• Journal of the Korean Institute of Intelligent Systems
• /
• v.22 no.3
• /
• pp.379-385
• /
• 2012

This paper developes the navigation visual aid supporting a watch officer's situation awareness and analyzes its performance test result. Developing the equipment made from composite video sensor which transfer video signal, ranger laser measurement model which search out distance, Pan/ Tilt, center control device. The developed equipment with Pan/Tilt was made from high performance video sensor and ranger laser measurement. To make a real ship test, we carried on setting the developed equipment on ship, observed a danger factor and analyzed a image, and from that we can evaluate marine environment awareness. Through this result, the developed equipment can show effective ability of the awareness of the clearer check and resolution situation when compare with the binocular.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.23 no.4
• /
• pp.445-452
• /
• 2019

Today, most detection systems used in the marine industry are the majority of devices operating in the high-power X-band bands. While most detection systems using these frequencies in the X-Band band can expect a wide range of detection performance, they are not suitable for precision detection and have the limitation that they are large and heavy. In this paper, we designed, fabricated and tested an electronic scanner capable of detecting not only the surrounding objects but also the ocean waves at a low power of less than 2W in the 17GHz frequency band of the Ku-Band. A high-performance patch array antenna and Doppler effect were utilized to obtain sufficient detection performance even at low power. As a result of the test, it was confirmed that the performance was sufficiently valuable.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.28 no.4
• /
• pp.499-506
• /
• 2022

For autonomous ships to be commercialized and be able to navigate in coastal water, they must be able to detect maritime obstacles. One of the most common obstacles seen in coastal area are the farm buoys. In this study, a maritime object detection system was developed that detects buoys using the YOLO algorithm and visualizes the distance and bearing between buoys and the ship through geometric interpretation of camera images. After training the maritime object detection model with 1,224 pictures of buoys, the precision of the model was 89.0%, the recall was 95.0%, and the F1-score was 92.0%. Camera calibration had been conducted to calculate the distance and bearing of an object away from the camera using the obtained image coordinates and Experiment A and B were designed to verify the performance of the maritime object detection system. As a result of verifying the performance of the maritime object detection system, it can be seen that the maritime object detection system is superior to radar in its short-distance detection capability, so that it can be used as a navigational aid along with the radar.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2019.11a
• /
• pp.264-264
• /
• 2019

The purpose of this paper is to establish development concepts for a novel collision avoidance system with preventing function of navigator's human error (Hu-CAS) in ship control behaviors. Hu-CAS consists of four modules: 1) collision risk assessment module to estimate collision priority between the ship and objects, 2) decision-making module to decide collision risk levels, 3) parameter estimation module needed in the ship control to avoid collisions and 4) control system to control the rudder angle and speed. Hu-CAS, proposed in this paper, can provide a novel system substitution current Autopilot and/or a CAS be teen manned vessel and Autonomous ship in a future.

• Journal of Advanced Navigation Technology
• /
• v.27 no.6
• /
• pp.877-883
• /
• 2023

For safe operation of ships and management of marine fisheries farms, the data set that extracts the boundaries of marine fisheries farms can provide information on obstacles in the vessel's navigation path in advance by examining whether it matches the fishing ground permit area. In addition, it can be used to determine whether fish farms are operating to compensate for damage caused by marine accidents, and the relevant local government can use it to manage fishing grounds. It is also highly utilized as basic data to identify obstacles for safe navigation of ships. In this study, Sentinel-2 satellite image data from the European Space Agency (ESA) was used to extract the boundaries of fish farms. From the video image, the fish farm's status data by cycle was divided into five zones: Busan-Ulsan area, Geoje-Changwon area, Goseong-Tongyeong area, and Namhae-Sacheon area. Through the image highlighting process, the farm boundary data and meta data were processed and extracted.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.19 no.1
• /
• pp.11-18
• /
• 2024

This paper presents a procedure to optimize the design of 70GHz band array antenna for automotive short range radar sensor applications using Chebyshev polynomials. SRR(: Short Range Radar) systems require a wide angle width and low Side lobe level to detect targets within close proximity while ensuring a high Field of View(FoV). The optimized antenna operates in the 76 to 81GHz frequency range, and to reduce the antenna size, we arranged 12 patches in series, achieving an SLL of 10dB, angle with of 112.5o, gain of 15.4dB and an input return loss of less than -10dB at 78GHz. In this paper, we proceed with antenna design for SRR using Chebyshev polynomials, and present an optimal design for antenna structures to be used in MRR(: Medium-Range Radar) and LRR(: Long Range Radar) applications based on this paper

