• The Korean Journal of Pain
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• 제35권2호
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• pp.129-139
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• 2022

C-arm fluoroscopy is a useful tool for interventional pain management. However, with the increasing use of C-arm fluoroscopy, the risk of accumulated radiation exposure is a significant concern for pain physicians. Therefore, efforts are needed to reduce radiation exposure. There are three types of radiation exposure sources: (1) the primary X-ray beam, (2) scattered radiation, and (3) leakage from the X-ray tube. The major radiation exposure risk for most medical staff members is scattered radiation, the amount of which is affected by many factors. Pain physicians can reduce their radiation exposure by use of several effective methods, which utilize the following main principles: reducing the exposure time, increasing the distance from the radiation source, and radiation shielding. Some methods reduce not only the pain physician's but also the patient's radiation exposure. Taking images with collimation and minimal use of magnification are ways to reduce the intensity of the primary X-ray beam and the amount of scattered radiation. It is also important to carefully select the C-arm fluoroscopy mode, such as pulsed mode or low-dose mode, for ensuring the physician's and patient's radiation safety. Pain physicians should practice these principles and also be aware of the annual permissible radiation dose as well as checking their radiation exposure. This article aimed to review the literature on radiation safety in relation to C-arm fluoroscopy and provide recommendations to pain physicians during C-arm fluoroscopy-guided interventional pain management.

• 방사선산업학회지
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• 제7권2_3호
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• pp.221-224
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• 2013

RI-Biomics is a new compound word of radiation technology and Biomics related to the study of life. RI-Biomics is high radiation fusion technology by combining evaluation of pharmacokinetics in vivo (RI-ADME) of new drugs and medical materials using radioisotope and molecular imaging technology using nuclear medicine equipments. RI-Biomics fields are emerging with the increasing usage of radioisotopes (RI). In this paper, we investigated the latest trends of radioisotope using in RI-Biomics fields. The representative radioisotopes are $^{14}C$, $^3H$ and $^{32}P$ for the optimization and the selection of candidates in the development process of new drugs among the RI-Biomics fields. As shown in the status of accumulated income of radioisotopes, using amounts of radioisotopes are showing a tendency to increase every year. $^{14}C$ is 61.6% increase of accumulated income growth rate and $^3H$ increased by 58.8% and $^{32}P$ increased by 33.9% in 2012 compared to 2007. These isotopes are used in a variety of fields as using of $^{14}C$ for microdosing test, development of [$^3H$]cholesterol absorption inhibitors, study of [$^{131}I$]pyronaridine tetraphosphate for malaria therapy. These are going on in vivo test sucessfully. So, clinical research step is expected to begin soon. Therefore, usages of radioisotopes are necessary and need for the evaluation of pharmacokinetics, optimization and the selection of new drug candidates in the development process of new drugs among the RI-Biomics fields. So, using of radioisotopes is predict to increase continuously except for primarily used $^{14}C$, $^3H$.

• 방사선산업학회지
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• 제4권1호
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• pp.47-51
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• 2010

Centipedegrass is a warm season turfgrass in the world. Chlorogenic acid (CA) is one of the important compounds present in the leaf of centipedegrass and already known as an antioxidant, CA has become a key resistance against insect pests and bacteria pathogens of agricultural and horticultural plants during seedling stage. Furthermore, CA is accumulated by abiotic stress such as an UV irradiation. In present study, we investigated enhancement of the level of CA upon gamma irradiation in centipedegrass. The high performance liquid chromatography (HPLC) data analysis showed an approximately increasing of the CA levels from among the irradiated samples. However, plants irradiated at 50 Gy showed a constant increase in the CA level (0.0066 to $0.114mg\;ml^{-1}$ and 0.0258 to $0.2211mg\;ml^{-1}$, respectively) from $3^{rd}$ to $15^{th}$ day among one and three month irradiated plants compared to control. The present study, indicates an increase in the CA level upon gamma irradiation, suggests strategy for conferment of strong resistance in seedling stage plants by gamma irradiation as simplicity and cheaply method.

