• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.301-304
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• 1988

A pH-meter has been newly developed by using on ISFET as the ion sensing element. The performance characteristics of the developed pH-meter have been investigated and confirmed to be used practically. The stable operation and the temperature compensation were stressed in this study.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07a
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• pp.451-454
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• 2002

A silicone rubber has been used so many dielectric materials for extremely high voltage(EBW) electric appliances. The reason why it is very stable in the thermal, mechanical and electrical environment. In this paper, we have studied the dependence of dielectric characteristics of silicone rubber on frequency-dependent variation. The dielectric characteristics were measured in the temperature range of 25[$^{\circ}C$] and 150[$^{\circ}C$]. Also we measured in the voltage range of 1[V] and 20[V]. The energy of activation on the dielectric loss obtained 2.44[kcal/mol], 2.1[kcal/mol], 1.63[kcal/mol] and 1.57[kcal/mol] by appling respectively.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1683-1685
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• 2003

MgO is making an important role not only as a protective layer but also improves the discharge characteristics at AC PDP. Until now, the substitute of protective layer, MgO has been studied in many ways, but it's too difficult to get a new substitute as stable as MgO. But some problems has been advanced at the discharge characteristics of MgO on high temperature. So we studied the discharge characteristics of impure MgO with $SiO_2$ doped.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.1
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• pp.95-104
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• 2003

The objective of this work is to investigate the turbulent reacting flow in a three dimensional combustor with emphasis on thermal NO emission through a numerical simulation. Flow field is analyzed using the SIMPLE method which is known as stable as well as accurate in the combustion modeling, and the finite volume method is adopted in solving the radiative transfer equation. In this work, the thermal characteristics and NO emission in a three dimensional combustor by changing parameters such as equivalence ratio and inlet swirl angle have investigated. As the equivalence ratio increases, which means that more fuel is supplied due to a larger inlet fuel velocity, the flame temperature increases and the location of maximum temperature and thermal NO has moved towards downstream. In the mean while, the existence of inlet swirl velocity makes the fuel and combustion air more completely mixed and burnt in short distance. Therefore, the locations of the maximum reaction rate, temperature and thermal NO were shifted to forward direction compared with the case of no swirl.

• Journal of Pharmaceutical Investigation
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• v.21 no.3
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• pp.161-170
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• 1991

The storage stabilities of immunoliposomes incorporated with variable amounts of ganglioside $G_{M1}$ were investigated as a function of time. temperature. and composition by observing absorbance of visible light and calcein release. In the column chromatographe, the layer of unsaturated PE(dioleoylphosphatidylethanolamine : DOPE). unable to form stable liposomes at physiological temperature and pH, were formed when palmitoyl-immunoglobulin G(IgG) $(2.5{\times}10^{-4}\;mol/DOPE\;mol)$ added. The incorporation of ganglioside $G_{M1}$ into immunoliposome. enhanced the stabilities of bilayers during the extended period of storage. The turbidities of immunoliposomes coated with ganglioside $G_{M1}$ exhibited the maximum near 20 mol% $G_{M1}/DOPE$ mol. probably because of the disturbance of the bilayer characteristics, i.e., layer transition or reorientation of interaction sites. At low temperature. the higher stability was achieved than at elevated temperatures. After one week of storage. the redispersed liposomal solutions at lower temperatures maintained the original elution patterns in chromatography but broader distribution at elevated temperatures. During the storage, it is suggested the aggregation is the more dominant phenomena for liposomes kept at $5^{\circ}C$ than the fusion. while he fusion is at elevated temperatures.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.2
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• pp.55-63
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• 2008

