• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.1
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• pp.91-99
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• 2007

It was intended in this study to investigate the effects of various parameters on the chemical reaction or mass transfer yield in a tubular-type nuclear waste treatment equipment. Since such equipments, as a tubular reactor, multistage solvent extractor, and adsorption column, accompany chemical reaction or mass transfer along the fluid-flowing direction, mathematical modeling for each equipment was carried out first. Then their behaviors of the chemical reaction or mass transfer were predicted through computer simulations. The inherent major parameters for each equipment were chosen and their sensitivities. affecting the reaction or mass transfer yield were analyzed. For the tubular reactor, the effects of axial diffusion coefficient and reaction rate constant on the reaction yield were investigated. As for the multistage solvent extractor, the backmixing of continuous phase and the distribution coefficient between fluid and solvent were considered as the major parameters affecting the extraction yield as well as concentration profiles throughout the axial direction of the extractor. For the adsorption column, the equilibrium constant between fluid and adsorbent surface, and the overall mass transfer coefficient between the two phases were taken as the major factors that affect the adsorption rate.

• Nuclear Engineering and Technology
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• v.18 no.4
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• pp.261-266
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• 1986

The purpose of this research was to investigate the de-entrainment of boron for evaporators used in nuclear power plants. The forced circulation and semi-continuous type evaporator was used in the experiment. Cyclone and glass-wool packed column which is supposed to provide good decontamination factor as well as easy maintenance, were selected as de-entrainment devices to be used in the evaporation of radioactive liquid wastees. The de-entrainment device combined with cyclone and glass-wool column has shown overall DF more than 1, 000 for boron.

• Nuclear Engineering and Technology
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• v.19 no.2
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• pp.99-106
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• 1987

Comparison study on the radiological effects by radionuclides from hypothetical 1,000MWe coal-fired power station and nuclear power plant is made. This paper describes the radiological effects only for gaseous effluents released in normal operation. Source terms for coal-fired Power station are quoted from foreign data and those for nuclear power plant are calculated for reference power plant. Gaussian plume model is used to assess atmospheric dispersion of radioactive effluents based on one year meteorological data of Kori site and individual doses are calculated at the maximum X/Q point. Doses from nuclear power plant are slightly more than those from coal-fred power plant. In the case of coal-fired power plant, doses by ingestion of contaminated vegetation are 73.5% of total doses.

• Journal of the Korea Society of Computer and Information
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• v.16 no.12
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• pp.93-102
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• 2011

This paper presents a walking guidance system for blind pedestrians in an outdoor environment using just one single camera. Unlike many existing travel-aid systems that rely on stereo-vision, the proposed system aims to get necessary information of the road environment by using just single camera fixed at the belly of the user. To achieve this goal, a top-view image of the road is used, on which obstacles are detected by first extracting local extreme points and then verified by the polar edge histogram. Meanwhile, user motion is estimated by using optical flow in an area close to the user. Based on these information extracted from image domain, an audio message generation scheme is proposed to deliver guidance instructions via synthetic voice to the blind user. Experiments with several sidewalk video-clips show that the proposed walking guidance system is able to provide useful guidance instructions under certain sidewalk environments.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.229-229
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• 2004

원자력발전소에서 원자로 냉각재 중의 용존산소 제어는 원자로 냉각재 계통에서의 전면 부식과 다양한 형태의 응력부식균열(SCC)를 완화시키는데 기여한다. 원자로 냉각재 계통내에 용존 되어있는 산소는 발전소 기동 시에는 하이드라진($N_2H_4$)을 넣거나 인위적 배기를 통해 제거하고, 정상운전 중에는 체적제어탱크(VCT)에 수소를 가압하여 제거시킨다. 계통내로 유입되는 용존산소를 최대한 억제하기 위하여 대부분의 원자력발전소는 원자로 보충수 탱크 상층부에 질소를 주입하여 탱크로 유입되는 공기를 차단하고 있으나, 이 과정에서 일부 수중에 용해되어 들어가는 질소는 계통 내에서 NH$_3$를 형성하여 화학체적제어계통(CVCS)의 이온교환 수지탑에 치환됨으로서 기포화 되어있는 Li을 계통으로 빠져나오게 하여 계통 pH에 영향을 미친다.(중략)

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2009.11a
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• pp.331-332
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• 2009

본 연구에서는 공학규모 카드뮴 증류장치를 개발하기 위하여 실험실 규모의 수직형 카드뮴 증류장치를 제작하고, 이를 시운전하였다 공탑 실험에서는 증류탑에 온도분포를 잘 조절할 수 있었으며, 응축조의 냉각성능의 보완이 필요하였다. 이 장치를 이용하여 카드뮴 금속의 증류실험을 수행하였으며, 향후 차드뮴-우라늄 합금의 증류거동을 조사할 계획이다.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05d
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• pp.88-94
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• 1996

