• 한국군사과학기술학회지
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• 제27권2호
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• pp.177-188
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• 2024

The strategic UAV for theater level ISR(Intelligence, Surveillance and Reconnaissance) mission typically has numerous ground targets over area of responsibility(AOR) or area of operation(AO). It is necessary to automatically incorporate these multitude of ground targets into mission planning process in order to collect ISR images before actual flight mission. In addition, weather information such as wind direction and/or velocity may have significant impacts on the qualities of collected sensor images, especially in SAR(Synthetic Aperture Radar) images. Thus weather factors in the operation altitude should also be considered in the mission planning stage. In this study, we propose a novel mission planning scheme based on target scheduling and deviation correction method incorporating weather factors.

• 한국군사과학기술학회지
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• 제27권3호
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• pp.416-427
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• 2024

The wake-homing underwater guided weapon that detects and tracks wake generated during voyage of a surface ship is impossible to avoid with the present acoustic deception torpedo defense system. Therefore, research on bubble-generating wake decoy is necessary to deceive wake-homing underwater guided weapon. Experiments in various environments are required to verify the effective operation method and performance of the wake decoy, but performance verification through underwater experiment is limited. In this paper, we develop a simulator for an torpedo defense system of surface ship, which is applied bubble-generating wake decoy, against acoustic, wake, and hybrid homing underwater guided weapon attack. The simulator includes surface ship model, acoustic decoy(static, mobile) model, bubble-generating wake decoy model, search and motion model of underwater guided weapon and so on. By integrating various models, MATLAB GUI simulator was developed. Through the simulation results for various environmental variables by this simulator, it is judged that effective operation method and performance verification of the bubble-generating wake decoy can be performed.

• 대한원격탐사학회지
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• 제24권6호
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• pp.591-603
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• 2008

위성의 성능은 위성의 최종생산물인 위성 영상 품질에 의해 평가된다. 위성 영상의 품질을 평가하는 요소로는 광학적요소인 변조 전달함수(Modulation Transfer Function : MTF), 신호대잡음비(Signal To Noise Ratio : SNR), 기하학적 요소인 해상도(Ground Sample Distance : GSD) 등이 있으며, 위성의 설계 단계에서 위성의 설계 및 제작, 관측 및 운영 환경을 반영하여 위성 영상의 품질을 예측하는 것은 필수적이다. 본 연구에서는 위성의 설계 단계에서 위성 설계 및 운용 조건을 반영한 영상 품질 시뮬레이션 방법을 제시한다. 본 연구의 결과를 통해 위성의 설계 시 영상 품질 예측에 활용 될 수 있으며, 수신된 영상의 화질 개선 연구에 활용될 것으로 기대된다. 또한 항공 영상의 품질 시뮬레이션에 확대 적용할 수 있을 것으로 기대된다.

• 한국전기전자재료학회논문지
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• 제34권6호
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• pp.466-474
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• 2021

[011] poled ternary Pb(In_1/2Nb_1/2)O₃-Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ (PIN-PMN-PT) single crystals have been investigated for active materials for acoustic transducers because of their high piezoelectric properties in both shear and transverse modes. In order to use [011] poled PIN-PMN-PT single crystals for acoustic transducers, the characterization of full-matrix material properties is required. In this study, full sets of compliance, dielectric, and piezoelectric constants of [011] poled rhombohedral PIN-PMN-PT were measured by a resonance method. Dimensions and geometries of 12 samples were proposed for measuring 17 independent material constants of [011] poled rhombohedral PIN-PMN-PT single crystals. Two sets of samples with different PT concentrations, 0.24PIN-0.49PMN-0.27PT and 0.24PIN-0.46PMN-0.30PT, were fabricated and their material properties were measured. Measured impedance spectra and simulated impedance spectra of the samples were compared to check the accuracy of the measurements.

• 한국군사과학기술학회지
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• 제24권5호
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• pp.482-491
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• 2021

It is obvious that understanding the effects of shallow water environment of Korea is very important to guarantee the optimal performance of active sonar such as monostatic and bistatic sonar. For this reason, in this paper, we analyzed the detection performance characteristics for various depth deployments of sonar in summer, winter and water temperature inversion environments, which environments are frequently observed in shallow water of Korea such as the Yellow sea. To analyze only effects of water temperature structures on target detection performance, we applied range independent conditions for bottom, sea surface and water temperature characteristics. To understand the characteristics of detection performance, we conducted transmission loss and signal excess modeling. From the results, we were able to confirm the characteristics of detection performance of active sonar. In addition, we verified that operation depth of transmitter and receiver affects the detection performance. Especially in the water temperature inversion environment, it was confirmed that the shadow zone could be minimized and the detection range could be increased through bistatic operation.

