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To reveal the dynamic response characteristics of the foundation of mined-out areas (MOA) under the high-speed railway (HSR) load is important for predicting settlement and safety assessment of the foundation. Taking MOA of Dianshang under the Taiyuan-Jiaozuo HSR as the engineering background, the model experiments and numerical analysis were employed to reveal the dynamic response of both subgrade and the foundation of the HSR, as well as the attenuation law of the acceleration in the overlying strata of the MOA. Results show that within the full frequency range of the HSR load, the dynamic response of the foundation increases with the increase in load frequency. When the depth exceeds 6 m, the dynamic response of the foundation initially increases and subsequently decreases with the increase in load frequency. Contrasted with singlepoint loading, the superposition effect and moving effect of the HSR load will form a dynamic response superposition zone within 1-4 m below the subgrade, leading to a significant enhancement of the dynamic response of the foundation. Compared to HSR axle load, the driving speed of HSR has a greater impact on the acceleration of both the subgrade and foundation. The obtained conclusions provide a reference for the safety operation of the HSR crossing the MOA. [ABSTRACT FROM AUTHOR]

The purpose of this study is to outline the current problems with the company's documentation workflow process and propose a plan to implement a new automated system to eliminate waste and improve the company's cash flow. Every enterprise is required to accurately record business operations. Accounting is the foundation of an organization, serving not only to meet legal requirements, but also to support management processes. In the case of large enterprises, complex accounting carries the risk of problems with timely and correct accounting, which can lead to delays in payments, reminders, collection procedures and interruptions in deliveries. As a result, it becomes crucial to put processes in place to safeguard liquidity. The study includes an analysis of the company's current documentation workflow process and identification of problems associated with it. A plan is then proposed to implement a new automated system to eliminate waste. The methodology is based on an analysis of the company's internal data and available technological solutions. The main results of the study include the identification of existing problems in the documentation workflow process and a plan for implementing a new system. The findings indicate that improving process efficiency can help increase the company's cash flow. The study introduces a new perspective on records management in enterprises, especially in the context of eliminating waste and improving liquidity. The theoretical value of the work lies in identifying opportunities for effective records management in the context of supporting business processes. The introduction of an automated documentation workflow system can bring practical benefits, such as reducing payment delays, avoiding debt collection procedures and improving the overall efficiency of business operations. [ABSTRACT FROM AUTHOR]

Research background: Sharing economy is an economic system in which assets and services are shared between individuals. It is peer-to-peer based activity of sharing and obtaining to goods, services, and resources. The functioning of sharing economy platforms and specifically shared transportation of goods and services is still an area that is not fully explored. It is necessary to pay attention to the profitability of the platforms, but in addition to economic indicators, it is also necessary to deal with environmental issues, which are directly connected with these facts. Purpose of the article: The study deals with how revenue and profitability are achieved by shared transportation platforms, specifically the platforms Bolt Services SK, Uber Slovakia, Wolt Slovakia and Bistro Slovakia considering their operation within the territory of the Slovak Republic. Following this issue, the study reveals which economic and environmental benefits the shared transportation system can bring. Methods: Methods of determining the profitability of selected sharing economy platforms in the field of transport and delivery services are used in the studies. Environmental factors are explored through studies by authors dealing with this issue. Findings & Value added: The main findings of the study point to the unstable situation of platforms operating in the segment of shared transport and delivery services. Through profitability analysis, we were able to find out the fact that the global COVID-19 pandemic has affected the operation of shared transportation platforms in various ways. The unstable profitability of platforms for the shared transportation of people, goods and services was observed especially in the time before the COVID-19 pandemic. During the pandemic, we observed positive changes in profitability, or there was almost no worsening of the financial situation during the pandemic. [ABSTRACT FROM AUTHOR]

Budgets in organisational units are considered to be traditional management support tools. On the other hand, budgetary control is the essence of control measures, allowing for the increase in the efficiency of an enterprise through appropriate allocation of resources. The methodology used in the analysis of budget variances (obtained as a result of applying budgetary control) undoubtedly influences the management efficiency of almost every organizational unit. The authors indicate a research gap of methodological and application nature in the area of risk measurement in the analysis of budget variances. Therefore, the aim of the article is to create universal and flexible models enabling probabilistic quantification of the risk of budget variance regardless of the nature of the cost, the person budgeting and the budgeting unit. Extreme value theory was used to develop the model. The results of the work are models allowing for the estimation of the limit level of deviation for assumed probabilities and models determining the level of deviation for a given probability level. The application of these models in budgetary control will allow for a synthetic assessment of the degree of budget execution in the company, comparing the quality of budget execution over time as well as between units, defining the limits of materiality of budget variances. For the purpose of model verification, the authors have used budget variances of cost energy consumption, which have been determined on the basis of empirical distributions obtained from data coming from the system of budgetary control implemented at a university located in a larger European city. [ABSTRACT FROM AUTHOR]

