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Wind farm active power dispatching algorithm based on Grey Incidence

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Global Energy Interconnection 2023年第2期6卷 175-183页

作者： Binbin Zhang Mengxin jia Chaobo Chen Kun Wang jichao Li school of Electronic and Information Engineering Xi’an Technological UniversityXi’an 710021P.R.China

This study proposes a wind farm active power dispatching(WFAPD) algorithm based on the grey incidence method, which does not rely on an accurate mathematical model of wind turbines. Based on the wind turbine start-stop data at different wind speeds, the weighting coefficients, which are the participation degrees of a variable speed system and a variable pitch system in power regulation, are obtained using the grey incidence method. The incidence coefficient curve is fitted by the B-spline function at a full range of wind speeds, and the power regulation capacity of all wind turbines is obtained. Finally, the WFAPD algorithm, which is based on the regulating capacity of each wind turbine, is compared with the wind speed weighting power dispatching(WSWPD) algorithm in MATLAB. The simulation results show that the active power fluctuation of the wind farm is smaller, the rotating speed of wind turbines is smoother, and the fatigue load of highspeed turbines is effectively reduced.

关键词： Wind farm Active power dispatching Grey incidence B-spline function

Linear QSAr regression Models for the Prediction of Bioconcentration Factors of Chloroanilines in Fish by Density Functional Theory

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Chinese journal of Structural Chemistry 2014年第6期33卷 830-834页

作者：冯长君杨伟华 school of Chemistry & Chemical Engineering Xuzhou Institute of Technology school of Chemistry & Chemical Engineering Jiangsu Normal University

Density functional theory（DFT）-B3LYP level with the 6-311G＊＊（d,p） basis set was used to calculate a set of molecular quantum chemical descriptors of 12 chloroanilines. Quantitative structure-activity relationship（QSAr） models of the bioconcentration factors（BCF） of the anilines in fish were established using some of the following calculated descriptors： EHOMO, EnHOMO, ELUMO, EnLUMO, ΔE1（= ELUMO- EHOMO）, ΔE2（= EnLUMO- EnHOMO）, dipole moment（μ）, molecular volume（V）, vibrational energy of 0 K（Ev）, thermodynamic energy（E）, heat capacity（Cv）, entropy（Sm） and the charge of benzene ring（Qph）. Using the variable selection and leaps-and-bounds regression, the quantum chemical descriptors derived directly from the molecular structures were employed to develop a linear QSAr model between the bioconcentration factors（BCF） and two descriptors（Sm, EnHOMO） of 12 chloroanilines. Statistically, the most significant one is a two-parameter linear equation with the correlation coefficient（r^2） of 0.981 and cross-validated correlation coefficient（rcv^2） of 0.967. The established QSAr model has good stability and predictability based on the results from rcv2 of leave-one-out cross-validation, AIC, FIT and tα/2. The quantum chemical analyses were performed from two aspects of frontier molecular orbital and entropy. The results show that two structural describers are crucial to the bioconcentration activity of chloroanilines.

关键词： chloroanilines bioconcentration factor density functional theory quantum chemical describers quantitative structure-activity relationship

HOMOTOPY PErTUrBATIOn SOLUTIOn AnD PErIODICITY AnALYSIS OF nOnLInEAr VIBrATIOn OF THIn rECTAnGULAr FUnCTIOnALLY GrADED PLATES

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Acta Mechanica Solida Sinica 2014年第2期27卷 210-220页

作者： A.Allahverdizadeh r.Oftadeh M.j.Mahjoob M.H.naei school of Engineering - Emerging Technologies University of Tabriz school of Mechanical Engineering College of Engineering University of Tehran Department of Mechanical and Industrial Engineering Northeastern University

In this paper nonlinear analysis of a thin rectangular functionally graded piate is formulated in terms of von-Karman＇s dynamic equations. Functionaily Graded Material （FGM） properties vary through the constant thickness of the plate at ambient temperature. By expansion of the solution as a series of mode functions, we reduce the governing equations of motion to a Duffing＇s equation. The homotopy perturbation solution of generated Duffing＇s equation is also obtained and compared with numerical solutions. The sufficient conditions for the existence of periodic oscillatory behavior of the plate are established by using Green＇s function and Schauder＇s fixed point theorem.

关键词： nonlinear vibration FGM rectangular plate Schauder's fixed point theorem homotopy perturbation method

An intelligent approach for flight risk prediction under icing conditions

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Chinese journal of Aeronautics 2023年第6期36卷 109-127页

作者： Guozhi WAnG Haojun XU Binbin PEI Graduate school Air Force Engineering UniversityXi'an 710038China Aviation Engineering school Air Force Engineering UniversityXi'an 710038China

Flight risk prediction is significant in improving the flight crew's situational awareness because it allows them to adopt appropriate operation strategies to prevent risk expansion caused by abnormal conditions,especially aircraft icing *** flight risk space representing the nonlinear mapping relations between risk degree and the three-dimensional commanded vector(commanded airspeed,commanded bank angle,and commanded vertical velocity)is developed to provide the crew with practical risk ***,the construction of flight risk space by means of computational flight dynamics suffers from certain defects,including slow computing ***,an intelligent approach for flight risk prediction is proposed to address these defects based on neural *** Basis Function neural network(rBFnn)is optimized using Adaptive Particle Swarm Optimization(APSO).To optimize both the parameters and the structure of APSO-rBFnn,a fitness function containing the training accuracy and network structure size is *** experimental results demonstrate that the flight risk predicted by APSO-rBFnn is very close to that obtained via computational flight *** average error(rMSE)is less than 10^(-1).The approach achieves a speedup close to 1000x compared with computational flight *** addition,some flight upset and recovery cases are presented to illustrate the efficiency of the intelligent approach for flight risk prediction.

