• Title/Summary/Keyword: Higher Temperature

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Performance of a room air conditioner using R410A according to the variation of outdoor temperature (실외온도 변화에 따른 R410A 적용 에어콘 시스템의 성능)

  • 김병순;이승홍
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.4
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    • pp.537-541
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    • 1999
  • The system performance of a room air conditioner using R410A was experimentally evaluated and compared with that of R22 system. The results indicated that the cooling EER(energy efficiency ratio) of R410A was 1% higher than that of R22 at the outdoor temperature of $35^{\circ}C$. As outdoor temperature increases above $35^{\circ}C$ ambient, EER of the R410A system decreased more substantially compared with R22 system. R410A showed higher compressor discharge temperature than that of R22 system at the outdoor temperature of higher than $50^{\circ}C$.

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Effect of the Nano Ceria Slurry Characteristics on end Point Detection Technology for STI CMP (STI CMP용 가공종점 검출기술에서 나노 세리아 슬러리 특성이 미치는 영향)

  • 김성준;강현구;김민석;백운규;박재근
    • Journal of the Semiconductor & Display Technology
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    • v.3 no.1
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    • pp.15-20
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    • 2004
  • Through shallow trench isolation (STI) chemical mechanical polishing (CMP) tests, we investigated the dependence of pad surface temperature on the abrasive and additive concentrations in ceria slurry under varying pressure using blanket film wafers. The pad surface temperature after CMP increased with the abrasive concentration and decreased with the additive concentration in slurries for the constant down pressure. A possible mechanism is that the additive adsorbed on the film surfaces during polishing decreases the friction coefficient, hence the pad surface temperature gets lower with increasing the additive concentration. This difference in temperature was more remarkable for the higher concentration of abrasives. In addition, in-situ measurement of spindle motor was carried out during oxide and nitride polishing. The averaged motor current for oxide film was higher than that for nitride film, meaning the higher friction coefficient.

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An Analysis of Examination of Eco-City Planning Scenario for Constructing Urban Integrated Energy System (차세대에너지시스템 구축을 위한 친환경 도시계획 시나리오 검토)

  • Yeo, In-Ae;Yee, Jurng-Jae;Yoon, Seong-Hwan
    • 한국태양에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.181-184
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    • 2009
  • This study aimed at framing alternative urban planning scenarios reflecting urban planning factors, performing urban climate simulation and evaluating eco-friend and low energy characteristics of each scenario on the viewpoint of urban temperature and energy savings on the target of the costal city including Haeundae District in Busan The results are as follows. 1)The fact that urban higher temperature is approximately 2.5 times higher in the building constructed area than whole urban area was represented severe higher temperature phenomenon in the built-up area. Ground greening, water scenario and soil scenario could be expected peek air temperature alleviating effect in order. Especially water scenario had significant effect(maximum $2.5^{\circ}C$) on lowering of air temperature.

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Preparation and Properties of Polymer PTC Composites for Process Safety (공정안전용 Polymer PTC 소재의 제조 및 특성)

  • 강영구;조명호
    • Journal of the Korean Society of Safety
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    • v.18 no.3
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    • pp.101-108
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    • 2003
  • Polymeric positive temperature coefficient(PTC) composites have been prepared by incorporating carbon black(CB) into high density polyethylene(HDPE), polyphenylene sulfide(PPS) and polybutylene terephthalate(PBT) matrices. A PTC effect was observed in the composite, caused by the large thermal expansion due to He consecutive melting of HDPE, PPS and PBT crystallites. This theory is based upon the premise that the PTC phenomenon is due to a critical separation distance between carbon particles in the polymer matrix at the higher temperature. The influence of PTC characteristics of the PPS/CB composite can be explained by DSC result. HDPE, one of prepared composition, exhibit the higher performance PTC behavior that decreaseing of negative temperature coefficient(NTC) effect and improved reproducibility by chemically crosslinking. Also, PBT/CB and PPS/CB composites exhibit the higher PTC peack temperature than HDPE/CB PTC composite, individually $200^{\circ}C$ and $230^{\circ}C$. These PTC composite put to good use in a number of safety application, such as self$.$controlled heater, over-current protectors, auto resettable switch, high temperature proctection sensor, etc.

