This paper proposes extended least-squares (ELS) for ARMAX model identification of continuous-time and certain discrete-time systems. The schemes have a relaxed strictly positive real (SPR) condition for global convergence. The relaxed SPR scheme is achieved by introducing overparametrization and prefdtering but without introducing ill-conditioning. The schemes presented are the first such prop...

The meaning of nonzero set points for the identiiability of the AR-MAX model parameters in a closed-loop system with a minimum-variance controller is explained and discussed. It is pointed out that, in the case of a zero set point and an ARMAX model resulting from the discretization of a continuous-time plant, the model parameters cannot be identiied in a closed-loop system with a minimum-varia...

El objetivo de esta investigación es analizar las relaciones internacionales entre países miembros la Comunidad Andina Naciones (CAN) y su efecto en el flujo comercio internacional Ecuador los miembros. Se consideran dos perspectivas. La primera analiza cambio significativo que pudieron tener exportaciones hacia CAN. segunda considera puedan importaciones provienen Para modelar series se un m...

BACKGROUND More patient-specific medical care is expected as more is learned about variations in patient responses to medical treatments. Analytical tools enable insights by linking treatment responses from different types of studies, such as randomized controlled trials (RCTs) and observational studies. Given the importance of evidence from both types of studies, our goal was to integrate thes...

A new control algorithm has been developed for linear stochastic ARMAX systems subjected to arbitrary random inputs. The purpose is to make the shape of the output probability density function (PDF) to be as close as possible to a target PDF. A feedback control function is formulated to re-configure the open-loop linear system into a non-linear closed-loop system, where the vector of control pa...

This paper deals with the weighted minimum-variance self-tuning regulation of stochastic time-varying systems, which can be described by linear input-output mathematical models. We consider the input-output ARMAX mathematical models with unknown time-varying parameters. The recursive extended least squares RELS algorithm, which can be applied to the stochastic time-varying systems, is presented...

Abstract. This paper shows that the matrix fraction description, given by a pair {A(z) B(z)} of matrix polynomials of z, for a linear time-invariant system may not be unique even if A(z) is monic, A(z) and B(z) have no common left factor, and the matrix coefficients corresponding to the highestorder terms of A(z) and B(z) are full row rank. The orders of all possible matrix fraction description...

Smart materials have been widely used for control actuation. In this paper, we present a microscale position control system using a novel electroactive polymer (EAP). We built a third-order model based on the system identification of the EAP actuator with an autoregressive moving average with exogenous input (ARMAX) method using a chirp signal input from 0.01 Hz to 1 Hz with the magnitude limit...