자연환경방사선에 의한 피폭선량(유효선량당량)의 종합적 해석연구

전재식,채하석,이병영,김현창,이동준,김도성,엄두하 충남대학교 기초과학연구소 1990 연구논문집 Vol.10 No.-

자연환경방사선의 세 가지 주요 요소인 지각방사선, 우주선 전리성분 및 라돈과 그 자핵종이 주는 선량을 측정, 해석하였는 바 18개월간에 걸쳐 대전, 수원, 경산 지역에 대하여 수행하고 이를 종합하여 유효선량당량으로 평가하였다. 지각방사선과 우주선 전리성분 측정을 위하여 3"∮×3" Nal(Tl) 섬광검출기와 휴대형 다중파고분석기를 이용한 감마선 분광분석 및 ^7LiF PTEE disk TLD에 의한 적산선량측정을 병행하였고, 공기중 라돈농도의 측정은 CR-39 고체비적검출기를 내장한 라돈컵을 설계제작하여 사용하였으며 비적수 라돈농도 교정인자는 스웨덴 국립방사선 방호연구소의 표준 라돈 챔버내에서 조사하여 결정하였다. 세 지역의 가연방사선에 의한 유효선량당량에는 약간의 수치적 차이는 있었으나 본질적 차이는 찾아볼 수 없었으며 지역 측정치의 분산가중 평균치는 지각방사선 (463±3)uSvㆍy^-1[(52.9±0.3)nSvㆍh^-1], 우주선 전리성분 (287±15)uSvㆍy^-1[(32.8±1.7)nSvㆍy^-1]로 외부 피폭이 (775±9)uSvㆍy^-1[(88.5±1.0)nSvㆍy^-1]였으며 라돈과 그 자핵종에 의한 내부피폭은 (1973±298)uSvㆍy^-1[(225.2±34.0)nSvㆍy^-1]였다. 따라서 자연황경방사선에 의한 여간 총 선량당량은 (2762±296)uSvㆍy^-1[(315.3±34.0)nSvㆍh^-1]로 평가되었는데 이 값들은 UN보고서^(11)에 나온 “정상적 자연방사선 지역”의 값과 비교할 만한 타당한 값으로 나타났다. Assessment of effective dose equivalent from natural environmental radiation that consists of terrestrial gamma­ray, ionizing component of cosmic­ray and alpha­rays of atmospheric radon and its decay products has been carried out for 18 months in Daejeon, Suwon and Kyungsan areas. A 3"∮×3"cylindrical Nal(Ti) scintillation detector in association with portable multichannel analyser and ^7LiF PTFE disk TLDs were used for the measurement of terrestrial gamma­ray and cosmic­ray ionizing component, while self­designed radon­cups with CR-39 SSNTD attached to the inside bottom were used for the integral measurement of at­mospheric radon concentration. Determination of calibration factor for converting track density of CR-39 detector to radon concentration was made by irradiation of radon­cups in the standard radon chamber of Swedish National Institute of Radiation Protection. Although resultant effective dose equivalents of three different measurment points show minor numerical differences, no essential discripancy between the places was found. The variance weighted means of the annual effective dose equivalents of each component of radiation from the tree places came out to be: (463±3)uSvㆍy^-1[(52.9±0.3)nSvㆍy^-1] for terrestrial gamma­ray, (287±15)uSvㆍy^-1[(32.8±1.7)nSvㆍy^-1] for ionizing component of cosmic­ray and (1973±298)uSvㆍy^-1[(225.2±34.0)nSvㆍy^-1] for internal exposure of radon and its decay products. Consequent total effective dose equivalent turned out to be (2762±298)uSvㆍy^-1[(315.3±34.0)nSvㆍy^-1], which if reasonably comparable with that appeared in UNSCEAR Report^[11]as per caput annual effective dose equivalent in “areas of normal back ground radiation.”

