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Sensor fault-tolerant observer applied in UAV anti-skid braking control under control input constraint

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Journal of Systems Engineering and Electronics 2017年第1期28卷 126-136页

作者： Hui Sun Jianguo Yan Yaohong Qu jie ren School of Automation Northwestern Polytechnical University Chengdu Aircraft Industrial (Group) Co. Ltd.

This paper proposes a method for addressing the problem of sensor fault-tolerant control (FTC) for anti-skid braking systems (ABSs). When the wheel velocity sensor of the ABS for unmanned aerial vehicles (UAVs) becomes faulty, wheel velocity failure and feedback instability may occur. Firstly, a fault diagnosis and isolation (FDI) method based on a sliding mode observer approach is introduced to detect and isolate the fault of the sensor. When the wheel velocity sensor is in healthy conditions, the observer works in a diagnosis mode. If faults occur in the sensor, it acts as a wheel velocity estimator. Secondly, an FTC strategy, adopting a feedback compensation structure, is designed with input control constraints. In addition, based on the FDI result, a terminal sliding mode (TSM) controller is designed to guarantee that slip-ratio tracks its appropriate reference values in situations where runways change conditions during landing. The control system switches automatically from control using a wheel velocity sensor to sensorless control mode, so the observer-based FTC scheme is established. It is logical that the ABS keeps observed-state and remains stable when the wheel velocity sensor is broken and during external disturbance. Finally, simulation results show the effectiveness of the proposed method. © 1990-2011 Beijing Institute of Aerospace Information.

关键词： Braking Control systems Failure analysis Fault tolerance Feedback Sensorless control Sliding mode control Unmanned aerial vehicles (UAV) Velocity Wheels

Halodemetallation of (Z)-1-[2-(Triarylstannyl)vinyl]-cyclooctanol and Correlation of Proton Chemical Shift with Electronegativity

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Chemical Research in Chinese Universities 2002年第3期18卷 372-374页

作者： ren Yu-jie YU Li-mei YANG Xue-feng CHEN Hui-lin BAI Ri-xia Department of Chemistry Dalian University of TechnologyDalian 116024P.R.China Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023P.R.China Dalian Nationality College Dalian 116600P.R.China

Organotin compounds have attracted attention as an optimal model for antitumour agents due to the function of the interesting intramolecular O→Sn coordination. Our recent concern has been focused on the preparation of (Z)-l-[2-(tri-arylstannyl)vinyl]-cyclooctanolM. In order to find more appropriate compounds used as anticancer agents and explore the effect of the coordinate O→Sn interaction to the antitumor activity, the new compounds were halodemetallated and charac-terized.

关键词： Organotin Halodemetallation Correlation Chemical shift Electronegativity

Joint application of feature extraction based on EMD-AR strategy and multi-class classifier based on LS-SVM in EMG motion classification

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1246-1255页

作者： YAN Zhi-guo WANG Zhi-zhong ren Xiao-mei Departmen of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200030 China

This paper presents an effective and efficient combination of feature extraction and multi-class classifier for motion classification by analyzing the surface electromyografic(sEMG) signals. In contrast to the existing methods,considering the non-stationary and nonlinear characteristics of EMG signals,to get the more separable feature set,we introduce the empirical mode decomposition(EMD) to decompose the original EMG signals into several intrinsic mode functions(IMFs) and then compute the coefficients of autoregressive models of each IMF to form the feature set. Based on the least squares support vector machines(LS-SVMs) ,the multi-class classifier is designed and constructed to classify various motions. The results of contrastive experiments showed that the accuracy of motion recognition is improved with the described classification scheme. Furthermore,compared with other classifiers using different features,the excellent performance indicated the potential of the SVM techniques embedding the EMD-AR kernel in motion classification.

