• Title/Summary/Keyword: Fishing operation

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Study of Practical Cathodic Protection of 2nd Class Stainless Steel Shaft by means of Al Sacrificial Anode (AL계 희생양극에 의한 2종스테인리스 강축의 음극방식 실용화 연구)

  • Son, Yeong-Tae;Lee, Myeong-Hun;Lee, Hui-Jun
    • Journal of Korea Ship Safrty Technology Authority
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    • s.22
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    • pp.34-53
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    • 2007
  • In the case of hull material. large sized merchant ships are made of steel, on the other hand FRP or wood are used for small sized fishing boats. At present in Korea approximately 88,500 fishing boats are in operation of which 70% are made of FRP In the meantime, stainless steel is frequently used as shaft materials of the small-size FRP fishing boat. Namely, the kinds of shaft materials are STS 304(18Cr-8Ni), STS 316(18Cr-12Ni-2.5Mo steel) and STS 630(17Cr-Ni-Nb steel)etc. Among these things, STS 304 which is the cheapest and having ordinary corrosion resistance is most widely used as 2nd class shaft material. But, using STS 304 for shaft system material of the small-size FRP fishing boat on seawater environments entails a severe corrosion which causes shaft system troubles. Particularly, the corrosions tend to be concentrated of the stern and bow side, propeller shaft surface of inside of stern tube and the boat having no stern cooling pipe line system. As a solution for those problems, research on the ways to mitigate corrosion on the part of 2nd class stainless steel shaft have been undertaken. In the result, not only clarification for the reason of corrosion of the part of stainless steel shaft used mainly for the small-size FRP fishing boat was done, but also most optimal corrosion protection system was developed by experimenting shaft's protection simulation based of the electrochemical cathodic protection principle. In addition, verification through the field test on the optimal cathodic corrosion protection method by means of aluminum sacrificial anode was carried out. In this study, effective and economical shaft's protection system is suggested to the small-size FRP fishing boat operator by substantiating the results obtained from the research on the optimal cathodic protection.

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Motion Response Estimation of Fishing Boats Using Deep Neural Networks (심층신경망을 이용한 어선의 운동응답 추정)

  • TaeWon Park;Dong-Woo Park;JangHoon Seo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.7
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    • pp.958-963
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    • 2023
  • Lately, there has been increasing research on the prediction of motion performance using artificial intelligence for the safe design and operation of ships. However, compared to conventional ships, research on small fishing boats is insufficient. In this paper, we propose a model that estimates the motion response essential for calculating the motion performance of small fishing boats using a deep neural network. Hydrodynamic analysis was conducted on 15 small fishing boats, and a database was established. Environmental conditions and main particulars were applied as input data, and the response amplitude operators were utilized as the output data. The motion response predicted by the trained deep neural network model showed similar trends to the hydrodynamic analysis results. The results showed that the high-frequency motion responses were predicted well with a low error. Based on this study, we plan to extend existing research by incorporating the hull shape characteristics of fishing boats into a deep neural network model.

A study on the resistance affecting on the engine power in towing fishing gear of a bottom trawl ship (저층 트롤선의 예망 시 기관출력에 영향을 미치는 저항들에 관한 고찰)

  • Woo-Gyeong WANG
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.4
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    • pp.344-353
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    • 2023
  • In the actual sea, the additional resistance due to external force such as wind, current and wave is accompanied, and the required power is added in response to these resistance. Especially when the ship is sailing at low speed, the effects of wind and current have a great impact on the safe control of the ship. Likewise, it is thought that the effects of wind and current have a great impact on the trawl ship control since the towing speed of a bottom trawl ship is a low speed of 3 to 4 knots. If the reduce of ship speed and the increase of engine power due to the influence of wind and current can be identified, the safe towing power can be calculated based on a given engine output. Thus, the appropriate size of a fishing gear can be determined. In this study, a total of 20 trawl operations were conducted for seasonal maritime research in the same research area according to the operation mode of propeller. Based on navigation data, trawl fishing data, and engine performance data acquired during the towing fishing gear, and data of ship speed, hull resistance, fishing gear resistance, wind force and current force according to an incidence angle were estimated. The overall power for these loads was calculated and compared with the measured engine power, and the effects of wind force and current force on the engine power were investigated.

