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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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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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Spatial-temporal Dynamics and Driving Forces of Land Development Intensity in the Western China from 2000 to 2015 被引量:17
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作者 HUANG Xin HUANG Xiaojun +2 位作者 LIU Mengmeng WANG Bo ZHAO Yonghua 《Chinese Geographical Science》 SCIE CSCD 2020年第1期16-29,共14页
The change in land development intensity is an important perspective to reflect the variation in regional social and economic development and spatial differentiation.In this paper,spatial statistical analysis,Ordinary... The change in land development intensity is an important perspective to reflect the variation in regional social and economic development and spatial differentiation.In this paper,spatial statistical analysis,Ordinary Least Squares(OLS),and Geographically weighted regression(GWR)methods are used to systematically analyse the spatial-temporal characteristics and driving forces of land development intensity for 131 spatial units in the western China from 2000 to 2015.The findings of the study are as follows:1)The land development intensity in the western China has been increasing rapidly.From 2000 to 2015,land development intensity increased by 3.4 times on average.2)The hotspot areas have shifted from central Inner Mongolia,northern Shaanxi and the Beibu Gulf of Guangxi to the Guanzhong Plain and the Chengdu-Chongqing urban agglomeration.The areas of cold spots were mainly concentrated in the Qinghai-Tibet Plateau,Yunnan,and Xinjiang.3)Investment intensity and the natural environment have always been the main drivers of land development intensity in the western China.Investment played a powerful role in promoting land development intensity,while the natural and ecological environment distinctly constrained such development.The effect of the economic factors on land development intensity in the western China has changed,which is reflected in the driving factor of construction land development shifting from economic growth in 2000 to economic structure,especially industrial structure,in 2015. 展开更多
关键词 construction land land development intensity spatial-temporal dynamic driving force the western China
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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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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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Optimization and implementation strategy of ESCO driving force in the development of energy-saving transformation market of existing buildings
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作者 GUO Han-ding DU Zhuang +1 位作者 LI Bai-tong ZHANG Yin-xian 《Ecological Economy》 2021年第4期301-314,共14页
The development of the existing building energy-saving transformation market is inseparable from the internal driving force of ESCO.Giving full play to the driving role of ESCO scientifically is the internal requireme... The development of the existing building energy-saving transformation market is inseparable from the internal driving force of ESCO.Giving full play to the driving role of ESCO scientifically is the internal requirement to promote the healthy and orderly operation of the existing building energy-saving transformation market.This paper summarizes the practical experience of developing ESCO driving force operation in foreign existing building energy-saving transformation market,analyzes the bottleneck of developing ESCO driving force operation in China’s existing building energy-saving transformation market,and puts forward useful practical enlightenment based on the comparison between home and abroad;According to the optimization principle of ESCO driving force operation in the development of existing building energy-saving transformation market,the optimization design framework of ESCO driving force is proposed,and the implementation strategy of ESCO driving force optimization in the development of existing building energy-saving transformation market is planned.In order to optimize and improve the effectiveness of the operation and development of the energy-saving transformation market of existing buildings with the internal driving force of ESCO. 展开更多
关键词 energy-saving transformation of existing buildings market development ESCO driving force optimization design implementation strategy
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Dynamic Characteristics and Driving Forces of Wetland Landscapes in Northeast China
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作者 陈静 张树文 张养贞 《Journal of Landscape Research》 2010年第12期41-47,53,共8页
