• Title/Summary/Keyword: Temperature Lift

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Distribution of Anchovy School catched by the lift Net and Environmental Factors in the Kamak Bay 1. Relation between distribution of the Anchovy School and Temperature and salinity (가막만에서의 멸치 들망 어장의 분포.이동과 환경 요인의 관계 1.수온.연분과 어군의 분포)

  • 서영준
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.35 no.3
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    • pp.267-276
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    • 1999
  • In order to investigate the properties in distribution and movement of anchovy school catches by the lift net in the Kamak bay and their relation to the environmental factors, i.e., the water temperature and the salinity were observed form June to August in 1997 and compared with the catch of anchovy by the lift net. The results obtained are summarized as follows;1) The water temperature and salinity ranged form 20.0 to $27.0^{\circ}C\;and\;from\;31.2\;to\;33.8\texperthousand$, respectively. The water temperature and salinity at the fishing points ranged form 19.7 to $27.2^{\circ}C\;and,\;from\;30.5\;to\;33.8^{\circ}C$ respectively.2) The water temperature influenced remarkably on the distribution and movement of anchovy school. But the salinity influenced little on the distribution and movement. 3) The catch of anchovy was highest on July, poor second on August, and lowest on June. Anchovy school can be presurmed, they are come from north of bay, visited and distributed through east of bay at the middle of June. Moreover, they spreaded in all bay. Then gradually, when July arrive, they go to the south th nearest the coasts, and they are outflow through the south entrance of bay at the end of August.

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A Study on the Durability Characteristics of an Air-lubricated Bump Foil Journal Bearing (공기윤활 범프포일 저널 베어링의 내구성 특성에 관한 연구)

  • 이용복;김태호;김창호;이남수;장건희
    • Tribology and Lubricants
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    • v.18 no.2
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    • pp.153-159
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    • 2002
  • This paper describes a durability characteristics of an air-lubricated bump foil journal bearing for high speed turbomachinerys at room temperature. At first, lift-off test and load capacity test were performed to understand the general characteristics of an air-lubricated bump foil Journal bearing. A 52 N weighted bump foil bearing sleeve was lilted off from a rotating Journal at about 3,000 rpm, and produced a load capacity of 500 N at an operating speed of 15,000 rpm. The next was 500 cycles lift-off test with an air-lubricated bump foil journal bearing that had a molybdenum disulfide(MoS$_2$) solid lubricant coated top foil. Data from measuring bearing torque and temperature and the observation of rubbing surfAce were included in results. Therefore the results of this work will aid in proving durability of air-lubricated bump foil journal bearings.

A Study on the Durability Characteristics of an Air-lubricated Bump Foil Journal Bearing (공기윤활 범프포일 저널 베어링의 내구성 특성에 관한 연구)

  • 김태호;이용복;김창호;이남수;장건희
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2001.11a
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    • pp.212-219
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    • 2001
  • This paper describes a durability characteristics of an air-lubricated bump foil journal bearing for high speed turbomachinerys at room temperature. At first, lift-off test and load capacity test were performed to understand the general characteristics of an air-lubricated bump foil journal bearing. A 52N weighted bump foil bearing sleeve was lifted off from a rotating journal at about 3,000rpm, and produced a load capacity of 500N at an operating speed of 15,000rpm. The next was 500 cycles lift-off test with an air-lubricated bump foil journal bearing that had a molybdenum disulfide(MoS$_2$) solid lubricant coated top foil. Data from measuring bearing torque and temperature and the observation of rubbing surface were included in results. Therefore the results of this work will aid in proving durability of air-lubricated bump foil journal bearings.

