검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 24

        1.
        2023.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Fish school monitoring technology is utilized for various purposes, such as boat fishing and resource surveys. With advancements in information and communication technology, this technology has expanded its application to remote areas. Its significance has grown in fishing sites, particularly for improving the efficiency and cost-effectiveness of set-net fishing. Set-net fishing gears are not limited to coastal areas, but are also installed in inland and remote sea regions. Consequently, fishermen require technology that allows them to quickly transmit information about approaching fish schools and enables them to perform long-term monitoring. The development of remote monitoring technology for set-net fish schools must consider crucial design factors such as communication range, transmission speed, power consumption of information modules, and operational expenses. In this study, we developed a low-power remote monitoring module for set-net fish school based on WCDMA. The module was specifically designed to minimize power consumption, allowing for communication over long distances and extended operation times in set-net fishing applications. Furthermore, we developed a web server software application that enables remote access to fish schools and provides real-time weather information. The performance of the developed module was evaluated through set-net fishing site application and experiments with moving ships on the sea. The experimental results demonstrated that the remote monitoring system, consisting of the developed low-power remote monitoring module for set-net fish school based on WCDMA and a fish finder, had an average power consumption of 4.6 W, a maximum communication range of 22.84 km, and a data transmission and reception rate of 98.79%. The maximum fish school information transmission and reception rate was 97.26%.
        4,000원
        3.
        2021.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Interviews and boarding surveys were conducted in order to understand the actual usage of octopus pot in the coastal composite fishery in Jeollanam-do. According to the results of the interviews conduced by visiting the areas (Goheung, Yeosu and Wando), the number of octopus pots per nine-ton vessel were 30,000-80,000, and the number of daily usage pots were 7,000-10,000. The number of octopus pots per four-ton vessel was 40,000, and the number of daily usage pots were 4,000. As a result of the survey on two octopus pot fishing boats (9.77-ton and 4.99-ton) in Yeosu area, the daily catch weight of 9-ton class vessel was the minimum of 66.9 kg and the maximum of 159.6 kg. The daily catch weight of the four-ton class fishing vessel was from 31.3 kg to maximum 85.6 kg. The average number of octopus pot used per day in the nine-ton class vessel was 6,821 (the minimum of 6,031 and the maximum of 7,697) and 3,181 (the minimum of 2,282 and the maximum of 3,878) in the four-ton class vessel.
        4,000원
        7.
        2019.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        As a series of fundamental researches on the development of an automatic identification monitoring system for fishing gear. Firstly, the study on the installation method of automated identification buoy for the coastal improvement net fishing net with many loss problems on the west coast was carried out. Secondly, the study was conducted find out how to install an automatic identification buoy for coastal gill net which has the highest loss rate among the fisheries. GPS for fishing was used six times in the coastal waters around Seogwipo city in Jeju Island to determine the developmental status and underwater behavior to conduct a field survey. Next, a questionnaire was administered in parallel on the type of loss and the quantity and location of fishing gear to be developed and the water transmitter. In the field experiment, the data collection was possible from a minimum of 13 hours, ten minutes to a maximum of 20 hours and ten minutes using GPS, identifying the development status and underwater behavior of the coastal gillnet fishing gear. The result of the survey showed that the loss of coastal net fishing gear was in the following order: net (27.3%), full fishing gear (24.2%), buoys, and anchors (18.2%). The causes were active algae (50.0%), fish catches (33.3%) and natural disasters (12.5%). To solve this problem, the installation method is to attach one and two electronic buoys to top of each end of the fishing gear, and one underwater transmitter at both ends of the float line connected to the anchor. By identifying and managing abnormal conditions such as damage or loss of fishing gear due to external factors such as potent algae and cutting of fishing gear, loss of fishing gear can be reduced. If the lost fishing gear is found, it will be efficiently collected.
        4,000원
        11.
