• Title/Summary/Keyword: 어항

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Littoral Drift by the combined impact of Wind, Wave and Current ant the coastal Development Environment (해안개발환경하에서 바람 ${\cdot}$ 파랑 ${\cdot}$ 흐름의 중첩에 의한 연안표사)

  • Lee, Seung-Chul;Lee, Joong-Woo;Kim, Ki-Dam;Kang, Seok-Jin
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2007.12a
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    • pp.141-142
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    • 2007
  • In recent years, the rate of mean sea level rise is increasing rapidly from the phenomena of global warming, together with the increasing trend of the storm scale. The issue of sea level rise is multifaceted and produces a range of environmental problems. Especially, high tides and the tidal currents become higher, and wave base increases, so the energy received at the coastal boundary may increase. This brings that many coastal environments go into disequilibrium, such as damages to the structures, erosion, and deposition Similarly it was known that the problems of nearshore processes and damage of berth and counter facilities during storm period had appeared at the small fishery port. Here we try to analyze the impact of the rearrangement of counter facilities and berth layout adopted for tranquility of its'inner harbor. Because this harbor is being connected to channel and open sea, the rearrangement of the structures might affect to the current speed and direction and wave height, so do to the sea bottom undulation. Therefore, we made model test for the several layouts of the berth and breakwater in this area.

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Environmental Factors and Catch Fluctuation of Set Net Grounds in the Coastal Waters of Yeosu 3. The Quantity of Phytoplankton and Catch Fluctuation. (여수연안 정치강어장의 환경요인과 어항변동에 관한 연구 3 . 기초생산자의 출현과 어획량의 변동)

  • Kim, Dong-Soo;Rho, Hong-Kil
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.31 no.1
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    • pp.15-23
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    • 1995
  • In order to investigate the relation between the phytoplankton and the catch fluctuation of set net fishing grounds located in the coastal waters of Yeosu, phytoplankton observations on the fishing ground were carried out by the training ship of Yeosu, Fisheries University from April to November in 1990, and the data obtained were compared with the catch data from the joint market of yeosu fisheries cooperative society in 1990. The results obtained are summarized as follows: 1) The phytoplanktons were more appeared in summer than in spring or autumn and their quantity was much in the shore of Dolsan-do, and little in the offshore waters distributed in the shores of Sori-do and Sejon-do, Thus, the quantity of the planktons could be used for estimating the distribution of watermass. 2) The fishes caught by the set net were arranged in the order of catch amounts as follows: Spanish mackerel > Hair tail > Common mackerel > Sardine > Anchovy > Horse mackerel > Yellow tail. The catches of anchovy and Sardine were high in April to May and Hair tail. Horse mackerel and Common mackerel were caught from June to October. But Spanish mackerel were caught during the whole period of fishing. 3) The catches by set nets showed a correlation with the quantity of phytoplanktons. The planktons appeared most in the inner waters. influenced largely by the inflow of land waters in summer. and the catches were high in summer when the offshore water was distributed least. Therefore, the most important factor influencing the catches were regarded to be the productivity of food organism in inner water into which abundant nutrients were supplied by the inflow of land waters. That is, the fluctuation of catches by set nets seemed to be influenced mainly by the productivity of food organism.

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Statistical Analysis of Maritime Traffic Volume at Manila Bay, Philippines (필리핀 마닐라만의 해양 교통량 통계분석)

  • Dimailig, Orlando S.;Jeong, Jae-Yong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.18 no.4
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    • pp.323-330
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    • 2012
  • Manila Bay is home to the Port of Manila with three harbors: North Harbor, South Harbor and MICT(Manila International container Terminal). There is an adjacent fishing port to the north and another port across the Bay, the Limao Port. This study focuses on the volume of traffic movement in the Bay area taken from Manila VTMS raw data of the arrival and departure movements only. It is a two-year period of study of 2010 and 2011 traffic volume. It divides the data according to their numbers; to their sizes measured in gross tons; to the time of vessels' movements, whether daytime or night-time; and to each voyage trade: domestic or foreign. Quantitative values are calculated from the raw data based on the whole population of the two-year period. The results are illustrated by tables and graphs. Statistical measures are applied to determine the spread and frequencies of the data and test any significance from the hypotheses. These are shown in the tabulated form and interpreted to give a better picture of the frequency and volume of traffic. In the end, a summary is offered where it is hoped that this paper will propel further studies of improving the safety behavior in the premier port of the country.

