• Title/Summary/Keyword: Temperature condition

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Thermal Analysis of Transportation and Storage Cask of Spent Nuclear Fuel for Forced Gas Drying Condition

  • Lim, Suk-Nam;Chae, Gyung-Sun;Han, Jae-Hyun;Park, Jae-Seok;Lee, Dong-Gyu
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2017.05a
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    • pp.153-154
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    • 2017
  • The thermal analysis of transportation and storage cask for SNF was conducted during short term loading operations for forced gas drying condition. The fuel cladding temperature in 6 regions of SNF in the cask during the short term loading operations for forced gas drying condition is shown in the Fig. 3. The thermal analysis results of calculated maximum cladding temperature in each process demonstrate that operating scenario of TFD in detailed design maintain well below the temperature limits of $400^{\circ}C$.

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Simulation of Solar/Absorption Cooling Hybrid System and Examination of Its Operating Condition (태양열을 이용한 흡수식 냉방시스템의 시뮬레이션과 운전조건의 검토)

  • Her, Jae-Young;Lee, Sang-Yong
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.14 no.1
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    • pp.1-11
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    • 1985
  • Solar/absorption cooling system was analyzed and its operating condition was examined. For the system, the optimum size of absorption refrigerator and collector area should be determined. As the temperature of water supplied to the generator increases, the collector efficiency decreases whereas the coefficient of performance of absorption refrigerator increases up to a certain point, and vice versa for decreasing of the temperature of water supplied to the generator . Thus if the reeling load is given, the appropriate operating condition can be determined between the two opposing trends by simulation program. As an example of the simulation, the case of Jejudo province was studied. Under the conditions (such as weather data and prices of components, etc.) given en the sample calculation, the result shows that the optimum temperature of water supplied to the generator turned out to be $80.3^{\circ}C$, and still shows a large economical disadvantage in present stage compared to the case of conventional vapor compression cooling/heating combined heat pump system.

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Emergence Characteristics of Weedy Rice under Flooding depth (담수 처리에 따른 잡초성벼의 출현 변화)

  • Hwang, Woon-Ha;Jeong, Jae-Hyeok;Lee, Hyeon-Seok;Park, Tae-Sun;Yang, Seo-Young;Choi, In-Bae;Choi, Kyung-Jin
    • Weed & Turfgrass Science
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    • v.7 no.3
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    • pp.171-179
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    • 2018
  • We investigated changes of weedy rice emergence and seed condition under different flooding depth condition using 100 accessions of weedy rice germplasm collected in South Korea. In 1 cm of soil buried depth condition, 54 and 57% of emergence was reduced under 5 and 10 cm of flooding depth conditions respectively compared to non-flooding condition. In 5 cm of soil buried depth condition, 66 and 84% of emergence was reduced under 5 and 10 cm of flooding depth conditions respectively compared to non-flooding condition. The 94% of weedy rice germplasm showed less than 10% of emergence rate at 10 cm of flooding depth condition. In flooding condition, seed number, which germinated but did not emerged, was increased. As a result of analyzing the correlation between effective accumulated temperature and seed condition, dead seed rate increased and germination rate decreased depending on effective accumulated temperature. However, emergence rate did not show significant correlation with growth temperature condition under flooding condition such as 5 or 10 cm of water depth, it decreased according to flooding period. In order to reduce the emergence rate of weedy rice, longer than 21 days of flooding might be needed.

Differences on Growth, Photosynthesis and Pigment Contents of Open-pollinated Pinus densiflora Families Under Elevated Temperature and Drought (온도 증가와 건조 스트레스에 따른 소나무 풍매차대묘의 가계간 생장, 광합성 및 광색소 함량 차이)

