• 한국소음진동공학회논문집
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• 제19권10호
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• pp.1043-1052
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• 2009

In this work, a master-slave manipulator system which will be used for handling objects contaminated by radioactivity has been addressed. The links of manipulators are driven independently by individual motors installed on the base and the driving torque is transmitted through pre-tensioned tendons. Since the measurable variables are the positions and rates of master/slave motors, only a constrained specific bilateral control structure is available. In the consideration of the flexibility of the tendon and constrained control structure, we derived a necessity for tendon design to prevent uncontrollable vibration mode through a modal analysis. Based on a reduced rigid body model, a control design was suggested and tendons were selected. The feasibility of the proposed analysis and tendon design were verified along with some simulation results.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.28-31
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• 2006

It is require to construct geothermal database to develop geothermal energy as renewable energy policy. It must be consist of geologic data, borehole data and geophysical data for geothermal database. In aspect of geology, there are included the distribution of geology, structural geology, geological time, rock name, density of rock, porosity, thermal diffusivity, specific capacity and thermal conductivity In order to calculate the heat general ion, it is needed to analysis the radioactivity elements as U, Th and K of rock. In aspect of borehole data, there are included temperature of depth, surface temperature and geothermal gradient And also there is geotherrnornetry using chemical components of groundwater as Na Ca, K and $SiO_2$. In aspect of geophysical data, there are some thematic map as booger gravity anomaly data and magnetic survey data and etc. In addition, it is important to descript the distribution of hot spring and water temperature.

• Nuclear Engineering and Technology
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• 제2권3호
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• pp.179-183
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• 1970

Solanum andigena의 광주성 주기중의 방사성 콜레스테롤의 대사를 연구하였다. 대사산물로서 방사성 솔라닌과 그 가수분해물 솔라니딘을 분리 결정화하였으며, 콜레스테롤은 이 식물체 내에서 형성되는 에스테르화된 형태로 분리하였다. 단일 및 장일식물간의 콜레스테롤을 대사에는 뚜렷한 차이는 찾아 볼 수 없으나. 괴경중의 스테로이드 알카로이드에 콜레스테롤이 관여하고 있는 것으로 논의되었다.

• 한국동물학회지
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• 제3권1호
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• pp.19-23
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• 1960

A method for determination of thyroid secretion rate in rabbit by means of radioactive iodine presented. After injection of radioactive iodine, in vivo determination so f radioactivity in thyroid gland were made during a 19 day-experimental period. In the same period blood samples were drawn and analyzed for protein-bound iodine (PBI) and for protein-bound radioactive iodine(PBI181). A rate constant for secretion of thyroid hormone was calculated from the disappearance rate of radioactive iodine in thyroid gland. The secretion rate of radioactive hormone iodine was calculated by multiplying this rate constant by the amount of radioactive iodine present in thyroid gland. Assuming that the specific radioactiveness of the circulating thyroid hormone and of the hormone just secreted were identical , thyroid secretion rate was calculated by the equation. {{{{ { Secreted hormone-iodine , gamma /hr} over { Secreted hormone-I^131, % dose/hr }= { PBI, ${\gamma}$/ml.Serum} over { PBI^131 , % dose/ml . Serum } }} The method presented consisted of measurements for series of independent criteria on thyroid function, and the resulting thyroid secretion rate was calculated by combination of those.

• Journal of Ginseng Research
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• 제21권1호
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• pp.19-27
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• 1997

The present study was conducted to assess the effect of total saponins from Korean red ginseng on the biosynthesis of inositol phospholipids in vivo and also effects on the metabolic enzymes, such as phosphatidylinositol-specific phospholipase C(Pl-PLC) and PI-kinases. The administration of 0.1% saponin solution, 0.1 ml 3 times a day intraperitoneally to 5 mice for 30 days has increased a 23% of the body weight when it compared with a control group. The amounts of 32P-phoschorus radioactivity incorporated into the phosphoinositides from the liver and brain tissues have increased a 310% and 260%, respectively, in the saponin treated mice. The activities of PI-PLC from liver and brain were stimulated in the various amounts by the conditions treated with saponins. The PI-kinases from liver and brain were also activated by saponins, but its effect was lower than that of PI-PLC. From these results, it was confirmed that red ginseng saponins have affected positively not only on the biosynthesis of phosphoinositides but also on the PI-PLC and PI-kinases related to the cellular signal transduction.

