• Title/Summary/Keyword: Tides

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Terrestrial LiDAR Measurements and Analysis of Topographical Changes on Malipo Beach (지상 LiDAR를 이용한 만리포 해변 정밀 지형측량 및 지형 변화 분석)

  • Shim, Jae-Seol;Kim, Jin-Ah;Park, Han-San;Kim, Seon-Jeong
    • Ocean and Polar Research
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    • v.32 no.1
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    • pp.73-84
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    • 2010
  • A terrestrial LiDAR was used to acquire precise and high-resolution topographical information of Malipo beach, Korea. Terrestrial LiDAR and RTK-DGPS (VRS) were mounted on top of a survey vehicle and used to scan 20 times stop-and-go method with 250 m spacing intervals at ebb tides. In total, 7 measurements were made periodically from 2008 to 2009 and after each beach replenishment event. We carried out GIS-based 3D spatial analysis such as slope and volume calculations in order to assess topographical changes over time. In relation to beach replenishment, comparative analysis of each volume change revealed them to be similar. This result indicates that the terrestrial LiDAR measurements are accurate and can be used to analyze temporal topographical changes. In conclusion, the methodology employed in this study can be used efficiently to exercise coastal management through monitoring and analyzing beach process such as erosion and deposition.

Selection and Target-Site Mapping of Peptides Inhibiting HCV NS5B Polymerase Using Phage Display

  • Kim, Min-Soo;Park, Chan-Hee;Lee, Jong-Ho;Myung, Hee-Joon
    • Journal of Microbiology and Biotechnology
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    • v.18 no.2
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    • pp.328-333
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    • 2008
  • A series of pep tides binding to the HCV NS5B polymerase was selected from phage display peptide libraries. A conserved motif of Ser-Arg-X-Arg/Leu was identified among the selected peptides, and Pep2 (Trp-Ser-Arg-Pro-Arg-Ser-Leu) was chosen for further characterization. The binding of Pep2 to HCV NS5B in vivo was shown by a yeast two-hybrid assay and by subcellular colocalization analysis using immunofluorescence confocal microscopy. The in vitro interaction was also confirmed by GST pulldown assay. The replication of the HCV 1b subgenomic replicon was efficiently inhibited by the presence of the peptide. By using a subtractive biopanning against Pep2, the binding site of the peptide was mapped at the pocket of Pro388 to Pro391 in the thumb subdomain of the polymerase. A yeast two-hybrid analysis using Pro388Ala and Pro391Ala mutants of NS5B confirmed the binding.

Evidence of Vertical Mixing Caused by High Frequency Internal Waves along the Eastern Coast of Korea

  • Han, In-Seong;Lee, Ju;Jang, Lee-Hyun;Suh, Young-Sang;Seong, Ki-Tack
    • Fisheries and Aquatic Sciences
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    • v.11 no.1
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    • pp.41-49
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    • 2008
  • Internal waves and internal tides occur frequently along the eastern coast of Korea. During the spring-tide period in April 2003, the East Korean Warm Current (EKWC) flowed near the Korean East Coast Farming Forecast System (KECFFS; a moored oceanographic measurement system), creating a strong thermocline at the intermediate layer. Weakened stratification and well-mixed water appeared frequently around the KECFFS, with duration of approximately 1 day. The results suggest the following scenario. Baroclinic motion related to the internal tide generated high frequency internal waves around the thermocline. The breaking of those waves then created turbulence around the thermocline. After well-mixed water appeared, a current component with perpendicular direction to the EKWC appeared within the inertial period. The change in stratification around the KECFFS locally broke the geostrophic balance as a transient state. This local vertical mixing formed an ageostrophic current within the inertial period.

