• 복식
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• 제51권2호
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• pp.193-203
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• 2001

The hip-length jacket(유) worn by the Korean from the ancient times is tole prototype of the contemporary jacket. Hip-length jacket was transferred to Japan and worn by all the people beyond the class. From 12C, the King and the high class people wore the clothing influenced by Tang(唐) country but the common people continuously wore the hip-length jacket. Currently the hip-length jacket is worn by the merchant and is used as the clothing of the celebration. The hip-length jacket has not been much changed in terms of the form.

• Current Photovoltaic Research
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• 제2권2호
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• pp.59-62
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• 2014

Minority carrier diffusion length is one of the most important parameters of solar cells, especially for short circuit current density (Jsc). In this report, we proposed the calculating method of the minority carrier diffusion length ($L_n$) in CIGS solar cells through biased quantum efficiency (QE). To verify this method's reliability, we chose two CIGS samples which have different grain size and calculated $L_n$ for each sample. First of all, we calculated out that $L_n$ was 56nm and 97nm for small and large grain sized-cell through this method, respectively. Second, we found out the large grain sized-cell has about 7 times lower defect density than the small grain sized-cell using drive level capacitance profiling (DLCP) method. Consequently, we confirmed that $L_n$ was mainly affected by the micro-structure and defect density of CIGS layer, and could explain the cause of Jsc difference between two samples having same band gap.

• 한국환경보건학회지
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• 제35권6호
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• pp.500-509
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• 2009

Passive samplers have been used for many years for the sampling of organic vapors in work environment atmospheres. Currently, all passive samplers used in domestic occupational monitoring are foreign products. This study was performed to evaluate variable parameters for the development of passive organic samplers, which include the geometry of the device and diffusive length for the sampler design. Four prototype diffusive lengths; A-1(4.5 mm), A-2(7.0 mm), A-3(9.5 mm), A-4(12.0 mm) were tested for adsorption performances to a chemical mixture (benzene, toluene, trichloroethylene, and n-hexane) according to the US-OSHA's evaluation protocol. A dynamic vapor exposure chamber developed and verified by related research was used for this study. The results of study are as follows. The results in terms of sampling rate and recommended sampling time test indicate that the most suitable model was A-3 (9.5 mm diffusive lengths on both sides) for passive sampler design in time weighted average (TWA) assessment. Sampling rates of this A-3 model were 45.8, 41.5, 41.4, and 40.3 ml/min for benzene, toluene, trichloroethylene, and n-hexane, respectively. The A-3 models were tested on reverse diffusion and conditions of low humidity air (35% RH) and low concentrations (0.2 times of TLV). These conditions had no affect on the diffusion capacity of samplers. In conclusion, the most suitable design parameters of passive sampler are: 1) Geometry and structure - 25 mm diameter and 490 $mm^2$ cross sectional area of diffusion face with cylindrical form of two-sided opposite diffusion direction; 2) Diffusive length - 9.5 mm in both faces; 3) Amount of adsorbent - 300 mg of coconut shell charcoal; 4) Wind screen - using nylon net filters (11 ${\mu}m$ pore size).

• 전자공학회논문지
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• 제51권3호
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• pp.177-184
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• 2014

화학기상증착의 텅스텐 실리사이드 듀얼 폴리 게이트 구조에서 플로린이 게이트 산화막에 미치는 영향을 전기적 물리적 측정 방법을 사용하여 연구하였다. 플로린을 많이 함유한 텅스텐 실리사이드 NMOS 트랜지스터에서 채널길이가 감소함에 따라 게이트 산화막 두께는 감소하여 트랜지스터의 롤업(roll-off) 특성이 심화된다. 이는 게이트 재 산화막 열처리 공정에 의해 수직방향으로의 플로린 확산과 더불어 수평방향인 게이트 측면 산화막으로의 플로린 확산에 기인한다. 채널길이가 짧아질수록 플로린의 측면방향 확산거리가 작아져 수평방향 플로린 확산이 증가하고 그 결과 게이트 산화막의 두께는 감소하게 된다. 반면에 PMOS 트랜지스터에서는 P형 폴리를 만들기 위한 높은 농도의 붕소가 플로린의 게이트 산화막으로의 확산을 억제하여 채널길이에 따른 산화막 두께 변화 특성이 보이지 않는다.

• 대한약리학회지
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• 제29권1호
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• pp.157-163
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• 1993

n-Alkanols의 분자적 약리작용기전 탐구에 기초자료를 제공하기 위하여 소의 신선한 대뇌피질로부터 분리한 synaptosomal plasma membrane vesicles (SPMV) 지질 이중층의 측방확산운동에 미치는 n-alkanols의 영향을 형광 probe법으로 검색하였다. n-Alkanols는 SPMV 지질 이중층의 측방확산운동 범위와 속도를 농도 의존적으로 증가시켰고 1-nonanol까지는 탄소수가 두개 증가될 때마다 그 효력은 약 10배 가량 증가되었으나 탄소수 10개인 1-decanol의 효력은 오히려 감소되는 경향을 나타내었다.

