• Title/Summary/Keyword: Cool Water

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Effect of Cool Drinking Water on Production and Shell Quality of Laying Hens in Summer

  • Glatz, P.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.6
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    • pp.850-854
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    • 2001
  • Feed intake, egg weight, rate of lay and shell quality characteristics were measured in an Australian tinted egg laying strain from 31-42 weeks of age, housed at $30^{\circ}C$ and provided drinking water at 5, 10, 17 and $30^{\circ}C$. In a second experiment a European brown egg laying strain (59-66 weeks of age) housed at $30^{\circ}C$ were provided drinking water at 5, 10, 15 and $30^{\circ}C$. Brown egg layers given cool drinking water (5, 10 and $15^{\circ}C$) consumed more (p<0.05) feed and produced significantly (p<0.05) thicker and heavier shells than hens given drinking water at ambient temperature ($30^{\circ}C$). However the tinted egg layers given chilled drinking water only consumed more (p<0.05) feed and produced thicker (p<0.05) and heavier (p<0.05) shells when consuming drinking water at $5^{\circ}C$. As the tinted egg layers acclimatised to the environmental temperature there was a decline in the influence of cool drinking water on feed intake and shell quality. For brown egg layers, however, cool drinking water resulted in an improvement (p<0.05) in feed intake and shell quality over the entire period birds were provided cool water. These studies suggest that there is potential for using cool drinking water to improve feed intake and shell quality of hens housed under hot conditions. The combination of high ambient temperature and high drinking water temperature, a common occurrence in Australian layer sheds, should be avoided.

Comparative Evaluation of Cool Surface Ratio in University Campus: A Case Study of KNU and UC Davis (대학 캠퍼스의 쿨표면 비율 비교평가: 경북대학교와 UC Davis를 사례로)

  • Hwang, Young-Seok;Um, Jung-Sup
    • KIEAE Journal
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    • v.15 no.1
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    • pp.117-127
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    • 2015
  • The cool surface ratio could be used as a proxy of the overall thermal environment contributing to heat islands in urban area. This research proposes a comparative evaluation framework in an objective and quantitative way for measuring cool surface ratios. Two university campuses (Kyungpook National University: KNU, South Korea and UC Davis: University of California, Davis, USA) were selected as case study sites in order to monitor cool surface condition. Google Earth combined with digital maps realistically identified the major type of cool surfaces such as cool roofs and water bodies in the study area. Cool surfaces were sparsely identified over the KNU campus while the UC Davis campus was heavily covered by cool surfaces such as cool roofs and water bodies, resulting in almost four times more first-grade cool surfaces, as compared to KNU. It is confirmed that standard remote sensing technology can offer the viable method of measuring and comparing the campus-wide cool surface condition. It is anticipated that this research output could be used as a valuable reference to initiate a nation-wide cool surface strategy since objective evidence has been provided based on area-wide measurement for the cool surface in the two university context.

DEVELOPMENT OF NIGHT COOLING SYSTEM FOR GREENHOUSE USING COOL AIR AND WATER FROM AN ABANDONED COAL MINE

  • Whoa S. Kang;Wie S. Kang;Lee, Gwi H.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1996.06c
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    • pp.1136-1145
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    • 1996
  • This study was to develop the most effective cooling system which is needed to cool greenhouse during summer night to get early blooming of strawberries. Various cooling systems were designed and constructed to utilize the cool air and water from tan abandoned coal mine. Cooling systems built for this study were an evaporative cooling system with pad, cooling system using a small or large radiator , and duct cooling system using cool are drawn from coal mine. These systems were individual tested to investigate their effects on cooling greenhouse during summer night. Also, a combined cooling system was tested with operating an evaporative cooling system, small radiator, and duct cooling system simultaneously. The results in this study showed that individual cooling systems such as evaporative cooling system, small radiator, and cooling duct had about the same effect on cooling greenhouse. The combined system had little better cooling effect than that of individual cooling syst m except the large radiator . The most effective system for cooling of greenhouse was obtained with using a large a large radiator as the heat exchanger. With operating a large radiator, temperature inside the greenhouse was dropped to about 15-16$^{\circ}C$ while outside temperature was 23-24$^{\circ}C$ during summer night.