Satellite-detected red tide algal blooms in Korean and neighboring waters during 1999-2004

  • Ahn Yu-Hwan;Shanmugam Palanisamy
    • Proceedings of the KSRS Conference
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    • 2006.03a
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    • pp.95-100
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    • 2006
  • Measurements of ocean color from space since 1970s provided vital information with reference to physical and biogeochemical properties of the oceanic waters. The utility of these data has been explored in order to map and monitor highly toxic/or harmful algal blooms (HABs) that affected most of coastal waters throughout the world due to accelerated eutrophication from human activities and certain oceanic processes. However, the global atmospheric correction and bio-optical algorithms developed for oceanic waters were found to yield false information about the HABs in coastal waters. The present study aimed to evaluate the potential use of red tide index (RI) method, which has been developed by Ahn and Shanmugam (2005), for mapping of HABs in Korean and neighboring waters. Here we employed the SSMM to remove the atmospheric effect in the SeaWiFS image data and the achieved indices by RI method were found more appropriate in correctly identifying potential areas of the encountered HABs in Korean South Sea (KSS) and Chinese coastal waters during 1999-2004. But the existence of high absorbing and scattering materials greatly interfered with the standard OC4 algorithm which falsely identified red tides in these waters. In comparison with other methods, the RI approach for the early detection of HABs can provide state managers with accurate identification of the extent and location of these blooms as a management tool.

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MONITORING OF BAR TRANSFORMATION IN THE HAN RIVER ESTUARY USING RADARSAT/SAR IMAGES

  • Yang, Chan-Su;Han, Hee-Jeong;Park, Jin-Kyu;Ouchi, Kazuo
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.856-859
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    • 2006
  • In river with bar, the characteristics of its physical conditions have a close relationship with bar morphology. In this paper, a monitoring approach of bar transformation in the Han River Estuary is presented using RADARSAT/SAR Images. The estuary is divided into North and South Korea and its area is blocked by CCL(Civil Control Line). Satellite remote sensing, therefore, is uniquely suited to monitoring bar transformation. Based on SAR signatures for bars, bar transformation is investigated from 2000 to 2005, and monitoring of suspended-silt transportations from terrestrial runoff is tried to understand the morphology during the events of severe rain storm. SAR data did not reveal clearly the bar locations because of most of data acquisitions during high tides from 6.8 m to 9.0 m. Even though the problem, it could be said that in the estuary vegetated area and natural levees are developed well, but bars and shifted after an event like a flood. It is also showed that suspended solids such as silt transported through the estuary could contribute highly to a sedimentation environment around Incheon.

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Effects of Loess Application in Coastal Benthic Ecosystem (적조 방제용 황토살포가 연안 저서생태계에 미치는 영향)

  • Park, Chi-Hyun;Lee, Byoung-Ho
    • Journal of Environmental Science International
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    • v.15 no.11
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    • pp.1035-1043
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    • 2006
  • Large scale of fish kills by red tides has been occurred every year in coastal water fisheries of Korea. To suppress red tide spreading out over the south coastal water of the Korean Peninsula large amount of loess has been applied every year because loess is known to be effective in removing red tide organisms. Effects of loess application in ecosystem of underwater near sea shore were investigated with some physical characteristics of loess. Loess used for the red tide reduction consisted of very fine particles, of which size was mostly less than 0.1 mm. Particles of loess blocked light penetration, which is essential for the underwater ecosystem. Loess also pushed pH down by the hydrolysis activities of aluminium and iron It was found that underwater ecosystems where loess was applied near sea shore were devastated. Sea plants such as sea weeds were gone leaving only their roots. Clams and snails were dead under the loess dust blanket. And fishes were not found at all where loess has been sprayed lot long time. It was found that even if loess has some capacity to reduce red tide temporarily, loess application should be slopped to protect underwater ecosystems.

