• The Korean Journal of Ecology
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• v.15 no.2
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• pp.127-135
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• 1992

The effects of nacl concentration, temperatura, light and growth regulator(GA3, kinetin) on the tuber germination of s. maritimus were investigated. The germination percentage increased with decreasing nacl, showing salt tolerance through time, and with increasing temperature untile 20~30oC light / dark (12/12 hr) of optimal temperature. The multiplication of nacl and temperature on germination percentage and velocity, increased significantly in higher temperature than lower temperature in saline. The germination percentage showed high value in dark condition than in light condition which is the charracteristics of underground organ. and ga3 act as germination stimulator to overcome the inhibitory effect of nacl. The effect of ga3 showed significant differances on tubers of s. maritimus of germination but that of kinetin had a litter sffects on germination. Factors of nacl and temperature interacted significantly and the effects of nacl on germination percentage and velocity depended on temperature condition.

• Korea-Australia Rheology Journal
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• v.20 no.4
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• pp.213-220
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• 2008

The effects of temperature on the rheological properties of the solutions of poly(vinylidene fluoride-co-hexafluopropylene) (PVDF-HFP) in dimethyl acetamide (DMAc) were investigated in terms of frequency and concentration. The effects of temperature on the intrinsic viscosity of the solutions were discussed. In dynamic rheological measurement, the concentrated solutions showed a little unexpected rheological response; as temperature was increased dynamic viscosity was increased and the solutions exhibited more noticeable Bingham body character over the temperature range, 30 to $70^{\circ}C$. In addition, the solution gave longer relaxation time, lower value of loss tangent and higher value of yield stress at higher temperature and at higher concentration. On the other hand, the dilute solutions revealed that intrinsic viscosity was decreased and its Huggins constant was increased with increasing temperature. These physical parameters suggested that the increase of viscosity with increasing temperature resulted from the localized gelation of PVDF-HFP due to reduced solubility to the solvent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.771-776
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• 1993

Aqueous extraction of sea tangle at the temperature range of 60~10$0^{\circ}C$ was studied for temperature effects on soluble solids and protein yields, amino nitrogen, turbidity and viscosity of extracts. The solids and protein yield were increased as the temperature increased and most of solids and protein were extracted during 1 hour. The supernatant ratio after centrifugation showed significantly low for the extraction at 6$0^{\circ}C$. More temperature effects were found on turbidity and viscosity than yields. A significantly higher total amino nitrogen contents was obtained from higher temperature at initial stage of extraction and then the differences of them became to be narrow as the extraction prolonged further. The low values of 24.1% solids and 13.5% protein yields after 2 hours of extraction at 10$0^{\circ}C$ indicated that most of solids in sea tangle are insouble.

• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.1970-1974
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• 2011

The effects of convection on the measurement of the diffusion coefficients of liquids by the pulsed gradient spin echo (PGSE) NMR method at low temperature are discussed. To examine the generation of convective flows, we used four different types of sample tubes in the diffusion measurements with temperature variation; a normal 5 mm NMR tube, a Shigemi tube, an ELISE type tube, and a capillary tube. Below room temperature, the calculated diffusion coefficients of chloroform in 5 mm o.d. type tubes increased with decreasing temperature, while those in the capillary tube decreased linearly. The convective flow was found to be significant even at low temperature and it seemed to be mainly induced by the transverse temperature gradient. It was also found that the capillary tube was most appropriate to measure the diffusion coefficients, since its small diameter is effective in suppressing the convective flows at both high and low temperatures.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.3
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• pp.172-176
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• 2003

In this paper, we studied the effects of mold temperature on the microstructure of injection molded parts. The weld line decreases in length and width as mold temperature increases. We investigated the dimensional stability of the parts made of two kinds of resin(polypropylene and polystyrene) by varying the mold temperature. As the mold temperature is high, both the shrinkage ratio and the thickness difference for the PS parts decreases. But the observation of PP parts shows a tendency to increase. The easiness of cavity filling and transcription of the mold texture is improved as the mold temperature is high.