Development of Dry Process Caisson Method for Maintenance of Submerged Harbor Structure (수중 항만구조물의 유지보수를 위한 건식 케이슨 공법 개발)

  • Lee Joong-Woo;Oh Dong-Hoon;Kwak Seung-Kyu;Kim Sung-Tae
    • Journal of Navigation and Port Research
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    • v.30 no.6 s.112
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    • pp.447-455
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    • 2006
  • Together with the trend of enhancement in domestic industrial development and economic progress due to import and export, the demand for construction of the roads, bridges, especially port facilities, and several coastal protection and ocean structures is increasing rapidly. MOMAF of Korean Government is driving construction cf 9 new ports and renovation cf the existing fishery ports. Among these structures most of bridge base, wharves, dolphins, quays, and jetties are being newly built cf steel or concrete pile. As the base, supporting bulkheads, and piles are underwater after construction, it is difficult to figure out the status of structures and not enough to get maintenance and strengthen the structures. Every year, moreover, these works suck the government budget due to higher incomplete maintenance expense for protection from corrosions cf structures and increased underwater construction period. For the purpose cf cutting down the expense cf government budget, it is necessary to extend the life cycle of the existing structures. Therefore, we developed a new method for maintenance of submerged structures near the waterline by allowing dry work environment with the floating caisson. The method shows easy to move around the working area and handle. It also showed not only a significant reduction of maintenance expenses and time for anti-corrosion work but also better protection This will be a milestone to reduce the maintenance and construction expenses for the shore and water structures.

The Efficient Anchorage Management of VTS through Analysis of Domain Watch (영역감시 분석을 통한 VTS의 효율적 정박지 관리 방안에 관한 연구)

  • Lee, Jin-Suk;Song, Chae-Uk
    • Journal of Navigation and Port Research
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    • v.42 no.3
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    • pp.201-206
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    • 2018
  • The purpose of this study is to estimate a proper Domain Watch between anchored vessels in order to propose a method for the efficient management of VTS(Vessel Traffic Service) of the N-anchorage in Busan harbor, which is the largest port in Korea. For this purpose, we proposed the calculation method of Domain Watch and investigated the ship length(L), the distance between anchored vessels ($D_{ij}$), the domain radius(R), and the domain radius vs L(R/L) during the peak time of the vessels in the latest usage of anchorage. As a result of technical analysis for the surveyed data, the minimum R/L for securing the safety distance between anchored vessels was selected based on 2.85 corresponding to the 70th percentile of the total data. This result was applied to the N-anchorage of Busan and compared with the 'Guidelines of Port and Harbor Design(2014)', and we have confirmed that it is reasonable to set the Domain radius with the minimum 2.85L or more in VTS. This study considers the safety management of anchorage for VTS. This study could contribute to the safety of vessels using anchorage and the safety management plan of VTS when it is applied to other ports in operation such as it was in Busan.

Strength Parameters and Shear Behaviors of North-Cheju Basalt Rubble Using Large-scale Triaxial Test (대형삼축압축시험을 이용한 북제주현무암 사석재의 강도정수 및 전단거동)

  • 정철민;김종수;채영수
    • Journal of the Korean Geotechnical Society
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    • v.18 no.2
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    • pp.147-160
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    • 2002
  • According to the Korean Design Code for port and harbor facilities, bearing capacity of rubble mound under eccentric and inclined load is calculated by the simplified Bishop method, and strength parameters are recommended to be c=0.2kg/$cm^2$ and \phi=35^P\circ}$ fur standard rubble if the compressive strength of parent rock is greater than 300kg/$cm^2$, according to research results by Junichi Mizukami(1991). But this facts have never been verified in Korea because there was no large-scale triaxial test apparatus until 2000 in Korea. For the first time in Korea, the large-scale triaxial test(sample diameter 30cm ; height 60cm) on the rubble originated from porous basalt rock in North-Cheju was accomplished. Then strength parameters for basalt rubble produced in North-Cheju are recommended to be c:0.3kg/$cm^2\; and \phi=36^{\circ}$ if the compressive strength of parent rock is greater than 400kg/$cm^2$. And the shear behavior characteristics of rubble, represented as particle breakage and dilatancy, are investigated.

A Systematic Approach to Decide Maximum Berthing Ship Size Coupled with Berth Design Criteria - A Case of Port of Ulsan - (부두 설계기준을 고려한 접안가능 최대선형의 결정에 관한 연구 - 울산항을 중심으로 -)

  • Jun, Sang-Yup;Kim, Young-Mo;Woo, Byung-Goo;Chung, Hyun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.14 no.1
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    • pp.45-54
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    • 2008
  • "Summer Deadweight Tonnage(SDWT)" is used as the criteria of the berthing capacity when establishing port entry limits under current guideline. The important factors affecting to the maximum ship size of possible berthing are mass, length and breath of the ship rather than deadweight. Therefore this guideline should be modified to ensure safety and efficient operation of berth. This study aimed to propose a rational guideline to adjust the berthing capacity. In order to decide proper berthing capacity, three berths of Port of Ulsan were selected and systematic evaluations for the safety of passage transit, berthing maneuvers, ship motions at berth and stabilities of structures were conducted. Small changes of ship size had little effect on those characteristics and little significant differences were found according to the increase of ship size at the same displacement. The evaluation results of the increasement of 50% of berthing capacity at 20,000 DWT, 25% at 40,000 DWT and 13% at 150,000 DWT were within the design criteria in which the berths were built. Therefore, if the channel width, diameter of turning circle, berth length and mooring arrangements are satisfied with the criteria, the current berth limitations should be adjusted by the displacement. as substitute for the deadweight.

