• Journal of Ocean Engineering and Technology
• /
• v.21 no.4
• /
• pp.15-20
• /
• 2007

The harbor siltation by longshore sediment transports has become a serious problem on the East Coast of Korea. A reasonable prediction of the longshore sediment rate is important to approach the siltation problem effectively. In the recently developed 1-line model, the empirical constants of the sediment transport formula, which include the absolute quantity of sediment transport rate and the spatial distribution of breaking wave height by wave deformation, are treated as calibration parameters. Since these constants should be determined by the very long-term shoreline data, the longshore sediment rates are much more reasonable values. The method was applied to Hupo Beach, which has experienced heavy siltation. The authors also discuss long-term shoreline change using aerial photos and the observed wave-induced current patterns. According to the result, the SW-direction sediment transport rate was $146,892m^3/year$, and the NE direction was $2,694,450m^3/year$ at Hupo Beach for the last 11 years. The siltation in Hupo Harbor might be affected by the NE-direction sediment transport from Hupo Beach.

• Journal of The Geomorphological Association of Korea
• /
• v.26 no.2
• /
• pp.29-38
• /
• 2019

This study tries to reveal influence of artificial structure construction on shoreline change using DSAS 4.3. Before breakwater extension at the Gungchon Port, beaches at the study area were dominated by long-term erosion and especially, severe shoreline retreat was prevailed at the Wonpyeong Beach that is opened to offshore. During 2 years after the extension leading formation of shadow zone, the Gungchon Beach was rapidly developed due to sand supply to the shadow zone and then stabilized. The shadow zone only affected the northern part of the Wonpyeong Beach, while beaches from the southern part of the Wonpyeong Beach to the Munam Beach was little affected. Beach nourishment and groin construction led beach development at the northern part of the Wonpyeong Beach, while beach erosion from the southern part of the Wonypeong Beach to the Munam Beach was caused by the groin. This study suggests that sufficient consideration before coastal structure construction should be made regardless of purposes.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.10 no.2
• /
• pp.1-10
• /
• 2007

The tendency of erosion and accretion of the coast has occurred by the wanton development of a shore so that establishing the plans of nature preservation and development according to shoreline change is in demand. In this study, six DGPS positioning are executed in the periodic interval of about 2 months to choose coastal area of Gangnung, Gangwon-do and the observation data which is post-processed about 50cm accuracies on the Gangnung regular service is compared with digital map in 1998 and digital chart in 2006. Comparing DGPS values with shoreline of digital map, we know that erosion has occurred locally around training dike placed in Gangmun harbor and in southern Namhangjin, many accretions has happened near the breakwater of Namhangjin region and partial accretion is occurring in the other area. Therefore DGPS which is an acquisition method suitable for GIS data input is in use to collect the horizontal data and it could be used effectively to measure the shoreline change of time series through the long-term continuous observation by the coastal development.

• Journal of Ocean Engineering and Technology
• /
• v.14 no.3
• /
• pp.55-60
• /
• 2000

This paper is descried the experimental results of beach process including storm surge and beach recovery. By testing different surge levels and durations, effects of these to shoreline change were evaluated. In addition of beach recovery were investigated experimentally. On the other hand, we proposed the method, which can be applicable to complex hydrograph such as storm surge by modifying equation proposed by Kriebel and Dean. Moreover, applicability of this method is verified by comparing computing result with experiments.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.1 no.1
• /
• pp.50-62
• /
• 1989

Shoreline change of Haeundae beach was predicted by one-line model considering interaction of seawalls and longshore variation of wave height . Wave deformation was calculated by combined wave refraction-diffraction model . In this shoreline change model, empirical constants and offshore sediment transport rate are treated as calibration parameters, and the calculated results are in good agreement with the observed data.

• Journal of the Korean Geographical Society
• /
• v.50 no.2
• /
• pp.147-164
• /
• 2015

This study analyzed characteristics and tendencies of seasonal change on shoreline and beach with 8 beaches at East Sea coast by topographical survey for 2 years from March 2012 to February 2013. The shorelines of East Sea coast appeared that amount of seasonal change was bigger than amount of annual change. The seasonal change tendencies between Gangwon-do and Gyeongsangbuk-do coast areas existed some regional differences. To synthesize seasonal changes on 8 beaches of East Sea coast, shoreline advance and beach deposit showed clearly in summer and shoreline retreat and beach erosion showed clearly in autumn. This result is different from tendencies of seasonal change in many mid-latitude coast areas of the world, but generally corresponds with reference studies in west coast and east coast. The major factor of beach erosion showing mostly in summer is storm wave caused by typhoon. The beach erosion by storm wave also occurred in late winter. And it assumes that the beach deposit showing mostly in autumn is result of equilibrium processes of coast area against strong erosion in summer.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
• /
• 2006.09a
• /
• pp.81-84
• /
• 2006

• The Journal of the Korea Contents Association
• /
• v.13 no.10
• /
• pp.574-583
• /
• 2013

The coastal area, which is managed by local governments, geographically, culturally and economically has been transformed into more influential space. In recent years, new type of fusion researches about coastal areas that have economic, cultural and engineering aspects, have been conducted. In this study, the multiple observations information was used to analyze change of Ilsan beach shoreline which is located in Dong-gu, Ulsan, Korea. For the shoreline analysis, we used VRS-RTK(Virtual Reference System by Real-Time Kinematic) GPS survey, aerial photograph, terrestrial LiDAR survey and fixed reference station survey. Specially fixed reference station method was suggested for shoreline observation and maintenance. In the case of Ilsan beach shoreline, according to the result of multiple observations information, coastline erosion(6~12m) appeared in medium and lower part and sedimentation(3~14m) in the upper part of coastline.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.6 no.2
• /
• pp.150-156
• /
• 1994

Shoreline change due to the littoral drift in Suyeong bay, especially the Gwanganri and Haeundae beaches, was investigated. Average monthly frequency. speed. and direction of winds blowing from between east and south for the last 15 years were analysed, and offshore significant waves were hindcasted using the JONSWAP model. Wave refractions, shoaling, and breaking weir also investigated for the calculation of littoral drift. At the Gwanganri beach major longshore transport of sands occurs from the southwest to the northeast and the shoreline seems to advance in the northeast while it recedes in the southwest. At the Haeundae beach the sands mainly move from the east to the west and the shoreline retreats in the east and advances in the west.

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