• Title/Summary/Keyword: Marine

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A Study on the Probability Analysis of Marine Casualty (해양사고의 확률적 분석)

  • Jang Woon-Jae;Lim Chul-woo;Keum Jong-Soo
    • Proceedings of KOSOMES biannual meeting
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    • 2004.05b
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    • pp.13-18
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    • 2004
  • The marine traffic congestion has increased due to the expansion of vessel traffic volume in Korean coastal waterway these days. Heavy traffic could bring serious marine casualties which cause the loss of human lives, properties and marine pollution in coastal area. In this paper. the probability analysis of marine casualties in Korean coastal To achieve this aim, clears up the cause of accident and examines closely the mutual relations among marine casualties, weather condition, and marine traffic volume. These casualties are classified into several pattens or the point of view of ship‘s size, ship’s type and ship‘s age and its characteristics of each patten are described in detail.

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A Study on the Improvement of Marine Traffic System in the Ulsan Approaching Waters (울산항 접근 수역의 해상교통시스템 개선에 관한 연구)

  • Lee, Seung-Hwan;Kim, Chol-Seong;Jong, Jae-Yong;Park, Gyei-Kark
    • Proceedings of KOSOMES biannual meeting
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    • 2006.11a
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    • pp.25-30
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    • 2006
  • Marine traffics near Ulsan approaching waters are crossing and converged at the diverging point of No.1 route- No.2 route and No.1 route -No.3 route and are also concentrated at near No1. route approaching area and the headland of cape Gawnjeol. Because the number of berth will increase to 78 from 49 until 2011 due to additional developments, minor modification is expected for the water utilities. This study examined environmental conditions, marine accidental data, marine traffic capacity, traffic flow survery and fisheries zone status near Ulsan approaching water area. Finally, a questionaire survey was carried ou for experts and users to propose new plan.

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A Model reference adaptive speed control of marine diesel engine by fusion of PID controller and fuzzy controller

  • Yoo, Heui-Han
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.7
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    • pp.791-799
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    • 2006
  • The aim of this paper is to design an adaptive speed control system of a marine diesel engine by fusion of hard computing based proportional integral derivative (PID) control and soft computing based fuzzy control methods. The model of a marine diesel engine is considered as a typical non oscillatory second order system. When its model and the actual marine diesel engine ate not matched, it is hard to control the speed of the marine diesel engine. Therefore, this paper proposes two methods in order to obtain the speed control characteristics of a marine diesel engine. One is an efficient method to determine the PID control parameters of the nominal model of a marine diesel engine. Second is a reference adaptive speed control method that uses a fuzzy controller and derivative operator for tracking the nominal model of the marine diesel engine. It was found that the proposed PID parameters adjustment method is better than the Ziegler & Nichols' method, and that a model reference adaptive control is superior to using only PID controller. The improved control method proposed here, could be applied to other systems when a model of a system does not match the actual system.

Investigation on electrochemical performance of Al anode material for marine growth prevention system

  • Kim, Seong-Jong;Jang, Seok-Ki;Han, Min-Su;Lee, Seung-Jun
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.8
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    • pp.968-973
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    • 2014
  • Aluminum anode of marine growth prevention system for ship is installed in seachest or sea water strainer. The Al anode is connected to a control panel that feeds a current to the anode. The dissolved ions produced by the anode are transferred in sea water, spreads through the sea water pipe system and creates a protective film in the pipelines. Thereby, corrosion in pipeline system significantly is reduced. In application on condition as a steel ship, the big accident can be caused by the corrosion. Accordingly, in this research, we evaluated influence of applied current and flow velocity on electrochemical characteristics of Al anode for marine growth prevention system (MGPS). Based on the results of the erosion-cavitation experiments, cavitation rate increased greatly until 120 min. of the experimental time and decreased a little at the point of 180 min. where pit grew and merging occurred but showed a tendency of steadily increasing consumption rates. Based on the results of the Tafel analysis, compared to static states, corrosion current densities show a rapidly increasing tendency when flow occurred.

