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Representation of three-dimensional mass distribution of the Earth's interior by biorthogonal series and its use for studying internal structure of the planet

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Geodesy and Geodynamics 2024年第3期15卷 264-275页

作者： Mykhailo Fys Mariana Yurkiv Andrii Brydun Andrii Sohor department of cartography and Geospatial Modelling Lviv Polytechnic National UniversityLviv 79013Ukraine

This paper utilizes the mathematical concept of approximation within an ellipsoid from a single viewpoint to present the spatial mass distribution function of the Earth's interior and its internal *** primary focus lies in constructing the volume distribution of masses in the planet's interior, with the expansion coefficients being linear combinations of the Stokes constants. Several possible approaches are suggested for determining accurately these coefficients employing three-dimensional(biorthogonal)polynomials. By expressing the mass distribution function of the Earth's interior and its internal potential as a series, an algorithm is introduced for the calculation of gravitational energy. It allows us to estimate fluctuations in gravitational energy. The implementation of this algorithm offers the means of establishing the extent to which the Earth deviates from a state of hydrostatic equilibrium as a celestial *** to the aforementioned method, calculations have been conducted to validate its effectiveness and reliability. This example is given as an illustration of a given method for studying the internal structure of planets.

关键词： Mass distribution function Potential Stokes constants Biorthogonal polynomials

Selected issues of cartographic communication optimization for emergency centers

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International Journal of Digital Earth 2010年第4期3卷 316-339页

作者： Karel Staněk Lucie Friedmannová Petr Kubıcek Milan Konecný Laboratory on Geoinformatics and cartography Department of GeographyFaculty of ScienceMasaryk UniversityBrnoCzech Republic

Cartographic communication and support within emergency management(EM)are complicated issues with changing demands according to the incident extent and phase of the EM *** in mind the specifics of each purpose,it is obvious that spatial data used for maps preparation and production must be differently visualized even for the same type of emergency incident(traffic accident,fire,and natural disaster).Context-based cartography is a promising methodology to deal with the changing demands of an operational EM *** overview of cartographic communication is presented within the context of an operational EM center,activities of particular actors,and map use supporting the incident *** authors of the paper respond to a series of questions,for example:what is the current cartographic support of operational EM in the Czech Republic in Digital Earth conditions?What possibilities are there to improve the cartographic communication?How can contextual cartographic services be implemented in a Web environment and how can the usability of results be tested?The paper gives several examples of the usage of cartographic technologies in map creation for various emergency situations.

关键词： map use cartographic communication context-based cartography Digital Earth operational emergency management

Normalized evaluation of the performance,capacity and availability of catalogue services:a pilot study based on INfrastruture for SPatial InfoRmation in Europe

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International Journal of Digital Earth 2016年第4期9卷 325-341页

作者： Tomáš Řezníka Radoslav Chudý Eva Mičietová department of Geography Masaryk UniversityBrnoThe Czech Republic department of cartography Geoinformatics and Remote SensingComenius UniversityBratislavaThe Slovak Republic

Geographic information has a great potential to be re-used when supported by mechanisms for its *** all,the quality of a catalogue service is the key feature supporting users in the discovery *** far,there have been in existence various methodologies dealing with the normalized evaluation of quality with respect to catalogue *** biggest weakness seems to be in the depth of quality testing,*** influences are beyond the scope of evaluation of these methodologies with respect to quality in catalogue *** this study,the quality of 45 catalogue services across Europe was verified with the proposed normalized evaluation methodology originating from documents within the INfrastruture for SPatial InfoRmation in Europe(INSPIRE)*** paper discusses the(statistical)influence of factors that may significantly change the results of catalogue service *** proposals for improving the existing INSPIRE normalized evaluation procedure are applicable for any spatial data infrastructure and/or Digital Earth component using the Open Geospatial Consortium Catalogue Service for the Web as a basis.

