• Radiation Oncology Journal
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• 제10권1호
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• pp.15-20
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• 1992

1980년부터 1990년까지 연세의료원 암쎈터 치료방사선과에서 방사선 치료를 받은 20예 (남자 : 여자=10:10, 성인 소아=8:12)의 뇌간종양 환자의 치료결과를 분석하여 보았다. 총 20예의 환자 중 13예에서는 보통 분할 방사선치료(분할 당 180%200 cGy, 주 5회, 총 4680\~5400 cGy)를 시행하였고 나머지 7예에서는 과분할 방사선치료(분할 당 100 cGy, 1일 2회, 주 10회 총 7200 cGy)를 시행하였다. 중앙 추적 기간은 보통 분할 방사선 치료군과 과분할 방사선 치료군에서 각각 36개월과 10개월이었다. 20예의 환자중 4예에서는 치료전 병리학적 진단을 얻을 수 있었다. 이중 3예는 저분화 성상 세포종양 이었고 1예는 미분화 성상 세포종양이었다. 전체 대상환자의 실제 2년 생존율은 30%이었다. 예후인자로 나이, 증상 발현기간, 종양 형태 등을 분석해 보았는데, 증상 발현기간이 긴 환자에서 짧은 환자보다 예후가 좋았고, 성인에서 소아보다 예후가 좋았다. 종양 형태간에는 차이가 없었다. 보통 분할 방사선 치료군보다 과분할 방사선 치료군에서 초기 임상적 치료 반응이 좋았다. 보통 분할 방사선 치료군과 과분할 방사선치료군을 비교하는 것은 환자의 숫자가 적고, 과분할 방사선치료군의 추적 기간이 짧아 어려웠다.

• 전기학회논문지
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• 제56권12호
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• pp.2122-2126
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• 2007

A special PM-Tube(Photo Multiplier Tube) that is using the photoelectric effect has been designed and manufactured to measure the radiation energy of arc in a gas circuit breaker(GCB). The PM-Tube, LLG(liquid light guides), ND(neutral density) filter, and a model gas circuit breaker have been combined for the reception and the transmission of the light and a simplified synthetic test facility with the arc energy measuring system has been established. In the case of $SF_6$ gas pressure $5kg.f/cm^2$ and arc length 20mm, the radiation energy increases with the arc current but it tend to be saturated in the above 20kA. Under the arc current 20kA, the total radiation energy has the biggest value around 8kA and was not exceeded 40% of the total arc energy.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 추계학술발표회논문집(2)
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• pp.629-635
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• 1996

The lifetime radiation-induced cancer mortality for Korean has been estimated for both single and continuous radiation exposure using the BEIR V method. In case of single exposure, a dominant cancer site for young and old ages was digestive and respiratory cancer, respectively. For Korean population, digestive cancer was the most dominant radiation-induced cancer site. In case of 1 mGy/yr continuous exposure from birth to death, the contribution of total radiation-induced cancer mortality was negligible as within 3% in comparison with total natural cancer mortality.

• 보존과학회지
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• 제36권4호
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• pp.236-243
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• 2020

In this study, an accelerated aging experiment for fabric and paper was conducted using two light emitting diode(LED) sources with different wavelength characteristics, and the discoloration under each lighting type was examined. Hanji(Korean traditional paper) and related textiles showed more discoloration under blue LEDs, while the blue wool standard showed more discoloration under white LEDs. This, indicated that the deterioration varied depending on the sample color. The the effect of the light source on artifact deterioration was primarily related to the total radiation flux(expressed in mill watts), rather than the total luminous flux(expressed in lumens). In addition, the discoloration of the investigated artifacts was dependent on the color rendering of the lighting.

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2663-2665
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• 2013

Objective: To compare the efficacy and complications of chemotherapy and late course three-dimensional conformal radiotherapy (3DCRT) in treating patients with stage III non-small cell lung cancer (NSCLC). Patients and Methods: All patients were divided into two groups: to receive chemotherapy and late course 3DCRT (3DCRT group), or chemotherapy and conventional fraction radiation (control group). In the 3DCRT-group, patients were given 6~15 MV X-rays with a total dose of 40 Gy, followed by 3DCRT, 2.5 Gy~3.0 Gy per fraction, 1 fraction/every day, total 68 Gy~70 Gy; in the control group, with conventional fraction radiation the total dose was 64~66 Gy. The chemotherapy regimen in both cases was EP (VP-16 and DDP). Results: Sixty four patients with stage III NSCLC were divided into two groups: 32 patients into 3DCRT, 32 into the control group. One and 2-year survival rates in 3DCRT and control group were 87.5%, 56.3%mad 65.6%, 34.4%, respectively (P<0.05); local control rates were 90.6%, 81.3% and 65.6%, 53.1%, respectively (P<0.05). Conclusion: Chemotherapy and late course 3DCRT is associated with improved survival rate in patients with stage III NSCLC with good tolerability.

