• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2002.04a
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• pp.219-228
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• 2002

Because western sea on the shore development is threatening sea ecosystem by decrease of silt and large size land-reclamation work by industrialization causes surrounding weather change and sea change, generate much changes bottom of the sea topography and coastline. Also, is influencing to route for safe entry into port of ship, departure. Therefore, this research did 0m boundary line, anxiety 2m line which appear to coastline of land portion and the border of silt using sea base level of lowest low tone side that is base line that appear because of sea waves to basis data numerical value Tuesday, numerical value by divide drawing that is changed to 4 area and analyze change degree of new airport construction and new town development, seashore by western sea district along the coast development of tide embankment construction and so on and bottom of the sea recognize.

• Journal of the Korean Geophysical Society
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• v.5 no.3
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• pp.219-231
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• 2002

Single beam echo sounding was used to delineate bathymetry sea bottom in the area of hydrography and marine navigation. This research was aimed at measuring the thickness of floating silty clay sediment with dual frequencies echo sounding system. There occur discrepancies in penetrating depth through sea beds between high frequency(200 KHz) and low(33 KHz) frequency. RI density logging was employed to characterize the floating silty clay sediment of Guangyang bay, which was chosen to investigate the proposed site for reclamation field. The volume of floating silty clay sediment was used to design by estimating size of reclamation site. The estimation strategies developed in this study will be readily applicable to measure the Pattern of sedimentation via regular hydrographic survey in the future.

• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.4
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• pp.14-21
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• 2007

In general bathymetric surveying is the method which gets depth. The water depth on chart is generally measured by a 200Khz frequency echo-sounder. In this study the thickness of the floating silt-clay was measured by a duel frequency sounder using 33Khz and 200Khz. This study shows the method of measuring the volume of the floating silt-clay in dredged basins dredged basin. After this surveying RI test was performed for verifying the existence of the silt-clay.

• Journal of Korea Water Resources Association
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• v.56 no.spc1
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• pp.1027-1036
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• 2023

Coastal topographic information is crucial in coastal management, but point measurment based approeaches, which are labor intensive, are generally applied to land and underwater, separately. This study introduces an efficient method enabling land and undetwater surveys using an unmanned aerial vehicle (UAV). This method involves applying two different algorithms to measure the topography on land and water depth, respectively, using UAV imagery and merge them to reconstruct whole coastal digital elevation model. Acquisition of the landside terrain is achieved using the Structure-from-Motion Multi-View Stereo technique with spatial scan imagery. Independently, underwater bathymetry is retrieved by employing a depth inversion technique with a drone-acquired wave field video. After merging the two digital elevation models into a local coordinate, interpolation is performed for areas where terrain measurement is not feasible, ultimately obtaining a continuous nearshore terrain. We applied the proposed survey technique to Jangsa Beach, South Korea, and verified that detailed terrain characteristics, such as berm, can be measured. The proposed UAV-based survey method has significant efficiency in terms of time, cost, and safety compared to existing methods.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.23 no.1
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• pp.39-47
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• 2005

In this study, three-dimensional information of submarine topography acquired by assembling DGPS method and echo sounder which mainly used in the marine survey. Moreover, the hopper dredging capacity in harbor public affair has been calculated by utilizing kriging, radial basis function and nearest neighbor interpolation. Also, utilization of DGPS/Echo sounder method in calculation of the dredging capacity have been confirmed by comparing and analyzing the hopper dredging capacity and the actual one as per each interpolation. According to this comparison result, in case of applying kriging interpolation, some 1.89% of error rate has been shown as difference of the contents is 15,364 ㎥ and in case of applying radial basis function interpolation and nearest neighbor interpolation, 3.9% and 4.4% of error rates have respectively shown. In case the study for application of the proper interpolation as per characteristics of submarine topography, is preceded in calculation of the dredging capacity relevant to harbor public affairs, it is expected that more speedy and correct calculation for the dredging capacity can be made.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.2
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• pp.154-163
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• 2015

This study is based on deductions from analysis of historical changes in hydrographic surveys, the problems with the existing system in Korea and analysis of the literature, including foreign cases. Using these criteria, we created and administered a survey of marine professionals of Korea, and based on the results, established an order of priority for hydrographic surveys, as follows: changes in the seabed, quantities of marine traffic, existing performance data from hydrographic survey, consumer's demand, marine accidents, conservation of oceanic environment, and natural resources. The study also deduced, based on a survey of experts, the relative importance ranking of the major ports in South Korea and suggests policy implications and a priority decision model to conduct future hydrographic surveys in a more scientific and systematic way.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.534-539
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• 2004

The coast is important area to set up policies in aspects of environmental, international and developing of resources. The researches and surveying have been conducted by many different organizations according to their own purposes. So the fundamental researches and surveying of Korean coastal area haven't been completed. For that reason, we can't use the datum to apply for different cases. In this paper, Ive studied about our current situations and the need of surveying. For a effective research methods, we suggest dividing research areas into zones and dividing them into smaller zones, And we divide priority of research and ranging of surveying classes by grading them depending on the importance.

• 한국지구물리탐사학회:학술대회논문집
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• 2009.10a
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• pp.167-173
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• 2009

Bathymetry survey around the Baengnyeong-do was made by the Korea Hydrographic and Oceanographic Administration (KHOA), using the Simrad EM3000 Multi-Beam EchoSounder (MBES) mounted at the hull of the R/V Badaro 1. Sound velocity were monitored with frequent sound velocity profiler(SVP) casts during the acoustic measurements. The depth distribution and fluctuation of thermocline varied locally owing to the effect of several current flows such as Kuroshio current and Yellow sea coastal waters. These uncertainties cause the falling-off in accuracy of MBES results. In this paper, the bathymetry results will be presented and their accuracy will be discussed along with comparisons to the time and spatial variations in sound velocity profile.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.3
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• pp.109-114
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• 2009

Although island is great worth in ecology, environmental conservation and important territory as a national land for developing the marine, the bottom of the sea and also ecological studying field for the ages to come, it has not been managed because of lack of a scientific surveying. In the case of a cadastral record, inaccessible islands have not been registered in current cadastral record because of the limit of surveying technology in 1910. Therefore, a scientific investigation and systematic management about unregistered islands are necessary. But, a airborne laser scanning system is possible to acquire an accurate positions with digital images about inaccessible islands. Therefore, scientific detection of unregistered islands became possible. This paper presented the results of the shoreline extraction around the Heuksan island using Lidar data and the detection of unregistered islands comparing the cadastral map to the ortho-image. Also, we presented the extraction technique of unregistered islands by calculating their positions and areas. As a result, we extracted effectively 16 unregistered islands around the Heuksan island.

• Journal of Korea Multimedia Society
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• v.17 no.2
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• pp.152-159
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• 2014

Recently. utilization of remote sensing exploration and cloud computing has been extended to efficient measurement, store, and update of bathymetry map data according to cloud computing technology. In the field of real ocean, water depth measurements and measurement data management, distribution, and display equipment for the development and dissemination have generated a lot of time and cost. To improve these problems, through real-time three-dimensional display system at this location, we can determine the importance of measurement activities, and reduce the time and cost of measurement activities. Data measured from marine probe vessels and remote sensing exploration equipments and other various channels can be handled and managed. In this paper, we propose a realtime three-dimensional display system through the depth measurements from remote sensing exploration. The proposed real-time three-dimensional display system can be effectively applied in the field of measurement of the topographical survey of the land as well as bathymetry of the sea.