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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of the Korean society of Fisheries Technology
Journal Basic Information
Journal DOI :
The Korean Society of Fisheries Technology
Editor in Chief :
Volume & Issues
Volume 44, Issue 4 - Nov 2008
Volume 44, Issue 3 - Aug 2008
Volume 44, Issue 2 - May 2008
Volume 44, Issue 1 - Feb 2008
Selecting the target year
Comparison of fishing efficiency on octopus traps to reduce bycatch in the East Sea
Shin, Jong-Keun ; Cha, Bong-Jin ; Park, Hae-Hoon ; Cho, Sam-Kwang ; Kim, Hyun-Young ; Jeong, Eui-Cheol ; Kim, Yeong-Hye ; Kim, Bu-Young ;
Journal of the Korean society of Fisheries Technology , volume 44, issue 1, 2008, Pages 1~9
DOI : 10.3796/KSFT.2008.44.1.001
This study aims to reduce the bycatch of young fishes and other species in the octopus(Octopus vulagris, Octopus dolfleini) trap fishery on the East Sea, Korea. We carried out field experiments and tank experiments to verify the fishing efficiency and bycatch with the different 8 types of trap. 4 of them had mesh size 20, 35, 55 respectively and 75mm, 2 of them with escape ring of diameter 30mm and 50mm and 2 of them with escape device. The gap was 20 and 40mm respectively. The mesh sizes of the traps with ring and frame were 20mm. The traps with mesh size 20 and 35mm were not reasonable because it could fish under 300g octopus as bycatch which is not permitted by the Korean fisheries regulations. The catch number of octopus over 300g by traps with escape ring of diameter 30mm was 53. The catch of trap with mesh size 20mm was 54. The catch of trap with mesh size 35mm was 53. There is no significant difference among them. The catch number of octopus over 500g that is fishermen's favorite one was 46 in the trap with escap ring. The diameter of was 30 mm and the catch of trap with mesh size 20mm was more 3 catch and the catch of trap with mesh size 35mm had 6 more catch. Fishermen wanted to catch over 500g octopus because the octopuses had commercial value. The traps with escape ring can be replaceable with he traps with mesh size 20 or 35mm because the trap is suitable to conserve the octopus resources and keep the fishermen's fishing substantiality.
Simulation of the virtual mackerel behavior to the trawl gear
Lee, Gun-Ho ; Lee, Chun-Woo ; Kim, Young-Bong ; He, Pingguo ; Choe, Moo-Youl ;
Journal of the Korean society of Fisheries Technology , volume 44, issue 1, 2008, Pages 10~19
DOI : 10.3796/KSFT.2008.44.1.010
This paper focuses on the mackerel's visual ability and swimming capability, and aims to describe the behavior in capture and escape process by trawl. The visual sensory systems and reaction behavior based locomotory capability were analyzed and simulated. The ability of fish to see an object depends on the light intensity and the contrast and size of the object. Swimming endurance of the fish is dependent on the swimming speed and the size of the fish. Swimming speeds of the fish are simulated 3 types of the burst speed, the prolonged speed and the sustained speed according to the time they can maintain to swim. The herding and avoiding is typical reaction of the fish to the stimuli of trawl gear in the capture process. These basic behavior patterns of the virtual mackerel to the gear are simulated. This simulation will be helpful to understand the fishing processes and make high selectivity of fishing.
