• Annual Conference of KIPS
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• 한국정보처리학회 2001년도 춘계학술발표논문집 (하)
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• pp.997-1000
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• 2001

컴퓨터와 인터넷 사용의 대중화 시대가 열리면서 소프트웨어의 구조도 점차 복잡해짐은 물론 크기도 방대해지고 있으나 S/W 개발 기술 발전 속도는 매우 더디어 소프트웨어 개발과 유지보수 비용의 증가로 인해 소프트웨어 위기 문제가 발생하게 되었다. 이에 대한 대안으로 소프트웨어 생산성, 품질, 효율성을 높이기 위해서 부품화와 조립의 특성을 지닌 컴포넌트 기반 개발 방법이 제시되었다. 컴포넌트 명세에 있어 기존에 이미 많은 명세 언어가 사용되고 있으며, 이들은 나름대로의 장점을 가지고 있으나, 이들은 대부분 구현에 있어 특정 언어에 의존성이 강하며, 표현 능력에 한계를 가지고 있다. 이러한 한계를 해결하기 위해 문제 요구사항에 대한 설명, 컴포넌트의 기능, 그리고 컴포넌트 구조에 대한 명확한 정의를 제공하는 정형화된 명세 언어에 대한 연구가 현재 이루어지고 있으나, 대부분이 컴포넌트 명세 기법에 대한 표준이 없고, 명세서에 대한 데이터 모델링 방법 및 표현언어에 대한 기준이 없이 컴포넌트의 구문적 측면만을 고려한 개발을 하고 있는 실정이다. 본 논문에서는 컴포넌트 명세서를 규격화하고 규격화된 명세서를 표준 메타 언어인 XML 기반으로 모델링 하고자 한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• 제6권6호
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• pp.931-936
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• 2002

By emphasize and enhance security in encryption of same viewdata in this research, constructed video conference system that apply real time video encryption techniques that confidentiality and integrity aspect are emphasized than video conference system that depend on existent user certification techniques. Sender's image transmits Vernam's encryption process to listener by packet. Listener can display image through image's decipher process and uncompress after unite receiving transmited image. This time, solved transmission speed delay problem by video's real time encryption using Vernam's algorithm that encryption and the decipher speed are fast. Simplification problem of Vernam algorithm wished to solve Session Key that use security Key that is used encipherment and decipher in channel between Client and Server using RSA algorithm.

• Proceedings of the KSME Conference
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• 대한기계학회 2003년도 추계학술대회
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• pp.1145-1150
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• 2003

Zr-based bulk metallic glasses have a significant mechanical properties such as high strength and elastic strain limit, and a good processing ability due to the deformation behavior such as superplasticity under supercooled liquid region. Recently, many researches on the determination of optimum working condition in various bulk metallic glasses have been carried out. In this study, the deformation behavior and forming conditions of $Zr_{55}Cu_{30}Al_{10}Ni_{5}$ bulk metallic glass were investigated under three different strain rates and at various temperatures between 627K and 727K. The glass transition temperature, crystallization temperature and supercooled liquid region of $Zr_{55}Cu_{30}Al_{10}Ni_{5}$ bulk metallic glass are 680K, 762K and 82K, respectively.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 한국감성과학회 2001년도 추계학술대회 논문집
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• pp.245-250
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• 2001

화장품 사용 시 소비자가 가장 중요하게 느끼는 요인은 효과와 촉감이라고 볼 수 있다. 특히 반복적인 사용을 위해서 쾌적한 촉감은 필수 조건이다. 그런데, 촉감은 사용하는 사람 자신의 감각에 의존하는 것이므로, 이러한 화장품의 촉감을 포함하는 성능을 평가하기 위해서 사람에 의한 최종평가는 필수적인 단계이다. 따라서, 여러 특성의 강도를 측정하는 분석형 관능평가와 소비자의 선호도를 조사하는 기호형 관능평가의 필요성이 요구되며, 두 결과를 종합적으로 고려하는 것이 바람직할 것이다. 우리는 훈련된 전문패널에 의해 다양한 자외선차단 크림과 로션들에 대한 분석형 관능평가를 실시하였다. 그 결과, 자외선차단 제품의 관능속성 평가의 주요인은 잔여감 요인과 발림성 요인으로 나타났으며, 이 결과에 따라 제품들을 2차원 공간 상에 위치하였다. 이 중 몇 제품을 선택하여 20대 후반 여성소비자를 대상으로 기호형 관능평가를 실시하였다. 평상시 실제 화장단계에서 인지되는 자외선차단제품에 대한 용어들은 촉촉함 및 도포균일성 요인/흡수속도 요인의 두가지 요인으로 분류되었다. 이상적인 자외선차단제품의 사용감은 너무 촉촉하지도 매트하지도 않으면서, 흡수속도는 빠르고 화장밀림이나 번들거림이 적은 사용감을 나타내는 특성쪽으로 나타났다.

