Positivity and Stability of Coupled Differential-Difference Equations with Time-Varying Delays

2017 ◽  
pp. 107-115
Author(s):  
Jun Shen
Keyword(s):  
Difference Equations ◽  
Time Varying

Simulating and analyzing artificial nonstationary earthquake ground motions

1982 ◽  
Vol 72 (2) ◽  
pp. 615-636
Author(s):  
Robert F. Nau ◽  
Robert M. Oliver ◽  
Karl S. Pister
Keyword(s):  
Difference Equations ◽  
Kalman Filters ◽  
Ground Motions ◽  
Structural Response ◽  
Model Parameters ◽  
Time Varying ◽  
Nonparametric Method ◽  
Linear Difference Equations ◽  
Earthquake Ground Motions ◽  
Earthquake Accelerograms

Abstract This paper describes models used to simulate earthquake accelerograms and analyses of these artificial accelerogram records for use in structural response studies. The artificial accelerogram records are generated by a class of linear linear difference equations which have been previously identified as suitable for describing ground motions. The major contributions of the paper are the use of Kalman filters for estimating time-varying model parameters, and the development of an effective nonparametric method for estimating the variance envelopes of the accelerogram records.

Discrete Verhulst model based on a linear time-varying

2014 ◽  
Vol 4 (2) ◽  
pp. 299-310 ◽  
Author(s):  
Xia Long ◽  
Yong Wei ◽  
Zhao Long
Keyword(s):  
Differential Equations ◽  
Difference Equations ◽  
Design Methodology ◽  
Linear Time ◽  
Original Data ◽  
Time Varying ◽  
Sequential Simulation ◽  
Content Type ◽  
Verhulst Model ◽  
Practical Implications

Purpose – The purpose of this paper is to build a linear time-varying discrete Verhulst model (LTDVM), to realise the convert from continuous forms to discrete forms, and to eliminate traditional grey Verhulst model's error caused by difference equations directly jumping to differential equations. Design/methodology/approach – The methodology of the paper is by the light of discrete thoughts and countdown to the original data sequence. Findings – The research of this model manifests that LTDVM is unbiased on the “s” sequential simulation. Practical implications – The example analysis shows that LTDVM embodies simulation and prediction with high precision. Originality/value – This paper is to realise the convert from continuous forms to discrete forms, and to eliminate traditional grey Verhulst model's error caused by difference equations directly jumping to differential equations. Meanwhile, the research of this model manifests that LTDVM is unbiased on the “s” sequential simulation.

scholarly journals Oscillatory Behavior in Linear Difference Equations under Unmodeled Dynamics and Parametrical Errors

2007 ◽  
Vol 2007 ◽  
pp. 1-18 ◽  
Author(s):  
M. De la Sen
Keyword(s):  
Difference Equations ◽  
Oscillatory Behavior ◽  
Unmodeled Dynamics ◽  
Time Varying ◽  
Linear Difference Equations ◽  
Oscillating Solutions ◽  
General Conditions

This paper investigates the presence of oscillating solutions in time-varying difference equations even in the case when there exist parametrical errors (i.e., errors in the sequences defining their coefficients) and/or unmodeled dynamics, namely, the current order is unknown and greater than the nominal known order. The formulation is related to the concepts of conjugacy, disconjugacy, positivity, and generalized zeros and general conditions of oscillation are obtained both over particular intervals and for the whole solution. Some results concerned with the presence of stable oscillations are also presented.

Sign in / Sign up

Export Citation Format

Share Document