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Automatic optimization of industrial robotic workstations for sustainable energy consumption
(MDPI, 2026) Wierbica, Rostislav; Krejčí, Jakub; Babjak, Ján; Kot, Tomáš; Krys, Václav; Bobovský, Zdenko
Industrial robotic workstations contribute substantially to the total energy demand of modern manufacturing, yet most existing energy-saving approaches focus on modifying robot trajectories, motion parameters, or the position of the robot’s base. This paper proposes a novel methodology for the automatic optimization of the spatial placement of a fixed technological trajectory within the robot workspace, without altering the task itself. The method combines pre-simulation filtering of infeasible configurations, large-scale energy simulation in ABB RobotStudio, and real measurement using a dual acquisition system consisting of the robot’s controller and an external power meter. A digital twin of the workstation is used to systematically evaluate thousands of candidate positions of a standardized trajectory. Experimental validation on an ABB IRB 1600–10/1.2 confirms a 23.4% difference in total energy consumption between two workspace configurations selected from the simulation study. The non-optimal configuration exhibits higher current draw, greater power variability, and a more intensive warm-up phase, indicating increased mechanical loading arising purely from geometric placement. By providing a scalable, trajectory-preserving approach grounded in digital-twin analysis and IoT-based measurement, this work establishes a data foundation for future AI-driven predictive and adaptive energy optimization in smart manufacturing environments.
Investigating the dynamics of (3+1)-dimensional generalized nonlinear physical system via sensitivity and phase portraits
(Springer, 2025) Iqbal, Muhammad; Riaz, Muhammad Bilal; Rehman, Muhammad Aziz ur
This article presents new exact wave solutions for the generalized (3?1)-dimensional nonlinear wave equation involving gas bubbles. The ðG0=G2Þ-expansion method is used to find solutions that behave like as periodic, bell-shaped, cubic, and kink ways, as well as solutions that are rational functions. We also provide two-dimensional and three-dimensional plots, as well as corresponding contour plots, using appropriately selected parameters. We further transform the system into a planar dynamical system and analyze the obtained solutions through phase portraits. The qualitative analysis of the evaluated model employs the concepts of bifurcation and chaos. Furthermore, by using an external force, we verify the manifestation of quasi-periodic and chaotic behaviors. We explore a number of different approaches for identifying chaos, including time series and phase patterns in both three and two dimensions. Moreover, we conduct a sensitivity analysis that takes into account various initial conditions. We obtained unique results that demonstrate that the methods we provided for checking soliton solutions and phase drawings for a variety of nonlinear models are effective and useful.
Property tax trends in the Czech Republic
(Emerald Publishing Limited, 2026) Krajňák, Michal
PurposeThis study aims to deal with the taxation of immovable property in the Czech Republic. This tax is significant revenues for the budget of the municipalities where the immovable property is located.Design/methodology/approachTo achieve this paper's objective, the author used standard positivist economic methodology. For a dependency analysis between the examined factor, regression analyses were used.FindingsThe tax rates changed only twice over the whole analysed period 1993-2024. It also follows that the share of property tax in the total tax revenue is decreasing. Due to the increase in the market price of the property, there is tax regressivity. The real tax burden on building plot increased only in municipalities with up to 600 inhabitants; in all other municipalities and cities, there is a decrease. Municipalities have options to increase tax revenue and tax burden. Many municipalities do not use this provision, even though the regression analysis results valid a positive impact on tax revenue.Research limitations/implicationsA slight limitation of this study is the fact that the amount of the tax revenue for the year 2025 is not included in the input database. This data are not available.Practical implicationsIn this study, there are practical recommendations which could be implemented into legislation. These recommendations are in the area of property valuation or the area of implications of inflation to tax rates.Social implicationsProperty tax reflects social and societal aspects. This is characterised by the fact that permanent residential properties have lower tax rates. Furthermore, in municipalities with a smaller population, the tax burden on permanent residential properties is lower. The reason is the different levels of infrastructure.Originality/valueAnalysis long period from the setting up of the Czech Republic to the present time.
Influence of 3D printing conditions on physical-mechanical properties of polymer materials
(MDPI, 2025) Beníček, Lubomír; Vašina, Martin; Hrbáček, Pavel
The popularity of 3D printing technology is rapidly increasing worldwide. It can be applied to metals, ceramics, composites, hybrids, and polymers. Three-dimensional printing has the potential to replace conventional manufacturing technologies because it is cost effective and environmentally friendly. This paper focuses on the influence of 3D printing conditions on the physical and mechanical properties of polylactic acid (PLA), poly(methyl methacrylate) (PMMA), and poly(ethylene terephthalate glycol-modified) (PETG) materials produced using Fused Deposition Modeling (FDM) technology. The impact of nozzle diameter, layer height, and printing temperature on the mechanical (i.e., bending stiffness and vibration damping) and physical (i.e., sound absorption and light transmission) properties of the studied polymer materials was investigated. It can be concluded that 3D printing conditions significantly influenced the structure and surface shape of the 3D-printed polymer samples and, consequently, their physical and mechanical properties. Therefore, it is essential to consider the type of filament used and the 3D printing conditions for specific 3D-printed material applications.
Creep resistance and microstructure evolution in P23/P91 welds
(MDPI, 2025) Vodárek, Vlastimil; Holešinský, Jan; Kuboň, Zdeněk; Palupčíková, Renata; Váňová, Petra; Malcharcziková, Jitka
This paper summarizes the results of investigations into heterogeneous P23/P91 welds after long-term creep exposure at temperatures of 500, 550 and 600 °C. Two variants of welds were studied: In Weld A, the filler material corresponded to P91 steel, while in Weld B, the chemical composition of the consumable material matched P23 steel. The creep rupture strength values of Weld A exceeded those of Weld B at all testing temperatures. Most failures in the cross-weld samples occurred in the partially decarburized zones of P23 or WM23 steel. The results of the investigations on the minor phases were in good agreement with kinetic simulations that considered a 0.1 mm fusion zone. Microstructural studies proved that carburization occurred in the P23/P91 weld fusion zones. The partial decarburization of P23 steel or WM23 was accompanied by the dissolution of M7C3 and M23C6 particles, and detailed studies revealed the precipitation of the Fe2 (W, Mo) Laves phase in decarburized areas. Thermodynamic simulations proved that the appearance of this phase in partially decarburized P23 steel or WM23 is related to a reduction in the carbon content in these areas. According to the results of creep tests, the EBSD investigations revealed a better microstructural stability of the partially decarburized P23 steel in Weld A.