• Journal of Digital Policy
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• 제1권2호
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• pp.47-52
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• 2022

The absolute dependence on GPS signals for positioning, unstable flight, and short flight time due to battery limitations are the major problems to extend the practical use of drones in the industry. In particular, the short flight time of about 20 minutes is a big issue to the use of drones, and to overcome this, the liquid hydrogen powered drone is being actively developed. However, the revision of the current regulation and certification system for liquid hydrogen powered drone has not been completed yet, making it difficult to test, certify, and commercialize the hydrogen powered drone, which eventually becomes a problem in pre-occupying the increasing drone market. In this paper, we analyze the development trends of hydrogen powered drone and provide the current issues on regulations and certification systems for hydrogen powered drone.

• Journal of the Institute of Electronics Engineers of Korea TC
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• 제38권7호
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• pp.1-5
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• 2001

This study accomplish comparison and analysis multimedia access network speed configuration which is effected by different environmental variation. For this testing. Not only LAN configuration which is symmetric network, But also the ADSL which is asymmetric network is tested by network speed checking software which is designed by our lab in a 10BaseT environment. In the case of TCP receive speed, we find out the network speed is changed according to bands of network to 90% of CPU load. Also, If the TCP receive windows's size became 2 times rate more than MTU, it reduced the relation of speed rate.

• Journal of the Korean Institute of Gas
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• 제17권1호
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• pp.13-18
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• 2013

Experimental studies were carried out to investigate the interactions between the propagating flame fronts and different multiple obstacles within an explosion chamber. The explosion chamber is 600 mm in height, $700{\times}700mm^2$ in cross-section and has a H/L value of 0.86. Three different multiple obstacles with the blockage ratio of 0.43 were replaced within the chamber. The results showed that relatively higher local flame displacement speed was observed with the triangular obstacle while the lower was observed with the circular one. It was found that the local flame displacement speeds behind the obstacle were largely dependent on the obstacle types. It was also found that as the flame interacted with the flow field generated behind the obstacle, the probability density functions(PDFs) of the local flame displacement speed were extensively distributed toward higher speeds.

• KSBB Journal
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• 제10권3호
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• pp.323-334
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• 1995

The effects of glucose on cell growth kinetics, monoclonal antibody productivity, and cell metabolism or hybridoma cells were investigated. The mouse-mouse hybridoma cell line VIII H-8 producing mouse IgG2a was used as a modal system. Glucose showed substrate inhibition type dependence on specific growth raie. The maximum cell density increased as initial glucose concentration increased up to 4 g/$\ell$. Glucose showed a strong influence on cell death kinetics, and an inverse relationship between specific death rate and glucose concentration was found. Cell viability and monoclonal antibody production increased as initial glucose concentration increased. The specific glucose consumption rate increased with glucose concentration, and cumulative specific lactate production rate increased with increasing initial glucose concentration. The overall kinetics of ammonium ion production was almost invariant with respect to initial glucose concentration, while the cumulative specific ammonium ion production rate was dependent on initial glucose concentration.

• Journal of the Korean Vacuum Society
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• 제7권2호
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• pp.161-168
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• 1998

Reactive ion etching process for InGaAs/InP using the CH4/H2 high density inductively coupled plasma was investigated. The experimental design method proposed by Taguchi was utilized to cover the whole parameter range while maintaining reasonable number of actual experiments. Results showed that the ICP power mainly affects surface roughness and verticality of the sidewall, bias power does etch rate and verticality, CH4 gas concentraion does the verticality and etch rate, and the distance between the induction coil and specimen mostly affects the surface roughness. It was also observed that the chamber pressure is the dominant parameter for the etch rate and verticality of the sidewall. The optimum condition was ICP power 700W, bias power 150 W, 15% $CH_4$, 7.5 mTorr, and 14 cm distance, resulting in about 3 $\mu\textrm{m}$/hr etch rate with smooth surfaces and vertical mesa sidewalls.

• Journal of Soil and Groundwater Environment
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• 제11권2호
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• pp.22-37
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• 2006

The applicability of biobarrier or in situ microbial filter technology for the remediation of groundwater contaminated with chlorinated solvent was investigated through batch microcosm study. The efficiency and rates of reductive dechlorination of tetrachloroethylene (PCE) are known to be highly dependent on hydrogen concentration. In this study, the effect of electron donors on the reductive dechlorination of PCE was investigated using vermicompost (or worm casting) and peat as a biobarrier medium. The effect of organic acids (lactate, butyrate and benzoate), yeast extract and vitamin $B_{12}$ on the reductive dechlorination was investigated. In the absence of biobarrier medium (adsorbent), addition of electron donors stimulated the dechlorination rate of PCE compared to the control experiment (i.e., no electron donor added). Among the treatments, addition of lactate or lactate/benzoate as hydrogen donor exhibited the highest dechlorination rate ($k_1=0.0260{\sim}0.0266\;day^{-1}$). In case of using vermicompost as a biobarrier medium, amendment of lactate/benzoate exhibited the highest dechlorination rate following with a pseudo-first-order degradation rate constant of $k_1=0.0849\;day^{-1}$. In contrast, when Pahokee peat was used as a biobarrier medium, either butyrate or lactate addition exhibited the highest dechlorination rate with $k_1$ values of 0.1092 and $0.1067\;day^{-1}$, respectively. The results of this study showed the potential applicability of in situ biobarrier technology using vermicompost or peat as a barrier material for the remediation of groundwater contaminated with chlorinated solvent.