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Evolvability Metric Estimation by a Parallel Perceptron for On-Line Selection Hyper-Heuristics

IEEE ACCESS 2017年 5卷 7055-7063页

作者： Soria-Alcaraz, Jorge A. Espinal, Andres Sotelo-Figueroa, Marco A. Univ Guanajuato Dept Estudios Org Div Ciencias Econ Adm Guanajuato 36000 Mexico

Online hyper-heuristic selection is a novel and powerful approach to solving complex problems. This approach dynamically selects, based on the state of a given solution, the most promising operator (from a pool of operators) to continue the search process. The dynamic selection is usually based on the analysis of the latest applications of a given operator during actual execution, estimating the potential success of the operator at the current solution state. The estimation can be made by evolvability metrics. Calculating an evolvability metric is computationally expensive since it requires the generation and evaluation of a neighborhood of solutions. This paper aims to estimate the potential success of an operator for a given solution state by using a pre-trained neural network;known as a parallel perceptron. The proposal accelerates the online selection process, allowing us to achieve better performance than hyper-heuristic models, which directly use evolvability functions.

关键词： adaptive algorithm optimization artificial intelligence artificial neural networks parallel perceptron

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adaptive multistep time discretization and linearization based on a posteriori error estimates for the Richards equation

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APPLIED NUMERICAL MATHEMATICS 2017年 112卷 104-125页

作者： Baron, V. Coudiere, Y. Sochala, P. DUSA Ave Michel Serres F-47000 Agen France IMB 351 Cours Liberat F-33400 Talence France Bur Rech Geol & Minieres 3 Ave Claude Guillemin F-45060 Orleans France

We derive some a posteriori error estimates for the Richards equation. This parabolic equation is nonlinear in space and in time, thus its resolution requires fixed-point iterations within each time step. We measure the approximation error with the dual norm of the residual. A computable upper bound of this error consists of several estimators involving adequate reconstructions based on the degrees of freedom of the scheme. The space and time reconstructions are specified for a two-step backward differentiation formula and a discrete duality finite volume scheme. Our strategy to decrease the computational cost relies on an aggregation of the estimators in three components: space discretization, time discretization, and linearization. We propose an algorithm to stop the fixed-point iterations after the linearization error becomes negligible, and to choose the time step in order to balance the time and space errors. We analyze the influence of the parameters of this algorithm on three test cases and quantify the gain obtained in comparison with a classical simulation. (C) 2016 IMACS. Published by Elsevier B.V. All rights reserved.

关键词： A posteriori error estimates Richards equation Discrete duality finite volume scheme Backward differentiation formula adaptive algorithm

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H_∞ optimality and a posteriori output estimate of the forgetting factor NLMS algorithm

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AUTOMATICA 2017年 75卷 244-248页

作者： Nishiyama, Kiyoshi Iwate Univ Fac Sci & Engn Dept Syst Innovat Engn 4-3-5 Ueda Morioka Iwate Japan

The normalized least mean squares (NLMS) algorithm is widely used for adaptive filtering. The NLMS algorithm may be extended using a variety of weight parameters that improve its performance. One such extension involves appropriately introducing a forgetting factor into the NLMS algorithm using the H-infinity framework. The resultant forgetting factor NLMS (FFNLMS) algorithm may be regarded as a special case of the improved proportionate NLMS (IPNLMS) algorithm. This work reveals that the FFNLMS algorithm is H-infinity-optimaL and the a posteriori output estimate is identical to the observation signal for sufficiently large times. (C) 2016 Elsevier Ltd. All rights reserved.

关键词： adaptive filters adaptive algorithm Forgetting factor NLMS algorithm H-infinity filter

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VARIATIONAL FORMULATION AND NUMERICAL ANALYSIS OF LINEAR ELLIPTIC EQUATIONS IN NONDIVERGENCE FORM WITH CORDES COEFFICIENTS

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SIAM JOURNAL ON NUMERICAL ANALYSIS 2017年第2期55卷 737-757页

作者： Gallistl, Dietmar Karlsruher Inst Technol Inst Angew & Numer Math D-76131 Karlsruhe Germany

This paper studies formulations of second-order elliptic partial differential equations in nondivergence form on convex domains as equivalent variational problems. The first formulation is that of Smears and Suli [SIAM J. Numer. Anal., 51 ( 2013), pp. 2088-2106], and the second one is a new symmetric formulation based on a least-squares functional. These formulations enable the use of standard finite element techniques for variational problems in subspaces of II2 as well as mixed finite element methods from the context of fluid computations. Besides the immediate quasi-optimal a priori error bounds, the variational setting allows for a posteriori error control with explicit constants and adaptive mesh-refinement. The convergence of an adaptive algorithm is proved. Numerical results on uniform and adaptive meshes are included.

