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Reduced nonlinear unknown inputs observer using mean value theorem and patternsearch algorithm

AUTOMATICA 2020年 112卷

作者： Ben Messaoud, Ramzi Ctr Rech & Technol Energie Lab Nanomat & Syst Energies Renouvelables BP 95 Hammam Lif 2050 Tunisia

This paper is devoted to reduced order of unknown inputs observer design. A new structure is proposed, and it includes the dynamics of the estimation error and the uncertain parameters beta integrated into the mean value theorem. The pattern search algorithm will be used for the determination of beta parameters and the observer design. The stability study relies on the use of the quadratic Lyapunov functions. The observer gain is systematically determined by using an analytical method. A second method will be proposed for the gain determination, and it is based on the LMI technical and the polytopic transformation. The case of outputs affected by the disturbances is also studied. Finally, a numerical example is provided to illustrate the performance of the proposed approach. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： pattern search algorithm Nonlinear reduced observer Nonlinear system Mean value theorem State estimation

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Coordinated optimal control of active power of wind farms considering wake effect

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ENERGY REPORTS 2022年 8卷 84-90页

作者： Shen, Yu Xiao, Tannan Lv, Qifeng Zhang, Xuemin Zhang, Yangfan Wang, Yimei Wu, Jinfang State Grid Xin Yuan Co Zhangjiakou Wind & Solar Power Energy Demonstrat Jianshe West St 15 Zhangjiakou 075000 Peoples R China Tsinghua Univ Shuangqin Rd 30 Beijing 100084 Peoples R China State Grid Jibei Elect Power Co Ltd Elect Power Res Inst Caishikou South St 56 Beijing 100054 Peoples R China

In a large-scale wind farm, under the influence of the wake effect, the single-machine maximum power extraction control strategy would not be able to function at the ideal optimal value. It is important to study the coordinated operation strategy of the wind farm under the wake effect to improve the output power of wind farms and improve the economic benefit. In this paper, a practical wake model called the PARK model is used and a wake superposition model based on energy balance is derived. Based on these models, an optimization problem is formulated to maximize the output power of the wind farm considering the wake effect. Taking the Horns Rev offshore wind farm as an example, the stochastic points method, particle swarm optimization, and the pattern search algorithm are implemented and compared with the single-machine maximum power extraction algorithm. Test results show that the particle swarm optimization and the pattern search algorithm have better performance. The output power of the wind farm increases by about 10 percent. The particle swarm optimization requires less computation while the pattern search algorithm obtains better and more practical results. Finally, the pattern search algorithm is used to improve economic benefits under different wind conditions. (C) 2021 The Authors. Published by Elsevier Ltd.

关键词： Wake effect Coordinated operation strategy Particle swarm optimization pattern search algorithm

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Frequency and pattern reconfigurable rectangular patch antenna using single PIN diode

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AEU-INTERNATIONAL JOURNAL OF ELECTRONICS AND COMMUNICATIONS 2020年 125卷 153370-153370页

作者： Palsokar, Anuradha A. Lahudkar, S. L. Rajarshi Shahu Coll Engn Pune Maharashtra India Imperial Coll Engn & Res Pune Maharashtra India

The paper presents the design of a frequency and pattern reconfigurable rectangular patch antenna using a single PIN diode switch. The use of single PIN diode reduces the complexity of the biasing network required for the diode. The proposed antenna can work in two different modes and resonates at 2.47 GHz, 3.8 GHz, and 5.36 GHz with the capability to change the radiation pattern. In this design biasing lines required for biasing of the diode are placed away from the radiating structure and the pattern search algorithm is used for the optimization of antenna feed for achieving impedance matching. These are the two improvisations made in the presented design as compared to the existing designs in literature. (C) 2020 Elsevier GmbH. All rights reserved.

关键词： Frequency reconfigurable antenna Rectangular patch antenna pattern reconfigurable antenna pattern search algorithm PIN diode

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Generalized pattern searches with derivative information

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MATHEMATICAL PROGRAMMING 2004年第1期100卷 3-25页

作者： Abramson, MA Audet, C Dennis, JE Air Force Inst Technol Wright Patterson AFB OH 45433 USA Ecole Polytech Dept Math & Genie Ind Montreal PQ H3C 3A7 Canada GERAD Dept Math & Genie Ind Montreal PQ H3C 3A7 Canada Rice Univ Dept Comp & Applied Math Seattle WA 98136 USA

A common question asked by users of direct search algorithms is how to use derivative information at iterates where it is available. This paper addresses that question with respect to Generalized pattern search (GPS) methods for unconstrained and linearly constrained optimization. Specifically, this paper concentrates on the GPS POLLstep. Polling is done to certify the need to refine the current mesh, and it requires O(n) function evaluations in the worst case. We show that the use of derivative information significantly reduces the maximum number of function evaluations necessary for POLLsteps, even to a worst case of a single function evaluation with certain algorithmic choices given here. Furthermore, we show that rather rough approximations to the gradient are sufficient to reduce the POLLstep to a single function evaluation. We prove that using these less expensive POLLsteps does not weaken the known convergence properties of the method, all of which depend only on the POLLstep.