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.24 no.1
• /
• pp.36-42
• /
• 2018

This paper considers the Marine Traffic Risk Assessment for fixed and moving targets, which threaten officers during a voyage. The Collision Risk Assessment Formula was calculated based on a dynamic ship domain considering the length, speed and maneuvering capability of a vessel. In particular, the Navigation Risk Assessment Model that is used to quantitatively index the effect of a ship's size, speed, etc. has been reviewed and improved using a hybrid combination of a vessel's dynamic area and the Collision Risk Assessment Formula. Accordingly, a new type of Marine Traffic Risk Assessment Model has been suggested giving consideration to the Speed Length Ratio, which was not sufficiently reflected in the existing Risk Assessment Model. The larger the Speed Length Ratio (dimensionless speed), the higher the CJ value. That is, the CJ value is presented well by the Speed Length Ratio. When the Speed Length Ratio is large, states ranging from [Caution], [Warning], [Dangerous] or [Very Dangerous] are presented from a greater distance than when the Speed Length Ratio is small. The results of this study, can be used for route and port development, including dangerous route avoidance, optimum route planning, breakwater width, bridge span, etc. as well as the development of costal navigation safety charts. This research is also applicable for the selection of optimum ship routing and the prevention of collisions for smart ships such as autonomous vessels.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.24 no.5
• /
• pp.497-503
• /
• 2018

Passenger ships and training ships have a common feature in that they serve many passengers. Thus, safe navigation is very important. During normal sailing, a ship may turn using various types of steering, including maneuvers to avoid collisions with dangerous target. When a ship turns, a heeling angle occurs. If trouble arises during sailing, a dangerous heeling angle may result or a capsizing accident. In this study, the heeling angle during turning was measured through experimentation with two training ships similar to passenger ships. These findings were compared with theoretical formulas for heeling angle when turning. We confirmed that the limit of the maximum heeling angle estimation using heeling angle formula when turning presented in IMO stability criteria. In addition, it was confirmed that the maximum estimated heeling angle can be reached by applying the result calculated in the theoretical formula 1.4 times when turning right and 1.1 times when turning left to reflect sailing speed when of rudder hard over. It is expected that this study will provide basis data for establishing safe operation standards for the prevention of dangerous heeling angles when turning.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.17 no.3
• /
• pp.247-256
• /
• 2014

Recently, camera and RADAR are used for more effective and accurate observation of the bird migration. In recent years, many researches on the bird migration using RADAR are undertaking and in active, thus causes the advent of "RADAR ornithology" as a new academic field. Due to the lack of accessibility, economic feasibility and mobility of weather RADAR, airport searching RADAR and tracking RADAR, Nowadays, a marine RADAR is widely used for a bird observation. In this paper, we deals with a study on development of a remote bird observation system using marine FMCW RADAR, which monitors, records and analyzes bird movement by RADAR image processing and target recognition technology. Also, we conduct first test and second test for availability of the developed system, and verify the system to apply in bird observation domain. Consequently, we figured problems out, and correct the problems to improve the system. The developed system can apply in other domains such as environment evaluation. In the future, the system needs to improve accuracy of statistics and to track migration route of bird.

• Journal of Navigation and Port Research
• /
• v.39 no.6
• /
• pp.451-456
• /
• 2015

This research examines the use of Cross Bearing in the Republic of Korea Navy. Specifically, this study focuses on the degrees of errors caused by the order of measuring targets and suggests a new method to determine Advice Course. It then reviews the appropriateness of the contents of Location Report that is regularly to the duty officer during a voyage in a narrow channel. Whenever a naval vessel passes through a narrow channel, many number of sailors are assigned to diverse positions in order to enhance navigational safety. Even though it is possible to easily recognize the location of a ship with helps of various kinds of navigational equipments using state-of-the-art technology, there are still several situations where sailors' efforts are indispensible for calculating the position of their ship : when the ship is damaged during an engagement with enemies and when the enemies interfere (GPS) signals. In addition, the particularity of naval vessels in which many number of crew members can be assigned to various positions supports for the suitability of the use of Cross Bearing in the Navy. This study will contribute to navigational safety of the ROK Navy and fostering junior naval officers' seamanship.