Surface Processes of Ministry of Education,Peking University,Beijing 100871,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期299-299,共1页
Natural reserve can provide ecology system with natural background for human being and has important significance for sustaining ecosystem service.The continuous damage and deterioration of ecosystem in natural reserv... Natural reserve can provide ecology system with natural background for human being and has important significance for sustaining ecosystem service.The continuous damage and deterioration of ecosystem in natural reserve caused by human activities have become one of the most serious environmental problems.The conflict between local 展开更多
关键词 palaeocoast and WETLAND NATURAL RESERVE readjustment and ZONING driving forces TIANJIN
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Driving Force Model for Non-pneumatic Elastic Wheel 被引量:3
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作者 Li Bo Zhao Youqun +3 位作者 Zang Liguo Bei Shaoyi Fu Hongxun Zhang Lanchun 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第2期231-236,共6页
In order to obtain good driving performance,a driving force model is presented for non-pneumatic elastic wheel.Brush model of pneumatic tyres is introduced and the deformations of elastic supports and tread are also t... In order to obtain good driving performance,a driving force model is presented for non-pneumatic elastic wheel.Brush model of pneumatic tyres is introduced and the deformations of elastic supports and tread are also taken into account.The longitudinal slip rate is redefined.The grounding pressure distribution of elastic wheels is analyzed and corrected according to speed,temperature and stiffness.Then rolling resistance equation is developed.Finally,simulation is conducted by software CarSim,and the results show that the estimated values are consistent with simulation values,especially at low longitudinal slip rate.The research can help to optimize design of non-pneumatic elastic wheel. 展开更多
关键词 driving force non-pneumatic ELASTIC WHEEL BRUSH model rolling resistance
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Forest Landscape Change and Driving Forces in Nanling National Nature Reserve,Guangdong 被引量:1
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作者 LIAO Fangjun CHEN Zhiming 《Journal of Landscape Research》 2013年第Z3期29-32,共4页
Landscape change and its driving forces are always one of the major issues in landscape ecology. In this paper,we investigated the landscape pattern of Nanling National Nature Reserve using TM data and forest stand ma... Landscape change and its driving forces are always one of the major issues in landscape ecology. In this paper,we investigated the landscape pattern of Nanling National Nature Reserve using TM data and forest stand map. The paper aims at exploring how and why the landscape changed form 1988 to 2009. The results indicated that: the major landscape types are evergreen broad-leaved forest and coniferous forests,the area ratio of both total more than 80%; area ratio of other landscape types is less than 10%,including mainly mixed coniferous and broad-leaved forest,deciduous forest,shrub,other woodland,cultivated land,other land,construction land and water. During the 20 years,evergreen broad-leaved forest landscape has become a large-scale substrate,coniferous forests are interspersed,a small area of mixed coniferous and broad-leaved mixed forest patches expands; forest area in the study area changes slightly,the number of blocks increases,the degree of landscape fragmentation increases; forest landscapes change,and are less affected by human activities,which is closely related to the establishment,management and protection of protected areas. 展开更多
关键词 FOREST landscapes driving forceS of patterns NANLING Nature RESERVE
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Forest and Agricultural Land Use Changes in the Amur River Basin in the 20th Century:Tendencies and Driving Forces
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作者 Natalia Mishina 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期135-135,共1页
The main part of the Amur River basin(over 90%) belongs to the Russian Far East and Northeastern China.Forests and agricultural lands,covering more than 70%of considered watershed,in the 20th century played a role of ... The main part of the Amur River basin(over 90%) belongs to the Russian Far East and Northeastern China.Forests and agricultural lands,covering more than 70%of considered watershed,in the 20th century played a role of important resources base for both regional economic development and growth of national economies.Present-day and future environmental conditions of adjoining regions of Russia 展开更多
关键词 Amur River basin FOREST USE AGRICULTURAL land USE driving forces
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Driving forces and their interactions of soil erosion in soil and water conservation regionalization at the county scale with a high cultivation rate
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作者 LUO Bang-lin LI Jiang-wen +2 位作者 GONG Chun-ming ZHONG Shou-qin WEI Chao-fu 《Journal of Mountain Science》 SCIE CSCD 2023年第9期2502-2518,共17页
