• Journal of Life Science
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• v.23 no.8
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• pp.963-969
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• 2013

Although it is popularly believed that vitamin C protects cells from various genotoxicants, the degrees and mechanisms of itsprotective actions are not fully understood. In this study, vitamin C's protective effects against various genotoxicants were quantified, together with subsequent analyses on the mechanisms of these protective effects. Comet assay was employed to measure the degree of DNA damage in Chinese hamster ovary cells (CHO-K1) exposed to five genotoxicants, $H_2O_2$, $HgCl_2$, N-methyl-N-nitro-N-nitrosoguanidine (MNNG), 4-nitroquinoline-1-oxide (4NQO), and UV-irradiation. In cases cells were treated with $H_2O_2$, $HgCl_2$, and 4NQO together with vitamin C, the damage to DNA decreased to the level of the control group. In cases of UV-irradiation, the protective effect of vitamin C appeared, but did not reach the control levels. Interestingly, vitamin C did not have protective effects against the genotoxicity of MNNG. The degrees of DNA damage of cells treated with vitamin C prior to exposure togenotoxicants were 28~49% lower than those of cells treated with vitamin C after being exposed to genotoxicants. In conclusion, vitamin C had strong antioxidanteffects against genotoxicants by being a primary antioxidant blocking genotoxicity reaching the cells, rather than being a secondary antioxidant acting on post-exposure DNA repair processes. However, vitamin C's protective effects appearto be limited, as there are genotoxicants, such as MNNG, whosegenotoxicityis not affected by vitamin C. Therefore, the results of this study warrant furtherstudies on toxic mechanisms of genotoxicants and their interactions with protective mechanisms of vitamin C.

• Journal of radiological science and technology
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• v.23 no.1
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• pp.77-80
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• 2000

전신 ${\gamma}$-선 조사전 Grifola umbellata(Gu) 추출물의 단일 투여가 생쥐의 생존율, 체중, 기관 무게 및 혈액세포에 미치는 효과를 조사하였다 ${\gamma}$-선 조사 24시간 전에 Gu 추출물을 복강 투여하였을시, ${\gamma}$-선을 조사한 생쥐의 40-day 생존율을 65.5%에서 78.6%로 증가시켰다. Gu 추출물의 투여는 ${\gamma}$-선 조사에 의한 비장과 흉선의 무게 감소를 완전히 막아주었다(P<0.05, P<0.01) 또한 이와 유사하나 다소 적은 방사선 방호효과가 Gu 투여군의 고환에서도 관찰되었다(P<0.05). Gu 추출물의 투여는 ${\gamma}$-선 조사시 나타나는 조사 후 7일째까지의 백혈구와 림프구수의 현저한 감소를 지연시켰고, 회복속도를 촉진시켰다. 또한 21일째후의 적혈구수의 회복을 촉진시켰다. 이와 같은 결과에서 Gu 추출물의 방사선 방호효과를 알 수 있다.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.478-478
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• 2023

우리나라는 기후변화로 인해 태풍과 집중호우에 의한 산지재해 피해가 증가하고 있다. 이러한 산지재해를 저감하기 위해 토석류 수치모의를 하여 피해규모를 예측하거나 저감시설을 설치한다. 토석류 저감시설에는 사방댐, 방호벽, 유도수로 등이 있다. 국내에서는 사방댐을 많이 설치하고 있으나 사방댐을 설치할 시 주변 시설물의 규모와 위치를 고려해야 하는 어려움이 있다. 본 연구에서는 토석류를 저감하기 위한 시설 중 사방댐의 대안으로 방호벽을 설치하여 저감효과를 분석하였다. 2022년 8월 토석류 피해가 발생한 강원도 횡성군을 대상지역으로 선정하고 수치 지도를 이용하여 DEM자료를 구축하였다. 그리고 토석류 수치모의가 가능한 FLO-2D 모형에 적용하여 유동특성을 분석하였다. 또한 저감효과를 분석하기 위해 방호벽을 창고 주변과 주택 주변에 설치하여 해당 위치에서의 유동특성을 비교·분석하였다. 방호벽을 설치하고 토사가 퇴적되기 시작한 부분을 고려하여 설치한 후 건물 주변에서의 토석류 저감효과를 분석한 결과 창고 주변과 주택 주변에 단일로 설치하여 저감효과가 나타났으나 한계점이 나타났다. 한계점을 보완하고자 방호벽을 이중으로 설치하고 모형을 적용하여 저감효과를 비교·분석하였다.

• Defense and Technology
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• no.2 s.288
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• pp.68-79
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• 2003

화학전에서 군부대 및 민방위 등을 제외하고는 대다수 시민들이 화학방호대책을 준비하기에는 어려운 것이 사실이다. 준비된 방호수단이 없는 가운데에서 화학공격 또는 테러를 당할 경우, 최소한의 방호대책을 강구하기 위해서는 주변에서 쉽게 구할 수 있는 일반물자류 중 그 역할을 할 수 있는 대체가능물자류를 확보하는 것이 중요하다. 따라서 이번 연구는 이런 대체물자류의 선정 범위 및 그 재질의 화학방호성능을 알아보는 기초적인 연구를 실시하는데 목적이 있었으며, 대체가능물자를 선택하는데 있어 기초자료를 제공하고자 하였다.

