• 한국항공우주학회지
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• 제46권3호
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• pp.269-276
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• 2018

본 논문은 해군 항공의 창시자이자 우리 항공의 개척자이신 조경연 선생님의 업적을 기술하였다. 조경연 선생님은 한국전쟁에 중 버려진 미군 항공기의 부품을 활용하여 다수의 수상 정찰기를 개발하였다. 또한 자신의 주도하에 개발된 항공기들을 바탕으로 해군 항공대를 창설하여 초대 대장으로서 우리 영해의 수호에 헌신하였다. 이로써 우리 해군은 스스로 개발한 항공기를 운용하는 항공부대를 갖게 되었다. 이는 대한민국 해군의 영광스러운 쾌거이자 우리 항공역사의 진정한 시발점이다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권4호
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• pp.1182-1199
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• 2023

Fractional repetition (FR) codes can achieve exact uncoded repair for multiple failed nodes, with lower computational complexity and bandwidth overhead, and effectively improve repair performance in distributed storage systems (DSS). The actual distributed storage system is dynamic, that is, the parameters such as node storage overhead and number of storage nodes will change randomly and dynamically. Considering that traditional FR codes cannot be flexibly applied to dynamic distributed storage systems, a new construction scheme of adaptive-and-resolvable FR codes based on hypergraph coloring is proposed in this paper. Specifically, the linear uniform regular hypergraph can be constructed based on the heuristic algorithm of hypergraph coloring proposed in this paper. Then edges and vertices in hypergraph correspond to nodes and coded packets of FR codes respectively, further, FR codes is constructed. According to hypergraph coloring, the FR codes can achieve rapid repair for multiple failed nodes. Further, FR codes based on hypergraph coloring can be generalized to heterogeneous distributed storage systems. Compared with Reed-Solomon (RS) codes, simple regenerating codes (SRC) and locally repairable codes (LRC), adaptive-and-resolvable FR codes have significant advantages over repair locality, repair bandwidth overhead, computational complexity and time overhead during repairing failed nodes.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권5호
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• pp.1755-1777
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• 2022

The development of wireless communication technology has led to the underutilization of radio spectra. To address this limitation, an intelligent cognitive radio network was developed. Specific emitter identification (SEI) is a key technology in this network. However, in realistic non-cooperative scenarios, the system may detect signal classes beyond those in the training database, and only a few labeled signal samples are available for network training, both of which deteriorate identification performance. To overcome these challenges, a meta-learning-based open-set identification system is proposed for SEI. First, the received signals were pre-processed using bi-spectral analysis and a Radon transform to obtain signal representation vectors, which were then fed into an open-set SEI network. This network consisted of a deep feature extractor and an intrinsic feature memorizer that can detect signals of unknown classes and classify signals of different known classes. The training loss functions and the procedures of the open-set SEI network were then designed for parameter optimization. Considering the few-shot problems of open-set SEI, meta-training loss functions and meta-training procedures that require only a few labeled signal samples were further developed for open-set SEI network training. The experimental results demonstrate that this approach outperforms other state-of-the-art SEI methods in open-set scenarios. In addition, excellent open-set SEI performance was achieved using at least 50 training signal samples, and effective operation in low signal-to-noise ratio (SNR) environments was demonstrated.

• 항공우주시스템공학회지
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• 제14권5호
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• pp.130-138
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• 2020

본 논문에서는 항공 MRO와 해군함정 MRO 산업의 기술공통점을 찾아 국내 MRO 산업규모를 확대할 수 있는 방안을 제시했다. 항공 MRO산업는 유럽과 북미, 싱가폴에서 주도하고 있다. 유럽과 북미는 항공산업 규모가 매우 크다. 그리고 싱가폴에서 MRO산업이 발전한 이유는 항공 MRO와 선박 MRO 산업이 모여 산업규모를 확대했기 때문이다. MRO분야는 연구개발, 생산, 제조, 운용, 폐기 및 승조원 교육훈련까지 전 분야에 걸친 산업이다. MRO산업은 군수용과 민수용으로 구분된다. 하지만 대부분 사용자의 요구사양 차이일 뿐 기술적 차이는 크게 없다. 군이 사용하는 무기체계는 꾸준하게 발전하고 있다. 병력이 감축되는 시기에 군이 모든 장비를 유지보수 하는 것은 불가능하다. 그 때문에 각 분야별로 역할 분담 필요하다. 모든 무기체계를 최적 성능으로 유지하기 위해 민과 군이 협력하는 MRO 산업 필요하다. 그리고 MRO 산업육성은 민수를 기반으로 이뤄져야 한다. 항공기와 해군함정에서 공통적으로 사용되는 장비를 모아 MRO 산업규모를 확대해야 한다. 이를 통해 군의 가용성 확대와 정비예산을 절감할 수 있다.

• 한국항행학회논문지
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• 제27권2호
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• pp.173-181
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• 2023

항공모함은 군용함정이 항공기를 통하여 전투를 수행하기 위하여 항공기의 질서정연한 흐름유지가 필요하다. 항공기 흐름유지는 함정과 항공안전을 강화하기 위한 중요한 요소이다. 항공기 흐름유지를 위해서는 현재 운용 중인 레이더 기반의 감시정보와 CNS 통합 기술에 기반을 둔 감시 장비들에 의한 감시정보를 동시에 수용하여 보다 양질의 관제정보를 제공하는 최첨단 항공관제시스템을 개발이 필수적이다. 이를 위하여 본 연구는 이러한 점에 착안하여 해외 사례를 기초로 우리나라에서 경항공모함을 운영하기 위해 요구되는 항공지원시스템(Aviation Support System)과 항공관제장비(Air Traffic Control System)의 운영에 대해 구체적인 관제 장비의 기능 및 운영 방법 관하여 기술 한다.

