• Title/Summary/Keyword: Cool

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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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Ecological Studies on the Warm-Season Turfgrass and Cool-Season Turfgrass Mixtures (난지형 잔디와 한지형 잔디의 혼식에 관한 생태학적 연구)

  • Park, Bong-Ju
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.6 no.5
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    • pp.21-27
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    • 2003
  • Five warm-season turfgrass [Zoysia japonica Steud., Stenotaphrum secundatum (Walt.) Kuntze, Buchloe dactyloides (Nutt.) Engelm., Eremochloa ophiuroides (Munro.) Hack. and Cynodon dactylon (L.) Pers.] were overseeded with 2 cool-season turfgrasses [Poa pratensis L. and Festuca arundinacea Schreb.] to examine suitability of these species for planting in mixture for producing a year-round turf. Percent of warm-season and cool-season turfgrasses in the mixture were estimated for 5 years. Also, to evaluate the fertilization times of the warm-season and cool-season turrfgras mixtures. Eremochloa ophiuroides and Buchloe dactyloides were not suitable for warm-season and cool-season turfgrass mixtures. However, Zoysia japonica, Stenotaphrum secundatum and Cynodon dactylon were suitable for warm-season and cool-season turfgrass mixtures. Zoysia japonica, Stenotaphrum secundatum and Cynodon dactylon were showed approximately 50% botanical composition five years after cool-season turfgrass overseeding. And, those three warm-season turfgrass mixtures showed approximately 20% visual ratings in winter period. Fertilization in early spring and late autumn had made cool-season turfgrass dominated in mixtures. Therefore, fertilization times in warm-season and cool-season turfgrass mixtures was desirable in summer period.

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.

Design and Performance Test of a Direct Cooling Equipment for Hydrogen Liquefaction (수소액화용 직접냉각장치의 설계 및 성능시험)

  • Baik, Jong-Hoon;Kang, Byung-Ha;Chang, Ho-Myung
    • Transactions of the Korean hydrogen and new energy society
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    • v.7 no.2
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    • pp.121-128
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    • 1996
  • A direct cooling equipment for hydrogen liquefaction has been developed and tested. A direct cooling equipment consists of a liquefaction vessel, a radiation shield, a cryostat and a GM refrigerator. The cool-down and warm-up characteristics of the liquefaction apparatus have been investigated in detail. It is found that the hydrogen starts to be liquefied in the liquefaction vessel after 45 minutes of cool-down. The cool-down and warm-up tests of helium gas are also performed. The cool-down and warm-up characteristics of helium gas are found to be very different from those of hydrogen gas, since helium is not liquefied under the present operating conditions. When the liquefaction vessel is evacuated, natural convection phenomena of charged gas in liquefaction vessel can be removed. It is seen that the cool-down time of liquefaction vessel is substantially increased in vacuum environment.

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An Experimental Study on Heat Flow Characteristics of Inflowing Cool Air in the Room (실내(室內) 유입(流入) 냉기(冷氣)의 열유동(熱流動) 특성(特性)에 관한 실험적(實驗的) 연구(硏究))

  • Jang, Y.G.;Pak, J.W.;Pak, E.T.
    • Solar Energy
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    • v.18 no.1
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    • pp.57-67
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    • 1998
  • A study on a buoyancy effect by the temperature difference between a inner room air and a inflowing cool air and also by Inlet velocity can contribute greatly to enhance performance of air conditioning system, so the study on the distribution characteristics of inflowed cool air is important to analyze the cool air storage in a room. For this study, in the real-sized model room, the temperature differences between inflowing cool air and inner room air are 10, 20, $30^{\circ}C$, and the inlet velocities of inflowing cool air are 1, 2, 3m/s respectively as dynamic parameters. Also, a anemos and a vane type diffuser are used as inlet geometric conditions. Following conclusions have been obtained through this study. 1) In case of the anemos type diffuser, it is found that a dimensionless temperature profile is low and the distribution of the inflowed cool air is uniform. and also, all diffuusers have a low temperature of the inner room as increasing the inlet velocity. 2) A mixing takes place rapidly in case of the anemos type diffuser when the temperature difference is low ${\Delta}T=10^{\circ}C$ and the inletvelocity is high V=3m/s. and the mixing degree is higher with the anemos type diffuser than the vane.

