• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.4
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• pp.340-346
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• 2020

In this study, the risk factors of coastal purse seine fisherman were analyzed through a survey of fishery workers of coastal purse seine fishery and the accident compensation insurance data of the fisheries workers of the National Federation of Fisheries Cooperatives (NFFC). The classified fishing operation accident data was analyzed through 4M (Man, Machine, Media, Management) model of the National Transportation Safety Board (NTSB) and the accident prevention measures were presented using Harvey's 3E (Engineering, Education, Enforcement) model. The rate of accidents on coastal purse seinens each year was 75.8‰, 36.7‰ and 74.8‰ from 2015 to 2017. The accident frequency resulting from slipping was the highest, and the risk of a contact with gear was low. When comparing each insurance data, the average value of the contact with gear accident was the highest. This research result is expected to be important data in identifying and preventing safety hazards of coastal purse seiner fisherman in the future.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.4
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• pp.277-291
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• 2020

In order to understand characteristics on bycatch of Korean tuna purse seine fishery, especially operations associated with Fish Aggregating Device (FAD) in the Indian Ocean, we conducted analyses related to bycatch by school association type (unassociated school, FAD associated school and log associated school) using the data collected by scientific observers from 2016 to 2018. The FAD used by Korean tuna purse seine fishery in the Indian Ocean was a drifting FAD, which belongs to non-entangling FADs according to the category proposed by the International Seafood Sustainability Foundation (ISSF). The target species of Korean tuna purse seine fishery are skipjack, yellowfin and bigeye tunas, accounting for 99% of the total catch. The ratio of bycatch was 0.97% in total catch and the discard accounted for less than 1%, indicating that most catch was retained on board. In terms of bycatch ratio by school association type, it accounted for 0.12% for unassociated school, 1.09% for FAD associated school and 1.25% for log associated school. As for the catch proportion of shark species by school association type, it accounted for 0.01% for unassociated school, 0.11% for FAD associated school and 0.10% for log associated school, which showed that unassociated school type was the lowest to affect bycatch of non-target and shark species. Given the proportion of bycatch compositions, however, it is considered that FAD associated school of Korean tuna purse seine fishery has less caught bycatch species of non-target and shark, compared to other fleets operating in the Indian Ocean.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.2
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• pp.107-117
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• 2012

Korean large purse seine fishery catches chub mackerel, sardine, jack mackerel, Spanish mackerel, etc. which are mainly pelagic fish species. The proportion of chub mackerel was 60% over in Korean large purse seine fishery. Sea surface temperature (SST) increased $0.0253^{\circ}C$ per year and total rising rate was $0.759^{\circ}C$ from 1980 to 2009 in the southern sea of Korea, where is mainly fishing grounds of Korean large purse seine. It was that p<0.01 level was statistically significant. It is northward movement that the center of fishing grounds of chub mackerel by Korean large purse seine fishery moved 4.57km/yr. It was rapidly northward movement about 7.1km/yr, 8.13km/yr to move Spanish mackerel and bluefin tuna fishing grounds. However, the fishing grounds of jack mackerel were moved further south in the 2000s than the 1980s. Catch of tunas and bluefin tuna consistently increased in Korean waters. There was a significantly positive correlation between SST and catch of bluefin tuna in the fishing grounds of Korean waters.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.1
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• pp.1-11
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• 2007

