• Title/Summary/Keyword: 광주기

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Induced Spawning of Striped Knife-Jaw, Oplegnathus fasciatus by Manipulating Water Temperature and Photoperiod (수온 및 광주기 조절에 의한 돌돔, Oplegnathus fasciatus의 산란 유도)

  • 정관식;김석민;방인철;김성연;이원교
    • Journal of Aquaculture
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    • v.11 no.2
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    • pp.141-149
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    • 1998
  • Spawning inducement of striped knife-jaw, Oplegnathus fasciathus, was attempted by two experiments. In experiment I (Exp. I), water temperature was gradually increased from 14.5$^{\circ}C$ in December 15, 1996 to $21.0^{\circ}C.$ in February 22, `997 and then maintained at this level. Photo-period was also gradually increased from 10.5L/13.5D in December 15, 1996 to 15.5L/8.5D in February 17, 1997, and then maintained at this level. In experiment II (Exp. II), water temperature was increased in the same way from Exp. I. Photoperiod was natural conditions from December 1996 to March 9, 1997, and then suddenly increased to 15.5L/8.5D until the end of experimental period. Spawning of the fish was occurred from February 22 through April 2, 1997 (for 40 days) in Exp. I. Number of total spawned eggs was 30.04 million and fertilization rate was 77.2%. The fish began to spawn at $21.0^{\circ}C.$ and 15.5L/8.5D. It requied 65 days to spawn since the water temperature had increased from $14.5^{\circ}C.$ to $21.0^{\circ}C.$. Spawning of the fish was not occurred until March 9, 1997 in Exp. II. After 7 days, photo-period was suddenly incresed to 15.5L/8.5D and fish were spawned from March 17 through April 4, 1997 (for 20 days). Number of total spawned eggs was 21.28 million and fertilization rate was 72.1%. The fish began to spawn at $21.0^{\circ}C$ and 15.5L/8.5D. It required 65 days to spawning since the water temperature had increased from $14.5^{\circ}C$ to $21.0^{\circ}C$.

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Estimation of Contribution by Pollutant Source of VOCs in Industrial Complexes of Gwangju Using Receptor Model (PMF) (수용모델(PMF)을 이용한 광주산업단지 VOCs의 오염원별 기여도 추정)

  • Park, Jin-Hwan;Park, Byoung-Hoon;Kim, Seung-Ho;Yang, Yoon-Cheol;Lee, Ki-Won;Bae, Seok-Jin;Song, Hyeong-Myeong
    • Journal of Environmental Science International
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    • v.30 no.3
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    • pp.219-234
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    • 2021
  • Industrial emissions, mainly from industrial complexes, are important sources of ambient Volatile Organic Compounds (VOCs). Identification of the significant VOC sources from industrial complexes has practical significance for emission reduction. VOC samples were collected from July 2019 to June 2020. A Positive Matrix Factorization (PMF) receptor model was used to evaluate the VOC sources in the area. Four sources were identified by PMF analysis, including coating-1, coating-2, printing, and vehicle exhaust. The coating-1 source was revealed to have the highest contribution (41.5%), followed by coating-2 (23.9%), printing (23.1%), and vehicle exhaust (11.6%). The source showing the highest contribution was coating emissions, originating from the northwest to southwest of the sample site. It also relates to facilities that produce auto parts. The major components of VOC emissions from the coating facilities were toluene, m,p-xylene, ethylbenzene, o-xylene, and butyl acetate. Industrial emissions should be the top priority to meet the relevant control criteria, followed by vehicular emissions. This study provides a strategy for VOC source apportionment from an industrial complex, which is helpful in the development of targeted control strategies.

Induced Spawning of Red Sea Bream, Pagrus major, by Controlling Photoperiod and Water Temperature (참돔, Pagrus major의 광주기 및 수온조절에 따른 조기산란)

  • Kim Hyung-Bae;Kim Jong-Man
    • Journal of Aquaculture
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    • v.3 no.1
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    • pp.1-11
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    • 1990
  • To induce an early spawning, the adult red sea bream, Pagrus major, were exposed to predesignated condition of photoperiod and water temperature during February 21 to June 30, 1988. Spawning began from April 20, a month earlier than that in the natural condition, when the photoperiod and water temperature were controlled at 14L: l0D and $17.0^{\circ}C$, respectively, and the spawning continued until June 15, 1988. There were no particular differences between fish under the controlled condition and those in natural condition in terms of the fertilization rate, surface floating rate, the number of oil glouble and the hatching rate.

