• Journal of Navigation and Port Research
• /
• v.43 no.4
• /
• pp.237-242
• /
• 2019

Behavioral errors of the seafarers are one of the major causes of collisions and are usually corrected through education and training. To correct this behavioral error, the structure in which the behavioral error occurs needs to be identified and analyzed. For this purpose, behavior observation data were obtained through ship maneuvering simulation for collision encounters. The 9-state behavior classification frame proposed by Reason was used for the behavior observation and 50 university students were involved in the experiment. Behavioral analysis used the behavioral model of collision avoidance success and failure, which was developed from the 9-state Left-to-Right Hidden Markov modeling technique. As a result of the experiment, the difference between behaviors of success and failure of collision avoidance was clearly identified, and the linkage between 9-state behaviors, required to prevent collision, was derived.

• Journal of the Korea Society of Computer and Information
• /
• v.12 no.6
• /
• pp.229-234
• /
• 2007

In the IEEE 802.11 Wireless Local Area Networks (WLANs), network nodes experiencing collisions on the shared channel need to backoff for a random period of time. which is uniformly selected from the Contention Window (CW) This contention window is dynamically controlled by the Binary Exponential Backoff (BEB) algorithm. The BEB scheme suffers from a unfairness problem and low throughput under high traffic load. In this paper, I propose a new backoff algorithm for use with the IEEE 802.11 Distributed Coordination Function.

• Journal of Korean Society of Transportation
• /
• v.19 no.5
• /
• pp.109-117
• /
• 2001

The median encroachment accident model proposed in this paper is the first step to develop cost-effective criteria about installing facilities preventing traffic accidents by median encroachment. This model consists of expected annual number of median encroachment on roadway and conditional probability to collide with vehicles on opposite lane after encroachment. Expected encroachment number is related to traffic volume and quote from a study of Hutchinson & Kennedy(1966). The probability of vehicle collision is composed of assumed headway distribution of opposite directional vehicles (negative exponential distribution), driving time of encroaching vehicle and Gap & Gap acceptance model. By using expected accident number yielded from the presented model, it will be able to calculate the benefit of reduced accident and to analyze the cost of installing facilities. Therefore this will help develop cost-effective criteria of what, to install in the median.

• Journal of Navigation and Port Research
• /
• v.28 no.3
• /
• pp.161-167
• /
• 2004

Maritime safety and marine environmental protection are the most important topic in marine society. But, so many marine accidents have been occurred with the development of marine transportation industry. On the other side, ship is being operated under a highly dynamic environment and many factors are related with ship's collision Nowadays, the increasing tendency to the human errors of ship's collision is remarkable, and the investigation of the human errors has been heavily concentrated. This study analysed on the human errors of ship's collision related to the negligence of lookout and classified basic error type using GEMS(Generic Error Modeling System) dynamic model.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.25 no.2
• /
• pp.151-158
• /
• 2019

Wireless communication technology (WAVE) for vehicles, which is the core technology behind the next-generation intelligent transport system (C-ITS), is used to deliver information about vehicles to prevent traffic accidents and traffic situations that may arise between vehicles and infrastructure. Similar traffic issues often arise in marine scenarios. Currently, AIS is being used as a means of transmitting information such as the status of relative vessels, but research is being carried out to solve problems with AIS such as overloading by applying wireless communication technology for vehicles to the sea. In this study, a collision warning system suitable for small-sized vessels was developed based on the marine application of WAVE for vehicles verified through prior research, and the adequacy of this collision warning system was reviewed through a practical test. It is expected that this system will contribute greatly to future e-Navigation applications or self-driving ships as well as to preventing marine accidents.

