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Spatial-temporal Differentiation of Sauna Days with Different Intensities in China from 1961 to 2017
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作者 Feng KONG 《Agricultural Biotechnology》 CAS 2019年第6期75-82,共8页
Sauna weather with high temperature, high humidity and long standby time has become one of the main meteorological hazards faced by urban residents. Based on the daily maximum temperature and relative humidity dataset... Sauna weather with high temperature, high humidity and long standby time has become one of the main meteorological hazards faced by urban residents. Based on the daily maximum temperature and relative humidity datasets of 545 meteorological observation stations in China from 1961 to 2017, the spatial-temporal evolution characteristics of sauna days with different intensities in China were studied from three aspects: climatic state, trend and fluctuation characteristics, using the standard of sauna days defined by the Central Meteorological Observatory of China Meteorological Administration. The results showed that: firstly, the spatial pattern of sauna days with different intensities in China was high in southeast China and low in northwest China from 1961 to 2017, and the spatial pattern of sauna days with the same intensity in different research periods had little difference, which was in good agreement with the spatial pattern of sauna days with corresponding intensities in the whole research period. With the increase of intensity, the sauna days in China decreases gradually. Secondly, the trend of sauna days with different intensities in China was bounded by Hu Huanyong Line from 1961 to 2017, showing a pattern of increasing or decreasing mosaic in the southeast China and mainly decreasing trend, while the spatial differentiation pattern in the northwest China changed little. The trend of sauna days with different intensities in China increased significantly in 1991-2017 compared with 1961-1990. Thirdly, the fluctuation of sauna days with different intensities in China was bounded by Hu Huanyong Line, showing a spatial pattern of large fluctuations in the southeast China and small fluctuations in the northwest China. And the fluctuation of sauna days and heavy sauna days showed obvious threeblock distribution characteristics. The fluctuation characteristics of sauna days with different intensities in China from 1961 to 1990 and 1991 to 2017 were in good agreement with the whole research period. The fluctuation difference before and after 1990 mainly concentrated in the vicinity of Hu Huanyong Line and its southeast area, and the fluctuation differences increased mainly, indicating that the variation of sauna days with different intensities in the southeast China increased from 1991 to 2017. 展开更多
关键词 Sauna weather High temperature and heat waves Spatial pattern Interdecadal variation Climate change Regional differentiation
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The spatial-temporal pattern and influencing factors of negative air ions in urban forests, Shanghai, China 被引量:25
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作者 Hong Liang Xiaoshuang Chen +1 位作者 Junguang Yin Liangjun Da 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第4期847-856,共10页
Negative air ions are natural components of the air we breathe Forests are the main continuous natural source of negative air ions (NAI). The spatio-temporal patterns of negative air ions were explored in Shanghai, ... Negative air ions are natural components of the air we breathe Forests are the main continuous natural source of negative air ions (NAI). The spatio-temporal patterns of negative air ions were explored in Shanghai, based on monthly monitoring in 15 parks from March 2009 to February 2010. In each park, sampling sites were selected in forests and open spaces. The annual variation in negative air ion concentrations (NAIC) showed peak values from June to October and minimum values from December to January. NAIC were highest in summer and autumn, intermediate in spring, and lowest in winter. During spring and summer, NAIC in open spaces were significantly higher in rural areas than those in suburban areas. However, there were no significant differences in NAIC at forest sites among seasons. For open spaces, total suspended particles (TSP) were the dominant determining factor of NAIC in sum- mer, and air temperature and air humidity were the dominant determining factors of NAIC in spring, which were tightly correlated with Shanghai's ongoing urbanization and its impacts on the environment. R is suggested that urbanization could induce variation in NAIC along the urban-rural gradient, but that may not change the temporal variation pattern. Fur- thermore, the effects of urbanization on NAIC were limited in non-vegetated or less-vegetated sites, such as open spaces, but not in well-vegetated areas, such as urban forests. Therefore, we suggest that urban greening, especially urban forest, has significant resistance to theeffect of urbanization on NAIC. 展开更多
关键词 negative air ion concentration spatial-temporal pattern URBANIZATION urban ecosystem urban greening
