• Journal of Ocean Engineering and Technology
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• v.30 no.6
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• pp.498-504
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• 2016

In this study, to predict the effect of beach nourishment at Haeundae Beach, the waves and wave-induced currents were compared before and after beach nourishment using the XBEACH model. Representative wave conditions were determined for the data observed during 2014 (KHOA). Then, the Hs,max and Hs,1/10 values, and their prevalent directions, were used in the numerical modeling input data. A variable grid system was used for the $5km{\times}2.5km$ model areas, and irregular waves based on the JONSWAP spectrum were given as incident wave conditions. In the summer season, eastward wave-induced currents were developed along the beach by the incident wave direction. Before the beach nourishment, the maximum speed around the surf zone was 1.2-1.5 m/s in the central zone of the beach, whereas the maximum speed increased to 1.4-1.6 m/s at the same areas when the currents toward Mipo Harbor were blocked as an effect of the groins after the beach nourishment. In the winter season, westward wave-induced currents were developed along the beach by the incident wave direction. After the beach nourishment, the maximum current speed increased slightly around the surf zone in the central area of the beach, and the littoral current speed decreased at the submerged breakwaters located at Dongbaek Island. As a result, after the beach nourishment, the maximum wave-induced currents increased about 10% in the surf zone of the central area of the beach.

• Journal of Ocean Engineering and Technology
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• v.2 no.1
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• pp.163-169
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• 1988

A beach nourishment method can be used as one of the beach. The beach nourishment is affected br a natural condition and an artificial condition; a natural condtion include conditions of bottom slope, diameter of bottom materials and wave, and an artificial condition include deposit position, method, diameter and quantity of the nourishing sand. To obtain and the best diameter of the nourishing sand a two-dimensional hydraulic model test, which simulates the erosional beach, has been accmplished. In this study the protection of the beach erosion can be maximized when the nourishing sand of 0.84mm in diameter, which is about 2.5-3.5 times of the natural bottom materials in diameter.

• Journal of Korea Water Resources Association
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• v.55 no.9
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• pp.669-678
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• 2022

The Haeundae beach and coast suffered synthetical dramatic changes especially in the nearshore topography by the beach nourishment project (i.e., 2013-2015). A previous study showed the rip current characteristics were changed according to the topographical change in terms of their magnitudes and likelihoods through numerical simulations using the FUNWAVE model. The magnitude and likelihood of rip currents decreased because the surfzone width decreased just after the beach nourishment. In this study, however, numerical simulations of the Haeundae rip currents were performed by using the 2017- and 2020-surveyed topographies changed for several years after the beach nourishment. From the simulation results using the topographies surveyed before and after the beach nourishment, it was found that the magnitude and likelihood of rip currents increased due to its increasing surfzone width in 2017 and 2020 and they might be increasing larger than those before the beach nourishment.

• Journal of Ocean Engineering and Technology
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• v.1 no.2
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• pp.60-66
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• 1987

The object of this study is to investigate behaviors of beach fill replenished at three coasts of different configurations by analyzing successively measured beach profiles. The main results obtained in this study are summarized as follows; 1) The amount of nourishing sand moved in the longshore direction surpasses the amount of nourishing sand transported in the cross-shore direction regardless of shapes of the coasts and types of the structures. 2) A clear correlation between displacements of shoreline and changes of sectional areas can be found soon after the placement of beach fill in the fields. This implies that the deformation of the artificial nourishment and dissipation or remaining rate of nourishing sand can be predicated by the one-line theory. 3) The patterns of sediment movements in the artificially nourished beaches are clearly found by the analysis of empirical eignfuncitions.

• Journal of Ocean Engineering and Technology
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• v.1 no.1
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• pp.84-93
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• 1987

A beach nourishment method can be used as one of the beach erosion protection methods which may keep coastal environments whithout constructing coastal structures on the HAE UN DAE beach. The beach nourishmens is affected by a natural condition and artificial condition;a natural condition includes conditions of bottom slope, diameter of bottom materials and waves, and artificial conditions include deposit position, method, diameter and quantity of the nourishing sand. It has accomplished to obtain the deposit position and the best diameter of the nourishing sand from a two-dimensional hydraulic model test, which simulates the erosional HAE UN DAE beach. In this study, the protection of the beach erosion can be maximized when the nourishing sand of 3.3mm in diameter, which is about 5.5.times of the bottom materials in diameter, is deposited layerly in front of the breaker zone which has a water depth of 4.6m.

