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Frequency and Offset Online Estimation of Sinusoidal Signals Based on High-Order Nonlinear Continuous Differentiator

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Chinese Journal of Electronics 2017年第3期26卷 579-584页

作者： wang Hongwei ZHANG Wei ZUO Junyi wang heping School of Aeronautics Northwestern Polytechnical University

Real-time parameter identification of sinusoidal signals is an essential research topic due to its broad utilization in both theoretical studies and engineering practice.A tracking differentiator based online estimation framework has been proposed to simultaneously identify frequencies and offset of given multi-sinusoidal *** differentiator is exploited in presented framework to track the time derivatives of measurements which are then utilized to estimate the frequencies and *** introduce a tracking differentiator called high-order nonlinear continuous differentiator into the framework,giving birth to a new estimation *** experiments on both single and two sinusoidal signal are simulated,indicating the superiority of proposed method on both convergent speed and estimation accuracy.

关键词： Frequency estimation Offset estimation High-order nonlinear continuous differentiator Sinusoidal signal Multi-sinusoidal signal

Generalized cubature quadrature Kalman filters:derivations and extensions

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Journal of Systems Engineering and Electronics 2017年第3期28卷 556-562页

作者： Hongwei wang Wei Zhang Junyi Zuo heping wang School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Experimental Aircraft Design and Flight Testing Laboratory of Shaanxi Xi’an 710072China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore

A new Gaussian approximation nonlinear filter called generalized cubature quadrature Kalman filter (GCQKF) is introduced for nonlinear dynamic systems. Based on standard GCQKF, two extensions are developed, namely square root generalized cubature quadrature Kalman filter (SR-GCQKF) and iterated generalized cubature quadrature Kalman filter (I-GCQKF). In SR-GCQKF, the QR decomposition is exploited to alter the Cholesky decomposition and both predicted and filtered error covariances have been propagated in square root format to make sure the numerical stability. In I-GCQKF, the measurement update step is executed iteratively to make full use of the latest measurement and a new terminal criterion is adopted to guarantee the increase of likelihood. Detailed numerical experiments demonstrate the superior performance on both tracking stability and estimation accuracy of I-GCQKF and SR-GCQKF compared with GCQKF.

关键词： cubature rule quadrature rule Kalman filter iterated method QR decomposition nonlinear estimation target tracking

STRONG EQUIVALENCES OF APPROXIMATION NUMBERS AND TRACTABILITY OF WEIGHTED ANISOTROPIC SOBOLEV EMBEDDINGS

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Acta Mathematica Scientia 2020年第6期40卷 1765-1782页

作者： Jidong HAO heping wang School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

In this article,we study multivariate approximation defined over weighted anisotropic Sobolev spaces which depend on two sequences a={a j}j≥1 and b={b j}j≥1 of positive *** obtain strong equivalences of the approximation numbers,and necessary and sufficient conditions on a,b to achieve various notions of tractability of the weighted anisotropic Sobolev embeddings.

关键词： strong equivalences tractability approximation numbers weighted anisotropic spaces analytic Korobov spaces

Experimental study on CO_2/CO of typical lining materials in full-scale fire test

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Chinese Science Bulletin 2007年第9期52卷 1282-1286页

作者： wang Wei ZHANG heping WAN YuTian State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230027 China

Lining materials are widely used in buildings to cover walls and ceilings. Combustible linings may produce a potential high fire hazard in buildings. Once ignited,it propagates fire and accelerates the enclosure fire growth. Two types of lining materials were studied during the tests:block board and plywood. The test was conducted in an ISO 9705 room,where linings were mounted on walls without the ceiling. By changing the heat output of the burner,the ventilation,etc.,the concentrations of CO2/CO of different lining materials were researched. The effect of test conditions on the production of CO2/CO of different lining materials was investigated,and useful experimental data were provided for the further development of numerical modeling to simulate enclosure fire growth lined with combusti-ble materials.

