AGH (Akademia Górniczo-Hutnicza) University of Science and Technology: Journals
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Interaction of silty loam soil on the change of soil retention capacity and soil compaction following subsoiling
Full text linkThe subsoiling of arable soils as part of a strategy against excessive compaction and the resulting plow pan can be successfully used as a pro-retention treatment. The study of changes in the physical and water properties of soil as a result of subsoiling was carried out on three sites: Wojnowice, Strzybnik, and Owsiszcze, located in the Racibórz district, Śląskie Voivodeship (Poland), in a silty-loam soil. A total of five soil profiles (0–150 cm) were analyzed before and after subsoiling. The experiment used a seven-tine Maschio subsoiler at a depth of 50–60 cm between 2012–2014. The physical (e.g., soil bulk density, soil organic matter) and water (e.g., maximum water capacity, field water capacity, permanent wilting point, total plant available water) properties of the soil were determined before and after subsoiling, taking into account the division into layers: 0–25 cm, 25–50 cm, and 50–150 cm. Statistical analyses were used to check changes in soil physical and water parameters. The results show that the subsoiling treatment caused a statistically significant decrease in soil compaction (bulk density) at all three layers and increased moisture in the range of total plant available water in the subsoil layer (25–50 cm). Subsoiling in silty-loam soil will enable the soil’s retention potential to be used, especially in dry years
The impact of COVID-19 on the global renewable energy sector. An integrative review exploring the challenges and emerging opportunities
No full textThe shift from traditional fossil fuel energy to cleaner, renewable energy has the potential to help achieve long-term sustainability goals. The COVID-19 pandemic has had a significant impact on the renewable energy sector. This study aims to provide an integrative review of the global impacts and challenges of the COVID-19 pandemic on the renewable energy sector and highlight the energy-related lessons and emerging opportunities by capturing the main trends in the field. First, the integrative review identifies five themes. Second, the study identifies the aspects of renewable energy that are influenced by the COVID-19 pandemic. Third, the study proposes a conceptual framework highlighting the impacts and challenges of the COVID-19 pandemic on renewable energy demand and consumption patterns, and these results are further supported by the aggregate dimensions identified through inductive analysis. The three main energy challenges are: the healthcare sector primarily dealing with disease control; associated environmental impacts with challenges relating to fluctuating and uncertain energy demand and consumption, structural and pattern changes, greenhouse gas emissions, local air quality, energy transmission infrastructure, and oil production and transmission network; associated economic impact dealing with industrial activities including households, agriculture, public and commercial sector, energy import/ export, sales revenue and expenditure, social sector factors, funding schemes, and subsidies, technology R&D, and overall economic welfare. The study also makes theoretical and practical propositions for researchers and policymakers
Preliminary comparative analysis of underground thermal energy storage, shallow and deep geothermal energy solutions for sustainable district heating in Poland
Full text linkThis paper explores shallow and deep energy technologies supporting Poland’s district heating transition, focusing on aquifer thermal energy storage (ATES), borehole thermal energy storage (BTES), deep geothermal energy, and energy piles. Heating accounts for a major share of energy consumption and emissions in Poland, where district heating networks are essential for urban energy supply. National policies promote renewable energy integration and energy security, presenting opportunities for geothermal and underground thermal storage solutions. ATES and BTES offer seasonal heat storage by cycling thermal energy in subsurface aquifers and boreholes respectively, balancing variable heat demand and renewable supply. Deep geothermal energy provides stable base-load heat via extraction from deep reservoirs, contributing reliable renewable heat despite requiring significant investment and geological specificity. Energy piles represent an innovative technology, combining building foundation piles with embedded heat exchangers, enabling efficient ground heat use for heating and cooling without additional land or deep drilling. This method is especially suited for urban environments and contributes to cost-effective decarbonization. The paper compares technical principles, geological conditions, performance, economic and environmental aspects of these technologies, highlighting their complementary roles in enhancing heat network flexibility, efficiency, and sustainability. The findings inform strategic planning and policy development to optimize Poland’s renewable heat infrastructure, supporting climate targets and energy independence for widespread adoption
An empirical analysis of changes in the Błędów Desert using machine learning methods
Full text linkThe aim of the study was to determine changes in the land cover of the Błędów Desert, which is a habitat for rare flora and fauna species protected under the Natura 2000 program. Invasive plants, which pose a threat to protected species, are present in this area. Additionally, human activities can have negative impacts on the desert ecosystem. Therefore, the land manager is obligated to carry out actions aimed at maintaining the appropriate size and character of the desert. The analysis was conducted using satellite imagery from the Sentinel-2 mission, which provides images with high temporal and spatial resolution. The study covered the years 2015–2022 and took into account seasonal variability due to the presence of green vegetation. Change detection methods based on data integration, including photointerpretation and machine learning classification, were used for land cover analysis. Five representative land cover classes were defined, enabling a quantitative presentation of changes in the Błędów Desert and a qualitative assessment of the classification performed. The results of the study indicate variability in land cover depending on the season, with an increasing number of protected plant species, including grasslands. Simultaneously, a slight increase in the desert area was noted, manifesting as an increase in sand in forested areas. The results obtained demonstrate the effective implementation of the Natura 2000 program objectives
Spatial variation on hydrogeochemical parameter in the Hetauda Valley, central Nepal
