• Title/Summary/Keyword: Sea states

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Optimized Ballast Water Exchange Management for Bulk Carrier (BULK 선용자동 Ballast Water Management Plan 개발)

  • HONG CHUNG YOU;PARK JE WOONG
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2004.05a
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    • pp.67-72
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    • 2004
  • Many port states such as New Zealand, the USA, Australia and Canada have strict regulations to prevent ships which arrive in their port from discharging polluted ballast water which contain harmful aquatic organism and pathogens. They are notified that transfer of polluted ballast water can cause serious injury to public health and damage to property and environment. For this reason, they perceived that the ballast exchange in deep sea is the most effective method, together with submitting the ballast management plan which contains the effective exchange method, ballast system and safety consideration. In this study, we pursued both nautical engineering analysis and optimization of algorithm in order to generate the sequence of stability and rapidity. Heuristic Algorithm was chosen on the basis of optimality and applicability to a sequential exchange problem. We have built an optimized algorithm, for automatic exchange of ballast water, by redefining core elements of the $A^\ast$ algorithm, such as node, operator and evaluation function. Final version of the optimized algorithm has been applied to existing bulk carrier and the performance of the algorithm has been verified successfully.

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On the Fracture of Polar Class Vessel Structures Subjected to Lateral Impact Loads (횡충격하중을 받는 빙해선박 구조물의 파단에 관한 연구)

  • Min, Dug-Ki;Cho, Sang-Rai
    • Journal of the Society of Naval Architects of Korea
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    • v.49 no.4
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    • pp.281-286
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    • 2012
  • Single frame structures with notches were fractured by applying drop impact loadings at room temperature and low temperature. Johnson-Cook shear failure model has been employed to simulate the fractured single frame structures. Through several numerical analyses, material constants for Johnson-Cook shear failure model have been found producing the cracks resulted from experiments. Fracture strain-stress triaxiality curves at both room temperature and low temperature are presented based on the extracted material constants. It is expected that the fracture strain-stress triaxiality curves can offer objective fracture criteria for the assessment of structural fractures of polar class vessel structures fabricated from DH36 steels. The fracture experiments of single frame structures revealed that the structure on low temperature condition fractures at much lower strain than that on room temperature condition despite the same stress states at both temperatures. In conclusion, the material properties on low temperature condition are essential to estimate the fracture characteristics of steel structures operated in the Northern Sea Route.

An Economic Analysis of Desalination for Potential Application in Korea (국내 적용을 위한 해수 담수화 경제성 분석)

  • Park, No Suk;Park, Hee Kyung;Park, Mi Hyun;Kim, Byung Duck
    • Journal of Korean Society of Water and Wastewater
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    • v.12 no.3
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    • pp.48-54
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    • 1998
  • Korea becomes one of the countries which suffer from water shortage. It is expected that its water shortage in the early 2000's will be more than 10% of the annual demand. The shortage problem is more serious in the coastal areas where many industry complex locate. To solve the shortage problem, seawater desalination gets more attention as an alternative water supply source since Korea is surrounded by sea on its three sides. For potential application of seawater desalination in Korea, an economic analysis was conducted using cost data for the plants in the Middle Ease areas, The United states and others. The study is to provide a basis for the government to establish a strategy for promoting seawater desalination in Korea. It is discussed that the Reverse Osmosis (RO) process gets cheaper over times than the thermal processes of Multi-stage Flash Distillation (MSF) and Multi Effect Distillation (ME), especially in case where the capacity is less than about 50,000 ton/day. The unit cost of RO seawater is analyzed about US$1.35/ton in 1990 price. Since the Desalination plant can be operated regardless of weather conditions, industries in Korea's coastal areas which suffer from frequent droughts and water shortages are recommended to look into this option with more attention.

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Genomic Regions associated with Necrotic Enteritis Resistance in Fayoumi and White Leghorn Chickens

  • Kim, Eui-Soo;Lillehoj, Hyun S.;Sohn, Sea Hwan;Hong, Yeong Ho
    • Korean Journal of Poultry Science
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    • v.42 no.1
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    • pp.27-32
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    • 2015
  • In this study, we used two breeds of chicken to identify genomic regions corresponding to necrotic enteritis (NE) resistance. We scanned the genomes of a resistant and susceptible line of Fayoumi and White Leghorn chickens (20 birds/line) using a chicken 60 K Illumina SNP panel. A total of 235 loci with divergently fixed alleles were identified across the genome in both breeds; particularly, several clusters of multiple loci with fixed alleles were found in five narrow regions. Moreover, consensus 15-SNP haplotypes that were shared by the resistant lines of both breeds were identified on chromosomes 3, 7 and 9. Genes responsible for NE resistance were identified in chicken lines selected for resistance and susceptibility. Annotation of the regions spanning clustered divergently fixed regions revealed a set of interesting candidate genes such as phosphoinositide-3-kinase, regulatory subunit 5, p101 (PIK3R5) and inositol 1,4,5-trisphosphate receptor 1 (ITPR1), which participate in immune response. Consensus haplotypes were found in regions containing possibly relevant genes, such as myostatin and myosin, which play important roles in muscle development. Thus, genome scans of divergent selection in multiple chicken lines and breeds can be used to identify genomic regions associated with NE resistance.