关键词： pattern search algorithm linearly constrained optimization surrogate-based optimization nonsmooth optimization gradient-based optimization

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GMRVV_m-SVR model for financial time series forecasting

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EXPERT SYSTEMS WITH APPLICATIONS 2010年第12期37卷 7813-7818页

作者： Jiang, Hui Wang, Zhizhong Cent S Univ Sch Math Sci & Comp Technol Changsha 410075 Hunan Peoples R China Huizhou Univ Dept Math Sci Huizhou 516007 Guangdong Peoples R China

The complex model GMRVV(m)-SVR has been adopted to predict financial time series with such characteristics as small sample size, poor information, non-stationary, high noise and non-linearity. In order to construct GMRVV(m)-SVR, the m-root grey model with revised verge value (GMRVV(m)) has been introduced and modified by support vector regression based on the calculation of the residual error sequence between predicted values and original data. Due to the recent data points providing more information than distant data points, more importance has been attached to the punishment parameter C of recent data points in support vector regression. Simultaneously, the parameter epsilon in epsilon-insensitive loss function has been determined according to smoothing overshooting. pattern search (PS) algorithm has been carried out to tune free parameters. A real experimental result shows that the complex model can achieve comparative accurate prediction as well as smoothing overshooting in financial time series prediction. (C) 2010 Elsevier Ltd. All rights reserved.

关键词： m-root grey model Verge value conditions Support vector regression Smoothing overshooting pattern search algorithm

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A general method for active surface adjustment of cable net structures with smart actuators

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SMART STRUCTURES AND SYSTEMS 2015年第1期16卷 27-46页

作者： Wang, Zuowei Li, Tuanjie Xidian Univ Sch Electromech Engn Xian 710071 Shaanxi Peoples R China

Active surface adjustment of cable net structures is becoming significant when large-size cable net structures are widely applied in various fields, especially in satellite antennas. A general-duty adjustment method based on active cables is proposed to achieve active surface adjustment or surface profile reconfiguration of cable net structures. Piezoelectric actuators and voice coil actuators are selected for constructing active cable structures and their simplified mechanical models are proposed. A bilevel optimization model of active surface adjustment is proposed based on the nonlinear static model established by the direct stiffness method. A pattern search algorithm combined with the trust region method is developed to solve this optimization problem. Numerical examples of a parabolic cable net reflector are analyzed and different distribution types of active cables are compared.

关键词： active surface adjustment cable net structure smart actuator direct stiffness method pattern search algorithm

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Optimization of Source Modeling From Phaseless Near-Field Scanning Based on SVD-Defined Eigenmodes

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IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY 2024年第6期66卷 1876-1887页

作者： Tsai, Min-Hsu Qian, Hong-Wen Chen, Wei-Kai Huang, Ming-Chung Liu, Jen-Chieh Wu, Ruey-Beei Natl Taiwan Univ Dept Elect Engn Taipei 10617 Taiwan Natl Taiwan Univ Grad Inst Commun Engn Taipei 10617 Taiwan Realtek Semicond Corp Hsinchu 30076 Taiwan Himax Technol Xinshi 74148 Taiwan

This article proposes a procedure for reconstructing dipole moment models from magnitude-only near-field scanned magnetic fields. Preprocessing uses a finite-impulse response filter to deblur the 2-D divergence of the magnetic fields to locate the dipoles. The procedure defines the modes of the dipole distribution using singular value decomposition. Based on mode decomposition, the modal coefficients are optimized through a pattern search algorithm to obtain the dipole moments. Compared with existing methods, this method reconstructs better phase information in high-noise situations. Using mode decomposition circumvents the problem of a limited number of dipoles that can be solved by existing optimization methods. Real experiments using high-resolution near-field scanned data show that the main emission sources of individual traces inside an integrated circuit (IC) chip can be distinguished through the proposed procedure.

