• Title/Summary/Keyword: Marine Survey

Search Result 1,253, Processing Time 0.023 seconds

Marine Seismic Survey using a Multi-source System (다중음원을 이용한 다중채널 해양 탄성파 탐사)

  • Kim, Hyun-Do;Kim, Jin-Hoo
    • Proceedings of the Korean Society of Marine Engineers Conference
    • /
    • 2006.06a
    • /
    • pp.209-210
    • /
    • 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(1.5 kHz) for high frequency source.

  • PDF

A Study on Determinations of Survey Station in Marine Ecosystems Based by Impact Prediction of Environment Impact Assessment in Coastal Development Projects (연안개발사업 환경영향평가 영향예측 결과에 근거한 해양생태계 조사정점 선정방안에 관한 연구)

  • Cho, Beom-Jun;Maeng, Jun-Ho
    • Journal of Environmental Impact Assessment
    • /
    • v.21 no.5
    • /
    • pp.767-779
    • /
    • 2012
  • In case of executing surveys in marine ecosystems, the most important things are scientific selection measures of survey stations that can represent various ecosystems characteristics in subjected areas. The situations show a lot of differences that understand characteristics of marine ecosystems in targeted areas according to selection methods and positions in survey stations. Investigation ranges and station numbers in marine ecosystems are classified according to project characteristics and scales. But, currently a clear divisions or objective standards are not. Therefore, this study tried to provide selection measures of survey station in scientific and objective marine ecosystems through precise analysis among environmental impact statements of coastal development projects until now. In this study, impact scopes of marine ecosystems correspond to physical impact predictions by undertaking projects. Impact ranges were divided into three(physical impact ranges) coastal waters. In case of proposing numbers of survey stations according to this survey ranges, numbers of investigation stations due to minimum survey scopes in targeted projects applied 20~30% of all numbers in survey stations. Number of survey stations due to average investigation scopes within physical impact ranges applied 60~70% of all numbers in investigation stations. Numbers of survey stations due to maximum survey ranges within physical impact scopes applied 10~20% of all numbers in survey stations. So, improvement measures were deducted. Finally, according to prediction ranges in impact of various coastal development projects, several kinds of conclusions are suggested. And, it is thought to be able to use as fundamental database to select investigation stations in marine organisms through this study.

Improvement of the EIA for Land Reclamation Projects in the Coastal Areas of Korea (해양매립사업 환경영향평가의 개선방안)

  • Jang, Ju-Hyoung;Eom, Ki-Hyuk;Kwon, Kee-Young;Hong, Sok-Jin;Park, Jae-Hyeon;Kim, Gui-Young
    • Journal of Environmental Science International
    • /
    • v.16 no.7
    • /
    • pp.847-853
    • /
    • 2007
  • In Korean coastal areas, land reclamations are main development projects that should be based on environmental impact assessment(EIA), because those human interventions can change coastlines, damage tidal flats, and pollute adjacent areas to threat seafood safety and devaluate overall ecosystem service value. Existing procedures of the EIA for land reclamation projects were diagnosed and evaluated to enhance them. Problems were identified in the designation of survey areas, the consistency in survey sites and periods, the standardization of survey methods and reports, the confidence of survey results and the verification of predictions. Lack of integration was noticeable and could be improved by synthesizing different assessments from topography geography, marine physics, marine chemistry and marine biology. We suggest that successful precautionary marine environment management requires readjusting the cost of EIA, recruiting experts in marine environment, constructing database and establishing specialized assessment system.

Recognize Survey for Founding of the Department of Marine Leisure Industry in Fisheries High School (수산계고 해양레저산업과 신설에 대한 인식 조사)

  • Park, Jong-Un;Kim, Yeung-Hoon;Kang, Beodeul;Won, Hyo-Heon
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.27 no.2
    • /
    • pp.556-565
    • /
    • 2015
  • The purpose of this study is to research on founding of the department of marine leisure industry in fisheries high school. Research methods were used a survey district, students and teachers in fisheries high school and industry human are 353 people in the target. The results of this research are as follows. First, the ratio in favor of making the marine leisure industrial department had more than 81%. The second, teachers and industry people selected core factors include oceanography, water leisure, leisure diving, commercial diving, lifeguard, rafting. Finally, subject for the department of marine leisure industry in fisheries high school are fisheries shipping industry basis, understanding of the ocean, marine leisure tourism, underwater technology, navigation, seamanship, maritime laws regulations, heat engines and aquatic organism.

A Study on the Integrated Seismic Reflection and Refraction for Shallow Marine Site Survey KSEG.KGS Joint Symposium (천해저 조사를 위한 탄성파 반사법 및 굴절법 통합연구)

  • Kim, Chan-Su;Lee, Sang-Chul;Shin, Sung-Ryul;Kim, Hyun-Do;Jo, Chul-Hyun
    • 한국지구물리탐사학회:학술대회논문집
    • /
    • 2007.06a
    • /
    • pp.349-352
    • /
    • 2007
  • Estimating the physical properties of the survey area and mapping the geotechnical basement play an important role in ocean engineering and construction field. In this study, we performed marine seismic reflection and refraction survey as an engineering application at shallow marine. We made use of the dual boomer - single channel streamer as a source-receiver in reflection seismic survey and air-gun source - the manufactured OBC(Ocean Bottom Cable)-type streamer in refraction survey. In the seismic reflection data, we could easily find the geological layers and basement. Moreover, seismic refraction data could present sediment thickness and velocity distribution.

