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第43届中国控制会议

作者： Jie Wang Kaibin Yan ronghua zong Tianwei Wang Na Qin Deqing Huang School of Electrical Engineering Southwest Jiaotong University

Single-phase PWM is an important part of the traction drive system,its performance will directly affect the performance of the whole *** fault has become the mainstream of research,when the circuit device short circuit fault,the voltage and current will rise rapidly in a short time,and eventually lead to the occurrence of an open circuit ***,particular attention is given to the open circuit failure of *** paper proposed a fault diagnosis method based on an improved ResNet-50 ***,to obtain the characteristic information of the signal,the input signal of the network side is converted into grayscale images by signal reconstruction,which preserves the information contained in the signal to a large ***,in the diagnostic model,the attention mechanism is added to the original ResNet-50,and the network parameters are optimized to improve the network ***,the accuracy of the simulation experiment reaches96%,which is better than other *** result proves the validity of the method.

关键词： IGBTs Fault diagnosis ResNet-50 SE-Net

来源： cnki会议评论

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我国农药再评价品种开展概况

农药科学与管理 2017年第4期38卷 9-12,23页

作者：傅桂平林荣华李敏宗伏霖农业部农药检定所北京100125

本文对美国、欧盟、加拿大和我国农药再评价管理情况进行了简要分析和比较,介绍了我国近年来农药再评价品种开展情况,提出了我国农药再评价管理的发展趋势。

关键词：农药管理再评价发展趋势

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加强三唑磷风险管控的对策措施及建议

农药科学与管理 2017年第9期38卷 1-8,15页

作者：戴德江林荣华沈瑶沈颖王华弟宗伏霖浙江省农药检定管理所浙江杭州310020 农业部农药检定所北京100125

三唑磷在我国大量推广应用已有20多年,因其使用而导致的残留超标、水生物毒性、害虫抗药性及再猖獗等问题也逐渐暴露出来,亟待进行登记再评价,落实有效的风险管控措施。本文概述了三唑磷的基本特性和全国三唑磷登记、生产、销售情况,分... 详细信息

三唑磷在我国大量推广应用已有20多年,因其使用而导致的残留超标、水生物毒性、害虫抗药性及再猖獗等问题也逐渐暴露出来,亟待进行登记再评价,落实有效的风险管控措施。本文概述了三唑磷的基本特性和全国三唑磷登记、生产、销售情况,分析了三唑磷在使用过程中的突出问题,并结合当前三唑磷生产和出口现状,提出了进一步加强三唑磷安全风险管理的对策措施。

关键词：三唑磷再评价风险管理对策措施

Processes involved in the second-year warming of the 2015 El Nio event as derived from an intermediate ocean model

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Science China Earth Sciences 2017年第9期60卷 1601-1613页

作者： ZHANG ronghua GAO Chuan Key Laboratory of Ocean Circulation and Waves Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Laboratory for Ocean and Climate Dynamics Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 China University of Chinese Academy of Sciences Beijing 100049 China

The tropical Pacific experienced a sustained warm sea surface condition that started in 2014 and a very strong El Nio event in 2015. One striking feature of this event was the horseshoe-like pattern of positive subsurface thermal anomalies that was sustained in the western-central equatorial Pacific throughout 2014–2015. Observational data and an intermediate ocean model are used to describe the sea surface temperature(SST) evolution during 2014–2015. Emphasis is placed on the processes involved in the 2015 El Nio event and their relationships with SST anomalies, including remote effects associated with the propagation and reflection of oceanic equatorial waves(as indicated in sea level(SL) signals) at the boundaries and local effects of the positive subsurface thermal anomalies. It is demonstrated that the positive subsurface thermal anomaly pattern that was sustained throughout 2014–2015 played an important role in maintaining warm SST anomalies in the equatorial Pacific. Further analyses of the SST budget revealed the dominant processes contributing to SST anomalies during 2014–2015. These analyses provide an improved understanding of the extent to which processes associated with the 2015 El Nio event are consistent with current El Nio and Southern Oscillation theories.

关键词： 2015 El Nio event Intermediate ocean model Process analyses SST budget

Optimal maneuver strategy to improve the observability of angles-only rendezvous

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Journal of Systems Engineering and Electronics 2023年第4期34卷 1020-1032页

作者： DU ronghua LIAO Wenhe ZHANG Xiang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

This paper proposes an optimal maneuver strategy to improve the observability of angles-only rendezvous from the perspective of relative navigation.A set of dimensionless relative orbital elements(ROEs)is used to parameterize the relative motion,and the objective function of the observability of anglesonly navigation is *** analytical solution of the optimal maneuver strategy to improve the observability of anglesonly navigation is obtained by means of numerical analysis.A set of dedicated semi-physical simulation system is built to test the performances of the proposed optimal maneuver ***,the effectiveness of the method proposed in this paper is verified through the comparative analysis of the objective function of the observability of angles-only navigation and the performances of the angles-only navigation filter under different maneuver *** with the cases without orbital maneuver,it is concluded that the tangential filtering accuracy with the optimal orbital maneuver at the terminal time is increased by 35%on average,and the radial and normal filtering accuracy is increased by 30%on average.

