• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.269-275
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• 1981

The fishing hooks were tested for breaking and unbending due to plastic deformation of the material. Study of tensile test is not complicated, but has not even worked out fully enough, especially when the test specimen is subjected to plastic deformation. The fishing hook is subjected to unbending stress and the critical section is a Point which is furthest from the line of action of the forces. The dynamic force of fish during jerks depends on their speed of movement and body weight, the kinetic energy corresponding to it and also on the rlastic displacement of the rigging which absorb the energy. Six kinds of hook were tested by the dynamometer under tensile speed 290mm/min (subscript s) and 780mm/min (subscript f). According to their results, the breaking load(B: kg) can be induced with the formula $B={\alpha}wd^2+\beta$ where w(mm) is the distance between the barb base and the lower shank and d(mm) is diameter. The coefficients of the formula for the round hooks(R) and the angular hooks(A) are approximately as follows: $$R:\;\alpha_{s}=0.5,\;\beta_{s}=1.6,\;\alpha_{f}=0.4,\;\beta_{f}=1.4$$ $$A:\;\alpha_{s}=1.1,\;\beta_{s}=2.0,\;\alpha_{f}=1.0,\;\beta_{f}=0.9$$ The ratio of $B_{f}\;to\;B_{s}$ is corresponding to 0.8. The ratio of deformation(X) that is moved distance of barb base at break to the distance(H) between head base and barb base is about $50\%$. Further study should be carried out on the subject of impact and fatigue test under the same condition which is exerted force by the hooked fish.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.2
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• pp.97-103
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• 2004

This paper presents a general overview of the Korean stick-held dip net fishery for Pacific saury operated in the North Pacific Ocean since 1985. Annual catches, annual centroids distribution of fishing ground, and optimum fishing temperatures were compared between the periods before and after the new Korea-Japan bilateral fishery arrangement established in 1998. Fishing usually began in May and ended by December, during which major catches were taken in the months September~November before the bilateral fishery arrangement between Korea and Japan, whereas in August~October after the arrangement. It was observed that after the arrangement the centroids of fishing ground was shifted from the usual fishing area off the east coast of Japan to the east of South Kuril Islands, 45$^{\circ}$N and 151$^{\circ}$E. Optimum fishing temperatures appeared to be different by month ; 12.5~14.4$^{\circ}C$ in May, 12.0~14.2$^{\circ}C$ in June, 11.4~13.9$^{\circ}C$ in July, 11.4~15.9$^{\circ}C$ in August, 12.9~16.9$^{\circ}C$ in September, 12.7~17.3$^{\circ}C$ in October, 13.1~17.6$^{\circ}C$ in November, and 15.0~19.1$^{\circ}C$ in December. A total of 13 species were caught during scientific observation periods but the target species, Pacific saury, accounted for about 99.9% of the total catch. Although there was no difference in fishing days between those vessels equipped with the sonar and those without sonar, number of set, total catch, and CPUE of those with sonar were higher than those without sonar by 13%, 26%, and 12%, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.1
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• pp.1-10
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• 2002

Biomass distribution of zooplankton showed its lowest level in June in the Cheju Strait, and the highest one was noticed in November when the secondary productivity is considered high. The highest biomass of zooplankton appeared in the sea areas of Sta. 14 and 11 respectively with relation to oceanographic conditions and wet weight of biomass. The positions were the center part of the Cheju Strait, while the sea area of the South Sea of Korea and the northern coast of Cheju Island showed relatively low biomass distribution. The characteristic of the sea area where biomass was densely distributed was it was in patch shape. Meanwhile, biomass distribution was higher in the northern sea area of Cheju Island than In the coastal sea of the South Sea of Korea. It shows formation of hairtail fishing grounds is closely related to biomass distribution in the Cheju Strait. In addition, high biomass is displayed in the center part of the saddle shaped ocean, a boundary of the heterogeneous water mass as a feature of fall oceanographic condition. Good fishing grounds of a hairtail In the Cheju Strait were formed outside of the sea area that showed patch-shaped high biomass distribution.

• Journal of Navigation and Port Research
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• v.27 no.4
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• pp.431-436
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• 2003

It's about time we had to think an alternative to recover out insufficient fishery market caused by IMF locally as well as the fishery agreement on Japan and China. The Ministry of Maritime Affairs ＆ Fisheries have planning the advancing fishery information integrated system for the fishing present condition, marine resource administration and applicability consideration. The fishery information communication system is build up to the raw data ＆ process-network-content. The communication system must be small size, low cost and adapted SSB transceiver, that is using fishery shipping. In this paper We present digital data communication network to exchange information for fishery and safety between fishing ship and coast station in cheeper communication fee using SSB(single Side Band) in HF(High Frequency) band.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.4
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• pp.614-622
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• 2014

The aim of this study is to research attributes of fishermen's occupational accidents for investigating the measure of risk control on situational condition in the Korean offshore and coastal fishing vessel. Using data of fishermen's occupational accidents are from National federation of fisheries cooperatives for 2013. The results were as belows; Occupational accident occurrence rate was 29.5‰, slips & trips and struck by object and contact with gear were shown severe occurrence pattern. Occupational accident occurrence rate of offshore fisheries was 130.2‰, coastal was 16.9‰, specially the risk rates were severely high in several type of danish seine, stow net and offshore trap. Death rate by accidents was 10.6‰ and by fall into the water in occurrence pattern was 5.5‰.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.6
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• pp.1317-1323
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• 2001