The Primary Factors of Marine Casualties and the Counterplan for Promotion of Marine Safety (해난(海難)의 요인(要因)과 해상안전대책(海上安全對策))

  • Park, Byeong-Soo;Kang, Il-Kweon
    • Journal of Fisheries and Marine Sciences Education
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    • v.7 no.2
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    • pp.173-181
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    • 1995
  • In this paper, marine casualties occurred in Korean coastal and near-coastal seas, from 1989 to 1993, were analysed. The main results obtained were as follows : 1. According to the numerical component ratio of marine casualties, fishing vessels account for higher portion than other vessels and passenger vessels lower portion. On the other hand, in view of the occurring ratio of that, fishing vessels account for very low rate of accidents and passenger vessels very high rate. 2. Most of marine casualties resulted from the human factors such as careless operation and insufficient engine maintenance, etc. Collision accidents took a majority of all marine accidents in all of vessels, but engine trouble accounted for main cause of accidents in fishing vessels. 3. In view of the results on classifying marine casualties into time zone, great number of accidents took place in dawn, but that of fishing vessels in forenoon. 4. According to the view of the occurring ratio of the injury, the rate was 0.33% in total vessels and 0.18% in fishing vessels. 5. In view of the marine casualties by age and shipboard career, crews with 10~20 years shipboard career raised more marine accidents than others.

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The Effects of Catches of Marine Fish in China on Marine Fisheries in Korea (중국의 해면어류 생산이 우리나라 어업에 미치는 영향)

  • 박영명
    • The Journal of Fisheries Business Administration
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    • v.27 no.2
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    • pp.27-49
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    • 1996
  • The purpose of this paper is to find out how catches of certain species of marine fish in China influence the marine fisheries of Korea. The results are as follows: 1) While the catches of the main species of marine fish are over 74% in Korea, those of China are under 45%. 2) The main species of marine fish in China(MFC) are hair tails, jack mackerels, anchovies, mackerels, Spanish mackerels, pomfrets, redlip croakers, fie fish, sea breams, sardines, croakers and bigeyed herrings. 3) All the MFC belong to the main species of marine fish in Korea. 4) The fishing grounds of hair tails, jack mackerels, mackerels, Spanish mackerels, pomfrets and croakers in China are similar to those of Korea. 5) Catches of hair tails, jack mackerels, Spanish mackerels, pomfrets, file fish, sea breams and bigeyed herrings in China are many times more than those in Korea. Therefore Korea can't compete with China with such species of marine fish. 6) The price of MFC apart from mackerels and sardines is more competitive than the price of such species in Korea. When the catches of China's marine fish are imported, the species of China's marine fish that will have a great influence on the marine fisheries of Korea are hair tails, jack mackerels, pomfrets and sea breams.

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DNA Barcoding of the Marine Proteced Species Pseudohelice subquadrata (Decapoda, Varunidae, Pseudohelice) from the Korean Waters

  • Kim, Ji Min;Kim, Jong-Gwan;Kim, So Yeon;Choi, Woo Yong;Kim, Hyung Seop;Kim, Min-Seop
    • Animal Systematics, Evolution and Diversity
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    • v.36 no.3
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    • pp.228-231
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    • 2020
  • Pseudohelice subquadrata (Dana, 1851) is endangered due to its restricted habitat; hence, it has been designated as a marine protected species and endangered species by law in Korea. It has been recorded only Jeju-do and Geomun-do, Republic of Korea. The present study, is the first report on a cytochrome c oxidase subunit I DNA barcode for P. subquadrata. The maximum intra-specific genetic distance among all P. subquadrata individuals was found to be 0.5%, whereas inter-genetic distance within the same genus was 17.2-21.5% compared with Helice tientsinensis (Rathbun, 1931), H. tridens (De Haan, 1835), H. epicure (Ng et al., 2018), and Helicana wuana (Rathbun, 1931). Our barcoding data can thus be used as reference for restoration and conservation studies on P. subquadrata, which are designated as marine protected species.

