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12篇 您的检索式:作者名="Cheng Changxiu"
    题名 作者 年代 出处 被引量
1Exploring detailed urban-rural development under intersecting population growth and food production scenarios: Trajectories for China’s most populous agricultural province to 2030显示文摘Henan,China,is likely the most populous agricultural province worldwide.It is China’s major grain-producing area,with a continuously increasing population(96 million),which is greater than 93%of countries worldwide.However,this province has been experiencing unprecedented urbanization recently due to national policies and measures,such as a plan to build the capital city of Henan into a national center,resulting in severe conflicts in land use that endanger food security regionally and globally.To facilitate decision-making on this problem,we explored the detailed urban-rural development of Henan by modeling these land-use conflicts.Conventional modeling of a region’s urban-rural development is to navigate trade-offs(a)solely between different land-use types(b)by assuming that each type provides a single service(e.g.,croplands produce all the food),and(c)under a polynomial regression-based projection of population.In contrast,we considered both land-use type and intensity,resulting in a detailed land system for Henan.By introducing the concept of land system services(e.g.,food production),we established a many-to-many relationship between land system classes and services.These allowed us to carry out the most comprehensive modeling of Henan’s urban-rural development under eighteen combined scenarios of population growth and land-use policies on food production.The modeling results of these scenarios provide a solid basis for making decisions regarding Henan’s urban-rural development.We also revealed the influence mechanism of population growth,land-use policies,and their combinations,highlighting the benefits of securing food production by agricultural intensification rather than merely expanding the area of cropland.GAO Peichao XIE Yiru SONG Changqing CHENG Changxiu YE Sijing 2023Journal of Geographical Sciences2023,33,2:2
2Spatial-temporal Distribution Characteristics of Global Seismic Clusters and Associated Spatial Factors显示文摘Earthquakes exhibit clear clustering on the earth. It is important to explore the spatial-temporal characteristics of seismicity clusters and their spatial heterogeneity. We analyze effects of plate space, tectonic style, and their interaction on characteristic of cluster.Based on data of earthquakes not less than moment magnitude(M_w) 5.6 from 1960 to 2014, this study used the spatial-temporal scan method to identify earthquake clusters. The results indicate that seismic spatial-temporal clusters can be classified into two types based on duration: persistent clusters and burst clusters. Finally, we analysed the spatial heterogeneity of the two types. The main conclusions are as follows: 1) Ninety percent of the persistent clusters last for 22-38 yr and show a high clustering likelihood;ninety percent of the burst clusters last for 1-1.78 yr and show a high relative risk. 2) The persistent clusters are mainly distributed in interplate zones, especially along the western margin of the Pacific Ocean. The burst clusters are distributed in both intraplate and interplate zones, slightly concentrated in the India-Eurasia interaction zone. 3) For the persistent type, plate interaction plays an important role in the distribution of the clusters’ likelihood and relative risk. In addition, the tectonic style further enhances the spatial heterogeneity. 4) For the burst type,neither plate activity nor tectonic style has an obvious effect on the distribution of the clusters’ likelihood and relative risk. Nevertheless,interaction between these two spatial factors enhances the spatial heterogeneity, especially in terms of relative risk.YANG Jing CHENG Changxiu SONG Changqing SHEN Shi ZHANG Ting NING Lixin 2019Chinese Geographical Science2019,29,4:2
