Use of Fractional-Quadratic Approximation Invariant of Nonlinear Characteristic of Magnetoelectric Sensor

AbstractTethered submerged buoy is used extensively in the field of marine engineering. In this paper considering the effect of wave, the nonlinear dynamics behavior of tethered submerged buoy is debated under wave loadings. According to Newton’s second law, the dynamic of the system is built. The coupling factor of the system is neglected, the natural frequency is calculated. The dynamic responses of the system are analyzed using Runge–Kutta method. Considering the variety of the steepness kA, the phenomenon of dynamic behavior can be periodic, double periodic and quasi-periodic and so on. The bifurcation diagram and the largest Lyapunov exponent are applied to judge the nonlinear characteristic. It is helpful to understand the dynamic behavior of tethered submerged buoy and design the mooring line of tethered submerge buoy.

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A quadratic approximation of the back-off methodology for the control structure selection problem

Computers & Chemical Engineering ◽

10.1016/j.compchemeng.2020.107114 ◽

2020 ◽

Vol 143 ◽

pp. 107114

Author(s):

Christos S. Patilas ◽

Ioannis K. Kookos

Keyword(s):

Control Structure ◽

Quadratic Approximation ◽

Selection Problem ◽

Structure Selection

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Continued fractions with low complexity: transcendence measures and quadratic approximation

Compositio Mathematica ◽

10.1112/s0010437x11007524 ◽

2012 ◽

Vol 148 (3) ◽

pp. 718-750 ◽

Cited By ~ 5

Author(s):

Yann Bugeaud

Keyword(s):

Lower Bound ◽

Continued Fractions ◽

Low Complexity ◽

Quadratic Approximation ◽

Real Numbers ◽

Partial Quotients ◽

Block Complexity

AbstractWe establish measures of non-quadraticity and transcendence measures for real numbers whose sequence of partial quotients has sublinear block complexity. The main new ingredient is an improvement of Liouville’s inequality giving a lower bound for the distance between two distinct quadratic real numbers. Furthermore, we discuss the gap between Mahler’s exponent w2 and Koksma’s exponent w*2.

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Magnetization Research in Time-Domain Magnetic-Circuit Coupled Computation for DC-Biased Transformer

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.347-350.1393 ◽

2013 ◽

Vol 347-350 ◽

pp. 1393-1397

Author(s):

Guo Wei Cai ◽

Yi Gong Wang ◽

Yang Jin Jiang ◽

Tie Feng Li

Keyword(s):

Time Domain ◽

Magnetization Curve ◽

Magnetic Circuit ◽

Coupled Model ◽

Nonlinear Characteristic ◽

Improved Method ◽

Dc Bias ◽

The Time Domain

By revised method of fitting magnetization curve in segment, technique of simulating the nonlinear characteristic of laminated core is enhanced. The DC-bias problem is computed based on the time-domain magnetic-circuit coupled model while considering the saturated and unsaturated magnetizing characteristics of the laminated core. Experiments are designed to verify the validity of the proposed method, and then the volt-ampere feature of unsaturated magnetization is learned. Consequently, the results indicate that the improved method is more accurate and efficient by contrast.

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Low-complexity feed-forward carrier phase estimation for M-ary QAM based on phase search acceleration by quadratic approximation

Optics Express ◽

10.1364/oe.23.019142 ◽

2015 ◽

Vol 23 (15) ◽

pp. 19142 ◽

Cited By ~ 10

Author(s):

Meng Xiang ◽

Songnian Fu ◽

Lei Deng ◽

Ming Tang ◽

Perry Shum ◽

...

Keyword(s):

Carrier Phase ◽

Low Complexity ◽

Quadratic Approximation ◽

Phase Estimation ◽

Feed Forward

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A novel fast Fourier transform accelerated off-grid exhaustive search method for cryo-electron microscopy fitting

Journal of Applied Crystallography ◽

10.1107/s1600576717008172 ◽

2017 ◽

Vol 50 (4) ◽

pp. 1036-1047

Author(s):

Alexandre Hoffmann ◽

Valérie Perrier ◽

Sergei Grudinin

Keyword(s):

Electron Microscopy ◽

Fourier Transform ◽

Fast Fourier Transform ◽

Optimization Technique ◽

Scoring Function ◽

Trust Region ◽

Search Method ◽

Exhaustive Search ◽

Quadratic Approximation ◽

Cryo Electron Microscopy

This paper presents a novel fast Fourier transform (FFT)-based exhaustive search method extended to off-grid translational and rotational degrees of freedom. The method combines the advantages of the FFT-based exhaustive search, which samples all the conformations of a system under study on a grid, with a local optimization technique that guarantees to find the nearest optimal off-grid conformation. The method is demonstrated on a fitting problem and can be readily applied to a docking problem. The algorithm first samples a scoring function on a six-dimensional grid of sizeN6using the FFT. This operation has an asymptotic complexity ofO(N6logN). Then, the method performs the off-grid search using a local quadratic approximation of the cost function and the trust-region optimization algorithm. The computation of the quadratic approximation is also accelerated by FFT at the same additional asymptotic cost ofO(N6logN). The method is demonstrated by fitting atomic protein models into several simulated and experimental maps from cryo-electron microscopy. The method is available at https://team.inria.fr/nano-d/software/offgridfit.

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