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Inequality and the Urban-rural Divide in China:Effects of Regressive Taxation 被引量:10
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作者 Jenifer Piesse 《China & World Economy》 SCIE 2010年第6期36-55,共20页
Using three comparable national representative household surveys for China in 1988, 1995 and 2002, the present paper reveals the regressivity and urban bias of China's direct tax and welfare system in this period It ... Using three comparable national representative household surveys for China in 1988, 1995 and 2002, the present paper reveals the regressivity and urban bias of China's direct tax and welfare system in this period It shows that a regressive taxation system and skewed allocation of subsidies increases the urban-rural income gap and enhances overall inequality. Modeling these relationships indicates that the relatively poorer rural population has a net tax liability, whereas those in the richer urban areas receive net subsidies. This pattern is common in China, although the extent of the bias varies. This skewed system of tax and welfare payments is a major cause of the persisting urban-rural income gap and contributes to the overall income inequality in China. The abolishment of the agriculture tax in 2006 has had a positive impact on rural people 's livelihoods. 展开更多
关键词 China INEQUALITY SUBSIDIES TAXATION urban-rural divide
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Mapping and measuring urban-rural inequalities in accessibility to social infrastructures
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作者 Chenmeng Guo Weiqi Zhou +1 位作者 Chuanbao Jing Dawa Zhaxi 《Geography and Sustainability》 CSCD 2024年第1期41-51,共11页
Equal access to social infrastructures is a fundamental prerequisite for sustainable development,but has long been a great challenge worldwide.Previous studies have primarily focused on the accessibility to social inf... Equal access to social infrastructures is a fundamental prerequisite for sustainable development,but has long been a great challenge worldwide.Previous studies have primarily focused on the accessibility to social infras-tructures in urban areas across various scales,with less attention to rural areas,where inequality can be more severe.Particularly,few have investigated the disparities of accessibility to social infrastructures between urban and rural areas.Here,using the Changsha-Zhuzhou-Xiangtan urban agglomeration,China,as an example,we investigated the inequality of accessibility in both urban and rural areas,and further compared the urban-rural difference.Accessibility was measured by travel time of residents to infrastructures.We selected four types of social infrastructures including supermarkets,bus stops,primary schools,and health care,which were funda-mentally important to both urban and rural residents.We found large disparities in accessibility between urban and rural areas,ranging from 20 min to 2 h.Rural residents had to spend one to two more hours to bus stops than urban residents,and 20 min more to the other three types of infrastructures.Furthermore,accessibility to multiple infrastructures showed greater urban-rural differences.Rural residents in more than half of the towns had no access to any infrastructure within 15 min,while more than 60%of the urban residents could access to all infrastructures within 15 min.Our results revealed quantitative accessibility gap between urban and rural areas and underscored the necessity of social infrastructures planning to address such disparities. 展开更多
关键词 ACCESSIBILITY Social infrastructures urban-rural difference INEQUALITY Regional sustainability
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Spatial Distribution Pattern and Influencing Factors of Bed-and-breakfasts(B&Bs)from the Perspective of Urban-rural Differences:A Case Study of Jiaodong Peninsula,China
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作者 WANG Xinyue MA Qian 《Chinese Geographical Science》 SCIE CSCD 2024年第4期752-763,共12页
There are significant differences between urban and rural bed-and-breakfasts(B&Bs)in terms of customer positioning,economic strength and spatial carrier.Accurately identifying the differences in spatial characteri... There are significant differences between urban and rural bed-and-breakfasts(B&Bs)in terms of customer positioning,economic strength and spatial carrier.Accurately identifying the differences in spatial characteristics and influencing factors of each type,is essential for creating urban and rural B&B agglomeration areas.This study used density-based spatial clustering of applications with noise(DBSCAN)and the multi-scale geographically weighted regression(MGWR)model to explore similarities and differences in the spatial distribution patterns and influencing factors for urban and rural B&Bs on the