• 한국국방경영분석학회지
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• 제24권1호
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• pp.88-97
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• 1998

It is critical to determine the appropriate actions for safe landing of an aircraft in an emergency situation. An expert system can be very useful for this purpose. An expert system specifically for jet fighter $F-\bigcirc\bigcirc$ has been developed. Its knowledge base contains the standard procedures provided by various flight manuals and the expertise of human specialists such as pilots and emergency management personnels. Advising procedures are represented by an IF-THEN format in the developed rule-based expert system. Advises are provided in real time during the entire flight processes of ground, takeoff, inflight, and landing. The developed system would significantly increase the survivability of pilots and aircraft, while decreasing operational costs of emergency management personnels. By modifying the knowledge base, the developed system can also be applied to other types of aircrafts including civilian airlines.

• 한국군사과학기술학회지
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• 제16권1호
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• pp.81-88
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• 2013

This paper describes the fundamentals, design, realization and test results of a BPSK(Bi Phase Shift Keying) transceiver for the direction finding proximity fuze sensor for anti-aircrafts or air missiles. The BPSK transceiver for the direction finding fuze sensor has been designed to detect a moving target by Doppler signal processing with the code correlation method and to distinguish direction by comparing received powers of each Doppler signal from adjacent three receiving antennas. The electrical and ESS(Environmental Stress Screening) tests of the BPSK transceiver showed satisfactory results and target detection and direction finding performances proved to be successful through dynamic operation tests by 155 mm gun firing.

• 한국국방경영분석학회지
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• 제23권1호
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• pp.14-24
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• 1997

This study is to develop an optimal surveillance units assignment model in order to obtain the maximized surveillance efficiency with the limited surveillance units. There are many mathematical models which deal with problems to assign weapons such as aircrafts, missiles and guns to targets. These models minimize the lost required to attack, the threat forecast from the enemy, or both of them. However, a problem of the efficient assignment of surveillance units is not studied yet, nevertbless it is important in the battlefield surveillance system. This paper is concerned with the development of the optimal surveillance units assignment model using integer programming. An optimal integer solution of the model can be obtained by using linear programming and branch and bound method.

• 한국국방경영분석학회지
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• 제16권1호
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• pp.113-129
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• 1990

This paper presents the simulation model to decide the mean size of cannibalization aircraft (MSCA) under steady state when an airbase makes use of cannibalization to support the spare parts of an airfleet. In this model, the essential factors such as mission requirements, mission time, failure time, repair time, repair capability, inventory policy, cannivalization rule are considered. The model is constructed with above factors and actual airbase operating rules for a basis. Because of the tangled interdependencies among the each factors, it is inevitable to construct the model by the simulation technique. The mission and support system of the airbase is considered as a closed queueing network with a finite number of unit The troubled aircrafts are repaired in accordance with the priorities that are determined by their repair times. The illustrative example of the model, using the actual data of xx-airbase, is presented. The model would be a useful tool not only to determine the MSCA and the size of scheduled maintenance aircraft but to evaluate the NORS (not operationally ready supply) rate and the availability of an airfleet.

• Journal of Positioning, Navigation, and Timing
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• 제7권1호
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• pp.37-42
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• 2018

This paper proposed a microstrip antenna that can perform jamming of satellite signals from the GPS L5, GLONASS G3, BDS B2 frequency bands (1164 - 1217 MHz) that are employed mainly for military purposes among the GNSS frequencies using unmanned aircrafts over the enemy's sky in time of emergency. The single element in the proposed antenna can be easily mounted to unmanned aircrafts. This study analyzed the characteristics of miniaturization and beam of radiating elements by applying the image theories and perturbation effect to satisfy the uniform level at ${\pm}45^{\circ}$ of beam steering goal due to the phase delay after antenna array. The designed microstrip antenna had a miniaturized radiating element area (x-y plane), which was reduced by 76.3% compared to that of basic microstrip antenna, and its beam width was $190^{\circ}$ in the E-plane and $140^{\circ}$ in the H plane. In addition, the simulation was conducted to determine the characteristics due to the phase delay by arranging the designed single microstrip antenna by $1{\times}4$ array and the results showed that beam steering of ${\pm}45^{\circ}$ is possible in the H-plane on the basis of $0^{\circ}$. Thus, the proposed antenna was verified to be effective in satellite signal jamming in the air as it was attached to the lower end of unmanned aircrafts.

