• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1999년도 KOBA 방송기술 워크샵 KOBA Broadcasting Technology Workshop
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• pp.133-140
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• 1999

In this paper, we propose a method of image-based three-dimensional modeling for realistic facial expression. In the proposed method, real human facial images are used to deform a generic three-dimensional mesh model and the deformed model is animated to generate facial expression animation. First, we take several pictures of the same person from several view angles. Then we project a three-dimensional face model onto the plane of each facial image and match the projected model with each image. The results are combined to generate a deformed three-dimensional model. We use the feature-based image metamorphosis to match the projected models with images. We then create a synthetic image from the two-dimensional images of a specific person's face. This synthetic image is texture-mapped to the cylindrical projection of the three-dimensional model. We also propose a muscle-based animation technique to generate realistic facial expression animations. This method facilitates the control of the animation. lastly, we show the animation results of the six represenative facial expressions.

• 한국가시화정보학회지
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• 제19권3호
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• pp.92-98
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• 2021

Large Eddy Simulation (LES) has been popularly applied and used in the last several decades to simulate turbulent boundary layer in the numerical domain. A fully developed turbulent boundary layer has also been applied to predict the complicated wake flow behind bluff bodies. In this study we aimed to generate an artificial turbulent boundary layer, which is based on an exponential correlation function, and generates a series of realistic three-dimensional velocity data in two-dimensional inlet section which are correlated both in space and in time. The results suggest its excellent capability for high Reynolds number flows. To make an effective generation, a hexahedral mesh has been used and Cholesky decomposition was applied to possess suitable turbulent statistics such as the randomness and correlation of turbulent flow. As a result, the flow characteristics in the domain and fluctuating pressure near the wall are very close to those of fully developed turbulent boundary layers.

• 한국물환경학회지
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• 제21권5호
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• pp.458-463
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• 2005

Considering the characteristics of a filtration bio-reactor equipped with a mesh filter module which can effectively maintain high concentration of biomass and enhanced solid-liquid separation performance, the hybrid process of filtration bio-reactor combined with coagulation was investigated to get improved filtration characteristics as well as water quality in this work. Two bio-reactors (Run-1 & Run-2) were operated under the following conditions: working volume of 25 L, continuous loading of a synthetic wastewater (BOD: 200 mg/L, T-N: 50 mg/L, T-P: 5 mg/L), where an appropriate amount of alum ($Al_2(SO_4)_3{\cdot}18H_2O$) was added once a day into the reactor (Run-2). In the system without using a alum (Run-1), the clogging of mesh filter module was observed two times through 85 days of whole operation. Meanwhile, the filter module did not clog even at higher MLSS concentration (6,000~12,000 mg/L) and the stable filtration (0.7 mid) was continued in the case of using a alum. Due to the stable formation of cake layers, BOD and SS were shown below 6 and 3 mg/L, respectively. T-P and pH of the effluent were changed because of the intermittent addition of the alum. In the case of Al/P=2.5, the average T-P removal efficiency per day was 85.2% and the average T-P concentration of the effluent was 0.3 mg/L. However, the removal efficiency of phosphate was influenced by pH in the reactor.

• Archives of Plastic Surgery
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• 제38권2호
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• pp.135-142
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• 2011

Purpose: Deficiencies of the abdominal wall can be the a result of infection, surgery, trauma, or primary herniation. For abdominal wall reconstruction, synthetic materials have been shown to provide a better long-term success rate than primary fascial repair. But, synthetic materials cannot elicit angiogenesis or produce growth factor and are therefore plagued by an inability to clear infection. As a result of the inherent drawbacks of synthetic, significant effort has been spent on the identification of new bioprosthetic materials. The aim of our study is to evaluate the effectiveness of a synthetic material (PROCEED$^{(R)}$) and an ADM ($SureDerm^{TM}$) to repair abdominal wall defects in a rabbit models. Methods: We measured the tensile strength of the $SureDerm^{TM}$ and PROCEED$^{(R)}$ by a Tension meter (Instron 4482). 16 Rabbit models were assigned to this study for abdominal wall reconstruction. Abdominal defect of 8 rabbits were reconstructed by PROCEED$^{(R)}$ and the rest were reconstructed by $SureDerm^{TM}$. We assessed gross and histologic examinations for the reconstructed abdominal wall. Results: The tensile strength of $SureDerm^{TM}$ and Gore Tex$^{(R)}$ is $14.64{\pm}0.51Mpa$, $8.54{\pm}0.45Mpa$. PROCEED$^{(R)}$ was estimated above the limits of measurement. Inflammatory reaction of PROCEED$^{(R)}$ persisted for 32weeks, but $SureDerm^{TM}$ decreased after 16weeks. Vascular ingrowth into the $SureDerm^{TM}$ was seen after 32 weeks. The basement membrane of $SureDerm^{TM}$ changed into a form of pseudoperitoneum. In PROCEED$^{(R)}$, it seemed like pseudoepithelial lining was made from the fibrosis around the mesh. Conclusion: In our study, the $SureDerm^{TM}$ not only have less inflammatory reaction and presented more angiogenesis than the PROCEED$^{(R)}$, but also have pseudoperitoneum formation. It is expected that $SureDerm^{TM}$ is useful for abdominal wall reconstruction. However, a long-term study of its usage consequences are thought to be needed.

