• 해양환경안전학회지
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• 제6권1호
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• pp.35-45
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• 2000

The slipway, which is one of stern construction, is necessary for stern trawler to let fishing implements, such as fishing net, otter board and warp, go out effectively. It may be doubtable whether there is any possibility for deckwetness to occur because the slipway is obliquely in contact with sea surface. The author discusses any possibility for deckwetness through slipway of stern trawler in wind and waves. A 350 G/T class, ocean-going stern trawler is adopted for the present study. The stem trawler is particularly assumed to drift with fishing implements hung down the slipway due to internal or external accident during fishing operation in real sea. The author considers two factors as possibility for deckwetness to occur through slipway. One is mooring effect of fishing implements hung down the slipway under wind pressure, and the other is relative ship motion in vertical direction in waves. Through the numerical calculation, the author clarifies that there is thin possibility for deckwetness to occur from above two points of view.

• 수산해양기술연구
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• 제52권2호
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• pp.162-168
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• 2016

This study attempted to help determine Korean fishery policies by proposing improvement plans after examining the current regulations, fishing vessels, fishing gear and fishing methods of the middle sized trawl fishery in the East Sea for targeting only squid. In general, the size, engine horse power, and net length of the middle sized trawlers are between 50 and 60 GT, 1,200 and 1,600 PS, and approximately 165 m with four seamed trawl nets, respectively. While a jigging vessel attracted squids using lights, the trawler approached a jigging vessel. The trawler let the jigging vessel know its decision for fishing, and then jigging vessel rolled up jigs. The net of the trawler was casted at 45 degrees between the bow and the stern of the jigging vessel. Once the trawler towed close to the stern of the jigging vessel upon its passing of the jigging vessel, the bow of the trawler turned 45 degrees left again. Then, squid aggregations were entered into the net. When the cod end was passed a light vessel, the trawler hoisted the net up to the otter board. Then the trawler turned 180 degrees. It repeated three to five times of fishing operations as the previous method. We recommend that the regulations allow nineteen side trawlers to catch like stern trawler, as well as the cooperative trawler and jigging vessel operations.

• 수산해양기술연구
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• 제50권3호
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• pp.378-384
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• 2014

Trawlers are divided into stern and side types by the method of shooting and hauling net, but the latter is difficult to find beside Korea. In East Sea of Korea, the side type used to be in early 2000's, but it improved to stern type because of its inefficient operating method. The aims of this paper is to make clear the stability of the side trawler in the East Sea, and then confirm whether it satisfy the IMO rule or not, the degree of the transverse inclining angle of the ship when hauling net at hull side. In results, the stability of the ship in initial inclining range satisfied the IMO rule and the domestic rule, but not satisfied those rule in over the range. The limit load of the ship that was coincide with the angle of beam end in hauling net at side was about 26 tons, 18 tons in normal sea condition and storm warning condition respectively. The transverse inclining angles of the ship in hauling net were much higher from 3.3 to 5.5 times than the longitudinal inclining angle of the stern trawler, although those angles were slightly changed with depending on the loading and sea condition.

• 수산해양기술연구
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• 제54권3호
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• pp.239-245
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• 2018

International Maritime Organization (IMO) has established standards for ship manoeuvrability and applied these standards for vessels over 100 meters in length that built since 2004 (IMO, resolution MSC.137[76]). These standards are no exception to fishing vessels. In this study we carried out a manoeuvring simulation of the new model ship (Stern trawler) of fisheries training ship of Pukyong National University based on Kijima's empirical formula. The formula takes into account of the effect of stern shape or does not take into account of the effect of stern shape. Also we checked whether the simulation results of turning motion of model ship meet IMO manoeuvrability criteria and then compared trajectories between the simulation results of model ship and the results of real sea trial test of the existing ship. In conclusion, Kijima's empirical formulas can estimate the manoeuvrability of fishing vessels at design stage approximately, it needs more parameters of fishing vessel own in case of expressing the manoeuvrability of fishing vessel accurately.

• 수산해양기술연구
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• 제40권1호
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• pp.65-72
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• 2004

This paper deals with an experimental study on the dynamical characteristics of ship motion during trawling job on the real sea. The experiments were carried out on the small stern trawler, and roll and pitch motion of the ship according to the wave directions were simultaneously recorded by P/C in the same sea conditions. From these data, the statistical properties and power spectra were obtained, and then the analysis of ship motion in trwal job was made. As a result, it was found that the pitch motions in trwal job were displayed low amplitudes on the whole, but the rolling motions were displayed high amplitudes relatively, and very high value on the beam and quartering sea especially. Also, the trial ship has a high extinction coefficient in the roll motion, compared with the rule of stability, but when wave height takes 2.5m over, it can induce the safety of ship to scare occasionally. Therefore, a usefull countermeasure for the safety of ship has to be made adequately.