Experimental Study for Influence of Summertime Heat Sources and Basic States on Rossby Wave Propagation (여름철 열원과 기본장이 로스비 파동전파에 미치는 영향에 대한 실험 연구)

  • Kim, Seong-Yeol;Ha, Kyung-Ja;Yun, Kyung-Sook
    • Atmosphere
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    • v.20 no.4
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    • pp.505-518
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    • 2010
  • We investigated the impacts of the diabatic heating location, vertical profile and basic state on the Rossby wave propagation. To examine the dynamical process of individual responses on the regional heat source, a dry version of the linear baroclinic model was used with climatological summertime (JJA) mean basic state and vertical structure of the diabatic heating for 1979-2008. Two sets of diabatic heating were constructed of those positioned in the mid-latitudes (Tibetan Plateau, eastern Mediterranean Sea, and the west-central Asia) and the tropics (the southern India, Bay of Bengal, and western Pacific). It was found that using the principal component analysis, atmospheric response to diabatic heating reaches to the steady state in 19th days in time. The prescribed mid-latitude forcing forms equivalent barotropic Rossby wave propagation along the westerly Asia jets, whereas the tropical forcing generates the Rossby wave train extending from the tropics to mid-latitudes. In relation to the maximum vertical profile, the mid-level forcing reveals a stronger response than the lower-level forcing, which may be caused by more effective Rossby wave response by the upper-level divergent flow. Under the different sub-seasonal mean state, both of the tropical and mid-latitude forcing induce the different sub-seasonal response intensity, due to the different basic-state wind.

A Review on Monitoring the Everglades Wetlands in the Southern Florida Using Space-based Synthetic Aperture Radar (SAR) Observations

  • Hong, Sang-Hoon;Wdowinski, Shimon
    • Korean Journal of Remote Sensing
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    • v.33 no.4
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    • pp.377-390
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    • 2017
  • Space-based Synthetic Aperture Radar (SAR) observations have been widely and successfully applied to acquire invaluable temporal and spatial information on wetlands, which are unique environments and regarded as important ecosystems. One of the best studied wetland area is Everglades, which is located in southern Florida, USA. As a World Heritage Site, the Everglades is the largest natural and subtropical wilderness in the United States. The Everglades wetlands have been threatened by anthropogenic activities such as urban expansion and agricultural development, as well as by natural processes, as sea level changes due to climate change. In order to conserve this unique wetland environment, various restoration plans have been implemented. In this review paper, we summarize the main studies using space-based SAR observations for monitoring the Everglades. The paper is composed of the following two sections: (1) review of backscattered amplitude analysis and observations, and (2) review of interferometric SAR (InSAR) analysis and applications. This study also provides an overview of a wetland InSAR technique and space-based SAR sensors. The goal of this review paper is to provide a comprehensive summary of space-based SAR monitoring of wetlands, using the Everglades wetlands as a case study.

A Study on the Regime of Island and Dokdo on the UNCLOS (해양법상 섬제도와 독도)

  • Kwon, Moon-Sang
    • Ocean and Polar Research
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    • v.24 no.4
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    • pp.501-524
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    • 2002
  • Article 121 of the UNCLOS stipulates the regime of islands and grants different jurisdictions to islands and rocks. Especially, paragraph 3 gives different definitions and distinguishes the legal status of between islands and rocks. That is, rocks, which cannot sustain human habitation or economic life cannot have their own EEZ, continental shelf or the great-sphere maritime jurisdiction. In this paper various theories and state practicess on islands and rocks are examined with reference to Article 121 of UNCLOS. Also, the status of Dokdo as a rock or an island is examined in accordance with the interpretation of Article 121 of UNCLOS. National legislations, practices, and many scientific opinions are often contradictory and controversial with respect to the interpretation of Article 121 of the UNCLOS. However, it is believed that Article 121 of UNCLOS, particularly paragraph 3 has to be interpreted more strictly. That is because the highly developed modem scientific technology can be meaningless when the criteria of Article 121 of UNCLOS are to be inappropriately applied. Insular figures like ${\ulcorner}rocks{\lrcorner}$ could bring the inequitable effects disadvantageous toward the other party when the maritime delimitation is applied. Claiming and Intentionally extending maritime zone of a coastal states by assigning EEZ for small insular figures like ${\ulcorner}rocks{\lrcorner}$ is over-zealous nationalism which is illegal, and such practices must be recognized as actions bringing great harm to the neighboring nations and demise of the sprit of all mankind.

