모형실험과 시뮬레이션을 통한 활어 이송용 예인 가두리의수직 및 수평 전개력 추정

박수봉 ( Subong Park ),이춘우 ( Chun Woo Lee ) 한국어업기술학회 2014 수산해양기술연구 Vol.50 No.2

Nowadays, consumption of fisheries products is increasing. There are several factors, one of which is a quantitative development through aquaculture. Another factor is an increase qualitative consumption of fish which require that fish be supplied alive. This requires a lot of technical effort to transport the live fish that have low survival rate(c.f. tuna and mackerel) in coastal waters and in the open sea. To develop a towing cage for transporting the live fish, model test in a circulate water channel and simulation by computer tool were carried out. In order to spread vertically, floats were attached at the upper part of the cage, and iron chains attached at the lower part of the cage. For horizontal spreading, kites were attached on the cage. The tension and spreading performance of the cage were measured. The result shows that the tension and reduction ratio of inside volume of the cage were tended to increase with increased towing speeds. The suitable operation condition in towing cage was 1.0 m/s towing speeds with vertical spreading force 8.7 kN, horizontal spreading force 5.6 kN; in this case the reduction ratio of inside volume of the cage was estimated as 25%.

활어 수송과 계약 체결상의 민사 책임에 관한 연구

박수봉(Subong PARK),임석원(Seok-Won LIM) 한국수산해양교육학회 2014 水産海洋敎育硏究 Vol.26 No.5

분해 가속화 조건의 해수 환경에서 Polybutylene Succinate 섬유의 분해거동

현유진(Yujin Hyun),박수봉(Subong Park),곽효원(Hyo Won Kwak),진형준(Hyoung-Joon Jin) 한국고분자학회 2021 폴리머 Vol.45 No.3

본 연구에서는 기존의 나일론 기반의 비분해성 어구를 대체하기 위하여 제조된 polybutylene succinate(PBS) 섬유의 해수 환경에서의 생분해성 거동을 관찰하였다. 또한 빠른 시일 내의 섬유의 생분해를 확인하기 위하여, 계면활성제 첨가 및 자외선 조사 방식을 분해 가속 조건으로는 선정하여 각 조건이 해수 조건에서 PBS 섬유의 생분해 거동에 미치는 영향을 확인하였다. 6개월간의 해수 환경에서의 생분해 실험에도 불구하고 무게 감소는 발견되지 않았으며 분해 정도는 분자량 감소 및 기계적 강도의 저하를 통해 예측이 가능하였다. 한편, 계면활성제의 첨가는 PBS 섬유 표면의 친수화를 진행하여 분해 균주의 흡착을 용이하게 하였으며 이는 분자량 감소에 큰 영향을 주는 것으로 확인되었다. 반면, 자외선을 조사할 시에는 섬유 표면에 미세 크랙을 발생시켜 기계적 강도의 저하가 명확히 발생하는 것을 확인하였다. In this study, the biodegradation behavior of polybutylene succinate (PBS) fibers manufactured to replace conventional nylon-based non-degradable fishing net was observed in seawater environment. In addition, in order to find the appropriate degradation acceleration condition, surfactant addition and UV irradiation were selected as acceleration conditions, and the effects of each condition on the biodegradation behavior of PBS fibers in seawater conditions were confirmed. Despite the 6 months of biodegradation experiments in the seawater environment, negligible weight loss was found, and the degree of biodegradation could be predicted through a decrease in molecular weight and mechanical properties. Meanwhile, the addition of a surfactant facilitated the adsorption of the degraded strain by hydrophilizing the surface of the PBS fiber, which was confirmed to have a great effect on the molecular weight reduction. On the other hand, when ultraviolet irradiation, it was confirmed that fine cracks were generated on the surface of the fibers, thereby clearly deteriorating mechanical strength.

첨가제가 나트륨 이온 전지용 고분자전구체 기반 하드카본 음극 표면에 형성되는 고체 전해질 내부상 특성에 미치는 영향

김하영(Hayoung Kim),윤승욱(Seung Uk Yoon),박수봉(Subong Park),진형준(Hyoung-Joon Jin) 한국고분자학회 2020 폴리머 Vol.44 No.1

