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中国自然灾害的空间分布特征 被引量:33
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作者 王铮 张丕远 刘啸雷 《地理学报》 CSSCI CSCD 北大核心 1995年第3期248-255,共8页
中国自然灾害的分布以秦岭-淮河线、胡焕庸线以及青藏高原外缘为界,可划分为四个大区,即北域、南域、西域和过渡带亚域。以灾害的单位面积损失论,黄淮海地区是我国重点灾区,另一个重点区位于川、滇、黔、桂交界地段,它以人员的伤... 中国自然灾害的分布以秦岭-淮河线、胡焕庸线以及青藏高原外缘为界,可划分为四个大区,即北域、南域、西域和过渡带亚域。以灾害的单位面积损失论,黄淮海地区是我国重点灾区,另一个重点区位于川、滇、黔、桂交界地段,它以人员的伤亡而突出。如果以灾害发生的总经济损失定义灾害规模,则活动的规模中心位于以洞庭一武汉和郑州为两端点的地区。 展开更多
关键词 自然灾害 空间分间 灾害规模 中国
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Horizontal Distribution and Annual Variations of Fecal Coliform Bacteria in Luoyuan Bay 被引量:2
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作者 蔡雷鸣 《Marine Science Bulletin》 CAS 2010年第1期48-58,共11页
Fecal Coliform Bacteria (FCB) of marine waters was monitored in Luoyuan Bay from January, 2003 to December, 2005. The results showed that number of FCB in marine water samples ranged from no detection ( 〈2 cfu/100... Fecal Coliform Bacteria (FCB) of marine waters was monitored in Luoyuan Bay from January, 2003 to December, 2005. The results showed that number of FCB in marine water samples ranged from no detection ( 〈2 cfu/100 mL) to 540 cfu/100 mL in Luoyuan Bay. Values of FCB during August to October were significantly higher than those during January to April during three year period. Monthly changes of FCB values at each year period were mainly due to monthly precipitation. In addition, compared with FCB values in difference sample sites, values of FCB in Bay-heed were significantly higher than those in middle of bay and Bay-mouth, Luoyuan Bay. However, values of FCB in Bay-mouth were significantly less than those in middle of bay. The ratios to the par of FCB in 2003, 2004, and 2005 years were 100%, 98.0%, and 97.9%, respectively. Therefore, we considered that the pollution of FCB of surface marine water in Luoyuan Bay was not serious. 展开更多
关键词 Luoyuan Bay fecal coliform bacteria horizontal distribution annual variations
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Optimal shape space and searching in the active shape model
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作者 何良华 邹采荣 +1 位作者 赵力 胡蝶 《Journal of Southeast University(English Edition)》 EI CAS 2005年第3期263-267,共5页
A novel idea,called the optimal shape subspace (OSS) is first proposed for optimizing active shape model (ASM) search.It is constructed from the principal shape subspace and the principal shape variance subspace.I... A novel idea,called the optimal shape subspace (OSS) is first proposed for optimizing active shape model (ASM) search.It is constructed from the principal shape subspace and the principal shape variance subspace.It allows the reconstructed shape to vary more than that reconstructed in the standard ASM shape space,hence it is more expressive in representing shapes in real life.Then a cost function is developed,based on a study on the search process.An optimal searching method using the feedback information provided by the evaluation cost is proposed to improve the performance of ASM alignment.Experimental results show that the proposed OSS can offer the maximum shape variation with reserving the principal information and a unique local optimal shape is acquired after optimal searching.The combination of OSS and optimal searching can improve the ASM performance greatly. 展开更多
关键词 active shape model shape subspace search subspace principal component analysis
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Mapping Theorems on Quasi-Nagata Spaces
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作者 夏省祥 于正文 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期57-61,共5页
In this paper, we discuss the relationship between k-semi-stratifiable spaces and quais-Nagata spaces and some mapping properties of quasi-Nagata spaces. We get following results: sequence-covering closed mapping pres... In this paper, we discuss the relationship between k-semi-stratifiable spaces and quais-Nagata spaces and some mapping properties of quasi-Nagata spaces. We get following results: sequence-covering closed mapping preserve quasi-Nagata spaces, and finite-to-one open mappings don't preserve quasi-Nagata spaces. 展开更多
关键词 quasi-Nagata space k-semi-stratifiable space sequencecovering mapping
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A spectrum measurement system for arc plasma with time and spatial indentification
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作者 李志勇 冯立 +1 位作者 杨军涛 范力予 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第1期75-82,共8页