3Cross-national Perspectives on Using Sustainable Development Goals(SDGs) Indicators for Monitoring Sustainable Development: A Database and Analysis显示文摘Sustainable development is the theme of the 21st century. To monitor the progress of sustainable development, the United Nations launched Sustainable Development Goals(SDGs) in 2015. Subsequently, nations of the world have drawn up a list of localized indicators regarding the United Nations SDGs as a paradigm. We established a database including SDGs indicator systems of 11 economies by collecting and determining a large number of materials. Based on this database, we analyzed SDGs indicators by designing a conceptual framework of comparative analysis that included three views. We found that the SDGs indicator systems of 11 economies are different between the number of indicators, the proportion of different categories, and the connotation of indicators. Although the SDGs indicator systems among economies regarded the United Nations SDGs as a framework and included the major social problems related to sustainability, the inconsistency between SDGs indicator systems is large. It is a major reason why scholars lack the systematic method for developing indicators. There are challenges faced in data accessibility. The framework for comparative analysis could be applied to different economies.WANG Xiangyu SONG Changqing CHENG Changxiu YE Sijing SHEN Shi 2021Chinese Geographical Science2021,31,4:2
4Extensions of GAP-Tree and Its Implementation Based on a Non-topological Data Model显示文摘Cheng Changxiu Niu Fangqu Cai Jun 2008International Journal of Geographical Information Science2008,22,6:1
5(2008) Ex- tensions of GAP-tree and its implementation based on a non-topological data model 显示文摘Cheng Changxiu Niu Fangqu Cai Jtm 2008International Journal of Geographical Information Science2008,,:1
6Spatio-temporal differentiation of spring phenology in China driven by temperatures and photoperiod from 1979 to 2018显示文摘Large amounts of data accumulated in ecology and related environmental sciences arouses urgent need to explore useful patterns and information in it.Here we propose coclustering-based methods and a temperatures-photoperiod driven phenological model to explore spatio-temporal differentiation in long-term spring phenology in China.First,we created the first bloom date(FBD)dataset in China from 1979 to 2018 using the extended spring indices and China Meteorological Forcing Dataset.Then we analyzed the dataset using Bregman block average co-clustering algorithm with I-divergence(BBAC_I)and kmeans algorithm.Such analysis delineated the spatially-continuous phenoregions in China for the first time.Results showed three spatial patterns of FBD in China and their temporal dynamics for 40 years(1979–2018).More specifically,overall late spring onsets occur in 1979–1996,in which areas located in Jiangxi,northern Xinjiang and middle Inner Mongolia experienced constant changing spring onsets.Overall increasingly earlier spring onsets occur in 1997–2012,in which areas located in Fujian,Hunan and eastern Heilongjiang experienced the most variable spring onsets.Stable early spring onsets over China occur after 2012.Results also showed 15 temporal patterns of spring phenology over the study period and their spatial delineation in China.More specifically,most areas in China have the same FBD category for 40 years while northern Guizhou,Hunan and southern Hubei have the same category in 1979–1997 and then fluctuate between different categories.Finally,our results have certain directive significance on the design of existing observational sites in Chinese Phenological Network.Xiaojing WU Changxiu CHENG Cancan QIAO Changqing SONG 2020Science China Earth Sciences2020,63,10:1
7A quantitative scale-setting approach for building multi-scale spatial databases显示文摘Cheng Changxiu Lu Feng Cai Jun 2009Computers & Geosciences2009,35,11:1
8Development and Achievements of Drilling Techniques in Sichuan Oil Province显示文摘DevelopmentandAchievementsofDrillingTechniquesinSichuanOilProvince¥XiaShumingandChengChangxiu(SichuanPetroleumAdininistration...Xia Shuming and Cheng Changxiu(Sichuan Petroleum Adininistration) 1995China Oil & Gas1995,2,3:0
9The Generic Annular Bucket Histogram for Estimating the Selectivity of Spatial Selection and Spatial Join显示文摘Selectivity estimation is crucial for query optimizers choosing an optimal spatial execution plan in a spatial database management system.This paper presents an Annular Bucket spatial histogram(AB histogram)that can estimate the selectivity in finer spatial selection and spatial join operations even when the spatial query has more operators or more joins.The AB histogram is represented as a set of bucket-range,bucket-count value pairs.The bucket-range often covers an annular region like a sin-gle-cell-sized photo frame.The bucket-count is the number of objects whose Minimum Bounding Rectangles(MBRs)fall between outer rectangle and inner rectangle of the bucket-range.Assuming that all MBRs in each a bucket distribute evenly,for every buck-et,we can obtain serial probabilities that satisfy a certain spatial selection or join conditions from the operations' semantics and the spatial relations between every bucket-range and query ranges.Thus,according to some probability theories,spatial selection or join selectivity can be estimated by the every bucket-count and its probabilities.This paper also shows a way to generate an updated AB histogram from an original AB histogram and those probabilities.Our tests show that the AB histogram not only supports the selectivity estimation of spatial selection or spatial join with 'disjoint','intersect','within','contains',and 'overlap' operators but also provides an approach to generate a reliable updated histogram whose spatial distribution is close to the distribution of ac-tual query result.Changxiu Cheng Chenghu Zhou Rongguo Chen 2011Geo-Spatial Information Science2011,14,4:0
