• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.03a
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• pp.203-208
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• 1998

Materials of the Frame hole in fishing trackle reel is made up a number large and small holes. Thus, it is difficult to effective machining. Abrasive flow machining(AFM) is useful to polish a internal or external surface of the 3-dimensional shape parts, which are used in many fields such as aerospace, automative, semi-conductor, and medical component industries. The machining process is that two hydraulic cylinders, which are located face to face, enforce abrasive media to the passage between workpiece and tooling parts alternately, and then the abrasives include in the media pass the passage and polish the surface of workpiece. The media which is made of polymer and abrasives plays the role of the tool for deburring or polishing complex shap workpiece by its viscoelastic characteristics. In this study, the abrasive media for abrasive flow machining was made by mixing viscielastic polymer with alunina and silicon carbide abrasive. Also, we present AFM device design and preliminary results of an investigation in to some aspects of the AFM process performance in fishing trackle reel.

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.4
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• pp.63-69
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• 2011

Hull forms for catamaran type small fishing boat powered by electric motor are newly developed by experimental approaches. Model tests for two hull forms having different length are made at circulating water channel. Resistance performance and wave patterns are compared to carry out an analysis of the effect of extension of main body. The results show that the extension of main body can give better resistance performance above a certain velocity.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1994.06c
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• pp.69-69
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• 1994

• Journal of Korean Society of Rural Planning
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• v.26 no.1
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• pp.23-38
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• 2020

This study is aimed at the deduction of the important priority factors by setting the comprehensive rate in each of the economy, sociability and environmental areas for the sustainable development of fishing villages. As the research methods, review of domestic and overseas literature and Delphi questionnaire survey on experts, and hierarchical structure analysis were executed. Accordingly, this study is aimed at providing the basic data at the time of establishing plans by assessing the level of importance and priorities for each item through the deduction of the elements necessary for the fishing village plan. Key results of the study are as follows. First, as the results of review of domestic and overseas literature related to sustainability indices of fishing villages, a total of 50 items in the areas of economy, sociability and environment were deduced. Second, validity for each area was confirmed through Delphi questionnaire survey on experts. Third, as the results of factor analysis conducted on the basis of the hierarchical structure analysis for detailed items for each sector, 3 factors in the economic area, 2 factors in the social area and 3 factors in environment area were deduced. Fourth, as the results of the relative importance of the higher tiers, economic sector (0.528) displayed results that are more than 2 times higher than the social (0.261) and environmental (0.212) sectors. Establishment of foundation for independent competition (0.105), balanced development of small fishing village (0.086) and population engaged in economic activities in comparison to the fishing village population (0.077) were analyzed as the most important detailed items. Based on these results, experts pointed out that the economic sector is most important for the sustainable development of fishing village and, in detail, priority must be placed on the balanced development on the basis if the extent of independence of the fishing villages, and emphasized activation of residents engaged in economic activities in fishing villages in order to support them. That is, in order to increase the level of independence of the fishing villages, it was determined that there is a dire needs for expansion of diversified specialized businesses and infrastructural facilities through agreement by the residents capable of economic activities, and means of activating fishing villages through securing of budget at the local autonomous government level to provide support for the residents.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.5
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• pp.505-511
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• 2023

In the present study, a deep learning model was established to predict the motion response of small fishing vessels. Hydrodynamic performances were evaluated for two small fishing vessels for the dataset of deep learning model. The deep learning model of the Long Short-Term Memory (LSTM) which is one of the recurrent neural network was utilized. The input data of LSTM model consisted of time series of six(6) degrees of freedom motions and wave height and the output label was selected as the time series data of six(6) degrees of freedom motions. The hyperparameter and input window length studies were performed to optimize LSTM model. The time series motion response according to different wave direction was predicted by establised LSTM. The predicted time series motion response showed good overall agreement with the analysis results. As the length of the time series increased, differences between the predicted values and analysis results were increased, which is due to the reduced influence of long-term data in the training process. The overall error of the predicted data indicated that more than 85% of the data showed an error within 10%. The established LSTM model is expected to be utilized in monitoring and alarm systems for small fishing vessels.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.6
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• pp.604-609
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• 2012

