• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1761-1763
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• 1998

ITO(Iridium-Tin Oxide) thin film, as discharge electrodes in AC PDP, should have low resistivity and high transparency. Regarded as a high deposition rate method, the ITO thin film fabricated by the facing target sputtering system has been studied in this paper. The electrical property of the ITO film deposited below $150^{\circ}C$ is not satisfied. The SEM pictures show that the ITO films deposited below $150^{\circ}C$ are amorphous. After being annealed the amorphous ITO films become crystalline, and for this reason, the electrical property of amorphous ITO films can be effectively improved by annealing process. An ITO film with the resistivity as low as $1.99{\times}10^{-4}$ and transparency above 85% has be gotten after vacuum annealing at $300^{\circ}C$ for 2 hours while deposited at $75^{\circ}C$. The corresponding deposition rate is $220{\AA}/min$.

• 한국추진공학회지
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• 제10권3호
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• pp.109-117
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• 2006

인공위성 및 발사체의 자세제어용으로 사용되는 단일추진제 추력기용 하이드라진의 분해촉매에 대한 연소성능을 실제 지상연소시험을 통하여 검증하였다. 촉매연소성능을 확인하기 위한 촉매 시험장치를 (주)한화와 공동으로 설계/제작하였으며, 이를 통하여 하이드라진 분해촉매의 촉매 연소특성을 시험하였다. 연소지연시간, 촉매활성도, 촉매안정도를 2회에 걸쳐 측정한 결과 각각 평균 25msec, 2%, $704^{\circ}C$으로 만족할 만한 결과를 얻었다. 또한 현재 진행 중인 국산화 촉매 시제품의 개발현황과 분해성능 시험 결과를 설명하였다.

• Nuclear Engineering and Technology
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• 제45권5호
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• pp.695-700
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• 2013

Thirty-eight radiation safety reports for brachytherapy equipment were evaluated to determine the current status of brachytherapy units in Korea and to assess how radiation oncology departments in Korea complete radiation safety reports. The following data was collected: radiation safety report publication year, brachytherapy unit manufacturer, type and activity of the source that was used, affiliation of the drafter, exposure rate constant, the treatment time used to calculate workload and the HVL values used to calculate shielding design goal values. A significant number of the reports (47.4%) included the personal information of the drafter. The treatment time estimates varied widely from 12 to 2,400 min/week. There was acceptable variation in the exposure rate constant values (ranging between 0.469 and 0.592 ($R{\cdot}m^2/Ci{\cdot}hr$), as well as in the HVLs of concrete, steel and lead for Iridium-192 sources that were used to calculate shielding design goal values. There is a need for standard guidelines for completing radiation safety reports that realistically reflect the current clinical situation of radiation oncology departments in Korea. The present study may be useful for formulating these guidelines.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.183-188
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• 2012

A blue phosphorescent $Ir(dfpypy)_3$ (dfpypy:fluorinated pyridine-pyridine ligand) complex with meridional configuration has been synthesized by newly developed effective method and its solid state structure and photoluminescence are characterized. For this complex, mer-$Ir(dfpypy)_3$, the glass-transition and decomposition temperatures appear at $160^{\circ}C$ and $384^{\circ}C$ respectively in TGA and DSC experiments, which indicates that this complex has high thermal stability. In a crystalline structure, an average Ir-C bond length of mer-$Ir(dfpypy)_3$ is slightly longer than that of fac-$Ir(dfpypy)_3$, which assumed to be due to the weak trans-influence. The absorption and emission spectra are observed more red-shifted in mer-$Ir(dfpypy)_3$ than fac-$Ir(dfpypy)_3$. In addition, the former is readily oxidized than the latter in electrochemical behavior.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2009년도 한국우주과학회보 제18권2호
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• pp.40.3-41
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• 2009

인류가 위성을 발사하기 시작하면서 수많은 우주파편이 발생하게 되었고 이로 인하여 우주파편 환경은 날이 갈수록 심각해지고 있다. 우주공간을 비행하는 우주물체는 분쇄된 파편, 임무 관련 파편, rocket body 그리고 운용위성으로 구분된다. U.S. Space Surveillance Network에 따르면 10cm 이상 크기를 갖는 물체는 현재 13,000개가 넘는다고 알려지고 있고 질량만 해도 6,000톤이 넘는다. 이런 우주파편 환경으로 인하여 우주파편 간의 충돌, 우주파편과 운용위성 간의 충돌 또는 운용위성 간의 충돌에 대한 우려가 꾸준히 제기되어왔고, 불행하게도 2009년 2월 10일 Iridium 33과 Cosmos 2251 위성이 고도 790km 부근에서 충돌하여 1,300여개의 우주파편이 발생했다. 또한 2007년에 중국이 고도 860km 부근에서 750kg에 해당하는 자국의 위성(FY-1C)을 미사일로 격추시킴에 따라 2500여개의 우주파편이 발생하여 저궤도의 우주파편 환경을 더욱 심각하게 만들고 있다. 운용위성과 우주파편과의 충돌 가능성을 분석하기 위해서는 우주파편 및 위성의 궤도정보를 알아야 한다. 이를 위해서 NORAD(North American Aerospace Defense Command)에서 제공하는 TLE(Two Line Element)가 주로 이용된다. 하지만 관측 및 궤도 결정 특성상 수 km의 오차를 포함하므로 궤도정보의 공분산이 크다는 단점이 있으므로 충돌 분석을 수행하는데 있어 한계가 있다. 이 논문은 충돌분석 수행에 있어 TLE 정보만을 이용한 경우뿐만 아니라 정밀궤도와 TLE를 동시에 이용한 경우를 비교함으로써 충돌 불확실성의 해소방안을 제시할 계획이다.

