• 한국항해항만학회지
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• 제35권2호
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• pp.113-119
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• 2011

This paper is a part of the development on the safe navigation model of tugs and barges in Korea waters. desk-top tug-barge simulator is to train the crew of tugs and barges, especially tugs' crew. It is connected with steering and engine telegraph console and winch control console, and can describe three types of operation mode for a tug-barge working unit, towing mode, side by side and push mode. It can also record and assess each simulation run. The evaluation module can confirm the result of a finished simulation run and help trainees to find and correct their faults, and it is composed of result evaluation and process evaluation.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2022년도 추계학술대회
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• pp.170-171
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• 2022

A ship's maneuvering motion model is important in a computer simulation, especially under the trend of intelligent navigation. This model is usually constructed by the hydrodynamic parameters of the ship which are generated by the principles of hydrodynamics. Ship's motion model is a nonlinear function. By using this function, ships' motion elements can be calculated, then the ship's trajectory can be predicted. Deeping neural networks can construct any linear or non-linear equation theoretically if there have enough and sufficient training data. This study constructs some kinds of deep Networks and trains this network by real ship motion data, and chooses the best one of the networks, uses real data to train it, then uses it to predict the ship's trajectory, getting some conclusions and experiences.

• 로봇학회논문지
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• 제19권1호
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• pp.117-129
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• 2024

This paper introduces collective navigation through a narrow gap using a curriculum-based deep reinforcement learning algorithm for a swarm of unmanned aerial vehicles (UAVs). Collective navigation in complex environments is essential for various applications such as search and rescue, environment monitoring and military tasks operations. Conventional methods, which are easily interpretable from an engineering perspective, divide the navigation tasks into mapping, planning, and control; however, they struggle with increased latency and unmodeled environmental factors. Recently, learning-based methods have addressed these problems by employing the end-to-end framework with neural networks. Nonetheless, most existing learning-based approaches face challenges in complex scenarios particularly for navigating through a narrow gap or when a leader or informed UAV is unavailable. Our approach uses the information of a certain number of nearest neighboring UAVs and incorporates a task-specific curriculum to reduce learning time and train a robust model. The effectiveness of the proposed algorithm is verified through an ablation study and quantitative metrics. Simulation results demonstrate that our approach outperforms existing methods.

• 한국항해항만학회지
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• 제30권3호
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• pp.181-187
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• 2006

선형파 이론에 의한 파랑스펙트럼 분포에 의해서는 30m 크기의 파랑은 현실적으로 거의 발생 불가능하다고 인식되어 왔다. 그러나 최근의 위성 영상을 이용한 조사에 의해 3주간의 기간 동안 25m 이상의 거대파가 10개 이상 관측됨에 따라 실해역에서 빈번히 마주칠 수 있는 현상임이 입증되었으며 이에 따라 지금까지 원인 불명으로 치부되어 왔던 많은 해양 재난이 거대파에 의해 발생했던 것으로 추정되고 있다. 거대파의 발생 원인으로는 파군 형성과 관련한 파고분포 특성의 변화, 전파하는 파군의 비선형 공명간섭 등이 제기되고 있으나, 그 출현의 복잡성과 자료의 부족 등으로 아직 명확하게 해명되지 못하고 있다. 본 연구에서는 실해역에서 발생하는 거대파의 실태 및 선형 및 비선형 파랑집중 이론에 근거한 거대파 발생 기구를 고찰하였으며, 비선형 파랑전파를 모사할 수 있는 수치모형을 개발하여 비선형 파랑 집중에 의한 거대 파랑의 형성을 모사하였다.

• 한국소음진동공학회논문집
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• 제26권6_spc호
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• pp.644-650
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• 2016

Track maintenance works based on track geometry recordings are essential to enhance the safety and comfort of railway transportation. Usually, the track irregularity has been measured by a special inspection trains which all were imported from abroad. Because the inspection train speed is limited under 160 km/h, it takes a long time to inspect railways and there is difficulty in daytime operation. To solve this problem, we started to develop a track geometry measuring system (TGMS) with measurement speed up to 300 km/h which can be installed in commercial vehicles such as HEMU-430X. In this paper, we introduce a newly developed inertial TGMS and propose two inertial navigation system (INS) algorithms (method A, B) for measuring track geometry. In order to investigate advantage and disadvantage of each algorithm, we performed vibration test of the TGMS, which was simulated by 6-axis shaking table. Through the vibration test, we analyzed the influence of vehicle vibration on the TGMS which will be installed on bogie frame. To the vibration test, two methods satisfied the required accuracy of track geometry measurement under the level of the actual vehicle vibration of HEMU-430X train. Theoretically, method A is sensitive to vehicle vibration than method B. However, HEMU-430X's bogie vibration frequency range is out of interest range of measurement system. Therefore, method A can also apply the HEMU-430X train.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.773-776
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• 2009