关键词： Electromyografic signal Empirical mode decomposition (EMD) Auto-regression model Wavelet packet transform Least squares support vector machines (LS-SVM) Neural network

Analysis of volatile compounds in Herba Asari by single-drop micro-extraction gas chromatography mass spectrometry

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Chinese Chemical Letters 2013年第6期24卷 542-544页

作者： Guan-jie Wang mei-Ling Qi National Institutes for Food and Drug Control School of Chemistry Beijing Institute of Technology

A rapid headspace single-drop micro-extraction（mix） gas chromatography mass spectrometry（SDMEGC -MS） for the analysis of the volatile compounds in Herba Asari was developed in this study.A mixed solvent of n-tridecane and butyl acetate（1：1） was finally used for the extraction at 70 C for 15 min with sample amount of 0.750 g and 100 mesh particle *** the determined conditions,the pound samples of Herba Asari were directly applied for the ***-GC-MS,SPME-GC-MS and SD-GCMS methods were compared and the results showed that SDME-GC-MS method was a simple, inexpensive and effective way to measure the volatile compounds in Herba Asari and could be used for the analysis of volatile compounds in complex samples.

关键词： Single-drop micro-extraction Herba Asari Volatile compounds Traditional Chinese medicine

Determinations of the Configuration of C-20 in Derivatives of Adynerin Using DFT/HF Methods

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Chemical Research in Chinese Universities 2007年第5期23卷 592-597页

作者： HUA Yan ren jie CHEN Chang-xiang ZHU Hua-jie Organic Synthesis and Natural Product Laboratory State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Science Kunming 650204 P. R. China Southwest Foresty University Kunming 650224 P. R. China

The configurations of C-20 in derivatives of novel 5α-adynerin type,co-existing glycoside in pair,were identified with the calculated chemical shifts of carbon at the B3LYP/6-311＋G（2d,p）*** glycosides are unusual ... 详细信息

关键词： Configuration determination Adynerin derivative B3LYP GIAO NMR computation

Sub-pixel motion estimation using phase correlation: comparisons and evaluations

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International Journal of Intelligent Computing and Cybernetics 2016年第4期9卷 394-405页

作者： jie ren Huimin Zhao Jinchang ren Shi Cheng College of Electronics and Information Xi’an Polytechnic UniversityXi’anChina School of Electronic and Information Engineering Guangdong Polytechnic Normal UniversityGuangzhouChina Department of Electronic and Electrical Engineering University of StrathclydeGlasgowUK School of Computer Science Shaanxi Normal UniversityXi’anChina

Purpose-Effective and robust motion estimation with sub-pixel accuracy is essential in many image processing and computer vision *** to its computational efficiency and robustness in the presence of intensity changes as well as geometric distortions,phase correlation in the Fourier domain provides an attractive solution for global motion estimation and image *** paper aims to discuss these ***/methodology/approach-In this paper,relevant sub-pixel strategies are categorized into three classes,namely,single-side peak interpolation,dual-side peak interpolation and curve *** well-known images“Barbara”and“Pentagon”were used to evaluate the performance of eight typical methods,in which Gaussian noise was attached in the synthetic ***-For eight such typical methods,the tests using synthetic data have suggested that considering dual-side peaks in interpolation or fitting helps to produce better *** addition,dual-side interpolation outperforms curve fitting methods in dealing with noisy ***,Gaussian-based dual-side interpolation seems the best in the ***/value-Based on the comparisons of eight typical methods,the authors can have a better understanding of the phase correlation for motion *** evaluation can provide useful guidance in this context.

关键词： Linear interpolation Motion estimation Phase correlation Sub-pixel registration

The F-box protein HAWAIIAN SKIRT is required for mimicry target-induced microRNA degradation in Arabidopsis

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Journal of Integrative Plant Biology 2019年第11期61卷 1121-1127页

作者： Jun mei Ning Jiang Guodong ren State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering School of Life SciencesFudan UniversityShanghai 200438China Laboratory of Population&Quantitative Genetics Institute of Genetics and BiostatisticsSchool of Life SciencesFudan UniversityShanghai 200438China

Mimicry target-directed micro RNA degradation is widespread and highly conserved among eukaryotes. However, little is known about its mechanism of action. In this letter, by using STTM160(target mimic of mi R160) as a reporter, we show that dysfunction of HAWAIIAN SKIRT(HWS) suppresses the pleiotropic phenotype of STTM160. Small RNA sequencing and Northern blot analyses suggested that HWS only affects a subset of micro RNAs. Intriguingly,we identified a stable coexistence of mi R160/mi R399 and their mimicry targets within the AGO1 complex when HWS is compromised, pointing to a possible role of HWS in the clearance of RNA-induced silencing complexes associated with mimicry target.

