• 수산해양교육연구
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• 제23권4호
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• pp.642-647
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• 2011

In order to analyze the influence of floating marine debris (FMD) in the East China Sea (ECS), a sighting survey was conducted from July 1st to July 14th, 2009 navigating about 966 km using a training vessel "Kaya (1,737 ton)" of Pukyong National University. The sampled zones are divided into 5 transect by observation day during the survey days and again specified with 45 segments per unit hour on the survey routes. The results of distribution of FMD are as follows: 1. The quantities of FMD at the central China Sea(CE) and northern part of Taiwan(NT) were found as total mean of 90.8 ea/hr, 56.7 ea/hr, respectively, and also 36.8 ea/hr, western part of Kyushu district(WJ), 10.7 ea/hr, 8.0 ea/hr, western(OK1) and northern part(OK2) of Okinawa, respectively. 2. Temporal variation of FMD is represented by depicting the sinusoidal curve as shape as tide in CE and OK1. 3. The higher sea surface temperature (SST) is as likely as if Kuroshio current exists strongly, the less quantities are decreased. On the other hand, the coastal zone of ECS and near of Yellow Sea are increased by lower SST.

• 유통과학연구
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• 제18권1호
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• pp.15-26
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• 2020

Purpose: This study is to analyze the image classification using Convolution Neural Network and Transfer Learning for Jeju Island and to suggest related implications. As the biggest tourist destination in Korea, Jeju Island encounters environmental issues frequently caused by marine debris along the seaside. The ever-increasing volume of plastic waste requires multidirectional management and protection. Research design, data and methodology: In this study, the deep learning CNN algorithm was used to train a number of images from Jeju clean and polluted beaches. In the process of validating and testing pre-processed images, we attempted to explore their applicability to coastal tourism applications through probabilities of classifying images and predicting clean shores. Results: We transformed and augmented 194 small image dataset into 3,880 image data. The results of the pre-trained test set were 85%, 70% and 86%, and then its accuracy has increased through the process. We finally obtained a rapid convergence of 97.73% and 100% (20/20) in the actual training and validation sets. Conclusions: The tested algorithms are expected to implement in applications for tourism service distribution aimed at reducing coastal waste or in CCTVs as a detector or indicator for residents and tourists to protect clean beaches on Jeju Island.

• 한국해안·해양공학회논문집
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• 제31권4호
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• pp.229-239
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• 2019

산사태의 시간에 따른 전파를 모의하기 위해서 천수방정식을 사용하여 산사태 수치모형을 개발하였다. 하천 및 해양에서의 산사태에 모두 해석이 가능하도록 (b, s) 좌표로 표현된 천수방정식을 개발하였다. 산사태에서 발생하는 수치적인 불연속성을 극복하기 위해서 HLL approximate Riemann solver와 total variation diminishing (TVD) limiter를 사용한 유한체적법을 사용하였다. 댐파괴 흐름와 토석류의 각 경우에 수치해석을 수행한 결과를 해석해와 실험자료와 비교를 하였다. 그 결과 서로 유사함을 확인되었다. 본 모형을 사용하여 해상 산사태와 해저 산사태를 성공적으로 모의하였다. 해저 산사태에 비해 해상 산사태의 전파속도가 더 빠르고, 바닥경사가 급할수록 또는 거칠기가 작을수록 산사태 전파속도가 더 빨라짐을 확인하였다.

• 대한지리학회지
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• 제47권4호
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• pp.474-489
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• 2012

오경섭(1997)과 손일(2000)에 의한 지형학과 한국의 자연지리학 연구 성과에 대한 정리가 있은 후, 처음으로 한국지형학회지를 통해 2011년과 2012년에 걸쳐 지형학 각 분야 성과에 대한 정리가 있었다. 이 논문은 이들 연구 성과를 종합하여 지형학과 토양학 분야에서 이루어 놓은 성과를 정확히 소개하고자 하는 데 연구의 목적이 있다. 2000년 이후 특히 주목할 만한 성과는 우리나라의 전통적인 산지체계와 서양의 근대적 산맥론과 관련된 수년간에 걸친 논쟁을 통해 뚜렷한 성과는 없었지만 학계에만 머물던 지형학이 대중매체에게 알려졌다는 것이며, 둘째는 사회적 수요를 반영하여 해안 지역의 구조물과 해안도로 등의 개발과 이에 따른 해안지형의 변화가 주요한 주제가 되고 있으며, 해안사구를 비롯한 해안퇴적 지형의 연구 성과가 크다는 점이다. 기후변화로 인한 자연재해의 증가는 산사태와 같은 방재지형학적 연구의 필요성을 증대시키고 있고, 제주도의 지질공원 지정에 따른 지오투어리즘 분야의 연구 성과가 주목할 만하다. 최근 한국의 연구 성과가 해외저널에 소개되기 시작한 점은 고무적이며, 이러한 추세는 지속될 것으로 판단된다.

