• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.19-26
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• 2003

Experimental measurements of flame structure and soot characteristics were performed for ethene inverse diffusion flames (IDF). IDF has been considered as the excellent flow field to study the incipient soot because soot particle do not experience the oxidation process. In this study, LIF image clarified the reaction zone of IDF with OH signal and PAH distribution. laser light scattering technique also identified the being of soot particle. To address the degree of soot maturing, C/H ratio and morphology of soot sample were investigated. From these measurements, the effect of flow residence time and temperature on soot inception could be suggested, and more details on soot characteristic in the IDF was determined according to fuel dilution and flame condition. The fuel dilution results in a decrease of temperature and enhancement of residence time, but the critical dilution mole fraction is existed for temperature not to effect on soot growth. Also, the soot inception evolved on the specific temperature and its morphology are independent of the fuel dilution ratio of fuel.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.3 no.1
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• pp.44-48
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• 2002

It is necessary to keep Kimchi at 0~5$^{\circ}C$ all around the year to maintain its taste, which is very sensitive to temperature changes. In addition to temperature for maintenance of taste, property of container is also important to control the activity of bacteria involved in Kimchi. As a pottery container is the best one for the bacterial activity, it was used to store Kimchi. Pottery is shielded by cooling pipe directly, and temperature of Kimchi is controlled by the independent temperature controller.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1992.05a
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• pp.117-121
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• 1992

Zinc oxide thin films were obtained from zinc acetate-2-water and oxygen by photo-CVD method. (1) The formation of ZnO films sarts from 100[$^{\circ}C$] and the deposition rate increases with increasing substrate temperature. (2) The rate of deposition was also affected by flow rates of O$_2$(reaction gas) and N$_2$(Carrier gas). (3) The deposition rate decreases with increasing O$_2$mole rate. (4) The transmission of the films was independent of oxygen mole rate and it was largely affected substrate temperature. (5) The electric resistivity of th films was largely varied at oxygen mole rate 10[%] and above 20[%], a plateau was encountered. Also, it increases with increasing substrate temperature. As the results, at substrate temperature: 200[$^{\circ}C$]; O$_2$gas mole rate:10[%]; reation time:10[min] pressure: 10$\^$-2/[atm], deposition rate; transmittance; resistivity were 780[A$\^$0/; 94[%]; 7${\times}$10$\^$-2/[$\Omega$$.$cm] respectively.

• Nuclear Engineering and Technology
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• v.50 no.2
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• pp.306-312
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• 2018

There is an increasing need in the United States and around the world to move used nuclear fuel from wet storage in fuel pools to dry storage in casks stored at independent spent fuel storage installations or interim storage sites. Under normal conditions, the Nuclear Regulatory Commission limits cladding temperature to $400^{\circ}C$ for high-burnup (>45 GWd/mtU) fuel, with higher temperatures allowed for low-burnup fuel. An analysis was conducted with FRAPCON-4.0 on three modern fuel designs with three representative used nuclear fuel storage temperature profiles that peaked at $400^{\circ}C$. Results were representative of the majority of US light water reactor fuel. They conservatively showed that hoop stress remains below 90 MPa at the licensing temperature limit. Results also show that the limiting case for hoop stress may not be at the highest rod internal pressure in all cases but will be related to the axial temperature and oxidation profiles of the rods at the end of life and in storage.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.8
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• pp.1552-1557
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• 2007

In this work, temperature stable pulse width modulation controller using bandgap reference voltage is proposed. Two bandgap reference voltages are designed by using BiCMOS technology which are temperature dependent and independent voltage references. PWM controller is designed by using 3.3 volt supply voltage and the output frequency is 1MHz. From simulation results, the variation of output pulse width is less than form +0.86% to -0.38% in the temperature range $0^{\circ}C\;to\;70^{\circ}C$.

• Journal of the Optical Society of Korea
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• v.17 no.4
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• pp.300-304
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• 2013

Novel breakthrough random-hole optical fibers (RHOFs) are fabricated in a draw tower facility, by tapering an optical fiber preform packed with a silica powder mixture capable of producing air holes in situ at the high temperature of tens of hundreds in degrees Celsius. Structural and propagation characteristics of the porous RHOF are explained briefly. Experimental investigations of the invented RHOF are performed for pressure sensor applications. Remarkable results are obtained for the RHOF with desirable pressure sensitivity independent of temperature, as is required for harsh conditions as in oil reservoirs.