Dynamic characteristics and spatial-temporal distribution patterns of wetland landscapes in northeast China from 1986 to 2000 were quantitatively analyzed and studied by applying theories and methods of landscape ecol... Dynamic characteristics and spatial-temporal distribution patterns of wetland landscapes in northeast China from 1986 to 2000 were quantitatively analyzed and studied by applying theories and methods of landscape ecology,Land Change Science,remote sensing and GIS techniques.Through analyzing the dynamic spatial-temporal change degree,direction and pattern of wetland within the study area,as well as the characteristics of landscape pattern change and landscape transformation,this study got the following results:area and patch amount of wetland in northeast China showed a decreasing trend as a whole in the past 15 years.In terms of dynamic landscape changes,although the annual decrease rate of the last 5 years was 28 times more than that of the first 10 years,the first 10 years was a period with relatively more drastic patch changes of wetland landscapes in northeast China.By reviewing the overall changes of wetland landscapes in northeast China,the following characteristics were summarized:expanding in certain periods but decreasing in the overall trend,shrinking in parts but expanding from boundaries,showing high fragmentation and so on.Study on its driving forces showed that a unique spatial pattern of wetland landscapes was formed with the dual intervention of natural and artificial factors. 展开更多
关键词 WETLAND LANDSCAPE Dynamic spatial-temporal CHANGE PATCH driving force LANDSCAPE CHANGE Science
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Spatiotemporal patterns and driving factors of soil protection in the wind-water erosion area of Chinese Loess Plateau
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作者 LI Qing LI Dan +5 位作者 WANG Sheng WANG Jinfeng WANG Rende FU Gang YUAN Yixiao ZHENG Zhenhua 《Journal of Arid Land》 SCIE CSCD 2024年第11期1522-1540,共19页
As one of typical areas in the world,northern Chinese Loess Plateau experiences serious wind-water erosion,which leads to widespread land degradation.During the past decades,an ecological engineering was implemented t... As one of typical areas in the world,northern Chinese Loess Plateau experiences serious wind-water erosion,which leads to widespread land degradation.During the past decades,an ecological engineering was implemented to reduce soil erosion and improve soil protection in this area.Thus,it is necessary to recognize the basic characteristics of soil protection for sustainable prevention and wind-water erosion control in the later stage.In this study,national wind erosion survey model and revised universal soil loss equation were used to analyze the spatiotemporal evolution and driving forces of soil protection in the wind-water erosion area of Chinese Loess Plateau during 2000–2020.Results revealed that:(1)during 2000–2020,total amount of soil protection reached up to 15.47×10^(8) t,which was realized mainly through water and soil conservation,accounting for 63.20%of the total;(2)soil protection was improved,with increases in both soil protection amount and soil retention rate.The amounts of wind erosion reduction showed a decrease trend,whereas the retention rate of wind erosion reduction showed an increase trend.Both water erosion reduction amount and retention rate showed increasing trends;and(3)the combined effects of climate change and human activities were responsible for the improvement of soil protection in the wind-water erosion area of Chinese Loess Plateau.The findings revealed the spatiotemporal patterns and driving forces of soil protection,and proposed strategies for future soil protection planning in Chinese Loess Plateau,which might provide valuable references for soil erosion control in other wind-water erosion areas of the world. 展开更多
关键词 soil protection driving force trade-off SYNERGY wind-water erosion Loess Plateau
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On the Driving Force of Regional Tourism Industry and Its Phased Evolution in China
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作者 任瀚 《Journal of Landscape Research》 2009年第3期82-85,共4页
This study aimed to discuss the phased evolution problems in driving forces of regional tourism industry in China from the perspective of temporal and spatial variation of provincial tourism destinations since reform ... This study aimed to discuss the phased evolution problems in driving forces of regional tourism industry in China from the perspective of temporal and spatial variation of provincial tourism destinations since reform and opening-up,then its own conclusion was drawn out and suggestions to sustainable development of regional tourism industry were put forward. 展开更多
关键词 TOURISM INDUSTRY driving force REGIONAL TOURISM Factor-driving
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Spatial patterns and driving forces of land use change in China during the early 21st century 被引量:170
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作者 LIU Jiyuan ZHANG Zengxiang +8 位作者 XU Xinliang KUANG Wenhui ZHOU Wancun ZHANG Shuwen LI Rendong YAN Changzhen YU Dongsheng WU Shixin JIANG Nan 《Journal of Geographical Sciences》 SCIE CSCD 2010年第4期483-494,共12页
Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of... Land use and land cover change as the core of coupled human-environment systems has become a potential field of land change science (LCS) in the study of global environmental change. Based on remotely sensed data of land use change with a spatial resolution of 1 km × 1 km on national scale among every 5 years, this paper designed a new dynamic regionalization according to the comprehensive characteristics of land use change including regional differentiation, physical, economic, and macro-policy factors as well. Spatial pattern of land use change and its driving forces were investigated in China in the early 21 st century. To sum up, land use change pattern of this period was characterized by rapid changes in the whole country. Over the agricultural zones, e.g., Huang-Huai-Hai Plain, the southeast coastal areas and Sichuan Basin, a great proportion of fine arable land were engrossed owing to considerable expansion of the built-up and residential areas, resulting in decrease of paddy land area in southern China. The development of oasis agriculture in Northwest China and the reclamation in Northeast China led to a slight increase in arable land area in northern China. Due to the "Grain for Green" policy, forest area was significantly increased in the middle and western developing regions, where the vegetation coverage was substantially enlarged, likewise. This paper argued the main driving forces as the implementation of the strategy on land use and regional development, such as policies of "Western Development", "Revitalization of Northeast", coupled with rapidly economic development during this period. 展开更多
关键词 land use change spatial pattern driving forces the early 21st century China
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Rocky Land Desertification and its Driving Forces in the Karst Areas of Rural Guangxi,Southwest China 被引量:26
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作者 LIU Yansui WANG Jieyong DENG Xiangzheng 《Journal of Mountain Science》 SCIE CSCD 2008年第4期350-357,共8页
With a subtropical climate,Guangxi Zhuang Autonomous Region has a typical karst landscape.Rocky desertification has become a serious environmental issue due to its high vulnerability caused by the joint effect of natu... With a subtropical climate,Guangxi Zhuang Autonomous Region has a typical karst landscape.Rocky desertification has become a serious environmental issue due to its high vulnerability caused by the joint effect of natural settings and human activities,because of which its eco-environment has been deteriorated in recent years,and farmland has been disappearing sharply at the same time.This,in turn,has exacerbated the poverty level in the rural areas of the region.In this study,we monitored the spatial distribution of rocky land desertification and its temporal evolution using Landsat TM/ETM images of 1985,1995,2000 and 2005.We also analyzed the driving forces of the desertification and its expansion.Through constructing regression models by using all the relevant variables and considering the lagged effects as well as fixed effects,we quantified the exact role of different factors causing rocky land desertification in the study area with some new findings.The new findings in this study are greatly helpful for preserving,restoring and reconstructing the degraded mountain environment in Guangxi and other karst areas in Southwest China,and also for alleviating poverty in the rural areas in the future. 展开更多
关键词 Rocky land desertification karstmountain area rural poverty driving force GUANGXI Southwest China
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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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STUDY ON THE SPATIAL PATTERNS OF LAND-USE CHANGE AND ANALYSES OF DRIVING FORCES IN NORTHEASTERN CHINA DURING 1990-2000 被引量:11
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作者 LIUJi-yuan DENGXiang-zheng +1 位作者 LIUMing-liang ZHANGShu-wen 《Chinese Geographical Science》 SCIE CSCD 2002年第4期299-308,共10页
Land-use change is an important aspect of global environment change. It is,in a sense, the direct result of human activities influencing our physical environment. Supported bythe dynamic serving system of national res... Land-use change is an important aspect of global environment change. It is,in a sense, the direct result of human activities influencing our physical environment. Supported bythe dynamic serving system of national resources, including both the environment database and GIStechnology, this paper analyzed the land-use change in northeastern China in the past ten years(1990 ― 2000). It divides northeastern China into five land-use zones based on the dynamic degree(DD) of land-use: woodland/grassland ― arable land conversion zone, dry land ― paddy fieldconversion zone, urban expansion zone, interlocked zone of farming and pasturing, and reclamationand abandoned zone. In the past ten years, land-use change of northeastern China can be generalizedas follows: increase of cropland area was obvious, paddy field and dry land increased by 74. 