• Journal of the Korean Wood Science and Technology
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• v.19 no.4
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• pp.18-26
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• 1991

This study was carried out to examine not only the effect and the process of activation of aluminum sulfate for the manufacture of PB and MDF, but also application of the activation treatment to PB and MOF made with MDI adhesive. The results were as follows: 1. For the manufacture of PB, activating effect did not take place Because the low moisture content of 30% in the process of activation treatment made probably insufficient activation. It needs to examine higher moisture content for the uniform and enough activation same as that of MOF. 2. In the case of MOF, Activating effect was excellent, it showed not only better results of MOR 48%, MOE 29%, IB 60% than those of the control but also better dimensional stability. 3. Application of alum activation to the PB and MDF made with MDI adhesive yielded no effects. Maybe it was the reson that the curing mechanism of MDI is different. 4. Modifing the wood surface was the oxidation and wettability was not the variable limiting glueline performance. It is necessary to make a more study about activating reaction.

• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.349-356
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• 2009

Logs with average diameters of 20~30 cm were dried with microwave to investigate microwave drying characteristic of log and determine the optimal drying conditions. Microwave dryer with output of 20 kW was controlled with respect to the temperature of log during drying. Japanese red pine logs with average diameter of 281.9 mm were dried safely by microwave to below moisture content of 20% within 48 hours. Chinese toon logs showed serious surface checks during microwave drying. Higher drying rates were found with higher initial moisture content.

• Journal of Technologic Dentistry
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• v.33 no.1
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• pp.15-23
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• 2011

Purpose: Thy yttria tetragonal zirconia polycrystalline(Y-TZP) is a good structural ceramic for dental restoration. But it have a problem that delamination of veneering ceramic from the Y-TZP core materials. The problem generally occur at the interface, thus this study was conducted to evaluate the interface of Y-TZP using scanning electron microscopy(SEM). Methods: To investigate this aspect, high-resolution SEM observations were made of polished and etched (HF content gel) cross-sections of the interface area. Dry and moist veneering porcelain powders were built up on the zirconia base. Results: The extent of this surface faceting is dependent upon the moisture content of the porcelain powder and the firing temperature. More moisture and higher final heating temperature accelerates the observed faceting of the Y-TZP grains at the interface to the veneering ceramic. Conclusion: These changes of the Y-TZP grains indicate that destabilization of the tetragonal phase of zirconia occurs at the interface during veneering with ceramic. It may result in a reduction of the stability of the zirconia and interface.

• Culinary science and hospitality research
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• v.14 no.1
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• pp.161-169
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• 2008

This study was performed to find out the quality characteristics of rice noodles by addition of red ginseng(0, 2, 6, 10%). The quality characteristics of the sample were estimated in terms of general composition, growth of microorganism and sensory evaluation. The results from this study were as follows. The protein, lipid and ash contents did not show significant difference in any of the groups. In dry rice noodles, moisture content significantly decreased in red ginseng groups but, in half-cooked rice noodles, moisture content significantly increased in 6 % and 10% red ginseng added groups(p<0.05). The microbial count showed less growth in red ginseng added groups after 3 months(p<0.05). According to sensory evaluation, surface color proved very good in the 10% red ginseng added group among the training panel while very good in the 2% red ginseng added group among consumers. Flavor was good in red ginseng added groups(p<0.05). Taste was very good in the 3% red ginseng added group. Appearance and overall quality were highest in the 2% and 6% red ginseng added groups(p<0.05). Therefore, rice noodles containing 2% or 6% red ginseng were most preferable and safe during 5 months and 6 days in dry and half-cooked noodles respectively.

• Journal of the Korean Wood Science and Technology
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• v.22 no.2
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• pp.61-70
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• 1994

This study was executed to find the applicability of press drying of tree disk by investigating the shrinkage and drying defect and to form appropriate model by comparing the actual moisture content(MC) and internal temperature in respect of drying time with calculated values based computer simulation to which was applied finite difference method. In press drying disk, heating period, constant drying rate period maintained plateau temperature at 100$^{\circ}C$ and falling drying rate period were significantly distinguished. Actual MC and internal temperature were analogous to those calculated at comparing points. Heat transfer model formed by Fourier's law using specific heat of moist wood and conduction coefficient considering fractional volume of each element of wood cell wall, bound water, free water and air showed applicability as basic data to developing heat expansion, shrinkage and drying stress during press drying. Also mass transfer model formed by Fick's diffusion law using water vapor diffusion coefficient showed applicability. Longitudinal shrinkage was developed by pressure of hot press and tangential shrinkage was restrained by hygrothermal recovery. The heart check, surface check and ring failure were occurred differently in species, but V-shaped crack didn't develop.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.3
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• pp.19-25
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• 1999

Effects of the process variable in Condebelt press drying including drying temperature, pressure , drying time, and moisture content of the sheets on the paper properties were examined. The experiment was performed with a static rig and Korean OCC was used as raw material. Significant improvement in sheet density, compression strength, tensile strength, surface smoothness ,etc. was obtained when condebelt drying was applied. Control of pressure and inlet dryness was found to be two most critical variables in improving sheet properties.