Evaluation of biodegradability according to bait type for crab pots
Jeong, Byung-Gon ; Chang, Ho-Young ; Koo, Jae-Geun ;
Journal of the Korean society of Fisheries Technology , volume 44, issue 1, 2008, Pages 20~30
DOI : 10.3796/KSFT.2008.44.1.020
In order to evaluate the biodegradability of bait used in the pot for swimming crab, water tank experiments were conducted. Mackerel is the most commonly used natural form of bait to catch the swimming crabs, and therefore was used in this experiment for the biodegradability according to the manufacturing process of the bait. From the biodegradability test on chemical oxygen demand(COD), total nitrogen(T - N), total phosphorus(T - P), ammoniac nitrogen, nitrite nitrogen and nitrate nitrogen per unit weight of the bait based on the production rate and the accumulated amount of pollutants, it was concluded that the smaller the size of the mackerel pieces, the higher the production rate and accumulated amount of organic matter and nutrients which was unfavorable to water pollution. The amount of pollutants released from the intestine of the tuna was similar with that from the whole mackerel. For the operation period of 111 days, the accumulated concentrations of tested pollutants from the tuna which were 67.3 mgCOD/g d, 86.4 mgT N/g d, 3.1 mgT - P/g d, were almost half comparing with those from the mackerel which were 65.7 - 94.4 mgCOD/g d, 83.8 - 109.4 mgT - N/g d, 3.1 - 5.2 mgT - P/g d. The amount of pollutants released from the intestine of the tuna was slightly less than that from the mackerel that was cut into 8 pieces. but more than that from the mackerel which was not cut into pieces. Therefore, it can be concluded that the key factor in determining water pollution potential is not the kind of bait, but the processing or preparation method used.
Trial manufacture of the underwater sound transmission system to measure the appearance frequency of cetacean at the fixed point
Shin, Hyeong-Il ; Seo, Du-Ok ; Kim, Seong-Ho ; Kim, Byung-Yob ; Lee, Yoo-Won ;
Journal of the Korean society of Fisheries Technology , volume 44, issue 1, 2008, Pages 31~36
DOI : 10.3796/KSFT.2008.44.1.031
The underwater sound transmission system(USTS) was experimentally made to monitor the cetacean's appearance by telemetry, and then its system was tested to evaluate its performance from July to October, 2007 at the Kimnyeong berth and the dolphin's breeding ground of Pacific Land in Jeju island, respectively. The results showed that the sweep sound in the trial experiment and the whistle sound of bottlenose dolphin(Tursiops truncatus) were favorably received by telemetry. Therefore, we could confirm the USTS is able to monitor the cetacean's appearance in real time without direct observation at sea within effective range of code division multiple access(CDMA) communication method.
Acoustic target strength measurements on immobile riverine shrimp, oriental river prawn(Macrobrachium koreana), in freshwater
Hwang, Bo-Kyu ; Shin, Hyeon-Ok ; Cho, Sung-Ho ; Lee, Dae-Jae ; Kang, Don-Hyug ;
Journal of the Korean society of Fisheries Technology , volume 44, issue 1, 2008, Pages 37~45
DOI : 10.3796/KSFT.2008.44.1.037
Assessment and management of fisheries abundance in fresh water like a river or a lake is very important to maintain fisheries itself as well as tourist industry even if their scale is not much large. The species for catch in fresh water are mainly a mandarin fish, a carp, an eel, and others. Because oriental river prawn is a main prey of these species and the change in its abundance is directly related to their abundance change in fresh water, information on the abundance and distribution of the species are necessary. Hydroacoustic survey is known to one of the efficient method among several methodology. Information on acoustic target strength is key parameter to estimate abundance for acoustic survey. In this study, measurements on oriental river prawn, Macrobrachium koreana, were conducted for two high frequencies(200kHz and 420kHz) with tilt angle using automatic rotating system. The results of acoustic target strength obtained from the experiment were compared with those of acoustic scattering model, Distorted Wave Born Approximation(DWBA) model. For 200kHz, the result of acoustic target strength experiments was expressed in terms of the averaged target strength dependence on the body langth(BL, cm) as a following relationship; <
> = 45.9log(BL) - 107.4. These results provide basic information for studying acoustic target strength and conducting acoustic survey of oriental river prawn.
