检索结果-内蒙古大学图书馆

recursive algorithms for identification of dual Youla-Kucera parametrized plant models in closed loop

EUROPEAN JOURNAL OF CONTROL 2023年 69卷

作者： Landau, Ioan Dore Vau, Bernard Buche, Gabriel Univ Grenoble Alpes Gipsa Lab CNRS Grenoble INP F-38000 Grenoble France IXBLUE 12 Ave Coquelicots F-94385 Bonneuil Sur Marne France

The growing interest in using dual Youla Kucera plant parametrization for modeling plant uncertainties raises the need for recursive identification algorithms dedicated to the identification of these structures in closed loop in view of developing appropriate iterative tuning and adaptive control strategies. The paper presents recursive algorithms for identification in closed loop of dual Youla-Kucera parametrized plant models. These algorithms assure global asymptotic stability in the deterministic environment and allow to obtain unbiased parameter estimation in the presence of measurement noise when the plant model is in the model set. The paper also re-visit the Hansen scheme which allows to associate open loop type recursive identification algorithms for the identification of these structures in closed loop. When the plant model is not in the model set, comparison of the various algorithms is done in terms of the bias distribution. Further comparisons and performance evaluation is provided by simulations on some relevant examples and experimental identification in closed loop of a test bench for active noise control.(c) 2022 European Control Association. Published by Elsevier Ltd. All rights reserved.

关键词： System identification Youla-Kucera parametrization recursive algorithms Identification in closed loop Active noise control

来源：评论

学校读者我要写书评

暂无评论

Emergence of Self-Reproducing Metabolisms as recursive algorithms in an Artificial Chemistry

引用

ARTIFICIAL LIFE 2022年第3-4期27卷 277-299页

作者： Kruszewski, German Mikolov, Tomas Naver Labs Europe Meylan France Czech Inst Informat Robot & Cybernet Prague Czech Republic Czech Tech Univ Prague Czech Republic

One of the main goals of Artificial Life is to research the conditions for the emergence of life, not necessarily as it is, but as it could be. Artificial chemistries are one of the most important tools for this purpose because they provide us with a basic framework to investigate under which conditions metabolisms capable of reproducing themselves, and ultimately, of evolving, can emerge. While there have been successful attempts at producing examples of emergent self-reproducing metabolisms, the set of rules involved remain too complex to shed much light on the underlying principles at work. In this article, we hypothesize that the key property needed for self-reproducing metabolisms to emerge is the existence of an autocatalyzed subset of Turing-complete reactions. We validate this hypothesis with a minimalistic artificial chemistry with conservation laws, which is based on a Turing-complete rewriting system called combinatory logic. Our experiments show that a single run of this chemistry, starting from a tabula rasa state, discovers-with no external intervention-a wide range of emergent structures including ones that self-reproduce in each cycle. All of these structures take the form of recursive algorithms that acquire basic constituents from the environment and decompose them in a process that is remarkably similar to biological metabolisms.

关键词： Artificial chemistry emergence self-reproduction metabolisms recursive algorithms

来源：评论

学校读者我要写书评

暂无评论

The influence of model and measurement uncertainties on damage detection of experimental structures through recursive algorithms

引用

RELIABILITY ENGINEERING & SYSTEM SAFETY 2023年第1期239卷

作者： Ebrahimi, Mehrdad Nobahar, Elnaz Mohammadi, Reza Karami Farsangi, Ehsan Noroozinejad Noori, Mohammad Li, Shaofan KN Toosi Univ Technol Dept Civil Engn Tehran Iran Western Sydney Univ Urban Transformat Res Ctr UTRC Penrith NSW Australia Calif Polytech State Univ San Luis Obispo Dept Mech Engn San Luis Obispo CA USA Univ Leeds Sch Civil Engn Leeds LS2 9JT England Univ Calif Berkeley Dept Civil & Environm Engn Berkeley CA USA

In this work, we developed a framework for identifying frame-type structures regarding the measurement uncertainty and the uncertainty involved in inherent and structural parameters. The identification process is illustrated and examined on a one-eight-scale four-story moment-resisting steel frame under seismic excitation using two well-known recursive schemes: the Extended Kalman filter (EKF) and Unscented Kalman Filter (UKF) methods. The nonlinear system equations were assessed by applying a first-order instantaneous linearization approach through the EKF method. In contrast, the UKF algorithm employs several sample points to estimate moments of random variables' nonlinear transformations. A nonlinear transformation is applied to distribute sample points to derive the precise mean and covariance up to the second order of any nonlinearity. Accordingly, it is theoretically expected that the UKF algorithm is more capable of identifying the nonlinear systems and determining the unknown parameters than the EKF algorithm. The capability of the EKF and UKF algorithms was assessed by considering a 4-story moment-resisting steel frame with several inherent uncertainties, including the material behavior model, boundary conditions, and constraints. In addition to these uncertainties, the combination of acceleration and displacement responses of different structural levels is employed to evaluate the capability of the algorithms. The information entropy measure is used to investigate further the uncertainty of a group of established model parameters. As highlighted, a good agreement is observed between the results using the information entropy measure criterion and those using the UKF and EKF algorithms. The results illustrate that using the responses of fewer levels placed in the proper positions may lead to improved outcomes than those of more improperly positioned levels.

