• 미생물학회지
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• 제27권4호
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• pp.323-333
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• 1989

Transposon Tn5의 단백질 합성을 E. coli 내에서 증폭 합성시키기 위하여 Bacteriophage의 Pt 촉진유전자가 Tn5의 두 개 module인 IS50L 과 IS50R을 전사시킬 수 있도록 plasmid를 재구성하였다. P1 촉진유전자로부터의 전사를 탈억제시켰을 경우, IS50R으로부터 합성되는 두 개의 단백질은 모두 그 세포내 축적량이 SDS-polyacrylamid gel에서 확인 될 정도로 증폭합성되었으나 IS501L의 두 개 단백질들은 동일 gel 상에서 확인되지 않았다. Minicell system에서 합성양상과 각 단백질들의 안정성을 조사한 결과, IS50R 단백질은 모두 안정하게 유지되었으나 IS501, 단백질은 모두 불안정하여 생분해 되어 진다는 사실을 밝혔다. 이러한 Is50L 단백질의 불안정성은 IS50L이 transposition에 있어서 불활성을 나타내는 원인이라 추정된다. 또한 IS50L고 IS50R의 단백질은 모두 동일한 open reading frame에 의하여 합성되어짐을 tryptic peptide 양상을 통하여 알 수 있었다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.888-892
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• 2014

This paper evaluates $C_{50}$ in elementary school classrooms and considers utilization of $C_{50}$ as an assessment indicator of acoustic performance. $C_{50}$ is early-to-late arriving sound ratio, recent study reported that $C_{50}$ is more appropriate as a measure of clarity and speech intelligibility than D50 because it is linearly related to subjective responses. The average of $C_{50}$ in elementary school classrooms appeared to be about +2 dB ~ +3 dB throughout 500 Hz ~ 4 kHz. However, absolute evaluation is difficult because there is no suitable reference or standard yet. As deviation of $C_{50}$ according to location is larger than reverberation time, it is expected that $C_{50}$ will be more sensitive when someone assesses acoustic performance of classrooms. Correlation between $C_{50}$ and reverberation time is very high. From logarithmic regression equation, we can estimate appropriate range of $C_{50}$ in elementary school classrooms indirectly, using standard of reverberation time in ANSI.

• 대한기계학회논문집A
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• 제24권10호
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• pp.2461-2468
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• 2000

In this paper, single fiber pull-out test is used to measure the interfacial bonding shear strength of $Ti_{50}-Ni_{50}$ shape memory alloy composite with temperature. Fiber and matrix of $Ti_{50}-Ni_{50}$ shape memory alloy composite are respectively $Ti_{50}-Ni_{50}$ shape memory alloy and epoxy resin. To strengthen the interfacial bonding shear stress, various surface treatments are used. They are the hand-sanded surface treatment, the acid etched surface treatment and the silane coupled surface treatment etc.. The interfacial bonding shear strength of surface treated shape memory alloy fiber is greater than that of surface untreated shape memory alloy fiber by from 10% to 16%. It is assured that the hand-sanded surface treatment and the acid etched surface treatment are the best way to strengthen the interfacial bonding shear strength of $Ti_{50}-Ni_{50}$ shape memory composite. The best treatment condition of surface is 10% HNO$_3$ solution in the etching method to strengthen the interfacial bonding shear strength of $Ti_{50}-Ni_{50}$ shape memory alloy composite.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.546-549
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• 2004

The T-50/A-50 Golden Eagle was developed for a supersonic trainer and light combat aircraft. At the design stage, vibration control plans were established and applied. For cockpit vibration, crew comfort vibration level was defined by the requirement of MIL-A-8892. It is found that the T-50/A-50 meets the requirement of cockpit vibration from the flight test data analysis. This paper contains the results of cockpit vibration analysis using the flight test data and the results of human vibration analysis lot the pilot inside aircraft. The human vibration level of pilot is increased as dynamic pressure is increased and at the specific high dynamic pressure, the ride comfort indicates 'a little uncomfortable'. Overall analysis results show that the vibration level of T-50/A-50 cockpit is tolerable and not critical for pilot's comfort.

• 대한기계학회논문집A
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• 제22권3호
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• pp.624-634
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• 1998

The photoelastic model material with shape memory effect and the molding processes for the material are developed in this research. The matrix and fiber of the photoelastic model material developed in this research are epoxy resin (Araldite to hardner 10 to 3 (weight ratio)) and wire of $Ti_50-Ni_50$ shape memory alloy, respectively. It is called Ti50-Ni50 Shape Memory Alloy Fiber Epoxy Composite $(Ti_50-Ni_50SMA-FEC).$ Ti50-Ni50 SMA-FEC is satisfied with the requirements of the photoelastic model material and can be used as a photoelastic model material. The maximum recovering strain of $Ti_50-Ni_50$SMA-FEC is occurred at $80^{\circ}C$ in any prestrain of $Ti_50-Ni_50$ shape memory alloy fiber and in any fiber volume ratio. Recovering strain(force) is increased with the increment of the prestrain and the fiber volume ratio. The best prestrain of $Ti_50-Ni_50$SMA-FEC is 5% for the recovering force among 1%, 3%, 5%.

