This paper presents an experimental evaluation of lateral protection devices of N3 category vehicles in accordance with UNECE Regulation No. 73. The aim of the study was to assess their compliance with the prescribed geometric and mechanical criteria on the basis of a summarized analysis of twenty tests, as well as to examine their deformation behaviour and structural stiffness. The tests were carried out in an accredited laboratory under the conditions specified in the regulation, applying a 1 kN horizontal static load and taking measurement uncertainty into account. The study evaluated the geometric parameters of the devices, the distances to vehicle structural elements, gap sizes, and deformations in the load application zones. The results showed that, in all analysed cases, the tested devices complied with UNECE Regulation No. 73, and the measured deformations did not exceed the permissible limits. The results indicate that the investigated structural solutions provide sufficient mechanical stiffness and may support further improvement of the design and testing methodology of lateral protection devices
This article presents a practical process-supervision interpretation of a broader calibration analysis that relates low-frequency radial (i.e., normal-direction) peak-to-peak displacement to surface roughness in finish turning of EN AW-2011 aluminum alloy. The study uses only a 190-record synchronized displacement-roughness analysis subset obtained in one controlled machine-tool-sensor setup. The regression calibration showed very strong within-dataset relations: Ra = 14,204 + 24,191V (R² = 0,9929, RMSE = 0,052 µm) and Rz = 63,207 + 105,253V (R² = 0,9905, RMSE = 0,264 µm). For operational interpretation, displacement values were divided into three empirical bands: low, medium, and high. Mean roughness increased monotonically across these bands, from Ra = 14,512 µm and Rz = 64,547 µm in the low band to Ra = 16,076 µm and Rz = 71,362 µm in the high band. An additional one-way ANOVA confirmed statistically significant differences between the bands (p < 0,001). The results support the use of displacement bands as a setup-specific warning logic for roughness-related supervision. However, the bands should not be treated as universal limits, because the data represent one time-ordered calibration sequence, and no independent validation set was used.
The article analyses the methodological conditions under which low-frequency normal-direction vibration displacement can be used as an indicator of surface roughness in turning. The work is presented as an applied methodological analysis based on a previously published experimental case involving finish turning of EN AW-2011 aluminium alloy, synchronized displacement-roughness records, and contact profilometry measurements reported as Ra and Rz. The numerical analysis is based on 190 synchronized records. Within the analysed setup, the internal calibration yielded R² = 0.9929 and RMSE = 0.052 µm for Ra, and R² = 0.9905 and RMSE = 0.264 µm for Rz. The article emphasizes that low-rate displacement data should not be interpreted as chatter diagnostics or as a universal predictive model. Instead, such data can support setup-specific process-state monitoring when the sensing direction, sampling limitations, calibration procedure, error range and profilometric validation are explicitly defined. The analysis shows that a simple normal-direction displacement indicator can be useful in low-complexity monitoring environments, provided that it is periodically checked against direct roughness measurements and recalibrated after changes in material, tooling, machine setup or sensor mounting.
Paper describes simulation results of inverter model based on proposed converter with two transistor switch-es using Matlab. The aim of this research to investigate behavior of proposed model of the micro inverter based on proposed converter, when inverter operates autono-mously (islanding) and running parallel in the local electricity network. The simulation of inverter’s operation on autonomous mode using nonlinear load was performed, as well as it runs in parallel with the local power network polluted with harmonics. The main goal of these simulations is to observe the response of output current of inverter to the harmonical distortions of local grid. Examination of inverter model based on proposed converter in Matlab environment helps to determinate the resistance of inverter output signal to distortion in local electrical grid using two working modes: 1. the autonomous mode using nonlinear load; 2. the parallel mode with local electric grid polluted by higher order harmonics.
Summary The article assesses the impact of inward and outward foreign direct investment on value added tax revenue in European Union countries. The empirical study is based on panel data for 27 EU member states covering the period 2003-2023 and applies least squares regression with HAC standard errors. The results show that outward FDI has a statistically significant positive direct effect on VAT revenue, while inward FDI is not significant in the contemporaneous model. Lagged models reveal that outward FDI increases VAT revenue in the first and fourth years after investment, whereas inward FDI exerts a negative effect in the first year after investment. The findings indicate that the fiscal effect of FDI depends on investment direction, export-import structure and the timing of the effect. Therefore, investment promotion policy should be evaluated not only by the volume of attracted FDI, but also by its contribution to domestic value creation and tax revenue dynamics.