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Spatial-temporal pattern changes of main agriculture natural disasters in China during 1990-2011 被引量:11
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作者 DU Xindong JIN Xiaobin +2 位作者 YANG Xilian YANG Xuhong XIANG Xiaomin 《Journal of Geographical Sciences》 SCIE CSCD 2015年第4期387-398,共12页
China is a disaster prone country, and a comprehensive understanding of change of disasters is very important for China's agricultural development. In this study, statistical tech niques and geographic information sy... China is a disaster prone country, and a comprehensive understanding of change of disasters is very important for China's agricultural development. In this study, statistical tech niques and geographic information system tools are employed to quantify the main agricul ture disasters changes and effects on grain production in China during the period of 1990-2011. The results show that China's grain production was severely affected by disas ters including drought, flood, hail, frost and typhoon. The annual area covered by these dis asters reached up to 48.7x106 ha during the study period, which accounted for 44.8% of the total sown area, and about 55.1% of the per unit area grain yield change was caused by disasters. In addition, all of the disasters showed high variability, different changing trends, and spatial distribution. Drought, flood, and hail showed significantly decreasing trends, while frost and typhoon showed increasing trends. Drought and flood showed gradual changes and were distributed across the country, and disasters became more diversified from north to south. Drought was the dominated disaster type in northern China, while flood was the most important disaster type in the southern part. Hail was mainly observed in central and northern China, and frost was mainly distributed in southern China. Typhoon was greatly limited to the southeast coast. Furthermore, the resilience of grain production of each province was quite different, especially in several major grain producing areas, such as Shandong, Liaoning, Jilin and Jiangsu, where grain production was seriously affected by disasters. One reason for the difference of resilience of grain production was that grain production was marginalized in developed provinces when the economy underwent rapid development. For China's agricul tural development and grain security, we suggest that governments should place more em phasis on grain production, and invest more money in disaster prevention and mitigation, especially in the major grain producing provinces. 展开更多
关键词 spatial-temporal pattern grain production DISASTERS China
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NDVI spatial pattern and its differentiation on the Mongolian Plateau 被引量:14
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作者 张雪艳 胡云锋 +2 位作者 庄大方 齐永清 马欣 《Journal of Geographical Sciences》 SCIE CSCD 2009年第4期403-415,共13页
GIMMS NDVI database and geo-statistics were used to depict the spatial distribution and temporal stability of NDVI on the Mongolian Plateau.The results demonstrated that:(1) Regions of interest with high NDVI indices ... GIMMS NDVI database and geo-statistics were used to depict the spatial distribution and temporal stability of NDVI on the Mongolian Plateau.The results demonstrated that:(1) Regions of interest with high NDVI indices were distributed primarily in forested mountainous regions of the east and the north,areas with low NDVI indices were primarily distributed in the Gobi desert regions of the west and the southwest,and areas with moderate NDVI values were mainly distributed in a middle steppe strap from northwest to southeast.(2) The maximum NDVI values maintained for the past 22 years showed little variation.The average NDVI variance coefficient for the 22-year period was 15.2%.(3) NDVI distribution and vegetation cover showed spatial autocorrelations on a global scale.NDVI patterns from the vegetation cover also demonstrated anisotropy;a higher positive spatial correlation was indicated in a NW-SE direction,which suggested that vegetation cover in a NW-SE direction maintained increased integrity,and vegetation assemblage was mainly distributed in the same specific direction.(4) The NDVI spatial distribution was mainly controlled by structural factors,88.7% of the total spatial variation was influenced by structural and 11.3% by random factors.And the global autocorrelation distance was 1178 km,and the average vegetation patch length(NW-SE) to width(NE-SW) ratio was approximately 2.4:1.0. 展开更多
关键词 GIMMS NDVI spatial pattern spatial differentiation spatial statistics Mongolian Plateau
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Spatial-temporal patterns of China's interprovincial migration, 1985-2010 被引量:7
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作者 LI Yang LIU Hui +2 位作者 TANG Qing LU Dadao XlAO Ningchuan 《Journal of Geographical Sciences》 SCIE CSCD 2014年第5期907-923,共17页