LAN Based MFD Interface for Integrated Operation of Radio Facilities using Fishery Vessel (어선용 무선설비의 통합운용을 위한 LAN 기반 MFD 인터페이스)

  • In-ung Ju;In-suk Kang;Jeong-yeon Kim;Seong-Real Lee;Jo-cheon Choi
    • Journal of Advanced Navigation Technology
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    • v.26 no.6
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    • pp.496-503
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    • 2022
  • In the reality that the fishing population is decreasing and the single-man fishing vessels is increasing, mandatory equipment for navigation and radio equipments for the safety of fishing boats has continued to be added. Therefore, many equipment such as navigation, communication and fishing are installed in the narrow steering room, so it is very confusing and a number of monitors are placed in the front, which is a factor that degrades the function of maritime observation. To solve this problem, we studied an interface that integrates and operates to major radio facilities such as very high frequency-digital selective calling equipment (VHF-DSC), automatic identification system (AIS) and fishing boat location transmission device (V-pass) into one multi function display (MFD) based on LAN. In addition, IEC61162-450 UDP packets and IEC61162 sentence were applied to exchange data through link between MFD and radio equipments, and additional messages needed for each equipment and function were defined. The integrated MFD monitor is easily operated by the menu method, and the performance of the interface was evaluated by checking the distress and emergency communication functions related to maritime safety and the message transmission status by equipment.

A Study on the Safety Management Standards and Safety Indicators Private Lodging in Farming and Fishing Villages in Rural Area (농어촌민박의 안전관리 기준 및 안전지표에 관한 연구)

  • Suh, hey-sung;Lee, Yong-soo;Kim, Youna-ah
    • Journal of the Korea Institute of Construction Safety
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    • v.3 no.1
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    • pp.1-8
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    • 2020
  • Various support is provided for the increase in the number of private lodging users in farming and fishing villages and related government policies. However, the bed-and-breakfast accommodation in rural areas lack safety standards or safety indicators for the service pension Gangneung, carbon monoxide leak accident in December 2018, 2020 East Sea in January, Pension. Large gas explosion, accident and is threatening the security of their citizens. Unlike lodging facilities, private lodging in farming and fishing villages is allowed to operate with certain requirements such as fire extinguishers and fire alarms. The purpose of this study is to present safety standards and safety indicators for lodging facilities in farming and fishing villages, which are necessary for the operation management and inspection of local governments and the government related to lodging in farming and fishing villages. Through the study, safety management areas of private lodging in farming and fishing villages were divided into facility safety, fire safety, food safety and living safety, and detailed inspection indicators were presented. There is an academic implication that research on safety management of lodging facilities has been expanded through safety research in areas related to private lodging in farming and fishing villages. It has practical implications in that it provides management standards and indicators that can be used for safety management of private lodging in farming and fishing villages. The limitations of this study are that more studies on private lodging in farming and fishing villages are expected to be conducted through the results of this study, and the lack of research on accommodation safety has prevented more detailed indicators from being derived.

A Political-Economic Study on Cooperative Squid Fishing East to the $E128^{\circ}$ (동경 128도 이동 오징어 공조조업에 관한 정치경제학적 연구)

  • Park Seong-Kwae
    • The Journal of Fisheries Business Administration
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    • v.35 no.2
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    • pp.91-115
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    • 2004
  • The main purpose of this study is to analyze the cooperative squid fisheries problems surrounding the $E128^{\circ}$, established by the 1965 Korea - Japan Fisheries Agreement which banned Korean large trawlers' fishing east to the $E128^{\circ}$ In fact, the moratorium was put on by Japans request. However, such issue did not occur until the filefish stock in the southern Korean sea, which was a major target fish species of the large trawl fisheries, The filefish stock collapsed completely around 1991 and at the same time most of bottom fish stocks in the East China Sea began to show a symptom of over - exploitation. Thus, the off - shore large trawlers learned to have a little opportunity of finding out alternative fish stocks as well as fishing grounds. Fortunately, at that time squid resource stock and consumption were on the increasing trend. The large trawl fisheries were able to economically exploit squid stock east to the $E128^{\circ}$ through cooperative fishing with squid angling light boats in the East and East - South Sea, even though such cooperative fishing activities violate the existing fishery laws apparently. Some important reasons that the large trawlers have continued the cooperative fishing seem to be because (ⅰ) squid resource stock has been on the increasing state over time, (ⅱ) the trawl fisheries have made a significant contribution to meeting domestic and export demands and stabilizing squid prices, and (ⅲ) they have kept domestic squid market from foreign competition. However, the new Korea - Japan fisheries agreement in 1998 provided a momentum of questioning the effectiveness of the $E128^{\circ}$ by the squid - related fisheries other than the squid angling. Serious conflicts between squid - related fisheries began to emerge and to be much intensified. Squid angling industries in the East opposed to large trawlers's efforts to formalize such illegal cooperative squid fishing activities. Their main argument was that such formalizing would definitely make the East coast squid prices lower and in turn their business performance would be worse off. The results of quantitative analysis suggest that the trawlers' massive landing may have a significant influence on lowering the east coast squid prices. Now, an important issue that the squid - related fisheries and the government are facing is to solve such complex squid fishing problems through a multi - participatory negotiation process, including price stabilization, total allowable catch level and its operation schemes, $E128^{\circ}$ rearrangement, and so on.

