http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Kangping Wang (검색결과 5 건)
- 무료
- 기관 내 무료
- 유료
-
Evaluation of Frequency-Dependent On-Resistance of GaN Devices at High Frequency
Kangping Wang,Bingyang Li,Zhiyuan Qi,Laili Wang,Xu Yang,Aici Qiu 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5
The switching frequency of GaN-based power converters has been pushed to several MHz and even higher. At such high frequencies, this paper finds that the onresistance of GaN devices may be much higher than their DC values, especially for the devices with low on-resistance. The frequency-dependent characteristics of on-resistance are studied through electrical and thermal experiments for the first time in this paper. A simplified finite-element-simulation model is proposed to illustrate the mechanism of the frequency-dependent characteristics. The results show that the frequency-dependent characteristics of the on-resistance are closely related to the current distribution inside the GaN device and affected by the layout. In addition, two same GaNbased 10MHz DC-DC converters were designed to operate under the same conditions, and the only difference comes from the layout of GaN devices. The experimental results show that the efficiency of the converter with optimized layout is improved by 2% compared to that with conventional layout.
-
Autophagy of bovine mammary epithelial cell induced by intracellular Staphylococcus aureus
Na Geng,Kangping Liu,Jianwei Lu,Yuliang Xu,Xiaozhou Wang,Run Wang,Jianzhu Liu,Yongxia Liu,Bo Han 한국미생물학회 2020 The journal of microbiology Vol.58 No.4
Bovine mastitis is a common disease in the dairy industry that causes great economic losses. As the primary pathogen of contagious mastitis, Staphylococcus aureus (S. aureus) can invade bovine mammary epithelial cells, thus evading immune defenses and resulting in persistent infection. Recently, autophagy has been considered an important mechanism for host cells to clear intracellular pathogens. In the current study, autophagy caused by S. aureus was detected, and the correlation between autophagy and intracellular S. aureus survival was assessed. First, a model of intracellular S. aureus infection was established. Then, the autophagy of MAC-T cells was evaluated by confocal microscopy and western blot. Moreover, the activation of the PI3K-Akt-mTOR and ERK1/2 signaling pathways was determined by western blot. Finally, the relationship between intracellular bacteria and autophagy was analyzed by using autophagy regulators (3-methyladenine [3-MA], rapamycin [Rapa] and chloroquine [CQ]). The results showed that S. aureus caused obvious induction of autophagosome formation, transformation of LC3I/II, and degradation of p62/SQSTM1 in MAC-T cells; furthermore, the PI3K-Akt-mTOR and ERK1/2 signaling pathways were activated. The number of intracellular S. aureus increased significantly with autophagy activation by rapamycin, whereas the number decreased when the autophagy flux was inhibited by chloroquine. Therefore, this study indicated that intracellular S. aureus can induce autophagy and utilize it to survive in bovine mammary epithelial cells.
-
Gui-Xin Wang,Kangping Yan,Rui Liu,Miao Chen,Hanchang Kang,Xiuli Li 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.8
A novel route was designed to synthesize LiFePO4/C composites by using the Fe1.5P byproduct, mixed lithium salts, and permeated oxygen from air via a rheological phase method. The reaction process was investigated with various techniques. When the calcining time was increased from 10 to 30 h, the gradual formation of olivine structure was observed. The growth kinetics of the crystals was analyzed. SEM and TEM results indicated the as-synthesized LiFePO4 was constituted of small spheres covered with carbon particles. The discharge capacity of the LiFePO4/C composite prepared at ~700 oC for ~25 h could reach 139.7 mAh g−1 and still remained 130.2 mAh g−1 after 15 cycles at 0.2 C rate, comparable to that of the reported LiFePO4/C composite using conventional methods. Cyclic voltammogram confirmed the LiFePO4/C composite had a high purity and good lithium ion insertion/desertion redox behavior.
-
EMI Modeling and Experiment of a GaN Based LLC Half-Bridge Converter
Mofan Tian,Yuan Hao,Kangping Wang,Yang Xuan,Lang Huang,Jingjing Sun,Xu Yang 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6
This paper focuses on the electromagnetic interference (EMI) research and analysis of the MHz switching frequency GaN MOSFET based on the LLC resonant DC-DC converter. In this paper, first, the CM coupling paths are studied to get simplified models. Then the impact of the parasitic capacitors (both the capacitors to the ground and the capacitors in the devices) on the CM current are analyzed. Finally the high frequency model is derived from the work above. Moreover this paper makes the comparison between normal Si MOSFET and GaNbased MOSFET behavior in EMI. The modeling result proves that GaN MOSFET has a worse behavior on EMI test. An experiment layout which is aimed at minimizing the irrelevant factors is designed and the experiment result proves the accuracy of the modeling.
-
Operating area analysis and design of WPT systems with MEPT control
Weipeng Gao,Yanfang Fan,Chengxuan Wang,Kangping Wang,Hongchang Li 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.4
Coupled resonant tanks are key parts of wireless power transfer (WPT) systems with magnetic resonant coupling. Researchers have proposed different resonant tank design methods to improve power transfer efficiency, increase power density, reduce magnetic flux leakage, or lower VA ratings. Practical WPT systems require a closed-loop control to cope with the variations of operation conditions, but only a few studies have considered the safe operating area (SOA) of systems under closed-loop control in resonant tanks designs. In this work, we analyze closed-loop voltage and current stress characteristics from the aspect of maximum efficiency point tracking control and derive the SOA with a given set of stress limits. Then, we propose a resonant parameter design method of allowing the system to safely operate with any specified range of coupling coefficient and output power. The current stress was minimized in the design to reduce the conductive loss. As for the verification, an experimental prototype was built according to the design method.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