It is the basic studies for productivity improvement and laborsaving of purse seine fishery. Because the seine shape is apt to be transformed in seine shooting process due to the effect of tide, this study is intended to establish 4 steps, whose flow velocity are 0, 2, 4 and 6cm/sec, in flume tank and perform the experiment to review the character. We used two model seines designed on the scale of 1 to 180 based on the power block seine, which is the mackerel purse seine generally used in the near sea of Jeju Island and triplex seine, which is the mackerel purse seine of one boat system fishing expected in the future, for the experiment, analyzed of the sinking movements on the two seines and its results are as follows. In the setting over the flow velocity 6cm/sec, experiment was impossible because of flying and transformation of seine were severe. The sinking movements of P seine and T seine generally showed linear phenomenon and the sinking speed showed gentle curve shape. Sinking tendency was distinguished by existence of flow velocity. When there is flow velocity, it showed the phenomenon that it sinking by similar type. Although sinking depth and sinking speed did not show distinguished classification, P seine shows bigger than T seine. When there was in flow velocity, the elapsed time(Et) and sinking depth (PDp, TDp) of P seine and T seine can be shown such experimental equations as PDp=(0.21V+4.96)Et-(0.62V-0.10) and TDp=(0.19V+4.95)Et-(0.72V+0.34). When there was in flow velocity, the elapsed time and siking speed (PSp, TSp) of P seine and T seine can be shown such experimental equations as $PSp=-0.11Et^2+1.42Et+1.75\;and\;TSp=-0.11Et^2+1.41Et+1.37$.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.53 no.3
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• pp.228-239
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• 2017

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 (l) and diameter (d) 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 ($C_d$) also increased with increasing d/l. It can be expressed as $C_d=3.71499(d/l)+0.76595$ at a current speed 0.4 m/s and $C_d=4.30324(d/l)+0.69056$ at a current speed 0.5 m/s. Compared with previous studies, drag coefficient values were similar to knotless net of similar d/l 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.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.2
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• pp.107-116
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• 2021

The breakdown of the Korea-Japan fishing negotiations since 2016 has made it impossible for many domestic fishing vessels to operate in the Japanese EEZ water, and large purse seine fishing vessels are one of them. Mackerel is a highly migratory fish species, circulating in the East China Sea, South Sea, West Sea and East Coast throughout the year, and goes through a period of wintering, spawning, growth and feeding migration. In this study, in order to find out the dependence of large purse seine fishing vessels on mackerel fishing in the Japanese EEZ waters, we analyzed the characteristics of mackerel by large purse seine fisheries in the Japanese EEZ waters from 2010 to 2016. The catch and fishing details were investigated. The total catch of mackerel by large purse seine fishery, the average catch rate of mackerel in Japanese EEZ is 4 percent per year. The amount is estimated at 10.2 billion won per year. Although there was an effect, it was not judged to be a significant factor, and it was found that the amount of catch and fish price in the domestic waters had a greater influence on the total catch than the Japanese EEZ waters.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.1
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• pp.12-27
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• 2007

This fundamental studies on for the productivity improvement and laborsaving of purse seine fishery. Given the difficulty posed from the distortion of net shape caused by the external forces, such as tide, at the time of shooting and pursing, we set the 4 steps of 0, 2, 4 and 6cm/sec in flow velocity in the flume tank for the experiment in order to examine those characteristics. We used two model seines designed on the scale of 1 to 180 based on the power block seine, which is the mackerel purse seine generally used in the near sea of Jeju Island and triplex seine, which is the mackerel purse seine of one boat system fishing expected in the future, for the experiment, and interpreted the characteristics of several motion in water, such as the shape of seine, the change in tension and area during pursing and its the analysis results are as follows. Though the experiment could be conducted up to 6cm/sec of flow velocity that was defined, the experiment could not go on because of the severe distortion in the seine at the flow velocity in excess of 6cm/sec. As for the depth of leadline and reduction rate of side area of seine when the pursing is connected, P seine turned out to be slightly higher than T seine, and the hauling speed and reduction rate of upper area of seine were found similar to each other. The correlation between the hauling time (Ht) and depth of lead line (Dhp, Dht) of P seine and T seine can be expressed by the equation, that is, Dhp=(0.99Pt-7.63)Pt+69.01, Dht=(1.03Pt-7.73)Pt+66.74. The correlation between the hauling time and hauling velocity (Hpp, Hpt) can be expressed by the equation, that is, $Hpp=-0.06Ht^2+0.88Ht+0.78,\;Hpt=-0.05Ht^2+0.81Ht+0.98$ here, Pt is pursing time. And the correlation between the pursing time and the reduction rate of side area (sArp, sArt) can be expressed by the equation, that is, $sArp=-0.48Pt^2+14.79Pt-16.74,\;sArt=-0.45Pt^2+14.56Pt-16.48$. The reduction rate of upper area of seine (tArp, tArt) can be expressed by the equation, that is, $tArp=0.34Pt^2-0.66Pt-0.74,\;tArt=0.34Pt^2-0.27Pt-1.80$. In addition, the correlation between the pursing time and tension of purse line (Tep, Tet) can be expressed by the equation, that is, $Tep=2.79Pt^2+2.26Pt-0.60,\;Tet=2.14Pt^2+8.08Pt-27.50$.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.1
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• pp.82-93
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• 2019

The International Labor Organization (ILO) selected fishing as the most dangerous group of jobs in the world, and it is well known in Korea as a 4D industry. Offshore large purse seine accounts for the largest portion of the fishing industry in the coastal region with high death rate and the accident rate. The repeated disaster rate survey by the Korea Maritime Institute (KMI) shows offshore large purse seiner is the highest at 22.3 percent and coastal gill nets and offshore stow net are following at 12.4 percent and 11.9 percent in order. Therefore, risk factors occurring in offshore large purse seiners were analyzed based on data from the National Federation of Fisheries Cooperatives (NFFC) for three years from 2015 to 2017 and 4M (Man, Machine, Media, Management) 3E (Engineering, Education, Enforcement) techniques were used to provide a safe fishing environment. The number of accidents on offshore large purse seiners each year was more than 150, and the number of accidents on every fishing boats was as high as 17 percent in 2015. If the accident rate and the risk level were divided by insurance, the accident resulting from contact with machinery was the highest, and the risk of a contact with gear was low but frequently occurring. This was caused by collisions and contact with gear in situations where death and disappearance risk are not high, and accident types in situations where death and loss risk are considered to be contact with machinery, falls or other accidents. Through these analysis techniques, the frequency and risk of each type of accident on a offshore large purse seiners can be demonstrated, and it is expected to raise awareness of a safer fishing environment and contribute to the reduction of accidents.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.1
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• pp.61-70
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• 2015

In an attempt to improve the maneuvering character of hull form renovated tuna purse seiner. A renovation was carried out on the 3 tuna purse seiner fishing vessel. To grasp the progress of maneuvering and resistance on ship B (730 ton class), new bulbous bow was only attached. The ship A (740 ton class) and C (600 ton class) were modified for new bulbous bow, enlarged slipway and rudder. And then the zigzag and the turning test were carried out. According to the turning test, the advance and the tactical diameter were improved very much for the modified ship. The sea trial was carried out for the original and modified ship A. It is showed that the results of sea trial corresponded with that of the tank test on the whole. In the result of the zigzag test on ship B, the turning ability was improved very much, but the yaw checking ability was deteriorated in just some degree. In the result of the zigzag test on ship C, the turning ability and yaw checking ability were remarkably improved. Ship C was greatly improved among the three ships for the maneuvering character of modified hull form.

• Archives of Plastic Surgery
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• v.36 no.3
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• pp.322-326
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• 2009

Purpose: Severe type of inverted nipple (cannot be pulled out above the areola plane by manipulation, grade III) usually cannot be corrected by a relatively simple purse - string suture technique. Most patients want to avoid visible scars. To treat the severe case and avoid visible stigma, we introduce this invisible dermal flap method. Methods: This new surgical procedure makes bilateral incisions on the sidewall of nipple and dissections vertically to free the ducts from the contracted tissues. After dissection, the tunnel is formed. We insert "dermal flaps" into the tunnel underneath nipple base. Then through - and - through sutures are performed vertically (6 o'clock and 12 o'clock positions) and the purse - string suture is added with 4 - 0 nylon. Results: We had treated 35 primary inverted nipples (grade III) in 27 patients and 13 recurrent nipples in 7 cases. The results were excellent in 45 nipples (93.7%). All but 3 recurred cases was fully or very satisfied with the results. Conclusion: This technique is effective for the correction of severe inverted nipples and recurrent cases. We can avoid the visible scars on the areola surface.