• Title/Summary/Keyword: 회유성

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Assessment of Ascending Capacity of Migratory Fish in Fishways by Eco-hydraulic Experiments (I) - Baffled Fishways - (어도 생태수리실험에 의한 회유성 어류의 소상능력 평가(I) - 사다리식 어도 -)

  • Park, Sang-Deok
    • Journal of Korea Water Resources Association
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    • v.34 no.4
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    • pp.365-379
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    • 2001
  • This paper presents an echo-hydraulic experimental approach to assessment of ascending capacity of migratory fish in a baffled fishway. Sweetfish, Plecoglossus altivelis, trout, Oncorhynchus mykiss, are used in these experiments. Ascending environment of the migratory fish in rivers is analyzed through the results of taco-hydraulic experiments. Important factors affecting the ascending capacity of migratory fish in baffled fishways are the discharge and slope of fishways and the fall height between the fishway entrance and the river bed. In these fishways the migratory capacity of sweetfish for a given fishway discharge is mainly affected by fishway slope, whereas the ascending capacity of trout for a given fishway slope was influenced by the change of fishway discharge. Loss of ascending properties of landlocked salmon, Oncorhynchus masou var ishikawai, was confirmed by these experiments. An ascending hydraulic criteria of the baffled fishway is defined by means of dimensionless factor F$_{f}$ and falling head H$_{f}$. Ascending capacity of migratory fish in existing baffled fishways in river of eastern coastal region is poor because the slope of fishways is verb steep.eep.

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Assessment of Ascending Capacity of Migratory Fish in Fishways by Eco-hydraulic Experiments (II) (어도 생태수리실험에 의한 회유성 어류의 소상능력 평가(II) - 계단식 어도 -)

  • Park, Sang-Deok
    • Journal of Korea Water Resources Association
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    • v.34 no.4
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    • pp.381-390
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    • 2001
  • This is to evaluate the ascending capacity of migratory fish in the pool and weir type fishways. Ascending environment of the migratory fish in rivers is analyzed through eco-hydraulic experiments using sweetfish, Plecoglossus altivelis, trout, Oncorhnchus mykiss, and surveying the fall height of existing pool and weir type fishways. When the fall height is less than 16.0cm, the ascending capacity of sweetfish in the pool and weir type fishways is greater than trout. On the other hand when the fall height is over 20.0 cm, the ascending capacity of trout is greater than sweetfish. A sweetfish may prefer to jump for upward moving than trout. And its endurance after upward jumping over wear is greater than that of sweetfish. Because of high fall height of existing pool and weir type fishways the migratory environment in rivers is so poor. When the pool and weir type fishways are designed and constructed in river the fall height of weir must be considered for the variety of migratory fish living in river and the fall height of weir less than 20.0cm is suggested.

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The Fish Migration through Fishlock at Youngam Lake (영암호 갑문식어도를 통한 어류의 회유)

  • Hwang, Jong-Seo
    • Journal of Korea Water Resources Association
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    • v.33 no.5
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    • pp.561-568
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    • 2000
  • The dimension of the fishlock at the Youngam Lake is 6.6m wide and 30m long, and it has been used for both fish migration and ship passage. The capacity of attraction freshwater is $0.172\;\textrm{m}^3/s$, and the water depth of the fishlock varies between 1.9m - 5.7m due to the tide. Fishes were sampled weekly by using 3m wide maze net from April to June, 1999, and by using purse seine covering the entire space of fishlock from July to November, 1999. 116,014 samples were comprised of 25 species, and 99.5% of the samples were 10 kinds of diadromous fishes. The order of the diadromous fishes in abundance was Hemirhamphus kurumeus, Hypomesus olidus, Coilia ectens, and Mugil cephalu, where these four species consist 99% of the individuals, and the other six species contribute only a few of individuals. Each species had unique peak migration period. The peak migration of Hypomesus olidus, Mugil cephalus, Coilia ectens, and Hemirhamphus kurumeus happened on July 20, July 15, May 10, and May 1, respectively.tively.

