• 한국지구과학회:학술대회논문집
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• 2010.04a
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• pp.32-33
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• 2010

달의 기조력에 의한 조석현상으로 인하여 지구의 자전속도가 늦어지고, 결과적으로 층상구조를 이루고 있는 지구의 내부는 서로 다른 각속도로 자전한다는 차등자전 개념이 최근에 도입되었다. 지구내부의 각층에서 차등자전이 일어날 경우 각층의 경계면에서는 필연적으로 마찰열과 마찰 정전기가 발생하는 바, 특히 맨틀과 외핵의 경계부분에서 발생하는 마찰전기는 방전과정에서 대규모의 자기장, 즉 지구자기장을 발생시킬 것으로 예측된다. 본 연구에서는 마찰전기를 지속적으로 발생시키는 실험 장치를 개발하고, 고감도 자기센서로 자기장의 변화를 측정하였다. 실험 결과 유의미한 자기장의 변화를 측정하였고, 지구 자기장이 차등자전으로 인한 마찰전기에 의해 발생될 수 있음을 확인하였다.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2009.04a
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• pp.49-53
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• 2009

In this study, point gravity was measured to achieve terrestrid gravity data and the gravity is important element in precise geoid modelling. Surveys the relative gravity of 56 stations on 1st level route. In addition, it calculates gravity values, analysis gravity survey results using tidal correction, drift correction, datum-free adjustment. These point gravity data could be contribute in development of precise geoid model.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2019.10a
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• pp.85-85
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• 2019

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.26 no.2
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• pp.63-81
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• 2021

In this study, we investigated the tide-induced flow patterns near the ocean outfall of the Jeju and Bomok Wastewater Treatment Plants (WTP) in Jeju Island by using measurements of Acoustic Doppler Current Meter (ADCP) and a numerical experiment with inserting passive tracer into a regional ocean model. In late spring of 2018, the ADCP measurements showed that tidal currents dominate the flow patterns as compared to the non-tidal components in the outfall regions. According to harmonic analysis, the dominant type of tides is mixed of diurnal and semi-diurnal but predominantly semidiurnal, showing stronger oscillations in the Jeju WTP than those in the Bomok WTP. The tidal currents oscillate parallel to the isobath in both regions, but the rotating direction is different each other: an anti-clockwise direction in the Jeju WTP and a clockwise in the Bomok WTP. Of particular interest is the finding that the residual current mainly flows toward the coastline across the isobath, especially at the outfall of the Bomok WTP. Our model successfully captures the features of tidal currents observed near the outfall in both regions and indicates possibly high persistent pollutant accumulation along the coasts of Bomok.

• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.467-479
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• 2023

Satellite altimeters have continuously observed sea surface height (SSH) in the global ocean for the past 30 years, providing clear evidence of the rise in global mean sea level based on observational data. Accurate altimeter-observed SSH is essential to study the spatial and temporal variability of SSH in regional seas. In this study, we used measurements from the Ieodo Ocean Research Station (IORS) and validate SSHs observed by satellite altimeters (Envisat, Jason-1, Jason-2, SARAL, Jason-3, and Sentinel-3A/B). Bias and root mean square error of SSH for each satellite ranged from 1.58 to 4.69 cm and 6.33 to 9.67 cm, respectively. As the matchup distance between satellite ground tracks and the IORS increased, the error of satellite SSHs significantly amplified. In order to validate the correction of the tide and atmospheric effect of the satellite data, the tide was estimated using harmonic analysis, and inverse barometer effect was calculated using atmospheric pressure data at the IORS. To achieve accurate tidal corrections for satellite SSH data in the seas around the Korean Peninsula, it was confirmed that improving the accuracy of tide data used in satellites is necessary.

• Journal of the Korean earth science society
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• v.27 no.1
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• pp.6-14
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• 2006

The study investigates mental models of scientifically gifted, middle school students when it comes to tides. This was done by analyzing facet of conceptual types for two contexts. We carried out two performance tasks of tide with different context. A large number of students showed different conceptual types by context. As a result of analyzing facet of conceptual types by context, there was a slight difference in content-specific facet, but a remarkable one in strategic facet. We classified four mental models about tide by configuring facets of conceptual types: (1) Tide model (2) Force model (3) Phase model (4) Hybrid model. The Tide model is scientifically accepted model, but Force model and Phase model are incorrect models, and Hybrid model is mixed model. In cases of Force model and Phase model, conceptual types concur with each other, but these types of students comprehend tides as a result of joined forces of Moon & Sun and phase change of Moon, respectively. Arranging low mental models in proportional order, Tide model (45.0%), Hybrid model (30.0%), Force model (12.5%), and Phase model (7.5%).