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Real-time Cloth Simulation in Augmented Reality Environments (증강현실 환경에서의 실시간 옷감 시뮬레이션)

  • Park, Min Ki;Kim, Hyun Soo;Choi, Han Kyun;Lee, Seung Joo;Lee, Kwan H.
    • Proceedings of the Korea Information Processing Society Conference
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    • 2009.04a
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    • pp.212-215
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    • 2009
  • 옷감 시뮬레이션은 지금까지 게임, 애니메이션, 영화 등에 많이 사용되어왔고, 현재 증강현실(Augmented Reality) 환경에서의 교육자료, 쇼핑몰 뿐만 아니라 휴대용 게임기, 휴대폰 등 모바일 기기에서도 그 응용이 점점 증가하는 추세다. PC에 비해 그래픽스 하드웨어의 성능이 떨어지는 기기에서 3차원 시뮬레이션을 가능하게 하기 위해서는 모델의 움직임을 최대한 근사(Approximation)하면서 계산 속도를 보장하는 방법이 필요하다. 즉, 상호작용(Interaction)이 필요한 사용자 입장에서는 최소한의 정확성만 보장한다면 실시간 시뮬레이션이 더 큰 이슈가 된다. 따라서 이 논문에서는 증강현실 환경에서 실시간 시뮬레이션을 보장하는 옷감 시뮬레이션 방법을 제안한다. 안정성과 정확성이 보장되는 적분법(Integration)을 사용하였고, 옷감의 길이가 비사실적으로 늘어나지 않게 하기 위해 제약 조건(Constraints)을 주었다. 또한 각 지점에서의 곡률(Curvature)을 고려하여 충돌 검사를 함으로써 옷감 내부 충돌 검사로 요구되는 많은 계산량을 효율적으로 처리하였다.

Zoeal Stages of Aipheus euphrosyne richardsoni Yaldwyne, 1971 (Decapoda: Macrura: Alpheidae) Reared in the Laboratory (Aipheus euphrosyne (새우아목, 딱총새우과)의 Zoea 유생)

  • 양회정;김창현
    • The Korean Journal of Zoology
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    • v.39 no.1
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    • pp.106-114
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    • 1996
  • Zoeae of Alpheus euplirosyne rlchardsoni Valdwyne, 1971 reared in the laboratory are described and Illustrated The culture was carded out under the laboratory condition with the photoperiod l4hr light and lOhr darkness and salinity of 33.3$\textperthousand$ at 25$^{\circ}$C. This species exhibits extended development on the egg size just before hatching and on the length of the first zoea. The morphological differences between the first zoea of this species and those of five other species in the same genus are discussed.

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Effects of Photoperiod on Oviposition and Emergence of Egg Parasitoid, Trichogramma dendrolimi Mastumura (Hymenoptera, Trichogrammatidae) (광조건이 송충알벌(벌목, 알벌과)의 산란과 우화에 미치는 영향)

  • 박영규;이해풍;이기상;한만위;이정운
    • Korean journal of applied entomology
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    • v.38 no.2
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    • pp.93-99
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    • 1999
  • We investigated the effect of constant photoperiod (16L : 8D, 12L : 12D, 8L : 16D), on the oviposition, parasitism, and emergence of Trichogramma dendrolimi. Also during 16L : 8D condition circadian, oviposition and emergence of this species on artificial eggs were checked every 2hrs. When twelve eggs of Antheraea pern~i and artificial eggs were provided, the wasps had the highest rate of oviposition in the first day, and decreased dramatically there after. In these different photoperiod, the total oviposition numbers per A. pernyi eggs by the wasp were 161.8 in 16L : 8D, 145.8 in 121 : 12D and 128.5 in 8L : 16D respectively in the first day. On the other hand for the artificial egg in 16L : 8D photoperiod, the total oviposition number per egg was 106.8 in the first day, 26.6 in the 2nd day and 21.3 in the 3rd day. The rate of emergence from A. pernyi eggs was not different depend on wasp's day age, however in the artificial eggs, after the first day's 84.7% decreased considerably. The emergence rate from artificial eggs was the highest comparatively between 04:OO-0600 hours.

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Oxygen Consumption of Far Eastern Catfish, Silurus asotus, on the Different Water Temperatures and Photoperiods (참메기, Silurus asotus의 수온과 광주기 변화에 따른 산소 소비량)

  • JO Jae-Yoon;KIM Youhee
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.1
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    • pp.56-61
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    • 1999
  • Oxygen consumption rate of Far eastern catfish, Silurus asotus, weighing 280g, was measured using continuous flow respirometry chamber linked computer monitoring system. Mean oxygen consumption rates at $15^{\circ}C,\;20^{\circ}C,\;25^{\circ}C$, and $30^{\circ}C$ were ranged in 35.2$\~96.4mg\;O_2/kg$ fish/hr, 78.6$\~127.9mg\;O_2/kg$ fish/hr, 120.1$\~231.7mg\;O_2/kg$ fish/hr, and 197.5$\~352.3mg\;O_2/kg$ fish/hr, respectively. The oxygen consumption rates increased with increasing water temperature (p<0.05). A photoperiod-mediated oxygen consumption rates was higher during the light period than during the darkness (P<0.05). When acclimated with different photoperiods, 24L:0D, 12L:12D, and 0L:24D, the lowest oxygen consumption rate was observed in the continuous darkness (0L:24D). The differences between maximum and minimum oxygen consumption rates oyer 24 hour increased with increasing water temperature and the difference was the highest in 12L:12D. Oxygen consumption rate changed suddenly at dawn and at dusk.

