• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.1
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• pp.62-66
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• 2003

Mass consumption of the surplus onion in the period of harvesting season by processing to various value-added functional food products would be one of the counterplot for stable market. This study was to develop functional sponge cakes with addition of onion powder, using physiochemical properties and sensory evaluation. The specific gravity and viscosity tended to increase according to the addition of onion powder. The water content was highest mark on the 4% onion powder added-cake. The color of lightness, yellowness, and redness of cake crust tended to decrease with the addition of onion powder. The addition of onion powder showed decrease in lightness and yellowness and increase in redness of cake crumb. The specific loaf volume was superior with the addition of 4% onion powder. The resilience, fracturability and adhesiveness showed a difference from the control. Sensory evaluation of cake indicated that addition of onion powder especially at the level of 2, 4%, enhanced appearance flavor, mouth feeling, and overall acceptability.

• Magazine of the Korea Concrete Institute
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• v.9 no.2
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• pp.145-151
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• 1997

In concrete mix design we need the informations of the codes, the specifications, and the experiences of experts. However we can't consider all factors regarding concrete mix design. The final acceptance depends on concrete quality control test results. In this process we meet the uncertainties of materials. temperature, site environmental situations, personal skillfulness. and errors in calculations and testing process. Then the mix design adjustments must be made. Concrete mix design and adjustments arc somewhat complicated, time-consuming. and uncertain tasks. In this paper, as a tool to minimize the uncertainties and errors the neural network is applied to the concrete mix design. Input data to train and test the neural network are obtained numerically from the results of design following the concrete standard specifications of Korea. The 28-days compressive strengths which are variate according to the uncertainties and errors are considered. The results show that neural networks have a strong potential as a tool for concrete mix design.

• Journal of the Korean Chemical Society
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• v.41 no.8
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• pp.385-391
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• 1997

Diffusion Coefficient$(D_0)$ and electrode reaction rate Constant$(K_0)$ of Co$(dimethyl bipyridine)_3(ClO_4)_2$ were determined by cyclic voltammetry and chronoamperometry. It was also investigated that the effects of solvent, concentration, and scan rate, etc. on the diffusion coefficient and the temperature effect on the rate constant. The peak currents and diffusion coefficients were dcreased as increasing the viscosity of solvent. Diffusion coefficient was $5.54{\times}10^{-6 }cm^2/sec$ and the reaction rate constant was $2.39{\times}10^{-3 }/s$ at 25$^{\circ}C$. The thermodynamic parameters such as ${\Delta}G^{\neq},\;{\Delta}H^{\neq},\;and\;{\Delta}S$ were calculated from plotting the reaction rate constants versus the solution temperatures. This compound was shown the catalytic effect on the oxygen reduction that the reduction peak current of oxygen was greatly enhanced and the peak potential was shifted to +0.2 volt.

• Journal of the Korean Chemical Society
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• v.40 no.12
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• pp.748-755
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• 1996

The effects of temperature on the conformational properties of poly(ethylene oxide) (PEO) in aqueous and aqueous urea solutions are reported. The values of intrinsic viscosity and Huggins coefficients for the PEO dissolved in water and urea/water mixtures (urea concentration 0.2, 1, and 2 M) were obtained using a viscometry method and discussed with respect to the change of water structure. At low temperatures (below 22 $^{\circ}C)$, the PEO-water interaction is favorable and the chain can be extended, whereas at higher temperatures (above 24 $^{\circ}C)$, it is less favorable and the chain can be contracted by a hydrophobic hydration, i.e., the PEO-water interaction becomes to be unfavorable with the increase in temperature. As the urea is added to the system, the PEO chain can be more extended and huged by the perturbation of the structured water originating from the unfavorable PEO-water interaction. The effect of temperature on the intrinsic viscosity values shows an Arrhenius behavior. The activation energies of the viscous flow were obtained and discussed.

• Korean Journal of Environment and Ecology
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• v.21 no.5
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• pp.442-448
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• 2007

This study was carried out to assess the improved aspects of ecological conditions in a small stream, where eco-technological restorations such as gabion-crib mattress arrangement and soil-arresting wicker fence work had already been made up to stabilize the physically and ecologically damaged streambank. Six metrics by diatoms including species richness, Shannon diversity, saprobic index by DAIpo, percent sensitive diatoms, percent of Achnanthes minutissima, dominant index were analysed to assess the ecological integrity of small stream. By generalizing the changed values of six metrics on the stream flow from upper point(ST.1) to lower point(ST.3), it was found that the effect value of ecological condition improvement went up to as much as 33.9% on the average. The results suggested that eco-technological restoration treatment applied to this study is considerably effective for preserving the ecological integrity of small stream.

