• 지적과 국토정보
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• 제45권1호
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• pp.193-205
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• 2015

입체공간에 대한 이용이 증가하면서 기존의 2차원 지적으로는 입체공간에 대한 정보를 관리하는데 한계가 있어 입체공간의 물리적 현황 및 사용권에 대한 정보를 등록 관리할 수 있는 3D 지적이 요구되고 있다. 이번 연구는 입체공간의 이용 현황 분석을 통해 3D 지적에 포함될 수 있는 데이터의 범위를 설정하고, 국제표준인 토지행정도메인모델(LADM)을 기반으로 3D 지적을 이해할 수 있는 개념모델을 설계함으로써 3D 지적시스템의 개발을 위한 기반을 마련하고자 한다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2005년도 춘계공동학술대회 발표논문
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• pp.848-853
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• 2005

3D geometric modeling of an object of interest has been intensively investigated in many fields including CAD/CAM and computer graphics. Traditionally, CAD and geometric modeling tools are widely used to create geometric models that have nearly the same shape of 3D real objects or satisfy designers intent. Recently, with the help of the reverse engineering (RE) technology, we can easily acquire 3D point data from the objects and create 3D geometric models that perfectly fit the scanned data more easily and fast. In this paper, we present 3D geometric model generation based on a stereo vision system (SVS) using random pattern projection. A triangular mesh is considered as the resulting geometric model. In order to obtain reasonable results with the SVS-based geometric model generation, we deal with many steps including camera calibration, stereo matching, scanning from multiple views, noise handling, registration, and triangular mesh generation. To acquire reliable stere matching, we project random patterns onto the object. With experiments using various random patterns, we propose several tips helpful for the quality of the results. Some examples are given to show their usefulness.

• 한국컴퓨터그래픽스학회논문지
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• 제2권2호
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• pp.69-74
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• 1996

최근 점점 통합되는 세계시장과 증가하는 경쟁에서 살아남기 위해 시간과 공간의 제약을 받지 않고 제품정보를 공유할 수 있는 기술의 확보가 요구되고 있다. 제품정보의 공유를 위한 방안으로 제품정보를 중립형태의 표준으로 표현해 네트워크를 통해 전송하는 방법이 있다. 본 논문에서는 인터넷상에서 STEP 물리적 파일의 3차원 형상정보를 가시화하는 방법을 소개한다. 제품정보의 국제표준으로 새롭게 제시되는 STEP에서 형상정보가 어떻게 표현되는지 알아보고, 인터넷 환경에서의 프로그래밍 언어인 자바와 3차원 데이터 포맷인 VRML을 이용하여 형상정보를 가시화한 후 각각의 장단점을 파악하여, STEP 모델 가시화 기술을 자동차 PDM에 적용해 본다.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2007년도 학술대회
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• pp.251-255
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• 2007

In this paper, propagation analysis method in using 3D Ray Tracing propagation model in wireless cell planning is proposed. Through 3D Ray Tracing model, we can predict the distribution of propagation loss of the received signal. For correct and a low complex analysis, Quad Tree and Pre-Ordering and Hash Function algorithms are included in 3D Ray Tracing algorithm. And 3D Ray Tracing model is embodied in CellTREK that is developed by KT and used to plan Wibro system analysis. In CellTREK, propagation analysis is performed and that result is represented in 3D viewer. In numerical results, it is showed that the proposed scheme outperforms Modified HATA model when comparing with measurement data.

• 한국의류산업학회지
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• 제12권5호
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• pp.642-649
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• 2010

This study was designed to generate briefs pattern for women in their twenties using 3D parametric body model. 151 women in their 20's were random sampled and measured using Martine's anthropometry. And one subject was chosen as the representative subject for 3D scanning. Parametric model was generated of using CATIA P3, Unigraphics NX4.0, Rapidform 2006. And the 3D surface of parametric body model was flattened onto the 2D plane. 3 downscale ratios(0%, 10%, 15%) were applied to generated pattern to figure out what downscale ratio was suitable to make briefs with stretch fabric. 4 kinds of experimental briefs were made with stretch fabrics(0%, 10%, 15% downscale) and worn on the dressform. Subjective evaluation on the appearance was done and the data was analyzed by ANOVA with post-hoc test. Briefs pattern was generated through the process of flattening the parametric surface and arranging the patches to make briefs pattern by dart manipulation. The different ration of outline and area between 3D surface and 2D pattern were 0.22% and 0.09% respectively. It showed that a parametric model could provide a desirable pattern with minute size error. The results of subjective evaluation on the appearance of 4 experimental briefs showed that stretch briefs with 15% downscale ratio was evaluated most highly in most items. Findings imply that it is feasible to apply 3D parametric model to generate patterns for various items considering various fabric properties.

• 한국CDE학회논문집
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• 제20권4호
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• pp.385-400
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• 2015

ISO 15926 is an international standard for the integration and sharing of plant lifecycle data. Plant 3D design data typically consist of logical configuration, equipment specifications and ports, and 3D shape data. This paper presents the method for the ISO 15926-based integration of plant 3D design data. For this, reference data (class, attribute, and template) of ISO 15926 were extended to describe plant 3D design data. In addition to the data model extension, a plant design information integration platform which reads plant 3D design data in ISO 15926 and displays 3D design information was developed. Finally, the prototype platform is verified through the experiment of loading and retrieving plant 3D design data in ISO 15926 with the platform.

