• Title/Summary/Keyword: Marine Survey

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A Catalogue of the Mollusks of Jeju Island, South Korea

  • Noseworthy, Ronald G.;Lim, Na-Rae;Choi, Kwang-Sik
    • The Korean Journal of Malacology
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    • v.23 no.1
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    • pp.65-104
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    • 2007
  • This catalogue is the result of a four-year survey of the mollusks of Jeju Island, the southernmost island in the Republic of Korea. Forty-eight survey stations were visited, with a total of 82 specific localities being sampled. Literature records were also obtained. Local and world distribution of each species is included. This survey reports a total of 1,072 mollusk species and subspecies; 1,015 marine and 57 land and freshwater. There are 812 gastropods, of which 755 are either entirely marine or have marine affinities. The best represented of the marine families are the Pyramidellidae, Trochidae, and Ovulidae. There are 225 bivalves, none being freshwater species, with the Veneridae, Mytilidae, and Arcidae having the largest number of species. Among the smaller classes there are sixteen Cephalopoda, eleven Polyplacophora, and eight Scaphopoda. Compared to mainland Korea, Jeju Island has a rather small terrestrial mollusk fauna and a depauperate freshwater one, with mainly Palearctic connections. The Helixarionidae and Bradybaenidae are the largest terrestrial families. The marine faunal affinities with the neighboring Japonic and Indo-West Pacific provinces are also discussed, revealing that this island's mollusk fauna is a blend of warm-temperate and subtropical-tropical species.

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Marine Seismic Survey using a Multi-source System (다중음원 시스템을 이용한 해양 탄성파 탐사)

  • Kim, Hyun-Do;Kim, Jin-Hoo
    • 한국지구물리탐사학회:학술대회논문집
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    • 2006.06a
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    • pp.101-106
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    • 2006
  • Digital technology has been applied to marine seismic survey to develop data processing technology and multi-channel marine seismic survey. In result, high-resolution marine seismic survey ended in a success. Surveys are conducted for various purposes using various frequencies of acoustic sources. A low frequency source is used for deeper penetration and a high frequency source is used for higher resolution survey. In this study, a multi-source system was used for multi-channel marine seismic survey to acquire seismic sections of both low and high frequencies. Variations of depth of penetration and resolution would be used to achieve more accurate analysis of formations. In this study, the multi-source system consists of Bubble Pulser (400 Hz) for low frequency source and Sparker (1.5kHz) for high frequency source.

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Correlation of Marine Exploration-Survey Vessel Operation Factors and Grid-Type Operation Method through ES Model Analysis (환경스트레스 모델을 통한 해양탐사·조사선의 격자형 운항방식과 운항요인 상관관계에 관한 연구)

  • Park, Hyungoo;Park, Young-soo;Kim, Dae-won
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.6
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    • pp.634-643
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    • 2020
  • Because of the continuous increase in the demand for and importance of marine space, marine exploration and survey activities are being actively conducted in Korea actively. Because the marine survey vessels used for these activities have special operational patterns depending on the purpose and probe vessels, research on maritime traffic risk is required. In this study, an attempt was made to determine the correlation of each factor with the effect of marine exploration and survey vessel operation on maritime traffic. The status of ocean exploration and survey vessels in operation in Korea was identified, as well as the special operational conditions of some of the ocean physical probes. Generally, the number of exploration and survey vessels involved per hour, total vessel length(including exploration equipment), operation, interval distance of exploration as per plan, and marine traffic conditions(traffic volume and speed) can be classified as operating factors. To compare the results of the environmental stress, a maritime traffic flow simulation based on the "ES" Model was performed with each of the identified operating factors as independent variables. The results of the analysis confirmed that the environmental stress significantly changed in the order of traffic volume, ship length and speed. In addition, it was confirmed that the environmental stress is reduced when the operation course is set at an angle with the nearby maritime traffic flow. Accordingly, it can help reduce the operator's burden if the survey vessel operator understands nearby maritime traffic conditions and reflects them in the operation method when setting the operation plan.

A proposal of marine geophysical exploration techniques for offshore plant installation (해양플랜트 설치를 위한 해양물리탐사 기법 제안)

  • Ha, Ji-Ho;Ko, Hwi-Kyung;Cho, Hyen-Suk;Chung, Woo-Keen;Ahn, Dang;Shin, Sung-Ryul
    • Journal of Advanced Marine Engineering and Technology
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    • v.37 no.2
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    • pp.242-251
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    • 2013
  • Recently, while global concern over offshore resources exploration and development is being increased rapidly, offshore plant industry is highlighted as an industry of high added value. Along with this global trend, domestic concern over offshore plant development is being increased as well. In the overseas case, a marine geotechnical survey guideline for confirming characteristics of seabed sediments is available at the time of installation of offshore plant but such guideline is not available in our country. In this study, survey techniques fit for domestic marine environment was applied according to overseas guideline at southern coastal area, Korea. Among the marine geophysical survey techniques being proposed abroad, magnetic survey and seabed photograph were excluded. However, highly reliable data analysis was enabled for marine geophysical survey, which includes in-situ coring investigation and laboratory soil test. In addition, continuous ocean current survey was included to find scour potential due to the current around the offshore plant. Although coring depth is not so deep, we predicted geological structure through the analysis of amplitude features of seismic data. Characteristics of seabed sediments cold be obtained regionally and directly through combined analysis of marine geophysical survey data and coring data.

