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Constructing, Mapping, and Analyzing Global Urban Forest Databases Using Hyperlinks: A World of Vast Unevenness and Research Challenges
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作者 Stanley D. Brunn Olena Dronova Mahmuda Sharmin 《Natural Resources》 2025年第1期1-23,共23页
A distinctive feature of scholarly communities today is exploring topics and concepts in interdisciplinary and international contexts. This observation is increasingly apparent and visible in advancing our thinking an... A distinctive feature of scholarly communities today is exploring topics and concepts in interdisciplinary and international contexts. This observation is increasingly apparent and visible in advancing our thinking and policies related to human/environmental worlds at local, regional, and global scales. Maps are an important part of these innovative and ongoing research approaches. In this context, we consider urban forests a topic meriting more attention of scholars studying the geographic and environmental intersections of the natural sciences with the social sciences and humanities. We construct two innovative knowledge bases, one a conceptual framework based on major themes and concepts related to mapping urban forests using key words of the first 100 results of a Google Scholar query and a second using the number of Google Scholar hyperlinks about mapping urban forests in 244 capital cities. We discovered that the constructed world maps reveal vast global unevenness in our knowledge about urban forests in hyperlink numbers and ratios, results that merit further attention by disciplinary, international and interdisciplinary scholarly communities. 展开更多
关键词 Urban Forests database mapPING Google Scholar HYPERLINKS DISPARITIES Unevenness
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A multi-scale optimal interpolation method of high computational efficiency for mapping oceanic data
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作者 Ying Wen Zhijin Li +1 位作者 Wenlong Ma Xingliang Jiang 《Acta Oceanologica Sinica》 2025年第11期245-258,共14页
Ocean observations are inherently characterized by irregular temporal and spatial distributions,as well as heterogeneous spatial resolutions and error characteristics arising from the use of diverse observational plat... Ocean observations are inherently characterized by irregular temporal and spatial distributions,as well as heterogeneous spatial resolutions and error characteristics arising from the use of diverse observational platforms and techniques.To enable their application across a broad range of scientific and practical problems,it is essential to map these heterogeneous datasets into temporally and spatially consistent gridded products.Optimal Interpolation remains the most widely adopted algorithm for the mapping of oceanographic data.Two principal implementations of the optimal interpolation algorithm are commonly employed.The first,known as the basic optimal interpolation,is derived from the theory of optimal estimation and involves computationally intensive matrix operations,posing significant challenges when applied to high-dimensional problems.The second,referred to as the point-wise optimal interpolation,reduces computational complexity through point-wise estimation,thereby circumventing high-dimensional operations;however,this approach results in a substantially higher overall computational cost.In this study,a novel optimal interpolation algorithm is proposed that utilizes the Kronecker product to approximate the background error covariance matrix.This formulation enables the decomposition of high-dimensional matrix operations into smaller,computationally tractable sub-problems,thereby improving the scalability of optimal interpolation for large spatial domains with dense observational coverage.Building upon this framework,a multi-scale optimal interpolation method is further developed to enhance the integration of observational datasets with widely varying spatial resolutions,thereby improving the accuracy and applicability of the resulting gridded products. 展开更多
关键词 oceanic observation mapping optimal interpolation algorithm multi-scale algorithm background error covariance Kronecker product
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Domain semantic mapping of database metasearch engine
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作者 苗广祥 陈向阳 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期357-360,共4页
In order to implement semantic mapping of database metasearch engines, a system is proposed, which uses ontology as the organization form of information and records the new words not appearing in the ontology. When th... In order to implement semantic mapping of database metasearch engines, a system is proposed, which uses ontology as the organization form of information and records the new words not appearing in the ontology. When the new word' s frequency of use exceeds the threshold, it is added into the ontology. Ontology expansion is implemented in this way. The search process supports "and" and "or" Boolean operations accordingly. In order to improve the mapping speed of the system, a memory module is added which can memorize the recent query information of users and automatically learn the user' s query interest during the mapping which can dynamically decide the search order of instances tables. Experiments prove that these measures can obviously reduce the average mapping time. 展开更多