• 한국군사과학기술학회지
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• 제24권3호
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• pp.328-338
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• 2021

A study on common modular design based on open standards to reduce the life cycle cost of ground weapon system is underway. Since the ground weapon system includes major mission equipment such as fire control system, it is essential to apply the concept of fault tolerance through automatic reconfiguration and blocking unspecified equipment through connectivity control. However, it is difficult to generalize due to the difference in operating characteristics for each system. In this paper, we propose a plug-and-play framework, which includes plug-and-play architecture and mechanism. The proposed method can be used in common by the application of each component as it is divided into a common service layer. In addition, the proposed connectivity control and autonomous reconfiguration method facilitates reflection of operating characteristics for each system. We constructed a verification environment that can simulate ground weapon systems and components, and verified that the proposed framework works through scenario-based functional tests.

• 한국군사과학기술학회지
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• 제24권4호
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• pp.382-391
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• 2021

Unsupervised domain adaptation often gives impressive solutions to handle domain shift of data. Most of current approaches assume that unlabeled target data to train is abundant. This assumption is not always true in practices. To tackle this issue, we propose a general solution to solve the domain gap minimization problem without any target data. Our method consists of two regularization steps. The first step is a pixel regularization by arbitrary style transfer. Recently, some methods bring style transfer algorithms to domain adaptation and domain generalization process. They use style transfer algorithms to remove texture bias in source domain data. We also use style transfer algorithms for removing texture bias, but our method depends on neither domain adaptation nor domain generalization paradigm. The second regularization step is a feature regularization by feature alignment. Adding a feature alignment loss term to the model loss, the model learns domain invariant representation more efficiently. We evaluate our regularization methods from several experiments both on small dataset and large dataset. From the experiments, we show that our model can learn domain invariant representation as much as unsupervised domain adaptation methods.

• 한국군사과학기술학회지
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• 제27권2호
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• pp.277-284
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• 2024

For the high reliability of guidance weapon, it is important to maintain the stable supply voltage for guidance system while the bomb is gliding. However, the DC motor drive for guidance control in the low temperature can lead to the critical voltage drop due to a large inrush current. In this paper, we propose the wing deployment logic design to enhance the guidance system stability. To derive the stable drive logic based on PWM, we controlled the duty cycles for input voltage of DC motor in low temperature. The initial duty cycle was set to 40 % to relieve the inrush current. Moreover, the proper time, which is less than 1 second for controlling duty cycles, was determined by the iterative wing deployments of guidance kit. Finally, the validity of proposed logic was confirmed from the result the maximum voltage drop for the wing deployment was decreased by 23 %.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2022년도 춘계학술대회
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• pp.66-68
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• 2022

데이터 활용이 점점 중요해짐에 따라 민간 기업뿐만 아니라 공공기관에서도 데이터 활용 활성화를 위해 많은 노력을 기울이고 있다. 그 중에서도 데이터책임관 제도는 데이터 정책을 담당하는 조직의 각 부서의 기능을 조정하여 정책 목표를 달성해 나가는 추진체계인 데이터 거버넌스의 핵심 요소이다. 데이터기반행정 법이 시행됨에 따라 국방부를 포함한 모든 공공기관이 데이터책임관을 지정하였지만, 아직 도입 초기임에 따라 실질적인 역할을 하기에는 역부족이다. 본 연구에서는 현재 국방부에서 추진 중인 국방데이터책임관 제도 운영 현황을 점검해보고, 실질적인 역할을 하기 위한 발전방안을 제시한다.

• 전자통신동향분석
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• 제28권2호
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• pp.132-144
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• 2013

국방과학기술은 중장기 기획문서체계에 의해 체계적인 기술기획이 수립되고 있다. 또한 합동참모본부의 전략문서와 연계하여 국방과학기술의 중장기 전략을 수립한다. 무기체계는 지휘통제, 감시정찰 및 정밀타격체계로 구성되고, 핵심기술은 정보통신, 센서, 플랫폼 등 8대 기술 분야로 구성된다. 국방정보 기술은 국방에 관한 정보를 생산, 유통 또는 활용하여 국방 분야의 제반 활동을 가능하게 하거나, 미래 전장운용 개념 구현 및 국방경영 효율화를 지원하여 국방비전 및 국방개혁을 달성하는 핵심 기능 역할을 수행하는 것을 의미한다. 국방정보 기술 개발의 목적은 한반도 전 구역에서 실시간 및 근실시간으로 요구 수준 및 정확성을 확보하기 위해 전장가시화, 네트워크화된 지휘통제, 효과 중심 정밀타격, 전쟁지속을 위한 인사, 군수, 동원 등 통합지원체계를 구축하여 미래전 양상과 국방정보화의 특성을 고려한 실시간 정보공유 및 관리 가능한 정보화 환경을 구축하는 데 있다. 본고는 국방정보 기술 체계 및 요소기술에 대한 특성과 적용기술 및 발전 방향을 살펴본다.