Spectrum analysis of the plasma has over the years been growing both in methods and instrument, which makes it become a widely used non-contact detection method, without disturbing the arc plasma itself. With noticeab... Spectrum analysis of the plasma has over the years been growing both in methods and instrument, which makes it become a widely used non-contact detection method, without disturbing the arc plasma itself. With noticeable developments in the industry application of the method, a need for careful analysis of the plasma with both time and space identification is desirable. Therefore, a spectral measurement system is developed in this paper for diagnosing arc plasma with time and space identification. With a new hollow probe scanning method, the instrument can be used to provide information like energy distribution of plasma, temperature within the arc plasma, which are of great significance with the requirement of space identification. Furthermore, the system can also be used to capture the instant state of the arc plasma with the synchronic triggering system, which uses high speed photo and electrical signal as the time criterion. The industry applications prove that the system works well for online detection of the arc plasma. 展开更多
关键词 SPECTRUM PLASMA time identification space identification
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SEPARATED FRAMES
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作者 张凤玲 StraussDona 《Transactions of Tianjin University》 EI CAS 1998年第1期76-79,共4页
In this paper we shall offer a separation axiom for frames inspired by the Hausdorff separation axiom for topological spaces. We call it separated condition. This is a condition on topology OX equivalent to the ... In this paper we shall offer a separation axiom for frames inspired by the Hausdorff separation axiom for topological spaces. We call it separated condition. This is a condition on topology OX equivalent to the T O space X being Hausdorff. The class of separated frames includes that of strong Hausdorff frames and that of S frames. We shall show that the class of separated frames is a class closed under the formation of coproducts and subspaces, and the space Fil( L ) is Hausdorff for any separated frame L . Therefore there is a contravariant adjunction between the category TOP 2 of Hausdorff topological spaces and the category FRAM 2 of separated frames. 展开更多
关键词 FRAME separated frame Hausdorff topological space adjunction between categories
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Gully Erosion Regionalization of Black Soil Area in Northeastern China 被引量:16
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作者 YANG Jiuchun ZHANG Shuwen +3 位作者 CHANG Liping LI Fei LI Tianqi GAO Yan 《Chinese Geographical Science》 SCIE CSCD 2017年第1期78-87,共10页
Gully erosion is the frequent and main form of soil erosion in the black soil area of the northeastern China, which is one of the most important commodity grain production bases in China. It is encroaching upon the fe... Gully erosion is the frequent and main form of soil erosion in the black soil area of the northeastern China, which is one of the most important commodity grain production bases in China. It is encroaching upon the fertile farmland there. Regionalization of gully erosion can reveal the spatial distribution and regularity of the development of gully erosion. Based on the eco-geographical regional background features of the black soil area, this study combined the regionalization with influencing factors of the development of gully erosion. GIS spatial analysis, geostatistical analysis, spatial statistics, reclassification, debris polygon processing and map algebra methods were employed. As a result, the black soil area was divided into 12 subregions. The field survey data on type, length, volume and other characteristics indicators of gully erosion were used to calibrate the results. Then the features of every subregion, such as where the gully erosion is, how serious it is, and why it happens and develops, were expounded. The result is not only an essential prerequisite for gully erosion surveys and monitoring, but also an important basis for gully erosion prevention. 展开更多
关键词 regionalization gully erosion soil and water conservation black soil area northeastern China
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THERMAL EFFECTS OF BUILDING′S EXTERNAL SURFACES IN CITY——Characteristics of Heat Flux into and out of External Wall Surfaces 被引量:2
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作者 ZHANGYi-ping HEYun-ling +3 位作者 LIUYu-hong MAYou-xin LIYou-rong DOUJun-xia 《Chinese Geographical Science》 SCIE CSCD 2004年第4期343-349,共7页
