• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.1
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• pp.77-84
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• 2006

For a fire cause judgement this paper describes the heating characteristics of electric bare wire melted by AC current. The cower wires prepared for the experiment were 1.2[mm], 1.6[mm], and 2.0[mm] in diameter. Through the cross section analysis(CSA), it was confirmed that the dendrite structure grew at the angle of about 40[$^{\circ}$] or 60[$^{\circ}$] when the fusing current was applied to the wires. The larger the fusing current is, the more decreased the growth angle of the dendrite structure is. It was confirmed that the dendrite structure was arranged like the columnar structure.

• Fire Science and Engineering
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• v.13 no.2
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• pp.12-17
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• 1999

We intended to investigate combustion properties of rice bran dust. Combustion properties of h rice bran dust according to size distribution and amount were measured as temperature v variation with time using spontaneous ignition apparatus. Moreover, combustion properties w with blowing or without blowing condition were checked in order to investigate combustion p properties in spontaneous ignition apparatus according to flow condition of air. A As the mass and size of rice bran dust was increased, i띠ti외 smoldering temperature was l lowered. All of combustion forms were smoldering combustion. Initial smold얹ing temperature w was slightly lower with blowing condition than without blowing condition in spontaneous i ignition apparatus, which condition made heating value high.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.171.1-171.1
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• 2011

폐기물의 처리방법은 중간처리와 최종처리로 구분되며, 중간처리의 방법으로는 고형화, 생물학적 처리(소화), 화학적 처리(중화/침전/추출), 자원화 및 재활용, 소각/열분해용융/가스화 등이 있다. 최종처리 방법으로는 매립, 해양투기 등이 있으며, 과거에는 폐기물의 처리 방법으로 최종처리가 많이 이용되었으나 현재에는 지속가능한발전의 이념아래 폐기물의 자원화, 청정에너지의 생산 등을 이유로 전처리 기술이 많이 보급되고 있는 추세이다. 남원시에서 발생되는 생활폐기물은 2010년 통계에 따르면 하루 평균 약 43돈에 이르고 있으며, 매립지의 사용연수를 연장하기 위한 중간처리 방법이 검토되고 있다. 생활폐기물의 가장 일반적인 중간처리 방법으로는 소각, 열분해용융, 가스화 등이 적용될 수 있으며, 이와 같은 열적처리는 폐기물의 감용 및 감량 효율이 높은 중간처리 방법에 속한다. 이러한 열적처리를 위해서는 폐기물의 물리적 특성에 대한 조사 및 검토가 가장 먼저 선행되어야 하며, 본 연구에서는 남원시에서 발생되는 생활폐기물의 성상분류, 삼성분분석, 원소분석, 발열량분석 결과를 통해 가스화에 적합한 전처리 조건을 예측하였다.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.6
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• pp.72-79
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• 2002

The main objective of this study is to investigate the relationship between chemical structure and higher heating value of reformed diesel fuels by ultrasonic irradiation. In order to analyze the chemical structure changes of the reformed diesel fuels by ultrasonic irradiation, Proton nuclear magnetic resonance spectrometer(1H-NMR) was used and to analyze the effect of higher heating values of these diesel fuels, the bomb calorimeter was used. From the study, following conclusive remarks can be made. 1) The aromatic carbon percentages and higher heating values of the reformed diesel fuels by ultrasonic irradiation increased more than the conventional diesel ones. 2) The aromatics percentages and Branch Index(BI) of the reformed diesel fuels by ultrasonic irradiation decreased more than the conventional diesel ones. 3) The higher heating values on both for conventional fuel and reformed diesel fuels by ultrasonic energy irradiation is directly proportional to aromatic carbon percentages and inversely proportional to aromatic percentages and BI for these fuels.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.04a
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• pp.279-283
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• 2010

본 연구에서는 화재시 대규모 피해가 우려되는 승용차 밀집 공간을 가정하여 인접한 승용차로의 화재 전파 특성을 파악하기 위한 실물화재 실험을 실시하였다. 실험은 인접한 두 대의 승용차중 한 대의 차량에 화재를 발생시켜 화재가 성장되고 전파되는 과정을 분석하였으며, 산소소모율법을 적용한 발열량 측정이 동시에 이루어 졌다. 측정 결과 최대 열방출율은 약 9MW로 측정되어 선행된 승용차 한 대의 측정 발열량보다 약 2.5배이상 높은 범위의 값으로 평가되었다. 특히, 인접된 승용차로의 전파는 화재 발생후 약 3분 30초 경과후 창문으로 출화된 화염에 의하여 옆 차량에 화재가 전파되기 시작하였으며, 15분 경과후 완전히 화재가 전이되어 발달되었다. 따라서, 밀폐된 주차장에서의 화재시 발생초기에 가연 공간에서 화재가 진화가 이루어지지 않으면 약 3분 내에 다른 차량으로의 화재 전파가 우려 되며, 이후 급격한 피해를 줄 수 있는 상태로 화재가 성장하기 때문에 신속한 초기 대응이 필요함을 확인하였다. 이러한 실물화재실험에서 얻어낸 결과는 향후 여러 수치해석의 입력 조건으로 활용이 가능할 것이며, 화재 안전 설비 계획에 기본 자료로서 이용될 수 있을 것으로 기대된다.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.2
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• pp.261-266
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• 2015

Power system for renewable energy is composed of module, transform DC power into AC power inverter, control power flow and device for a charge of the grid-connected. Power system for renewable energy produce the most DC power, when this system is much insolation in summer and daytime. But if the certain temperature rises above, the essential grid-connected power inverter is take a nose dive. There, in this paper, we propose an improved reduction of heating system. In addition, selection of the most serious heat region and through analysis of temperature characteristics according to location and distance derive the optimal model.

