• 한국항해항만학회지
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• 제47권2호
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• pp.75-84
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• 2023

Ships need to ensure safety during their navigation, which makes route determination highly important. It must be accompanied by a route following controller that can accurately follow the route. This study proposes a method for automatically generating the ship route based on deep reinforcement learning algorithm and following it using a route following controller. To generate a ship route, under keel clearance was applied to secure the ship's safety and navigation chart information was used to apply ship navigation related regulations. For the experiment, a target ship with a draft of 8.23 m was designated. The target route in this study was to depart from Busan port and arrive at the pilot boarding place of the Ulsan port. As a route following controller, a velocity type fuzzy P ID controller that could compensate for the limitation of a linear controller was applied. As a result of using the deep Q network, a route with a total distance of 62.22 km and 81 waypoints was generated. To simplify the route, the Douglas-Peucker algorithm was introduced to reduce the total distance to 55.67 m and the number of way points to 3. After that, an experiment was conducted to follow the path generated by the target ship. Experiment results revealed that the velocity type fuzzy P ID controller had less overshoot and fast settling time. In addition, it had the advantage of reducing the energy loss of the ship because the change in rudder angle was smooth. This study can be used as a basic study of route automatic generation. It suggests a method of combining ship route generation with the route following control.

• Journal of Advanced Marine Engineering and Technology
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• 제25권1호
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• pp.199-208
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• 2001

In this paper, an automatic route tracking algorithm using the position variables and the yaw angle of a ship is suggested, Since most autopilot systems paly only a role of course-keeping by integrating the gyrocompass output, they cannot cope with position errors between the desired route and real route of the ship resulted from a drifting and disturbances such as wave, wind and currents during navigation. In order for autopilot systems to track the desired route, a method which can reduce such position errors is required and some algorithms have been proposed[1,2]While such were turned out effective methods, they have a shortage that the rudder control actions for reducing the position errors are occurred very frequently. In order to improve this problem it is necessary to convert that error into the corresponding yaw angle and necessary to treat only yaw angle control problem. To do this a command generation algorithm which converts the rudder angle command reducing the current position error into they yaw angle command is suggested. To control the ship under disturbances and nonlinearities of the ship dynamics, the adaptive fuzzy controller is developed. Finally, through computer simulations for two ship models, the effectiveness of the suggested method and the possibility of the automatic route tracking are assured.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.995-1000
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• 2003

This paper proposes the pedestrian navigation system which deals with subjective information. This system consists of the route setting part and the instruction generation part. The route setting part chooses the route with highest subjective satisfaction degree. The instruction generation part gives users the instructions based on the users' sensuous feeling of distance with linguistic expressions. Fuzzy measures and integrals are applied to the calculation of the satisfaction degree of the route which reflects the users' taste for routes. The instruction generation part has database of users' cognitive distance. Users' cognitive distances are expressed by fuzzy sets that correspond to linguistic terms. The system generates the instructions with linguistic terms which have the highest fitness value for the users' sensuous feeling of distance. This paper also performs subjective experiments in order to confirm the validity of the present system.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2012년도 추계학술대회
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• pp.119-120
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• 2012

국제수로기구(IHO)는 수로분야의 다양한 데이터와 서비스에 관한 표준개발을 위한 프레임워크로 S-100 표준을 개발하였고 이를 기반으로 차세대 전자해도 표준을 포함하여 제품 및 서비스에 관한 표준연구가 진행되고 있다. ECDIS 및 항해관련 시스템에서는 항해를 위한 항로계획을 수행하는데 생성되는 항로정보에 대한 표준규격의 저장 및 활용이 필요성이 높아 S-100 표준에 기반한 항로정보 표준 연구가 수행된 바 있다. 항로정보 표준은 다양한 항해관련 시스템에서 생성하는 항로정보를 상호 운용하기 위한 것으로 적용 가능성 검토가 요구된다. 본 연구에서는 항로정보 표준의 적용방안 검토를 위해 항로생성 도구와 이를 활용한 표준기반의 항로정보 생성 및 결과를 검토 하였다. 세부 내용으로 첫째, 항로정보를 생성 할 수 있는 모듈로서 S-100 기반의 항로정보 표준에 맞게 메모리에 값을 저장할 수 있는 모듈, 둘째, 메모리에 저장한 항로정보를 xml 기반으로 저장 할 수 있는 모듈, 셋째로 xml로 저장된 항로정보의 로딩 모듈이 포함된다. 본 연구에서는 3개의 모듈 개발을 통해 항로정보의 정상적 생성여부, 생성된 항로정보의 저장 및 로딩 기능을 검증 하였다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2004년도 추계학술대회 및 정기총회
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• pp.389-392
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• 2004

The column generation process for the set-partitioning model of the vehicle routing problem requires repeated solutions of column generation subproblems which has a combinatorial structure similar to that of the traveling salesman problem. This limits the size of the problem that can be addressed. We introduce a new modeling approach, termed route-splitting, which splits each vehicle route into segments, and results in more tractable subproblems. A lower bounding scheme that yields an updated bound at each iteration of the column generation process is developed. Implementation issues, including a technique of controlling columns in the master problem, are explored. Lower bounds are computed on standard benchmark problems with up to 199 customers.

