In this study, a novel rotary cleaning device was used for the separation and cleaning of wheat grains. This research analyzed the influence of the inclination angle of the sieve drum (K) of the device on the quality of these processes. In this article, the results obtained for four selected rotational speeds (n_b) of the sieve drum are presented. The quality of the separation and cleaning of the wheat grains was evaluated using three cleaning process parameters: coefficient of plump grain mass separation (W_z), coefficient of fine impurities separation (W_d), and total coefficient of cleaning effectiveness (E). Based on statistical analysis of the results, the inclination angle of the sieve drum had a significant effect on the quality of the wheat grain separation process. Coefficient W_z was highest for sieve drum inclination angles of K = 0° and K = 2.5°, whereas W_d was highest for K = -2.5°. The total coefficient of cleaning effectiveness (E) was characterized by different values for different inclination angles of the sieve drum. Keywords: Cleaning effectiveness, Conical sieve, Rotary cleaning device, Wheat grain cleaning.

This paper addresses the issue of metrological accuracy of instantaneous in-cylinder pressure measurement in a diesel engine test bed. In studies, the central unit has been the single-cylinder AVL 5402 engine. The pressure measurement was performed with a sensor designed for thermodynamic analysis, and the results were related to the crank angle, where two rotations corresponding to the four-stroke working cycle were denoted as angles between −360° and +360°. The novelty of this paper is the proposition of how to perform a type A uncertainty estimation of the in-cylinder pressure measurement and to assess its repeatability. It was demonstrated that repeatability of the measurement during the ignition process was difficult to estimate because of the phenomena that cannot ensure the repeatability conditions. To solve the problem, two methods were proposed. In one method, the pressure was measured in the subsequent cycles immediately after the ignition was turned off, and in another method, the engine was driven by a starter. The latter method provided maximal pressure values much lower than during usual tests. The obtained repeatability of measured pressure was %EV = 0.4%, which proved high capability of the evaluated measurement system.

Agricultural biogas plant operations are energy sources that fit well with rural land use. The continuous increase in cattle and pigs creates the need to manage animal waste, especially slurry. Using it for energy production in biogas plants offers the possibility of obtaining electricity, heat, and highly efficient manure. The thermal energy generated in an agricultural biogas plant is used to heat the substrate in the fermentation process and can also be used to heat buildings, dry fodder, or wood. Electricity can be used to cover the farm’s needs and sold to an energy company. However, the energy generated in the biogas plant must be of the right quality. One of the main factors describing the quality of electricity is the voltage distortion from the sinusoidal waveform. This paper presents the results of a study of the impact of biogas plant operation on the course of voltage and current in the grid. The theoretical analysis of the voltage distortion mechanism at the point of connection of an agricultural biogas plant was based on a simplified power system model consisting of a voltage source and the equivalent impedance of the power system. According to the theoretical analyses, agricultural biogas plant operation should reduce the voltage distortion factor. In order to confirm this statement, field tests were carried out at three agricultural biogas plants, based on which an analysis was made of the impact of the power generated in the biogas plants on the value of voltage distortion occurring at the point of their connection. However, the field tests did not confirm the conclusion of the theoretical analysis. Only in one case (where the biogas plant was connected near a substation and there was the highest short-circuit power) could it be seen that an increase in generation affected the voltage distortion factor. In the other two cases, generation did not significantly affect the shape of the voltage waveform. However, in each of the biogas plants studied, as the generation power increased, the current distortion factor decreased, suggesting that agricultural biogas plants should operate as close to the rated power as possible.

The aim of the study was to determine the impact of red light (RL) and effective microorganisms (EMs) on the wheat yield of grain and straw, as well as the quality (protein, carbohydrates, gluten, index of sedimentation (SDS index), germination capacity). Moreover, the experiments measured the granulometric composition and pH of soil, as well as its content of microelements and major nutrients, including heavy metals. The field experiment was conducted in 2017, 2018, and 2019 at the experimental station (Felin) of the University of Life Sciences in Lublin (Poland). The best results in terms of overall yield, protein content, and SDS index were obtained after the red light treatment (RL). The three-year application of effective microorganisms (EMs) in the soil had a positive impact, relative to the control, on the grain yield, straw yield, starch, SDS index, and germination capacity. A slight decrease was observed in terms of the protein content. After the application of effective microorganisms (EMs) in soil, changes were observed in the soil’s granulometric composition, pH, humus, and microelements.

The driver's reaction time is one of the most important parameters for the road pre-accident analysis. There are known the results of tests, in which the value of this parameter was determined in expected and unexpected road situations. But in some cases, this time may be longer e.g. in situations in which the driver's attention may be distracted by keeping observations other than the area, in front of the car's surroundings. There are many manoeuvres, when the driver is obliged to observe many areas at the same time. Thus, his attention must be turned away from the main area – in front of the vehicle. The paper presents the results of tests involving the measurement of the driver's attention time focused on observing the surrounding other than the car's path. During the test, the driver's attention was focus on observing the side and back mirror, car radio and at the mobile phone. Certain values can be potentially considered as extending the typical driver's reaction time. The results of the presented tests have practical applications and can be used in the process of issuing opinions on traffic accidents.

The paper presents the concept of use of fuels produced from production waste (RDF). The usefulness of RDF processed into pellets used in the chemical and power industry was also analyzed. The paper presents the results of research on the quality and content of selected elements in RDF pellets. The values of individual indexes are within the ranges typical for fuels manufactured from plastics. The tested material’s humidity was identified as low, as well as the content of chlorine, sulfur and other elements. In the working condition, the calorific value of the tested sample was 25.260 MJ·kg⁻¹ and was above the range of typical values for RDF (13-20 MJ·kg⁻¹). The moisture content in the tested material was 1% and it was within the required range. In the laboratory tests, the content of chlorine and sulfur was also determined.