• Title/Summary/Keyword: reef

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The study on the Base point and baseline in Korea, Japan, and China (한반도 주변의 영해기점 및 기선에 관한 연구 - 한국, 중국, 일본을 중심으로)

  • Kim, Baek-Su;Choi, Yun-Soo;Park, Byung-Moon;Jeon, Chang-Dong
    • 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.

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Assemblage changes of benthic foraminifera and regional paleoenvironmental changes in a piston core from the Okinawa Trough, Japan (오끼나와 해곡 주장사료 퇴적물에 대한 저서생 유공충의 군집변화와 지역해 고환경변화)

  • Hyun, Sang-Min
    • The Korean Journal of Quaternary Research
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    • v.23 no.2
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    • pp.48-55
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    • 2009
  • To investigate the paleoceanographic environmental changes around the Okinawa Trough, Japan, a piston core (RN88-PC5) was conducted on benthic foraminiferal species composition, assemblage, sedimentological and geochemical analyses. Trubidite sediment intercalated in studied core contains different benthic foraminiferal species, dwelling in shallow coral reef species, from normal hemipelagic sediment. These different benthic foraminiferal species and its assemblage are interpreted as reworked sediment when turbidite current occurred, synchronically. Grain size analysis clearly showed that mean grain size difference occurred between trubidite and hemipelagic sediments. Geochemical analysis also showed the difference of chemical composition between two sedimentary facies. Results of the foraminiferal oxygen isotope analysis showing global surface water warming records since the last 10 ka. The geochemcial analysis and previous works showed that turbidite sediment of studied core indicating sporadic occurrence of regional paleoceanographic events. Assemblage of shallow coral reef benthic foraminifera especially occurred with turbidite layer clearly support the sporadic occurrence of paleoceanographic events such as regional earthquake.

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Comparison of Ocean Optical Properties Between the Micronesia and the Korean Peninsula (남태평양 마이크로네시아와 한반도 주변 해역의 해수 광학특성 비교)

  • Moon, Jeong-Eon;Choi, Jong-Kuk
    • Korean Journal of Remote Sensing
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    • v.37 no.5_1
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    • pp.1125-1133
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    • 2021
  • This study attempted to understand seawater characteristics like chlorophyll concentration (CHL), total suspended matter concentration (TSM), absorption characteristics, and remote sensing reflectance around Weno Island, Micronesia, located in the South Pacific Ocean near the equator. 50 in-situ measurement from May to June 2013 were analyzed and compared with data from around Korean peninsula. CHL around Weno Island was 0.11-0.49 mg/m3 (average 0.26 mg/m3), and TSM was 0.03-0.31 g/m3, (average 0.16 g/m3), showing typical clear water characteristics. Absorption coefficient of total suspended matters at 443 nm showed over 0.5 times less than that from East Sea and the slope of absorption coefficient spectrum of dissolved organic matter showed much larger than that of Korean peninsula, indicating the concentration of organic matter is very low and dissolved organic matter of marine origin is considered to be the main component in the study area. As a result of comparing the remote sensing reflectance spectrum with that of coastal waters around the Korean peninsula, coastal waters around Weno Island showed typical CASE-1 water properties. It was possible to understand the marine optical characteristics of coral reef habitats in tropical waters, and it can be used to develop seawater algorithms specialized in the study area.

A Study of Algal Succession and Community Structure on Artificial Reef at Yangyang-gun and Pohang-si, Korea (양양군과 포항 해역에 시설한 인공어초에서 진행된 해조천이와 군집에 관한 연구)

  • Lee, Hyeon Jin;Choi, Chang Geun
    • Journal of Marine Life Science
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    • v.4 no.2
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    • pp.81-85
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    • 2019
  • This study was carried out to observe the changes of seaweed community in artificial reefs installed in September, 2016 in Namae-ri, Yangyang-gun, and Seokbyeong-ri, Pohangsi, Korea. Field surveys were conducted by SCUBA diving once a season in February, May, August, and November of 2017, and quantitative survey and qualitative survey were carried out in parallel. In this study, a total of 94 species, including 11 green algae, 15 brown algae and 68 red algae were appeared. 66 species (8 green algae, 9 brown algae, 49 red algae) and 65 species (7 green algae, 9 brown algae, 49 red algae) were collected and identified in Yangyang and Pohang. In dominant species, Yangyang was dominant species of Saccharina japonica and subdominant species of Ulva australis. Pohang dominated in order of Colpomenia sinuosa and Gelidium elegans. In both coastal areas, Ulva spp., Colpomenia sinuosa were grown at the early stage of reforestation, and perennial seaweeds such as Saccharina japonica, Ecklonia cava and Gelidium elegans were grown. In order to clarify the clustering relation through flora change, it is necessary to monitor the transition process until the seaweed community is stabilized by observing the long-term change through continuous monitoring.