• Radiation Oncology Journal
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• 제7권2호
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• pp.227-233
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• 1989

From April 1986 to Dec 1988, fifty one patients with carcinoma of lung were treated by radiation therapy in Department of Therapeutic Radiology, Yeungnam University Hospital Of the 51 patients, $31(61\%)$ were squamous cell ca, $8(15.7\%)$ were small cell ca, and remained $4(7.9\%)$ were other cell types. Total radiation dose was average $64Gy (60\~75 Gy)$ for group A and 45Gy $(40\~59Gy)$ for group B. The mass regression and the response of airway obstruction to radiation therapy was established on the basis of follow up chest X-ray. The mass regression above $50\%$ of total volume was noted in 23 patients $(74.2\%)$ among 31 patients and the difference between two groups was not seen. In squamous cell ca, however, the mass regression rate (above $50\%$ of total volume) was $83.3\%$ (10/12) in group A compared to $50\%$ (3/6) in group B(p<0.05). The alleviation of airway obstruction was noted as follows. In group A, CR $42.9\%$, PR $35.7\%$, no response $21.4\%$ and in group B, CR $55.6\%,\;PR\;33.3\%$, no response $11.1\%$. But, in squamous cell ca, responsiveness is higher than group B. The study indicates that the importance of higher radiation dose in the management of primary tumor mass and airway obstruction caused by lung cancer especially squamous cell ca. So, meticulous treatment planning and multimodality combination therapy without increasing si.do elect or complication is recommended in management of inoperable bronchogenic carcinoma.

• Nuclear Engineering and Technology
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• 제36권1호
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• pp.1-11
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• 2004

Two approximate methods for a cosmic radiation shielding calculation in low earth orbits were developed and assessed. Those are a sectoring method and a chord-length distribution method. In order to simulate a change in cosmic radiation environments along the satellite mission trajectory, IGRF model and AP(E)-8 model were used. When the approximate methods were applied, the geometrical model of satellite structure was approximated as one-dimensional slabs, and a pre-calculated dose-depth conversion function was introduced to simplify the dose calculation process. Verification was performed with mission data of KITSAT-1 and the calculated results were also compared with detailed 3-dimensional calculation results using Monte Carlo calculation. Dose results from the approximate methods were conservatively higher than Monte Carlo results, but were lower than experimental data in total dose rate. Differences between calculation and experimental data seem to come from the AP-8 model, for which it is reported that fluxes of proton are underestimated. We confirmed that the developed approximate method can be applied to commercial satellite shielding calculations. It is also found that commercial products of semi-conductors can be damaged due to total ionizing dose under LEO radiation environment. An intensive shielding analysis should be taken into account when commercial devices are used.

• 대한방사선치료학회지
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• 제9권1호
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• pp.87-93
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• 1997

The using of compensator is required to adjust the irregular dose distribution due to irregular thickness of the body in Total Body Irradiation. Aluminuim, copper or lead is generally used as compensator. In our study, we would like to introduce a result of the attenuation and compensation effect of radiation use compensator made by duralumin and its clinical use. The thickness of compensator was calculated by the attenustion of radiation, which was measured by polystyrene phantom and ionization chamber(farmer). The compensation effect of radiation was measured by diode detector. All of conditions were set as in real treatment, and the distanc from source to detector was 446 cm. We also made fixation of device to easily attach the compensator to LINAC. Beam spoiler was menufactured and placed on the patient to irradiate sufficient dose to the skin. diode detector were placed on head, neck, chest, umbilicus. pelvis and knee with each their entranced exit points, and datas of dose distribution were evaluated and compared in each points for eleven patients(Feb. 96-Feb. 97). The attenuation rate of irradiation by duralumin compensator was measured as $1.4\%$ in 2mm thickness. The mean attenuation rate was $1.3\%$ per 2mm as increasing the thickness gradually to 50 mm. By using duralunim compensator, dose distribution in each points of body was measured with ${\pm}2.8\%$ by diode detectior. We could easily calculate the thickness of compensator by measuring the attenuation rate of radiation, remarkably reduce the irragularity of dose distribution duo to the thickness of body and magnify the effect of radiation therapy.