• Journal of Astronomy and Space Sciences
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• v.10 no.2
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• pp.189-196
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• 1993

Satellite laser ranging observation of LAGEOS II has been performed using the SLR System at Sheshan Laser Ranging Station, Shanghai Observatory. And we obtained 1,838 observational points. The observed range data is corrected by means of system delay correction using ground target observation, atmospheric refraction delay correction, offset correction, general relativistic correction and tide correction including solid tide, polar tide and ocean tide. As a result, the determined range delay mean value is 19.12m and the mean internal accuracy by means of polynomial fitting and least square method is $\pm$7cm. Corrected observational points are 1,340 and noise ratio to total observational points is 27.1%.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.212-212
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• 2021

지구온난화에 따른 가장 큰 영향 중의 하나인 해수면 상승은 인구 및 산업시설이 집중되어 있는 연안에 심각한 영향을 미칠 수 있다. 연안 저지대 범람, 하천과 지하수로의 해수 유입, 하천의 수위증가, 조석 및 퇴적물의 변화 등의 직접적 피해를 증가시키고(국립해양조사원, 2012; Nicholls, 2002; 오상명 등, 2011), 시설물의 설계고 추산 및 흐름, 파랑의 흐름에 영향을 미쳐 연안 시설물의 안정성이나 기능성에 영향을 미치는 것으로 알려지고 있다(윤종주·김상익, 2012). 기후변화에 관한 정부간 협의체(Intergovernmental Panel on Climate Change, IPCC)의 5차 보고서(2014)에 따르면, 1901~2010년 동안 전 지구 평균해수면 상승률은 1.7mm/year에 이르며, 1990년대 이후에 더 높은 해수면 상승률을 예측하였다. 우리나라의 경우, 2010년 말까지의 자료분석 결과에서 2.48mm/year의 연평균 해수면 상승률을 보여 전세계 평균상승률보다 훨씬 상회하는 것으로 보고되고 있다(정태성, 2014; 윤종주 등, 2012). 이와 같이 전 지구적 평균해수면의 변화와는 별개로 지역적 해수면 변동특성은 그 양상이 크게 다를 수 있으며, 이는 지구온난화와 같은 자연적인 요인 뿐만 아니라 지역별 다양한 인위적 요인(풍속, 기압, 연안역 개발정도 등)에 따라 지역적 해수면 상승이 크게 변화할 수 있다. 이에 본 연구에서는 국내 연안역에 분포한 조위관측소의 장기 관측자료(수위)를 이용하여 각 지역별 해수면의 상승경향을 분석하였으며, 동/서/남해안 및 제주권역은 권역별 조석특성이 현저하게 다른 특성을 보이므로 권열별로 구분하여 분석이 수행되었는데 우리나라 대부분의 관측지점에서 평균해수면이 증가하는 추세인 것으로 나타났다.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2002.08a
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• pp.177-183
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• 2002

우리나라의 서해안은 많은 도서가 산재해 있고 지형이 복잡하며 조석의 간만의 차가 크게 나타나 연안을 따른 조간대가 폭넓게 형성되어 있다. 연안해역에 대해 새만금과 시화호 같은 부영양화 환경문제나 군산지구 개발사업 같은 연안공사에 따른 퇴적물 이동 등 다양한 연구가 진행되고 있다. (중략)

• Journal of the Korean earth science society
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• v.31 no.2
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• pp.139-150
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• 2010

This study investigated the depositional environment of the area of Anmyeondo in the mid-western coast of Korea. A total of 142 surface sediments were analyzed, and leveling survey was conducted as well in 12 transects at the sandy tidal flat in the area. The surface sediments are classified into several different types (slightly gravelly Sand, Sand, slightly gravelly sandy Mud, etc.) and they show fining-distribution toward the offshore. Textural parameters are characterized by being coarse, well sorted, positively skewed in the supratidal and intertidal flat, whereas being finer, poorly sorted, negatively skewed in the subtidal flat. According to the C-M diagram, the sediment transport modes are characterized by the mixed mode of bedload and graded suspension in supratidal and intertidal flat, and by graded suspension or uniform suspension in the subtidal flat. Histogram shows a bimodal distribution in the lower subtidal flat which is indicative of two sediment transport modes.