  • Kim, Gil Nam;Han, Sim-Hee;Park, Gwan Soo
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.16 no.4
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    • pp.285-296
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    • 2014
  • The impacts of high temperature and drought were studied on the seedlings of three families (superiorgangwon74, intermediate-gangwon77 and inferior-gangwon132) of P. densiflora which had been selected by the based on the growth indexes of 32-year-old. The seedlings were grown in controlled-environment growth chambers with combinations of four temperatures ($-3^{\circ}C$, $0^{\circ}C$, $+3^{\circ}C$ $+6^{\circ}C$; based on the monthly average for 30 years in Korea) and two water conditions (control, drought). The growth performance, photosynthetic parameters and photosynthetic pigment contents were measured at every 30 days under four temperatures and drought condition, and the end of each treatment. The superior family showed higher relative diameter at root collar growth rate and the dry weight than intermediate and inferior family in all treatments. Under elevated temperature and drought condition, growth rate was decreased, and seedlings showed lower growth rate than that of control in three families under low temperature. Photosynthetic rate, stomatal conductance and transpiration rate of three families decreased with the increase of temperature and drought condition, and that of seedlings under low temperature was lower than control. But under elevated temperature and drought condition, water use efficiency increased in three families. Photosynthetic pigment contents of leaves decreased under the increase of temperature and drought condition, but chlorophyll a/b ratio increased with the increase of temperature and drought condition in three families. The superior family showed higher total chlorophyll content than intermediate and inferior family in all treatments. In conclusion, P. densiflora is under changed temperature and drought condition, growth was decreased, seedlings more affected in elevated temperature than that of decreased temperature. The increase in monthly average temperature in Korea of more than $6^{\circ}C$, P. densiflora seedling growth in depending on region may decrease. In this study, the superior family(gangwon74) showed more excellent growth and physiological responses than intermediate (gangwon77) and inferior(gangwon132) family under changes temperature and drought.

Heat stress resistance of Ilmi

  • Hwang, Woon-Ha;Back, Jung Seon;An, Sung Hyun;Jeong, Jae-Heok;Jeong, Han-Yong;Lee, Hyeon-Seok;Yoon, Jong Tak;Lee, Gun-Hwi;Choi, Kyung-Jin
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.228-228
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    • 2017
  • Rice production and quality could be changed by temperature condition. Extremely high temperature event have been occurred more frequently for global warming. To increase rice quality against to global warming, breeding of heat tolerance rice cultivar is needed. Ilmi which is the one of Korean leading rice cultivar shows heat stress resistant character during ripening stage. Yield and quality (brown and milled rice) of Ilmi did not show significant different under high temperature condition compared to control condition. However, the main physiological characters for heat resistance of Ilmi have been not investigated yet. Therefore we try to investigate the heat tolerance characters of Ilmi. Two rice cultivars, Ilmi and Ilpum-which is heat susceptible rice cultivar, were cultivated under natural condition in wagnor pot until heading was appeared. After checking heading date, each material was cultivated under different temperature condition, heat($32/22^{\circ}C$) and control($26/16^{\circ}C$) condition. Anti-oxidant enzyme activity was checked during ripening stage in each material. Catalase and ascorbic peroxidase activity of leaf under heat stress condition were higher in Ilmi than Ilpum especially early ripening stage. Analyzing of stress resistance using $H_2O_2$, the flag leaf of Ilmi showed more green color than Ilpum with higher chlorophyll content than those of Ilpum. We also checked the amount of $H_2O_2$ content in young leaf of each material by treating high temperature. $H_2O_2$ content in each material was increased according to treatment time. However $H_2O_2$ content of young leaf in Ilmi was less than those in Ilpum. Also catalase and ascorbic peroxidase activity in leaf increased much faster in Ilmi than Ilpum. With those data, we confirmed that heat stress resistance of Ilmi is due to the higher anti-oxidant activity against to stress condition. We will investigate the heat tolerance characters of Ilmi more in further study to enhance the breeding effect of heat stress tolerance rice.

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Influence of Temperature on the Treatment Efficiency of Chlorinated Organic Substances in Groundwater by Permeable Reactive Barrier (염소계 유기화합물로 오염된 지하수의 반응성 투과 벽체 처리 효율에 대한 온도의 영향)

  • Kim, Sun-Hye;Kim, Eun-Zi;Kim, Dong-Su
    • Journal of Korean Society on Water Environment
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    • v.30 no.2
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    • pp.175-183
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    • 2014
  • The influence of temperature on the treatment efficiency of chlorinated organic substances contained in groundwater by permeable reactive barrier which is composed of $Fe^{\circ}$ has been investigated by constructing the Pourbaix diagrams for Fe-$H_2O$ system at different temperatures based on thermodynamic estimation. In aerobic condition, the equilibrium potentials for $Fe^{\circ}/Fe^{2+}$ and $Fe^{2+}/Fe^{3+}$ were observed to increase, therefore, the dechlorination reaction for organic pollutants by $Fe^{\circ}$ was considered to decline with temperature due to the diminished oxidation of reactive barrier. The result for the variations of the ionization fraction of $Fe^{2+}$ and $Fe^{3+}$ ion in the pH range of 0 ~ 2.5 obtained by employing Visual MINTEQ program showed that the ionization fraction of $Fe^{2+}$ increased with pH, however, that of $Fe^{3+}$ decreased symmetrically and the extent of the variation of ionization fraction for both ions was raised as temperature rises. The equilibrium pH for $Fe^{3+}/Fe(OH)_3$ was examined to decrease with temperature so that the treatment efficiency of chlorinated organic substance was expected to decrease with temperature due to the enhanced formation of passivating film in aerobic condition. The change of the reactivity of a specific chemical species with temperature was defined quantitatively based on the area of its stable region in Pourbaix diagram and depending on this the reactivity of $Fe^{3+}$ was shown to decrease with temperature, however, that of $Fe(OH)_3$ was decreased monotonously as temperature is raised for $Fe^{3+}/Fe(OH)_3$ equilibrium system. In anaerobic condition, the equilibrium potential for $Fe^{\circ}/Fe^{2+}$ was observed to rise and the equilibrium pH for $Fe^{2+}/Fe(OH)_2$ were examined to decrease as temperature increases, therefore, similar to that for aerobic condition the efficiency of the dechlorination reaction for organic substances was considered to be diminished when temperature rises because of the reduced oxidation of $Fe^{\circ}$ and increased formation of $Fe(OH)_2$ passivating film.

