• The KIPS Transactions:PartD
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• v.10D no.2
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• pp.211-220
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• 2003

As Geographic Information Systems represent three dimensional topological information, The Systems provide accurate and delicate services for users. In order to execute three dimensional topological operations, a dimensional transformation and heterogeneous spatial models should be used. However, the existing systems that use the dimensional transformation and the heterogeneous models, is not only difficult to operate the spatial operators, but also happened to support non-interoperability. Therefore, in order to solve the problems, we proposed three dimensional spatial object models that supported two dimensional object models and implemented them to show validity of the proposed models. When designing the three dimensional topological operators, we used 3DE-9IM which extended DE-9IM to support three dimensional concepts, and implemented operators on the component environment with object oriented concepts. The proposed three dimensional spatial object models and topological operators can support interoperability between systems, and execute spatial queries efficiently on three dimensional spatial objects.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.10a
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• pp.615-618
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• 2001

본 논문은 기존의 3D 게임 엔진에 실시간으로 상호 작용이 가능하고 3D MMORPG(Massive Multi-play Online Role flaying Game) 게임에 적합한 가상 공간을 표현하기 위한 필요한 기술을 분석하고 이를 활용하려 한다. 기존의 머드 게임에 3 차원 기술을 적용하고, 3 차원 물체를 모델링 하는데 있어서 메쉬나 버텍스, 혹은 폴리곤으로 사실적인 지형 처리와 렌드링 속도 향상을 위하여 3 차원 개체의 폴리곤을 동적으로 생성시키고 가시성 판단이나 충돌 검출을 위한 방법으로 Height field 처리 기법과 거리에 변화에 따라 다르게 모델링 된 데이터를 선택적으로 사용하는 CLOD(Continuous Level of Detail) 처리 기법과 입체 컬링 방법으로 옥트리를 이용하여 가상공간을 분해하기 위한 자료 구조로 사용한다. 거리의 변화에 따라 지형을 표현하는 vertex 들을 병합 또는 삭제함으로써 그 표현의 정도를 동적으로 달리 할 수 있는 CLOD 를 이용하여 카메라의 위치와 방향에 따라 적절한 폴리곤을 생성해 낼 수 있다. 본 논문은 기존의 3 차원 공간을 표현하기 위하여 사용되고 있는 옥트리 구조를 이용하여 공간을 분할하고, 이를 세부 수준으로 나누어 처리하기 위한 LOD(Level of Detail)와 CLOD 개념을 이용하여 외부지형을 폴리곤으로 표현하는 방법에 대한 처리 기법과 가시성 판단이나 충돌 검출을 위한 방법을 제시하려 한다.

• 한국지형공간정보학회:학술대회논문집
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• 1995.10a
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• pp.25-62
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• 1995

• Journal of Korea Multimedia Society
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• v.9 no.8
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• pp.950-962
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• 2006

Recently, there have been increased many 3 dimensional graphic applications in Internet. Thus, a growing number of methods have been proposed for retrieving 3-D graphic data using their 3D features such as color, texture, shape, and spacial relations. However, few researches focus on 3D graphic modeling and database storage techniques. In this paper, we introduce a system that can store 3D graphics data modeled by XML-based 3D graphics markup language, 3DGML, and support content-based retrievals on 3D data by using SQL. We also present a mapping technique of 3DGML to relational database. The mapping process includes the extraction of semantic information from 3DGML and translate it into relational format. Finally, we show examples of SQL queries which use the 3D information contained in a 3D scene such as objects, 3D features, descriptions and scene-object component hierarchy.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.4
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• pp.141-149
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• 2010

Three-dimensional geo-spatial information is important for the efficient use and management of the country and the three-dimensional expression and analysis of urban projects, such as urban plans devised by local governments and urban management. Thanks to the revitalization of the geo-spatial information service industry, it is now being variously used not only in public but also private areas. For the creation of high-guiltily three-dimensional geo-spatial information, emphasis should be placed on not only the quality of the source image and three-dimensional geo-spatial model but also the level of visualization, such as level of detail and texturing. However, in the case of existing three-dimensional geo-spatial information, its establishment process is complicated and its data are not updated frequently enough, as it uses ready-created digital maps. In addition, as it uses Ortho Images, the images exist Relief displacement. As a result, the visibility is low and the three-dimensional models of artificial features are simplified to reach LoD between 2 and 3, making the images look less realistic. Therefore, this paper, analyzed the quality of three-dimensional geo-spatial information created using the three-dimensional modeling technique were applied using Digital photogrammetry technique, using digital aerial photo images by an existing large-format digital camera and multi-looking camera. The analysis of the accuracy of visualization information of three-dimensional models showed that the source image alone, without other visualization information, secured the accuracy of 84% or more and that the establishment of three-dimensional spatial information carried out simultaneously with filming made it easier to gain the latest data. The analysis of the location accuracy of true Ortho images used in the work process showed that the location accuracy was better than the allowable horizontal position accuracy of 1:1,000 digital maps.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.2 s.29
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• pp.37-42
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• 2004

