• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.1
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• pp.67-79
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• 1995

Temporal variation of demersal fish in Asan Bay was determined by analyzing seasonal samples collected by an otter tyawl from November 1990 to August 1993. Of 49 species identified, Cynogiossus joyneri, Thrissa koreans and Johnius belengerii predominated in abundance, consisting of $84.7\%$ in fish numbers and $70.5\%$ in biomass. The number of species did not show any significant seasonal variation. Fish numbers and biomass were comparatively high 3n spring, summer and tall, and low in winter. Community structure, analyzed by principal component analysis using rank correlation, showed a clear seasonal trend, which seems to be related to the seasonal effects such as temperature. The number of species and their abundance in the study area were lower than those in other embayments of Korean peninsula. It seems that unstability of the sediments by tidal mixing caused this phenomenon. The total number of species decreased annually. The species of which the frequency of occurrence tends to diminish as time were mainly composed of the species which rarely occurred with low abundance.

• Economic and Environmental Geology
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• v.45 no.1
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• pp.41-48
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• 2012

A theoretical $CO_2$ storage capacity is estimated on the southwestern continental shelf margin of Ulleung Basin, offshore Korea using 2D/3D multi-channel seismic and wellbore data acquired in the area over the two decades since the late 1980s. For the first time in Korea, the present study applies an efficiency factor to the capacity calculation, together with the other required parameters. For possible $CO_2$ storage volume estimation of the study area, we interpreted the seismic data in the Gorae area from 800 m to 3,000 m below the seafloor integrated with the well data, and identified five different seismic units; the limited depth interval is considered because of fluid state of $CO_2$ and tightness of the formation. The total volumes of each seismic unit were converted with a time-depth relation inferred from the checkshot surveys before the other required parameters including porosity and density were applied to compute the potential storage capacity. The accumulated possible storage volume from the five depositional units in the study area is estimated to be approximately 5,100 Mton ($P_{50}$). The approaches made in this study will be applied to the rest area of the basin and other continental shelves (i.e., Yellow Sea and northern part of East China Sea) in the next phase.

• Journal of the Korean Society of Marine Environment & Safety
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• v.9 no.2
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• pp.59-64
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• 2003

The long­term trend and inter­relationship with depth of temperature and salinity in coastal waters of Korea are studied using coastal oceanographic observation and serial oceanographic data measured by National Fisheries Research and Development Institute. Temperature of coastal waters of Korea except south­western sea of Korea where cold water appears to increase in summer. In case of temperature offshore, surface temperature of East Sea increases, the reverse, for 50m and 100m decreases. Temperature in South Sea of Korea increases in whole depth and for the Yellow Sea, surface temperature increases, but for 50m decreases. In case of salinity offshore, surface salinity of East Sea decreases, but for 50m increases. Surface salinity in South Sea of Korea decreases, the reverse, form 50m and 100m increases. salinity in the Yellow Sea decrease in whole depth According to the result of inter­relationship analysis, for temperature relationship coefficients of 50m and 100m in the East Sea and South Sea of Korea is higher, however, for the Yellow sea the inter­relationship between 50m and 100m is lower. In case of salinity, the inter­relationship between surface and 50m, and for the South Sea of Korea, between 50m and 100m, and for the Yellow Sea, between surface and 50m is higher.

• Journal of the Mineralogical Society of Korea
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• v.27 no.3
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• pp.107-114
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• 2014

In this study, we tried to determine the origin of fine-grained sediments in Southeastern Yellow Sea Mud patch (SEYSM) using principal component analysis coupled with semi-quantitative X-ray diffraction analysis for 4 major clay minerals. We used 51 marine surface sediments from SEYSM and 33 surface sediments of rivers flowing into the Yellow Sea. We made bioplot diagram using R program with principal component 1 and component 2 because the two components might contain about 98% of all data. The content of each clay mineral in the south and north regions of SEYSM are almost similar. In the biplot, SEYSM sediments distribute close to Korean rivers sediments than Huanghe and Changjiang sediments. Based on these results, we suggest that SEYSM is originated from the Korean rivers sediments. The higher accumulation rate in the SEYSM compared to the sediment discharge from neighboring Korean rivers can be explained by erosion and reworking of surface sediments in this area. The principal component analysis can be used for the provenance research of marine sediments around the Korean Peninsula.