산재보상을 신청한 뇌심혈관질환의 특성 분석

유재홍,하은희,김수근,김정연,김용규,이의철,이철호,손준석 대한산업의학회 2007 대한직업환경의학회지 Vol.19 No.1

목적: 이 연구는 뇌 · 심혈관 질환으로 업무상재해를 신청한 사례 중에서 승인된 사례와 불승인된 사례의 특성을 비교하여 뇌 · 심혈관 질환의 업무상 재해여부를 판단하는데 필요한 기초 자료를 제공하고자 한다. 방법: 2000년부터 2004년까지 근로복지공단에 업무상 재해로 요양이 신청되어 승인여부가 결정된 뇌 · 심혈관 질환자 12,309명을 대상으로 하였다. 승인여부와 관련된 특성을 확인하기 위해 연도별, 업종별, 규모별, 직업별, 성별, 연령별, 질환별, 생존유무별 그리고 기존질환 유무에 대하여 카이제곱 검정과 다변량 로지스틱 회귀분석을 이용하였다. 결과: 다변량 로지스틱 분석에서 뇌 · 심혈관 질환의 불승인에 대한 승인의 비차비는 광업을 기준으로 하였을 때에 전기가스 상수도업이 4.18(95% CI=1.43~12.17), 건설업이 2.39 (95% CI=1.22~4.69), 제조업이 2.10 (95% CI=1.08~4.07)이었고, 장치기계조작원 및 조립원에 비하여 서비스 근로자 및 상점과 시장 판매근로자 군이 1.90(95% CI=1.47~2.47), 전문가 군이 1.83(95% CI=1.50~2.23), 기술공 및 준전문가 군이 1.63(95% CI=1.35~1.97), 입법 공무원과 고위 임직원 및 관리자 군이 1.62(95% CI=1.24~2.12)이었고, 여성이 남성에 비하여 1.31(95% CI=1.13~1.53), 심장질환에 비하여 뇌혈관질환이 2.75(95% CI=2.42~3.13), 사망한 경우가 생존한 경우에 비하여 6.01(95% CI=4.89~7.38)이었다. 결론: 우리나라에서 뇌심혈관질환으로 업무상 재해를 신청하는 건수는 증가하고 있고 승인율은 비교적 높았으며 승인에 영향을 미치는 요인으로는 업종, 규모, 직종, 성, 연령, 질환, 생존유무 등이 확인되었다. 특히 업종과 직종에 따라서 승인율의 차이가 큰 것이 어떠한 요인의 영향 때문인지에 대한 검토가 필요하고, 특히 뇌실질내 출혈의 경우에 다른 질환에 비하여 승인율이 매우 높았던 것은 업무수행성에 대한 인정기준의 잘못된 적용의 결과 이므로 시정이 필요하겠다. Objectives: This study was performed to provide fundamental data to judge whether or not cerebro and cardiovascular diseases are work-related, by comparing the characteristics between approved and non-approved cases among the worker's compensation claims. Methods: We collected 12,309 cerebro and cardiovascular disease claims based on the worker's compensation records of the Labor Welfare Corporation from 2000 to 2004. The approved and non-approved cases were analyzed according to factors such as the calendar year, industry, company size, occupation, gender, age group, classification of cerebro and cardiovascular diseases, fatality and underlying diseases. We used x²-test and multivariate logistic regression for the analysis. Results: According to multivariate logistic regression, electricity gas and water supply (OR=4.18, 95% CI=1.43~12.17), construction (OR=2.39, 95% CI=1.22~4.69) and manufacturing (OR=2.10, 95% CI=1.08~4.07) industries had a higher approval rate than mining and quarrying industries. Service workers and sales & marketing department workers (OR=1.90, 95% CI=1.47~2.47), professionals (OR=1.83, 95% CI=1.50~2.23), technicians and associate professionals (OR=1.63, 95% CI=1.35~1.97) and legislators and senior officials and managers (OR=l.62, 95% CI=1.24~2.12) had a higher approval rate than plant and machine operators and assemblers. Female workers had a higher approval rate (OR=1.31, 95% CI=1.13~1.53) than male workers. Cerebrovascular diseases had a higher approval rate (OR=2.75, 95% CI=2.42~3.13) than cardiovascular diseases. Fatal cases had a higher approval rate (OR=6.01, 95% CI=4.89~7.38) than surviving cases. Conclusion: For cerebro and cardiovascular diseases, workers' compensation claims are increasing, approval rates are relatively high and factors such as industry, company size, occupation, gender and fatality are related. A remarkable difference in the approval rate was found according to industry and occupation, suggesting the need for further study to identify which factors influence the approval rate. The approval rate for intracerebral hemorrhage arising in the course of employment (COE) was significantly higher than that arising out of employment (AOE), suggesting the need to correct the approval criteria.

