If the labeling values of edges and vertexs for a graph G(p, q) are mapped to 1, 2, , p+q, and the sum of the labels of any two vertexs and their associated edges is equal to a constant, this labeling is called edge-m...
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This study proposes a new approach for the optimization of phase and magnitude responses of fractional-order capacitive and inductive elements based on the mixed integer-order genetic algorithm (GA), over a bandwidth ...
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This study proposes a new approach for the optimization of phase and magnitude responses of fractional-order capacitive and inductive elements based on the mixed integer-order genetic algorithm (GA), over a bandwidth of four-decade, and operating up to 1 GHz with a low phase error of approximately +/- 1 degrees. It provides a phase optimization in the desired bandwidth with minimal branch number and avoids the use of negative component values, and any complex mathematical analysis. Standardized, IEC 60063 compliant commercially available passive component values are used;hence, no correction on passive elements is required. To the best knowledge of the authors, this approach is proposed for the first time in the literature. As validation, we present numerical simulations using MATLAB (R) and experimental measurement results, in particular, the Foster-II and Valsa structures with five branches for precise and/or high-frequency applications. Indeed, the results demonstrate excellent performance and significant improvements over the Oustaloup approximation, the Valsa recursive algorithm, and the continued fraction expansion and the adaptability of the GA-based design with five different types of distributed RC/RL network.
In real applications, a time delay in the parameter update of the neural network is sometimes required. In this paper, motivated by the Chebyshev functional link artificial neural network (CFLANN), a new structure bas...
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In real applications, a time delay in the parameter update of the neural network is sometimes required. In this paper, motivated by the Chebyshev functional link artificial neural network (CFLANN), a new structure based on the time delay adaptation is developed for nonlinear system identification. Particularly, we present a new CFLANN-delayed recursive least square (CFLANN-DRLS), as an online learning algorithm for parameter adaptation in CFLANN. The CFLANN-DRLS algorithm exploits the time delayed error signal with the gain vector delayed by D cycles to form the weight increment term, which provides potential implementation in the filter with pipelined structure. However, it suffers from the instability problems under imperfect network delay estimate. To overcome this problem, we further propose a modified CFLANN-DRLS (CFLANN-MDRLS) algorithm by including a compensation term to the error signal. We analyze the stability and convergence of the proposed algorithm. Simulations in nonlinear system identification contexts reveal that the newly proposed CFLANN-MDRLS algorithm can effectively compensate the time delay of system and it is even superior to the algorithm without delay in some cases. (C) 2018 Elsevier B.V. All rights reserved.
Big multi-step wind speed forecasting is hard to be realized due to the high-requirement of the built forecasting models. However, the big multi-step forecasting is expected in the wind power systems, which can provid...
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Big multi-step wind speed forecasting is hard to be realized due to the high-requirement of the built forecasting models. However, the big multi-step forecasting is expected in the wind power systems, which can provide sufficient time for the wind grids to be operated in the emergency cases. In the study, a new hybrid computational framework for the big multi-step wind speed forecasting is proposed, consisting of Wavelet Packet Decomposition (WPD), Elman Neural Networks (ENN), boosting algorithms and Wavelet Packet Filter (WPF). The novelty of the study is to investigate the big multi-step wind speed forecasting performance using various computing strategies in the proposed new hybrid WPD-BoostENN-WPF framework. Four different wind speed time series data are provided to complete the real forecasting experiments. The experimental results indicate that: (a) all of the proposed hybrid models have better performance than the corresponding single forecasting models in the big multi-step predictions. The 9 step MAE errors for the experimental data #1 from the proposed four hybrid forecasting models are only 1.2821 m/s, 1.1276 m/s, 1.1718 m/s and 1.2684 m/s, respectively;(b) the proposed four hybrid forecasting models have no significant forecasting difference;and (c) all of them are suitable for the big multi-step wind speed forecasting. (C) 2018 Elsevier Ltd. All rights reserved.
The enumeration of all minimal paths between a terminal pair of a given graph is widely used in a lot of applications such as network reliability assessment. In this paper, we present a new and efficient algorithm to ...
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The enumeration of all minimal paths between a terminal pair of a given graph is widely used in a lot of applications such as network reliability assessment. In this paper, we present a new and efficient algorithm to generate all minimal paths in a graph G(V, E). The algorithm proposed builds the set of minimal paths gradually, starting from the source node s. We present two versions of our algorithm;the first version determines all feasible paths between a pair of terminals in a directed graph without cycle, and this version runs in linear time O(vertical bar V vertical bar + vertical bar E vertical bar). The second version determines all minimal paths in a general graph (directed and undirected graph). In order to show the process and the effectiveness of our method, an illustrative example is presented for each case.
