• Title/Summary/Keyword: Room temperature dry

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Analysis of Temperature and Humidity Distribution in a Dry Room (Dry Room내의 온.습도 분포 해석)

  • 이관수;임광옥;안강호;정영식
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.13 no.6
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    • pp.524-531
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    • 2001
  • The temperature and humidity distribution in a dry room are studied numerically by using standard$\kappa-\varepsilon$ turbulence model. In order to evaluate effective heat and moisture ventilation characteristics inside the room, the heat removal capacity and moisture exhaust efficiency are introduced. An effective ventilation control is analyzed by evaluating quantitatively temperature and humidity distributions. It was found that the mean absolute humidity inside the room was almost constant with approximately 0.1905g/kg air regardless of the models and the heat generation rates. This was believed that the moisture generation by workers was relatively small. 40% improvement of the critical decay time was achieved, through the modifications of design variables.

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Changes of Rice Storage Proteins Affected by Dry and Storage Temperature (건조 및 저장조건에 따른 쌀 저장단백질의 변화양상)

  • Shin, Pyung-Gyun;Chang, An-Cheol;Hong, Seong-Chang;Lee, Ki-Sang;Lee, Keum-Hee;Lee, Yong-Bok
    • Korean Journal of Environmental Agriculture
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    • v.27 no.4
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    • pp.456-459
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    • 2008
  • Quality of rice grain changes during dry storage with internal physiological changes and external injury by organism. Storage rice changes by condition with respiration via variable temperature, hydrolysis enzyme reaction, lipid peroxidation occurs with change of palatability. During dry storage, physiological change with protein variation pattern was examined by image analysis on proteomic technology. Analysis revealed that protein activity had no change store at room temperature and store at $40^{\circ}C$, but decreased store at $60^{\circ}C$. Analysis of variable hydrophobic protein pattern revealed that protein activity of beta-tubulin, protein disulfide isomerase, vacuolar ATPase b subunit, globulin was not significantly decreased all dry and store condition. However, heat shock protein 70, and glutathione transferase was significantly decreased when rice dried at $60^{\circ}C$ compared with room temperature and $40^{\circ}C$ dry condition.

Effectiveness of Ventilation Control in a Dry Room with a Heat and Moisture Source

  • Lee, Kwan-Soo;Lim, Kwang-Ok;Ahn, Kang-Ho;Jung, Young-Sick
    • International Journal of Air-Conditioning and Refrigeration
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    • v.9 no.4
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    • pp.1-9
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    • 2001
  • The temperature and moisture distributions in a dry room with a heat and moisture source -i.e., workers- are studied numerically by using a standard $k-\varepsilon$ turbulence model. In order to evaluate the effectiveness of heat and moisture ventilation inside the room, the heat removal capacity and the moisture exhaust efficiency are introduced. The effectiveness of ventilation control is analyzed by evaluating the temperature and humidity distributions in the room quantitatively. It is found that the mean absolute humidity inside the room is almost constant regardless of the models and the heat generation rates in this study range. This results from the fact that the moisture generation by the workers was relatively small. Through the modification of the design, 40% improvement in critical decay time was achieved.

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Ionic liquids to the rescue? Overcoming the ionic conductivity limitations of polymer electrolytes

  • Hendcrson W.A.;Shin J.H.;Alessandrini F.;Passcrini S.
    • 한국전기화학회:학술대회논문집
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    • 2003.11a
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    • pp.153-168
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    • 2003
  • Polymer electrolytes - solid polymeric membranes with dissolved salts - are being intensively studied for use in all-solid-state lithium-metal-polymer consumer electronic device. The low ionic conductivity at room temperature of existing polymer electrolytes, however, has seriously hindered the development of such batteries for many applications. The incorporation of salts molten at room temperature (room temperature ionic liquids or RTILs) into polymer electrolytes may be the necessary solution to overcoming the inherent ionic conductivity limitations of 'dry' polymer electrolytes.

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The effect of peak cladding temperature occurring during interim-dry storage on transport-induced cladding embrittlement

  • Kim, Kyu-Tae
    • Nuclear Engineering and Technology
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    • v.52 no.7
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    • pp.1486-1494
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    • 2020
  • To evaluate transport-induced cladding embrittlement after interim-dry storage, ring compression tests were carried out at room temperature(RT) and 135 ℃. The ring compression test specimens were prepared by simulating the interim-dry storage conditions that include four peak cladding temperatures of 250, 300, 350 and 400 ℃, two tensile hoop stresses of 80 and 100 MPa, two hydrogen contents of 250 and 500 wt.ppm-H and a cooling rate of 0.3 ℃/min. Radial hydride fractions of the ring specimens vary depending on those interim-dry storage conditions. The RT compression tests generated lower offset strains than the 135 ℃ ones. In addition, the RT and 135 ℃ compression tests indicate that a higher peak cladding temperature, a higher tensile hoop stress and the lower hydrogen content generated a lower offset strain. Based on the embrittlement criterion of 2.0% offset strain, an allowable peak temperature during the interim-dry storage may be proposed to be less than 350 ℃ under the tensile hoop stress of 80 MPa at the terminal cool-down temperature of 135 ℃.

