• Title/Summary/Keyword: catch rate

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Stock Assessment and Optimal Catch of Blackfin Flounder Glyptocephalus stelleri in the East Sea, Korea (한국 동해안 기름가자미(Glyptocephalus stelleri)의 자원평가 및 적정어획량 추정)

  • Sohn, Myoung Ho;Yang, Jae Hyeong;Park, Jeong-Ho;Lee, Haewon;Choi, Young Min;Lee, Jae Bong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.5
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    • pp.598-606
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    • 2013
  • The blackfin flounder Glyptocephalus stelleri is a commercially important species in the East Sea of Korea, but its catches and biomass have decreased gradually in recent years. This study estimated the optimal catch (acceptable biological catch, ABC) for the effective management of this species by estimating population ecology parameters and the stock biomass of blackfin flounder in the East Sea of Korea. The estimated instantaneous coefficient of total mortality (Z) of blackfin flounder was 1.0542/year, the survival rate (S) was 0.3485, and the instantaneous coefficient of natural mortality (M) was 0.3637/year. From the values of S and M, the instantaneous coefficient of fishing mortality (F) was calculated to be 0.6905/year. The age at first capture was 1.304 years, and the total length was 11.5 cm at that time. On the basis of these parameters, the annual biomass was estimated by a biomass-based cohort analysis using annual catch data in weight by year for 1991-2012 in the East Sea of Korea. The annual biomass peaked in 1997 at about 12,800 mt and then subsequently declined continuously to a level of 10,500 mt in 2004 and to 9,800 mt in 2011 and 2012. The maximum sustainable yield and $F_{0.1}$ were estimated as 3,547 mt and 0.3595/year, respectively. Using these estimations, the ABC was estimated to be 3,571 mt in tier 5, 3,397 mt in tier 4, and 2,622 mt in tier 3.

A Study on the Marketing System Construction and Merchandising of Tongyoung Marine Ranching (통영바다목장의 유통체제 구축과 상품화계획에 관한 연구)

  • 강종호;류정곤
    • The Journal of Fisheries Business Administration
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    • v.34 no.2
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    • pp.91-107
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    • 2003
  • Distribution of fish products from Tongyoung Marine ranching can be classified by three routes such as street-stall, live fish transportation vehicles, and wholesale markets neighboring unloading ports. These methods of distribution, however, have been restricted by limited distribution right, difficulties to differentiate fish prices from other surfaces, simple marketing channels. The ratio of cultured live fish circulated in market is increasing while naturally caught live fish is decreasing and the fresh fish shows a little of increasing rate. Consumers purchasing routes mainly depend on the live fish transportation merchants. For fresh fish traditional market plays an important role in trade. Convenience for consumers and quality of products are main factors in making decision of purchases. Bargaining power, however, belongs to the live fish transportation merchants. The demand of special markets for live fish was very strong, and the convenience and quality are relatively important required factors. Catch from Tongyoung Marine ranching has very good reputation as the possibility of being a good brand. Expecting possibility of quality differentiation was higher than price differentiation specially. The possible conclusion of a contract of a supply was suspicious however. Preliminary quality evaluation revealed that the catch is better than the cultured but worse than naturally grown fish. A merchandising is to be in a better position in the formation of prices by giving $\ulcorner$brand image$\lrcorner$ to potential consumers. The target markets are retail stores such as restaurants for raw fish and final consumers. The staple markets are retail stores. Possible items of products are live fish, fresh fish for cook, and fresh fish for raw fish. It is necessary for the catch to be informed as new functional products that have been improved in safety and quality, since the product positioning is similar but not well known to consumers. To secure a brand it is required to register a trademark, eco-label product design or packing, use real name in tranction, introduce recall system, and put label. Price higher than naturally grown live fish should be targeted. Establishing broad distribution channel, wholesale market, franchise are required. To secure enough catch and control shipment of products facilities of containing live fish are necessary. Instead of dealing with live fish only, it would be better to. sell fresh fish and live fish simultaneous. Strategically promotion focuses on advertisement of Marin ranching at first and then focuses on the catch from the marine ranching.

