نتایج جستجو برای: الگوی armax

تعداد نتایج: 44509  

Journal: :Environmental Modelling and Software 2016
Fabio Oriani Andrea Borghi Julien Straubhaar Grégoire Mariethoz Philippe Renard

The direct sampling (DS) multiple-point statistical technique is proposed as a non-parametric missing data simulator for hydrological flow rate time-series. The algorithm makes use of the patterns contained inside a training data set to reproduce the complexity of the missing data. The proposed setup is tested in the reconstruction of a flow rate time-series while considering several missing da...

2017
André A.B. Klein Peter Spreij André Klein

An approach is presented to get interconnections between the Fisher information matrix of an ARMAX process and a corresponding solution of a Stein equation. The case of algebraic multiplicity greater than one and the case of distinct eigenvalues are addressed. Appropriate links are constructed for these two cases by applying a factorization both for the Fisher information matrix and for a corre...

Journal: :Jornal brasileiro de pneumologia : publicacao oficial da Sociedade Brasileira de Pneumologia e Tisilogia 2011
José Laerte Rodrigues da Silva Júnior Thiago Fintelman Padilha Jordana Eduardo Rezende Eliane Consuelo Alves Rabelo Anna Carolina Galvão Ferreira Marcelo Fouad Rabahi

OBJECTIVE To evaluate the effect that seasonality has on the occurrence of respiratory symptoms in a Brazilian city with a tropical climate. METHODS This was a cross-sectional study, in which data related to subjects who sought outpatient treatment at a primary health care clinic in the city of Goiânia, Brazil, were correlated with daily meteorological data. Over a one-year period, all the pa...

2011
N. Bolf T. Rolich

Fractionation product properties of crude distillation unit (CDU) need to be monitored and controlled through feedback mechanism. Due to inability of on-line measurement, soft sensors for product quality estimation are developed. Soft sensors for kerosene distillation end point are developed using linear and nonlinear identification methods. Experimental data are acquired from the refinery dist...

ژورنال: مرتع و آبخیزداری 2009
علی سلاجقه, علی فتح آبادی محمد مهدوی

یکی از پیچیده‌ترین فرآیندهای هیدرولوژیکی فرآیند بارش-رواناب است,‏ که از پارامترسهای مختلف فیزیکی و هیدرولوژیکی تاثیر می‌پذیرد. در این پژوهش با بهره‌گیری از روش‌های آماری ARMAX, شبکه عصبی, عصبی-فازی (ANFIS با جداسازی خوشه‌ای و شبکه‌ای) و دو مدل بدست آمده از ترکیب آنها به منظور مدل‌سازی فرآیند بارش-رواناب و پیش‌بینی جریان رودخانه بهره‌گیری شد. به طوری که درآغاز ساختار بهینه هر یک از مدل‌ها تعیین ...

2011
Anders Hansson Ragnar Wallin

In this paper we derive the maximum likelihood problem for missing data from a Gaussian model. We present in total eight di erent equivalent formulations of the resulting optimization problem, four out of which are nonlinear least squares formulations. Among these formulations are also formulations based on the expectation-maximization algorithm. Expressions for the derivatives needed in order ...

2009
Jakob Kjøbsted Huusom Niels Kjølstad Poulsen Sten Bay Jørgensen John Bagterp Jørgensen

ARX models, is a suitable model class for linear control implementations. The parameter estimation problem is convex and easily handed for both SISO and MIMO system in contrast to ARMAX or State Space model. Model predictive control implementations insuring offset-free tracking are discussed and related. Special attention is given to an adaptive disturbance estimation method with time-varying f...

2014
Alamelu Nachiappan

The control theory and automation technology is widely used in industries. Many control algorithms are based on the mathematical models of dynamic systems. Mathematical models and parameter estimation are basics for automatic control. A recursive least squares parameter estimation algorithms and Kaczmarz’s projection algorithm is applied based on ARMAX model and OE models. The estimated paramet...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید