• 수산해양기술연구
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• 제53권1호
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• pp.1-11
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• 2017

Fishing pots are one of the important fishing gears in our coastal and offshore fisheries. In terms of a sustainable use of marine resources, there are concerns about the ghost fishing by lost pots. It is reported that 10 to 70% of the pots are abandoned or lost annually. This study is to compare the catching efficiency of drum type whelk pots that are made of biodegradable nets to those made of the ordinary nets, in the eastern coast of Korea. Five types of drum pots were used with combination of biodegradable nets and ordinary (PA, PE) nets applied to the main and funnel parts of the pots: pots with biodegradable nets (Bio+Bio); pots with PE net (PE+PE); pots with body and funnel made of biodegradable nets and PE nets respectively (Bio+PE); pots with body and funnel made of PE nets and PA nets respectively (PE+PA); pots with body and funnel made of PE nets and biodegradable net respectively (PE+Bio). Field experiments were conducted from June $18^{th}$, 2015 to August $7^{th}$, 2015 using a commercial fishing vessel in the Uljin waters on the eastern coast of Korea. Two fleets of pots with one hundred in each, 20 pots of each type, were casted for 8 to 15 days to analyze their catching efficiency. The catch of target species, whelks, was 202,563.0 g with catch rate of 38.7% of the total catch, while the bycatch was 320,709.7 g with the rate of 61.3% of the total catch. The catch of whelks was the highest in the Bio+PE pots (46,020.3 g), followed by the Bio+Bio pots (42,027.5 g), the PE+Bio pots (41,849.9 g) and the lowest being PE+PE pots (38,054.2 g). Compared to the conventional pots, the pots with biodegradable nets on the body or entrance part had slightly higher catch rate for both the target species and the bycatch. The PE+PE had the lowest catch rate. There is no significant difference in catch between the pots with biodegradable nets and the ordinary nets for the target species such as Buccinum opisthoplectum, Neptunea eulimata, Buccinum striatissimum. Consequently, using biodegradable nets for the conventional whelk pots can reduce ghost fishing by lost gears while keeping the performance of the pots.

• 수산해양기술연구
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• 제55권1호
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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.

• 수산해양기술연구
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• 제56권2호
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• pp.155-162
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• 2020

The adjudication of Korean Maritime Safety Tribunal (KMST) was analyzed to collect basic data to identify the cause of the risk that did not appear in the current data provided by the fishermen's occupational accidents of the National Federation of Fisheries Cooperative (NFFC) in stow net fishing vessel from 2015 to 2019. The personnel's carelessness was the most common in 29 out of 33 accidents (87.9%), followed by 25 cases (75.8%) of inadequacy of instructions, 24 cases (72.7%) of inadequacy of education on hazard factor, 20 cases (60.6%) of no personal protection equipment, 18 cases (54.5%) of poor guard, 17 cases (51.5%) of inadequacy of work method, 16 cases (48.5%) of absence of emergency stop button, 14 cases (42.4%) of work practice of poor safety precautions that affected more than 40% of all accidents as accident causes. These causes had a strong influence on each other, and the ratio of accident causes is high. With this relationship, accidents can be prevented or the severity of human injury can be reduced if types of accident process can be estimated with a scenario, and the key points before the accident in the scenario are switched to safe points.

• 대한조선학회지
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• 제7권1호
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• pp.57-78
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• 1970

The Korea inshore fishing boats are the size up to 30G.T., and their construction commonly employs the traditional wide wooden planking. Nevertheless, the hull forms have been developed with chine-type straight-framed sections which give developable surface party, but not on the whole: especially not on the whole portion of the hull are preferable for them. Considering many merits in the boat construction, the author, excluding cases of the FRP construction by hand lay-up or spray-up method and of the ferro-cement construction, finds out no reasons to depart from the chine-type hull forms of a developable surface in future development of their hull forms, too. In this report, the author proposed new designs of the developable hull surface for four typical boats forming the main structure of Korean inshore fishing fleets; 5G.T.-class multi-purpose boat, 10G.T.-class angling and longlining boat, 20G.T.-class drift and gill netters, and 27G.T.-class stow netters, and presented the tank test results on their propulsion resistance. The tank test had two purposes; one is to present the powering schedule of the new designs and the other to investigate the resistance characteristics of this kinds of boat in comparision with those of equivalent round-type boats at operational speed ranges. Between the both types of the boat no material differences in powering are expected. Hence, the author is confident of that saving in the construction cost of the developable hull over that of the round-type boat may result in considerable contribution to the over-all boat economy.

• 한국지반공학회논문집
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• 제28권9호
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• pp.47-55
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• 2012

본 연구에서는 폐어망 보강형식에 따른 폐타이어-저회 혼합토의 전단특성을 고찰하였다. 실험에 사용된 혼합토는 폐타이어(분말입경 2mm~10mm)와 저회를 동일한 무게비로 구성하였으며, 준비된 혼합토에 폐어망 보강 시 층수와 겹수를 달리하여 보강함으로써 5종류의 시편(무보강 혼합토, 1층 혹은 2층 보강 혼합토, 2겹 1층 혹은 2층 보강 혼합토)이 만들어졌다. 직접전단시험을 수행한 결과 폐어망 보강 혼합토의 역학적 특성은 폐어망 보강 층수와 보강 겹수에 크게 의존하는 것을 알 수 있다. 폐어망 보강 층수와 보강 겹수가 증가함에 따라 혼합토의 전단강도와 내부마찰각은 증가한다. 이것은 보강된 폐어망과 혼합토 입자간의 마찰 및 억물림 효과에 기인하는 것으로 판단된다.