关键词： finite element methods Cordes coefficients nondivergence form fourth order variational formulation adaptive algorithm

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Two Approaches to Speed Control for Multi-Mass System With Variable Mechanical Parameters

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IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS 2017年第4期64卷 3338-3347页

作者： Brock, Stefan Luczak, Dominik Nowopolski, Krzysztof Pajchrowski, Tomasz Zawirski, Krzysztof Poznan Univ Tech Inst Control & Informat Engn PL-60965 Poznan Poland

This paper is dedicated to the motion control system of a multimass mechanism with occurring resonances and variable moment of inertia. The proposed concept of control structure for such mechanism consists of a filter damping higher resonance frequencies and an adaptive speed controller. The filter has properly selected fixed characteristics giving a compromised filtering effect in a range of resonance frequency variation, caused by the variable moment of inertia. The used neural adaptive controller realizes active damping of lower resonance frequencies, which are not eliminated by the resonance filter. This original concept is compared with a more complex solution, treated as a reference, which contains an offline-tuned resonance filter together with an offline-adjusted PI-two degrees of freedom controller. Good speed control dynamic properties of the proposed concept in comparison with the reference complex solution are proven by laboratory results.

关键词： adaptive algorithm digital filters discrete Fourier transforms (DFTs) frequency response motion control neurocontrollers PI control robust control velocity control vibration control

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adaptive smoothing algorithms for nonsmooth composite convex minimization

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COMPUTATIONAL OPTIMIZATION AND APPLICATIONS 2017年第3期66卷 425-451页

作者： Quoc Tran-Dinh Univ N Carolina Dept Stat & Operat Res Chapel Hill NC 27599 USA

We propose an adaptive smoothing algorithm based on Nesterov's smoothing technique in Nesterov (Math Prog 103(1):127-152, 2005) for solving "fully" nonsmooth composite convex optimization problems. Our method combines both Nesterov's accelerated proximal gradient scheme and a new homotopy strategy for smoothness parameter. By an appropriate choice of smoothing functions, we develop a new algorithm that has the -worst-case iteration-complexity while preserves the same complexity-per-iteration as in Nesterov's method and allows one to automatically update the smoothness parameter at each iteration. Then, we customize our algorithm to solve four special cases that cover various applications. We also specify our algorithm to solve constrained convex optimization problems and show its convergence guarantee on a primal sequence of iterates. We demonstrate our algorithm through three numerical examples and compare it with other related algorithms.

关键词： Nesterov's smoothing technique Accelerated proximal-gradient method adaptive algorithm Composite convex minimization Nonsmooth convex optimization

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AN adaptive VIDEO DIGITAL STEGANOGRAPHY algorithm

AN ADAPTIVE VIDEO DIGITAL STEGANOGRAPHY ALGORITHM

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2017 2nd Joint International Mechanical,Electronic and Information Technology Conference(JIMET 2017)

作者： Guangqi Liu Lianhai Wang Shuhui Zhang Shumian Yang Qiuxiang Guo Shandong Computer Science Center (National Supercomputer Center in Jinan) Shandong Provincial Key Laboratory of Computer Networks

In this paper, we propose an adaptive video digital steganography algorithm, it mainly includes information steganography and information extraction of two parts. Information steganography is mainly includes three steps, first to split video file into the I frame, B&P frame. Second we divide B&P frame into 16 × 16 block, choose the big macro block of motion vector as secret information embedding location, at the same time divide I frame into 8×8 block, select the texture region as the location of the control information steganography. Third, embed secret information in B&P frame, embed control information in I frame. The control information is occurring in the process of secret information embedding position information and number of embeded frame, etc. Extract part of the algorithm, first split the video file into I frame, B&P frame. Then, we divide I frame into 8×8 block and extract the control information in the texture region. Third, we extract the secret information in the B&P frame by the corresponding position embedding algorithm and control information. The algorithm is effective to solve the problems of greater influence on the quality and small embedded capacity. The algorithm not only has strong adaptability, but also can greatly improve the security of the system.