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Subjective Wear Test and Fit of Women's Sports Underwear Made of Cool-Touch Fabric (냉감소재로 제작한 여성 스포츠 언더웨어의 피트성과 착용시 주관적 평가)

  • Kim, Soyoung;Lee, Heeran;Choi, Jiyoung;Hong, Kyunghi
    • The Korean Journal of Community Living Science
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    • v.28 no.4
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    • pp.505-514
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    • 2017
  • Although studies on the development of cool touch fabrics have been conducted widely, the effects of fitted pattern on enhancing the cooling sensation are insufficient. To investigate the effect of cool-touch fabric and fit of women's sports underwear, 3D and 2D patterns of sleeveless top and sports leggings were constructed. The performance of cool touch was tested by the Qmax value and wear test with nine subjects. Objective fit evaluation was observed by 3D virtual clothing using Clo software. Subjects rated wearing sensation such as 'cooling sensation, fit, wear comfort and preferences of purchase' using Likert's scale in the environmental chamber at $25^{\circ}C$, 45 %RH. The Qmax value of the cool touch fabric was higher than that of the PET fabric, which was well reflected in 'cooling sensation', especially in the case of a tight-fitted 3D pattern. The cooling sensation of the cool-touch fabric was not significantly elevated with 3D tight pattern as long as the size of the 2D pattern was similar to that of 3D pattern. However, the purchase preference was highly correlated with 3D fit and wear comfort.

Height Dependence of Plasma Properties in a Solar Limb Active Region Observed by Hinode/EIS

  • Lee, Kyoung-Sun;Imada, S.;Moon, Y.J.;Lee, Jin-Yi
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.110.2-110.2
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    • 2012
  • We investigate a cool loop and a dark lane over a limb active region on 2007 March 14 by the Hinode/EUV Imaging Spectrometer (EIS). The cool loop is clearly seen in the EIS spectral lines formed at the transition region temperature (log T = 5.8). The dark lane is characterized by an elongated faint structure in coronal spectral lines (log T = 5.8 - 6.1) and rooted on a bright point. We examine their electron densities, Doppler velocities, and non-thermal velocities as a function of distance from the limb using the spectral lines formed at different temperatures (log T = 5.4 - 6.4). The electron densities of the cool loop and the dark lane are derived from the density sensitive line pairs of Mg VII, Fe XII, and Fe XIV spectra. Under the hydrostatic equilibrium and isothermal assumption, we determine their temperatures from the density scale height. Comparing the scale height temperatures to the peak formation temperatures of the spectral lines, we note that the scale height temperature of the cool loop is consistent with a peak formation temperature of the Mg VII (log T = 5.8) and the scale height temperature of the dark lane is close to a peak formation temperature of the Fe XII and Fe XIII (log T = 6.1 - 6.2). It is interesting to note that the structures of the cool loop and the dark lane are most visible in these temperature lines. While the non-thermal velocity in the cool loop slightly decreases (less than 7 km $s^{-1}$) along the loop, that in the dark lane sharply falls off with height. The variation of non-thermal velocity with height in the cool loop and the dark lane is contrast to that in off-limb polar coronal holes which are considered as source of the fast solar wind. Such a decrease in the non-thermal velocity may be explained by wave damping near the solar surface or turbulence due to magnetic reconnection near the bright point.

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A Study on the Visual Evaluation for the combination of 'Clothing and Ground' (의복, 배경의 조합에 따른 시각적 이미지 연구(제2보))

  • 주소현;이경희
    • Journal of the Korean Society of Clothing and Textiles
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    • v.23 no.2
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    • pp.196-207
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    • 1999
  • The purpose of this study was to investigate the differences of the visual evaluation for the Picture image combination of Clothing and Ground. The major finding were as follows ; 1) For the visual evaluation of the Picture image as Clothing variation there were significant differences in all factors 2) For the visual evaluation of the Picture image as Ground variation there were significant differences in Attractiveness Hardness and softness Cuteness Attention Cool and Warm factor 3) For the visual evaluation of the Picture image as Percentage of Clothing there were significant differences in Attractiveness cool and Warm factor. It will Percentage of Clothing there were significant differences in Attractiveness Cool and Warm factor. It will aid in choosing the most beneficial background for any clothing brand. It will enhance the picture images to their full potential in any advertising medium 4) As a result of Regression analysis image effecting on " Preference" is refined-country like harmonious-inharmonious comfortable-uncomfortable beautiful-ugly splendid-dull stable-uneasy live-gentle 5) For the Image effecting on "Harmony" according to clothing image there were significant differences. the results analyzed according to the change of background are as follows. Mdern and strong images formed charming urban and cool visual images with urban and neat artificial backgrounds. Mature images were created with romantic and static artificial backgrounds. Mannish straight and conservative images created charming and rigid visual images in urban and formatted artificial background. Using a white natural background for the urban style created a cool visual image. The use of an interior background lead to warmer images and more defination lines Causal images created a rural and warm image which expressed charm and a soft visual while using a rural and natural background. A most unharmonious and hard image was created when using an urban and formatted artificial background. The coolest visual image was created with a cool and natural background. Feminine and flawless images created urban and neat visual image using an urban and formatted artificial background. The coolest visual image was fresh created with a cool and natural background. natural background.

