• 제목/요약/키워드: External exposure

검색결과 339건 처리시간 0.026초

방사선피폭관리시스템를 위한 D-Shuttle 선량계의 방사선 선량측정 (Radiation Dose Measurement of D-Shuttle Dosimeter for Radiation Exposure Management System)

  • 권대철
    • 한국방사선학회논문지
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    • 제11권5호
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    • pp.321-328
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    • 2017
  • D-Shuttle (Chiyoda Technol Corporation, Tokyo, Japan) 선량계를 이용하여 개인피폭관리 및 자연방사선량의 모니터링을 위한 기초자료를 제공하는데 연구의 목적이 있다. D-Shuttle을 이용하여 선량을 산출하였다. 선량보고서에서 400 일 노출되었을 때에 1.346 mSv 이었고, 연간선량 (annual dose per year)은 1.228 mSv/year, 평균시간선량 (average dose per hour)은 $0.014{\mu}Sv/hr$ 이었다. 국내의 개인 외부피폭선량 (1.295 mSv/year =Korea average natural individual external dose), 국내의 연간부가선량 (additional dose per year)은 -0.0663 mSv/year 이다. D-Shuttle은 방사선모니터링을 위한 개인선량계로 방사선의 검출성능 우수한 기능, 실시간 방사선 피폭관리, 방사선 작업의 경보 기능, 효율적이고 사용이 편리한 개인 방사선선량의 피폭관리로 ALARA에 매우 유용한 선량계로 사용할 수 있다. 방사선작업종사자와 지역주민의 방사선모니터링 측정기기로 병원, 산업, 의료현장, 원전사고 지역과 비파괴 분야의 위험한 지역에서 방사선모니터링으로 활용될 수 있다.

The External Auricular Reconstruction with Inferior Based Retroauricular Flap Including the Posterior Auricular Artery

  • Choi, Jong Hwan;Ki, Sae Hwi
    • Archives of Reconstructive Microsurgery
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    • 제25권1호
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    • pp.1-6
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    • 2016
  • Purpose: The external ear is a common area of trauma on the body prone to exposure of ultraviolet light, which can lead to skin cancer. Thus, variable techniques have been developed and used for reconstruction of the external ear. The aim of this study is to review the surgical method, its area of application, as well as advantages and pitfalls of reconstruction of the external ear with inferior based retroauricular flaps. Materials and Methods: Eight patients underwent external ear reconstruction with inferior based retroauricular flap for external ear defects in our institute from September 2012 to June 2015. According to the area of the defect, patients were classified as middle 1/3 (n=4), inferior 1/3 (n=2), superior auroculo-cephalic sulcus (n=1), and external auditory canal (n=1). Results: All of the flaps survived the operation and there was no marginal necrosis. Mean size of the defect was $2.8{\times}1.8cm$ and mean size of the retroauricular flap was $5{\times}2cm$. For insetting of the flap, a subcutaneous tunneling technique was used in 6 cases and rotation without subcutaneous tunneling was used in 2 cases. Transient paresthesia occurred in 3 cases. Two cases recovered within 3 months but one case did not recover until 6 months. Conclusion: The inferior based retroauricular flap is an available technique in external ear reconstruction with one stage operation.

Region-wise evaluation of gamma-ray exposure dose in decontamination operation after a nuclear accident

  • Jeong, Hae Sun;Hwang, Won Tae;Han, Moon Hee;Kim, Eun Han;Lee, Jo Eun;Lee, Cheol Woo
    • 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.

복식에 표현된 노출 (Exposure Expressed in Dress)

  • 정연자
    • 한국의상디자인학회지
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    • 제1권1호
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    • pp.91-107
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    • 1999
  • The primary purpose of this study is to inquire into the characteristic of exposure presented in fashion, identify the correct concept of exposure from an aesthetic perspective, and grasp the contemporary meaning of exposure presented in fashion. As a result of study, the following findings were obtained: First, the surrealist style of fashion exhibited representations such as the relocation of the partial details, the harmonization of the natural and the artificial, the emphasis or expansion of each part of the body, and the like. It used highlighted the genital region with ornamentations or used the technique of paradoxically exposing the part of the body always covered. And it exbibited the paradoxical relationship of exposure and concealment by exposing the concealed part of the human body. Second, the post-modern style showed the complicated phenomenon that the values of several meanings such as the historic, the folk, and the like appeared in its fashion. It shares in spatiotemporal eclecticism, pluralistic characteristics and the like found in the post-modern culture. Third, the deconstructive style gets rid of the distinction between the external space and the private space by translating underwears into outer garments. It destroys clothing by tearing or perforating clothing whereby it represents the poor image. Coupled with women‘s psychology of exposure and the new generation’s way of thinking indifferent to others‘ eyes, this fashion of deconstruction occupies the great current of fashion. Deconstructive fashion gets away with the rule of ‘having to wear clothing to suit TPO(Time, Place and Occasion), the traditional norm of wearing clothing.