关键词 ONTOLOGY domain mapping database metasearch engine memory module
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Fundamental Theories of Spatial Similarity Relations in Multi-scale Map Spaces 被引量:22
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作者 YAN Haowen 《Chinese Geographical Science》 SCIE CSCD 2010年第1期18-22,共5页
Similarity relation is one of the spatial relations in the community of geographic information science and cartography.It is widely used in the retrieval of spatial databases, the recognition of spatial objects from i... Similarity relation is one of the spatial relations in the community of geographic information science and cartography.It is widely used in the retrieval of spatial databases, the recognition of spatial objects from images, and the description of spatial features on maps.However, little achievements have been made for it by far.In this paper, spatial similarity relation was put forward with the introduction of automated map generalization in the construction of multi-scale map databases;then the definition of spatial similarity relations was presented based on set theory, the concept of spatial similarity degree was given, and the characteristics of spatial similarity were discussed in detail, in-cluding reflexivity, symmetry, non-transitivity, self-similarity in multi-scale spaces, and scale-dependence.Finally a classification system for spatial similarity relations in multi-scale map spaces was addressed.This research may be useful to automated map generalization, spatial similarity retrieval and spatial reasoning. 展开更多
关键词 similarity relation spatial relation multi-scale map spaces
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Formula for calculating spatial similarity degrees between point clouds on multi-scale maps taking map scale change as the only independent variable 被引量:6
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作者 Yang Weifang Yan Haowen Li Jonathan 《Geodesy and Geodynamics》 2015年第2期113-125,共13页
The degree of spatial similarity plays an important role in map generalization, yet there has been no quantitative research into it. To fill this gap, this study first defines map scale change and spatial similarity d... The degree of spatial similarity plays an important role in map generalization, yet there has been no quantitative research into it. To fill this gap, this study first defines map scale change and spatial similarity degree/relation in multi-scale map spaces and then proposes a model for calculating the degree of spatial similarity between a point cloud at one scale and its gener- alized counterpart at another scale. After validation, the new model features 16 points with map scale change as the x coordinate and the degree of spatial similarity as the y coordinate. Finally, using an application for curve fitting, the model achieves an empirical formula that can calculate the degree of spatial similarity using map scale change as the sole independent variable, and vice versa. This formula can be used to automate algorithms for point feature generalization and to determine when to terminate them during the generalization. 展开更多
关键词 Spatial similarity degree map generalization map scale change Point clouds Quantitative description Spatial similarity relations multi-scale map spaces Curve fitting method
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Optimized Convolutional Neural Networks with Multi-Scale Pyramid Feature Integration for Efficient Traffic Light Detection in Intelligent Transportation Systems 被引量:1
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作者 Yahia Said Yahya Alassaf +2 位作者 Refka Ghodhbani Taoufik Saidani Olfa Ben Rhaiem 《Computers, Materials & Continua》 2025年第2期3005-3018,共14页
Transportation systems are experiencing a significant transformation due to the integration of advanced technologies, including artificial intelligence and machine learning. In the context of intelligent transportatio... Transportation systems are experiencing a significant transformation due to the integration of advanced technologies, including artificial intelligence and machine learning. In the context of intelligent transportation systems (ITS) and Advanced Driver Assistance Systems (ADAS), the development of efficient and reliable traffic light detection mechanisms is crucial for enhancing road safety and traffic management. This paper presents an optimized convolutional neural network (CNN) framework designed to detect traffic lights in real-time within complex urban environments. Leveraging multi-scale pyramid feature maps, the proposed model addresses key challenges such as the detection of small, occluded, and low-resolution traffic lights amidst complex backgrounds. The integration of dilated convolutions, Region of Interest (ROI) alignment, and Soft Non-Maximum Suppression (Soft-NMS) further improves detection accuracy and reduces false positives. By optimizing computational efficiency and parameter complexity, the framework is designed to operate seamlessly on embedded systems, ensuring robust performance in real-world applications. Extensive experiments using real-world datasets demonstrate that our model significantly outperforms existing methods, providing a scalable solution for ITS and ADAS applications. This research contributes to the advancement of Artificial Intelligence-driven (AI-driven) pattern recognition in transportation systems and offers a mathematical approach to improving efficiency and safety in logistics and transportation networks. 展开更多
