• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.4
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• pp.374-383
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• 2020

At ship design stage, the maneuverability is generally estimated based on the empirical formula or the computational fluid dynamic (CFD), which is one of the numerical simulation methods. Using the hydrodynamic derivatives derived through these methods can quantitatively estimate the maneuverability of target vessels and evaluate indirect maneuverability. Nevertheless, research on estimating maneuverability is insufficient for ships not subject to IMO maneuverability standard, especially fishing vessels, and even at the design stage, the empirical formula developed for merchant ships is applied without modification. An estimation error may occur due to the empirical formula derived from the regression analysis results of a model test if the empirical formula developed for merchant ships with different hull shapes is applied to fishing vessels without any modification. In this study, the modified empirical formula that can more accurately estimate the fishing vessel's maneuverability was derived by including the hull shape parameter of target fishing trawlers in the regression analysis process that derives Kijima et al. (1990) formula. As a result, the modified empirical formula showed an average estimation error of 6%, and the result improved the average error of 49% of Kijima et al. (1990) formula developed for merchant ships.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.7
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• pp.863-870
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• 2023

Ship capsize accidents are common in coastal waters, particularly involving small fishing boats. To prevent there overturing accidents in small fishing boats, their stabilities must be assessed at the initial design step. However, the available information during the initial design step is limited, posing challenges in performing a reliable stability evaluation. Therefore, this study presents a plan to estimate the transverse metacenter (GM) of small fishing boats using parameters such as KM, KG, and TRIM that can be determined at the initial design step. Stability was evaluated by comparing GM with the minimum transverse metacenter (GMmin) specified in the standard safety evaluation criteria for fishing boats. To calculate the required trim value for hydrostatic characteristics using K-SHIP, a stability assessment program provided by the Korea Maritime Safety and Transportation Corporation, the initial trim state is estimated based on the ship lines using the commercial CFD program STAR-CCM+. GM is then calculated by assessing the hydrostatic characteristics in relation to the boat lines using K-SHIP. Furthermore, the stability of the fully loaded state is compared by subtrcating GM from GMmin. One constructed ship is designated as the standard ship, and the stability assessment method proposed in this study is applied to evaluate stability and validate its effectiveness. Consequently, the representative line of a 4.99-ton fishing boat and nine modular lines models derived from it were evaluated, ultimately identifying a relatively superior stability.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.1
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• pp.26-33
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• 2003

The SSB(Single Side Band) communication in the 27MHz band has mainly been using between fishiery station and small fishing ship less than 101ons, but the most of small fishing ship are depend on cellular system. When accident for small ship at sea happens, It's very important to communicate continuously for preventing the collision and taking action. At present it is hard to control small fishing ship and provide information properly by using 27MHz SSB channel. Therefore in this paper We present TRS communication system applied for small fishing ship to protect the safety and life at sea and to prepare for emmergency, and also validate it's application.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.196-201
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• 2002

The SSB(Single Side Band) communication in the 27MHz band has mainly been using between fishiery station and small fishing ship less than 10tons, but the most of small fishing ship are depend on cellular system. When accident for small ship at sea happens, It's very important to communicate continuously for preventing the collision and taking action. At present it is hard to control small fishing ship and provide information properly by using 27MHz SSB channel. Therefore in this paper We present TRS communication system applied for small fishing ship to protect the safy and life at sea and to prepare for emmergency, and also validate it's application.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.3
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• pp.321-332
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• 2015

In an attempt to find the improvement of the fishing efficiency according to the hull form remodeling for the 3 tuna purse seiner, the Catch-Per-Unit-Effort (CPUE) for that undertaken before (2008) and after (2010) was analyzed. In addition, the CPUE of 6 similar ships operated same period and same fishing ground. As result, it came to verify that the three modified ships had a significant value on the CPUE. An another index for the improvement of fishing efficiency is the rate of reduction of fuel oil consumption for the modified ships. Fuel oil consumption per day in service speed as comparing with the original ships were reduced 2.1%, 4.0% and 5.1% on the modified ship A, B, and C respectively. And each ship's service speed was increased 1.0 kt, 0.6 kt, and 0.4 kt according to the modified ship A, B, and C in due order. In the conclusion, the remodeling job with newly equipped bulbous bow, lengthened slipway and enlarged rudder area were improved fairly much on fuel oil efficiency, the ship's speed, and in the end, that led to the improving fishing efficiency. Hence, the remodeling of tuna purse seiner come to improve not only the fishing performance, but contribute to the reduction of operating cost by saving energy for the fisheries industry.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.4
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• pp.302-315
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• 2021

In this study, factors such as improvement of a fishing process and safety, reduction of the labor force and headcount and development of the automation technology for offshore (eel and crab) pot fishing vessels were analyzed. A questionnaire survey was conducted to analyze and select the key factors using independent/paired sample t-test and correlation analysis, and a living lab was operated with ship owners, skippers and experts to discuss practical needs of the site. From the result of questionnaire survey and field requirements, it was possible to understand the level of awareness of ship safety, general safety equipment, fishing work process and fishing safety equipment from the point of view of the field. In addition, there were differences in the measurement results of each items because the working environment and experience were different according to the position of the ship owner and the skipper. The results of the questionnaire survey and various perceptions of field stakeholders were reflected when analyzing the fishing system and fishing process to choose the development equipment applicable to the field. From the analysis results, the selected development equipment based on the fishing equipment and process currently in operation are pot washing device, catch separation and fish hold injection device, length limit regulations and bait ejection device after use, automatic main line winding device, bait crusher, automatic (crab) pot hauling separator and so on.