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Effect of Collection Seasons on the Oocyte Quality and Developmental Competence of Oocytes Derived from Korean Native Cows (Hanwoo) by Ovum Pick-Up (OPU 채란계절이 한우의 난자 품질 및 발달 능력에 미치는 영향)

  • Kim, Seong-Su;Choi, Byung Hyun;Jo, Hyun-Tae;Jin, Jong-In;Ha, A-Na;Min, Chan-Sik;Cho, Gyu-Wan;Kong, Il-Keun
    • Journal of Embryo Transfer
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    • v.29 no.3
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    • pp.265-271
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    • 2014
  • Implementation of smart embryo technologies in cattle e.g. ovum pick-up followed by in vitro embryo production (OPU-IVP). Seasonal variation is important factor for follicular growth, oocytes quality, quantity and developmental competence. Therefore the aim of present study was carried out to investigated whether the seasons (hot and cool) effect on follicular development, oocyte recovery and subsequent embryo development. Follicular oocytes were aspirated from Korean native cows (Hanwoo) by the ovum pick-up (OPU) method, which was performed 24 times during two different seasons, the hot (July to September) and cool (October to December), from OPU donors. The recovered oocytes were classified according to morphological categories and used for in vitro embryo production (IVEP). The mean number of total follicles was significantly higher (p<0.05) during the hot season ($18.32{\pm}2.26$) compared to cool season ($15.41{\pm}3.34$). Furthermore, seasons did not significantly effect on the number of oocytes recovered (hot season: 41.16% vs. cool season: 46.14%). However, the average number of Grade A oocytes was significantly greater during hot ($1.75{\pm}1.86$) season compared to the cool season ($1.00{\pm}1.46$), but there was no significant difference of other grades oocytes. The cleavage rate (hot: 66.67% vs. cool: 63.3%) and embryo development (hot: 58.95% vs. cool: 56.97%) did not differ significantly between the seasons. In conclusion, the results of present study suggest that the season (hot and cool) does not have effects on the oocyte recovery and embryo developmental competence of in vitro cultured embryos.

A Study on Information Asymmetry and the Country of Origin Labeling in Live Small Fish Trade for Aquaculture and Naturalization (이식용수산물 교역의 정보비대칭과 원산지표시제도 영향에 관한 연구)

  • Park Seong-Kwae;Han Kyung-Sook
    • The Journal of Fisheries Business Administration
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    • v.37 no.1 s.70
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    • pp.45-71
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    • 2006
  • The main objective of this study is to analyze problems of the Country of Origin Labeling(COOL) in small live fish(SLF) trade by applying the asymmetric information theory which is called ${\ulcorner}$Lemon Market Theory${\lrcorner}$. The purpose of importing SLF is to enhance fishing household income and import substitution effect as well. SLF importation is quite different in its nature from importing general fish and fish products for final/direct consumption. SLF are imported for the purpose of domestic aquaculture and naturalization where domestic production/supply of SLF is less than domestic demand for or such species are not native to Korean waters. Information asymmetric problems arise even in SLF trade as the same way in general goods and services. However, the information asymmetry issues in SLF trade are much more complex than non-living goods because SLF are traded in the live state. To alleviate such problems the Korean government initiated the general COOL scheme to imported SLF. However, many experts argues that such policy on SLF would not be appropriate because of SLF's very nature. Applying the lemon market theory, we can analyze how information discovery schemes are able to signal correct information to SLF trading parties and to result in more symmetric information in SLF trade markets. This research carried out a case study about small live eel(SLF) trade and its farming. The results showed that applying the COOL to small live eels just right upon coming into fish farms tends to increase substantially fish farmer's income and at the same time to lower unnecessary transaction costs. In particular, such transaction costs by imposing simply the general COOL on SLF may easily outweigh its benefits. For instance, to resolve the problems, the Korean ministry of agriculture and forestry(KMAF) has developed a quite different COOL rules from the general ones and has applied them to imported live cattle and medium/small livestocks. The KMAF's differentiated COOL policy on some imported livestocks may be a good case which can be applied to imported SLF. In addition to the differentiated COOL on SLF, Sanitary and Phytosanitary (SPS) and traceability system would play crucial complementary roles in alleviating information asymmetry problems in SLF trade. Advanced fisheries tend to strengthen their SPS system rather than to adopt the general comprehensive COOL schemes into imported SLF trades and domestic market exchanges.

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