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Endogenous Rhythms of $CO_2$ Assimilation, Stomatal Conductance and Soluble Carbohydrate Concentration during Grain Filling in Rice (벼 등숙기간중 $CO_2$ 동화율, 기공전도도 및 수용성 탄수화물 농도의 내생 리듬)

  • 현동윤
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.5
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    • pp.556-561
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    • 1995
  • Persisent circadian rhythms in carbon assimilation, stomatal conductance and soluble carbohydrate concentration were investigated during grain filling period in rice plant transferred from a natural photoperiod to constant conditions. A weak rhythm in photosynthesis, measured as carbon assimilation, and stomatal opening, as conductance to water vapor, with a period of approximately 24-hours, occurred under constant condition. Carbon assimilation and stomatal conductance reached maximum values near noon and minimum values near midnight during the early stage (until 72-hour) after transferring to constant condition, and then the amplitude and phase were changed slowly, the rhythms with little damping, reaching maximum values near midnight and minimum values near noon during 96~120-hours after transferring. However, photosynthesis in plants grown for 14days after anthesis under constant moderate light(day and night) did not oscillated in constant condition unlike plants grown under a cycle of light and darkness. These phenomenon was observed in soluble carbohydrate concentration in flag leaves as well. Evidences from several approaches indicate that endogenous rhythms of $CO_2$ assimilation, stomatal conductance and soluble carbohydrate concentration are closely couped with each other and particularly important to plants, which depend on the natural day-night cycle as a external signal.

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Effect of Photoperiod on Radiation-Induced Pink Mutations in Tradescantia Stamen Hairs (자주달개비 수술털에서 방사선에 의해 유발되는 분홍돌연변이에 대한 광주기의 영향)

  • 김원록;김진규
    • Korean Journal of Environmental Biology
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    • v.17 no.3
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    • pp.331-335
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    • 1999
  • The present study was carried out to investigate the combined effect of radiation and photoperiod (PP) regimes on Tradescantia 4430 somatic cell mutations. Potted plants were irradiated with 0.3, 0.5 and 1.0 Gy of gamma radiation from 60Co source. The plants irradiated only with gamma radiation were used as control group (CT). The somatic cell mutation rate in 0.5 Gy irradiated CT and PP20 group started to increase on the 6th day and reached a maximum value on the l0th day and 9th day after irradiation while the rate in the experimental group under 4 hours of photoperiod a day (PP4) started to increase on the l0th day and reached a maximal value on the 16th day post-irradiation. The slope of dose-response curve in CT was 5.99 ($r^2$=0.99), while it was 6.93 ($r^2$=0.98) in PP20 and 11.74 ($r^2$=0.99) in PP4, respectively. The biological efficacy of radiation in the induction of pink mutation increased by 15.7% in PP20 and 95.9 % in PP4, respectively. It is suggested that photoperiod regimes unfavorable to the plant have an additive effect on radiation-induced mutations and a delaying or inhibiting effect on cell damage repair, as well.

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Effect of Photoperiod Shortening on the Nutrient Uptake and Carbon Metabolism of Tomato and Hot Pepper Seedlings Grown Hydroponically (광주기 단축이 토마토와 고추 묘의 생장 및 무기양분흡수와 탄소대사에 미치는 영향)

  • Chi, Sung-Han
    • Journal of Bio-Environment Control
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    • v.12 no.3
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    • pp.121-126
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    • 2003
  • Tomato (Lycopersicon esculentum M. cv. ‘Momotarou’) and hot pepper seedlings (Capsicum annuum L. cv. 'Nockkwang')were grown under the 24h photopeliod (12 hrs light period: 12 hrs dark period) and 6 h photoperiod (3 hrs light period: 3hrs dark period). As a result of this experiment, the following details were observed. Plant height, leaf area, total dry weight, and leaf chlorophyll content decreased in case of tomato seedlings when they were given 6 h photoperiod. But the same effect was not observed in case of hot pepper seedlings. The photoperiod, however, did not produce any significant effect on the uptake of N, P, K, Mg and Ca ions in their nutrient solutions with the exception of their Fe. On thc 10th day of treatment, leaf chlorosis started to become visible in tomato seedlings and at the same time the uptake of Fe went down when the 6h photoperiod was applied to both tomato and hot pepper scedlings. In addition to this phenomenon, the sucrose content in leaf increased in case of tomato plants which were treated with 6 h photoperiod; on the other hand, their glucose content was observed to have decreased.