• 제목/요약/키워드: Fish Conference

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Ichthyotoxicity of a harmful dinoflagellate Cochlodinium polykrikoides: Aspect of biochemical and hematological responses of fish exposed to Algal blooms

  • Kim, Chang-Sook;Bae, Heon-Meen;Cho, Yong-Chul
    • 한국어업기술학회:학술대회논문집
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    • 한국어업기술학회 2000년도 추계수산관련학회 공동학술대회발표요지집
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    • pp.141-142
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    • 2000
  • To elucidate the ichthyotoxic mechanisms of a harmful dinoflagellate Cochlodinium polykrikoides, biochemical and hematological responses of fish exposed to blooms were investigated. Particularly, based on our finding that oxidative damages of gill were associated with fish mortality, dysfunction of ion-transporting enzymes and secretion of gill mucus of fish exposed to this bloom species were examined. (omitted)

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Brackish Lakes in Shinpo District North Korea. III. Fish

  • Gil, Joon-Woo;Hong, Young-Pyo;Park, Joon-Ho;Kim, Saywa
    • 한국환경생물학회:학술대회논문집
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    • 한국환경생물학회 2004년도 학술대회
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    • pp.23-23
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    • 2004
  • Four times of field survey were carried out to collect fish samples at six stations in Shinpo district, North Korea in October 1997, July 1998, May and October 2002. Sampling stations were located in upstream, middle and down of the southern river of Bukchong and three brackish lakes of lake Hommanpo, Daein and Hyunkum, respectively. A total of 29 species belonging to 11 families occurred. Family Cyprinidae showed the prosperity in species number of 28% among total species occurred. No natural monument fishes or rare species were captured. Ten commercial fishes, five anadromous ones and five brackish ones were identified. Feeding habits divided fish fauna with 11 carnivores, two herbivores and seven omnivorous ones. In the river, 20 species belonging to seven families inhabited, 18 species of 6 families in lake Homanpo, 21 of seven III Hyunkum and 23 of eight in Daein, respectively. Ecological indices of richness, diversity and evenness were highest in lake Daein and dominance index was highest in lake Hyunkum.

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Antimicrobial effect of chitosan oligosaccharides, prepared under ultrafiltration membrane bioreactor, against pathogenic bacteria causing flounder fish diseases in aquacultural farm

  • Heo, Moon-Soo;Jeon, You-Jin;Lee, Ki-Wan;Song, Choon-Bok;Lee, Jehee;Yeo, In-Kyo;Yang, Byung-Gyoo;Kim, Se-Kwon
    • 한국어업기술학회:학술대회논문집
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    • 한국어업기술학회 2001년도 추계 수산관련학회 공동학술대회발표요지집
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    • pp.145-146
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    • 2001
  • Despite a variety of development in fish farming during the last decades, fish diseases by bacteria, virus, and parasites are still major problems in aquaculture. Aquaculture of Hounder fish is widely performed around Korea as well as Jeju island, due to relatively stable seed production, short farming period, and a higher value in market. However, intensive feeding and environmental pollution in aquacutural farm act as a great limiting factor in economic aspect. (omitted)

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Comparisons of Fish Communities in Ledbetter Creek and Ledbetter Embayment of Kentucky Lake, Kentucky, USA

  • Seo, Jinwon;Timmons, Tom J.
    • 한국환경생물학회:학술대회논문집
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    • 한국환경생물학회 2002년도 학술대회
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    • pp.137-140
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    • 2002
  • To determine if fish density, biomass, species richness, and species diversity were greater in ecotone than the stream and littoral zones, I sampled fish monthly in the Ledbetter Creek through Ledbetter Creek Embayment in Kentucky Lake, Kentucky, from April to October 1996 by using throw traps. During the first four months (daytime only) fish density did not vary significantly among zones or among months. However, there were significant differences among zones during the last three months and the stream zone had significantly higher mean fish density than both the littoral zone and the ecotone. Fish biomass also differed significantly among zones during the last three months. The stream zone had the highest mean fish biomass among zones, significantly higher than the ecotone, but not different than the littoral zone. There were no statistically significant differences among zones during the first four months, but mean fish biomass in the stream zone was about eight times higher than the ecotone, The stream zone had the highest fish species richness among zones. Differences were significant among zones during the last three months, and the stream zone (0.98 $\pm$ 0.04) had significantly greater mean fish species richness than the ecotone (0.45 $\pm$ 0.01), but not significantly than the littoral zone (0.56 $\pm$ 0.17). Fish species richness differed significantly among months during the first four months, Monthly species diversities ranged from 0.62 to 1.96 in the stream zone, 0 to a.57 in the ecotone, and 0 to 2.60 in the littoral zone. Combined species diversities in the stream, the ecotone , and the littoral zones were 2.72, 3.58, and 3.10, respectively, There were five families of fishes captured frequently enough for their individual numbers to comprise at least 8 % of the total. Family rankings in the stream zone were opposite of the littoral zone. Percidae was the most abundant family and Clupeidae was absent in the stream zone, whereas Percidae was uncommon and Clupeidae was the most abundant family in the littoral zone. Atherinidae was dominant in the ecotone. Five of the most abundant species comprised 65 % of the total number. The guardian darter occurred only in the stream zone, and it was consistently found in riffles. Longear sunfish and central stoneroller also had significant differences of mean fish densities among zones, and they were found mostly in the stream zone. Threadfin shad and bullhead minnow were almost exclusively caught in the littoral zone. I finally concluded that the ecotone between the stream and the littoral zone in this small-scale freshwater aquatic ecosystem was not as productive as the ones in other ecosystems.

