• Proceedings of the KIEE Conference
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• 2007.11b
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• pp.112-114
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• 2007

전력선에서 발생하는 자속으로 인해 주변 통신선이나 도체에 영향을 주는 유도장해는 특히 전력선의 지락사고 시 전력선에서 발생한 큰 자속이 주변 통신선 등에 쇄교하여 높은 전자유도 전압을 발생한다. 선로 정수를 계산하여 자체적으로 인덕턴스와 정전용량 계산이 가능한 EMTP를 통하여 154kV 전력선의 실측데이터를 바탕으로 1선 지락사고 시의 전력전송 등가모델을 구현하여 주변 통신선에 유도되는 전압을 시뮬레이션을 통해 자료를 얻는다. 이론적으로 알고 있는 유도장해를 실험을 통하여 확인함을 이 논문의 목표로 한다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1996.05a
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• pp.131-137
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• 1996

HTPB/AP/Al이 주성분인 2종의 혼합형 추진제를 대상으로 4종의 금속선(Ag, Cu, Al, Ni-Cr)윰 각각 삽입하여 금속선의 직경(0.1~0.8mm)과 연소 압력에 따른 금속선에 인접한 고체 추진제의 연소 속도 증가비($r_w$/$r_sb$)와 압력 지수(n)의 변화를 고찰하였다. 금속선을 추진제에 삽입함으로써 추진제의 $r_w$/$r_sb$ 는 크게 중가하였고, 1000 psia의 압력에서의 최대 6.59배 증가하였다. 그러나 녹는 점이 비교적 낮은 Al 선이나 Ag선은 금속선 직경이 작아짐에 따라 한계 직경에서 $r_w$가 급격히 감소하는 최대값이 존재하였다. 자연 발화 온도와 금속선으로 전달되는 열원인 연소 기체 불꽃 온도로 구성된 무차원군을 Buckingham pi 정리에 의해 구해진 $r_w$/$r_sb$ 에 대한 기존의 무차원 실험식에 추가로 적용하여 계산해 본 결과, 자연 발화 온도는 고려하지 않고 금속선의 녹는 점과 연소 기체의 불꽃 온도를 무시한 Hsing 의 실험식에 의해 계산된 결과보다 표준 편차가 45%이상 줄어듬을 알 수 있었다.

• Journal of the Korean Magnetics Society
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• v.2 no.2
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• pp.105-113
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• 1992

조성이 Mn$_{x}$Zn$_{1-x}$ Fe$_{2}$O$_{4}$ 훼라이트(x=0.75, 0.52)를 pusher type 연속 전기로를 이용하여 질소 분위기하에서 1360 .deg. C 로 3시간 동안 소결하여 얻어냈다. 본 연구에서는 스피넬 구조인 Mn-Zn 훼라이트의 FMR(Ferrimagnetic Resonance) 스펙트럼 특징과 초기투자율과의 상관성을 조사하고자 EPR X-band 스펙 트로미터를 이용 9.50 GHz의 microwave frequency에서 FMR 실험을 수행하였다. FMR 공명흡수선은 주 자기공명 흡 수선외에 낮은 자기장에서 약한 subsidiary 공명흡수선을 나타내는데 온도변화에 따른 주 자기공명 흡수선과 sub- sidiary 공명흡수선(제2, 제3 공명흡수선)의 세기, 공명선폭, g값 등의 온도 의존성을 연구함으로써 제2 공명흡수 선이 나타나는 원인을 분석하였으며, 자기공명 흡수선의 g값, 자기공명선 세기, 그리고 공명선폭과 초기투자율의 상관성을 연구하였다. 실험 결과 주 자기공명 흡수선의 g값, 자기공명선 세기, 공명선폭은 초기투자율 값과 밀접 한 관련이 있음을 확인할 수 있었다.었다.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.4
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• pp.412-421
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• 1998

Physicochemical and microbiological properties of red beans, soybeans, barleys, and corns irradiated by gamma-ray at 1.2 kGy, 10.1 kGy, or 30.5 kGy were investigated. Moisture content and crude lipid content of the irradiated cereals showed no significant difference from the nonirradiated group. TBA values of corns irradiated at 30.5 kGy increased. Gamma irradiation reduced the numbers of mesophilic and psychrotrophic bacteria in the cereals. Yeasts and molds were reduced below detection levels even at 1.2 kGy dose-irradiation. There was no significant difference in reducing sugars between the irradiated cereals and the nonirradiated ones except corns. Stachyose, raffinose, and sucrose of soy beans and sucrose of barleys increased by 30.5 kGy dose-irradiation. Loss of riboflavin content of the irradiated samples was not observed except red beans irradiated at 30.5 kGy. In Hunter's color, b value of the red bean powder increased but L value of the soybean powder decreased by the Irradiation. L, a, and b values of the barley powder slightly increased under 30.5 kGy dose-irradiation and b value of the corn powder decreased under 10.1 or 30.5 kGy-dose irradiation.

