• Animal Systematics, Evolution and Diversity
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• v.22 no.1
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• pp.51-55
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• 2006

Two caridean shrimps, Eualus biunguis (Rathbun, 1902) and Argis toyamaensis (Yokoya, 1933), collected from the Korean continental slope of the East Sea at depths of 850-870 m are reported as new to the Korean caridean fauna with brief descriptions and illustrations. A hippolytid shrimp, E. biunguis, is distinguished from the congeners by the minute che1alike appearance of dactyli of the last three pereopods and the large pyriform eye. A crangonid shrimp, A. toyamaensis, differs from the Korean species of the genus in having the posterior acute spines of submedian carinae on the sixth abdominal somite.

• Journal of Navigation and Port Research
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• v.37 no.5
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• pp.499-509
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• 2013

Seafarers are one of the main engines driving economic growth in the maritime sector. The International Maritime (IMO) Organization estimated that there were approximately 1.5 million seafarers around the world engaged in international trade in 2012. Data have shown that human casualties in maritime accidents around Japan have shown an increasing trend over the last ten years. One cause is human error, which is inseparable from the human element that influences mariner's decisions and actions. The Personal Identification (PIN) Safe method is one way to systematically identify substandard and unsafe actions by considering the error taxonomies associated with various scenarios for a maritime system. The results are based on analysis of the role of the human element in commonly reported unsafe actions when interacting with equipment and other systems. Furthermore, patterns of influencing shaping factors were observed on the basis of data processing; the aim of this study was to promote safety culture and provide an opportunity to improve safety at sea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.4 no.3_4
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• pp.99-102
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• 1971

The present paper deals with secular analysis of zooplankton biomass in the eastern area of the Yellow Sea during the last seven years from 1963 to 1969. The annual variation of zooplankton biomass in the research area shows increase since October 1965, the lowest point. The increasing shape is a parabola expression, BM= 0.0146 $T^2+0.0448T+38.0436$ (BM, Biomass; T, Time, of which zero point is placed at December 1965).

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.560-564
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• 2009

This paper introduces measurement and evaluation of vibration of the ship propulsion machinery (ISO 20283-4). ISO 20283-2 for measurement of structural vibration on ships was finalized last year and ISO 20283-4 was drafted and reviewed by particulate ISO members now. As the importance and core field in ISO 20283-4, the torsional vibration of propulsion system for sea going vessels should be analysed in design stage and it should be confirmed by the its measurement during the sea trial. Criteria for evaluation of torsional loadings are defined by IACS (International Association of Classification Societies) UR M68. In this paper, the author introduced the important and controversial matters during the review of ISO 20283-4.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.2
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• pp.1-7
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• 1992

The computational methods of extreme sea level are developed in this study. Based on type III asymptotic distribution, non-linear multiple regression method, skewness method and maximum likelihood method are used to evaluate the parameters of the distribution. The difference between real data and evaluated distribution function is fitted to get more desirable accuracy by employing polynominals. The numerical examples are given in the last section in order to illustrate the application of the present scheme.

• Journal of Species Research
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• v.9 no.4
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• pp.480-488
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• 2020

The genus Eurycletodes Sars, 1909 is reported for the first time in Korea. A new species of the genus Eurycletodes was collected from Hansando Island, South Sea of Korea. So far, Eurycletodes comprises 27 species, with no previously recorded species reported in East Asia, including Korea. Eurycletodes (Oligocletodes) vadumus sp. nov. is morphologically most closely related to E. (O.) denticulatus Por, 1967, E. (O.) aculeatus Sars, 1920, and E. (O.) diva Menzel, 2011, but clearly distinguishable from the others based on the following morphological characteristics: absence of A2 exopodal seta, A1 last segment with two inner setae, P4 exp-3 proximal inner seta modified, the ratio of length and of caudal rami (1.6 times), and mandibular palp with three setae. Together with the new species, the number of valid species in this genus has risen to 28. A key to species of the genus Eurycletodes is provided.

• Journal of the Korea Institute of Military Science and Technology
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• v.6 no.2
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• pp.55-64
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• 2003

Underwater acoustic noise measurement is an essential element for vulnerability assessment of modern naval platforms. But during the last few decades environmental conditions have drastically changed due to the gradually increasing sea ambient noise level and decreasing submarine radiated noise level. A real-time underwater acoustic measurement system with vertical line array is designed for the quiet submarine radiated noise assessment in challenging environment. This system has a constant directivity index in measurement frequency range and accurate tracking capability for the transmission loss compensation and navigation aids inside the submarine. This system has been validated at sea and used several times for the submarine noise measurement.

