• 제목/요약/키워드: By-catch

검색결과 995건 처리시간 0.026초

여수연안 낙지주낙 어장의 해황과 어획 변동에 관한 연구(2) (Influence of Sea Condition on Catch Fluctuation of Long Line for Common Octopus, Octopus Variddilis, in the Coastal Waters of Yosu (2))

  • 정정민;김동수
    • 수산해양기술연구
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    • 제37권4호
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    • pp.326-330
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    • 2001
  • 낙지주낙 어장의 환경요인이 어획량에 미치는 영향을 조사하기 위하여 1997년 1월부터 7월까지 여수연안에서 풍향, 풍속, 물때별 및 조업 시각대별로 어획량을 각각 사하고 이들을 서로 비교 분석한 결과를 요약하면 다음과 같다. 1) 풍향별 어획량은 남동풍일 때 가장 많았고 북서풍일 때 가장 적었으며, 풍속별 어획량은 2일 때 가장 많았고 그보다 커질 경우는 감소하였다. 2) 물때별 단위 노력당 어획량은 15물에서 가장 많고 4물에서 가장 적으며, 조류가 차차 약해지는 11∼14물 사이의 어획량이 조류가 차차 강해지는 1∼4물 사이의 어획량보다 많았다. 3) 썰물과 밀물 때의 어획량은 간조에서 만조로 바뀐 후 1시간 동안의 구간, 즉 간조에서 물이 들기 시작한지 1시간 동안에 어획량이 가장 많았고, 썰물 시각대 보다는 밀물 시각대에 어획량이 비교적 많은 경향이었다.

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참조기 유자망의 설 높이에 따른 어획특성 (Fishing characteristics of small yellow croaker drift gill net by net height)

  • 오택윤;조영복;서영일;김병엽;이창헌
    • 수산해양기술연구
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    • 제50권3호
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    • pp.368-377
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    • 2014
  • Small yellow croaker is one of the important stocks in Korean waters. In this study, we conducted sea trials to estimate optimum height of a drift gill net for effective fishing of small yellow croaker. In the trial using existing net which has 9.2m in height, there was 22 species (1,180 fishes, 99.9kg) caught. The catch (in individuals) of small yellow croaker, especially larger fishes (over 22cm in FL), was higher as part of net height is higher, while the number of species bycaught and the catch of those species were higher as part of net height is lower. In the trial using extension net which has 18.4m in height, there was 27 species (2,030 fishes, 151.7kg). It showed same pattern with existing net in the section I to III, however, in the section IV which is over 13.8m of net height, the catch sharply decreased. The number of species bycaught and the catch of those species using extension net were also same as results using existing net. It showed that section III (9.2-13.8m) where is upper-middle part of the net has caught most of catch and large fishes having over 22cm in length. Through these results, it is judged that the setting depth of the net where is 4.6-13.8m above the sea bottom is the best to reduce bycatch and catch much more large size fishes, and the catch per net is proportional to filtering area of net. Therefore the Fisheries Resource Management Act (the clause 1, article 10) on the amount of usage for offshore drift gill net need to be considered not only length of a net but also net height.

극소저출생체중아의 따라잡기 성장 및 발달평가 (Catch-up growth and development of very low birth weight infants)

  • 마태호;김경아;고선영;이연경;신손문
    • Clinical and Experimental Pediatrics
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    • 제49권1호
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    • pp.29-33
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    • 2006
  • 목 적 : 극소저출생체중아의 따라잡기 성장과 이에 미치는 요인을 분석하고, 발달검사를 통한 따라잡기 성장과 발달의 연관성을 알아보고자 하였다. 방 법 : 2000년 1월 1일부터 2001년 12월 31일까지 삼성제일병원 신생아집중치료실에 입원하였던 1,500 g 미만의 극소저출생체중아 114명 중 추적관찰이 가능한 76명을 대상으로 하여 의무기록을 통한 후향적조사를 하였다. 한국소아의 표준성장곡선을 사용하여 각 환아의 교정연령 24개월의 체중에 따라 10 백분위수 이상인 군을 따라잡기 성공군으로, 10 백분위수 미만인 군을 실패군으로 정하였고, 각 군 산모 및 환아의 임상적 특성과 경과 등을 조사하였다. 그리고 각 군의 BSID II 점수를 비교하였다. 결 과 : 극소저출생체중아의 따라잡기 성장 성공군은 51명, 실패군은 25명이었다. 각 군 산모의 임상적 특성에서는 산전에 부신피질호르몬의 투여가 의미있는 차이를 보였다. 각 군의 임상적 특성에서는 출생체중과 자궁내성장지연이 유의한 차이를 보였으며, 다른 임상적 특성과 경과에서는 유의한 차이가 없었다. 성공군 51명 중 28명, 실패군 25명 중 22명에서 BSID II를 실시하였고, 발달지연은 실패군에서 더 많았지만, 통계상 유의한 차이는 없었다. BSID II 점수의 평균은 성공군에서 운동발달지수와 정신발달지수가 각각 $99.54{\pm}14.82$, $108.18{\pm}12.27$이었고, 실패군에서는 각각 $98.68{\pm}15.24$, $103.82{\pm}15.17$로 성공군의 점수가 더 높았지만, 유의한 차이는 없었다. 결 론 : 본 연구에서 극소저출생체중아의 따라잡기 성장에 영향을 미치는 주요인자는 산전 부신피질호르몬의 투여, 출생체중, 자궁내성장지연이었다. 따라잡기 성공여부와 발달과는 큰 연관은 없었으나 더 많은 증례를 통한 연구가 필요할 것이다.

