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Świat od nowa. Tom 2: Duchowość w sztuce Śląska Cieszyńskiego w XX wieku
No full text368 str.Krakówmonografiawersja wydawnicz
Managerial Economics
No full textIn the experiment underlying the St. Petersburg paradox, we use state-dependent linear utility functions for money with a countably infinite set of states of nature to show that a potential participant will be willing to pay no more than a finite sum of money to participate in the experiment.Krakówwersja wydawnicz
Geomatics and Environmental Engineering
No full text"This study examines the issue of the accuracy of physical surface calculations for land plots with complex configurations and reliefs. The goal of the study was to develop a methodology for determining the surface area of land plots with complex configurations and reliefs. The presented model was based on the finite element method. The developed method allows one to evaluate a relief’s complexity by using a dimensionless mean physical surface complexity factor"," a Fortran program was developed for the methodology. Experiments that proved the effectiveness of the methodology and a comparative analysis of those areas that were calculated by the presented method and TIN model were carried out. The research findings proved the practicability of the methodology for calculating the physical surfaces of land plots with complex configurations. The presented methodology can be used for flood modeling, landscape and vertical planning, etc."Krakówwersja wydawnicz
Geology, Geophysics & Environment
No full textThis paper evaluates the geothermal potential of the Main Dolomite formation in an oil and gas field on the Fore-Sudetic Monocline (SW, Poland). The reservoir characterization included a well-logging interpretation and developed 3D petrophysical and temperature models that provided information on storage potential, transport properties, and temperature conditions in the analyzed carbonate formation. Geothermal energy potential was assessed using heat in place (HIP) and recoverable heat (Hrec) parameters for water and systems, considering a 50-year plant lifespan. Petrophysical and temperature data classify reservoirs using unsupervised machine learning, identifying zones with high and low geothermal potential, noting a strong limestone and dolomite dichotomy. Dolomite horizon shows more promising reservoir quality with mean porosity and permeability of 0.045 and 0.4 mD, respectively, however, its mean thickness reaches 11.58 m at maximum. The calculated Hrec for a 50-year lifetime of a geothermal system varies across dolomite horizon. In the most promising areas of NNW, WSW, and E parts, the values of Hrec are 8.19, 3.47, and 1.34 MW for water, respectively, and 0.69, 0.29, and 0.11 MW for as working fluids. Remarkably, the energy locked in the NNW zone constitutes nearly 21% of the total geothermal energy potential within the entire dolomite horizons of the study area. The geothermal resources for the most perspective location within the dolomite horizon were estimated at 12.99 and 1.09 MW levels, using water and as working fluids, respectively, assuming 50 years of the project’s lifetime.Krakówwersja wydawnicz
Mining - Informatics, Automation and Electrical Engineering
No full textZ uwagi na zmiany klimatyczne coraz częściej poruszane są zagadnienia dotyczące gazów cieplarnianych i ich emisji. Metan, obok dwutlenku węgla, uznawany jest za jeden z najistotniejszych gazów cieplarnianych, którego ograniczenie emisji może przynieść w krótkim czasie zauważalne korzyści dla środowiska. Emisje antropogeniczne stanowią około 60 całkowitej emisji metanu, stąd też to właśnie w tym obszarze najczęściej poszukiwane są rozwiązania ograniczające emisje tego gazu. Przedmiotem opracowania jest system ujęcia metanu w kopalni „Pniówek” należącej do Górnośląskiego Zagłębia Węglowego (południowa Polska) oraz możliwości zagospodarowania tego gazu za pomocą silników trójgeneracyjnych. W artykule omówiono możliwość wykorzystania metanu z kopalń węgla kamiennego w celu ograniczenia jego emisji do atmosfery oraz z uwagi na możliwość jego opłacalnego wykorzystania. Autorzy przedstawiają zastosowanie układu trójgeneracyjnego, w którym metan z kopalni jest spalany w silnikach gazowych i wykorzystywany do produkcji energii elektrycznej, cieplnej i chłodniczej. Pozwala to na zmniejszenie emisji metanu do atmosfery przy jednoczesnym zwiększeniu efektywności wykorzystania węgla. W artykule przedstawiono wyniki badań przeprowadzonych w kopalni węgla kamiennego w Polsce i na tym przykładzie wskazano na ekologiczne i ekonomiczne korzyści wynikające z zastosowania układu trójgeneracyjnego.Krakówwersja wydawnicz
Chemical Engineering Journal
