• Annual Conference of KIPS
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• 2010.04a
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• pp.523-526
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• 2010

주어진 경계선에 대해 비누막이 생성하는 표면 모델링 및 시간에 따른 변형 시뮬레이션은 컴퓨터 그래픽스 응용 프로그램의 한 분야이다. 이 문제에 대한 이전의 연구들은 주로 기하적인 방법들을 이용하였기 때문에 물리적으로 정확한 변형을 다루지 못하였다. 본 연구에서는 정확한 기하를 바탕으로 물리기반 변형을 다루기 위해 이산미분기하학으로부터 비누막의 동적인 모델을 제안한다. 우선, 비누 성분의 물리적인 특성들을 고려한 에너지 모델을 정의하고, 이를 이산 영역에서 나타내기 위해 이산미분기하 및 이산화 기법들을 이용한다. 제안하는 모델은 평형 상태에서의 비누막 형상뿐만 아니라 외력에 대한 표면의 변형까지 정확하게 나타내며, 실시간 시뮬레이션이 가능하여 게임, 애니메이션 목적으로 활용될 수 있다.

• Membrane Journal
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• v.17 no.4
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• pp.375-380
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• 2007

To recover sericin protein from by-product in silk production process, a polyethersulfone hollow fiber ultra-filtration membrane module was used. The soap in the degummed solution was precipitated by calcium chloride. The influence of membrane module of submerged and external type on membrane fouling was investigated. The effect of soap and protein on the membrane fouling in the external type membrane module was also studied. The removal of soap resulted in decreasing the membrane fouling. It was shown that the protein and the membrane were affected by the soap.

• The Journal of the Convergence on Culture Technology
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• v.6 no.2
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• pp.455-460
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• 2020

As computer hardware and computer graphics technologies have developed in recent years, one can find research on the creation of bubbles. However, it is not easy to find soap bubbles that are modeled and rendered using actual physical parameters. The bubbles are expressed in a variety of models and colors depending on which tool is used, which strength is used, and the conditions of the surrounding environment. Therefore, in this paper, we present synthetic methods to create virtual soap bubbles based on physical parameters derived from some straws such as the bubbles' diameter over time and the number of bubbles when blowing. On the top of that, we will show a model of a soap bubble that can be usable in a virtual reality contents and optimized with rendering parameters.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.4
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• pp.121-127
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• 2008

Automatic grease lubricator is an equipment that provides adequate amount of fresh grease constantly to the shaft and bearings of machines. It minimizes the friction heat and reduces the friction loss of machines to the least. This paper is developing an automatic grease lubricator using a mode of the gas generation type from galvanic electricity. The ultimate goal of this equipment is to lubricate an adequate amount of grease with galvanic corrosion. In an electrolyte, combining anode(Mo) with cathode(Zn) is pressing out hydrogen gas of an galvanic element with galvanic reaction. The characteristics of this method is continuous flowing small hydrogen gas and controling the usage of the amount of the generation of hydrogen gas. The exterior body of grease lubricator was analyzed by Digital Mock-up of CATIA V5 and finite element analysis. The maximum stress is distributed over the outlet part where the grease lubricator suddenly narrowly contracts. The outlet part is analyzed with different constructed angle due to the different loading and setting angles. Using the analyzed design, RP trial products were producted and tested.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.2
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• pp.94-101
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• 1989

Transport properties of 2DEG at AlGaAs/GaAs interface such as average electron energy, flight distance, each valley occupancy ratio, average electron velocity for various fields are investigated by MONTE-CARLO method. As the electric field increases, more electrons transit drastically from (000) valley to (000) upper valley. This phenomenon shows the nonstationary effect such as velocity overshoot. The duration of the transient decreases from about 1.4 psec for electric field E = 7KV/cm to about 0.7 psec for 12KV/cm. The average electron velocity during transient transport in 2DEG is about 8 times the steady-state velocity for E = 12KV/cm at room temperature. In comparison with bulk GaAs the peak velocity in the 2DEG is higher than that in even pure bulk GaAs at electric field E = 7 KV/cm. On the basis of the fact that the electrons in the 2DEG have larger peak velocity and shorter transient time of velocity than those in the bulk GaAs, it is suggested that the device with 2DEG may obtain higher mobility than that with bulk GaAs.

• Childhood Kidney Diseases
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• v.1 no.2
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• pp.144-150
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• 1997

Purpose : The kidney is one of the most common sites of cyst formation. Cystic diseases of the kidney are a diverse group of clinicopathologic entities and variable prognosis. They span a wide range of both age of presentation and severity of the renal disease. And many of them are systemic disorders, sharing similar process of cyst formation in other organs. Recently, development of imaging studies has been contributing widely to the diagnosis of the diseases. Treatment, however, is not established satisfactorily. We performed this study to evaluate the occurrence and treatment of cystic diseases of the kidney. Methods : We reviewed retrospectively the medical records of 44 patients with cystic diseases of the kidney in the Department of Pediatrics, during last 11 years. Results : In the 44 patients with cystic diseases of the kidney, 31 patients(71%) had multicystic dysplastic kidney and 11(35%) of them received nephrectomy due to differentiation from neoplasms or severe abdominal distension. Seven patients(16%) had polycystic kidney disease, and all of them were infantile type. Five patients(11%) were diagnosed as having a simple renal cysts. Progression to renal failure was noted in none of the cases. In 14(32%) out of total 44 patients, the diagnosis was made in neonatal or infantile pelted. Conclusion : The incidence of cystic diseases of the kidney appeared very low, but further investigation on their pathogenesis, classification, and indication of treatment is needed.