The subject of this article is the problem of payment gridlocks and their significance for the enterprise sector and the risks they cause. The authors’ attention is focused here on presenting the essence of payment gridlocks, their consequences, as well as the causes on the sides of both the debtor and the creditor. In the empirical part of the article, the authors focused on assessing the problem of payment backlogs in selected mining and energy-production companies in Poland. A study on selected companies from this industry was conducted, the purpose of which was to show the scale of delayed payments with the particular identification of those that are payment backlogs (i.e. a delay of at least 60 days). Five major companies from the energy industry in Poland were selected for the study, representing both the mining and energy production sectors. These companies are Polska Grupa Górnicza SA, Jastrzębska Spółka Węglowa SA, ENEA SA, Energa SA and TAURON Polska Energia SA According to the available data, payment terms in this sector are the longest in the European Union compared to other sectors of the economy. In Poland, the situation is no different in this respect. This is especially visible in the mining industry, which is perceived as very risky when it comes to timely payments. Undoubtedly, reducing payment gridlocks in this industry is a difficult task, which results from its specificity and the number of problems it is struggling with, which have been additionally reinforced by the Covid-19 pandemic.

Research on automatic translation has recently become a very popular field of study for linguists. The process of adjusting data collected from language to meet the machine’s potential and efficiency requires the knowledge and use of an accurate and effective methodology. The linguist’s task is not only to feed data collected from traditional language dictionaries into the computer’s memory, but it is also necessary to take into consideration all the relations that hold among the elements being described, as the aim of automatic translation is to enable the system to carry out an accurate and effective translation of texts. The paper is also an attempt to show how the object oriented approach proposed by W. Banyś resolves the problem of polysemy of words in a natural language which is one of the major problems in computer assisted translation. For the computer assisted translation to be exhaustive and effective, a process of disambiguation of a polysemous word should be carried out thus enabling a correct generation of its equivalents in a target language, which is presented on the basis of the English causative verb open.

Three phase induction motors are widely used in industrial processes and condition monitoring of these motors is especially important. Broken rotor bars, eccentricity and bearing faults are the most common types of faults of induction motors. Stator current and/or vibration signals are mostly preferred for the monitoring and detection of these faults. Fourier Transform (FT) based detection methods analyse the characteristic harmonic components of stator current and vibration signals for feature extraction. Several types of simultaneous faults of induction motors may produce characteristic harmonic components at the same frequency (with varying amplitudes). Therefore, detection of multiple faults is more difficult than detection of a single fault with FT based diagnosis methods. This paper proposes an alternative approach to detect simultaneous multiple faults including broken rotor bars, static eccentricity and outer/inner-race bearing faults by analysing stator current and vibration signals. The proposed method uses Hilbert envelope analysis with a Normalized Least Mean Square (NLSM) adaptive filter. The results are experimentally verified under 25%, 50%, 75%, 100% load conditions.

The paper discusses a way of choosing the design features (geometry, the rate of grinding and thrust) of ring-ball mills. Various methods of calculating the optimal rate of grinding have been compared. Basing on experimental investigations on the pilot-plant and industrial scale, the influence of the angular velocity and the thrust on the mill have been verified, and the interdependence between the rate of grinding and the thrust of the grinding elements have been explained.

The paper there presents the analysis of low-cycle fatigue test results of 30 HGSA alloy steel obtained with the use of two methods. In the standard method, fatigue tests were performed with the use of many specimens, and in the simplified method, the results were defined in an incremental step test using one specimen. Test results were analysed taking into account the influence of loading form on the course of a stabilization process with defined material data. The analysis of the stabilization process in diversified conditions of loading was performed by comparison of the stress amplitude CTa and strain amplitude Eap for the same levels of total strain amplitude Eac• Basing on the tests, one could state that both methods of defining the cyclic properties lead to qualitatively and quantitatively convergent results. The results exhibit qualitative similarity as far as the character of courses of changes determined in different periods of life of n' and K' parameters of the cyclic strain chart is concerned, and quantitative similarity of the values of determined parameters.

Dynamic development in children’s research has led to surprising discoveries about the learning and thinking patterns of fetuses, infants and young children. These studies have revolutionized not only our knowledge of children, but also our understanding of the nature of the human mind and brain. Moreover, within this context, it is believed that many areas of adulthood are the result of the experiences and changes that occur during the fetal period and in childhood. These experiences, therefore, are crucial for human development and what people achieve in the following stages of their lives. The results of the research on brain development during the fetal period and during childhood presented here, reveal a new perspective for understanding the essence and nature of the learning process. These studies also strongly suggest that the first two thousand days of a child’s life are critical in developing many basic human skills. Therefore, we must take great care of the quality of environment for a child’s development.

The theoretical analysis of the charge exchange process in a spark ignition engine has been presented. This process has significant impact on the effectiveness of engine operation because it is related to the necessity of overcoming the flow resistance, followed by the necessity of doing a work, so-called the charge exchange work. The flow resistance caused by the throttling valve is especially high during the part load operation. The open Atkinson-Miller cycle has been assumed as a model of processes taking place in the engine. Using fully variable inlet valve timing the A-M cycle can be realized according to two systems: system with late inlet valve closing and system with early inlet valve closing. The systems have been analysed individually and comparatively with the open Seiliger-Sabathe cycle which is a theoretical cycle for the classical throttle governing of the engine load. Benefits resulting from application of the systems with independent inlet valve control have been assessed on the basis of the selected parameters: fuel dose, cycle work, charge exchange work and a cycle efficiency. The use of the analysed systems to governing of the SI engine load will enable to eliminate a throttling valve from the system inlet and reduce the charge exchange work, especially within the range of part load operation.