• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2001.11a
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• pp.105-108
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• 2001

전기화재의 출화 형태는 i) 전기 배선 및 전기 기기에 의한 출화, ii) 누전에 의한 출화, iii) 정정기 불꽃에 의한 출화 등이 있다. i)과 ii)는 전기의 통전 또는 standby mode에서 출화된 화재를 말하며, iii)은 축적된 전하의 이동에 의해 발생한 화재를 말한다. 그리고 출화 원인은 단락, 과부하, 반단선, 트래킹과 흑연화 현상, 누전, 접촉 불량 및 아산화동 증식 발열 현상, 방전, 정전기 불꽃, 은 이동 등이 있다.(중략)

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.345-351
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• 1996

The study on the properties of low-heat cement that hear of hydration is relatively lower than that of ordinary portland cement and concrete made of this low-hear cement has been performed to test the hear of hydration and compressive strength, chemical resistance of concrete using low-hear cement to compare with concrete using other several typers of cements.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.138-139
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• 2012

본 논문에서는 고주파 공진형 인버터 접속의 가열 코일로부터 비접촉 상태로 전자유도 와전류를 구조물에 가하여 발열하는 공진형 인버터를 이용한 유도가열 방식의 최적설계를 제안하였다. 설계한 시스템 인버터는 스위칭주파수 20[kHz] 대역에서 동작하는 하프-브리지 고주파 직렬 부하 공진형이며 LC공진 설계 시 부하 자체를 L로 설정하여 효율을 최대화 하였다. 또한 유도가열용 인버터에 적용 가능한 스너버회로의 특성분석을 통해 본 시스템의 최적화에 관한 연구를 하였다.

• Proceedings of the KIPE Conference
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• 2015.07a
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• pp.520-521
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• 2015

본 논문은 벡터제어 기반의 IPMSM 구동 시스템에서 순시 토크 제어 시 전류제어기법에 따른 스위치의 온도특성에 관하여 기술하였다. 전류제어 기법으로는 예측전류제어기법과 기존의 PI(Proportional Integral) 제어기 기반의 SVPWM을 각각 적용하였고, 순시 토크 제어에 따른 스위치 발열량을 비교 분석하였다.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.46-51
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• 2008

In this study, evaluation system of the thermal properties of the exothermic agents was investigated. Exothermic agents property evaluation system was developed by metering variation of power supply. Thermal properties of exothermic agents was affected by material mixture condition of exothermic agents, however, it was not affected by temperature. It is possible to make various exothermic agents by means of regulating thermal properties which is based on property evaluation system of exothermic agents.

• Proceedings of the KIPE Conference
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• 2018.11a
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• pp.171-172
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• 2018

본 논문에서는 NPC (Neutral-Point-Clamped) 인버터와 ANPC (Active Neutral-Point-Clamped) 인버터의 특성과 성능을 비교 분석한다. ANPC 인버터는 기존의 NPC 인버터와 비교하여 스위칭 부하를 분산시켜 발열의 불균형을 해소하고 소자 수명을 증가시킨다. 기존의 NPC 인버터 시스템과 ANPC 인버터에 대하여 이론적인 특징과 성능을 분석하고 모델링과 시뮬레이션을 통하여 비교 분석한다.

• Magazine of RCR
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• v.15 no.4
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• pp.58-63
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• 2020

• Journal of the Korea Organic Resources Recycling Association
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• v.15 no.3
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• pp.106-112
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• 2007

The purpose of this study is to derive the mixing ratio with stable heating value to be used as fuel and secondary fuel by mixing sewage sludge cake, tar, peat moss, and verify the combustion property of produced solid fuel and the applicability of RDF as alternative fuel. Tar shows the highest heating value with 7,000kcal/kg and the heating value of sewage sludge cake and peat moss ranges from 4,000 to 4,500kcal/kg. Also, the solid fuel with length 1.6cm, diameter 1.3cm and weight 2.3g was produced using the heating value of over 6,000kcal/kg and proper mixing ratio (sewage sludge cake: tar: peat moss) from 1 : 4 : 1 to 1 : 7 : 1. Upon the analysis of the RDF applicability of produced solid fuel, the exhaust gas analysis finds that the composition concentration of exhaust gas occurred according to the mixing ratio did not change significantly and the flame lasting time was found to be around 5 minutes, similar to the lasting time of the same mass (2.3g) of general anthracite burned. Therefore, it can be concluded that solid fuel produced in this study can be used as fuel and secondary fuel.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4679-4688
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• 2011

This study was performed to the municipal waste generation amounts and characteristics for B city in Gangwon province, predicted the methane gas generation rate emitted from landfill, and analyzed the possibility of energy recovery to RDF(Refuse Derived Fuel) using combustible waste. The study results showed that the average bulk density of municipal waste for B city was 144.0 kg/$m^3$, and the average ratios of combustible waste were 36.0 % of paper, 21.6 % of vinyl, and 19.7 % of food waste. respectively. In the experiment for heating value, high and low heating value(moisture) was measured to 3,471 $kca{\ell}$/kg and 2,941 $kca{\ell}$/kg, respectively. After the prohibition of burying of food waste in landfill, the heating value of municipal waste was dramatically increased due to increase of the ratio of paper, vinyl, and plastic waste. The prediction results of methane gas generation rate emitted from landfill showed that the gas generation rate is increasing to 2,505.7 CH4 ton/year in 2021. After then, the rate is decreasing gradually. When the RDF facility is installed, the rate is decreasing after peaking at 1,956.9 CH4 ton/year in 2013. The generation rate of LFG emitted from waste landfill of B city was analyzed to 9.92 $m^3$/min, similar to 10.11 $m^3$/min for other city.

• Journal of the Korea Institute of Building Construction
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• v.14 no.5
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• pp.379-388
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• 2014

The purpose of this study is to investigate the effect of capsulated slurry phase change material (PCM) on the thermal crack in mass concrete by experimental work and FEM analysis. In this study, three conditions of samples were prepared for evaluating the level of hydration heat, i.e., a material condition, a cement paste condition and a concrete condition. Also, a compressive strength test was conducted for FEM inverse analysis. Based on the results of the experiment, exothermic function coefficients of concrete with encapsulated slurry PCM were deducted by the inverse analysis. After that, they applied to FEM analysis of the mass scale concrete structures. From the results of this experiment, $31^{\circ}C$ capsulated slurry PCM had no super cooling phenomenon in the material condition. In the cement condition, hydration heat decreased by 34.61J when PCM of 1g was mixed. In the concrete condition, PCM of 6% was deducted as the best level in hydration heat absorption. In FEM inverse analysis, rate coefficient of reaction gradually decreased when PCM mixing ratio increased. But, temperature-rise coefficient increased when PCM mixing ratio exceeded 6%. For the inversed exothermic function coefficients applying to large scale concrete structures, a thermal cracking index increased by 0.05 when PCM of 1% was mixed.