This study examined the thermal effects of building′s external wall surfaces, using observational data of spatial-temporal distribution of surface temperature, air temperature, and heat flux into and out of external ... This study examined the thermal effects of building′s external wall surfaces, using observational data of spatial-temporal distribution of surface temperature, air temperature, and heat flux into and out of external surface. Results indicate that external wall surface temperature and nearby air temperature vary with the change of orientation, height and season. In general, the external wall surface temperature is lower near the ground, and is higher near the roof, than nearby air temperature. But north wall surface temperature is mostly lower than nearby air temperature at the same height; south wall surface temperature during the daytime in December, and west wall surface temperature all day in August, is respectively higher than nearby air temperature. The heat fluxes into and out of external wall surfaces show the differences that exist in the various orientations, heights and seasons. In December, south wall surface at the lower sites emits heat and north wall surface at the higher sites absorbs heat. In April, all external wall surfaces, emit heat near the ground and absorb heat near the roof. In August, west wall surface all day emits heat, and other wall surfaces just show the commensurate behavior with that in April. 展开更多
关键词 external wall surface thermal effect heat flux intensity spatial-temporal distribution
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Simulation Analysis on Spatial Pattern of Urban Population in Shenyang City,China in Late 20th Century 被引量:5
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作者 QIN Zhiqin ZHANG Pingyu 《Chinese Geographical Science》 SCIE CSCD 2011年第1期110-118,共9页
The spatial distribution of urban population can reflect significantly urban functions and development status. Shenyang, as a typical old industrial city in China, has experienced considerable changes in spatial distr... The spatial distribution of urban population can reflect significantly urban functions and development status. Shenyang, as a typical old industrial city in China, has experienced considerable changes in spatial distribution of population in the process of urban transformation, resulting in the change of urban spatial structure. Based on the sub-district data of Chinese national population censuses in 1982, 1990 and 2000, this study simulates the evolution pattern of spatial distribution of urban population in Shenyang City. Using statistical method and exploratory spatial data analysis (ESDA), we found that the population distribution, on the whole, has presented a balanced and decentralized trend since the 1980s, which characterizes with Chinese suburbanization. Furthermore, based on the investigation of the pattern of population distribution, it is concluded that the negative exponential model fitted the distribution best, and population concentration in the inner suburb kept increasing gradually, meanwhile, the spatial structure of population distribution has presented a polycentric feature since the 1980s. The parameters of the model show that population in the urban core concentrate significantly all the time. The increase of population in the inner suburb influences the population distribution pattern more and more importantly, but the concentration intensity of population cores in inner suburb is still low. 展开更多
关键词 population distribution urban spatial structure simulation analysis Shenyang City
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Spatial Autocorrelation Analysis on Regional Economic Disparity of Northeast Economic Region in China 被引量:6
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作者 Li Fei Zhou Chenghu 《Chinese Journal of Population,Resources and Environment》 2009年第2期27-31,共5页
Popular regional inequality indexes such as variation coefficient and Gini coefficient can only reveal overall inequality, and have limited ability in revealing spatial dependence or spatial agglomeration. Recently so... Popular regional inequality indexes such as variation coefficient and Gini coefficient can only reveal overall inequality, and have limited ability in revealing spatial dependence or spatial agglomeration. Recently some methods of exploratory spatial data analysis such as spatial autocorrelation have provided effective tools to analyze spatial agglomeration and cluster, which can reveal the pattern of regional inequality. This article attempts to use spatial autocorrelation at county level to get refined spatial pattern of regional disparity in Chinese northeast economic region over 2000-2006 (2001 absent). The result indicates that the basic trend of regional economy is an increasing concentration of growth among counties in northeast economic region, and there are two geographical clusters of poorer counties including the counties in western Liaoning Province and adjacent counties in Inner Mongolia, poorer counties of Heihe, Qiqihar and Suihua in Heilongjiang Province. This article also reveals that we can use the methods of exploratory spatial data analysis as the supplementary analysis methods in regional economic analysis. 展开更多