Full text linkWater is a requisite source for human survival, facing increasing issues and challenges in terms of both quantity and quality due to exacerbated global populations and urbanization trends. This increased demand has caused a decline in the overall availability and quality of water resources. Hetauda, serving as the administrative center of Bagmati Province, has emerged as a key destination for employment services along with a good potential zone for geotourism closely connected to its diverse geological features and water resources. However, excessive utilization, depletion, and extensive pollution of surface water sources in the region have underscored the importance of exploring groundwater for agricultural, and domestic needs along with decreasing the possibilities for geotourism. As the study area lies in the Hetauda Valley, to address this concern, water samples from 34 different sources such as dug wells, boreholes, and springs were collected. A thorough analysis of physicochemical parameters was conducted to evaluate water quality, revealing notable variations across locations, including the presence of iron and arsenic traces in specific samples. The Weighted Arithmetic Index Method was used to calculatethe Water Quality Index (WQI) showing that certain water sources had very good quality while few weren’t appropriate for human consumption. The Piper diagram indicates the dominancy of calcium ions in cations and chloride in anions. The stiff diagram shows that the ions Na + K > Ca > Mg dominate the composition of the cations, whilst HCO₃⁻ > Cl⁻ > SO₄²⁻ dominates the anions. Besides, the multivariate statistical analysis through Principal Component Analysis was executed to support these hydrochemical findings. In conclusion, this research underscores the critical necessity for sustainable water management strategies in the study area, advocating for the prudent exploration of groundwater while addressing the challenges posed by contaminants, thus ensuring the availability of safe and sufficient water resources in the region
Possibilities of Applying the Vom Berg Rheological Model in Research on Polymer-Modified Drilling Muds
No full textThis article examines the potential application of the Vom Berg rheological model in the technology of polymer-modified drilling muds. In recent years, intensive research has been conducted at the Faculty of Drilling, Oil, and Gas to optimize procedures for selecting rheological models for technological fluids used in drilling operations. One of the key outcomes of this research is the proprietary RheoSolution methodology, applied in this study to assess the adaptability of the Vom Berg rheological model. Originally developed for analyzing the rheology of cement slurries in civil engineering, this model has been utilized here to describe the relationship between shear stress and shear rate in polymer-modified drilling muds.As part of the research, laboratory experiments were conducted at the Drilling Fluids Laboratory of the Faculty of Drilling, Oil, and Gas, focusing on drilling muds modified with xanthan biopolymer. The obtained results served as the basis for a comparative analysis of the classical API methodology and the proposed RheoSolution approach in determining the rheological parameters of the tested fluids. Special attention was given to the applicability of the Vom Berg model as a tool for a more precise characterization of drilling mud behavior under dynamic conditions. This article is part of a broader series of publications aimed at demonstrating the utility and potential advantages of the RheoSolution methodology in studies on the rheological properties of technological drilling muds
Using Splitter Ordering Heuristics to Improve Bisimulation in Probabilistic Model Checking
Full text linkModel checking is used to verify computer-based and cyber-physical systems, but faces challenges due to state space explosion. Bisimulation minimization reduces states in transition systems, easing this issue. Probabilistic bisimulation further simplifies models with stochastic behaviors. Recent techniques aim to improve time complexity of iterative methods in computing probabilistic bisimulation for stochastic systems with nondeterministic behaviors. In this paper, we propose several techniques to accelerate iterative processes to partition the state space of a given probabilistic model to its bisimulation classes. The first technique applies two ordering heuristics for choosing splitter blocks. The second technique uses hash tables to reduce the running time and the average time complexity of the standard iterative method. The proposed approaches are implemented and run on several conventional case studies and reduce the running time by one order of magnitude on average
Refugees\u27 perception of the shape of Europe: The case from Kos
No full textW 2016 roku przeprowadzono 49 wywiadów swobodnych z migrantami na greckiej wyspie Kos oraz kilkanaście rozmów na pograniczach węgiersko-serbskim oraz macedońsko-greckim. Wywiady wzbogacone zostały prośbą o narysowanie mapy Europy. Analiza uzyskanych map szkicowych wykazała wyraźny zachodocentryzm, egocentryzm przestrzenny, wpływ doświadczenia „drogi” na percypowanie przestrzeni oraz percepcję liniową przestrzeni, przypominającą historyczne materiały kartograficzne tras pielgrzymkowych.In 2016, 49 interviews were conducted with migrants on the Greek island of Kos, as well as a several conversations on the Hungarian-Serbian and Macedonian-Greek borders. The interviews were supplemented with a request to draw a map of Europe. The analysis of the obtained sketch maps revealed a clear West-centrism, spatial egocentrism, the influence of the experience of the "road" on the perception of space, and a linear perception of space, reminiscent of historical maps of pilgrimage routes
Geotourism along the Annapurna Mountain Range
Full text linkNepal is more explained by its natural beauty of mountain, which have been formed due to continental collision during geological past of approx. 22 million years ago. The Mountain Range of Nepal holdsa huge geological history and are rich in geological units of Higher Himalayan Crystalline and Tibetan Tethys Sedimentary Sequence. Each year tourists from different countries visit Nepal for the glorious high hill peak trekking and mountaineering. Tourists are more curious about the minerals, gemstones and rocks of Nepal Himalaya. This paper presents the geology along the Annapurna Mountain Range, so that the tourist can visualize the geological evolution during geological time period. Literature review holds a major part in this research work. Various geological information was collected and used to finalize this research work. Maps, cross sections, and photographs are the main output of this paper