Jiaodong Peninsula of China from 2010 to 2022.The results showed that:1)both urban and rural B&Bs in Jiaodong Peninsula went through three stages:a slow start from 2010 to 2015,rapid development from 2015 to 2019,and hindered development from 2019 to 2022.However,urban B&Bs demonstrated a higher development speed and agglomeration intensity,leading to an increasingly evident trend of uneven development between the two sectors.2)The clustering scale of both urban and rural B&Bs continued to expand in terms of quantity and volume.Urban B&B clusters characterized by a limited number,but a higher likelihood of transitioning from low-level to high-level clusters.While the number of rural B&B clusters steadily increased over time,their clustering scale was comparatively lower than that of urban B&Bs,and they lacked the presence of high-level clustering.3)In terms of development direction,urban B&B clusters exhibited a relatively stable pattern and evolved into high-level clustering centers within the main urban areas.Conversely,rural B&Bs exhibited a more pronounced spatial diffusion effect,with clusters showing a trend of multi-center development along the coastline.4)Transport emerged as a common influencing factor for both urban and rural B&Bs,with the density of road network having the strongest explanatory power for their spatial distribution.In terms of differences,population agglomeration had a positive impact on the distribution of urban B&Bs and a negative effect on the distribution of rural B&Bs.Rural B&Bs clustering was more influenced by tourism resources compared with urban B&Bs,but increasing tourist stay duration remains an urgent issue to be addressed.The findings of this study could provide a more precise basis for government planning and management of urban and rural B&B agglomeration areas. 展开更多
关键词 urban-rural bed-and-breakfasts(B&Bs) spatiotemporal evolution density-based spatial clustering of applications with noise(DBSCAN)model multi-scale geographically weighted regression(MGWR) Jiaodong Peninsula China
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Analysis of Mobile and Internet Network Coverage: Propagation of Electromagnetic Waves and Concept of Digital Divide in Burundi
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作者 Apollinaire Bigirimana Jérémie Ndikumagenge +2 位作者 Sami Tabbane Romeo Nibitanga Hassan Kibeya 《Open Journal of Antennas and Propagation》 2024年第1期1-18,共18页
Mobile and Internet network coverage plays an important role in digital transformation and the exploitation of new services. The evolution of mobile networks from the first generation (1G) to the 5th generation is sti... Mobile and Internet network coverage plays an important role in digital transformation and the exploitation of new services. The evolution of mobile networks from the first generation (1G) to the 5th generation is still a long process. 2G networks have developed the messaging service, which complements the already operational voice service. 2G technology has rapidly progressed to the third generation (3G), incorporating multimedia data transmission techniques. It then progressed to fourth generation (4G) and LTE (Long Term Evolution), increasing the transmission speed to improve 3G. Currently, developed countries have already moved to 5G. In developing countries, including Burundi, a member of the East African Community (ECA) where more than 80% are connected to 2G technologies, 40% are connected to the 3G network and 25% to the 4G network and are not yet connected to the 5G network and then still a process. The objective of this article is to analyze the coverage of 2G, 3G and 4G networks in Burundi. This analysis will make it possible to identify possible deficits in order to reduce the digital divide between connected urban areas and remote rural areas. Furthermore, this analysis will draw the attention of decision-makers to the need to deploy networks and coverage to allow the population to access mobile and Internet services and thus enable the digitalization of the population. Finally, this article shows the level of coverage, the digital divide and an overview of the deployment of base stations (BTS) throughout the country to promote the transformation and digital inclusion of services. 展开更多
关键词 Coverage of Mobile Networks and Internet Digital divide Rural and Isolated Areas Antenna Connectivity and Digital Inclusion
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Spatial pattern of urban-rural integration in China and the impact of geography 被引量:1
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作者 Wei Pan Jing Wang +2 位作者 Yurui Li Shuting Chen Zhi Lu 《Geography and Sustainability》 CSCD 2023年第4期404-413,共10页