关键词 regional disparity spatial analysis northeast economic region spatial autocorrelation
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Spatial Patterns of Car Sales and Their Socio-economic Attributes in China 被引量:1
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作者 LIU Daqian LO Kevin +1 位作者 SONG Wei XIE Chunyan 《Chinese Geographical Science》 SCIE CSCD 2017年第5期684-696,共13页
Using data from the Economic Advisory Center of the State Information Center(SIC), we examined the spatial patterns of car sales in China at the prefectural level in 2012. We first analyzed the spatial distributions o... Using data from the Economic Advisory Center of the State Information Center(SIC), we examined the spatial patterns of car sales in China at the prefectural level in 2012. We first analyzed the spatial distributions of car sales of different kinds of automakers(foreign automakers, Sino-foreign joint automakers, and Chinese automakers), and then identified spatial clusters using the local Moran's indexes. Location quotient analysis was applied to examine the relative advantage of each type of automaker in the local markets. To explain the variations of car sales across cities, we collected several socioeconomic variables and conducted regression analyses. Further, factor analysis was used to extract independent variables to avoid the problem of multicollinearity. By incorporating a spatial lag or spatial error in the models, we calibrated our spatial regression models to address the spatial dependence problem. The analytical results show that car sales varied significantly across cities in China, and most of the cities with higher car sales were the developed cities. Different automakers exhibit diverse spatial patterns in terms of car sales volume, spatial clusters, and location quotients. The scale and incomes factor were extracted and verified as the two most significant and positive factors that shape the spatial distributions of car sales, and together with the spatial effect, explained most of the variations of car sales across cities. 展开更多
关键词 car sales spatial clusters Location Quotient socio-economic attributes China
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Some Properties of Marcinkiewicz Integral on Herz-type Hardy Spaces
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作者 王伟民 王月山 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第4期88-93,共6页
It provides the boundary proof of Marcnkiewicz integral μ Ω(f)(x) on Herz_type Hardy spaces. That is: if n(1-1q)≤α【n(1-1q)+β then μ Ω(f)(x) is boundendess from H K· α,p q(R n) to ... It provides the boundary proof of Marcnkiewicz integral μ Ω(f)(x) on Herz_type Hardy spaces. That is: if n(1-1q)≤α【n(1-1q)+β then μ Ω(f)(x) is boundendess from H K· α,p q(R n) to K· α,p q(R n); if α=n(1-1q)+β then μ Ω(f)(x) is boundedness from H K· α,p q(R n) to W K· α,p q(R n). 展开更多
关键词 Marcinkiewicz integral Herz space weak Herz space Herz_type Hardy space
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Multi-domain High-Resolution Platform for Integrated Spectroscopy and Microscopy Characterizations 被引量:1
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作者 Li Wang Shen-long Jiang +1 位作者 Qun Zhang Yi Luo 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第6期680-685,I0002,共7页
In recent decades,materials science has experienced rapid development and posed increasingly high requirements for the characterizations of structures,properties,and performances.Herein,we report on our recent establi... In recent decades,materials science has experienced rapid development and posed increasingly high requirements for the characterizations of structures,properties,and performances.Herein,we report on our recent establishment of a multi-domain(energy,space,time)highresolution platform for integrated spectroscopy and microscopy characterizations,offering an unprecedented way to analyze materials in terms of spectral(energy)and spatial mapping as well as temporal evolution.We present several proof-of-principle results collected on this platform,including in-situ Raman imaging(high-resolution Raman,polarization Raman,low-wavenumber Raman),time-resolved photoluminescence imaging,and photoelectrical performance imaging.It can be envisioned that our newly established platform would be very powerful and effective in the multi-domain high-resolution characterizations of various materials of photoelectrochemical importance in the near future. 展开更多
关键词 Multi-domain platform Spectral/spatial/temporal resolution Integrated characterizations SPECTROSCOPY MICROSCOPY Imaging