The circumstance is giving the blow against fishermen with the incoming-decreasing and the difficulty of crew's supply & demand and management. In addition, the depression of the external situation like the departure of WTO system and the plan of EEZ proclaim is forcing fishery into improving their fishing condition. By this international and domestic circumstance, development of the sea water cooling apparatus for fish hold storage is demanded sincerely. First of all, we Investigated load characteristics which based on development of sea water cooling system and optimum fish hold storage. The experimental results is as follows. In creasing the speed of compressor and mass blew rate of refrigerant, the temperature of NaCl solution is low. And the load characteristics experiment on fish hold storage outlet is as fellows. As time goes by, increasing the mass flow rate of NaCl solution, temperature difference between inlet and outlet is small in a model of fish hold storage. These results provide many useful informations applicable to an actual design of sea water cooling system and optimum fish hold storage.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.42 no.4
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• pp.240-258
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• 2006

The potential of ecosystem-based fisheries management is recently recognized to be very important to improve the sustainability of fisheries resources. Under the depressed condition of many fisheries resources, this recognition has been expanded and more effort has been taken to improve this approach. Taking ecosystem concept includes the use of other tools of management in addition to fisheries regulation, such as stock and productivity enhancement, provision of physical structure, or marine protected areas. In the ecosystem-based fisheries management approach, it would require to holistically consider ecological interactions of target species with predators, competitors, and prey species, the effects of climate on fisheries ecology, the complex interactions between fishes and their habitat, and the effects of fishing on fish stocks and their ecosystem. Fisheries management based upon the understanding of these factors can prevent significant and potentially irreversible changes in marine ecosystems caused by fishing. A useful approach for analyzing tropho-dynamic interactions and mass-balance in marine ecosystems is introduced to demonstrate the complexity and usefulness of the ecosystem approach, which was applied to a small ecosystem in Korea. Korea should seriously consider to take the ecosystem-based approach to fisheries management, since most major fish stocks are currently depleted due to many reasons such as overfishing, land reclamation and coastal pollution.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.14
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• pp.323-348
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• 2000

Facing the current difficulties of fisheries industry nationally and internationally, economic cooperations between South and North Korea are needed urgently. Applying the process of economic integration to fisheries sector of separated nation, cooperation processes are divided as follows; (1) indirect and direct fisheries trade, (2) reciprocal use of fishing grounds, (3) joint venture in fisheries sector, (4) free movement of production factors and common fisheries policy. Here, fisheries trade falls under economic interchange stage. Reciprocal use of fishing ground and fisheries joint venture come in economic cooperation stage. Finally. free factor movement and common fisheries policy are related with economic integration stage. This paper investigates the schemes for fisheries cooperation between South and North Korea in preparation for a unified Korea, focusing on fisheries trade. The paper is composed of 5 chapters. Chapter 2 discusses structure and characteristics of North Korea trade, and trade situation between South and North Korea. Then, the present condition of North Korea fisheries industry and fisheries trade trend between South and North Korea are presented in chapter 3. Next, chapter 4 tackles the most common problems encountered in fisheries trade between South and North Korea, and the devices and schemes to raise fisheries trade between South and North Korea. Finally, chapter 5 summarizes and concludes the research results.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.4
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• pp.432-439
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• 2013

This study was performed to assess the current stock condition of elkhorn sculpin along the Uljin area in the East Sea of Korea. To assess the state of the stock, yield-per-recruit (YPR) and spawning biomass-perrecruit (SBPR) analyses were performed. Estimates of $F_{max}$ and $F_{0.1}$ were 2.10/year and 0.48/year, respectively, and those of $F_{35%}$ and $F_{40%}$ were 0.66/year and 0.54/year, respectively. Current fishing mortality was estimated at 0.63/year and the current age at first capture was 2.41years. $F_{40%}$ was set as the target reference point of the stock. SBPR at $F_{40%}$ and current SBPR were estimated to be 41.85g and 37.77g, respectively. Estimated FOTY which is the fishing mortality for the overfished threshold yield was 0.49/year. The ratio of SBPR/$SBPR_{MSY}$ was calculated as 0.90 and that of $F/F_{OTY}$ was 1.05. The ratio of $t_c/t_{c\;opt}$ was calculated as 1.15 and that of $F/F_{OTY}$ was 1.17. Therefore, the current stock condition of elkhorn sculpin along the Uljin area of Korea has not been overfished, however, it indicates that a light overfishing is going on this stock.

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.1
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• pp.25-32
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• 2009

The burial method has been generally used for the protection methods of submarine cable. Especially in Korea, various types of protection methods have been used according to fisheries and fishing implements. In these days, all the protection methods - burial, continuous concrete mattress, cast iron pipes, U-duct, concrete bags, rock berm, mortar bags and FCM(Flexible Concrete Mattress) are applied to the submarine cable, but these methods just focus not on the characteristics of ocean environment and the protection of environment but on the safety of submarine cable against the external damages. This research presents the protection methods of submarine cable according as the characteristics of ocean environment - external damages, depth of water, seabed condition and the protection of environment.