• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.4
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• pp.364-367
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• 1983

This experiment was designed to investigate the optimum conditions for the extraction of protein from the silkworm larvae by using the oven-dried and freeze-dried samples. The extractability was examined on the basis of kinds of extractants, ratio of sample to extractants, extraction time, temperature, and the effect of pH. The following results were obtained: (1) About 56% of proteins were extracted when 0.05M NaOH was used and the highest extractability was obtained at the ratio of 1 : 40 (sample: extractant). (2) The amount of nitrogen extracted was gradually increased when the extraction temperature was increased from $10^{\circ}C$ to $50^{\circ}C$ in both oven-dried and freeze-dried silkworm larvae. The highest amount of nitrogen was extracted at $50^{\circ}C$ in freeze-dried sample and at $60^{\circ}C$ in oven-dried sample. In addition, sixty min. of extraction time showed the highest extractability of nitrogen, however, not much difference in extractability was found after 10 min of extraction time. (3) More than 60% of nitrogens were extracted at pH 13.0, but less than 20% were extracted from pH 1.0 to 11.0. There was only slight difference in extractability of nitrogen between freeze-dried and oven-dried samples.

• The Transactions of the Korean Institute of Power Electronics
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• v.23 no.3
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• pp.225-230
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• 2018

This paper proposes a parametric design of an LLC resonant inverter used for a microwave oven. To improve the harmonic performance of the microwave oven, a current controller with a variable PI gain is proposed. Due to the recent strengthening of harmonics regulations, inverter control technology for microwave ovens is now required to satisfy harmonic performance. In an LLC resonant inverter, the voltage gain varies remarkably depending on the magnetron voltage, output power, and input voltage. To satisfy harmonic performance, a controller that can maintain operation in the zero-voltage switching (ZVS) region and control changes in voltage gain is required. The modified design of the LLC resonant inverter ensures ZVS operation even when the magnetron is heated. Application of the variable current controller improves harmonic control according to the instantaneous gain curve change. The validity of the proposed power control with a variable current controller is verified by experiments with a 1200 W microwave oven.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.5
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• pp.67-74
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• 2020

To predict the thermal deformation of an oven cabinet during the enamel process, we propose a simple finite element analysis method comprising two steps: heating and cooling. To this end, the basic mechanical and thermal properties such as thermal expansion of the enamel and steel plate were experimentally studied, and the mechanical properties of four different stainless steel (SUS) plates were evaluated to select the target material for the oven at high temperature conditions from 400 ℃ to 700 ℃. In the first analysis step of the enamel process, the SUS plate was heated to 850 ℃ and was then thermally expanded without considering the enamel coating. Next, assuming the perfect bonding of two materials (enamel coating and metal plate), the enamel plate was allowed to cool to room temperature till 22 ℃. From the results of comparing the experimental and analytical data, we can make a conclusion that the proposed method can be applied to evaluate the thermal deformation of enamel products. Especially, the thermal deformation of the oven can be predicted with different enamel coating conditions, such as uniform and nonuniform coating thickness.

• Food Science of Animal Resources
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• v.37 no.3
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• pp.410-417
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• 2017

The effect of dietary fiber enrichment (wheat bran) and cooking methods (oven, steam and microwave) on functional and physico-chemical properties of raw nuggets formulation as well as nutritional, color and textural properties of chicken nuggets were analyzed in this study. Among different cooking methods used for nuggets preparation, steam cooked nuggets had significantly (p<0.05) higher water holding capacity (56.65%), cooking yield (97.16%) and total dietary fiber content (4.32%) in comparison to oven and microwave cooked nuggets. The effect of cooking methods and wheat bran incorporation was also noticed on textural properties of the nuggets. Hardness, firmness and toughness values of oven and steam cooked nuggets were significantly (p<0.05) higher than microwave cooked nuggets. Among nuggets prepared by different cooking methods, cohesiveness of microwave cooked nuggets was found to be significantly (p<0.05) highest, whereas, oven cooked nuggets had significantly (p<0.05) highest gumminess and chewiness values. Steam cooked nuggets were found to be better among all nuggets due to their higher cooking yield and dietary fiber content.

• The Journal of Korean Academy of Prosthodontics
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• v.31 no.2
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• pp.191-205
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• 1993

In order to compare the strength of soldered joints relative to the various sol dering method, soldering processes were performed using Palladium based ceramo-metal alloy(Bond-on 4)and Nickel-cromium alloy(Vera Bond). The obtained data include difference in strength between presoldering and postsoldering The data also contain difference among postsoldered groups for 3 difference soldering methods(torch, infrared. Oven) The following results were obtained : 1. For postsoldering with Pd alloy, the oven-using group showed the highest strength while the difference in strength between the torch-using group and the infrared machine group was negligible. 2. For Pd alloy with the torch method, postsoldering resulted in the higher strength than presoldering. 3. There was a negligible difference in strength between presoldering and postsoldering when Ni-Cr alloy with torch method is used. 4. Through microscopic study of the fractured surfaces, the torch-using group showed more porosity than both the oven-using and the infrared machine groups. 5. In terms of fracturing patterns, the oven-using group showed adhesive failure while both the torch and the infrared machine groups showed cohesive failure and cohesive-adhesive failure.

