• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.11 no.1
• /
• pp.56-67
• /
• 1999

It is desired to use a domestically manufactured ocean data buoy for the long-term operational ocean monitoring. The ocean data buoy manufacturing technology was introduced through the research cooperation with the Qingkong University of Taiwan. The introduced ocean data buoy system was further expanded and improved for more efficient application for the marine environmental monitoring in Korea. The size of the ocean data buoy is 2.5 m in diameter, which is smaller compared to the NOAA's 3.0 m discus buoy to allow easy land transportation and ocean deployment as well. From the dynamic response test of the buoy carried out numerically, it was shown that the measurement of waves with period greater than 4 seconds is acceptable. The measurement and control system of the data buoy were improved to increase the number of measuring parameters, to reduce power consumption and to enhance better data analysis and management. Each component of the improved data buoy system was described in detail in this paper. Water quality sensors of water temperature, salinity, DO, pH and turbidity were added to the system in addition to the marine meteorological sensors of wind speed and direction, air temperature, humidity, air pressure and wave. Inmarsat satellite communication system is used for the real-time data telemetry from the buoy deployed offshore. A field performance test of the improved and domestically manufactured buoy was carried out for a month at the open sea off Pohang together with DatawelI's Wave-rider buoy to compare the wave data. The results of the test were satisfactory.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.5 no.1
• /
• pp.51-57
• /
• 2010

This paper is to study and design a generic electronics system for a meteorological buoy. It mainly covers the communication methods of a buoy with base station, data post processing and power design of a generic weather buoy system. The experiment result shows the design is capable to works well in term of data receive from buoy at base station, battery life time and able to work standalone without any power exhausted problem.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.46 no.3
• /
• pp.186-197
• /
• 2023

In this study, we focus on the improvement of data quality transmitted from a weather buoy that guides a route of ships. The buoy has an Internet-of-Thing (IoT) including sensors to collect meteorological data and the buoy's status, and it also has a wireless communication device to send them to the central database in a ground control center and ships nearby. The time interval of data collected by the sensor is irregular, and fault data is often detected. Therefore, this study provides a framework to improve data quality using machine learning models. The normal data pattern is trained by machine learning models, and the trained models detect the fault data from the collected data set of the sensor and adjust them. For determining fault data, interquartile range (IQR) removes the value outside the outlier, and an NGBoost algorithm removes the data above the upper bound and below the lower bound. The removed data is interpolated using NGBoost or long-short term memory (LSTM) algorithm. The performance of the suggested process is evaluated by actual weather buoy data from Korea to improve the quality of 'AIR_TEMPERATURE' data by using other data from the same buoy. The performance of our proposed framework has been validated through computational experiments based on real-world data, confirming its suitability for practical applications in real-world scenarios.

• Journal of Environmental Science International
• /
• v.32 no.11
• /
• pp.841-852
• /
• 2023

In this study, the significant wave height and wave period of a specially designed observation system that connected two drifting buoys to an ocean data buoy was observed for 23 days from February 7 to 29, 2020, and the results were compared and analyzed. The results indicated that, in comparison to the ocean data buoy, the drifting buoy exhibited greater variability in significant wave height over shorter time intervals. The wave period of the ocean data buoy also appeared longer than that of the drifting buoy. The greater the observed significant wave height and wave period from both the ocean data and drifting buoys, the more pronounced the differences between the two observation instruments become. Moreover, the study revealed that the disparity in observation methods between the ocean data and drifting buoys did not significantly affect the significant wave height characteristics, as long as the period remained unchanged for up to half of the observation time.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.18 no.9
• /
• pp.2140-2146
• /
• 2014

Ocean buoys are operated for safe navigation and collecting ocean data. Recently, to reducing marine buoy's damage by ocean weather's bad condition and collision with vessels has been conducted in several field research. This paper's experiment is buoy condition monitoring about predefined data form by users. As a result using Wireless remote control board applying a radio signal processing algorithms, it can observe buoy's state at an interval of three minutes on the land. Acquired data type is changeable according to ocean weather condition or buoy's purpose of using in advance. Also, this paper conducted an experiment such as data-transmission's stability and wireless communication's availability. As results of the analysis of the transmitted data, the solar, wind and wave power indicates the maximum amount of power, 50 W, 20 W and 40 W respectively. The communication system proven through this research can apply to buoy or other ocean facility.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.6 no.2
• /
• pp.268-273
• /
• 2011

