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The Four Intersection-and-Difference Model for Line-Line Topological Relations

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Geo-Spatial Information Science 2007年第4期10卷 293-298页

作者： DENG Min LI Zhilin LI Guangqiang ZHANG Xuesong department of Surveying and Geo-informatics Central South University Yuelu Mountain Changsha 410083. China

The description of line-line topological relations is still an unsolved issue although much effort has been done. The problem is involved in many practical applications such as spatial query, spatial analysis and cartographic generalization. To develop a sound and effective approach to describe line-line relations, it is first necessary to define the topology of an individual line, i.e., local topology. The concept of connective degree is used for the identification of topological differences in the geometric structure of a line. The general topological definition of a line is given, i.e., endpoints set and interior point set. This definition can be applied to the embedded spaces of different dimensions, whether co-dimension is equal to or larger than zero. On this basis, a generic model called the 4 intersection-and-difference is set up for the description of basic line-line topological relations, upon which a conceptual neighborhood graph is built with consideration of topological distance, it is concluded that the proposed model can represent the property of topological changes, and basic relations between line segments in IR^1 and IR^2.

关键词： topological relations line object topological distance conceptual neighborhood co-dimension

Erosion Vulnerability Assessment of Sperchios River Basin, in East Central Greece—A GIS Based Analysis

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Open Journal of Geology 2017年第5期7卷 621-646页

作者： Nikolaos Stathopoulos Evdoxia Lykoudi Eleni Vasileiou Dimitrios Rozos Dimitrios Dimitrakopoulos department of Geological Sciences School of Mining Engineering and Metallurgy National Technical University of Athens Athens Greece department of Hydrogeological Studies Direction of Studies and Development of Mines Public Power Corporation of Greece Athens Greece

One of the most important natural processes, with significant environmental impacts, is soil erosion. The aim of this paper is to evaluate and assess the erosion vulnerability of the geological formations constituting Sperchios River basin, in Eastern Central Greece, as well as to distinguish and locate the areas of such risk and estimate it. The developed methodology in this paper is based on Multi-Criteria Evaluation (MCE), with the implementation of Weighted cartographic Overlay (WCO) technique in Geographic Information Systems (GIS) environment. By applying this method, an attempt was made to combine a set of factors, such as geological-hydrogeological characteristics, morphological slopes and hydrographic texture (causative factors of the phenomenon) along with rainfall (triggering factor) and land cover/use (competitive factor). The weighted combination of these factors defines the vulnerability of the formations in the area of interest. The main results of the methodology are two thematic maps of erosion vulnerability of Sperchios basin’s formations, one that does not include land use/cover factor and one with current existing conditions of the basin (co-evaluating land use/cover). In the first case, 36% of the basin surface undergoes high erosion vulnerability, while 53% present medium vulnerability. These percentages reduced significantly in the second case (3% is the high erosion vulnerability category and 38% the medium one), fact that proves the importance of vegetation in erosion restriction and protection of the geological formations consisting the Sperchios River basin.

关键词： Erosion Vulnerability Sperchios River Basin Geographical Information Systems Multi-Criteria Evaluation

Geographical Factor as a Basis for Research of State BordersmAn Example of Georgia

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Journal of Earth Science and Engineering 2013年第10期3卷 701-713页

作者： Dali A. Nikolaishvili Revaz Sh. Tolordava Faculty of Exact and Natural Sciences Department of Geography Tbilisi State University Tbilisi 0128 Georgia Faculty of Exact and Natural Sciences Department of Natural Science and Healthcate Sokhumi State University Tbilisi 0128Georgia

The work deals with analysis of geographical factor as one of the main factor determining the historical change of a border on the example of Georgia. The research was conducted in two main directions： the evaluation of historical transformations of state borders of Georgia throughout of XIX-XX centuries and identification the leading geographical factors. Special emphasis has been made on geographical and cartometric analysis of modern state border of Georgia. In order to identify the historical transformations of state border that have used different methods as well as GIS-technologies, the research is based on the historical, cartographical and statistical data. On the base of a lot of cartographic sources, it is concluded that the borderline in modem topographic maps is often plotted by ignoring the international practice related to plotting the state borders across the physical-geographical objects. This is why the geographical factor seems important in the historical transformations of the state border creating similarly a negative perspective in the future. The main results of research are：（1） classification of geographical factors causing the transformations of the state borders; （2） Evaluation of sensitivity of state border; and （3） creation of DB of the state border of Georgia, allowing continuing the studies in the future.

关键词： State Border types of Sate border cartometric-geographical analysis geographical factor Georgia.