• Smart Structures and Systems
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• v.15 no.4
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• pp.1159-1175
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• 2015

In this study, the effect of temperature variation on the wireless impedance monitoring is analyzed for the tendon-anchorage connection of the prestressed concrete girder. Firstly, three impedance features, which are peak frequency, root mean square deviation (RMSD) index, and correlation coefficient (CC) index, are selected to estimate the effects of temperature variation and prestress-loss on impedance signatures. Secondly, wireless impedance tests are performed on the tendon-anchorage connection for which a series of temperature variation and prestress-loss events are simulated. Thirdly, the effect of temperature variation on impedance signatures measured from the tendon-anchorage connection is estimated by the three impedance features. Finally, the effect of prestress-loss on impedance signatures is also estimated by the three impedance features. The relative effects of temperature variation and prestress-loss are comparatively examined.

• Tribology and Lubricants
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• v.12 no.3
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• pp.55-62
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• 1996

Present study was undertaken to investigate the effects of composition ratio and temperature on the friction and wear of PTFE-polyimide composites under the atmosphere of nitrogen gas. The load range was 0.62-3.46 MPa, and the temperature range was room temperature and 200$^{\circ}$C. To mention some of the notable results, friction coefficient of PTFE 100% varied relatively little within the given load and temperature ranges. Polyimide 100% showed the lowest friction coefficient of 0.06 at 200$^{\circ}$C among all the experiments. PTFE 80%-polyimide 20% showed the lowest wear factors on the whole. Friction coefficient of PTFE 20%-polyimide 80% varied from the highest 0.35 to the lowest 0.09 among all the materials at room temperature, and showed almost the same lowest values with polyimide 100% at 200$^{\circ}$C. Suggestion of friction and wear mechanisms of the materials was tried to explain the observed phenomena including above mentioned results.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.05a
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• pp.30-33
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• 1994

This paper studies on the effect of DSC(Differential Scanning Calorimeter) analysis condition on the glass transition temperature of silica filled epoxy network polymer used for ultra-high voltage apparatus. The effects of temperature scanning rate specimen size and gas flow rate on measured glass transition temperature have been studied in order to select optimum thermal analysis condition.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1082-1086
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• 2004

Since the sheet forming of Mg alloy has many difficulties due to the low formability, many forming conditions need to be selected properly. Especially, the process variables should be investigated to increase the formability, such as, forming temperature. In this paper, the effects of forming process variables has been investigated using the bending and deep drawing process. A simple U-bending designed for mobile part could be formed in room temperature and springback amounts are surveyed. On the other hand, square cup part couldn't be formed in room temperature due to the low formability. Therefore, the effects of forming temperature are investigated in deep drawing process for square cup part. As a experimental and FEM results, the optimum forming temperature is presence and formability in a higher temperature is less than that of lower temperature. Above experimental results are compared with the FEM analysis and well coincided with the experimental results. Therefore, more detail investigations could be progressed to select more appropriate process conditions by the FEA.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.30 no.2
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• pp.83-91
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• 2018

A datacenter is a high energy consuming facility whose cooling energy consumption rate is 10~20 times larger than general office buildings. The higher the temperature of supply air from a CRAC (computer room air-conditioner) is supplied, the more energy efficient cooling is possible because of improving the COP of a chiller and advanced range of outdoor air temperature available for the economizer cycles. However, because the temperature of cold air flowing into server computers varies depending on air mixing configurations in a computer room, the proper supply air temperature must be considered based on the investigation of air mixing and heat dissipation. By these, this study aims to understand the effects of variation of the supply air temperature on the air flow distributions, temperature distributions and rack cooling efficiencies. Computational fluid dynamics (CFD) aided in conducting the investigation. As a result, the variation of the supply air temperature does not affect the air flow distributions. However, it mainly affects the temperature distribution. From the results of CFD simulations, Rack cooling indices (RCIHI and RCILO) were evaluated and showed the ideal state set at $19^{\circ}C$ of the supply air temperature.