作者：
Flammang, VUniv Lorraine
Dept Math UMR CNRS IECL 7502 UFR MIM Site Metz3 Rue Augustin FresnelBP 45112 F-57073 Metz 03 France
Thanks to our recursive algorithm developed in [Trace of totally positive algebraic integers and integer transfinite diameter, Math. Comp. 78(266) (2009) 1119-1125], we prove that, if a is a totally positive algebraic...
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Thanks to our recursive algorithm developed in [Trace of totally positive algebraic integers and integer transfinite diameter, Math. Comp. 78(266) (2009) 1119-1125], we prove that, if a is a totally positive algebraic integer of degree d >= 2 with minimum conjugate a l then, with a finite number of explicit exceptions, tr(alpha)/d >=alpha(1) + 1.68.
作者：
Flammang, VUniv Lorraine
UMR CNRS 7502 IECL Dept MathUFR MIM Site Metz3 Rue Augustin FresnelBP 45112 F-57073 Metz 03 France
We consider intervals of the form [r/s, u], where r, s are positive integers with gcd (r, s) = 1 and u is a real number, or of the form [0, (root a - root b)(2)], where a, b are positive integers. Thanks to a lemma of...
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We consider intervals of the form [r/s, u], where r, s are positive integers with gcd (r, s) = 1 and u is a real number, or of the form [0, (root a - root b)(2)], where a, b are positive integers. Thanks to a lemma of Chudnovsky, we give first a lower bound of the integer trans finite diameter of such intervals. Then, using the method of explicit auxiliary functions and our recursive algorithm, we explain how to get an upper bound for this quantity. We finish with some numerical examples. Secondly, we prove inequalities on the integer trans finite diameter of Farey intervals, i.e., intervals of the type [a/q, b/s], where vertical bar as - bq vertical bar = 1.
The direct problem of light scattering for a fiber optic Bragg grating is considered. The formulation and solution of the problem based on the transfer-matrix method are discussed. A modification of the method is prop...
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The direct problem of light scattering for a fiber optic Bragg grating is considered. The formulation and solution of the problem based on the transfer-matrix method are discussed. A modification of the method is proposed which reduces it to a computationally convenient universal recursive algorithm similar to the Thomas algorithm. Using the finite volume method in the coupled-mode approximation, the elements of transfer matrices were calculated with local third-order accuracy in coordinate on a nonuniform computational grid. Numerical calculations for the direct scattering problem for a Bragg grating with apodization and nonlinear chirp were performed using the recursive algorithm. Numerical simulations confirmed the significant increase in the accuracy of calculations when solving the scattering problem on a nonuniform grid.
A scattering (S-) parameter method has been proposed for electromagnetic property extraction of a target layer within metal-backed inhomogeneous metamaterial (MM) structures. It relies on recursive S-parameters for tw...
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A scattering (S-) parameter method has been proposed for electromagnetic property extraction of a target layer within metal-backed inhomogeneous metamaterial (MM) structures. It relies on recursive S-parameters for two different polarizations (parallel and perpendicular). Two different algorithms depending on the value of the incidence angles were proposed to add flexibility to our method. The algorithms were first validated by a metal-backed quasi-one-port method applicable only for one-layer (homogeneous) samples. Then, they were applied to extract electromagnetic properties of the split-ring-resonator-wire MM slab of a metal-backed two-layer inhomogeneous structure and the Omega MM slab of a metal-backed four-layer inhomogeneous structure, and extracted properties by our algorithms were compared with those retrieved by different methods applicable for homogeneous samples only. The accuracy of our method was also examined when there was some noise in S-parameters, when there was a misalignment in incidence angles, and a when large value of iteration number was used.
作者：
Flammang, VUniv Lorraine
IECL Site Metz UFR MIMDept Math 3 Rue Augustin FresnelBP 45112 F-57073 Metz 3 France
We give upper and lower bounds for the trace of a Salem number whose Mahler measure is less than 1.3. We use the method of explicit auxiliary functions, combined with a recursive algorithm developed by the author.
We give upper and lower bounds for the trace of a Salem number whose Mahler measure is less than 1.3. We use the method of explicit auxiliary functions, combined with a recursive algorithm developed by the author.
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