• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.7
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• pp.2528-2533
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• 2010

This paper describes on a software simulator that can be used for an anti-ARM system. The proposed simulator is a valuable tool for investigating the optimum deployment of decoy antennas which are widely using for anti-ARM and calculating the electromagnetic field at the ARM receiver. To verify the effect of decoy antennas, we analyze the field intensity and phase at the receiver. We conduct an analysis of ARM attack in case of using multiple decoy antennas and the proposed simulator can be used to decide the optimum positions of the decoys.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.2
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• pp.147-155
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• 2016

This paper presents a jamming detection and suppression algorithm of a frequency-modulated continuous-wave(FMCW) radar altimeter. The radar altimeter measures the noise level at the noise measuring period before the transmitting and receiving period and finds the number of sampled noise data over the jamming threshold for detecting the jamming. For a jamming suppression technique, we design the time domain jamming suppression, transmit/receive power control and frequency hopping methods. To assess more realistic operation, the radar altimeter was performed a field test. Through the field test, we verified the algorithms successfully.

• Proceedings of the KAIS Fall Conference
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• 2010.11a
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• pp.134-137
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• 2010

본 논문에서는 대방미사일(ARM: Anti Radiation Missile)로부터 레이다를 보호하기 위하여 디코이 안테나를 이용한 전파회피기술을 효과적으로 모의하기위한 시뮬레이터를 제안하자 한다. 제안된 시뮬레이터는 디코이(Decoy) 안테나의 효과적인 배치와 ARM 수신기에 수신되는 전파의 특성 분석이 가능하도록 설계되었다. 디코이 안테나의 배치 효과를 검증하기위해서 ARM 수신기에 도달하는 디코이 안테나 신호의 위상과 진폭을 분석 결과를 제시하였다. 또한 다수 디코이 안테나를 사용하는 경우 ARM의 공격효과를 다양하게 분석하였으며 ARM 방어를 위한 효과적인 디코이 배치에 유용하게 활용 될 것이다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.2
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• pp.491-496
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• 2010

This paper describes an analysis of the effectiveness for an anti-ARM technique to protect a radar system. We investigate the optimum deployment of decoy antennas which are widely using for anti-ARM and the electromagnetic field at the ARM receiver. To verify the effect of decoy antennas, we analyze the field intensity and phase at the receiver and develop a numerical simulation program using Matlab. We conduct an analysis of ARM attack in case of using multiple decoy antennas and these results can be used to decide the optimum positions of the decoys for anti-ARM.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11c
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• pp.1453-1456
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• 2003

데이터의 중복은 데이터의 가용성과 시스템의 성능을 향상시키기 위해 사용한다. 대규모 부분 중복 데이터베이스에서 효율적인 중복 관리를 위해서는 정확한 수행을 보장하기 위한 정확성 검증방법과 효율적인 갱신 전파 방법이 필요하다. 이 논문에서는 부분 중복 환경에서 각 주사본 사이트의 중복 데이터에 대한 트리 구조를 기반으로 한 갱신 전파 방법을 제시하며, 갱신 지연 전파로 인해 갱신 전파도중에 발생할 수 있는 전파 트랜잭션과 주 트랜잭션의 충돌로 인한 비직렬성 문제를 타임스탬프와 상태 데이터베이스를 이용하여 해결한다. 이것은 판독 가용성을 증가시키면서 비직렬성으로 인한 재수행을 회피하게 되어 트랜잭션의 완료율을 증가시킨다.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.1517-1520
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• 2008

최근의 사이버 공격은 경쟁사에 대한 DDoS 공격과 기밀정보 유출, 일반 사용자들의 금융정보 유출, 광고성 스팸메일의 대량 발송 등 불법 행위를 대행해주고 경제적 이득을 취하려는 의도로 바뀌어 가고 있다. 그 중심에 있는 봇넷은 봇이라 불리는 감염된 호스트들의 네트워크 집단으로서 일련의 거의 모든 사이버 공격에 이용되고 있다. 이러한 봇넷은 수 많은 변종과 다양한 탐지 회피 기술로 그 세력을 확장해가고 있지만 마땅한 총괄적 대책은 미흡한 것이 현실이다. 이 논문에서는 날이 갈수록 위협을 더해가는 봇넷을 빠르게 탐지하고 대응하기 위해 ISP 사업자들 간, 혹은 국가 간에 걸친 사회 전반적인 협력을 통한 봇넷 탐지 및 관리 시스템 구조를 제안한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.7
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• pp.605-611
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• 2013

If an accident vehicle propagates emergency messages to other vehicles close to it, the other drivers may realize and avoid the accident spot. In this letter, we propose a broadcast scheme to propagate emergency messages fast in urban VANETs (Vehicular Ad-Hoc Networks) with the help of GPS (Global Position System). In our scheme, a transmitting vehicle chooses the farthest node as the next relay vehicle to propagate emergency messages. And, we suggest an algorithm for intersection recognition and SCF (Store-Carry-Forward) task by taking advantage of periodic hello packets to reduce the propagation time and enhance the delivery ratio.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.10
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• pp.918-926
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• 2007

Military aircrafts usually operate at the area with lots of threats such as radars and surface-to-air missiles. Aircraft also faces with the unexpected or pop-up threats. Under this environment, a safe flight path should be generated to lead a mission successful. In this paper, a new path planning algorithm is proposed to provide less dangerous flight path efficiently. Of many path planning algorithms, a potential method is considered, because it has advantages of computation efficiency and smooth path generation. Trajectory generation under the condition of maximum range is studied so that the aircraft may reach the target area without refueling. The algorithm to cope with an unexpected situation is also proposed by adopting the concept of initial direction vector, additional force, and a new mapping function. The performance of the proposed algorithms is demonstrated for SEAD (Suppression of Enemy Air Defences) mission by numerical simulation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.1043-1046
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• 2006

Cached data management of clients is required to guarantee the correctness of client's applications. There are two categories of cache consistency algorithms : detection-based and avoidance-based cache consistency algorithm. Detection?.based schemes allow stale data access and then check the validity of any cached data before they ran be allowed to commit. In contrast, under avoidance-based algorithms, transactions never have the opportunity to access stale data. In this paper, we propose a new avoidance-based cache consistency algorithm make use of version. The proposed method maintains the two versions at clients and servers, so it has no callback message and it can be reduced abort ratio of transactions compare with the single-versioned algorithms. In addition to, the proposed method can be decreased cache miss using by mixed invalidation and propagation for remote update action.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2646-2650
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• 2009

This paper describes an anti-ARM technique using multiple decoy antennas. We investigate the radar and decoy antenna signal received at the ARM receiver to verify the effect of decoy antennas. And we develop a simulation program using Matlab for optimum positions of the decoys and the effect of ARM by distance between decoys. We suggest optimum positions and distance between decoys based on our simulation results.