Migration plays an increasing role in China's economy since mobility rose and economic restructuring has proceeded during the last three decades. Given the background of most studies focusing on migration in a partic... Migration plays an increasing role in China's economy since mobility rose and economic restructuring has proceeded during the last three decades. Given the background of most studies focusing on migration in a particular period, there is a critical need to analyze the spatial-temporal patterns of migration. Using bicomponent trend mapping technique and interprovincial migration data during the periods 1985-1990, 1990-1995, 1995-2000, 2000- 2005, and 2005-2010 we analyze net-, in-, out-migration intensity, and their changes over time in this study. Strong spatial variations in migration intensity were found in China's interprovincial migration, and substantial increase in migration intensity was also detected in eastern China during 1985-2010. Eight key destinations are mostly located within the three rapidly growing economic zones of eastern China (Pearl River Delta, Yangtze River Delta and Beijing-Tianjin-Hebei Metropolitan Region), and they are classified into three types: mature, emerging, and fluctuant origins, while most key origins are relatively undeveloped central and western provinces, which are exactly in accordance with China's economic development patterns. The results of bicomponent trend mapping indicate that, in a sense, the migration in the south was more active than the north over the last three decades. The result shows the new changing features of spatial-temporal patterns of China's interprovincial migration that Fan and Chen did not find out in their research. A series of social-economic changes including rural transformation, balanced regional development, and labor market changes should be paid more attention to explore China's future interprovincial migration. 展开更多
关键词 China spatial-temporal pattern interprovincial migration bicomponent trend mapping economicand cultural factors
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Spatial-temporal pattern and formation mechanism of county urbanization on the Chinese Loess Plateau 被引量:2
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作者 SONG Yong-yong MA Bei-bei +3 位作者 DAI Lan-hai XUE Dong-Qian XIA Si-you WANG Peng-tao 《Journal of Mountain Science》 SCIE CSCD 2021年第4期1093-1111,共19页
Urbanization is a comprehensive and complex socioeconomic phenomenon that plays an influential role in promoting global socioeconomic development.The Loess Plateau region is an important part of the China’s ecologica... Urbanization is a comprehensive and complex socioeconomic phenomenon that plays an influential role in promoting global socioeconomic development.The Loess Plateau region is an important part of the China’s ecological security pattern,and occupies an important position in the implementation of China’s new-type urbanization strategy and the realization of the urban dream.The characteristics of the staged changes and regional differentiation of urbanization in the area from 1990 to 2018 were studied with focus on regions and subregions by selecting 341 county-level administrative units on the Chinese Loess Plateau as the research area,and employing partition analysis and geographic detector methods.This revealed the formation mechanism of the spatial differentiation pattern of urbanization on the Loess Plateau.We found that the urbanization of the Loess Plateau,previously in a slow growth phase,entered the accelerated development phase,presenting a macro pattern of high rates of urbanization in central and eastern areas and low rates in western areas.The formation of the regional differentiation patterns of urbanization on the Loess Plateau were the combined results of natural geographical and socioeconomic factors.Among these factors,the interaction of any two factors had a stronger impact on regional urbanization patterns than a single factor,which was specifically manifested as nonlinear or bi-factor enhancement effects.The findings of this paper may provide a theoretical reference and scientific basis for the scientific promotion of healthy urbanization on the Chinese Loess Plateau and the ecologically fragile areas of developing countries around the world. 展开更多
关键词 URBANIZATION spatial-temporal pattern Influencing factors Driving mechanism Geographical detector Chinese Loess Plateau
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Guidelines on common cold for Traditional Chinese Medicine based on pattern differentiation 被引量:5
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作者 Yang Jiao Jianping Liu +5 位作者 Liangduo Jiang Qingquan Liu Xiaoli Li Shunan Zhang Baixiao Zhao Tianfang Wang 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第4期417-422,共6页