关键词： angles-only navigation observability optimal maneuver orbital rendezvous

Upper ocean response to tropical cyclone wind forcing: A case study of typhoon Rammasun(2008)

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Science China Earth Sciences 2015年第9期58卷 1623-1632页

作者： PEI YuHua ZHANG ronghua CHEN DaKe College of Physical and Environmental Oceanography Ocean University of China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyState Oceanic Administration Key Laboratory of Ocean Circulation and Waves Institute of Oceanology Chinese Academy of Sciences

The characteristics of the upper ocean response to tropical cyclone wind （TCW） forcing in the northwestern Pacific were in- vestigated using satellite and Argo data, as well as an ocean general circulation model. In particular, a case study was carried out on typhoon Rammasun, which passed through our study area during May 6-13, 2008. It is found that the local response fight under the TCW forcing is characterized by a quick deepening of the surface mixed layer, a strong latent heat loss to the atmosphere, and an intense upwelling near the center of typhoon, leading to a cooling of the oceanic surface layer that persists as a cold wake along the typhoon track. More interestingly, the upper ocean response exhibits a four-layer thermal structure, including a cooling layer near the surface and a warming layer right below, accompanied by another pair of cooling/warming layers in the thermocline. The formation of the surface cooling/warming layers can be readily explained by the strong vertical mixing induced by TCW forcing, while the thermal response in the thermocline is probably a result of the cyclone-driven upwelling and the associated advective processes.

关键词： tropical cyclone wind forcing upper ocean response satellite and Argo data ocean modeling

Optimal control strategies for stochastically excited quasi partially integrable Hamiltonian systems

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Acta Mechanica Sinica 2007年第3期23卷 311-319页

作者： ronghua Huan Maolin Deng Weiqiu Zhu Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang UniversityHangzhou 310027 China

In this paper two different control strategies designed to alleviate the response of quasi partially integrable Hamiltonian systems subjected to stochastic excitation are proposed. First, by using the stochastic averaging method for quasi partially integrable Hamiltonian systems, an n-DOF controlled quasi partially integrable Hamiltonian system with stochastic excitation is converted into a set of partially averaged It^↑o stochastic differential equations. Then, the dynamical programming equation associated with the partially averaged It^↑o equations is formulated by applying the stochastic dynamical programming principle. In the first control strategy, the optimal control law is derived from the dynamical programming equation and the control constraints without solving the dynamical programming equation. In the second control strategy, the optimal control law is obtained by solving the dynamical programming equation. Finally, both the responses of controlled and uncontrolled systems are predicted through solving the Fokker-Plank-Kolmogorov equation associated with fully averaged It^↑o equations. An example is worked out to illustrate the application and effectiveness of the two proposed control strategies.

关键词： Nonlinear system Stochastic excitation Stochastic averaging Optimal control Dynamical programming

Statistical Analysis of Two-Parameter Generalized BS-Logistic Fatigue Life Distribution

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Journal of Systems Science & Complexity 2019年第4期32卷 1231-1250页

作者： XU Xiaoling WANG ronghua GU Beiqing School of Statistics and Information Shanghai University of International Business and EconomicsShanghai 201620China Mathematics and Science College Shanghai Normal UniversityShanghai 200234China School of Statistics and Information Shanghai University of International Busmess and EconomicsShanghai 201620China

The logarithmic moment estimations of parameters are proposed for two-parameter generalized Birnbaum-Saunders Logistic fatigue life distribution GBS-Logistic(α,β)under the full *** precisions of point estimations are investigated and compared with other point estimations by Monte-Carlo *** approximate interval estimations of parameters are given by using Taylor expansion,and the precisions of approximate interval estimations are investigated by Monte-Carlo ***,several examples show the feasibility of the methods.

关键词： Approximate interval estimation point estimation scale parameter shape parameter two-parameter generalized Birnbaum-Saunders Logistic fatigue life distribution

Experimental observation of deep crust fluid-NaCl aqueous solution at elevated temperatures and pressures and its significance

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Chinese Science Bulletin 1999年第7期44卷 654-660页

作者： ronghua Zhang Shumin Hu Chinese Acad Geol Sci Open Res Lab Geochem Kinet Beijing 100037 Peoples R China

In order to reveal the nature of deep crust fluids, the phase relations of NaCI-saturated solution at high temperatures and pressures in a hydrothermal diamond anvil cell (HDAC)are investigated. Salinity of the solutions observed is about 35%—50%. The temperatures for the observation range from 25 to 850℃ and the pressures from 1 atm to about 1 GPa. A supercritical single phase, liquid phase (L), vapor phase (V), solid phase (H), L + H, H + V + L and the near-critical phases L + V can be observed. A two-phase (L + V) immiscibility field for the NaCI solution has been discovered to lie in a wide range of temperatures and pressures:from 250( ± 3) to 721℃. Within this field there are two parts, where the upper high temperature part of the two-phase regions is very unstable in character. It is possible to observe a 'critical phenomenon'. In some of our experiments an 'explosion' almost constantly occurred at the interface between the liquid and vapor phases, making the interface obscure, and a

关键词： two-phase immiscibility critical phenomenon solution structure.