Altimetry Quality of SRTM and ASTER GDEM Products for Areas with Different Reliefs

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Journal of Geographic Information System 2019年第6期11卷 683-714页

作者： Vivian da Silva Celestino Reginato department of Civil Engineering Federal University of Santa Catarina (UFSC) Florianópolis Brazil

Hydroelectric power plants cause impacts that are usually estimated by an indicator, the hydroelectric power generation per hectare of flooded area. And, although entrepreneurs use quality-declared cartographic bases to comply with the standards, at the project stages of a hydroelectric plant it is not a priori determined whether the altimetry tolerance of such bases is sufficient to ensure that the impacts will not increase, which in the project consolidation becomes a huge problem. This work aims to define the altimetry quality of SRTM Digital Elevation Models (DEM) and ASTER GDEM and whether they are a priori sufficient to simulate the flood level of hydroelectric power plants in different reliefs. To accomplish this objective, a morphological method of assessment of the DEM quality was developed, through Geographic Information Systems (GIS), so that the altimetry information generated by the models and field surveys, when compared, would show their actual differences also in relation to their areas. To this end, two study areas were used: one with a slightly undulated relief and the other with undulated relief. To validate the models, quality assessments were carried out: based on points, according to the Brazilian Map Accuracy Standard (MAS) and STANAG 2215;and based on surfaces, according to Article 500 of the Brazilian Civil Code and the morphological method. At the end, practical applications relating to the M&P indicator and hydroelectric power plants projects were also carried out. The results presented demonstrate that the quality of an SRTM DEM when used in undulating or gently undulating reliefs can be used up to 1:80,000 scale. Already for DEM ASTER under the same conditions, it is possible to use on the scale 1:100,000. In DEM SRTM and DEM ASTER, after removing the systematic error (−7.3 m) and (−6.2 m), respectively, the quality between 65% and 79% is verified for DEM SRTM and 53%, and 68% for DEM ASTER for common areas in flood level sim

关键词： Altimetry Quality Geographic Information Systems (GIS) Remote Sensing Digital Elevation Model (DEM) Morphology

Updating Traditional 1/50,000 Topographic Maps Using Crowd-Sourced Geodata and Free Sources Satellite Images

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Journal of Geographic Information System 2021年第2期13卷 274-286页

作者： Atef Belhaj Ali Mohamed Hafedh Hamza department of Geography and GIS Faculty of Arts and Humanities King Abdulaziz University Jeddah KSA

This paper addresses how open geodata and crowd-sourced geodata, and the open geoportals might be integrated with the mainstream surveying and mapping practices to update traditional topomaps quickly and inexpensively, that might be otherwise impossible to do it due to economic and logistic situations. The abundant geographic data on the internet could be used to update topographic maps while avoiding the time-consuming nature of the traditional method. To be able to use them, it is necessary to measure and quantify the quality of these data, as well as to verify their credibility, in order to incorporate them into official topographic maps. The proposed approach takes advantage of neocartography, and it’s not about further developing a new approaches, but looking differently at how data is collected, assembled controlled and been used for updating topomaps. At the beginning, the methodology used about how open geodata and crowd-sourced geodata involved in collecting, simplifying, generalizing, controlling and generating useful cartographic information that complement traditional and conventional counterparts is presented. This methodology was applied on a 1/50,000 topomap located in the north of Jeddah city (western region of Saudi Arabia), and we have demonstrated that by using this type of data, it is possible to update topographic maps quickly and at a lower cost while maintaining cartographic precision and accuracy standards.

关键词： Topomaps Map Update Open Geodata Crowed Sourced Geodata Open Street Map (OSM) Geodata Quality Hausdorff Distance

Public Use and Landscape Analysis in the Serra da Canastra National Park, Brazil: A Geospatial Approach

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Natural Resources 2016年第2期7卷 93-101页

作者： Marcos Cicarini Hott Luiz Otávio Moras Filho Marco Aurélio Leite Fontes Aline Aparecida Silva Pereira Cláudia de Oliveira Gonçalves Nogueira Luis Marcelo Tavares de Carvalho Luís Antônio Coimbra Borges João Cesar de Resende Mauro Antonio Homem Antunes department of Forest Sciences Federal University of Lavras Lavras Brazil Brazilian Agricultural Research Corporation—Embrapa Juiz de Fora Brazil department of Engineering Federal Rural University of Rio de Janeiro Seropédica Brazil

The Conservation Units (CU) were created to protect natural environments from growing degradation and to impede the expansion of urbanization and agricultural crops. The Serra da Canastra National Park, established to protect the headwaters of the S?o Francisco River and other places of scenic and ecological interest, is extensively visited due to its many tourist attractions, such as waterfalls, fauna and flora. An analysis of the park’s geography is needed to assess the risk involved in and its suitability for public use due to its territorial extension and environmental complexities. Thus, this study aimed to investigate the background of issues of interest to CU management. Additionally, we used high-resolution RapidEye imagery, altimetry and database of park infrastructure to build geospatial database and estimate classes of suitability for and risk in public use through GIS tools. The resulting cartographic data can support the planning of policies concerning the landscape and park’s territorial management.

