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 : Xiaolan Han (검색결과 5 건)
- 무료
- 기관 내 무료
- 유료
-
Sequence Pulse Modulation for Voltage Balance in a Cascaded H-Bridge Rectifier
Peng, Xu,He, Xiaoqiong,Han, Pengcheng,Lin, Xiaolan,Shu, Zeliang,Gao, Shibin The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.3
With the development of multilevel converters, cascaded single-phase H-bridge rectifiers (CHBRs) has become widely adopted in high-voltage high-power applications. In this study, sequence pulse modulation (SPM) is proposed for CHBRs. SPM is designed to balance the dc-link voltage and maintain the smooth changes of switch states. In contrast to phase disposition modulation, SPM balances the dc-link voltage even after removing the load of one submodule. The operation principle of SPM is deduced, and the unbalance degree of SPM is analyzed. All the proposed approaches are experimentally verified through a prototype of a four-module (nine-level) CHBR. Conclusions are drawn in accordance with the results of SPM and its imbalance degree analysis.
-
Flight Performance Optimization Considering Environmental Impact Under Multi-RTA Constraints
Runping Gu,Jie Yuan,Xiaolan Han,Zhiqiang Wei,Na Li 한국항공우주학회 2019 International Journal of Aeronautical and Space Sc Vol.20 No.4
To optimize the flight performance under multi-waypoint required time of arrival constraints, characteristics of the vertical flight trajectory during the en route descent process are studied. A multi-constraint segment sequence model including flight distance, flight altitude and arrival time is constructed. To ensure the rationality of constraints, the rationality detection model for multi-constraint is established. The control variables and their variation ranges are determined by analyzing the optimization process. Mathematical models of optimization objectives are studied from three aspects: fuel economy, greenhouse effect and variation of flight speed. Based on the multi-objective genetic algorithm, the optimization solution model is established. Effects of speed on the objectives are analyzed. The results indicate that the optimization model can effectively optimize the flight parameters with multiple RTA constraints. The impact of aviation on the environment can be effectively reduced. And the optimization method has a good trade-off between fuel consumption and temperature rise by changing weighted factors. Optimization results of the flight parameters are mainly affected by the maximum RTA time constraint. The proposed optimization method provides a reference for the optimization of flight parameters and trajectory under multi-RTA constraints in four dimensions.
-
Sequence Pulse Modulation for Voltage Balance in a Cascaded H-Bridge Rectifier
Xu Peng,Xiaoqiong He,Pengcheng Han,Xiaolan Lin,Zeliang Shu,Shibin Gao 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.3
With the development of multilevel converters, cascaded single-phase H-bridge rectifiers (CHBRs) has become widely adopted in high-voltage high-power applications. In this study, sequence pulse modulation (SPM) is proposed for CHBRs. SPM is designed to balance the dc-link voltage and maintain the smooth changes of switch states. In contrast to phase disposition modulation, SPM balances the dc-link voltage even after removing the load of one submodule. The operation principle of SPM is deduced, and the unbalance degree of SPM is analyzed. All the proposed approaches are experimentally verified through a prototype of a four-module (nine-level) CHBR. Conclusions are drawn in accordance with the results of SPM and its imbalance degree analysis.
-
Liu Huazhong,He Wenxuan,Xu Han,Wang Xiaolan,An Qing 한국물리학회 2023 Current Applied Physics Vol.54 No.-
We implemented DFT calculations for gas phase and DFT‒MD simulations for ambient conditions to evaluate the efficient performance of g‒Mg3N2 monolayer in 1,4‒dioxane removal from wastewater. The geometries, interaction energies, and interaction nature of the adsorbed dioxane and H2O molecules on the Mg3N2 surface were investigated. It was found that the interaction of H2O exceeds that of dioxane by twelve though, the two adsorbates follow rather a similar trend in the adsorption process. The AIM analysis was carried out to investigate the nature of bonding for adsorbed dioxane/H2O on the Mg3N2 surface. Furthermore, DFT‒MD simulation shows that dioxane tends to adsorb on the Mg3N2 nanosheet in the presence of water molecules at ambient conditions, making the Mg3N2 potentially suitable adsorbent for dioxane adsorption in aqueous solution. This exploration presents a foundation for the capability of computational study for predicting the adsorption and remediation of organic contaminants from wastewater.
-
High-accuracy servo press system for the clinching joint process
Chen Liu,Sheng-Dun Zhao,Xiaolan Han,Tong Guo 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.2
This paper focuses on the quality improvements on clinching joints using a servo press with a Radial basis function neural network and a sliding mode (RBFS) control strategy. Bottom thickness, which is affected by the press punch position, is usually used to monitor clinching joint quality. Traditional clinching presses are driven by pneumatic pistons or motors that provide feedback on punch force or motor position. However, this feedback is indirectly related to the joint bottom thickness. Clinching workers who set the control parameters on these presses depend on tests and statistics. Thus, this paper presents a servo press system that utilizes punch position feedback to directly control the joint bottom thickness. Transmission errors are considered for the movement accuracy of the servo press. A mathematical model of the servo press is established for analyzing. An algorithm, which combines RBF neural network and sliding mode, is proposed and applied for press position tracking. This algorithm adopts an RBF neural network to approximate the nominal model of the press system. The update law of the algorithm is based on the Lyapunov function used to prove the stability of a closed-loop system. The sliding mode controller compensates for the neural network error and disturbance. Finally, experiments are executed on the servo press with an RBFS controller. To evaluate the performance of the proposed method, a fuzzy PID controller is also applied to the press for comparison. The results indicate that the servo clinching press system with RBFS efficiently and accurately control the clinching jointing process.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