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Diagnosis of Development Projects and Water Quality Changes in the Environmental Management Sea Areas and Improvement of Impact Assessment (환경관리해역의 이용개발현황과 수질변화경향 및 영향평가 개선방안)

  • Jun, Eun Ju;Yi, Yong Min;Lee, Dae In;Kim, Gui Young
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.6
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    • pp.726-734
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    • 2018
  • The total number of Sea Area Utilization Consultation in the environment management sea areas reviewed from 2015 to 2017 were 60. The number of development projects in the environment conservation sea areas decreased steadily, but special management sea areas increased. Development types in environment management sea areas showed that artificial structure installation was the highest ratio, followed by fishery port development and construction of habor and coastal maintenance and sea water intake and draining. By comparing the trend of water quality changes using marine environment information system (MEIS) data in the environment management areas from 2006 to 2017, COD showed no significant changes but the environment conservation sea areas increased slightly, and the concentration of TN and TP decreased. Gwangyang and Masan bays in the special management sea areas and Gamak bay in the environment conservation sea areas displayed oxygen deficient mass in the summer. As the use of development projects of the environment management sea areas are performed continuously, an analysis of the status of sufficient water quality changes is necessary for environmental impact assessment (Sea Area Utilization Consultation) in the marine environment and should be evaluated mainly for management of contamination by diagnosing thoroughly water quality effects and the pollution of sediment. Especially, the water quality goal for the purpose of designation in each of the environment management sea areas is set clearly, connection with pollution source control and the total pollution load management system (TPLMS) should be proposed and measured to reduce the amount of contaminated water.

Analysis of Numerical Experiment for Field Application of Cylindrical Slit Type Block Breakwater (실린더 슬릿형 소파블록 방파제의 실해역 적용을 위한 수치실험분석)

  • Park, Sang-Gil;Lee, Joong-Woo;Nam, Ki-Dae;Kim, Pill-Sung
    • Journal of Navigation and Port Research
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    • v.33 no.10
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    • pp.703-707
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    • 2009
  • In order to evaluate applicability of cylindrical slit type block breakwater to the field water, which was designed from the previous physical model study, it is analyzed the calmness of harbor area by the numerical model experiment. For a small fishery port in southern coast of Korea a SWAN model using the wave action balance equation was formulated. The reflection and transmission coefficients induced by the physical model test were introduced to the numerical model. The model response with cylindrical slit type breakwater was compared with the impermeable breakwater case and the possibility of water quality improvement through the water circulation by the new structure was investigated. For numerical simulation, parameters of deepwater design wave from the prediction report II for overall deepwater design wave by KORDI were used and wind parameters from the 50years return period observed for 37years(1970~2006) were adopted in the numerical model. The response of west breakwater in Mijo port applying the NE and NNE waves, which were dominant in this area, was analyzed. It was found that the transmission characteristic of designed cylindrical slit breakwater was well presented in the numerical model.

Hydraulic Characteristics Investigation due to the Change of GapWidth between Artificial Reefs (인공리프 개구폭 변화에 따른 흐름특성 고찰)

  • Kim, Kyu-Han;Shim, Kyu-Tae
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.28 no.6
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    • pp.408-415
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    • 2016
  • Small fishing ports and coastal structures installed in a relatively low sea water depth disturb the wave induced current and cause the collapse of equilibrium state of sediment transport. These structures creates diffracted waves and matter the concentration of waves to cause the beach erosion. In order to mitigate these eroding problems on the beach, many counter measurements were proposed such as detached breakwater, groin or headland; however, these methods interrupt the aesthetic view of sandy beach due to the exposed structures above the sea level and have difficulty of applying to those beaches with the good scenery. Furthermore, some of these methods create secondary environmental problems after the installations. To eliminate these problems, one of the countermeasures, artificial reefs have been selected and used worldwide to minimize the disturbance of the scenery and secondary effects on the environment. Meanwhile, it is important to set the design elements for installing the artificial reefs such as that of length, opening width, clearing distances from the shoreline and more. Nevertheless, there are no construction manuals or standards for designing the artificial reefs with these important design elements yet. In this study, different conditions of artificial reefs were used with various cases throughout hydraulic model test to precisely analyze the changes of waves and currents to propose the standards of design elements to install the artificial reefs.