Commercial fishery assessment of Malaysian water offshore structure

  • Mohd, Mohd Hairil;Thiyahuddin, Mohd Izzat Mohd;Rahman, Mohd Asamudin A;Hong, Tan Chun;Siang, Hii Yii;Othman, Nor Adlina;Rahman, Azam Abdul;Rahman, Ahmad Rizal Abdul;Fitriadhy, Ahmad
    • Fisheries and Aquatic Sciences
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    • v.25 no.9
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    • pp.473-488
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    • 2022
  • To have a better understanding of the impact of the PETRONAS oil and gas platform on commercial fisheries activities, Universiti Malaysia Terengganu (UMT) examined two approaches which are data collection from satellite and data collection from fishermen and anglers. By profiling the anglers who utilize reefed oil and gas structures for fishing, it can determine if the design and location of the reef platforms will benefit or negatively impacts those anglers and fisherman. Furthermore, this assessment will be contributing to the knowledge regarding the value of offshore oil and gas platforms as fisheries resources. Collectively, the apparent fishing activity data included, combined with the findings in the reefing viability index will help to inform PETRONAS's future decommissioning decisions and may help determine if the design and proposed locations for future rigs-to-reefs candidates would benefit commercial fishing groups, further qualifying them as appropriate artificial reef candidates. The method applied in this study is approaching by using a data satellite known as Google's Global Fishing Watch technology, which is one of the applications to measure commercial fishing efforts around the globe. The apparent commercial fishing effort around the selected twelve PETRONAS platforms was analyzed from January 2012 to December 2018. Using the data collection from fishermen which is the total estimation of commercial fish value cost (in Malaysia ringgit, MYR [RM]) in Peninsular Malaysia Asset, Sabah Asset, and Sarawak Operation region. The data were extracted every month from 2016 to 2018 from the National Oceanic and Atmospheric Administration database. Most of the selected platforms that show a high frequency of vessels around the year are platform KP-A, platform BG-A and platform PL-B. The estimated values of commercial fishes varied between platforms, with ranged from RM 10,209.92 to RM 89,023.78. Thus, platforms with high commercial fish value are selected for reefing in-situ and will serve multi-purposes and benefit the locals as well as the country. The current study has successfully assessed the potential reefing area of the Malaysian offshore environment with greater representativeness and this paper focused on its potential as a new fishing ground.

Scouring and accumulation by tidal currents around cubic artificial reefs installed at Geogeom waterway (거금수로에 시설된 사각형 인공어초 주변의 조류에 의한 세굴 퇴적 변화)

  • Kim, Dae-Kweon;Lee, Jin-Young;Suh, Sung-Ho;Kim, Chang-Gil;Cho, Jea-Kwon;Cha, Byung-Yul
    • Journal of Advanced Marine Engineering and Technology
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    • v.33 no.8
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    • pp.1275-1280
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    • 2009
  • Tidal currents were observed at 1 station of artificial reefs group during 15days. Maximum current was 82.4cm/s, and mean current showed 12.8~28.0cm/s, respectively. Flood currents magnitude were bigger than ebb ones due to wake region. To grasp sediment distributions, sediments were sampled at 4-direction(E, W, S, N) around each station. According to the results of sample analysis, sediments showed different distribution by main current direction. It showed that sediments distribution at front and back of artificial reefs were differently occurred by change of main current direction. It suggest that artificial reefs need to install after confirming tidal currents direction and sediments type.