• 대한조선학회논문집
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• 제61권2호
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• pp.106-114
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• 2024

In the 21st century, the rapid development of automation and artificial intelligence technologies is driving innovative changes in various industrial sectors. In the transportation industry, this is evident with the commercialization of autonomous vehicles. Moreover research into autonomous navigation technologies is actively underway in the aviation and maritime sectors. Consequently, for the practical implementation of autonomous ships, an effective collision avoidance algorithm has become a crucial element. Therefore, this study proposes a collision avoidance algorithm based on the Obstacle Zone by Target(OZT), which visually represents areas with a high likelihood of collisions with other ships or obstacles. The A-star algorithm was utilized to represent obstacles on a grid and assess collision risks. Subsequently, a collision avoidance algorithm was developed that performs fuzzy control based on calculated waypoints, allowing the vessel to return to its original course after avoiding the collision. Finally, the validity of the proposed algorithm was verified through collision avoidance simulations in various encounter scenarios.

• 대한조선학회논문집
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• 제46권2호
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• pp.179-188
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• 2009

WIG crafts are a high speed vessel with features of dynamic supported craft. These crafts, which are predominantly of light weight and operate any substantially greater speeds than conventional craft such as bulk carrier, tanker, container ship, etc., could not be accommodated under traditional maritime safety instruments. It means that there is the need for risk and safety levels to be assessed on a holistic basis, recognizing that high levels of operator training, comprehensive and thoroughly implemented procedures, high levels of automation and sophisticated software can all make significant contributions to risk reduction. To response this requirement, the Interim Guideline for WIG craft(MSC/Circ.1054) were developed in the view of the configuration of WIG craft, which fall between the maritime and aviation regulatory regimes. This paper reviews a safety assessment process and methodology to be used in the design phase of a new ship. The process and methodology is based on the risk-based approach and is applied to safety assessment in concept development phase of small WIG craft in the 20-person class.

• 대한조선학회논문집
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• 제47권5호
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• pp.697-702
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• 2010

A WIG(Wing-In-Ground effect) craft flies close to the water surface by utilizing a cushion of relatively high pressurized air between its wing and water surface. This implies that when one designs such craft it is important to have lightweight structures with adequate strength to resist external loads with some margins. To investigate this requirement, this paper deals with the structural analysis of the bottom plate of small WIG craft having a design landing weight of 1.2-ton. As building materials for the WIG craft, pre-preg carbon/epoxy composites are considered. The strength information of the bottom plate is obtained using the first-ply-failure analysis in conjunction with a mid-plane symmetric laminated plate theory. As a result, the first-ply-failure location, load and deflection of the bottom plate are obtained. The calculated strength information is compared with the water reaction load for the bottom plate of seaplanes considered when they land on the water surface -the same fluid-structure interaction mechanism as that of WIG craft. In the calculation of seaplane water reaction load information, the rules shown in FAR(Federal Aviation Regulations) Part 25 are used. Through the comparison, the structural integrity of the bottom plate for the WIG craft is checked.

• 한국항행학회논문지
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• 제27권3호
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• pp.293-299
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• 2023

UPRT(Upset Prevention And Recovery Training)은 2001년과 2011년 사이에 상업항공에서 발생한 항공기 사고 중 주요 원인이 LOC-I(비행 중 조종능력상실; Loss Of Control In flight)으로 분석된 이후 3년의 시간에 걸쳐 개발된 사고 예방 훈련 프로그램이다. 2014년 ICAO는 Doc.10011(Manual On Aeroplane Upset Prevention And Recovery Training)을 통해 고정익항공기에 대한 UPRT를 제시하였고 2019년 3월부터 체약국에 의무시행을 권고하였다. 해군 P-3C는 해상초계와 대잠전이 주요 임무이기 때문에 저고도(70~600 m)에서 비행하는 시간이 많고 P-3C 대다수의 조종사들이 비행착각을 경험한바 비정상 자세 예방 및 회복훈련은 해군 P-3C 조종사에게는 반드시 필요한 훈련이다. 이를 위해 본 연구에서는 해군이 보유하고 있는 P-3C 시뮬레이터를 이용하여 제한적인 상태에서의 비정상 자세 예방 및 회복훈련 방안을 제시하고자 한다.

• International Journal of Advanced Culture Technology
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• 제10권4호
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• pp.369-375
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• 2022

The educational environment of the era of age of uncertainty and human and disaster, where nothing is predictable, so it is bringing about many changes. The purpose of this study is to suggest the implications of Integrative arts therapy in the educational field of unpredictable times as a way to move the minds of people living in various educational changes. As for the research method, the characteristics of the integrative arts therapy shown in the previous studies were examined through the literature method, and then through the cases in the modern education environment practiced we propose three things. First, in the field of university education, students should have an integrative arts therapy approach in terms of teaching methods, and also, second, in order to recover from failure and frustration, continuous gratitude sharing training to discover and acknowledge positivity in the situation by changing perspectives should improve students' self-esteem and self-efficacy. Third, professors should play the role of facilitators and also coaches in knowledge transfer. Therefore the coaching process should be integrated into the process of sustainable education when the integrative arts therapy is approached from the pedagogical curriculum.