• Journal of Korean Society on Water Environment
• /
• v.27 no.1
• /
• pp.30-35
• /
• 2011

2D pollutant transport model was applied to the simulation of contaminant transport in the channel. At first, two kinds of virtual channels having different slopes were designed. The distribution of contaminant, which flows from one of the three drainages to the main channel, was simulated by each 2D model. Concentrations of 745 nodes were converted to input data of neural network model (Multi-perceptron) for training and verification using matrix. The first three cases (Case A-1, A-2, A-3) were used for training Multi-perceptron, the other three cases (Case B-1, B-2, B-3) were used for verification. As a result, Multi-perceptron reasonably divided the cases into the three characteristics which have different contaminant distributions due to the different input point of water pollution source. It can be a useful methodology for the water quality monitoring and backtracking.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.3 no.1
• /
• pp.1-14
• /
• 1997

This paper describes a series of numerical simulations of colision between a 310, 000 DWT double hull VLCC (struck ship) and three 35, 000, 70, 000 and 105, 000 DWT tankers (striking ships) using LS/DYNA3D. Collisions are assumed to occur at the middle of the VLCC with the striking ships moving at right angle to the VLCC centerline. Striking ship speeds are varied to find a critical speed without failure of inner side shell, and the informations of collision force and absorption energy of each case are also reported. The validation of LS/DYNA3D in this study was made by comparing the result of numerical simulation of LS/DYNA3D with that of double hull tanker grounding experiment by the Carderock Division of Navla Surface Warfare Center (CDNSWC).

• The Journal of the Korea institute of electronic communication sciences
• /
• v.7 no.5
• /
• pp.1005-1010
• /
• 2012

The Augmented Reality, as a technology caught the spotlight as a next generation's technology of inserting 3D virtual objects in the space of reality seen through the camera, can maximize the learning effects by inducing user's absorption and interest using interaction between user and objects. Recently, as the movile devices having excellent mobility and portability are generalized, the diversified augmented reality are introduced using mobile devices. In this article, a 3D fish encyclopedia system augmented from the mobile environment was designed to provide the user with learning contents focusing on the sense of absorption and an interest. This system is intened to provide helps to learn about the fishes by recognizing the pictures of fishes in the encyclopedia as marker, bringing out the 3D model stored in server and displaying in the mobile environment.

• Journal of the Korean GEO-environmental Society
• /
• v.20 no.10
• /
• pp.5-14
• /
• 2019

Recently, earthquakes have occurred in our country and seismic stability of high-rise buildings in large cities is being a growing interest and thus the related studies have been increased. Also the grounds are considered indirectly in most of seismic designs and analyses and seismic researches based on 3D dynamic analysis are insufficient. In this study, therefore, 2D and 3D dynamic analyses were performed based on the SSI complete model including grounds and the behavior was compared and analyzed. For dynamic modeling, linear time history analyses were performed by using MIDAS GTS NX. For this purpose, a high-rise building was assumed to be constructed on top of the bedrock and surrounded by a surface layer. A sensitivity analysis was performed with the selected parameters. The dynamic behavior was compared and analyzed in terms of horizontal displacements, drift ratios, bending stresses, and weak parts. In most cases, 2D dynamic behavior was calculated to be larger than 3D's and thus it shows more conservative results with increasing number and size of weak parts.

• Archives of design research
• /
• v.19 no.4 s.66
• /
• pp.71-80
• /
• 2006

Collaboration has become essential in the product design process due to internationalized and specialized business environments. This study presents a real-time collaborative 3D design workspace for distributed designers, focusing on the development and the evaluation of new interaction techniques supporting nonverbal communication such as awareness of participants, shared manipulation and tele-presence. Requirements were identified in terms of shared objects, shared workspaces and awareness through literature reviews and an observational study. An Augmented Reality based collaborative design workspace was developed, in which two main interaction techniques, Turn-table and Virtual Shadow, were incorporated to support shared manipulation and tele-presence. Turn-table provides intuitive shared manipulation of 3D models and physical cues for awareness of remote participants. Virtual shadow supports natural and continuous awareness of location, gestures and pointing of partners. A lab-based evaluation was conducted and the results showed that interaction techniques effectively supported awareness of general pointing and facilitated discussion in 3D model reviews. The workspace and the interaction techniques can facilitate more natural communication and increase the efficiency of collaboration on virtual 3D models between distributed participants (designer-designer, engineer, or modeler) in collaborative design environments.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2014.06a
• /
• pp.146-149
• /
• 2014