• 수산해양기술연구
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• 제13권2호
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• pp.21-26
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• 1977

대서양(大西洋) Africa 연안어장(沿岸漁場)에서 조업중(操業中)인 태창수산(太倉水産) 소속(所屬) Stern trawl 선(船) No. 85 PARTO(499S)에서 사용(使用)하고 있는 PT-4 형(型) 어구(漁具)의 조정한계(調整限界) 및 적정(適正)한 예망속도(曳網速度)와 주기(主機)의 운전상태(運轉狀態)를 판단(判斷)하기 위(爲)하여 warp에 작용(作用)하는 장력(張力)을 측정(測定)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 어구조정(漁具調整)의 한계(限界)는 warp에 작용(作用)하는 장력(張力)의 크기가 약(約) 7,500kg, 강약(强弱)의 범위(範圍)가 약(約) 1,000kg을 초과(超過)하지 않는 것이 효과적으로 판단(判斷)했다. 2. 예망속도(曳網速度)는 주기(主機)의 효과적인 운전상태(運轉狀態)와 어획성능(漁獲性能)을 고려(考慮)하여 $3.6{\sim}4.0$ knot로 판단(判斷)했다. 3. 주기(主機)의 운전상태(運轉狀態)는 유량소모(油量消耗)가 급증(急增)하는 r. p. m. 290, propeller pitch 각도(角度) 13.8를 초과(超過)하지 아니하고 $13.5^{\circ}{\sim}13.8^{\circ}$를 사용(使用)하는 것이 효과적으로 판단(判斷)했다.

• 수산해양기술연구
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• 제49권3호
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• pp.311-326
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• 2013

For providing a basic data concerning with a fishing deck layout design of a trawler the authors conducted the video observations about the working activities of crews on the deck in the different layout of two Korean coastal large stern trawlers (gross tonnage: 139). The winch of the trawler-A was installed on the aft of the fishing deck and the trawler-B, on the forward of the fishing deck. The work and activities of the deck hands on both trawlers were observed using the CCD (charge coupled device) camera installed on each trawler's deck for one month from August 3, 2010. The video data was analyzed by the hierarchical task analysis (HTA) method. In results, numbers of tasks to require deck hands during the hauling net and the casting net were 25 and 28 for the trawler-A and 27 and 48 for the trawler-B, respectively. The working processes were represented a same in both of the trawlers. Location for controlling the deck machineries, the location installed trawl winch, kinds of deck machineries, crew's custom for using deck machineries were the factor affecting to the number of the task. In the case of the improvement suggested in the results is carried out, the reduction percentages of the number of task in the trawler-A and trawler-B were estimated as 24.5% and 51.3%, respectively. Through this study it was found that the quantitative analysis is possible for the work processes, work methods and the work contents in the trawler. Also the suggestion for improving the fishing deck layout design of the trawler was possible by finding out the factors increasing the number of tasks and removing the tasks. We expect that the results of this paper are used as a basic data for designing the layout of deck machineries in the trawler in the future.

• 한국수산과학회지
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• 제2권2호
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• pp.173-178
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• 1969

(1) 1968년 6월 18일부터 7월 16일 사이에 일본수산청 어업조사선 Kaiyo-Maru에 승선 New Zealand 근해에서 trawl 실험을 행하였다. (2) 대형선미 trawl에 있어 예강초와 양강직전의 warp 장력간의 차는 입강어의 다과와는 상관이 없는 것 같다.

• 수산해양기술연구
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• 제52권4호
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• pp.339-346
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• 2016

The aim of this research was to the experimental data using statistical and spectral analyzing method to get the motion reponses of a stern trawler in operation states such as drifting, sailing and trawling according to the wave height. In drifting, the significant and the maximum valuer of roll in beam sea increased according to the wave height, but those of pitch decreased. The response and the period of peak of roll in beam sea were increased, but those of pitch decreased. In navigation, the significant and maximum values of roll increased remarkably according to the wave height, but those of pitch changed a little. The response of roll was highest in quartering sea, beam sea and then following sea, but those of pitch was highest in bow sea, head sea and then beam sea in the order of all wave heights. The period of peak of roll due to the wave height and the wave direction changed from 3.8 to 9.9 seconds, and those of pitch changed from 3.3 to 10.4 seconds. In trawling, the significant and maximum values of roll increased a little according to the wave height, but those of pitch increased significantly. The response of roll was highest in beam sea, bow sea and then quartering sea, but those of pitch was highest in head sea, following sea, and then beam sea in the order. The period of peak of roll due to the wave height and the direction changed from 6.6 to 10.9 seconds, and those of pitch changed from 6.7 to 11.2 seconds.

• 한국수산과학회지
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• 제18권1호
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• pp.1-7
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• 1985

본연구에서는 전개장치를 띠모양의 소형 범포들로 구성하는 띠전개범식 안강망어구를 고안하여 재래의 그들을 이용한 1/3 모형어구 및 그물을 개량한 실물어구를 각각 제작하여 실험하였던 바, 다음과 같은 결과를 얻었다. 1. 재래의 안강망어구의 축척비 1/3인 모형어구의 총저항 R(kg)을 실물로 환산하면 $R=5.6{\times}10^{3}V^{l.5}$ 또는 $R=3.5\frac{d}{l}{\lambda}_b{\lambda}_l\;V^{1.5}$로 주어진다. 단, V 유속(m/sec), d는 그물실의 직경, l은 그물코 다리 한개의 길이, ${\lambda}_b$는 그물아궁이의 뻗친 둘레(m), ${\lambda}_l$은 그물의 뻗친 길이(m)이다. 2. 모형실험에서 망고는 유속에 따라 거의 일정하며 옆줄 길이의 $83\%$ 정도로 유지하였다. 3. 망폭은 유속의 증가에 따라 서서히 감소하여 유속 1m/sec 일 때 모형실험에서는 뜸줄길이의 $90\%$정도, 실물실험에서는 $95\%$정도 유지하였다. 4. 어구조작은 선미식 트롤어선으로 행한 결과 전개장치의 선미경사로 통과가 여의치 않았고 장망시 선미경사로상에서 뜸줄, 발줄 및 옆줄이 뒤로 쳐져 엉키는 현상이 일어났다.