关键词： mimicry letter HAWAII

Potential effects of the nursing work environment on the work-family conflict in operating room nurses

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World Journal of Clinical Cases 2021年第26期9卷 7738-7749页

作者： Chun-mei Fu jie Ou Xiao-mei Chen mei-Ye Wang Department of Ophthalmology Hainan West Central HospitalDanzhou 571700Hainan ProvinceChina Department of Critical Care Medicine Hainan General HospitalHaikou 570311Hainan ProvinceChina Operation Room The Second Affiliated Hospital of Hainan Medical CollegeHaikou 570311Hainan ProvinceChina Department of General Practice Hainan West Central HospitalDanzhou 571700Hainan ProvinceChina

BACKGROUND The nursing working environment is an important subsystem in the hospital environment.A good working environment could have a positive impact on ***,the work-family conflict and unsatisfactory working environment could significantly reduce their working enthusiasm,efficacy as well as the overall quality of the nursing,increase their fatigue,and thereby compromise their career *** To explore the possible status quo and to analyze the correlation between work environment perception and the work-family conflict among nurses in the operating *** A total of 312 operating room nurses from two first-class hospitals at Grade 2 and two first-class hospitals at Grade 3 in China from May to September 2017 were included in this research using the cluster sampling *** data,including the general information questionnaire,the practice environment scale of the nursing work index(PES-NWI),and the work-family conflict scale,were systematically *** correlation analysis was applied to analyze the correlation between the two scores,with influencing factors analyzed by hierarchical regression *** A total of 312 questionnaires were issued,and the response rate and effective questionnaire rate were both 96.15%(300/312).The total scores of the PES-NWI scale and the work-family conflict scale were 3.07±0.43(vs maximum up to 4 points)and 52.32±8.79(vs maximum up to 90 points),*** scores of the PES-NWI scale were negatively correlated with that of work-family conflict scale(all P<0.05).The perception of the nursing work environment and the number of night shifts per month were the major factors contributing to the workfamily conflict(all P<0.05).CONCLUSION The nursing work environment and the work-family conflict among nurses in the operating room were both found at a medium level with a negative correlation between the two.

关键词： Operating room nurses Perception of nursing work environment Workfamily conflict Correlation Influencing factors

Steady-state entanglement and heat current of two coupled qubits in two baths without rotating wave approximation

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Chinese Physics B 2019年第6期28卷 72-80页

作者： mei-Jiao Wang Yun-jie Xia College of Physics and Engineering Qufu Normal UniversityQufu 273165China Shandong Provincial Key Laboratory of Laser Polarization and Information Technology Qufu Normal UniversityQufu 273165China

We study the steady-state entanglement and heat current of two coupled qubits, in which two qubits are connected with two independent heat baths(IHBs) or two common heat baths(CHBs). We construct the master equation in the eigenstate representation of two coupled qubits to describe the dynamics of the total system and derive the solutions in the steadystate with stronger coupling regime between two qubits than qubit–baths. We do not make the rotating wave approximation(RWA) for the qubit–qubit interaction, and so we are able to investigate the behaviors of the system in both the strong coupling regime and the weak coupling regime, respectively. In an equilibrium bath, we find that the entanglement decreases with the bath temperature and energy detuning increasing under the strong coupling regime. In the weak coupling regime,the entanglement increases with coupling strength increasing and decreases with the bath temperature and energy detuning increasing. In a nonequilibrium bath, the entanglement without RWA is useful for entanglement at lower *** also study the heat currents of the two coupled qubits and their variations with the energy detuning, coupling strength and low temperature. In the strong(weak) coupling regime, the heat current increases(decreases) with coupling strength increasing when the temperature of one bath is lower(higher) than the other, and the energy detuning leads to a positive(negative) effect when the temperature is low(high). In the weak coupling regime, the variation trend of heat current is opposite to that of coupling strength for the IHB case and the CHB case.

关键词： steady-state entanglement equilibrium and nonequilibrium baths heat current rotating wave approximation