The Effects of Temperature, Starvation, and Kind of Foods on Growth, RNA/DNA Ratios and Protein Contents during the Early Life Stages of Olive Flounder (Paralichthys olivaceus)

  • Gwak Woo-Seok;Tanaka Masaru
    • Fisheries and Aquatic Sciences
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    • v.7 no.4
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    • pp.192-203
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    • 2004
  • The effects of temperatures, starvation, and kind of foods on growth, RNA/DNA ratio and protein contents during metamorphosis and early juvenile stage of olive flounder (Paralichthys olivaceus) were examined. During metamorphosis, warm-acclimated fish showed higher RNA and DNA content than those of the cold-acclimated fish, excepting H stage (28 DAH) at which the ratio was higher at cold temperature. RNA/DNA ratio during metamorphosis showed similar values at two temperatures tested. However, after 42 DAH warm-acclimated juveniles had higher DNA content compared with cold-acclimated fish, resulted in marked decreases in RNA/DNA ratios. Higher RNA content at H stage of cold-acclimated fish was consistent with an increase in protein content. Growth of fish rearing at warm temperature was higher than those of fish at cold temperature during all experiments. In starvation experiment, contents of DNA, RNA and protein significantly decreased. Even though there were no significant differences in total length (TL) and body weight between the live mysid-fed and artificial pellet-fed fish at 35 mm TL, both RNA/DNA and protein/DNA ratios of the former group was significantly higher than those of the latter due primarily to lower DNA content of the live mysid-fed group. The results from this study suggest that temperature, starvation and kind of foods should be considered when RNA/DNA ratio applied to assessing the cultured larval and juvenile fish condition.

A Study for Automatic Temperature Control of the Heating-Cooling System with Heat Pump (히트펌프 냉·난방 시스템의 온도 자동제어에 관한 연구)

  • Koo, Chang-Dae
    • Journal of the Korean Society of Industry Convergence
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    • v.14 no.4
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    • pp.143-149
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    • 2011
  • The experiment has been investigated the room temperature change under adjusting 4-way valve which was installed for cooling and heating switch. Beside, the temperature of heat pump was controlled automatically for autonomously adjusting temperature and maintaining a constant room temperature. As results, Inlet & outlet temperature differences of compressor are $95^{\circ}C$ in cooling condition and $57^{\circ}C$ in heating condition. Therefore, Compression efficiency of cooling effect is higher than heating effect. In addition, Heat exchange effect of Cooling system condition is higher than heating system. This results can be used for studying about automatic temperature control of cooling and heating system with heat pump and 4way valve.

Effect of Ironing Temperature on the Removal of Poly Vinyl Alcohol Size (PVA 가호 직물의 다림질 온도가 탈호률에 미치는 영향)

  • 이정옥
    • Journal of the Korean Home Economics Association
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    • v.18 no.4
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    • pp.13-16
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    • 1980
  • In cotton fabric sizing the domestic material is normally starch finds itself more frequent uses than the PVA size does. In this study we have examined the effects of ironing temperature and washing temperature on the removal of sized PVA by washing and have got following temperature on the removal of sized PVA by washing and have got following results: 1. the removal of PVA is related approximately to the reciprodal of the ironing temperature. 2. the higher the ironing temperature, the lower is the removal of PVA; and if the ironing temperature is higher than $140^{\circ}C$ the removal of PVA decreases abruptly even if the washing temperature were still high. 3. The most appropriate washing temperature should be at least $75^{\circ}C$when the ironing is carried out at 10$0^{\circ}C$ the same holds for $80^{\circ}C$to $120^{\circ}C$and $90^{\circ}C$to $120^{\circ}C$, respectively.

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Effect of ethphon treatment on the maturation of Plum fruits(Prunus salisina) and changes of the quality as affected by storage conditions (에테폰 처리가 자두과실의 성숙과 수확후 유통방법이 품질에 미치는 영향)

  • 임병선;이종석
    • Food Science and Preservation
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    • v.3 no.2
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    • pp.155-170
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    • 1996
  • In order to determine the physiolosical characteristics of plum fruits(Oishi wase) during maturation and guilty according to temperature after harvest, (2-chloroethyl) phosphonic acid(ethphon) 390ppm was sprayed on plum tree 11days before commercial matuarity in Suwon area. And also this study was acted to investigate fruits quility(Formosa) influenced by temperature(room, low) and polyethylene films(0.03, 0.06, 0.1mm), 1. Effect of ethphon on the fruits maturation and fruits(Oishi wase) quility according to temperature ofter harvest. Ethephon stimulated fruits ripening but the firmness was reduced rapidly. Soluble solids and titratable acidity was not very different than each treatment. Carbon dioxide and ethylene production were advanced and the production peak were shown earlier by ethephon treatment as compared with control fruit. Anthocyanin development was enhansed rapidly by ethephon treatment but it exerted a bad influence on fruits color after harvest, The soluble sugars in fluits were mainly glucose, sucrose, and fructose. Those content were higher in treated fruit than control. The organic acid was mainly malic acid. The shelf life was less than about 5days at room temperature and about 10 days at low temperature. 2. Fruits(Formosa) quility as affected by polyethylene film bagging. The polyethylene films well maintained the firmness both room and low temperature. Low temperature was more effective in maintaining titratable acidity than room temperature, especially polyethylene films. On the Other hand, soluble solids content was not shown wide differance between room and low temperature. Polyethylene film showed a high resperation rate, the rate was higher at room temperature than low temperature and thicker films revealed higher rate. Otherwise, ethylene production was low in all treatment Polyethylene film inhibited the coloration of fruits, decreased anthocyanin content. Fruits coloration delayed by low temperature in control. The shelf life of plum fruits was about 6 days at room temperature and 13 days at low temperature in control Polyethylene film had no advantage on shelf life both at room and low temperature.