关键词： Digital steganography adaptive algorithm System Security

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Multiple-Reflection Noise Attenuation Using adaptive Randomized-Order Empirical Mode Decomposition

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IEEE GEOSCIENCE AND REMOTE SENSING LETTERS 2017年第1期14卷 18-22页

作者： Chen, Wei Xie, Jianyong Zu, Shaohuan Gan, Shuwei Chen, Yangkang Yangtze Univ Minist Educ Key Lab Explorat Technol Oil & Gas Resources Wuhan 430100 Peoples R China Hubei Cooperat Innovat Ctr Unconvent Oil & Gas Wuhan 430100 Peoples R China China Univ Petr State Key Lab Petr Resources & Prospecting Beijing 102200 Peoples R China Univ Alberta Dept Phys Edmonton AB T6G 2E1 Canada Univ Texas Austin Jackson Sch Geosci Austin TX 78713 USA Oak Ridge Natl Lab Oak Ridge TN 37830 USA

We propose a novel approach for removing noise from multiple reflections based on an adaptive randomized-order empirical mode decomposition (EMD) framework. We first flatten the primary reflections in common midpoint gather using the automatically picked normal moveout velocities that correspond to the primary reflections and then randomly permutate all the traces. Next, we remove the spatially distributed random spikes that correspond to the multiple reflections using the EMD-based smoothing approach that is implemented in the f-x domain. The trace randomization approach can make the spatially coherent multiple reflections random along the space direction and can decrease the coherency of near-offset multiple reflections. The EMD-based smoothing method is superior to median filter and prediction error filter in that it can help preserve the flattened signals better, without the need of exact flattening, and can preserve the amplitude variation much better. In addition, EMD is a fully adaptive algorithm and the parameterization for EMD-based smoothing can be very convenient.

关键词： adaptive algorithm empirical mode decomposition (EMD) multiple reflections noise attenuation randomized-order EMD

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adaptive stabilized finite volume method and convergence analysis for the Oseen equations

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BOUNDARY VALUE PROBLEMS 2018年第1期2018卷 1页

作者： Lu, Junxiang Zhang, Tong Xian Polytech Univ Sch Sci Xian Shaanxi Peoples R China Henan Polytech Univ Sch Math & Informat Sci Jiaozuo Peoples R China

In this paper, based on the pressure project method, we consider an adaptive stabilized finite volume method for the Oseen equations with the lowest equal order finite element pair. Firstly, we develop the discrete forms in both finite element and finite volume methods, and establish the existence and uniqueness of numerical solutions by establishing the equivalence of linear terms in finite element and finite volume methods. Secondly, a residual type a posteriori error estimator is designed, and the computable global upper and local lower bounds between the exact solutions and the finite volume solutions are established. Thirdly, a discrete local lower bound between two successive finite volume solutions is obtained, convergence analysis of the adaptive stabilized finite volume method is also performed. Finally, some numerical results are presented to verify the performances of the developed error estimators and confirm the established theoretical findings.

关键词： adaptive algorithm Stabilized finite volume method Oseen equations Convergence

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adaptive algorithm in the Application of Visual Measurement System

Adaptive Algorithm in the Application of Visual Measurement ...

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2012 Conference on Modelling, Identification and Control (MIC2012)

作者： Jing Zhou ShiJun Li DongYan Huang Hong Wang YeChi Zhang Wei Wang College of Information Technology Jilin Agricultural University Electronic Commerce Department China United Network Communication Co.LTD.of Changchun City Branch Department of Public Customer China Telecom Corporation Limited Jilin Branch Special Market Sales Center China Telecom Corporation Limited Changchun Branch

ISBN: (纸本)9781627483766

Focus on the problem that noise is existing in the input signals and output signals of visual measurement system,if calculate via the classic least mean square algorithm or recursive least square,it would generate the larger errors;Or calculate directly,the calculation work loading is too *** the solution of weight vector could be as the limited best optimization solution of Rayleigh Quotient of augmentation input vector self correlation matrix,take iteration estimation to the augmentation input vector and set up the function relationship between step factor and error;The simulation analysis experiment results indicate the standard tolerance of proposed adaptive total least squares algorithm is0.0375mm;but the one of normal total least squares algorithm is only 0.0598 ***,the proposed algorithm has more high precision than normal total least squares algorithm,and its structure is simple,the calculation speed is faster.

关键词： adaptive algorithm Visual Measurement Total Least Squares

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