• Journal of Oriental Medical Thermology
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• v.2 no.1
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• pp.24-28
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• 2003

Purpose: We aim to research the difference of abdominal temperature in dysmenorrhea patients comparing with that of normal person. Metholds: We selected the 49 dismenorrhea patients as study group and 54 normal persons as control group, excluding the patients who have dermatitis, ared over 70 or under 10. and have extreme obesity. We compared the 4 points(Rt and Lt Gimun(LR14) and Guirae(ST29)) in thd abdomen of both group, check the temperature of those points with DITI(Dorex, DTI-16UTI) to compare the temperature difference with each other. For statistics, we use independent T-test, SPSS 8.0 for windows. Results: The temperature difference between Rt and Lt Gimun which are in upper abdomen shows statistically significant result in study group. Conclusion: The dysmenorrhea patients show larger temperature difference between Rt and Lt points in upper abdomen than normal persons. In lower abdomen, the temperature between control and study group shows little difference.

• Coupled systems mechanics
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• v.8 no.3
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• pp.273-287
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• 2019

Elastoplastic analysis of an annular disc, being fully constrained on its outer rim and interacting with a purely elastic inclusion perfectly bonded with its inner rim, is conducted to study its plastic deformation and residual stress under thermal cycles. The system is termed the composite disc. Quasi-static plane-strain deformation is assumed, and the von Mises yield criterion with or without the Ludwik hardening rule is adopted in our finite element calculations. Effects of multiple material properties simultaneously being temperature dependent on the plastic behavior of the composite disc are considered. Residual stress is analyzed from a complete loading and unloading cycle. Results are discussed for various inclusion radii. It is found that when temperature dependent material properties are considered, the maximum residual stress may be greater than the maximum stress inside the disc at the temperature-loaded state due to lower temperature having larger yield stress. Temperature independent material properties overestimate stresses inside materials, as well as the elastic irreversible temperature and plastic collapse temperature.

• Computers and Concrete
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• v.23 no.5
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• pp.321-327
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• 2019

Experimental isotherm compressive tests show that concrete behaviour is dependent on temperature. The aim of such tests is to reproduce how concrete will behave under environmental changes within a moderate range of temperature. In this paper, a novel constitutive elastic damage behaviour law is proposed based on a free energy with an apparent damage depending on temperature. The proposed constitutive behaviour leads to classical theory of thermo-elasticity at small strains. Fixed elastic mechanical characteristics and fixed evolution law of damage independent of temperature and the material volume element size are considered. This approach is applied to compressive tests. The model predicts compressive strength and secant modulus of elasticity decrease as temperature increases. A power scaling law is assumed for specific entropy as function of the specimen size which leads to a volume size effect on the stress-strain compressive behaviour. The proposed model reproduces theoretical and experimental results from literature for tempertaures ranging between $20^{\circ}C$ and $70^{\circ}C$. The effect of the difference in the coefficient of thermal expansion between the mortar and coarse aggregates is also considered which gives a better agreement with FIB recommendations. It is shown that this effect is of a second order in the considered moderate range of temperature.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1527-1533
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• 2011

The reaction of gas-phase atomic hydrogen with oxygen atoms chemisorbed on a silicon surface is studied by use of the classical trajectory approach. We have calculated the probability of the OH formation and energy deposit of the reaction exothermicity in the newly formed OH in the gas-surface reaction H(g) + O(ad)/Si${\rightarrow}$ OH(g) + Si. All reactive events occur in a single impact collision on a subpicosecond scale, following the Eley-Rideal mechanism. These events occur in a localized region around the adatom site on the surface. The reaction probability is dependent upon the gas temperature and shows the maximum near 1000 K, but it is essentially independent of the surface temperature. The reaction probability is also independent upon the initial excitation of the O-Si vibration. The reaction energy available for the product state is carried away by the desorbing OH in its translational and vibrational motions. When the initial excitation of the O-Si vibration increases, translational and vibrational energies of OH rise accordingly, while the energy shared by rotational motion varies only slightly. Flow of energy between the reaction zone and the solid has been incorporated in trajectory calculations, but the amount of energy propagated into the solid is only a few percent of the available energy released in the OH formation.