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A Study on Preference of Salinity and Temperature of Soups Served in the Institutional Foodservice Establishment (급식업체에서 제공하는 국류의 적정 염도와 온도에 관한 연구)

  • Cho, Mee-Hee;Kim, Sun-Joo;Lee, Kyung-Hee
    • Journal of the East Asian Society of Dietary Life
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    • v.18 no.4
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    • pp.601-607
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    • 2008
  • This study was examined the preferred temperature and salinity of soup in various demographic groups in order to establish the desirable serving renditions of soup for customers' satisfaction and health. Temperature and salinity were measured in August and November in order to determine the seasonal variation in preference using a digital salinity-temperature measuring device. Four demographic groups totaling 530 were from foodservice establishments in elementary schools(ES: male 68/female 59), middle-high schools(MHS: 62/69), universities(UNIV: 72/67) and companies(COM: 69/64) in Seoul. Various thin or thick soups which are typically served in foodservice establishments were served hot(below $90^{\circ}C$) and warm(below $40^{\circ}C$) in a 50mL portion: salty(1.2%) and less salty(0.4%) at $55{\pm}2^{\circ}C$. The preferred salinities and temperatures of the soups were found to be 0.74%, 0.82%, 0.64% and 0.67% and $49.65^{\circ}C$, $54.24^{\circ}C$, $57.56^{\circ}C$, $58.81^{\circ}C$ for the ES, MHS, UNIV and COM groups, respectively. The preferred temperatures of the soups were increased depending on the age, so the positive correlation was shown between temperature and age. However the preferred salinities of soups were not effected. There was no consistent tendency between men and women in temperature. For salinity, men preferred $0.04{\sim}0.12%$ higher than women in the ES, MHS and UNIV groups. There is no consistent tendency between thin and thick soup in temperature. All groups preferred higher salinity in the thick soup than in the thin soup. Most of the customers preferred a higher temperature and higher salinity in November than in August.

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Burning-Temperature Change of Living Branches and Leaves of Pinus rigida and Larix leptolepis (고온로의 가열 온도에 의한 리기다소나무와 일본잎갈나무 생엽과 생지의 연소온도변화)

  • Kim, Kwan-Soo;In-Soo Jang;Ki-Don Park;Su-Jung Kim
    • The Korean Journal of Ecology
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    • v.18 no.3
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    • pp.333-340
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    • 1995
  • This study aims to examine how the amount of sample and changes in combustible temperature of living branches and leaves treated with high temperature are associated with combustible time of two coniferous trees, Pinus rigida (R) and Larix leptolepis (L), which are the main victims of forest fire. During the first thirty minutes at $80^{\circ}C$, moisture content of R was higher than that of L by 12%, but after four hours, the moisture content was both lowered by 4~5% and turned to highly combustible leaves. With living leaves, the maximal combustible temperature, regardless of heating temperature, turned out to be higher than normal temperature by $67~140^{\circ}C$, and that with living branches, it was higher by $113~207^{\circ}C$. Also, with living leaves (R, L), the duration time of combustion was as follows: 605, 906 seconds at $400^{\circ}C$ and 76, 227 seconds at $600^{\circ}C$, respectively. Concerning the relation between the amount of burnt fuel and maximal temperature, the more the former was, the higher the latter. The total amounts of combustion heat of living branches and living leaves were 1, 121 Cal (20.8%) and 1, 137 Cal (21.4%), respectively. The total amount of combustion heat increased in proportion to the amount of consumed fuel: 100 g of living leaves and branches gave rise to 128 Cal, whereas 300 g did 556 Cal, that was more than three times.

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