关键词： Adaptive Particle Swarm Optimization(APSO) Flight risk assessment and prediction Flight risk space Icing conditions radial Basis Function neural network(rBFnn)

Optimization of Composite Wind Turbine Blade Based on Modal Sensitivity

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Transactions of nanjing University of Aeronautics and Astronautics 2021年第1期38卷 153-163页

作者： ZHEnG Yuqiao LIU Zheyan MA Huidong ZHU Kai school of Mechanical and Electronical Engineering Lanzhou University of TechnologyLanzhou 730050P.R.China

This study develops a method for the full-size structural design of blade,involving the optimal layer thickness configuration of the blade to maximize its bending stiffness using a genetic *** differentiation is employed to solve the sensitivity of blade modal frequency to the layer thickness of each part of *** natural frequencies of first-order flapwise and edgewise modes are selected as the optimal *** on the modal sensitivity analysis of all design variables,the effect of discretized layer thickness on bending stiffness of the blade is explored,and 14 significant design variables are filtered to drive the structural *** best solution predicts an increase in natural frequencies of first-order flapwise and edgewise blade modes by up to 12%and 10.4%,*** results show that the structural optimization method based on modal sensitivity is more effective to improve the structural performance.

关键词： composite blade discrete layer thickness modal sensitivity optimal thickness distribution bending stiffness

Metal-free catalytic reduction of aldehydes,ketones,aldimines,and ketimines

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Chinese Chemical Letters 2010年第11期21卷 1314-1317页

作者： Hiroaki Matsuoka Kazuhiro Kondo Graduate school of Medical Sciences Nagoya City University Graduate school of Pharmaceutical Sciences Nagoya City University

The metal-free combination of catalytic amounts of PPh3,B（C6F5）3,and PhSiH_3 can efficiently hydrosilylate aldehydes, ketones,aldimines and ketimines to afford the corresponding reduction products in good yields.

关键词： Metal-free hydrosilylation reduction Ketone Ketimine

Modelling the rheological Properties of Epoxy Asphalt Concrete

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journal of Harbin Institute of Technology(new Series) 2013年第6期20卷 106-111页

作者： Bo Yao Cheng Cheng Xiao Wang Gang Cheng Song-Yu Liu school of Transportation Southeast University

This paper presents an investigation into modelling the rheological properties of epoxy asphalt concrete( EAC) by using the Huet-Sayegh model. Complex modulus tests were conducted on EAC specimens at various temperature and loading frequency conditions. Dynamic modulus and phase angles obtained from the complex modulus tests were used in the construction of the Huet-Sayegh model. The dynamic modulus master curve was developed by the Huet-Sayegh model as well as the Burgers model for comparison purpose. The results showed that EAC exhibits typical rheological behavior whose dynamic modulus decreases with the increase of temperature while increases with the increase of frequency,and phase angles increase with the decrease of frequencies and the increase of temperatures. The Huet-Sayegh model predicts the dynamic modulus master curve of EAC very well and much better than the Burgers model over a wide range of frequencies.

关键词： epoxy asphalt concrete rheological properties complex modulus test Huet-Sayegh modelCLC number:U443.33 Document code:AArticle ID:1005-9113(2013)06-0106-06

Intelligent Integrated Control of Underactuated Mechanical Systems with Second-order nonholonomic Constraints

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High Technology Letters 2003年第3期9卷 81-85页

作者：赖旭芝 Wu Min Cai Zixing She jinhua school of Information Science & Engineering Central South University Changsha Hunan 410083 P.R.China Mechatronics Department Tokyo University of Technology Hachioji Tokyo 192-8580 Japan

This paper describes an intelligent integrated control of an acrobot, which is an underactuated mechanical system with second-order nonholonomic constraints. The control combines a model-free fuzzy control, a fuzzy sliding-mode control and a model-based fuzzy control. The model-free fuzzy controller designed for the upswing ensures that the energy of the acrobot increases with each swing. Then the fuzzy sliding-mode controller is employed to control the movement that the acrobot enters the balance area from the swing-up area. The model-based fuzzy controller, which is based on a Takagi-Sugeno fuzzy model, is used to balance the acrobot. The stability of the fuzzy control system for balance control is guaranteed by a common symmetric positive matrix, which satisfies linear matrix inequalities.

关键词： intelligent integrated control underactuated mechanical systems second-order nonholonomic constraints

Attitude Control of a Flexible Solar Power Satellite Using Self-tuning Iterative Learning Control

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Transactions of nanjing University of Aeronautics and Astronautics 2022年第4期39卷 389-399页

作者： GAO Yuan WU Shunan LI Qingjun school of Aeronautics and Astronautics Sun Yat-sen UniversityShenzhen 518107P.R.China

This paper proposes a self-tuning iterative learning control method for the attitude control of a flexible solar power satellite,which is simplified as an Euler-Bernoulli beam moving in *** orbit-attitude-structure coupled dynamic model is established using absolute nodal coordinate formulation,and the attitude control is performed using two control moment *** order to improve control accuracy of the classic proportional-derivative control method,a switched iterative learning control method is presented using the control moments of the previous periods as feedforward control *** the iterative learning control is a model-free method,the parameters of the controller must be selected *** would be undesirable for complicated systems with multiple control ***,a self-tuning method is proposed using fuzzy *** control frequency of the controller is adjusted according to the averaged control error in one control *** results show that the proposed controller increases the control accuracy greatly and reduces the influence of measurement ***,the control frequency is automatically adjusted to a suitable value.

关键词： iterative learning control attitude control solar power satellite fuzzy control