• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.148-149
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• 2005

In this study, among the precision decline main causes of sounding, I suggested the characteristics of sounding data acquired by echo sounder with increasing of turbidity For this, I acquired sounding data by inputting turbidity inducer artificially in artificial water tank. And then achieved regression analysis. Conclusion are as following : Sounding Capabilities can be divided into three ranges according to the turbidity : normal range, critical range and the range where data can not be obtained by an echo sounder

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.23 no.2
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• pp.197-203
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• 2005

Dredging and reclaiming on coast, harbor construction etc. of when construct, the interest about efficiency and accuracy of sounding by measurement condition very rise. However, there are only a few studies on the accuracy improvement concerning water depth sounding condition. In this study, among the precision decline main causes of sounding, 1 suggested the characteristics of sounding data acquired by echo sounder with increasing of turbidity and the critical turbidity range under a given transducer frequency. For this, I acquired sounding data by inputting turbidity inducer artificially in artificial water tank. And then achieved regression analysis. Conclusion are as following Sounding Capabilities can be divided into three ranges according to the turbidity . normal range, critical range and the range where data can not be obtained by an echo sounder. When the turbidity exceeds $217\~259$ NTU which was considered as critical range, depth sounding was impossible.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.18 no.4
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• pp.343-350
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• 2000

This study deals with the Definition of the Earth-volume quantity and direction of throwing down stones (Q.R.R) into the Breakwater using Real-time DGPS & Echo-Sounding method. Generally, the buoy in the center line of Breakwater has been set up so as to throw down stones in the correct area. After throwing stones down there, surveyors have been surveying the depth and direction of stones with rod and sounding lead. The method, however, is not effective because of long time and a lot of human power, in addition it is incorrect. This paper has studied on the solution of those problems using Real-time DGPS & Echo-Sounding data to calculate the earth-volume quantity, direction and depth of throwing down stones. This paper says the effective and economical methods using Real-time DGPS & Echo-Sounding data there.

• 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 Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.4
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• pp.251-257
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• 2013

Bathymetry sounding or water depth measurement is becoming more and more sophisticated with the increasing demand in accuracy, resolution and coverage in the recent years. Single beam echo sounding is still utilized to gather single line bathymetric profile in many surveys as ever, although there is an increasing demand for multi-beam echo sounding. Single beam echo sounder system acquires single line profiles of water depth as the vessel travel along the survey line. In this study, we performed single beam echo sounding with GNSS receiver for hydrographic survey at Namgang dam basin to calculate pure sediment. Unlike traditional research, we used not field reference station but NTRIP service of the reference station of DGNSS(Differential Global Navigation Satellite System) Central Office in this GNSS survey. The calculation results show that scouring volume is $603,650m^3$, sediment volume is $3,913,750m^3$ and so pure sediment volume is $3,310,100m^3$ at Namgang dam basin. And the availability of the NTRIP service of the DGNSS Central Office for echo sounding in land area has been confirmed in this study.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.2
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• pp.137-145
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• 2003

Currently, the availability of 3-D topographical survey by combination of GPS and Echo Sounder has been increased in the various field like as the construction of structure, the dredging and the reclamation in the ocean and river, and observation of topographic change in seabed or riverbed. In this case, the error of depth sounding can divide in form that is happened by combination of GPS and Echo Sounder, and form that is happened in Echo Sounder itself, In this study, in the case happen by Echo Sounder itself, analyzed error by specially about geological features of the seabed and riverbed that is specular surface of sound wave and wished to present solution way. The sounding error about the echo sounder and characteristic of estuary riverbed was found by understanding the relation of average diameter and residual error and we defined correction formula, Y=-0.00474$^{*}$In(X) -0.0045 by the regression analysis. and then we verified applicability of correction formula. As the result, if measure Preliminary investigation or pre-survey the geological features for the survey area at topographical survey of estuary riverbed, we presented the error correction formula that estimate and can correct of error by Echo Sounderer.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.9 no.1
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• pp.63-73
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• 1991

The data type of the echo sounding for the contouring of coastal chart is continuous profiles, and there are no data between the profiles. In this study, at first, the depths of the regular grid along the sounding line were interpolated by linear equation. After that the depths of the regular grid located between the profiles were interpolated by kriging. The semivariogram contributes to the weight of interpolation. After comparison with the conventional Moving Average and Kriging, it turns out that this algorithm shows merits in the field of the accuracy and computing time.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.77-82
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• 2004

This study deals with the estimation of dredged soil-quantity using DGPS＆Echo-Sounder method. In measurement of topography, surveyors have been surveying the depth with rod and sounding lead. This method, however, is not effective because of long time and a lot of human power, in addition it is incorrect. This paper has studied on the solution of those problems using DGPS＆Echo-sounder data to calculate the dredged soil-quantity. This paper says the effective and economical methods using DGPS＆Echo-Sounder data there.

• Economic and Environmental Geology
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• v.35 no.3
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• pp.273-284
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• 2002

The Gravity-Geologic Method (GGM) was implemented for bathymetric determinations in the Drake Passage, Antarctica, using global marine Free-air Gravity Anomalies (FAGA) data sets by Sandwell and Smith (1997) and local echo sounding measurements. Of the 6548 bathymetric sounding measurements, two thirds of these points were used as control depths, while the remaining values were used as checkpoints. A density contrast of 9.0 gm/㎤ was selected based on the checkpoints predictions with changes in the density contrast assumed between the seawater and ocean bottom topographic mass. Control depths from the echo soundings were used to determine regional gravity components that were removed from FAGA to estimate the gravity effects of the bathymetry. These gravity effects were converted to bathymetry by inversion. In particular, a selective merging technique was developed to effectively combine the echo sounding depths with the GGM bathymetiy to enhance high frequency components along the shipborne sounding tracklines. For the rugged bathymetry of the research area, the GGM bathymetry shows correlation coefficients (CC) of 0.91, 0.92, and 0.85 with local shipborne sounding by KORDI, GEODAS, and a global ETOPO5 model, respectively. The enhanced GGM by selective merging shows imploved CCs of 0.948 and 0.954 with GEODAS and Smith & Sandwell (1997)'s predictions with RMS differences of 449.8 and 441.3 meters. The global marine FAGA data sets and other bathymetric models ensure that the GGM can be used in conjunction with shipborne bathymetry from echo sounding to extend the coverage into the unmapped regions, which should generate better results than simply gridding the sparse data or relying upon lower resolution global data sets such as ETOPO5.

• Journal of Korean Society for Geospatial Information Science
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• v.10 no.1 s.19
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• pp.27-35
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• 2002

The dam made reservoir, a major means to overcome the problems caused by water resource's uneven supply by time and space, plays an important role, particularly, of water supply. The role of water supply will get more important, considering the usage of water resource becomes more intensive. Therefore, it is continuously required to construct new dams securing water supply and to study on effective operation plans of the dam. The size of reservoir needs to be measured according to possible supply estimation in the pre-design stage. The depth of water, at this point, should be taken. Among many ways of sounding, echo sounding has been frequently used recently. This study, therefore, presents a new way of sounding that takes less time with stronger accuracy, uniting GPS and echo sounder to apply a means of obtaining three dimensional position data. This enables the designer to escape from the conventional way of sounding in the estimation of reservoir to design and redesign a new dam.