• Title/Summary/Keyword: fishery technology

Search Result 579, Processing Time 0.022 seconds

Systemic Ground-Segment Development for the Geostationary Ocean Color Imager II, GOCI-II (정지궤도 해양관측위성 지상시스템 개발)

  • Han, Hee-Jeong;Yang, Hyun;Heo, Jae-Moo;Park, Young-Je
    • KIISE Transactions on Computing Practices
    • /
    • v.23 no.3
    • /
    • pp.171-176
    • /
    • 2017
  • Recently, several information-technology research projects such as those for high-performance computing, the cloud service, and the DevOps methodology have been advanced to develop the efficiency of satellite data-processing systems. In March 2019, the Geostationary Ocean Color Imager II (GOCI-II) will be launched for its predictive capability regarding marine disasters and the management of the fishery environment; moreover, the GOCI-II Ground Segment (G2GS) system for data acquisition/processing/storing/distribution is being designed at the Korea Ocean Satellite Center (KOSC). The G2GS is composed of the following six functional subsystems: data-acquisition subsystem (DAS), data-correction subsystem (DCS), precision-correction subsystem (PCS), ocean data-processing subsystem (ODPS), data-management subsystem (DMS), and operation and quality management subsystem (OQMS). The G2GS will enable the real-time support of the GOCI-II ocean-color data for government-related organizations and public users.

Catching Efficiency of Gill Net and Trammel Net for Ceramic Artificial Reefs Fishing Ground in the Coastal Area of Geomun-do, Korea (한국 거문도연안 세라믹어초어장에서의 홑자망과 삼중자망에 의한 어획성능)

  • Park, Seong-Wook;Kim, Dae-Kweon
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.40 no.3
    • /
    • pp.182-188
    • /
    • 2004
  • It has been, in general, known that the catching efficiency of a trammel net is better than that of a gill net because of the variability of catch species and size. In this stidy, A fishing gear test was carried out to analyze the catching efficiency of the gill net and the trammel net on the coast of Geomun-do of southern Korean waters and fish school aggregation was also investigated using a underwater video camera. CPUE of the gill net was 49.2% higher than the trammel net but fish species was 34.5% lower where there was no difference on the significance level of 5% by ANOVA test. Main catch species caught by the gill net were red seabream(Pagrus major) and triggerfish(Aluterus monoceros), skate ray(Raja Kenojei) and red seabream for the trammel net, and the average body length of red seabream was shorter than the trammel net. It was thought that the reason of higher catch in the gill net than the trammel net was a fish school which can be caught easily by gill net and the size of population was suitable for the gill net.

Abundance of Argentine shortfin squid, Illex argentinus(Castellanos) in Relation to Fluctuation of Water Temperature in the Southwestern Atlantic Ocean (수온변동에 따른 아르헨티나 짧은지느러미오징어, Illex argentinus의 풍도 변화)

  • Kim, Yeong-Seung;Kim, Doo-Nam
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.40 no.4
    • /
    • pp.282-294
    • /
    • 2004
  • Catches of Argentine shortfin squid Illex argentinus showed a sharp decrease, reaching 99,000ton in 1993 and 56,700ton in 1994, and then increased again reaching 130,300ton in 1997 from 78,600 ton in 1996. The Korean squid jigging fishery around Falkland for Illex argentinus commences usually its operation in January and lasts August and peak in catch was showed from March to May. To elucidate possible environmental effects on their abundance during the main fishing season in 1993-1994 and 1996-1997, sea surface temperatures were used as an indicator of the position and strength of the oceanographic structures in the Southwestern Atlantic Ocean. The high catch and catch per unit effort of Illex argentinus was showed when the Faliland Current was not affected in the fishing area in 1993 and 1997. But they were sharply decreased from the middle of April 1994 and the late of April 1996 when the Faliland Current directly affects the fishing ground.

A selective effect of grid and window net in the shrimp beam trawl fishery (새우조망 어업에서 그리드와 윈도우 네트의 선택효과)

  • JANG, Choong-Sik;CHO, Youn-Hyoung;AN, Young-Su
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.51 no.3
    • /
    • pp.375-386
    • /
    • 2015
  • The study aims at a selective effect of the Grid and Window net in the shrimp beam trawl. The experimental trawling of the Proto type, Grid type and Grid and Window net type was performed in a sea area of Geo-je and Tong-yeong from Mar, 2006 to Apr, 2010. The obtained results are as follows; Catch per unit area (Number) of the Proto type net and Grid type net were $0.18/m^2$, $0.23/m^2$, respectively. The Grid type demonstrated 2.4% lower bycatch rate than the proto type (6.6% vs 4.2%, respectively). In addition, in terms of total weight, the bycatch rate of Grid type was 7.6% lower than the proto type (50.2% vs 42.6%, respectively). In the comparison of shrimp catch, the Proto type demonstrated better haul outcome ($0.02case/m^2$) than the Grid & Window type ($0.02case/m^2$). The Grid & Window net type demonstrated 16.4% lower bycatch rate than the Proto type (32.2% vs 48.6%, respectively). In addition, in terms of total weight, the bycatch rate of Grid & Window net type was 8.3% lower than the Proto type (85.9% vs 94.2% respectively).