OBJECTIVE: To establish the guidelines on common cold treated with Traditional Chinese Medicine (TCM) in terms of pattern identification. METHODS: The guidelines were formulated by using the basic patterns of common c... OBJECTIVE: To establish the guidelines on common cold treated with Traditional Chinese Medicine (TCM) in terms of pattern identification. METHODS: The guidelines were formulated by using the basic patterns of common cold in ChinaPharmacopeia integrated with findings from systematic literature review and the experts' consensus on the issue in question. RESULTS: Common cold was divided into four patterns in the guidelines. The medications were recommended respectively: Ganmaoqingre granule for wind-cold exterior syndrome,Yinqiaojiedu granule for wind-heat exterior syndrome, Huoxiangzhengqi Wan for summer-heat dampness exterior syndrome and Shensu Wan for wind-cold exterior syndrome accompanied with Qi deficiency. CONCLUSION: The guidelines were primarily derived from the practice experience of TCM and the experts' consensus. The process was not strictly evidence-based because of lacking enough clinical studies. Further refinement of the guidelines should be needed as more studies are available. 展开更多
关键词 Common cold Practice guideline Medicine Chinese traditional pattern differentiation
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Logical thinking in pattern differentiation of Traditional Chinese Medicine 被引量:2
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作者 Jing Zhou Jiankun Zhu +4 位作者 Meijuan Chen Miao Jiang Zongming Zhang Zhen Zhan Xu Zhang 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第1期137-140,共4页
OBJECTIVE: To discuss the application of logic to pattern differentiation for treatment in Traditional Chinese Medicine (TCM). METHODS: Comparing logic reasoning of syllogism with the logical thinking ofTCM pattern di... OBJECTIVE: To discuss the application of logic to pattern differentiation for treatment in Traditional Chinese Medicine (TCM). METHODS: Comparing logic reasoning of syllogism with the logical thinking ofTCM pattern differentiation for treatment. RESULTS:TCM logical thinking depends on symbolic and intuitive judgment with abstractive reasoning integrated into the process. Although it lacks quantitative measurement, it pays great attention to the comprehensive analysis of a disease's cause and its development patterns to get insight into the essence of illness. CONCLUSION: TCM diagnosis reasoning methodmay lack rigorousness, continuity, systematic induction and deduction, but its logical thinking still can attain its goal following a process with rigorous, regulated and scientific formal logic. 展开更多
关键词 LOGIC Traditional Chinese Medicine pattern differentiation SYLLOGISM
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Control of paleogeographic pattern on sedimentary differentiation of evaporite-carbonate symbiotic system:A case study of the sixth sub-member of Ordovician Majiagou Formation M5 Member in central-eastern Ordos Basin,NW China 被引量:4
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作者 ZHONG Shoukang TAN Xiucheng +8 位作者 HU Guang NIE Wancai YANG Mengying ZHANG Daofeng ZHENG Jianfeng XU Jie DONG Guodong XIAO Di LU Zixing 《Petroleum Exploration and Development》 CSCD 2022年第4期837-850,共14页
The relationship between paleogeographic pattern and sedimentary differentiation of evaporite-carbonate symbiotic system is examined based on logging,core and thin section data,by taking the sixth sub-member of fifth ... The relationship between paleogeographic pattern and sedimentary differentiation of evaporite-carbonate symbiotic system is examined based on logging,core and thin section data,by taking the sixth sub-member of fifth member of Ordovician Majiagou Formation(M56)in the central-eastern Ordos Basin as an example.(1)Seven sub-geomorphic units(Taolimiao west low,Taolimiao underwater high,Taolimiao east low,Hengshan high,East salt low,North slope and Southwest slope)developed in the study area.(2)The“three lows”from west to east developed dolomitic restricted lagoon,evaporite evaporative lagoon and salt evaporative lagoon sedimentary facies respectively,the"two highs"developed high-energy grain beach and microbial mound,and the north and south slopes developed dolomitic flats around land.(3)The paleogeographic pattern caused natural differentiation of replenishment seawater from the northwest Qilian sea,leading to the eccentric sedimentary differentiation of dolomite,evaporite and salt rock symbiotic system from west to east,which is different from the classic“bull's eye”and“tear drop”distribution patterns.(4)As the Middle Qilian block subducted and collided into the North China Plate,the far-end compression stress transferred,giving rise to the alternate highland and lowland in near north to south direction during the sedimentary period of M56 sub-member.(5)Taolimiao underwater high and Hengshan high developed favorable zones of microbial mounds and grain shoals in south to north strike in M56 sub-member,making them favorable exploration areas with great exploration potential in the future. 展开更多
关键词 paleogeographic pattern sedimentary differentiation evaporite and carbonate rock favorable reservoir facies zone Ordovician Majiagou Formation Ordos Basin
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Spatial-temporal analysis of wetland landscape pattern under the influence of artificial dykes in the Yellow River delta 被引量:1
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作者 Xin Fu Gaohuan Liu +2 位作者 Siyue Chai Chong Huang Fadong Li 《Chinese Journal of Population,Resources and Environment》 2013年第2期109-117,共9页
