• 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 Ceramic Society
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• v.32 no.2
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• pp.227-233
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• 1995

By using homestyle microwave oven, Al-Al2O3 powder mixture could be oxidized and sintered into Al2O3 body. The differences in powder characteristics among the differently processed raw materials affect the oxidation and sintering behaviours, and these effects were more pronounced in case of microwave oven than of conventional furnace. Al-Al2O3 powder mixture was oxidized and sintered within 2hrs, which could save both processing time and energy.

• Journal of Ginseng Research
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• v.17 no.1
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• pp.35-38
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• 1993

A new and rapid method for the hydrolysis of ginsenosides to panaxadiol or panaxatriol was developed. It is based on the microwave oven reaction, which is high temperature and high-pressure reaction. The optimal hydrolysis time using 5% $H_2SO_4$ solution was found at 10 min PTFE reaction vessel in microwave oven, which is more than 30 times faster than the conventional hydrolysis method.

• Journal of the Korean Geotechnical Society
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• v.29 no.10
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• pp.29-37
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• 2013

Organic soils are widely distributed at Youngdong areas in Kangwon prefecture and Jeonbuk area. Such organic soils usually consist of undecomposed fiber materials. It is difficult to exactly measure the water content of such organic soils because some organic materials may decompose at $110^{\circ}C$ in drying oven. In this study, both drying oven and microwave oven methods are used to measure the water content of organic soils. Three different levels of oven temperature, $60^{\circ}C$, $80^{\circ}C$, and the standard temperature of $110^{\circ}C$, were used to measure the water content of organic soils in the 1st, 2nd, and 3rd day. The water content by microwave oven was measured for two different sample masses (30, 60 g) with five different measuring times (3, 6, 9, 12, 15 min.). As the temperature increased, the water content of organic soils increased due to the decomposition of organic materials in soils. The water content of some soils increased up to 2 times as the temperature was increased from $60^{\circ}C$ to $110^{\circ}C$. However, the water content was not changed after the 1st day, regardless of drying oven temperature and soil types. The water content by microwave oven became constant after 12 min. for the 30 g sample and 15 min. for the 60 g sample used. The measured water content by microwave oven was similar to that measured by drying oven at $60^{\circ}C$.

• Korean journal of food and cookery science
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• v.24 no.3
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• pp.382-391
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• 2008

Yukwa samples, made with additions of 0, 10, 20, and 30% Rubus coreanus Miquel extract, were puffed by different puffing methods(convection oven, microwave oven, and fryer) and were then examined for quality characteristics such as moisture content, expansion rate, color, hardness, and sensory qualities, in order to determine the optimal ratio of Rubus coreanus Miquel extract in the formulation and the optimal expansion of Yukwa. The moisture contents of Yukwa base increased as the level of Rubus coreanus Miquel extract increased. And the Yukwa puffed by convection had higher moisture than the samples puffed by microwave oven or frying, with the exception of the sample containing 20% Rubus coreanus Miquel extract. When comparing the expansion rates of samples, no significant differences were found between the control and extract-containing samples puffed by convection, microwave, and frying methods, respectively. However, the sample puffed by frying had the highest expansion rate, whereas the convection-, microwave-puffed samples showed no significant differences. In the convection-, microwave-, and fryer-puffed samples, lightness and yellowness decreased, but redness increased, as the level of Rubus coreanus Miquel extract increased. And the sample puffed by microwave oven had greater lightness as compared to the samples puffed by convection and frying. In terms of hardness, no significant differences were found the control and extract-containing samples puffed by convection and microwave methods. However, hardness was maximal in the sample puffed by convection and lowest in the sample puffed by frying, in which it increased according to the addition of Rubus coreanus Miquel extract. In the consumer acceptance evaluations and characteristics intensity rating tests, the samples puffed using convection and microwave methods showed higher scores for the majority of evaluated characteristics as compared to the samples puffed by frying. And the samples containing Rubus coreanus Miquel extract obtained fairly good scores. In conclusion, the results indicate that additions of 10$\sim$20% Rubus coreanus Miquel extract are optimal for Yukwa that is puffed by convection and microwave methods, as this range provides good physiological properties and reasonably high overall consumer acceptability.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.11 s.254
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• pp.1479-1485
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• 2006

To minimize the leakage of microwave which can occur when one pulls the door of a microwave oven during its operation, shape optimization of the door frame is presented. A numerical optimization is implemented to minimize the dynamic twisting deformation of the door frame. Shape design variables are defined, which represent the dimension of the bead in the flange. Two optimal design problems are established to minimize the maximum twisting deformation from harmonic response analysis. The problems are solved, their results being compared and evaluated.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.7
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• pp.744-749
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• 2005

This paper describes the performance improvement of power control system of magnetron (MGT) for microwave oven. The MGT is used extensively in household microwave oven and industrial microwave heating devices, and is operated by 3.0[kV] $\∼$5.0[kV] dc high voltage. The proposed power supply is consisted of a bridge rectifier, step-up converter(SUC) and its controller, half bridge inverter(HBI) and its controller, and full wave double voltage rectifier(DVR). In the proposed system, a good power factor can be obtained by the SUC' switching method that the inductor current waveforms follows that of the rectified voltage, and a line input power can be controlled to a range of 17.5[$\%$] by duty ratio (DR) adjustment of the HBI.

• Journal of Power System Engineering
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• v.13 no.3
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• pp.53-58
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• 2009

The importance of cost reduction has grown bigger to ensure the competetive power of products in the electric home appliances industry. Thus, it is necessary to assess the reliability due to drop-impact happenning in process of distribution of microwave ovens with the panel and cavity of thinner thickness for cost reduction. In the present study, the drop/impact simulation using the explicit code LS-DYNA3D has been carried out for improving the impact resistance of a microwave oven. This CAE-based design approach can be successfully applied to enhance the deteriorated dynamic behavior under the impact conditions of dropping height 70cm according to ISTA procedure 2A.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.8 s.185
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• pp.145-153
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• 2006

To minimize the possible leakage of microwave when one opens the door of a microwave oven during its operation, a structural design of the reinforcing brackets for the door frame is presented. Twisting deformation of the door frame resulting from a dynamic pulling force is analyzed by harmonic and transient response analyses. Several types of the reinforcing brackets weldable to the right flange of the door frame is taken into consideration, and their effects to the twisting deformation of the door frame are compared and evaluated. As a conclusion, a thick step-shaped bracket, which is welded to whole length of the right flange, is favorable.

• Archives of Pharmacal Research
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• v.17 no.5
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• pp.389-391
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• 1994