• Nuclear Engineering and Technology
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• 제37권4호
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• pp.327-362
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• 2005

The design, construction, and operation of a light water reactor (LWR) are subject to compliance with safety criteria specified for accident situations, such as loss-of-coolant accident (LOCA) and reactivity-initiated accident (RIA). Because reactor fuel is the primary source of radioactivity and heat generation, such a criterion is established on the basis of the characteristics and performance of fuel under the specific accident condition. As such, fuel behavior under accident situations impact many aspects of fuel design and power generation, and in an indirect manner, even spent fuel storage and management. This paper provides a comprehensive review of: the history of the current LOCA criteria, results of LOCA-related investigations on conventional and new classes of fuel, and status of on-going studies on high-burnup fuel under LOCA situations. The objective of the paper is to provide a better understanding of important issues and an insight helpful to establish new LOCA criteria for modem LWR fuels.

• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2652-2660
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• 2021

The gamma-ray exposure doses in decontamination operation after a nuclear accident were evaluated with a consideration of various geometrical conditions and specific gamma-ray energies. The calculation domain is organized with three residence types and each form is divided into two kinds of geometrical arrangements. The position-wise air KERMA values were calculated with an assumption of evenly distributed gamma-ray source based on Monte Carlo radiation transport analysis using the MCNP code. The radioactivity is initially set to be unity to be multiplied by the deposition value measured in the actual accident condition. The workforce data set depending on the target object was determined by modifying the Fukushima report. The external exposure doses for decontamination workers were derived from the calculated KERMA values and the workforce analysis. These results can be used to efficiently determine the workforce required by the characteristics of the area and the structure to be decontaminated within the dose limits.

• 한국지하수토양환경학회지:지하수토양환경
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• 제14권2호
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• pp.10-16
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• 2009

감마선 분광법을 이용하여 금강유역에 분포되어 있는 7개 기반암 지역 토양의 자연방사능 특성을 조사하였다. 우라늄계열 $^{226}$Ra, 토륨계열의 $^{228}$Ac과 비계열 핵종인 $^{40}$K와 같은 대표적인 자연방사성핵종(naturally occurring radioactive nuclide)의 비방사능 (specific activity:SA, Bq/kg)을 측정하고 비방사능 비(specific activity ratio:SAR)를 산출하여 기반암에 다른 토양에 대한 자연방사능 특성을 분석하였다. 7개 기반암지역 41지점 토양에서의 SA값은 $^{226}$Ra의 경우는 26.7-485(74.2 ${\pm}$ 72.2)Bq/kg, $^{228}$Ac은 30.9-157(90.7${\pm}$32.7) Bq/kg, 그리고 $^{40}$K는 203-1588(990${\pm}$203)Bq/kg으로 나타났다. 기반암 특성별 가장 큰 차이를 보이는 핵종은 $^{226}$Ra이었으며 특히 캠브리아기 변성퇴적암 기원의 한 지점에서는 485Bq/kg으로 평균값이 74.2Bq/kg인 다른지점들의 토양과 큰 차이를 보이고 있다. $^{226}$Ra보다는 적지만 $^{228}$ Ac의 SA값도 기반암에 다라서 다소 특성을 보이고 있었으나, $^{40}$K의 SA값의 경우는 특이한 차이가 없는 것으로 나타났다. 세 핵종간의 SAR은 $^{226}$Ra/$^{228}$Ac은 0.343-6.11(0.865${\pm}$0.883), $^{226}$Ra/$^{40}$K는 0.0258-0.759(0.0814${\pm}$0.1117),그리고 $^{228}$Ac/$^{40}$K는 0.0373-0.178(0.0945${\pm}$0.0373)로 세 핵종의 SA 특성에서 예견할 수 있었던 것과 같이 $^{226}$Ra/$^{228}$Ac, $^{226}$Ra/$^{40}$K의 SAR 특성은 토양에 다라서 얼마간 보이는 반면 $^{228}$Ac/$^{40}$K는 별다른 특성을 보이지 않았다.

