• Journal of the Korean Home Economics Association
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• v.24 no.4
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• pp.93-104
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• 1986

The purpose of this study was to see that how about the related variables influence on the use of the microwave oven and how about the use of the microwave oven influence on the time spent in meal preparation and meal management. Questionaires were give to randomly selected homaker's, in kwangju in August, 1986. Data from the 149 response were analyzed according to multiple regression. The results were as follows; 1. The variables affecting the use of the microwave oven were family income, homaker's employed hours, homakers' education level, a period of use a microwave oven, congnition of a special character in a microwave oven, family style of participation in meal preparation, frequency in use of instant food. 2. The variables of the use the microwave oven was significantly influence on the time spent in meal preparation. 3. The variables of the use the microwave oven was not significantly influence on meal management.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.2
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• pp.171-176
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• 1985

The effects of cooking methods by boiling, electric oven and microwave on the proximate composition, minerals and water-soluble vitamins of two major Korean potato varieties (Soomi and Namjac) were studied. The dry matter content was increased after the cooking by the methods of electric oven and microwave, however, the crude fiber content was highly decreased by both methods. The crude ash content was not affected by the cooking methods used. The potassium content was increased by electric oven and microwave methods, and iron content was increased by electric oven baking, however, the copper content was significantly decreased by the electric oven and microwave cooking methods. The macrominerals (phosphorus, magnesium, calcium) and microminerals (zinc, manganese, nickel, lead, cadmium) content present initially in potatoes have not been changed by the cooking methods employed in this study. Relative retention value of ascorbic acid was the lowest and the value of thiamin was the highest in the potatoes cooked by microwave. The retention values of riboflavin and folic acid obtained. after boiling were similar to those after microwave cooking, and both of these treatments were superior to the electric oven baking. The retention values of niacin and vitamin $B_6$ varied between 93 and 100% depending on the cooking methods used. Overall, with a few exceptions, the retention values of water-soluble vitamins in boiled and microwave cooked potatoes were superior to those of the electric oven baked.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.129-130
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• 2006

As the research of wireless personal area network (WPAN) is more activated, various communication systems operating on 2.4Ghz are being developed. Systems such as Bluetooth, 802.11b, Zigbee and DBO-CSS are operating on 2.4Ghz. In addition to these communication systems, microwave oven resides in 2.4Ghz, so co-existance between each of these communication systems and microwave Oven is considered important factor of system performance. The effect of microwave oven on these communication systems is so critical that these systems are recommended to avoid the impact of microwave oven by allocation of different channel. In this paper, based on the DBO-CSS operating on 2.4Ghz, we propose a new algorithm of reducing the effect of microwave oven to develop robust communication system against microwave oven.

• Korean journal of food and cookery science
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• v.7 no.1
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• pp.53-59
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• 1991

The purpose of this study is to investigate textural characteristics of egg solution coagulated with steamer and microwave oven, and egg solution diluted various concentration of it with water or milk. Textural Characteristics of the samples were evaluated by the Sensory test and Rheometer. The results obstained were as follow; 1. Rheometer measurement indicated that the thicker is concentration of egg solution, the harder is samples 2. In sensory evaluation on the various concentration of egg solution, the panels on the overall quality showed the most favorite tendency that the sample diluted with 50% of water and the one with 70% of milk in use steamer; the sample diluted with 30% of water and the one with 70% of milk in use microwave oven.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.12 s.177
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• pp.141-148
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• 2005

When one opens the door of a microwave oven during operation, microwave might leak through the clearance of the door. Present research has been motivated by the need to reduce the possible clearance by enhancing torsional stiffness of the door of the microwave oven. Static deformation of the door frame of the oven is analyzed under a door-opening force. On the basis of the topological optimization, the right flange of the door frame is shown to need reinforcing. Several types of reinforcing brackets weldable to the right flange is proposed, and their effects to the stiffness of the door frame are compared and evaluated.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.1
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• pp.48-55
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• 2001