생분해성 가자미 자망어업의 어획 특성 (Catch characteristics of the biodegradable gill net for flounder)

  • 배봉성;조삼광;박성욱;김성훈
    • 수산해양기술연구
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    • 제48권4호
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    • pp.310-321
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    • 2012
  • There are many studies of the biodegradable net for fishing to prevent marine pollution in Korea and the snow crab gill nets is developed effectively. Recently, the biodegradable gill net for fishes is being developed. This study is the experiment of the catch characteristics for the biodegradable flounder gill net. The 8 experiments were carried out using the nylon gill net and the biodegradable gill net in from August to October, 2011 in the southern East Sea. The results obtained from the above approaches are summarized as follows; A total of 16 species was caught with most dominant species of Cleisthenes pinetorum followed by Liparis tanakai, Glyptocephalus stelleri, Buccinum striatissimum and Dasycottus setiger. A total of catch of the nylon net was 342,885g and that of the biodegradable net was 236,857g. Thus catch of the nylon net was 1.45 times more than that of the biodegradable net. The length composition of Cleisthenes pinetorum, caught by the biodegradable net was very similar to that of nylon. As a result of analysis on the effect of submerged time, small fish escaped more easily than large fish as the submerged time is getting longer. And catches of the biodegradable net was less than the nylon net's as higher as wave height. Wave height was more influential factor for fishing capacity than submerged time based on the results of a comparison between catch difference of two kinds of gill nets and catch characteristics.

새만금방조제 건설로 인한 조업구역의 변경이 전라북도 근해형망어업의 패류어획량에 미치는 영향 (Influence on the catch of shellfish by offshore dredge fishery according to change fishing area to the construction of the Samangeum Dike in Jeollabuk-do, Korea)

  • 최종덕;류동기;이미희
    • 수산해양기술연구
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    • 제53권3호
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    • pp.266-275
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    • 2017
  • The maximum sustained yield (MSY) of shellfish caught through dredge fishery was 7,250 to 7,490 MT from 1990 to 1999, which was not affected by the construction of the Saemangeum Dike. The MSY from 2000 to 2016, under the influence of the dike, was 1,716 to 1,776 MT when the total annual fish catch was 1,000 MT or more, and 289 to 336 MT when it was less than 1,000 MT. The construction of the Saemangeum Dike led to a decrease in the catch volume of the offshore dredge fishery in Jeollabuk-do, to 4.2 to 23.7% of that before its construction. The allowable biological catch (ABC) was estimated to be 313 to 1,532 MT per year, which was about 72.3 to 94.3% less than before the construction of Saemangeum Dike. Currently, the dredge fishery in Jeollabuk-do relies on comb pen shells. For fishery management, the catch per vessel should be set at 51.0 MT/year or less, and the number of fishing vessels should be reduced to 22 as quickly as possible. Besides, in the long term, the number of current fishing vessels should be reduced to less than half in consideration of the comb pen shell collecting period in Jeollabuk-do.

우리나라 대형선망어업의 일본수역 조업특성 분석 (An analysis of the fishing characteristics of Korean large purse seine fisheries in Japanese waters)

  • 유광민;류경진;김형석;이춘우
    • 수산해양기술연구
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    • 제57권2호
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    • pp.107-116
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    • 2021
  • The breakdown of the Korea-Japan fishing negotiations since 2016 has made it impossible for many domestic fishing vessels to operate in the Japanese EEZ water, and large purse seine fishing vessels are one of them. Mackerel is a highly migratory fish species, circulating in the East China Sea, South Sea, West Sea and East Coast throughout the year, and goes through a period of wintering, spawning, growth and feeding migration. In this study, in order to find out the dependence of large purse seine fishing vessels on mackerel fishing in the Japanese EEZ waters, we analyzed the characteristics of mackerel by large purse seine fisheries in the Japanese EEZ waters from 2010 to 2016. The catch and fishing details were investigated. The total catch of mackerel by large purse seine fishery, the average catch rate of mackerel in Japanese EEZ is 4 percent per year. The amount is estimated at 10.2 billion won per year. Although there was an effect, it was not judged to be a significant factor, and it was found that the amount of catch and fish price in the domestic waters had a greater influence on the total catch than the Japanese EEZ waters.

