• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.3
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• pp.143-148
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• 2010

Changes in coastline length and land area as well as coastline attribute distribution in Anmyondo were quantified by comparing topographic map produced in 1910's with coastline survey database compiled in 2003. Numerous reclamation has simplified complicated coastline, which resulted in reducing coastline length by 58% but increasing land area by 36%. In 2003, gravel coastline was mostly dominated. Coastline of tidal barrier also reached up to 33% of overall coastline. Gravel coastline occurred dominantly at the eastern side of Anmyondo, whereas sand coastline at the western side. An application of coastline attribute to coastal erosion zone required accurate coastline data, but it was conceived that the topographic map produced in 1910's was not useful for this purpose.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.4
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• pp.169-180
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• 2019

Shorelines should be extracted with consistency because they are the reference for determining the shape of a country. Even in the same area, inconsistent minimum vertex intervals cause inconsistencies in the coastline length, making it difficult to acquire reliable primary data for national policy decisions. As the shoreline length cannot be calculated consistently for shorelines produced by determining the arbitrary distance between points below 1m, a methodology to calculate consistent shoreline length using the minimum vertex interval is proposed herein. To compare our results with the shoreline length published by KHOA(Korea Hydrographic and Oceanographic Agency) and analyze the change in shoreline length according to the minimum vertex interval, target sites was selected and the grid overlap of the shoreline was determined. Based on the comparison results, minimum grid sizes and the minimum vertex interval can be determined by deriving a polynomial function that estimates minimum grid sizes for determining consistent shoreline lengths. By comparing public shoreline lengths with generalized shoreline lengths using various grid sizes and by analyzing the characteristics of the shoreline according to vertex intervals, the minimum vertex intervals required to achieve consistent shoreline lengths could be estimated. We suggest that the minimum vertex interval methodology by quantitative evaluation of the determined grid size may be useful in calculating consistent shoreline lengths. The proposed method by minimum vertex interval determination can help derive consistent shoreline lengths and increase the reliability of national shorelines.

• Journal of Korean Society for Geospatial Information Science
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• v.24 no.4
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• pp.83-88
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• 2016

The use of consistent coastlines is an important element for the systematic management of maritime boundaries and the interests of local governments. The Hydrographic and Oceanographic Agency conducted a preliminary survey for consistent coastline production, since 2001. As a result, the length of coastline was different by year. Because of the lack of systematic management, the use of incorrect data, etc. We also changed the coastline on the sea chart to show on a digital map for realization of terrain expression method. However, there was a variation in shoreline length due to various surveying techniques and shoreline extraction methods. In this paper, the characteristics of Jeju-do coastline were analysed by using a modified divider method of fractal dimension. The accuracy of the vectorization was determined by converting the actual distance in the Public Survey Amendment for proper divider use. With 1:5,000 and 1:25,000 digital maps of Jeju-si and Seogwipo-si each fractal dimensions were calculated. Jeju-si=1.14 and Seogwipo-si=1.12 in 1: 5,000. Jeju-si=1.13 and Seogwipo-si=1.10 in 1: 25,000. Calculated fractal dimension were correlated to data from digital maps. It was considered that complexity and scale of coastlines affected. In the future coastline length statistics and minimum ratio of calculated coastline length to original length need to be determined for consistency of coastline length statistics.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4D
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• pp.561-567
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• 2008

In this study, shoreline change was analyzed by RTK-GPS and advanced airborne LiDAR survey. For extraction of coastline, first of all, tide correction was conducted at all RTK-GPS points through the comparing with the corresponding tidal height, and cross section providing coastline was produced using Autocad Civil3D program. Comparing with two results of RTK-GPS (first, 29 Aug 2007; second, 6 Oct 2007) surveys, coastline of the first result had been decreased about 21m compare with that of the second. And it was also demonstrated that the length of coastline by the first RTK-GPS was 15m shorter than that by the airborne LiDAR survey (Dec. 2006). In addition, we recoquized that the erosion appeared in the top right-hand (dock area); the sediment in the bottom left-hand (Chosun beach area) of the Haeundae beach. As a result, therefore, it was learned that artificial sand filling for beach open and natural effects such as a typhoon, current drift, wind direction gave cause for area changes and coastline.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5D
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• pp.655-662
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• 2009

The monitoring for analyzing coastline variations throughout many years is conducted in this study. Haeundae Beach is selected as a test area. We have collected RTK-GPS survey data, airborne LiDAR survey data from Sept. 2008 to 2005. We've done airborne LiDAR survey 2009 to 2006 and we would analyze coastline changes time series through interactive comparison analysis. The mean coastline distance of Haeundae shore is 1,347m (RTK-GPS) by airborne LiDAR survey (2 times). Coastline distance is decreased approximately 4.5% than mean distance in the November survey of 2008. We know right and left sides of the coastline are eroded and the center section shows us the littoral deposit of 3~7m toward sea. It turns out that the sand both sides is transported to the center section by a wave and tide and we know the coastline distance is getting smaller but the coastline width is getting longer like 2~7m.

