Model reduction based on limited‐time interval impulse response Gramians

2019 ◽  
Author(s):  
Deepak Kumar ◽  
Ahmad Jazlan ◽  
Victor Sreeram
Keyword(s):  
Model Reduction ◽  
Impulse Response ◽  
Time Interval ◽  
Limited Time ◽  
Limited Time Interval

scholarly journals Modelling the Structure of the Ringed Spiral NGC 4736

1996 ◽  
Vol 157 ◽  
pp. 253-255
Author(s):  
Wim van Driel ◽  
Pieter Mulder ◽  
Françoise Combes
Keyword(s):  
Mass Distribution ◽  
Spiral Structure ◽  
Optical Spectra ◽  
Spectral Lines ◽  
Time Interval ◽  
Limited Time ◽  
The Galaxy ◽  
Dynamical Simulations ◽  
Pattern Speed ◽  
Limited Time Interval

AbstractWe studied the ringed RSab(r)-type spiral NGC 4736, which has a probably slightly oval disk and a very small bar. We mapped the galaxy in the HI and Hα spectral lines and we obtained long-slit optical spectra. These data were modeled using a 2-D gas dynamical code. The 2-D potential used is axisymmetric in the inner and outer regions and oval (b/a=0.8) at intermediate radii only. The oval component rotates at a pattern speed of 40 km s–1 kpc–1, close to the observed value. Inner and outer rings, like those observed, form at the inner and outer Lindblad resonances, though they co-exist only during a limited time interval in the simulations. The morphology and kinematics of the inner ring and spiral structure as observed in neutral and ionized hydrogen can be well understood in terms of gas dynamical simulations, given the form of the (stellar) potential. What remains to be explained is the origin of the nonaxisymmetric features in the mass distribution defining the potential.

Model Based Targets Matching from Image Frames

2011 ◽  
Vol 341-342 ◽  
pp. 748-752
Author(s):  
Xin Wang ◽  
Jin Wang
Keyword(s):  
Image Sequence ◽  
Image Point ◽  
Time Interval ◽  
Limited Time ◽  
Feature Points ◽  
Model Based ◽  
Moving Platform ◽  
Limited Time Interval

We present a new algorithm to locate targets by matching image frames taken from a moving platform. We have noticed that an image point is environment sensitive, but those energy changes of grouped points have their own statistical similarities in two image frames within limited time interval. This approach analyzes correspondence of energy points around every feature points between inter-frames in image sequence in order to decide those feature points. Successful results are given for a vide frames.

Resonant Wave-Particle Interaction in Nonuniform Plasmas

1971 ◽  
Vol 26 (9) ◽  
pp. 1528-1530
Author(s):  
L. Saitta ◽  
F. Engelmann
Keyword(s):  
Particle Interaction ◽  
Time Interval ◽  
Limited Time ◽  
Linear Dynamics ◽  
Wave Particle Interaction ◽  
Resonant Wave ◽  
Parabolic Potential ◽  
Resonant Effect ◽  
Special Case ◽  
Limited Time Interval

Abstract The appearance of resonant-particle effects in the linear dynamics of electron waves in a plasma whose electrons are trapped in a potential trough is discussed and conditions for the characteristic times involved are derived. For the special case of a parabolic potential trough it is shown that, within a limited time interval, a strong resonant effect may occur, due to the interaction of a wave with all particles, which is not contained in the solutions given so far.

scholarly journals Detection of Short-Step Pulses Using Practical Test-Functions and Resonance Aspects

2008 ◽  
Vol 2008 ◽  
pp. 1-15 ◽  
Author(s):  
Alexandru Toma ◽  
Cristian Morarescu
Keyword(s):  
Second Order ◽  
Order System ◽  
Time Interval ◽  
Limited Time ◽  
Large Step ◽  
Working Frequency ◽  
Second Order Systems ◽  
Intelligent Methods ◽  
Physical Quantities ◽  
Limited Time Interval

An important aspect in modeling dynamic phenomena consists in measuring with higher accuracy some physical quantities corresponding to the dynamic system. Yet for measurements performed on limited time interval at high working frequency, certain intelligent methods should be added. The high working frequency requires that the measurement and data processing time interval should be greater than the time interval when the step input is received, so as to allow an accurate measurement. This paper will show that an intelligent processing method based on oscillating second-order systems working on limited time interval can differentiate between large step inputs (which are active on the whole limited time interval) and short step inputs (which are active on a time interval shorter than the limited working period). Some resonance aspects (appearing when the input frequency is close to the working frequency of the oscillating second-order system) will be also presented.

Sign in / Sign up

Export Citation Format

Share Document