Model-free deconvolution of femtosecond kinetic data

Estimation Accuracy of the Electric Field in Cable Insulation Based on Space Charge Measurement

Space charge measurement accuracy is crucial when assessing the suitability of cables for high-voltage direct current (DC) systems. This study assembled state-of-the-art analysis technologies, including time-domain deconvolution, to mark electric field estimation accuracy, which the present techniques achieve. The pulse electroacoustic method was applied to a 66 kV-class extruded cable, and waveforms were obtained and analyzed to reproduce the electric field distribution. The DC voltage was set to be sufficiently low so that the analysis results can be compared with Laplace’s equation. The statistical analysis of 81 waveforms under a DC voltage of 30 kV showed that the estimation accuracy was −0.3% ± 19.9% with a 95.4% confidence interval, even with the deconvolution parameter optimized. The estimated accuracy using the “reference” waveform is applied to waveforms at higher voltages since similar estimation accuracies were confirmed for waveforms obtained under a DC voltage of 45 kV.

Non-steady scaling model for the kinetics of the photo-induced free radical polymerization of crosslinking networks

A unified model expressed in closed-form is elaborated for the kinetics of free-radical polymerization and successfully compared to experimental data.

Determination of tip transfer function for quantitative MFM using frequency domain filtering and least squares method

Magnetic force microscopy has unsurpassed capabilities in analysis of nanoscale and microscale magnetic samples and devices. Similar to other Scanning Probe Microscopy techniques, quantitative analysis remains a challenge. Despite large theoretical and practical progress in this area, present methods are seldom used due to their complexity and lack of systematic understanding of related uncertainties and recommended best practice. Use of the Tip Transfer Function (TTF) is a key concept in making Magnetic Force Microscopy measurements quantitative. We present a numerical study of several aspects of TTF reconstruction using multilayer samples with perpendicular magnetisation. We address the choice of numerical approach, impact of non-periodicity and windowing, suitable conventions for data normalisation and units, criteria for choice of regularisation parameter and experimental effects observed in real measurements. We present a simple regularisation parameter selection method based on TTF width and verify this approach via numerical experiments. Examples of TTF estimation are shown on both 2D and 3D experimental datasets. We give recommendations on best practices for robust TTF estimation, including the choice of windowing function, measurement strategy and dealing with experimental error sources. A method for synthetic MFM data generation, suitable for large scale numerical experiments is also presented.