• Title/Summary/Keyword: 延安

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Physiochemical Characteristics of Coastal Pseudo-Estuarine Environment Formed During the Summer Flood season in the South Coast of Korea (한국 남해 연안역에서 여름 홍수기에 형성된 연안 염하구 환경의 물리 -화학적 특성)

  • 임동일;엄인권;전수경;유재명;정회수
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.8 no.2
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    • pp.151-163
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    • 2003
  • In this study, we investigated the physiochemical characteristics of temporal estuarine environment formed during the summer flood season (consecutive rainy days with average 50 mm day$^{-1}$ precipitation) in the coastal area of South Sea of Korea. The freshwater from the Seomjin River was characterized by lower temperature, salinity and pH, and high concentrations of COD and nutrients. In the summer flood season, such peculiar Somejin-River freshwater was dispersed southward along the coast of Yeosubando-Dolsando-Geumodo, form-ing temporal estuarine environment (defined as "Coastal Pseudo-Estuary" in this study) throughout the entire study area (as far as 60 km from the Seomjin River mouth). Compared to the winter dry season, the DIN/DIP ratio was almost doubled (16-36) during the summer flood season. This excessive nitrate supply during the summer flood season was probably due to nitrogenous fertilizer. Distribution and behaviors of physiochemical factors in this coastal pseudo-estuarine environment were controlled not only by the runoff of the Seomjun River (physical mixing of river water with seawater) but also by the biogeochemical estuarine processes which are mostly similar to those of the river estuary.r estuary.

Exploration of Submarine Spring Along the Coastal Areas of Busan Metropolitan City (부산 인근 연안해역에서 해저 용천수 유출 탐사)

  • Lee, Yong-Woo;Khim, Boo-Keun;Kim, Sunghan
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.18 no.4
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    • pp.178-185
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    • 2013
  • We measured salinity and $^{222}Rn$ concentration to explore submarine spring along the coastal areas (Mundongri, Icheon-ri, Jukseong-ri, Daebyeon-ri, Yeonhwa-ri, and Dadae-po) including Ilkwang Bay of Busan Metropolitan City in 2009 and 2010. Before field observation, we selected the potential and possible locations of submarine spring based on the lineament distribution and rose diagram analysis. Salinity and radon concentration were measured within the 1~2 km from the coastal lines. Radon activity decreased gradually from onshore to offshore. Vertical profiles of salinity at some stations showed lateral transport of water mass characterized by low salinity. Vertical profiles of salinity in the Ilkwang Bay, which is a unique bay in the south-eastern coastal area of Busan Metropolitan City, also showed the occurrence of low salinity in the bottom seawater. Our results suggest the possible occurrence of submarine discharge of fresh groundwater in the coastal areas around Busan Metropolitan City. In the future, intensive research should be conducted for the exploration methods of submarine spring as well for the possible utility of submarine groundwater as alternative water resources.

Assessing an Economic Feasibility of Coastal Marine Ranching Project in Uluengdo (울릉도 연안바다목장사업의 경제적 타당성분석)

  • Pyo, Heedong
    • Journal of Korea Port Economic Association
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    • v.37 no.1
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    • pp.1-18
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    • 2021
  • A coastal marine ranching project in Uleungdo had been conducted for 5 years from 2013 to 2017 with investment costs of 5 billion won, for the special purpose of the deployment of artificial reefs, the release of young fishes. The paper focuses on an ex-post analysis of the economic feasibility for the project after completing the project, which is apart from a preliminary viability. For economic analysis, the economic benefits are derived from direct benefits including increasing effects of fisheries income and saving effects of harvesting costs, and indirect benefits including increasing effects of recreational fishing and preservation effects of coastal marine ecosystems while economic costs include releasing and purchasing costs of artificial reef and juvenile fish, R&D costs, maintenance costs and harvesting costs. The result shows that the project should not be accepted according to NPV=-0.125 billion won, IRR=4.5% and B/C ratio=0.98 under Scenario 1 which considers direct benefits and indirect benefits excluding the preservation values, while the project should be accepted under Scenario 2 indicating NPV=30.9 billion won, IRR=11.3% and B/C ratio=1.49 which considers the direct benefits as well as the indirect ones including the preservation values, based on 4.5% of the social rate of discount.

