• 한국항해항만학회지
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• 제48권4호
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• pp.274-283
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• 2024

기후변화는 가장 중요한 환경 문제 중 하나로, 이 변화의 주요 원인은 화석연료 사용으로 인한 탄소배출이다. 이에 대응하기 위해 다양한 대체 연료가 주목받고 있다. 이 중에서도 수소는 대용량 저장 및 대규모 운송 등 연료로서 많은 장점을 가지고 있지만 극인화성 기체이며 빠르게 확산되는 특성이 있어 수소를 다루는 시설에서는 환기를 통해 내부 안전을 확보하는 것이 필요하다. 본 연구는 밀폐공간에서 수소가 누출될 경우, 효율적으로 배출시킬 수 있는 급·배기구의 위치를 비교 및 분석하는 것을 목적으로 한다. 실험은 총 6가지의 급기구와 배기구 조합으로 시나리오를 구성하였다. 실험과정의 안전을 고려하여 수소 대신 물리적 성질이 유사한 헬륨을 사용하여 환기시스템이 작동 중일 때의 내부 산소농도를 분석하였다. 실험결과, 6가지 시나리오 중에서 하부측면의 급기구와 상부측면의 배기구를 활용한 환기(Case2)가 4분 30초로 가장 짧은 환기소요시간을 나타내었다. 더 나아가 상·중·하부 영역에 따른 산소농도감소율을 확인한 결과, 상부 영역에서는 상부면 급기구와 상부면·상부측면에 두 개의 배기구를 활용한 환기(Case6)가, 중부와 하부에서는 Case2가 낮은 값을 보였다.

• 한국재료학회지
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• 제28권8호
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• pp.440-444
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• 2018

An effective cleaning method for Ni removal in Ni-induced lateral crystallization(Ni-MILC) poly-Si TFTs and their electrical properties are investigated. The HCN cleaning method is effective for removal of Ni on the crystallized Si surface, while the nitric acid treatment results decrease by almost two orders of magnitude in the Ni concentration due to effective removal of diffused Ni mainly in the poly-Si grain boundary regions. Using the HCN cleaning method after the nitric acid treatment, re-adsorbed Ni on the Si surfaces is effectively removed by the formation of Ni-cyanide complexions. After the cleaning process, important electrical properties are improved, e.g., the leakage current density from $9.43{\times}10^{-12}$ to $3.43{\times}10^{-12}$ A and the subthreshold swing values from 1.37 to 0.67 mV/dec.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.878-881
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• 2001

In this paper, we analyzed the characteristics of insulating material with ELB(earth leakage circuit breaker) through tracking experiment and the study was carried out three different types of samples. The tracking is breakdown phenomenon of material surface that is generated on the organic insulating material. The test method applied IEC publication 587. The result of the sample breakdown by tracking was carbonized and resistance of between the electrodes is approximately 300$\Omega$. In the result of DSC analysis, the caloric peak was detected before 100$^{\circ}C$ in product of tracking. It appeared weight loss of 10.87% at 537$^{\circ}C$ on TGA. IR spectrum analysis showed carbon-hydrogen(C-H)bond on molecular structure that is the sample of tracking.

• 공업화학
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• 제32권2호
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• pp.214-218
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• 2021

We investigated the optimal stacked structure from the perspective of process architecture (PA) through emission spectrum analysis according to the wavelength of quantum dot (QD)-organic light-emitting diodes (OLED). We confirmed that the blue-light leakage through the QD can be minimized by increasing the QD filling density above a critical value in the red QD (R-QD) layer. In addition, when the thickness of red-color filter (R-CF) at the upper part of the R-QD increased to more than 3 ㎛, the leakage of blue light through the R-CF was effectively blocked, and a very sharp emission spectrum in the red wavelength band could be obtained. According to these outstanding results, we expect that the development of QD-OLED displays with very excellent color gamut can be possibly realized.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.382-382
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• 2009

In this study, we prepared electrodes containing ionic liquid for high temperature polymer electrolyte fuel cells. Effects of ILs on electrochemical properties of the electrodes were investigated carrying out measurement of cyclic voltammograms of the various electrodes with the content of IL in a strong supporting electrolyte. As the ILs content increased in electrodes, electrochemical surface area(ESA) decreased due to the leakage of ILs from Nafion ionomer. In addition, two case of cyclic voltammograms under two simulated environment, i.e. IL leakage from Nafion ionomer in I) electrode and ii) polymer electrolyte, were investigated. As a result, IL leakage from polymer electrolyte showed worse results in electrochemical properties of the electrode.