关键词 Intelligent transportation systems(ITS) traffic light detection multi-scale pyramid feature maps advanced driver assistance systems(ADAS) real-time detection AI in transportation
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Methods of 3D map storage based on geo-referenced image database 被引量:1
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作者 YUAN Zhan-liang LI Xun +3 位作者 WANG Jin-ling YUAN Qi-qi XU Dan DIAO Jing-jing 《中国有色金属学会会刊:英文版》 CSCD 2011年第S3期654-658,共5页
In order to store and manage a large amount of ground and indoor image data with high resolution,an integrated data management system needs to be developed.Possible strategies for this purpose were discussed together ... In order to store and manage a large amount of ground and indoor image data with high resolution,an integrated data management system needs to be developed.Possible strategies for this purpose were discussed together with initial test on the newly defined 3D maps.The features of such 3D maps,data organization,key techniques used for the map storage,such as image compression based on wavelet transformation,quadtree index,update and retrieval,were analyzed,with the goals of bringing some profits to the storage and management of the digital data in the visual construction of digital mine,digital city and digital community. 展开更多
关键词 3D map geo-referenced image image database storage technology
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Design of Conceptual Model in Digital Map Database
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作者 ZOU Yijiang 《Geo-Spatial Information Science》 2002年第4期46-49,共4页
The components of map information are analyzed theoretically in this paper,and the map information includes mainly the spatial information,attributive information and temporal characteristics information.Then the digi... The components of map information are analyzed theoretically in this paper,and the map information includes mainly the spatial information,attributive information and temporal characteristics information.Then the digital map entity is defined according to construction characteristics of the map information.Finally,on the basis of the analyses of the construction characteristics of digital map entity and present conceptual model of digital map database,an abstracted conceptual model of digital map database is presented.And the Normal Form theory of relational database is discussed particularly. 展开更多
关键词 digital map database conceptual model
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Establishing a National Ice Database and Developing an Ice Severity Map
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作者 Liu Heyun Zhou Di +2 位作者 Fu Junping Cai minxi (Changsha University of Electric power) Huan Suyi (Huazhong University of Science and Technology) 《Electricity》 2000年第3期46-49,共4页
This paper describes the develop method of an ice database and regional ice seventy maps using information from Storm Data, a national meteorological Center (NMC) Publication and ice observation station. This resource... This paper describes the develop method of an ice database and regional ice seventy maps using information from Storm Data, a national meteorological Center (NMC) Publication and ice observation station. This resource will provide convenient access to ice information for electric utility companies. Using this information, an engineer will be able to identify important characteristics of ice storms for a specific area, when evaluating or designing a power transmission line. Additionally, when developing local design ice load maps, the importance of correlating predicted icing events with historical ice storms makes this information even more valuable for utilities. 展开更多
关键词 ICE ICE SEVERITY map database transmission line.0
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Research on the Mapping Technology of CIM and Relational Database in Power Grid
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作者 赵婉婷 王滨 《科技信息》 2011年第7期222-223,共2页
With the development of electric power industry,the requirement of information sharing and application integration between each application system is salience.To realize the real "sharing information,data mainten... With the development of electric power industry,the requirement of information sharing and application integration between each application system is salience.To realize the real "sharing information,data maintenance uniform",and effectively eliminate "island of information",a standard,open information model of power system should be followed urgently by different systems,and a common data interface should be provided.The Common Information Model(CIM) proposed by standard of IEC-61970 solve the problem effectively.The characteristics of the CIM Model and relational database of power system are analyzed,a mapping method between CIM model based on standard of IEC61970 and relational database is proposed,and corresponding problems between object-oriented model and the relational model are solved flexiblely. 展开更多