• Korean Journal of Microbiology
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• v.11 no.2
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• pp.101-106
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• 1973

The microwave of 2450 MHz, generated by a household cooking oven, was evaluated for its applicability to melt various rehydrated media and to remove dissolved oxygen from tubed media for anaerobic culture. The effect on the sterilization of E. coli in selective media was also evaluated. The following results were obtained. 10 The microwave oven was useful in saving time for melting media and in eliminating heat and combustion gas from the laboratory, which were inevitable by-products in the conventional flame method. 2) Dissolved oxygen could be removed without boiling over by exposing the tubes of anaerobic culture medium after putting them in a wire basket in a beaker with water. 30 The count of E. coli during the melting of MacConkey and EMB agar were similar to those treated with open flame. The microwave treatment was not considered a possible mean to replace autoclaving even in these selective media.

• Journal of the Korean Wood Science and Technology
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• v.22 no.4
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• pp.37-42
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• 1994

The adsorption of water vapor and equilibrium moisture content(EMC) of the specimens for four softwood species dried by conventional- and high temperature method and equilibrated to 15% of the target EMC condition at 25$^{\circ}C$ were determined by oven drying method and with moisture meters. The amount of adsorption for high temperature dried red pine was significantly higher than that of conventional kiln dried wood, while those of eastern white pine, eastern hemlock and Norway spruce were not significantly different between drying methods. EMCs of these four species determined by oven drying method and with capacitive admittance moisture meter were not significantly different between drying methods. EMC of high temperature dried red pine determined with resistance moisture meter was significantly higher than that of conventional kiln dried wood. But EMCs of other species did not show significant difference between drying methods. EMCs of conventional and high-temperature dried wood determined with electronic moisture meters, especially in the case of the capacitive-admittance moisture meter measurement, were lower than that determined by oven drying method.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.6
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• pp.883-893
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• 2007

To optimize the preparation process for oven-roasted glutinous rice cake, an experiment was derived using a central mixing composite design to determine the optimal conditions. The addition of flour by soaking time as well as sucrose and water, were the independent variables, with the moisture content, color, sensory, and texture properties of the ovenroasted glutinous rice cakes selected as response variables. For the moisture content, color, sensory, and textural properties, we found significant effects for moisture, lightness, redness, hardness, and cohesiveness in the oven-roasted glutinous rice cakes, and water was one of the most influential factors. The optimal mixing conditions for the highest quality oven-roasted glutinous rice cake, in terms of sensory and textural properties, were 266.0 g of water, 25.4 g of sucrose, and 61.5 minutes of soaking time for the glutinous rice flour. The soaking time was in close to the median, whereas the water and sucrose values were slightly above the median.

• The Korean Journal of Food And Nutrition
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• v.22 no.2
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• pp.192-198
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• 2009

Cheongkukjang is a traditional fermented soybean food in Korea that is used in the manufacture of functional foods. This study was conducted to assess vitamin contents and sensory qualities of powdered Cheongkukjang dried by oven drying, far-infrared drying and freeze drying. Vitamins $B_1$, $B_2$, $B_6$, E, niacin and pantothenic acid were detected using all drying methods. However, vitamin D was not detected in the oven drying samples, and was most prevalent($82.47{\mu}g$/100 g) in the far-infrared drying samples. The sensory characteristics included color, off flavor, salty taste, bitter taste, sweet taste, roasted taste and after-taste. Oven drying and freeze drying samples exhibited highest and lowest color scores(5.62 and 2.0, respectively). Oven drying samples also exhibited the highest roasted taste score(4.76), although not significantly different from far-infrared drying samples(4.0, p<0.05), while the score of freeze drying samples(2.38) was significantly different from the other methods(p<0.05). It is concluded that freeze drying is most suitable.

• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.629-639
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• 2017

Tripitaka Koreana in Haein Temple, Hapcheon Province is the most historical and largest heritage in this country, however the species of their blocks have yet been unknown. A nondestructive test method is necessary to investigate their species. The oven-dry density of wood was measured by inversely using the principle of high frequency moisture meter. The oven-dry densities of more than 100 domestic species of specimens estimated by measurement method and high frequency moisture meter were compared and following conclusions were obtained. There was highly close correlation between the oven-dry density estimated by measurement method and the oven-dry density estimated by high frequency moisture meter. The densities of Tripitaka Koreana that was a global cultural heritage could be correctly estimated by using high frequency moisture meter and the equilibrium moisture content under which Tripitaka Koreana equilibrated, thus, it was expected to provide the key to species identification.