임신과 동반된 난소섬유난포막종 1례

류은석,김윤숙,전섭,김종수,최승도,선우재근,배동한,양승화 순천향의학연구소 2005 Journal of Soonchunhyang Medical Science Vol.11 No.1

Fibrothecoma are mesenchymal tumors deriving from the ovarian stroma and consisting of theca-like elements and fibrous tissues. The reported incidence is between 0.4 and 8.0% of all ovarian tumors and this side variability can be attributed to the difficulty in differentiation fibrothecoma from ovarian fibroma or hyperplastic stroma nodules. We experienced a rare case of ovarian fibrothecoma in woman at 38 weeks gestation with previous repeat cesarean section diagnosed after tertiary cesarean delivery and bilateral tubal ligation with a brief review of literature.

HPGe 검출기에 의한 지각방사선의 핵분광학적 연구

전재식,채하석,진응국,이철영,조혁,하정우 충남대학교 기초과학연구소 1992 연구논문집 Vol.12 No.-

고순도 Ge(HPGe) 검출장치를 사용한 현장측정을 통하여 지각방사선에 대한 핵분광학적 연구를 수행하였는바 지각방사선장의 핵분광학적 특성차이를 규명하기 위하여 지면의 자연방사성 핵종분포가 대표적 전형인 충남대학교 캠퍼스내 미경작 개활지 잔디밭과, 우라늄 함량이 높은 곳으로 알려진 괴산군 덕평리 지역 등 특이한 두 지역을 측정지점으로 선택하였다. 환산선량의 비교확인을 위하여 HPGe 분광측정은 3″ø×3″원통형 NaI(T1) 섬광검출기에 의한 분광측정과 동시에 수행하였으며 본 연구에 사용된 HPGe 검출기에 대한 스펙트럼-선량율 환산인자 G(E)는 감마선속이 검출기 축에 수직 입사하는 것으로 가정하고 Monte Carlo 방법으로 씨뮬레이션한 감응스펙트럼들을 사용하여 산출하였다. 이 G(E)를 사용하여 산출된 선량율(D˙_Ge)은, 이미 기준기급 전리함과의 비교 교정을 통하여 스펙트럼-선량 환산체계가 확립된 바 있는 NaI(T1) 검출기로 구한 선량율(D˙_NaI)과 만족스러운 일치를 보였으며 D˙_Ge와 D˙_NaI 사이의 상관계수는 +0.9988, 회귀 방정식의 기울기는 1.001을 나타내었다. 측정한 스펙트럼에서는 미미한 크기의 ^137Cs 감마선 피크가 확인되었으나 1960년대에 수행되었던 대기권 핵실험의 영향이나 Chernobyl 원전사고의 영향은 관측되지 않았다. Study of terrestrial gamma-rays was carried out by means of in-situ spectrometry using high purity germanium (HPGe) detector system. Two distinguishable fields of measurements, namely, uncultivated flat lawns in CNU campus where the distribution of natural radionuclides in the ground in known to be quite typical and well-known uranium rich area of Dukpyung-ri in Gwoesan-kun were selected in order to specify the difference in spectrometric characteristics of the fields. In-situ HPGe spectromety was accompanied by scintillation spectrometry with 3″ø×3″cylindrical NaI(T1) detector for comparative confirmation of derived dose rates from the spectra measured. Spectrum-dose rate conversion operator, G(E), of our particular HPGe detector was calculated using response spectra simulated by Monte Carlo method with an assumption of gamma-ray beams incident vertically to the detector axis. Resultant dose rates (D˙_Ge) showed satisfactory agreement with those obtained by NaI(T1) spectrometry and corresponding G(E) operation (D˙_NaI) of which system has been well-established through intercalibration with a reference ion chamber. Correlation coefficient and the slope of regression equation between D˙_Ge and D˙_NaI came out to be +0.9988 and 1.001, respectively. Though traceable height of ^137Cs gamma-ray peak was identified on the field spectrum, ground contamination of fission products released from atmospheric nuclear test performed in 1960s and possibly from Chernobyl accident was not observed as of today.

