• Environmental Analysis Health and Toxicology
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• 제18권4호
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• pp.237-242
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• 2003

Single cell gel electrophoresis (SCGE) was used to the experiment with the variation on the amount of smoking and low dose radiation exposure to find how much the Lymphocyte DNA was damaged, and especially for whom smoke a lot(about 20 or more than 20 cigarettes a day) it was found to be highly damaged. While, the damage of 'not more than 20 cigarettes a day' was found to be not so much significant as like for whom smoke about or more than 20 cigarettes a day And, according to the different amount of the radiation exposure, the Lymphocyte DNA was found to be considerably damaged for 0-13m Sv (P<0.01), it was not able to prove the relationship between the DNA damage and the radiation exposure.

• Journal of Radiation Protection and Research
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• 제41권1호
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• pp.57-70
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• 2016

Background: Since the terminology 'radioactive consumer product' is not quite familiar to the public and is often considered as negative and detrimental things, the educational curriculum is essential for establishing reliability of nuclear energy related and for the development of better communication strategy of radiation risk with the public. To provide base data which is valuable for establishing efficient curriculum of education and training about radiation safety, it is necessary to apprehend the different level of awareness of radiation exposures classified by various consumer products. Materials and Methods: On November 2014, a question investigation about asking awareness level of radiation exposure from various consumer products was done for university students who are highly educated. The object students are studied at a four-year-course universities which is located at Daejeon City. Results and Discussion: Although the average awareness level is comparatively low, the awareness of senior students, who major in radiation, nuclear related departments and male students are relatively high. On the other hand, the awareness of freshman, sophomore, junior students, who do not major in radiation, nuclear related departments and female students are relatively low. It is necessary to provide various information to avoid unnecessary concerns and misconceptions about radiation exposure. Conclusion: This paper will be an instrument for efficient establishment of curriculum of education and training related with radiation safety.

• Journal of electromagnetic engineering and science
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• 제15권4호
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• pp.245-249
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• 2015

In this paper, a low-profile dipole array antenna with monopole-like radiation for on-body communications is proposed. The proposed antenna, operating in the industrial, scientific, and medical (ISM) band, is designed with consideration of the human body effect. By placing eight planar dipole antenna elements symmetrically around the z-axis, the proposed antenna achieves monopole-like radiation characteristics with a low profile. The antenna has overall dimensions of $0.44{\lambda}_0{\times}0.44{\lambda}_0{\times}0.013{\lambda}_0$ at 2.45 GHz in the ISM 2.45 GHz band (2.4-2.485 GHz) and a 10-dB return loss bandwidth of 4.9% ranging from 2.4 to 2.52 GHz.

• 천문학회보
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• 제44권1호
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• pp.84.3-84.3
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• 2019

We investigate 3D radiation-hydrodynamics (RHD) for surface convection of the solar-type low-mass stars (M = 0.8, 0.9, and 1.0 Msun). The outer convection zone (CZ) of low-mass stars is an extremely turbulent region composed of partly ionized compressible gases at high temperature. Particularly, the super-adiabatic layer (SAL), the top of the CZ is the transition region where the transport of energy changes drastically from convection to radiation. In order to accurately describe physical processes, a realistic treatment of radiation should be considered as well as convection. As a starting model, the initial stratification in the outer envelope calculated using the solar calibrations in the context of the standard stellar theory. When the numerical fluid becomes thermally relaxed, the thermodynamic structure of the steady-state turbulent flow was explicitly collected. In this presentation, we compared thermodynamic properties of turbulent convection of the solar-type low-mass stars.

• Journal of Radiation Protection and Research
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• 제29권1호
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• pp.9-15
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• 2004

방사선에 의해 유도되는 사람 말초혈액 림프구 미소핵 관찰빈도를 높이면서 생물학적 선량평가법으로서 활용 가능성을 확인하고자 본 연구를 수행하였다. 우선 5명의 건강한 사람으로부터 혈액을 제공 받아 선량영역을 0에서 800cGy로 하여 감마선$(^{137}Cs)$을 조사 한 후 김사와 아크리딘 오렌지 형광 염색하고 미소핵 출현빈도를 비교하였다. 아크리딘 오렌지 염색법을 이용하여 미소핵을 관찰하였을 때, 김사 염색법에 비교하여 적갈색의 비특이성 과립과 녹황색의 DNA가 붉은색의 세포질을 배경으로 명확히 구별되었을 뿐만 아니라 선량이 증가하면서 검출율도 높았다. 아울러, 말초혈액 T와 B-림프구에 대하여 선량영역을 0에서 50cGy로 하여 방사선을 조사한 후 미소핵 출현빈도를 아크리딘 오렌지 염색하여 김사염색과 비교한 바, B-림프구에서 선량이 증가하면서 적어도 2배 이상 높게 관찰되었다. 본 실험 결과, 사람 말초 혈액 B-림프구를 대상으로 한 아크리딘 오렌지 형광염색 미소핵 분석법은 저선량 방사선 인체영향 평가나 과피폭 선량추정시 활용이 가능 할 것으로 생각된다.