Urban-rural integration (URI) is a global challenge that is highly related to inequalities, poverty, economic growth, and other Sustainable Development Goals (SDGs). Existing research has evaluated the extent of URI a... Urban-rural integration (URI) is a global challenge that is highly related to inequalities, poverty, economic growth, and other Sustainable Development Goals (SDGs). Existing research has evaluated the extent of URI and explored its influencing factors, but urban-rural linkages are seldom incorporated in evaluation systems, and geographical factors are rarely recognized as the influencing factors. We construct a URI framework including regional economy, rural development, urban-rural linkage, and urban-rural gap. Based on a dataset consisting of 1,669 counties in China in 2020, we reveal the spatial pattern of URI and find a high correlation between the spatial pattern of URI and the relief degree of land surface (RDLS). Using structural equation modeling, we discover that topography has direct ( − 0.18, p < 0.001) and indirect ( − 0.17, p < 0.001) effects on URI. The indirect negative effects are mediated through the infrastructure, and the combination of localized advantages and modern technical conditions could mitigate the negative impact of topography. Finally, we identify 742 counties as lagging regions in URI, which can be clustered into eight types. Our findings could facilitate policy designing for those countries striving for integrated and sustainable development of urban and rural areas. 展开更多
关键词 urban-rural integration Relief degree of land surface INFRASTRUCTURE Structural equation modelling Sustainable urban and rural development PATTERNS Sustainable Development Goals
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Spatiotemporal Evolution and Influencing Factors of Urban-rural Construction Land in Rural Industrialized Areas in China:Case Studies in Changyuan City and Xinxiang County of Henan Province
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作者 SHI Yanwen LI Xiaojian +1 位作者 HU Xueyao LI Zeyi 《Chinese Geographical Science》 SCIE CSCD 2023年第5期850-864,共15页
Since China’s reform and opening up in 1978,the acceleration of industrialization and urbanization in China had led to dramatic changes in the pattern of urban-rural land use.In this paper,we focused on the rural ind... Since China’s reform and opening up in 1978,the acceleration of industrialization and urbanization in China had led to dramatic changes in the pattern of urban-rural land use.In this paper,we focused on the rural industrialized areas in central China(Xinxiang County and Changyuan City of Henan Province).We used the average nearest neighbor index,spatial statistical analysis,and a structural equation model to analyze the spatiotemporal evolution and influencing factors of urban-rural construction land based on multisource spatial data and survey data.The results showed that:1)from 1975 to 2019,the spatial distribution of urban-rural construction land in rural industrialized areas had evolved from homogeneous distribution to local agglomeration.In terms of comparative analysis of cases,the spatial distribution of urban-rural construction land in Changyuan City had shown a trend from diffusion to agglomeration,and Xinxiang County had overall shown a spatial change from homogenization to agglomeration and then to regional integration development.2)The hot spots with increased urban-rural construction land significantly expanded,and they had a high degree of spatial overlap with industrial development.Among them,Xinxiang County was concentrated in central and marginal areas,and Changyuan was mainly concentrated in central urban areas.3)From the evolution of spatial proximity of urban-rural construction land,rural industrialized areas generally decline,showing the characteristics of internal differentiation in the rate of change.4)Industrial development,social economy,the policy environment,and urban development played a positive role in promoting the expansion of urban-rural construction land in rural industrialized areas.To promote the optimal use of regional land and the integrated development of urban-rural areas,we should combine the advantages of regional endowment,formulate development strategies according to local conditions,and adjust the way that land is used in a timely manner. 展开更多
关键词 urban-rural construction land rural industrialized areas spatiotemporal evolution influencing factors rural industrialization Henan Province China
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A new approach towards the sustainability of urban-rural integration:The development strategy for central villages in the Abbasiya District of Iraq using GIS techniques
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作者 Ahmed Hussein ALLAWI Haider Mohammed Jawad AL-JAZAERI 《Regional Sustainability》 2023年第1期28-43,共16页