关键词： Magnetic moments Magnetic resonance imaging Optimization Finite impulse response filters Noise Integrated circuit modeling Phase measurement Electromagnetic interference (EMI) equivalent dipole model near-field scanning optimization pattern search algorithm phase-retrieval singular value decomposition (SVD)

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The improved NURBS-based C² PH spline curve contour following task with PDFF controller

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INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 2014年第5-8期70卷 995-1007页

作者： Jahanpour, Javad Ghadirifar, Amir Islamic Azad Univ Mashhad Branch Dept Mech Engn Mashhad Iran

In this paper, using the specifications of nodal points on a nonuniform rational B-spline (NURBS) curve of three degrees with respect to NURBS curve parameter and defining the coefficients for the velocity and acceleration vectors on these points, a new method is presented to design a tool path via C-2 PH spline curves. Values of the velocity/acceleration vector coefficients corresponding to the nodal points on the original NURBS curve are computed by pattern search algorithm. To this end, the normal distance between the constructed C-2 PH spline curve and its corresponding original NURBS curve is considered as the objective function. Using combination of the time-dependent feed rate interpolation in the acceleration/deceleration phase of the motion and the constant feed rate interpolation in the middle region of the motion, the position commands of the designed NURBS-based C-2 PH spline curve are generated. Several improved NURBS-based C-2 PH spline curve following tasks were implemented with pseudo-derivative feedback feed forward (PDFF) controller. The experimental and simulation results confirm that the devised interpolator with designed PDFF controller is not only feasible for machining the complicated tool path represented in the improved NURBS-based C-2 PH spline form but also yields satisfactory contouring performance under variable feed rate.

关键词： PH curves NURBS curves Nodal points Velocity/acceleration vector coefficients pattern search algorithm PDFF controller

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A novel acc-jerk-limited NURBS interpolation enhanced with an optimized S-shaped quintic feedrate scheduling scheme

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INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 2015年第9-12期77卷 1889-1905页

作者： Jahanpour, Javad Alizadeh, Mohammad Reza Islamic Azad Univ Mashhad Branch Dept Mech Engn Mashhad Iran

This paper presents a new adaptive acc-jerk-limited nonuniform rational B-spline (NURBS) interpolation method based on an optimized S-shaped C-2 quintic feedrate planning scheme. At first, the modified quintic feedrate profile for each sharp corner during the acceleration/deceleration (acc/dec) stage is constructed. To this end, two feedrate slope correction coefficients (FSCC) are introduced for zero end point acceleration and jerk conception in acc/dec stage of each sharp corner. Also, a new algorithm is recommended to compute the acc/dec stage traverse time with respect to the deceleration starting time in this paper. Then, the modified quintic feedrate scheduling scheme equipped with the FSCC is improved for the tool path containing several sharp corners. The FSCC and the deceleration starting times corresponding to all sharp corners are evaluated using an optimization method such that the total machining time to be minimized. In this paper, the pattern search algorithm equipped with the nonlinear constraint function including the acceleration and jerk limitations Matlab code is used for obtaining the optimized parameters to accomplish the acc-jerk-limited feedrate scheduling scheme along the tool path. The proposed interpolation method is performed for several case studies and compared with the previously published methods to evaluate the effectiveness of the designed adaptive acc-jerk-limited feedrate scheduling scheme. The simulation results demonstrate that the proposed interpolation algorithm is capable for providing a smooth feedrate transition for all stages of motion along the tool path and yields satisfactory performances such as total machining time and the interpolation steps.

关键词： Adaptive NURBS interpolation Confined chord error Acc-jerk limited Modified S-shaped C-2 quintic feedrate pattern search algorithm

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Optimum Hydraulic Design of Inverted Syphon Structure in Sewer System with a Case Study of Al-Hashmea Sewer Project

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KSCE JOURNAL OF CIVIL ENGINEERING 2021年第9期25卷 3346-3358页

作者： Al-Juboori, Muqdad Al-Murshidi, Kareem James Cook Univ Coll Sci & Engn Douglas Qld 4811 Australia Univ Kufa Engn Coll Civil Engn Dept Kufa 540011 Iraq

An inverted syphon is a hydraulic structure utilized to convey open channel flow under obstructions. This study focuses on identifying the safest and optimum design of a sewage inverted syphon to avoid intersection problems with immovable infrastructures. Hydraulic design requirements, inlet and outlet distribution rooms features and protection of expected loads on syphons' pipes were taken under consideration in formulation the optimization model. Further, different pipes' material, many levels of the design variables and parameters were incorporated in the model to highlight the effect of each variable on the optimum design. The objective function was the minimum construction cost, and the design requirements were presented as constraints in the model. Results demonstrated that the optimum design for discharges ranging from 0.38 m(3)/sec to 0.95 m(3)/sec was Poly Vinyl Chloride (PVC) syphon, but for other discharges the reinforced concrete type was the optimum. Compared to traditional design, the optimum solutions provide a significant cost reduction. Concrete inverted syphon was the optimum possible solution to solve intersection problem of Al-Hashmea sewer project to pass sewage flow under the railway.

关键词： Hydraulic structures Inverted syphon pattern search algorithm Fmincon algorithm Optimization

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