• 한국작물학회지
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• 제26권1호
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• pp.90-95
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• 1981

참깨 재배지역 차이에 따른 품종문제를 추적하여 본 결과 다음과 같은 결론을 얻였다. 1. 참깨 재배지역에 따른 품질은 남부지역에서 생산된 것보다 중북부지역에서 생산된 것이 리놀산함량이 많았다. 2. 러놀산함량은 등열기간 중 적산온도와 r =-0.595**의 부상관관계를 일사량과는 r=0.613**의 정상관을 보여서 등열기간의 적산온도가 낮고 일사양이 많으며 강우량도 많은 조건에서 리놀산함량 높았다. 3. 오레인산함량에서는 리놀산의 경우와 달리 남부지방에서 생산된 참깨가 중북부산 참깨보다 오레인산함량이 더 높았다. 4. 오레인산함량은 등숙기간 중 적정평균 온도와 r=0.644**의 정상관관계를 일사량과는 r=-0.456**의 부상관 관계를 보였다. 5. 참깨 지방산중 오레인산과 리놀산함량은 이두 지방산함량이 대부분 차지하고 있음으로 서로 상대적인 함량관계를 가지고 있는 경향이다. 6. 참깨의 유질은 주산지인 남부보다 중북부산 참깨의 품질이 더 우수하다.

• 한국자기공명학회논문지
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• 제6권2호
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• pp.84-88
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• 2002

Dating and dosimetry using electron spin resonance (ESR) in 20th Century developed at both Yamaguchi University and Osaka University have been reviewed with emphasis on new prospects and strategies in 21th century. Natural radiation have been generating radicals that accumulated in archaeological and geological materials. ESR detects these radicals and the ESR signal intensity is proportional to the radiation dose and therefore the age. The assessment of the total dose of natural radiation and the annual dose rate give their ESR ages. The ESR dating of stalactites and stalagmites ant Akiyoshi cave in Yamaguchi prefecture in 1975 was extended to anthropological dating using bones and tooth enamel excavated in Greek Petralona cave. Fossils of shells and corals gave the ages of marine terraces and sea-level changes. Quartz grains gave the ages of geothermal alteration and fault movements. Future ESR dating of ices at outer planets anf their satellite are also investigated as basic studies for ices od $H_2O,\;CO_2,\;SO_2$ as well as terrestrial hydrates in laboratory. Atomic bomb radiation dosimetry at Hiroshima and Nagasaki using ESR lead to the dosimetry of personnel, Chemobyl and JCO criticality accidents. Monitoring of radiation dose with sensitive materials with tissue equivalence are being developed. finally a new scanning ESR imaging apparatus (a near field microwave microscope) developed in our laboratory gave ESR images of Radicals from fossils to Si-CVD and diamond films as summarized in my book in 2002.

• Korean Journal of Radiology
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• 제23권5호
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• pp.517-528
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• 2022

Due to its excellent diagnostic performance, CT is the mainstay of diagnostic test in adults with suspected acute appendicitis in many countries. Although debatable, extensive epidemiological studies have suggested that CT radiation is carcinogenic, at least in children and adolescents. Setting aside the debate over the carcinogenic risk of CT radiation, the value of judicious use of CT radiation cannot be overstated for the diagnosis of appendicitis, considering that appendicitis is a very common disease, and that the vast majority of patients with suspected acute appendicitis are adolescents and young adults with average life expectancies. Given the accumulated evidence justifying the use of low-dose CT (LDCT) of only 2 mSv, there is no reasonable basis to insist on using radiation dose of multi-purpose abdominal CT for the diagnosis of appendicitis, particularly in adolescents and young adults. Published data strongly suggest that LDCT is comparable to conventional dose CT in terms of clinical outcomes and diagnostic performance. In this narrative review, we will discuss such evidence for reducing CT radiation in adolescents and young adults with suspected appendicitis.