关键词 数据库 CIM GIS 地理信息系统
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Coping with Multi-scale Climate Change:Study on the Application of Urban Environmental Climate Maps of Stuttgart,Germany
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作者 ZHANG Qi YANG Xin 《Journal of Landscape Research》 2021年第5期41-46,50,共7页
The development of modern cities has brought about tremendous changes in the climate environment.Faced with complex climate conditions,research on multi-scale climate change in cities is of great significance.The urba... The development of modern cities has brought about tremendous changes in the climate environment.Faced with complex climate conditions,research on multi-scale climate change in cities is of great significance.The urban environmental climate maps and the application of climate atlas tool in Stuttgart,Germany were studied,and the multi-scale application of urban environmental climate maps in Stuttgart,Germany was summarized through the analysis of the pre-planning,current construction situation,and landscape reconstruction of the German"Stuttgart 21"plan case.Besides,other important measures to cope with climate change in German were proposed,and finally multi-scale practical strategies to cope with urban climate and environment were summarized to provide ideas and methods for improving China’s future urban climate environment. 展开更多
关键词 Urban environmental climate maps multi-scale Stuttgart 21 plan Climate coping strategy
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基于MAPublisher高效精细化制图方法研究
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作者 黄臻 王晶 蔡小青 《测绘与空间地理信息》 2026年第2期19-21,共3页
针对面向调研、应急指挥、重大活动策划及政府部门工作决策的省级政务地图保障服务需求,提出了基于MAPublisher高效精细化制图的技术思路及主要实现的技术方法。通过实际生产应用,验证了本文研究的技术方法可行,具有广阔的应用前景。
关键词 mapublisher 快速出图 精细化制图 多尺度地图数据库
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An Approach for Automatically Generating R2RML-Based Direct Mapping from Relational Databases
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作者 Mohamed A.G. Hazber Ruixuan Li +1 位作者 Guandong Xu Khaled M. Alalayah 《国际计算机前沿大会会议论文集》 2016年第1期41-44,共4页
For integrating relational databases (RDBs) into semantic web applications, the W3C RDB2RDF Working Group recommended two approaches, Direct Mapping (DM) and R2RML. The DM provides a set of mapping rules according to ... For integrating relational databases (RDBs) into semantic web applications, the W3C RDB2RDF Working Group recommended two approaches, Direct Mapping (DM) and R2RML. The DM provides a set of mapping rules according to RDB schema, while the R2RML allows users to manually define mappings according to existing target ontology. The major problem to use R2RML is the effort for creating R2RML mapping documents manually. This may lead to appearance of many mistakes in the R2RML documents and requires domain experts. In this paper, we propose and implement an approach to generate an R2RML mapping documents automatically from RDB schema. The R2RML mapping reflects the behavior of the DM specification and allows any R2RML parser to generate a set of RDF triples from relational data.The input of generating approach is DBsInfo class that automatically generated from relational schema. An experimental prototype is developed and shows the effectiveness of our approach algorithms. 展开更多
关键词 RELATIONAL database to RESOURCE DESCRIPTION FRAMEWORK (RDB2RDF) Direct mapping R2RML RELATIONAL database RESOURCE DESCRIPTION FRAMEWORK (RDF)
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基于ArcGIS Geodatabase基础空间数据库设计 被引量:20
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作者 穆荣 张永福 路星 《测绘与空间地理信息》 2007年第3期112-115,共4页
通过对空间数据库管理系统模式的发展进行分析,深入研究了面向对象的空间数据模型——Geodata-base,提出了新的基于ArcGIS的数字地形图空间数据库的分层、编码、属性设计方案。
关键词 数字地形图 空间数据库 空间数据库设计 GEOdatabase
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基于Geodatabase建立数字地质图数据库的方法与实践 被引量:14
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作者 徐翠玲 《测绘科学》 CSCD 北大核心 2008年第3期176-177,186,共3页
本文简要介绍了Geodatabase空间数据模型的特点及优势,列举了创建Geodatabase数据库通用的三种方法,并以1:5万却勒塔格幅地质图为例,重点探讨了用CASE工具建立基于Geodatabase数字地质图数据库的具体过程。研究表明,用这种方法建立地质... 本文简要介绍了Geodatabase空间数据模型的特点及优势,列举了创建Geodatabase数据库通用的三种方法,并以1:5万却勒塔格幅地质图为例,重点探讨了用CASE工具建立基于Geodatabase数字地质图数据库的具体过程。研究表明,用这种方法建立地质图数据库可以将面向对象方法很好地应用于空间数据库的设计中,大大缩短了建库时间,提高了建库效率,并使商用关系型数据库的技术和优势得到充分发挥。 展开更多
关键词 GEOdatabase 数字地质图 数据库 方法与实践
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基于Geodatabase的地理数据库的设计 被引量:7
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作者 杨利兵 陈艳红 刘亚立 《山西建筑》 2007年第25期367-368,共2页
介绍了城市地理空间基础框架,阐述了在数据库设计中对空间实体的逻辑划分,就基于Geodatabase的地理空间数据库的分层设计和属性设计进行了探讨,以实现城市信息资源的整合和共享。
关键词 数据库设计 地理信息系统 数字地形图
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MULTI-RESOLUTION SEAMLESS IMAGE DATABASE 被引量:1