A Study on the Improvement of Marine Traffic System in the Ulsan Approaching Waters (울산항 접근수역의 항로지정에 관한 연구)

  • Jeong, Jae-Yong;Yoon, Dae-Gwun;Kim, Cheol-Seung
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.16 no.2
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    • pp.209-214
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    • 2010
  • This study examined environmental condition, marine accidental data, marine traffic capacity and traffic flow, and fisheries zone status near Ulsan approaching water area. A questionnaire survey of marine traffic system was conducted on experts and users, and new plan was proposed. On the basis of the responses of experts and users to questionnaire, the essential factor of navigation danger and the essential factor of collision risk as well as the improvement plans were proposed. More efficient navigational fairway was set up through this study.

Biomass Estimation with a Hydroacoustic Survey and the Shrimp Beam Trawl Fishery in Gwangyanh Bay in Summer (하계 광양만 주변 해역의 새우조망 어획조사 및 수산자원 음향조사)

  • Han, Inwoo;Oh, Wooseok;Park, Geunchang;Yoon, Euna;Lee, Kyounghoon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.52 no.3
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    • pp.288-297
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    • 2019
  • This study conducted a survey using a sampling inspection method and acoustic technique for continuous monitoring of useful organisms and non-commercial fish species distributed in the water of Gwangyang Bay, and evaluated the marine resources. In June, 2018, 38 species were caught in the shrimp beam trawl, comprising 3,594 marine organisms with a total weight was 65,415.3g. The acoustic survey showed that the nautical area scattering coefficient (NASC; $m^2/n.mile^2$) for the waters of Gwangyang Bay was highest in Transect 15 ($1,655.5m^2/n.mile^2$) and lowest in Transect 1 ($1.3m^2/n.mile^2$). The biomass was estimated to be 2,634.9 tons in the acoustic survey. This indicates that the acoustic survey method detected more fish shoals than the sampling inspection method.

Analysis of Biotechnology Companies' Needs Related to Supporting Their Entry into the Marine Biotechnology Industry (바이오 기업의 해양바이오 분야 진입을 위한 기업수요 분석)

  • Jang, Duckhee;Kang, Yerin;Oh, Chulhong;Doh, Soogwan
    • Ocean and Polar Research
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    • v.39 no.3
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    • pp.233-244
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    • 2017
  • This study seeks to analyze the needs of biotechnology companies in relation to their entry into the marine biotechnology industry and to discuss the policy implications associated with empirical tasks based on issues raised from empirical results gathered from a survey data of 200 biotechnology companies in Korea. This study made a comparison between marine and non-marine biotechnology companies and analyzed non-marine biotechnology companies' needs related to their entry into the marine biotechnology companies by using Social Network Analysis (SNA). Empirical results indicate that 23.5% of biotechnology companies produce goods using marine bio-resources. Once the utility of marine bio-resources is established, 58.8% of non-marine biotechnology companies intend to enter the marine biotechnology industry. This study also shows that non-marine biotechnology companies need technical support, information sharing, and the acquisition of raw materials to enter the marine biotechnology industry. The findings in this study provide important pointers for the direction of policies and future research in the area of marine biotechnology industry.

A Basic Study on the Fatigue Analysis Model for Marine Officers (항해사의 피로도 분석모델에 관한 기초연구)

  • Yang, Won-Jae
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.15 no.3
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    • pp.217-222
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    • 2009
  • Safe navigation is closely related to the fatigue of marine officers. Also, the fatigue of duty officer can cause serious marine accidents. In this study, the documentary survey about the marine officers' working environments, fatigue factors and symptoms was conducted. And the questionnaire survey which is related to the fatigue analysis factors such as sleepiness, mental physical workload and alcohol for apprentice officers was carried out, and the results of questionnaire survey were analyzed. Lastly, on the basis of this study, the fatigue analysis model was suggested in order to assess the marine officers' performance in the future.

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Marine Pollution of the East China Sea by Floating Marine Debris(I) - Temporal quantity distribution of each zone - (부유성 해양 폐기물에 의한 동지나해의 해양오염(I) - 해역별 수량 분포를 중심으로 -)

  • Kim, Jong-Hwa;Kim, Yong-Bok
    • 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.

Management after installation of artificial reefs;Present Condition and Development Scheme (인공어초 사후관리 현황과 발전방향)

  • Lee, Sung-Il;Ahn, Seung-Hwan;Kim, Dong-Sun
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2005.11a
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    • pp.160-161
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    • 2005
  • It is important to manage artificial fish reefs with installation for restoration. The instruments of survey for artificial reefs condition(location, amount etc.) is Side Scan Sonar and Multi-beam sonar. The efficient and economic survey of the artificial reefs facility is the complete survey of the SSS(Side Scan Sonar) in all area first and then the survey of the artificial reefs by MBES(Multi Beam Echo Sounder) in the finding area.

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