Due to the current ecological situation in the world, the demand for renewable energy is growing. Its use does not burden the environment because resources are renewed in a short time, unlike traditional fuels - coal or oil. It can be concluded that the main task of humanity is to choose the appropriate technology for obtaining renewable energy and adapt it to local conditions. The aim of the work is to present the technical, economic and environmental potential of using the wave energy of the Baltic Sea and the possibility of converting this energy into electricity. The theoretical and technical potential of sea wave energy that Poland could use was estimated. The most advanced methods of converting wave energy into electricity were presented, and the most promising technical solutions were selected for use in the Polish Exclusive Economic Zone and off the coast of our country. The selection of the most promising technologies - single and combined wave energy converters was based on reports on the operation of the first experimental wave power plants and wave converters operating in other waters. In terms of technology and economics, obtaining energy from sea waves is much more difficult than using solar or wind energy. However, along with the development of offshore wind farms and access to the infrastructure of the National Power System and the need to give up traditional, emission-related energy sources, wave power plants may have a chance for development in the Polish energy sector. It is an untapped source of renewable energy with great energy potential. [ABSTRACT FROM AUTHOR]

Aiming to the requirements of potential safety risk control along the high-speed railway, taking the foundation of Taijiao high-speed railway above the mined-out area of Dianshang, China as the engineering background, a mechanical model of composite rock strata of the foundation was established based on the theory of thin plate. Combined with the catastrophe theory, the evaluation system of the foundation stability was constructed. Using the selfdeveloped similar model test and rainfall device, the deformation stability of the foundation under the condition of heavy rainfall and dynamic loading of the high-speed railway was analyzed. Results show that the maximum influence depth of the dynamic loading and heavy rainfall on the foundation is about 20 m, and the further compaction of the foundation cracks is the main factor leading to the subsidence of the foundation above the mined-out area. In addition, the increase of the number of longitudinal tensile cracks in the foundation, which gradually plays a dominant role in the new cracks, shows an exponential growth trend. Being affected by the continuous heavy rainfall, the deformation evolution of the foundation displays four stages: the initial stabilization, the slow deformation, the first sudden-jump, and the secondary sudden-jump stages. Among them, the surface's maximum deformation occurs in the secondary sudden jump stage. The conclusions obtained in this study provide a theoretical basis for the stability evaluation and treatment of the foundation of the high-speed railway above the mined-out area. [ABSTRACT FROM AUTHOR]

The soft-hard composite coal seam composed of tectonic and primary structural coal has the problems, such as high gas content, high pressure, poor permeability and difficult extraction, which seriously affect the production safety in the mining. To study the evolution characteristics of pressure relief in soft-hard composite coal seam based on directional hydraulic flushing technology, taking Hudi coal mine in China as the engineering background, and the pressure relief effect of directional hydraulic flushing on 'two soft and one hard' composite coal seam was studied by theoretical analysis and numerical simulation. The stress evolution of the whole coal seam under a single hole and porous interaction of different flushing radii were analyzed. The field test of directional hydraulic flushing in tectonic soft coal seam similar to protective layer mining was conducted. Results show that when the flushing diameter is 3-4 m, the influence range of stress disturbance covers the whole coal seam, and the vertical stress relief of the primary coal seam is the largest, which provides a theoretical basis for coal seam pressure relief and permeability enhancement technology. The average daily gas extraction (ADGE) concentration has doubled, and the ADGE purity has increased from 0.03 m3/d to 1.07m3/d. The target period of gas extraction is shortened from the expected 6 months to 1 month, and the average daily driving speed of coal roadway increases from 2.32 m/d to 5.37 m/d. The gas extraction efficiency is significantly improved, and the risk of gas outburst is effectively reduced, which has important theoretical and practical significance for improving the pressure relief and permeability enhancement efficiency of the soft and low permeability coal seam. [ABSTRACT FROM AUTHOR]

Geothermal energy can be an attractive source of renewable energy in many respects. The purpose of this paper is to assess the role of geothermal energy in the West Pomeranian Region of Poland. The article presents the key principles of geothermal energy development, its role, functions and perspectives in fostering renewable energy usage in the region in question. Strengths, weaknesses as well as opportunities and threats of using geothermal energy are analysed based on the literature review. A regional geothermal energy development model is proposed. The study is based on statistical data. The results of the conducted study show that geothermal energy can be an important source of regional energy supply in the West Pomeranian Region. However, advantages and shortcomings should be taken into account when deciding on the promotion of geothermal energy in the selected region. [ABSTRACT FROM AUTHOR]