• Korean Journal of Remote Sensing
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• v.34 no.6_2
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• pp.1229-1238
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• 2018

We examined if a state of sea-ice in Bering Sea acts as a prelude of variation in that of Chukchi Sea by using satellites-based Arctic sea-ice concentration time series. Datasets consist of monthly values of sea-ice concentration during 36 years (1982-2017). Time series analysis armed with Transfer entropy is performed to describe how sea-ice data in Chukchi Sea is affected by that in Bering Sea, and to explain the relationship. The transfer entropy is a measure which identifies a nonlinear coupling between two random variables or signals and estimates causality using modification of time delay. We verified this measure checked a nonlinear coupling for simulated signals. With sea-ice concentration datasets, we found that sea-ice in Bering Sea is influenced by that in Chukchi Sea 3, 5, 6 months ago through the transfer entropy measure suitable for nonlinear system. Particularly, when a sea-ice concentration of Bering Sea has a local minimum, sea ice concentration around Chukchi Sea tends to decline 5 months later with about 70% chance. This finding is considered to be a process that inflow of Pacific water through Bering strait reduces sea-ice in Chukchi Sea after lowering the concentration of sea-ice in Bering Sea. This approach based on information theory will continue to investigate a timing and time scale of interesting patterns, and thus, a coupling inherent in sea-ice concentration of two remote areas will be verified by studying ocean-atmosphere patterns or events in the period.

• Korean Journal of Ichthyology
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• v.5 no.2
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• pp.177-183
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• 1993

Results comparing the scale and otolith ages for walleye pollock from the Donut Hole of the Bering Sea showed a significant discrepancy for fish older than 8 years old. For walleye pollock from the Shelikof Strait of the Gulf of Alaska, comparison between ages determined from the scale and otolith readings indicated that there were no differences for younger age groups, but for the ages 6 and older, discrepancies squeezed in somewhat amid the same age groups.

• Journal of the Mineralogical Society of Korea
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• v.24 no.1
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• pp.19-29
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• 2011

Clay mineral assemblages of core PC25A collected from the northern part of the Aleutian Basin in the Bering Sea were examined in order to investigate changes in sediment provenances and transport pathways. Ages of core PC25A were determined by both Last Appearance Datum of radiolaria (L. nipponica sakaii; $48.6{\pm}2\; ka$) and age control points obtained by the correlations of $a^{\ast},\; b^{\ast}$, and laminated sediment layers with the adjacent core PC23A, whose ages are well constrained. The corebottom age of core PC25A was calculated to be about 57,600 yr ago and core-top might be missing during coring execution. Average contents of smectite, illite, kaolinite, and chlorite during the last glacial period are 11% (5~24%), 47% (36~58%), 13% (9~19%), and 29% (21~40%), respectively. Clay mineral assemblages of the last glacial period are characterized by higher illite and lower smectite contents than those of core MC24 representing the modern values. Illite-rich clay sediments during the warm Early Holocene were transported from the northern part of Alaska continent (Province 1) through the ice-melt waters. During the deglacial period (B${\phi}$lling-All${\phi}$rod) of MIS 2, clay-sized particles seemed to be also transported by ice-melt waters mainly from Province 2 and Province 3 located farther south than Province 1. Higher smectite content during the Last Glacial Maximum is attributed to increased amounts of clay particles from the adjacent Alaska Peninsula (Province 4). From the early to the middle MIS 3, illite and smectite contents decreased, whereas chlorite content increased. With the low sea level standing during MIS 3 the supply of clay sediments from Province 2 and Province 3 was most likely intensified. Changes in clay mineral assemblages of core PC25A located in the northern part of the Aleutian Basin in the Bering Sea are closely related to the change of surface current system caused by sea level variation during the last glacial period.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.257-258
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• 2003

명태는 우리나라의 동해, 일본 근해, 오호츠크해, 베링해, 알라스카만과 북동태평양 연안을 따라 남부 오레곤까지의 북태평양에 널리 분포하는 냄수성 어종으로 우리나라 동해안에서 어획되는 명태는 주산란장이 함경남도의 마양도와 원산만으로 알려져 있다. 우리나라 동해안에서의 명태 어획량은 1971년에 11천들에서 매변 변동을 보이면서 증가하여 1981년에 166천톤으로 최고어획량을 기록한 후 급격히 감소하여 1988∼1993년에는 연간 2만톤 내외를 어획하였다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.342-343
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• 2000

대부분의 어류는 난과 자치어기를 지나 성어가 되면서 어장에 가입되므로 어란과 자치어의 분포밀도는 성어자원량을 파악하는데 중요하다. 일반적으로 물리적 환경 즉 수온과 해류는 어류 자치어의 분포, 성장 및 생존에 영향을 미치는 주된 요인으로 표층수온은 난의 발달과정을 조절하고 해류는 유영력이 미약한 자치어의 분포와 출현량에 영향을 미친다. (중략)

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.82-82
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• 2017

Chum salmon, Oncorhynchus keta, has received considerable attention in recent years for population genetic studies due to its broad geographic distribution and high commercial importance in North Pacific fisheries. The Bering Sea and North Pacific Ocean provide major feeding habitats for various salmon stocks originating from Japan, Russia and North America. Chum salmon are a dominant pelagic fish in the Bering Sea during summer and their numbers fall when they moved in coastal areas to spawn. Population genetic data for chum salmon that can serve as a baseline for stock identification studies are scarce. In this review, we describe recently developed molecular markers and discuss their use in the study of genetic population structure of chum salmon in the Pacific Rim. In addition, we review previous genetic studies focused on the assessment of stock compositions in mixed chum salmon aggregations in the Bering Sea and North Pacific Ocean.