Characterization of Chitinolytic and Antifungal Activities in Marine-Derived Trichoderma bissettii Strains

  • Dawoon Chung;Yong Min Kwon;Ji Yeon Lim;Seung Sub Bae;Grace Choi;Dae-Sung Lee
    • Mycobiology
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    • v.50 no.4
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    • pp.244-253
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    • 2022
  • Trichoderma fungi have been intensively studied for mycoparasitism, and the latter is closely related to their cell-wall degrading enzymes including chitinase. Here, we studied marine-derived Trichoderma spp., isolated from distinct sources and locations, for chitinolytic and antifungal activity. Based on morphological and phylogenetic analyses, two strains designated GJ-Sp1 and TOP-Co8 (isolated from a marine sponge and a marine alga, respectively) were identified as Trichoderma bissettii. This species has recently been identified as a closely related species to Trichoderma longibrachiatum. The extracellular crude enzymes of GJ-Sp1 and TOP-Co8 showed activities of chitobiosidase and b-N-acetylglucosaminidase (exochitinase) and chitotriosidase (endochitinase). The optimum chitinolytic activity of the crude enzymes was observed at 50 ℃, pH 5.0, 0-0.5% NaCl concentrations, and the activities were stable at temperatures ranging from 10 to 40 ℃ for 2 h. Moreover, the crude enzymes showed inhibitory activity against hyphal growth of two filamentous fungi Aspergillus flavus and Aspergillus niger. To the best of our knowledge, this is the first report of the chitinolytic and antifungal activity of T. bissettii.

Marine Disasters Prediction System Model Using Marine Environment Monitoring (해양환경 모니터링을 이용한 해양재해 예측 시스템 모델)

  • Park, Sun;Lee, Seong Ro
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.3
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    • pp.263-270
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    • 2013
  • Recently, the prediction and analysis technology of marine environment are actively being studied since the ocean resources in the world is taken notice. The prediction of marine disaster by automatic collecting marine environment data and analyzing the collected data can contribute to minimized the damages with respect to marine pollution of oil spill and fisheries damage by red tide blooms and marine environment upsets. However the studies of the marine environment monitoring and analysis system are limited in South Korea. In this paper, we study the marine disasters prediction system model to analyze collection marine information of out sea and near sea. This paper proposes the models for the marine disasters prediction system as communication system model, a marine environment data monitoring system model, prediction and analyzing system model, and situations propagation system model. The red tide prediction model and summarizing and analyzing model is proposed for prediction and analyzing system model.

The Development Object by the Establishment of New Index of Marine and Fisheries Education in 21st Century (21 세기 수·해양교육의 새로운 지표(指標) 설정에 의한 발전방향)

  • Lee, Kil-Rae
    • Journal of Fisheries and Marine Sciences Education
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    • v.12 no.2
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    • pp.123-141
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    • 2000
  • Facing to millenium, The new development of maritime and Fisheries education schemes will be cultivated in order to challenge global maritime nations as the new target of marine education which was established new index and problems of maritime education in place. First, The index of Marine and Fisheries education of 21st century was aimed at the spirits of expansion of territories of the era of ambassador of Jang Bo Go Sylla dynasty where marine trade had been prevailed between sylla and china leading to the spirits of marine pioneer in the northeastern Asian regions. and we must maintain the great desire and frontier spirities toward the marine industry also, adjust to the development and frontier spirits. Secondly, In order to cultivate the prominent man power for the marine industry, the government shall be specialized for the agency of marine education system, expand the educational installation, reforms the content of curriculum, to be adjust the global education system, also, enlarge the scholarship for the student, exemption tuition fees, installed the dormitory for the student, professors and teachers engaging in this parts have to lead the students with the pride and confidence and must provided the chance of job after he had completed for their on boarding life. Thirdly, for the secure responsible officer, the authorities has a schedules for enlarging the chance of studying and training also have to accumulate the practical experience and should enforce the retraining to the prof's and teachers also improve the leaders quality, on the other hand. The position of prof's and teachers will be elevated with the gaining of education philosophy and special treatment by the authorities. Fourth, to receive the positively marine industry educational system. First of all, have to provide the cooperation of industries and academy and they satisfy their job and change the their way of thinking and should notify the importance of government strategical industry by the mass-media system. Against the new marine era, we must participate the marine industry positively, have to elevate the culture of mankind and also, have provide the basement of prominent man-power for the marine industry in future.

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