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Utilization of fermented skipjack tuna viscera as a dietary protein source replacing fish meal or soybean meal for juvenile abalone Haliotis discus hannai

  • Lee, Sang-Min;Kim, Kyoung-Duck;Kim, Tae-Jin
    • 한국양식학회:학술대회논문집
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    • 한국양식학회 2003년도 추계학술발표대회 논문요약집
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    • pp.73-73
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    • 2003
  • This study was carried out to evaluate the utilization of fermented skipjack tuna viscera (FSTV) in the diet for juvenile abalone Haliotis discus hannai. Lactobacillus bulgaricus was used for fermentation of skipjack tuna viscera. Eight isonitrogenous (about 30% crude protein) diets were formulated to include different levels (0%, 10%, 20% and 30%) of FSTV as a replacer of either dietary fish meal or soybean meal. Three replicate groups of abalone were fed the experimental diets containing different levels of FSTV for 7 weeks. The inclusion of FSTV up to 30% in fish meal-based diet had no significant effect on survival, body weight, shell growth, and proximate composition of abalone (P>0.05). Weight gain of abalone fed the diet substituting 10% FSTV for soybean meal was not significantly different to that of abalone fed the control diet, however this value decreased in abalone fed the 20% and 30% FSTV (P<0.05).The contents of crude protein and lipid of soft body in abalone fed soybean meal-based diets were significantly affected by dietary FSTV level (P<0.05). The results of this study indicate that FSTV can be used as a partial substitute protein source for fish meal or soybean meal in the formulated diet for juvenile abalone.

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사이버 아쿠아리움 구축을 위한 어류속성 편집기 개발 (Development of a Fish-trait Editor for Constructing Cyber Aquarium)

  • 강경헌;정승문;이현철;김은석;허기택
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2006년도 추계 종합학술대회 논문집
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    • pp.528-532
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    • 2006
  • 사이버 아쿠아리움을 구성하는 요소들 중 어류 객체의 행동방식은 사용자의 시각적인 측면에서 가장 중요한 요소이다. 본 논문은 어류 객체들의 생명력, 이동량, 분포 가능한 최대 수심 및 식성 주기 등의 주요 습성들을 분석하고, 이에 따른 움직임, 다른 어류 객체들과의 상호작용, 평균 수명 데이터를 조정함으로써 해저 생태계의 균형을 시뮬레이션 하는 방법을 제안한다. 제안 방법은 어류 객체의 고유 속성값을 자유롭게 변경시킴으로써, 다양한 해저환경을 표현하는 사이버 아쿠아리움, 수족관 화면 보호기, 물고기 육성 게임 등에 활용되어질 수 있다.

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Semiautomatic 3D Virtual Fish Modeling based on 2D Texture

  • Nakajima, Masayuki;Hagiwara, Hisaya;Kong, Wai-Ming;Takahashi, Hiroki
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 1996년도 Proceedings International Workshop on New Video Media Technology
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    • pp.18-21
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    • 1996
  • In the field of Virtual Reality, many studies have been reported. Especially, there are many studies on generating virtual creatures on computer systems. In this paper we propose an algorithm to automatically generate 3D fish models from 2D images which are printed in illustrated books, pictures or handwritings. At first, 2D fish images are captured by means of image scanner. Next, the fish image is separated from background and segmented to several parts such as body, anal fin, dorsal fin, ectoral fin and ventral fin using the proposed method“Active Balloon model”. After that, users choose front view model and top view model among six samples, respectively. 3D model is automatically generated from separated body, fins and the above two view models. The number of patches is decreased without any influence on the accuracy of the generated 3D model to reduce the time cost when texture mapping is applied. Finally, we can get any kinds of 3D fish models.