• Journal of the Korean Society of Food Culture
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• v.11 no.1
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• pp.1-5
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• 1996

Chemical composition and microscopic observation of white powder developed in the surface of dried persimmon which produced in several region in Korea were studied. Sugar content in flesh of dried persimmon was $56{\sim}59%$ and composed of glucose and fructose. White powder developed in the surface of dried persimmon was composed of sugar 84.6%, moisture 12.5% and insoluble matter 2.7%, respectively. The major sugar of white powder was glucose with 83.3% and fructose was 16.7%. With scanning electron microscopic obsevation, white powder was seen the shape like a plate, flower, needle and horn, and it was similiar to the shape of recrystalized glucose after hydration. White powder in surface of dried persimmon was seemed that glucose and fructose in flesh were migrated with moisture to drying surface during drying process and glucose was crystalized in the surface of dried persimmon.

• The Korean Journal of Food And Nutrition
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• v.27 no.2
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• pp.256-266
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• 2014

The purpose of this study was to determine the optimal mixing conditions of soybean oil and bread crumbs mixture for pork patty. The experiment was designed according to the central composite design of response surface methodology. There were ten experimental points, including two replicates for soybean oil and bread crumbs. The physicochemical and mechanical analyses of each sample, including pH, cooking loss, thickness increase, moisture content, lightness, hardness, adhesiveness, springiness, chewiness, and gumminess showed significant differences (p<0.05). The results of sensory evaluation showed significant differences in tenderness, juiciness, and overall quality (p<0.05). The optimum formulation calculated by numerical and graphical method was 13.61 g of soybean oil and 6.35 g of bread crumbs. The results obtained in this study will be useful to the meat industry, which tends to decrease the saturated fatty acid content with a concomitant enrichment in the unsaturated fatty acids content.

• Korean journal of food and cookery science
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• v.28 no.2
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• pp.195-206
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• 2012

The purpose of this study was to determined the optimal mixing condition of two different amounts of tomato powder (A), and starch (B) for the preparation of sausage prepared with tomato powder was determined. The content of lycopene was 3 mg/g. The experiment was designed according to the central composite design of response surface, which showed 10 experimental points including 2 replicates for tomato powder and starch. The physiochemical, mechanical, antioxidant activity and sensory characteristics of samples were measured. The results of the physiochemical, mechanical and antioxidant activity analysis of each sample, including pH, moisture content, color L, color a, color b, hardness, chewiness and cohesiveness, total phenolic content and DPPH free radical scavenging activity showed significant differences. The sensory measurements were significantly different in color, flavor, chewiness, overall quality. The optimum formulation, which was calculated using the numerical and graphical method, was determined to be 4.26 g tomato powder and 7.51 g starch.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.3
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• pp.234-238
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• 1990

The effects of salt concentration immersion time in a salt solution prior to air dehydration and heating of air temperature during dehydration upon the browning reaction and pyruvic acid content of air dried garlics to a 6.5% moisture content(wet basis) were analyzed by a response surface methodology(RSM), Those values were also predicted by using a second degree polynomial regression model. Heating of air temperature was the most significant factor affecting the both browning reaction and pyruvic acid content. Salt concentration had more influence to browning reaction than immersion time whereas immersion time was more impor-tant factor than salt concentration on a retention of pyruvic acid sugested different processing conditions. While the processing conditions to minimize the browning reaction(O.D=0.009) were 0.3% of salt solution 9 min of immersion time and 5$0^{\circ}C$ of air temperature compared to control(O.D=0.022) of air dehydration at 5$0^{\circ}C$ Pyruvic acid contents were maximized(174 $\mu$mole/g garlic solid) at the 0.1% of salt solution 3 min of immersion time and 5$0^{\circ}C$ of air temperature compared to control(147 $\mu$mole/g garlic solid) of air dehydration at 5$0^{\circ}C$