• Title/Summary/Keyword: Marine Police Development

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Relationship between the variation of the Tsushima Warm Current and current circulation in the East Sea (동해에서 potential vorticity와 해류순환과의 관계)

  • Lee Chung Il;Cho Kyu Dae;Yun Jong-Hwui
    • Proceedings of KOSOMES biannual meeting
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    • 2004.05b
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    • pp.89-92
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    • 2004
  • Potential vorticity is useful to illustrate mechanism and distribution pattern of current circulation the upper layer in the East Sea is divided into three part following like surface layer, Tsushima Warm Current(TWC) layer. Potential vorticity shows well the meandering of the TWC and polar front and circulation cell ill the northern part of polar front.

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Measurement of vertical migration speed of Sound Scattering Layer using an bottom mooring type Acoustic Doppler Current Profiler (해저설치형 음향도플러유향유속계를 이용한 음향산란층의 연직이동속도 측정)

  • Jo, Hyeon-Jeong;Lee, Kyoung-Hoon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.46 no.4
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    • pp.449-457
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    • 2010
  • This study shows that the vertical migration speed of sound scattering layers (SSLs), which is distributed in near Funka Bay, were measured by 3D velocity components acquired from a bottom moorng ADCP. While the bottom mooring type has a problem to measure the velocity vectors of sound scattering layer distributed near to surface, both the continuous vertical migration patterns and variability of backscatterers were routinely investigated as well. In addition, the velocity vectors were compared with the vertical migration velocity estimated from echograms of Mean Volume Backscattering Strength, and estimated to produce observational bias due to SSLs which is composed of backscatterers such as euphausiids, nekton, and fishes have swimming ability.

Occurrence and acoustic characteristics of finless porpoise (Neophocaena asiaeorientalis) off the south coast of Korea using hydrophone and visual surveys (패시브 음향조사와 목시조사를 통한 한국 남해안에 서식하는 상괭이 종(Neophocaena asiaeorientalis )의 출몰 및 음향 특성)

  • Hyunyoung KIM;Jihoon JUNG;Dongha KANG;Fredrich SIMANUNGKALIT;Myounghee KANG
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.60 no.3
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    • pp.258-268
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    • 2024
  • We presented foundational findings regarding the occurrence and acoustic characteristics of the finless porpoise through passive acoustic and visual surveys conducted on the southern coast of Korea, specifically at Hadong Jungpyeong Port. Over a survey period spanning from July 8 to August 16, 2023, totaling 40 days, we observed peaks in the number of clicks produced by this species on July 15, July 24, August 4, August 11, and August 16. The highest count, totaling 18,924 clicks, was recorded on July 15th, while the lowest count, at 3,888 clicks, occurred on August 8th. Examining the acoustic characteristics throughout the diurnal cycle, we found that the peak activity in terms of DPM (detection positive minute for one hour), DP10M (DPM for ten minutes), and overall number of click sounds was observed between 05:00 and 08:00, with a secondary peak occurring from 17:00 to 18:00. The quietest period was noted between 23:00 and 02:00. Furthermore, there was a significant increase in the number of clicks from sunrise, with the maximum count of 21,581 clicks recorded at 6 AM. This count gradually decreased until noon, experienced a slight increase thereafter, peaked again at sunset, and then declined. The dominant frequency mode of this species was 126 kHz, with a concentration ranging from 112 to 136 kHz. The average duration of a click sound was 127 ㎲, with approximately 16 sinusoids (cycles) within each click sound and an average cycle length of approximately 7.9 ㎲. These findings from our study are anticipated to serve as foundational data for the development of a Korean pinger and acoustic warning system.

Preconditioning phase for open ocean formation in the northern part of subpolar front of the East Sea (동해에서 외양대류에 의한 심층수 형성 초기단계의 특성)

  • Lee, Chung-Il;Kim, Dong-Sun;Kim, Sang-Woo;Yun, Jong-Hwui
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.11 no.1 s.22
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    • pp.77-82
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    • 2005
  • In order to investigate the initial stage of deep water formation between Vladivostok and the subpolar front in the East Sea, the factors, temperature, salinity, dissolved oxygen, measured by multi-ship surveys in ]969 have been used. Deep water formation in the .cast Sea occurs in essentially two different forms: near continent and open ocean formation. The position of eddy derived from potential vorticity matches well with that of deep water formation. The vertical and horizontal distributions of potential vorticity, geostrophic current, temperature, salinity and dissolved oxygen give clues for the preconditioning phase qf open ocean formation like a doming of isotherm, associated with a cyclonic circulation.