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HQ-Tree: A Distributed Spatial Index Based on Hadoop 被引量:5
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作者 FENG Jun TANG Zhixian WEI Mian XU Liming 《China Communications》 SCIE CSCD 2014年第7期128-141,共14页
In this paper,we propose a novel spatial data index based on Hadoop:HQ-Tree.In HQ-Tree,we use PR QuadTrec to solve the problem of poor efficiency in parallel processing,which is caused by data insertion order and spac... In this paper,we propose a novel spatial data index based on Hadoop:HQ-Tree.In HQ-Tree,we use PR QuadTrec to solve the problem of poor efficiency in parallel processing,which is caused by data insertion order and space overlapping.For the problem that HDFS cannot support random write,we propose an updating mechanism,called "Copy Write",to support the index update.Additionally,HQ-Tree employs a two-level index caching mechanism to reduce the cost of network transferring and I/O operations.Finally,we develop MapReduce-based algorithms,which are able to significantly enhance the efficiency of index creation and query.Experimental results demonstrate the effectiveness of our methods. 展开更多
关键词 spatial index QUADTREE HADOOP MAPREDUCE
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City Size Distribution and Its Spatiotemporal Evolution in China 被引量:4
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作者 SHI Lifeng ZHANG Zengxiang +8 位作者 LIU Fang ZHAO Xiaoli WANG Xiao LIU Bin HU Shunguang WEN Qingke ZUO Lijun YI Ling XU Jinyong 《Chinese Geographical Science》 SCIE CSCD 2016年第6期703-714,共12页
Based on the National Land Use/Cover Database of China(NLUD-C) in the end of the 1980s(the 1980s,hereafter), 1995, 2000, 2005, and 2010, 665 cities were selected to study the size distribution and its changes of urban... Based on the National Land Use/Cover Database of China(NLUD-C) in the end of the 1980s(the 1980s,hereafter), 1995, 2000, 2005, and 2010, 665 cities were selected to study the size distribution and its changes of urban lands in China. In this study, the spatiotemporal evolutions of urban land size distribution as well as the influence of administrative-level on these cities were explored by combining urban spatial positions and administrative-levels. Results indicate that: 1) City size distribution using urban lands was more practical and reasonable than using non-agricultural population. 2) In the 1980s, cities with ascending urban land rank were centralized in Eastern China, specially the Changjiang(Yangtze) River Delta, the Zhujiang(Pearl) River Delta, and Beijing-Tianjin-Hebei region. Cities in Central, Western, and Northeast China mainly indicated descending urban land rank. 3) The transfer of national development focus resulted in cities with ascending urban land rank becoming evenly distributed nationwide; however, this trend was slightly centralized around Chengdu, Chongqing, and Wuhan in different periods. 4) During the 1980s to 2010, the proportion of cities with ascending urban land rank in provincial capitals, municipalities, and special administrative regions(high-level cities, hereafter) was consistently higher than those in prefecture- and county-level cities except for 2005–2010. The ranks of the majority of the prefecture- and county-level cities were mainly descending, supported by ascending; the proportion of cities with unchanged rank is small. This study breaks through the bottleneck of traditional research in the area of city size distribution by examining urban land replacing the non-agricultural population. The current study also provides scientific explanation for the healthy and reasonable development of urban land as well as the coordinated development of population urbanization and land urbanization. 展开更多
关键词 Chinese city urban land size distribution spatiotemporal evolution remote sensing
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Tourism Competitiveness Evaluation and Spatio-temporal Characteristics of Chinese Border Counties 被引量:4
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作者 SHI Yuqing ZHONG Linsheng +1 位作者 CHEN Tian YU Hu 《Chinese Geographical Science》 SCIE CSCD 2016年第6期817-828,共12页