• 방송과미디어
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• 제3권2호
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• pp.44-58
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• 1998

최근의 멀티미디어 기술은 정보의 디지털화와 온라인화에 따라 가전, 컴퓨터, 통신 및 방송 기술이 융화되어 가는 추세에 있으며, 대화형의 하이브리드 멀티미디어 기술을 그 특징으로 하고있다. 하이브리드 멀티미디어는 컴퓨터 그래픽 및 미디(MIDI) 기술로 인위적으로 생성한 2D/3D그래픽 및 음향을 실제의 자연적인 영상과 소리에 추가하여 합성하므로 생성된다. MPEG-4는 이렇게 인위적으로 합성되거나 자연적인 영상 혹은 음향 정보의 디지털 하이브리드 멀티미디어 부호화를 목적으로 하며, 활성화된 혼합 미디어의 내용기반 처리, 상호, 동작 및 사용자의 쉬운 접근 등을 가능하게 한다. SNHC(Synthetic-Natural Hybrid Coding)는 기존의 수동적인 미디어의 전달뿐 아니라 실시간 처리가 가능한 인터랙티브 응용 분야까지 다루고 있으며, 통합된 시공간 부호화 기법을 사용하여 시각, 청각, 2차원, 3차원 컴퓨터 그래픽스 등 다양한 형태의 표준 AV(Aural/Visual) 객체를 처리한다. 표준화는 주로mesh-segmented 비디오 부호화, 구조물 부호화, 객체간의 동기화, AV 객체 스트림의 멀티플렉싱, 혼합 미디어 형태의 시-공간 통합화 등에서 이루어지게 되는데, 이는 궁극적으로 네트워크로 연결되는 가상 환경(Virtual Environment)에서 다수의 사용자가 서로 상호작용 할 수 있는 틀을 제공하는데 있다. 이러한 틀이 제공되면, 대화형 하이브리드 멀티미디어라는 새로운 형태의 정보를 사용함으로써 기존의 미디어로는 경험하지 못하는 다양한 응용과 서비스를 경험할 수 있을 것이다.

• 한국농공학회논문집
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• 제50권4호
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• pp.89-97
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• 2008

A downdraft gasifier was manufactured for biomass gasification. The gasifier was designed based on the principles of gasification presented in previous studies. The pipes of 25mm diameter were used for both supplying air and discharging producer gas. Wood charcoals were mostly used for fuels. The concentration of CO ranged from 25 to 35%, comparable to the values presented in other studies. The temperature outside wall of the gasifier was measured up to $400^{\circ}C$, indicating a great heat loss. When glass wool was cover over the wall, some parts of wire mesh located in the bottom of the reactor were molten down. There were several modifications that should be made in order to improve its efficiency and obtain more stable continuous gasification, including insulation, reduction in pressure loss, durable bottom meshes, the optimum length of reaction part, and safety.

• 한국분말재료학회지
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• 제11권3호
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• pp.224-232
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• 2004

Ni-diamond composite powders with nickel layer of round-top type on the surface of synthetic diamond (140/170 mesh) were prepared by the electroless plating method (EN) with semi-batch reactor. The effects of nickel concentration, feeding rates of reductant, temperature, reaction time and stirring speeds on the weight percentage and morphology of deposited Ni, mean particle size and specific surface area of the composite powders were investigated by Atomic Adsortion Spectrometer, SEM-EDX, PSA and BET. It was found that nucleated Ni-P islands, acted as catalytic sites for further deposition and grown into these relatively thick layers with nodule-type on the surface of diamond by a lateral growth mechanism. The weight percentage of Ni in the composite powder increased with reaction time, feeding rate of reductant and temperature, but decreased with stirring speed. The weight percentage of Ni in Ni-diamond composite powder was 55% at 150 min., 200 rpm and 7$0^{\circ}C$ .