최근의 차량 산업은 차량 내 전자장비들을 하나로 묶을 수 있는 네트워크들이 발달되고, 이에 따라 각각의 네트워크간의 통신이 중요시 되고 있다. 현재 차량에 사용되고 있는 네트워크로는 CAN, LIN, MOST, FlexRay 등이 사용되고 있다. 여러 가지 네트워크들이 생겨나면서 네트워크를 이용한 여러 가지 응용들도 생겨나게 되었고, 이로 인해 운전자들도 좀 더 편리한 환경에서 차량을 운전하고자 하는 욕구가 많아지고 있다. 차량내의 다른 네트워크 환경을 하나의 통합된 환경으로 만들어주기 위한 게이트웨이 연구가 활발히 이루어진다면, 보다 많은 응용들이 개발될 것으로 예상된다. 본 논문에서는 주로 차량의 Body Train 쪽 제어에 사용되는 CAN bus 네트워크와 인포테인먼트 시스템을 제공해주는 MOST 네트워크간의 게이트웨이를 이용한다. 통신을 통해 CAN Node중의 하나인 차량속도를 MOST Navigation 으로 전송하여 차량이 터널에 진입하여 GPS 정보를 얻어올 수 없을 때도 차량의 현재 속도정보를 Gateway를 통해 Navigation으로 실시간으로 전송하는 기술을 이용하는 차량 자동 안전제어 시뮬레이션 시스템 설계하고 구현하고자 한다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 추계학술대회 논문집
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• pp.89-92
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• 2005

특수선은 일반화물과 달리 적$\cdot$양하를 위한 준비가 순차적으로 이루어져야 하며 LNG 및 LPG 운반선은 화물이 극저온 혹은 고압이라는 특성 때문에 고도의 안전성이 요구된다. 또한 인명 안전 및 해상환경 보호를 위해 액화물 취급의 중요성을 인식하면서도 과학적인 장비를 이용한 교육 ·훈련의 관심 부족 및 제도적 지원책이 미비하여 현재까지 해양교육기관에 설치된 장비는 거의 없는 상태이며 그나마 보유하고 있는 장비도 노후되어 원활한 교육$\cdot$훈련이 어려운 실정이다. 따라서, 본 논문에서는 본 연구는 특수선 특히 LNG선박의 적양하 작업을 시뮬레이션 할 수 있는 교육시스템을 개발하는 것이다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1695-1696
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• 2008

KRRI (Korea Railroad Research Institute) is developing a bimodal tram since the 2003s. The vehicle will be used in the public transportation system. The bimodal tram has the advantages of both bus and train. Bus system has the advantages of flexibility of the routes delivering passengers to the destination and easy accessibility. Train is to meet the scheduled arrival and massive public transportations. The vehicle is the rubber tired tram and is all wheel steered single articulation. The propulsion system is configured by CNG hybrid system. The length of the vehicle is 18m. The vehicle lanes will be marked with permanent magnets that are buried in the road. The vehicle can be automatically operated by navigation control system (NCS). In this paper, we introduce the driving system of the bimodal tram which is developed by KRRI.

• 한국항해항만학회지
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• 제35권9호
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• pp.721-727
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• 2011

This paper compares the English language programs of two maritime institutes in very different parts of the world, South Korea and Belgium. It will show that although both institutes comply with the minimum standard set by the STCW Code issued by the IMO, course contents and requirements can vary greatly. Method of class delivery, choice of learning tools and testing will be examined to illustrate some of these differences. This paper will show that in order to train new seafarers in the best possible way that will fulfill the IMO mandate of Safer Shipping and Cleaner Oceans, continual review and development of course curriculum should be an ongoing process that focusing on encouraging cadets to communicate in a targeted, efficient and professional way within a nautical context. This paper will show by comparison the huge potential that the Korean Maritime English program has for positive change and growth.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2003년도 춘계학술발표회
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• pp.77-87
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• 2003

This paper describes recently developed PC based Aids to Navigation Training Simulator (AtoN-TS) using Virtual Reality Modeling language (VRML). The purpose of AtoN-TS is to train entry-level cadets to reduce the amount of sea-time training. The practical application procedure of VR technology to implement AtoN-TS is represented. The construction method of virtual waterway world, according to the guidelines of International Association of Lighthouse Authorities (IALA) is proposed. Design concepts and simulation experiments are also discussed. Results from trial tests and evaluations by subject assessment, provide practical insight on the importance of AtoN-TS.