자바카드 플랫폼상에서 자바 클래스 파일의 최적화 연구 (A Study On The Optimization of Java Class File under Java Card Platform)

  • 김도우;정민수
    • 한국멀티미디어학회논문지
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    • 제6권7호
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    • pp.1200-1208
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    • 2003
  • 자바카드 기술은 스마트카드나 메모리 제한적인 장치에서 자바 프로그래밍 언어로 작성된 응용프로그램을 동작 가능하게 한다. 자바카드 기술은 높은 안전성, 이식성, 다중의 응용프로그램을 관리하고 저장하는 기능을 제공한다. 그러나 자바카드 플랫폼의 제한적인 메모리 자원은 다양한 용도로 자바카드가 보급되는데 저해 요인으로 작용하고 있다. 따라서 본 논문에서는 자바카드의 효율적인 메모리 사용을 위해서 바이트코드 최적화 알고리즘을 제안한다. 이 알고리즘은 예외처리 구문 try-catch-finally에서 catch절의 매개변수에 대한 기억장소를 공유하게 함으로써 생성되는 바이트코드의 크기를 줄일 수 있다.

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Generation Human -like Arm Motion to Catch a Moving Object

  • Kwon, Oh-Kyu;Park, Poo-Gyeon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.161.5-161
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    • 2001
  • Robots are required to assist our activities in daily life. In this paper, we focus on arm movement to catch moving object as one of important tasks frequently performed by human. We propose an algorithm which enables a robot to perform human-like arm motion to catch a moving object. First we analyze human hand trajectories and velocity profiles to catch an object. From the experimental results, we extract some characteristics in the process of approaching and following a moving object and confirm that these are necessary to realize human-like motion. We then adopt an instantaneous optimal control method which evaluates the error and energy cost at each sampling step, and design two time-varying weight matrices to introduce human characteristic into robot motion. The matrix concerning the error is defined as a time-increasing ...

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Catch per Unit Effort and Size Composition of Crayfish, Astacus leptodactylus Eschscholtz 1823, in Lake İznik

  • Balik, Ismet;Ozkok, Ergun;Ozkok, Remziye
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권6호
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    • pp.884-889
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    • 2002
  • This paper was carried out from 15 June to 24 December in 2000 in Lake İznik of Turkey, to determine catch per unit effort (CPUE) and size composition of crayfish, Astacus leptodactylus Eschscholtz 1823, captured by fyke-nets of local fishermen. The average CPUE of all size groups was found as 1.65 crayfish/fyke-net/night for fishing season in 2000, but 26.4% of which was below the legal minimum size (crayfish<90 mm). The average CPUE of legal-sized (crayfish$\geq$90 mm) crayfish was 1.10 crayfish/fykenet/night. The annual catch of crayfish was estimated as 2990 tonnes. The length and weight compositions of crayfish captured in the fyke-nets have varied between 60 and 130 mm, and 6 and 71 g, respectively. The mean length and weight were found as 95.5 mm and 28.8 g for all size groups and 100.1 mm and 33.0 g for legal-sized individuals.

동해안 울진해역 원통형 고둥 통발의 재질별 어획 성능 (Catching efficiency of the whelk pot in accordance with the pot materials in the Uljin waters, East sea)

  • 안희춘;배재현;박창두;박종명;홍성익;윤병선;김병관;김성훈
    • 수산해양기술연구
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    • 제53권1호
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    • pp.1-11
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    • 2017
  • Fishing pots are one of the important fishing gears in our coastal and offshore fisheries. In terms of a sustainable use of marine resources, there are concerns about the ghost fishing by lost pots. It is reported that 10 to 70% of the pots are abandoned or lost annually. This study is to compare the catching efficiency of drum type whelk pots that are made of biodegradable nets to those made of the ordinary nets, in the eastern coast of Korea. Five types of drum pots were used with combination of biodegradable nets and ordinary (PA, PE) nets applied to the main and funnel parts of the pots: pots with biodegradable nets (Bio+Bio); pots with PE net (PE+PE); pots with body and funnel made of biodegradable nets and PE nets respectively (Bio+PE); pots with body and funnel made of PE nets and PA nets respectively (PE+PA); pots with body and funnel made of PE nets and biodegradable net respectively (PE+Bio). Field experiments were conducted from June $18^{th}$, 2015 to August $7^{th}$, 2015 using a commercial fishing vessel in the Uljin waters on the eastern coast of Korea. Two fleets of pots with one hundred in each, 20 pots of each type, were casted for 8 to 15 days to analyze their catching efficiency. The catch of target species, whelks, was 202,563.0 g with catch rate of 38.7% of the total catch, while the bycatch was 320,709.7 g with the rate of 61.3% of the total catch. The catch of whelks was the highest in the Bio+PE pots (46,020.3 g), followed by the Bio+Bio pots (42,027.5 g), the PE+Bio pots (41,849.9 g) and the lowest being PE+PE pots (38,054.2 g). Compared to the conventional pots, the pots with biodegradable nets on the body or entrance part had slightly higher catch rate for both the target species and the bycatch. The PE+PE had the lowest catch rate. There is no significant difference in catch between the pots with biodegradable nets and the ordinary nets for the target species such as Buccinum opisthoplectum, Neptunea eulimata, Buccinum striatissimum. Consequently, using biodegradable nets for the conventional whelk pots can reduce ghost fishing by lost gears while keeping the performance of the pots.