• 한국산학기술학회논문지
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• 제18권3호
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• pp.56-62
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• 2017

최근 3차원 공간정보에 대한 수요가 증가하면서 국토교통부, 서울시, 다음 카카오 등 여러 지자체 및 관련 업계에서 서비스를 구축하여 제공하고 있다. 이러한 지도 기반의 3차원 공간정보서비스에서 위치정확도는 특정 업무의 활용 가능성을 결정짓는 중요한 요소이다. 기존의 BIM 데이터는 상대좌표값으로 작성되어 절대좌표값을 갖는 GIS 데이터와 연계하는데 어려움이 있었다. 따라서 본 연구는 BIM/GIS 플랫폼 기반 모델링 데이터 구축을 통해 실내외 3차원 공간정보 간의 위치보정 방안을 제시하였다. 이를 위하여 플랫폼 테스트베드 대상을 선정한 후 데이터 구축 프로세스를 총 3단계로 진행하고, 실내공간정보를 다루는 BIM 모델과 실감형 가시화를 위한 정사영상 기반 3차원 텍스처링 모델 간 위치 불일치의 문제점을 파악하여 위치보정 알고리즘을 설계하였다. 단일 건물을 대상으로 상대좌표 기반의 BIM 모델 데이터를 절대좌표 기반의 텍스처링 데이터와 연계하기 위해 절대좌표 변환 알고리즘을 구현하여 건물의 절대위치를 1차 계산하고 BIM/GIS 플랫폼 지도상에서 텍스처링 데이터와 2차 매핑하여 3차원 모델 데이터의 최종 위치를 보정하였다.

• International journal of advanced smart convergence
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• 제6권4호
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• pp.88-95
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• 2017

The conventional scan methods are based on a laser scanner and a depth camera, which requires high cost and complicated post-processing. Whereas in photometric scanning method, the 3D modeling data is acquired through multi-view images. This is advantageous compared to the other methods. The quality of a photometric 3D model depends on the environmental conditions or the object characteristics, but the quality is lower as compared to other methods. Therefore, various methods for improving the quality of photometric scanning are being studied. In this paper, we aim to investigate the effect of illumination conditions on the quality of photometric scanning data. To do this, 'Moai' statue is 3D printed with a size of $600(H){\times}1,000(V){\times}600(D)$. The printed object is photographed under the hard light and soft light environments. We obtained the modeling data by photometric scanning method and compared it with the ground truth of 'Moai'. The 'Point-to-Point' method used to analyseanalyze the modeling data using open source tool 'CloudCompare'. As a result of comparison, it is confirmed that the standard deviation value of the 3D model generated under the soft light is 0.090686 and the standard deviation value of the 3D model generated under the hard light is 0.039954. This proves that the higher quality 3D modeling data can be obtained in a hard light environment. The results of this paper are expected to be applied for the acquisition of high-quality data.

• 스마트미디어저널
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• 제9권2호
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• pp.22-32
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• 2020

The hippocampal volume atrophy is known to be linked with neuro-degenerative disorders and it is also one of the most important early biomarkers for Alzheimer's disease detection. The measurements of hippocampal pure volumes from Magnetic Resonance Imaging (MRI) is a crucial task and state-of-the-art methods require a large amount of time. In addition, the structural brain development is investigated using MRI data, where brain morphometry (e.g. cortical thickness, volume, surface area etc.) study is one of the significant parts of the analysis. In this study, we have proposed a patch-based ensemble model of 3-D convolutional neural network (CNN) to measure the hippocampal pure volume from MRI data. The 3-D patches were extracted from the volumetric MRI scans to train the proposed 3-D CNN models. The trained models are used to construct the ensemble 3-D CNN model and the aggregated model predicts the pure volume in one-step in the test phase. Our approach takes only 5 seconds to estimate the volumes from an MRI scan. The average errors for the proposed ensemble 3-D CNN model are 11.7±8.8 (error%±STD) and 12.5±12.8 (error%±STD) for the left and right hippocampi of 65 test MRI scans, respectively. The quantitative study on the predicted volumes over the ground truth volumes shows that the proposed approach can be used as a proxy.

• 디지털콘텐츠학회 논문지
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• 제18권2호
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• pp.383-392
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• 2017

본 논문은 다시점 영상 획득에서 영상 기반 3D 모델 생성까지 실시간으로 처리가 가능한 실시간 3D 모델 생성 시스템을 소개한다. 이 시스템은 18대의 카메라에서 입력되는 HD급 영상을 수집, 전송, 관리하는 방법을 소개하며, 전경과 배경의 분리와 부드러운 3D 볼륨 모델 생성 과정을 설명한다. 이 논문은 18대의 카메라에서 입력되는 HD급 영상을 실시간으로 처리하기 위한 새로운 분산 데이터 송수신 및 관리 방법을 제안한다. 또한, 다시점 영상으로부터 부드러운 3D 모델을 생성하기 위한 시각 차이를 이용한 코드북 기반 전경과 배경 분리 알고리즘, 원근 보정 보간법을 이용한 수정된 마칭 큐브 알고리즘을 기술한다. 이 시스템은 현재 초당 30프레임 처리 속도로 구축되어 있다.