Reciprocal Relation between 'History from Below' and Archives: with Reference to the History Workshop Movement in England ('아래로부터의 역사' 서술과 기록의 상호 관계 - 영국의 역사워크숍운동을 중심으로 -)

  • Choi, Jae Hee
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.25 no.3
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    • pp.139-163
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    • 2014
  • This research aims to analyze the reciprocal relation between 'history from below' and archives and to set forth the overall tides of records management in England. For the Study, the articles published in the History Workshop Journal were analyzed. They used public records and private records such as newspapers, diaries, letters and oral records. Consequently Various kinds of community archives have recently flourished in England and endeavour is being made to expand the horizon of records management by TNA. This can be assessed as a new sort of soil for the history from below.

Methodology for Risk Assessment for Exposure to Hurricane Conditions

  • Edge, Billy L.;Jung, Kwang-Hyo
    • International Journal of Ocean System Engineering
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    • v.2 no.1
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    • pp.37-49
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    • 2012
  • An analysis of potential flooding by storm surge and wave run-up and overtopping can be used to evaluate protection afforded by the existing storm protection system. The analysis procedure can also be used to evaluate various protection alternatives for providing typhoon flood protection. To determine risk, the storm surges for both historical and hypothetical are compiled with tide conditions to represent high, slack and low water for neap, spring and mid range tides to use with the statistical procedure known as the Empirical Simulations Technique (EST). The EST uses the historic and hypothetical events to generate a large population of life-cycle databases that are used to compute mean value maximum storm surge elevation frequency relationships. The frequency-of-occurrence relationship is determined for all relevant locations along the shoreline at appropriate locations to identify the effect using the Empirical Storm Simulation (EST). To assist with understanding the process, an example is presented for a study of storm surge analysis for Freeport, Texas. This location is in the Gulf of Mexico and is subject to hurricanes and other tropical storms that approach from the Atlantic Ocean.

Contents and Item Development for Virtual Communities in Apartment - The Revitalization for Commununities Program - (아파트 단지 내 사이버 커뮤니티 콘텐츠 및 아이템 개발 - 공동체 활성화를 위한 프로그램 중심으로 -)

  • Park, Na-Rae;Kang, Soon-Joo
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2008.11a
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    • pp.344-349
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    • 2008
  • When it comes to discussing the natural behaviors of human life, defining the word "community" itself can be extremely crucial. The word "Community" can be defined as a group of interacting human beings sharing an environment. It is also the basic form for "dwelling" which can be explained as a quint essential factor in human life. Compared to the previous traditional society with strong bonding and close chemistry between neighbors, modern society with simple and monolithic apartments brought a literal extinction of what has been called as a 'relationship'. Hence, people started to take this phenomenon as a problematic issue. Also, high-rise apartments made its residents more isolated and individualistic on a growing basis. In order to aid the aggravating symptoms, there has been a wide recognition between the "dwellers" to develop and strengthen their "community". This movement in strengthening the "community" is currently on a full expansion towards the cyber space, riding the tides of a drastic improvement of the Internet. Apartment web sites today not only displays introductory level of information they also provide wider meanings of general lifestyle plus deeper content, which can enhance their community.

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Performance of a Horizontal-axis Turbine Based on the Direction of Current Flow (수평축 조류발전 로터의 유향변화에 따른 효율 고찰)

  • Jo, Chul-Hee;Park, Ro-Sik;Yim, Jin-Young;Lee, Kang-Hee
    • Journal of Ocean Engineering and Technology
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    • v.24 no.4
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    • pp.8-12
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    • 2010
  • The use of a tidal-current power system is one source of renewable energy that can minimize the environmental impact of power production and offer many other advantages compared to conventional energy sources. Unlike other energy production approaches, rate of energy production can be precisely predicted and the operational rate is very high. The performance of the rotor, which has a vital role in energy production using tidal currents, is determined by various design factors, and it should be optimized for the specific ocean environment in the field. The horizontal-axis turbine is very sensitive to the direction of flow, and flow direction changes due to rise and fall of the tides. To investigate the performance of the rotor considering the interaction problems with incidence angle of flow, a series of experiments were conducted, and a 3D CFD model was designed and analyzed by ANSYS CFX. The results and findings are summarized in the paper.