The development of rural areas usually has a positive impact on the urban-rural integration. This study explores an innovative approach to stimulate rural development by proposing qualified villages as central village... The development of rural areas usually has a positive impact on the urban-rural integration. This study explores an innovative approach to stimulate rural development by proposing qualified villages as central villages that can provide basic urban services for their residents and residents of neighboring villages. This approach can contribute to overcoming the various problems that rural areas faced at the social, economic, and environmental levels. It seeks to achieve spatial sustainability of rural areas, representing a new approach by integrating urban development methods to revitalize rural villages. The study analyzed 15 villages belonging to Abbasiya District of AL Kufa City in the Najaf Governorate of Iraq. Based on the GIS techniques and the analysis of urban service indicators(village population, percentage of urban building materials used in villages, distance between village and health centers, distance between village and main roads, nature of economic activity, distance between village and educational institutions, distance between village and drinking water sources, number of communication towers, and distance between village and urban administrative center), this study proposed that Abu Gharb and Albu Ghraib can served as central villages in Abbasiya District in the future. This study establishes a new rural spatial structure to achieve rural sustainable development, improves the development status of rural areas, and provides a theoretical basis for the government and relevant institutions to use urban service indicators, achieving rural sustainable development and formulating relevant development policies in Abbasiya District. 展开更多
关键词 Central villages Spatial reorganization Rural sustainable development urban-rural integration Urban service Abbasiya District Iraq
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The Formation Logic of the Digital Divide and Feasible Ways to Cross It:An Access-Based Analysis
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作者 Xu Haixin Yang Chen Yang Chanchan 《Contemporary Social Sciences》 2023年第3期29-42,共14页
How enterprises overcome the digital divide in a digital economy is a topic related to efficiency and fairness.The formation of the digital divide has showcased a certain level of objectivity and is also influenced by... How enterprises overcome the digital divide in a digital economy is a topic related to efficiency and fairness.The formation of the digital divide has showcased a certain level of objectivity and is also influenced by the characteristics of enterprises themselves.Based on the model that expands the information and communication technology(ICT)access,concept,we explored the digital divide’s formation logic of the digital divide and feasible ways to cross it.Our findings shed light on its formation logic,which includes elements of the subjective will of enterprises to transform,the fear of transformation,the dependence on development paths,and the cost of using digital technology,all of which have contributed to disparities in enterprises’motivational access.In addition,differences in the construction of digital infrastructure,financial strengths,business models,and heterogeneity in cluster networks have led to differences in enterprises’material access.The absorptive capacity of enterprises has affected their skill access,while the management capability influences the application access of enterprises.We also found that crossing the digital divide requires the joint efforts of governments,markets,and enterprises in the four access dimensions. 展开更多
关键词 digital divide ICT access digital technology motivational access skill access
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Thinking about Value Realization of Ecological Products under the Background of Urban-rural Integration in Chengdu“Western Control”Area
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作者 ZHANG Xuequan ZHANG Yi 《Journal of Landscape Research》 2023年第2期59-62,共4页
Chengdu's development strategy of“western control”has laid a solid ecological background for 8 western districts,cities and counties and cultivated good ecological resources.The integrated urban-rural developmen... Chengdu's development strategy of“western control”has laid a solid ecological background for 8 western districts,cities and counties and cultivated good ecological resources.The integrated urban-rural development in the new era will realize the balanced development of urban and rural areas and give full play to the value of rural ecological resources through the“powerful combination”of urban and rural areas.To realize the urban-rural integration and high-quality rural development in Chengdu“western control”area,it is necessary to enhance the awareness of ecological resources and ecological products,and carry out unified planning of ecological infrastructure,ecological material products and ecological service products in the whole“western control”area.Meantime,ecological restoration must be carried out scientifically,and scene design for value transformation of ecological products should be implemented innovatively. 展开更多