The influence of anthropogenic activities,especially artificial dykes,on the coastal wetland landscape is now considered as a serious problem to the coastal ecosystem.It is important and necessary to analyze changes o... The influence of anthropogenic activities,especially artificial dykes,on the coastal wetland landscape is now considered as a serious problem to the coastal ecosystem.It is important and necessary to analyze changes of coastal landscape pattern under the influence of artificial dykes for the protection and management of coastal wetland.Our study aimed to reveal the quantitative characteristics of the coastal wetland landscape and its spatial-temporal dynamics under the influence of artificial dykes in the Yellow River delta(YRD).It was analyzed by the methods of the statistical analysis of landscape structure,five selected landscape indices and the changes of spatial centroids of three typical wetland types,including reed marshes,tidal fiats and aquaculture-salt fields.The results showed that:(1)Reduction of wetland area,especially the degradation of natural wetlands,had been the principal problem since the dykes were constructed in the YRD.The dykes created conditions for the development of artificial wetlands.However,the new born artificial wetlands were still less than the vanished natural wetlands.(2)Compared with the open area,the building of artificial dykes significantly speeded up the changes of landscape patterns and the aggravation of the landscape fragmentation in the closed area.(3)The changes of area-weighted centroids of three typical wetland landscapes were greatly affected by dykes,and the movement of the centroid of the aquaculture-salt field was very sensitive to the dykes constructed in the corresponding period. 展开更多
关键词 artificial DYKES COASTAL WETLAND COASTAL zone of the YELLOW River DELTA LANDSCAPE pattern spatial-temporal analysis
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Spatial differentiation pattern of interregional migration in ethnic minority areas of Yunnan Province, China 被引量:1
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作者 ZHAO Mei-feng WANG De-gen 《Journal of Mountain Science》 SCIE CSCD 2021年第11期3041-3057,共17页
Interregional migration has broad and far-reaching impacts on regional urbanization process in ethnic minority areas of Southwest China.The previous literature of interregional migration paid less attention on the eth... Interregional migration has broad and far-reaching impacts on regional urbanization process in ethnic minority areas of Southwest China.The previous literature of interregional migration paid less attention on the ethnic minority areas with fragile geographical feature and marginal socio-economic context in the developing world due to the dearth of reliable data.Based on the 2015 national 1%population sampling survey at the village/community scale,taking Yulong Naxi Autonomous County,Yunnan Province,China as the case study,this paper analyzed the spatial differentiation pattern.The results showed that:(1)migration in Yulong Naxi Autonomous County exhibited obvious spatial differentiation characteristics in terms of population aggregation,population loss,migration direction,and migration activity;(2)the overall spatial differentiation of migration exhibited a"layer+sector"pattern in Yulong Naxi Autonomous County:the first layer was active areas with net inflows(<20 km from the seat of the county government),the second layer was inactive areas(within 20–60 km of the seat of the county government),and the third layer was a mixed"layer+sector"zone(>60 km to the seat of the county government),comprised of inactive areas and active areas with net outflows;(3)the spatial differentiation pattern of migration was highly correlated with the regional contexts including the regional economic development,regional transportation accessibility and regional social development,while regional physical geographical factors had insignificant relationships with the migration pattern. 展开更多
关键词 Interregional migration Spatial differentiation pattern Regional contexts Ethnic minority area Southwest China
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Patterns, processes, and differentiation mechanisms of China's transition from old to new economic drivers 被引量:1
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作者 YAN Mingtao ZHAO Jianji YAN Mingyue 《Journal of Geographical Sciences》 SCIE CSCD 2024年第9期1697-1718,共22页
Transition from old to new economic drivers(TONED) is of great significance for optimizing economic structures. Using a combination of methods including entropy weight technique for order preference by similarity to i... Transition from old to new economic drivers(TONED) is of great significance for optimizing economic structures. Using a combination of methods including entropy weight technique for order preference by similarity to ideal solution, geospatial analysis, and optimal parameter geodetector, this study investigates the patterns and mechanisms of China's TONED in the prefecture-level cities from 2011 to 2020. The findings reveal that(1) the TONED exhibited a spatial distribution characterized by higher levels in the east and lower levels in the west, along with a pyramidal hierarchy of levels. The distribution of hot and cold spots roughly followed the Heihe-Yulin line.(2) The informatization levels, openness to the outside world, and urbanization played a dominant role in the TONED. The types of dual-factor interactions exhibited both dual-factor enhancement and non-linear enhancement effects.(3) The eastern and central regions were more likely to promote the TONED through enhanced informatization levels, whereas the western region relied more on increasing openness. This study finds that the TONED results from the combined effects of three geographical natures, each playing a distinct role. The recommendations provided can serve as a reference for China and other developing countries to implement the TONED in the context of deglobalization. 展开更多
