• Title/Summary/Keyword: Complex Coastline

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Assessment of Coastal Ground Water Discharge for Complex Coastlines (해안선의 형태를 고려한 지하수 해안 유출량 평가 기법)

  • Han, Su-Young;Hong, Sung-Hoon;Park, Nam-Sik
    • Journal of Korea Water Resources Association
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    • v.37 no.11
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    • pp.939-947
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    • 2004
  • Amount of ground water discharging through coastline(CGD) is small compared to the amount of river discharges. However, CGD is important for gound water development in coastal areas and for contamination of coastal waters by nutrients transported by ground water. In the previous study, a method was proposed to estimate CGD from simple data such as ground water levels at observation wells and hydraulic conductivities. In this study, the method is enhanced by taking into account complexity of coastlines. A new method is proposed to estimate average hydraulic gradient, length of coastline, and average thickness of freshwater The new method is verified against numerical solutions. It is shown that the method is able to estimate CGD from complex coastlines more accurately than the previous method.

A Study on Modification of Geographical Features Affecting Onset of Sea Breeze (지형적 특징이 해풍시작에 미치는 영향에 대한 연구)

  • 정우식;이화운
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.6
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    • pp.757-772
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    • 2003
  • We simulate the geographical effects on the onset time of sea breeze at Suyoung and Haeundae districts by using the LCM (Local Circulation Model). The following can be found out from the numerical simulation on Case I (real terrain) which considered the real geography of Busan metropolitan area. Especially, as a result of analyzing the land breeze path, it could be found along the coastline as it flows out through low land coastal area. To find out more about the effects of terrain and geography on the onset time of sea breeze, the results of numerical simulation of virtual geography are as follows. In Case II (flat terrain), to find out how the terrain slope affects the onset of sea breeze, flat land and the ocean was considered. As a result, convergence of nighttime air mass at a Suyoung area and nighttime strong wind speed phenomenon was not shown. In Case III (modified flat terrain), to find out the effects of the irregularity of coastline affecting the onset of sea breeze, numerical simulation was carried out by simplifying the complex coastline into segments of straight coastline. So land breeze system and changing process of sea breeze after sunrise at Suyoung and Haeundae was simulated almost in a similar manner. Through this we could find the effects of coastal irregularities on onset of sea breeze.

The study of masan barber's coastal line change during 100years

  • Choi, Chul-Uong;Kim, Young-Seop;Cho, Sung-Hwan
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.273-273
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    • 2002
  • Masan barber was situated in S.Korean southern central coast. And it is contributing greatly in S.korea's economy development to international trading port of Heaven's blessing that possess natural, geographical situation. Also, because there are Masan free tax area and chanwon heavy industrial complex, sachon air industrial complex etc. on back, it is important permanency in our country. Specially, because inland transport routes such as southern highway, Guma highway and national road system are developed well, the importance is very high. Masan harbor 1899.05.01 be that opened, the 1st and 2nd (central pier) was build 1938∼1944 year, and the 3rd pier was 1973∼1978 year. the 4th pier was 1974∼1983 year, 5th pier was 1984∼1988, 6th pier (west pier) was 1985∼1992 year. it was developed over 100 years. But, it did great many harbor and bay development of last 100 yens but research about coastline change and seashore reclamation is insufficient. Therefore, this research executed research about coastline change of Masan bay of last 100 years, In this study, we analyzed aerial photographs and tide data for the past 100 years using digital aerial photo analysis and GIS techniques for each 3-year interval. We abstracted beach DEM (digital elevation model) and ortho aerial photographs, and conducted a space analysis. As a result, we were able to identify changes in the area As a result, we drew 10 years cycle coastline change of Masan bay. and we can detect bay coastal line change and calculate refill rate.

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Basic Research on Revetments Development of Erosion Protection for Coastline Creation of Hydrophilic Environment by Field Observation (현장관측에 의한 친환경 해안조성을 위한 침식방지 호안공 개발에 관한 기초적 연구)

  • Lee, Jong-Seok;Han, Jae-Myung
    • Journal of Korea Water Resources Association
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    • v.41 no.10
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    • pp.983-993
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    • 2008
  • In recent times, sea level increasing caused by abnormal weather and global warming, sea-sand dredging and complex development causes various kind of erosion damages onto the coastal area in the world. The various types of erosion control and protection methods are applied but there are no signs of fruitful effectiveness. The PC concrete protection block for shore protection structure is practically installed in globally but most of structures in the present day became villainous because of bad accessability. In this study, hydrophilic revetments for control and protection of coastline erosion will be developed in order to make up for a faculty of the shore erosion protection block with better accessibility and excellent protection ability. Experimental measurements were researched to insure for the capacity and facility on reflection coefficient, overtopping volume, and overtopping height characteristics of newly developed shore erosion protection block in model tests. As the result, hydraulic model tests show much excellent than the general step block. Field tests were carried out also to verify through vegetative test on an affinity and construction work test of control-protection on coastline erosion with actual utilization. In the latter case, deposition of sand accumulation occurred in fairly short time at the established reaches and then we can be confirmed to utilize for newly developed block as the revetments for control and protection of coastline erosion.

