• Korean Journal of Remote Sensing
• /
• v.24 no.2
• /
• pp.141-152
• /
• 2008

The 3D building modeling is one of crucial components in constructing 3D geospatial information. The existing methods for 3D building modeling depend mainly on manual photogrammetric processes, which indeed take great amount of time and efforts. In recent years, many researches on 3D building modeling using aerial LiDAR data have been actively performed to aim at overcoming the limitations of existing 3D building modeling methods. Either techniques with interpolated grid data or data fusion with digital map and images have been investigated in most of existing researches on 3D building modeling with aerial LiDAR data. The paper proposed a method of 3D building modeling with LiDAR data only. Firstly, octree-based segmentation is applied recursively to LiDAR data classified as buildings in 3D space until there are no more LiDAR points to be segmented. Once octree-based segmentation is completed, each segmented patch is thereafter merged together based on its geometric spatial characteristics. Secondly, building model components are created with merged patches. Finally, a 3D building model is generated and composed with building model components. The experimental results with real LiDAR data showed that the proposed method was capable of modeling various types of 3D buildings.

• 한국지구물리탐사학회:학술대회논문집
• /
• 2009.10a
• /
• pp.75-80
• /
• 2009

Despite its flexibility to complex geometry, three-dimensional (3D) electromagnetic(EM) modeling schemes using finite element method (FEM) have been faced to practical limitation due to the resulting large system of equations to be solved. An efficient 3D FEM modeling scheme has been developed, which can adopt either direct or iterative solver depending on the problems. The direct solver PARDISO can reduce the computing time remarkably by incorporating parallel computing on multi-core processor systems, which is appropriate for single frequency multi-source configurations. When limited memory, the iterative solver BiCGSTAB(1) can provide fast and stable convergence. Efficient 3D simulations can be performed by choosing an optimum solver depending on the computing environment and the problems to be solved. This modeling includes various types of controlled-sources and can be exploited as an efficient engine for 3D inversion.

• 한국방재학회:학술대회논문집
• /
• 2007.02a
• /
• pp.418-421
• /
• 2007

It is important to maintain information by application or 3D modeling through the satellite and UAV image which is a real world. The prevention business has recognized the need for accurate 3-D geospatial information around the disaster region to identify objects to 3D modeling. In this paper, we presented an approach to create 3D model and loading, processing the image using GIS techniques, and the digital topographic maps were used for the DEM and the features of the area. The result is a implementation of the simple application that illustrates the objects in 3-D. The presented approach will be used for identifying objects and assisting in regional planning around the airfields.

• The KIPS Transactions:PartB
• /
• v.10B no.2
• /
• pp.157-162
• /
• 2003

In this paper, in-depth considerations are given to various techniques suggested for photographic 3D modelling and possible enhancements of the techniques are discussed. It is found that both the improvement of fundamental matrix estimation techniques and the stereo image rectification processing stage are necessary for more accurate 3D modelling.

• Journal of KIISE:Computer Systems and Theory
• /
• v.30 no.11
• /
• pp.621-628
• /
• 2003

This paper addresses a method of enabling objects in an image to have apparent 3D motion. Many researchers have solved this issue by reconstructing 3D model from several images using image-based modeling techniques, or building a cube-modeled scene from camera calibration using vanishing points. This paper, however, presents the possibility of image-based motion without exact 3D information of scene geometry and camera calibration. The proposed system considers the image plane as a projective plane with respect to a view point and models a 2D frame of a projected 3D object using only lines and points. And a modeled frame refers to its vanishing points as local coordinates when it is transformed.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.8 no.8
• /
• pp.1187-1193
• /
• 2013

In this paper, we present realistic 3D head modeling and facial expression systems. For 3D head modeling, we perform generic model fitting to make individual head shape and texture mapping. To calculate the deformation function in the generic model fitting, we determine correspondence between individual heads and the generic model. Then, we reconstruct the feature points to 3D with simultaneously captured images from calibrated stereo camera. For texture mapping, we project the fitted generic model to image and map the texture in the predefined triangle mesh to generic model. To prevent extracting the wrong texture, we propose a simple method using a modified interpolation function. For generating 3D facial expression, we use the vector muscle based algorithm. For more realistic facial expression, we add the deformation of the skin according to the jaw rotation to basic vector muscle model and apply mass spring model. Finally, several 3D facial expression results are shown at the end of the paper.

