• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.6
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• pp.650-655
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• 2019

The age and growth of Muraenesox cinereus collected in the South Sea of Korea by Danish seine and coastal Long-line fisheries were determined from right sagittal otoliths between May 2018 and April 2019. Otoliths of 353 fish were observed under reflected light, and the edges of the opaque zone were considered to be the otolith ring. Monthly changes in the marginal index indicated that rings (opaque zones) were formed once a year from June to July. The estimated von Bertalanffy growth equation with growth parameters estimated from non-linear regression were L_t=138.37 (1-e^{-0.18(t+0.79)}) for females and L_t=99.00 (1-e^{-0.13(t+3.99)}) for males. The oldest female M. cinereus was 12 years old, and the oldest male was 8 years old.

• Proceedings of KOSOMES biannual meeting
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• 2005.05a
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• pp.209-213
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• 2005

The current AIS network and. system are run on a full scale with 22 ground stations and. 11 operational systems, completing a nation-wide, integrated network However, currently it needs to manage sea traffic by linking AIS to VIS which 1vs a limited service area due to restricted radar detection zones in harbors or coastal areas. Accordingly this study analyzes the current status of the AIS system and. proposes technological and. operational improvement plan of the current AIS system through investigating the actual conditions of the AIS system and. its operations.

• Aerospace Engineering and Technology
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• v.12 no.1
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• pp.144-151
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• 2013

The KOrea Multi-Purpose SATellite-2 (KOMPSAT-2) is to provide 1.0 m Ground Sample Distance (GSD) panchromatic image and 4.0 m GSD multi-spectral image data for various applications. The KOMPSAT-2 system performs mission applications in the field of earth observations, covering land, sea, coastal zones, and Geographic Information Systems (GIS). The purpose of this document is to compute ground coordinate using satellite position, velocity and attitude data in KOMPSAT-2 and document for work-flow of location accuracy correction in KOMPSAT-2.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• no.2
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• pp.130-139
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• 2004

Shiwha Lake is an excellent example of a body of water restored from a state of heavy pollution to a cleaner and more ecological state. This paper will explore techniques and methods available to landscape planning for the creation of new migratory birds habitats in Shiwha Lake. Because Shiwha lake is located adjacent to a new industrial site on reclaimed land, any planning effort aimed at restoring bird habitats must carefully consider the existing context. This plan had 3 goals; (1) to restore the coastal environment, (2) to create a habitat for migratory birds, and (3) to administer environmental education programs. To achieve these goals, several objectives were determined and planning criteria were proposed for topology, water environment(fresh, brackish and salt water swamps), zoning(for experts and general visitors), circulations, planting and mounding. The flora and fauna of the site was surveyed, and 5 alternatives were suggested and compared in several aspects. Planting species were carefully selected considering target birds and habitat requirements. In order to increase bio-diversity of the site, the plan proposed multi-staired mounds and extensive drainage systems. Bird watching facilities with natural materials, and the remote observing system using CCTV and the internet were some of the ecological techniques recommended by the plan. The bird watching trails are divided into two different zones for experts and general visitors.

• Journal of Fisheries and Marine Sciences Education
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• v.23 no.4
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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.

• Wind and Structures
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• v.28 no.6
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• pp.389-404
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• 2019

In coastal regions, it is common to witness significant damages on low-rise buildings caused by hurricanes and other extreme wind events. These damages start at high pressure zones or weak building components, and then cascade to other building parts. The state-of-the-art in experimental and numerical aerodynamic load evaluation is to assume buildings with intact envelopes where wind acts only on the external walls and correct for internal pressure through separate aerodynamic studies. This approach fails to explain the effect of openings on (i) the external pressure, (ii) internal partition walls; and (iii) the load sharing between internal and external walls. During extreme events, non-structural components (e.g., windows, doors or rooftiles) could fail allowing the wind flow to enter the building, which can subject the internal walls to lateral loads that potentially can exceed their load capacities. Internal walls are typically designed for lower capacities compared to external walls. In the present work, an anticipated damage development scenario is modelled for a four-story building with a stepped gable roof. LES is used to examine the change in the internal and external wind flows for different level of assumed damages (starting from an intact building up to a case with failure in most windows and doors are observed). This study demonstrates that damages in non-structural components can increase the wind risk on the structural elements due to changes in the loading patterns. It also highlights the load sharing mechanisms in low rise buildings.