The Application of High-resolution Land Cover and Its Effects on Near-surface Meteorological Fields in Two Different Coastal Areas (연안지역 특성에 따른 상세 토지피복도 적용 효과 및 기상장에 미치는 영향 분석)

  • Jeong, Ju-Hee;Kim, Yoo-Keun
    • Journal of Korean Society for Atmospheric Environment
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    • v.25 no.5
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    • pp.432-449
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    • 2009
  • In this study, the effects of high-resolution land cover on the simulation of near-surface meteorological fields were evaluated in two different coastal regions using Weather Research and Forecasting (WRF) model. These analyses were performed using the middle classification land cover data upgraded by the Korean Ministry of Environment (KME). For the purpose of this study, two coastal areas were selected as follows: (1) the southwestern coastal (SWC) region characterized by complex shoreline and (2) the eastern coastal (EC) region described a high mountain and a simple coastline. The result showed that the application of high-resolution land cover were found to be notably distinguished between the SWC and EC regions. The land cover improvement has contributed to generate the realistic complex coastline and the distribution of small islands in the SWC region and the expansion of urban and built-up land along the sea front in the EC region, respectively. The model study indicated that the improvement of land cover caused a temperature change on wide areas of inland and nearby sea for the SWC region, and narrow areas along the coastal line for the EC region. These temperature variations in the two regions resulted in a decrease and an increase in land-breeze and sea-breeze intensity, respectively (especially the SWC region). Interestingly, the improvement of land cover can contribute large enough to change wind distributions over the sea in coastal areas.

Analysis of Numerical Meteorological Fields due to the Detailed Surface Data in Complex Coastal Area (복잡 연안지역의 지표면 자료 상세화에 따른 수치 기상장 분석)

  • Lee, Hwa-Woon;Jeon, Won-Bae;Lee, Soon-Hwan;Choi, Hyun-Jung
    • Journal of Korean Society for Atmospheric Environment
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    • v.24 no.6
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    • pp.649-661
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    • 2008
  • The impact of the detailed surface data on regional meteorological fields in complex coastal area is studied using RAMS. Resolutions of topography and land use data are very important to numerical modeling, because high resolution data can reflect correct terrain height and detail characteristics of the surface. Especially, in complex coastal region such as Gwangyang area, southern area in Korean Peninsula, high resolution topography and land use data are indispensable for accurate modeling results. This study investigated the effect of resolutions of terrain data using SRTM with 3 second resolution topography and KLU with 1 second resolution land use data. Case HR was the experiment using high resolution data, whereas Case LR used low resolution data. In Case HR, computed surface temperature was higher than Case LR along the coastline and wind speed was $1{\sim}2m/s$ weaker than Case LR. Time series of temperature and wind speed indicated great agreement with the observation data. Moreover, Case HR indicated outstanding results on statistical analysis such as regression, root mean square error, index of agreement.

Maritime Boundary Delimitation Regime for the Gulf of Tonkin Dispute and China's Position (해양경계획정제도에 대한 중국의 입장과 통킹만 사례고찰)

  • Yang, Hee-Cheol;Park, Seong-Wook;Kwon, Moon-Sang
    • Ocean and Polar Research
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    • v.26 no.4
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    • pp.669-678
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    • 2004
  • Coastal states are adopting maritime boundary delimitation as their primary maritime policy because maritime jurisdiction directly relates to vast economic interest. This becomes specially important and sensitive when complex maritime boundary issues are involved between neighboring coastal states. China has not actively carried out nor declared maritime boundary delimitation until recently with any country except Agreement between China and Viet Nam on the demarcation of the territorial water, the exclusive economic zones and the continental shelf of China and Vet Nam in the Gulf of Tonkin on 25 December 2000 (hereinafter, the Gulf of Tonkin Agreement). The principles that governs maritime boundary delimitation are to consider primarily an agreement between States concerned, however, if no agreement can be reached, all relevant circumstances are considered to achieve an equity between concerned States. Relevant circumstances are length of coastline, form of coastline, existence and position of island or islands, speciality of geology/topography, and factor of economy and deffnce. Factors which sinologists are considering in regard to continental shelf delimitation of the Yellow Sea are as follows; i) geographical factor, ii) geological factor, iii) topographical factor, iv) environment and ecological (factor, v) historic interest, and vi) social and economic interest. The 'Gulf of Tonkin Agreement' is completed by basically applying the principle of delimitation according to median line which seems that China has adopted the maritime boundary delimitation principle of 'half and half' which was the intention of chinese government. At the same time, China recognized Viet Nam's dominion and sovereign right over the partial exclusive economic zone and the continental shelf of Dao Bach Long Vi in Gulf of Tonkin. This case can be considered as an example of mutual concession or compromise in delimiting maritime boundary for states of concerned.