关键词：典型装饰材料足尺火灾试验 CO2 CO 有害气体实验研究

Numerical Simulation Study of Oil-Water Emulsion Separation in an Ultrasonic Field:Effect of Coupling between Acoustic and Flow Field Parameters

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 116-125页

作者： wang heping Lin Yinchao Li Yanggui Zhang Xiaohang Wu Yi Key Laboratory of Engineering Mathematics and Advanced Computing of Nanchang Institute of Technology School of SciencesNanchang Institute of TechnologyNanchang 330099People’s Republic of China Dongguan Key Laboratory of Kunpeng Computing School of Computer ScienceGuangdong University of Science&TechnologyDongguan 523083China State Key Laboratory of Plateau Ecology and Agriculture Qinghai UniversityXining 810016China

In this study,the separation and coalescence of oil-in-water emulsions are explored in an ultrasonic field using the lattice Boltzmann *** simulating the propagation of ultrasonic waves,this study focuses on examining the effects of acoustic wave frequency,the ratio of oil to water components,and the aspect ratio of the boundary on the emulsification and separation processes of oil-water *** following conclusions are drawn.①Frequency affects the speed of oil droplet separation,leading to an increase in droplet size over *** droplets are found near the source,while smaller droplets are distributed throughout the wave web.②As the boundary aspect ratio increases,the emulsification efficiency of the droplets weakens,and the system takes longer to stabilize.③Emulsions with a higher component of oil can better resist acoustic waves.④At the same acoustic frequency,longer wavelength ultrasonic fields promote the formation of uniformly distributed,smaller oil droplets,which is beneficial to the storage of *** numerical simulation results offer insights for optimizing conditions for oil-in-water separation and serve as a numerical reference for the study of oil-in-water emulsion separation in ultrasonic environments.

关键词： lattice Boltzmann method phase separation ultrasound field

Novel Logarithmic Non-Singular Terminal Sliding Mode and ItsApplication in Attitude Control of QTR

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Journal of Harbin Institute of Technology(New Series) 2019年第5期26卷 51-59页

作者： Haibo Liu heping wang Junlei Sun College of Aeronautics Northwestern Polytechnical University Xi'an 710072 China Shenzhen Research Institute of Northwestern Polytechnical University Shenzhen 518057 Guangdong China

In this study we mainly focus on the attitude control problem of a quad tilt rotor aircraft with respect to unknown external disturbance. We propose a class of control methods based on a novel logarithmic fast non singular terminal sliding surface a new fast reaching law and extended state disturbance observer. A logarithmic non singular terminal sliding surface is used owing to its convergence in finite time and significant robustness. A fast reaching law with two order characteristics of the sliding mode is designed. This reaching law can be used reduce the convergence time of traditional reaching law. In addition the extended state disturbance observer is utilized for online estimation and to compensate for system disturbance. The simulation experiment results show that the control strategy proposed in this paper outperforms the traditional non singular fast sliding mode control.

关键词： tilt rotor nonsingular sliding mode control attitude control reaching law extended state disturbance observer

Optimal Recovery of Functions on the Sphere on a Sobolev Spaces with a Gaussian Measure in the Average Case Setting

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Analysis in Theory and Applications 2015年第2期31卷 154-166页

作者： Zexia Huang heping wang School of Mathematical Sciences Capital Normal University School of Science Xihua University

In this paper, we study optimal recovery （reconstruction） of functions on the sphere in the average case setting. We obtain the asymptotic orders of average sampling numbers of a Sobolev space on the sphere with a Gaussian measure in the Lq （S^d-1） metric for 1 ≤ q ≤ ∞, and show that some worst-case asymptotically optimal algorithms are also asymptotically optimal in the average case setting in the Lq （S^d-1） metric for 1 ≤ q ≤ ∞.

关键词： Optimal recovery on the sphere average sampling numbers optimal algorithm,Gaussian measure.

