• Progress in Superconductivity and Cryogenics
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• v.10 no.1
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• pp.42-47
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• 2008

In this paper, the fault current limiting characteristics for the superconducting fault current limiter(SFCL) using magnetic coupling between two coils were investigated. The SFCL consists of a high-$T_c$ superconducting(HTSC) element and two coils. This SFCL has different characteristics that depend on the connection form, the winding direction and the inductance ratio of two coils. The impedance and the operational current of the SFCL can be adjusted higher or lower than the resistance and the critical current of HTSC element. Therefore, the SFCL can change the amplitude of the limited fault current. To confirm it, the HTSC element was modeled and the fault current limiting characteristics of the SFCL were analysed through computer simulation. It was obtained from the analysis that the connection form and the winding direction of two coils of the SFCL were the important design parameters.

• Defense and Technology
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• no.1 s.13
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• pp.50-53
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• 1980

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.1
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• pp.21-30
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• 2020

In this paper, we predicted the propagation loss for the air-to-ground (A2G) channel between the ground control system and the unmanned aerial vehicle (UAV) using the prediction model for the aircraft recommended by the International Telecommunication Union (ITU). We analyzed the network coverage of the aerial relay system based on the medium altitude UAVs by expanding it into the air-to-air (A2A) channel. Climate and geographic factors in Korea were used to predict propagation loss due to atmospheres. We used the measured data published by the Telecommunication Technology Association (TTA) for regional rainfall-rate and effective earth radius factors to increase accuracy. In addition, the aerial relay communication system used the key parameter of the common data link (CDL) system developed in Korea recently. Prediction results show that the network coverage of the aerial relay system broadens at higher altitude.

• Defense and Technology
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• no.4 s.290
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• pp.44-53
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• 2003

Hawk에 대한 미래의 계획은, Raytheon/Kongsberg사가 네덜란드 육군 및 공군용으로 개발한 Hawk-AMRAAM 방공시스템의 경우처럼, Raytheon사의 AIM-120 AMRAAM 공대공 미사일을 육상 발사형으로 개조하여 Hawk와 결합시키는 시스템에 초점이 모아지고 있다. AIM-120 미사일은 다수의 고속, 저고도 표적을 요격하기 위해서 사용되며, 사거리는 약 20km이고 최소 발사 간격은 2초 이내이다. 이러한 Hawk/AIM-120 조합을 통해서 Hawk의 장거리 및 고고도 표적에 대한 교전능력을 유지하면서, 작은 레이더 단면적 표적에 대한 Hawk ILM 미사일의 우수한 요격능력도 보유할 수 있게 된다.

• Defense and Technology
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• no.8 s.138
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• pp.68-75
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• 1990

휴즈 항공사는 1050년대에 최초로 공대공 유도 미사일인 팰콘(Falcon)을 개발한이래 30여년 이상 첨단 전자기술분야에 참여하고 있다. 오늘날 휴즈사는 전자분야에서 미국내 가장 큰 방산업체이다. 휴즈사는 현재 유도 미사일, 항공전자, 통신위성, 전자광학, 항공기 레이다, 항공방위 지휘통제 시스템, 산업전자, 모의장비 및 훈련등 광범위한 기술분야에 참여하고 있다. 원래 세계군사장비에 탑재되는 항공전자장비 개발업체로 알려진 휴즈사는 신기술을 민수분야와 산업분야에 적용하였으며, 이에따라 우주시스템, 통신 서비스, 모의장비, 기타 첨단 전자 장비 및 민수용 장비 개발업체로 발전하였다. 지난 몇년동안 휴즈사는 미 국방부 매출액 10위권의 업체로 성장하였다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.7
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• pp.660-665
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• 2011

Reconfigurable Flight Simulator for an airborne tactical mission based on virtual reality technology is developed as a software configurable cockpit with computer display as virtual instruments. It can simulate F-15K, KF-16, T/A-50 class fighter and depending on simulated cockpit, control stick and throttle are replaceable. For effective immersion, Video See-Through type HMD is applied.

• Defense and Technology
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• no.11 s.93
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• pp.33-36
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• 1986

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.16 no.4
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• pp.340-349
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• 1987

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.6 no.1
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• pp.9-14
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• 1977

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.8 no.2
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• pp.114-121
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• 1979