• Journal of the Mineralogical Society of Korea
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• v.4 no.1
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• pp.11-21
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• 1991

XRD patterns of biedellite-nontronite and saponite-iron saponite series were investigated using one-dimensional pattern simulation method. Ethylene-glycolate smectites show stronger 002 and 003 reflections than hydrated specimens do. The intensities of the 002 and 003 reflections change systematically as a function of Fe enrichment in both types of smectites. The intensity ratio of 002/003 increases with increasing. Fe in both dioctahedral to the higher scattering factor of Fe than those of Al and Mg, and the scattering power of various smectites can be compared quantitatively by calculating the scattering factors of octahedral cations. Interlayer cations cause less effect on XRD profile than octahedral cations as Fe do. Although 001 reflections provide informations about the overall scattering power of the octahedral sheet, some ferrous dioctahedtal smectite cannot be distinguished unambiguously from trioctahedral smectites on the basis of XRD profile. Simulation showed that heterogeneous smectites exhibit 001 intensity distribution that is almost identical to that of homogeneous smectites having the average composition of heterogeneous ones. The broadening of 001 reflections may not be useful in evaluating the degree of heterogeneity of smectite unless other factors affecting the broadening are well known.

• Progress in Medical Physics
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• v.12 no.2
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• pp.161-169
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• 2001

For the head and neck radiotherapy, the technique of half beam using independent collimator is very useful to avoid overlapping of fields particularly when the lateral neck fields are placed adjacent to anterior supraclavicular field. Also abutting photon field with electron field is frequently used for the irradiation of posterior neck when tolerable dose on spinal cord has been reached. Using 6 MV X-ray and 9 MeV electron beams of Clinac1800(Varian, USA) linear accelerator, we performed film dosimetry by the X-OMAT V film of Kodak in solid water phantom and the dose distribution at beam center of 2 half beams further examined according to depths(0 cm, 1.5 cm, 3 cm, 5 cm) for single anterior half beam and anterior/posterior half beam. The dose distribution to the junction line between photon and electron fields was also measured. For the single anterior half beam, the absorption doses at 0.3 cm, 0.5 cm and 1 cm distances from beam center were 88%, 93% and 95% of open beam, respectively. In the anterior/posterior half beams, the absorption doses at 0.3 cm, 0.5 cm and 1 cm distances from beam center were 92%, 93% and 95% of open beam, respectively At the junction line between photon and electron fields, hot spot was developed on the side of the photon field and a cold spot was developed on that of the electron field. The hot spot in the photon side was developed at depth 1.5 cm with 7 mm width. The maximum dose of hot spot was increased to 6% of reference doses in the photon field. The cold spot in the electron side was developed at all measured depths(0.5 cm-3 cm) with 1-12.5 mm widths. The decreased dose in the cold spot was 4.5-30% of reference dose in the electron field. With above results, we concluded that when using electron beam or independent jaw for head and neck radiotherapy, the hot and cold dose area should be considered as critical point.

• The Korean Journal of Zoology
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• v.8 no.2
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• pp.42-46
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• 1965

가물치 (Ophicephalus argus CANTOR) ♂♀를 재료로 하여 두 실험군으로 나누어서 대조군에 부치사량인 25-${\gamma}$의 137Cs-${\gamma}$ 선을 조사하고 실험군에는 250${\gamma}$의 137Cs-${\gamma}$선을 조사 즉후 adrenaline (0.5cc/80g$\pm$18%)을 매일 투여하여 약 23$^{\circ}C$에서 사육하면서 혈청단백질의 전기영동상과 총혈청단백질의 변화를 1, 4, 7, 10 , 13 및 1일구간으로 분리 즉 시일적 경과로 조사하였다. 한편 가물치에서의 ${\gamma}$선 치사량은 310${\gamma}$이다. 1) 양군에서 일반적으로 1, 4, 7, 10 및 13 일구에 현저한 albumin 분설의 감소가 나타났다. 즉 대조군인 adrenaline 비투여 대조군에서 a1 및 a2 globulin 분설의 증가와 실험군이 adrenaline 투여 대조군에서 a1 및 $\beta$-globulin 분설의 증가에 다른 albumin 분설의 감소가 나타났다. 따라서 A/G 비고 역시 시일적 경과에 따라 감소된 치를 나타내었다. 그러나 특히 adrenabine 투여 대조군의 1 일간에서 A/G비가 현저하게 감소의 지체성을 나타내었다. 2) 총혈청단백질량은 양군에서 일반적으로 1, 4 및 7일구에서 현저하게 감소되나 13 미치 16 이구에서 가물치의 정상치로 근접된 치를 나타내었다. 그러나 특히 adrenaline 투여 조사군에서 4 및 7일구에서 현저하게 감소의 지체성을 나타내었다. 3) 상기의 결과로 미루어보다 명백하게 혈청단백질에 미치는 adrenaline 처리의 방어효과가 ${\gamma}$선 조사후 특히 초기상태에서 현저하게 초래된다고 생각도니다.

