A Study on the Energy Demand Investigation of Gaeseong Industrial Complex

You Do-Hyun(유도현),Cho Nam-Cheol(조남철),Shin Kum-Cheol(신금철),Han Jeong-Ok(한정옥) 한국태양에너지학회 2017 한국태양에너지학회 학술대회논문집 Vol.2017 No.4

솔젤벱에 의해 제작된 $SiO_2$ 박막의 물성에 관한 연구

유도현,You Do-Hyun 대한전기학회 2004 전기학회논문지C Vol.53 No.11

SiO₂ thin films are fabricated using sol-gel method and dipping method. Gelation time is faster according to increasing the amount of H₂O except H₂O/Si(OC₂H/sub 5/)₄=4. Initial viscosity is highest at H₂O/Si(OC₂H/sub 5/)₄=6. Gelation time is faster according to increasing the amount of CH₃COOH. The relative dielectric constant of thin films decreases a little according to increasing the measuring frequency. The dielectric dissipation factor of thin films increases a little below 100kHz and it increases rapidly over 100kHz.

솔젤법에 의해 제작된 $TiO_2$ 솔과 $SiO_2$ 솔의 점도 특성에 대한 분석

유도현,You Do-Hyun 대한전기학회 2005 전기학회논문지C Vol.54 No.12

[$TiO_2$] sol and $SiO_2$ sol were prepared using sol-gel method. As $H_{2}O$/Alkoxide ratios increased, sol had cluster structure and as $H_{2}O$/Alkoxide ratios decreased, sol had linear structure. Gelation time of $TiO_2$ sol was faster than that of $SiO_2$ sol according to the time. In comparison with initial viscosity between $TiO_2$ sol and $SiO_2$ sol, $TiO_2$ sol was highest at $H_{2}O/Ti(OC_{3}H_{7})_{4}=5$, $SiO_2$ sol was almost constant according to $H_{2}O/Si(OC_{2}H_{5})_{4}$ ratios.

솔젤법에 의해 제작된 TiO₂박막 특성

유도현(Do-Hyun You) 한국진공학회(ASCT) 2001 Applied Science and Convergence Technology Vol.10 No.2

본 연구에서는 솔젤법에 의해 최적의 유전특성을 갖는 TiO2 박막의 제작조건을 정한다. 이를 위해 최적의 조건으로 합성된 sol을 이용하여 박막을 제작한 후 박막의 유전율을 측정한다. 가수분해에 필요한 물의 양이 화학 양론적인 양보다 적은 경우에는 직쇄상 구조를 갖는 투명 sol이 생성되고 많은 경우에는 cluster상 입자를 갖는 현탁 sol이 생성된다. 또한 박막의 유전율은 120℃부근을 시작으로 지수함수적으로 증가하는 것을 알 수 있다. In this study, synthesis condition of TiO2 thin films which have optimal dielectric characteristics using sol-gel method was determined. Thin films were fabricated using sol which have optimal characteristics and their permittivity was measured. In case of the amount of water for hydrolysis smaller than that for stoichiometry, sol formed clear sol which have normal chain structure. On the contrary, in case of the amount of water for hydrolysis larger than that for stoichiometry, sol formed suspended sol which have cluster structure. The permittivity of thin films increased exponentially around 120℃.

솔젤법으로 제작한 TiO₂-V₂O₅ 세라믹스의 물성

柳道鉉(Do-Hyun You) 대한전기학회 2007 전기학회논문지 Vol.56 No.7

TiO₂-V₂O? sol was prepared using sol-gel method. Sol changed to gel with hydrolysis and polymerization. DTA properties of gel powder had endothermic reaction due to evaporation of propanol about 80℃, had exothermic reaction due to combustion of propanol about 230℃ and had exothermic reaction due to combustion of alkyl group about 350℃. Crystalline properties of gel powder retained amorphous phase at 50℃, retained anatase phase from 400℃ to 600℃ and had all rutile phase over 700℃ at 0.01mole V₂O? additive. The capacitance of thin films increased with increasing heat treatment temperature and thin films had best properties at 700℃. The capacitance of thin films increased a lot with decreasing measurement frequency.