Under the current government strategy of building a Silk Road economic belt, tourism in Chinese border counties has becoming increasingly popular. Studying tourism competitiveness in Chinese border counties is of siza... Under the current government strategy of building a Silk Road economic belt, tourism in Chinese border counties has becoming increasingly popular. Studying tourism competitiveness in Chinese border counties is of sizable theoretical and practical importance, as there are several notable factors involved. In this study, we constructed a tourism competitiveness evaluation model based on eight factors: natural environment, tourism resource, location and transportation, social environment, tourism service facility, border port, tourism industrial cluster and tourism market. We then analyzed the spatial characteristics of tourism competitiveness in border counties and identified five types of border counties: resource advantage type(RA), border-port advantage type(PA), location advantage type(LA), agglomeration advantage type(AA), and relative balance type(RB), and examined the correlation between tourism market competitiveness and interior competitiveness factors in the counties from 2006 to 2011. Results showed that tourism resource, location and transportation, and tourism service facility are the most important competition factors for RA border counties during the study period. Competition factors in PA counties transferred from tourism resource, social environment and tourism service facility to border port and tourism industrial cluster; competition factors in LA counties transferred from natural environment and tourism resource to tourism service facility and tourism industrial cluster and border port. Competition factors in AA counties transferred from tourism service facility to tourism resource. Tourism industrial cluster, tourism service facility and tourism resource proved to be important competition factors in RB counties. The findings of this study can be used to target tourism strategies according to different county types. 展开更多
关键词 border counties tourism competiveness spatio-temporal characteristics type classification
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Suburbanization and Subcentering of Population in Beijing Metropolitan Area:A Nonparametric Analysis 被引量:3
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作者 SUN Tieshan HAN Zhenhai +1 位作者 WANG Lanlan LI Guoping 《Chinese Geographical Science》 SCIE CSCD 2012年第4期472-482,共11页
This study focuses on the suburbanization and subcentering of population and examines the nature of spatial restructuring in terms of the population distribution in the Beijing metropolitan area.Instead of the classic... This study focuses on the suburbanization and subcentering of population and examines the nature of spatial restructuring in terms of the population distribution in the Beijing metropolitan area.Instead of the classic density function approach,we employ the nonparametric analysis to characterize the spatial pattern of population densities in the Beijing metropolitan area and identify the suburban subcenters.Our findings suggest that the population has spread with rapid urban growth in the Beijing metropolitan area,and the compact urban form has been replaced by a more dispersed polycentric spatial distribution.However,compared with the decentralization of western cities,the spatial extent of the decentralization of population in the Beijing metropolitan area is quite limited.The rapid growth of population in the near suburbs has expedited the sprawl of the central city,with a larger central agglomeration of population dominating the metropolitan area.In this sense,the spatial pattern of the Beijing metropolitan area is still characterized by the continuous compactness.However,our findings do provide the evidence that the city has been turning to a polycentric structure.We find significant population subcenters have emerged in the suburbs of Beijing since the 1980s.But the polycentricity emerged in the Beijing metropolitan area is very different by nature from that observed in Western cities.The subcenters emerged are adherent to the development scheme planned for the city,so it can be referred to as the so called 'planned polycentricity'. 展开更多
关键词 SUBURBANIZATION population subcenters POLYCENTRICITY urban spatial structure Beijing metropolitan area
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Pressure gradient errors in a covariant method of implementing theσ-coordinate:idealized experiments and geometric analysis 被引量:1
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作者 LI Jin-Xi LI Yi-Yuan WANG Bin 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第4期270-276,共7页