• Clinical and Experimental Pediatrics
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• v.50 no.10
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• pp.1005-1010
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• 2007

Purpose : To determine the optimal time of high dose intravenous immune globulin (IVIG) treatment, we analysed the clinical characteristics and progress of a group of Kawasaki disease patients who had early treatment with IVIG. Method : A retrospective study was conducted of 188 patients with Kawasaki disease who were admitted to Yeungnam University Medical Center from January 2000 to December 2005. All patients were treated with a high dose IVIG and high dose aspirin for the initial acute phase treatment. The early treatment group consisted of 94 patients who received treatment before 5 days of fever, and the conventional group consisted of 94 patients who were treated on or after day 5. The patients' sex, age, laboratory findings, total duration of fever, duration of fever after initial IVIG, need for additional IVIG and coronary artery status were noted. Result : There were no significant differences between the two groups in sex ratio and age. No significant differences were noted in the level of WBC count, ESR, CRP, serum albumin, LDH, total duration of fever and coronary abnormality. But the value of ALT($151.8{\pm}17.3$ vs. $81.9{\pm}13.4$, P=0.002), duration of fever after initial IVIG ($3.8{\pm}0.5days$ vs. $2.1{\pm}0.2days$, P=0.003), and rate of additional IVIG (15.9% vs. 6.3%, P=0.037) were significantly higher in the early treatment group. There was no significant difference in initial dose of IVIG, but dosage of aspirin was lower in early treatment group (P=0.037). Conclusion : There is no evidence that early treatment of IVIG has greater efficacy in preventing cardiac sequelae than conventional treatment. In addition, early treatment is likely to result in a greater requirement for additional IVIG treatment.

• Pediatric Infection and Vaccine
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• v.7 no.2
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• pp.218-224
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• 2000

Purpose : In Korea, vivax malaria has been reemerged since 1993 after being abscent for more than 10 years. There are several possibilities of casuality of recent epidemic, although it is still unclear. The epidemiologic studies including case analysis and entomological reseach have been undertaken for a successful control measure. But, unfortunately those studies have been rarely dealt with cases of children. Therefore, this study was designed to figure out the characteristics of epidemiolgic and clinical features in children with indigenous vivax malaria. Methods : The study 21 cases below 15 years of age, who were diagnosed as vivax malaria and resided in kyounggi-do province area during 1998. 9~1999. 8. We retrospectively analyzed epidemiologic data concernig with occurrence of vivax, and clinical manifestations, abnormal laboratory findings and outcomes including therapeutic responses. Results : All cases were inhabitants of the endemic areas for vivax malaria in northwestern part of Kyonggi-do or western Kangwon-do, and Paju-gun was the most prevalent. Indigenous malaria cases of this study were more prevalent in children above 10 years old age, and in male. Seasonally, vivax malaria in children occurred throughout the year except January, March and November, and the incidence was the highest in July. Clinical manifestations revealed that 48 hour cyclic fever pattern was the major fever pattern, and other symptoms such as headache, vomiting, poor appetites, chilling, abdominal pain and diarrhea were concomitantly developed. And splenomegaly revealed the main abnormal findings on physical examination, and anemia was the most frequent abnormal finding in laboratory examinations. Young trophozoite was frequently observed on peripheral blood smears. The therapeutic responses of chlorquine were very good in all cases, and no recurrence developed in follow up cases. Conclusion : Geographical and seasonal occurrence distributions of indigenous vivax malaria cases in children were very similar to those of adults as followings; Inhabitants of the endemic region, more prevalent in male, and more common during the summer season. Clinically, 48 hour cyclic fever pattern, splenomegaly and anemia were most frequent and important manifestations in children cases, and clinical courses were not serious. On blood smears, young trophozoite was most dominantly examined in children. Generally, the therapeutic outcomes were excellent, and recurrences were not observed.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2002.05b
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• pp.275-276
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• 2002

CaO는 물과 반응하여 발열반응을 일으켜서 CaO에 코팅된 계면활성제를 용해시키며 그리고 규산소다에 흡착된 중금속과 유기물을 고정화 시키는 역할을 담당한다. 그리고 규산소다는 물과 가수분해하여 다공성이 되면서 중금속과 유기물 등을 흡착시키는 역할을 담당한다. 또 CaO에 코팅된 계면화성제는 기름과 반응성이 우수하므로 $80^{\circ}C$～$90^{\circ}C$에서 용해하여 기름과 반응하는 특성을 갖고 있다. 미분 슬래그는 보간 중에 암석화되는 과정을 도와 주므로 시간이 경과하면 pH가 점점 중성으로 변화하는 현상을 보여 주었다.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.10a
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• pp.351-354
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• 2003

최근 안전 분야에서 기능성 고분자 재료의 응용분야로서 첨단 전기전도성 고분자복합재료를 이용한 섬유상, 구형, flake 등 각종 형상의 금속, 흑연, carbon black, whisker 등의 전도성 filler를 고분자 matrix에 혼입하여 전도성 고분자를 성형가공하여 복합성형체를 제조하고 electrical hazard를 감소시키기 위한 정전기방지효과, 자기발열체, 전자기파 차폐효과 등의 특성을 나타내는 고분자 성형체상으로 가공된 소재로 화학공장, 산업설비, 각종 제조설비의 제조 공정용 제어, 과전류차단 및 외부 전자기파에 의해 발생되는 이상작동 등을 방지하는 안전시스템 소재용으로서 다양하게 사용되고 있다.(중략)