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Development of a Trawl Escapement Net using net material (망지를 이용한 트롤 탈출장치 개발)

  • Cho, Sam-Kwang;Shin, Jong-Keun;Cha, Bong-Jin;Yang, Yong-Su
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.44 no.3
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    • pp.165-173
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    • 2008
  • Sea experiment for this study was carried out to develop a Trawl Escapement Net(TEN) using net material to improve the survival rate of undersized fishes that escaped from trawls in the Korean southern sea in May and November, 2005. Three kinds of Trawl Escapement Net(TEN) were examined to increase the escapement rate for fishes escaped from the TEN, and total catches in the codend and cover-net were investigated. The main catch species in the experimental fishing trials using a V shape TEN(A type) in May were Korean pomfret(Pampus echinogaster), slimy(Leiognathus nuchalis), gizzard shad(Konosirus punctatus), white croaker(Pennahia argentata) and smelt(Sillago sihama). In the experimental fishing trials using a V shape TEN with a protector for undersized fishes(B type) and a panel shape TEN with a protector(C type) in November, the main catch species were horse mackerel(Trachurus japonicus), sea pike (Sphyraena japonica), large-head hairtail(Trichiurus lepturus), kammal thryssa(Thryssa kammalensis), white croaker(Pennahia argentata), butterfish(Psenopsis anomala) and red gurnard(Lepidotrigla microptera). Most of large-sized fish species like Korean pomfret and Spanish mackerel could not escape through the TEN in the B type and C type. Catches of horse mackerel were highest in the experimental fishing of November and escapement rates for most fish species including horse mackerel were higher in the C type compared with B type.

Fishing Characteristics of the Mesh Size and Flapper Connecting Line for a Rockfish Sebastes inermis Trap (볼락(Sebastes inermis) 통발의 망목크기와 혀그물 연결줄에 따른 어획 특성)

  • Heo, Gyeom;Cho, Sam-Kwang;Koo, Myung-Sung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.55 no.5
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    • pp.751-757
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    • 2022
  • To develop a trap to prevent the catch of juvenile rockfish Sebastes inermis and bycatch, we compared the fishing characteristics of four traps with different mesh sizes (35 mm and 50 mm) and flapper connecting lines (FCL) (3 lines and 4 lines).The number of rockfish caught in trap 1 (35 mm, 4 FCL) was 200, and juvenile rockfish (15 cm or less) accounted for 49.0%. The number of rockfish caught in trap 2 (35 mm, 3 FCL) was 185, and juvenile rockfish accounted for 58.9%. The number of rockfish caught in trap 3 (50 mm, 4 FCL) was 82, and juvenile rockfish accounted for 4.9%. The number of rockfish caught in trap 4 (50 mm, 3 FCL) was 68, and juvenile rockfish accounted for 22.1%. The total catch (bycatch rate) in trap 1, trap 2, trap 3 and trap 4 was 565 (64.6%), 637(71.0%), 260 (68.5%) and 276 (75.4%), respectively. The catch per unit effort (CPUE) for juvenile rockfish in trap 1, trap 2, trap 3 and trap 4 was 0.8, 0.9, 0.0, and 0.1 individuals/trap, respectively. The CPUE of bycatch in trap 1, trap 2, trap 3 and trap 4 was 2.9, 3.6, 1.4 and 1.7 individuals/trap, respectively.

Development of Panel Part in Flight Simulator based on PC (PC 기반의 항공기 시뮬레이터 패널부분 개발)

  • 이준우;채상원;이칠기
    • Journal of the Korea Society for Simulation
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    • v.10 no.4
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    • pp.31-40
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    • 2001
  • The flight simulator should be made like a actual flight. For the scene of sight, instrument should show the condition of flight and the pilot should catch the altitude, speed, pose and rate of lift of the airplane. This paper describes visual training program of driving airplane in practice. It is for beginners using joystick in PC, implements airplane physical equations. Flight simulator in it implements airplane panel parts in order to make simple modeling, And it uses rendering technology to implement vision parts of panel. It uses double buffering In make it faster and more efficient..

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3D Flight Simulator for Education of Flying Tactics (교육 훈련용 3차원 항공기 시뮬레이터의 구현)

  • 최성윤;채상원;한영신;이칠기
    • Journal of the Korea Society for Simulation
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    • v.12 no.3
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    • pp.1-11
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    • 2003
  • The flight simulator should be made like a actual flight. For the scene of sight, instrument should show the condition of flight and the pilot should catch the altitude, speed, pose and rate of lift of the airplane. The paper describes 3D flight visual training program of driving airplane in practice. It is for beginners using joystick in PC, implements airplane physical equations. And it uses rendering technology to implement vision parts of flying object.