A Service Facilities Evaluation of Inland River Cruise Ship by Pre-Post Comparison Based on IPA Methods (IPA분석방법에 의한 내륙연안 크루즈선의 서비스시설 사전-사후 비교 평가)

  • Wang, YiJue;Zhang, YunYao;Park, Keun-Soo
    • The Journal of the Korea Contents Association
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    • v.19 no.9
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    • pp.521-534
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    • 2019
  • From the day of luxurious inland river cruise ship started in Chongqing, China, the controversy is continuous; some people think those luxurious cruise ships on inland river might reduce the experience to enjoy the scenery of the Three Gorges, while some people think, which could improve the experience. In the study, the service facilities provided by luxurious inland river cruise ship will be evaluated by Pre-Post comparison based on IPA methods. After a review of the service facilities provided by luxurious inland river cruise ship running on Three Gorges areas. The tourists who would take the trip were asked to fill an questionnaire to examine the desired service facilities performance, which represents the highest level of the service facilities of the cruise ship that is expected by customers. After the trip, they were asked again to fill another questionnaire to examine the importance of service facilities and the performance of service. Pre-Post comparison would be examined to tell whether there is any change between pre and post experience. IPA would be used to evaluate the service facilities provided by inland river cruise ship. At last, some strategic suggestions to the development of inland river cruise ship are made.

A Preliminary Study on the Establishment of Background Levels and Management Targets in the Coastal Ecosystem of Korean Peninsula Using Outlier Test (이상치 검증을 이용한 한반도 연안생태계의 배경 농도 및 관리 항목 도출에 대한 예비 연구)

  • CHIN, BYUNG SUN;HWANG, IN SEO;KIM, YOUNG NAM;KOH, BYOUNG SEOL;YOO, JEONG KYU;JUNG, HOE IN;YEO, JUNG WON;WOO, SEUNG;PARK, GYUNG SOO
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.24 no.1
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    • pp.170-186
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    • 2019
  • The marine ecosystem survey investigates and analyzes multi-parameters at various times from various sites. Therefore, it is very difficult to analyze the complex ecological data of multi-items effectively, and it is more difficult to identify the current status and diagnose the problems of ecosystem through data analysis. Therefore, this paper aims to provide an example of interpretation of complex ecological data through analysis of distribution characteristics and outliers of ecological survey data. The main contents of the study are to elucidate the background levels of coastal ecosystem parameters considering the distribution characteristics of data, and to establish ecosystem monitoring indicators and an adaptive management system for the coastal waters in Korean Peninsula. The data used in this paper are based on the coastal ecosystem survey of the National Marine Ecosystem Monitoring Program conducted by the Ministry of Oceans and Fisheries (MOF) and the Korea Marine Environment Management Corporation (KOEM), and the major citations are from year 2015 to 2017. This article is a preliminary study to establish the above processes and the final result will be derived in 2020 when the coastal ecosystem survey is completed three times along the Korean coast.

Evaluation of Carbon Storage and Economic Value in the Busan Coastal Zone (부산 연안역 탄소저장량 및 경제적 가치 평가)

  • Jeong, Se Hwa;Chung, Jin Wook;Yim, Yu Rim;Sung, Ki June
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.5
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    • pp.651-658
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    • 2022
  • To cope with climate change, studies are being conducted on natural-based solutions (NBS) that reduce carbon by utilizing ecosystems and ecological resources ultimately to achieve carbon neutrality. In this study, carbon storage and economic value evaluations were conducted of the coastal land and sea of Busan using InVEST's Carbon and Coastal Blue Carbon models, which are ecosystem service-based evaluation models. As a result, it is estimated that the amount of carbon storage per unit area is lower than that of the entire Busan land area and that if the currently underway or planned development works are completed, the carbon storage of the coastal land areas would be decreased more. Coastal sea areas have less carbon storage than coastal land, but there is great potential for NBS that utilize ecological resources in the future. If the reclamation of public water affects important habitats with high carbon storage levels, it will reduce these levels, and such negative effects could last for a long time. For the sustainable management of Busan coastal areas, ecosystem service-based management strategies are needed considering carbon storage.

Analysis of Built and Walking Environment for Coastal Ferry Terminal using IPA -Focusing on Yeosu Coastal Ferry Terminal- (IPA를 이용한 연안여객터미널의 시설 및 보행특성 분석 -여수연안여객터미널을 중심으로-)

  • Song, Tea-Han;Kim, Hwa-Young
    • Journal of Korea Port Economic Association
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    • v.37 no.3
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    • pp.93-104
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    • 2021
  • A coastal ferries, which serve as a mode between mainland and offshore islands, are frequently used by islanders and travelers visiting islands. Therefore, it is located in a place with good accessibility to the downtown so that users can use it conveniently. However, research on the built environment and walking environment of coastal ferry terminals has not been conducted to ensure that elderly islanders and general travelers can use comfortably the coastal ferry terminal. In this study, with a focus on the coastal ferry terminal space, the walking section was set as 1)the accessibility of the coastal ferry terminal, 2)the built environment for using the coastal ferry terminal, and 3)walking environment in the ferry boarding and disembarkation at the coastal ferry terminal, and 4, 5)walking environment in the ferry. An evaluation tool was developed to measure the walking environment for each walking section, and the importance and satisfaction of users were analyzed using the IPA for the Yeosu Coastal Ferry Terminal. As a result, in the process of approaching the ferry terminal, 'convenience of using public transportation by foot' and 'convenience of using signposts guiding the location and direction of the ferry terminal' were investigated as concentrated areas. On the other hand, the built environment inside the ferry terminal and the walking environment showed that the satisfaction of the users was high. Regarding the walking environment from the ferry terminal to the ferry, the 'surface walking environment of the walking path', 'convenience of walking with luggage', 'convenience of walking in the slope section', and 'convenience of walking in the ferry ramp section' showed low satisfaction. This study can be used as basic data for improving the facilities and walking environment of Yeosu Coastal Ferry Terminal and is expected to be used as data for comparative research with other coastal ferry terminals.

