A software for inversion of multiexponential decay datafor Windows system


V. Bortolotti, R.J.S. Brown, P. Fantazzini

© 2012 Alma Mater Studiorum – Università di Bologna


UpenWin is a 32 bit application for Windows (currently tested under windows 98, XP, Vista, Seven, 8 and 10), developed in C++ and MFC (Microsoft Foundation Class) by means Visual Studio 2017, that implements an interface to facilitate the use of UPEN (Uniform PENalty) and its related input files.

It is composed by a simple SDI (Single Document Interface) window with many dialog boxes. By means of the dialogs the user can pre-process the data file using the appropriate T1 or T2 program filter, sets the value for the parameters, both for UPEN and program filter, and run a computation session.

Parameters can be set also in the initial parameter file, by clicking the “par” menu button and proceeding to the desired parameter file (such as Upenpar.par), making any needed changes, and saving or not saving as desired.


The red shows non-default parameters.

The display shows the evolution of the iteratively computed distribution and allows control of parameters from the keyboard.


UpenWin is marketed by University of Bologna.

UPEN stands for Uniform PENalty inversion of multiexponential decay data. The name refers to the application of negative feedback to a smoothing “penalty” function to prevent excessive detail in distributions of relaxation times.  This allows appropriate smoothing of both sharp peaks and broad features in the same distribution, allowing the sharp peaks without breaking broad features into multiple peaks not required by the data. This allows meaningful computation of the rms noise and supports additional UPEN objectives, which include identifying various data features and data problems, giving a series of diagnostics and warnings and allowing processing options.

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Upen Manual download

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