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Study on the Development of Social Evaluation Model for Aids to Navigation Accident (항로표지사고의 사회적비용 평가모델 개발에 관한 연구(I))

  • Moon, Beom-Sik;Gug, Seung-Gi;Lee, Young-Tae
    • Journal of Navigation and Port Research
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    • v.42 no.3
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    • pp.187-194
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    • 2018
  • Aids to Navigation (AtoN) is a marine traffic safety facility used to facilitate the safe and efficient movement of shipping and enhance the protection of the marine environment by the regulations or guidelines of The International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA). Our country is managing AtoN to provide consistent services for AtoN users, although an average of 141 AtoN accidents occur annually. An AtoN accident forces non-planned work on the managers to resort the function, and causes psychological anxiety for its users, ultimately resulting in economic losses. This study developed the Social Cost evaluation model of AtoN accidents. The model can be used to quantify the manager's economic activities related to the shutdown and recovery, as well as the cost associated with the inconvenience to AtoN users. The Social Cost evaluation model of AtoN accidents is proposed as the sum of the encounter cost, administration cost and risk cost.

Change of relative fishing power index from technological development in the offshore large powered purse seine fishery (근해대형선망어업에서 어로기술개발에 따른 어획성능지수 변동)

  • SEO, Young-Il;HWANG, Kang-Seok;CHA, Hyung-Kee;OH, Taeg-Yun;JO, Hyun-Su;KIM, Byung-Yeob;RYU, Kyong-Jin;LEE, Yoo-Won
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.53 no.1
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    • pp.12-18
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    • 2017
  • Lots of fishery stocks are overexploited and the overcapacity exists in Korean fishing fleets. One of the reasons is technological development, which increases the efficiency of the vessels continuously. The analysis was conducted to identify the change of fishing power index to develop the vessel and gear technology that may have improved the fishing efficiency of the offshore large powered purse seine fishery from 1960s to 2010s. Gross tonnage and horse power per fishing vessel was increased annually. Fishing gear material was changed to the knotless webbing to settle faster. Fishing equipments was modernized and supply rate was also increased. Therefore the relative fishing power index in the offshore large powered purse seine fishery increased from 0.4 in 1970 to 1.0 in 1980, to 1.5 in 2000 and to 1.6 in 2010, but the rate of increase slowed down gradually. The results are expected to contribute to reasonable fishery stock management.

A Study on the Marine Interests and Marine Force Theory (해양의 이익과 해양력에 관한 연구)

  • Yan, Tie-Yi;Kim, Sang-Goo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.18 no.3
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    • pp.227-233
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    • 2012
  • The oceans are the largest body of water geographical unit in the earth. In accordance with the general said of the international law, countries on the international law must have four elements: 1) settled residents; 2) determined territory; 3) a certain degree of government organizations; 4) the sovereignty. The country's basic rights are: 1) the right to independence; 2) the right to equal; 3) the right to jurisdiction; 4) the right to self-protection. UNCLOS as the only one of the "Constitution of the Earth" on the earth, the implementation of its entry into force make about 1/3 of the world's oceans should be assigned to the coastal states, in the use and management of ocean gave the coastal states the center jurisdiction, the coastal states' jurisdiction sphere had been expanded, the power comparison among all countries in the world had new changes. The ocean territory, like the land territory, is the most major material condition of a country. The ocean's strategic status is extremely important, is the important stage of the international political, economic and military struggle, there are many disputes about the rights and interests, resources and the development and utilization on the oceans. To resolve these disputes is bound to depend on a strong comprehensive national strength, including politics, economy, science and technology, as well as the powerful marine force, in which maritime police plays an important role.

Reviews on the Adaptation Strategy to Climate Change -Application to the Sea Level Rise- (기후변화 적응방안 연구 -해수면 상승을 중심으로-)

  • Cho Kwangwoo;Maeng Jun-Ho;Kim Hae-Dong;Oh Young Min;Kim Dong-Sun;Kim Mu Chan;Yoon Jong Hwui
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.10 no.2 s.21
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    • pp.81-88
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    • 2004
  • We review the adaptation strategies of the 21st climate change in an application to sea level rise. For the development of appropriate adaptation strategies on the coast vulnerable to the sea level rise, we have to consider the issues such as where to adapt, how to adapt, and when to adapt. The coastal target needed adaptation can be found by the evaluation of adaptive capacity of the coastal zone which requires the understanding of impacts and adaptive potential of the natural and socioeconomic systems in the coastal zone. Planned adaptation options to sea level rise can be classified into three generic approaches as managed retreat, accommodation, and protection In practice, the implementation of the options requires the analysis of land use, degree of vulnerability, cost and benefit, etc, and may be combination of the options rather than one approach. In terms of the response timing, the adaptation can be grouped as anticipatory and reactive ones. Generally it is more effective to consider both anticipatory and reactive adaptations at the same time for the impacts of future sea level rise. Due to the scientific uncertainty of climate change issues including sea level rise, the adaptation processes have to be designed to deal with a series of processes such as information md awareness establishment, planning and design implementation, and monitoring and evaluation in continuity and long-term period.

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