• Journal of Ship and Ocean Technology
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• v.8 no.3
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• pp.1-7
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• 2004

The current paper deals with the safety of fishing vessels, which needs more speculations than other ship types. The characteristics of accidents of fishing vessels are rather different compared with other commercial vessels. In the context, the methodology of the formal safety assessment, one of the important issues in the maritime world to enhance the safety of marine vehicles, are reviewed and consulted along with other methodologies to see its applicability for fishing vessels. It is anticipated that further effective measures for better safety of fishing vessels can be identified including due considerations of the aspect of human elements, i.e. cultural environment.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.5
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• pp.677-683
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• 2008

The electric propulsion system us closely related with the economical efficiency of ship operation. Fuel efficiency is mainly decided by propulsion system such as diesel engine, propulsion motor and steam turbine. The hybrid propulsion system for fishing boat consists of diesel engine and battery as propulsion power source. This paper is to design battery capacity according to power consumption with ship operation condition, and to test the power consumption of model ship in the circulating water channel. As a result. it can be known that the optimum ship operation condition affects the fuel efficiency.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.1
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• pp.57-68
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• 2021

In order to collect basic data for the improvement of fishing systems in coastal improved stow net fishery, a questionnaire survey and on-site hearing were conducted from May 10 to June 11, 2019 on the basic items of coastal improved stow net fishery and safety accidents that occurred during fishing operation. The questionnaire for the survey on the actual conditions of coastal improved stow net fishery consisted of a survey on basic matters (six questions) and a questionnaire (six questions) on safety accidents occurring during fishing operation. The results of the survey on basic items were analyzed by region (Incheon, Seocheon, Gunsan and Mokpo), by the captain's age (less than 50 years of age, 50 to 60 years and more than 60 years of age), by the captain's career (less than 20 years, 20 to 30 years, 30 to 40 years and more than 40 years) and by the age of fishing vessel (less than 10 years, 10 to 20 years and more than 20 years). According to the survey on basic items of coastal improved stow net fishery such as the captain's age, the captain's career, the age of fishing vessel, the fishing nets in use, the crews on board and the operation days per voyage by region, the average captain's age was 55.7 years, the average captain's career was 20.5 years, the average age of fishing vessels was 9.0 years, the average numbers of nets used by fishing boats was 14.0 sets, the average numbers of crew on board a fishing boat was 4.4 persons and the average numbers of operation days per voyage was 4.9 days (p < 0.05). As a result of the survey on safety factors during fishing operations, such as experience of ship accidents, major causes of ship accidents experienced, causes of ship accidents (first priority), experience of human accidents, major causes of human accidents, and causes of human accidents (first priority), more than 96% of the respondents experienced ship accidents including collisions with other vessels or fishing gear during fishing operations. The most significant cause of the accident was the other's fishing gear installed in the fishing grounds. The first possible causes of ship accidents during fishing operations were found to be other fishing gear installed in fishing grounds, steering or engine failure, and inability to avoid accidents during casting and hauling nets. The survey of the experience of human accidents, such as injuries or sea falls, showed that more than 90% of the respondents experienced human accidents during fishing operations. The most important cause of accidents experienced during fishing operations was stucked in a fishing gear during casting and hauling nets. The first important causes of accidents during fishing operations were movement of the fishing gear during casting and hauling nets, damage of the fishing gear such as rope cutting. The results are expected to be provided as a basic data to prevent safety accidents occurring during fishing operation and improve the fishing system in the coastal improved stow net fishery.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.2
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• pp.127-135
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• 2009

The performance of the waterjet system of 180 ton class fishing guard ship has been experimentally studied. A waterjet propulsion system has many advantages in comparison with a conventional screw propeller especially for high speed craft because of its good cavitation performance. Recently waterjet system has been applied to fishing boats and fishing guard ship because of avoiding a net problem although their speeds are not so high. This paper describes experimental procedure and analysis method of resistance and self-propulsion tests with a 1/14.46-scale model. Experimental results were analyzed according to ITTC 96 standard method. The full-scale effective power and delivered power of the ship were also analyzed and the full-scale speed predicted from the model test results shows a good agreement with the full-scale result from the sea trial tests.