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Formaldehyde residues in olive flounder(Paralichthys olivaceus) and black rockfish(Sebastes schlegeli) exposed to formalin, and in formalin-treated seawater

  • Jung, Sung-Hee;Kim, Jin-Woo;Sohn, Sang-Gyu
    • 한국어업기술학회:학술대회논문집
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    • 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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    • pp.233-234
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    • 2000
  • Formalin, 37% formaldehyde, has been employed as a chemical for controlling ectoparasites and aquatic fungi responsible for infectious fish of diseases in hatcheries and culture facilities (Roberts, 1978; Schnick, 1991; Rach et al., 1997). Regarding the commercial usage of formaldehyde in the aquaculture industry, the U.S. Food and Drug Administration (FDA) approved three commercial products as parasiticides in a species-specific manner: Paracide-F and Formalin-F for bluegill, catfish, largemouth bass, salmon, and trout and Parasite-S for all finfish (FDA, 1998). Withdrawal time for these products was legally zero when used as permitted under the regulations. With the increased production of cultured fish in Korea, such as olive Hounder Paralichthys olivaceus and black rockfish Sebastes schlegeli, application of formalin to diseased fish has become more frequent. Moreover, there is still some concern about environmental exposures caused by effluents from fish culture facilities. The purpose of the present study was to evaluate residues in fish resulting from therapeutic usage of formalin in the aquaculture industry and to document the rate of disappearance of formaldehyde in seawater treated with formalin. (omitted)

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양식장 환경 데이터 모니터링 및 예측 시스템의 설계 (Design of the Environmental Data Monitoring and Prediction System for the Fish Farms)

  • 리타 리자얀티;아쉬위니 카담;아리아 비스마 와휴타마;이본영;황민태
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2021년도 춘계학술대회
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    • pp.178-180
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    • 2021
  • 본 논문에서는 바다 환경의 변화로 인한 양식장의 피해를 막을 수 있도록 양식장의 환경 데이터를 실시간 모니터링하고 기계 학습 기반의 예측 서비스를 제공하는 시스템 설계를 다룬다. 제안 시스템은 양식장의 주요 위치에 수소 농도, 염도, 용존 산소량 그리고 수온을 측정할 수 있는 센서들로 구성되는 사물인터넷 기반의 디바이스 모듈을 설치하며, 이들로 부터 수집한 데이터는 LTE 또는 LoRa 통신 기술을 이용해 클라우드 DB로 전송한 후 웹사이트나 모바일 애플리케이션을 통해 실시간으로 양식장의 환경 데이터 모니터링을 가능하게 한다. 아울러 수집된 데이터를 활용한 기계학습 기반의 예측 기술을 적용해 양식장의 환경 변화에 미리 대비할 수 있도록 하는 기능을 가진다.

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Adverse Reproductive Effects on Plasma Vitellogenin and Sex Steroid Levels, and Gonadosomatic Index in Juvenile Common Carps (Cyprinus carpio) Exposed to 17$\beta$-Estradiol and D-2-Ethylhexyl Phthalate

  • Seo, Jinwon;Park, Kyung-Seo;Moon, Woon-Gi;Lee, Sung-Kyu
    • 한국환경생물학회:학술대회논문집
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    • 한국환경생물학회 2002년도 학술대회
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    • pp.141-144
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    • 2002
  • Environmental estrogens are natural or synthetic substances present in the aquatic environment, especially in effluent from sewage treatment. However, the adverse effects of these estrogenic substances on fish reproduction are unknown. Di-2-ethylhexyl phthalate (DEHP) is the most common phthalate, which Ps used as a plasticizer in polyvinylchloride (PVC), and it is widespread in the environment and has been found in aquatic organisms and sediments. Therefore, juvenile common carps (Cyprinus carpio) were exposed to nominal concentrations of 17$\beta$-estradiol (E2) (0.5, 5, 50 $\mu\textrm{g}$/L) and DEHP (10, 100, 500 $\mu\textrm{g}$/L) for 21 days, to determine the adverse reproductive effects of these compounds on plasma vitellogenin (VTG) induction, sex steroid level, and gonad weight. Electrophoresis (SDS-PAGE) revealed that much of VTG was induced in fish exposed to 5 and 50 E$_2$ $\mu\textrm{g}$/L, but none of DEHP exposure showed induction. Enzyme-linked immunosorbent assay (ELISA) revealed that VTG was significantly induced in fish exposed to 5 and 50 E$_2$ $\mu\textrm{g}$/L, and combination of 50 E$_2$ $\mu\textrm{g}$/L with 10 and 500 DEHP $\mu\textrm{g}$/L, but none of DEHP exposure showed induction. Analysis of sex steroid levels in some fish revealed that testosterone (T) was detected in both male and female fish of the control and DEHP exposures, but none of fish exposed to 22 concentrations had detectable testosterone level. On the other hand, E$_2$ exposure induced 17$\beta$-estradiol in plasma of male fish, but there was no induction of 17$\beta$-estradiol in plasma of male fish exposed to DEHP. Comparison of gonadosomatic index (GSI) revealed that maximal E$_2$ exposure inhibited ovarian growth, but maximal DEHP exposure stimulated testicular growth. The results indicated that those comparisons can be a useful bio-indicator for determining adverse reproductive effect of endocrine disrupting chemicals (EDCs).

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