• 대한원격탐사학회지
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• 제15권3호
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• pp.167-175
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• 1999

원격탐사 관련 핵심기술은 최근에 국방, 의료영상, 환경, 지질 등과 같은 광범위한 분야에서 활용범위를 확대하고 있다. 1cm ~ 수십 cm 파장의 파를 관측하는 마이크로파 원격탐사 기술은 반사 적외선 원격탐사나 열 적외선 원격탐사 기술에 비해 날씨조건과 밤낮에 관계없이 탐사를 수행할 수 있다는 장점을 가지고 있다. 마이크로파 영상레이다인 합성 개구 레이다를 이용한 영상화 방식은 응용목적에 따라 stripmap 방식, spotlight 방식, 그리고 inverse 방식으로 구분된다. 본 논문에서는 inverse 방식으로 지상에 고정된 레이다가 비행하는 항공체를 영상화하는 기법에 대해서 기술하였다. 비행 항공체의 영상화 기법은 자동 펴적인식 시스템 구축시 중요한 기술단계이며, 최근 이 분야에 대해 활발히 연구되고 있다. 비행 항공체를 영상화하기 위해 제안된 3가지 방식인 퓨리에 처리 기법, 시간-n 주파수 처리 기법, 그리고 투시로부터 복원 기법을 소개한 후, 각 방식의 장단점을 분석하였다.

• 한국항공운항학회지
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• 제28권1호
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• pp.45-58
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• 2020

According to the Ministry of Land, Infrastructure and Transport press release ('18.12.21.) The amendment of the Aviation Business Act will reduce the capital requirements for aviation leisure operators and make it easier to enter aviation leisure businesses by improving regulations on small air transportation business. In addition, as the scale of the UAV(Unmanned Aerial Vehicle) sector is expected to increase globally, the dramatic increase in low altitude operating aircraft, including this, must be taken into account. The low altitude aircraft category is divided into small airplanes, helicopters, light aircrafts and ultra-light aircrafts, and instructors include school instructor pilots and student pilots, military and national helicopter pilots, and aviation leisure operators. In case of low altitude aircraft, there are cases of canceling operations due to low visibility and low clouds, and aircraft accidents due to excessive operation and sudden weather phenomenon. Therefore, in order to prevent low-altitude aircraft accidents, a safe flight plan based on weather conditions and weather forecasts and more accurate and local weather forecasts and weather forecast data are needed to prepare for the rapidly changing weather conditions.

• 항공우주시스템공학회지
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• 제10권4호
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• pp.105-114
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• 2016

국가간의 지역충돌, 영토, 보호, 대테러 그리고 국제 무역 흐름에 직면한 현 세계는 항공기 수출, 부대파견 및 해외 주둔에 연관되어 감항인증 업무가 증가될 수 있다. 주권 국가의 위치와 책임을 최소화하기 위해서 외국 군 당국사이의 감항인증 절차를 확립하는 것은 중요하다. 이 연구는 항공기 개발 및 운영을 위한 비행 안전을 확보하기 위한 인정 파트너 사이의 군 감항 인정을 연구하였다. 이 논문은 감항 당국의 역할, 감독능력, 생산절차 및 인증의 소개로 미국 및 유럽 군 당국의 인정의제를 분석하였다. 군 당국인정인제를 기본으로, 다른 외국 군당국과 한국군감항당국에 의해 요구되는 규정활동을 감소할 수 있다.

• Structural Engineering and Mechanics
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• 제59권1호
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• pp.123-132
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• 2016

Many military and commercial aging aircrafts flying beyond their design life may experience severe crack and corrosion damage, and thus lead to catastrophic failures. In this paper, were used in a finite element model to evaluate the effect of corrosion on the adhesive damage in bonded composite repair of aircraft structures. The damage zone theory was implemented in the finite element code in order to achieve this objective. In addition, the effect of the corrosion, on the repair efficiency. Four different patch shapes were chosen to analyze the adhesive damage: rectangular, trapezoidal, circular and elliptical. The modified damage zone theory was implemented in the FE code to evaluate the adhesive damage. The obtained results show that the adhesive damage localized on the level of corrosion and in the sides of patch, and the rectangular patch offers high safety it reduces considerably the risk of the adhesive failure.

• 항공우주시스템공학회지
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• 제15권2호
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• pp.36-44
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• 2021

Unmanned aerial vehicles (UAVs) are increasingly needed as they can replace manned aircrafts in dangerous military missions. However, because of their low autonomy, current UAVs can execute missions only under continuous operator control. To overcome this limitation, higher autonomy levels of UAVs based on autonomous situational awareness is required. In this paper, we propose an autonomous situational awareness software consisting of situation awareness management, threat recognition, threat identification, and threat space analysis to detect dynamic situational change by external threats. We implemented the proposed software in real mission computer hardware and evaluated the performance of situational awareness toward dynamic radar threats in flight simulations.