1,592 research outputs found
Recent Advances and Applications of Fractional-Order Neural Networks
This paper focuses on the growth, development, and future of various forms of fractional-order neural networks. Multiple advances in structure, learning algorithms, and methods have been critically investigated and summarized. This also includes the recent trends in the dynamics of various fractional-order neural networks. The multiple forms of fractional-order neural networks considered in this study are Hopfield, cellular, memristive, complex, and quaternion-valued based networks. Further, the application of fractional-order neural networks in various computational fields such as system identification, control, optimization, and stability have been critically analyzed and discussed
Group and phase velocities in the free-surface visco-potential flow: new kind of boundary layer induced instability
Water wave propagation can be attenuated by various physical mechanisms. One
of the main sources of wave energy dissipation lies in boundary layers. The
present work is entirely devoted to thorough analysis of the dispersion
relation of the novel visco-potential formulation. Namely, in this study we
relax all assumptions of the weak dependence of the wave frequency on time. As
a result, we have to deal with complex integro-differential equations that
describe transient behaviour of the phase and group velocities. Using numerical
computations, we show several snapshots of these important quantities at
different times as functions of the wave number. Good qualitative agreement
with previous study [Dutykh2009] is obtained. Thus, we validate in some sense
approximations made anteriorly. There is an unexpected conclusion of this
study. According to our computations, the bottom boundary layer creates
disintegrating modes in the group velocity. In the same time, the imaginary
part of the phase velocity remains negative for all times. This result can be
interpreted as a new kind of instability which is induced by the bottom
boundary layer effect.Comment: 12 pages, 7 figures. Reviewer's comments were taken into account.
Other author's papers can be downloaded at
http://www.lama.univ-savoie.fr/~dutykh
Particle swarm optimization with fractional-order velocity
This paper proposes a novel method for controlling the convergence rate of a particle swarm optimization algorithm using fractional calculus (FC) concepts. The optimization is tested for several well-known functions and the relationship between the fractional order velocity and the convergence of the algorithm is observed. The FC demonstrates a potential for interpreting evolution of the algorithm and to control its convergence
Complex order van der Pol oscillator
In this paper a complex-order van der Pol oscillator is considered. The complex derivative Dα±ȷβ , with α,β∈R + is a generalization of the concept of integer derivative, where α=1, β=0. By applying the concept of complex derivative, we obtain a high-dimensional parameter space. Amplitude and period values of the periodic solutions of the two versions of the complex-order van der Pol oscillator are studied for variation of these parameters. Fourier transforms of the periodic solutions of the two oscillators are also analyzed
Recent Advances in Theoretical and Computational Modeling of Composite Materials and Structures
The advancement in manufacturing technology and scientific research has improved the development of enhanced composite materials with tailored properties depending on their design requirements in many engineering fields, as well as in thermal and energy management. Some representative examples of advanced materials in many smart applications and complex structures rely on laminated composites, functionally graded materials (FGMs), and carbon-based constituents, primarily carbon nanotubes (CNTs), and graphene sheets or nanoplatelets, because of their remarkable mechanical properties, electrical conductivity and high permeability. For such materials, experimental tests usually require a large economical effort because of the complex nature of each constituent, together with many environmental, geometrical and or mechanical uncertainties of non-conventional specimens. At the same time, the theoretical and/or computational approaches represent a valid alternative for designing complex manufacts with more flexibility. In such a context, the development of advanced theoretical and computational models for composite materials and structures is a subject of active research, as explored here for a large variety of structural members, involving the static, dynamic, buckling, and damage/fracturing problems at different scales
Application of fractional algorithms in control of a quad rotor flight
This paper studies the application of fractional algorithms in the control of a quad-rotor rotorcraft machine. The main contribution of this paper focuses in the development a flight simulator to provide the evaluation model of the quad-rotor. Several basic maneuvers are investigated, namely the elevation and the position control.N/
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