9 and276. 0 thousand ha respectively; urban area expanded rapidly, area of town and rural residenceincreased by 76. 8 thousand ha; area of forest and grassland decreased sharply with the amount of1399. 0 and 1521. 3 thousand ha respectively; area of water body and unused land increased by 148. 4and 513. 9 thousand ha respectively. Besides a comprehensive analysis of the spatial patterns ofland use, this paper also discusses the driving forces in each land-use dynamic zones. The studyshows that some key biophysical factors affect conspicuously the conversion of different land-usetypes. In this paper, the relationships between land-use conversion and DEM, accumulated temperature(≥10℃) and precipitation were analysed and represented. We conclude that the land-use changes innortheast China resulted from the change of macro social and economic factors and local physicalelements. Rapid population growth and management changes, in some sense, can explain the shaping ofwoodland/grassland ― cropland conversion zone. The conversion from dry land to paddy field in thedry land ― paddy field conversion zone, apart from the physical elements change promoting theexpansion of paddy field, results from two reasons: one is that the implementation of market-economyin China has given fanners the right to decide what they plant and how they plant their crops, theother factor is originated partially from the change of dietary habit with the social and economicdevelopment. The conversion from paddy field to dry land is caused primarily by the shortfall ofirrigation water, which in turn is caused by poor water allocation managed by local governments. Theshaping of the reclamation and abandoned zone is partially due to the lack of environmentprotection consciousness among pioneer settlers. The reason for the conversion from grassland tocropland is the relatively higher profits of farming than that of pasturing in the interlocked zoneof farming and pasturing. In northeastern China, the rapid expansion of built-up areas results fromtwo factors: the first is its small number of towns; the second comes from the huge potential forexpansion of existing towns and cities. It is noticeable that urban expansion in the northeasternChina is characterized by gentle topographic relief and low population density. Physiognomy,transportation and economy exert great influences on the urban expansion. 展开更多
关键词 land use land-use change spatial pattern driving force northeasternchina
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Landscape pattern change and driving force of blowout distribution in the Hulun Buir Sandy Grassland 被引量:6
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作者 Eerdun Hasi 《Research in Cold and Arid Regions》 2012年第5期431-438,共8页
The land coverage pattern changes for the past 50 years in a typical region of the Hulun Buir Sandy Grassland were interpreted and analyzed based on a series of remote sensing images in 1959, 2002, 2004 and 2009. The ... The land coverage pattern changes for the past 50 years in a typical region of the Hulun Buir Sandy Grassland were interpreted and analyzed based on a series of remote sensing images in 1959, 2002, 2004 and 2009. The temporal and spatial changes of landscape patterns were revealed and the driving forces were analyzed. The results show that all land coverage types had large variable amplitudes. The grassland area decreased, whereas other areas incleased. Owing to implementation of artificial sand fixation from 2004 to 2009, the areas of flowing blowouts and depositional area decreased by 71,369 and 128,835 m2, respectively. The average patch area reduced, but the number of blowouts increased, fractal dimension increased, and blowout structure became complex. The fragmentation index increased, whereas contagion index decreased. Driving force analysis shows that human factors such as overglazing are slightly larger than natural factors of increased temperature and decreased precipitation 展开更多
关键词 BLOWOUT landscape pattems Hukm Buir driving force
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Long-term Dynamics of Cultivated Land Resources and Their Driving Forces of Guyuan City in Upper Reaches of Jinghe River 被引量:3
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作者 CHEN Caocao XIE Gaodi +1 位作者 ZHEN Lin LENG Yunfa 《Chinese Geographical Science》 SCIE CSCD 2008年第1期33-40,共8页
