• Journal of the Korean Ceramic Society
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• v.21 no.4
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• pp.341-348
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• 1984

$BaTiO_3$ and $SrTiO_3$ were mixed with the mole ratio of 35:65， 50:50 and 65:35 and heated at 1100~120$0^{\circ}C$ for 1~64 hours. The dielectrics of $BaTiO_3$-$SrTiO_3$ system were investigated as a function of amount of solid solution formed. The dielectric constant was increased and Curie temperature was shifted to higher temperature with increasing of heating of soaking time for the same composition and heating temperature. This can be explained by the homogeneous distribution of $Ba^{2+}$ and $Sr^{2+}$ ion in the $BaTiO_3$ system. The Curie temperature was shifted to lower temperature with increasing $SrTiO_3$ in the $BaTiO_3$-$SrTiO_3$system because of decreasing the lattice constant.

• Journal of Aerospace System Engineering
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• v.2 no.2
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• pp.42-45
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• 2008

Under the non-operating exposure condition in the hot area, the T-50 cockpit temperature is expected over the requirement according to T-50 environmental criteria. So it is necessary to protect the cockpit from the high temperature condition during the non-operating exposure because the high temperature of the cockpit may result in the cockpit equipment malfunction. In this study, the transparency coating is selected as the method for protecting the cockpit from the high temperature exposure and analyzed the effect on the cockpit heat load attenuation. Some kinds of cockpit coating were reviewed and selected and the analysis was performed about the effect before and after coating application under 1% hot day condition based on the T-50 FSD hot soaking test data. The result of analysis show transparency coating is so effective to attenuate the heat load of T-50 cockpit.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.299-302
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• 2000

RTD temperature sensor is a thermoresistor which uses the liner dependence of the resistance of the sensing material on the temperature, and has good stability and sensibility, so it can be used in highly precise temperature measurement. In this study RTD sensor was fabricated using Pt thin film. The Pt thin film was deposited on alumina using DC-Sputter, and annealed with various temperature. Through the experiments of XRD, AFM, 4-point probe, the surface structure of the thin film with annealing conditions and their effects on the electrical resistance were investigated. RTD with serpentine pattern was fabricated using Lift-off and resistance-temperature characteristics were studied.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.735-740
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• 2014

The study investigated the roast color formation properties of ginseng upon soaking in threonine/sucrose solution followed by roasting. To determine operational parameters, including threonine concentration ($X_1$, 0.1~0.9%), sucrose concentration ($X_2$, 1.0~3.0%), and roasting temperature ($X_3$, $130{\sim}170^{\circ}C$), response surface methodology was applied to monitor color properties, including brown color intensity, Hunter's colors, and organoleptic color. Coefficients of determinations ($R^2$) of the models were above 0.8758 (P<0.05) in terms of brown color intensity and Hunter's color parameters. Brown color intensity of roasted ginseng extract was maximized in 0.70% threonine and 2.32% sucrose soaking solution under roasting conditions of 25 min at $166.03^{\circ}C$. a values of roasted ginseng were maximized in 0.74% threonine and 2.19% sucrose soaking solution under roasting conditions of $165.40^{\circ}C$. b values of roasted ginseng were maximized in 0.61% threonine and 2.28% sucrose soaking solution under roasting conditions of $159.16^{\circ}C$. The maximum organoleptic color score of roasted ginseng extract was 7.27 in 0.53% threonine and 1.01% sucrose soaking solution under roasting conditions of $146.96^{\circ}C$.

• Journal of Korean Society of Forest Science
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• v.3 no.1
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• pp.15-17
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• 1963

1) An experiment was made at the newly constructed glass house of Chun chan Agriculture callege to find out facts about the late-raising of Cortinellus edodes (Berk) Ido et Imai during the winter season. 2) The host timbers used in this experiment were Quercus Serrata Thumb and Quercus crispulo BI.; 5 years old each, the diameter ranging from 6cm to 17cm, dividing them into 12 diameter groups with 10 timbers in each group. The total number of timbess was 240 in two blocks. 3) As the pre-treatment of host timber, the autumn generation in 1962 was inhibited, and before being put into the glass-house, they were stimulated of generation for 3 days after 3 days, water-soaking. 4) The temperature control was made by using two coal stoves and the humidity control by spraying and two full water tanks. During cloudy weather and night, the green house was covered to preserue constant temperature of $5^{\circ}C{\sim}10^{\circ}C$. 5) The result; Quercus Serrata Thumb. with lesser diameter than 9cm showed no generation either in as big timber as one with diameter 11 cm. On the other hand, too big timbers showed low rate of generation; the reason, at a guess, is the too short period of cultivation and insufficient water soaking and inappropriate temperature. 6) The most standard size of host timber was found out be those with diameter 12cm~15cm in Quercus serrata Thumb, and those with diameter 14cm~17cm in Quercus crispula BI. Quercus crispula seemed to have slightly greater efficiency of generation than Quercus Serrata Thumb., but it could not be concluded as "decisive". Lastly, the host timber used in this experiment were old and the rate of generation was low as a whole.

