On using high-order polynomial curve fits in the quasi-steady theory for square-cylinder galloping

A high-order polynomial fitting method is proposed to accelerate the computation of double-Gaussian fitting in the retrieval of the Brillouin frequency shifts (BFS) in optical fibers showing two local Brillouin peaks. The method is experimentally validated in a distributed Brillouin sensor under different signal-to noise ratios and realistic spectral scenarios. Results verify that a sixth-order polynomial fitting can provide a reliable initial estimation of the dual local BFS values, which can be subsequently used as initial parameters of a nonlinear double-Gaussian fitting. The method demonstrates a 4.9-fold reduction in the number of iterations required by double-Gaussian fitting and a 3.4-fold improvement in processing time.

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Novel parameter estimation of high-order polynomial phase signals using group delay

Signal Processing ◽

10.1016/j.sigpro.2021.108011 ◽

2021 ◽

Vol 183 ◽

pp. 108011

Author(s):

Xiaodong Jiang ◽

Siliang Wu ◽

Yuan Chen

Keyword(s):

Parameter Estimation ◽

Group Delay ◽

High Order ◽

Polynomial Phase ◽

Polynomial Phase Signals ◽

Order Polynomial

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Polynomial Moving Fitting Method for Edge Identification

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.308-310.2560 ◽

2011 ◽

Vol 308-310 ◽

pp. 2560-2564 ◽

Cited By ~ 2

Author(s):

Xiang Rong Yuan

Keyword(s):

Edge Detection ◽

Curve Fitting ◽

Polynomial Function ◽

High Order ◽

Polynomial Fitting ◽

Fitting Method ◽

Order Polynomial ◽

Better Than ◽

Low Order

A moving fitting method for edge detection is proposed in this work. Polynomial function is used for the curve fitting of the column of pixels near the edge. Proposed method is compared with polynomial fitting method without sub-segment. The comparison shows that even with low order polynomial, the effects of moving fitting are significantly better than that with high order polynomial fitting without sub-segment.

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Manufacturing Process for Circular-Arc Curvilinear Cylindrical Gears with Predesigned Fourth Order Transmission Error

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.37-38.623 ◽

2010 ◽

Vol 37-38 ◽

pp. 623-627 ◽

Cited By ~ 1

Author(s):

Jin Zhan Su ◽

Zong De Fang

Keyword(s):

Fourth Order ◽

Gear Tooth ◽

Transmission Error ◽

Circular Arc ◽

Cylindrical Gears ◽

Polynomial Curve ◽

Order Polynomial ◽

Tooth Surfaces ◽

The Stability ◽

Fourth Order Polynomial

A fourth order transmission error was employed to improve the stability and tooth strength of circular-arc curvilinear cylindrical gears. The coefficient of fourth order polynomial curve was determined, the imaginary rack cutter which formed by the rotation of a head cutter and the imaginary pinion were introduced to determine the pinion and gear tooth surfaces, respectively. The numerical simulation of meshing shows: 1) the fourth order transmission error can be achieved by the proposed method; 2) the stability transmission can be performed by increasing the angle of the transfer point of the cycle of meshing; 3) the tooth fillet strength can be enhanced.

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