A new approach is proposed to use the covariant scalar equations of the a-coordinate (the covariant method), in which the pressure gradient force (PGF) has only one term in each horizontal momentum equation, and t... A new approach is proposed to use the covariant scalar equations of the a-coordinate (the covariant method), in which the pressure gradient force (PGF) has only one term in each horizontal momentum equation, and the PGF errors are much reduced in the computational space. In addition, the validity of reducing the PGF errors by this covariant method in the computational and physical space over steep terrain is investigated. First, the authors implement a set of idealized experiments of increasing terrain slope to compare the PGF errors of the covariant method and those of the classic method in the computational space. The results demonstrate that the PGF errors of the covariant method are consistently much-reduced, compared to those of the classic method. More importantly, the steeper the terrain, the greater the reduction in the ratio of the PGF errors via the covariant method. Next, the authors use geometric analysis to further investigate the PGF errors in the physical space, and the results illustrates that the PGF of the covariant method equals that of the classic method in the physical space; namely, the covariant method based on the non-orthogonal a-coordinate cannot reduce the PGF errors in the physical space. However, an orthogonal method can reduce the PGF errors in the physical space. Finally, a set of idealized experiments are carried out to validate the results obtained by the geometric analysis. These results indicate that the covariant method may improve the simulation of variables relevant to pressure, in addition to pressure itself, near steep terrain. 展开更多
关键词 Pressure gradient forceerrors covariant scalarequations of the o-coordinate steep terrain computational andphysical space geometricanalysis non-orthogonala-coordinate
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Temporal Data Mining Using Genetic Algorithm and Neural Network——A Case Study of Air Pollutant Forecasts 被引量:1
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作者 Shine-Wei Lin Chih-Hong Sun Chin-Han Chen 《Geo-Spatial Information Science》 2004年第1期31-38,共8页
This paper integrates genetic algorithm and neura l network techniques to build new temporal predicting analysis tools for geographic information system (GIS). These new GIS tools can be readily applied in a practical... This paper integrates genetic algorithm and neura l network techniques to build new temporal predicting analysis tools for geographic information system (GIS). These new GIS tools can be readily applied in a practical and appropriate manner in spatial and temp oral research to patch the gaps in GIS data mining and knowledge discovery functions. The specific achievement here is the integration of related artificial intellig ent technologies into GIS software to establish a conceptual spatial and temporal analysis framework. And, by using this framework to develop an artificial intelligent spatial and tempor al information analyst (ASIA) system which then is fully utilized in the existin g GIS package. This study of air pollutants forecasting provides a geographical practical case to prove the rationalization and justness of the conceptual tempo ral analysis framework. 展开更多
关键词 GIS TEMPORAL data mining genetic algorithm neural network
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Spatial Disparity and Efficiency of Science and Technology Resources in China 被引量:2
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作者 WANG Bei LIU Weidong +1 位作者 LU Dadao ZHANG Jianbo 《Chinese Geographical Science》 SCIE CSCD 2012年第6期730-741,共12页
In the knowledge economy era,science and technology(S&T) resources are getting more and more important in shaping regional competiveness and building regional innovation capacity.As such,the spatial distribution o... In the knowledge economy era,science and technology(S&T) resources are getting more and more important in shaping regional competiveness and building regional innovation capacity.As such,the spatial distribution of S&T resources is a key to understanding regional development and disparities.By designing an input-output indicator system,this paper develops an evaluation model to examine the spatial distribution of S&T resources in China and assess their spatial efficiency.Moreover,the paper tries to explain spatial differences in the efficiency of S&T resources in China.Major findings are:1) the input and output of S&T resources in China shows a clear T-shaped spatial structure,i.e.,concentrated mainly in the coastal region and along the Changjiang(Yangtze) River;2) the efficiency of S&T resources in China displays strong spatial disparities,with the level of efficiency descending from the east to the west while high efficiency appearing in only several clusters;3) the utilization rates of S&T resources in most provinces are quite low,resulting in low efficiency of S&T resources allocation.The paper suggests that the utilization rate of S&T resources should be raised and the commercialization of S&T outputs should be enhanced to improve the efficiency of S&T resources in China. 展开更多
关键词 science and technology resources resources spatial allocation resources-utilization efficiency China
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