본 연구는 연안여객선 안전관리 향상을 위해 우선적으로 개선되어야 할 요인을 도출하고, 안전관리 주체 간 인식차이를 분석 하는데 목적이 있다. 안전관리 개선 요인 발굴을 위해 전문가 그룹을 구성 후 델파이 조사를 실시하여 요인을 3개의 대분류와 10개의 중 분류로 계층화 하였다. 이후 요인 간 상대적 중요도를 평가하기 위해 점검자 그룹(해사안전감독관, 선박운항관리자)과 수검자 그룹(안전 관리책임자, 연안여객선사 관계자)으로 구분하여 설문조사를 실시하고 계층분석법(AHP)을 이용하여 분석하였다. 그 결과 점검자 그룹에 서는 대중교통수단 지정 요인이 가장 중요하게 나타났고, 수검자 그룹에서는 선원복지 지원 요인이 높게 나타났다. 계층분석법을 이용한 중요도 분석을 보완하기 위해 t-검정을 이용하여 두 그룹 간 안전관리 개선 요인에 대한 인식의 차이를 분석하였다. 그 결과 상대적 중요 도 평가결과와 대부분 일치하였으나 점검 인력 증원, 점검 인력 자격기준 강화, 운항관리 출장소 추가에 있어서는 인식의 차이가 발생하 였다. 이 연구결과는 향후 연안여객선 안전관리 제고를 위한 정책 등에 기초자료로 활용할 수 있을 것이다.

Even if only two ships are encountered, a collision may occur due to the mistaken judgment of the positional relationship. In other words, if an officer does not know a target ship’s intention, there is always a risk of collision. In this paper, the experiments are conducted to investigate how the intention affects the action of collision avoidance in cooperative and non-cooperative situations. In non-cooperative situation, each ship chooses a course that minimizes costs based on the current situation. That is, it always performs a selfish selection. In a cooperative situation, the information is exchanged with a target ship and a course is selected based on this information. Each ship uses the Distributed Stochastic Search Algorithm so that a next-intended course can be selected by a certain probability and determines the course. In the experimental method, four virtual ships are set up to analyze the action of collision avoidance. Then, using the actual AIS data of eight ships in the strait of Dover, I compared and analyzed the action of collision avoidance in cooperative and non-cooperative situations. As a result of the experiment, the ships showed smooth trajectories in the cooperative situation, but the ship in the non-cooperative situation made frequent big changes to avoid a collision. In the case of the experiment using four ships, there was no collision in the cooperative situation regardless of the size of the safety domain, but a collision occurred between the ships when the size of the safety domain increased in cases of non-cooperation. In the case of experiments using eight ships, it was found that there are optimal parameters for collision avoidance. Also, it was possible to grasp the variation of the sailing distance and the costs according to the combination of the parameters, and it was confirmed that the setting of the parameters can have a great influence on collision avoidance among ships.

During an up-righting project for a capsized ship, the dynamic effect enlarges the tensions of cables. The cable tensions which are calculated based on statics and the safety evaluation which is based on these tensions cannot ensure the safety of the up-righting project. Due to the above reasons, a numerical simulation project is applied to investigate the dynamic effect on cable tensions of up-righting projects and evaluate the safety of up-righting project in current research. Firstly, a theoretical equation of the quasi-static up-righting project model is established in current research and is solved. Subsequently, the precision of the numerical simulation method applied in current research is checked by comparing cable tensions which are calculated by theoretical model and numerical simulation method. The cable tensions in different cases are solved by the numerical simulation method which accounts for dynamic effect in order to investigate the relationship between cable tensions and capsized ship weights, cable stiffness and winding-in speed. Finally, the safety of up-righting project is evaluated based on all the cable tensions calculated. It is pointed out that cable tension increases with the value of capsized ship weight, cable stiffness or winding-in speed approximately. The safety coefficients of cable in some high winding-in speeds are bellow 1.0. The results indicate that the dynamic effect is significant and should be accounted for during the up-righting project.