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        검색결과 135

        1.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        As technologies have been more quickly developed in this 4th Industry Revolution era, their application to defense industry has been also growing. With these much advanced technologies, we attempt to use Manned-Unmanned Teaming systems in various military operations. In this study, we consider the Location-Routing Problem for reconnaissance surveillance missions of the maritime manned-unmanned surface vehicles. As a solution technique, the two-phase method is presented. In the first location phase, the p-median problem is solved to determine which nodes are used as the seeds for the manned vehicles using Lagrangian relaxation with the subgradient method. In the second routing phase, using the results obtained from the location phase, the Vehicle Routing Problems are solved to determine the search routes of the unmanned vehicles by applying the Location Based Heuristic. For three network data sets, computational experiments are conducted to show the performance of the proposed two-phase method.
        4,000원
        6.
        2023.11 구독 인증기관·개인회원 무료
        If radioactive plumes are released outside due to loss of containment building integrity during a nuclear power plant accident, these materials might travel with the wind, affecting both the surrounding environment and neighboring countries. In China, most nuclear power plants are located on the eastern coast. Consequently, a radioactive plume generated during an accident could negatively impact even the western part of the Korean Peninsula due to westerly winds. To detect such problems early, respond quickly, and protect residents, a system that can monitor aerial radiation under normal conditions is needed. Additionally, a detection system that can operate in real-time in an emergencies conditions is required. The current method for aerial radiation measurement takes environmental radiation data from a monitoring post 1.5 m above the ground and converts it to altitude. To measure actual aerial radiation, an expansive area is surveyed by aircraft. However, this approach is both time-consuming and expensive. Thus, to monitor radioactive plumes influenced by environmental factors like wind, we need a radiation detector that can gauge both radioactivity and directionality. In this study, we developed a radiation detector capable of assessing both the radioactivity and directionality of a radioactive plume and conducted its performance evaluation. We miniaturized the radiation detector using a CZT (Cadmium Zinc Telluride) sensor, enabling its mounting on unmanned aerial vehicles like drones. It is configured with multi-channels to measure directionality of a radioactive plumes. For performance evaluation, we positioned two-channel CZT sensors at 90 degrees and measured the energy spectrum for angle and distance using a disk-type radioactive isotope. Using this method, we compared and analyzed the directionality performance of the multi-channel radiation detector. We also confirmed its capability to discern specific radioactivity information and nuclide types in actual radioactive plumes. Our future research direction involves mounting the multi-channel radiation detector on a drone. We aim to gather actual aerial radiation data from sensors positioned in various directions.
        7.
        2023.06 구독 인증기관 무료, 개인회원 유료
        With the continuous development of science and technology, unmanned ship has gradually become a hot spot in the field of marine research. In practical applications, unmanned ships need to have long-range navigation and high efficiency, so that they can accurately perform tasks in the marine environment. As one of the key technologies of unmanned ship, path planning is of great significance to improve the endurance of unmanned ship. In order to meet the requirements, this paper proposes a path planning method for long distance unmanned ships based on reinforcement learning angle precedence ant colony improvement algorithm. Firstly, canny operator is used to automatically extract navigation environment information, and then MAKLINK graph theory is applied for environment modelling. Finally, the basic ant colony algorithm is improved and applied to the path planning of unmanned ship to generate an optimal path. The experimental results show that, compared with the traditional ant colony algorithm, the path planning method based on the improved ant colony algorithm can achieve a voyage duration of nearly 7 km for unmanned ships under the same sailing environment, which has certain practicability and popularization value.
        4,000원
        8.
        2023.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 무인항공기인 드론을 활용한 VDMS(Vision-based Displacement Measurement System)를 통해 동적변위계측 정 확도와 동특성 추정 신뢰성 검증을 위한 동적실험을 실시하였다. 비행하는 드론의 이동 및 회전진동을 보정하기 위해 영상 내부의 변 위가 발생하지 않는 고정점을 활용한 보정밥법을 사용하였으며, 검증을 위해 설치한 범용 센서인 LVDT와 LDS의 변위계측 결과와 비 교하여 그 오차를 시간영역과 진동수영역에서 분석하였다. 3가지 타입의 장비 모두 최대 변위 도달 및 주기 운동 계측에 있어서 대체 적으로 유사한 결과를 나타내었다. LDS 기준의 오차 분석 결과, 드론과 LVDT는 가진 진동수 변화에 의한 오차 값은 미비하나, 최대 발생 변위가 작을수록 오차 값은 증가하였다.
        4,000원
        12.
