Search

Your search keyword '"Qian, Jihong"' showing total 2 results
Start Over Author "Qian, Jihong" Database Supplemental Index
2 results on '"Qian, Jihong"'

1. Three-level boost inverter with capacitor voltage self-balancing and high conversion efficiency for low DC voltage systems

Author

Hu, Bihua, Tang, Zhaohong, Zhang, Zhi, Linghu, Jinqing, Qian, Jihong, Qin, Xiangyun, Meng, Bumin, and Han, Rong

Abstract

Currently, Z-source networks are widely employed to extend the output-voltage range of inverters operating at a low voltage DC source. However, these inverters are troubled by low power-conversion efficiency and an obvious current distortion due to the copper losses and core losses of the inductors. In addition, they have limited voltage levels. In this paper, a novel boost network composed of two power switches, two capacitors, and two diodes is proposed to overcome these shortcomings. Meanwhile, a corresponding modulation strategy is also set forth to achieve capacitor voltage self-balancing and to regulate the output AC voltage. Moreover, by adding more switched-capacitor cells, the range of the output voltage can be further improved, and the max DC/AC-voltage conversion ratio of the inverter withncells is √3(n+ 1)/3. At last, an inverter prototype with a 1 kW power rating is built, and the obtained results demonstrate that this inverter possesses the following superiorities: a wider range of output voltage, automatic balancing of the capacitor voltage, less current distortion, and high-efficiency power conversion.

Published
2023
Full Text
View/download PDF

2. Integrated measures for prevention of invasive Candida infections in preterm infants in a Chinese neonatal intensive care unit.

Author

Chen, Jiahui, Yu, Xiaodan, Zhou, Yijun, Zhang, Yongjun, Zhu, Jianxing, Xie, Lijuan, Qian, Jihong, Yang, Qingnan, Xia, Hongping, Zhu, Tianwen, Zhang, Yonghong, Chen, Yan, Zhao, Dongying, and He, Zhenjuan

Abstract

Background The increasing incidence of invasive Candida infections (ICIs) in preterm infants in the neonatal intensive care unit (NICU) of Xinhua Hospital aroused our concern. We undertook a retrospective study to evaluate the efficacy of different preventive measures for ICI in preterm infants. Methods Preterm infants with gestational age (GA) <33 weeks admitted between 2010 and 2013 were divided into 3 groups according to the preventive measures applied in different periods: the control group (CG), fluconazole group (FG), and integrated measures group (IMG). We analyzed the incidence of ICI and distribution of fungal pathogens in these 3 groups, and also evaluated the efficiency of various measures in preventing ICIs in preterm infants. Results The study sample comprised 261 preterm infants born at <33 weeks GA, including 94 in the CG, 99 in the FG, and 68 in the IMG. The differences among the groups were not significant at baseline. ICI developed in 41 of the 261 infants (15.7%). The incidence of ICI varied significantly among the groups: 22.3% in the CG (21/94), 18.2% in the FG (18/99), and only 2.9% in the IMG (2/68) ( P = .003). ICI was less frequent in the IMG compared with the CG ( P <.001) and the FG ( P = .003). Conclusions The integrated measures approach is meaningful for the prevention of ICIs in preterm infants in NICUs with many patients but inadequate medical resources in some developing countries. [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results