• Progress in Superconductivity and Cryogenics
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• v.10 no.4
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• pp.23-28
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• 2008

As a part of the plasma control system (PCS) for the first plasma campaign of KSTAR, seven sets of fast feedback control loop for the superconducting poloidal field magnet power supply (PF MPS) have been implemented. A special real-time digital communication interface has been developed for the simultaneous exchanges of the current/voltage data from the 7 sets of 12-thyristor power supplies in a 200 microsecond control cycle. Preliminary power supply tests have been performed before actual cooldown of the device. A $29mH/50m{\Omega}$ solenoid dummy has been fabricated for a series of single power supply tests. Connectivity and response speed of the plasma control system have been verified. By changing hardware cabling, this load was also used to estimate mutual inductance coupling effects of two geometrically adjacent solenoid coils on each power supply. After the cooldown was complete, each pair of the up/down symmetric PF coils has been serially connected and tested as part of the device commissioning process. Bipolar operation and longer pulse attempts have been investigated. The responses of the coils and power supplies corresponding to the plasma magnetic controls in plasma discharges are also analyzed for the future upgrades.

• Proceedings of the Korean Vacuum Society Conference
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• 2009.02a
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• pp.113.2-113.2
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• 2009

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.23.3-23
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• 2001

The main object of this work is the development of an intelligent multi-sensor integration and fusion model that uses fuzzy inference system. Sensor data from different types of sensors are integrated and fused together based on the confidence which is not typically used in traditional data fusion methods. The information is fed as input to a fuzzy inference system(FIS). The output of the FIS is weights that are assigned to the different sensor data reflecting the confidence En the sensor´s behavior and performance. We interpret a type of fuzzy inference system as an interpolator of B-spline hypersurfaces. B-spline basis functions of different orders are regarded as a class of membership functions. This paper presents a model that ...

• Korean Journal of Microbiology
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• v.22 no.1
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• pp.35-40
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• 1984

Attempts were made to optimise protoplast formation and regeneration methods to improve the protoplast fusion frequencies of Streptomyces coelicolor. The yields of protoplast formation and regeneration were varied with different growth phase of the culture. Maximum yields were obtained when cells were taken from the late logarithmic phase. Protoplast formation reached almost its maximum with lysozyme treatment at a concentration of 2mg/ml without any other lytic enzyme. A high frequency of protoplast regeneration was accomplished by overlay method: the method gave 14% recovery of regenerated protoplast versus 1.8% recovery for monolay method. A recombinant frequency of 1.8X10^-2 was obtained by protoplast fusion using PEG 1000(50% w/v).

• Journal of the Korean Vacuum Society
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• v.16 no.5
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• pp.388-396
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• 2007

KSTAR (Korea Superconducting Tokamak Advanced Research) current lead system (CLS) has a role to interconnect magnet power supply (MPS) in room temperature (300 K) and superconducting (SC) bus-line, electrically. For the first plasma experiments, it should be assembled 4 current leads (CL) on toroidal field (TF) current lead box (CLB) and 14 leads on poloidal field (PF) CLB. Two current leads, with the design currents 17.5 kA, and SC bus-lines are connected in parallel to supply 35 kA DC currents on TF magnet. Whereas, it could supply $20\;{\sim}\;26\;kA$ to each pairs of PF magnets during more than 350 s. At the cold terminals of the leads, there are joined SC bus-lines and it was constructed helium coolant control system, aside from main tokamak system, to protect heat flux through current leads and enhanced Joule heat due to supplied currents. Throughout the establishment processes, it was tested the high vacuum pumping, helium leak of the helium lines and hardwares mounted between the helium lines, flow controls for CL, and liquid nitrogen cool-down of possible parts (current leads, CL helium lines, and thermal shield helium lines for CLB), for the accomplishment of the required performances.