10Risk Assessment of Tsunamis Along the Chinese Coast Due to Earthquakes显示文摘China’s coastal areas are densely populated,economically developed, and located in close proximity to several potential tsunami sources;therefore, tsunami risk cannot be ignored. This study assessed tsunami risk in coastal areas of China by developing a framework for tsunami risk assessment from the perspectives of hazards,vulnerability, and exposure. First, a probabilistic tsunami hazard assessment(PTHA) model was applied to estimate the potential tsunami sources in both local crustal faults and circum-Pacific subduction zones based on numerical simulations. The output of the PTHA includes tsunami wave height distributions along the coast. Then, an indicator system reflecting exposure and vulnerability to tsunamis in the coastal areas of China was established by using the entropy method and analytic hierarchy process.The PTHA findings show that the tsunami wave height is close to 3 m on the southern coast of the Bohai Sea, the Pearl River Estuary, and the Yangtze River Delta and exceeds 2 m near the Taiwan Strait for the 2000-year return period. The results of the tsunami risk assessment show that the cities at the highest risk level(level I) include Tangshan, Yantai, and Hong Kong, while cities at the high risk level(level II) include Fuzhou, Xiamen, and Quanzhou near the Taiwan Strait and many cities on the Yangtze River Delta, the Pearl River Estuary, and the southern coast of the Bohai Sea. Our findings can provide an understanding of differences in tsunami risk between Chinese coastal cities that may be affected by tsunamis in the future.Chun Hui Lixin Ning Changxiu Cheng 2022International Journal of Disaster Risk Science2022,13,2:0
11Novel approaches to the multiscalar display of vector data显示文摘There are many challenges to achieving quality multiscalar displays of vector data in geographical information system(GIS).Acknowledging and making use of the differences between traditional cartographic generalization and multiscalar display in GIS,this paper focuses on novel approaches to the definition of small objects and the establishment of scale sequence.The ease of implementation and efficacy of the solutions proposed are exemplified and analyzed.Possibilities for further research into the multiscalar display of vector data in GIS are thereby suggested.NIU Fangqu CHENG Changxiu 2012Geo-Spatial Information Science2012,15,4:0
12An accurate selectivity estimation method for window queries and an implementation thereof显示文摘Spatial selectivity estimation is crucial to choose the cheapest execution plan for a given query in a query optimizer.This article proposes an accurate spatial selectivity estimation method based on the cumulative density(CD)histograms,which can deal with any arbitrary spatial query window.In this method,the selectivity can be estimated in original logic of the CD histogram,after the four corner values of a query window have been accurately interpolated on the continuous surface of the elevation histogram.For the interpolation of any corner points,we first identify the cells that can affect the value of point(x,y)in the CD histogram.These cells can be categorized into two classes:ones within the range from(0,0)to(x,y)and the other overlapping the range from(0,0)to(x,y).The values of the former class can be used directly,whereas we revise the values of any cells falling in the latter class by the number of vertices in the corresponding cell and the area ratio covered by the range from(0,0)to(x,y).This revision makes the estimation method more accurate.The CD histograms and estimation method have been implemented in INGRES.Experiment results show that the method can accurately estimate the selectivity of arbitrary query windows and can help the optimizer choose a cheaper query plan.Changxiu CHENG Jing YANG Xiaomei SONG Shanli YANG Lijun WANG 2015Geo-Spatial Information Science2015,18,2:0
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