• Korean Chemical Engineering Research
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• 제48권6호
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• pp.737-740
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• 2010

높은 누설 전류와 문턱 전압의 이동은 비정질 실리콘(a-Si:H) 트랜지스터(TFT)의 단점이다. 이러한 특성은 게이트 절연체와 활성층 박막의 막 특성, 표면 거칠기와 공정 조건에 따라 영향을 받는다. 본 연구의 목적은 누설 전류와 문턱 전압의 특성을 개선하는데 목적이 있다. 게이트 절연체의 공정 조건에 대해서는 질소를 증가한 증착 공정 조건을 적용하였고, 활성층의 공정 조건에 대해서는 산소를 증가한 공정 조건을 적용하여 전자 포획을 감소시키고 박막의 밀도를 증가시켰다. $I_{off}$는 $65^{\circ}C$ 조건하에서 1.01 pA에서 0.18pA로, ${\Delta}V_{th}$는 -1.89 V에서 -1.22V로 개선되었다.

• 한국전기전자재료학회논문지
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• 제16권12S호
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• pp.1175-1180
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• 2003

Transformer Coupled Plasma Chemical Vapor Deposited (TCP-CVD) silicon nitride (SiNx) is widely used as a gate dielectric material for thin film transistors (TFT). This paper reports the SiNx films, grown by TCP-CVD at the low temperature (30$0^{\circ}C$). Experimental investigations were carried out for the optimization o(SiNx film as a function of $N_2$/SiH$_4$ flow ratio varying ,3 to 50 keeping rf power of 200 W, This paper presents the dielectric studies of SiNx gate in terms of deposition rate, hydrogen content, etch rate and leakage current density characteristics lot the thin film transistor applications. And also, this work investigated means to decrease the leakage current of SiNx film by employing $N_2$ plasma treatment. The insulator layers were prepared by two step process; the $N_2$ plasma treatment and then PECVD SiNx deposition with SiH$_4$, $N_2$gases.

• 한국수소및신에너지학회논문집
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• 제29권4호
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• pp.307-316
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• 2018

In this study, the failure mode and effect analysis (FMEA) of hydrogen production process by using the Thermococcus onnurineus NA1 was conducted and advanced methodology to compensate the weakness of previous FMEA methodology was applied. To bring out more quantitative and precise FMEA result for bio-hydrogen production process, fuzzy logic and potential loss cost estimated from ASPEN Capital Cost Estimator (ACCE) was introduced. Consequently, risk for releasing the flammable gases via internal leakage of steam tube which to control the operating temperature of main reactor was caution status in FMEA result without applying the fuzzification and ACCE. Moreover, probability of the steam tube plugging caused by solid property like medium was still caution status. As to apply the fuzzy logic and potential loss cost estimated from ACCE, a couple of caution status was unexpectedly upgraded to high dangerous status since the potential loss cost of steam tube for main reactor and decrease in product gases are higher than expected.

• 한국세라믹학회지
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• 제42권12호
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• pp.827-832
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• 2005

In this study, thin electrolyte layer was prepared by 8YSZ ($8mol\%$ Yttria-Stabilized Zirconia) slurry dip and sol coating onto the porous anode support in order to reduce ohmic resistance. 8YSZ polymeric sol was prepared from inorganic salt of nitrate and XRF results of xerogel powder exhibited similar results $(99.2\pm1wt\%)$ compared with standard sample (TZ-8YS, Tosoh Co.). The dense and thin YSZ film with $1{\mu}m$ thickness was synthesized by coating of 0.7M YSZ sol followed by heat-treatment at $600^{\circ}C$ for 1 h. Thin film electrolyte sintered at $1400^{\circ}C$ showed no gas leakage at the differential pressure condition of 3 atm.

• 한국산업융합학회 논문집
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• 제26권3호
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• pp.499-507
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• 2023

The core of the liquefied natural gas (LNG) carrier cargo containment system (CCS) is to store and transport LNG safely under temperatures below -163 degrees Celsius. The secondary barrier of the LNG CCS is adopted to prevent LNG leakage from CCS to the ship's hull structure. Recently, as the size of the LNG CCS increases, various studies have been conducted on the applied temperature and load ranges. The present study investigates the working condition-dependent bonding strength of the PU15 adhesives of the secondary barrier. In addition, the mechanical performance is analyzed at a cryogenic temperature of -170 degrees Celsius, and the failure surface and failure mode are investigated depending on the working condition of the bonded process. Even though the RSB and FSB-based fracture mode was confirmed, the results showed that all the tested scenarios satisfied the minimum requirement of the regulation.