고분자 전구체(polymeric precursor) 기반의 하드카본(hard carbon)은 난층 구조(turbostractic structure)와 난층 구조들 사이의 기공으로 이루어져 있기 때문에 나트륨 이온 배터리의 음극소재로써 약 300mA h g<SUP>-1</SUP>의 높은 용량을 나타낸다. 하지만, 불안정하게 형성된 고체 전해질 내부상(solid electrolyte interphase, SEI)의 영향으로 인해, 하드카본은 제한된 수명특성을 가진다. 이러한 문제를 개선하기 위해 적절한 첨가제를 찾는 연구가 진행되고 있다. 본 연구에서는 첨가제 fluoroethylene carbonate(FEC) 및 succinic anhydride(SA)가 하드카본의 수명특성에 미치는 영향을 관찰하고 원인을 조사하였다. 그 결과, 첨가제에 의한 필름 저항 증가로 인해 하드카본의 수명 특성이 저하되었다. FEC를 첨가한 전해질에서의 높은 필름 저항은 3.34 eV의 비교적 높은 배리어 에너지를 갖는 sodium fluoride 성분이 도입된 SEI 층 형성에 기인하였다. 반면, SA를 첨가한 전해질에서의 높은 필름 저항은 두껍게 형성된 SEI 층 형성에 기인한 것으로 두 첨가제의 필름 저항 증가 원인이 상이하였다. Polymeric precursor-based hard carbon with a disordered turbostratic structure has a high capacity of approximately 300 mA h g<SUP>-1</SUP> as an anode material for a sodium-ion battery. However, hard carbon has a limited cycle performance owing to the formation of unstable solid electrolyte interphase (SEI). To improve the cycle performance, several studies are underway to find suitable additives. In this study, the effects of fluorocarbon carbonate (FEC) and succinic anhydride (SA) on the life characteristics of hard carbon were investigated and the reasons were examined. All additives negatively affected the cycle performance because they increase film resistance. The high film resistance in the electrolyte with FEC was due to the formation of the SEI layer with the introduction of the sodium fluoride component with a relatively high barrier energy of 3.34 eV. On the other hand, the high film resistance in the electrolyte with SA was due to the formation of a thick formed SEI layer, and the reason of the increase in film resistance of the two additives was different.

모형실험과 수치해석을 이용한 저항 저감형 중층 트롤어구의 성능 해석

김지은 ( Jieun Kim ),이지훈 ( Jihoon Lee ),박성호 ( Seongho Park ),이춘우 ( Chun Woo Lee ),박수봉 ( Subong Park ) 한국어업기술학회 2017 수산해양기술연구 Vol.53 No.2

Fuel consumption in fisheries is a primary concern due to environmental effects and costs to fishermen. Much research has been carried out to reduce the fuel consumption related to fishing operations. The fuel consumption of fishing gear in fishing operation is generally related to hydrodynamic resistance on the gear. This research is to propose a low drag generated midwater trawl in terms of the gear design improvement using simulations. The results from the simulation were verified with results that mirrored the model experiments. From the results, the resistance force of the proposed gear decreased to 29% compared to that of the current gear. Furthermore, the gear performance also improved with increased gear mouth compared to the current one. Therefore, the proposed gear will be helpful to reduce the greenhouse gases from fishing operation. It will also contribute to the fishing industry by saving fuel.

주요 근해어업의 온실가스 배출량 정량적 분석

배재현 ( Jaehyun Bae ),양용수 ( Yong-su Yang ),김현영 ( Hyun-young Kim ),황보규 ( Bo-kyu Hwang ),이춘우 ( Chun-woo Lee ),박수봉 ( Subong Park ),이지훈 ( Jihoon Lee ) 한국수산해양기술학회(구 한국어업기술학회) 2019 수산해양기술연구 Vol.55 No.1

The concern on the greenhouse gas emissions is increasing globally. Especially, the greenhouse gas emission from fisheries is an important issue from the Paris Climate Change Accord in 2015. Furthermore, the Korean government has a plan to reduce the GHG emissions as 4.8% compared to the BAU in fisheries until 2020. However, the investigation on the GHG emissions from Korean fisheries rarely carried out consistently. Therefore, the quantitative analysis of GHG emissions from Korean fishery industry is necessary as a first step to find a relevant way to reduce GHG emissions from fisheries. The purpose of this research is to investigate which degree of GHG emitted from the major offshore fisheries such as offshore gillnet fishery, offshore longline fishery, offshore jigging fishery and anchovy drag net fishery. Here, we calculated the GHG emissions from the fisheries using the Life Cycle Assessment method. The system boundary and input parameters for each process level are defined for the LCA analysis. The fuel use coefficients of the fisheries are also calculated according to the fuel type. The GHG emissions from sea activities by the fisheries will be dealt with. Furthermore, the GHG emissions for the unit weight of fishes are calculated with consideration to the different consuming areas as well. The results will be helpful to understand the circumstances of GHG emissions from Korean fisheries