• 한국결정성장학회지
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• 제9권3호
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• pp.334-338
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• 1999

p형 단결정 규소 웨이퍼를 불화수소 용액속에서 전류밀도와 양극반응 시간을 변화시켜 다공질규소를 제작하고, 그 질량을 측정한 후 이 값으로부터 다공도와 쪽거리(fractal) 차원을 계산하였다. 그 결과 양극반응 시간이 일정한 경우 다공도는 전류밀도에 비례하였다. 그리고 전류밀도가 일정한 경우 여러 양극반응 시간의 데이터로부터 얻은 쪽거리 차원은 일정하였다. 또한 쪽거리 차원은 불화수소의 농도 증가에 따라 감소하였다. 이같은 실험결과를 퍼짐한계침전(diffusion limited depostion) 모형으로 계산된 2차원 컴퓨터 시늉내기(simulation) 결과와 비교 분석하였다. 시늉내기 결과 다공도는 퍼짐거리에 비례하였으며, 쪽거리 차원은 퍼짐거리와 반비례하였다. 이때 퍼짐거리는 전류밀도에 비례하고 불화수소의 농도에 반비례하는 물리량이므로 정성적으로 실험결과와 일치하였다. 그러나 쪽거리 차원이 증가함에 따라 다공도가 감소되는 결과는 실험결과와 상반되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.553-556
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• 1999

This paper presents a proper condition to achieve above 19 % conversion efficiency using PC1D simulator. Cast poly-Si wafers with resistivity of 1 $\Omega$-cm and thickness of 250 ${\mu}{\textrm}{m}$ were used as a starting material. Various efficiency influencing parameters such as rear surface recombination velocity and minority carrier diffusion length in the base region, front surface recombination velocity, junction depth and doping concentration in the Emitter layer, BSF thickness and doping concentration were investigated. Optimized cell parameters were given as rear surface recombination of 1000 cm/s, minority carrier diffusion length in the base region 200 ${\mu}{\textrm}{m}$, front surface recombination velocity 100 cnt/s, sheet resistivity of emitter layer 100 $\Omega$/$\square$, BSF thickness 5 ${\mu}{\textrm}{m}$, doping concentration 5$\times$10$^{19}$ cm$^3$ . Among the investigated variables, we learn that a diffusion length of base layer acts as a key factor to achieve conversion efficiency higher than 19 %. Further details of simulation parameters and their effects to cell characteristics are discussed in this paper.

• Bulletin of the Korean Chemical Society
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• 제12권6호
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• pp.625-628
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• 1991

Using uniform flat plate-like samples of ZSM-5 zeolites, diffusion coefficients were measured volumetrically for the diffusion of xylene, ethyltoluene and diethylbenzene by direct measurement of sorption rate. Toluene disproportionation over H(100)-, K(72)-and Cs(82)-ZSM-5 at 773 K and toluene methylation, toluene ethylation and ethylbenzene ethylation over Cs(75)-ZSM-5 at 623 K were carried out. The selective formation of para xylene during the toluene disproportionation, presumably due to the increased tortuosity over Cs-ZSM-5, could be explained by smaller diffusion coefficient in Cs-ZSM-5 than in K-and H-ZSM-5. The para selectivity increased in the order; toluene methylation < toluene ethylation < ethylbenzene ethylation. As the chain length of the alkyl substituent in dialkylbenzenes is increased, the para selectivity of the products was improved. It may be attributed to the differences in the ratios of diffusion coefficient of para products to that of ortho ones. Diffusion coefficient of m-xylene was about 1 order of magnitude smaller than that of o-xylene.

• 대한기계학회논문집B
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• 제33권4호
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• pp.264-271
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• 2009

Characteristics of a counter flowing diffusion flame, which is formulated by an oppositely-injected methane-jet flow in a narrow channel of a uniform air flow. The location of the flame fronts and the flame lengths were compared by changing the flow rates of fuel. To distinguish the effects of the narrow channel on the diffusion flame, a numerical simulation for an ideal two-dimensional flame was conducted. Overall trends of the flame behavior were similar in both numerical and experimental results. With the increase of the ratio of jet velocity to air velocity flame front moved farther upstream. It is thought that the flow re-direction in the channel suppresses fuel momentum more significantly due to the higher temperature and increased viscosity of burned gas. Actual flames in a narrow channel suffer heat loss to the ambient and it has finite length of diffusion flame in contrast to the numerical results of infinite flame length. Thus a convective heat loss was additionally employed in numerical simulation and closer results were obtained. These results can be used as basic data in development of a small combustor of a nonpremixed flame.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.133-134
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• 2006

A simple doping method to fabricate a very thin channel body of the n-type fin field-effect-transistor (FinFET) with a 20 nm gate length by solid-phase-diffusion (SPD) process is presented. Using As-doped spin-on-glass as a diffusion source of arsenic and the rapid thermal annealing, the n-type source-drain extensions with a three-dimensional structure of the FinFET devices were doped. The junction properties of arsenic doped regions were investigated by using the $n^+$-p junction diodes which showed excellent electrical characteristics. Single channel and multi-channel n-type FinFET devices with a gate length of 20-100 nm was fabricated by As-SPD and revealed superior device scalability.