关键词： Uncertainty Extended Kalman filter Unscented Kalman filter recursive algorithms Damage detection Information entropy Sensors

来源：评论

学校读者我要写书评

暂无评论

Screw and Lie group theory in multibody dynamics recursive algorithms and equations of motion of tree-topology systems

引用

MULTIBODY SYSTEM DYNAMICS 2018年第2期42卷 219-248页

作者： Mueller, Andreas Johannes Kepler Univ Linz Inst Robot Altenberger Str 69 A-4040 Linz Austria

Screw and Lie group theory allows for user-friendly modeling of multibody systems (MBS), and at the same they give rise to computationally efficient recursive algorithms. The inherent frame invariance of such formulations allows to use arbitrary reference frames within the kinematics modeling (rather than obeying modeling conventions such as the Denavit-Hartenberg convention) and to avoid introduction of joint frames. The computational efficiency is owed to a representation of twists, accelerations, and wrenches that minimizes the computational effort. This can be directly carried over to dynamics formulations. In this paper, recursive Newton-Euler algorithms are derived for the four most frequently used representations of twists, and their specific features are discussed. These formulations are related to the corresponding algorithms that were presented in the literature. Two forms of MBS motion equations are derived in closed form using the Lie group formulation: the so-called Euler-Jourdain or "projection" equations, of which Kane's equations are a special case, and the Lagrange equations. The recursive kinematics formulations are readily extended to higher orders in order to compute derivatives of the motions equations. To this end, recursive formulations for the acceleration and jerk are derived. It is briefly discussed how this can be employed for derivation of the linearized motion equations and their time derivatives. The geometric modeling allows for direct application of Lie group integration methods, which is briefly discussed.

关键词： Multibody system dynamics Relative coordinates recursive algorithms O(n) Screws Lie groups Newton-Euler equations Lagrange equations Kane's equations Euler-Jourdain equations Projection equations Lie group integration Linearization

来源：评论

学校读者我要写书评

暂无评论

Analysis of Evaluation Model of Multimedia Teaching Course Reform Model Based on Structural recursive algorithms

Analysis of Evaluation Model of Multimedia Teaching Course R...

引用

作者： Cao Wensheng Guizhou Vocational Technology College of Electronics & Information

With the development of network technology, the reform of multimedia network teaching curriculum is accelerating, which promotes the reform of college teaching mode. At the same time, the existing multimedia teaching methods still have some problems, leading to the teaching effect can not be effectively improved. Therefore, on the basis of exploring the problems faced by multimedia teaching curriculum reform, this paper evaluates the new model based on structural recursive algorithm. The evaluation results show that this algorithm can effectively promote the reform process of multimedia teaching curriculum and help to improve the teaching effect.

关键词： recursive algorithms Multimedia teaching Curriculum reform Model Evaluation

来源：评论

学校读者我要写书评

暂无评论

Laguerre based predictors in discrete-time recursive algorithms: A solution for open-loop identification under oversampling

引用

IFAC-PapersOnLine 2017年第1期50卷 12911-12918页

作者： Vau, Bernard Bourlès, Henri SATIE Ecole normale supérieure de Cachan Cachan94230 France

In this paper we propose a novel formulation of the predictor used in open-loop recursive identification algorithms. The predicted output is expressed by means of an orthogonal Laguerre transfer functions basis. This predictor representation presents many advantages: It makes it possible to identify robustly oversampled systems without any bias in low frequency, and to obtain relevant reduced order models. The Laguerre pole plays the role of a tuning parameter enabling the selection of the best approximation frequency area. The proposed schemes address both output error and ARMAX systems. Simulation and experimental results show all the practical benefits provided by these algorithms. © 2017

关键词： Transfer functions Orthogonal functions Adaptive Control ARMAX model Identification algorithms Laguerre Output error models recursive algorithms recursive estimation

来源：评论

学校读者我要写书评

暂无评论

Laguerre based predictors in discrete-time recursive algorithms: A solution for open-loop identification under oversampling

Laguerre based predictors in discrete-time recursive algorit...

引用

20th World Congress of the International-Federation-of-Automatic-Control (IFAC)

作者： Vau, Bernard Bourles, Henri SATIE Ecole Normale Super Cachan F-94230 Cachan France

In this paper we propose a novel formulation of the predictor used in open-loop recursive identification algorithms The predicted output is expressed by means of an orthogonal Laguerre transfer functions basis. This predictor representation presents many advantages: It makes it possible to identify robustly oversampled systems without any bias in low frequency, and to obtain relevant reduced order models. The Laguerre pole plays the role of a tuning parameter enabling the selection of the best approximation frequency area. The proposed schemes address both output error and ARMAX systems. Simulation and experimental results show all the practical benefits provided by these algorithms (C) 2017, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.