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근해안강망어업의 주간어황예측

  • 김진영;황진수;홍승현;연인자;임양재;황학진;김지연
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2000.05a
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    • pp.344-345
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    • 2000
  • 근해안강망어업에서 주로 어획되는 수산자원은 참조기, 갈치, 아귀등의 저서성어류로서, 겨울에는 월동장인 우리나라 서해남부 및 동중국해 북부해역으로 남하회유하고 봄이 되면 황해 및 중국 연안의 산란장으로 북상이동하는 계절회유를 한다. 따라서 근해안강망어업의 주간어황은 황해 및 동중국해에 서식하는 대상어업자원의 자원량변동의 영향을 받으며, 해황의 변동에 따른 회유경로의 경년변동 및 계절회유에 의한 주 서식처의 변동, 조석의 변동, 어장의 일기등의 영향을 받는다. (중략)

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연어과 어류의 초기 발생단계에 있어서의 염분내성에 관한 연구

  • 여인규;최미경
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.10a
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    • pp.263-264
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    • 2001
  • 일반적으로 회유성 어류인 연어과 어류는 치어기에 강에서 바다로 회유를 하기 직전에 해양환경에 대한 적응을 하기 위해 생리적인 변화를 가진다. 연어과 어류의 치어는 담수에서 해수로 이행하는 시기에 사망률이 높고, 이것은 해수에 대한 저항성의 차이에 의해 일어나는 것으로 알려져 있다. 그렇기 때문에 치어기의 염분저항성을 결정하는 요인을 분석하는 것은 수산학에 있어 중요한 부분이라고 할 수 있다. (중략)

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여수연안에 분포하는 어류군집의 종조성과 계절변동

  • 김영혜;김종빈;장대수
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2002.10a
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    • pp.268-269
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    • 2002
  • 전남 다도해형 바다목장 후보지인 여수연안이 각종 어류의 산란장 및 색이장으로서 외해로부터 고온, 고염분의 외해수가 연중 공급되고 이들의 해수는 내만 쪽의 연안수와 혼합되고 외해로부터 회유성 어류들이 내유함으로써 이들 어류들의 좋은 성육장이 되고 있다(Kim, 1993). 정치망은 어군을 적극적으로 쫓아서 어획하는 것이 아니고 어군이 연안으로 내유하기를 기다려 잡는 소극적인 어업 방법이므로, 어획물은 그 지역의 해황의 변화에 따라 회유하여온 어류들로 구성되어 있을 것이다. (중략)

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원료의 어획지 차이에 따른 시판 마른멸치의 식품성분 특성 비교

  • 김진수;조문래;심효도;김혜숙;허민수;오광수;이정석
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.10a
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    • pp.109-110
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    • 2001
  • 멸치는 청어목 멸치과에 속하는 어종으로서 몸체가 길고, 원통형이며, 등쪽은 암청색, 배는 은백색을 나타내고 있고, 몸체의 비늘은 탈락하기 쉽다. 또한 멸치는 플랑크톤을 주식으로 하면서 주광성이고, 산란, 성장 적정수온이 23$^{\circ}C$ 이상인 난류성이며, 표층 및 중층의 연안을회유표층 및 중층의 연안을 회유하는 회유어로 군유하는 성질이 있다. (중략)

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DUPIC scrap waste의 석탄회유리고화체에 대한 내침출성 분석

  • 박장진;김종호;전관식;신진명;조영현
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.05b
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    • pp.319-323
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    • 1997
  • 석탄화력발전소의 부산물인 석탄회를 이용한 DUPIC dirty scrap waste의 유리고화체에 대한 내침출성을 분석하였다. Fly ash, SiO$_2$, NaNO$_3$, B$_2$O$_3$에 DUPIC 핵연료 제조공정으로부터 발생되는 모의 dirty scrap waste를 15 wt% ~ 30 wt% 혼합하여, 115$0^{\circ}C$ 에서 3시간 용융시킨 후 서서히 냉각시켜 얻은 유리고화체의 침출성을 온도, 침출액의 종류, 폐기물의 함량 등에 따라 평가하였다 침출실험결과 석탄회유리고화체는 양호한 내침출성을 보였다. 석탄회유리고화체의 침출율은 합성지하수, 합성해수, 증류수의 순으로 감소하였으며, 폐기물함량의 증가에 따라 증가하였다.