• 아태비즈니스연구
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• 제12권3호
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• pp.251-269
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• 2021

Purpose & methodology - This study is to answer the following three questions, analyzing data on Top 50 Indian Billionaires, Top 50 Indian companies and Top 50 Indian start-ups. The first is whether or not traiditonal merchant caste like Vaisya's ability of creating wealth declined as some studies argue. The second is whether non-merchant caste like Brahmin, Kshatriya, OBC, Dalit, emerged as an India's new business elite. The third is whether the results of top 50 Indian companies and top 50 start-ups' analyses have similarities with that of top 50 Indian Billionaires analysis. Findings - The result is firstly, the ability of creating wealth of businessmen from the merchant caste was still overwhelming. Secondly, the big businessmen' rising from non-merchant castes as a new business elite was extremely rare. Thirdly, according to the analysis of top 50 Indian start-ups, the percentage of Vaisya has significantly declined while the the percentage of upper castes like Brahmin has noticeably increased. Fourthly, no evidence was found that businessmen from the lower castes like OBC or Dalit were increasing the expanding business influence. Research implications - The Studies mean that in big-sized Indian companies, the power of traditional merchant caste remains the same as before and is even reinforcing, while in small start-ups, Vaisya's power is considerably decreasing, and the upper castes like Brahmin who are highly educated are noticeably increasing.

• 한국컴퓨터정보학회논문지
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• 제25권11호
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• pp.9-16
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• 2020

TA-50 항공기는 공중전에 대비하여 공대공, 공대지 사격 훈련 등 다양한 상황에 대한 모의 훈련을 수행하고 있다. 또한 조종사의 실전 배치 전 훈련용으로도 사용되고 있다. 그러나 TA-50은 스마트 무장 운용 능력을 보유하고 있지 않아 훈련에 제한이 되고 있다. 이에 본 연구에서는 TA-50 항공기에 스마트 무장 중 하나인 합동정밀직격탄(JDAM)의 가상훈련이 가능하도록 구현하고자 하였다. 먼저, TA-50 항공기와 유사한 기종인 FA-50 항공기에 구현된 JDAM 기능을 분석하였다. 또한 FA-50 항공기에 구현된 기능은 소스코드의 직접 활용이 불가능하므로 머신러닝 기법(TensorFlow)을 활용하여 알고리즘을 추출하였다. 본 기능을 구현함으로써 실 무장을 장착하지 않아도 실제와 유사한 훈련이 가능할 것으로 기대된다. 마지막으로 본 연구 결과를 바탕으로 연구의 한계점을 보완하여 실제와 동일하게 구현할 수 있는 방안을 제안하고자 한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1384-1387
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• 2003

Pressurization test is usually required in aircraft full-scale static test. There are several test conditions including pressurization of cockpit, fuselage fuel tank, air inlet duct for T-50 full-scale static test. In this paper, the test conditions, equipment, piping analysis for the pressurization test are introduced. Tank simulation test is performed to verify the validity of piping analysis and to find good tuning parameters for the pressurization channel in the servo controller. Several test setup for pressurization of T-50 test is introduced. Test article volume is filled by form, $60%{\sim}80%$ volume is reduced for the T-50 full-scale static test. Pressurization system is connected to servo controller which also controls hydraulic actuator. Load and pressure control is synchronized by using the same servo controller during T-50 test. Typical control result for pressurization test condition is shown. Pressurization tests of T-50 full-scale static test was completed successfully.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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• pp.476-480
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• 2003

Polyethylene used as insulating material of power cable is nonpolar and low dielectric loss polymer. But it has defects of tree generation and accumulation of space charge by an applied voltage resulting in the decreased life and performance. To solve these problems, mixed films with LLDPE and EVA that is similar to LLDPE at physical properties in case of low VA contents were made and tested due to the blend ratios of 80:20, 70:30, 60:40 and 50:50[wt%] respectively. We investigated AC electrical treeing characteristics to acquire the best mixture ratio and effect of the tip radius of needle electrode to develop excellent treeproof materials. The degree of crystallity calculated with XRD pattern is higher for pure LLDPE, 50:50 and 70:30. For DSC analysis, it is confirmed that the melting points of mixed specimens are lower than that of pure LLDPE and higher than pure EVA's. The shape of tree propagation showed that pure EVA was electrical tree shape of the branch type, pure LLDPE and blended specimens was able to confirm tree shape of the bush type. As the tip radius go up in the blend ratio 70:30 specimen, the tree inception voltage rise. Probably the reason is the relaxation of electric field in the specimen with bigger tip ratio. As the 6 specimens were applied AC 5[KV],7.5[KV],10[KV] respectively, tree growth length is far shorter in the specimen with blend ratio 70:30, 50:50 than in pure EVA and pure LLDPE specimen. Conclusively, it is confirmed that specimens of which blend ratio are 70:30 and 50:50 are good in electrical tree retardant characteristics, especially, 70:30 has lower dielectric loss than 50:50 and its mixture ratio is the best.

• 정보관리학회지
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• 제14권1호
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• pp.183-206
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• 1997

본 연구는 정보검색용 표준 프로토콜인 Z39.50을 공동편목에 응용하기 위하여 Z39.50의 발전과정과 제반기능에 대하여 살펴보고, Z39.50의 속성과 데이터베이스 갱신서비스를 토대로 Z39.50 공동편목 게이트웨이 모형을 설계하였다. 이 게이트웨이는 국내교육.연구도서관 서지협력망의 온라인 공동편목시스템을 대상으로 하였다. 본 연구에서 설계된 두가지 측면의 Z39.50공동편목 게이트웨이, 즉 중앙집중형 공동편목 게이트웨이와 분산형 공동편목 게이트웨이 모형은 기본적으로 웹서버에서 동작하며 이용자 접근이 쉬운 웹브라우저를 통하여 접근할 수 있도록 설계하였다.