• Title/Summary/Keyword: 방사량

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On decrease program of Radioactive Wastewater and Sewages in High Dose Radioiodine Therapy Ward (고용량 방사성옥소 치료병실의 오.폐수 저감화를 위한 연구)

  • Ryu, Jae-Kwang;Jung, Woo-Young;Shin, Sang-Ki;Cho, Shee-Man
    • The Korean Journal of Nuclear Medicine Technology
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    • v.12 no.1
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    • pp.19-26
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    • 2008
  • Purpose: In general, We discharged radioactive wastewater and sewages less than $8.1{\times}10^{-13}$ Ci/ml in a exclusive water-purifier tank. Our hospital operating three exclusive water-purifier tank for radioactive wastewater and sewages of 60 tons capacity respectively. In order to meet the criteria it need a enough decay more than 125 days per each exclusive tank. However, recently we fell into the serious situation that decay period was decreased remarkably, owing to the wastewater amount increased rapidly by enlarge the therapy ward. For that reason, in this article, I'd like to say the way that reducing of radioactive wastewater and sewages rationally. Materials and Methods: From January, 2006 to October, four hundred and two cases were analyzed. They were all hospitalized during 3 days and 2 nights. We calculated the average amount of water used (include toilet water used, shower water used, washstand water used, $\cdots$), each exclusive water-purifier tank's decay period, as well as try to search the increased factors about water-purifier tank inflow flux by re-analysis of the procedure of radioisotope therapy step by step. Results: We could increase each exclusive water-purifier tank's decay period from 84 days to 130 days through the improvement about following cause: (1) Improvement of conventional toilet stool for excessive water waste $\rightarrow$ Replacement of water saving style toilet stool (2) Prevention of unnecessary shower and wash (3) Stop the diuretics taking during hospitalization (4) Analysis of relationship between water intakes and residual dose of body (5) Education about outside toilet utilization before the administration (6) Changed each water-purifier tank's maximum level from85% to 90% Conclusion: The originality of our efforts are not only software but hardware performance improvements. Incidentally the side of software's are change of therapy procedures and protocols, the side of hardware's are replacement of water saving style toilet stool and change of each water-purifier tank's maximum level. Thus even if a long lapse of time, problem such as return to the former conditions may not happen. Besides, We expect that our trials become a new reasonable model in similar situation.

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The Neutron Dose Estimation of Hot Cell Shield Wall (핫셀 차폐벽의 중성자 선량평가)

  • 조일제;주준식;국동학;구정회;정원명;유길성;이은표
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2003.11a
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    • pp.228-228
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    • 2003
  • 차세대관리 종합공정에서 취급되는 기준 방사선원은 경수로에서 배출된 우라늄-235 농축도 3.5 wt%, 연소도는 43 Gwd/tU 이며 냉각기간은 10년인 사용후핵연료이다. 사용후핵연료의 기준 사양과 차세대관리 종합공정의 특성에 따라 최대 1,385 TBq의 방사선원이 핫셀내에 존재하게 되며, 핫셀 차폐벽은 총 방사능량에 대한 차폐능을 가져야 한다. 최대 방사선원에 대한 핫셀 차폐벽의 중성자에 대한 차폐능을 평가하기 위하여, 본 연구에서는 ORIGEN-2 코드를 이용하여 사용후핵연료에서 발생하는 핵종 및 핵종량을 평가하였으며, 이 자료를 기초로 하여 중성자 선원항을 SOURCES코드를 이용하여 계산하였다.

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A Study on the Prediction of HLW Temperature from Natural Ventilation Quantity using CFD (전산유체학을 이용한 고준위 방사성 폐기물 처분장의 자연환기량에 의한 온도예측)

  • Roh, Jang-Hoon;Yu, Yeong-Seok;Jang, Seung-Hyun;Park, Seon-Oh;Kim, Jin
    • Tunnel and Underground Space
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    • v.22 no.6
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    • pp.429-437
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    • 2012
  • This study predicted temperature in the disposal tunnels using computational fluid dynamics based on natural ventilation quantity that comes from high altitude and temperature differences that are the characteristics of high level waste repository. The result of the previous study that evaluated quantitatively natural ventilation quantity using a hydrostatic method and CFD shows that significant natural ventilation quantity is generated. From the result, this study performed the prediction of temperature in disposal tunnels by natural ventilation quantity by the caloric values of the wastes, at both deep geological repository and surface repository. The result of analysis shows that deep geological repository is effective for thermal control in the disposal tunnels due to heat transfer to rock and the generation of sufficient natural ventilation quantity, while surface repository was detrimental to thermal control, because surface repository was strongly affected by external temperature, and could not generate sufficient natural ventilation quantity. Moreover, this study found that in the case of deep geological repository with a depth of 200 m, the heatof about $10^{\circ}C$ was transferred to the depth of 500 m. Thus, it is considered that if the high level waste repository scheduled to be built in the country is designed placing an emphasis on thermal control, deep geological repository rather than surface repository is more appropriate.