• Journal of Species Research
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• v.10 no.3
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• pp.276-286
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• 2021

We performed a taxonomic study on Korean Pacificincolidae (Bryozoa: Cheilostomata) with the materials collected from 39 localities(ports, intertidal and subtidal zones) in the coastal seas of South Korea from 1981 to 2020. Korean Mucronella perforata reported by Rho and Seo (1985) turned out to be not Pacificincola perforata, but Primavelans glabricollaris n. sp. based on morphological data. Pacificincola perforata, which was transferred from Mucronella perforata (Okada and Mawatari, 1937), is also added to the Korean fauna. This study is the first to use mitochondrial 16S rRNA gene sequences to study the family Paficincolidae. The NJ analysis also reconfirmed the validity of the genus Primavelans, established on the basis of the early astogeny by De Blauwe in 2006, with the mitochondrial 16S rRNA sequences. The inter-genetic distance among two species belong to the Pacificincolidae was in the range of 13.39±1.83 mm. Primavelans glabricollaris n. sp. is thus distinguished from Pacificincola perforata with both morphological and molecular data. A new species, Primavelans glabricollaris, and a new record, Pacificincola perforata from Korea are herein described in detail and illustrated by scanning electron microscopy.

• Journal of Species Research
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• v.11 no.3
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• pp.180-187
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• 2022

We found three fouling bryozoans from the materials collected from seven localities (ports, yacht marina, intertidal and subtidal zones) in the coastal seas of South Korea from 2003 to 2021. These three species, Thalamoporella californica (Levinsen, 1909), Scruparia ambigua (d'Orbigny, 1841), and Tricellaria inopinata d'Hondt and Occhipinti Ambrogi, 1985, and one genus Scruparia Oken, 1815 are newly added to the Korean bryozoan fauna. Of the three species, Scruparia ambigua and Tricellaria inopinata are cosmopolitan or widespread, and Thalamoporella californica is from the East Pacific Ocean in tropical/temperate water. It seems that some of the previously reported T. occidentalis in Korea have a high probability of being T. inopinata. In this study, some Tricellaria occidentalis reported by Seo (2005) are synonymized into T. inopinata. A total of 77 species of fouling bryozoans has been reported in Korea, with three new bryozoans resulting from this study. Descriptions and illustrations of the three fouling bryozoans using scanning electron microscopy are provided in this study.

• Geomechanics and Engineering
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• v.32 no.2
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• pp.209-232
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• 2023

A comprehensive study was conducted to design economical foundations for a number of buildings on soft cohesive soil in the southern coastal regions of Iran. Both static and seismic loads were considered in the design process. Cyclic experiments indicated that the cohesive soil of the area has potential for softening. Consequently, the major challenge in the design stages was relatively high dimensions of settlement, under both static and seismic loadings. Routine soil-improvement methods were too costly for the vast area of the project. After detailed numerical modeling of different scenarios, we concluded that, in following a performance-based design approach and applying a special time schedule of construction, most of the settlement would dissipate during the construction of the buildings. Making the foundation as rigid as possible was another way to prevent any probable differential settlement. Stiff subgrade of stone and lime mortar under the grid foundation and a reinforced concrete slab on the foundation were considered as appropriate to this effect. In favor of an economical design, in case the design earthquake strikes the site, the estimations indicate no collapse of the buildings even if considerable uniform settlements may occur. This is a considerable alternative design to costly soil-improvement methods.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.4
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• pp.204-212
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• 2005

Recognition has emerged that nutrient inputs from the submarine discharge of fresh, brackish, and marine groundwaters into the coastal ocean are comparable to the inputs via river discharge. The coastal areas of the Korea peninsula and adjacent seas exhibit particular importance in the role of submarine groundwater discharge (SGD), in terms of the magnitude of SGD and associated continental material fluxes. For example, in the southern sea of Korea, SGD transports excess nutrients into the coastal regions and thus appears to influence ecosystem changes such as the outbreak of red tides. Around volcanic island, Jeju, which is composed of high permeability rocks, the amount of SGD is higher by orders of magnitude relative to the eastern coast of North America where extensive SGD studies have been conducted. In particular, nutrient discharge through SGD exerts a significant control on coastal ecosystem changes and results in benthic eutrophication in semi-enclosed Bang-du bay, Jeju. In the entire area of the Yellow Sea, tile submarine discharge of brackish groundwater and associated nutrients are found to rival the river discharges into the Yellow Sea, including those through Yangtze River, Han River, etc. In the eastern coast of the Korea peninsula, SGD is significantly higher during summer than winter due to high hydraulic gradients and due to wide distribution of high permeability sandy zones, faults, and fractures. On the other hand, in the estuarine water, downstream construction of the dam in the Nakdong River, SGD was highest when the river discharge was lowest (but water level of the dam was highest). This suggests that even though there is no visible freshwater discharge into this estuary, the discharge of chemical species is significant through SGD. On the basis of the results obtained from the coastal areas of the Korea peninsula, SGD is considered to be an important pathway of continental contaminants influencing tidal-flat ecosystems, red tides, and coral ecology. Thus, future costal management should pay great attention to the impact of SGD on coastal pollution and eutrophication.