• 한국해양공학회지
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• 제23권2호
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• pp.37-46
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• 2009

Typhoon Rusa in 2002 was recorded as causing the biggest damage due to flood in our country. With the enormous damage to the land, the flood was totally discharged to the open sea. As a result, in the coastal area, the discharging of a river had a big influence in comparison to the scale of the coastal area, which suffered damaged due to the discharging of the river. As it cleared the land, the load was totally discharging into the sea, where it caused various problems due to its influence on the ecosystem. These included changes to the environment, like a difference in salinity and the inflow of a land load. Therefore, in this study, a Lagrangian particle tracking model was constructed using a flow model capable of solving the behavior of a river plume, supposing Sachon Bay. It is performed the research able to tendency-like valuation and reappearance about real event. The result was that the model was well approximated the sea area tendency and the river plume of the specific event.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.444-455
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• 2009

Great concerns on geotechnical risk & hazard assessment have been increased due to human and economic damage by natural disasters with recent global climate changes. In this paper, geotechnical problems in particular, landslides which is interested in European countries and North America, were mainly discussed. For these, 18 key topics on geotechnical risk and hazards which had been discussed at the LARAM 2008 workshop in Italy were analyzed after grouping by subjects. Main topic contents consisted of applications such as field measurement, early warning systems, uncertainty analysis of parameters using radar, optical data and statistical theory and so on. And the problems related to analysis of vulnerability and deformation due to earthquakes, investigation of gas zone using seismic reflection data in a landslide area, risk quantification and hazard assessment of landslide movements and multi-dimensional analysis for stability of complex slopes were attracted. Also, there were studies on risk matters of cultural heritage, the blockglide of clayey ground, simulations of debris flows based on GIS, quantification of the failure processes of rock slopes, a meshless method for 3D crack modelling, and finally risk assessment for cryological processes due to global warming.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2007년도 정기총회 및 학술발표대회
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• pp.29-32
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• 2007

Damages induced typhoons have been increased and super-typhoons have occurred frequently. In our study, we propose a storm risk assessment technique based on CFD for the industrial structures and equipment located in the coastal regions. Inflow wind speeds are obtained through the information of geography and meteorology in considering regions before pressures of wind-environment and structures corresponding to different winds are calculated with wind speed multiplier and pressure coefficient. The results are applicable to evaluate a warning wind speed or regions vulnerable to debris in a considering region and to examine the safety of structures and their exteriors.

• 한국토양비료학회지
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• 제47권4호
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• pp.242-248
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• 2014

We have five soil series of pan soils in South Korea out of 391 series: Gangreung, Bugog, Yeongog, Jangweon, and Pogog. Productivity decreases in pan soils as pan horizons impede percolation and capillary rise of water and interrupt root extension. This study was performed to investigate pedogenic processes of pan soils mainly located in footslope and river terrace by analyzing physicochemical properties and soil micro-morphology. Korean pan soils belong to Alfisols, Ultisols, or Inceptisols and have udic or aquic soil moisture regime, mesic temperature regime, and mixed mineral substances. Texture of pan horizons selected for the present study was mainly silty clay loam with clay contents ranging from 26.3 to 45.3%. Bulk density of the pan horizons ranged from 1.4 to $2.1Mg\;m^{-3}$ and their soil structure were subangular or angular structure. In terms of micro-morphological structure, Bt horizon of Gangreung series was formed as platy and striated b-fabric structure possibly affected by uplift of coastal terrace following clay sedimentation by flood. Jangweon series showed micro-morphology of massive structure and crystallic b-fabric as macropores between coarse debris established by debris fall in slope were filled with silt-sized particles. The Bt horizons having massive structure and striated b-fabric in Yeongog, Pogog, and Bugog series implies that those horizons experienced horizontal mass flow after clay accumulation.

• 한국해양환경ㆍ에너지학회지
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• 제7권2호
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• pp.98-103
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• 2004

최근 목포-고하 대교가 목포내항을 가로질러 건설될 계획이고 목포시 인근에 남악신도시가 건설중이다. 목포항의 모습을 자연경관과 해양환경에 어울리도록 아름답게 조성하기 위하여 미항목포가꾸기 운동에 대한 시민의 관심과 참여가 필요하다. 지역시민여론에 관한 설문조사를 통하여 연안해양환경에 관한 시민의식 수준을 확인하였으며, 설문조사 결과에 기초하여 목포항과 그 주변해역의 해양환경럴전방안를 제시하였다. 해양폐기물 발생제어에 관한 지역 정책 및 해안의 해양폐기물 수거운동에 시민의 적극적 참여가 요구된다. 도시하수처리장의 운영은 효과적·효율적으로 이루어져야 하고 일반대중, 환경운동연합 혹은 민간단체에 의하여 주기적으로 감시 및 평가를 받아야 한다. 해양 환경교육프로그램의 개발과 시행 그리고 환경보전 계몽운동이 지역주민의 협조 하에서 끊임없이 이루어져야 한다. 지자체가 시민의견을 수집하고 반영하여 목포를 세계적 미항으로 꾸준히 가꾸는 경우에는 시민들이 환경보전을 위한 시민장기실천계획에 적극적으로 참여함으로써 목포항 주변의 연안해양환경은 잘 보전될 수 있을 것이다.

• 수산해양기술연구
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• 제55권4호
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• pp.372-377
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• 2019

Recently, as the global problem of marine debris and marine plastics is getting serious, various ways to solve them have been proposed, and the use of the biodegradable fishing gear is proposed as an alternative. Currently, 13 types of biodegradable fishing gears are available, but their penetration rate is only 8.7%. However, the need for the use of the biodegradable fishing gear is growing as awareness of protecting marine ecosystems is growing. Therefore, in this study, the economic effects of the expansion of biodegradable fishing gear distribution in Korea's coastal areas were analyzed through the conservation of marine ecosystems, augmentation of fisheries resources, and augmentation of fishing efficiency. According to the analysis, the economic effects of 52,795 million won, 105,590 million won, and 158,385 million won was generated as the distribution of biodegradable fishing gear were expanded to 10%, 20% and 30% across all gill net and trap.