The purpose of this study was to evaluate the analytical accuracy and precision of microwave oven digestion/atomi absorption spectrophotometry (AAS) for analyzing airborne chromium collected on mixed cellulose ester membrane (M filter from the work environment, and to compare the accuracy and the precision with those of the National Institute for Occupational Safety and Health (NIOSH) Method #7024 hot plate digestion/AAS method. For this study, field air sample pairs were collected from a electroplating process, and spiked samples in a laboratory were prepared and using these samples. Two digestion methods were comp; and evaluated in terms of recovery rate and bias as indices of accuracy and coefficient of variation as a index of precision. The results and conclusions are as follows. In spiked samples, the accuracies (% mean recoveries) of hot plate/AAS and microwave oven/AAS method were 97.19%, 97.1%, respectively, and the precisions (pooled respectively, and the precisions (pooled coefficient of variance, $CV_{pooled}$) 6.93% and 3.88%, respectively. The biases of hot plate ani microwave oven methods were 4.56 - 14.7% and 2.22 - 7.42% respectively. There was no statistically significant difference between hot plate and microwave oven methods recovery rates of spiked samples (p>0,05). Also, no statistically significant difference was shown among the concentrations of air samples determined by two method (p>0.05). In conclusion, microwave oven/AAS method h excellent accuracy and precision, and advantages such as time-saving and simple procedure in comparison with the classical NIOSH method. Therefore, this method can be use widely to analyze airborne chromium collected on MCE filter from the work environments.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.3
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• pp.180-187
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• 2004

A conventional power supply of a microwave oven has a 60Hz transformer and high voltage capacitor(HVC). Though it is very simple and has low cost, it has several problems such as large size, heavy weight and low efficiency To improve these problems, various high frequency inverter type power supply have been investigated and developed in recent years. But these cost is higher than the conventional one due to additional control circuit, fast switching devces. In this paper, a novel pulse power supply for microwave oven using high frequency transformer embedded HVC(High Voltage Capacitor) is proposed for down-sizing, cost reduction and efficient improvement. To verify the effectiveness of the proposed transformer, an equivalent circuit of transformer embedded HVC is derived and it's characteristic is described. And the validity of the proposed pulse power supply embedded HVC-high frequency transformer is shown by simulations and experiments accroding to various operating conditions.

• Journal of the Korean GEO-environmental Society
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• v.12 no.5
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• pp.5-12
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• 2011

Water content is one of the significant engineering properties of soil for predicting the behavior of soil matrix. Conventional drying oven can be widely used to obtain the values by drying the soil specimens for 16 to 24 hours at $105^{\circ}C$. Although a number of experimental data has been accumulated for the conventional method of drying soil for water contents, shortcomings of the method are still hard to overcome such as long drying time for in situ use and the difficulty of taking prompt actions against emergency cases. Recently, ASTM and JGS have established microwave oven drying techniques for obtaining water contents to cope with those problems. And the reliability evaluation study has been also performed on the microwave oven drying for water contents. Feasibility study of the microwave oven drying was performed to confirm the process of the technique with Jumunjin sand, kaolinite, bentonite, weathered granite soil, and organic soil. Investigation was also conducted on the factors affecting and enhancing the reliability of the technique.

• Korean Journal of Food Science and Technology
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• v.8 no.2
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• pp.80-84
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• 1976

Two varieties, Lasoda and Sebago potatoes, were studied. Different cooking methods, conventional oven baking at $218^{\circ}C$ and microwave oven baking, have been used to compare the retention of the phenolic compounds. Peeled cortex samples of fresh and cooked potatoes were analyzed for total phenols, phenolic constituents, and moisture loss. Phenolic content was higher in fresh potatoes than in cooked potatoes. Laasoda had higher phenolic content (3. 63mg) than Sebago (1. 71mg). Potatoes with higher phenols (Lasoda) also had larger quantities of chlorogenic acid. There was a greater moisture loss in conventional oven baking potatoes than in microware oven.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.7
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• pp.1172-1177
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• 2004

This paper describes a output power control of magnetron for microwave oven. Magnetron is used extensively in household microwave oven and industrial microwave heating devices it is operated by 3000[V]～5000[V] dc high voltage. Power supply for driving magnetron is consisted of a bridge rectifier. HB(half bridge) inverter, full wave rectifier and gate drive circuit. In proposed system. we confirm that line input power can be controlled extensively and linearly to 24.56[%] by change of duty ratio of inverter through a experiment.