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The Analytical Hierarchy Process (AHP) is one of the multi-criteria methods with tools that are effective for decision-making in complementary or alternative medicine (CAM). This approach, in combination with other available methods, such as the Utrecht Method, allows medical professionals and patients themselves to take a balanced choice of special treatment and health control. This is particularly important for pregnant women who suffer from nausea and vomiting during pregnancy (NVP). The mechanisms of toxicosis occur, and the way of treatment have certain uncertainties. The decision-making process for therapeutic care must consider several factors, the determination of which is the result of collaboration between the patient and the healthcare provider. This paper presents the results of a decision-making study regarding the use of the ginger medicinal plant in helping a woman with NVP symptoms. The research was conducted using the original questionnaire according to the methodology proposed by the developers of the Utrecht Method. The chosen respondents were healthcare professionals with experience in treating NVP and pregnant women. The Analytical Hierarchy Process (AHP) capabilities in decision-making were shown in an example of analyzing the benefits, risks, and side effects of using ginger during pregnancy. The combination of two methodological approaches allowed to successfully connect the proven facts of using CAM therapy with the subjective assessment of all stakeholders. The study demonstrates that this approach successfully uses decision-making by structuring hierarchical decision elements and weighing the criteria involved in the decision-making issue. The article examines the practicality and effectiveness of using AHP when making decisions regarding the treatment and improvement of the condition of pregnant women with NVP, and summarizes the quantitative and qualitative indicators of the effectiveness of this method. The presented combination of two methodological approaches in decision-making allows for choosing an optimized medical strategy for supporting pregnant women through CAM therapy.

During energy transition, where sustainability and environmental protection are increasingly prioritized, ensuring safety in coal exploitation remains a critical issue, especially in the context of worker safety. This research focuses on predicting methane concentrations in underground mines, which is vital for both safety and operational efficiency. The article presents a methodology developed to predict methane concentrations at specific points in mine workings using artificial neural networks. The core of this methodology is a forecasting model that allows for the selection and adjustment of the neural network to the phenomenon being studied. This model, based on measurements of ventilation parameters, including methane concentrations in a given area, enables the prediction of gas concentrations at measurement points. The results indicate that with appropriate neural network selection and based on ventilation measurements, it is possible to forecast methane concentrations at acceptable levels in selected excavation points. The effectiveness of these forecasts depends on their timing and the input data to the model. The presented example of applying this methodology in a real mine working demonstrates its high efficiency. The best results were obtained for a 5 min forecast, with slightly less accuracy for longer times (10, 15, 30, and 60 min), though all results remained at an acceptable level. Therefore, it can be concluded that the developed methodology can be successfully applied in underground mining operations to forecast dangerous methane concentrations. Its implementation should improve mining efficiency by reducing instances of exceeding permissible methane concentrations and enhance occupational safety. [ABSTRACT FROM AUTHOR]

Until recently, horizontal-axial wind turbines with blades having a wing profile occupied a predominant position in the world wind energy market. But currently, vertical-axial wind units are of increasing interest and this is understandable from the point of view of their important features as: no requirements for the orientation of the wind turbine to the wind, the possibility of placing electrical and other equipment on the ground, no requirements for changes of blade chord installation angle along its length. The article discusses the aerodynamics of the vertical-axis wind turbines: the range of changes of angles of incoming flow attack on the blade, the dynamics of changes in the magnitude of the absolute speed of flow of the blade on a circular trajectory of its movement depending on the turbine rapidity, and also obtained in experiments interaction effect of the blades in the rotor. The experiments were carried out on wind turbines with original blades (basic version), which were designed to eliminate the shortcomings of low-speed rotors Savonius (low coefficient of use of wind energy) and high-speed rotors Darrieus (lack of self-start).

Polyurethanes are materials usable in wide spectrum of applications. This article is aimed at the properties tailoring of selected polymers by an alteration in initial materials. To achieve that goal, we proposed form the polyurethane matrix by mixing materials that have a different ratio of the initial components. Mathematical model has been developed that describes relationship of structure and strength, deformation, rheological and tribotechnical characteristics of linear block-polyurethanes based on oligoether blends. Oligoethers blend samples were obtained by injection moulding on an automatic thermoplastication machine with varying proportions of the starting components over the whole concentration range. A significant change of properties over the whole concentration range was observed and compositions with unique combination of characteristics have been determined. Obtained dependencies allow to predict the composition of the binary mixture with a tailored level of strength, deformation, rheological and tribotechnical characteristics. The obtained results are fully consistent with the practical experience of processing and exploitation of initial polyurethanes.