• Korea Petroleum Association Journal
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• no.1 s.35
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• pp.106-109
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• 1984

지난 해 9월초의 런던 세계석유회의에서 체이스ㆍ맨하탄은행 부총재 베링씨는 「금후 10년간의 석유산업의 투자」라는 논문을 발표했다. 그 내용이 충실하고 문제점도 정확했다고 생각한 일본에너지 경제연구소장 생전풍랑씨는 지난 11월동경의 경단연회단에서 동회의에 관한 보고강연회를 가졌는바, 이하 그 요약이다. <역자주>

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.194-195
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• 2000

난바다곤쟁이는 북태평양 동부해역으로부터 베링해, 오우츠크해, 동해와 황해에 이르기까지 광범위하게 분포하는 종으로서 형태학적 분류관점에서 동일종으로 간주되고 있다. 최근에 밝혀진 황해 개체군의 생태학적 특성에 의하면 미국 서부해역과 황해에 서식하는 두 개체군은 지리적으로 멀리 떨어져 있음에도 불구하고 공히 비교적 낮은 수온 (< 1$0^{\circ}C$)의 수심에서 서식하며 강력한 일주수직상승운동 (diurnal vertical migration)을 수행하는 등 많은 특성을 공유하는 것으로 밝혀졌다 (Yoon et al., in press). 본 연구는 미국 서부연안과 한국 서해에 서식하는 난바다곤쟁이 개채군의 물리, 생태, 형태학적인 공통 특성이 유전학적인 측면에서도 관찰되는지를 조사하고자 한다. (중략)

• Journal of Navigation and Port Research
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• v.41 no.6
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• pp.451-466
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• 2017

Deep-sea fishing vessel No. 501 Oryong was fully flooded through its openings and sunk to the bottom of the sea due to the very rough sea weather on the way of evasion after a fishing operation in the Bearing Sea. As a result, many crew members died and/or were missing. In this study, a full-scale ship flooding sinking simulation was conducted, and the sinking process was analyzed for the precise and scientific investigation of the sinking accident using highly advanced Modeling & Simulation (M&S) system of Fluid-Structure Interaction (FSI) analysis technique. To objectively secure the weather and sea states during the sinking accident in the Bering Sea, time-based wind and wave simulation at the region of the sinking accident was carried out and analyzed, and the weather and sea states were realized by simulating the irregular strong wave and wind spectrums. Simulation scenarios were developed and full-scale ship and fluid (air & seawater) modeling was performed for the flooding sinking simulation, by investigating the hull form, structural arrangement & weight distribution, and exterior inflow openings and interior flooding paths through its drawings, and by estimating the main tank capacities and their loading status. It was confirmed that the flooding and sinking accident was slightly different from a general capsize and sinking accident according to the simple loss of stability.

• Ocean and Polar Research
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• v.30 no.3
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• pp.215-224
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• 2008

A piston core (MR06-04 PC23A) collected from the northern continental slope in the central Bering Sea has recorded the high-resolution millennial-scale variation of calcium carbonate ($CaCO3$) content during the last 65 kyr. An estimation of the age of the core sediments was carried out by using the lithologic correlation of the deglacial laminated layers with a neighboring core (HLY02023JPC), complementing the last appearance datum of both Lychnocanoma nipponica sakaii (54 kyr) and Amphimelissa setosa (85 kyr). The probable age of core MR06-04 PC23A was approximately younger than 65 kyr. Two distinct events of a significant increase of $CaCO3$ in the deglacial laminated sediments clearly correspond to MWP1A and MWP1B in the Bering Sea (Gorbarenko et al. 2005) and to T1ANP and T1BNP in the North Pacific (Gorbarenko 1996). These pronounced peaks of $CaCO3$ contents result from the elevated carbonate production in the surface water and the subsequent weakened dilution due to terrestrial input, along with an enhanced oxygen minimum zone. The $CaCO3$ contents are low (${\sim}2%$) during the last glacial period mainly because of a low carbonate production caused by an expanded sea-ice cover and an increased dilution by terrigenous particles due to their closer distance to the continent during the sea-level low stand. The occurrence of seven distinct $CaCO3$ peaks in core MR06-04 PC23A is remarkable during MIS 3 and MIS 4, and they most likely correlate to the short-term millennial Dansgaard-Oeschger events.