Geometric Generalization of the Nelder-Mead Algorithm

The permanent magnet flux-switching machine (PMFSM) is one of the most promising machines with magnets inserted into the stator. To determine in which applications the use of PMFSM is promising, it is essential to compare the PMFSM with machines of other types. This study provides a theoretical comparison of the PMFSM with a conventional interior permanent magnet synchronous machine (IPMSM) in the gearless generator of a low-power wind turbine (332 rpm, 51.4 Nm). To provide a fair comparison, both machines are optimized using the Nelder–Mead algorithm. The minimized optimization objectives are the required power of frequency converter, cost of active materials, torque ripple and losses of a generator averaged over the working profile of the wind turbine. In order to reduce the computational time, the substituting profile method is applied. Based on the results of the calculations, the advantages and disadvantages of the considered machines were revealed: the IPMSM has significantly lower losses and higher efficiency than the PMFSM, and the PMFSM requires much less rare-earth magnets and copper and is, therefore, cheaper in mass production.

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Исследование изменения лигандного состава хелата Eu-=SUP=-3+-=/SUP=- методами двухступенчатого лазерного возбуждения люминесценции и компьютерного моделирования кинетики

Журнал технической физики ◽

10.21883/os.2019.02.47194.176-18 ◽

2019 ◽

Vol 126 (2) ◽

pp. 134

Author(s):

И.В. Станишевский ◽

Т.А. Павич ◽

С.М. Арабей

Keyword(s):

Dynamic Model ◽

Rate Constants ◽

Structural Rearrangement ◽

Triphenylphosphine Oxide ◽

Iterative Approximation ◽

Reversible Processes ◽

Experimental Kinetics ◽

Nelder Mead Algorithm ◽

Excitation Method ◽

The Eu

AbstractThe europium(III)–tris(dibenzoylmethane)–triphenylphosphine oxide complex was studied in the polycrystalline state and in toluene at 298 K using the luminescence excitation method with two-stage rectangular pulses with decreasing intensity of stages. Experimental nonmonotonic kinetic curves were numerically simulated within the framework of a four-level dynamic model describing reversible processes in the complex, associated with its structural rearrangement. The maximum correspondence between the experimental and simulated curves was obtained using an iterative approximation performed using the Nelder–Mead algorithm. Based on the obtained numerical values of the rate constants and parameters of the model, experimental kinetics were interpreted, and it was concluded that they are a consequence of the processes associated with changes in the ligand composition of the Eu^3+ chelate.

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AMPLIFIED NELDER-MEAD ALGORITHM FOR SOLVING OPTIMAL REACTIVE POWER PROBLEM

International Journal of Research -GRANTHAALAYAH ◽

10.29121/granthaalayah.v6.i11.2018.1131 ◽

2018 ◽

Vol 6 (11) ◽

pp. 299-306

Author(s):

K. Lenin

Keyword(s):

Simulated Annealing ◽

Power Loss ◽

Reactive Power ◽

Superior Performance ◽

Real Power ◽

Last Stage ◽

Simulation Results ◽

Power Problem ◽

Nelder Mead Algorithm ◽

Prime Solution

This paper presents Hybridization of Simulated Annealing with Nelder-Mead algorithm (SN) is proposed to solve optimal reactive power problem. The proposed Hybridized - Simulated Annealing, Nelder-Mead algorithm starts with a prime solution, which is produced arbitrarily and then the solution is disturbed into partitions. The vicinity zone is created, arbitrary numbers of partitions are selected and variables modernizing procedure is started in order to create a trail of neighbour solutions. This procedure helps the SN algorithm to explore the region around an existing iterate solution. The Nelder- Mead algorithm is used in the last stage in order to progress the most excellent solution found so far and hasten the convergence in the closing stage. The proposed Hybridization of Simulated Annealing with Nelder-Mead algorithm (SN) has been tested in standard IEEE 57,118 bus systems and simulation results show the superior performance of the proposed SN algorithm in reducing the real power loss and voltage profiles are within the limits.

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A Nelder–Mead algorithm-based inverse transient analysis for leak detection and sizing in a single pipe

Water Science & Technology Water Supply ◽

10.2166/ws.2021.030 ◽

2021 ◽

Author(s):

Oussama Choura ◽

Caterina Capponi ◽

Silvia Meniconi ◽

Sami Elaoud ◽

Bruno Brunone

Keyword(s):

Transient Analysis ◽

Experimental Tests ◽

Leak Detection ◽

Calibration Procedure ◽

Second Phase ◽

Viscoelastic Parameters ◽

The Difference ◽

Single Pipe ◽

The University ◽

Nelder Mead Algorithm

Abstract In this paper the results of an experimental validation of a technique for leak detection in polymeric pipes based on the inverse transient analysis (ITA) are presented. In the proposed ITA the Nelder–Mead algorithm is used as a calibration tool. Experimental tests have been carried out in an intact and leaky high-density polyethylene (HDPE) single pipe installed at the Water Engineering Laboratory (WEL) of the University of Perugia, Italy. Transients have been generated by the fast and complete closure of a valve placed at the downstream end section of the pipe. In the first phase of the calibration procedure, the proposed algorithm has been used to estimate both the viscoelastic parameters of a generalized Kelvin–Voigt model and the unsteady-state friction coefficient, by minimizing the difference between the numerical and experimental results. In the second phase of the procedure, the calibrated model allowed the evaluation of leak size and location with an acceptable accuracy. Precisely, in terms of leak location the relative error was smaller than 5%.

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