• Journal of the Korean Society of Radiology
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• v.7 no.3
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• pp.239-244
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• 2013

Radiation were seriously damaged on liver functions. Blueberry was fruits that contains Vit A, Vit c, Vit E, follic acid, ${\beta}$-carotene, and anthocyanin. The purpose of this study was to evaluate the protection effects of blueberry the liver functions. Irradiation dose was used to 4 Gy (Linac 6 Mev) X-ray Treatment device Experiment animals was used to 7 rats in each groups. It was investigated liver functions that contains TP, ALB, GLOB, ALT, ALKP and CHOL. We showed that Blueberry was not recovery effects on radiation-induced liver functions. But, Statistically significant value was showed ALB (p>0.01) and ALT (p>0.1). It was concluded that blueberry was not used to recovery materials on radiation-induced liver functions.

• Journal of Radiation Protection and Research
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• v.7 no.1
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• pp.11-16
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• 1982

Cysteamine(Mercaptoethyiamine, MEA), S,2-Aminoethylisothiouronium Bromide. HBr (AET), and S-(2-Aminoethyl) Dihydrogen Phosphorothioate (WR-638) were prepared and radioprotective effects of these chemicals and their combinations against $^{60}Co$ ${\gamma}-ray$ radiation were studied ,in irradiated ICR mice. Intraperitonially administered chemicals or their combinations resulted drug deaths in cases of MEA, AET, and their combinations, whereas there were a slight or no drug death in cases of WR-638 and the combination of AET with WR-638. All tested chemicals and their combinations yielded radioprotective effects against $^{60}Co$ $\gamma-ray$ radiation. An additive radioprotection effect was observed in case of the combination of AET with WR-638.

• 방재와보험
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• s.106
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• pp.27-32
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• 2005

이 글은 The Hazardous Installation Directorate의 최우수 조사관인 Alan Tyldestey와 Atkins에서 화재안전 컨설턴트로 근무하고 있는 Peter Rew와 Richard Houlding가 위험물저장소의 화재방호 비용효과분석에 관해 발표한 연구보고서를 번역한 것이다.

• Journal of the Korean Society of Radiology
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• v.15 no.3
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• pp.313-320
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• 2021

This study evaluates the radiation protection effects of Schizonepeta tenuifolia water extract on white rat by gender. Schizonepeta tenuifolia contains polyphenol and flavonoid, which are typical substances that remove free radical. Thus, to determine the effectiveness of radiation protection, the Schizonepeta tenuifolia water extract was administered to Sparaqu-Dawely (SD) rat males and females for two weeks, followed by hematological analysis, analysis of changes in the length of the small intestine villi length, and SOD activity evaluation. The male rat in ST+IR group showed a slightly greater recovery of platelets than the IR group. The ST+IR group also showed a higher platelet recovery capability than the IR group. lymphocyte showed that male and female rat ST+IR groups have higher resilience than IR groups likewise platelet. After irradiation, the villi length of the male rat and female rat decreased less in ST+IR group than in the IR group, indicating that the villi length of all genders was less damaged. This result confirmed that the Schizonepeta tenuifolia water extract had a radiation protection effect.

• Journal of the Korea Society for Simulation
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• v.30 no.1
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• pp.55-63
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• 2021

As a study on ballistic protection performance of a weapon system that is used in combat simulation, this paper aims to propose an improvement effect of the ballistic protection performance varying with incident angle of a bullet. For this, live-fire ballistic tests were performed to determine either complete penetration(CP) and partial penetration(PP) of three types of general armor plates made of uniformly rolled steel plates against a small caliber threat using 5.45 mm bullets with various speed. The major test parameter was the material of the weapon system and incident angle of the bullet with the target. Further, to quantitatively analyze the ballistic protection performance, three existing measurement methods were used for ballistic limit velocity. The test results showed that the ballistic protection performance with the incident angle of 30 degrees was 4% to 14% varying with the material of the armor plates greater than that of 0 degrees, which was approximately 1.1 times the performance improvement on average when compared to the conventional angle of incidence of the 0 degree. Those test results are expected to contribute to developing a more realistic combat simulation addressing the parameter improving the ballistic protection performance of an armor plate.

• Defense and Technology
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• no.4 s.242
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• pp.82-87
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• 1999

전투원(전투병사) 개인방호체계는 각개병사와 병사들이 전술적 환경에서 사용하기 위해 착용, 소모, 휴대하는 모든것을 포함하는 방호체계들의 시스템이다. 이러한 전투원 개인방호체계의 현대화 노력은 "위력", "지휘 및 통제", "생존성", "유지능력", "기능성"을 극대화하고 전투원 체계들을 디지털 전장에서 통합함으로써 전투상승효과를 달성할 수 있다