• 한국수산과학회지
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• 제33권5호
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• pp.423-430
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• 2000

건조미역 또는 염장미역의 제조부산물로 얻어지는 미역 줄기를 이용하여 기호성이 뛰어난 미역줄기잼의 제조를 시도하였다. 잼의 주원료인 미역줄기 페이스트는 자숙, 염장한 미역줄기를 물에 침지하여 탈염하고 물기를 뺀 후, 2.5배의 물을 가하여 초퍼와 homogenizer를 차례로 써서 균질화한 다음, $30{\~}50\;mesh$ 체로 여과하여 제조하였다. 미역줄기잼은 미역줄기 페이스트에 sucrose, HM pectin (또는 LM pectin) 및 유기산 (또는 유기염)을 순차적으로 첨가하면서 일정 농도까지 가열, 농축한 다음 미역취를 차폐할 목적으로 인공 딸기향을 일정량 가하여 제조하였다. 잼 제조시 sucrose, pectin, 유기산 및 유기염이 제품의 물성에 미치는 영향을 기계적 및 관능적으로 살펴본 결과, 미역줄기 페이스트에 sucrose $65{\%}$ (w/w), HM pectin $1.0{\%}$ (w/w) 및 citric acid $0.3{\%}$ (w/w) 또는 sucrose $65{\%}$ (w/w), LM pectin $1.0{\%}$ (w/w) 및 calcium lactate $0.08{\%}$ (w/w)를 첨가하여 $62 {\cdot}Brix$로 한 제품이 물성면에서 시판 과일잼 (딸기 및 사과잼)과 유사하였고, 미역 특유의 바람직하지 못한 해조취를 차폐하기 위해 인공 딸기향을 사용한 결과 $0.06{\%}$ (v/w) 이상 첨가하여 만든 제품이 시판 과일잼과 비교하여 관능적으로 손색이 없는 제품이었다.

• Journal of Korean Neurosurgical Society
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• 제61권6호
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• pp.737-746
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• 2018

Objective : The purpose of this study was to compare the cosmetic outcome and complications after cranioplasty (CP) due to three different implant materials, and analyze the mean implant survival and cumulative survival rate based on these results. Methods : We reviewed 108 patients retrospectively who underwent CP between January 2014 and November 2016. Autologous bone (AB; 45 patients) and synthetic materials with porous polyethylene (PP; 32 patients) and custom-made 3-dimensional printed titanium mesh (CT; 31 patients) were used as implants. Results : Regardless of implanted materials, more than 89.8% of the CP patients were satisfied with the cosmetic outcome. No statistically significant difference was observed among the three groups. The overall postoperative complication rates of each group were 31.1% in the AB group, 15.6% in the PP group and 3.2% in the CT group. The CT group showed lower complication rates compared with AB and PP groups (${\chi}^2$-test : AB vs. PP, p=0.34; AB vs. CT, p=0.00; PP vs. CT, p=0.03). The AB and PP groups demonstrated a higher post-CP infection rate (11.1% and 6.3%) than the CT group (3.2%). However, no significant difference in the incidence of post-CP infection was observed among the three groups. The PP and CT groups demonstrated a higher mean implant survival time and cumulative survival rate than the AB group at the last follow-up (p<0.05). Conclusion : In comparison with AB and PP, cranioplasty with CT shows benefits in terms of lower post-CP complication, less intraoperative bleeding loss, shorter operation time and in-hospital stay. The PP and CT groups showed higher implant survival time and cumulative survival rate compared with the AB group.

• 지구물리와물리탐사
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• 제4권2호
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• pp.34-44
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• 2001

종래의 탄성파 모델링은 지표를 수평면으로 가정하고 그 아래쪽에 여러 개의 반사면에 대한 모델링이 대부분 이었다. 그러나, 실제 탐사에서는 복잡한 지형을 가진 지표에서 탐사가 수행되기 때문에 탄성 매질에서의 반응을 명확하게 구분해 내는 것이 힘들다. 지표에 탄성파 전파특성을 규명하기 위하여 모델에 지형을 고려할 수 있도록 하여 시간영역 유한요소법을 이용하여 매질의 반응을 구하였다. 이러한 이러한 알고리즘을 이용하여 지표에서 진원을 가했을 때 수평 및 제방(mound), 채널(channel)등의 구조로부터 지표의 수신기에서 합성 탄성파 기록을 관찰하고, 스냅사진(snapshot)을 얻어냄으로써 해석해와 잘 일치함을 확인하였고, 지표 및 지하 반사면에 의한 복잡한 탄성파의 전파 양상을 파악할 수 있었다. 불규칙 지표면을 따라 전파하는 표면파가 모서리에서 새로운 진원으로 작용하여 큰 잡음이 생성됨을 관찰하였고, 지표를 따라 전파하는 높은 에너지의 레일리파, 상대적으로 낮은 압축파, 전단파 등의 전파 양상으로부터 파의 천이 상태를 관찰할 수 있었다.