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Exopolysaccharide Production and Mycelial Growth in an Air-Lift Bioreactor Using Fomitopsis pinicola

  • Choi, Du-Bok;Maeng, Jeung-Moo;Ding, Ji-Lu;Cha, Wol-Suk
    • Journal of Microbiology and Biotechnology
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    • v.17 no.8
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    • pp.1369-1378
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    • 2007
  • For effective exopolysaccharide production and mycelial growth by a liquid culture of Fomitopsis pinicola in an air-lift bioreactor, the culture temperature, pH, carbon source, nitrogen source, and mineral source were initially investigated in a flask. The optimal temperature and pH for mycelial growth and exopolysaccharide production were $25^{\circ}C$ and 6.0, respectively. Among the various carbon sources tested, glucose was found to be the most suitable carbon source. In particular, the maximum mycelial growth and exopolysaccharide production were achieved in 4% glucose. The best nitrogen sources were yeast extract and malt extract. The optimal concentrations of yeast extract and malt extract were 0.5 and 0.1%, respectively. $K_2HPO_4\;and\;MgSO_4{\cdot}7H_2O$ were found to be the best mineral sources for mycelial growth and exopolysaccharide production. In order to investigate the effect of aeration on mycelial growth and exopolysaccharide production in an air-lift bioreactor, various aerations were tested for 8 days. The maximum mycelial growth and exopolysaccharide production were 7.9 g/l and 2.6 g/l, respectively, at 1.5 vvm of aeration. In addition, a batch culture in an air-lift bioreactor was carried out for 11 days under the optimal conditions. The maximum mycelial growth was 10.4 g/l, which was approximately 1.7-fold higher than that of basal medium. The exopolysaccharide production was increased with increased culture time. The maximum concentration of exopolysaccharide was 4.4 g/l, which was about 3.3-fold higher than that of basal medium. These results indicate that exopolysaccharide production increased in parallel with the growth of mycelium, and also show that product formation is associated with mycelial growth. The developed model in an air-lift bioreactor showed good agreement with experimental data and simulated results on mycelial growth and exopolysaccharide production in the culture of F. pinicola.

Themodynamic Characteristics of a Two-Stage Binary Absorption Cycle (2단(段) 2원(元) 흡수(吸收)사이클의 특성(特性)에 관(關)한 연구(硏究))

  • Lee, Y.H.;Rie, D.H.;Kashiwagi, T.;Seo, J.Y.
    • Solar Energy
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    • v.15 no.1
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    • pp.29-38
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    • 1995
  • This paper concerns the study of a two-stage binary absorption cycle employing the refrigerant/absorbent combinations of $LiBr/H_2O$ and $NH_3/H_2O$. This cycle consists of coupling two single-effect absorption cycles so that the first stage absorber and condenser produces heating water to evaporate refrigerant in the evaporator of the second stage. The effect of operating variables such as evaporator temperature, condenser and absorber temperature, and generator temperature on the coefficient of performance and temperature lift have been studied for two-stage binary absorption heat pump systems. It is found that this cycle has a large temperature lift at $105^{\circ}C$ of optimum generator temperature to obtain $50^{\circ}C$ of condenser temperature.

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A Study on Applicability of Air-lift Pump for Deep Seawater pumping (해양심층수 취수를 위한 기포펌프의 적용성 연구)

  • Shin P. K.;Kim H J.;Hong S. W.;Choin H S.
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2004.11a
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    • pp.13-16
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    • 2004
  • Deep sea water has mid temperature, abundant nutrients and minerals, and good tooter quality. For the purpose of drawing up deep sea water without pump pit construction, tile authors are considering to use air-lift pump. This report describes fundamental experimental investigation for air-lift pump characteristic and improvement in efficiency.

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Hydrogenotrophic Sulfate Reduction in a Gas-Lift Bioreactor Operated at $9^{\circ}C$