No full textThe escalating global water crisis necessitates innovative approaches to developing sustainable water resources. Fog water collectors with variable surface wettability offer controlled fog harvesting in water-scarce regions. This study develops thermoresponsive fog collecting materials by electrospinning poly(N-isopropylacrylamide)-polyvinylidene fluoride (PNIPAm-PVDF) into yarns that are transformed into harp-like structures for enhanced water harvesting rate. Both meshes and harps using electrospun membranes exhibit the remarkable ability to transition between hydrophilic and hydrophobic wetting states at temperatures below the lower critical solution temperature (LCST). Hydrophilic and hydrophobic surfaces play distinct roles in fog water collection. Hydrophilic surfaces have a high affinity for water and enables droplet capture. Hydrophobic surfaces help the removal of aggregated water droplet and fog water collection. The highest water collection rate obtained with the electrospun PNIPAm-PVDF harp was 1415 ± 7.0 mg·cm−2 h−1. The water harvesting system based on the electrospun PNIPAm-PVDF harps exhibits a 485 % increase in water collection compared to the standard meshes made from the same material, emphasizing their potential for significantly improving the overall rate in fog water harvesting applications.wersja wydawnicz
Computer Science
No full textIn this paper, we attempt to generalize the ability to achieve quality inferences of survey data for a larger population through data augmentation and unification. Data augmentation techniques have proven effective in enhancing models’ performance by expanding the dataset’s size. We employ ML data augmentation, unification, and clustering techniques. First, we augment the limited survey data size using data augmentation technique(s). Second, we carry out data unification, followed by clustering for inferencing. We took two benchmark survey datasets to demonstrate the effectiveness of augmentation and unification. The first dataset contains information on aspiring student entrepreneurs’ characteristics, while the second dataset comprises survey data related to breast cancer. We compare the inferences drawn from the original survey data with those derived from the transformed data using the proposed scheme. The results of this study indicate that the machine learning approach, data augmentation with the unification of data followed by clustering, can be beneficial for generalizing the inferences drawn from the survey data.Krakówwersja wydawnicz
Mining - Informatics, Automation and Electrical Engineering
No full textHard coal mines are increasingly struggling with the widespread phenomenon of the decarbonization of the economies of European countries. As a result, they are forced to constantly look for opportunities to reduce unit mining costs. This is extremely difficult because producers of mining machinery and equipment are unwilling to incur high costs for the research and development of new products, as this industry is burdened with a high risk of unprofitability. This article describes one of the examples in which an attempt was made to reduce the costs of hard coal mining by modifying the method of controlling underground haulages consisting of belt conveyors in the Polish LW “Bogdanka” mine.Krakówwersja wydawnicz
Decision Making in Manufacturing and Services
No full textIn today’s dynamic technological environment, innovation plays a crucial role – especially for manufacturing enterprises that constantly strive to improve the quality of their products. This article examines the quality-management issue in a company producing car rims. It was identified that real-time quality control can sometimes be unreliable due to controller fatigue, leading to erroneous data interpretation or delayed responses to deviations in the production process. The study aimed to investigate the possibility of eliminating or significantly reducing these errors by employing a tool that is based on artificial intelligence. The article covers the preparation of training data, the training of classifiers, and the evaluation of their effectiveness in analyzing control charts in real time. The adopted hypothesis assumes that machine-learning classifiers can be effective methods of support for quality controllers. The research began with collecting measurement data from the machine and dividing it into training and test sets. The obtained results were evaluated using standard quality measures for machine-learning models. The results showed that the use of artificial intelligence can bring significant benefits in improving quality supervision in the production process of car rims.Krakówwersja wydawnicz
Decision Making in Manufacturing and Services
No full textChanges in the way market advantage is achieved and the emphasis on value creation that has been introduced by technological change are forcing companies to seek new and effective management tools when it comes to innovative activities, hence, the discussion and presentation of the conceptualization of such a decision-making model. Its basic premise is to take the technology life cycle as a determinant of the market diffusion of a product based on the use of new technologies. Consequently, a decision matrix is developed – one dimension of which is innovation measured by the dynamics of technical debt and the other by customer-perceived value. The product as an analytical object is considered as the sum of the utility functions while allowing for each utility function to originate from the use of a different technology (which is in an adequate phase of its life cycle). After presenting the theoretical model, an example of an analysis of a fictitious product is given, which is a device for cooling and printing food substances. The presented analysis example shows the practical possibilities of using the developed decision-making tool in the areas of the technological and marketing activities of the enterprise and, in particular, the design of new products or new utility functions.Krakówwersja wydawnicz