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作者 Wang Mi Gong Jianya Li Deren 《Geo-Spatial Information Science》 2000年第3期52-56,共5页
This paper presents the basic concepts and principles,data structure and high efficient spatial index for multi_resolution image database.The database is characterized by arrangement of multi_resource image data and s... This paper presents the basic concepts and principles,data structure and high efficient spatial index for multi_resolution image database.The database is characterized by arrangement of multi_resource image data and seamless mosaic,distribution_based storage and management,integration with other spatial database software such as GeoStar and GeoGrid developed by Wuhan Technical University of Surveying and Mapping. 展开更多
关键词 multi-scale database SPATIAL databaseS data structure
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Structure design and establishment of database application system for alien species in Shandong Province,China 被引量:1
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作者 GUO Wei-hua LIU Heng +2 位作者 DU Ning ZHANG Xin-shi WANG Ren-qing 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第1期11-16,共6页
This paper presents a case study on structure design and establishment of database application system for alien species in Shandong Province, integrating with Geographic Information System, computer network, and datab... This paper presents a case study on structure design and establishment of database application system for alien species in Shandong Province, integrating with Geographic Information System, computer network, and database technology to the research of alien species. The modules of alien species database, including classified data input, statistics and analysis, species pictures and distribution maps, and out date input, were approached by Visual Studio.net 2003 and Microsoft SQL server 2000. The alien species information contains the information of classification, species distinction characteristics, biological characteristics, original area, distribution area, the entering fashion and route, invasion time, invasion reason, interaction with the endemic species, growth state, danger state and spatial information, i.e. distribution map. Based on the above bases, several models including application, checking, modifying, printing, adding and returning models were developed. Furthermore, through the establishment of index tables and index maps, we can also spatially query the data like picture, text and GIS map data. This research established the technological platform of sharing information about scientific resource of alien species in Shandong Province, offering the basis for the dynamic inquiry of alien species, the warning technology of prevention and the fast reaction system. The database application system possessed the principles of good practicability, friendly user interface and convenient usage. It can supply full and accurate information inquiry services of alien species for the users and provide functions of dynamically managing the database for the administrator. 展开更多
关键词 Alien species database application system Distribution map SQL Server Visual Studio.net Shandong Province
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Disparity estimation for multi-scale multi-sensor fusion
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作者 SUN Guoliang PEI Shanshan +2 位作者 LONG Qian ZHENG Sifa YANG Rui 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期259-274,共16页
The perception module of advanced driver assistance systems plays a vital role.Perception schemes often use a single sensor for data processing and environmental perception or adopt the information processing results ... The perception module of advanced driver assistance systems plays a vital role.Perception schemes often use a single sensor for data processing and environmental perception or adopt the information processing results of various sensors for the fusion of the detection layer.This paper proposes a multi-scale and multi-sensor data fusion strategy in the front end of perception and accomplishes a multi-sensor function disparity map generation scheme.A binocular stereo vision sensor composed of two cameras and a light deterction and ranging(LiDAR)sensor is used to jointly perceive the environment,and a multi-scale fusion scheme is employed to improve the accuracy of the disparity map.This solution not only has the advantages of dense perception of binocular stereo vision sensors but also considers the perception accuracy of LiDAR sensors.Experiments demonstrate that the multi-scale multi-sensor scheme proposed in this paper significantly improves disparity map estimation. 展开更多
关键词 stereo vision light deterction and ranging(LiDAR) multi-sensor fusion multi-scale fusion disparity map
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Investigation and Design of General Seismic Data Model Based on Relational Database
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作者 Meng En Meng Dong-yue +1 位作者 Wang Hon-gwei Zhao Guang-tao 《石油地球物理勘探》 EI CSCD 北大核心 2009年第A02期151-157,共7页
关键词 关系数据库模型 地震数据 模型设计 对象关系映射 数据存储方式 基础结构 数据共享 石油勘探
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