• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.361-364
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• 2004

This paper describes an automatic 3D models generation algorithm based on 2D silhouette images, using X-ray camera without camera parameters. The algorithm takes a multi steps process approach. First, a series of 2D silhouette images is captured from different directions of object and then converted to binary images. An octree data structure is constructed for voxel-based representation of object. An estimate 3D volume of object can be reconstructed by intersecting voxels and the 2D silhouettes. The marching cube algorithm is applied to get triangle mesh representing of the obtained 3D model for rendering.

• 대한전기학회논문지:시스템및제어부문D
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• 제54권11호
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• pp.673-679
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• 2005

This Paper presents the 3D wavelet transformation based video compression system, which possesses the capability of progressive transmission by increasing resolution and increasing rate for multimedia applications. The 3D wavelet packet based video compression system removes the temporal correlation of the input sequences using the motion compensation filter and decomposes the spatio-temporal subband using the spatial wavelet packet transformation. The proposed system allocates the higher bit rate to the low frequency image of the 3D wavelet sequences and improves the 0.49dB PSNR performance of the reconstructed image in comparison with that of H.263. In addition to the limitation on the propagation of the motion compensation error by the 3D wavelet transformation, the proposed system progressively transmits the input sequence according to the resolution and rate scalability.

• 한국의학물리학회지:의학물리
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• 제30권4호
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• pp.120-127
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• 2019

Purpose: This study was designed to evaluate the dosimetric performance of Mobius3D by comparison with an aSi-based electronic portal imaging device (EPID) and Octavius 4D, which are conventionally used for patient-specific prescription dose verification. Methods: The study was conducted using nine patients who were treated by volumetric modulated arc therapy. To evaluate the feasibility of Mobius3D for prescription dose verification, we compared the QA results of Mobius3D to an aSi-based EPID and the Octavius 4D dose verification methods. The first was the comparison of the Mobius3D verification phantom dose, and the second was to gamma index analysis. Results: The percentage differences between the calculated point dose and measurements from a PTW31010 ion chamber were 1.6%±1.3%, 2.0%±0.8%, and 1.2%±1.2%, using collapsed cone convolution, an analytical anisotropic algorithm, and the AcurosXB algorithm respectively. The average difference was found to be 1.6%±0.3%. Additionally, in the case of using the PTW31014 ion chamber, the corresponding results were 2.0%±1.4%, 2.4%±2.1%, and 1.6%±2.5%, showing an average agreement within 2.0%±0.3%. Considering all the criteria, the Mobius3D result showed that the percentage dose difference from the EPID was within 0.46%±0.34% on average, and the percentage dose difference from Octavius 4D was within 3.14%±2.85% on average. Conclusions: We conclude that Mobius3D can be used interchangeably with phantom-based dosimetry systems, which are commonly used as patient-specific prescription dose verification tools, especially under the conditions of 3%/3 mm and 95% pass rate.

• 한국의류산업학회지
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• 제21권3호
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• pp.267-276
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• 2019

This study develops 3D-printed-garment collections for a fashion show presentation. A design concept using traditional patterns that consisted of garments regarding the limitation of the printing technology was investigated in order to develop the collection. The structures of the connecting joints of the textile parts which could be easily and sturdily interconnected were invented. Wearability as garments that could be naturally worn on the human body were sought. As a result, four 3D-printed-garments were developed. The 1st garment composed of objects based on a 'Yeon-Dang-Cho'-pattern was constructed as a geometric robe style using a FDM 3D printer and transparent TPU filaments. The 2nd and 3rd 3D-printed-garments composed of an object based on a 'Boe-Sang-Hwa'-pattern was constructed as a distorted one-piece exaggerating the silhouettes of shoulders and waist parts as well as a straight asymmetric tunic style that used the same printer and material as the 1st garment. The last garment composed of an object based on a 'Boe-Sang-Hwa'-pattern printed using a SLA 3D printer and flexible-liquid-resin was constructed attaching the objects on the fabric material by the hot-press machine. The four developed garments were presented in the opening fashion show of 'the 6th International 3D-printing Korea Expo'. This study provides a basic case for related studies to adapt 3D-printing technology in textile pattern development of garment construction.