• The Journal of the Korea Contents Association
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• v.7 no.3
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• pp.160-167
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• 2007

Due to the drastic growth of national economy and the development of overall territory, the shapes of national land and coastal areas are changing from day to day. To detect such changes in lands and coasts efficiently, as well as to establish an appropriate usage plan, it is necessary to secure a monitoring system for coastal areas based on the observation and analysis of the change in coastlines. Currently, looking at the field of producing national coastlines, the lengths of coastlines are inaccurate due to the vague definition of dividing coastline boundaries and insufficient observation data. The level of accuracy and reliability of previous data are also in the very low. This paper used aerial photographs with certain intervals to monitor the change in coastal areas of Songjeong, Haeundae, Kwanganri, Songdo and Dadaepo. The local area subjected for this research was limited to areas near Busan.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.71-76
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• 2006

우리나라 대표적인 해운대 해수욕장은 백사장의 길이가 현재 약 1,400m, 폭은 $35{\sim}45m$, 평균수심은 약 1m에 달하는 대규모 해수욕장이다. 그리고 수심이 낮고 조차가 적으며, 수온이 따뜻하여 천혜의 조건을 갖춘 한국 최대의 해수욕장으로 한해 약 1200만 명이 넘는 관광객이 찾는 대표적인 명소이기도 하다. 그러나 지난 수십 년간의 해빈 유실로 인한 해수욕장의 존립자체의 위기가 현실화되고 있다. 해수욕장의 모래유실은 다년간에 걸쳐 진행되고 있으며, 여러 요인에 의하여 해안선의 위치와 폭이 달라지고 있다. 본 논문에서는 부산지역의 해운대 해수욕장을 선정하여 실험지역에 대한 측량을 RTK 방식으로 4개월간 3회에 걸쳐 실시하였다. 측량결과 1, 2, 3차에 걸쳐 총 3.36m의 해안선 증가의 효과가 나타남을 알 수 있었다. 또한, 모래포집시설을 설치하기 전, 후를 기점으로 비교한 결과를 파악하였으며, 향후 해빈 유실의 원인과 방지대책, 그리고 해안선 추출의 모니터링 시스템에 대하여 모색하고자 한다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1D
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• pp.81-88
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• 2012

This present research was carried out by dividing two parts; field surveying and data processing, in order to analyze changed patterns of a shoreline. Firstly, the shoreline information measured by the precise GPS positioning during long duration was collected. Secondly, the algorithm for detecting an auto boundary with regards to the changed shoreline with multi-image data was developed. Then, a comparative research was conducted. Haeundae beach which is one of the most famous ones in Korea was selected as a test site. RTK-GPS surveying had been performed overall eight times from September 2005 to September 2009. The filed test by aerial Lidar was conducted twice on December 2006 and March 2009 respectively. As a result estimated from both sensors, there is a slight difference. The average length of shoreline analyzed by RTK-GPS is approximately 1,364.6 m, while one from aerial Lidar is about 1,402.5 m. In this investigation, the specific algorithm for detecting the shoreline detection was developed by Visual C++ MFC (Microsoft Foundation Class). The analysis result estimated by aerial photo and satellite image was 1,391.0 m. The level of reliability was 98.1% for auto boundary detection when it compared with real surveying data.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.3
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• pp.191-198
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• 2007

According to the survey data during the Japanese Occupation Period, the length of South Korea's coastline is about 11,542km, including the coastlines of mainland and islands. To accurately revise/renew this coastline data through site survey, it will cost great money and time. Also, various development projects such as reclamation works on public waters, constructions of ports/harbors, etc. This paper used aerial photographs, satellite image data and GPS survey data with certain intervals to monitor the change in coastal areas of Songieong, Haeundae, Kwanganri, Songdo and Dadaepo. The local area subjected for this research was limited to areas near Busan. The specific contents of this research include. Launching qualitative/time series analyses on the change of coastal areas using aerial photographs, satellite image data and RTK-GPS surveys.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.213-215
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• 2002

함평만은 길이가 171km, 최대 폭이 12km에 달하는 반폐쇄적인 만으로서, 평균조차는 315.4cm인 중조차 해 역이다. 함평만 주변은 1910년대부터 간척사업이 진행되어 해안선이 크게 달라졌으나 해제반도로 둘러싸인 해안선은 비교적 자연성을 잘 유지하고 있다. 따라서 2001년 12월에는 무안군에 인접한 35.6$\textrm{km}^2$의 갯벌이 연안습지보전지역으로 선정되었으며 현재 보전계획이 수립되고 있다. (중략)