Purpose is to study influence of a longwall face advance on the geomechanical situation in the neighbourhood of a mining site based upon determination of changes in standard and critical subsidence of the immediate roof rocks. Methods. To study a geomechanical situation in the neighbourhood of a mining site the authors have applied software product GeoDenamics Lite developed at Dnipro University of Technology. The software product relies upon a calculation procedure of stress-strain state of rocks by Professor O.V. Savostianov. Expediency of the software selection is based upon the supported control and adaptation of a coal mining technique to changes in geodynamic stress fields in the anisotropic rock-coal medium impacting temporal and spatial changes in the technological parameters. Findings. The basic problems have been singled out connected with certain changes in a longwall face advance. For the first time, an analytical scheme of tangential stresses within the immediate roof rocks has been developed for Lisova mine of SE Lvivvuhillia under the conditions of coal seam mining by means of the paired longwalls which makes it possible to determine both physical and geometrical parameters of standard loads within the formation. Originality. Dependencies of temporal and spatial changes in subsidences and horizontal displacements of rock layers of the immediate roof have been defined being 5.2 m for the upper rock pack and 3.9 m for the lower pack if the longwall longwall face advance is 1.9 up to 4.8 m/day. Both physical and geometrical parameters of the reference pressure have been defined as well as the parameters of lower sandstone pack in the process of the main roof subsidence. Impact of the extra pressure forces on the immediate roof rocks has been analyzed at the moment of critical lowerings of the immediate roof rocks. In this context, standard loading from the overlying formation in addition to tangential stresses in the roof result in rock failure due to vertical cracks above a longwall face. Practical implications. The engineering methods have been developed making it possible to identify impact parameters of a longwall face advance on the geomechanical situation in the neighbourhood of a mining site. In future, it will help forecast changes in the reference pressure around a longwall face while preventing emergency settlement of the powered support.

Currently, companies in the energy sector are focus on sustainable growth, although they face many challenges, including the peculiarities of their operations. One of the features of companies in the energy sector is the need for effective communication with the media and the public. This is of paramount importance due to the current trends and challenges in the energy sector, the market requirements and the low level of development in such companies. The object of this study invovles the employees of the communication departments of energy sector companies, while the subject is the intensification of their activities based on the use of motivational tools. The authors chose the tools of the game theory, which is a game that the company and employees of the project team engage in when implementing information and communication projects. The study developed a method for motivating the employees of communication departments, which based on the game theory, allows the formation of many possible parameters of the optimal structure of fixed and commission remuneration payments for the employees to maximize their utility, depending on the propensity or unwillingness of these employees to take risks, which contributes to the development of staff motivation tools. This method was applied to the activities of several Ukrainian energy companies. The proposed approach differs from the existing ones based on the opportunity to intensify the activity of the employees of the communication departments, taking into account their willingness to take risks in each case, and will increase the interest of such personnel in the effective implementation of each stage of the information and communication project, better meet the needs of the end-users and ultimately affect the sustainable growth of energy companies.

Nowadays, the Ukrainian electricity industry is experiencing difficult conditions, as it is operating in a mode of depletion of its production potential. At the same time, the transition to sustainable and renewable energy is the necessary basis for the country’s welfare and for ensuring its energy security. Therefore, today we cannot do without the additional attraction of sources of funding from investors. The purpose of the survey is to study the pattern and effectiveness of investments and identify links and dependencies between key technical and economic parameters and investments in renewable energy sources. To achieve this goal, the authors divided the study into four successive stages, which made it possible to study the subject of the study comprehensively. As a result of the study, results have been obtained that complement the existing theoretical, methodological, and practical developments. Mathematical calculations (using the example of the largest wind power plants in the south-eastern region) revealed transparent relationships and dependencies between the critical technical and economic parameters of the WPP of South-Eastern Ukraine and investments in the wind energy sector. Among them: the installation of 1 MW of additional WPP generating capacity requires an average of EUR 1.51 million of investment resources, and the production of one additional kWh of electricity requires an investment EUR 0.42 euros; therefore, providing an additional thousand households with WPP electricity is possible with an investment of EUR 1.345 million.

Additive manufacturing is a technology that creates objects by adding successive layers of material. The 3D method is an alternative to subtractive production, in which production involves removing material from the initial solid. 3D printing requires the initial design of the manufactured object using computer design, for example, one of the following programs: CAD, 3DCrafter, Wings 3D, Cinema 3, Blender, 3ds Max, Autodesk Inventor, and others. It is also possible to scan an existing object to be manufactured using 3D printing technology. An important element of Industry 5.0 is 3D printing technology, due to its favorable environmental orientation and production flexibility. Three-dimensional printing technology uses recycled materials such as powders. Therefore, it can be part of a circular economy, contributing to environmental protection. Additive manufacturing not only complements existing technologies by enabling rapid prototyping but also plays a fundamental role in sectors such as dentistry and medicine. This article consists of seven chapters relating to various aspects of 3D printing technology in the context of the assumptions and challenges of Industry 5.0. It examines the environmental impact and recycling potential of 3D printing technology, illustrates the economic integration of this technology within various industries, and discusses its future development prospects.

Purpose. To study the impact of digital maturity of energy enterprises on achieving the effects of sustainable development in the conditions of the fourth industrial revolution. Methodology. The study on energy enterprises economic efficiency was based on the results of a statistical analysis of their activity economic indicators and a macroeconomic analysis of the prerequisites for the digitalization of Ukrainian energy companies, as well as considering the results of an analytical study of foreign companies digital transformation. The application of the benchmarking method made it possible to highlight the best examples of digital changes of energy companies in the field of sustainable development. The generalization method made it possible to point out the effects of digitization of sustainable development for energy companies. Findings. Effectiveness of energy enterprises due to the implementation of digital transformation is reasoned, which allows achieving the effect of sustainable development by ensuring environmental, economic, and social development. Based on the calculation of economic efficiency values, the most efficient energy enterprise was determined, whose activity is characterized by the highest level of digital transformations aimed at achieving the goals of sustainable development. Originality. The dependence between the level of digital maturity of energy enterprises and their economic efficiency is substantiated. The spheres of energy enterprises activity have been established, whose efficiency and importance increases with the level of digitalization. The technical characteristics of energy enterprises digitalization in the spheres of implementation of sustainable development goals, namely economic, social, and environmental ones, are highlighted. Practical value. The main directions of energy enterprises activity have been determined based on the selection of the effects of sustainable development, which are achieved thanks to digitalization. The efficiency of the enterprise because of digitalization is substantiated, considering the directions of sustainable development.