• Korean Journal of Veterinary Research
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• v.33 no.4
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• pp.649-655
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• 1993

A series of experiments on the effects of ${\gamma}-irradiation$ was performed to reveal the pathogenicity of ${\gamma}-irradiated$ oocysts of E tenella from Cobalt-60 and its progeny. The SPF chickens were inoculated with differnt doses of radiation and inoculum. The level of 100 Gy ${\gamma}-irradiation$ from $^{60}Co$ and the level of inoculum with $1{\times}10^4$ oocysts were recognized more pathogenic than those of the other groups by comparison of body weight gains, blood in feces and lesion scores. The signs of blood in feces, lesion score and the number of excreted oocysts in the feces were revealed as the lowest in the group of the ${\gamma}-irradiated$ oocysts, the average in the group of the 1st and the 3rd progeny, and the highest in the group of non-irradiated oocysts of E $tenell\grave{a}$. The body weight gain of the group immunized with ${\gamma}-irradiated$ oocysts of E tenella was higher than those of the non-irradiated, the 1st and 3rd progeny groups. The body weight gain of the groups immunized with the 1st and the 3rd progeny of E tenella were higher than that of the non-irradiated group. The feed conversion ration of the group immunized with ${\gamma}-irradiated$ oocysts of E tenella was lower than those of the non-irradiated, the 1st and the 3rd progeny groups. The feed conversion ratios of the group immunized with the 1st and 3rd progeny of ${\gamma}-irradiated$ oocysts were lower than that of the group infected with non-irradiated E tenella. The anticoccidial index(ACI 190.6) in the chickens immunized with the ${\gamma}-irradiated$ oocysts of E tenella and those(ACI 142.8 and 107.4) of the 1st and the 3rd progeny groups were higher than that (ACT 87.4) of the group infected with non-irradiated E tenella. It was thought that the pathogenicity of ${\gamma}-irradiated$ E tenella would be recovered according to increase the number of generation passaged in chicken.

• Journal of the Korean Magnetics Society
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• v.15 no.2
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• pp.81-84
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• 2005

The origin for the charge disproportionation (CD) transition in polycrystalline $La_{1/3}Sr_{2/3}FeO_{2.96}$ was examined using X-ray diffraction and the external field $M\ddot{o}ssbauer$ssbauer spectroscopy. In order to see how the external magnetic field affects the CD state above its transition temperature, an external magnetic field of up to 6 T was applied either parallel or perpendicular to the $\gamma-ray$ direction with the sample temperature fixed at 225 K, which was above the CD transition temperature. Without an external magnetic field, a completely paramagnetic singlet was obtained in the temperature range of the averaged valence state above the transition temperature, which was interpreted as coming from the average valence $Fe^{3.6+}$. In the longitudinal geometry, a magnetic Zeeman with its intensity ratio 3:0:1:1:0:3 is superimposed to the central singlet. In the transverse geometry, however, the central singlet disappears and only a magnetic component with its intensity ratio 3:4:1:1:4:3 emerges. The existence of a singlet is understood as an evidence of the fast electron-transfer among Fe ions. Since the singlet still exists under the magnetic field, the application of an external field has little effect on the conduction mechanism of hopping electrons.

• Korean Journal of Plant Tissue Culture
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• v.27 no.2
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• pp.143-148
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• 2000

This study was carried out to know the optimum dose of gamma-ray for the induction of mutation in vitro and the characteristics of the mutants induced by gamma-ray in persimmon (Diospyros kaki Thunb.). The LD50 (50% lethal dose) for in vitro shoots of the cultivar, Nishimurawase was between 1 krad and 2 krad and about 1 krad for the cultivar, Ichikikeijiro. As the dose of gamma-ray increased, the length of shoots decreased and necrosis of buds increased. For the cultivar, Nishmurawase, 37.5∼58.3% shoots rooted and the rooting rate and the number of roots per shoot was low in high gamma-ray. The irradiated young plants which were grown in the growth cabinet for 6 weeks were shorter in shoot length and had more branches than non-irradiated plants. The survival rate of irradiated plants grown in the green house for 3 months was 33%, while 77% for control plants.