Evolution and Changes of Coastal Topography due to Jetty Construction at Namdae River Mouth (도류제 건설 후 남대천 하구의 해안선 생성 및 변화)

  • Kim, In Ho;Lee, Seong Dae
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.3B
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    • pp.315-321
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    • 2008
  • Recently, in the light of environments and utilization, countermeasures to preserve beaches in coastal area are required without depending on such as jetties and breakwaters. The necessity of integrated sand management including not only coastal sediment but also sediment discharge from hinterland rivers is increased so as to establish long-term counterplan for sediment transport. In this regard, the following subjects are examined in this study; efficient ways for discharged sand to be transported from a river to the neighboring coast, the river terrace occurrence and its growth at the river delta, measures to improve storage efficiency of the discharged sand and measures to prevent the sand resources from being discharged into the deep sea during flooding. In recent, A jetty of 260 m length was constructed at Namdae River mouth in the year of 2005 as a countermeasure against the occurrence of sand-bar at river mouth and its close. In this study, a series of numerical experiments were carried out to investigate the characteristics of sediment transport and morphological change due to the construction of jetty at the entrance of Namdae River mouth. Firstly, The sand discharge from Namdae River is quantified by one-dimensional numerical analysis assuming the mixed sand of three different particle diameters. Then, in order to understand the transport behavior of the sand discharge from river and river mouth phenomena the numerical experiments were then conducted to examine the flow behaviors of river efflux and wind generated circulations in coastal area. And, after establishing the numerical model system, which predicts the sea bed changes obtained from the flux model combining with the wave propagation, wave-induced currents and sediment transport models, the sediment transport in the vicinity of Namdae River mouth is analyzed.

Development of Predicting Function for Wind Wave Damage based on Disaster Statistics: Focused on East Sea and Jeju Island (재해통계기반 풍랑피해액예측함수 개발 : 동해안, 제주를 중심으로)

  • Choo, Tai-Ho;Kwon, Jae-Wook;Yun, Gwan-Seon;Yang, Da-Un;Kwak, Kil-Sin
    • Journal of the Korean Society for Environmental Technology
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    • v.18 no.2
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    • pp.165-172
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    • 2017
  • In current stage, it is hard to predict the scale of damage caused by natural disaster and it is hard to deal with it. However, in case of disaster planning level, if it is possible to predict the scale of disaster then quick reaction can be done which will reduce the damage. In the present study, therefore, function of wind wave damage estimation among various disaster is developed. Damage of wind wave and typhoon in eastern and Jeju coastal zone was collected from disaster report (1991~2014) published by Ministry of Public Safety and Security and to reflect inflation rate, 2014 damage cost was converted. Also, wave height, wind speed, wave direction, wave period, etc was collected from Meteorological Administration and Korea Hydrographic and Oceanographic Administration web site. To reflect the characteristic of coastal zone when wave damage occurs, CODI(Coastal Disaster Index), COSI(Coastal Sensitivity Index), CPII(Coastal Potential Impact Index) published by Korea Hydrographic and Oceanographic Agency in 2015 were used. When damage occurs, function predicting wind wave damage was developed through weather condition, regional characteristic index and correlation of damage cost.

A study on the development of a ship-handling simulation system based on actual maritime traffic conditions (선박조종 시뮬레이터를 이용한 연안 해역 디지털 트윈 구축에 연구)

  • Eunkyu Lee;Jae-Seok Han;Kwang-Hyun Ko;Eunbi Park;Kyunghun Park;Seong-Phil Ann
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2023.05a
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    • pp.200-201
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    • 2023
  • Digital twin technology is used in various fields as a method of creating a virtual world to minimize the cost of solving problems in the real world, and is also actively used in the maritime field, such as large-scale systems such as ships and offshore plants. In this paper, we tried to build a digital twin of coastal waters using a ship-handling simulator. The digital twin of the coastal waters developed in this way can be used to safely manage Korea's coastal waters, where maritime traffic is complicated, by providing a actual maritime traffic data. It can be usefully used to develop and advance technologies related to maritime autonomous surface ships and intelligent maritime traffic information services in coastal waters. In addition, it can be used as a 3D-based monitoring equipment for areas where physical monitoring is difficult but real-time maritime traffic monitoring is necessary, and can provide functions to safely manage maritime traffic situations such as aerial views of ports/control areas, bridge views/blind sector views of ships in operation.

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