• Korean journal of food and cookery science
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• v.6 no.4 s.13
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• pp.9-14
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• 1990

The emlsifying properties of small red bean protein isoates were evaluated through their emulsion capacity and stability of the resulting emulsions. The influence of pH, Sodium Chloride and heat treatment on the efficiency of small red bean protein isolates as emulsifying agents was studied. The surface hydrophobicity (So) of small red bean protein islates also examined. The results were obtained as follows; 1. The emusion capacity of small red bean protein isolates was high at pH 11, low at pH 3 and decreased by heat treament. With addition of NaCl, emulsion capacity decreased steadily and showed lowest value when 0.2M NaCl was added. 2. The emulsion stability at pH 4.5 and heat treatment over $60^{\circ}C$ decreased emulsion stability at pH 4.5. When NaCl was added, emulsion stability was generally increased. 3. The surface hydrophobicity of small red bean protein isolates showed the highest value at pH 3 and lowest at pH 11 and increased as the heating temperature increased When 0.2 M NaCl was added, surface hydrophobicity also increased at pH 4.5.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.7
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• pp.317-323
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• 2001

We investigated the stability of cryocooler-cooled high-temperature superconducting (HTS) coils by using a computer program based on FEM. In this study, the current at which "thermal runaway" occurs, which depends on the relationship between the cooling power of the cryocooler and the heat generation in HTS coils, was adopted as a stability criterion of cryocooler operating HTS coils. It was shown that cryocooler-cooled HTS coil was stable in operating current above the critical current from the numerical analysis results by HTS model coil. And also, if we efficiently remove the heat generation from HTS coils by potimizing heat drain, the ramp-rate limitation can be mitigated because the effect of AC loss by the current rise was too small. Furthermore, in the case of pulsed operation; the HTS model coil is ramped from zero to the peak value in one second and back to zero current in one second, such as the operation of SMES device, the peak value of poerating current is 1.5-2 times greater than that of the thermal runaway current.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.12 s.243
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• pp.1352-1359
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• 2005

Unsteady simulations were performed to investigate the flame structure and the dynamic behavior of a premixed flame exposed to the wall heat loss. A 3-step global reaction mechanism was adopted in this study. Simulations were performed for two tube combustors with inner diameters($d_i$) of 1mm and 4mm. The material of tube combustor was assumed to be a Silicon Nitride($Si_{3}N_4$). The heat loss from the outer tube wall was controlled by adjusting the amount of convective and radiative heat loss. A conical premixed flame could be stabilized inside a tube of $d_i=4mm$. The flame stability inside a tube of $d_i=4mm$ combustor was not much sensitive to the amount of heat loss. In case of a tube of $d_i=1mm$, an oscillating flame was observed in very low heat loss condition and a flame could not be sustained in realistic heat loss condition.

• Carbon letters
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• v.8 no.2
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• pp.127-133
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• 2007

In this study, commercially available pitch-based carbon fibers of general grade were post-heat-treated using a boxtype high temperature furnace at $1800^{\circ}C$, $2000^{\circ}$, $2200^{\circ}C$, and $2400^{\circ}C$, respectively. The fundamental characteristics of each heat-treated carbon fibers were investigated in terms of chemical composition, morphology, thermal stability, X-ray diffraction, single filament tensile test, and electrical resistivity. The result showed that the fiber properties were significantly influenced by the post-heat-treatment, indicating the greater effect with increasing treatment temperature. The carbon contents, thermal stability, and tensile properties of the carbon fibers used here were further increased by the post-heat-treatment, whereas the d-spacing between graphene layers and the electrical resistivity were reduced with increasing post-heat-treatment temperature.