  • Nevatalo, Laura M.;Bijmans, Martijn F. M.;Lens, Piet N. L.;Kaksonen, Anna H.;Puhakka, Jaakko A.
    • Journal of Microbiology and Biotechnology
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    • v.20 no.3
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    • pp.615-621
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    • 2010
  • The viability of low-temperature sulfate reduction with hydrogen as electron donor was studied with a bench-scale gas-lift bioreactor (GLB) operated at $9^{\circ}C$. Prior to the GLB experiment, the temperature range of sulfate reduction of the inoculum was assayed. The results of the temperature gradient assay indicated that the inoculum was a psychrotolerant mesophilic enrichment culture that had an optimal temperature for sulfate reduction of $31^{\circ}C$, and minimum and maximum temperatures of $7^{\circ}C$ and $41^{\circ}C$, respectively. In the GLB experiment at $9^{\circ}C$, a sulfate reduction rate of 500-600 mg $l^{-1}d^{-1}$, corresponding to a specific activity of 173 mg ${SO_4}^{2-}g\;VSS^{-1}d^{-1}$, was obtained. The electron flow from the consumed $H_2$-gas to sulfate reduction varied between 27% and 52%, whereas the electron flow to acetate production decreased steadily from 15% to 5%. No methane was produced. Acetate was produced from $CO_2$ and $H_2$ by homoacetogenic bacteria. Acetate supported the growth of some heterotrophic sulfate-reducing bacteria. The sulfate reduction rate in the GLB was limited by the slow biomass growth rate at $9^{\circ}C$ and low biomass retention in the reactor. Nevertheless, this study demonstrated the potential sulfate reduction rate of psychrotolerant sulfate-reducing mesophiles at suboptimal temperature.

Environmental Condition of Sea Areas for Anchovy Lift Net in Kamak Bay (가막만 멸치 들망 어장의 해역별 특성)

  • Lee, In-Weon;Kim, Dong-Soo
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.34 no.1
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    • pp.67-73
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    • 1998
  • In order to find out the environmental factors influencing the catch of anchovy lift nets in kamakbay, the three oceanographic factors, i. e., the water temperature, the salinity, the amount of chlorophyll-a were observed respectively from August 1 to 12, 1995 and from September 20 to 26, 1995, and each of them was compared with the catch of anchovy by the lift net. The results obtained are summerized as follow : 1) The water temperature was ranged from 17.3 to 29.6$^{\circ}C$ and its difference between the surface and bottom was 1 to 3$^{\circ}C$. In the three areas, A, B and C, the area A was the hightest in temperature, the area B being a second, and the area C being the lowest. 2) The salinity was ranged from 32.20 to 33.47$\textperthousand$ and its difference between the surface and bottom was not significant. In the three areas, the area A was the highest in salinity, the area B being a second, and the area C being the lowest. 3) The amount of chlorophyll-a was ranged from 0.19 to 5.30mg/m supper(3) and its difference among the three areas was not significant. Daily variation of the amount was very irregulated because the position operated was changed daily. 4) A comparison of the water temperature, the salinity and the amount of chlorophyll-a with the catch gave that the water temperature and the amount of chlorophyll-a had large influence on the catch and the salinity did not so. However, the influence of the amount of chlorophyll-a was larger than that of the water temperature. 5) The catch of anchovy was large respectively during two hours after sun set and during two hours before sun rise.

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Development of Single effect/Double lift Absorption Chiller & Heater for a District Heating Net work (저온수2단흡수냉난방기의 개발)

  • Koo, Ki-Dong;Kim, Sang-Ho;Ryu, Jin-Sang;Lee, Jae-Young;Seo, Jong-Cheol;Jang, Hoon
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.668-672
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    • 2009
  • This is to report the result of Development of Single effect/Double lift absorption chiller & heater which is used in the district heating net work. The heating cycle was newly developed to make the secondary hot water from evaporator and the cycle change-over function was added for the heating to the cooling mode and the cooling to the heating mode. Finally, it was assured through the site trial operation that the outlet temperature of primary hot water can be produced lower than $68^{\circ}C$ when the outlet temperature of secondary hot water is $60^{\circ}C$.

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Design of Automotive Anti-trap Power Window Lift Controller (자동차 Anti-trap Power Window Lift Controller 설계)

  • Cha, Min-Hyeok;Kim, Hak-Lyun;Lee, Ju
    • Proceedings of the KIEE Conference
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    • 2001.10a
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    • pp.51-53
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    • 2001
  • Permanent Magnet DC Motors are widely used in Automotive parts because they have cheap price, simple structure and high torque-speed ratio. But the motor in automotive parts is required high quality, complex function and lower price than before. This paper deals with design of controller for safety function that body trap on the automotive window. The algorithm of controller can adapt variety conditions with temperature, electrical, driving, etc.

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