Feeding habits of the Pacific bluefin tuna, Thunnus orientalis in the southern sea of Korea (한국 남해안에 출현하는 태평양참다랑어 Pacific bluefin tuna, Thunnus orientalis의 식성)

  • YOON, Sang Chul;YOO, Joon Taek;LEE, Sung Il;KIM, Zang Geun;CHOI, Kwang Ho
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.51 no.4
    • /
    • pp.553-560
    • /
    • 2015
  • The feeding habits of the Pacific bluefin tuna, Thunnus orientalis were examined based on the stomach contents of 330 specimens caught by offshore large purse seine fishery in the southern sea of Korea, 2011. The size of Pacific bluefin tuna used in this study ranged from 34.1 to 67.3 cm in fork length (FL). The percentage of empty stomachs was 41.8%. The main prey items were Pisces and Cephalopoda based on percentage IRI (index of relative importance). The main fish preys were Trachurus japonicus, Bregmaceros japonicus, Engraulis japonicus, and Cephalopoda were Todarodes pacificus, Loligo edulis, Watasenia scintillans. T. orientalis showed ontogenetic change in diet composition. Although Pisces dominated the diet of all length classes the portion of Cephalopoda was relatively higher in size between 40 and 50 cm other than length classes. In terms of seasonal variation in feeding habits, Pisces was the main prey group in all seasons, but Cephalopoda was also frequently consumed during spring and autumn based on %IRI.

An acoustic and trawl pilot survey using a small vessel in Jinhae bay of the South Sea of South Korea (진해만에서 수행된 소형선박을 이용한 음향과 트롤 시험조사)

  • PARK, Junseong;LEE, Jeong-hoon;HWANG, Kangseok;CHA, Hyung Kee;PARK, Junsu;KANG, Myounghee
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.52 no.1
    • /
    • pp.24-35
    • /
    • 2016
  • An acoustic and trawl pilot survey using a small vessel was conducted in Jinhae bay of the South Sea of South Korea on April 13~14, May 11~13 and June 8~10, 2015. During the survey, acoustic data was collected and bottom trawls were conducted at the same time. First, various noises were eliminated by using the Park method based on the Wang method (Wang et al., 2015; Park et al., 2015), the species compositions and catch rate from each bottom trawl were observed, and spatial distribution of fishery resources in the water column and their nautical area scattering coefficient (NASC) were investigated through acoustic data. During the entire survey period, 12 orders, 33 families and 41 species were caught. The most caught species in April, May and June were Okamejei kenojei, Zoarces gilli and Pholis nebulosa, respectively. Fish schools were observed near the line of net mouth height in April. Numerous weak scatters were presented on the echograms in May and June. Many fish schools appeared in between the water surface and 20 m deep in May. The NASC value from entire water columns was the lowest in April ($35.9m^2/n{\cdot}mile^2$) and highest in June ($1541.3m^2/n{\cdot}mile^2$).

Species composition and distribution property of dredge fishery in Yeongil Bay, Korea (영일만 형망어업 어획물의 종조성 및 분포 특성)

  • HONG, Sung-Eic;BAE, Jae-Hyun;PARK, Chang-Du;PARK, Jong-Myung;YOON, Byung-Sun;AN, Heui-Chun
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.52 no.1
    • /
    • pp.48-55
    • /
    • 2016
  • The species composition and distribution of catches by dredge gear in the Yeongil Bay, Korea were investigated on a seasonal basis from February to November, 2015. Total catches consisted of 44 species and 35 families. They were 13 species of fish, 10 species of crustacea, 5 species of echinodermata, 5 species of gastropoda, 4 species of cephalopoda and 3 species of bivalvia. Major catch species was shellfish and had seasonal variations in catch. In spring and winter, the catch of ark shell (Scapharca broughtonii) was increased. Adversely, the catch of admas venus clam (Callithaca adamsi) increased in sunmmer and autumn. Species diversity indices was high as the value of 1.99 in spring, and low to the value of 0.34 in summer. In addition, multi dimentional scaling (MDS) indices also was high in spring as the value of 1.99. In summer, the index was low as the value of 0.34. Similarity analysis based on species data was transformed by fourth root. With the result of cluster analysis and MDS analysis, species was divided into two groups. The first group as Group A consists of winter and spring species and another was Group B made of species in summer and winter.