• 수산해양기술연구
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• 제58권3호
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• pp.199-204
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• 2022

The Pacific giant octopus (Enteroctopus dofleini) is one of the most important species in the East Sea fishery of Korea. The annual production of Pacific giant octopus in 2021 was 3,880 metric ton between Gangwon province and Gyeongsangbuk province. Most of the fishing gears for the octopus fishery were based on behavioral properties such as thigmotaxis and chemotaxis. Wooden octopus box is also one of the fishing gears, which is application of thigmotaxis for the octopus capture in fishing industry. In this study, the tank experiments were designed to examine the behaviour and the effect of surface roughness to the infiltration of the octopus quantitatively. Three different types of octopus boxes were used for the experiments with different surface roughness on the average of 701.6 ㎛, 141.7 ㎛ and 2.09 ㎛ for each gear. 22 trials were conducted from June to September 2021. The normality of the experiments was tested using Shapiro-Wilk normality test (p-value < 0.05). The significance of results was conducted by Kruskal-Wallis rank sum test (Chi-squarded = 21, Degree of freedom = 3, p-value < 0.05). The use of wooden octopus box with rough surface was found to enhance the catch efficiency and observe infiltration behaviour of the octopus frequently.

• 한국생활과학회지
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• 제21권2호
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• pp.315-329
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• 2012

The purpose of this study was to examine clothing purchase behavior of sports participants based on outdoor sports types and sports participation motivation. The research was conducted with the use of a self-administered questionnaire. A total of 703 respondents between the ages of 25 and 55 participated in the research through an internet survey. Motivation for participation in particular sports was comprised of four factors: impress others, mental rejuvenation, social interaction, and health maintenance/improvement. Perceived benefits of clothing choice were categorized into three factors: brand/fashion pursuit, positive image pursuit, and practicality pursuit. Outdoor sports activities was categorized into six types, climbing, jogging, cycling, fishing, golf, and others including ball games. Each sports group presented differences in demographics, sports motivation factors, and benefit factors. Four segments were identified based on sports participation motivation: active group, social group, health and revitalization group, and inactive group. The active group considered three clothing benefits and 14 evaluative criteria as being the most important among the four segments, indicating the major target market for outdoor sportswear brands. On the other hand, the members of inactive group showed passive attitudes toward clothing purchasing behaviors. This study discusses the results of this research within the context of the managerial implication for outdoor sports marketers.

• 수산해양교육연구
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• 제25권4호
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• pp.766-774
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• 2013

Biodegradable polybutylene succinate(PBS) is a kind of environmentally friendly plastics for fisheries, because it can mitigate the ghost fishing problem caused by gill-net and trap fisheries. To evaluate durability of PBS monofilament, each of different diameter 3 types of monofilaments were spun and exposed to 56 month outdoor and then their gravity, modification of surface, breaking strength, and elongation were analysed. The gravity of PBS monofilament was estimated to be approximately 1.24 when spinning ratio from 4.8 to 6.1. PBS monofilaments did not show any crack after 56 month exposed to outdoor and load-elastic elongation curve was showed sigmoid type. Decreasing ratio of elongation was appeared in the thinnest monofilament 0.2mm diameter and breaking strength was in the thickest monofilament 0.4mm diameter. Breaking strength and elongation at break were decreased rapidly after 48 month exposed to outdoor. Breaking strength reduced linearly after 48 month exposure, while no such linear relationship was found in the case of elongation at break. In results, it was investigated that the durability of PBS monofilament nets for gillnet and trap were 24, 50 month when keep to land, respectively.

• 한국해안해양공학회지
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• 제16권1호
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• pp.1-9
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• 2004

본 연구에서는 원전어항에서 채용하고 있는 강제 부방파제에 비해 소요재료량의 변화가 크지 않은 범위에서 전후연직판의 위치와 형식의 변화 및 수평판의 부착 유무에 따른 여러 형식의 부방파제에 의한 투과율과 반사율을 Green 함수법으로부터 계산한 결과에 기초하여, 원전어항의 강제 부방파제보다 단주기파 및 장주기파를 보다 효과적으로 제어할 수 있는 새로운 형식의 부방파제를 검토하였다. 이로부터 연직커튼판 하부에 수평판을 부착한 형태의 부방파제가 파랑제어기능이 우수한 것으로 판명되었고, 이는 원전어항 부방파제보다 파랑제어기능이 탁월하다는 것을 알 수 있었다. 또한, 본체에 부착된 전후연직판 및 수평판의 크기와 간격을 조절함으로써 적합한 투과파를 얻을 수 있다는 것도 알 수 있었다.

• 수산해양기술연구
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• 제57권1호
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• pp.1-9
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• 2021

Trawl fishing is a fishing method in which a large, motorized trawler tows a bag-shaped net to catch fish living at the bottom or middle layers. For a trawl gear, it is of utmost importance to select the gear size and towing speed suitable for the effective horsepower (EHP) of the trawler in the design stage. In general, the power required to move an object is proportional to the product of the object speed and resistance; therefore, there are various choices for the gear resistance and towing speed given the effective horsepower of the trawler. However, there have been few studies on the gear design of an appropriate scale for the towing speed given the effective horsepower of the trawler. In this study, the resistance and shape of three types of midwater trawl gears were analyzed using SimuTrawl, a computer simulation tool. In addition, the relationship between the propulsion force and speed of the ship was clarified when the size and effective horsepower of the trawler were determined. Finally, we suggested the relationship between the towing speed and the resistance of the gear when the trawler towed the net was investigated, and a specific method of selecting the gear size according to the towing speed.