• Title/Summary/Keyword: microwave power

Search Result 786, Processing Time 0.031 seconds

A Study of a period boundary by microwave generator (주기경계를 갖는 마이크로파 발생장치 연구)

  • Kim, Won-Sop;Kim, Jeong-Man
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2007.11a
    • /
    • pp.481-481
    • /
    • 2007
  • The characteristics of slow wave structure employed for backward wave oscillator expected to be a high power microwave source are studied analytically. The slow wave structure is a sinusodially corrugated wall waveguide. The waveguide is designed and transmitted characteristics for microwave are measured in the air. There exist literatures on high efficiency of enhansed radiation from backward wave oscillators involving plasmastudied experimentally another results.

  • PDF

Optimization of microwave-assisted extraction process for blue honeysuckle (Lonicera coerulea L.) using response surface methodology (반응표면분석법을 이용한 댕댕이 기능성성분의 마이크로웨이브추출조건 최적화)

  • Park, Daehee;Lee, Jae-Jun;Park, Jongjin;Park, Sanghwan;Lee, Wonyoung
    • Food Science and Preservation
    • /
    • v.24 no.5
    • /
    • pp.623-630
    • /
    • 2017
  • Functional compounds including flavonoids, anthocyanins, polyphneols and antioxidants were extracted from blue honeysuckle (Lonicera caerulea L.) using highly efficient microwave-assisted extraction. And extraction process was modeled and optimized according to response surface methodology (RSM). The independent variables ($X_n$) were ethanol concentration ($X_1$: 0, 25, 50, 75, 100%), irradiation time ($X_2$: 1, 3, 5, 7, 9 min), and microwave power ($X_3$: 60, 120, 180, 240, 300 W). Dependent variables ($Y_n$) were total flavonoid contents ($Y_1$), total anthocyanin contents ($Y_2$), total polyphenol contents ($Y_3$) and antioxidant activity ($Y_4$). Four-dimensional response surface plots were generated based on the fitted second-order polynomial models to get optimal conditions. Estimated optimal conditions for 4 responses were ethanol concentration of 54-72%, irradiation time of 7.1-7.6 min, and microwave power of 243-251 W. Ridge analysis predicted the maximal responses of total flavonoid content, total anthocyanin content, total polyphenol content and antioxidant activity were 38.00 mg RE/g, 6.80 mg CGE/g, 14.90 mg GAE/g, 89.10%, respectively. Verification experiment was carried out at predicted optimal conditions and experimental values for total flavonoid content, total anthocyanin content, total polyphenol content and antioxidant activity were 38.10 mg RE/g, 6.72 mg CGE/g, 14.91 mg GAE/g and 89.13%, respectively. No significant difference was observed between predicted and experimental values, indicating good fitness of fitted model and successful application of RSM.

Design and Fabrication of Rectenna for Microwave Wireless Power Transmission (마이크로파 무선전력전송을 위한 렉테나 설계와 구현)

  • Park, Jeong-Heum
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.20 no.6
    • /
    • pp.43-48
    • /
    • 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.

Breakdown and Destruction Characteristics of the CMOS IC by High Power Microwave (고출력 과도 전자파에 의한 CMOS IC의 오동작 및 파괴 특성)

  • Hong, Joo-Il;Hwang, Sun-Mook;Huh, Chang-Su
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.56 no.7
    • /
    • pp.1282-1287
    • /
    • 2007
  • We investigated the damage of the CMOS IC which manufactured three different technologies by high power microwave. The tests separated the two methods in accordance with the types of the CMOS IC located inner waveguide. The only CMOS IC which was located inner waveguide was occurred breakdown below the max electric field (23.94kV/m) without destruction but the CMOS IC which was connected IC to line organically was located inner waveguide and it was occurred breakdown and destruction below the max electric field. Also destructed CMOS IC was removed their surface and a chip condition was analyzed by SEM. The SEM analysis of the damaged devices showed onchuipwire and bondwire destruction like melting due to thermal effect. The tested results are applied to the fundamental data which interprets the combination mechanism of the semiconductors from artificial electromagnetic wave environment and are applied to the data which understand electromagnetic wave effects of electronic equipments.

The fabrication of rf termination power resistor (고주파용 Termination 파워저항의 제작)

  • Ryu, J.C.;Kim, D.J.;Kang, B.D.;Koo, B.K.;Kang, J.H.;Yu, K.M.;Ryu, K.S.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2002.07b
    • /
    • pp.553-555
    • /
    • 2002
  • We were fabricated of rf power resisotor on AlN substrates by thick film process. The characteristics of capacitance and microwave are measured by digital LCR meter and Network analyzer(HP8532D). The results are shown that capacitances are slight greater and microwave characteristics are good values.