We investigated characteristics of temperature variation in urban and suburban areas(e.g., paddy field, upland, park, residential area) and urban heat island(UHI) during winter(December 2005 to February 2006). The daily maximum air temperature was not significantly different between suburban and urban areas, whereas the daily minimum air temperatures were significantly lower in the suburban areas than that in the residential area. The wind speed in the urban park(0.3 m/s) was much lower than that in the paddy fields(2.3 m/s), likely due to an urban canopy layer formed by high buildings. The UHI intensity was represented by differences in daily minimum temperatures between urban residential and paddy field areas. The UHI intensity($4.1^{\circ}C$) in winter was larger than that($2.6^{\circ}C$) in summer. This may be because a stable boundary layer develops in the winter, and thereby this inhibits diffusion of heat from surface.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.222.2-222.2
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• 2012

Camera for QUasars in EArly uNiverse (CQUEAN) is an optical CCD camera attached to the 2.1m Otto Struve telescope at the McDonald Observatory, USA. CCD output signal contains the electrons generated by photoionization of incident light and thermal ionization. Therefore reliable photometric result can be obtained only under the stable condition of CCD thermal properties. We investigated the temperature dependency of the various characteristics of CQUEAN CCD chip, including bias level, dark level, gain, and quantum efficiency (QE), with the CQUEAN observation and calibration data obtained during 2012 May run. We discuss the environmental effects, i.e., ambient temperature, as well as CCD temperature on the stability of its characteristics.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.1
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• pp.41-47
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• 1998

The (Sr$_1$-\ulcorner.Ca\ulcorner)TiO$_3$(0.05 x 0.2) ceramics were fabricated to form semiconducting ceramics by sintering at about 1350[$^{\circ}C$] in a reducing atmosphere($N_2$gas). After being fired in a reducing atmosphere, metal oxides(CuO) was painted on the both surface of the specimens to diffuse to the grain boundary. The capacitance changes slowly and almost linearly in the temperature region of -40~+85[$^{\circ}C$]. The capacitance characteristics appears a stable value within $\pm$10[%]. According to increase of the frequency as a functional of temperature, all specimens used in this study showed the dielectric relaxation, and the relaxation frequency was above 10\ulcorner[Hz]. The capacitance is almost unchanged below about 20[V] but it decrease slowly over 20[V]. The voltage-current characteristics of specimens observed in the temperature range of 25~125[$^{\circ}C$] as the current increased appears that it is due to space charge condensed to interface between grain and grain boundary.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.5
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• pp.1108-1114
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• 2001

The fatigue crack propagation behavior of the SA516-Grade 70 steel which is used for pressure vessels was experimentally examined under the condition of at room temperature, $150^{\circ}C$, $250^{\circ}C$ and $370^{\circ}C$ with stress ration of R=0.1 and 0.3. The fatigue crack propagation rate , da/dN, related with the stress intensity factor range, $\vartriangle$N, was influenced by the stress ration within the stable growth of fatigue crack(Region II) with an increase in $\vartriangle$N. The resistance to the fatigue crack growth at high temperature is higher in comparison with that at room temperature, and the resistance attributed to the extent of plasticity-induced by compressive residual stress according to the cyclic loads. Fractographic examinations revels that the differences of the fatigue crack growth characteristics between room and high temperatures are mainly explained by the crack and oxide-induced by high temperature.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.10a
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• pp.147-153
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• 2000

The fatigue crack propagation behavior of the SA516/70 steel which is used for pressure vessels was examined experimentally at room temperature, $150^{\circ}C$, $250^{\circ}C$ and $370^{\circ}C$ with stress ratio of R=0.1 and 0.3. The fatigue crack propagation rate da/dN related with the stress intensity factor range $\Omega\textrm{K}$ was influenced by the stress ratio within the stable growth of fatigue crack(Region II) with an increase in $\Omega\textrm{K}$. The resistance to the fatigue crack growth at high temperature is higher in comparison with that at room temperature, and the resistance attributed to the extent of plasticity-induced by compressive residual stress according to the cyclic loads. Fractographic examinations reveal that the differences of the fatigue crack growth characteristics between room and high temperatures are mainly explained by the crack closure and oxide-induced by high temperature.