황색종 잎담배 공동건조장의 환경개선

  • 신승구;백기현;이승철
    • Journal of the Korean Society of Tobacco Science
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    • v.20 no.2
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    • pp.160-165
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    • 1998
  • The Joint curing barns for flue-cured tobacco is a favorite with the tobacco farmers in Korea. However, most of farmer utilizing the joint curing barns indicated many problems such as high temperature and noise in the working room and a dry of cured leaves in the storage room. A structure of Joint curing barns has been modified to meet the needs of tobacco farmers. Compared with the unimproved joint curing barns, the improved one showed that the noise of workshop decreased about 7.7~10.8db, the amount of $CO_2$ decreased 40~50ppm in a working room and 80~100ppm in a machine room. Ammonia gas decreased 0.29mg/㎥ and the temperature of a working room dropped about 2.1~3.5$^{\circ}C$. The amount of air flow in a working room increased 23.2% at a site being 2m away from the entrance and 30.8% at a center. The inner temperature of the improved storage room showed that maximum temperature dropped about 3$^{\circ}C$, minimum temperature was high about 2$^{\circ}C$. The highest relative humidity was low 6%, the lowest one increased high about 10% when compared with the unimproved joint curing barns.

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High Temperature Tribological Behaviour of Particulate Composites in the System SiC-TiC-TiB2 during Dry Oscillating Sliding

  • Wasche, Rolf;Klaffke, Dieter
    • The Korean Journal of Ceramics
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    • v.5 no.2
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    • pp.155-161
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    • 1999
  • The tribological behaviour of monolithic SiC as well as SiC-TiC and SiC-TiC-$TiB_2$ particulate composite materials has been investigated in unlubricated oscillating sliding tests against $Al_2O_3$ at temperature in the range from room temperature up to $600^{\circ}C$. At temperatures below $600^{\circ}C$ the wear rate of the systems with the composite materials was up to 20 times lower than the wear of the $Al_2O_3$/SiC system and was dominated by the oxidation of the titanium phases. At $600^{\circ}C$ the oxidation rate of the TiC and -TEX>$TiB_2$ grains becomes predominant resulting in an enhanced wear rate of the composite rate of the TiC and TiB2 grains becomes predominant resulting in an enhanced wear rate of the composite materials. The coefficient of friction shows similar values for all materials of investigation, increasing from 0.25…0.3 at room temperature to 0.7…0.8 $600^{\circ}C$. The wear of the $Al_2O_3$/SiC system is mainly abrasive at temperatures above room temperature and is characterised by an enhanced wear of the alumina ball at $600^{\circ}C$.

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Effects of cold and room temperature storage on the sprouting and marketability of early-grown spring potatoes

  • Heon-Seop Won;Kyusuk Han;Young Hun Lee
    • Food Science and Preservation
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    • v.31 no.1
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    • pp.33-45
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    • 2024
  • Three spring potato varieties (Atlantic, Chubaek, and Superior) were cultivated for 80, 90, and 100 days and compared in terms of their total and marketable yields and specific gravities. Subsequently, changes in the quality parameters (weight loss, sprouting rate, disease incidence, dry weight, and specific gravity) of potatoes cultivated for 100 days were monitored during two-month storage in improved and semi-underground warehouses at 4℃ and room temterature. The productivities of Atlantic, Superior, and Chubaek were maximized at cultivation periods of 100, 100, and >90 days, respectively. In all cases, cold storage resulted in <5.3% weight loss and no marketability loss. However, two-month room temperature storage resulted in pronounced marketability loss due to weight loss (6.2, 7.3% and 10.9% for Atlantic, Superior, and Chubaek, respectively) and sprouting (in ~13%, >75%, and 99% of Atlantic, Superior, and Chubaek tubers, respectively). The marketability of Atlantic, Superior, and Chubaek during cold storage was maintained for >2, ~2, and <2 months, respectively. All varieties were characterized by rapid sprouting, low dry weight and specific gravity, and rapid marketability loss during storage.

A Study on the Reaching Time of Setting Temperature with Ventilation Air (급기환기량에 따른 공조기의 설정온도 도달특성 분석 연구)

  • Kang Tae-Wook
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.1
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    • pp.50-57
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    • 2006
  • This study describes to analyze the cooling load characteristics for a room air conditioner as a function of supply ventilation air when an air conditioner is running An experimental apparatus consists of a test room, a room air conditioner, a humidifier, an electrical heater a supply fan and a controller The reaching time to the inside setting temperature of the room air conditioner with is evaluated theoretically and experimentally in a conditioned space cooling loads such as supply ventilation air, lighting, occupancy and infiltration. In the conditions of cooling loads for the supply ventilation air of 9.5 L/s(0.98 ACH). lights. one Person, and infiltration, the reaching time to the inside setting temperature ($27\;^{\circ}C$ dry-bulb) increases up to $35\%$ more than for no supply ventilation air condition. Theoretical modelling of the reaching time shows good agreement with experimental results.

Development of drying apparatus using 2-way condensation for marine products (2방식 응축을 이용한 수산물 건조 장치 개발)

  • Hwang, Jea-Ho
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.42 no.4
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    • pp.259-266
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    • 2006
  • In this study, the 2-way condensation system was designed applying air-to-air heat pump to dry a marine product such as squid in the winter. And to be made the drying apparatuses by this system, there are two kinds of type, A type, was set a compressor outside of the drying apparatus, B type, was set a compressor in the drying room. And then the variations of temperature in drying room were measured to compare the heating performance of the drying apparatuses between A type and B type at $-6.5^{\circ}C$, outdoor temperature. The temperature of the drying room for B type was increased to $36^{\circ}C$ but the temperature of the drying room for A type was not increased to $36^{\circ}C$, to be increased to $20^{\circ}C$.