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3D Flight Simulator for Education of Flying Tactics (교육 훈련용 3차원 항공기 시뮬레이터의 구현)

  • 최성윤;채상원;한영신;이칠기
    • Proceedings of the Korea Society for Simulation Conference
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    • 2003.06a
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    • pp.37-42
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    • 2003
  • The flight simulator should be made like a actual flight. For the scene of sight, instrument should show the condition of flight and the pilot should catch the altitude, speed, pose and rate of lift of the airplane. The paper describes 3D flight visual training program of driving airplane in practice. It is for beginners using joystick in PC, implements airplane physical equations. And it uses rendering technology to implement vision parts of flying object.

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Growth and Development in Infants and Children Born Prematurely Who were Registered at the Public Health Center in G City (G시 보건소에 등록된 미숙아의 영유아기 성장과 발달 상태)

  • Ju, Hyeon-Ok
    • Child Health Nursing Research
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    • v.14 no.1
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    • pp.44-52
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    • 2008
  • Purpose: The purpose of this study was to evaluate and compared the growth and development of premature and full-term infants during the 2 years after birth. Method: The participants were 102 infants, 51 each for premature infants, and for healthy full-term infants. Participants in the premature group accounted for 17.5% of all premature infants who were registered at the public health center in G city. Developmental status was evaluated using the Korean Denver II. Results: The catch-up growth of the premature was 100% in weight and in height. Suspicious developmental delay according to the Korean Denver II was 3.9% in normal infants and 31.2% in premature infants. Factors related to the suspicious developmental delay in premature infants were their age and health state at birth. The rate of suspicious developmental delay was higher in infants over 6 months and infants unhealthy at birth. Conclusion: A premature follow-up program, which includes nutrition education to achieve catch-up growth and to prevention obesity, along with continuous developmental screening test for infants and children born prematurely is recommended. Provision for home visits and telephone counseling for premature infants and their families who do not to use the public health center should also be included.

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Bycatch Reduction by Experimental Shaking Codend Attached with Canvas in a Bottom Trawl

  • Kim, Yonghae
    • Fisheries and Aquatic Sciences
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    • v.18 no.3
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    • pp.325-332
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    • 2015
  • An active stimulating method for juvenile fishes to drive escaping from mesh of the codend was examined by shaking canvas in the bottom trawl followed by shrimp beam trawl. Field fishing trials by a bottom trawl were carried out between the Geomoondo and Jejudo in west of South sea, Korea by conver-net methods to examine the effect on the reduction of juvenile fish as a discard catch by generating a shaking movement of the codend using two pieces of asymmetrical semi-circular canvas. The mean period of the shaking motion with the round canvas was 10-15 s, and the range of amplitude as a vertical depth change was up to 0.4-0.6 m when towing speed 3.4-4.3 k't as estimated by peak event analysis. The escape rate of juvenile fish in conver-net by total juvenile bycatch (codend and cover-net) in 14 trials increased from 20% in a steady codend to 34% using a shaking codend in the bottom trawl, while the marketing catch or total bycatch was similar between steady and shaking cod ends. There was no difference in the body size of the fish and species composition between the steady and shaking cod ends. Above results demonstrate a new method for bycatch reduction actually up to 18% using an active stimulating device, although further experiments are needed to increase an effective shaking motion of the codend in amplitude and period for more bycatch reduction.

Quality Comparison of Commercial Boiled-dried Anchovies by Different Catch Methods

  • Kim Jin-Soo;Heu Min-Soo
    • Fisheries and Aquatic Sciences
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    • v.5 no.3
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    • pp.245-250
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    • 2002
  • This study was conducted to compare the quality among commercial boiled-dried anchovies caught by different methods. Regardless of catch methods, the moisture, salinity and acid-insoluble ash contents of commercial boiled-dried anchovies ranged from $23.2-25.2\%,\;6.8-7.4\%$. and $0.32-0.46\%$, respectively. By sensory evaluation, these anchovies were less than $5\%$ in break-age, whitish or yellowish in color and had a foul smell. Judging from the above results and Korean Standards (KS) for foods, these anchovies were classified into special grade. There was no difference in total amino acid content. While, in a major mineral content, boiled-dried anchovy caught by set net (BA-SN) was the highest, and those caught by lift net (BA-LN) and tow net (BA-TN) followed in order. The lipid oxidation progressed at the slowest rate in the BA-SN, and then no difference in the lipid oxidation was found between the BA-LN and BA-TN. Judging from the results of chemical analysis and sensory evaluation, the BA-TN was the worst quality among the commercial boiled-dried anchovies. No difference in quality was found between the BA-LN and the BA-SN.