• Broadcasting and Media Magazine
• /
• v.26 no.4
• /
• pp.23-39
• /
• 2021

2차원 영상을 3차원 모델 영상으로 변환하는 방식이 다양하게 발전해오고 있다. 딥러닝의 발전 중 특히 GAN의 다양한 연구는 2차원 영상의 생성뿐만 아니라 다양한 3차원 영상의 생성에도 진전을 보였다. 본 고에서는 2차원 영상을 3차원 영상으로 변환하는 연구의 필요성을 바탕으로 관련 연구의 내용과 동향을 분석하였다. 주요 내용으로는 딥러닝 기반의 3차원 객체인식, 2D로부터 3D 변환을 위한 신경망에 대한 연구, 생성적 기법을 적용한 연구, 3D 모델링 도구 등이 포함된다. 관련 연구의 전반적인 흐름을 고려했을 때 향후 3D 모델링의 정교한 표현력 향상, 고속의 고해상도 렌더링, 편리한 온라인 접근성 등을 예상하게 된다. 관련 산업 종사자들에게는 생성시간의 단축을 가져올 수 있고 일반인은 전문적인 3D 기술이 없어도 우수한 3D 모델을 생성하고 활용할 수 있을 것으로 기대한다.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
• /
• 2003.04a
• /
• pp.550-555
• /
• 2003

최근에 Lidar 데이터를 이용한 3차원 위치 정보와 지표면 속성 정보를 취득하는 연구가 많이 진행되고 있다. 높은 위치 정확도, 3차원 데이터 동시 취득, 기존 측정 방식에 비하여 점 데이터 취득의 자동화, 데이터 정확도의 안정성 등으로 인하여 복잡한 지형 및 인공구조물이 존재하는 지역에서 Lidar 데이터의 응용 사례가 많이 나타나고 있으며, 특히 건물 모델링에서 반자동 방식의 디지털 사진측량에 비하여 자동 모델링의 가능성을 보여주고 있다. 일반적으로 Lidar 데이터의 점밀도는 1점/㎡이내이며, 촬영된 스트립을 중복시켜 점밀도를 높이기도 한다. 건물은 크기와 형태가 다양하기 때문에 모델링에 필요한 점밀도를 제시하기는 어렵지만 5점 내외에서 모델링이 가능하다고 알려져 있으며 건물이외에 다른 지형지물에 대한 모델링 연구는 거의 이루어지지 않고 있다. 따라서 본 논문에서는 Lidar 데이터의 점밀도에 따라 지물의 모델링 가능성을 평가하고 효율적인 데이터 취득 방안을 제시하고자 한다.

• Annual Conference of KIPS
• /
• 2017.04a
• /
• pp.966-969
• /
• 2017

3D프린터 기술의 발달로 인해 다가오는 3D프린터의 개인화 시대에 맞추어 개인이 자신이 원하는 출력물을 자유롭게 쉽게 디자인하여 물체를 출력할 수 있도록 도와주는 3D모델링 툴이다. 본 논문에서는 3D프린터 사용에 가장 일반적으로 사용되는 STL파일을 사용자가 별도의 변환과정없이 오브젝트를 바로 STL로 만들어 낼 수 있는 모델링 도구를 제시한다.

• Tunnel and Underground Space
• /
• v.22 no.6
• /
• pp.412-428
• /
• 2012

To achieve mine development, a large amount of data concerned with the geological structure and the ore body had to be investigated and collected through geological survey, drilling and geophysical explorations. In most previous cases, however, the data were usually analyzed two dimensionally and those results showed some limits because of their 2D presentation. Those 2D maps such as geological plane sections or longitudinal sections cause lots of difficulties in understanding the complex geological structure or the feature of ore body in a spatial way. In this study, research area was set on the abandoned Yangyang iron mine in Korea and the Sugaeng ore body within the mine was selected as the research target to design a mine haulage system for reopening. A 3D mine model of this area was tried to be constructed using a 3D modelling software, GEMS. An accurate 3D model including the ore body, the geological structure, the old underground mine drifts and the new mine drifts was constructed under the purpose of reopening of the abandoned iron mine. Especially, mine design for trackless haulage system was conducted. New inclines and drifts were planned and modelled 3 dimensionally considering the utilization of old drifts and shaft. In addition to the 3D modelling, geostatistical technique was adopted to generate a spatial distribution of the ore grade and the rock physical properties. 3D model would be able to contribute in solving problems such as evaluating ore reserves, planning the mine development and additional explorations and changing the development plans, etc.