The purpose of this study is not only preserving and restoring our nation's precious cultural inheritances transmitted for half millennia but informing the world of them. This study also aims recognizing the necessity of transmitting them to prosperity, constructing three-dimensional database by using a photogrammetry and VRML method and utilizing basic data of treasure exhibition with the progress of exhibition technique development on cyber space. Therefore, in this study, I suggest three dimensional modeling method that acquire three dimensional database about cultural properties through photogrammetry method which can acquire three-dimensional coordinates with easy and can express various color and stuff-feeling by using VRML.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.3 s.33
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• pp.25-32
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• 2005

This paper presents a method for point-based 3D building reconstruction using Lidar data and digital map. The proposed method consists of three processes: extraction of building roof points, identification of roof types, and 3D building reconstruction. After extracting points inside the polygon of building, the ground surface, wall and tree points among the extracted points are removed through the filtering process. The filtered points are then fitted into the flat plane using ODR(Orthogonal Distance Regression) in the first place. If the fitting error is within the predefined threshold, the surface is classified as a flat roof. Otherwise, the surface is fitted and classified into a gable or arch roof through RMSE analysis. Experimental results showed that the proposed method classified successfully three different types of roof and that the fusion of LIDAR data and digital map could be a feasible method of modeling 3D building reconstruction.

• Proceedings of the Korean Information Science Society Conference
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• 2002.04b
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• pp.73-75
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• 2002

PDB에서 제공하는 단백질 3차원 고분자결정 구조에 대한 플랫파일은 인자들의 좌표, 서열정보, 실험정보 및 참조 정보가 포함된다. 이러한 정보를 포함하고 있는 플랫파일로부터 필수적인 구조정보 및 서열정보 등의 효율적인 검색을 위해서는 이러한 데이터를 추출하여 데이터베이스 구축이 요구되며 이 때 단백질 구조 및 서열 정보와 실험 및 탐조 정보의 관계에 대한 모델링이 중요하다. 따라서 이 논문에서는 PDB에서 제공하는 플랫파일들의 엔트리들을 분석하고 3차원 공간 객체의 기하적 특성을 갖는 단백질 3차 구조를 공간객체로 표현하고 공간객체 모델을 적용하여 모델링한다. 이렇게 함으로써 단백질 3차 구조 분자를 구성하는 인자 및 구조 정보 검색이 가능하며 위상 및 기하 연산자글 이용하여 단백질 구조 분석에 활용할 수 있다.

• Journal of Korean Society for Geospatial Information Science
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• v.2 no.2 s.4
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• pp.99-108
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• 1994

In this thesis, we propose the 3D terrain modelling method for the better understanding of the geographic information. The process of 3D terrain medelling consists of three steps. The first step is to obtain real-world data from satellite images and stored in the form of DEM(Digital Elevation Model). The second one is to extract the meaningful data from DEM data based on LOD(Level Of Detail). And the third is to construct the 3D surface by TIN(Triangulated Irregular Network) with the extracted meaingful data. The proposed dynamic TIN reconstruction algorithm locally reconstruct the existed TIN model with the additional a new point. In this way, we can construct the TIN with the reduced time and can simulated 3D terrain model in real time.

• Journal of Energy Engineering
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• v.22 no.2
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• pp.156-168
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• 2013

Drilling expedition #1 in 2007 and drilling expedition #2 in 2010 were performed for gas hydrate resources evaluation and optimal site selection of pilot test in Ulleung basin, East Sea, Korea. This study presents to build the 3D spatial distribution models using the estimated sedimentary facies, porosity, and gas hydrate saturation derived by well logs and core analysis data from UBGH1-4, UBGH1-9, UBGH1-10, UBGH1-14, UBGH2-2-1, UBGH2-2-2, UBGH2-6, UBGH2-9, UBGH2-10 and UBGH2-11. The objective of 3D spatial distribution modeling is to build a geological representation of the gas hydrate-bearing sediment that honors the heterogeneity in 3D grid scale. The facies modeling is populating sedimentary facies into a geological grid using sequential indicator simulation. The porosity and gas hydrate saturation modeling used sequential Gaussian simulation to populate properties stochastically into grid cells.