원자력발전소의 공조계통에 설치되어 운영되는 기체 방사성물질 제거용 첨착 활성탄 탑내에서 균일한 공기 유속분포가 유지되고 있는지를 확인하기 위한 실험을 실시하였다. 본 실험에 사용되는 장비(Tester for Flow Distribution, 이하 TFD라 함)는 원자력발전소에서 사용하는 첨착 활성탄 필터(Adsorber)내의 흡착층을 모방하여 자체에서 제작하였으며, 시험조건들은 실제의 값을 기준으로 적용하였다. 각 위치에서의 보정된 용적 유속을 구하기 위해 자체에서 만든 "FLOWD"라는 계산프로그램을 사용하였으며, 입구 및 출구측 공간에 10" 간격으로 각 6개씩 유속 감지기를 설치하여 면속도를 구하였다. 각 지점에서의 면속도는 평균 0.24449m/s로 각 구간에서의 겉보기 면속도의 분포는 매우 균일한 값을 나타내었으며, 약 2% 이내의 편차로 활성탄 탑내에서의 공기의 흐름이 균일하게 통과함을 확인할 수 있었다.통과함을 확인할 수 있었다.

• Economic and Environmental Geology
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• v.35 no.4
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• pp.355-368
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• 2002

The multi-storied Daewonsa stone pagoda (Treasure No. 1112) in the Sancheong, Korea was studied on the basis of deterioration and geological safety diagnosis. The stone pagoda is composed mainly of granitic gneiss, partly fine-grained granitic gneiss, leucocratic gneiss, biotite granite and ceramics. Each rock of the pagoda is highly exfoliated and fractured along the edges. Some fractures in the main body and roof stones are treated by cement mortar. This pagoda is strongly covered with yellowish to reddish brown tarnish due to the amorphous precipitates of iron hydroxides. Dark grey crust by manganese hydroxides occur Partly, and some Part coated with white grey gypsum and calcite aggregates from the reaction of cement mortar and rain. As the main body, roof and upper part of the pagoda, the rocks are developed into the radial and linear cracks. Surface of this pagoda shows partly yellowish brown, blue and green patchs because of contamination by algae, lichen, moss and bracken. Besides, wall-rocks of the Daewonsa temple and rock aggregates in the Daewonsa valley are changed reddish brown color with the same as those of the pagoda color. It suggests that the rocks around the Daewonsa temple are highly in iron and manganese concentrations compared with the normal granitic gneiss which color change is natural phenomena owing to the oxidation reaction by rain or surface water with rocks. Therefore, for the attenuation of secondary contamination, whitening and reddishness, the possible conservation treatments are needed. Consisting rocks of the pagoda would be epoxy to reinforce the fracture systems for the structural stability on the basements.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.3
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• pp.299-311
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• 2019

Decommissioning is a critical issue in Korea. Although compared with the operation of nuclear power plants the release of radioactive materials during decommissioning is not expected to be significant, residents should always be protected from radiation exposure. To manage this effectively, Annual Release Objectives (ARO) and Annual Release Limits (ARL) were derived from dose standards in the NSSC Notice and dose limit for the public. Based on meteorological data for the three years from 2008 to 2010 in the Shin Kori nuclear power plant site, atmospheric dispersion and ground deposition factors of gaseous effluent were evaluated using the XOQDOQ computer code. The exposure dose was evaluated using the ENDOS-G computer code. Because of differences in radiological sensitivity according to age groups, the results of Annual Release Objectives (ARO) and Annual Release Limits (ARL) showed significant differences depending on the radionuclides. The evaluation methodology of this study will provide meaningful information for radioactive effluent management for decommissioning of nuclear power plants.

• Journal of the Korean Institute of Rural Architecture
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• v.11 no.1
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• pp.25-36
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• 2009

Coastal village and Inland village was village in jeju. This study was cultural elements of stone to village in jeju. Memorial Stone and Stone Monument Street, Shrine, An altar of sarificial site for village tutelary spirits, Bangsatap(pagoda), 25 Bongsu(25 beacon fire stations) and 38 Yeondae(38 signaling sites), Hwanhaejangseong Fortress, Grave wall and Horse pasture walls were included in elements of history and culture to village in jeju. An altar of sarificial rite for village tutelary spirits was generally on the a hill near a village, built of Stone wall. Bangsatap(pagoda) was the kind and the size of stone to a location, that expresses the form and the scale. the form of grave wall was the oval or the rectangle, the latter was frequent. Thatched houses in jeju and facilities in a house, Stone wall, Tongsi(pigsty), Paeng namu and A heights of stone, Spring water and Water collected in a depression, Stone Weir, Horse mill and Dodaebul(Old Lighthouse) were included in elements of life and culture to village in jeju. Stone wall has the multiplicity of the size and the building method in the use, the function and the region. The form of Stone weir was the rectangular figure or the curvilinear figure, the section of that was the right triangle or the rectangular form.