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In the face of ongoing climate changes and the current geopolitical situation, Renewable Energy Sources (RES) are continuously gaining popularity in many countries. Objectives related to environmental protection and the use of RES set by different countries all over the world, as well as by the European Union (EU), are becoming priorities for many. The increase in the installed capacity of photovoltaic systems has been growing steadily for several years, leading to the creation of new systems accompanying PV installations; this phenomenon has also been observed in Poland. This paper presents a photovoltaic system in the form of a bicycle shed next to a school building as an example of building-integrated photovoltaics (BIPV) without connection to the power grid. It was shown that the energy consumption profile should be properly correlated with the production profile, otherwise significant losses occur. Alternative methods to improve the correlation of production and energy consumption by using SCADA systems or building automation to properly manage the electricity generation and consumption installation were also proposed. Furthermore, it was shown that adopting a fixed discount rate in financial analyses can distort the picture of real profits. An analysis of the changes in the NPV ratio using variable discount rates was carried out when analyzing the entire life of the solar plant. [ABSTRACT FROM AUTHOR]

This paper presents the use of computed tomography for the evaluation of hardfacing. The method used in this research is hardfacing by tungsten inert gas using alloy wires of wear resistant layers. This paper discusses the latest materials used for hardfacing and their application. It characterizes the defects of obtained hardfacing and impact of the type of wire on the concentration of defects. It further, the basic mechanical properties of coatings were determined. The results are subjected to qualitative and quantitative analysis. The smallest average percentage of defects in relation to the overall surface is observed for the hardfacing EL-600 HB, which amounts to 1.5%. The highest average percentage of defects in relation to the overall surface is observed for the hardfacing EL-500 HB, which amounts to 7.2%. The chemical composition of hardfacing has been presented. [ABSTRACT FROM AUTHOR]

The aim of the present article is the assessment of technical shear resistance (technological shear) of orthopedic screw made of titanium alloy Ti6Al4V, produced using incremental technology in the process of 3D printing process. The first part of the work presents incremental techniques in production engineering. The second part of the present work contains a specification of the 3D printing process of samples as well as the description of the used material. The fundamental part of the article is composed out of endurance tests for orthopaedic screws as well as the analysis of the obtained results and conclusions. The method of incremental production SLM using SLM 280HL metal printer was used during the technological process. The resistance tests were performed using ZWICK/ROELL Z150 machines. Identical endurance trials were performed for monolithic bars made of titanium alloys (of bar core size ) made on a wire electric discharge machine Sodick SL600Q for comparative purposes. The obtained test results enabled comparative assessment of the value of shear resistance Rt in the conditions of technological shear. According to the performed tests, the shear resistance Rt of orthopaedic screws is nearly 33% lower than of monolithic bars of the same core size. [ABSTRACT FROM AUTHOR]

Apart from accuracy, one of the parameters describing industrial robots is positioning accuracy. The parameter in question, which is the subject of this paper, is often the decisive factor determining whether to apply a given robot to perform certain tasks or not. Articulated robots are predominantly used in such processes as: spot welding, transport of materials and other welding applications, where high positioning repeatability is required. It is therefore essential to recognise the parameter in question and to control it throughout the operation of the robot. This paper presents methodology for robot positioning accuracy measurements based on vision technique. The measurements were conducted with Phantom v2511 high-speed camera and TEMA Motion software, for motion analysis. The object of the measurements was a 6-axis Yaskawa Motoman HP20F industrial robot. The results of measurements obtained in tests provided data for the calculation of positioning accuracy of the robot, which was then juxtaposed against robot specifications. Also analysed was the impact of the direction of displacement on the value of attained pose errors. Test results are given in a graphic form. [ABSTRACT FROM AUTHOR]