• Journal of the Korean Society of Marine Environment & Safety
• /
• v.23 no.6
• /
• pp.639-645
• /
• 2017

Application Specific Messages (ASM) have been introduced by a number of international bodies, such as the International Maritime Organization (IMO), the International Telecommunication Union (ITU) and the International Association of Lighthouse Authorities (IALA), for the purpose of resolving AIS overloading issues caused by an increasing number of ships using AIS systems. ASM communication will transmit a large amount of safety-related information at sea, including meteorological information, accident reporting, and navigational warnings. Specifically, this message transaction system is expected to be actively used for communication among ships and for ship-to-shore (4S), where VHF communication through voice was standard. In order to design a user-oriented service through standardised AIS-ASM messaging in the future, the need for analysis of this seems to be quite critical. In order to reflect users' AIS-ASM communication needs, therefore, frequently-occurring marine communication messages were analysed through a questionnaire survey conducted on 57 marine officers and 50 VTS operators. Based on the survey results, a list of key standardised messages was suggested as a reference for future AIS message development.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.11 no.4
• /
• pp.355-363
• /
• 2023

In safety assessment of a aged bridge, dynamic characteristics and displacement are directly related to the rigidity of the structural system, especially displacement is the most important factor as the physical quantity that the bridge user can directly detect. However, in order to measure the displacement of the bridge, it is difficult to install displacement sensors at the bottom of the bridge and conduct traffic blocking and loading tests, resulting in increased costs or impossible measurements depending on the bridge's environment. In this study, a method of measuring the displacement of a bridge using only accelerometers without installing displacement sensors and ambient vibration without a loading test was proposed. For the analysis of bridge dynamic characteristics and displacement using ambient vibration, the mode shape and natural frequency of the bridge were extracted using a TDD technique known to enable quick analysis with simple calculations, and the unit load displacement of the bridge was analyzed through flexibility analysis to calculate static displacement. To verify this proposed technology, an on-site test was conducted on C Bridge, and the results were compared with the measured values of the loading test and the structural analysis data. As a result, it was confirmed that the mode shape and natural frequency were 0.42 to 1.13 % error ratio, and the maximum displacement at the main span was 3.58 % error ratio. Therefore, the proposed technology can be used as a basis data for indirectly determine the safety of the bridge by comparing the amount of displacement compared to the design and analysis values by estimating the displacement of the bridge that could not be measured due to the difficulty of installing displacement sensors.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.21 no.4
• /
• pp.403-408
• /
• 2015

A text-based communication system has been developed with a communication function on AIS and display and input function on ECDIS as a way to complement voice communication. It features no linguistic error and is not affected by VHF restrictions on use and noise. The text communication system is designed to use messages for clear intentions and further improves convenience of users by using various UI through software. It works without additional hardware installation and modification and can transmit a sentence by selecting only via Message Banner Interface without keyboard input and furthermore has a advantage to enhance processing speed through its own message coding and decoding. It is determined as the most useful alternative to reduce language limitations and recognition errors of the user and solve the problem of various voice communications on VHF. In addition, it will help to prevent collisions between ships with decrease in VHF use, accurate communication and request of cooperation based on text at heavy traffic areas.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.23 no.4
• /
• pp.415-420
• /
• 2017

In this paper, an algorithm for object counting via a conveyor system using machine vision is suggested. Object counting systems using image processing have been applied in a variety of industries for such purposes as measuring floating populations and traffic volume, etc. The methods of object counting mainly used involve template matching and machine learning for detecting and tracking. However, operational time for these methods should be short for detecting objects on quickly moving conveyor belts. To provide this characteristic, this algorithm for image processing is a region-based method. In this experiment, we counted young abalone shells that are similar in shape, size and color. We applied a characteristic conveyor system that operated in one direction. It obtained information on objects in the region of interest by comparing a second frame that continuously changed according to the information obtained with reference to objects in the first region. Objects were counted if the information between the first and second images matched. This count was exact when young shells were evenly spaced without overlap and missed objects were calculated using size information when objects moved without extra space. The proposed algorithm can be applied for various object counting controls on conveyor systems.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.15 no.5
• /
• pp.71-82
• /
• 2016

Information System for rear-end collision avoidance is a unit service of C-ITS pilot project. Road environment that the number of vehicles at the same driving high-speed has a possibility that the communication delay or failure caused by heavy load of vehicle to vehicle communication. In this study, effects of the road network about a communication failure rate of information system for rear-end collision avoidance was analyzed quantitatively with micro traffic simulation. The simulation was carried out in situation that crash of two vehicles are occurred at merging area with speed limit 80km/h and information of collision is prvoided to the rear vehicle. From simulation results, it can confirm the trend of the increasing 14% of potential conflict according to 10% increasing of the communication failure rate. C-ITS service has a goal of increasing safety. The coommunication failure rate increases due to heavy load of vehicle causes a fatal result in road safety administrator position. For the success of C-ITS project, a communication system developers side should perform the effort to reduce the communication failure rate.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.12
• /
• pp.628-637
• /
• 2017