• Journal of the Korean Ceramic Society
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• v.18 no.4
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• pp.257-261
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• 1981

The tendency of glass containing titanium-dioxide to separate into two phases can be attributed to a change of the coordination number of titanium from six to four on increase of temperature and to "freezing" of the high temperature four fold coordination on cooling of the melt. Addition of TiO2 to the basic glass 8.7 $Na_2O$ 22.4B2O3 68.9 $SiO_2$ was varied 5 to 25 parts. The phase separation in the temperature range of transformation was examined with each heating temperature and soaking time. As the experimental results, the most distinct phase separation were obtained from alkali extraction method when $TiO_2$ was added 15 parts. The apparant activation energy was 30.5 Kcal/mole by alkali extraction method derived from Arrhenius plots.ius plots.

• Journal of the Korean Ceramic Society
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• v.26 no.6
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• pp.843-849
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• 1989

Effect of Bi2O3/Li2CO3 on low temperature sinteirng and dielectric property of BaTiO3 ceramics has been investigated. For the specimen sintered at 110$0^{\circ}C$, it was densified to 96% of BaTiO3 theoretical density by the addition of 1.0-1.25w/o Bi2O3/Li2CO3. Maximum dielectric constant increased and Curie temperature lowered with the increase of Bi2O3/Li2CO3 content, which probably can be explained by thne substitution of Bi3+, Li1+ on BaTiO3 lattice. The volatilization of Li1+, resulting from the increase of soaking time at 110$0^{\circ}C$ leads to the increase of Curie temperature and tetragonality of the specimen.

• Corrosion Science and Technology
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• v.3 no.4
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• pp.172-177
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• 2004

Biaxially oriented polyethylene terephthalate copolymer(BO - PET)film laminated aluminiums have been applied for chip condenser case. The BO PET film is characterized by high molecular which gives high corrosion resistance, good adhesion and high heat resistance. The higher orientation lowers formability of the film. So, optimum orientation has to be controlled during the laminating process. And to confirm the adhesion between BO PET and aluminium and to guarantee the formability of PET laminated aluminums, we have controlled the chromium oxides weight on the aluminium and laminating condition ( laminating temperature, soaking temperature and lag time after nip roll and quenching conditions) This paper discusses the effect of the laminating conditions on the formability of laminated aluminums. As results, it is clear that the orientation of the BO PET film decreased with an increase in the strip temperature. When the film temperature is over the melting point of the film, its orientation drastically decreased.

• Journal of the Korean Ceramic Society
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• v.21 no.2
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• pp.135-142
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• 1984

The electrical conductivity of compositions in the system $CaO-ZrO_2$ has been measured by 2-probe tech-nique in the temperature range 350~75$0^{\circ}C$. The composition of maximum conductivity in this system is within the cubic solid-solution region close to low-calcia cubic solid-solution phase boundary. The results are as follows : 1) The maximum conductivity was found 13mol CaO in zirconia. 2) As the CaO content was increased from 13 to 21 mol% the electrical conductivity decreased for any given temperature and the activation energy increased. 3) As the firing temperature and soaking time was increased the electrical conductivity increased and activation energy decreased.

• Journal of the Korean Wood Science and Technology
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• v.12 no.4
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• pp.12-18
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• 1984

Soaking treated in 20% aqueous solutions of $(NH_4)_2SO_4$, $NH_4H_2PO_4$, $(NH_4)_2HPO_4$, $Na_2B_4O_7-H_3BO_3$(60:40) and Minalith, the mixed salts for 9 hrs. the wet 3.5mm meranti (Parashorea spp.) plywoods were press-dried at 90, 120 and $150^{\circ}C$ and put to static bending test to examine the influence of redrying temperature on the strength of fire-retardant treated plywoods ill flexure. While water-soaking treatment (control) showed serious reduction in Stress at proportional limit, MOE, MOR, Work per unit volume at $150^{\circ}C$, all the fire-retardant treatments maintained bending strength even at $150^{\circ}C$ and showed rather increased values in case of some chemicals. In view of drying rate and maintenance of strength, the most pertinent platen temperature was $150^{\circ}C$ and Borax-Boric acid was the predominant fire-retardant in this study.