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South Korea and Japan's fishing Villages law and Sea Port law Analysis and the Development Direction of Fisherina (한국과 일본의 어촌·어항법 분석과 피셔리나 개발방향)

  • Yang, Young-Cheol;Lee, Jae-Hyung
    • Journal of Navigation and Port Research
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    • v.36 no.1
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    • pp.81-87
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    • 2012
  • This study is enabled our country to compare and analyze Korea's and Japan's marina development related fishing villages in the sea ports, sea port law's systematical research, approved permissions, and operation related ordinance enactments. Henceforth, the results of the research regarding the fisherina development model appropriate for domestic circumstances are as follows. First, the fisherina must be developed in a way to create a new source of income in the fishing villages. The initial steps must be taken in improving the fishing industry and revitalizing the marine leisure sports. Second, there must be a development of a system to reduce its development costs. Third, the existing sea port's unused equipments must be developed in a remodeled form.

Design of Web application for Deep-sea fishing Sailing Information based by RIA (원양어선 항해정보를 위한 RIA기반의 웹 어플리케이션 설계 및 구현)

  • Jung, Hoe-Jun;Park, Dea-Woo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.10
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    • pp.2272-2278
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    • 2011
  • The company which have deep-sea fishing vessel have to improve their voyage dashboard that was operating by manually to grasp sailing information of fishing vessel. This thesis design sailing information that is ship location on the globe, a catch of fish, and line of longitude and latitude to display on the map more visually by using on-line PC or DID (Digital Information Display). Thesis considered about designing web application which is available to visualize sailing information of 37 deep-sea fishing vessels in operation by using Flash-based RIA technology. This system was improving operator's and administrator's satisfaction of using information because, It make possible not only to grasp status of many vessels in one display but also to monitoring situation and deciding process.

Risk evaluation of fisher's safety on stow net fishing vessel (안강망어선에서 조업하는 선원의 위험도 평가)

  • HYUN, Yun-Ki;KIM, Hyung-seok;LEE, Yoo-Won
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.56 no.2
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    • pp.138-146
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    • 2020
  • Stow net fishery is one of the fishery with high fishing work accidents in southwestern sea of Korea. We conducted to serve as basic data for improving the healthy and safe working environment of fisher using risk assessment process (ISO45001) with fishermen's occupational accidents of the National Federation of Fisheries Cooperative (NFFC) from 2016 to 2018. The average occurrence rate of victim in this fishery was 9.04%, 16.7 times more than such rate in all industries. In addition, the average fatality rate was found to have a very serious level management to 31.06‱, 27.7 times more than such rate in all industries. The safety hazards of stow net fishery was more likely to occur by other general industrial groups, with more severe consequences after the accident. According to 4M analysis, 58.6% of all accidents were caused by human factors, 24.0% by environmental factors, 16.0% by mechanical factors, and 1.5% by managerial factors, respectively. The occurrence frequency by accident type was the highest in 187 cases (32.2%) for struck by object, 158 cases (27.2%) for slipping, and 94 cases (16.2%) for being in contact with machinery. Severity is the highest for others such as diseases etc., in the order of being struck by object, being in contact with machinery, falling from above slipping, collapsing, bumping, and burning. Being struck by object, being in contact with machinery, and slipping are high-risk groups, falling from above others, bumping, and burning are medium-risk groups based on the risk assessment using the occurrence frequency and severity of accident. The obtained results are expected to contribute to the safe operation environment subsidy for fishing crews on the stow net fishing vessel.

Underwater Visualization for Fish Behaviour Model in the Towed Fisheries using Chaos Theory (혼돈이론을 응용한 예망어구에 대한 어류반응 행동모델의 수중현상 시각화)

  • 박명철;김용해;하석운
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.3
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    • pp.645-653
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    • 2004
  • The prediction and its visualization on fish behaviour in relation to fishing gear are carried out based on field detection and observation during fishing operation. However, field observation is very difficult due to variable underwater environments and accordingly due to complex, chaotic response of fish behaviour in the physiological and ecological points. Therefore simple graphic display in previous results was not enough to represent real underwater images of the fishing gear and fish behaviour. In this study more actual visualization technique was developed using by previous fish behaviour model with chaos theory in order to predict, evaluate or analyse complex and non-linear phenomena of response patterns in complex fish behaviour. In addition, display of the fish finder was also designed to simulate the underwater fish detection and distribution in fishing ground. This suggested visualization tool was very similar to the information of the fish movement in the field observation in visual underwater reality and useful to check up between simulations and observations.