• Nuclear Engineering and Technology
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• 제54권9호
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• pp.3225-3234
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• 2022

Alloy 690 tubing has been shown to be highly resistant to primary water stress corrosion cracking (PWSCC). Nevertheless, predicting the failure by PWSCC in Alloy 690 SG tubes is indispensable. In this work, a Bayesian-based statistical approach is proposed to predict the occurrence of failure by PWSCC in Alloy 690 SG tubing. The prior distributions of the model parameters are developed based on the prior knowledge or information regarding the parameters. Since Alloy 690 is a replacement for Alloy 600, the parameter distributions of Alloy 600 tubing are used to gain prior information about the parameters of Alloy 690 tubing. In addition to estimating the model parameters, analysis of tubing reliability is also performed. Since no PWSCC has been observed in Alloy 690 tubing, only right-censored free-failure life of the tubing are available. Apparently the inference is sensitive to the choice of prior distribution when only right-censored data exist. Thus, one must be careful in choosing the prior distributions for the model parameters. It is found that the use of non-informative prior distribution yields unsatisfactory results, and strongly informative prior distribution will greatly influence the inference, especially when it is considerably optimistic relative to the observed data.

• 한국환경과학회지
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• 제18권6호
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• pp.683-690
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• 2009

The water quality of reservoir can be controled by water quality prediction model because it can not only grasping the present water state but also predicting the water quality in future. In this study, WASP model is used to predict the water quality of Chungju reguration reservoir. This model has some special option which predicts the pollutant outflow phenomenon caused by the contamination sources. So this model is widely used because that can present the scientific basis in this field. This model can help the managers make the right choice of water quality policy. Environmental grade of Chungju reguration reservoir is in III,IV grade which is in bad condition comparatively. The water contamination will be in poor as the year passes. When considering T-N, T-P which are the nutrient to control eutrophication, the concentrated administration about contamination sources is in urgent.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2013년도 추계학술대회
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• pp.988-991
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• 2013

낙동강 하류 지역에는 합천 창녕보, 창녕 함안보, 낙동강하굿둑 좌안배수문 그리고 우안배수문의 수자원시설이 건설되어 운영되고 있다. 원거리에 위치한 각각의 시설물을 연계하여 통합 운영하는 것은 국가 수자원의 관리와 설비 운영의 효율과 효과 측면에서 중요하다. 이러한 이유로 ICT 기술을 활용하여 개별 시설물을 유기적으로 운영할 수 있는 시스템 구현을 계획하고 실행하였다. 부산 낙동강하굿둑 인근에 위치한 K-water 낙동강통합물관리센터에서 개별 시설들을 통합 운영할 수 있는 시스템을 구축하여 효율적인 수자원관리와 운영비용 절감 등의 상당한 기대효과가 있을 것으로 사료된다.

• 수산해양기술연구
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• 제38권1호
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• pp.69-78
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• 2002

In order to examine the directional suitability of the axis direction of the fishing gear against the current, the experiments were carried out at the bamboo weir in Samchunpo water area from January, 2000 to September, 2001 The results of the study are as follows: In the experimental fishing gear constructed in the "V" shape, the range between two reference piles located at the entrance was 2.5m. The direction of bamboo weir′s axis was 355.5$^{\circ}$ The length of the left wing and those from the reference pile to the starting point of a curve were 106.0m, 7.5m, respectively. The length of the right wing and those from the reference pile to the starting point of a curve were 79.0m, 10.0m, respectively. Depths around the left and right stone wall that drove the steel pile were 5.0~6.5m and 6.5~9.5m, respectively. Also, depths on the bamboo weir′s axis and around the sack were 7.0~8.0m and about 8.0m, respectively. The maximum height of stone walls at the point of the left wing, the right wing and around the sack on the bamboo weir\` axis were 3.0m, 4.7m and 4.0m, respectively, Widths of stone walls at the point of both of the wings and around the sack on the bamboo weir\`s axis were 10.0~l4.0m, 22.0~25.0m, respectively. The averaging current direction on ebb tide was measured two times and it was 169.2$^{\circ}$ but the direction had about a 6.3$^{\circ}$ difference from the bamboo weirs axis. The maximum current speed appeared two to three hours later from the time of high tide and the current speed over 80.0cm/s lasted during about two Hours on the ebb tide In the case of a straight type wing In the bamboo weir, the eddy out of the left wing was comparatively big and the current on the right side from the bamboo weir′s axis had a tendency in turning to the right wing side. But in the case of a curve type wing, the eddy and tendency reduced significantly. It was thought that the experimental fishing gear was set suitably from the result of this simulation.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 1992년도 수공학연구발표회논문집
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• pp.133-141
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• 1992

