• Title/Summary/Keyword: shore

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Community Structure and Vertical Distribution of Macrobenthos in the Mussel Bed on the Goijeong Rocky Shore in Jinhae (진해 괴정 암반 조간대 담치대의 대형저서동물 군집구조 및 수직분포)

  • PAIK Sang-Gyu;YUN Sung Gyu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.36 no.5
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    • pp.500-508
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    • 2003
  • The fauna associated with mussel (Mytilus galloprovincialis) beds and vertical distribution of macrobenthos were studied on the Goijeong rocky shore in Jinhae Bay, Korea. Sampling was conducted seasonally using a quadrate from January to October, 1998. In the first experiment, to reveal the community structure of macrobenthos in mussel bed, a total of 62 species $(10,690ind./m^2,\;3,802.1\;g/m^2)$ were identified, which included polychaetes $(32\;spp.,\;52.6\%),$ molluscs (16 spp.), crustaceans (10 spp.), and others. The density-dominant species were Pseudopolydora antennata, Nereis heterocirrata, Littorina brevicula and Balanus kondakovi. And the density of associated fauna was correlated with that of mussel (r=0.951, p=0.049). In the second experiment, to reveal the vertical distribution of macrobenthos on the rocky shore, ANOVA showed highly significant differences between the density of top 5 dominant species (Chthamalus challengeri, Littorina brevicula, Balanus kondakovi, Septifer virgatus and Granulilittorina exigua) and tidal levels (P=0.000). Vertical distribution of macrobnethos was characterized by Ghthamalus belt and Balanus-Septifer belt in the mussel bed.

Charging Korean Off-Shore Fisheries for Sustainable Fishing (지속적 어업을 위한 적정 자원이용료 부과에 관한 연구)

  • 박성쾌;김기수;김은채
    • The Journal of Fisheries Business Administration
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    • v.33 no.2
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    • pp.49-74
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    • 2002
  • This study examines, from an economic perspective, the reasons for introducing a resource taxe system into the Korean off-shore fisheries and the type of charges that can be introduced. Following a review of the charging systems in other advanced fisheries, we consider the types of charging scheme and some implications for the Korean off-shore fishing industry. Charges could be used for recovering part of fisheries management cost from the industry(i.e. administration, enforcement, research, etc). This can be justified on the grounds that the fishing industry is the main beneficiary of management and that it should therefore bear at least part of the cost involved. It is arguable that publicly-funded management is in effect a subsidy to the industry. Using charges to raise revenue in excess of the cost of management would represent the extraction of a public rent from the fishery resource, but the short-run financial consqquences for the industry would be significant. Results from a qualtitative analysis suggest that while any new charge will have a significant financial impact on the industry in the short run, a landings tax would have a lesser impact on fleet structure in the long run. The study also considers the possibility of a capital gains tax on license sales in order to recover some rent from the industry. Despite any short run-financial consequences, making the fishing industry pay for at least some of the cost of management could benefit the industry as a whole if there were more cooperation between industry and managers as a result. It is acknowledged, however, that there could be disputes over the relative management costs of different sectors of the industry. Even though this study makes few specific recommendations about charging the Korean off-shore fishing industry, it does advise that the issue be reviewed on the basis of the entire Korea fisheries. Finally, the study notes that insufficient data are available on the economic performance of the Korean off-shore fishing vessels and it recommands that a comprehensive system for the collection of costs and earnings data be put in place. It also suggests that MOMAF pay much attention to the permit right market and its transactions.

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A Study on the Development of Corrosion Prediction System of Reinforcing Bars in Sea-shore Structure (해양 구조물의 철근부식 예측기법 개발에 관한 연구)

  • 박승범;김도겸
    • Journal of the Korea Concrete Institute
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    • v.11 no.6
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    • pp.89-100
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    • 1999
  • Service life of concrete structures that are exposed to the environmental attack is largely influenced by the corrosion of reinforcing bare due to the chloride contamination. Chloride ions penetrate continuously into concrete from the environment, and chloride diffusion velocity is governed by a mechanical steady stage. In this study, a method is developed to predict corrosion initiation of reinforcing bars in the sea-shore structures, based on governing equations that take into account the diffusing of chloride ions and a mechanical steady state. As a result of this study, Corrosion Prediction System (CPS) is developed, and it can be used to determine an optimal time for repair and rehabilitation actions need to be taken. Futhermore, CPS assists the concrete mixing structures by predicting of chloride concentrations in concrete mixture, exposed to salt concentrations and service environment.

A study on the environment of waste shell and its recycling method (패각의 부존환경 및 재활용에 관한 연구)

  • 이인곤
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.10 no.2
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    • pp.159-165
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    • 2000
  • This study was investigated the environment of waste shells such as oyster, cockle and paphia on southern shore in korea and established the recycling method to prevent the environmental pollution, etc. The waste shells were reclaimed at public shore illegally or leaved on the surroundings of shore. The origin mechanism, XRD and TG-DTA analyses were performed to effective recycling of waste shells, and the optimal recycling method was preparation of the calcium carbonate. In this work, calcium carbonate and lime fertilizer of granular shape were prepared using the waste shell.

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Contribution of Ecological Surveys to Coastal Conservation: A Case in Soft Shore Study

  • Tai, K. K;Cheung, S.-G;Shin, P.-K.-S.
    • The Korean Journal of Ecology
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    • v.27 no.3
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    • pp.127-131
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    • 2004
  • Soft shores are particularly vulnerable to human exploitation; however, they exhibit a variety of habitats which provide refuge for a diversity of flora and fauna. This study describes a survey of 13 soft shores in Hong Kong with information on species diversity, sediment characteristics, shore extent, pollution threat, degree of naturalness, linkage with other ecological habitats, and degree of social/economic importance. Data collected were subjected to multivariate statistical analyses, so as to identify shores that have significant ecological status and conservation value for management purposes.