• 산업경영시스템학회지
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• 제24권65호
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• pp.89-102
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• 2001

In this paper, the aircraft route scheduling consists of two steps; the pairing generation and the aircraft assignment. The pairing generation is heuristic approach how flights construct pairings from and to the main base. The aircraft resource assignment which is to establish a aircraft route schedule is constructed by constraint satisfaction problem technique. ILOG solver and schedule is used to solve this problem. In addition, a aircraft route reschedule process against departure-arrival delay or aircraft maintenance schedule change is added by partial constraints satisfaction problem technique. Also, Gantt chart made by ILOG views is used to show aircraft route schedule results more easily.

• 제어로봇시스템학회논문지
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• 제3권2호
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• pp.156-161
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• 1997

In this thesis, based on Genetic Algorithm, a new route search algorithm is presented to search an optimal route between the origin and the destination in intelligent route guidance systems in order to minimize the route traveling time. The proposed algorithm is effectively employed to complex road networks which have diverse turn constrains, time-delay constraints due to cross signals, and stochastic traffic volume. The algorithm is also shown to significantly promote search efficiency by changing the population size of path individuals that exist in each generation through the concept of age and lifetime to each path individual. A virtual road-traffic network with various turn constraints and traffic volume is simulated, where the suggested algorithm promptly produces not only an optimal route to minimize the route cost but also the estimated travel time for any pair of the origin and the destination, while effectively avoiding turn constraints and traffic jam.

• 한국항해항만학회지
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• 제39권4호
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• pp.361-370
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• 2015

풍력에너지는 20여년 전부터 새로운 대체 연료로서 주목받기 시작하여 현재는 글로벌 비즈니스 모델로 성장하고 있다. 전 세계적으로 풍력발전이 차지하는 비율은 전체 발전량의 30%를 차지하며, 이 비율은 지난 10여 년 간 꾸준히 증가해 왔다. 근래에 들어 일반 발전방식들의 탄소 배출량 증가 및 온실효과로 인한 환경문제 등으로 인해 풍력발전에 대한 국제적 수요는 점차 커져가고 있다. 본 연구에서는 이러한 풍력 발전용 부품에 대한 효율적인 운송경로를 제안하기 위해 풍력 발전용 부품의 운송 특성에 따라 그 경로를 접근성 우선 경로, 경제성 우선 경로, 편의성 우선 경로 등으로 분류하였다. 본 연구를 통해 풍력발전부품 제조업체들은 제품의 운송기간의 문제 뿐 아니라 운송경로의 효율성과 경제성까지 판단할 수 있게 되었다. 즉 지금까지 선박회사나 포워더를 통해 이루어지던 운송경로의 결정을 제조업체도 해당 운송경로의 효율성과 경제성을 분석하고 비교할 수 있게 되었다.

• 경영정보학연구
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• 제10권1호
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• pp.115-133
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• 2008

3자 물류 업계는 주로 화주를 대신하여 화물을 출발지에서 도착지까지 전달해주는 업무를 담당하고 있으며, 이를 위해서는 출발지와 도착지간의 운송 수단, 출발/도착 스케줄, 그리고 운임 등에 대한 정보를 필요로 한다. 또한 복합운송은 다양한 수송수단을 서로 조화롭게 통제하여 마치 하나의 수송수단을 이용하는 것처럼 자연스럽게 운영되어야 하는데, 이를 위해서는 스케줄 정보 수집과 이를 통해 가능한 수송경로를 생성할 수 있는 시스템을 구축할 필요가 있다. 하지만 현재 물류업체에서는 체계적인 시스템의 부재로 인해 충분하고 객관적인 정보를 바탕으로 서비스를 제공하지 못하고 있다. 대부분 담당자의 경험을 통하여 수작업으로 수송경로를 계획하고 있어, 거래량 및 물량이 늘어날수록 수작업에 의한 작업은 한계를 보이고 있다. 복합운송에서 최적 수송경로 생성과 선정을 어렵게 하는 이유는 크게 두 가지로 볼 수 있다. 첫째는 수송경로를 선정하기 위한 운송수단 별 스케줄 데이터 확보의 어려움이다. 두 번째는 수많은 스케줄 자료를 바탕으로 가능한 수송경로를 생성하고, 이들 중 고객의 요구에 가장 적합한 경로를 찾아내는 방법 개발에 대한 어려움이다. 이에 본 연구에서는 웹을 통해 제공되고 있는 스케줄 정보를 능동적으로 탐색 및 식별하여 실시간으로 수집할 수 있는 방법과 복합수송 서비스를 제공하는 물류업체의 핵심적인 업무인 수송경로 생성과 선정을 지원하는 지능형 복합운송 경로 계획시스템을 개발하고자 한다.

• 한국항해항만학회지
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• 제47권2호
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• pp.66-74
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• 2023

With the increase of interest in developing Maritime Autonomous Surface Ships (MASS), an optimal ship route planning is gradually gaining popularity as one of the important subsystems for autonomy of modern marine vessels. In the present paper, an optimal ship route planning model for MASS is proposed using a nonlinear MPC approach together with a nonlinear MMG model. Results drawn from this study demonstrated that the optimization problem for the ship route was successfully solved with satisfaction of the nonlinear dynamics of the ship and all constraints for the state and manipulated variables using the nonlinear MPC approach. Given that a route generation system capable of accounting for nonlinear dynamics of the ship and equality/inequality constraints is essential for achieving fully autonomous navigation at sea, it is expected that this paper will contribute to the field of autonomous vehicles by demonstrating the performance of the proposed optimal ship route planning model.