• Proceedings of the KIPE Conference
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• 2011.11a
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• pp.253-254
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• 2011

ITER AC/DC 컨버터는 ITER(국제핵융합실험로) 초전도자석에 최대 68 kA의 전류를 공급하는 전원장치이다. ITER AC/DC 컨버터 구조물의 재질선정, 구조설계, 구조 및 전자기력 해석 등을 통하여 컨버터 단위모듈의 실제크기 시제품을 제작하여 정격전류(22.5 kA) 및 단락전류(250 kA) 시험을 성공적으로 완료하였다.

• Proceedings of the KIPE Conference
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• 2011.11a
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• pp.251-252
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• 2011

ITER 기구는 초전도자석 전원장치가 운전 중 발생 가능한 부하의 단락으로부터 장치를 보호하기 위하여 FSC(Fault Suppression Capability) 조건에 만족할 것을 요구하고 있다. 본 연구에서는 모의시험을 통해 FSC 조건에서 발생되는 단락 전류에 의한 소자 이상 유무 및 전자기력의 크기와 방향을 확인하였고, 해석을 통해 전자기력이 전원장치 구조물에 미치는 영향을 검토하였으며, 실제 시험을 통해 모의시험 및 해석 결과가 타당함을 검증하였다.

• Proceedings of the KIPE Conference
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• 2012.11a
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• pp.239-240
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• 2012

ITER 초전도자석 전원공급장치는 대전류를 흘리기 위한 자체 지지구조 버스바와 이를 지지하기 위한 구조물로 구성된다. 장치설계에 있어 버스바와 지지구조물은 단락 시 전자기력에 대한 내성, 통전전류에 의한 버스바 발열 등의 요구조건을 만족하여야 한다. 본 논문은 ITER 초전도자석 전원공급장치에 유한요소해석을 적용하여 여러 요구조건에 부합하는 설계의 적합성을 검증한다.

• Electronics and Telecommunications Trends
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• v.19 no.5 s.89
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• pp.95-106
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• 2004

유비쿼터스 네트워크는 언제, 어디서나, 어떤 기기로도 고품질의 다양한 유비쿼터스 서비스를 가능하게할 것이다. 디지털 홈, 전자정부, e-비즈니스 서비스를 제공하기 위해서 통신서비스, 방송서비스, 인터넷서비스가 BcN을 중심으로 컨버전스 된다고 볼 수 있다. 안전한 유비쿼터스 환경을 위해서는 새롭게 제안하는 fusion security framework의 조기정착이 필수적이며, 이를 위한 기술적 측면의 정보보호와 법적/제도적 측면의 정보보호를 알아보고, 향후의 유비쿼터스 정보보호에 대한 정책적 방향을 제안하고자 한다. 특히, 기술적인 측면에서의 국가 정책방향은 크게 인터넷 안전 대응체계 강화를 위한 u-secureKorea, 깨끗한 사이버 환경 구현을 위한 u-clean Korea, 개인정보보호 환경 구현을 위한 u-privacyKorea의 3가지 분야로 구분할 수 있으며, 3개 분야별로 BcN 인프라 보호기술 개발, 정보침해 방지기술개발, 개인정보 보호기술 개발을 추진하여야 하는 당위성을 제시하고자 한다.

• Microbiology and Biotechnology Letters
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• v.28 no.2
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• pp.80-86
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• 2000

To develop thermotolerant ethanol producing yeast strains, the protoplasts of Saccharomyces carlsbergensis having good fermentability at $30^{\circ}C$ and Kluyveromyces marxianus able to grow at $42^{\circ}C$ were fused. Under the optimal conditions for protoplast formation, the frequency of protoplast formation of S. carlsbergensis was 92 - 94% and that of K. marxianus was 98%. Fusion frequency between S. carlsbergensis and K. marxianus was $1.4\times10^{-6}-4.8$\times10^{-7}$. Among the 27 fusants obtained, 6 fusants were able to grow at $42^{\circ}C$. While the parental strains produced 3.2-3.4%(w/v) ethanol after 3 days from the fermentation medium containing glucose, fusants SK41-4 and SK53-22 produced 5.2%(w/v) ethanol in the same condition. The thermotolerance of SK53-22 was not high, but that of SK41-4 was quite high.