Predictive Efficacy of Radioisotope Voiding Cystography for Renal Outcome (방사성동위원소 배뇨방광촬영술의 신장예후 예측성능)

  • Kim, Seok-Ki;Lee, Dong-Soo;Kim, Kwang-Myeung;Choi, Whang;Chung, June-Key;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.34 no.2
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    • pp.135-143
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    • 2000
  • Purpose: As vesicoureteral reflux (VUR) could lead to renal functional deterioration when combined with urinary tract infection, we need to decide whether operative anti-reflux treatment should be performed at the time of diagnosis of VUR. Predictive value of radioisotope voiding cystography (RIVCG) for renal outcome was tested. Materials and Methods: In 35 children (18 males, 17 females), radiologic voiding cystoure-thrography (VCU), RIVCG and DMSA scan were performed. Change in renal function was evaluated using the follow-up DMSA scan, ultrasonography, and clinical information. Discriminant analysis was performed using individual or integrated variables such as reflux amount and extent at each phase of voiding on RIVCG, in addition to age, gender and cortical defect on DMSA scan at the time of diagnosis. Discriminant function was composed and its performance was examined. Results: Reflux extent at the filling phase and reflux amount and extent at postvoiding phase had a significant prognostic value. Total reflux amount was a composite variable to predict prognosis. Discriminant function composed of reflux extent at the filling phase and reflux amount and extent at postvoiding phase showed better positive predictive value and specificity than conventional reflux grading. Conclusion: RIVCG could predict renal outcome by disclosing characteristic reflux pattern during various voiding phases.

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Relationship between Groundwater Level Changes and Aquifer Characteristics during Pumping at a Radial Collector Well (방사형 집수정 취수시 대수층 특성에 따른 지하수위의 변화)

  • Choi, Myoung-Rak;Lee, Ho-Jeong;Kim, Gyoo-Bum
    • The Journal of Engineering Geology
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    • v.29 no.3
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    • pp.279-288
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    • 2019
  • The groundwater drawdown at each monitoring well near a radial collector well along Anseong Stream, Korea, was measured and compared with the calculated drawdown using the mirror well concept. The drawdown calculation is performed by treating the collector well as a large vertical well in a homogeneous isotropic aquifer. The measured drawdown at each monitoring well is slightly different from the calculated value due to anisotropy in the hydraulic conductivity and aquifer thickness. The difference between the measured and calculated values at Well OW-7 is large, reaching approximately 48 cm, because a horizontal well is not installed along this direction. Sensitivity analysis of the hydraulic conductivity and aquifer thickness indicates that the hydraulic conductivity is more sensitive to groundwater level changes. Groundwater level changes become a concern when a radial collector well with a large pumping rate capacity is installed, which highlights the need to thoroughly investigate the aquifer characteristics in the surrounding area.

Practical Radiation Safety Control: (II) Application of Numerical Guidance for the Discharges of Radioactive Gaseous and Liquid Effluents (방사선안전관리 실무: (II) 배기중 및 배수중 배출관리기준의 적용)

  • Kim, Hyun Kee
    • Journal of Radiation Protection and Research
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    • v.39 no.1
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    • pp.61-64
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    • 2014
  • Radioactive materials are in use and have many applications from the generation of electricity to the purposes of research, industry and medicine such as diagnosis and therapy. In the course of their use some of radioactive substances may be discharged into the environment from facilities using the unsealed radioactive materials, which are main artificial sources occurring the public exposure. Discharges are in the form of gases, particles or liquids. This paper provides procedures to estimate the level of the public exposure based on the conservative assumptions and simple calculations in the facility using unsealed liquid sources. They consist of two processes; (1) to calculate maximum concentration of gaseous effluents discharged through the exhaust pipe and average concentration of liquid effluents discharged through the drain of the storage tank, (2) to compare each of them to numerical guidances for the discharges of radioactive gaseous and liquid effluents mentioned in the related notification. For this purpose followings are assumed properly; daily usage, form and dispersion rate of radionuclides, daily amount of radioactive liquid waste and exhaust and drainage equipment. The procedures are readily applicable to evaluate environmental effects by planned effluent discharges from facilities using the unsealed radioactive materials. In addition they may be utilized to obtain practical requirements for radiation safety control necessary for the reductions of the public exposure.

Measuring external Radiation dose Ratio by Traits of Patients during Positron Emission Tomography(PET) (양전자단층촬영(PET)시 환자의 특성에 따른 외부 방사선량률 측정)

  • Cho, Yong-Gwi;Kim, Sung-Chul;Ahn, Sung-Min
    • The Journal of the Korea Contents Association
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    • v.13 no.12
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    • pp.860-868
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    • 2013
  • The purpose of this study is to ensure safety by measuring External radiation dose ratio (ERDR) by traits of patients in many ways after administering radiopharmaceutical($^{18}F$-FDG) for PET Torso scan, and to decrease ERDR of those to RI technologist, caretakers, and those who frequently exposed to radiation by arousing attention to radiation dose. Radiopharmaceutical was administered to 80 patients who conducted PET Torso from January to June, 2013. Radiation dose emitted from the patients was measured according to body shape(BMI), water hydration, height, amount of radiation administration. From the moment immediately after the radiopharmaceutical was administered, ERDR was measured by personal traits of patients. The radiation dose increased in proportion to the administered amount of the radiopharmaceutical, and there was no significant difference depending on the body shape of the patients. When water was supplied and the height was normal, the radiation dose was lower compared with the cases where water was not supplied and height was not normal. There is a need for making efforts to minimize the working time through sufficient education and mock training before those who RI technologist with sources of radiation for complying the radiation safety management rule. And they should minimize the ERDR by wearing a protective gear.

문화속의 과학 - 문화재의 연대 측정

  • Gang, Byeong-Tae
    • The Science & Technology
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    • v.32 no.2 s.357
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    • pp.11-11
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    • 1999
  • 문화재의 연대를 측정할 때 널리 사용하고 있는 방법은 방사성탄소측정법인데 탄소를 함유하고 있는 유기물(목재,목탄,뼈,패각류 등)을 대상으로 연대를 측정한다. 그런데 최근에는 기기의 발달로 방사성탄소의 개수를 직접 헤아려서 연대를 측정하는 가속기질량분석계를 사용하고 있다.

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