• Food Science of Animal Resources
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• v.29 no.1
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• pp.82-90
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• 2009

This study was carried out to evaluate the effects of microwave power level on cooking properties of ground pork patties (fat level: 20%). Each patty was cooked from a thawed state to $76.7^{\circ}C$ (center temperature) in a microwave oven with power levels of 40% (360 W), 60% (540 W), 80% (720 W), and 100% (full power, 900 W), respectively. Cooking rate increased with power level, and the non-uniformity also increased with time during cooking. Overheating at the edge of the patties was observed for all power levels, and maximum temperature differences in between the edge position and center position were found in patties cooked at the 900 W power level. Compositional properties, total cooking loss, and drip loss were not affected by power level, although moisture content was lower at the edge than at the center position. As the power level increased, the reduction in patty diameter of cooked patties increased while the reduction in patty thickness decreased. Pork patties cooked at lower power levels (360 W and 540 W) had higher shear force values than those cooked at higher power levels (720 W and 900 W). Few changes were observed in instrumental color values.

• Korean journal of food and cookery science
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• v.10 no.4
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• pp.357-362
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• 1994

Beef loaves(5${\times}5{\times}$5cm) were cooked by conventional moist-heat and by various levels of microwaves. The mean internal temperature of the meats cooked by low power microwaves for 5~15 min were not significantly different from the conventionally boiled meats for 30 min. When cooking was made by microwaves at low level for 5~10 min, or at high level for 2 min and additional heating at low power level for 5min, the percent cooking loss were comparable with the samples cooked conventionally for 20~40 min. General proteolytic activity determined with azocoll indicated that enzyme activity decreased as internal temperature increased(r=-0.5779, p<0.05), and maximum activity occured at meats conventionally moist-heated for 10 min and by low power microwave for 5 min. Sensory scores for tenderness were high at conventional moist-heat for 30 min, for 20 min, microwave cooked at thatwing power for 10 min and at low power level for 10 min, in descending order. There were no significant differences in the thiamin content of meats after various treatments.

• Korean journal of food and cookery science
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• v.11 no.2
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• pp.98-103
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• 1995

The effect of blanching time, blanching water and power settings of microwave oven on the minerals retention in spinach and broccoli were investigated. The vegetables were blanched for 60, 120 and 180 sec, with water 0ml, 50ml and 100ml every 100 g of raw material at two different power settings (700w, 400w). The retention of minerals(Ca,K,Mg,Cu,Fe,Na,p) in spinach and broccoli were higher at the 400w power than 700w power level, regardless of blanching time. At the high power, the retention of minerals in spinach and broccoli were reduced remarkably as the blanching time increased. The reason for this is that the increasing power level results in greater water coming ou from the vegetable. Also, minerals in vegetable as coming out with this water loss in proportion to the blanching time.

• Korean journal of food and cookery science
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• v.14 no.1
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• pp.44-49
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• 1998

The microwave cooking of rice was studied for the purpose of establishing optimum conditions of power level and heating time. Optimum volume of adding water was 290 ml per 173 g rice. The longer the rice was soaked, the better the cooked rice. However, we chose one hour as soaking time so that we might observe well the effects of power levels. The mode of microwave cooking consisted of 5 steps of power level; step 1: temperature ascendance, step 2: water absorption 1, step 3: water absorption 2, step 4: heat penetration, step 5: gelatinization completion. The quality of cooked rice was evaluated subjectively. As a result of the study, 3 optimum conditions were chosen as follows. 1) (7) 5:00-(1) 5:00-(2) 5:00-(2) 6:00-(7) 4:00, 2) (8) 4:25-(1) 5:00-(2) 5:00-(2) 5:00-(6) 4:00,3) (9) 3:40-(1) 5:00-(2) 5:00-(3) 6:00-(7) 2:00

• Journal of the Korean Chemical Society
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• v.55 no.6
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• pp.983-987
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• 2011

Surveys on the process of extracting acid from dried rinds of Garcinia oblongifolia Champ. ex Benth (G. oblongifolia) using microwave in terms of time, machine power and solid/liquid rate, have resulted in such findings as: the best time allocation for extracting is 25 minutes; machine power works best at level 2 (microwave power is 400 W); suitable rate of solid/liquid is 0.071 (approximately 150 mL solvent per 10 g of sample). The total amounts acid and (-)-hydroxycitric acid extracted from 100 g dried rinds of G. oblongifolia are 18.592 g and 10.137g respectively. This is the first finding on extraction of (-)-HCA from dried rinds of G. oblongifolia using microwave.