  • PDF

Spatial characteristics of fish distribution lured by artificial reefs in Jeju marine ranching area (제주 바다목장 해역의 인공어초에 유집된 어군 분포의 공간적 특성)

  • Hwang, Bo-Kyu;Jang, Ho-Young
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.50 no.1
    • /
    • pp.30-38
    • /
    • 2014
  • Hydro-acoustic survey was carried out to investigate the spatial characteristics of fish distribution near two artificial reefs (AO: large octagonal semi-sphere and AC: combined custom built) having different types in Jeju marine ranching area. The survey system consisted of scientific echo sounder (EK60), DGPS system, and ECDIS (Mecys). Field survey was conducted on August and October 2012 with star survey and line transect survey line method, and species composition was investigated from gill net fishing survey. The acoustic signals from individual fishes and small fish schools were mainly recorded around AO, but large and strong signals from large fish school were mainly detected in the top layer of and the water column near AC. The echogram suggest that the fish aggregation for the two types of AO and AC exist the significant difference in fish species and spatial distribution pattern.

Hydro-acoustic survey on fish distribution and aggregated fish at artificial reefs in marine ranching area (음향조사기법을 이용한 수산자원 관리수면의 어류분포 및 인공어초지역의 어군위집조사)

  • Kim, Hyun-Young;Hwang, Bo-Kyu;Lee, Yoo-Won;Shin, Hyeon-Ok;Kwon, Jung-No;Lee, Kyung-Hoon
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.47 no.2
    • /
    • pp.139-145
    • /
    • 2011
  • Hydro-acoustic survey was carried out to estimate a fish distribution at marine ranching area and aggregated fish schools at artificial reef area in Oeyeondo, Korea. The survey system was set up with DGPS system, scientific echo sounder (EK60, Simrad Co.), and ECDIS (Mecys. Co. LTD). A track survey and a random survey was respectively applied to the marine ranching area (474.4ha) and to the artificial reef area (within a radius of 300m). As the result, fish distribution and MVBS values in marine ranching area showed that created fisheries resources didn't come to be abundant yet as to appear fish distribution in all of the area. In the artificial reef area, it was, however, able to detect many fish school signals on the top of and around artificial reefs and to confirm the luring effect of artificial reefs.

Survey Research Analysis for Enhancing the Utilization Level of Marine Meteorological Information (해상기상정보의 활용도 향상을 위한 설문조사분석)

  • Park, Jong-Kil;Jung, Woo-Sik;Kim, Eun-Byul;Choi, Su-Jin
    • Journal of Environmental Science International
    • /
    • v.20 no.9
    • /
    • pp.1095-1104
    • /
    • 2011
  • A survey of professionals employed in marine related fields was conducted on subjects related to marine meteorological forecasts and special reports. The outcome of the survey indicated that the respondents were overall satisfied with the determination of the zones related to marine meteorological forecasts and special reports and with the number of forecast factors, but in regards to the questions about specific adjustment methods, it was found that the respondents perceived a need for adjustment. In addition, although there was a high consensus among the respondents that the criteria for watch and warning in the marine special reports were suitable, they voiced the opinion that it will be necessary to implement changes in the current criteria for watch and warning in order to further improve the compatibility of the criteria. The survey found that there was a high level of utilization for the marine meteorological information provided by the Korea Meteorological Administration(KMA), and that respondents mostly acquired this information via internet and TV. On the other hand, however, the satisfaction level regarding the accuracy of the marine meteorological information was low in comparison to the utilization level. The survey regarding areas for improvement in the forecasts and special reports also indicated that the need for 'improvement in the accuracy of forecasts' was cited most frequently.

Analysis on the Results of Fatigue Survey for Marine Officers (해기사의 피로도 현황에 대한 조사 분석)

  • Yang, Won-Jae
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.18 no.6
    • /
    • pp.551-556
    • /
    • 2012
  • Fatigue is known to detrimentally affect a person's performance. Also, fatigue may reduce effectiveness and efficiency of marine officers and crew members. The purpose of this research is to understand on the status of the marine officers' fatigue. In this study, we carried out the questionnaire survey which is related to the marine officers' fatigue factors such as work, sleep and rest hour or period, sleepiness, casual factor, fatigue symptom, etc. The questionnaire contained 25 questions and it was distributed among 1,033 marine officers(deck officers 607 and engineers 426). The results of this survey show that marine officers' fatigue is a casual factor in marine accidents such as collisions, groundings and there was a fatigue difference between deck officers and engineers.

High-resolution Shallow Marine Seismic Survey by Using a Multi-channel Seismic System (다중채널을 이용한 천해저 고해상 해양 탄성파탐사)

  • Kim, Hyun-Do;Kim, Jin-Hoo
    • Proceedings of the Korean Society of Marine Engineers Conference
    • /
    • 2005.06a
    • /
    • pp.757-763
    • /
    • 2005
  • A multi-channel seismic system has been developed and applied for bedrock mapping in near shore environment. The system is composed of an analog signal processor and an A/D converter installed on the computer, and a streamer with the group interval of 5 meters. The system is accomplished with a data acquisition program which controls the system and a data processing software. With the PC-based shallow marine seismic survey system high-resolution 2-D marine seismic profiles which have high S/N ratios can be obtained after appropriate data processing.

  • PDF