        2018.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, the conventional cylinder-shaped lower bar on the canvas was modified and its performance was tested to improve the opening force of the stow net on anchor. The improved new lower bar used in the test is consisted of 13 flat bars with a length of 1.8 m, a width of 0.075 m and a thickness of 4 mm, and a pipe with a length of 2.0 m and a diameter of 50 mm. A stow net with the improved lower bar and a stow net with an existing lower bar were installed underwater and their trajectories for 21 hours were examined. To confirm their trajectories, GPS loggers were attached to the buoys on the left and right canvases and the buoy of the hauling rope. As a result of the test, the rotation of the gear with the improved bar was smoother than that with the existing bar. As a result of comparing the changes in the interval of the buoys attached to the canvas after the low and high tide, the buoy spacing of the gear with the improved bar is wider than that of the conventional gear; moreover, the larger the interval, the smoother the rotation of the fishing gear was. Therefore, it is considered that using the improved lower bar can enhance the performance of the stow net.
        4,000원
        15.
        2017.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigated the drag coefficient and lift coefficient of thirteen kinds of knotless nettings used for large purse seine gear. By comparing the hydrodynamic characteristics with nets of the previous study, the characteristics of this study were derived as a purse seine gear. Thirteen kinds of nettings with different length of bar () and diameter () were used in the experiment, out of which six kinds used the 30 mm in mesh size and three kinds with 40 mm. The drag coefficient ( ) also increased with increasing . It can be expressed as        at a current speed 0.4 m/s and        at a current speed 0.5 m/s. Compared with previous studies, drag coefficient values were similar to knotless net of similar  and smaller than drag coefficient of knot net. Therefore, using knotless net in a purse seine has the advantage of reducing the resistance acting on the purse seine gear.
        4,300원
        19.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, a new designed propeller was applied on 24 ton class squid jigging vessel to reduce of fuel consumption. The selected squid jigging boat was under construction at the shipyard to determine the resistance of the hull through the model experiment. The propeller design was carried out by using the experimental data and ITTC procedures. Sea trials were performed by measuring the speed and the horsepower required by the condition of five power levels of engine load, namely 70%, 80%, 90%, MCR and maximum engine power. The speed and delivered horse power were compared between the conventional propeller and the new design propeller. Delivered horse power by installing the new propeller takes 90% engine load at start-up conducted by decreased 9.06%. The measuring speed is increased up to the 0.6 knots in the low-speed range to high range. This study showed that only the design and installation of a new propeller can improve the propulsion efficiency of the boats; furthermore, reduce fuel costs can be achieved at the same time by improving the increased cruising speed.
        4,000원
        20.
        2015.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        As a series of research plan, this study is to provide basic data necessary for the development of fishing industry which will contribute in establishing sound fishing culture in Jeju island through systematic management of fishing, protection of fishery resources and establishment of safety measures for fishermen in accordance with ‘Fishing Management and Support Act’. To attain the proposed objective, this study conducted literature review and surveys on restriction standards of harmful substances generated from fishing equipment and baits, examined the current status of fishing management in popular fishing sites of other cities, and then reviewed and analyzed the fishing management and fishing–restriction zones in Jeju island. The survey on the opinions on the restriction criteria of fishing methods, tools and period, including the acceptable standards for harmful substances showed that general fishermen preferred ‘alleviating the measure (44.8%)’ to ‘aggravating the measure (23.0%)’. Meanwhile, maritime police showed dominant opinion toward ‘aggravating the restriction (52.2%)’ over ‘alleviating the measure (4.3%)’. Furthermore, fishing–related enterprise is favored ‘aggravating the restriction (32.6%)’ over ‘alleviating the measure (27.9%)’. In the survey on the tolerance of fishing baits including criterion for content of certain substance in different types of bait, it showed 57.5% of general fishermen preferred alleviating restriction criteria while 20.7% of them favored tougher restriction. Whereas, 33.3% of maritime police group insisted such fishing baits should be more restricted while 16.7% answered it should be alleviated. 35.9% of fishing–related enterprise was in favor of alleviation while 14.3% preferred aggravation. Upon investigation on the status of fishing management in other cities and towns, it turned out that most of them had safety and convenience facilities, installed warning and guide signs in fishing sites, and set no fishing zones. The review of fishing management and restricted area showed that 10 sites required access restriction and 2 of 10 sites were considered to be partially restricted for weather and season. 82 fishing sites were regarded as unnecessary to be restricted and installation of safety facility and guide signs is necessary for the safety of fishermen.
        4,000원
        1 2