关键词： Conservation Units Environment GIS RapidEye Imagery

A Collaborative Simplification Method for Multiple Coastlines Based on the Hierarchical Triangulation Network Partition

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Journal of Geodesy and Geoinformation Science 2020年第2期3卷 93-104页

作者： Lihua ZHANG Lulu TANG Shuaidong JIA Zeyuan DAI department of Military Oceanography and Hydrography&Cartography Dalian Naval AcademyDalian 116018China

For the current automatic coastline generalization method,only one-line element is considered separately,but the relationship between the nearby elements is not effectively considered.A synergistic simplification method for multiple coastlines based on the hierarchical triangulation network partition(HTNP)is proposed in this ***,the constrained Delaunay triangulation is constructed to partition the regions that can be ***,a hierarchical binary tree model to structure the morphological characteristics of the above several coastlines and the spatial proximity between different coastlines is ***,the small curved and curved invisible parts of the coastline are deleted according to the visual constraints,and the narrow part between the coastline itself or the different coastlines is exaggerated appropriately,and the automatic simplification of the coastline is *** experimental results show that:①Relationships between the different coastlines are considered,and the shortcomings of considering the coastline separately are overcome;②Under the condition of the multiple coastlines in complex sea areas,the problem of collaborative simplification is solved,the quality of the coastlines are improved obviously,and the proposed method can be applied into more types of coastlines.

关键词： cartographic generalization coastline simplification hierarchy relationship synergistic simplification

Landfill Siting Evaluation Using GIS and Multi-Criteria Decision-Making Method: A Case Study: Dammam Municipal Solid Waste Landfill

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Journal of Geographic Information System 2021年第4期13卷 508-522页

作者： Nora Al Khaldi Firdos Almadani Sara Ouerghi department of Geography and GIS Faculty of Arts & Humanities King Abdulaziz University Jeddah Saudi Arabia

Waste landfills are a prominent global issue that does not concern a country without the other because of its long-term effects especially in the environmental aspect. As these pose an environmental threat to water, air and soil;and directly affect human life and health. Accordingly, this research uses the integration of Geographic Information Systems (GIS) and Multi-Criteria Decision-Making (MCDM) approaches to assess the location of the municipal solid waste dump in Dammam, which was established in (2000AD) twenty years ago, due to the lack of recent studies assessing the current status of the landfill and whether it is in a suitable location and keeps pace with the population and urbanization increase in the region. For this purpose, the researchers are using the tools and techniques of GIS to evaluate eight criteria on the study area. The required standards were directed to the landfill site and transformed into maps that represent the most important economic, social, environmental, geological, geomorphological and Public Acceptance standards. These standards have been processed using the tools of spatial and statistical analyses. Analytic Hierarchy Process (AHP) is implemented in geographical information system for building the suitable cartographic model, and thus allowed to determine the suitable degree of Dammam municipal solid waste landfill site in light of the study criteria. The study concluded that the current landfill site achieves a good degree of suitability, as it achieved 63% measured against the quality standards set by the study, and that the current landfill site conforms to most of the criteria in this study to a good degree. But it violates two standards, which are distance from wells standard and distance between landfill and the center of waste generation standard.

关键词： Landfill Site Criteria Weights GIS Analytic Hierarchy Process (AHP)

Evaluation of the Use of Inertial Platform for the Generation of Cartography

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Journal of Civil Engineering and Architecture 2014年第9期8卷 1204-1210页

作者： Luis Antonio de Lima Diogenes Cortijo Costa Jorge Luiz Alves Trabanco Maria Teresa Francoso Technical department Fototerra Atividades de Aerolevantamento Ltda (Fototerra Aerial Survey Activities Ltd.) San Paulo 03337-000 Brazil department of Geotechnics and Transportation The State University of Campinas San Paulo 13083-070 Brazil

This study aims to analyze the quality of positioning orthophoto generated through the technique of direct georeferencing using metric digital camera system coupled to the laser system, and both systems were aided inertial navigation platform. For this, we compared the coordinates obtained in 16 control points collected in the field with dual-frequency GNSS （global navigation satellite system） receiver with those obtained in the orthophoto, flight conducted in June 2009 on the campus of the State University of Campinas--UNICAMP, using a medium format digital camera and laser system, with which we obtained images with a spatial resolution of 0.15 m. Taking into account the pattern accuracy cartographic used in Brazil, it is concluded that the products produced have a standard accuracy ＂A＂ to 1：2,000 scale, which represents the best quality level, both for planimetric as for altimetry, and that the procedure reached results consistent with cartographic products in 1：2,000 scale, representing a reduction of steps in the mapping process, necessary for the preparation of cartographic databases with reduction of time for preparation of design basis large civil engineering projects, such as roads, railways, studies of urban road systems, power plants and other infrastructure systems needed to develop the country.

关键词： Orthophotos photogrammetry GNSS.