• Strategy21
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• s.41
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• pp.333-370
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• 2017

북한의 SLBM 위협이 대한민국 안보에 미치는 영향에 대해 그동안 많은 논의가 있어 왔지만, 북의 잠수함에서 발사하는 탄도미사일이 보유한 진정한 위협에 대한 인식은 아직도 부족한 듯하다. 그 이유는 대부분의 논의가 북 SLBM 기술의 성숙도와 완성시기 등 기술적 수준에 관심이 치우쳐져 있기 때문이다. 핵전략과 억제전략의 관점에서 본다면 북한의 SLBM 개발은 한미동맹의 제1격에 대한 완벽한 제2격 능력 보유에 그 핵심이 있다. 즉 향후 개발될 북한의 SLBM은 평양 김정은 정권의 생존을 보장할 직접적이고 핵심적인 전력이 될 것이다. 이는 궁극적으로 한미 군사동맹과 북한의 현 군사력 균형을 깨뜨리고 앞으로 북의 군사도발 가능성을 더욱 높이는 결과를 가지고 올 것이다. 북의 핵전략은 현재 확증보복(assured retaliation) 단계로 발전하고 있으며, 결국에는 전쟁에 사용될 전술적 핵무기 능력(war-fighting capability)을 갖게 될 것이다. 이에 대한민국 해군은 우리의 강점을 활용하여 적의 약점을 공략할 수 있는 상쇄전략(offset strategy)을 개발하여야 한다. 북한의 현 제한된 잠수함 기술력과 대잠작전 능력을 고려할 때 한국해군은 수중영역에서의 공세적 대잠전(offensive ASW) 개념을 보다 발전시켜야만 할 것이다. 이는 미 해군이 냉전기간 중 소련해군 핵추진전략잠수함(SSBN) 대응을 위해 발전시킨 전략대잠전(strategic ASW) 개념에서 교훈을 얻을 수 있다. 미 해군은 소련 해군의 SSBN 을 억제하기 위해 공세적인 전략대잠전을 수행했고 그 결과 소련해군은 자국의 연안에서 벗어나지 못하는 요새전략(bastion strategy)를 추구할 수밖에 없었다. 당시 미 해군의 전략대잠전은 공격잠수함(SSN), 대잠초계기, 수중 탐지체계(SOSUS), 공격기뢰 등의 전력으로 구성되었다. 따라서 북한 SLBM 에 대한 한국해군의 전략개념은 북의 핵전략(제 2 격능력)을 억제하는 방향으로 정립되어야 하며, 이를 위한 해군력 건설은 대잠전 능력 강화에 초점을 맞추어야 한다. 우리 해군은 장기적으로 핵추진잠수함을 비롯하여 성능이 향상된 대잠초계기, 한반도 해역을 중심으로 한 미 해군의 SOSUS 와 유사한 수중탐지장비 그리고 장시간 수중작전이 가능한 무인잠수정(UUV)을 도입해야만 한다. 단기적으로는 현재 추진되고 있는KAMD 체계에 SM-3 를 보유한 이지스함을 포함시켜, 북 SLBM 에 대한 요격능력을 강화해야 할 것이다. 한미동맹은 북 핵전략의 핵심전력인 SLBM 개발에 대한 위협인식을 공유해야만 하다. 작전적 수준에서는 양국 해군 간 대잠전 및 대유도탄전 작전운용성 증대에 우선순위를 두고, 기존의 한미 간 연합작전능력 강화뿐 아니라 위기시를 대비하여 미일 간 구축되어 있는 대잠전 및 대유도탄전 능력도 활용할 필요가 있을 것이다.

• Spatial Information Research
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• v.16 no.3
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• pp.331-342
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• 2008

The countries are trying to expand the sea limit such as the territorial sea, fishing zone or the exclusive economic zone as far as the Law of the Sea permit to do for the benefit of their national interest. Especially, they are eager to claim the base point where it locates far from the coastline even if it is uninhabited island or reef under the sea. The baseline has been claimed to maximize the territorial sea. Another way to expand the sea limit is to lower the vertical datum to change the land limit. China claimed Dongdo which is located about 79 miles far from the coast as the base point. Japan also claimed many uninhabited island or the reef which is located very far from the coast such as Okino Dorishima. As Korea is the party who negotiate the maritime limit with Japan and China, we should be keen and sensitive on the issues claimed by neighboring countries in terms of base point and the baseline. This paper is to review the characteristics of the base points or baselines of neighboring countries and to suggest the views how to maintain and to relocate our base points. As western coast of Korean peninsula is one of the largest tide fluctuation zone in the world, with long tidal record to prove the vertical datum adjustment, Korea can find the way to lower the vertical datum especially in Yellow Sea. So, major and critical tidal station has to be set up along the western coast to verify tide fluctuation record which can be met with international standard.

