• Korean Journal of Food Science and Technology
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• v.49 no.6
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• pp.610-616
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• 2017

${\gamma}$-Glutamyltranspeptidase (GGT, EC 2.3.2.2) transfers ${\gamma}$-glutamyl moiety from glutamine to amino acids or peptides and hydrolyzes glutamine to glutamate and ammonia. In order to overproduce ${\gamma}$-glutamyltranspeptidase from Bacillus amyloliquefaciens (BAGGT), the encoding gene was cloned and expressed in Bacillus subtilis. The productivity of BAGGT in Bacillus subtilis was improved by 42-fold by using a dual-promoter system that was generated by combining promoters from B. subtilis ${\alpha}$-amylase and BAGGT genes. Through optimization of medium composition by Plackett-Burman design and central composition design, BAGGT was produced at $18.3{\times}10^7U/L$ of culture in the optimized medium. Compared to previously used Luria-Bertani medium, the optimized culture medium (15 g/L molasses, 60 g/L corn steep liquor, 6 g/L yeast extract, 4 g/L NaCl, 6 g/L $K_2HPO_4$, and 2 g/L $KH_2PO_4$), resulted in a 4.3-fold increase in production of BAGGT.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.12
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• pp.1087-1092
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• 2010

A micro 3D-PTV system has been constructed using a single camera system. Two viewing holes were created behind the object lens of the microscopic system to construct a stereoscopic viewing image. A hybrid recursive PTV algorithm was used. A concept of epipolar line was adopted to eliminate many spurious candidates. Three-dimensional velocity vector fields were obtained by calculating the three-dimensional displacements of particles that were identified as being identical. The system consists of a laser light source (Ar-ion, 500 mW), one high-definition camera ($1028{\times}1024$ pixels, 500 fps), a circular plate with two viewing holes, and a host computer. The performance of the developed algorithm was tested using artificial images. The characteristic of the vector recovery ratio was investigated for the particle numbers. A micro backward-facing step channel ($H{\times}h{\times}W:\;36{\mu}m{\times}70{\mu}m{\times}3000{\mu}m$) was measured using the developed measurement system. The results were in good qualitative agreement with other results.

• Electronics and Telecommunications Trends
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• v.32 no.4
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• pp.57-66
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• 2017

지능 정보 사회의 도래와 함께 클라우드 컴퓨팅은 정보통신기술 전반을 융합하는 주축으로 자리 잡았다. 다양한 클라우드 컴퓨팅 인프라가 새롭게 구축되고 있으며, 새로운 클라우드 서비스들도 끊임없이 쏟아져 나오고 있다. 그러나, 클라우드 환경과 서비스가 다양해질수록, 운용에 대한 복잡성 또한 증가한다. 클라우드 서비스 브로커리지(CSB: Cloud service brokerage) 플랫폼은 사용자에게 다양한 클라우드 서비스에 대한 검색, 배치, 사용 및 관리 환경을 제공하여 통합된 멀티 클라우드의 접점을 제공하는 시스템으로, 복잡한 이종 환경의 서비스에 대하여 단순하고 일관된 사용 환경을 제공함으로써 서비스 생태계를 활성화하는 기술이다. 본고에서는 CSB 플랫폼의 개념과 기술 구조를 설명하고, 기술 동향과 더불어 국내외 표준화 동향에 대해 살펴본다.

• 시스템엔지니어링워크숍
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• s.4
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• pp.159-162
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• 2004

In order to care about preserving the environment for future generations, each country has been required to make the laws of the environment. So manufacturers must design, manufacture and sell goods that meet customer's need and must do this while meeting the needs of the environment. In this research we have developed product structure and configuration management system that treats electronic catalogs for recycling of train parts. This research focused on two system. One is JAVA-based electronic catalog that give the information about recycling of train parts. The other is product structure and configuration management system based on electronic catalog and Bill of Materials(B.O.M)

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.310-311
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• 2011

본 논문에서는 제주 한림 풍력발전소와 한림 변전소간에 구축할 예정인 ${\pm}80kV$ 60MW HVDC 시스템의 절연 설계를 위해, 각 구성품의 절연 등급을 수 계산으로 설계하였고 PSCAD로 검증하였다. 해당 HVDC 시스템에 영향을 미칠 수 있는 주요 임펄스 중 긴 시간을 가지고 빈번하게 발생 하는 Switching Impulse가 미치는 영향을 모든 상황을 고려하여 모의하였고 수 계산으로 설계된 절연 등급을 검증 하였다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.352-353
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• 2011

본 논문에서는 제주 한림 풍력발전소와 한림 변전소 간에 구축할 예정인 ${\pm}80kV$ 60MW HVDC 시스템의 절연 설계를 위해, 각 구성품의 절연 등급을 수 계산으로 설계하였고 PSCAD로 검증하였다. 각 부분의 절연설계 부분 중, 특히 AC측의 선로에 설치되어 고조파를 저감하는 AC Filter의 절연설계는 고려할 사항이 많다. AC측 선로의 사고, 임펄스 그리고 구성 소자인 인덕터와 커패시터의 설치 구성에 따라 AC Filter의 절연설계가 달라질 수 있다. 따라서 Filter 종류 및 주변 상황요소가 미치는 영향 등 모든 상황을 고려하여 모의하였고 수 계산으로 설계된 절연등급을 검증하였다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.392-393
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• 2011

본 논문에서는 제주 한림 풍력발전소와 한림 변전소간에 구축할 예정인 ${\pm}80kV$ 60MW HVDC 시스템의 절연 설계를 위해, 각 구성품의 절연 등급을 수 계산으로 설계하였다. 계산된 절연등급을 기반으로 한림 변전소와 한림 풍력 단지에 설치되는 HVDC 기기들의 최소 절연거리를 IEC 규격에 맞게 설계하였다. AC/DC 기기의 특정 전압 등급에 견딜 수 있는 최소 거리는 실제 시스템 설치 시 반영함으로써 검증하였다.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.119-121
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• 2000

The protective relay setting of transmission systems has to consider various factors such as the protrected device, relay type and system conditions and it requires the empirical knowledge of experts. In this study. The setting rules have been accumulated in Oracle DB and its inference scheme has been devised. Their applications to relay setting system are expected to refine the setting knowledge enhancing the accuracy and consistency of the relay setting.

• Journal of the Korean Society of Systems Engineering
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• v.1 no.1
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• pp.26-31
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• 2005

In order to care about preserving the environment for future generations, each country has been required to make the laws of the environment. So manufacturers must design, manufacture and sell goods that meet customer's need and must do this while meeting the needs of the environment. In this research we have developed product structure and configuration management system that treats electronic catalogs for recycling of train parts. This research focused on two system. One is JAVA-based electronic catalog that give the information about recycling of train parts. The other is product structure and configuration management system based on electronic catalog and Bill of Materials(B.O.M).

• Journal of the Korean Institute of Gas
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• v.9 no.3 s.28
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• pp.27-31
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• 2005

The membrane to be applied inside of the LNG storage tank is provided with corrugations to absorb thermal contraction and expansion caused by LNG temperature and pressure changes. It is very important to measure their thermal strains under LNG temperature by analytical and experimental stress analysis of the membrane. We have developed a stress measurement system using strain gages and measured the strain during cooldown and storing the LNG. We also analyzed the measured data by comparison with the FEM data.