• Journal of Plant Biotechnology
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• 제30권3호
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• pp.293-299
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• 2003

The effects of low dosage ${\gamma}$-radiation on the cell growth and the formation of shikonin derivatives were investigated in callus cultures of Lithospermum erythrorhizon under different medium and light conditions. Gamma radiation significantly affected the cell growed and formation of shikonin derivatives, depending on the culture conditions. In the cell cultures grown on M-9 medium, 2Gy and 16Gy of ${\gamma}$-radiation increased the calli growth and the formation of shikonin derivatives, respectively under 16hr day light condition. When calli were cultured for 60 days in the dark after irradiation of ${\gamma}$-radiation, cell growth was increased at low dosage of 1Gy and 2Gy in LS medium containing BA 2mg/L and IAA 0.2mg/L. Interestingly, calli grown in M-9 medium by 2Gy irradiation for 60 days significantly stimulated the formation of shikonin derivatives(13.21mg/g cell fresh wt), which was approximately 6 times higher than untreated cells.

• Nuclear Engineering and Technology
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• 제56권2호
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• pp.568-574
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• 2024

The development of radiation-tolerant radio-frequency (RF) systems can be a solution for applications in extreme radiation environments, such as nuclear power plant monitoring and space exploration. Among the crucial components within an RF system, the low noise amplifier (LNA) stands out due to its vulnerability to TID effects, mainly relying on transistors as its main devices. In this study, the TID effects in the LNA using standard 0.18 ㎛ complementary metal oxide semiconductors (CMOS) technology are estimated and analyzed. The results show that the LNA can withstand absorbed radiation up to 100 kGy. The S₂₁, S₁₁, noise figure (NF), stability (K), and linearity of the third input intercept point (IIP3) slightly shifted from the initial values of 0.8312 dB, 0.793 dB, 0.00381 dB, 1.34406, and 2.36066 dBm, respectively which are still comparable to the typical performances. Moreover, the standard 0.18 ㎛ technology has demonstrated its radiation tolerance, as it exhibits negligible performance degradation in the conventional LNA even when exposed to radiation levels up to 100 kGy. In this context, simulation approach offers a means to predict the TID effects and estimate the radiation exposure limit for electronic devices, particularly when transistors are used as the primary RF components.

• Radiation Oncology Journal
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• 제35권4호
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• pp.380-384
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• 2017

Massive chylous leakage is a rare postoperative complication that can prolong hospital stay and cause secondary morbidities. Conservative management strategies are the treatment of choice; however, radiation therapy (RT) can be used as an alternative for cases that are refractory to conservative treatment. Herein, we report a 69-year-old female patient who suffered from massive chylous leakage after subtotal gastrectomy. Due to persistent massive chylous leakage, she was scheduled to undergo low-dose RT. Radiation was delivered with a daily dose of 1 Gy, using an anterior-posterior and posterior-anterior beam arrangement. The clinical target volume encompassed the entire lymph node area of the D2 dissection. RT was completed at the total dose of 8 Gy because the amount of chylous leakage declined rapidly. Percutaneous drainage tube was removed after 3 days of RT. The patient did not complain of any symptoms related to massive chylous leakage 2 years after the completion of RT.

• Journal of Photoscience
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• 제9권3호
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• pp.37-40
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• 2002

Astronauts are constantly exposed to space radiation at a low-dose rate during long-tenn stays in space. Therefore, it is important to determine correctly the biological effects of space radiation on human health. Space radiations contain various kinds of different energy particles, especially high linear energy transfer (LET) particles. Therefore, we have to study the relative biological effectiveness (RBE) of space radiation under microgravity environment which may change RBE from a stress for cells. Furthermore, the research about space radiation might give us useful information about birth and evolution of life on the earth. We also can realize the importance of preventing the ozone layer from depletion by use of exposure equipment to sunlight at International Space Station (ISS).

• 전기전자학회논문지
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• 제18권4호
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• pp.544-551
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• 2014

본 논문에서는 방사선 측정장치의 저준위 방사선 측정 알고리즘과 방사선량의 급격한 변화에 따른 장치의 반응 속도개선을 위한 알고리즘 및 장치의 구성을 제안한다. 저준위 방사선 측정의 측정 정밀도를 개선하기 위한 알고리즘은 방사선 측정센서로부터 수집된 펄스의 누적평균을 기준으로 하는 듀얼 윈도우 방사선 수치 측정법을 사용한다. 방사선량의 급격한 변화에 따른 장치의 반응 속도개선을 위한 알고리즘은 신규로 입력된 6초 동안의 데이터 패턴분석을 통한 듀얼 윈도우 방사선 수치 측정법을 사용한다. 제안된 알고리즘의 검증을 위한 하드웨어 장치로는 센서 및 고전압 발생부, 제어부, 충전 및 전원회로부, 무선통신부, 디스플레이부 등으로 구성되어 있다. 제안된 알고리즘에서 사용한 듀얼 윈도우 방사선 수치 측정법을 실험한 결과, 기존 5uSv/h 수준의 저선량 한계에서 대체로 불확도가 낮아지고 선형성이 개선됨을 확인할 수 있었다. 또한 급격한 방사선량의 변화에 대한 장비의 반응속도 개선에 대해 실측실험을 통해 6초 이후에 변화된 수치가 반응함을 확인하였다. 따라서 제안된 알고리즘이 급격한 변화에 따른 장치의 반응속도가 개선됨을 확인할 수 있었다.