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Modeling of complex-valued Wiener systems using B-spline neural network
No full textIn this brief, a new complex-valued B-spline neural network is introduced in order to model the complex-valued Wiener system using observational input/output data. The complex-valued nonlinear static function in the Wiener system is represented using the tensor product from two univariate B-spline neural networks, using the real and imaginary parts of the system input. Following the use of a simple least squares parameter initialization scheme, the Gauss-Newton algorithm is applied for the parameter estimation, which incorporates the De Boor algorithm, including both the B-spline curve and the first-order derivatives recursion. Numerical examples, including a nonlinear high-power amplifier model in communication systems, are used to demonstrate the efficacy of the proposed approaches
Wiener-Hopf solution for impenetrable wedges at skew incidence
No full textA new Wiener-Hopf approach for the solution of impenetrable wedges at skew incidence is presented. Mathematical aspects are described in a unified and consistent theory for angular region problems. Solutions are obtained using analytical and numerical-analytical approaches. Several numerical tests from the scientific literature validate the new technique, and new solutions for anisotropic surface impedance wedges are solved at skew incidence. The solutions are presented considering the geometrical and uniform theory of diffraction coefficients, total fields, and possible surface wave contribution
A note on the factorization of matrices occurring in Wiener-Hopf problems
No full textSimple expressions for the Wiener-Hopf factors of a certain matrix considered by Daniele are given
Wiener modelling and model predictive control for wastewater applications
No full textThe research presented in this paper aims to demonstrate the application of predictive control to an integrated wastewater system with the use of the wiener modeling approach. This allows the controlled process, dissolved oxygen, to be considered to be composed of two parts: the linear dynamics, and a static nonlinearity, thus allowing control other than common approaches such as gain-scheduling, or switching, for series of linear controllers. The paper discusses various approaches to the modelling required for control purposes, and the use of wiener modelling for the specific application of integrated waste water control. This paper demonstrates this application and compares with that of another nonlinear approach, fuzzy gain-scheduled control
The method of finite-product extraction and an application to Wiener-Hopf theory
No full textCopyright @ The Author, 2011. The publisher version of the article can be accessed at the link below.In this work we describe a simple method for finding approximate representations for special functions which are entire transcendental functions that can be represented by infinite products. This method replaces the infinite product by a finite polynomial and Gamma functions. This approximate representation is shown in the case of Bessel functions to be very accurate over a large range of parameter values. These approximate expressions can be useful for finding the roots of a transcendental equation and the Wiener-Hopf factorization of functions involving such Bessel functions.The method is shown to be potentially useful for other transcendental andWiener-Hopf problems, which involve other entire functions that have infinite product representations
A cyclo-stationary complex multichannel wiener filter for the prediction of wind speed and direction
No full textThis paper develops a linear predictor for application to wind speed and direction forecasting in time and across different sites. The wind speed and direction are modelled via the magnitude and phase of a complex-valued time-series. A multichannel adaptive filter is set to predict this signal, based on its past values and the spatio-temporal correlation between wind signals measured at numerous geographical locations. The time-varying nature of the underlying system and the annual cycle of seasons motivates the development of a cyclo-stationary Wiener filter, which is tested on hourly mean wind speed and direction data from 13 weather stations across the UK, and shown to provide an improvement over both stationary Wiener filtering and a recent auto-regressive approach
Geschichte der Wiener Gemäldesammlungen /
No full textNo more published; originally projected as a work in 2 v., of which only chapters 1/2-4 of v.1 are published seperately, v.1, chapters 1/2 being called "Erster Halbband." The author resumed publication in 1913 under title: Lexicon der Wiener Gemäldesammlungen, (v.1), published by G. MHüller, being the "Abschlussbände" of his Geschichte der Wiener Gemäldesammlungen, which also is no more published.Includes bibliographical references and indexes.1. Bd., 1. Halbbd. Einleitung und Geschichte der Kaiserlichen Gemäldegalerie -- 1. Bd., 3. Capitel. Privatgalerien des XVIII. Jahrhunderts -- [1. Bd.] 4. Capitel. Die Galerie in der Akademie der Bildenden Künste.Mode of access: Internet
Skew Incidence on Concave Wedge With Anisotropic Surface Impedance
No full textThe diffraction of a plane wave at skew incidence by an arbitrary-angled concave wedge with anisotropic impedance faces is studied. Concave wedges are of interest in wireless propagation models, in particular on modeling buildings and reflectors. The solution is obtained via the generalized Wiener-Hopf technique for arbitrary impedance wedges using a numerical-analytical approach. The numerical results show the spectral properties of the fields, GTD/UTD diffraction coefficients, and total field
Wiener Zeitung : österreichische Tageszeitung seit 1703
No full text1780,1(1.Jan.) - 1805,26(30.März); 1848,180(1.Juli) - 1940,29.Febr.; 238.1945,21.Sept. -1944,Juli - 1945,20.Sept. nicht ersch.; Periodizität: 6x wöchentl., anfangs: 2x wöchentl., später: 3x wöchentl.Ungezählte Beil.: Amtsblatt zur Wiener Zeitung und Zentralanzeiger für Handel und Gewerbe; Außerordentliche Beil.; Extra-Beil.; 1903,8.Aug.: Jub.-Festnr. der Kaiserlichen Wiener Zeitung 1703-1903; Extra-Bl.; Beil.; ab 2013,5.Juli: Wiener Journa
Path analysis of Wiener Process
No full textIn this thesis we research and introduce several properties of paths of a Wiener process. At first we present a way to prove existence of a Wiener process and then we discuss its basic properties. The second chapter is devoted to analytical properties of Wiener's paths including monotonicity, differentiability, Hölder continuity and quadratic variation. In the third chapter we research the reflection principle and the distribution of maxima of paths in the case of a random walk and then also in the case of a Wiener process. The fourth chapter concentrates on the Skorohod embedding and its application in the proof of the classic central limit theorem. Finally, using the results of the first chapter we simulate a path of a Wiener process and illustrate some of the properties discussed earlier. To demonstrate the concepts, several problems were included in the relevant chapters together with an author's solution. Powered by TCPDF (www.tcpdf.org
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