• Title/Summary/Keyword: South sea

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The opening efficiency of the miniaturized small-scale net for anchovy boat seine to reduce the fleet size (선단축소를 위한 기선권현망 축소형 소형어구의 전개성능)

  • AN, Young-Su;BACK, Young-su;JIN, Song-han;JANG, Choong-Sik;KANG, Myoung-hee;CHA, Bong-jin;CHO, Youn-hyoung;CHA, Ju-hyeng;KIM, Bo-Yeon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.55 no.1
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    • pp.7-19
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    • 2019
  • This study was conducted in order to improve opening efficiency of the miniaturized small-scale net for anchovy boat seine gear to reduce the fleet size. Field experiment was performed to observe geometry of nets by catcher boats. When the distance between the two ships was 150, 300 and 450 m and the speed of towing nets was 0.6, 0.9, and 1.2 kt, the vertical opening and actual opening of each part of the miniaturized small-scale net was as follows: the front part of the wing net, 6.8-9.5 m, 45-63%; the middle part of the wing net, 16.1-30.7 m, 34-65%; the entrance of the inside wing net, 21.6-41.2 m, 44-84%; the square and bosom, 17.4-34.0 m, 38-75%; the entrance of the body net, 16.5-29.4 m, 36-64%; the entrance of the bag net, 14.5-21.9 m, 70-106%; the flapper, 6.7-7.7 m, 81-83%, and the end of the bag net, 8.6-10.9 m, 64-81%. The tension of towing nets was measured to be 2,734-6,812 kg approximately, which indicates that the fleet can tow nets with 350 hp, the standard engine horse power. The fishing operation time was shortened comparing to existent net with the large-scale buoy attachment operation. It was also possible to operate the ship without fish detecting boat.

Characteristics of Natural Habitats of Rare Species, Tofieldia nuda (희귀식물 꽃장포의 생육환경 특성)

  • Kwon, Soonsik;Hwang, In-Soo;Park, Wan-Gun;Cheong, Eun Ju
    • Korean Journal of Environment and Ecology
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    • v.33 no.1
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    • pp.86-106
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    • 2019
  • We investigated the environmental conditions of natural habitats of T. nuda. The species was found on rocky northern hills ($60{\sim}90^{\circ}$) near the stream where the sea level ranges 95~145m. The average annual temperature of the habitats was lower than other places of South Korea. The differences of the lowest and the highest of the year was significantly huge than any other places. Plants were growing at the edge of stream that water reached but not submerged. Most of plants were found in North, Northeast or Northwest. It is suggested that these species require moist and low sunlight for growth. The common vegetation along with the T. nuda includes Mukdenia rossii, Selaginella rossii, Calamagrostis epigeios, and Rhododendron yedoense f. poukhanense. The dominance values and sociability of T. nuda were below 3 in all studied habitats and the variance of the number of individuals among the habitats was very high. As the optimum habitats for the T. nuda are decreasing due to the extreme precipitation patterns. It is also expected that the number of T. nuda will be decreased in the future. Therefore restoration activity in situ or ex situ must be conducted to conserve this valuable plant species.

A Scheme for listing on FAO GIAHS and Preservation of Juk-Bang-Ryeum in the Southern Coast of Korea (남해안 죽방렴의 세계중요농어업유산 등재 및 보존 방안)

  • Lee, Kyung-Joo;Kwon, Hojong;Jeong, Dae-Yul
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.9 no.4
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    • pp.325-336
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    • 2019
  • There are many bamboo weir (Juk-Bang-Ryeum) with the highest preservation value as a fisheries heritage from Sacheon to Namhae area in the Korea Hanrye National Marine Park. It was designated as a Korea National Cultural Property Sightseeing No. 71, and also as an important fishery asset listed in the Korea National Important Fisheries Heritage No. 3. It is an important cultural heritage that should be preserved for the future as a community asset to the local residents, and should be preserved as it's original form because of unique traditional fishery style in the world as well as natural environment oriented fishing system. The purpose of this study is to review the value of Juk-Bang-Ryeum in the South Sea as well as to preserve the tradition of it. This paper will make a contribution to the registration of it on the list of World Important Agricultural and Fishery Heritage (GIAHS), which is recognized by the United Nations Food and Agriculture Organization (FAO). To make basic data for listing on it, we will analyze the characteristics and structure of Juk-Bang-Ryeum, and also research the value of it from the historical literature review as well state of arts. We also develop a scheme for listing on FAO GIAHS through checking necessary items step by step. Finally, we suggest some idea to preserve it more effectively.