• Journal of the Society of Naval Architects of Korea
• /
• v.60 no.3
• /
• pp.155-164
• /
• 2023

About 75% of vessel collision accidents are caused by human error, which causes enormous economic loss, environmental pollution, and human casualties, thus research on automatic collision avoidance of vessels is being actively conducted. In addition, vessels must comply with the COLREGs rules stipulated by IMO when performing collision avoidance with other vessels in motion. In this study, the collision risk was calculated by estimating the position and velocity of other vessels through the Probabilistic Data Association Filter (PDAF) algorithm based on RADAR sensor data. When a collision risk is detected, we propose an event-triggered Nonlinear Model Predict Control (NMPC) algorithm that geometrically creates waypoints that satisfy COLREGs and follows them. To verify the proposed algorithm, simulations through MATLAB are performed.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.28 no.2
• /
• pp.254-261
• /
• 2022

Every vessel shall proceed at a safe speed to avoid collision. Additionally, every vessel shall comply with the speed limit rules in the territorial water and internal waters of Korea. The VTS operator shall properly control the compliance of the vessel with the safe speed and speed limit rules. Safe speed under the COLREG 1972 is not explicitly stipulated in knots. However, under the Domestic law for traffic safety-specific sea areas, etc., the speed limit is specified in knots and complied with. This speed limit rule is mainly based on the 'speed made good over the ground'; however, in some places, it is based on the 'speed making way through the water'. In this paper, I analyzed marine accidents that occurred in the past 5 years and the rate of violation of speed limits. Furthermore, I reviewed safe speed under the COLREG 1972, speed limit rules under domestic and foreign laws, and cases of non-compliance with safe speed in the judgment of the Korea Maritime Safety Tribunal. Resultantly, I suggested in this paper that the speed limit rules in the domestic law must be observed by vessels to prevent marine accidents, and the rules which are stipulated in terms of 'speed making way through the water' must be revised as 'speed made good over the ground' such that the vessels can easily comply with them and the VTS operator can control the vessel properly.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2014.06a
• /
• pp.290-293
• /
• 2014

하인리히 법칙에 따르면, 하나의 대형사고는 다수의 경미한 사고나 수많은 근접한 위험상황이 발생한 위치에서 발생할 확률이 높다. 해상교통상황에서도 양 선박이 충돌 위험이 있는 상황, 즉 근접사고 상황은 해상교통관련 대형 사고를 예방하는 관점에서 중요하다. 하지만, 아직까지 이러한 근접사고 자료는 VTS데이터 접근에 어려움, 관련 전문 기법 부족 등으로 수집 분석하는데 어려움이 있었다. 이에 본 연구에서는 해상교통 근접사고를 조우하는 선박간에 시공간적으로 충돌에 근접한 상황들이 발생하여 충돌의 위험이 일정한 값 이상으로 높아진 상황으로 정의하고, 2013년도 완도VTS 관제해역 해상교통 항적데이터를 적용하여 근접사고 통계를 분석하였다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2007.12a
• /
• pp.269-271
• /
• 2007

현재 세계 각지에는 선박이 통항하는 항행수역에 해상교량이 건설되고 있다. 이와 동반하여 선박이 해상교량에 충돌하는 사고가 발생하고 있다. 우리나라에서도 2009년 인천 제2연육교의 완성과 더불어 선박이 통항하는 항행수역에 해상교량이 건설되는 경우가 많아지고 있다. 이러한 해역에 건설된 해상교량은 선박의 항행수역에 건설되기 때문에 타와 주기관의 고장 등으로 선박이 해상 교량에 충돌할 가능성이 있다. 이 연구에서는 이러한 충돌사고 예방을 위하여 외국 및 우리나라의 해상교량과 관련한 해양사고 발생 현황 및 원인에 대하여 조사하고자 한다.

• Journal of the Korean Institute of Navigation
• /
• v.5 no.1
• /
• pp.37-48
• /
• 1981

There are more damages from collision at sea because of the multiple reasons of sea conditions. For the purpose of avoiding collision at sea, Internaitonal Regulations for Preventing Collision at Sea, 1972 as an international convention is in force having the nature of international navigating law. According to the nature of the convention and the principle of legislation of the convention, not only it has the preventing nature on collision but it is a basic rules to make clear the faults of collision between vessels by the admiralty court in the developed maritime countries. Since there is no so much case law on it in this country and not to fixed the legal theory to define the faults of collision in civil law as per the above convention, the further study of the civil liability on collision based upon the above convention shall be recognized in the principle of fair of the civil law.