• Asia-Pacific Journal of Business
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• v.1 no.1
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• pp.1-22
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• 2010

In theoretical term, cultural/institutional approach, the peculiarly of the later comers, such as Hong Kong, Korea, Twain, and the converging influence from Post-modernism underlie this paper. The first approach is influential in understanding the survival of many traditional values within most of the Hong Kong firms. The later comer one can be used to explain the fact that later comer enjoyed various synergy effects when their oriental values are combined with new practices. The last one is also quite useful for the explanation of why most modern firms exposed to a severe international competition adopted human resource management But problem is that these are subjected to severe criticism because of their downgrading nature against employees.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.64-70
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• 1998

Porous body was prepared from coal fly ash 70 wt%0clay 30 wt% slip using DCC(Direct Coagulated Casting) method. Effect of the specific gravity of the slip on the pore size and distribution of the sintered body was examined by the SEM observation of microstructure and mercury porosimetry measurement of the pore size distribution. Average pore size of the porous sintered body was about 2.5μm for all slips with specific gravity of 1.55, 1.60 and 1.65g/cm3, respectively. Sintered body prepared from the slip of specific gravity of 1.60g/cm3 have the narrowest pore size distribution. slip of specific gravity of 1.55g/cm3 shows broader pore size distribution due to slow gellation process. Slip of specific gravity of 1.65g/cm3 required large amount of deflocculant and showed large variation of the viscosity with addition of coagulant which resulted in very unstable slip properties.

• Polymer(Korea)
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• v.33 no.4
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• pp.384-388
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• 2009

The rheological properties of poly (acrylonitrile) (PAN) and cellulose acetate (CA) blend solutions in N,N-dimethyl formamide (DMF) were investigated in terms of temperature and blend composition. The solutions exhibited a very characteristic rheological behavior with variation of temperature. 8 wt% solution showed an increase of viscosity and a decrease of loss tangent as temperature was increased over the temperature range of 20 and $60^{\circ}C$. At $20^{\circ}C$ the physical properties of the solutions exhibited dependence on the blend composition. At 40 and $60^{\circ}C$, however, the effects of blend ratio on the physical properties notably diminished. The longer relaxation time at higher temperature indicated that the formation of physical structures resulting from intermolecular interactions was promoted with increasing temperature. The odd rheological responses were further elucidated by measuring of the physical properties of dilute solutions. The intrinsic viscosity of the solutions suggested that the coiled chain dimension was reduced with increasing temperature.

• Polymer(Korea)
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• v.37 no.1
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• pp.121-126
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• 2013

UV-curable high refractive index di-functional epoxy acrylate, 4,4'-thiodibenzenethiol diglycidyl ether diacrylate, was synthesized from acrylic acid and 4,4'-thiodibenzenethiol diglycidyl ether that was obtained by reacting 4,4'-thiodibenzenethiol and epichlorohydrin using a direct method (Taffy process). Its chemical structure was identified by $^1H$ NMR and FTIR. After its dilution with a reactive diluent, 2-phenoxythiol ethyl acrylate as 5, 10, 15, 20, and 30 wt% content, the relationship between their viscosity and refractive index was investigated. Their degree of cure decreased with increasing the amount of reactive diluent, and the refractive index of UV-cured film increased with increasing the degree of cure.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.545-550
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• 2003

The effect of ${\beta}-glucan$ on gelatinization of barley starch was studied. By the rapid visco-analyzer measurement, gelatinization of starch became rapid and viscosity increased largely on the RVA pattern by addition of ${\beta}-glucan$ to starch. The results of differential scanning calorimeter showed that molecular structure of starch was getting stabilized through shifting up of gelatinization temperature and increase in enthalpy by addition of ${\beta}$-glucan. X-ray diffraction pattern also showed the same results as differential scanning calorimeter. But it was revealed that addition of ${\beta}$-glucan to starch didn't affect characteristics such as microscopic observation, solubility, swelling power, and iodine binding properties during gelatinization of starch.