The land use patterns in Guyuan City,Ningxia Hui Autonomous Region of China,have changed greatly over the years,due to population growth and farming and stock raising development.This study,using 50-year statis-tical ... The land use patterns in Guyuan City,Ningxia Hui Autonomous Region of China,have changed greatly over the years,due to population growth and farming and stock raising development.This study,using 50-year statis-tical data of cultivated land and 14-year spatial data of land use pattern,analyzed the developmental stages,the char-acter,and the spatial variance of farmland in the city,and discussed the driving forces of cultivated land changes based on empirical and conceptual statistical models.First,the change of cultivated land area went through different stages of rapid increase,fluctuating change,decrease and rapid decrease from 1949 to 2004,additionally,social and economic policies in different stages had an important impact on farmland variance.Second,from 1986 to 2000,the quantity of cultivated land increased,but its quality decreased.Third,social and economic factors are determinant factors in culti-vated land transition.Five constructed paths explain cultivated land transition.Factors that have direct or indirect ef-fects on farmland include the economy(Xeco),the population(Xpop),agricultural output(Xagr),and scientific input(Xsci).The sequence of impact was Xeco>Xpop>Xsci>Xagr.Among all these impacts,Xeco was the major positive one,and Xpop was the major negative one.It is urgent to take measures or adopt a policy to stop the vicious cycle in eco-environment and agriculture production.Otherwise,negative patterns of farmland use will increase,and high-quality cultivated land will continue to decline. 展开更多
关键词 cultivated land transition driving forces national policy economic development POPULATION scientific input
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Driving Force and Ecosystem Service Values Estimation in the Extreme Arid Region from 1975 to 2015:A Case Study of Alxa League,China 被引量:5
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作者 XIE Jiali LU Zhixiang +1 位作者 XIAO Shengchun YAN Changzhen 《Chinese Geographical Science》 SCIE CSCD 2021年第6期1097-1107,共11页
The research on ecosystem service values(ESVs)estimation in arid region is weak.We took the Alxa League of China’s Inner Mongolia Autonomous Region,an extreme arid region,as an example and constructed an equivalent c... The research on ecosystem service values(ESVs)estimation in arid region is weak.We took the Alxa League of China’s Inner Mongolia Autonomous Region,an extreme arid region,as an example and constructed an equivalent coefficient method to assess its ESVs from 1975 to 2015,by determining the standard unit of ESVs and the basic equivalent of the value of different ecosystem services per unit area based on the regional characteristics,literature research,expert knowledge and land use data.The results show that the ESVs first decreased from 83170.4 million yuan(RMB)in 1975 to 82337.8 million yuan(RMB)in 2000 and then increased to84033.6 million yuan(RMB)in 2015,and the ESV of sparse grassland and desert account for about 33%and 29%of the total ESVs,respectively.Among the four service types,the regulating services,support services,supply services and cultural services account for66.5%,22.8%,6.0%and 4.7%,respectively.The changes of ESVs in Alxa League are determined by the socio-economic development and ecological changes.This study provides a new method to estimate the ESVs in arid region by integrating existing methods and regional characteristics,such as the cost of water for arid ecosystems. 展开更多
关键词 ecosystem service values equivalent coefficient method driving force arid region Alxa League China
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Improved plane layout of stabilizing piles based on the piecewise function expression of the irregular driving force 被引量:3
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作者 LIU Wen-qiang LI Qun +3 位作者 LU Jian LI Chang-dong YAO Wen-min ZENG Jiang-bo 《Journal of Mountain Science》 SCIE CSCD 2018年第4期871-881,共11页
The paper presents an improved plane layout for stabilizing piles based on a proposed piecewise function expression for the irregular driving force. Based on the specific morphological characteristics of a highway lan... The paper presents an improved plane layout for stabilizing piles based on a proposed piecewise function expression for the irregular driving force. Based on the specific morphological characteristics of a highway landslide, the piecewise function is used to calculate the irregular driving force by dividing the landslide into several sub-areas.Furthermore, the reasonable layout range and pile spacing can be obtained based on the piecewise function expression of the irregular driving force and on relevant research results of the plane layout for stabilizing piles. Therefore, an improved plane layout of stabilizing piles is presented in consideration of a piecewise function expression of the irregular driving force. A highway landslide located in eastern Guizhou Province, China, is analyzed as a case study using the proposed method. The results demonstrate that the theory presented in this paper provides improved economic benefits and can reduce the requirednumber of stabilizing piles by 28.6% compared with the conventional plane layout scheme. 展开更多
关键词 Highway landslide driving force Piecewise function Stabilizing pile Plane layout