关键词 Western control urban-rural integration Ecological products Ecological value transformation
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Optimization of DC Resistance Divider Up to 1200 kV Using Thermal and Electric Field Analysis
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作者 Dengyun Li Baiwen Du +3 位作者 Kai Zhu Jicheng Yu Siyuan Liang Changxi Yue 《Energy Engineering》 EI 2023年第11期2611-2628,共18页
Self-heating and electric field distribution are the primary factors affecting the accuracy of the Ultra High Voltage Direct Current(UHVDC)resistive divider.Reducing the internal temperature rise of the voltage divide... Self-heating and electric field distribution are the primary factors affecting the accuracy of the Ultra High Voltage Direct Current(UHVDC)resistive divider.Reducing the internal temperature rise of the voltage divider caused by self-heating,reducing the maximum electric field strength of the voltage divider,and uniform electric field distribution can effectively improve the UHVDC resistive divider’s accuracy.In this paper,thermal analysis and electric field distribution optimization design of 1200 kV UHVDC resistive divider are carried out:(1)Using the proposed iterative algorithm,the heat dissipation and temperature distribution of the high voltage DC resistive divider are studied,and the influence of the ambient temperature and the power of the divider on the temperature of the insulating medium of the divider is analyzed;(2)Established the finite element models of 1200 kV and 2×600 kV DC resistive dividers,analyzed the influence of the size of the grading ring and the installation position on the maximum electric field strength of the voltage divider,and calculated the impact of the shielding resistor layer on the vicinity of the measuring resistor layer.The research indicates that:(1)The temperature of the insulating medium is linearly related to the horsepower of the voltage divider and the ambient temperature;(2)After the optimized design of the electric field,the maximum electric field strength of the 1200 kV DC resistive divider is reduced to 1471 V/mm,which is about 24% lower than that of the unoptimized design;(3)Installing the shielding resistor layer can significantly improve the electric field near the measuring resistor layer.This paper has an important reference function for improving the accuracy of the UHVDC resistive divider. 展开更多
关键词 DC voltage divider heat transfer electric field grading ring shielding resistor layer optimized design
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A Miniaturized Broadband Wilkinson Power Divider Using Micro-Strip Branch Lines
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作者 Taifu Zhou 《Journal of Computer and Communications》 2023年第12期102-108,共7页
A miniaturized broadband Wilkinson power divider is proposed. Micro-strip branch lines are introduced to replace multiple resistors used in multi-stage Wilkinson power dividers to increase the bandwidth of single-stag... A miniaturized broadband Wilkinson power divider is proposed. Micro-strip branch lines are introduced to replace multiple resistors used in multi-stage Wilkinson power dividers to increase the bandwidth of single-stage Wilkinson power dividers. To demonstrate its performance, an improved single-stage Wilkinson power divider with four micro-strip branch lines was designed. Simulated results show that the insert loss is better than 3.2 dB, the input return loss, output return loss, and isolation are better than 15 dB respectively, across a 76% bandwidth from 18 to 40 GHz. . 展开更多
关键词 BROADBAND Micro-Strip Branch Lines Power divider
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Innovation in the Public Sector in the Start-up Nation:Challenges of Technology,Bureaucracy,and Digital Divide
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作者 Yaron Katz 《Journalism and Mass Communication》 2023年第2期51-59,共9页