The Effect of Molding Conditions on the Surface Gloss of HIPS Molding (HIPS 성형품에서 성형조건이 표면 광택에 미치는 영향)

  • Jeong, Y.D.;Lee, M.H.
    • Journal of Power System Engineering
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    • v.4 no.3
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    • pp.81-85
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    • 2000
  • The surface gloss of the injection molded part is one of the most significant point for evaluation the quality of products appearance. The effects of molding condition on the gloss of HIPS(High Impact Poly Styrene) molded part were investigated in this work. The measurements of gloss on the surface of molded part were carried out with different melt temperature, mold temperature, injection pressure and holding pressure. We observed the result of HIPS gloss compared with our's previous ABS study. The more melt and mold temperature increased, the brighter the gloss increase. Holding and injection pressure had little effect on the gloss. The gloss was effected in order of melt temperature, mold temperature, injection pressure, holding pressure.

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On-line Monitoring and Diagnostics for Distribution Panel System (배전반 시스템의 온라인 감시 및 진단)

  • Choi, Yong-Sung;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.04c
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    • pp.106-110
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    • 2008
  • Continuous on-line temperature monitoring allows corrective measures to be taken to prevent upcoming failure. Continuous temperature monitoring and event recording provides information on the energized equipment's response to normal and emergency conditions. On-line temperature monitoring helps to coordinate equipment specifications and ratings, determine the real limits of the monitored equipment and optimize facility operations. Using wireless technique eliminates any need for special cables and wires with lower installation costs if compared to other types of online condition monitoring equipment. In addition, wireless temperature monitoring works well under difficult conditions in strategically important locations. Wireless technology for on-line condition monitoring of energized equipment is applicable both as standalone system and with an interface with power quality monitoring system.

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A study for improvement of engine bearing reliability based on temperature analysis (엔진 CON-ROD베어링 내 SCUFFING성 향상에 관한 연구)

  • 최재권;이정현
    • Journal of the korean Society of Automotive Engineers
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    • v.14 no.2
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    • pp.110-119
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    • 1992
  • Crank pin temperatures were measured and analyzed to find out practical method which can predict the engine bearing reliability. The measuring points were determined to be near the MOFT region and far from that by theoretical calculation. The effect of engine running condition, oil temperature, the change of oil circuit into bearing and crankshaft endplay on crank pin temperature were experimentally tested. The result obtained was as following. The crank pin temperature was dependent on oil film thickness and directly influenced by the change of test condition. Also, the length of the crankshaft endplay was confirmed to be critical to connecting rod bearing failure. In conclusion, we found that the measurement method of crank pin temperature can be used for predicting the engine bearing reliability.

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High-Temperature Structural Analysis on the Small-Scale PHE Prototype under the Test Condition of Small-Scale Gas Loop (소형가스루프 시험조건에서 소형 공정열교환기 시제품의 고온구조해석)

  • Song, Kee-nam;Hong, S-D;Park, H-Y
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.8 no.1
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    • pp.1-7
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    • 2012
  • A PHE (Process Heat Exchanger) is a key component required to transfer heat energy of $950^{\circ}C$ generated in a VHTR (Very High Temperature Reactor) to the chemical reaction that yields a large quantity of hydrogen. A small-scale PHE prototype made of Hastelloy-X is being tested in a small-scale gas loop at Korea Atomic Energy Research Institute. In order to properly evaluate the high-temperature structural integrity of the small-scale PHE prototype, it is very important to impose a proper constraint condition on its structural analysis model. For this effort, we tried to impose several constraint conditions on the structural analysis model and consequently fixed a proper and effective displacement constraints.