Hydrodynamics of submersible aquaculture cage system using numerical model
Kim, Tae-Ho ; Fredriksson, David W. ; Decew, Judson ;
Journal of the Korean society of Fisheries Technology , volume 44, issue 1, 2008, Pages 46~56
DOI : 10.3796/KSFT.2008.44.1.046
A numerical model analysis was performed to analyze the motion and mooring tension response of submersible fish cage systems in irregular waves and currents. Two systems were examined: a submersible cage mooring with a single, high tension mooring and the same system, but with an additional three point mooring. Using a Morison equation type model, simulations of the systems were conducted with the cage at the surface and submerged. Irregular waves(JONSWAP spectrum) with and without a co-linear current with a magnitude of 0.5m/s were simulated into the model as input parameters. Surge, heave and pitch dynamic calculations were made, along with tension responses in the mooring lines. Results were analyzed in both the time and frequency domains and linear transfer functions were calculated.
Development of intelligent agent system for automated ship CAE modelling by non-deterministic optimized methods
Bae, Dong-Myung ; Kim, Hag-Soo ; Shin, Chang-Hyuk ; Wang, Qing ;
Journal of the Korean society of Fisheries Technology , volume 44, issue 1, 2008, Pages 57~67
DOI : 10.3796/KSFT.2008.44.1.057
Recently, Korean shipbuilding industry is keeping up the position of world wide No. 1 in world shipbuilding market share. It is caused by endless efforts to develope new technologies and methods and fast development of IT technologies in Korea, to raise up its productivities and efficiency in shipbuilding industry with many kinds of optimizing methods including genetic algorithm or artificial life algorithm... etc. In this paper, we have suggested the artificial life algorithm with relay search micro genetic algorithm. and we have improved a defect of simple genetic algorithm for its slow convergence speed and added a variety of solution candidates with applying relay search simple genetic algorithm. Finally, we have developed intelligent agent system for ship CAE modeling. We have tried to offer some conveniences a ship engineer for repeated ship CAE modeling by changing ship design repeatedly and to increase its accuracy of a ship model with it.
Hull form development of the high speed small fishing boat
Lee, Kwi-Joo ; Joa, Soon-Won ;
Journal of the Korean society of Fisheries Technology , volume 44, issue 1, 2008, Pages 68~74
DOI : 10.3796/KSFT.2008.44.1.068
This study is concerned with the development of the basic planing hull form of small fishing boat in 25 knots high speed. A series of model test to determine the optimum performance hull form of actual fishing boat with 10 gross tonnage was carried out for 5 models made available planing hull form in the circulation water channel. Model test was performed with the resistance test to study the hydrodynamic characteristics of model ships and the sinkage and trim measurement to investigate the stability of model ships and also the wave pattern observation to analyze the effectiveness of model ships. As the result, the planing hull form of P-4 with deep V type bow can be derived as the best hull form with good performance especially in ship's resistance efficiency showing less residual resistance and sinkage and trim and the spray effect, etc..
The disposal process for scrapped FRP fishing vessels
Song, Jung-Hun ;
Journal of the Korean society of Fisheries Technology , volume 44, issue 1, 2008, Pages 75~80
DOI : 10.3796/KSFT.2008.44.1.075
A scrapped fiber-reinforced plastic(FRP) fishing vessel causes many environmental problems, because technology development for recycling FRP vessel has not been adequately addressed. FRP is a main material for constructing a small coastal fishing vessel that is an object of reduction policy. Therefore, the FRP wastes derived a scrapped fishing vessel are increasing. In this study, I investigated an effective disposal process for FRP through the analysis of the actual conditions of scrapped FRP fishing vessel. The treatment processes of scrapped FRP fishing vessel are carried out with oil-removing, dismantling, intermediated processing(crushing), and then reclaiming follows burning in the final processing in Korea. However, in Japan, several recycling methods have been developed, for example, the incineration including thermal recovery, the use of cement-reclamation, and the use of asphalt concrete aggregate, because the method of reclaiming after incinerating which is generally used in Korea produces a toxic by-product such as dioxin.