• 한국산학기술학회논문지
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• 제7권1호
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• pp.33-38
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• 2006

본 논문은 웹 기반 3D 패션몰 구축 시 필요한 3D 모델의 패션쇼 애니메이션 설계 기법 및 구현방법에 대해 제안한다. 3D MAX를 이용하여 제작된 3D 모델을 XML(Extensible Markup Language) 형식으로 출력시킨 후, D3D(Direct 3D)를 사용하여 제작된 ActiveX 컨트롤을 이용하여 웹상에 구현하였다. 소비자가 웹기반 패션몰에서 선택한 다양한 의상을 입은 3D 모델의 패션쇼 애니메이션을 구현하기 위해, 기본형태의 3D 모델에 계층적 구조를 가진 근사 의상을 이용하여 표현하였다. 근사의상은 표준 의상 조각들을 설계하고 제작한 후, 이를 조합하는 방식으로 구현하였으며, 여기에 텍스처를 맵핑하여 소비자가 선택한 의상의 근사 모델이 표현 될 수 있도록 구현 하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권1호
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• pp.206-221
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• 2019

Source localization in three-dimensional (3-D) wireless sensor networks (WSNs) is becoming a major research focus. Due to the complicated air-ground environments in 3-D positioning, many of the traditional localization methods, such as received signal strength (RSS) may have relatively poor accuracy performance. Benefit from prior learning mechanisms, fingerprinting-based localization methods are less sensitive to complex conditions and can provide relatively accurate localization performance. However, fingerprinting-based methods require training data at each grid point for constructing the fingerprint database, the overhead of which is very high, particularly for 3-D localization. Also, some of measured data may be unavailable due to the interference of a complicated environment. In this paper, we propose an efficient kernel based 3-D localization algorithm via tensor completion. We first exploit the spatial correlation of the RSS data and demonstrate the low rank property of the RSS data matrix. Based on this, a new training scheme is proposed that uses tensor completion to recover the missing data of the fingerprint database. Finally, we propose a kernel based learning technique in the matching phase to improve the sensitivity and accuracy in the final source position estimation. Simulation results show that our new method can effectively eliminate the impairment caused by incomplete sensing data to improve the localization performance.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2002년도 학술대회지
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• pp.188-191
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• 2002

This paper concerns 3-D graphical modeling and simulation techniques for design and control of automated equipment for construction and facility maintenance. A case study on the use of 3-D graphics techniques for developing a power plant maintenance robot is presented. By simulating equipment operation within the 3-D geometry models of the work environment the environment design was improved. The 3-D graphical models of the equipment and the work environment were further utilized for the control of the robot from a remote distance. By presenting the real-time updated equipment configuration and the work environment to the operator, the graphical model-based equipment control system helped the operator overcome the problems associated with spatial perception. The collision between the robot and the plant structures was also avoided based the real-time analysis of the dynamically updated graphical models.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2002년도 추계학술대회 논문집
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• pp.15-18
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• 2002

We propose an image based three-dimensional shape determination system. The shape, and thus the three-dimensional coordinate information of the 3-D object, is determined solely from captured images of the 3-D object from a prescribed set of viewpoints. The approach is based on the shape from silhouette (SFS) technique and the efficacy of the SFS method is tested using a sample data set. This system may be used to visualize the 3-D object efficiently, or to quickly generate initial CAD data for reverse engineering purposes. The proposed system potentially may be used in three dimensional design applications such as 3-D animation and 3-D games.

• 인터넷정보학회논문지
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• 제17권6호
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• pp.41-51
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• 2016

3D-Touch 인터페이스의 등장은 사용자로 하여금 새로운 인터랙션을 제공할 수 있는 기반을 마련해 주었다. 하지만 일부 스마트폰에서만 3D-Touch가 제공되고 있고, 대부분 2D-Touch 스마트폰에서 사용되는 인터랙션 방법은 새로운 방식의 3D-Touch의 인터랙션을 제대로 적용할 수 있는 방안은 마련되지 않고 있다. 이는 3D-Touch와 2D-Touch 인터랙션에서의 차이가 발생하는 주요 원인이다. 이에 따라 본 연구에서는, 2D-Touch 기반 디바이스에서도 3D-Touch의 소프트웨어적 기능과 인터페이스를 활용할 수 있게 해주는 가상 포스 터치 (Virtual Force Touch) 방식을 이용해서 3D-Touch 인터페이스를 활용할 수 있는 방안에 대하여 제안한다. 제안한 방안은 2D-Touch를 제공하는 스마트폰에서 사용자가 포스터치 입력을 발생하였을 때 스마트폰에 차지하는 손가락 면적을 분석하여 적절한 가상 포스 터치 구현하기 위한 것이다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.68-69
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• 2018

The construction drawing is a collection of knowledge that has accumulated knowledge and experience of designers and is highly valuable for recycling in the future. BIM is a process and technology that acquires and manages the information needed for the whole life cycle of a building. In order to recycle digitalized 2D drawings in BIM Tool, it is required to use 3D information based on the drawing information to save and reuse them, but there is little research on related methods or system development. In this study, 3D elements are created based on 2D drawing information, and libraries are constructed, and BIM Tool is used to improve the recyclability of drawing information.