This paper presents the implementation of the signal processing algorithm used by buoy DIFAR (Directional Frequency Analysis and Recording), that is fully operational on Polish Navy anti-submarine warfare (ASW) helicopters and ships, applied to dipping sonars for detection and tracking of submarines. The development of the DSP algorithms was a part of the modernization of sonars conducted at the Gdansk University of Technology....

The study of informal employment is still associated with several obstacles, from the scope of definition, through measurement methods, to policy recommendations. This article aims to revise the existing methodological frames in order to point out how to improve the study of informal employment in CEE countries. The case of Poland serves to examine whether the common definitions and measurement methods are suitable for an inclusive...

The main aim of this article is to point out the possible measures of how to improve the study of informal employment in developed countries. We choose the case of Poland to examine whether the existing definitions and measurement methods are suitable for indicating the prevalence of informal employment. Firstly, we present the most popular definitions of informal employment, secondly we show the existing research on informal employment...

A polyurethane (PU)-based powder coating reinforced with vinyltrimethoxysilane (VTMS)-functionalized ZrO2 nanoparticles (V-ZrO2) for thermal stability was developed. Chemical structure, microstructure and thermal degradation kinetics of the prepared coatings were investigated. The peak of aliphatic C–H vibrating bond in the Fourier transform infrared (FTIR) spectrum of V-ZrO2 was a signature of VTMS attachment. Scanning electron...