자동차 내부의 김서림 감지 및 제거를 위한 최적의 조건

유도현(Do-Hyun You) 대한전기학회 2012 전기학회논문지 Vol.61 No.5

For mist sensing, temperature-humidity sensor is attached on six positions of front glass and rearview mirror in automobile. Bottom-left side of front glass is the best position where mist is sensing. For mist removal, air conditioner is turned on intensity 1, 3 and is set the temperature at 17[℃], 25[℃]. And heater is turned on intensity 1, 3 and is set the temperature at 25[℃], 32[℃]. The best condition which mist is removed is temperature at 17[℃] and intensity 3 of air conditioner mode. At this condition, total average value of humidity output voltage difference is 0.561[V]. Also, air conditioner mode is effective than heater mode for mist sensing and removal.

R.F.스퍼터링법에 의해 제작된 TiO₂ 박막의 습도감지특성

유도현(Do-Hyun You) 대한전기학회 2013 전기학회논문지 Vol.62 No.7

TiO₂ thin films are fabricated using R.F.sputtering method. TiO₂ thin films are coated on Al₂O₃ substrate printed IDE(interdigitated electrode). Impedance of thin films decreases according to increase relative humidity and it increases according to decrease measuring frequency. When substrate temperature is room temperature, impedance of thin films is from 45.68[MHz] to 37.76[MHz] within the limits from 30[%RH] to 75[%RH] at 1[kHz]. Whereas when substrate temperature is 100[℃], impedance of thin films is from 692[kHz] to 539[kHz] within the limits from 30[%RH] to 75[%RH] at 1[kHz]. Impedance variation of thin films is bigger in low frequency regions than in high frequency regions. When substrate temperature is 100[℃], impedance of thin films is lower than that of room temperature.

$TiO_2-Nb_2O_5$ 솔의 물성에 대한 분석

유도현,You, Do-Hyun 대한전기학회 2006 전기학회논문지C Vol.55 No.7

[ $TiO_2-Nb_2O_5$ ] sol was prepared using sol-gel method. Crystalline properties of gel powder changed from rutile phase to anatase phase with increasing $Nb_2O_5$ additives at $800^{\circ}C$, while they retained rutile phase regardless of $Nb_2O_5$ additives at $900^{\circ}C,\;1,000^{\circ}C$. They retained amorphous phase from $50^{\circ}C\;to\;400^{\circ}C$, retained anatase phase from $500^{\circ}C\;to\;600^{\circ}C$ and had rutile phase over $700^{\circ}C$ at 1mole% $Nb_2O_5$ additive. After $TiO_2-Nb_2O_5$ sol retained low viscosity with normal chain structure for a long time, its viscosity increased fast with network structure. DTA properties of gel powder had endothermic reaction due to evaporation of propanol and water about $78^{\circ}C$, had exothermic reaction due to propanol combustion about $290^{\circ}C$ and had exothermic reaction due to changing of $TiO_2$ phase about $640^{\circ}C$.

3D 프린터 PLA 출력재료의 최적 출력조건

유도현(Do-Hyun You) 대한전기학회 2016 전기학회논문지 Vol.65 No.5

The purpose of this study optimizes the conditions of PLA printing material for 3D printer. Deltabot type 3D printer is used. The ranges of printing temperature, printing speed, and infill density are 195∼215℃, 10∼70mm/sec, and 10∼100% respectively. From the results of printing temperature, printing quality is almost same every printing temperature. From the results of printing speed and infill density, printing quality is excellent under 40mm/sec, and over 50% respectively. Surface roughness is 2.28 μmRa at 205℃, 10mm/sec, 100%, and is 5.93 μmRa at 205℃, 70mm/sec. Surface roughness is directly proportional to the printing speed, and is inversely proportional to the infill density. Objects fabricated PLA printing material adhere bed at room temperature.

90[wt%] SnO₂-10[wt%] TiO₂ 세라믹스의 습도감지특성

유도현(Do-Hyun You) 대한전기학회 2014 전기학회논문지 Vol.63 No.9

The purpose of this paper is to establish the optimum fabricating condition of specimens using silk screen printing, and to develop humidity sensor which has good humidity sensing properties. The specimens are fabricated under the condition of 90[wt%] SnO₂-10[wt%] TiO₂, and their microstructure, crystalline structure, humidity sensing properties are examined. From the microstructure analyses, porosity is best at 700[℃]. From the crystalline structure analyses, intensity of peak becomes strong according to increasing heat treatment temperature. From the humidity sensing properties analyses, an overall results of capacitance changes, linearity and hysteresis for the specimens is best at 600[℃] and 700[℃]. Capacitance of specimens increases according to decreasing measurement frequency, and to increasing relative humidity.