Numerical Simulation to Evaluate Wind Resource of Korea (풍력자원 평가를 위한 한반도 수치바람모의)

  • Lee, Hwa-Woon;Kim, Dong-Hyeuk;Kim, Min-Jung;Lee, Soon-Hwan;Park, Soon-Young;Kim, Hyun-Goo
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.300-302
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    • 2008
  • For the evaluation of wind resources, numerical simulation was carried out as a tool for establishing wind map around the korean peninsula. Initial and boundary condition are given by 3 hourly RDAPS(Regional Data Assimilation and Prediction System) data of KMA(Korea Meteorology Administration) and high resolution terrain elevation land cover(30 seconds) data from USGS(United States Geological Survey). Furthermore, Data assimilation was adopted to improve initial meteorological data with buoy and QuikSCAT seawinds data. The simulation was performed from 2003 to 2006 year. To understand wind data correctly in complex terrain as the korean peninsula, at this research, Wind map was classified 4 categories by distance from coastline and elevation.

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Study on planetary boundary layer schemes suitable for simulation of sea surface wind in the southeastern coastal area, Korea (한반도 남동해안 해상풍 모의에 적합한 경계층 물리방안 연구)

  • Kim Yoo-Keun;Jeong Ju-Hee;Bae Joo-Hyun;Song Sang-Keun;Seo Jang-Won
    • Journal of Environmental Science International
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    • v.14 no.11
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    • pp.1015-1026
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    • 2005
  • The southeastern coastal area of the Korean peninsula has a complex terrain including an irregular coastline and moderately high mountains. This implies that mesoscale circulations such as mountain-valley breeze and land-sea breeze can play an important role in wind field and ocean forcing. In this study, to improve the accuracy of complex coastal rind field(surface wind and sea surface wind), we carried out the sensitivity experiments based on PBL schemes in PSU/NCAR Mesoscale Model (MM5), which is being used in the operational system at Korea Meteorological Administration. Four widely used PBL parameterization schemes in sensitivity experiments were chosen: Medium-Range Forecast (MRF), High-resolution Blackadar, Eta, and Gayno-Seaman scheme. Thereafter, case(2004. 8. 26 - 8. 27) of weak-gradient flows was simulated, and the time series and the vertical profiles of the simulated wind speed and wind direction were compared with those of hourly surface observations (AWS, BUOY) and QuikSCAT data. In the simulated results, the strength of rind speed of all schemes was overestimated in complex coastal regions, while that of about four different schemes was underestimated in islands and over the sea. Sea surface wind using the Eta scheme showed the highest wind speed over the sea and its distribution was similar to the observational data. Horizontal distribution of the simulated wind direction was very similar to that of real observational data in case of all schemes. Simulated and observed vertical distribution of wind field was also similar under boundary layer(about 1 km), however the simulated wind speed was underestimated in upper layer.

Ground Subsidence Measurements of Noksan National Industrial Complex using C-band Multi-temporal SAR images (C-밴드 다중시기 SAR 위성 영상을 이용한 녹산국가산업단지 일대의 지반침하 관측)

  • Cho, Minji;Lee, Chang-Wook
    • Korean Journal of Remote Sensing
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    • v.30 no.2
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    • pp.161-172
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    • 2014
  • Established in the lower reaches of the Nakdong river in Busan, the Noksan national industrial complex is one of the deepest soft ground areas in Korea. In case of the costal landfill having deep soft ground, there is a significant residual settlement over a long period of time. In this study, there was observed ground subsidence occurred in the Noksan national industrial complex from September 2002 to April 2007 by applying DInSAR and SBAS time series method using RADARSAT-1 and Envisat SAR datasets. As a result, it was calculated that ground subsidence developed at the velocity of about maximum 10 cm/yr and mean 6 cm/yr at the eastern center, west, western center and southern area contiguous on the coastline of the study area during the period from September 2002 to April 2007. In addition, the RADARSAT-1 average displacement map has been compared with the total displacement map observed by accurate magnetic probe extensometer during the period from 2001 to 2002. Since the time series displacement has shown a linear trend mostly, we consider that continuous monitoring should be needed until the ground subsidence of the study area has been stabilized.