• 분석과학
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• 제21권6호
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• pp.474-479
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• 2008

중국의 주요 황사발원지로 알려진 오도스 사막, 알라샨 사막, 타클라마칸 사막 및 황토고원의 표층퇴적물에 분포되어 있는 우라늄계열의 $^{226}Ra$, 토륨계열의 $^{228}Ac$과 비 계열인 $^{40}K$과 같은 지각중 대표적인 자연방사성핵종의(naturally occurring radioactive nuclide: NORN) 방사능 특성을 조사하였다. 감마선 분광법을 이용하여 NORN의 비방사능(specific activity: SA, Bq/kg)을 측정하고 비방사능 비(specific activity ratio: SAR)를 산출하여 발원지에 따른 자연방사능 특성을 분석하였다. 발원지에 따른 세 핵종의 SA값은 $^{226}Ra$의 경우 세 사막지대에서는 평균 17.9~21.9 Bq/kg으로 매우 유사한 값을 가지는 반면 황토고원에서는 평균 35.0 Bq/Kg으로 큰 차이를 나타내고 있었다. $^{228}Ac$의 경우는 오도스 사막과 알라샨 사막에서는 평균 27.1~27.2 Bq/kg으로 거의 같은 값을 가지며 타클라마칸 사막에서는 31.7 Bq/kg 그리고 황토고원에서는 49.0 Bq/kg으로 큰 차이를 나타내고 있었다. $^{40}K$의 경우는 636~943 Bq/kg 으로 네 곳의 발원지에서 특별한 차이를 나타내지 않았다. $^{226}Ra/^{228}Ac$의 평균 SAR 값에서 네 곳의 발원지에서 0.708-0.721로 거의 일정하게 나타났고 $^{226}Ra/^{40}K$과 $^{228}Ac/^{40}K$의 평균 SAR 값을 보면, 오도스와 알라샨 사막은 각각 0.0209-0.0213과 0.0287-0.0320으로 유사한 값을 나타내고 있으나 타클라마칸 사막과 황토고원 표층시료들에서의 평균 SAR 값을 보면, 0.0353, 0.0506과 0.0493, 0.0773으로 상당한 차이를 나타낸다.

• 한국식품영양과학회지
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• 제21권3호
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• pp.241-246
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• 1992

L-Ascorbic acid (AsA) 생합성이 불가능한 guinea pig을 실험 동물로 하여 collagne 함량이 높은 조직인 폐 및 피부중의 AsA함량과 동일조직중 collagne 함량이 높은 조직인 폐 및 피부중의 AsA 함량과 동일조직중 collagen의 proline잔기의 수산화율을 조사하여 collagne 생합성에 대한 조직중 AsA의 영향에 대해서 알아보았다. Guinea pig(체중 약 250g)를 AsA 무투여군(A), 투여군(B), 300mg/day 투여군(C)으로 나눠 14일간 사육한 후, 마취하에서 개복하여 복부 대동맥으로부터 채혈함과 동시에 간장과 폐를 적출하였으며, 등부위의 피부를 채취하여 분석용 시료로 하였다. 이들 시료로부터 혈청중 alkaline phosphatase (ALP)활성과 각조직중의 AsA 함량, proline 함량 및 그 수산화율, (1-$^{14}$ C) proline 의 incorporation 양을 측정하였다. 그 결과, AsA 토여군인 B, C군의 경우 순조로운 체중증가와 함께 혈청중 ALP활성도 정상값을 나타냈으며 현저한 ALP활성 저하가 관찰되었다. 한편, AsA 함량이 높을수록 (1-14C) proline 의 incorporation 양이 많고 collagne 중의 hydroxyproline 함량도 증가하는 것으로 나타나, 조직중의 collagen합성량과 AsA함량과의 사이에는 높은 상관관계가 존재함이 확인되었다.