주혈관이 하나만 남은 하퇴부 연부조직 결손 환자에서 비복혈관(sural vessel)을 수혜혈관으로 한 유리피판 전이

변재경,하범준,현원석,김재중,신명수 大韓成形外科學會 1999 Archives of Plastic Surgery Vol.26 No.3

Free flaps have been widely used in lower leg reconstruction. However, in cases with extensive injury to the vessels as well as to the bone and soft tissues, and having only one intact major vessel in the lower leg(single vessel leg), careful selection of recipient vessels for the free flap transfer is mandatory for preventing further vascular compromise of the distal lower leg. The sural artery and its vena comitantes are frequently protected form externally harmful forces by the bulky surrounding gastrocnemius muscle and can be used as recipient vessles for free flaps without any detrimental influence on the vascularity of the distal lower leg. In our department, three latissimus dorsi muscle free flap were transferred with sural vessels as recipient vessels in the reconstruction of the single vessel legs. Except for one case of flap failure due to serious infection at the microvascular anastomoses site, all the other cases were successfully reconstructed without any necrosis of the gastrocnemius muscle or the distal leg. In addition, the sural vessels were easily accessed in any patient position and their caliber was similar to that of the vascular pedicles of the donor muscle flaps. In conclusion, the sural vessels can be another useful option in selecting recipient vessels for free flap transfer in the reconstruction of the single vessel leg.

도암호의 수질과 어류군집 특성 연구

이상하,최재석,이광열,장영수,임인수,허우명,김재구,김범철 강원대학교 부속 환경연구소 2005 Journal of the Environment Vol.2 No.-

To investigate nutrient dynamics of the lake and fish community, both water and fish samples were collected at three different areas (dam site, upper inflowing and downstream of lake outfow) for one year from Sep.2004 to Aug.2005 During the experimental periods, mean concentration of chl, a in epilimnetic layer (0-5m) was 18.5mg^(-3) and transparency ranged from 0.3m to 2.4m, respectively. In nutrient, mean concentrations of TP and TN were 111 mgP m^(-3) and 4.4 mgN L^(-1), respectively. Based on the water quality standard suggested by U.S.EPA(*1976), the trophic state of Lake Doam was classified as eutrophic state. Total number of fish collected in Lake Doam was 9,600 indiveduals in 26 species of 6 family. Sixteen of Korean endemic soecies including H. mylodon, A. signifer, P. tenuicorpa occurred. O. mykiss as introduced fish was also found in Lake Doam. Dominant and subdominant species were P. herzi and Z. platypus that took about 34.6% and 22.5% of total fish composition, respectively. Six species including A. signifer. P. tenuicorpa. and R. kumgangensis were rare in Lake Doam. Pelagic typw of figh commonly occurred at upper regions, whereas benthic type was mainly domenated at downstream area. Therefore, pollution source inflowed from the upper regions did not seriously affect downstream area (Songcheon water system) due to the role of dam as pollutant barrier. In addition high appearance of Comat type of fish that si hybrid between gold fish (C.auratus) and C. auratus was found in the lake, It was unclear the reasons that high prorortion of mutant species apperared in the lake. Further more researches are required in this area.

고성능 콘크리트 구조의 시간의존적 거동 예측

이재석, 최규천, 박영하 충북대학교 건설기술연구소 2008 충북대학교 건설기술연구소 논문집 Vol.27 No.1

The use of high-performance concrete with low water-cement ratio has been continuously increasing. Time-dependent behaviors of normal and high-performance concrete due to the shrinkage deformations, such as drying shrinkage and autogenous shrinkage, are different. However, time-dependent characteristics of the high-performance concrete are not considered in the design of the domestic concrete structures so far. In this paper, the time-dependent behavior of high-performance concrete structures using the CEB-FIP MC 90 model which is adopted in domestic code and the fib bulletin model can predict the time-dependent behavior of normal as well as high-performance concrete are analyzed. The analysis result of the column and PSC cable-stayed bridge using CEB-FIP MC 90 model and the fib bulletin model, respectively, show that the differences of time-dependent behavior are not negligible.