关键词： metadata quality evaluation spatial data infrastructures INSPIRE Catalogue Service for the Web

A procedural footprint enhancement of global topographic surface with multiple levels of detail

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International Journal of Digital Earth 2020年第4期13卷 527-545页

作者： Lukáš Brůha Jan Kolář Faculty of Science Department of Applied Geoinformatics and CartographyCharles University in PraguePragueCzech Republic Grifinor Project CopenhagenDenmark

Virtual globes are technologies for visual navigation through a threedimensional,multi-resolution model of the entire *** representations used in virtual globes,however,lack geometric flexibility at high-resolution levels of the planet-wide terrain *** is a problem especially if boundaries between individual geospatial features and the terrain are important.A novel integration of individual polygonal boundaries with a specific multi-resolution representation of the planet-wide terrain is developed in this *** the preparation stage,the integration relies on an original simplification algorithm applied to the polygonal boundaries between geospatial features and the *** output is a multiple level-of-detail(LOD)geometry,which can be combined with a known multi-LOD representation of the terrain that uses run-time *** data representation is suitable for storage in existing database systems,avoids any data redundancy across LODs,and is even independent of the subdivision schema that partitions the planet’s surface for the sake of dealing with *** runtime,a novel reconstruction algorithm stitches geometric parts from different LODs together in a manner that augments the multi-LOD representation of the *** a certain proximity range from a given position,the method reconstructs a scene that preserves topological relations between the boundaries of geospatial features with the *** method also guarantees that certain nearest proximity to the given position consists of the best geometries that correspond to the original *** properties of the method close up the gap between a mere exploratory visualization of static,pre-generated models and the models supporting geospatial analysis,which is deemed crucial for applications in Geographic Information Systems,Building Information Modelling and other software industries.A prototype implementation and experiment results that prove this method are also prese

关键词： Feature-based topography multiple level-of-detail procedural modeling vector data organization geometry reconstruction

A block-based selection method for road network generalization

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International Journal of Digital Earth 2011年第2期4卷 133-153页

作者： F.Gulgen T.Gokgoz Geomatics Engineering department Cartography DivisionYıldız Technical UniversityDavutpas¸a Campus34210 EsenlerIstanbulTurkey

When road symbols are shown in a size proportionate to the reduced scale,several problems of legibility may arise concerning the urban *** the method proposed in this paper,in order to overcome these problems,urban block areas are enlarged through amalgamation and the intervening roads in the amalgams are *** method includes two new approaches for computation of threshold used in determination of important roads based on the connectivity measure,and for definition of minimum block space and area requirements based on graphic limits.A block life cycle was designed for amalgamation of *** the amalgamation process,a new algorithm was *** experimental testing indicates that important roads and the roads surrounding the urban area have been preserved.A simpler and more legible road network has been *** method can be described as a more holistic approach as the buildings are taken into *** problems arising in the experimental testing indicate that the cartographic selection/elimination process is not sufficient by itself for road network generalization,which can be assumed as one of the integral parts of Digital *** well as the selection/elimination,processes such as displacement and caricaturizing are also needed.

关键词： GIS cartographic generalization selection/elimination road network Digital Earth

Integrated universal soil loss equation (USLE) and Geographical Information System (GIS) for soil erosion estimation in A Sap basin:Central Vietnam

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International Soil and Water Conservation Research 2018年第2期6卷 99-110页

作者： Tung Gia Pham Jan Degener Martin Kappas cartography GIS and Remote Sensing DepartmentGottingen UniversityGermany University of Agriculture and Forestry Hue UniversityVietnam

Central Vietnam is very susceptible to soil erosion due to its complicated terrain and heavy rainfall. The objective of this study was to quantify soil erosion in the A Sap river basin, A Luoi district, Thua Thien Hue Province, Vietnam, using the Universal Soil Loss Equation (USLE) and Geographical Informa-tion System (GIS). The results showed that 34% of land area lost accumulated to 10 t ha-1 year-1 while 47% of the total area lost less than 1 t ha-1 year-1. Natural forest land lost the most with an average of about 19 t ha-1 year-1, followed by plantation forest with approximately 7 t ha-1 year-1 and other agricultural lands at 3.70 and 1.45 t ha-1 year-1 for yearly crops and paddy rice, respectively. Soil erosion was most sensitive to the topographic factor (LS), followed by the practice support factor (P), soil erodibility factor (K), cropping management (C), and the rainfall erosivity factor (R). Implications are that changes to the cultivated calendar and implementing intercropping are effective ways to prevent soil erosion in cultivated lands. Furthermore, introducing broad leaves trees for mountainous areas in A Sap basin was the most effective practice in reducing soil erosion. The study also pointed out that the combination of available data sources used with the USLE and GIS technology is a viable option to cal-culate soil erosion in Central Vietnam, which would allow targeted attention toward a solution is to reduce future soil erosion.

