• Journal of the Korean Ceramic Society
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• v.31 no.1
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• pp.97-103
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• 1994

The influence of ground petroleum coke, preheat-treated at temperatures ranged of 150~35$0^{\circ}C$, was studied. It has been found that the coke powder preheat-treated at the temperature of 175$^{\circ}C$ has been spherical-shaped in grinding and have showed the highest strength and density in sintering. The coke powder was also the best for the binding force and the (H/C) values showed 0.45 at the above temperature.

• Electrical & Electronic Materials
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• v.1 no.1
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• pp.70-77
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• 1988

This paper describes the influence of the electrode materials, moisture content, electrolyte density, temperature, surface state, ion absorbent on the C.T.I of phenolic resin by the I.E,C, 112 method. C.T.I are increased for electrode materials with low hydrogen overvoltage and high soluble point. Increusing moisture content of samples increased by logarithmical on the droplet number to tracking breakdown. Increasing electrolyte temperature region above 70-80(.deg.C) decreased hydrogen over-voltage, following the density changes are decreased by C.T.I=1/aD$^{2}$-bD+C.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.5
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• pp.463-468
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• 2002

Influence of increased temperature on the standard metabolism in three species of marine bivalves, Crassostrea gigas, Ruditapes philippinarum and Mytilus edulis, acclimated to seasonal water temperatures and collected from the south coast of Korea, were examined in the laboratory. The standard oxygen consumption and filtration rates in the 3 species were measured respectively at the experimental temperature, 4, 7 and 10$^{\circ}C$ or 3, 6 and 9$^{\circ}C$ higher than the mean seasonal water temperature. When the experimental temperatures were higher than the seasonal water temperature, the rates of C. gigas decreased in autumn and spring, and increased In winter, while there was thermal stress in summer. The rates of R. philippinarum increased in spring when the experimental temperatures were 3$^{\circ}C$ and 6$^{\circ}C$ higher than the seasonal water temperature, but the rates increased in autumn and winter when the experimental temperature was even 9$^{\circ}C$ higher than the seasonal water temperature. In summer. metabolic activities of R. philippinarum decreased significantly at temperature higher than acclimation temperature. The rates of M. edulis increased in spring when the experimental temperatures were 3$^{\circ}C$ higher than the seasonal water temperature but the rates were stressed by the increased temperature above 3$^{\circ}C$. In winter, increased temperature did not affect the metabolic activities of M. edulis. These results suggested that the standard metabolism of the three marine bivalves in summer was stressed by the increased temperature, whereas the metabolism was activated in winter.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.9 no.2
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• pp.45-53
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• 2005

This paper investigates the influence of thermal conductivity and variable viscosity on the problem of micropolar fluid in the presence of suction or injection. The fluid viscosity is assumed to vary as an exponential function of temperature and the thermal conductivity is assumed to vary as a linear function of temperature. The governing fundamental equations are approximated by a system of nonlinear ordinary differential equations and are solved numerically by using shooting method. Numerical results are presented for the distribution of velocity, microrotation and temperature profiles within the boundary layer. Results for the details of the velocity, angular velocity and temperature fields as well as the friction coefficient, couple stress and heat transfer rate have been presented.

• Corrosion Science and Technology
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• v.13 no.2
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• pp.48-55
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• 2014

Influence of annealing temperature on the microstructure and resistance to pitting corrosion of the hyper duplex stainless steel was investigated in acid and neutral chloride environments. The pitting corrosion resistance is strongly dependent on the microstructure, especially the presence of chromium nitrides ($Cr_2N$), elemental partitioning behavior and volume fraction of ferrite phase and austenite phase. Precipitation of deleterious chromium nitrides reduces the resistance to pitting corrosion due to the formation of Cr-depleted zone. The difference of PREN (Pitting Resistance Equivalent Number) values between the ferrite and austenite phases was the smallest when solution heat-treated at $1060^{\circ}C$. Based on the results of electrochemical tests and critical crevice temperature tests, the optimal annealing temperature is determined as $1060^{\circ}C$.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.4
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• pp.625-632
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• 2012

Optimization of process parameters in polymer extrusion is an important task to reduce manufacturing cost. To determine the optimum values of the process parameters, it is essential to find their influence on the strength of polymer breathable thin film. The significance of six important process parameters namely, extruder cylinder temperature, extruder speed, extruder dies temperature, cooling roll temperature, stretching ratio, stretching roll temperature on breathable film strength of polymer extrusion was determined. Moreover, this paper presents the application of Taguchi method and analysis of variance (ANOVA) for maximization of the breathable film strength influenced by extrusion parameters. The optimum parameter combination of extrusion process was obtained by using the analysis of signal-to-noise ratio. The conclusion revealed that extruder speed and stretching ratio were the most influential factor on the film strength, respectively. The best results of film strength were obtained at higher extruder speed and stretching ratio.

• Fisheries and Aquatic Sciences
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• v.1 no.1
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• pp.79-81
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• 1998

To investigate the influence of originated host and water temperature on the infectivity and growth of Microcotyle sebastis, juveniles of Schlegel's black rockfish (Sebastes schlegeli) were exposed to the eggs of M. sebastis originated from. Schlegel's black rockfish and black rockfish (Sebastes inermis) at $10^{\circ}C$ and $10^{\circ}C$. There were significant differences between the two isolates in the infectivity of eggs, and the growth of worms. The growth of M. sebastis was significantly affected by water temperature, and worms grew faster in $20^{\circ}C$ than in $10^{\circ}C$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.2
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• pp.73-78
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• 2003

The influence of calcination temperature on the pore structure of freeze dried silica gel derived from tetraethyl orthosilicate (TEOS) was investigated using $N_2$adsorption and mercury intrusion techniques. Freeze dried material contained not only 4-6 nm sized mesopores and 6-10 $\mu\textrm{m}$ sized macropores, but minor micropores. The change of pore structure due to the increase of calcination temperature was dependant upon the degree of densification.

• Journal of the Korean Society of Tobacco Science
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• v.26 no.1
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• pp.50-56
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• 2004

The quality of burley leaf tobacco was affected by various toasting conditions. In this study, we determined main factor to influence the quality of burley tobacco on toasting and established proper toasting condition to improve the quality of toasted tobacco. Our results indicated that the main factor to influence the quality of burley tobacco was the amount of treatment and 3rd drying zone temperature. We also found that the proper toasting conditions to improve the quality of toasted tobacco and reduce the smoking irritation were moisture content (34 %), amount of treatment (1,520kg/hr), 1st drying zone temperature (135$^{\circ}C$), 2nd zone drying temperature(145$^{\circ}C$) and 3rd zone drying temperature (147$^{\circ}C$).

• Journal of the Korean Home Economics Association
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• v.24 no.3
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• pp.59-67
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• 1986

The heat of sewing needle is generated through the friction during the needle penetration into and withdrawal from fabrics. Therefore, effects of sewing condition for knitted fabric on the heat generation of needle was examined. The needle size was not the large influence factor of heat generation of needle but the needle point shape significantly affects needle temperature. And the super needle coated with fluoro resin had more effect on reducing the heat of needle. The decrease of sewing speed and the increase of stitch rate had more effect on the reduction in needle temperature. Also the Influence of a sewing thread on the needle temperature was very large compared with bare needle. As expected, an increase in the number of fabric layers result in higher needle temperature.