• Progress in Superconductivity and Cryogenics
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• v.4 no.1
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• pp.110-113
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• 2002

The high-tc superconducting fault current limiters (SFCL) are studied worldwide to be classified as resistive type or inductive type such as magnetic shielding type and dc reactor type. This Paper deals with an open core type SFCL, a kind of magnetic shielding type SFCL. We manufactured a 30 kVA open core type SFCL. It was modified from the old one with a rated power of 8 kVA. We stacked four superconducting tubes as magnetic shielding material and used the same primary winding as the old one. The experiments were performed with a maximum source voltage of 1 kV. The results show that the fault current in the source voltage of 1 kVrms was reduced to be about 105 Apeak, which was calculated to be about 22 % of the fault current in the system without an SFCL.

• Korean Journal Plant Pathology
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• v.12 no.1
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• pp.132-136
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• 1996

오존에 의한 식물체의 가시피해 발현 이전에 나타나는 비가시적 피해를 찾아내기 위하여 적외선 열화상장치(infrared thermography)를 이용하여 하루 8시간씩 0.3 ppm 오존에 노출된 나팔꽃(Ipomoea purpurea)잎표면의 온도분포 변화를 조사하였다. 노출 첫날에는 온도분포의 뚜렷한 변화를 볼 수 없었다. 노출 2일째, 오존 노출 2시간 결과후, 완전히 자란 제3엽의 특정 부분에서 급격한 온도분포 변화를 보였으며, 그로부터 약 4시간 경과 후에 동일 지점에서 최초의 가시적 피해가 발생했다. 급격한 온도분포 변화를 보인 부분과 최초 가시피해가 발생한 부분이 일치한 점은 가시피해 발생과 그 이전의 온도분포 변화가 밀접하게 상관되어 있다는 것을 의미한다고 하겠다. 잎표면의 열화상 분석방법을 대기오염원에 의한 식물체의 가시피해 발현 이전에 진행되고 있는 비가시적 반응의 조기진단에 적용할 수 있으며 생태환경 친화적인 대기 환경관리를 위한 대기오염원은 배출조절용 생체반응기(biosensor)로 이용 가능하겠다.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.1
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• pp.79-85
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• 1983

The greenhouse bulk curing and drying system utilization of the direct solar energy was tested to evaluate that how much fuel could be saved for curing flue-cured tobacco at the Dae Gu Experiment Station (North latitude : $35^{\circ}$49'), in 1979-1982. The air temperature and total radiation were 19.0 to 38.5$^{\circ}C$ and 1311.0 to 1412.7 cal/$\textrm{cm}^2$/day during the 4 replicated curing test, respectively. The greenhouse bulk curing and drying system was able to cut fuel consumption by 32% compared with the conventional bulk curing barn. We could obtain almost same utilization efficiency of solar energy in 1982 compare with normal year, mainly increasing the heat receiving area.

• Korean Journal of Animal Reproduction
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• v.22 no.2
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• pp.163-169
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• 1998

본 실험은 체외 생산된 소 배반포기배에 대한 laser drilling 처리가 배의 부화율에 미치는 영향을 조사하고자 실시하였다. 그 결과는 다음과 같다. 소 수정란의 체외 발달율을 조사하였던 바, 82.3%의 난할율( 2-세포기)과 체외수정 후 배양 7일째에 32.6%의 배반포 발달율을 나타내었다. 이렇게 생산된 배반포기배에 laser drilling 효과를 조사하였던 바, 처리 후 24시간째의 부화진행율(90.0%)은 대조군(44.4%)보다 유의하게 높게 나타났다(p<0.0001). 또한, 처리 후 48시간째의 부화율(68.0%)도 대조군(33.3%)보다 유의하게 높게 나타났다. 이러한 결과는 laser drilling이 체외 생산된 소 배반포기배의 부화진행율과 부화율을 유의하게 증가시킬 수 있다는 것을 알 수 있었다(p<0.001).

• Journal of the Korean Ceramic Society
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• v.26 no.2
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• pp.258-266
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• 1989

The effects of grain size and dopant ZnO on the photoelectrochemical conversion in TiO2 ceramic electrodes have been investigated. The photocurrent increases with increasing grain size in the undoped TiO2 ceramic electrode. In ZnO-doped TiO2 electrodes, the photocurrent decreases with increasing ZnO up to 0.4 wt% due to decrease of donor concentration, and then with further addition of ZnO, photocurrent increases according to the formation of second phase. However, the photoresponse appears at wavelength of 420nm, which is very close to the energy band gap of TiO2, regardless of grain size and amount of ZnO.