Withstanding the continuous treat from the typhoon and nasty weather from ocean, the development of the real time monitoring buoy such as ocean wave related monitoring buoy system becomes essential. In this research, the development of the ocean wave monitoring buoy system had been done domestically. The development including the data real-time monitoring (wind, temperature and pressure) added in the buoy, buoy mooring and real-time data communication system. The developed wave monitoring buoy system (drift type, wave direction and wave height type) is expected to meet the demands.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.58 no.2
• /
• pp.141-152
• /
• 2022

As a method to understand the ecological habits around the artificial reef, various reports such as fishing gear survey, diving, sound survey, underwater CCTV and camera, etc. are reported. Among them, the sound survey method is carried out by installing an acoustic system on the ship and can be investigated regardless of the marine environment such as time constraints and turbidity. Such method, however, takes a lot of manpower and time as the ship travels at a constant speed. Investigations around artificial reefs are being conducted in an artificial way, and a lot of time and labor are consumed as such. Maritime buoys have been operated for various purposes such as route signs, weather observation, marine environment monitoring and defense monitoring for navigation safety in the past, but studies on monitoring systems for ecological habits and distribution of fish using marine buoys are remarkably insufficient. Therefore, this study aims to develop a system that allows users to directly monitor fish group detector data by estimating the distribution of fish groups around artificial reefs and using wireless communication at sea. In order to confirm the suitability of the maritime buoy used in this study, it was operated to compare data using LTE-equipped buoys capable of wireless communication and a data logger-type system buoy. Data transmission of buoys capable of LTE communication was carried out in a 10-minute ON, 10-minute OFF method due to the limitation of the power supply capacity, and data of the data logger-type buoy received full data. We compared and analyzed the data received from the two fish detectors. It is expected that real-time monitoring of the wireless buoy detection device using LTE will be possible through future research.

• Journal of Ocean Engineering and Technology
• /
• v.11 no.4
• /
• pp.189-196
• /
• 1997

An oil tracking system that monitors the spilt oil trajectory by using GPS was developed. The system consists of a tracking buoy deployed on the oil spilt area and an onshore(or onboard) monitoring station. The tracking buoy is equipped with GPS, signal converter, handy radio and battery while the monitoring station includes a station radio, signal converter, antennas and PC. The hull shape of buoy is designed to effectively simulate the spilt oil movement at sea surface. Radio sets for HAM are used as a data transmitter and a data receiving station, and signal converter is also for amateur use. A field experiment was conducted and it was shown that the integrated system is relable and robust. The developed oil tracking system reveals reatively good performance at reasonable cost. In favorable environment the system may communicate in the distance more than 50km.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.8 no.3
• /
• pp.274-284
• /
• 2003

The analysis of wave parametric characteristics in sea regions in the vicinity of Korean Peninsula have been carried out using the third generation wave model, WAVEWATCH-III (Tolman, 1999) and four observed buoy data of Korea Meteorological Administration (KMA). Significant wave height increases about 2-3 hours later after the increase of wind speed. Maximum correlation coefficient between two parameters appears in Donghae buoy data, which is at off-shore region. When land breeze occurs, it can be found that the correlation coefficient decreases. Time differences between wind speeds and wave heights correspond to significant tidal periods at all of the buoy locations except for Donghae buoy. After verifying the WAVEWATCH-III model results by the comparing with observed buoy data, we have carried out numerical experiments near the Kuroshio current and East Sea areas, and then reconfirmed that when there exist an opposite strong current in the propagation direction of the waves or wind direction, wave height and length get higher and shorter, respectively and vice versa. It has been shown that these modulations of wave parameters are considerable when wind speed is week or mean current is relatively strong, and corresponding values have been represented.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.7 no.4
• /
• pp.739-749
• /
• 2015

A new conceptual dual-buoy Wave Energy Converter (WEC) for the enhancement of energy extraction efficiency is suggested. Based on actual wave data, the design process for the suggested WEC is conducted in such a way as to ensure that it is suitable in real sea. Actual wave data measured in Korea's East Sea (position: $36.404N^{\circ}$ and $129.274E^{\circ}$) from May 1, 2002 to March 29, 2005 were used as the input wave spectrum for the performance estimation of the dual-buoy WEC. The suggested WEC, a point absorber type, consists of two concentric floating circular cylinders (an inner and a hollow outer buoy). Multiple resonant frequencies in proposed WEC affect the Power Ttake-off (PTO) performance of the WEC. Based on the numerical results, several design strategies are proposed to further enhance the extraction efficiency, including intentional mismatching among the heave natural frequencies of dual buoys, the natural frequency of the internal fluid, and the peak frequency of the input wave spectrum.