关键词 transition from old to new economic drivers pattern evolution differentiation mechanism geographical nature China
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Comparing the effectiveness of pattern differentiation treatment and fixed formula treatment for perimenopausal syndrome with Chinese herbal medicine:A study protocol 被引量:1
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作者 Wingsze Hsu Manhon Chan +7 位作者 Sirong Zheng Kingchung Li Kamyin Chan Hoiyi Lam Tammy Tinyan Chu Siufung Chan Yingching Kwok Linda LD.Zhong 《Journal of Traditional Chinese Medical Sciences》 CAS 2023年第3期331-338,共8页
Objective:To further understand and compare the effectiveness of pattern differentiation treatment and fixed prescription treatment in perimenopausal syndrome.Methods:The study will be conducted in the Hong Kong Feder... Objective:To further understand and compare the effectiveness of pattern differentiation treatment and fixed prescription treatment in perimenopausal syndrome.Methods:The study will be conducted in the Hong Kong Federation of Trade Unions Workers'Medical Clinics,Hong Kong Baptist University Chinese Medicine Clinic cum Training and Research Centre(Hong Kong,China).One hundred Chinese women,aged 45-55 years,will be recruited.The participants will be randomized into 2 groups.The intervention group will be administered medication,based on pattern differentiation,by qualified traditional Chinese medicine(TCM)practitioners.After each evaluation,TCM practitioners will evaluate and revise the prescription,based on the participants'patterns.The control group will be given the standard formula,i.e.,the Erxian decoction,which contains 6 herbs.The treatment period and the follow-up period will be 8 weeks each.The primary assessment outcome measure will be the Kupperman Index,and the secondary outcome measure will be the Menopause-specific Quality of Life Questionnaire score.Conclusion:Pattern-differentiated treatment is the basic principle of TCM to understand and treat diseases.The study will show the pattern-differentiated treatment is effectiveness than the fixed prescription. 展开更多
关键词 pattern differentiation treatment PERIMENOPAUSAL Chinese herbal medicine Kupperman index Menopause-specific quality of life
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The Spatial-Temporal Distribution Patterns of Dyke Swarms in Central Asia and their Tectonic Significance: Case Studies in Eastern Tianshan and Western Junggar 被引量:1
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作者 FENG Qianwen LI Jinyi LIU Jianfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期152-153,共2页
Dykes are a special kind of intrusive rocks which were formed by deep magma intruded into the existing brittle fractures in the crust.Dykes swarms in different tectonic environments are very significant to re-construc... Dykes are a special kind of intrusive rocks which were formed by deep magma intruded into the existing brittle fractures in the crust.Dykes swarms in different tectonic environments are very significant to re-construct the 展开更多
关键词 deep Asia Case Studies in Eastern Tianshan and Western Junggar The spatial-temporal Distribution patterns of Dyke Swarms in Central Asia and their Tectonic Significance
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A spatial-temporal analysis of urban recreational business districts: A case study in Beijing, China 被引量:15
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作者 ZHU He LIU Jiaming +2 位作者 CHEN Chen LIN Jing TAO Hui 《Journal of Geographical Sciences》 SCIE CSCD 2015年第12期1521-1536,共16页
This study has revealed spatial-temporal changes in Recreational Business Dis- tricts (RBDs) in Beijing and examined the relationship between the location of urban RBDs and traffic conditions, resident and tourist d... This study has revealed spatial-temporal changes in Recreational Business Dis- tricts (RBDs) in Beijing and examined the relationship between the location of urban RBDs and traffic conditions, resident and tourist density, scenic spots, and land prices. A more reasonable classification of urban RBDs (LSC, CPS, and ULA) is also proposed. Quantitative methods such as Gini Coefficient, Spatial Interpolation, Kernel Density Estimation, and Geographical Detector were employed to collect and analyze the data from three types of urban RBDs in Beijing in 1990, 2000, and 2014, respectively, and the spatial-temporal pat- terns as well as the distribution characteristics of urban RBDs were analyzed using ArcGIS software. It was concluded that (1) both the number and scale of urban RBDs in Beijing have been expanding and the trend for all types of urban RBDs in Beijing to be spatially agglom- erated is continuing; (2) the spatial-temporal evolution pattern of urban RBDs in Beijing is "single-core agglomeration-dual-core agglomeration-multi-core diffusion"; and (3) urban RBDs were always located in areas with low traffic density, tourist attractions, high resident and tourist population density, and relatively high land valuations; these factors also affect the scale size of RBDs. 展开更多