• 한국응용과학기술학회지
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• 제18권3호
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• pp.186-190
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• 2001

By fabricating the organic light-emitting devices (OLEDs) based on phosphorescent material, the internal quantum efficiency can reach 100%, compared to 25% in the case of the fluorescent material. Thus, the phosphorescent OLEDs have recently been extensively studied and showed higher internal quantum efficiencies then the conventional OLEDs. In this study, we investigated the characteristics of the phosphorescent OLEDs, with the green emitting phosphor, $Ir(ppy)_{3}$, (tris(2-phenylpyridine)iridium). The devices with a structure of $ITO/TPD/Ir(ppy)_{3}$ doped in the host material $/BCP/Alq_{3}/Li:Al/Al$ were fabricated, and its electrical and optical characteristics were studied. By changing the doping concentration of $Ir(ppy)_{3}$, we fabricated several devices and investigated the device characteristics. OLEDs doped into BCP by 10% showed the best characteristics. For 10% doped OLEDs, the maximum luminance of was over 10000 $cd/m^{2}$, and the maximum power efficiency was 7.14 lm/W.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.486-488
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• 2009

High efficiency deep blue and pure white phosphorescent organic light emitting diodes were developed using a new deep blue phosphorescent dopant, tris((3,5-difluoro-4-cyanophenyl)pyridine) iridium (FCNIr). A high quantum efficiency of 9.1 % with a color coordinate of (0.15, 0.16) at 1,000 cd/$m^2$ was obtained in the deep blue device and a high quantum efficiency of 15.2 % with a color coordinate (0.30, 0.32) was obtained in the pure white organic light-emitting diodes. The quantum efficiency of the pure white device is the best quantum efficiency value reported in the pure white device up to now.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1511-1514
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• 2009

Organic light emitting layer in OLED device was formed by gravure printing process in this work. Organic surface coated by gravure printing typically showed relatively bad uniformity. Thickness and roughness control was characterized by applying various mixed solvents in this work. Poly (N-vinyl carbazole) (PVK) and fact-tris(2-phenylpyridine)iridium($Ir(ppy)_3$) are host dopant system materials. PVK was used as a host and Ir(ppy)3 as green-emitting dopant. To luminance efficiency of the plasma treatment on etched ITO glass and then PEDOT:PSS spin coated. The device layer structure of OLED devices is as follow Glass/ITO/PEDOT:PSS/PVK+Ir(ppy)3-Active layer /LiF/Al. It was printed by gravure printing technology for polymer light emitting diode (PLED). To control the thickness multi-printing technique was applied. As the number of the printing was increased the thickness enhancement was increased. To control the roughness of organic layer film, thermal annealing process was applied. The annealing temperature was varied from room temperature, $40^{\circ}C$, $80^{\circ}C$, to $120^{\circ}C$.

• 한국수소및신에너지학회논문집
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• 제27권5호
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• pp.471-477
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• 2016

In this research, the Ir supported $TiO_2$ (P25) catalyst was prepared by precipitation method for oxygen evolution reaction. The $Ir/TiO_2$ catalyst was synthesised by reduction reaction using reducing agent. Physiochemical characterizations of synthesized $Ir/TiO_2$ catalyst was studied by means of SEM, EDS mapping, TEM and XRD. The Electrochemical characterizations were tested by using the technique of CV and LSV by RDE and Potentiostat. Physicochemical properties were characterized with XRD where Iridium metal morphology and Ir(111) and Ir(222) peaks were founded. $Ir0.2Ru0.8O_2$ exhibited higher OER activity than $Ir0.5Ru0.5O_2$ followed by $Ir/TiO_2$ and $IrO_2$.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 춘계학술대회
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• pp.828-829
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• 2010

초경합금 성형용 코어를 이용한 고온 압축 성형방식으로 제작되기 때문에 성형용 코어의 초정밀 연산 가공 및 코어면 코팅 기술 개발이 시급한 상황이다. 따라서 본 연구에서는 성형용 초경합금 코어의 연삭가공을 수행하고, 가공 완료된 성형용 코어의 가공면에 Re-Ir 코팅을 수해, 측정을 통하여 코팅면이 표면 조도에 미치는 영향에 대하여 연구를 수행하였다.