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농업용수의 수온 상승에 관한 연구

  • Hwang, Eun;Kim, Cheol-Gyu;Lee, Sang-Beom
    • Water for future
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    • v.5 no.2
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    • pp.17-29
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    • 1972
  • The persent study aims at finding out a means of prevention cool spell damages on the hilly areas. The irrigation plots of 24 hour stored water warm water way and warm water plots, cool water way are respectively established to find out water temperature and influnce on the growing rice plants. The results obtained are summed up as follows. 1. Warm water areas consisted of $5 m^2 Q=0.93 1{\ell}/sec$, V=31 cm/sec, S=1/1, 000, L=81.6m, B=5cm, h=6cm, t=4min 33sec, drops=9 areas, are constructed to help the water temperature of $14.5^{\circ}C$ rise to that of $21.6^{\circ}C$. This indicates lower temperature than $23^{\circ}C$ of critical water temperature in irrigation facilities by $1.45^{\circ}C$ and than $26.2^{\circ}C$ of balanced water temperature of Seoul arears by $4.6^{\circ}C$. But this does not give much influance on rice plant cultivation. 2. The rising of water temperature is influened according to the temperature, solar radiation but the water temperature changes according to the heat absorption of organized materials, weather and terraces. The difference of water temperature could be found in the first growing stage. 3. Through the warm water way of water rises to the temperature of $21.6^{\circ}C$ which also rises to the temperature of around $30^{\circ}C$ in the paddy field of submerged irrigation. The rice plants are comparatively free from prolonged cool damage, reproduction abstructive damage. 4. The water temperature in rice field in proportion to temperature influence of weather condition but the water temperature approaches to that of weather in the days of later growing stage and water temperature become lower than the air temperature in the fruit stage. 5. The water in the submreged field is $10^{\circ}C$ warmer than in the warm water way during the first growing stage period but the water temperature in the warm water way is warmer in the later growing stage period. The cool water of $14.5^{\circ}C$ is warmed to $30.1^{\circ}C$ and rice plants cultivation is free from other damages. 6. The 12% increased production or 570.98kg/10a is made cool water plot by rising the temperature of water from $14.5^{\circ}C$ to $21.6^{\circ}C$ making the water run through warm water way. 7. The damage inflicted by the cool water irrigation during the first growing stage period is the obstruction of peak tillering stage and the obstruction of heading the later growing stage period and the obstruction of fruiting and number of panides per fill.

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Ablation Characteristics of Bovine Liver According to Cool-Tip Temperature of RFA Equipment (고주파 열치료 장비의 Cool-Tip 온도에 따른 소간의 소작 특성)

  • Choi, Young-Jae;Kim, Jeong-Koo
    • Journal of radiological science and technology
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    • v.38 no.2
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    • pp.155-161
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    • 2015
  • This study confirmed the correlation between the change of the cooling water in internal cooling system and the size of the ablation site of bovine liver in RF heat treatment equipment. The bovine liver was resection with $4{\times}4{\times}4cm^3$ in 2cm cool-tip and with $6{\times}6{\times}6cm^3$ in 3cm cool-tip for the experiments. Area and perimeter of the ablation site for bovine liver were measured by Freehand techniques of MRI. It showed area and perimeter decreased during cool-tip temperature rises 6 and 12 minutes ablation using a 2cm and 3cm cool-tip. The correlation of cool-tip temperature and area and perimeter was statistically significant the result are shown(p=.000). The measurements of area and perimeter were more accurate with MRI in actual measurements and MRI for ablation range. The statistical results using Paired sample T-test was also significant(p=.038). The ablation range of bovine liver decreased according as cooling water temperature increases in RF heat treatment equipment for reason of carbonization occurred due to does not accurately pass the RF energy. Therefore, it is considered the effect of RF heat treatment would be increased if the temperature of the cooling water consistently maintain the low temperature in order to reduce the generation of carbide at RF heat treatment and RF energy is delivered accurately.

Physical Properties of Soil and Turfgrass Wear Characteristics of Soccer Fields - A Simulation of the Inchon 2002 World Cup Stadium - (축구경기장 토양의 물리적 특성과 잔디 마모특성 - 2002년 월드컵 인천경기장 모형돔을 대상으로 -)

  • 심상렬;정대영
    • Journal of the Korean Institute of Landscape Architecture
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    • v.30 no.1
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    • pp.96-104
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    • 2002
  • This study was conducted to investigate physical properties of soil and turfgrass wear characteristics within turfgrasses inside or outside the stadium A 1/1000 scale model Inchon world cup soccer d[me was constructed for this test. Turfgrasses planted inside and outside the model dome were; Kentucky bluegrass(KB), Kentucky bluegrass + perennial ryegrass mixture (KB+PR), Kentucky bluegrass + tall fescue + perennial ryegrass mixture (KB+TF+PR), Zoysia japonica 'Anyangjungzii'(ZA) and Zoysia japonica 'Zenith\`(ZZ). The rootzone was constructed by the multi-layer method (United States Golf Association method). Traffic on turfgrasses was treated with a 120kg roller. Surface soil hardness, soil penetration and water infiltration values on cool-season grasses(KB, KB+PR, KB+TF+PR) was found to be better for soccer play compared to zoysiagrasses(ZA, ZZ). No big differences in surface soil hardness, soil penetration and water infiltration values were found between inside and outside of the model dome. Wear damage on cool-season grasses caused by the traffic treatment was low compared to zoysiagrasses. However, there was no difference in wear damage by the traffic treatment within cool-season grasses while wear damage on ZA was higher than on ZZ within zoysiagrasses. It could be concluded that physical properties and wear characteristics on cool-season grasses were much better for soccer play than on zoysiagrasses.