  • PDF

Performance Comparison between Inverse Class-F and Class-F Amplifiers Based on the Waveform Analysis

  • Yang, Youn-goo;Woo, Young-Yun;Kim, Bum-man
    • Journal of electromagnetic engineering and science
    • /
    • v.2 no.1
    • /
    • pp.5-10
    • /
    • 2002
  • We have analized the inverse class-F and class-F amplifiers using their waveforms. From the analytic equations derived from the analysis, we have calculated tole efficiencies, output powers, DC power dissipations, and optimum fundamental load impedances of the inverse class-F and class-F amplifiers. We also have compared them for various operation conditions, which include the same peak current, saute DC power dissipation, same fundamental RF output power, and same fundamental load impedance with different Ron(on-resistance). These analyses have clearly shown the performance limitations, advantages, and guide to the optimized design of the inverse class-F amplifiers.

A Study on the Microwave Reflection of Plasma in a Magnetic Field (방전프라즈마내 자계에 의한 마이크로파 반사특성)

  • 김봉열;김정기
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.6 no.1
    • /
    • pp.12-18
    • /
    • 1969
  • The characteristics of microwave reflection in the media of cold gaseous plasma is analysed to various external magnetic flux density. The DC discharge plasma is generated in the rectangular waveguide which contains two electrodes and helium gas at the pressure of 10-2mm Hg. The reflected and transmitted power of microwave is measured when the electric field is parallel to, and perpendicular to the external magnetic field. It shows that the reflected power is increased as the magnetic flux density is increased in the parallel case, but the maximum value of the reflected power is occured at the cyclotron resonance (3120 Gauss) in the perpendicular case.

  • PDF

Drying Characteristics of Plating Sludge by Microwave (마이크로파 가열에 의한 도금슬러지 건조특성)

  • 문경환;손종렬;김덕찬
    • Journal of environmental and Sanitary engineering
    • /
    • v.13 no.1
    • /
    • pp.9-15
    • /
    • 1998
  • Microwave heating and drying processes have been well established in various industrial applications. Feasibilities of successful application of microwave drying to many material have been shown on the laboratory or pilot-plant scale. The microwave drying behavior of plating sludge are considered in this paper. The plating sludge containing 70%, 80% and 90% water exposed to microwave power at 2,450 MHz, 700W. An experimental microwave drying apparatus was designed and constructed to monitor weight loss during drying. By studying the drying characteristic curve, the moisture in sludge was almost classified into two categories : free moisture and intestinal moisture. And the critical moisture contents at which the drying rate ceases to be constant were from 10.1 to 10.5%. A simple drying model is proposed which may be used to describe drying behavior of plating sludge. The constant rate and the falling rate periods in microwave drying were addressed separately. From the eqation of constant rate period the drying rate constants decreased exponentially with increasing depth. Microwave heating compared with conventional heating offered higher heating rates from 9 to 16 times. Therefore, microwave drying process can be effective in removing moisture from plating sludge.

  • PDF

Drying characteristics of lotus root under microwave and hot-air combination drying

  • Joe, Sung Yong;So, Jun Hwi;Lee, Seung Hyun
    • Korean Journal of Agricultural Science
    • /
    • v.47 no.3
    • /
    • pp.519-532
    • /
    • 2020
  • Because lotus root has a short shelf life, the quality easily deteriorates. Thus, the harvested lotus roots are processed into a variety of products. Drying is one of the simplest food preservation methods, which can increase food stability. However, the convective drying method takes a long time and requires high energy consumption. Combination drying methods have emerged to overcome the limitations of the convective drying method. This study investigated the drying characteristics of lotus root and determined the optimal drying model of lotus root depending on the microwave and hot-air combination drying conditions. The lotus root slices (5 mm in thickness and 40 mm in diameter) were dried by different drying conditions that were combined with three microwave power levels (50, 100, and 150 W) and two hot air temperatures (50 and 60℃) at a velocity of 5 m·s-1. Eight drying models were tested to evaluate the fit to the experimental drying data, and the effective moisture diffusion (Deff) values of the lotus root slices dried by combination drying were estimated. The combination drying time of the lotus root was significantly reduced with the high air temperature and microwave power. The effective moisture diffusion (Deff) of lotus root was more affected by the air temperature than microwave power intensity. Logarithmic model was most suitable to describe the drying curve of lotus root in the microwave-hot air combination drying method.