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표준한국인(標準韓國人)의 최대허용(最大許容) 피폭선량(被曝線量) 설정(設定)에 관한 연구(硏究) - 체위(體位) 및 내(內).외부(外部) 피폭선량(被曝線量) 추정(推定) - (Studies on the Reference Korean and Estimation of Radiation Exposure Dose - PHYSICAL STANDARD AND ESTIMATION OF INTER-EXTERNAL RADIATION EXPOSURE DOSE -)

  • Kim, Yung-J.;Lee, Kang-S.;Chun, Ki-J.;Kim, Jong-B.;Chung, Gook-H.;Kim, Sam-R.
    • Journal of Radiation Protection and Research
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    • 제7권1호
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    • pp.1-10
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    • 1982
  • 표준한국인(標準韓國人)의 체위(體位)와 내(內).외부(外部) 피폭선량(被曝線量)을 추정(推定)하기 위하여 한국인(韓國人)의 신장(身長), 체중(體重), 체표면적(體表面積)을 포함(包含)한 체위(體位)와 음식물섭취량(飮食物攝取量) 방사능물질섭취량(放射能物質攝取量) 그리고 환경방사능(環境放射能)에 의한 피폭선량(被曝線量)을 조사분석(調査分析)하여 다음과 같은 결론(結論)을 얻었다. 1) 표준한국인(標準韓國人)의 년령군(年齡群)은 남녀(男女) 모두 $20{\sim}30$세(歲)이며 남자(男子)에 있어서의 신장(身長)은 167cm, 체중(體重)은 61kg, 체표면적(體表面積)은 $1.67m^2$다. 그리고 여자(女子)에 있어서의 신장(身長)은 155cm, 체중(體重)은 51kg, 체표면적(體表面積)은 $1.51m^2$이다. 2) 한국인(韓國人) 성인(成人)은 1인(人) 1일(日) 812.8g(식물성((植物性) 669.6g, 동물성(動物性) 143.2g)의 음식물(飮食物)을 섭취(攝取)한다. 3) 한국인(韓國人) 성인(成人)은 음식물(飮食物)을 통(通)하여 1인(人) 1일(日) 약(約) 1,200pCi(${\beta}$-선(線))의 방사능물질(放射能物質)을 섭취(攝取)한다. 4) 한국인(韓國人) 성인(成人)은 년간(年間) 127mrem의 외부피폭(外部被曝)과, 8mrem의 내부피폭(內部被曝)으로 약(約) 135mrem의 환경방방선(環境放放線)에 피폭(被曝)되는 것으로 추산(推算)되나 이 선량치(線量値)는 앞으로 더 많은 자료(資料)가 보완(補完)됨에 따라 수정(修正)된다고 본다.

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국내·외 방사성폐기물 해상운반 현황 및 침몰사고 시 일반인 선량평가 사례 분석 (Analysis of Domestic and Overseas Radioactive Waste Maritime Transportation and Dose Assessment for the Public by Sinking Accident)

  • 오가은;곽민우;김혁재;김광표
    • 방사선산업학회지
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    • 제18권1호
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    • pp.35-42
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    • 2024
  • Demand for RW transportation is expected to increase due to the continuous generation of RW from nuclear power plants and facilities, decommissioning of plants, and saturation of spent fuel temporary storage facilities. The locational aspect of plants and radiation protection optimization for the public have led to an increasing demand for maritime transportation, necessitating to apprehend the overseas and domestic current status. Given the potential long-term radiological impact on the public in the event of a sinking accident, a pre-transportation exposure assessment is necessary. The objective of this study is to investigate the overseas and domestic RW maritime transportation current status and overseas dose assessment cases for the public in sinking accident. Selected countries, including Japan, UK, Sweden, and Korea, were examined for transport cases, Japan and the U.S were chosen for dose assessment case in sinking accidents. As a result of the maritime transportation case analysis, it was performed between nuclear power plants and reprocessing facilities, from plants to disposal or intermediate storage facilities. HLW and MOX fuel were transported using INF 3 shipments, and all transports were performed low speed of 13 kn or less. As a result of the dose assessment for the public in sinking accident, japan conducted an assessment for the sinking of spent fuel and vitrified HLW, and the U.S conducted for the sinking of spent fuel. Both countries considered external exposure through swimming and working at seashore, and internal exposure through seafood ingestion as exposure pathway. Additionally, Japan considered external exposure through working on board and fishing, and the U.S considered internal exposure through spray inhalation and desalinized water and salt ingestion. Internal exposure through seafood ingestion had the largest dose contribution. The average public exposure dose was 20 years after the sinking, 0.04 mSv yr-1 for spent fuel and 5 years after the sinking, 0.03 mSv yr-1 for vitrified HLW in Japan. In the U.S, it was 1.81 mSv yr-1 5 years after the sinking of spent fuel. The results of this study will be used as fundamental data for maritime transportation of domestic RW in the future.