关键词： Central Vietnam GIS Soil erosion USLE

Virtual representations of antique globes-new ways of touching the untouchable

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International Journal of Digital Earth 2008年第1期1卷 107-118,I0007页

作者： F.Hruby A.Riedl H.Tomberger department of Geography and Regional Research Cartography and GeoinformationUniversity of ViennaUniversita tsstrasse 71010 ViennaAustria

The starting point of this paper is the idea that a comprehensive understanding of the earth and its systems calls for consideration of bygone views of the *** facsimiles of antique globes in the form of digital globes provides a new opportunity to make such bygone world views accessible to a wide scientific ***,up to now,little practical experience in applying digital technology on globes has been *** these attempts by thorough synopsis,this article deduces a comprehensive approach on virtual representations of antique globes that can be described by the superordinate concept of virtual *** concept comprises facilities of data acquisition of the original globe,ways of visualising the digitised globe and its final cartographic *** that arise from this procedure are exemplified through both virtual hyperglobes and tactile *** findings on a 16th century earth globe are encouraging results of the presented virtual representation approach,which may offer a sustainable visualisation platform of interdisciplinary research.

关键词： 3D facsimile digital globe hyperglobe 3D visualisation digital restoration

Visualization of geologic geospatial datasets through X3D in the frame of WebGIS

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International Journal of Digital Earth 2013年第5期6卷 483-503页

作者： Frederik von Reumont Jamal Jokar Arsanjani Andreas Riedl department of Geography and Regional Research Cartography and GeoinformationUniversity of ViennaViennaAustria Geography and its Didactics University of Cologne50931CologneGermany

3D geo spatial data have become the ***,to view the data,usually expert software is required,which have up to now hindered the wide spread use of 3D scenes for the display of geological *** internet real time 3D rendering framework X3D is assessed regarding its suitability for building a geological GIS on the *** important for geological data,3D rendering enhances the intuitive grasp of the data and enables the user to interactively explore *** is often necessary to find a solution to distribute this data to a wide range of interested parties,experts and non-experts *** to the nature of 3D data,the best technique to display geo-data,the modeling of objects and unresolved issues have to be taken into *** internet is the apparent tool for the public distribution and visualization of 3D data and it was found that through the open ISO-standardized format X3D it offers a multitude of possibilities.A 3D geological interactive map was created with these prerequisites to identify challenges and possibilities through this *** was found that the use of lead to satisfactory results,that could probably not have been achieved with another technology.

关键词： webGIS geology X3D interactive map 3D visualization internet x3dom virtual reality

Measuring user preferences and behaviour in a topographic immersive virtual environment(TopoIVE)of 2D and 3D urban topographic data

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International Journal of Digital Earth 2021年第12期14卷 1835-1867页

作者： Łukasz Halik Alexander J.Kent department of cartography and Geomatics Adam Mickiewicz UniversityPoznańPoland School of Psychology and Life Sciences Canterbury Christ Church UniversityCanterburyUK

This paper investigates user preferences and behaviour associated with 2D and 3D modes of urban representation within a novel Topographic Immersive Virtual Environment(TopoIVE)created from official 1:10,000 *** participants were divided into two groups:the first were given a navigational task within a simulated city and the second were given the freedom to explore it.A Head-Mounted Display(HMD)Virtual Reality(VR)app allowed participants to switch between 2D and 3D representations of buildings with a remote controller and their use of these modes during the experiment was *** performed mental rotation tests before entering the TopoIVE and were interviewed afterwards about their experiences using the *** results indicate that participants preferred the 3D mode of representation overall,although preference for the 2D mode was slightly higher amongst those undertaking the navigational task,and reveal that different wayfinding solutions were adopted by participants according to their ***,the findings suggest that users exploit different aspects of 2D and 3D modes of visualization in their wayfinding strategy,regardless of their *** potential to combine the functionality of 2D and 3D modes therefore offers substantial opportunities for the development of immersive virtual reality products derived from topographic datasets.

关键词： Virtual reality(VR) immersive virtual environment(IVE) 2D versus 3D wayfinding topographic data