• Journal of the Society of Naval Architects of Korea
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• v.36 no.1
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• pp.1-14
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• 1999

The simulation results of a small racing boat racing in steady wind and encountering waves are investigated by Nakato & Ha. The simulation of the race running is realized by referring the measured data of boats and the motions are described by a set of equations of motion in six degree of freedom as generals used in the aerodynamics. In this report, Nakato & Ha's motion equations are modified by equipping the flaps to generate the lift. The flaps of the racing boat could restrain considerably the boat from capsizing caused by superposed external disturbances, wind and encountering waves.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.59 no.3
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• pp.271-278
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• 2023

This study aims to analyze the income structure, cost structure, and profit structure based on data related to the business performance of the boat seine fishery from 1990 to 2020, and to identify the direct and indirect factors affecting fishery profitability through panel regression analysis. The main analysis results are as follows. First, it was found that fish catch has a significant amount of impact on fishery profitability, which is a key factor in improving the profitability of anchovy boat seine fishery. Second, it is necessary to develop carbon-reduced fishing gear, develop fleet-reduced fishing gear, and improve the operating system in order to increase fishery profitability for the short run. Third, it is necessary to create and maintain sustainable profitability for the long run, the continuous fishing vessels buyback program, an active responses to climate change, and the follow-up investigations about marine aggregate extraction in the south sea EEZ are needed.

• Journal of Ship and Ocean Technology
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• v.9 no.2
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• pp.1-10
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• 2005

A light-weight cantilever type towing carriage was devised and installed in the towing tank at Seoul National University. Wireless measurement devices were also provided for appropriate data acquisition during high-speed towing tests. With the new carriage system, a series of model tests were performed to investigate the hydrodynamic characteristics of the racing boat in the towing tank and the resistance test results had sufficient accuracy so that they could be used in the development of a high speed planning hull.

• Journal of Ocean Engineering and Technology
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• v.11 no.3
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• pp.95-99
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• 1997

In these days, the pollution of marine environment near island at Korean coastal zone caused by the trash human waste and livestocks excreata become intensified. One of the most economic and efficient way to prevent this pollution problem is to set up island circulating incineration system. In this paper, the result of feasibility study on the application of turtle boat hull form to the incinerating vessel has been summarized especially for the resistance and course keeping point of view.

• Journal of the Society of Naval Architects of Korea
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• v.32 no.4
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• pp.1-8
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• 1995

This paper is presented determination of the hull form factors about a high speed coastal fishing boat using Fuzzy modeling. That is, the estimation curves of total resistance & EHP(Efficiency Horse Power) are induced by Fuzzy modeling algorithm from data of accumulated hull form factors and are compared with the results of model test. Also, the estimation curves of total resistance & EHP are utilized efficiently in determination the hull form factors about a high speed coastal fishing boat.

• Communications for Statistical Applications and Methods
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• v.31 no.5
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• pp.487-496
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• 2024

In this paper, we propose a data-driven procedure to segment a binary sequence as an alternative to the popular hidden Markov model (HMM) based procedure. Unlike the HMM, our procedure does not make any distributional or model assumption to the data. To segment the sequence, we suggest to minimize the least square distance from the observations under total variation regularization to the solution, and develop a polynomial time algorithm for it. Finally, we illustrate the algorithm using a toy example and apply it to the Gemini boat race data between Oxford and Cambridge University. Further, we numerically compare the performance of our procedure to the HMM based segmentation through these examples.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.644-653
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• 2002

Sizes of coastal squid jogging boats, their light source output for fishing lamps and daily catch data were collected, for a purpose of evaluating factors on fishing boats, which affect to the squid catch, from four fishing ports (Hakodate, Sado Island, Noto and Tsushima) in Japan. The catch amount was increased as boat sizes and their light source output of fishing lamps were increased up to 100$\~$200 kW class and 11$\~$15 gross tonnage class. The relationship between catch per unit efforts y (box/machine/day), gross tonnage x_{1}, (GT) and light source output for fishing lamps x_2 (kW) is expressed as following formula; $y=4.091+0.18x_1+0.0019x_2$. Thus, 0.1819 boxes of squid catch can be expected, when light source output for fishing lamps increases for 1 kW $(x_2{\leq}200)$ and boat size 1 GT ($x_1\leq15$). It is considered that the boat size which created a shadow area under the jigging boat, is important factor affecting to catch amount, Because larger shadow area created by bigger boat has a possibility to let more squid stay there.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.232-234
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• 2012

NMEA2000 international standards was developed for real-time communication among sensors and devices in ships. This paper describes analysis of NMEA2000 network protocols and implementation of a gateway for wireless data services in NMEA2000 networks. For scalability of the network, developed gateway didn't participate in NMEA2000 network but simply relayed data between wireless devices and the network.

• Journal of the Korean Institute of Navigation
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• v.1 no.1
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• pp.45-62
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• 1977

The advanced researches of the ship's motion in the seaway can predict the heaving, pitching and slamming of ship's motion. The researches as of today are that of displacement type such as a small typical fishing boat and U, UV and V bow ship forms under low speed. In recent day, the study of behaviours of high speed planning boat in the regular waves has been carried out by Bessho [5]. The calculation about behaviours of a high speed vessel in the longitudinal regular waves is calculated by Ordinary Strip Method in this paper. The data of the results were discussed and compared with Bessho's results. The conclusions deduced from this study are as follow, (1) The acceleration of motion calculated by the O.S.M. is similar with Bessho's data for the Fn 0.5 (2) The amplitudes of the behaviours of motions take peak at 1.0<λ/L<1.4.

• Journal of the Korean Institute of Navigation
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• v.3 no.2
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• pp.1-19
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• 1979

The advanced researches of the ship's motion in the seaway can predict the heaving, pitching and slamming of ship's motion. The researches as of today are that of displacement type such as a small typical fishing boat and U, UV and V bow ship forms under low speed. In recent day, the study of behaviours of high speed planning boat in the regular waves has been carried out by Bessho [5]. The calculation about behaviours of a high speed vessel in the longitudinal regular waves is calculated by Ordinary Strip Method in this paper. The data of the results were discussed and compared with Bessho's results. The conclusions deduced from this study are as follow, (1) The acceleration of motion calculated by the O.S.M. is similar with Bessho's data for the Fn 0.5 (2) The amplitudes of the behaviours of motions take peak at 1.0<λ/L<1.4.