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Changes in fish species composition after fishway improvement in Songrim weir, Yeongok stream (연곡천 송림보에서 어도의 개선에 따른 어류 종 조성 변화)

  • Yun, Young-Jin;Kim, Ji Yoon;Kim, Hye-Jin;Bae, Dae-Yeol;Park, Gu Seong;Nam, Chang Dong;Lim, Kyung Hun;Lee, Moon-Yong;Lee, Seong-Yong;Moon, Kyeong-Do;Lee, Eui-Haeng;An, Kwang-Guk
    • Korean Journal of Environmental Biology
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    • v.39 no.2
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    • pp.195-206
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    • 2021
  • In 2020, South Korea initiated research and development of a longitudinal connectivity evaluation between upstream and downstream based on stream ecosystem health. This study analyzed the migration of upstream and downstream migratory fish species, fish distribution characteristics, trophic guilds, tolerance guilds, and species composition changes from 2015 to 2020 at Songrim weir in Yeongok stream, where the cross-structure of an ice harbor-type fishway for fish movement was recently improved. A total of 5,136 fish, including 36 species, were collected and three major migratory fishes were identified, namely, Tribolodon hakonensis, Plecoglossus altivelis altivelis, and Oncorhynchus keta. According to the comparative analysis before (Pre-I) and after (Post-I) improvement of the fishway, the relative abundance of primary freshwater fish increased in the upstream section, while the number of migratory fishes decreased. The fish species that used the fishway in the Songrim weir were Tribolodon hakonensis (58.4%) and Plecoglossus altivelis altivelis(11.8%). According to the Wilcoxon Signed-Rank Test migratory fish showed a statistically significant difference (p<0.05) in the upstream and downstream, showing a biological improvement effect of the crossstructure. On the other hand, the annual change of migratory fish based on the MannKendall trend test did not significantly increase or decrease (p>0.05). Therefore, in the fish passage improvement project, it is necessary not only for physical, hydrological, and structural tests, but also for pre- and post-biological tests on the use and improvement effect of fishway.

A Study on the Method for Increasing Customer's Circulation in Large-Scale Retail Store (대형 소매점에서 내점객의 회유성을 증대시키는 레이아웃에 관한 연구)

  • 백승환;류호창
    • Korean Institute of Interior Design Journal
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    • no.15
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    • pp.69-78
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    • 1998
  • Purchasing should be considered as an exciting entertainment by itself in these days. Customers can be satisfied with making their own choices and dreaming of their better lives through the action of buying,. However the customers are not rushing into stores without any special reason except when the store has something attracts them. Generally speaking the customers will willingly spend their time and effort in shopping only when they are attracted by well-displyed goods and reasonably planned layout. Based upon these concepts interior design as a creative marketing tool plays a great role in enhancing customer's circulation and the productivity of a store. This study is to propose the layouts which are increasing the customer's circulation by contacting the customers with commodities as many as possible. This study is primarily revolved around the parts affecting customer's circulation among the factors of store's layouts. This study was consist of theoretical consideration about the store's layouts on the foundation of conference and existing works and several proposals. The results of this research are as below: 1) The entrance and exit of a retail store should be apart from each other to increase customers' circulation. It is regarded as ideal to locate the entrance on the right side of front to control moving line of customers. 2) A shop should be surrounded with the main aisles which is straightened inward from the main entrance. 3) Placing magnets which can be anything that attracts customers' attention at the corner of store can lead customers inward and increase customers' circulation.

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