**Commenced**in January 2007

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**Edition:**International

**Paper Count:**32451

##### Order Reduction by Least-Squares Methods about General Point ''a''

**Authors:**
Integral square error,
Least-squares,
Markovparameters,
Moment matching,
Order reduction.

**Abstract:**

The concept of order reduction by least-squares moment matching and generalised least-squares methods has been extended about a general point ?a?, to obtain the reduced order models for linear, time-invariant dynamic systems. Some heuristic criteria have been employed for selecting the linear shift point ?a?, based upon the means (arithmetic, harmonic and geometric) of real parts of the poles of high order system. It is shown that the resultant model depends critically on the choice of linear shift point ?a?. The validity of the criteria is illustrated by solving a numerical example and the results are compared with the other existing techniques.

**Keywords:**
Integral square error,
Least-squares,
Markovparameters,
Moment matching,
Order reduction.

**Digital Object Identifier (DOI):**
doi.org/10.5281/zenodo.1080074

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