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Evolutionary model of the central place hierarchical system

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Science China Earth Sciences 2011年第10期54卷 1614-1626页

作者： LU YuQi yuan linwang ZHONG YeXi Key Laboratory of VGE Ministry of Education Nanjing Normal University Nanjing 210046 China

Central place theory is one of the two theoretical cornerstones of geography, yet it cannot be connected with other spatial structure models, fails to provide definite time-space parameter conditions, lacks an evolutionary process model, and does not easily enable construction of a complete theoretical system of regional spatial structure. This paper gives an in-depth analysis of the process and mechanism for production and evolution of central places of different grades, and constructs an evolutionary model of the central place hierarchical system. The results of deduction, analysis and simulation show that production and evolution of the central place hierarchical system may be divided into five stages. These stages are the embryonic, formative, improvement, maturation, and advancement stages. Affected by spatial location and centricity, central places have obvious differences in scale and functional structures. There are great differences in the scale of same-grade central places. However, low-grade central places could have larger scales than high-grade central places, and the central places of a central location may form the agglomeration area of central places. Based on the hypothesis condition of an isotropic plain, the research shows that it is possible not only to form proportional functional structures of central places, but also to produce non-proportional scale structures of central places, and thus to complete the transformation from rationalistic deduction of spatial equilibrium mode to an explanation and demonstration of an unbalanced practical model.

关键词： central place theory hierarchical system evolutionary model functional structure scale structure

A 3D GIS spatial data model based on conformal geometric algebra

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Science China Earth Sciences 2011年第1期54卷 101-112页

作者： yuan linwang YU Zhaoyuan LUO Wen ZHOU LiangChen LU GuoNia Key Laboratory of VGE Ministry of Education Nanjing Normal University Nanjing 210046 China

We propose a new Geographic Information System (GIS) three-dimensional (3D) data model based on conformal geometric algebra (CGA). In this approach, geographic objects of different dimensions are mapped to the corresponding basic elements (blades) in Clifford algebra, and the expressions of multi-dimensional objects are unified without losing their geometric meaning. Geometric and topologic computations are also processed in a clear and coordinates-free way. Under the CGA framework, basic geometrics are constructed and expressed by the inner and outer operators. This expression combined geometrics of different dimensions and metric relations. We present the structure of the framework, data structure design, and the data storage, editing and updating mechanisms of the proposed 3D GIS data model. 3D GIS geometric and topological analyses are performed by CGA metric, geometric and topological operators using an object-oriented approach. Demonstrations with 3D residence district data suggest that our 3D data model expresses effectively geometric objects in different dimensions, which supports computation of both geometric and topological relations. The clear and effective expression and computation structure has the potential to support complex 3D GIS analysis, and spatio-temporal analysis.

关键词： conformal geometric algebra 3D data model 3D measurement 3D spatial relation

Disciplinary structure and development strategy of information geography in China

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Journal of Geographical Sciences 2022年第9期32卷 1670-1682页

作者： LI Xin yuan linwang PEI Tao HUANG Xin LIU Guang ZHENG Donghai State Key Laboratory of Tibetan Plateau Earth System Environment and ResourcesInstitute of Tibetan Plateau ResearchCASBeijing100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China Ministry of Education Key Laboratory of Virtual Geographic Environment Nanjing Normal UniversityNanjing210023China State Key Laboratory of Resources and Environment Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China School of Remote Sensing and Information Engineering Wuhan UniversityWuhan430079China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteCASBeijing100094China

The advent of the information era has resulted in exceptional advances in geographic *** domain of geographic science has expanded from traditional physical and human geography to physical,human,and information geography,resulting in the emergence of the field of information *** subdisciplines have gradually formed,i.e.,geographic remote sensing science,geographic information science,and geographic data *** a view towards preparing a description of the disciplinary structure of geographic science for the“Development Strategy of Discipline and Frontier Research in China(2021-2035)”,this article summarizes the history,definition,and disciplinary structure of information *** strategic layout of the discipline,along with the goals and key directions of priority development fields,are also *** insights into this new discipline provided in this paper will promote the development and application of remote sensing and geographic information within the framework of geographic science,advancing the synthesis of geographic research and the integrated development of geographic science.

关键词： information geography geographic remote sensing science geographic information science geographic data science disciplinary structure

Geographic scenario:a possible foundation for further development of virtual geographic environments

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International Journal of Digital Earth 2018年第4期11卷 356-368页

作者： Guonian Lü Min Chen linwang yuan Liangchen Zhou Yongning Wen Mingguan Wu Bin Hu Zhaoyuan Yu Songshan Yue Yehua Sheng Key Laboratory of Virtual Geographic Environment Ministry of Education of PRCNanjing Normal UniversityNanjingPeople’s Republic of China State Key Laboratory Cultivation Base of Geographical Environment Evolution(Jiangsu Province) NanjingPeople’s Republic of China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application NanjingPeople’s Republic of China

It has been two decades since virtual geographic environments(VGEs)were initially *** relevant theories and technologies are evolving,data organization models have always been the foundation of VGE development,and they require further *** on the comprehensive consideration of the characteristics of VGEs,geographic scene is proposed to organize geographic information and *** empirically find that geographic scene provides a suitable organization schema to support geo-visualization,geo-simulation,and *** systematically investigate the concept and method of geographic scene,Geographic Scenario is proposed as the theory on developing geographic scene,and corresponding key issues of the Geographic Scenario are illustrated in this *** of the proposed method are discussed with the hope of informing future studies of VGEs.