The automobile industry has developed Advanced Driver Assistance Systems (ADASs) to prevent traffic accidents and reduce the burden for drivers. One example is the Lane Keeping Assistance System (LKAS), which was developed for automotive vehicle systems for safety and better driving. The main system of the LKAS supports the driver while maintaining the vehicle within a lane. LKAS uses a radar sensor and camera sensor to collect information about the vehicle's position in the lane and send commands to the actuator to influence the lateral movement of the vehicle if necessary. Recently, vehicles equipped with LKAS have become commercially available. Test procedures for international LKAS evaluation are being discussed and developed by international committees, such as the International Organization for Standardization and United Nations Economic Commission for Europe. In Korea, an evaluation of LKASs for car safety is being planned by the Korean New Car Assessment Program. Therefore, test procedures should be developed for LKASs that are suitable for the domestic road environment while accommodating international standards. We developed a test scenario for LKASs and propose a formula for obtaining the target relative distance. To validate the methods, a series of experiments were conducted using commercially available vehicles equipped with LKAS.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.12
• /
• pp.887-895
• /
• 2018

This paper presents a braking model that can be used to design the safety distance of a train control system and a train braking system to increase the volume of traffic. For the braking model, a train set (electric multiple unit composed 6 cars) was tested. The factors that can affect the braking characteristics include the friction coefficient, braking pressure, and regenerative braking. The braking pressure was classified into service and emergency braking and reflected the characteristics of the vehicle. The external force acting on the running railway car was tested in accordance with KS R 9217, and the running resistance of the train is presented in the form of a polynomial. The dynamic behavior of the train running on a straight flat line was simulated using UM 8.3. The results were validated with experimental data, and the results were reasonable. With the validated model, a stopping distance was determined according to the initial braking speed and compared with the deceleration braking model. In addition, a safety distance for the train control system could be changed according to the frictional coefficient limits. These results are expected to be useful for analyzing the dynamic behavior of trains, and for analyzing various railway environments and improving the braking performance.

• The Korean Journal of Air & Space Law and Policy
• /
• v.26 no.2
• /
• pp.101-124
• /
• 2011

Since 1961, Aviation Act has regulated all aspects related to air transport business, aviation safety and airport. However, we are to face the new challenges that have to support air transport business more efficiently and air transportation services to the people effectively in condition of the globally competitive air transport industry. In this sense, the government proposed to devide "Aviation Act" into 'Air Transport Business Act', 'Aviation Safety Act', 'Airport Facility Act' in a timely manner. At first I am to take a look about the laws of traffic-related legislation and national laws of Japanese aviation system, and to evaluate implications. In addition, the background, the organization and the main information of the Act (Draft) will be introduced. And I would like to discuss the issues raised and suggest an alternative. In particular, the name of the Act (Draft), the specifying of airport manager operater, accounting method of airport development projects belong to the nation, the delegation of the authority and other issues are discussed to provide a starting point. In conclusion, the division of current "Aviation Act" is considered absolutely necessary. To stimulate fair competition, safety regulations and efficiency, the legislation process would be desirable in the direction of the total development of the aviation industry as well as ensuring aviation safety.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.19 no.5
• /
• pp.162-177
• /
• 2020

The perception of traffic environment based on various sensors in autonomous driving system has a direct relationship with driving safety. Recently, as the perception model based on deep neural network is used due to the development of machine learning/in-depth neural network technology, a the perception model training and high quality of a training dataset are required. However, there are several realistic difficulties to collect data on all situations that may occur in self-driving. The performance of the perception model may be deteriorated due to the difference between the overseas and domestic traffic environments, and data on bad weather where the sensors can not operate normally can not guarantee the qualitative part. Therefore, it is necessary to build a virtual road environment in the simulator rather than the actual road to collect the traning data. In this paper, a training dataset collection process is suggested by diversifying the weather, illumination, sensor position, type and counts of vehicles in the simulator environment that simulates the domestic road situation according to the domestic situation. In order to achieve better performance, the authors changed the domain of image to be closer to due diligence and diversified. And the performance evaluation was conducted on the test data collected in the actual road environment, and the performance was similar to that of the model learned only by the actual environmental data.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.11 no.2 s.23
• /
• pp.41-49
• /
• 2005

In general, the criminal responsibility of seaman should always be directly assumed by the seamen, according to the principle of self-incrimination. Therefore, the only possible countermeasures for the criminal responsibility of seamen may be to reduce the responsibility by using criminal procedures (ex. the warrant substance examination system, the review system of legality for confinement as much as possible. Another possibility is to reduce the penalty through the revision of the law. In detail, concerning the problem of fine, the maximum fine for oil spill accidents by criminal negligence is KRW 30,000,000 under the current Ocean Pollution Prevention Act, and when an oil spill occurs, the maximum fine tends to be levied regardless of the amount of the spilled oil; thus, it is judged that grading the fine according to the amount of spilled oil may be worth considering. Regarding P & I's payment of fine, contrary to general belief, it is only possible to make up the loss when P & I takes up the legal responsibility or acknowledges its payment. In order to solve the problem, it is possible to consider the option of introducing new collective insurance program or mutual aid system. Also, as seamen are not specialists in legal issues, the ship owners' association or the marine afficers' association need to develop some program through which they can receive systematic assistance from legal specialists including lawyers when they encounter any legal problems (ex. free legal aid programs for farmers and fishermen). Finally, it may be possible to establish enact new laws or revise the existing Act on Special cases Concerning the Settlement of Traffic Accidents to insert a new section on marine accidents.