Publications by authors named "J Martinka"

Article Synopsis
  • Machine learning (ML) for predicting vector or tensor properties requires maintaining proper invariance with molecular rotation, unlike energy prediction which is simpler due to its scalar nature.
  • The proposed "rotate-predict-rotate" (RPR) technique involves three steps: rotating the molecule to align with its principal axes, predicting the vector property in that orientation, and then transforming the prediction back to the original orientation.
  • This RPR approach ensures covariance for vector properties and can extend to tensors, allowing for rapid training of accurate ML models across numerous molecular configurations.
View Article and Find Full Text PDF

Optically transparent wood is a type of composite material, combining wood as a renewable resource with the optical and mechanical properties of synthetic polymers. During this study, the effect of monochromatic UV-C (λ-250 nm) radiation on transparent wood was evaluated. Samples of basswood were treated using a lignin modification method, to preserve most of the lignin, and subsequently impregnated with refractive-index-matched types of acrylic polymers (methyl methacrylate, 2-hydroxyethyl methacrylate).

View Article and Find Full Text PDF

Unlabelled: This paper deals with the recognition of selected burning liquids by convolutional neural networks (CNNs). Three CNNs (AlexNet, GoogLeNet and ResNet-50) were trained, validated and tested (in the MATLAB 2020b software) for the recognition of selected liquids (ethanol, propanol and pentane) using photographs of the flames they produce. For training, validation and test photographs of the liquids under investigation burning in a 106-mm-diameter vessel were used.

View Article and Find Full Text PDF

This study focuses on the energy potential and combustion process of torrefied wood. Samples were prepared through the torrefaction of five types of wood: Ash, beech, oak, pine and spruce. These were heated for 2 h at a temperature of 300 °C under a nitrogen atmosphere.

View Article and Find Full Text PDF

The objective of the work was to improve the leaching resistance of fire-retardant (FR) modified wood by the incorporation of a thermoset resin. Here, Scots pine ( L.) sapwood was impregnated with melamine formaldehyde (MF) resin and hydrophilic FRs guanyl-urea phosphate/boric acid by a vacuum-pressure treatment.

View Article and Find Full Text PDF