Who Leads Nonprofit Advocacy through Social Media? Some Evidence from the Australian Marine Conservation Society's Twitter Networks

  • Jung, Kyujin;No, Won;Kim, Ji Won
    • Journal of Contemporary Eastern Asia
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    • v.13 no.1
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    • pp.69-81
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    • 2014
  • While much in the field of public management has emphasized the importance of nonprofit advocacy activities in policy and decision-making procedures, few have considered the relevance and impact of leading actors on structuring diverse patterns of information sharing and communication through social media. Building nonprofit advocacy is a complicated process for a single organization to undertake, but social media applications such as Facebook and Twitter have facilitated nonprofit organizations and stakeholders to effectively share information and communicate with each other for identifying their mission as it relates to environmental issues. By analyzing the Australian Marine Conservation Society's (AMCS) Twitter network data from the period 1 April to 20 April, 2013, this research discovered diverse patterns in nonprofit advocacy by leading actors in building advocacy. Based on the webometrics approach, analysis results show that nonprofit advocacy through social media is structured by dynamic information flows and intercommunications among participants and followers of the AMCS. Also, the findings indicate that the news media and international and domestic nonprofit organizations have a leading role in building nonprofit advocacy by clustering with their followers.

PIV measurement on flow characteristics behind a Tetrapod in uniform flow (균일 흐름에 놓인 테트라포드 후류 유동특성에 대한 PIV 계측)

  • Gim, Ok-Sok;Lee, Kyeong-Woo
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.44 no.3
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    • pp.207-217
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    • 2008
  • Costal regions in Korea often suffer severe damages due to wave-induced disasters, storm surge disasters and so on. therefore, many engineers and researchers have devoted their energy to prevent these costal disasters. The development of artificial reefs including sunken vessels is one of their remarkable achievements and various kind of these artificial upwelling structures have been designed and applied. However, the flow characteristics around a Tetrapod under the water has not been investigated experimentally. So in this article, in uniform flow of circulating water channel and some different velocities, PIV measurement has been conducted on the flow characteristics behind a Tetrapod. The results were analyzed on the flow characteristics of both cases of a Tetrapod. Therefore, it can be concluded that the both cases have its own distinctive flow characteristics behind the bluff body; Case A has an steep upstream flow pattern. On the contrary, Case B has an developed downstream flow pattern in the near wake of the Tetrapod. The velocity gradient at position x=150mm of Case-A appears gently up and down But, the velocity gradient at the same position of Case-B appears better highly up and down.

Accuracy of Close-Range Industrial Photogrammetry Using CCTV Type CCD Camera (CCTV유형 CCD 카메라를 이용한 근거리 산업사진측량의 정확도)

  • 이진덕;최용진
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.19 no.3
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    • pp.283-290
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    • 2001
  • This paper demonstrates the performance of industrial precise measurement using the digital close-range photograrmmetric system based on a off-the-shelf CCTV-type CCD camera. The system was constructed with a CCD camera and a PC with a frame grabber, coupled with digital image mensuration and self-calibrating bundle adjustment techniques. An artificial fish reef with cubic shape was taken as an object for the application test of the system and the digital images were acquired on multi-station convergent network around the object. The geometric calibration of the CCD camera and the phototriangulation of the entire surface of the object was carried out simultaneously by means of self-calibrating bundle adjustment technique. Also the system comprising a high resolution still-video camera Kodak DCS, which high accuracy potential has been already established, were employed in similar network condition. Then the results from two different camera systems were compared in the accuracies of phototriangulation.

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The Legal Improvement to turn a Fishery Facility to Tourism Resources (수산시설의 관광자원화를 위한 법 제도적 개선방안 - 수산종묘 생산시설, 인공어초와 방파제를 대상으로 -)

  • Lee, Seung-Woo
    • The Journal of Fisheries Business Administration
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    • v.38 no.3
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    • pp.25-51
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    • 2007
  • Recently those who visit a fishing village is increasing. So the government's policymaker is interested in a tourism of fishing village. There are a lot of local governments that they turn it to good account to activate the fishing community. So they plan for the tourism facility in the fishing village and invest in it. The fishery facility can playa role in it. Nonetheless it is not playing a role in tourism facility. Though the breakwaters projecting far into the sea are good waterfront, most of them are not reflecting the function of it. And fishery facility producing seed is a good resource of eco-tourism, but it is yet a tourist potential. Although the artificial reef is going far toward promoting a fishery resource, it is seldom used as a tourism resource. The multiple functions of fishery facilities have to be improved to raise the investment effect of them. Especially the tourism function has to be added on their basic function. The multiple functions of fishery facilities is necessary to satisfy tourist's needs. In results, not only their value but also value of fishing village will be raised.

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