关键词 urban RBD spatial-temporal pattern distribution characteristics BEIJING
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Compressed ghost imaging based on differential speckle patterns 被引量:5
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作者 Le Wang Shengmei Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第2期294-300,共7页
We propose a compressed ghost imaging scheme based on differential speckle patterns,named CGI-DSP.In the scheme,a series of bucket detector signals are acquired when a series of random speckle patterns are employed to... We propose a compressed ghost imaging scheme based on differential speckle patterns,named CGI-DSP.In the scheme,a series of bucket detector signals are acquired when a series of random speckle patterns are employed to illuminate an unknown object.Then the differential speckle patterns(differential bucket detector signals)are obtained by taking the difference between present random speckle patterns(present bucket detector signals)and previous random speckle patterns(previous bucket detector signals).Finally,the image of object can be obtained directly by performing the compressed sensing algorithm on the differential speckle patterns and differential bucket detector signals.The experimental and simulated results reveal that CGI-DSP can improve the imaging quality and reduce the number of measurements comparing with the traditional compressed ghost imaging schemes because our scheme can remove the environmental illuminations efficiently. 展开更多
关键词 GHOST imaging compressed sensing differentiAL SPECKLE patterns differentiAL BUCKET DETECTOR SIGNALS
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Spatial-temporal evolution of vegetation evapotranspiration in Hebei Province,China 被引量:5
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作者 WANG Qian-feng TANG Jia +6 位作者 ZENG Jing-yu QU Yan-ping ZHANG Qing SHUI Wei WANG Wu-lin YI Lin LENG Song 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第9期2107-2117,共11页
Evapotranspiration (ET) is the sum of soil or water body evaporation and plant transpiration from the earth surface and ocean to the atmosphere, and thus plays a significant role in regulating carbon and water resou... Evapotranspiration (ET) is the sum of soil or water body evaporation and plant transpiration from the earth surface and ocean to the atmosphere, and thus plays a significant role in regulating carbon and water resource cycles. The time-series data set from the remote sensing MOLDS product (MOD16) was used to study the spatial-temporal evolution of vegetation evapotranspiration in salinized areas during 2000-2014 by analyzing the variability, spatial patterns and Mann-Kendall (MK) nonparametric trends for the time series. The results indicate that inter-annual and intra-annual variations of ET across various vegetated areas show seasonal changes, with the abnormal months identified. The Cultivated land displays a greater degree of spatial heterogeneity and the spatial pattern of ET in the area covered by broadleaved deciduous forests corresponds to a higher ET rate and increased water consumption. Awidespread decline of ET is observed only in cultivated areas. However, agricultural cultivation doesn't worsen water shortage and soil salinization problems in the region, and water shortage problems are worsening for other vegetated areas. This research provides a basis of reference for the reasonable allocation of water resources and restructuring of vegetation patterns in salinized areas. 展开更多
关键词 EVAPOTRANSPIRATION Hebei Province MODIS spatial pattern VEGETATION spatial-temporal evolution
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Spatial-temporal Heterogeneity of Industrial Structure Transformation and Carbon Emission Effects in Xuzhou Metropolitan Area 被引量:3
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作者 QIU Fangdao YUAN He +1 位作者 BAI Liangyu LI Fei 《Chinese Geographical Science》 SCIE CSCD 2017年第6期904-917,共14页