최근 ATSC는 방송망 기반의 서비스호환 3DTV 방송서비스 표준완료 이후 이종망 환경에서 하이브리드 3DTV 방송서비스에 대한 표준화를 진행 중에 있다. 본 논문에서는 기존의 디지털방송 화질열화 없이 Full HD 3D 화질을 보장하기 위한 방송망 및 IP 망 연동형 3D 비디오 방송시스템을 제안한다. 특히, ISO/IEC 23009-1 DASH를 활용한 3D 부가 영상 전송, 이종망 환경하에서 안정적인 3D 비디오 동기화 및 하이브리드 3DTV 수신기 개발을 위한 시스템 타켓 디코더 모델을 기술한다. 실험결과, 제안된 기술은 하이브리드 3DTV 방송 표준화에 직접적으로 적용될 수 있으며, 하이브리드 3DTV 인코더 및 수신기 개발에 있어서 참조 모델로 활용될 수 있음을 확인하였다.

• Proceedings of the Korea Contents Association Conference
• /
• 2006.11a
• /
• pp.682-686
• /
• 2006

There have been increasing interests in 3D mobile content service with emergence of a terminal equipping with a mobile 3D engine and growth of mobile content market. Mobile 3D Avatar is the most effective product displaying the character of a personalized mobile device user. However, previous studies on the method of expressing 3D Avatar have been mainly focused on natural and realistic expressions according to the change in facial expressions and lip shape of a character in PC based virtual environments. In this paper, we propose a method of synchronizing the lip shape with voice by applying a SMS message received in mobile environments to 3D mobile Avatar. The proposed method enables to realize a natural and effective SMS message reading service of mobile Avatar by disassembling a received message sentence into units of a syllable and then synchronizing the lip shape of 3D Avatar with the corresponding voice.

• Journal of Broadcast Engineering
• /
• v.11 no.4 s.33
• /
• pp.431-440
• /
• 2006

There are several researches on 2D gaze tracking techniques for the 2D screen for the Human-Computer Interaction. However, the researches for the gaze-based interaction to the stereo images or contents are not reported. The 3D display techniques are emerging now for the reality service. Moreover, the 3D interaction techniques are much more needed in the 3D contents service environments. This paper addresses gaze-based 3D interaction techniques on stereo display, such as parallax barrier or lenticular stereo display. This paper presents our researches on 3D gaze estimation and gaze-based interaction to stereo display.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.24 no.7
• /
• pp.873-878
• /
• 2020

Due to the recent development of 3D printers, interest in 3D printing is growing. 3D printing should reflect individual needs and various requirements by designing products to suit the user's requirements. Research on how to use 3D printed products for the purpose of purchasing products according to user's demand characteristics is insufficient. Therefore, this study conducted a survey and statistical analysis to find out the factors influencing the intention of purchasing custom controller products in 3D printing environments. Research has confirmed that user innovation and convenience safety are important factors for the satisfaction and purchase intent of personal-tailored controller products. Considering user innovation, convenience, and safety when producing controller products using 3D printing, it is expected that value of custom controller manufacturing can be increased. Research is needed on the personalized product development framework that successfully introduces and systematically supports the production methods of personalized products in the early stages.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.32 no.2
• /
• pp.153-162
• /
• 2022

Objectives: Fused deposition modeling (FDM) 3D printer which is one of the material extrusion (MEX) technologies is an additive manufacturing (AM) process. 3D printers have been distributed widely in Korea, particularly in school and office, even at home. Several studies have shown that nanoparticles and volatile organic compounds (VOCs) were emitted from an FDM 3D printing process. The objective of this study was to identify types of chemicals possibly emitted from FDM 3D printing materials such as PLA (polylactic acid), ABS (acrylonitrile butadiene styrene), nylon, PETG (polyethylene terephthalate glycol), PVA (polyvinyl alcohol), PC (polycarbonate) filaments. Methods: 19 FDM 3D printing filaments which have been distributed in Korea were selected and analyzed VOCs emitted of 3D printing materials by headspace gas chromatography mass spectrometry (headspace GC-MS). Subsamples were put into a vial and heated up to 200℃ (500 rpm) during 20 minutes before analyzing FDM 3D printing filaments. Results: In the case of PLA filament, lactide and methyl methacrylate, the monomer components of one, were detected, and the volume ratio ranged 27~93%, 0.5~37% respectively. In the case of ABS filaments, styrene (50.5~59.1%), the monomer components of one, was detected. Several VOCs among acetaldehyde, toluene, ethylbenzene, xylene, etc were detected from each FDM 3D printing filaments. Conclusions: Several VOCs, semi-VOCs were emitted from FDM 3D printing filaments in this study and previous studies. Users were possibly exposed to ones so that we strongly believe that we recommend to install the ventilation system such as a local exhaust ventilation (LEV) when they operate the FDM 3D printers in a workplace.