Innovation provides opportunities to all countries,as advancement in technology and globalization of economic markets encourage global competition and increase the role of governments in gaining a strategic competitiv... Innovation provides opportunities to all countries,as advancement in technology and globalization of economic markets encourage global competition and increase the role of governments in gaining a strategic competitive advantage while boosting economic growth and productivity.According to the OECD,innovation can make a difference in addressing developmental challenges and providing catalyst for countries to accelerate business processes and practices that improve public service efficiency.The public sector plays a significant role in modern economies and innovation is a necessary condition for improving government services to the public and creating a competitive economy.Israel is known as the“start-up nation”,but innovation policies and strategies relating to the public sector are less developed than those of business innovation due to lack of innovation culture,digital divide,and bureaucracy.The research examines innovation in the public sector in Israel compared to other OECD countries.It is argued that despite the enormous influence of high-tech and start-ups on the economy and gross of national product,the flourishing technology sector has not contributed to other sectors of the economy and the performance of the public service lags behind the private sector in terms of innovation and efficiency.The research concludes that implementing Israel’s success in business innovation into the public sector requires long-run strategic investments and public policies to increase the supply and quality of human capital and infrastructure.The goal should be to narrow digital divide with other developed countries and advance the technological capabilities and productivity of the public service. 展开更多
关键词 INNOVATION TECHNOLOGY BUREAUCRACY digital divide Israel
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Outlier-DivideConquer:近似聚集查询中离群分治取样算法 被引量:1
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作者 胡文瑜 孙志挥 张柏礼 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第5期524-531,共8页
取样是一种通用有效的近似技术,利用取样技术进行近似聚集查询处理是决策支持系统和数据挖掘实现技术中的常用方法.如何正确有效地给出近似查询结果并最小化近似查询误差是近似查询处理的关键和目标.在深入研究近似聚集查询取样方法的... 取样是一种通用有效的近似技术,利用取样技术进行近似聚集查询处理是决策支持系统和数据挖掘实现技术中的常用方法.如何正确有效地给出近似查询结果并最小化近似查询误差是近似查询处理的关键和目标.在深入研究近似聚集查询取样方法的基础上,本文提出了一个有误差确界且只需单遍扫描数据集的离群分治取样Outlier-DivideConquer算法,该算法在聚集属性内部存在高方差分布时能克服随机均匀取样局限,可显著降低近似查询误差,且执行效率优于同类算法.最后通过与传统均匀取样算法的实验比较验证了Outlier-DivideConquer算法的有效性和正确性. 展开更多
关键词 数据挖掘 决策支持 近似聚集查询 均匀取样 离群分治
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Bridging Digital Divide for English Learners at Chinese Secondary Schools
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作者 曾爽 郑瑞珺 《海外英语》 2021年第8期263-264,共2页
This article reviews the concept of digital divide and particularly discusses the digital divide among K-12 students in rural and urban China,as well as the e-learning strategies initiated by the Chinese government th... This article reviews the concept of digital divide and particularly discusses the digital divide among K-12 students in rural and urban China,as well as the e-learning strategies initiated by the Chinese government that were designed to minimize this digital divide in China.This article concludes by explaining the issue of skills on effective e-learning and correspondingly making suggestions for English teachers in K-12 schools in China. 展开更多
关键词 Digital divide e-learning strategies K-12 school English teaching
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AN OVERVIEW ON THE URBAN-RURAL INTERACTION IN THE PAST 50 YEARS IN CHINA 被引量:4
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作者 Qi Lu Jin-yan Zhan Kang-won Lee 《Chinese Geographical Science》 SCIE CSCD 2001年第3期2-9,共8页
China is a country with a long history of agricultural development,the tr adition of bureaucratic administra-tion and economic management system s for the social development.In its t ransition from traditional society... China is a country with a long history of agricultural development,the tr adition of bureaucratic administra-tion and economic management system s for the social development.In its t ransition from traditional society to modern soci-ety during the past 50years,the rela tions between rural areas and urban a reas have been kept abnormal if considered from the point of view of the modernized co untries.Today,China still has its more than 70percent of population,bu t limited capital,lower technology and underdeveloped culture,in the rural areas.This unbalance forms not only the o bstacles to China’s modernization of social development,but also the barriers to th e society,economy and environment sustainable devel-opment.This paper focuses on the dis cussion about the coordinate develo pment of the relations between rural and urban in the past 50years,and the authors hold that only has the abnormal relation between the two areas been corrected,could China’s future development of natio nal economy be successful. 展开更多
关键词 urban-rural interaction coordin ATE DEVELOPMENT of urban-rural RELA tion DEVELOPMENT of national econo-my
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The Art of Power Dividing:A Review for State-of-the-Art Planar Power Dividers 被引量:4