• 한국정보통신설비학회:학술대회논문집
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• 2005.08a
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• pp.149-153
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• 2005

The optical fiber micro-cellular system requires the high linearity that determines the quality and capacity of system. Hence, there is a need for improving the linearity in mobile communication system. In order to compensate dispersion-induced signal distortion, we fabricated the optical feedforward transmitter. The compared 3rd-IMD was enhanced by 38 dB for two-tone case and the Adjacent Channel Power Ratio was enhanced by 20 dB for W-CDMA 1 carrier and by 16 dB for W-CDMA 3 carriers. Also, the induced noise level was reduced.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.6
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• pp.872-877
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• 2017

Objective: In order to utilize fat from broiler byproducts efficiently, it is necessary to develop an appropriate rendering procedure and establish quality information for the rendered fat. A study was therefore undertaken to evaluate the influence of rendering methods on the amounts and general properties of the fat recovered from broiler skin. Methods: The yield and quality of the broiler skin fat rendered through high and lower energy microwave rendering (3.6 W/g for 10 min and 2.4 W/g for 10 min for high power microwave rendering (HPMR) and high power microwave rendering (LPMR), respectively), oven baking (OB, at $180^{\circ}C$ for 40 min), and water cooking (WC, boiling for 40 min) were compared. Results: Microwave-rendered skin exhibited the highest yields and fat recovery rates, followed by OB, and WC fats (p<0.05). HPMR fat had the highest $L^{\star}$, $a^{\star}$, and $b^{\star}$ values, whereas WC fat had the highest moisture content, acid values, and thiobarbituric acid (TBA) values (p<0.05). There was no significant difference in the acid value, peroxide value, and TBA values between HPMR and LPMR fats. Conclusion: Microwave rendering at a power level of 3.6 W/g for 10 min is suggested base on the yield and quality of chicken fat.

• Food Science of Animal Resources
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• v.36 no.4
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• pp.538-546
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• 2016

This study was carried out to evaluate the effects of fat level on the microwave cooking properties of ground pork patties with NaCl (1.5%). Ground pork patties were processed from pork hams to achieve fat levels of 10%, 15%, 20%, and 25%, respectively. Each patty was cooked from a thawed state to 75℃ in a microwave oven at full power (700 W). After microwave cooking, protein content, moisture content, fat retention, and shear force values in patties decreased as fat level increased from 10 to 25%. As fat level increased, cooking time decreased but total cooking loss and drip loss were increased, whereas slight differences in diameter reduction and thickness of patties were observed. In raw patties, 10% fat patties had lower L* values and higher a* values compared to patties with more fat, but these differences were reduced when patties were cooked. Patties with 10% fat showed a more pink color on the surface and interior than patties with a higher fat content but more air pockets were noted in higher-fat patties. Higher-fat patties were more tender, juicy, and oily than lower-fat patties.

• The Korean Journal of Ceramics
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• v.6 no.3
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• pp.300-303
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• 2000

The generation of the intermodulation noises in microwave isolators has been studied in relation to the characteristics of YIG ferrites designed for this application. We have investigated the influences of porosity and crystalline anisotropy related to the magnetic loss, which causes the generation of intermodulation signals. The power dependence of the intermodulation power level is stressed as the crystalline anisotropy decreases. These results are consistent with the nonlinear effects of a single normal mode before the excitation of the spin-waves. It also appears that this power level is proportional to the magnitude of dc bias magnetic field.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.6
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• pp.43-48
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• 2006

In this paper, the rectenna converting 2.45[GHz] microwave into DC power is designed and fabricated for wireless power transmission using microwave and the methode for impedance matching and tuning are proposed in order to maximize RF-DC conversion efficiency. The fabricated rectenna can be easily tuned by using a broad open stub and has the RF-DC conversion efficiency up to 59[%] when the 5[dBm] input power is applied. The 2.2[V], 1.5[mW] DC level, in the 1[m] distance between the transmitter and the receiver can be obtained and this value is avaliable in the small power digital system.