关键词： Virtual geographic environments(VGEs) data organization geographic scene geographic scenario

Regional sea level change in Northwest Pacific： Process, characteristic and prediction

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Journal of Geographical Sciences 2011年第3期21卷 387-400页

作者： LUO Wen yuan linwang YU Zhaoyuan YI Lin XIE Zhiren Key Laboratory of Virtual Geographic Environment Ministry of Education Nanjing Normal University Nanjing 210046 China

Based on 22 sparse-distributed tide gauge records in the Northwest Pacific Ocean marginal sea, the process, characteristic and prediction of regional sea level change are discussed by the integration of the following methods. Firstly, the regularized EM algorithm （RegEM） and the Multi-taper Spectral Method （MTM） are adopted to interpret their multiscale fluctuation processes and their spatial-temporal variations. Secondly, the orderly cluster method is introduced to classify these tidal stations, and with the consideration of the space adjacent relation, we obtain five sub-regions （the coasts of Bohai Sea-northern Yellow Sea, Yellow Sea-East China Sea along Chinese coast, the East China Sea along Japanese coast, the southern East China Sea and the northwestern South China Sea）. Furthermore, the Mean Generation Function （MGF） is explored to predict the medium- and long-term trends of each tide station. Finally, the Principal Component Analysis （PCA） is employed to obtain regional-scale sea level change trends, sea level rise rates of the above five sub-regions from 2001 to 2030 are 1.23-1.27 mm/a, 3.30-3.34 mm/a, 2.72-2.76 mm/a, 1.43-1.47 mm/a and 1.13-1.15 mm/a respectively, and the whole region sea level rise rate is between 2.01 mm/a and 2.11 mm/a. The aim of our work is to conduct an integrated research on regional sea level change.

关键词： regional sea level change spatial-temporal variation MTM prediction Northwest Pacific

ENSO signals and their spatial-temporal variation characteristics recorded by the sea-level changes in the northwest Pacific margin during 1965-2005

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Science China Earth Sciences 2009年第5期52卷 869-882页

作者： yuan linwang,YU Zhaoyuan,XIE ZhiRen,SONG ZhiYao & Lü GuoNian School of Geographical Science,Nanjing Normal University,Nanjing 210046,China School of Geographical Science Nanjing Normal University Nanjing 210046 China

Sea-level is closely linked to the Earth's climate and its change is important as a metric for global and regional climate change. Identifying, extracting, and revealing such information through detailed analysis is the prerequisite for understanding the mechanisms of sea-level change. The monthlyaverage tide-change records reported and examined in this paper are from 10 tide gauge stations distributed in the northwest margin of the Pacific Ocean, registered during the period 1965-2005. In particular, we have utilized the Second Order Blind Identification (SOBI) method to identify and the Empirical Mode Decomposition (EMD) method to extract the El Nio-Southern Oscillation (ENSO) signals imprinted in those tide gauge records; and subsequently, we have investigated the spa-tial-temporal characteristics of the extracted ENSO signals using wavelet analysis methods. The following results are obtained: (1) the ENSO events recorded by each tide gauge series are of different types and intensity, which show considerable temporal-spatial variation characteristics, with sea-level responses to ENSO signals remarkably stronger in low latitude areas than in medium-high latitude areas; (2) due to the influences of ocean currents, topographical conditions, and other factors, there exist variations in the type of relationship between the sea-level changes and the recorded ENSO events at different latitudes; (3) sea-level changes can also denote scale-variation characteristics of ENSO events, and particularly, since 1980s, all the tide gauges located south of Kanmen show intense responses to ENSO and the timescale of ENSO events extended gradually from around 4 years to 2-8 years, reflecting variations in the intensity and frequency of ENSO events; and (4) reverse changes of certain scale were noted before and after strong ENSO events recorded by sea-level changes, supporting the research findings about the interaction (mutual coupling and superimposition) between the probability of

关键词： sea level change ENSO SOBI cross wavelet spectrum wavelet coherence

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地理学视角下测绘地理信息再透视

测绘学报 2017年第10期46卷 1549-1556页

作者：闾国年袁林旺俞肇元虚拟地理环境教育部重点实验室(南京师范大学) 江苏南京210023 江苏省地理环境演化国家重点实验室培育建设点江苏南京210023 江苏省地理信息资源开发与利用协同创新中心江苏南京210023