        2023.05 구독 인증기관·개인회원 무료
        Airborne surveys are an essential analysis method for rapid response and contamination identification in the early event of a radiation emergency. On the other hand, airborne surveys are far from the ground, so it is necessary to convert the dose rate at a height of 1 m above the ground. In order to improve the accuracy of the analysis value, a lot of analysis of the measurement data is required. In our previous research, we developed MARK-A1, an instrument for rapid radiation aerial survey in high radiation environment, and MARK-M1, a multipurpose instrument for radiation detection. In this study, a large unmanned aerial vehicle (UAV) was used to conduct airborne surveys using three types of detectors in the Jeju Island environment. The NaI(Tl) detector uses one 3-inch scintillator (38 mm φ × 38 mm H), and the LaBr3 detector uses two 2-inch scintillators (25 mm φ × 25 mm H). The CZT detector uses a detector with dimensions of (15 mm × 15 mm × 7.5 mm). The UAV has a payload of 15 kg (J10, JCH systems Inc. Seoul, Korea). Three different detectors were operated at a constant height of 20 m, 30 m, and 50 m. The flight experiments were performed in the west near Jeju City. Dose rate conversion factors were used to convert the dose rate from the measured spectra, and hovering flights were conducted between 1 and 50 meters to derive altitude correction factors. In this paper, the data measured with each detector in the same area were compared and the differences were derived.
        14.
        2023.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 소나무재선충의 매개충인 솔수염하늘소와 북방수염하늘소에 대하여 무인항공기 (무인헬리콥터)를 이용하여 스피네토람의 약효 및 약해를 조사하였다. 하늘소를 대상으로 등록된 펜토에이트 유제, 비펜트린 액상수화제, 하늘소를 제외한 딱정벌레가 대상인 에토펜프록 스 유제, 디플루벤주론 수화제와 나방류에 방제 약제로 등록된 인독사카브 수화제, 스피네토람 액상수화제 6종을 ULV기로 살포하여 솔수염하 늘소에 대한 섭식독과 접촉독을 확인한 후 선발하였다. ULV 시험 결과, 펜토에이트, 비펜트린, 인독사카브, 스피네토람의 33배, 55배 희석배수 액은 처리후 3일차에 접촉독과 섭식독에서 100% 살충율을 보였으나, 에토펜프록스는 7일차 접촉독 살충율 88.9%(33배), 88.9%(50배), 섭식독 살충율 93.4%(33배, 50배), 디플루벤주론은 7일차 접촉독 살충율 83.3%(33배), 섭식독 80.3%, 53.9%(50배)로 조금 낮은 살충률을 보였다. ULV 시험에서 선발된 가장 적합한 스피네토람의 33배액을 무인항공기로 살포하여 솔수염하늘소와 북방수염하늘소에 대한 감수성을 평가한 결 과, 98.6% - 100%의 살충율을 보였다. 그러나, 해당 약제의 매개충 방제에 적용하기 전에 항공 살포에 의한 꿀벌에 대한 위해성 평가가 필요할 것 으로 판단되었다.
        4,000원
        15.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 논문에서는 해상 위험유해물질(Hazardous Noxious Substances, HNS) 사고의 효과적인 대응을 위해 개발된 부유식 무인이동체 기반 광역탐지 및 모니터링 시스템의 운용 시나리오 설계와 실험 검증 내용을 보인다. 광역탐지 및 모니터링 시스템은 장시간 운용이 가 능하되 제한적 이동이 가능한 무계류형 부이 형태를 갖는 부유식 무인이동체 플랫폼을 기반으로 개발되었으며 임무 수행에 필요한 열화 상 카메라, 레이더, 부유 및 대기 HNS의 탐지를 위한 센서가 탑재되었다. 실험 검증 과정에서는 탐지 센서 성능을 야외 환경에서 실험적 으로 검증하기 위해 이동식 가스 유출 시스템(Portable Gas-exposure System, PGS)을 추가로 설치하였다. 무인 시스템의 원격 및 자율 운용을 위해 전체 운용 소프트웨어는 로봇운영체제(Robot Operating System, ROS) 프레임워크를 기반으로 통합되었다. 내수면 및 실해역에서의 실 험을 통해 개발된 시스템의 운용 및 활용 가능성을 실험적으로 검증하였다.
        4,000원
        16.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Recently, unmanned logistics delivery systems, such as UAV (Unmanned Aerial Vehicle, written as drone below) and autonomous robot delivery systems, have been implemented in many countries due to the rapid development of autonomous driving technology. The development of these new types of advanced unmanned logistics delivery systems is essential not only to become a leading logistics company but also to secure national competitiveness. In this paper, the application of the unmanned logistics delivery system was investigated in terms of market trends, overall technology level of last mile delivery drone and autonomous delivery robot. The direction of response to changes in the last mile delivery service market was checked through a comparison of the technological level between domestic companies that produce last mile devices and advanced foreign companies. As a result of this technology level analysis, the difference between domestic companies and advanced companies was shown using tables and figures to show their relative levels. The results of this analysis reflect the opinions of experts in the field of last-mile delivery technology. In addition, the technology level of unmanned logistics delivery systems for each country was analyzed based on the number of related technology patents. Lastly, insights for the technology level analysis of unmanned last mile delivery systems were proposed as a conclusion.
        4,000원
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