• 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.

• Proceedings of the Korea Contents Association Conference
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• 2016.05a
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• pp.325-326
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• 2016

해역과 육역을 포함하는 연안지역을 대상으로 하여 CASI-1500에 의해 취득된 항공 초분광 영상을 이용하여 토지피복분류를 행하고 이 분류결과로부터 육역과 해역의 경계를 추출하였다. 또한 현재 활용되고 있는 방법에 의하여 LiDAR 데이터로부터 해안선을 검출하였다.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2007.04a
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• pp.435-438
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• 2007

A laser scanning technique has been attracting much attention as a new technology to acquire location information. This technique might be applicable to a wide range of areas, most notably in geomatics, due to its high accuracy of location and automation of high-density data acquisition. In this study, the coastline was extracted using laser scanning. Through this laser scanning technique, efficient change detection of coast section can be ensured and also they can provide important information to be used when detecting a coast section in the future.

• 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.

• Journal of the Korea Society of Computer and Information
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• v.17 no.10
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• pp.61-69
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• 2012

The population of highly prolific, predatory Asterias amurensis is growing sharply from year to year along the coastline of Korea, a nation surrounded by water on three sides. To make matters worse, the fact that Asterias amurensis devours living fish and shellfish has caused a heavy loss for fishermen involved in the aquaculture industry. What it all boils down to is the significance of technologies allowing one to recognize Asterias amurensis individuals using underwater images for the purpose of exterminating Asterias amurensis or identifying a change in the population of Asterias amurensis or the migration route of Asterias amurensis. An improved Asterias amurensis recognition method based on the morphological characteristics of Asterias amurensis was proposed in this paper. The proposed recognition method aimed at cases marked by the lack of extraction information on concaveness and convexity, which are the morphological characteristics of Asterias amurensis. Extracting all the characteristics of Asterias amurensis from images taken underwater is very difficult. In this respect, the proposed recognition is effective in terms of recognizing individuals in a diversity of Asterias amurensis images. As a result of the experiment, Our proposed method has achieved superior performance with 92.5% than other method.

• Nuclear Engineering and Technology
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• v.41 no.8
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• pp.1101-1108
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• 2009

The ocean contains around eighty elements of the periodic table and uranium is also one among them, with a uniform concentration of 3.3 ppb and a relative abundance factor of 23. With a large coastline, India has a large stake in exploiting the 4 billion tonnes of uranium locked in seawater. The development of radiation grafting techniques, which are useful in incorporating the required functional groups, has led to more efficient adsorbent preparations in various geometrical configurations. Separation based on a polymeric adsorbent is becoming an increasingly popular technique for the extraction of trace heavy metals from seawater. Radiation grafting has provided definite advantages over chemical grafting. Studies related to thermally bonded non woven porous polypropylene fiber sheet substrate characterization and parameters to incorporate specific groups such as acrylonitrile (AN) into polymer back bones have been investigated. The grafted polyacrylonitrile chains were chemically modified to convert acrylonitrile group into an amidoxime group, a chelating group responsible for heavy metal uptake from seawater/brine. The present work has been undertaken to concentrate heavy metal ions from lean solutions from constant potential sources only. A scheme was designed and developed for investigation of the recovery of heavy metal ions such as uranium and vanadium from seawater.

• Korean Journal of Remote Sensing
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• v.31 no.1
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• pp.29-38
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• 2015

The coastline influenced naturally and artificially changes dynamically. While the long-term change is influenced by the rise in the surface of the sea and the changes in water level of the rivers, the short-term change is influenced by the tide, earthquake and storm. Also, man-made thoughtless development such as construction of embankment and reclaimed land not considering erosion and deformation of coast has been causes for breaking functions of coast and damages on natural environment. In order to manage coastal environment and resources effectively, In this study is intended to analyze and predict erosion in coastal environment and changes in sedimentation quantitatively by detecting changes in coastal line from data collection for satellite images and aerial LiDAR data. The coastal line in 2007 and 2012 was extracted by manufacturing Digital Surface Model (DSM) with Aviation LiDAR materials. For the coastal line in 2009 and 2010, Normalized Difference Vegetation Index (NDVI) method was used to extract the KOMPSAT-2 image selected after considering tide level and wave height. The change rate of the coastal line is varied in line with the forms of the observation target but most of topography shows a tendency of being eroded as time goes by. Compared to the relatively monotonous beach of Taean, the gravel and rock has very complex form. Therefore, there are more errors in extraction of coastlines and the combination of transect and shoreline, which affect overall changes. Thus, we think the correction of the anomalies caused by these properties is required in the future research.

• KIPS Transactions on Software and Data Engineering
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• v.10 no.8
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• pp.311-318
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• 2021

Research has been ongoing to detect ships from offshore photographs for a variety of reasons, including maritime security, identifying international trends, and social scientific research. Due to the development of artificial intelligence, R-CNN models for object detection in photographs and images have emerged, and the performance of object detection has risen dramatically. Ship detection in offshore photographs using the R-CNN model has also begun to apply to satellite photography. However, satellite images project large areas, so various objects such as vehicles, landforms, and buildings are sometimes recognized as ships. In this paper, we propose a novel methodology to improve the performance of ship detection in satellite photographs using R-CNN series models. We separate land and sea via marker-based watershed algorithm and perform morphology operations to specify RoI one more time, then detect vessels using R-CNN family models on specific RoI to reduce typology. Using this method, we could reduce the misdetection rate by 80% compared to using only the Fast R-CNN.