Analysis on the national catch, CPUE and monthly fishing grounds of walleye pollock, Theragra chalcogramma by the trawl fishery in the high seas of the Bering Sea (베링공해 명태 트롤어업의 국가별 어획량, CPUE 및 월별 어장)

  • JO, Hyun-Su
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.52 no.2
    • /
    • pp.141-148
    • /
    • 2016
  • Annual and monthly pollock catches, CPUE and fishing grounds in the high seas of Bering Sea between 1984 and 1992 were analyzed for centroid distribution and bivariate ellipses of trawlers of South Korea, Japan, Poland and China. The catch amount differed by country as 56.1%, 21.7%, 20.4% and 1.8% were caught by Japan, Korea, Poland and China respectively. Japan recorded the highest mean CPUE at 5.7 ton/hour while it was 4.3 ton/hour for Poland, 3.9 ton/hour for Korea and 2.4 ton/hour for China. Cumulative catch varied by month, with the minimum of 137,000 ton in March and the maximum of 848,000 ton in December. Monthly mean of CPUE was the lowest in February (2.0 ton/hour) and the highest in November (6.3 ton/hour). The centroid distribution of monthly fishing ground was located at a southern spot ($56^{\circ}$ 05'N, $178^{\circ}$ 55'E) in January, and it moved anti-clockwise toward $56^{\circ}$ 37'N, $178^{\circ}$ 24'E in December. Fishing grounds were scattered more by the east-west direction than by the south-north direction. The fishing grounds were similar for Korean, Japanese and Polish trawlers, but Chinese trawlers that fished only from July to December showed distinctively different fishing grounds from the others.

Evaluating Quantitative Expansion Goals of the National Protected Areas Integrated System (국가 보호지역 통합 시스템의 양적 확대 목표에 대한 평가)

  • Hong, Jin-Pyo
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.21 no.3
    • /
    • pp.57-65
    • /
    • 2018
  • The study is conducted to establish the National Protected Areas Integrated System(NPAIS) which includes National Protected Areas(NPAs) and other conservation measures in terms of effective ways for biodiversity conservation. Additionally, it is carried out to evaluate progress toward quantitative expansion goals in Aichi biodiversity Target 11. The NPAIS consists of NPAs and other effective area-based conservation measures(OECMs). There are two different types of OECMs. OECMs type I, including water-source protection Areas(WPA), riparian zones(RZ), fishery-resource protection zones (FPZ), and urban natural park zones(UNPZ), is a potential protected area which is recommended to be incorporated into the NPAs for effective management. OECMs type II means development restriction zones(DRZ), natural recreation forests(NRF), and buffer zones for Korea national arboretum(BKNA). As a result of evaluating the quantitative expansion goals of the NPAIS, terrestrial and inland water protected areas exceed 17% of the quantitative goal in Aichi biodiversity Target 11. The larger the area of individual OECMs and the lower the degree of overlap with NPAs, the higher the contribution of them to the terrestrial and inland water protected areas. DRZ contributes to enlarge more than 3% of quantitative expansion. And RZ and NRF contribute more than 1%. The marine protected areas are expanded by $1,425km^2$ through FPZ, but the expanded area is very small as comparing with the total marine area. It adds only 0.321% to the quantitative expansion. The rest of OECMs also has very poor quantitative expansion contributions in the marine area. Consequently, the NPAIS is effective for quantitative expansion of land areas, but not for marine areas.

Development of fishing gear and fishery operation system for the croaker drift gill net 2. Performance tests of labor saving type model net hauler (조기유자망 어구의 개량 및 생력화 조업시스템 개발 2. 생력형 모형 양망기의 성능 시험)

  • Kim, Suk-Jong;Koo, Myung-Sung
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.41 no.3
    • /
    • pp.199-206
    • /
    • 2005
  • As the basic study about improvement of yellow croaker drift gill net fishing implement and development of the fishing system, this study drew problem after synthetically analyzing hauling system of yellow croaker drift gill net used in the coast of Chuja Island and tested several characters and analyzed in hauling process with 5 step net hauler model for improving the problem. The analysis results are as follows. When the angle between axises of drum centers was small, it showed the tendency that hauling time was fast. Hauling time was faster when drum was 5 step rather than 3 step. When drum was 5 step, slippery phenomenon was small and hauling was stable. Tension was larger when drum was 5 step rather than 3 step. When drum was 5 step, the range of change of the maximum and minimum value was small and hauling was stable. When drum was 3 step, there was following formula between hauling time ($Ht_3$) and angle between axises of drum centers ($A_g$) $Ht_3$ : ($7.15Hs^{-0.81}$) $A_g^{-0.81}$, when drum was 5 step there was following formula.$Ht_5$ : ($6.45Hs^{-0.75}$) $A_g0.10$, here, Hs is hauling speed. When drum was 3 step and hauling speed was 28cm/sec, tension was $T=0.08A_8^3-1.60A_g^3-0.49A_g+369.56(r=0.99)$, when drum was 5 step, tension was, $T=-0.01A_g^3+1.96A_g^2-34.05A_g+414.58$ (r-0.99), here, T was tension(g).