• 한국해양학회지
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• v.27 no.2
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• pp.123-136
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• 1992

As a result of faunal analysis on 50 bottom samples bearing a total of 183 species of the Recent benthonic foraminifers from the West and South Sea of korea, five bioassociations (groups of species) and five biotopes (groups of samples) were discriminated. From the areal distribution of biotopes in combination with bioassociations and the available ecological data of foraminiferal species, five biofacies are recognized: (1) Southern Inner Shelf Biofacies; (2) Southern Coast Biofacies; (3) Northern Middle Shelf Biofacies; (4) Central Middle Shelf Biofacies; and (5) Southern Outer Shelf and Upper Slope Biofacies. The biofacies are defined by a group of sampling stations containing a diagnostic species association and can be related to the major current pasterns and water masses in the West and South Sea of Korea: Southern Inner Shelf Biofacies is related to the Coastal Waters and drainage from China; Southern Coast Biofacies is related to the Coastal Waters and drainage from Korea; Northern Middle Shelf Biofacies is related to the Coastal Waters and Yellow Sea Cold Water, Central Middle Shelf Biofacies is related to the Yellow Sea Warm Current; and Southern Outer Shelf and Upper Slope Biofacies is related to the Tsushima Warm Current.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.464-473
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• 2016

The air temperatures of the coast and inland are rising due to an increase in carbon dioxide emissions and abnormal climate phenomena caused by global warming, El Nino, La Nina and so on. The sea levels of the Earth are rising by approximately 2.0 mm per year (global average value) due to the thermal expansion of sea water, melting of glaciers and other causes by global warming. On the other hand, when it comes to designing a hydraulic structure or coastal hydraulic structure, the standard of the design water level is decided by analyzing four largeness tide values and a harmonic constant with the observed tidal water level or simulating numerical model. Therefore, the design tidal water level needs to consider an increasing speed of the seawater level, which corresponds to the design frequency. In the present study, the observed tidal water levels targeting 46 tidal stations operated by the Korea Hydrographic and Oceanographic Administration (KHOA) from the beginning of observations to 2015 per hour were collected. The variation of the monthly and yearly and increasing ratio were performed and divided into 7 seas, such as east and west part of the Southern Sea, south part and middle of the East Sea, south part and middle of the Western Sea, and Jeju Sea. The current study could be used to determine the cause of local seawater rises and reflect the design tidal water level as basic data.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.171-178
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• 2018

The ocean is a harsh environment and Korea Coast Guard officers often face the threat of death or going missing in the line of duty. In order to promptly identify unknown bodies during mishaps, Korea Coast Guard Research Center has established an identification system using the DNA of its officers. This collected DNA can also be entombed in National Cemeteries when the remains are not recovered. The storage, disposal and quality control of the materials are overseen by the Governing Committee according to the Enforcement Rules for the Human Biological Materials Storage Project for the Identification of Officers Killed or Gone Missing in Action. Approximately 700 bodies are found per year along the Korean coast. An alternative method should be put in place for when identification through fingerprints and teeth are not applicable due to severe decomposition or partial recovery. We believe it would greatly contribute to helping identify the unknown bodies if the storage project could expand its data to include marine industry workers, relevant researchers and those involved in marine leisure activities.

• Spatial Information Research
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• v.19 no.6
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• pp.19-28
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• 2011

Recently, the interests of marine mineral resources has been increasing from the depletion of land resources around the world and many countries are involving in marine exploration work. South Korea is also currently performing exploration work to estimate the marine mineral resources around the Korean Peninsula. However, massive amounts of marine exploration data accumulated from the long-term exploration work have not been systematically managed. The data have been managed by the file based system instead of commercial database. The aim of this study is to construct GIS-based Marine Mineral Resource Information System using a spatial database for the core sediments of the marine exploration data. For constructing such DB system, GIS-based data items were classified, and a database was designed using relational database model. The database was constructed using commercial DBMS(Database Management System), Oracle. Also, necessary functions of the system were defined for the effective use of database based on users' requirement analysis. The GIS-based Marine Mineral Resource Information System has enabled to support the systematic management of the marine exploration data. Furthermore, it is expected that this spatial database will be useful in estimating the reserves of the mineral resources and provide valuable information for economic evaluation. In the future, the application of advanced techniques of spatial analysis and 3-dimensional display function will be required.