Shore power to ships and offshore plants with flywheel energy storage system

  • Jeong, Hyun-Woo;Ha, Yun-Su;Kim, Yoon-Sik;Kim, Chul-Ho;Yoon, Kyoung-Kuk;Seo, Dong-Hoan
    • Journal of Advanced Marine Engineering and Technology
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    • v.37 no.7
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    • pp.771-777
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    • 2013
  • This paper describes a study of major shipyard's electrical network and simulation of applying flywheel energy storage system on the electrical network at shipyard for shore-power to ships and offshore plants in order to save fuel consumption on engines, mitigate voltage sags, and prevent blackout due to pulsed load and fault, resulting in reduction of air emission into atmosphere. The proposed energy recycling method with FESS (Flywheel Energy Storage System) can be applied for electrical power system design of heavy cranes at shipyards.

Study on Stress Variation in Slab and Support of Shearwall-Type RC Apartment during Construction (전단벽식 아파트에서 시공중 슬래브 및 동바리의 응력변화에 대한 연구)

  • Kim Young-Chan
    • Journal of the Korean Society of Safety
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    • v.19 no.4 s.68
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    • pp.161-165
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    • 2004
  • Safety and efficiency in the construction of RC structures mainly depends on optimal operation of shore-slat systems. The disasters in RC construction are mainly due to excessive load applied to falsework and premature removal of supports. Development of sufficient compressive strength of early-age connote is essential for the safety of structures during construction. Most of studies on shore-slab interaction have focused on flat slab structures. In this study, load distributions in floor slabs and supports during the construction of shear wall-type RC apartment building structures is investigated using finite element analysis.

Biodiversity and Community Structure of Marine Benthic Organisms in the Rocky Shore of Dongbaekseom, Busan

  • Yoo, Jong-Su
    • ALGAE
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    • v.18 no.3
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    • pp.225-232
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    • 2003
  • Species composition, community structure and biodiversity of marine benthic community were studied in the rocky shore of Dongbaekseom, Busan. A total of 82 species of marine algae including 4 Cyanophyta, 11 Chlorophyta, 20 Phaeophyta and 47 Rhodophyta are listed. The dominant algal species were Ulva pertusa, Chondria crassicaulis, Corallina spp. and Melobesioidean algae. Sargassum thunbergii, Chondracanthus intermedia, Gelidium divaricatum and Ralfsia verrucosa were subdominant in cases of different seasons and vertical layers. Chthamalus challengeri, Littorina brevicula and Mytilus edulis were dominant zoobenthic species upper-middle layer of the intertidal zone. The community structure of this area seemed to be controlled by spatial competition with benthic marine algae. The species diversity indices estimated from different sources were quite different. Indices from coverage were 1.87, 3.98 from frequency, 2.26 from the average of total frequency and coverage and 2.15 from importance value. The similarity indices on the present study showed decreasing trends comparing to the previous benthic algal composition researches.

Community Dynamics of Benthic Marine Algae in the Intertidal and Subtidal Rocky Shore of Samyang, Jejudo Island

  • Yoo,Jong-Su
    • ALGAE
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    • v.18 no.4
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    • pp.301-309
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    • 2003
  • Community structure and vertical distribution of benthic marine algae were investigated in the intertidal and subtidal rocky shore of Samyang, Jejudo Island. The total number of 62 algal species composed of 6 Cyanophyta, 6 Chlorophyta, 19 Phaeophyta, and 31 Rhodophyta were observed. The dominant species were melobesioidean algae, Sargassum thunbergii, Hizikia fusiformis, and Ulva pertusa in the intertidal zone and melobesioidean algae, Ulva pertusa, Corallina spp., and Undaria pinnatifida in the subtidal zone. The vertical algal distribution was represented by the melobesioidean algae in the whole rocky shore, Caulacanthus ustulatus in the upper intertidal zone, Sargassum thunbergii and Hizikia fusiformis in the middle and lower zone, Ulva pertusa in the lower zone and Ulva pertusa, Corallina spp., and Undaria prinnatifida in the subtidal zone. The composition of dominant species and pattern of the vertical distribution of algae in the present study were significantly different from the previous reports. Especially, distribution of crustose coralline algae was significantly extended.

A Numerical Simulation of the Shoreline Change and Sediment Transport with Shore Structures at Songdo Beach Youngil Bay, Korea (한국 영일만 송도 해수욕장의 해안선변화 및 표사이동율에 관한 수직 시뮬레이션)

  • 이중우
    • Journal of the Korean Institute of Navigation
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    • v.13 no.1
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    • pp.77-106
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    • 1989
  • Two numerical models of the shoreline change and sediment transport rates, explicit and implicit, are simulated with shore structures such as breakwaters, a jetty, groins and a seawall. The applied study area is songdo Beach, Youngil bay, Korea since it has all the shore structures mentinoed above. The two models investigate the beach line changes and sedimen transport rates for the beach before design of three groins with and without an offshore breakwater. In order to estimate the shoreline changes after three groins were built, the beach response inside the three groin compartiments and the offshore barrier are also investigated. The simulation based on the initial shoreline conditions surveyed by the Hydrographic office, Koreai 1979 and 1984. The breaking wave characteristics are introduced into the models by calculation from the empirical equations and modification from the numerical and hydraulic model test results developed for waves behind an offshore breakwater. The numerical simulation describes well the tendencies of the sand transport and shoreline changes affected by wave diffraction behind a detached breakwater and by interruption of sand transport at three groins.

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