Our country has experienced some difficulties with clean up operation of massive marine oil pollution due to the lack of oil spill response equipments. And there was the case that a fishing vessel performed clean up operation had not received any proper payments because of its inefficient oil spill response operation. Thus, it is important to develop an efficient oil recovery equipment for small vessel and adopt it as a part of oil pollution prevention policy. These efforts could prepare oil spill response equipment in advance and use a fishing vessel registered in the affected area by massive marine oil pollution. Therefore, this study examines and adopts a suitable subject vessels as a first step for developing oil recovery system fitting with small vessels for national use.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.3
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• pp.199-206
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• 2005

As the basic study about improvement of yellow croaker drift gill net fishing implement and development of the fishing system, this study drew problem after synthetically analyzing hauling system of yellow croaker drift gill net used in the coast of Chuja Island and tested several characters and analyzed in hauling process with 5 step net hauler model for improving the problem. The analysis results are as follows. When the angle between axises of drum centers was small, it showed the tendency that hauling time was fast. Hauling time was faster when drum was 5 step rather than 3 step. When drum was 5 step, slippery phenomenon was small and hauling was stable. Tension was larger when drum was 5 step rather than 3 step. When drum was 5 step, the range of change of the maximum and minimum value was small and hauling was stable. When drum was 3 step, there was following formula between hauling time ($Ht_3$) and angle between axises of drum centers ($A_g$) $Ht_3$ : ($7.15Hs^{-0.81}$) $A_g^{-0.81}$, when drum was 5 step there was following formula.$Ht_5$ : ($6.45Hs^{-0.75}$) $A_g0.10$, here, Hs is hauling speed. When drum was 3 step and hauling speed was 28cm/sec, tension was $T=0.08A_8^3-1.60A_g^3-0.49A_g+369.56(r=0.99)$, when drum was 5 step, tension was, $T=-0.01A_g^3+1.96A_g^2-34.05A_g+414.58$ (r-0.99), here, T was tension(g).

• Journal of Ocean Engineering and Technology
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• v.33 no.6
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• pp.495-503
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• 2019

Approximately 90,000 ships are registered in South Korea, and about 80,000 of these ships are used in domestic shipping. Among these, 84% are small ships, such as a fishing vessels that weigh less than 20 tons and are made mostly of an FRP (Fiber Reinforced Plastics). When this fact is taken into account, the greenhouse gas emissions that are released per ton of a composite vessel are sizeable. In this study, the laminated structures of an FRP fishing vessel, many of which currently are being built in Korea, were analyzed by ISO (International Organization for Standardization) and international design rules, and the structures of the hulls are lightweight with optimum glass fiber mass content as determined by the laminate weight minimization algorithm. As a result, it was confirmed that the laminations of the vessels in accordance with the Korean rule could have 6.4% to approximately 11% more design margin compared to the requirements of ISO and other international rules. And the case study of the application of the laminate weight minimization algorithm showed the possibility of reducing the weight of the hull bottom plating by as much as about 19.32% and by as much as about 18.06% in the overall structure.

• Journal of Agricultural Extension & Community Development
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• v.22 no.4
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• pp.405-421
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• 2015

Agro-fishing villages of agriculture and fishery are suffering deepening gap with urban areas due to depreciation from their products market opening pressure. They are facing problems of decreasing and aging population, poor settlement environment, etc. and losing their vitality for their low productivity and lack of young labor force. These issues of agro-fishing villages of agriculture and fishery are divided in so various items and classes that it is plausible to approach in a way to connect each issue in a small frame of each by selecting sub topics according to each item and each class rather than to solve the issues in a large frame. Chungchungnam-do is approaching the issues through 3 agro innovations(agro fishery, agro fishing villages, agro fishing people) in local government level and Durae enterprises are solving local problems through the self supporting residents' community business by utilizing local resources. This study is to draw clues and solutions to vitalize agro fishery villages through community businesses by detailed reviews and research on cases of Durae enterprises' characteristics and their vitalizations and provide a new alternative plan to agro fishery villages losing their vitality and demolishing their communities.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.11
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• pp.1025-1030
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• 2016

The big problem of accidents at sea is negligent watch, it causes collision, fender bender, stranding, rollover, and sinking of fishing vessel. Most accidents happens without an eyewitness, it is difficult to identify the cause of the accident. VDR(: Voyage Data Recorder) is needed to identify a cause of the accident, the VDR is not usually used for fishing vessel because of high cost. Thus, this paper designs and develops a VDR system for fishing vessel. If the system is used, cause of a sea accident can be quickly identified. Also, a VDR system can be used for appropriate measures to fix a cause of the accident. Finally, it also can be helpful to prevent maritime accidents.