18-FDG EXTERNAL RADIATION DOSE RATES IN DIFFERENT BODY REGIONS OF PET-MRI PATIENTS

  • Han, Eunok;Kim, Ssangtae
    • Journal of Radiation Protection and Research
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    • 제38권3호
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    • pp.157-165
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    • 2013
  • To determine the factors affecting the external radiation dose rates of patients undergoing PET-MRI examinations and to assess the trends of these differences, we measured the changes in the dose rates of $^{18}F$-FDG during a set period of time for each body region. Consistent with theoretical predictions, the dose rate decreased over time in patients undergoing PET-MRI examinations. Furthermore, immediately after the $^{18}F$-FDG injection, the dose rate in the chest region was the highest, followed by the abdominal region, the head region, and the foot region. The dose rate decreased drastically as time passed, by 2.47-fold, from $339.23{\pm}74.70mSv\;h^{-1}$ ($6.73{\pm}5.79$ min) at the time point immediately after the $^{18}F$-FDG injection to $102.71{\pm}26.17mSv\;h^{-1}$ ($136.11{\pm}25.64$ min) after the examination. In the foot region, there were no significant changes over time, from $32.05{\pm}20.23mSv\;h^{-1}$ ($6.73{\pm}5.79$ min) at the time point immediately after the $^{18}F$-FDG injection, to $23.89{\pm}9.14mSv\;h^{-1}$ ($136.11{\pm}25.64$ min) after the examination. The dose rate is dependent on the individual characteristics of the patient, and differed depending on the body region and time point. However, the dose rates were higher in patients who had a lower body weight, shorter stature, fewer urinations, lower fluid intake, and history of diabetes mellitus. To decrease radiation exposure, it is difficult or impossible to change factors inherent to the patient, such as sex, age, height, body weight, obesity, and history of diabetes mellitus. However, factors which can be changed, such as the $^{18}F$-FDG dose, fasting time, fluid intake, number of urinations, and contrast agent dose can be controlled to minimize the external radiation exposure of the patient.

Validation of a Model for Estimating Individual External Dose Based on Ambient Dose Equivalent and Life Patterns

  • Sato, Rina;Yoshimura, Kazuya;Sanada, Yukihisa;Sato, Tetsuro
    • Journal of Radiation Protection and Research
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    • 제47권2호
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    • pp.77-85
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    • 2022
  • Background: After the Fukushima Daiichi Nuclear Power Station (FDNPS) accident, a model was developed to estimate the external exposure doses for residents who were expected to return to their homes after evacuation orders were lifted. However, the model's accuracy and uncertainties in parameters used to estimate external doses have not been evaluated. Materials and Methods: The model estimates effective doses based on the integrated ambient dose equivalent (H*(10)) and life patterns, considering a dose reduction factor to estimate the indoor H*(10) and a conversion factor from H*(10) to the effective dose. Because personal dose equivalent (Hp(10)) has been reported to agree well with the effective dose after the FDNPS accident, this study validates the model's accuracy by comparing the estimated effective doses with Hp(10). The Hp(10) and life pattern data were collected for 36 adult participants who lived or worked near the FDNPS in 2019. Results and Discussion: The estimated effective doses correlated significantly with Hp(10); however, the estimated effective doses were lower than Hp(10) for indoor sites. A comparison with the measured indoor H*(10) showed that the estimated indoor H*(10) was not underestimated. However, the Hp(10) to H*(10) ratio indoors, which corresponds to the practical conversion factor from H*(10) to the effective dose, was significantly larger than the same ratio outdoors, meaning that the conversion factor of 0.6 is not appropriate for indoors due to the changes in irradiation geometry and gamma spectra. This could have led to a lower effective dose than Hp(10). Conclusion: The estimated effective doses correlated significantly with Hp(10), demonstrating the model's applicability for effective dose estimation. However, the lower value of the effective dose indoors could be because the conversion factor did not reflect the actual environment.

ZnO 박막 전자수송층의 공기 노출에 의한 양자점 발광다이오드의 특성 변화 (Effect of Air Exposure on ZnO Thin Film for Electron Transport Layer of Quantum Dot Light-Emitting Diode )

  • 서은용;이경재;황정하;김동현;임재훈;이동구
    • 센서학회지
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    • 제32권6호
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    • pp.455-461
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    • 2023
  • We investigated the electrical characteristics of ZnO nanoparticles (NPs) with air exposure that is a widely used electron transport layer for quantum dot light-emitting diodes (QLEDs). Upon air exposure, we observed changes in the density of states (DOS) of the trap levels of ZnO NPs. In particular, with air exposure, the concentration of deep trap energy levels in ZnO NPs decreased and electron mobility significantly improved. Consequently, the air-exposed ZnO reduced leakage current by approximately one order of magnitude and enhanced the external quantum efficiency at the low driving voltage region of the QLED. In addition, based on the excellent conductivity properties, high-brightness QLEDs could be achieved.

African-American Hair Damage Study

  • Tang, Diana
    • 대한화장품학회:학술대회논문집
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    • 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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    • pp.413-416
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    • 2003
  • Hair fragility is a major concern to most people of African decent due to frequent chemical treatments, thermal appliance use and environmental exposure. It is extremely important to both cosmetic scientists and African-American consumers to understand the internal and external hair damage caused by these factors.(omitted)

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