• Title/Summary/Keyword: 보온율

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Estimation of Heat Insulation and Light Transmission Performance According to Covering Methods of Plastic Greenhouses (플라스틱온실의 피복방식에 따른 보온 및 광투과 성능 평가)

  • Lee, Hyun-Woo;Kim, Young-Shik;Sim, Sang-Youn;Lee, Jong-Won;Diop, Souleymane
    • Journal of Bio-Environment Control
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    • v.22 no.3
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    • pp.270-278
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    • 2013
  • The objective of the present study is to provide data needed to decide covering method to be able to increase the thermal insulation and light transmittance efficiency of commercial greenhouse. The thermal insulation effect, PPF transmittance and quantity of condensation water were estimated in experimental tomato greenhouses covered with three types of coverings of single layer, air inflated and conventional double layers covering. The overall heat flow of air inflated double layers greenhouse was similar to that of conventional double layers greenhouse, but the temperature between covering material and thermal screen in air inflated double layers greenhouse was lower than that in conventional double layers greenhouse at the same outside temperature condition due to air leakage through the gap of roof vent. The overall heat transfer coefficients acquired by experiment that was performed in single layer and conventional double layers greenhouses were close to those obtained from model experiment. Even though the PPF transmittance of air inflated double layers greenhouse was lower than that of single layer greenhouse, which was greater than that of conventional double layers greenhouse. The quantity of condensation water on covering surface of single layer greenhouse was greater than that of air inflated double layers greenhouse due to lower covering surface temperature.

Evaluation of the Reaction-to-fire Performance of Pipe Insulation Material using Small Room Test (룸코너 시험을 이용한 배관용 보온재의 난연성능 분석)

  • Lim, Ohk Kun;Nam, Dong-gun;Jang, Hyo-Yeon
    • Fire Science and Engineering
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    • v.33 no.4
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    • pp.1-8
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    • 2019
  • Reaction-to-fire performance of pipe insulation materials should be approved in accordance with KS standards prior to installing water-based suppression systems because several fire accidents are initiated from insulation materials around ceilings or concealed space. A small room test to evaluate the reaction-to-fire performance of the polyethylene foam and elastomeric pipe insulation materials was conducted according to ISO 20632. Different fire growth rate and heat release rate are observed depending on the materials and construction methods. In order to improve a fire safety, the reaction-to-fire performance of pipe insulation material needs to be subdivided with regard to the heat release rate and smoke generation. Furthermore, the characteristics of the applying space are also required to be considered. Subsidiary materials for installation process such as tape and adhesive are found to provide an adverse effect to maintain a fire safety.

A Study on the Thermal Comfort to the Weight Reduction Rate and Fabric Structural Parameters of PET Fabrics (PET직물의 감량율과 직물구조인자에 따른 열적 쾌적성 변화에 관한 연구)

  • 이희준;이민수;김승진;조대현;김태훈
    • Journal of the Korean Society of Clothing and Textiles
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    • v.22 no.7
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    • pp.816-825
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    • 1998
  • This study surveys the thermal property and air permeability to the weight reduction rate of PET fabrics. For this purpose, 12 kinds of satin and 18 kinds of plain weave fabrics are prepared with change of the physical properties such as weft yarn count, t.p.m. and density. The weight reduction rate was 0%, 12%, 25% and 30%. The warm/cool feeling(Qmax), thermal insulating value(T.I.V.) and thermal conductivity(K) were measured by KES-F7 System and discussed in relation with the weight reduction rate, weft yarn linear density, t.p.m., weft density of fabric and weave structure.

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Evaluation of Thermal Insulation Properties of Covering Materials to Protect Peach Trunks against Freezing Injury (복숭아 주간부 동해 예방을 위한 피복재의 보온성 평가)

  • Shin, Hyunsuk;Yun, Seok Kyu;Choi, In Myung;Kim, Sung Jong;Yun, Ik Koo;Nam, Eun Young;Kwon, Jung Hyun
    • Journal of Bio-Environment Control
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    • v.25 no.4
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    • pp.288-293
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    • 2016
  • The study was performed to evaluate thermal insulation covering materials (TICMs) to protect peach trunks against freezing temperatures in winter season by investigating thermo-physical properties and practical thermal insulation effect of the TICMs which was made of white non-woven fabrics, yellow paper sheets, and waterproof fabric pads. Among the three TICMs, Waterproof fabric pad (double layer) possessed the best performance about thermal insulation rate and thermal resistance among three kinds of TICMs. Day thermal insulation effects of waterproof fabric pad, which prevent from temperature rise on the bark tissues of trunks during the day time, were $14.09^{\circ}C$. Night thermal insulation effects of them, which prevent from temperature decline on the bark tissues of trunks at night time, were $7.23^{\circ}C$. Waterproof fabric pad showed the highest day and night thermal insulation effects. Thus our results suggest that development of TICMs using waterproof fabric pad might be helpful to protect the bark tissues of trunks from freezing injury.