Numerical Analysis of Aerodynamic Characteristics of the HALE Diamond Joined-Wing Configuration UAV

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Journal of Harbin Institute of Technology(New Series) 2019年第6期26卷 31-45页

作者： Junlei Sun heping wang Zhou Zhou Shan Lei School of Aeronautic Northwestern Polytechnical UniversityXi'an 710072China R&D Center AVIC Xi'an Aircraft Industry(Group)Company Ltd.(China)Xi'an 710089China

The investigation on the aerodynamic characteristics of the high-attitude long-endurance (HALE) Diamond Joined-Wing configuration unmanned aerial vehicle ( UAV) was carried out by the theoretical analysis method and numerical simulation. Research indicates that as the wing of the UAV is composed of the front wing and the after wing, the after wing has the ability to transmit the front wing's boundary layer to the after wing root which can inhibit the front wing's flow separation. Although the front wing was affected by the retardation of the after wing, the aerodynamic performance of the front wing was better than that of alone front wing in most cases. The after wing was also affected by the wake and downwash of the front wing, and its aerodynamic performance was greatly decreased. The characteristic curve of the pitching moment of the UAV had nonlinear characteristics. The flow field structure of the after wing changed by the front wing wake direct sweep and flow separation at the after wing root were the main reasons that non-linear ′rise′phenomenon occurred in two segments ( α = 0° and α = 8° ) of the characteristic curve of pitching moment. Moreover, coupling of the flow separation characteristic of the front wing and the after wing resulted in the pitching moment ′pitchup′ phenomenon. The lateral-directional static stability of the flat layout was weak. The HALE Diamond Joined-Wing configuration UAV ' s aerodynamic performance can be improved and the problems in engineering applications can be effectively alleviated by adjusting the overall layout parameters.

关键词： Diamond Joined-Wing configuration HALE numerical simulation aerodynamic characteristic layout parameters

The enhancing effect and promoting mechanisms of the stereoisomeric monoterpene alcohol esters as enhancers for drugs with different physicochemical properties

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Asian Journal of Pharmaceutical Sciences 2022年第1期17卷 139-152页

作者： heping wang Yan Li Chunyan wang Jing wang Bo Ren Xiaona Li Mingzhu Li Dandan Geng Chensi Wu Ligang Zhao School of Pharmacy North China University of Science and TechnologyTangshan 063000China Dept of Pharmacy Tangshan Maternal and Child Health HospitalTangshan 063000China Tangshan key laboratory of novel preparations and drug release technology Tangshan 063000China

To explore the structure-activity connections of amphiphilic permeation enhancers containing the length of the hydrophobic chains as well as the properties of the polar head,O-acylgeraniol and O-acylnerol derivatives were synthesized from geraniol/nerol(cis-isomer of geraniol) and pharmaceutical excipient acids in this research. Their promotion of the percutaneous absorption of three drugs as the model, flurbiprofen(FP), isosorbide dinitrate(ISDN) and donepezil(DNP), which were selected based on their physicochemical properties,was tested by in vitro skin penetration and in vivo. Molecular simulation, ATR-FTIR, CLSM and histological observation were implement to evaluate the mode of action of the *** results indicated that(E)-3,7-dimethyl-2,6-octadien-1-yl tetradecanoate(GER-C14, trans-)achieved the highest enhancement ability for the three drugs;additionally, the in vivo results obtained were in good correlation with the in vitro data. Molecular docking results suggested that enhancers loosen the hydrogen bonds between ceramides, and the results of molecular simulation indicated that GER-C14, NER-C14 could insert into the middle of the lipid bilayer to form an independent phase. According to ATR-FTIR and histological evaluation, the enhancers extracted lipids and influenced the protein region, thereby disturbing the skin array. In addition, CLSM described the dynamic effects of enhancers on lipids between stratum corneum(SC) cells. In conclusion, GER-C14 had a better penetration promotion effect, which broadened our understanding of stereoisomeric penetration enhancers.

关键词： O-acylgeraniol derivatives O-acylnerol derivatives Transdermal drug delivery system In vitro and in vivo correlation Enhancing mechanism