Soil erosion control based on county scale Soil and Water Conservation Regionalization(SWCR)is an essential component of China's ecological civilization construction.In SWCR,the quantitative analysis of the spatia... Soil erosion control based on county scale Soil and Water Conservation Regionalization(SWCR)is an essential component of China's ecological civilization construction.In SWCR,the quantitative analysis of the spatial heterogeneity and driving factors of soil erosion among different regions is still lacking.It is of great significance for soil erosion control to deeply examine the factors contributing to soil erosion(natural,land use,and socioeconomic factors)and their interaction at the county and regional levels.This study focused on a highly cultivated area,Hechuan District of Chongqing in the Sichuan Basin.The district(with 30 townships)was divided into four soil and water conservation regions(Ⅰ-Ⅳ)using principal component and hierarchical cluster analysis.The driving factors of soil erosion were identified using the geographical detector model.The results showed thatⅰ)the high cultivation rate was a prominent factor of soil erosion,and the sloping farmland accounted for 78.4%of the soil erosion in the study area;ⅱ)land use factors demonstrated the highest explanatory power in soil erosion,and the average interaction of land use factors explained 60.1%of soil erosion in the study area;ⅲ)the interaction between natural factors,socioeconomic factors,and land use factors greatly contributes to regional soil erosion through nonlinear-enhancement of double-factor enhancement.This study highlights the importance of giving special attention to the effects of land use factors on soil erosion at the county scale,particularly in mountainous and hilly areas with extensive sloping farmland and a high cultivation rate. 展开更多
关键词 Soil and Water Conservation Regionalization driving factors Soil erosion Geographical detector model Spatial heterogeneity
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China's Urbanization in 1949–2015: Processes and Driving Forces 被引量:16
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作者 GU Chaolin HU Lingqian Ian G.COOK 《Chinese Geographical Science》 SCIE CSCD 2017年第6期847-859,共13页
The pace and scale of China's contemporary urbanization are stunning. This paper reviews process and the underlying driving forces of China's urbanization between 1949–2015. Contemporary China's urbanizat... The pace and scale of China's contemporary urbanization are stunning. This paper reviews process and the underlying driving forces of China's urbanization between 1949–2015. Contemporary China's urbanization has experienced four stages, and each has had different driving forces: 1) economic re-construction and industrialization-led urbanization(1949–1977); 2) economic reform and market-led urbanization(1978–1995); 3) economic globalization and the global-local urbanization(1996–2010); and 4) the land-economyled urbanization(2010–). These urbanization processes and driving forces will undoubtedly provide scientific reference and have significant implications for developing countries, especially African countries, to formulate their urbanization public policies. 展开更多
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Human Driving Forces:Analysis of Rocky Desertification in Karst Region in Guanling County,Guizhou Province 被引量:20
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作者 WU Xiuqin LIU Hongmeng +1 位作者 HUANG Xiulan ZHOU Tao 《Chinese Geographical Science》 SCIE CSCD 2011年第5期600-608,共9页
Karst rocky desertification is one of the major ecological and environmental problems that threaten the sustainable development of southwestern China. It is caused by irrational and intensive land-use patterns in kars... Karst rocky desertification is one of the major ecological and environmental problems that threaten the sustainable development of southwestern China. It is caused by irrational and intensive land-use patterns in karst geo-ecological environment. Therefore, it is vital to identify how human forces work on this degraded environment. Based on the soil erosion information in 2000 and remote sensing images of Guanling County collected in 2000 and 2007, four grades of karst rocky desertification data in 14 villages of Guanling County were extracted. Impacts of population, affluence, and other human forces on karst rocky desertification were analyzed using STIRPAT model. The results show that:1) Factors of population and affluence had strong influence on karst rocky desertification. In the STIRPAT model analysis, the population and affluence coefficients were positive, indicating that the increase in population and affluence would lead to more serious desertification. 2) Factors of farmer correlated with karst rocky desertification negatively, especially the way of viewing the relationship between people and nature, and the level of knowledge about rocky desertification. Government behavior was not a significant factor in this analysis. 3) The findings provide evidence that STIRPAT model can be used to analyze the relationship between human driving forces and rocky desertification. 展开更多
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Land-use Change and Socio-economic Driving Forces of Rural Settlement in China from 1996 to 2005 被引量:13
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作者 SONG Wei CHEN Baiming ZHANG Ying 《Chinese Geographical Science》 SCIE CSCD 2014年第5期511-524,共14页
While urbanization has accelerated, the rural population in China has started decreasing in recent years. However, the expansion of rural settlement has not been sufficiently curbed. The questions of why this has happ... While urbanization has accelerated, the rural population in China has started decreasing in recent years. However, the expansion of rural settlement has not been sufficiently curbed. The questions of why this has happened and who has driven the land-use change(LUC) of rural settlement in China have aroused great interests among researchers. In this paper, it is suggested that population is not always a positive driving force for the LUC of rural settlement in China. Furthermore, socio-economic driving forces other than urbanization, population and industrialization are analyzed. On a national scale, the major driving forces are the per-capita rural housing area and the cultivated land area. On a regional scale, the main driving forces in the eastern China are the house-building capacity of rural households and the per-capita rural housing area; while in the central China, the main driving forces are rural housing investment, the proportion of primary industry employees in the rural working population, and the cultivated land area. For the western China, the main driving forces are rural register population and cultivated land area. 展开更多
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