고체비적 검출기의 라돈 검출 효율 결정을 위한 라돈 챔버 설계제작

채하석,전재식 충남대학교 기초과학연구소 1990 연구논문집 Vol.10 No.-

CR-39 고체비적 검출기를 내장한 라돈컵을 설계제작하고 대기 중 라돈 검출효율을 결정하기 위하여 길이 74㎝, 내부지름 18㎝인 원통형의 라돈 챔버를 투명한 아크릴로 설계 제작하였다. 챔버내에는 라돈컵이 방사평형이 이루어진 후에는 라돈기체에 조사되도록 특별히 설계된 두 개의 라돈컵 지지대를 설치하였다. 라돈기체는 122.1kBq의 라듐이 들어있는 Pylon RN-1025 라돈 발생장치에서 공급되도록 챔버에 연결하였다. 이 챔버의 라돈에 조사시켜 결정된 직접형(CR-39 평면판), 개방컵, 필터컵의 검출효율은 각각(37.2±0.6)×10^-4, (25.3±0.8)×10^-4 및 (16.6±0.5)×10^-4trㆍ㎜^-2/(Bqㆍm^-3ㆍd)로 나타났다. 충남대학교 대덕 캠퍼스내 한 개활지의 1m까지의 여러 높이에서 라돈컵을 사용하여 1989년 6월부터 10월까지 5개월 동안 1개월 간격으로 측정한 공기 중 라돈농도의 평균값은 개방컵과 필터컵에서 측정한 값이 각각 55.6±16.5Bqㆍm^-3, 50.5±26.6Bqㆍm^-3으로 해석되었다. For the determination of atmospheric radon detection efficiency of self­sesigned radon cups equipped with CR-39 solid state nuclear detector. an annular cylindrical calibration radon chamber of 74㎝ in length and 18㎝ in inner diameter was designed and fabricated with transparent acrylic material. Two radon cup holders. which enable the cups to be exposed to controlled radioactively­equilibrated radon gas, were installed in the chamber. This chamber was connected to Pylon RN-1025 radon generator containing 122.1 kBq ^226Ra in order to be provided with radon gas for the calibration of the detectors. Thus determined radon detection efficiencies or calibration factors of bare detector (plate of CR-39). open cup. filtered cup came out to be (37.36±0.6)×10^-4, (25.3±0.8)×10^-4, and (16.6±0.5)×10^-4trㆍm^-3ㆍd). respectively, Detection of radon in air by means of installed radon cups at various height up to 1m above ground of open field in CNUI)aedeok campus has been carried out for five months from June to October, 1989, on the monthly basis. The mean value of radon concentration measured and assessed are turned out to be (55.6±16.5)×10^-4Bqㆍm^-3 and (50.5±26.6)×10^-4Bqㆍm^-3 in the case of open and filtered cup detections, respectively.

십이지장 궤양 환자와 만성 위염 환자의 염증 분포의 차이 및 H. pylori 집락도와 염증도의 상관관계

유광하,진춘조,박형석,이재동,김예리,윤성욱,이수인,윤호상 건국대학교 의과학연구소 1998 건국의과학학술지 Vol.8 No.-

An inflammatory difference between the gastric antrum, body and fundus was studied in 39 H.pylroi positive duodenal ulcer and 29 H. pylori chronic gastritis patients. Also we studied correlation of H. pylori colony count and inflammatory severity. Patients with newly diagnosed duodenal ulcer and chronic gastritis were endoscoped and two biopsy secimens each taken from the antrum, body and fundus. Although intestinal metaplasia in antrum and inflammatory activity in fundus were more severe in chronic gastritis patients. another inflammatory difference was equally likely to be found between two groups. There was no definite histological inflammatory difference between duodenal ulcer and chronic gastritis patients. A positive correlation was found between the number of H. pylori and the severity of inflammation.

회맹장 판막에 발생한 아니사키스증 1례

이재익,박정하,김준영,조영완,진한영,강명주,정은욱,박석주,양성연 인제대학교 2006 仁濟醫學 Vol.27 No.-

Anisakiasis refers to parasitic infestation by nematode larvae that belongs to the subfamily Anisakinae, and this condition is seen in people who eat inadequately prepared or raw salt-water fish. While gastric anisakiasis is commonly diagnosed by endoscopic technique, intestinal anisakiasis is rare because it is less common and the clinical and radiologic features are poorly understood. The authors report a case of human anisakiasis involving the ileocecal valve in 62-year-old man who had the history of eating raw cuttlefish.