A Study on the Evaluation of Coastal Shipping's Centrality Using a Social Network Analysis (SNA를 활용한 연안해운 중심성 평가에 관한 연구)

  • LEE, Hae-Chan;Park, Sung-Hoon;Yeo, Gi-Tae
    • Journal of Digital Convergence
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    • v.19 no.2
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    • pp.69-81
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    • 2021
  • Coastal shipping performs a pivotal role as a national transportation network and is highly valuable in terms of enabling more economical transportation at affordable prices than road transportation. In this regard, this study aimed to examine changes in the characteristics and centrality of South Korea's costal shipping sea-route networks by analyzing the centrality of domestic coastal shipping. To this end, social network analysis was used as an analysis technique that enables an analysis on the characteristics of coastal shipping networks. As a result, Jeollanam-do showed the highest degree centrality, ranking first in both the in-degree and the out-degree. Jeollanam-do also exhibited the highest betweenness centrality, and Gangwon-do registered the highest closeness centrality. In terms of hub and authority centrality, Jeollanam-do topped the list, followed by Gyeongsangnam-do and Gangwon-do in order. Lastly, Jeollanam-do ranked highest in the hub index, followed by Incheon, other regions, and Gangwon-do in order. This study is significant for suggesting the cities and provinces that play a key role in coastal shipping each year and their corresponding items. Future studies are recommended to identify the trend of coastal shipping through more detailed research on each port by city and province.

The effect of starvation on the characteristics of morphometric measurement and body-sectioned shape in Far Eastern catfish (Silurus asotus) (메기(Silurus asotus) 기아 시 외부형태 및 체 절단면 변화)

  • Park, In-Seok;Goo, In Bon;Gil, Hyun Woo
    • Korean Journal of Environmental Biology
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    • v.39 no.1
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    • pp.55-67
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    • 2021
  • A 210-day experiment was conducted to examine the effects of starvation on survival, external morphometric traits, and sectioned morphometric traits in Far Eastern catfish(Silurus asotus). The survival rate decreased to 92.2±0.47% in the fed group and to 74.4±2.59% in the starved group. Eight dimensions of Ls, DALPO/Ls, DADOP/Ls, ED/Ls, CH/Ls, BDAA/Ls, BDMA/Ls, and BWAA/Ls showed significant differences (p<0.05), and 16 other dimensions of DALAD/Ls, DPDPL/Ls, HPLAA/Ls, HALAV/Ls, HALOP/Ls, DAUPO/Ls, DADAV/Ls, DADAA/Ls, Max BL/Ls, Man BL/Ls, LD/Ls, HWOP/Ls, DAUF/HL, DAUS/HL, IW/HL, and DAUE/HL were not significantly different among the initial, fed, and starved groups (p>0.05). The fed group showed higher total height (THX), wider width (WX), and larger area (AX) than those of the starved group in each body section. This research provides information on the morphometric traits and body sections of starved Far Eastern catfish. These results can be used as a basic guide to indicate nutritional status and assist in aquaculture methods for Far Eastern catfish. Moreover, the methods used in this study were considered helpful because the survey analysis method can be used to investigate information on the nutritional status of other fish species.

Distribution of benthic organisms and growth and obesity of mussels (Mytilus coruscus) by depth in Geomundo, south coast of Korea (한국의 남해 거문도해역에 자생하는 홍합(Mytilus coruscus)의 수심별 성장, 비만도와 저서생물의 분포)

  • Bai, Jong Il;Hwang, Sung Il;Jung, Yeong Ho;Kim, Yu Jin;Kim, Dong Wook
    • Korean Journal of Environmental Biology
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    • v.39 no.1
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    • pp.19-31
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    • 2021
  • We investigated the distribution characteristics of mussels (Mytilus coruscus) growing in the Geomundo sea area by water depth. The research was also conducted to identify the surrounding benthic organisms. Mussels showed high density and low obesity in low water depths. The lower the density, the higher the obesity level appeared in deeper water. The morphological characteristics also appeared to increase as the water depth deepened. In addition, the shell length and total weight were more strongly correlated at a depth of 12 m than at 2 m. The total weight by the growth of the shell length and shell height was affected by the water depth. The analysis showed that the density and biomass of the algae inhabiting the surroundings decreased somewhat as the water depth increased. In benthic animals, the number of mussels tended to decrease slightly at the point where oysters dominated, at a depth of 2 m. Conversely, the number of oysters tended to decrease in deeper water dominated by mussels. Thus, the spatial competition between oysters and mussels was affected by the water depth. Also, mussels did not appear in areas where large algae flourished, suggesting that the survival of mussels was affected by the presence or absence of large algae.