• 한국환경농학회지
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• 제24권1호
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• pp.66-70
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• 2005

The experiment was carried out to investigate the effects of gamma radiation on the early growth performance and physiological traits of BT2 clone tea, the most promising cultivar released by Bangladesh Tea Research Institute. The fresh shoot cuttings were irradiated with seven different levels of gamma radiation such as 0, 10, 20, 30, 40, 50 and 60 Gy from Cobalt 60Co source (Dept. of PlantBreeding, Bangladesh Institute of Nuclear Agriculture). Thereafter, the irradiated shoot cuttings were planted in polythene bags and kept under natural conditions. It was observed that callusing was initiated from 8th weeks after placement of tea shoot cuttings in the polythene bags and completed by 12th weeks. The morphological growth of tea shoot cuttings were recorded under varying levels of gamma radiation and growth stages. It was observed that the number of leaves, number of primary branches, base diameter, root length and total leaf area per plant significantly increased with the progress of time and increasing levels of gamma radiation, however, the plant height showed decreasing trend with the increasing levels of gamma radiation, which could be due to the change in chromosomal structure and genetic makeup. After 56 weeks of planting, the plant height, the number of leaves and primary branches per plant, base diameter, root length and total leaf area per plant recorded were 65.70 cm, 30.67, 7.33, 1.48 cm, 23.50 cm, and 1250.67 cm2 per plant respectively under the radiation level 60 Gy, whereas the corresponding figures of the above parameters at the control treatment were 76.21 cm, 18.33, 3.67, 0.92 cm, 17.75 cm and 778.33 cm2 per plant, respectively. A significant relationship was observed among the physiological growth parameters with the increasing levels of gamma radiation. The total dry matter gain, leaf area index, absolute growth rate and relative growth rate were significantly influenced with the rising levels of gamma radiation (up to 60 Gy), whereas the net assimilation rate of individual tea plant non-significantly responded as compared to those of control treatment. Finally after 56 weeks of planting, the maximum total dry weight gain, leaf area index, absolute growth rate, relative growth rate and net assimilation rate recorded under 60 Gay radiation level were 40.25 g/plant/week, 4.25, 1.18 g/week, 0.0621g/g/week and 17.07 g/m2/week respectively.

• 디지털콘텐츠학회 논문지
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• 제13권3호
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• pp.421-429
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• 2012

최근 방사선 의료에서 중재적 시술의 확대로 인하여 시술 건수가 증가하고 있으며, 시술자에 따라 방사선 노출이 다르게 나타 날 수 있으며 시술자와 환자가 받는 방사선 피폭의 증가를 가져온다. 본 연구는 2011년 11월 01일부터 2012년 01월 31일 까지 경북지역 S대학 병원에 내원한 303명의 심장내과 환자를 대상으로 중재적 방사선시술을 시행한 시술자 5명에 따른 방사선 노출특성을 비교분석하였다. 투시시간의 경우 5명의 시술의의 평균 투시시간은 697.95초, cumulative DAP(exp)의 경우 평균 환자 면적선량은 $52,730mGycm^2$, total DAP의 경우 평균 환자면적선량은 $104,875.14mGycm^2$, acquired image의 경우 평균 영상은 855.52frame, exposure image의 평균 영상은 802.2frame로 나타나 통계적으로 유의한 차이를 보였다(p<0.05). 장비의 X선 노출 특성 즉, 투시시간, cumulative DAP(fluro), cumulative DAP(exp), total DAP, acquired image, exposure image는 서로 높은 상관관계를 보이나 cumulative DAP(exp)와 acquired runs는 상관관계를 보이지 않았다. 시술자와 가장 큰 비중을 차지하는 것은 투시시간으로 나타나 투시시간이 길어질수록 방사선 피폭이 증가함을 의미한다. 시술시 피폭선량은 시술자에 따라 시술능력과 경험, 시술의 난이도 및 정밀 시술여부와 관련 있으며, 혈관 조영의 횟수와 투시시간이 정해진 것이 아니어서 인위적인 조절이 어려운 부분이라 할 수 있다. 따라서, 중재방사선 절차를 수행하는 의료진의 실질 피폭을 합리적으로 평가하는 시스템이 필요하며, 불필요한 피폭을 줄이기 위해 시술자를 비롯한 방사선 작업종사자에 대한 자체교육과 훈련이 필요할 것으로 사료된다.