The Differences of Temperatures, Growth and Crown Gall Occurrence in Young 'Kyoho' Grapevines According to Heat Conservation Materials during Winter (보온피복재 종류가 '거봉' 포도 유목의 월동시 온도 차이, 발아 및 근두암종병 발생에 미치는 영향)

  • Nam, Sang-Young;Kim, Seon-Kyu;Kim, Kyoung-Mi;Jung, Jai-Hyun;Choi, Kwan-Soon
    • Horticultural Science & Technology
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    • v.16 no.4
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    • pp.517-519
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    • 1998
  • This experiment was carried out to find out the effects of heat conservation materials (burying in soil, lagging, lagging +straw, nonwoven fabric, nonwoven fabric+straw) on freezing damage, labor saving, and crown gall occurrence of 'Kyoho' grapes. Temperature differences in burying in soil and lagging with $2.8^{\circ}C$ and $6.4^{\circ}C$, respectively and were considered favorable for over-wintering of grapevines. Heat conservation index in lagging +straw and burying in soil calculated from degree-hours below $-10^{\circ}C$ was 5 to 7 times higher than that of open field. Budbreak started earlier in lagging with+straw and nonwoven fabric+straw covering, and percent budbreak was increased by 22% and 7%, respectively, as well as higher than burying in soil. Diameter of bearing mother branch and length of internode and daughter branch were gross or long with soil and lagging straw and nonwoven fabric+straw. Cane growth was enhanced by burying in soil and lagging with+straw treatment. Crown gall occured higher in soil covered grape vines Labor saving was obtained in lagging with as much as 44% compared to burying in soil.

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A Study on the Standard Test Method for Thermal Resistance of Military Textile Thermal Insulator for Winter Season (방한을 목적으로 하는 군용 섬유제품 충전재의 보온성 시험방법에 대한 표준화 연구)

  • Yeo, Yong-heon;Hong, Seong-don;Lee, Min-hee;Kim, Kyung-pil;Chung, Il-han
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.9
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    • pp.492-500
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    • 2018
  • The performance evaluation of cold weather clothing is mainly carried out with thermal resistance. However, the results of the revised test method regarding the same specimen were decreased compare to previous one. In addition, there were deviations of the results among the authorized testing institutes according to the different interpretation of the KS test method. This makes it a considerable difficulty to the quality assurance of combat supplies. The purpose of this study is to minimize the variation of the results before and after the revision by analyzing the cause of the decrease in the heat insulation rate according to the revised test method. For this purpose, the difference between the test conditions before and after the revision of KS is analyzed and the possible results are reviewed. In addition, we want to minimize the result deviation between testing laboratories by analyzing the cause of the result deviation between test laboratories according to arbitrary interpretation of the standard. Based on this, we propose a standardized test method to prevent the decrease of the heat insulation rate by checking the pre-revision test method and the condition with the least deviation.

Studies on the Improvement of Nursery for Better Ripening Percentage and Prevention of Leaf Discoloration of Rice Variety 'Tongil' (통일벼의 등숙향상과 적고방지를 위한 묘대개선에 관한 연구)

  • Beom-Yeol Choi
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.15
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    • pp.99-113
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    • 1974
  • This experiment was carried out to find reasonable semi. hot seedbed system for early transplanting of "Tongil"rice cultivar. The quality of the young rice-plants, yield, and the occurrence of the reddish dry leaves were not significant differences between the seedbed with polyethylene tunnel and that of Rat covering. The per cent of healthy seedling of the soil preparation with the dry soil plowing was increased than that of the water soil plowing. The stability of the seedling cultivation of the thin layer straw mulching seedbed beneath the polyethylene film was higher than that of the common flat seedbed system.ed system.

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체크합시다 - 환절기 닭 호흡기 질병의 모든것

  • 권용국
    • Feed Journal
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    • v.3 no.9 s.25
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    • pp.136-141
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    • 2005
  • 환절기나 겨울철에 사람들은 독감, 천식, 비염 등 호흡기성 질환의 발병율이 높아지는 것과 동일하게 닭에서도 호흡기성 질병이 발생된다. 더군다나 닭은 어느 동물보다 호흡기를 구성하고 있는 실질장기들의 표면적이 넓어 그 만큼 많은 병원체에 쉽게 감염되며, 이에 따라 양계농장에서는 이들 전염병으로 피해가 속출하고 있다. 밤낮 기온차가 큰 환절기나 추운 겨울철에는 계사내 보온과 에너지절약, 이 두 가지 효과를 동시에 얻기 위해 노력하다 보면 신선한 산소의 제공

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업체탐방 - 바이오맥 - 계사 단열은 인슐래드로 해결! -

  • Jang, Seong-Yeong
    • KOREAN POULTRY JOURNAL
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    • v.41 no.5
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    • pp.110-113
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    • 2009
  • 단열목적으로 개발한 최첨단 진공세라믹 소재 인슐래드를 축사에 접목해 탁월한 효과를 자랑하는 기업이 있다. 지난해 벤처기업으로 등록된 바이오맥은 보온 보냉 효과가 뚜렷한 꿈의 소재 '인슐래드' 제품 판매와 '바이오 커튼'을 개발해 업계에서 주목받고 있다. 또한 부화율과 산란율 개선에 효과를 나타내는 항생제대체용 사료첨가제 '애니웰' 제품 개발과 금년부터 의욕적으로 시행하는 HACCP 컨설팅 등 기자재, 사료첨가제, 사양관리 등 축산농가의 모든 부분에 대해 연구하는 기업, 바이오맥을 찾았다.

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