A String of Partners: China's Strategic Outreach in the Indian Ocean (인도양에서의 중국의 전략적 팽창)

  • Yu, Ji-Hoon
    • Strategy21
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    • s.38
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    • pp.321-347
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    • 2015
  • 중국은 지난 10년간 아시아에서의 영향력 확대를 위한 팽창정책의 일환으로 인도양 주변 국가들과의 관계발전을 위해 국가 차원의 노력을 기울여왔다. '진주목걸이 전략(String of Pearls Strategy')으로 묘사되는 중국의 인도양 정책의 개괄적 성격에 관한 연구는 여러 학자들에 의해서 시도되어 왔으나, 인도양 주변 개별국과들과의 협력과 개입의 정도(The variation in the extent of China's Engagement and Collaboration with States along Its Indian Ocean sea lines of communication)에 영향을 미치는 구조적 요인에 대한 연구는 부재해 왔다. 이 논문에서는 인도양 주변 국가들에 대한 개입 및 관계발전을 위한 중국의 인도양정책을 국제정치학의 이론 중 '방어적 신현실주의(Defensive Neorealism)'의 이론적 틀에 근거한 '연성적 힘의 균형(Soft Balancing)'의 관점에서 고찰해 보고, 중국의 인도양 정책은 이 지역에서 중국의 팽창에 대한 미국의 견제 및 반발(Backlash)을 억제하고 중국의 에너지 안보를 보장하기 위한 전략적 정책의 결과임을 조명해 본다. 더불어 중국의 인도양 진출에 따른 미국의 정책대안을 예측해 본다. 본 연구의 목적을 위해 이론적 틀에 기반한 가설을 설정하고 인도양 주변의 11개 국가에 대한 교차 사례연구(Cross-sectional Case Analysis)를 통해 타당성을 검증한다.

Analysis on the Present Business States of Coastal and Off-shore Fisheries by Type of Fishery (연근해어업의 업종별 경영현황 분석)

  • CHANG, Ho-Young
    • Journal of Fisheries and Marine Sciences Education
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    • v.15 no.2
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    • pp.166-175
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    • 2003
  • In order to offer fundamental data for the standard of comfilation of the budget on the compensation money for the reduction of fishing baot and index of investigation for computation on the average earnings of reduction of fishing boat, the fluctuation of actual outputs, expenses, earnings and the difference by type of coastal and off-shore fishery was investigated and analyzed. The results are as follows : 1. The average ouput money by large powered purse seine fishery was much with about 3,510 million won, but the average output money by off-shore gill nets fishery was little with about 8.4 million won. 2. The average catch by large powered purse seine fishery was many with about 296,000 M/T, but the average catch by eastern sea danish seine fishery was few with 4,600 M/T. 3. The average expense by large powered purse seine fishery was much with about 3,360 million won, but the average expense by diving fishery was little with 6.3 million won. 4. The average earning by large powered purse seine fishery was much with about 240million won, the average earning by offshore long line fishery was little with 18 million won. 5. The average earning rate by diving fishery was much with 31.62%, but the average earning rate by large powered purse seine fishery was little with 7.30%.

International Safety Management(ISM) Code and Duty of Due Diligence of Ocean Carrier (국제안전관리규약(國際安全管理規約)(ISM Code)과 해상운송인(海上運送人)의 주의의무(注意義務))

  • Yang, Jung-Ho
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.13
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    • pp.469-492
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    • 2000
  • "International Safety Management(ISM) Code" means the International Management Code for the Safe Operation of Ships and for Pollution Prevention as adopted by the Assembly, as may be amended by the International Maritime Organization. This Code have brought into force internationally since 1th July, 1998 by incorporated to the new Chapter Ⅸ in the SOLAS Convention. Accordingly those States which give effect to the SOLAS Convention will have to ensure that rules giving effect to the Code are introduced into their domestic legislation. The purpose of this Code is to provide an international standard for the safe management and operation of ships and for pollution prevention, by this to reduce the maritime casualty which could caused by neglect of person. To achieve this purpose the ISM Code specifies a number of broad 'safety management objectives' for owning or operation companies, and it requires that such companies should establish, implementing and maintain a written Safety Management System(SMS) covering a whole range of safety environmental and related matters. These requirements of the Code could effect on the carrier in some points such as duty of due diligence to care for cargo, due diligence to make the vessel seaworthy and burden of proof etc. In this respect, We should know that the ISM Code could effect on the carrier advantageously or disadvantageously subject to whether the carrier observed the requirement of the ISM Code. Although it does not add cause of liability or increase limitation of liability imposed to the carrier.

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