Search

Your search keyword '"Ma, Ziji"' showing total 66 results
Start Over Author "Ma, Ziji"
66 results on '"Ma, Ziji"'

56. A new configuration of magnetic coupled power transfer using parallel line feeder

Author

Ryuhei Tanaka, Minoru Okada, Yasuaki Tatsuta, Ma Ziji, Takeshi Higashino, Yoshikazu Goto, and Yoshinori Tsuruda

Subjects
Engineering, Electrical load, business.industry, Impedance matching, Electrical engineering, Power factor, Input impedance, Hardware_GENERAL, Power module, Electronic engineering, Maximum power transfer theorem, Equivalent circuit, Wireless power transfer, business
Abstract

This paper newly proposes a configuration of magnetic coupling in wireless power transform using parallel line power feeder. Previous researches mentioned that coil design and optimization of circuit parameters are necessary for strong magnetic coupled resonance. Then, these constraints prevent expansion of coverage area of wireless power transfer to electric portable devices, and electric vehicles. In order to make breakthrough against these limitations, this paper introduces parallel line as a feeder. The frequency of the electromagnetic wave is selected at 13.56 [MHz] in high frequency (HF) band, which is suitable for strong magnetic coupled resonance. Fundamental characteristics are evaluated by using equivalent circuits which are referred to the previous works. Theoretical analysis asserts that impedance transform is necessary in a power source and load circuits. Computer simulation evaluates a mutual inductance between primary and secondary coils, and optimum value of load resistance is clarified. Finally, input impedance and S-parameter are evaluated when power source circuit and feeder circuit are magnetic coupled resonance, these results imply that enhancement of power transfer efficiency is a further study.

Published
2013

64. Adaptive impulsive noise suppression for ISDB-T receivers

Author

Ma, Ziji, Miyamoto, Ryusuke, and Okada, Minoru

Abstract

Orthogonal Frequency Division Multiplexing (OFDM) is the primary modulation technique used for Integrated Services for Digital Broadcasting for Terrestrial (ISDB-T). However, the performance of OFDM systems is often affected by impulsive noise significantly. In this paper, we propose an adaptive scheme of impulsive noise suppression for ISDB-T receivers. We detect the position and burst duration of impulsive noise by using guard band in frequency-domain, and use an adaptive window function to suppress the impulsive interference in time-domain. Simulation results confirm the validity of the proposed scheme for ISDB-T receivers in AWGN channel and Rayleigh fading channel.

Published
2011
Full Text
View/download PDF

66. Cl-Initiated oxidation of methacrolein under NO x -free conditions studied by VUV photoionization mass spectrometry.

Author

Lin X, Hu R, Ma Z, Yue H, Wen Z, Zhang C, Fittschen C, Zhang W, and Tang X

Abstract

The Cl-initiated oxidation of methacrolein (MACR, C 4 H 6 O) under NO x -free conditions has been investigated in a fast flow tube by using a home-made vacuum ultraviolet (VUV) photoionization mass spectrometer complemented by high-level theoretical calculations. The key species such as intermediates and radicals together with products involved in the oxidation are observed online and confirmed in photoionization mass spectra. The reaction potential energy surfaces of the transient C 4 H 5 O and C 4 H 6 OCl radicals, formed from the hydrogen-abstraction reaction and the addition reaction of MACR with Cl atoms, with oxygen have been theoretically calculated to illuminate the formation of the peroxy radicals of C 4 H 5 OO 2 and C 4 H 6 OClO 2 . The photoionization processes of these peroxy radicals, whose cations are not stable, and their individual self-reactions as well as bimolecular reactions with HO 2 radical are studied and discussed. In addition, kinetic experiments are also performed to get the time evolution of specific products and compared with theoretical models, providing a detailed insight into the reaction mechanism of the Cl-initiated oxidation of MACR.

Published
2022
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results