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Z. Nikolaou

Publications and source records attributed to Z. Nikolaou.

2 recordsLinked to original sources

pyDOF: a Python library for the design of discrete forward and inverse filters

In this work, we present pyDOF, a Python-based software library which provides a domain-specific framework for the design of symmetric, physical-space, forward as well as inverse discrete filters. pyDOF is based on a constrained optimisation framework developed in our previous work [1, 2]. This framework allows the user to impose a wide range of constraints on the discrete filter transfer-function such as monotonicity, positivity, value-fixing, gradient-smoothing etc. amongst many others. pyDOF additionally includes an adaptive filter stencil selection option, and a van Cittert-based inverse-filter design with a user-controlled reconstruction order. The filter coefficients are computed automatically, and saved to a plain text file which can be readily parsed by any programming language. pyDOF can be used to design a wide range of low-pass, high-pass, multi band-pass/band-stop etc. discrete filters. In addition, due to its generality and abstraction, pyDOF can be used to design specific filters for user-defined target filter transfer functions. Although developed primarily for application to computational fluid dynamics simulations, pyDOF can be used to design discrete filters for a wide range of signal processing applications.

physics.comp-ph

RePlaChem: A dimensionality reduction library for plasma chemical mechanisms

In this work, we present RePlaChem, a software library for reducing detailed large-scale plasma chemical mechanisms to smaller skeletal ones. The library parses a plasma chemical mechanism in the well-established format compatible with the software ZDPlasKin, runs the reduction algorithm, and generates automatically a skeletal chemical mechanism. This feature allows the seamless implementation of the skeletal chemistry in well-known solvers including ZDPlasKin. In turn, the reduction of the chemistry accelerates otherwise computationally expensive numerical simulations. Furthermore, RePlaChem can be used as an analysis tool to shed light into the underlying reaction physics by identifying the dominant species and associated reactions. In order to validate and demonstrate its capabilities, RePlaChem is used to substantially reduce a large-scale methane-hydrogen plasma chemical mechanism with 77 species and 4404 reactions at various orders with a relatively small loss of accuracy. GitHub: https: // github. com/ znikolaou/ RePlaChem. git

physics.comp-ph