A three water-intake structure designed to built along the right bank of the Missouri River near Chesterfield, Missouri was model-tested at an undistorted scale of 1:5. Although the discharge capacity of each of six pumps to be installed is only 21,000 gpm, the model indicated strong flow circuation and unstable free-surface conditions as flow entered the two-pump bay through a narrow sluice opening at an angle. Strong free-surface vartices were also observed in the model. The sump modifications developed in the study included an array of baffle bars, a perforated plate, floor splitters, and floor-corner fillets. The solutions developed in this study could be applied to other pump sumps with multiple pump units.

• Water Engineering Research
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• 제2권3호
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• pp.161-169
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• 2001

Present study deals with the development of a numerical model for the estimation of net annual recharge by coupling the Galerkin's finite element flow simulationl model with the Gauss-Newton-Marquardt optimization technique. The developed coupled numerical model is applied for estimating net annual recharge for Mahi Right Bank Canal (MRBC) project the norms of Groundwater Resources Estimation committee (1984, 1997) and Indian Agricultural research Institute(1983). It is observed that the estimated net recharge by inverse modeling is closer to the net recharge estimated using the water balance approach. Further it is observed that the computed head distribution from the estimated recharge agree closely with the observed head distribution. The study concludes that the developed model for inverse modeling can be successfully applied to large groundwater system involving regional aquifers where reliable recharge estimation always requires considerable time and financial resources.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.17-20
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• 2002

Hasa TM/TC system is composed of one control center, two reservoirs, six pumping stations and twelve canal systems. For this system we developed water management program which includes flood forecast program, drought reduction program, irrigation scheduling program and database program. With these program we expect that operators can improve the irrigation efficiencies of the irrigation systems due to the timely irrigation on a right place, in a proper quantity and reduce the cost of maintenance and reduce flood and drought damages of the Hasa district. In agricultural engineering respect, the databases including water level, rainfall, the amount of flowing can be useful to the researcher who make a study of hydrology and hydraulics in rural area. Water management program records all of the TM/TC data to MOB format file per 10 minutes.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.69-73
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• 2001

At this project we developed water management program for sungju district. This program include flood forecast program, drought reduction program, irrigation scheduling program and database program. With these program we expect that operator can improve the irrigation efficiencies of the irrigation systems due to the timely irrigation on a right place, in a proper quantity and reduce the cost of maintenance. In agricultural engineering respect, the databases including water level, rainfall, the amount of flowing can be useful to the researcher who make a study of hydrology and hydraulics in rural area, Water management program record all of the TM/TC data to MDB format file per 10 minutes.

• 상하수도학회지
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• 제11권2호
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• pp.31-39
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• 1997

Between 40,000 and 60,000 liters of light oil were spilled when an underground pipe broke at a newly constructed landfill site in coastal area, Korea. Methods were presented to examine the subsurface distribution of the contaminants in hydrocarbon-contaminated soil. As results, large quantities of oil and grease were found to have migrated horizontally at the site. Oil and grease plume at concentrations of 38-88 mg/kg was formed horizontally through silty sand with gravel fill and the vertical movement of the contaminants was thought to be limited to groundwater level between 2 and 4 m corresponding to sea water level. Right after finding the leakage area, the early action of excavation and pumping out the mixture of groundwater and oil was taken and it was proved to be very effective for preventing further contamination. Two months after the leakage, oil and grease in sea water sample near contaminated area was not detectable.

• 한국동물위생학회지
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• 제36권4호
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• pp.321-325
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• 2013

A mass of the adrenal gland was observed during a routine necropsy of a female 23-year-old Asian Water Buffalo (Bubalus bubalis) at Seoul Zoo in Gyeonggi Province, Korea. The animal showed no clinical signs but the necropsy examination revealed hydropericardium, ascites, hydrothorax and edema of the intestinal wall, lung and adrenal gland. Histopathologically, the neoplastic cells of the right adrenal gland were arranged in lobules supported by a fine fibrovascular stroma. The neoplastic cells had round hyperchromatic nuclei and granular eosinophilic to basophilic cytoplasm. Immunohistochemically, tumor cells were positive for chromogranin A and S-100 and negative for vimentin, synaptophysin and cytokeratin. Based on the above findings, this case was diagnosed as a pheochromocytoma. To the best of our knowledge, this is the first report of a pheochromocytoma in an Asian Water Buffalo (Bubalus bubalis).