Probabilistic Fracture Mechanics Analysis of Boling Water Reactor Vessel for Cool-Down and Low Temperature Over-Pressurization Transients

  • Park, Jeong Soon;Choi, Young Hwan;Jhung, Myung Jo
    • Nuclear Engineering and Technology
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    • v.48 no.2
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    • pp.545-553
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    • 2016
  • The failure probabilities of the reactor pressure vessel (RPV) for low temperature over-pressurization (LTOP) and cool-down transients are calculated in this study. For the cool-down transient, a pressure-temperature limit curve is generated in accordance with Section XI, Appendix G of the American Society of Mechanical Engineers (ASME) code, from which safety margin factors are deliberately removed for the probabilistic fracture mechanics analysis. Then, sensitivity analyses are conducted to understand the effects of some input parameters. For the LTOP transient, the failure of the RPV mostly occurs during the period of the abrupt pressure rise. For the cool-down transient, the decrease of the fracture toughness with temperature and time plays a main role in RPV failure at the end of the cool-down process. As expected, the failure probability increases with increasing fluence, Cu and Ni contents, and initial reference temperature-nil ductility transition ($RT_{NDT}$). The effect of warm prestressing on the vessel failure probability for LTOP is not significant because most of the failures happen before the stress intensity factor reaches the peak value while its effect reduces the failure probability by more than one order of magnitude for the cool-down transient.

Long-term Ecological Research Programme in Forestry Research Institute, Korea

  • Oh, Jeong-Soo;Shin, Joon-Hwan;Lim, Jong-Hwan
    • The Korean Journal of Ecology
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    • v.23 no.2
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    • pp.131-134
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    • 2000
  • Forest vegetation in Korea can be largely divided into warm temperate, cool temperate and frigid forest zone. The cool temperate forest zone of them occupies the largest part of the Korean peninsula and it is generally divided into three subdivisions such as northern, central and southern subzone. The Forestry Research Institute established three long-term ecological research sites at Kwangnung Experiment Forest in the central subzone of the cool temperate forest zone, at the Mt. Kyebangsan Forest in the northern subzone of the cool temperate forest zone. and at the Mt. Keumsan Forest in the warm temperate forest zone. The objectives of long-term ecological research in the Forestry Research Institute, Korea are to study long-term changes of the forest ecosystems in energy fluxes, water and nutrient cycling, forest stand structure, biological diversity, to quantify nutrient budgets and fluxes among forest ecosystem compartments and to integrate ecological data with a GIS - assisted model. To achieve the objectives, forest stand dynamics. environmental changes in soil properties, stream water quality, nutrient cycling, air pollution and biological diversity have been investigated and plant phonology as an indicator of climate change has been monitored in the LTER sites.

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Experimental Study on Performance Characteristics of Liquid Rocket Engine (액체로켓엔진의 성능특성 연구)

  • 장행수;이성웅;조용호;우유철
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2003.05a
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    • pp.211-217
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    • 2003
  • A liquid rocket engine(LRE) Using LO$_2$/LNG(Liquefied Natural Gas) propellants was experimentally evaluated. The purpose of this study was to investigate the performance of the LO$_2$/LNG rocket combustor that is composed of three sect ions(igniter spacer, cylinder and nozzle section), especially focused on the influence of regenerative cool ing effect in association with the phase of regenerative coolant Series of tests were conducted under the conditions of water cool ing and regenerative cool ing with LNG in the cylinder section and independent cool ing with water in the igniter spacer and nozzle sections. Parametric studies on the variation of a chamber pressure and mixture ratio were undertaken. In addition, effect of propellant(LNG) composition and its enthalpy on the performance is examined.

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An Experimental Study on the Performance of Cool Storage System using R141b Clathrate (R141b 포접화합물을 이용한 축냉시스템의 성능에 관한 실험적 연구)

  • Jung, I.S.;Kim, Y.G.;Lee, J.S.;Ro, S.T.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.6 no.4
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    • pp.354-364
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    • 1994
  • Experiments have carried out to investigate the effects of parameters, such as mass ratio of R141b-to-water, stirrer speed, brine inlet temperature, brine flowrate, and additives, on the performance of the cool storage system using R141b clathrate. The cool storage system in this experiment was composed of storage tank, refrigerator, and heater. The results show that the mass ratio of R141b-to-water, 1 : 3~1 : 3.5 gives the best performance and the stirring speed has optimum point as 600rpm. At this speed impeller Reynolds number is $1.01{\times}10^5$. The lower the inlet brine temperature and the highter the brine flowrate, the better performance. The addition of metal powder turned out to reduce the degree of supercooling. The supercooling reduction was proportional to the amount of the metal power. However when metal powder was added more than 0.1 wt%, there was no additional supercooling reduction. The surfactants shortened the time consumed for cool storage to the half of no surfactant added case.

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