• Journal of the Korea Institute of Military Science and Technology
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• v.7 no.2 s.17
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• pp.109-117
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• 2004

We synthesized energetic prepolymer(2-nitrato ethyl oxirane, NEO) for plastic-bonded explosive and measured its thermodynamic parameters. 2-Nitrato ethyl oxirane(NEO) as a monomer was synthesized from 4-butene-ol, the first-step was preparation of 1-nitrate-3-butene and second-step was synthesized 2-nitrate-ethyl oxirane from 1nitrate-3-butene and then polymerized by cationic ring opening polymerization. The unreacted monomer concentration was measured by GC. The thermodynamic parameters were obtained from the ceiling temperature(Tc) values of 1 mole monomer at each reaction temperature. We varied feed rate of monomer, concentration of initiator and monomer to control molecular weight and polydispersity of perpolymer(NEO). Number average molecular weight(Mn), polydispersity(PD), and glass transition temperature(Tg), viscosity of prepolymer(NEO) were 2000, 1.07, $-55^{\circ}C$ and 300 poise respectively.

• The Korean Journal of Mycology
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• v.23 no.4 s.75
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• pp.305-309
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• 1995

To investigate optimal conditions for the protoplast formation and regeneration of Phanerochaete chrysosporium, preparations of three enzymes were used to liberate protoplasts from its 20 hrs-old mycelium on cellophan membrane covered agar media. Novozym 234 alone with 0.6M sucrose was the most effective for isolation of protoplasts from the mycelium with 3hrs incubation time at $39^{\circ}C$ in shaking condition of 120 rpm. The poly-R medium stabilized with 0.6M mannitol was the best for regeneration of the protoplasts.

• Korean Journal Plant Pathology
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• v.12 no.4
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• pp.459-462
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• 1996

예년과는 달리 6월 중순부터 7월 중순까지 낮은 기온과 잦은 강우로 인한 음습한 날씨가 지속되었던 전남지방의 온실멜론에서 노균병이 격발하였다. 올해 전남지역에서 심하게 발생한 노균병의 병징은 다각형의 모무늬 외에도 불규칙한 대형의 부정형 무늬를 형성하였으며, 이러한 급성형 병징들은 주로 개화기 무렵 아랫잎에서부터 나타나기 시작하여 병이 진전됨에 따라 윗쪽으로 진전되었고 병반이 뭉쳐져 잎을 급속하게 고사시켰다. 표본 조사한 12개 농가의 시설 하우스에서 재배되고 있는 온실멜론의 노균병 이병엽율은 1%에서 100%까지 다양하였으며 수확을 전혀 못한 농가도 있었다. 각 농가에서는 노균병의 방제를 위하여 발병초기부터 농가당 최소 3회에서 최고 8회까지 살균제를 살포하는 방제 노력을 기울였으나 정확한 노균병 진단의 실패와 적정 약제 선정의 실패로 혼선을 빚어 방제효과는 높지 않았으며, 농약의 남용과 오용이 병방제에서 심각한 문제점으로 드러났다.

• Journal of Korean society of Dental Hygiene
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• v.22 no.5
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• pp.341-346
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• 2022

Objectives: This study was conducted to analyze the relationship between smoking and denture wear in the elderly individuals aged 65 years and older, and a total of 3,112 people were included. Methods: A complex sample chi-square test was performed for denture wear according to general, smoking, and smoking-related characteristics. Factors related to denture wear were assessed using multiple logistic regression analysis. Results: Among non-smokers, present smokers were 4.192 times more likely to wear dentures, and former smokers were 2.195 times more likely to wear dentures. The average number of daily past smokers was 0.564 times less likely to wear dentures if they smoked 15 cigarettes or less per day. Conclusions: Smoking among the elderly and wearing dentures are related, and it is necessary to develop and utilize a smoking cessation education program considers socioeconomic characteristics.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.2
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• pp.145-153
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• 2004

H$_2$SO$_4$ and citric acid were used as additives for the electrokinetic remediation experiment to increase removal efficiency of $^{137}$ Cs and $^{60}$ Co from the radioactive soil waste stored for more than 10 years. The average effluent velocity discharged from the elctrokinectic remediation experimental column was 2.0${\times}$10$^{-2}$ cm/min and the discharged soil wastewater volume for 10 days is 3.6 pore volume of the column. 97% of $^{60}$ Co in the column was decontaminated for 10 days of operation, while only 54% of $^{137}$ Cs was decontaminated. These results are considered that the absorption equilibrium coefficient of $^{137}$ Cs is higher than that of $^{60}$ Co. The predicted values of the residual concentration by the proposed mathematical model were well coincided with the experimental results within the experimental error range