Employing decoupling index and industrial structure characteristic bias index methods, this study analyzed the spatial-temporal characteristics of industrial structure transformations and their resulting carbon emissi... Employing decoupling index and industrial structure characteristic bias index methods, this study analyzed the spatial-temporal characteristics of industrial structure transformations and their resulting carbon emissions in the Xuzhou Metropolitan Area from 2000 to 2014, with a focus on their relationships and driving factors. Our research indicates that carbon emission intensity from industrial structures in the Xuzhou Metropolitan Area at first showed an increasing trend, which then decreased. Furthermore, the relationship between emissions and industrial economic growth has been trending toward absolute decoupling. From the perspective of the center-periphery, the Xuzhou Metropolitan Area formed a concentric pattern, where both progress towards low emissions and the level of technological advancement gradually diminished from the center to the periphery. In terms of variation across provinces, the ISCB index in the eastern Henan has decreased the slowest, followed by the southern Shandong and the northern Anhui, with the northern Jiangsu ranking last. During this period, resource-and labor-intensive industries were the primary growth industries in the northern Anhui and the eastern Henan, while labor-intensive industries dominated the southern Shandong and capital-intensive industries dominated the northern Jiangsu. In terms of city types, the spatial pattern for industrial structure indicates that recession resource-based cities had higher carbon emission intensities than mature resource-based cities, followed by non-resource-based cities and regenerative resource-based cities. Generally, the industrial structure in the Xuzhou Metropolitan Area has transformed from being resource-intensive to capital-intensive, and has been trending toward technology-intensive as resource availability has been exploited to exhaustion and then been regenerated. Industrial structure has been the leading factor causing heterogeneity of carbon emission intensities between metropolitan cities. Therefore, the key to optimizing the industrial structure and layout of metropolitan areas is to promote industrial structure transformation and improve the system controlling collaborative industrial development between cities. 展开更多
关键词 industrial structure transformation industrial structure characteristic bias carbon emission effect spatial-temporal pattern Xuzhou Metropolitan Area
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Characteristics of Regional Differentiation of Urbanization Development in Anhui Province 被引量:2
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作者 SHI Fei CHU Jin-ong GU Kang-kang 《Asian Agricultural Research》 2011年第4期107-111,116,共6页
On the basis of connotation of urbanization,by using SPSS factor analysis and cluster analysis,we establish index system of urbanization development level and conduct quantitative analysis on development level of urba... On the basis of connotation of urbanization,by using SPSS factor analysis and cluster analysis,we establish index system of urbanization development level and conduct quantitative analysis on development level of urbanization in 17 prefecture-level city of Anhui Province,in order to find out the differentiation pattern of regional space of urbanization development in Anhui Province based on these.The results show that Anhui's difference of urbanization gradient is prominent.Classification of three clusters shows that the pattern of status quo of urbanization development in Anhui Province is'dual-nucleus'and'two-stretches';classification of five clusters show that the pattern of status quo of urbanization development in Anhui Province is'one-core','one-strip'and'three-region'.From five aspects,namely natural geography,transportation location,resources distribution,economic development and administrative system,we analyze the reason and influencing factors of differentiation of urbanization development in the region.The results of three clusters and five clusters show that there is great possibility that'dual-nucleus'changes into'individual-nucleus';'one-core'and'one-strip'may evolve into'one-group'.We should foster the urban agglomeration in central Anhui;perfect structure system in the perspective of integration and fostering;strengthen infrastructure construction and regional coordination system;elevate comprehensive competitiveness and guide holistic development of regional economy;promote industrialization process and promote development level of urbanization. 展开更多
关键词 Urbanization level Regional differentiation Spatial pattern Anhui Province China
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A Research Review of the "Differential Pattern" Theory and Its Contemporary Value
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作者 Han Jianfu 《International Journal of Technology Management》 2015年第12期32-33,共2页
The "differential pattern" is an important thesis raised by Fei Xiaotong in his early sociology theory and possesses unique theoretical intension and practical value. From different dimensions, the study of the "di... The "differential pattern" is an important thesis raised by Fei Xiaotong in his early sociology theory and possesses unique theoretical intension and practical value. From different dimensions, the study of the "differential pattern" theory and its contemporary value has been one of the hot issues in domestic sociology. With these studies, the contents of the "differential pattern" theory are enriched, and also its value boundary and contemporary significance are revealed. 展开更多
关键词 differential pattern Contemporary Value
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