系统回顾了地理信息系统产生以来地理信息内涵发展与拓展的主要历程,指出地理信息的定义一直是在"空间+属性"的地图信息基本框架下逐步扩展,其发展历程经历了地图GIS、语义GIS、时空GIS和大数据GIS 4个不同的阶段,但仍无法满足时空大数... 详细信息

系统回顾了地理信息系统产生以来地理信息内涵发展与拓展的主要历程,指出地理信息的定义一直是在"空间+属性"的地图信息基本框架下逐步扩展,其发展历程经历了地图GIS、语义GIS、时空GIS和大数据GIS 4个不同的阶段,但仍无法满足时空大数据的分析和应用需求。从地理学研究的对象和内容出发,对地理学所需要的"地理信息"的内涵和外延进行了系统的梳理总结,提出了涵盖"空间定位""语义描述""属性特征""几何形态""演化过程""要素相互关系"的地理信息六要素表达模型。在地理定律和地理规律的指导下,面向地理现象空间分布、时空格局、演化过程、相互作用机理的集成表达、系统分析和高效管理,设计了六要素集成表达的几何代数统一GIS数据模型、地理规律与相互作用驱动的新型GIS数据结构、非结构化时空数据组织与存储等关键技术,为测绘地理信息走向地理科学信息提供了另一个理论基础与技术方法支撑,有助于提升GIS对地理格局、演化过程和要素相互作用等地理规律的组织、管理、表达和分析能力。

关键词：地理信息六要素表达模型数据模型数据结构数据库

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基于主张量的时空数据特征驱动可视化方法

应用基础与工程科学学报 2013年第2期21卷 276-286页

作者：罗文袁林旺俞肇元闾国年南京师范大学虚拟地理环境教育部重点实验室江苏南京210046

面向时空场数据高维分析与表达的需求,构建基于主张量的时空数据结构分析与动态表达模型.简述了张量的定义、基本算子及主张量分解方法,给出了基于主张量分解的多维度特征分析流程.利用张量的多维融合特性进行多维时空数据的组织与表达... 详细信息

面向时空场数据高维分析与表达的需求,构建基于主张量的时空数据结构分析与动态表达模型.简述了张量的定义、基本算子及主张量分解方法,给出了基于主张量分解的多维度特征分析流程.利用张量的多维融合特性进行多维时空数据的组织与表达,设计了多维时空数据统一组织与存储方法.利用主张量分解方法,实现了时空数据不同维度结构特征的解析与动态重构,进而建立了基于主张量的多维时空数据多维度解析模型与特征驱动的时空数据联动可视化策略.以赤道太平洋海域卫星测高SSHA(Sea Surface Height Abnormity)网格数据进行实验验证.实现了基于张量的多维透视、子集提取、等值面绘制与时空体可视化等功能.利用主张量分解实现了对ENSO(El Nio-Southern Oscillation)事件时间型与空间型的解析与提取,并实现了时间、经度、纬度系数驱动下的联动可视化.实例验证表明,该方法较好再现了ENSO事件的时空分布格局与动态演化特征,并可实现对ENSO时空演化过程的多维度透视.

关键词：主张量分解时空场特征驱动联动可视化

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盐城麋鹿生态旅游区游客变化特征及预测

地理学报 2007年第12期62卷 1277-1286页

作者：黄震方袁林旺俞肇元南京师范大学地理科学学院南京210046

生态旅游区的发展受到诸多确定性因素和随机性因素的共同作用,并反映于旅游区游客观测序列。通过构建游客序列分析框架,提出了游客序列分析的理论模型。并以江苏盐城麋鹿生态旅游区为例,集成多种数学方法,进行了游客序列的分解、调整和... 详细信息

生态旅游区的发展受到诸多确定性因素和随机性因素的共同作用,并反映于旅游区游客观测序列。通过构建游客序列分析框架,提出了游客序列分析的理论模型。并以江苏盐城麋鹿生态旅游区为例,集成多种数学方法,进行了游客序列的分解、调整和综合预测的实证分析。运用Tramo/Seats方法进行季节调整分析可有效提取时间序列各组分,从而获得了不同尺度的作用模式,所获得的去噪序列为预测研究提供了基础资料。基于ARIMA模型、Winter加法模型、Winter乘法模型和Tramo/Seats模型的综合预测表明,麋鹿生态旅游区未来两年年平均新增游客数量在1.95-3.14万人次之间。各方法预测结果间的差异与其建模思路及实现方法有关,因此集成多种方法进行预测,并进行对比分析,有助于获得对游客波动变化更为全面的认识,同时所提供的多种可能预测方案,可为生态旅游区容量控制、旅游环境资源的保护与开发及旅游区的管理决策提供参考依据。

关键词：游客预测 Tramo/Seats模型 ARIMA模型 Winters模型盐城麋鹿生态旅游区