• Journal of Ocean Engineering and Technology
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• v.31 no.1
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• pp.60-68
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• 2017

In this study, we analyzed the real time video image obtained from the video monitoring system to grasp the shoreline, beach width, and area change of Haeundae beach. The video monitoring techniques enabled continuous monitoring for a long period at a much lower cost than general survey methods. It was possible to grasp quantitative beach variation characteristics of Haeundae beach through image acquisition, rectification, and image processing of video images. According to the monitoring results, the erosion rate of Haeundae beach in spring and summer was -19.8% in 2014 and -6.7% in 2015. The erosion rate in 2016 was -6.4%, which showed that the erosion rate in spring and summer continued to decrease. In particular, the influence of the erosion at the time of typhoon CHABA was revealed to be smaller than in the past. It can be concluded that these variations were due to beach width expansion by beach nourishment and the installation of submerged breakwaters.

• KCID journal
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• v.19 no.1
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• pp.3-18
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• 2012

In recent years, as environmental problems have become great concerns among many people, th loss of beach sand has become one of the highly controversial issue. Major reasons for the beach erosion within the cases of West Coast can be classified as: 1) erosion at Unyeo, Baeksajang beaches are caused by the wave refraction according to the large-scale sand dredging, 2) erosion at Kkotji, Baeksajang, and Unyeo beaches are caused by large-scale embankment construction and the coastal road construction, and 3) erosion at Chollipo and Hakampo beaches are caused by construction of small ports. Erosion in the west coast of Korea coast beach erosion control measures, include groin, zeotube, terraced stone, jetty groin, and beach nourishment. Erosion control measures initially installed to prevent erosion showed a positive effect. However, if there is no continuous source of sand, the effect of measures is fewness.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2940-2944
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• 2015

Dredged materials for effective use in Hwasun-port pollution analysis, Ni(nickel) in excess of the standard showed that the whole point. However, according to the revised standards effective utilization exceeds the reference value, even if no anthropogenic sources Pearl ratio less than 10% of the average weight of the ecotoxicological tests have passed, and if so it can be used to beach nourishment. Therefore, the average weight ratio of pearl and ecotoxicological tests were conducted by marine environment official test method. Mud to 5.37% of the average weight ratio lower than the reference value of 10% that was investigated. Ecotoxicity test using bioluminescent bacteria relative luminescence inhibition in the 0 to 9.13% with no toxicity was determined using benthic amphipods in the control and the test sample relative to the average survival rate is 0% with no toxicity was determined. Therefore, the revised effective use meets all the criteria that can be used to beach nourishment, so that the suitability was assessed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.5
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• pp.639-650
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• 2022

In areas where large-scale sediment transport occurs, it is important to apply appropriate countermeasure method because the phenomenon tends to accelerate by time duration. Among the various countermeasure methods applied so far, beach nourishment needs to be reviewed as an erosion prevention measure because the erosion pattern is mitigated and environmentally friendly depending on the particle size. In the case of beach nourishment. a detailed review is required to determine the size, range, etc., of an appropriate particle diameter. In this study, we investigated the characteristics of the related topographic change using the change in the particle size of nourishment materials, the application of partial area, and the condition under the coexistence of waves and wind as variables because those factors are hard to be analyzed and interpreted within results and limitation of that the existing numerical models are not able to calculate and result out so that it is required that phenomenon or efforts are reviewed at the same time through physical model experiments, field monitoring and etc. So we attempt to reproduce the tendency of beach erosion and deposition and predict possible phenomena in the future using machine learning techniques for phenomena that it is not able to be interpreted by numerical models. we used the hydraulic experiment results for the training data, and the accuracy of the prediction results according to the change in the training method was simultaneously analyzed. As a result of the study it was found that topographic changes using machine learning tended to be similar to those of previous studies in short-term predictions, but we also found differences in the formation of scour and sandbars.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2015.11a
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• pp.141-143
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• 2015

본 연구는 해변의 양측에서 퇴적되고 해변 중앙에서 침식이 일어나고 있는 광안리 해수욕장에 최소 해빈폭을 최대로 하는 최적의 양빈 설계를 하고자 실시하였다. 광안리 해수욕장에 3가지 case의 양빈안을 수치 모의 시나리오로 구성하여 OneLine Shoreline Model을 적용하여 해빈폭의 시간적 변화를 모의하였으며, Cross-shore Profile Model을 적용하여 연평균 파고에 따른 전진폭과 최고 파고에 따른 침식폭을 추정하였다.