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作者 Yongle Wu Lingxiao Jiao +1 位作者 Zheng Zhuang Yuanan Liu 《China Communications》 SCIE CSCD 2017年第5期1-16,共16页
In this paper,massive state-of-theart planar power dividers are presented and discussed. The innovations of these superiorly-performanced power dividers lie in the performance breakthrough,physical configurations and ... In this paper,massive state-of-theart planar power dividers are presented and discussed. The innovations of these superiorly-performanced power dividers lie in the performance breakthrough,physical configurations and function integrations. Eventually,based on the trend presented,the future of the power dividers is predicted. This paper might have inspiration significance to illuminate the way for the development of power dividers. 展开更多
关键词 power divider microwave circuit microwave passive component analog circuit
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Use of Topographic Map Evidence to Test a Recently Proposed Regional Geomorphology Paradigm: Wind River-Sweetwater River Drainage Divide Area, Central Wyoming, USA 被引量:4
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作者 Eric Clausen 《Open Journal of Geology》 2019年第8期404-423,共20页
Topographic map evidence from the Wyoming Wind River-Sweetwater River drainage divide area is used to test a recently proposed regional geomorphology paradigm defined by massive south- and southeast-oriented continent... Topographic map evidence from the Wyoming Wind River-Sweetwater River drainage divide area is used to test a recently proposed regional geomorphology paradigm defined by massive south- and southeast-oriented continental ice sheet melt water floods that flowed across the entire Missouri River drainage basin. The new paradigm forces recognition of an ice sheet created and occupied deep “hole” and is fundamentally different from the commonly accepted paradigm in which a pre-glacial north- and northeast-oriented slope would have prevented continental ice sheet melt water from reaching or crossing the Wind River-Sweetwater River drainage divide. Divide crossings (or low points) are identified as places where water once flowed across the drainage divide. Map evidence is interpreted first from the accepted paradigm perspective and second from the new paradigm perspective to determine the simplest explanation. Both paradigm perspectives suggest south-oriented water crossed the drainage divide, although accepted paradigm interpretations do not satisfactorily explain the large number of observed divide crossings and are complicated by the need to bury the Owl Creek and Bridger Mountains to explain why the Wind River now flows in a north direction through Wind River Canyon. New paradigm interpretations explain the large number of divide crossings as diverging and converging channel evidence (as in flood-formed anastomosing channel complexes), Owl Creek and Bridger Mountain uplift to have occurred as south-oriented floodwaters carved Wind River Canyon, and a major flood flow reversal (caused by ice sheet related crustal warping and the opening up of deep “hole” space by ice sheet melting) as being responsible for the Wind River abrupt turn to the north. While this test only addresses topographic map evidence, Occam’s Razor suggests the new paradigm offers what in science should be the preferred Wind River-Sweetwater River drainage divide origin interpretations. 展开更多
关键词 Beaver divide ESCARPMENT CONTINENTAL Ice Sheet Melt Water Floods East-West CONTINENTAL divide Great divide BASIN WIND RIVER BASIN WIND RIVER Mountains
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A Low Power,High Sensitivity SiGe HBT Static Frequency Divider up to 90 GHz for Millimeter-Wave Application 被引量:2
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作者 Peigen Zhou Jixin Chen +2 位作者 Pinpin Yan Debin Hou Wei Hong 《China Communications》 SCIE CSCD 2019年第2期85-94,共10页
A layout and connection optimization for static frequency divider is presented. The layout optimization provides a new circle topology transistors placement and reasonable connection structure, which reduces the paras... A layout and connection optimization for static frequency divider is presented. The layout optimization provides a new circle topology transistors placement and reasonable connection structure, which reduces the parasitic effectively and enables self-oscillation frequency enhancement. Besides, bandwidth enhancement techniques based on a center-tap capacitor in input balun design and inductive peaking in latch design are adopted to improve further high frequency performance with low power consumption. As a proof of concept, design of a divide-by-2 static frequency divider in 0.13 μm SiGe BiCMOS technology is reported. With single-ended input clock signal, the divider is measured to be operated from 40 to 90 GHz. Phase noise measurements of a 90 GHz input clock signal indicate ideal behavior with no measurable noise contribution from the divider. The divider followed by a buffer that can deliver more than-10 dBm output power, which is sufficient to drive succeeding stage. To the author's knowledge, the divider exhibits a competitive power dissipation and the highest FOM among silicon based frequency dividers that operating higher than 70 GHz. 展开更多
