• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.3
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• pp.169-175
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• 2004

In order to examine the mesh selectivity and optimum mesh size of gill nets for croaker, Milichthys miiuy, the field experiments were carried out during Aug. 10 to 14, 2002 and Aug. 10 to 17, 2003 at the caostal area of Imja-Do, Shinan, Jeonnam province. The experimental fishing gears were used in two set of gill nets, which one set was consisted of 12 sheets of gill nets, and each set was connected alternatively 4 different sheets that were 129mm, 135mm, 144mm and 150mm in mesh size. The analysis of mesh selectivity curve was done by Kitahara's method. The results obtained are summerized as follows : 1. The total number of catch by the experimental fishing of gill nets for croaker was 719, and it was consisted of 526 croakers (73.1%), 168 blue crabs (23.4%), 17 harvest fishes (2.4%) and 8 other fishes (1.1%). 2. The value of maximum 1/m on the mesh selectivity curve was estimated at 6.91. 3. The value of 1/m on the 50% selection range was estimated at 5.62${\sim}$80.3, and the selection width was 2.41. 4. The optimum mesh size of gill nets for croaker was estimated 142mm, and the 50% selection range of total length of croaker was 798${\sim}$1,140mm.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.72-73
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• 2003

최근들어 인공어초의 경우 그것을 투입한 후 그 효과에 대한 문제가 많이 대두되고 있다. 인공어초는 연안어장에 인공적인 구조물을 설치하여 대상 수산물 보호, 육성하는 것을 목적으로 하는 어장 시설물이다. 인공어초를 투입한 후 그 효과를 조사하는 수단인 자망에 의한 어획실험, 장수조사, 표지방류 등이 있다. 하지만, 자망은 어초에 대한 어류의 직접적인 반응을 알기 어렵고 잠수조사는 시간의 제약성, 그리고 표지방류에 의한 방법은 재어획이 이루어져야 정보를 제공해줄 수 있다는 단점이 있다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.81-82
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• 2001

삼중자망 어업은 어떤 형태나 크기의 생물이 내유 하든지 어획이 가능하며, 또한 치자어 남획에 대한문제가 제기되어 우리나라에서는 자원 보호적인 측면에서 일부해역, 특정 어종을 제외하고 법적으로 허가가 금지된 어업이다. 그러나 특별한 어로설비를 필요로 하지 않으며, 어업기술 수준이 낮아도 조업이 가능하다는 점과 어획성능이 타 업종에 비해 높다는 이유로 연아어업자의 30％이상이 불법어구임을 알면서도 조업을 하고 있으며, 그 수는 계속적으로 증가되고 있는 추세이다. (중략)

• Journal of Korea Fishing Vessel Association
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• v.48
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• pp.24-28
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• 1991

• Journal of Korea Fishing Vessel Association
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• v.49
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• pp.21-26
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• 1992

• Journal of Korea Fishing Vessel Association
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• v.50
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• pp.41-47
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• 1992

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.41 no.2
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• pp.95-100
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• 2005

In order to improve the gill nets for croaker, Miichthys miiuy which is proper to the fishermen's income ans fisheries resource management, we had studied to the net height of present gill nets (mesh size 160mm, 50 mesh in depth), experimental gill nets-I(mesh size 150mm, 68 mesh in depth) and experimental gill nets-II(mesh size 142mm, 75 mesh in depth) in wter using the gill nets design ans analysis simulation system, and then investigated and analyzed the catch efficiency of each gill nets through the field fishing experiments. The net height of emperimental gill nets-I and experimental gill nets-II in water were estimated respectively about 1.5 times and 1.3 times higher than present gill nets which the net height is about 3.5m as the results of simulation considering the current of fishing fields. Total number of croakers which were caught by the persent gill nets was 62(body length 300~1,200mm), total catch weight was 398.7kg (mean 0.6kg/sheet). Total number of croakers which were caught by the experimental gill nets- I was 68(body length 600~1,100mm), total catch weight was 391.6kg (mean 1.2kg/sheet). Total number of croakers which were caught by the experimental gill nets-II was 28(body length 400~900mm), total catch weight was 99.2kg (mean 0.3kg/sheet).

• Korean Journal of Ichthyology
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• v.17 no.4
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• pp.279-286
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• 2005

The fish species composition and its seasonal variation of the middle East Sea of Korea were investigated from May 2004 to January 2005 using gill and set nets. A total of 59 species of fishes belonging to 31 families in 11 orders were identified in the gill and set nets; 33 species in 15 families and 6 orders were collected by the gill net, and 36 species in 26 families and 10 orders were collected by the set net. Among the fishes collected by gill net, the order Scorpaeniformes was dominant; the number of species as well as individuals was highest in summer; the biomass was highest in winter. However, in fishes collected by set net, the order Perciformes was dominant, the number of species was highest in autumn, the number of individuals was highest in spring, and the biomass was highest in winter. The fish composition of the middle East Sea differed considerably from that of the south East Sea, especially in the species composition of the order Scorpaeniformes and Pleuronectiformes. Principal component analyses for each net showed that the fish species composition depends on the kind of net used, even though the investigation was carried out in the same area and at the same time.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.2
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• pp.143-151
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• 2003

A series of fishing experiments was carried out in the waters off the east coast of Korea from January, 2002 to March, 2003, using gill nets of different mesh sizes (m = 180, 210, 240, 270, and 300 ㎜) to determine the size selectivity of gill net for male snow crab Chionoecetes opilio. The maximum carapace length (RL) of each male snow crab caught in the fishing experiment was measured. The master curve of mesh selectivity was estimated by applying the extended Kitahara's method. Two kinds of functional models, quadratic function and cubic function were used to express logarithmic selectivity curve and were fitted to the data using the method of least squares. The obtained results were summarized as follows; 1. The cubic function of asymmetry was chosen to determine the selectivity curve of gill net for male snow crab from the model deviance comparison. 2. The result of size selectivity showed that the catch number of small male crab was getting decreased according to the increase of mesh size. 3. The optimum value (RL/m) was 0.549 and the RL/m was estimated to be 0.281, 0.296, and 0.356 when the retention probability were 0.2, 0.25 and 0.5, respectively.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.05a
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• pp.45-46
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• 2002