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Application of a new wind driving force model in soil wind erosion area of northern China 被引量:2
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作者 ZOU Xueyong LI Huiru +5 位作者 LIU Wei WANG Jingpu CHENG Hong WU Xiaoxu ZHANG Chunlai KANG Liqiang 《Journal of Arid Land》 SCIE CSCD 2020年第3期423-435,共13页
The shear stress generated by the wind on the land surface is the driving force that results in the wind erosion of the soil.It is an independent factor influencing soil wind erosion.The factors related to wind erosiv... The shear stress generated by the wind on the land surface is the driving force that results in the wind erosion of the soil.It is an independent factor influencing soil wind erosion.The factors related to wind erosivity,known as submodels,mainly include the weather factor(WF)in revised wind erosion equation(RWEQ),the erosion submodel(ES)in wind erosion prediction system(WEPS),as well as the drift potential(DP)in wind energy environmental assessment.However,the essential factors of WF and ES contain wind,soil characteristics and surface coverings,which therefore results in the interdependence between WF or ES and other factors(e.g.,soil erodible factor)in soil erosion models.Considering that DP is a relative indicator of the wind energy environment and does not have the value of expressing wind to induce shear stress on the surface.Therefore,a new factor is needed to express accurately wind erosivity.Based on the theoretical basis that the soil loss by wind erosion(Q)is proportional to the shear stress of the wind on the soil surface,a new model of wind driving force(WDF)was established,which expresses the potential capacity of wind to drive soil mass in per unit area and a period of time.Through the calculations in the typical area,the WDF,WF and DP are compared and analyzed from the theoretical basis,construction goal,problem-solving ability and typical area application;the spatial distribution of soil wind erosion intensity was concurrently compared with the spatial distributions of the WDF,WF and DP values in the typical area.The results indicate that the WDF is better to reflect the potential capacity of wind erosivity than WF and DP,and that the WDF model is a good model with universal applicability and can be logically incorporated into the soil wind erosion models. 展开更多
关键词 soil wind erosion wind driving force weather factor drift potential WDF(wind driving force)model
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A Study of the Driving Force for Inclusion Complexation of α- and β- Cyclodextrin with Substituted Benzene 被引量:1
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作者 ZHANG Hai-ming LUO Shuang-hui +3 位作者 CHEN Chao LIU Lei GUO Qing-xiang LIU You-cheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1999年第1期19-24,共6页
The driving force for inclusion complexation of α and β CD with substituted benzene(PhX) was studied by means of step wise regression analysis. A set of multiple regression equations was established with... The driving force for inclusion complexation of α and β CD with substituted benzene(PhX) was studied by means of step wise regression analysis. A set of multiple regression equations was established with correlation coefficients 0 96 and 0 94 for the individual complexation of α CD and β CD with PhX. The ln K a(calc.) values calculated with the aid of the regression equations were close to those determined experimentally. The inclusion complexation is dominantly driven by van der Waals force and hydrophobic interactions. 展开更多
关键词 CYCLODEXTRIN driving force INCLUSION Regression Substituted benzene
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On the Development of an Effective Pressure Driving System for Ultra-Low Permeability Reservoirs 被引量:4
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作者 Yapu Zhang Zhengming Yang +2 位作者 Dajian Li Xuewei Liu Xinli Zhao 《Fluid Dynamics & Materials Processing》 EI 2021年第6期1067-1075,共9页
Given its relevance to the exploitation of ultra-low permeability reservoirs,which account for a substantial proportion of the world’s exploited and still unexploited reserves,in the present study the development of ... Given its relevance to the exploitation of ultra-low permeability reservoirs,which account for a substantial proportion of the world’s exploited and still unexploited reserves,in the present study the development of an adequate water injection system is considered.Due to the poor properties and weak seepage capacity of these reservoirs,the water injection pressure typically increases continuously during water flooding.In this research,the impact on such a process of factors as permeability,row spacing,and pressure gradient is evaluated experimentally using a high-pressure large-scale outcrop model.On this basis,a comprehensive evaluation coefficient is introduced able to account for the effective driving pressure. 展开更多
关键词 Ultra-low permeability reservoir physical simulation effective development water flooding effective driving coefficient
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