Performance Assessment of Navigation Seakeeping for Coastal Liquified-Natural-Gas Bunkering Ship (연안선박용 LNG 벙커링 전용선박의 내항성능 평가에 대한 연구)

  • Yi, Minah;Park, Jun-Bum;Lee, Chang-Hee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.7
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    • pp.904-914
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    • 2020
  • Through the Ministry of Trade, Industry, and Energy, South Korea is trying to support the "Building Project for Liquified Natural Gas (LNG) Bunkering Ship," centered on the Korea Gas Corporation, while the Ministry of Maritime Af airs and Fisheries is pushing to construct an LNG bunkering terminal at Busan New Port. LNG bunkering ships are essential for supplying LNG fuel from the terminal to the ships, resulting in the need for safety operation procedures. Therefore, in this study, the stability of a coastal LNG bunkering ship operating from Busan New Port to the anchorage in Busan Port was assessed to investigate the need for operational procedures for coastal LNG bunkering ships. Seakeeping analysis of the LNG bunkering ship was performed for each significant wave height by combining the response amplitude operator from the ship motion analysis under the potential flow theory with the actual observed sea data for five years and Texel, Marsen, and Arsloe (TMA) spectrum suitable for the Busan coast. The results showed that the roll and horizontal acceleration were the main risks that affected the navigation seakeeping performance above a significance wave height of 2 m. The operational periods of the LNG bunkering ship ranged from 83.3% to 99.9% of the total observation period.

Research on the Necessity of Building the Second Space Rocket Launching Sites for Breakthrough Development of R.O.K National Space Power (도약적 국가 우주력 발전을 선도할 제2 우주센터 구축 필요성 연구)

  • Park, Ki-tae
    • Journal of Space Technology and Applications
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    • v.2 no.2
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    • pp.146-168
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    • 2022
  • Witnessing current military conflicts in South China Sea and Eastern Europe, most defense analysts evaluate one of the most serious security threat toward the US is coming from the superpower competitions with Russia and China. The main means for such super power hegemonic competitions is military power and space power is a key enabler to maximize the efficiency and effectiveness of military employment. Reflecting above circumstances, the space hegemonic competition between the Unites States and China is spreading into all aspects of national powers. Under such an environment, R.O.K needs to significantly develop national space power to preserve life and assets of people in space. On the other hand, the R.O.K has a lot of limitations in launching space assets into orbits by land-based space rockets due to its geographic locations. The limitation of rocket launching direction, the failure to secure a significant area enough to secure safety and the limitation to secure open area enough to build associated facilities are among them. On this paper, I will suggest the need to build the 2nd space rocket launching site after analyzing a lot of short-falls the current 'Naro' space center face, compared to those of advanced space powers around the world.

Multimodal Route Selection from Korea to Europe Using Fuzzy AHP-TOPSIS Approaches: The Perspective of the China-Railway Express (한-유럽 복합운송 경로선택에 관한 연구 중국-유럽 화물열차를 중심으로)

  • Wang, Guan;Ahn, Seung-Bum
    • Journal of Korea Port Economic Association
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    • v.37 no.4
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    • pp.13-31
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    • 2021
  • Since the signing of the Korea-Europe Free Trade Agreement, the volume of trade transactions between South Korea and Europe has increased. The traditional single-mode transport system has been transformed into an intermodal transport system using two or more modes of transport. In addition, the conventional sea and air transport routes have been restricted, leading to a decline in Korean exports to Europe, and the rail transport mode is becoming mainstream in the market due to the influence of COVID-19. This paper focuses on the China-Railway Express to explore a new intermodal transport route from Korea to Europe. First, the fuzzy analytic hierarchy process (AHP) is used to evaluate the factor weights when selecting intermodal transport routes from Korea to Europe. Then, the TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) method is used to rank three alternatives. The results show that among the four factors (total cost, total time, transportation capability, and service reliability), the total cost is the most significant factor, followed by the total time, service reliability, and transportation capability. Furthermore, the alternative route 1 (Incheon-Dalian-Manchuria-Hamburg) is preferred.

Toxic Effects on Lethal Concentration 50%, Heamatological Parameters and Plasma Components of Crucian carp, Carassius carassius by Acute Waterborne Nickel Exposure (수인성 니켈 급성 노출이 붕어, Carassius carassius의 반수치사농도, 혈액학적 성상 및 혈장 성분에 미치는 독성 영향)

  • Chang-Hoon, Joo;A-Hyun, Jo;Su-Min, Hong;Ji-Ho, Jeong;Yun-A, Ryu;Seock-Won, Jo;Jae-Hee, Song;Jun-Hwan, Kim
    • Journal of Marine Life Science
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    • v.7 no.2
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    • pp.102-112
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    • 2022
  • Crucian carp, Carassius carassius (Weight 39.7±3.1 g, Length 14.8±0.5 cm) were exposed to waterborne nickel at 0, 10, 20, 40, 80 and 160 mg Ni2+/l. The lethal concentration 50 (LC50) of C. carassius exposed to waterborne nickel was 117.69 mg Ni2+/l. In hematological parameters, RBC counts was significantly increased at 48 hours, whereas a significant decrease was observed at 96 hours. The MCV and MCH were significantly increased in the concentration of 80 mg Ni2+/l at 96 hours. The plasma components such as calcium, magnesium, glucose, cholesterol, total protein, AST, ALT and ALP were significantly changed by waterbonre nickel exposure. The results of this study suggest that the nickel exposure to C. carassius affects the survival rates, hematological parameters and plasma components as toxicity