• 한국작물학회지
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• 제35권2호
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• pp.151-155
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• 1990

콩군락에 흡수된 단파폭사와 건물생산과의 관계를 단경밀식적응품종인 팔달콩을 공시하여 조사한 결과를 요약하면 다음과 같다. 1. 단파폭사의 군락에서의 감쇄계수는 0.53, 총투과된 양은 입사된 단파폭사량의 31.9%이었다. 2. 생육시기별 지하부 건물중과 그 기간에 군락이 흡수한 단파폭사의 적산치는 등숙기인 출현후 88일항까지는 직선적 비례관계가 성립하였고, 건물로의 변환효율인 비례계수는 1.45gMJ$^{-1}$이었다. 3. 생육기간의 전체반사율은 24.7%이었으며 엽면적지수(LAI) 2.5 이상에서는 입사량에서 투과량을 뺀값과 반사폭사량간의 상관도가 높았다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권1호
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• pp.319-323
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• 2012

Objective: To explore the feasibility of shrinking field technique after 40 Gy radiation through 18F-FDG PET/CT during treatment for patients with stage III non-small cell lung cancer (NSCLC). Methods: In 66 consecutive patients with local-advanced NSCLC, 18F-FDG PET/CT scanning was performed prior to treatment and repeated after 40 Gy. Conventionally fractionated IMRT or CRT plans to a median total dose of 66Gy (range, 60-78Gy) were generated. The target volumes were delineated in composite images of CT and PET. Plan 1 was designed for 40 Gy to the initial planning target volume (PTV) with a subsequent 20-28 Gy-boost to the shrunken PTV. Plan 2 was delivering the same dose to the initial PTV without shrinking field. Accumulated doses of normal tissues were calculated using deformable image registration during the treatment course. Results: The median GTV and PTV reduction were 35% and 30% after 40 Gy treatment. Target volume reduction was correlated with chemotherapy and sex. In plan 2, delivering the same dose to the initial PTV could have only been achieved in 10 (15.2%) patients. Significant differences (p<0.05) were observed regarding doses to the lung, spinal cord, esophagus and heart. Conclusions: Radiotherapy adaptive to tumor shrinkage determined by repeated 18F-FDG PET/CT after 40 Gy during treatment course might be feasible to spare more normal tissues, and has the potential to allow dose escalation and increased local control.

• 한국태양에너지학회 논문집
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• 제32권2호
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• pp.64-73
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• 2012

The angle of solar panels is calculated using solar radiation model for the efficient solar power generation. In ideal state, the time of maximum solar radiation is represented from 12:08 to 12:40 during a year at Gangneung and it save rage time is12:23. The maximum solar radiation is 1012$W/m^2$ and 708$W/m^2$ inc lear sky and cloudy sky, respectively. Solar radiation is more sensitive to North-South (N-S) slope angle than East-West (E-W) azimuth angle. Daily solar radiation on optimum angle of solar panel is higher than that on horizontal surface except for 90 days during summer. In order to apply to the real atmosphere, the TMY (typical meteorological Year) data which obtained from the 22 solar sites operated by KMA(Korea Meteorological Administration) during 11 years(2000 to 2010) is used as the input data of solar radiation model. The distribution of calculated solar radiation is similar to the observation, except in Andong, where it is overestimated, and in Mokpo and Heuksando, where it is underestimated. Statistical analysis is performed on calculated and observed monthly solar radiation on horizontal surface, and the calculation is overestimated from the observation. Correlationis 0.95 and RMSE (Root Mean Square Error) is10.81 MJ. The result shows that optimum N-S slope angles of solar panel are about $2^{\circ}$ lower than station latitude, but E-W slope angles are lower than ${\pm}1^{\circ}$. There are three types of solar panels: horizontal, fixed with optimum slope angle, and panels with tracker system. The energy efficiencies are on average 20% higher on fixed solar panel and 60% higher on tracker solar panel than compared to the horizontal solar panel, respectively.

• 항공우주기술
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• 제10권1호
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• pp.193-200
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• 2011

본 연구는 저궤도의 태양동기궤도 위성에 미치는 외란 토크의 크기와 영향을 해석하였다. 위성체 좌표계에서 보았을 때, 지구 지향 자세에서 최대 토크는 약 $8.3{\times}10^{-4}$ Nm로 한 궤도당 약 1.4 Nms 의 모멘텀이 축적되고, 태양지향 자세에서의 최대 토크는 약 $1.6{\times}10^{-3}$ Nm로 한 궤도당 약 3.0 Nms 의 모멘텀이 축적된다. 한 궤도당 축적되는 모멘텀의 양은 토커의 크기를 결정하는 설계 기준 자료로 사용되는데, 현재 사용 가능한 자기 토커의 한 궤도당 모멘텀 덤핑 용량을 고려했을 때, 위성의 임무 수행을 위해 적절한 선택임을 확인하였다.