关键词： Identification algorithms recursive algorithms recursive estimation output error model identification ARMAX model identification Laguerre transfer functions adaptive control

来源：评论

学校读者我要写书评

暂无评论

recursive algorithms FOR DISTRIBUTED FORESTS OF OCTREES

引用

SIAM JOURNAL ON SCIENTIFIC COMPUTING 2015年第5期37卷 C497-C531页

作者： Isaac, Tobin Burstedde, Carsten Wilcox, Lucas C. Ghattas, Omar Univ Texas Austin Inst Computat Engn & Sci Austin TX 78712 USA Univ Bonn Inst Numer Simulat D-53115 Bonn Germany Naval Postgrad Sch Dept Appl Math Monterrey CA 93943 USA Univ Texas Austin Dept Mech Engn Jackson Sch Geosci Austin TX 78712 USA Univ Texas Austin Inst Computat Engn & Sci Austin TX 78712 USA

The forest-of-octrees approach to parallel adaptive mesh refinement and coarsening has recently been demonstrated in the context of a number of large-scale PDE-based applications. Efficient reference software has been made freely available to the public both in the form of the standalone p4est library and more indirectly by the general-purpose finite element library deal. II, which has been equipped with a p4est backend. Although linear octrees, which store only leaf octants, have an underlying tree structure by definition, it is not fully exploited in previously published mesh-related algorithms. This is because tree branches are not explicitly stored and because the topological relationships in meshes, such as the adjacency between cells, introduce dependencies that do not respect the octree hierarchy. In this work, we combine hierarchical and topological relationships between octants to design efficient recursive algorithms that operate on distributed forests of octrees. We present three important algorithms with recursive implementations. The first is a parallel search for leaves matching any of a set of multiple search criteria, such as leaves that contain points or intersect polytopes. The second is a ghost layer construction algorithm that handles arbitrarily refined octrees that are not covered by previous algorithms, which require a 2: 1 condition between neighboring leaves. The third is a universal mesh topology iterator. This iterator visits every cell in a partition, as well as every interface (face, edge, and corner) between these cells. The iterator calculates the local topological information for every interface that it visits, taking into account the nonconforming interfaces that increase the complexity of describing the local topology. To demonstrate the utility of the topology iterator, we use it to compute the numbering and encoding of higher-order C-0 nodal basis functions used for finite elements. We analyze the complexity of the new recursive a

关键词： forest of octrees parallel adaptive mesh refinement Morton code recursive algorithms large-scale scientific computing

来源：评论

学校读者我要写书评

暂无评论

Acoustic multiple scattering using recursive algorithms

引用

JOURNAL OF COMPUTATIONAL PHYSICS 2015年 299卷 787-803页

作者： Amirkulova, Feruza A. Norris, Andrew N. Rutgers State Univ Mech & Aerosp Engn Piscataway NJ 08854 USA

Acoustic multiple scattering by a cluster of cylinders in an acoustic medium is considered. A fast recursive technique is described which takes advantage of the multilevel Block Toeplitz structure of the linear system. A parallelization technique is described that enables efficient application of the proposed recursive algorithm for solving multilevel Block Toeplitz systems on high performance computer clusters. Numerical comparisons of CPU time and total elapsed time taken to solve the linear system using the direct LAPACK and TOEPLITZ libraries on Intel FORTRAN, show the advantage of the TOEPLITZ solver. Computations are optimized by multi-threading which displays improved efficiency of the TOEPLITZ solver with the increase of the number of scatterers and frequency. (C) 2015 Elsevier Inc. All rights reserved.

关键词： Acoustics Multiple scattering Wave propagation recursive algorithms Computation methods Parallel computation OpenMP

来源：评论

学校读者我要写书评

暂无评论

Exchangeability, Prediction and Predictive Modeling in Bayesian Statistics

引用

STATISTICAL SCIENCE 2025年第1期40卷 40-67页

作者： Fortini, Sandra Petrone, Sonia Bocconi Univ Dept Decis Sci Stat Milan Italy Bocconi Univ Dept Decis Sci Stat Milan Italy Bocconi Univ Bocconi Inst Data Sci & Analyt Milan Italy

There is currently a renewed interest in the Bayesian predictive approach to statistics. This paper offers a review on foundational concepts and focuses on "predictive modeling," which by directly reasoning on prediction bypasses inferential models or may characterize them. We detail predictive characterizations in exchangeable and partially exchangeable settings, for a large variety of data structures, and hint at new directions. The underlying concept is that Bayesian predictive rules are probabilistic learning rules, formalizing through conditional probability how we learn on future events given the available information. This concept has implications in any statistical problem and in inference, from classic contexts to less explored challenges, such as providing Bayesian uncertainty quantification to predictive algorithms in data science, as we show in the last part of the paper. The paper not only gives a historical overview but also includes a few new results, presents some recent developments and poses some open questions.

关键词： Bayesian foundations predictive characteriza- tions Bayesian nonparametrics predictive sufficiency partial exchangeability recursive algorithms

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：