• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.9 s.240
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• pp.1282-1288
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• 2005

This research has been motivated by the need to minimize possible leakage of microwave when one opens the door during operation of the microwave oven. An explicit finite element program is used to analyze the transient response the door of the oven under door-opening condition. Operation of the micro switch which plays an important role to hun off the power is simulated on the basis of the response of the latch. Using the results of the analysis, twisting deformation of the door frame is defined and evaluated.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.5
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• pp.536-543
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• 2009

Dynamic behaviour of a package of a microwave oven under the drop-impact conditions is evaluated by the finite element analysis and tests. PAM-CRASH software is used for the finite element analysis and the tests are performed according to the ISTA(International Safe Transit Association) specification. Results of the analyses are compared with those of the tests and accuracy is shown to be favourable. Under the drop-impact condition of the original design, severe deformation occurs and an improved design is proposed to reduce it. The approach presented in this research can be successfully applied to reduce costs and time required to develop new models of the microwave oven.

• Korean journal of food and cookery science
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• v.8 no.3
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• pp.275-280
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• 1992

Sensory evaluation and Instron test were carried out to study me effect of different cooking methods on the quality of soybean jeolpyon. Cooking methods studied were rice cake steamer, steaming pot, pressure cooker and microwave oven. 1. There were no significant difference in color and flavor between samples cooked by various methods. Moistness of samples by steaming pot and rice cake steamer was similar. Tenderness of samples by rice caker and pressure cooker was better man others. 2. After 24 hours elapsed, me quality of soybean jeolpyon showed me order of by rice cake steamer, steaming pot, pressure cooker and microwave oven. 3. It showed mat soybean ieolpyon by microwave oven was harder man others through Instron test. 4. Hardness of jeolpyons were increased as storage time increased. The rate was higher by pressure cooker and microwave oven man by rice cake steamer and steaming pot.

• The Transactions of the Korean Institute of Power Electronics
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• v.22 no.5
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• pp.463-468
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• 2017

One of the most critical part for magnetron driving in microwave oven is start-up control. For this, switching frequency of resonant inverter should be carefully controlled in order to supply sufficient power to the filament of the magnetron and to prevent rectifier diode from destruction caused by the excessive voltage across them. This paper proposes a novel start-up control strategy for LLC resonant inverter for microwave oven considering the non-oscillation mode time and the magnetron voltage during the start-up process. The validity of the proposed method is verified through the experiment with 1,200W microwave oven using LLC resonant inverter.

• Applied Biological Chemistry
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• v.29 no.4
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• pp.372-374
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• 1986

Changes in moisture content and degrees of gelatinization during cooking of sweet potatoes by different cooking methods were studied. The samples were cooked by boiling, steaming, gas oven or microwave oven baking. Changes in the moisture content of sweet potato during cooking were +30.0% by boiling, +4.4% by steaming, -5.8% by gas oven baking, and -46.6% by microwave oven baking. The degrees of gelatinization of sweet potatoes were 83.8%, 75.7%, 73.0% and 67.7%, respectively.

• Food Science of Animal Resources
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• v.28 no.5
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• pp.535-542
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• 2008

The objective of this study was to determine the effects of different reheating methods on the quality characteristics of precooked ground pork patties with different combinations of salt (1, 2%) and phosphate (0, 0.3%). The cooking and reheating methods used were the electric grill and the microwave oven. The cooking method and the addition of phosphate had detectable effects on the quality characteristics of ground pork patties. The reheating rate by microwave oven was faster than by electric grill, and decreased with increases in salt and the addition of phosphate. Cooking loss and reduction in patty diameter after reheating by microwave oven were higher than by electric grill, and these values decreased with increasing of salt/phosphate levels. The pH of patties with added phosphate was significantly higher than patties without phosphate, and no significant difference in pH was observed among patties reheated by each method. The patties reheated by electric grill had higher moisture contents than those reheated by electric grill, and the addition of phosphate resulted in higher moisture contents. The hardness of patties reheated by electric grill was lower than patties reheated by microwave oven, and the addition of phosphate increased the hardness with both reheating methods.

• Journal of the Korean Society of Food Culture
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• v.21 no.4
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• pp.426-432
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• 2006

This study was conducted to investigate the changes in quality characteristics of frozen maesil according to thawing methods. The quality of maesil thawed in microwave oven was superior to those thaw in refrigerating temperature(5 $^{\circ}$) and in room temperature(25 $^{\circ}$). Drip loss of maesil thawed in microwave oven was 3.2${\pm}$0.2%. The total content of free sugars of maesil was 426.6 mg%, and 3% of them was decreased during thawing in microwave oven. The total content of organic acids was 5,297.2 mg%, and 2.5% of them was decreased during thawing in microwave oven. The total content of free amino acids was 281.4 mg%, and 2.1% of them was decreased during thawing in microwave oven. The principle ingredients of frozen maesil was stand for the lost contents of free sugar and a content loss of free organic acid and free amino acid were the fewest by thawing. Antioxidant effect for soybean oil and linoleic acid of maesil extract were expressd POV and TBA values. Antioxidative activity of fresh maesil extract was highest followed by maesil thawed in microwave oven, thawed in refreezing temperature (5$^{\circ}$)and room temperature (25$^{\circ}$)

• Journal of the Korean Ceramic Society
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• v.34 no.1
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• pp.1-6
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• 1997

In home-style microwave oven, silica-Al powder mixture was ignited among pellets and combustion wave-front propagated to produce Si+AIN+Al2O3 as resultant phases under N2 atmosphere. Without cooling pro-cedure the resultant phases of Si+AIN+Al2O3 continously absorbed microwave and were heated to be syn-thesized into sialon phases. This synthesis rate of sialon phases from silica-Al powder mixture in home-style microwave oven was higher than that in conventional furnace, and total processing time was around 1 hour, which could save energy and cost.

• Journal of Soil and Groundwater Environment
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• v.16 no.3
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• pp.28-37
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• 2011

A preliminary study for energy efficient soil heating and contaminant removal using microwave was conducted. Soils sampled from floodplain were heated with microwave oven, and soil heating property and energy efficiency were compared to those heated with electrical furnace. In addition the effects of water, soil organic matter, and contaminated diesel on soil heating with microwave were investigated. Even though the electrical power consumption of electrical furnace and microwave oven were similar, temperature of soil heated with microwave oven was significantly higher than that of soil heated with electrical furnace. The increase of soil moisture content delays the raise of soil temperature during heating it with microwave oven. However, the effects of total petroleum hydrocarbon (TPH) (<10%) in contaminated soil matrix and small amount of soil organic matter (<5%) on the increase of soil temperature by microwave were not significant. Further studies for contaminated soils with different texture using pilot scale microwave reactor are required for application of this technique in the field.

• 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.