• Honam Mathematical Journal
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• v.33 no.4
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• pp.467-485
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• 2011

We consider the Hyers-Ulam-Rassias stability problem $${\parallel}u{\circ}A-{\upsilon}{\circ}P_1-w{\circ}P_2{\parallel}{\leq}{\varepsilon}({\mid}x{\mid}^p+{\mid}y{\mid}^p)$$ for the Schwartz distributions u, ${\upsilon}$, w, which is a distributional version of the Pexider generalization of the Hyers-Ulam-Rassias stability problem ${\mid}(x+y)-g(x)-h(y){\mid}{\leq}{\varepsilon}({\mid}x{\mid}^p+{\mid}y{\mid}^p)$, x, $y{\in}\mathbb{R}^n$, for the functions f, g, h : $\mathbb{R}^n{\rightarrow}\mathbb{C}$.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.89-91
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• 1996

In dry-winding(unfilled) superconducting magnets, the behavior of liquid helium occupying the extremely small void space within the winding is contributed as a primary factor for transient stability of magnets. Therefore, numerical experiments have been carried out concerning the influences of transient heat transfer of liquid helium ocupying the void space in the winding and thermal properties of insulation at the conductor surface on the transient stability of magnets, by using three-dimensional finite element method(FEM). In this paper, we are going to consider three different cases for heat transfer characteristics of liquid helium to observe the influences of the rest of liquid helium in void space within the winding on the transient stability.

• 한국연소학회:학술대회논문집
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• 2001.11a
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• pp.97-103
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• 2001

The characteristics of flame stability have been studied experimentally using a slot burner. The blowout conditions of a fuel-lean premixed laminar flame, which is located in the middle of fuel-rich premixed laminar flames, are identified for propane, ethylene, and methane flames. The fuel-rich flames could stabilize the fuel-lean flame for the equivalence ratio as low as 0.2. The laminar flame speed along with the heat release rate is likely to be the important factor in stabilizing a fuel-lean flame. The increase of heat release rate on a fuel-rich flame lowers the equivalence ratio limit for the stable fuel-lean flames. The stability of fuel-lean flames, however, was not sensitive to the equivalence ratio of a fuel-rich flame.

• Electrical & Electronic Materials
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• v.10 no.9
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• pp.895-900
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• 1997

A Quench in cable-in-conduit (CIC) conductors is often initiated by a disturbance such as strand motion that generates a highly localized normal zone in a strand or a few strands of the CIC conductors. The localized normal zone causes current and heat transfer between a disturbed strand and neighboring strands. Electrical and thermal contact characteristics between strands thus have an effect on the transient stability of the CIC conductors. In this paper the effect of contact characteristics between strands on the CIC conductor stability is presented based on the measured heat transfer characteristics of supercritical helium (SHe) for the local heating. The quench and recovery processes of the strands for the abrupt and highly localized disturbance are analyzed at the boundary between quench and recovery.

• Journal of the Korean Society for Heat Treatment
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• v.23 no.5
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• pp.239-244
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• 2010

Influence of Zr addition on grain stability at elevated temperatures has been investigated for extruded pure Mg and Mg-0.25%Zr alloy. The grain size of pure Mg increases rapidly with increasing annealing temperature when isochronally annealed for 60 min from 573 to 773 K, whereas the grains are stable up to 723 K for the Zr-containing alloy. The activation energies for grain growth ($E_g$) at this temperature range were determined as 75.3 and 105.9 kJ/mole for the pure Mg and Mg-0.25%Zr alloy, respectively. TEM observations on the annealed Mg-Zr samples revealed that higher thermal stability and higher activation energy for grain growth resulting from Zr addition in Mg may well be associated with the restriction of grain growth by nano-sized Zr particles distributed in the microstructure.

• Applied Biological Chemistry
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• v.19 no.2
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• pp.75-81
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• 1976

High ionic strength is expected to enhance dissociation of Ca-DPA from spores and to contribute to a detrimental effect on spore stability or on spore heat resistance with a combined treatment of gamma-radiation. From this study, this hypothesis has become apparent as as follows; 1) Ca-DPA dissociation contributes to loss of stability of bacterial spores with respect to heat resistance, survival during storage, and 2) the cytoplasmic membrane plays a role in maintaining the stability of DPA-Ca-spore complex, apparently by serving as a permeability barrier.