• Proceedings of the Microbiological Society of Korea Conference
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• 2003.05a
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• pp.13-15
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• 2003

Studies on marine microbial diversity using direct analysis of rRNA sequences have revealed previously unrecognized microbes and novel phylogenetic lineages that represent major components of global microbial assemblages. This diversity in the marine biosphere offers opportunities for research and application in the field of biotechnology; global gas exchange, nutrient and element cycling, biomass md food production, marine bioproducts, and bioprocesses. Especially, deep-sea encompasses the extremes of virtually at] environmental parameters found on Earth and provides extreme microorganisms. In this study several extreme microorganisms were successfully isolated from the deep-sea sediment samples obtained by joining ocean cruises for last 2 years and some of them will be introduced.

• Proceedings of the KSRS Conference
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• v.1
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• pp.475-478
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• 2006

Total primary production resulting from the photosynthetic process can be defined as the amount of organic matter produced in a given period of time. It is proportional to the chlorophyll-a (chl-a) values in the surface layer of the ocean. The MODIS board on Aqua satellite measures visible and infrared radiation in 36 wavebands, providing simultaneous images of chl-a concentration and sea surface temperature (SST) in the upper layer of the sea. The seasonal distribution of chl-a concentration during one year from April 2005 to March 2006 was examined. Light has a role of starting the seasonal cycle. The Kuroshio Current in this area induces many oceanographical features affecting to the change of seasonal control. The chl-a concentration is also seasonal, which is low in summer and high in winter. In summer, the meandering of Kuroshio Current induces strong eddies and increases the chl-a concentration. In autumn, the delayed small autumn bloom occurred until last December due to the Kuroshio Current. When the Kuroshio axis moves far from the coast, the coastal water dominates and increases the concentration even in the winter. The spring bloom starts early at the beginning of March and decreases during the spring.

• Journal of the Korean earth science society
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• v.29 no.6
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• pp.454-465
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• 2008

Benthic foraminiferal assemblage and AMS radiocarbon dating of core sediments from the northern shelf of the East China Sea were analyzed in order to understand the paleoenvironment and sedimentary environmental changes around the Korean marginal seas since the last glacial maximum (LGM). The core sediments, containing continuous records of the last 16,000 years, reveal a series of well-defined vertical changes in number of species (S), P/T ratio and species diversity (H) as well as foraminiferal assemblage. Such down-core variations display a sharp change at a core depth of approximately 240 cm, which corresponds to ca. 10,000 year B.P. The sediments of the lower part of the core (240${\sim}$560 cm, Zone I), including the well-developed tide-influenced sedimentary structures, are characterized by high abundances of Ammonia beccarii and Elphidium clavatum (s.l.) and low values in number of species, P/T ratio and diversity. These tide-influenced signatures and foraminiferal assemblage characters suggest that the sediments of Zone I were deposited in a coastal environment (water depths of 20${\sim}$30 m) such as tidal estuary with an influence of the paleo-rivers (e.g., old-Huanghe and Yangtze rivers) during the early phase of the sea-level rise (ca. 16,000 to 10,000 years) since the LGM. In contrast, the upper core sediments (0${\sim}$240 cm, Zone II) are characterized by abundant Eilohedra nipponica and Bolivina robusta with a minor contribution of A. ketienziensis angulata and B. marginata. and high values in number of species, P/T ratio and diversity. Based on relative abundance of these assemblage, Zone II can be divided into two subzones (IIa and IIb). Zone IIa is interpreted to be deposited under the inner-to-middle shelf environment during the marine transgression in the early Holocene (after ca. 9,000 yr B.P.) when sea level rapidly increased. The sediments of zone IIb most likely deposited after 6,000 yr B.P. under the outer shelf environment (80${\sim}$100 m water depth), which is similar to modem depositional environments. The muddy sediments of zone IIb were probably transported from the old-Huanghe and Yangtze Rivers during the late Holocene. We suggest that the present-day oceanographic conditions over the Yellow and the East China Seas have been established after ca. 7,000${\sim}$6,000 yr B.P. when the Kuroshio Current began to influence this area.