关键词 E-band layout optimization MILLIMETER wave integrated circuits STATIC frequency divideR SIGE
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Effects of land use change on the spatiotemporal variability of soil organic carbon in an urban-rural ecotone of Beijing,China 被引量:4
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作者 YE Hui-chun HUANG Yuan-fang +4 位作者 CHEN Peng-fei HUANG Wen-jiang ZHANG Shi-wen HUANGShan-yu HOU Sen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第4期918-928,共11页
Understanding the effects of land use changes on the spatiotemporal variation of soil organic carbon (SOC) can provide guidance for low carbon and sustainable agriculture. In this paper, based on the large-scale dat... Understanding the effects of land use changes on the spatiotemporal variation of soil organic carbon (SOC) can provide guidance for low carbon and sustainable agriculture. In this paper, based on the large-scale datasets of soil surveys in 1982 and 2009 for Pinggu District -- an urban-rural ecotone of Beijing, China, the effects of land use and land use changes on both temporal variation and spatial variation of SOC were analyzed. Results showed that from 1982 to 2009 in Pinggu District, the following land use change mainly occurred: Grain cropland converted to orchard or vegetable land, and grassland converted to forestland. The SOC content decreased in region where the land use type changed to grain cropland (e.g., vegetable land to grain cropland decreased by 0.7 g kg-1; orchard to grain cropland decreased by 0.2 g kg-l). In contrast, the SOC content increased in region where the land use type changed to either orchard (excluding forestland) or forestland (e.g., grain cropland to orchard and forestland increased by 2.7 and 2.4 g kg-1, respectively; grassland to orchard and forestland increased by 4.8 and 4.9 g kg-1, respectively). The organic carbon accumulation capacity per unit mass of the soil increased in the following order: grain cropland soil〈vegetable land/grassland soil〈orchard soil〈forestland soil. Therefore, to both secure supply of agricultural products and develop low carbon agriculture in a modern city, orchard has proven to be a good choice for land using. 展开更多
关键词 land use change soil organic carbon spatiotemporal variability urban-rural ecotone
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Origin of Little Missouri River - South Fork Grand River and nearby Drainage Divides in Harding County, South Dakota and Adjacent Eastern Montana, USA 被引量:5
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作者 Eric Clausen 《Open Journal of Geology》 2017年第8期1063-1077,共15页
Barbed tributaries flowing in southeast directions, an asymmetric drainage divide with both the South Fork Grand River and the North Fork Moreau River, and the Jump-off escarpment-surrounded basin (interpreted here to... Barbed tributaries flowing in southeast directions, an asymmetric drainage divide with both the South Fork Grand River and the North Fork Moreau River, and the Jump-off escarpment-surrounded basin (interpreted here to be a large abandoned headcut) are examples of topographic map evidence suggesting the north oriented Little Missouri River valley eroded headward across a large southeast oriented anastomosing complex of ice-marginal melt water flood flow channels that once crossed Harding County, South Dakota. Additional evidence includes southeast oriented tributaries to the northeast oriented South Fork Grand River and multiple divide crossings (e.g. through valleys and wind gaps) on the Boxelder Creek-Little Missouri River divide (in eastern Montana and west of the Little Missouri River) and suggests deep regional erosion occurred as the north oriented Little Missouri River valley eroded headward into and across the region. Harding County is located south and west of the southwest limit of coarse-grained glacial erratic material and ice-marginal melt water flow routes logically should have crossed it. Deep melt water erosion of Harding County and adjacent eastern Montana regions to the west is not consistent with many previous drainage history and glacial history interpretations, but is consistent with deep erosion by continental ice sheets. 展开更多
关键词 Boxelder Creek Carter COUNTY (Montana) Deep Melt Water Erosion Drainage divide Moreau RIVER Powder RIVER
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