The tantalum carbide coatings were deposited on substrates made of 12Kh18N10T steel, ZhC6 alloy, and molybdenum by reduction of TaBr5 and CCl4 vapors with cadmium vapors at temperatures of 950–1000 K. The average deposition rate of coatings on molybdenum was ~5 μm/h, on ZhC6 alloy was ~6 μm/h, and on 12Kh18N10T steel was ~8 μm/h. The coatings were formed as columnar grains on the substrate surface and as a diffuse layer in the substrate material. The surface layers contained mainly tantalum monocarbide TaCy (y = 0.72–0.86) and a small fraction of tantalum. The coatings on the surface of ZhC6 alloy and 12Kh18N10T steel flaked off with increasing thickness, which was due to different thermal expansion of the coating and substrate, as well as concentration inhomogeneity and phase transitions in the substrate material during coating deposition and during the heating and cooling processes. [ABSTRACT FROM AUTHOR]

The probability of test object compliance with the specified requirements and non-binary decision is a measure of how likely the test object is to meet the criteria for acceptance or rejection based on multiple factors. It is necessary to calculate by using a valid mathematical model that takes into account the test object's characteristics, the test conditions, the test criteria, and the uncertainty of the measurements. The significance of the probability of test object compliance with the specified requirements and non-binary decision can help to evaluate the quality, reliability, and performance of the test object, as well as to support decision making in complex situations. [ABSTRACT FROM AUTHOR]

One of the most progressive technologies in foundry is die casting, where a significant part is formed by die casting of castings of a lower weight category. In the case of castings cast by pressure casting technology, one of the important quality indicators is the internal quality of the casting presented by internal defects. In addition to the alloy used, the shape of the mold and the filling chamber also affect casting defects. Casting parameters such as pressure and speed significantly affect the quality of the resulting casting. The resulting homogeneity of the castings is very important in terms of mechanical properties. [ABSTRACT FROM AUTHOR]

The main aim of the presented research was to investigate the operational characteristics of a bearing when alternative lubricants were used for comparison with a standard lubricant, including that containing magnetic nanoparticles. The bearing was subjected to varying operating conditions, differing in terms of mechanical load status. The monitoring of the bearing operation parameters primarily focused on monitoring the velocity and acceleration of vibrations, as well as the operating temperature of the bearing. The bearing with lubricant doped by magnetic nanoparticles exhibited reduced vibration velocity and acceleration values both under no load conditions and when subjected to a mechanical load. The operating temperature slightly increased during testing in the case of the bearing with nanoparticles compared to the bearing using the original lubricant. [ABSTRACT FROM AUTHOR]

Advanced drilling technology makes it possible to penetrate oil and gas sites with deep bedding of oil reservoir, a complex multilayer structure and a high reservoir temperature at the well bottom, reaching 150°C. The difficult geology of oil strata leads to the fact that the productive layers of a well are flooded unevenly. In this work the causes for water cut in reservoirs are given, repair and insulation work and technologies for isolation of water-bearing intervals in the oil-producing wells considered. Grouting composites for water inflow limitation in reservoirs with low temperature (up to 100°C) and high-temperature reservoirs are studied. For water flood control in the oil and gas wells with high temperature viscoelastic composites with extended gel-time and high stable strength and adhesive properties has been proposed. The advantage of polymer-based composites is their kinetic behavior in dynamic mode, when filtering in a porous medium, which makes it possible to isolate effectively intake formations with different channel openings with a small flow rate of the mixture. [ABSTRACT FROM AUTHOR]

The paper focuses on experimental monitoring of tightening and floating of the belt at controlled loading of belt gear. In general, the belt gear is referred to as friction gear in practice the primary function of which is to transfer the performance as a consequence of frictional forces occurring between a driven belt pulley, a driving belt pulley and a flexible element. In experimental measurements, the flexible element is represented by a V-belt. The main advantages of the belt gears are peripheral speed, flexible engagement, silent running, vibration absorption and their price. Standard operation of the belt gear requires correct belt tightening which is achieved by movement of a pulley and a tension roll. At the same time, the belt tightening can be achieved by changing the spacing of the shaft axes used in experiments. In the case of belt gears use, specific principles must be observed. The principles include tightening of the belt with particular force which represents, in fact, primary condition of transmission of motion and force. At rest, the tension of both belt parts is identical. Complex analysis of belt gears was followed by experimental measurements on the stands designed for testing and monitoring of belt gears. For the purposes of monitoring of the belt floating there was a system designed which used a high precision sensor to measure distance between the belt and the sensor. At the same time, a device designed to determine the belt tightening was used as well. All measurements were analysed and collected data and facts were used to determine dependencies possible to be applied when the monitored parameters are evaluated. The results of experimental monitoring of the selected parameters at controlled loading of the belt gear can be useful in practice for designing, checking and maintenance operations. [ABSTRACT FROM AUTHOR]

The prospects for the use of polymer-polymer mixtures based on corn starch as alternative thermoplastic materials to polyolefins are considered. Rheological curves have been obtained, which confirm the possibility of processing such mixtures on standard equipment into products. It is shown that the starch content in polymer-polymer mixtures can reach 90 mass percent. Compared to existing biodegradable polymers, plasticized starch-based material is in no way inferior to them in terms of processability. Studies of the mechanical properties of polymerpolymer mixtures based on corn starch have been carried out. The data obtained indicate the possibility of using the developed composites as packaging materials, as well as alternative materials to known bioplastics and synthetic polymers. [ABSTRACT FROM AUTHOR]

One of the progressive production technologies through which it is possible to machine complicated shapes in materials characterized by high hardness is electrical discharge machining with a wire electrode. However, as with other progressive technologies, in the case of electrical discharge machining technology, demanding customer requirements for the geometric accuracy of the machined surface are not always met. These errors occur for various reasons. These are, for example, the vibrations of the wire tool electrode, its destruction during the machining process, the setting of technological and process parameters, but also errors in the design of the machine and the software control of the tool path. These and other errors have a primary role in the emergence of geometric inaccuracy of the machined surface after electrical discharge machining with a wire tool electrode. A special problem in the case of electrical discharge technology is the machining of internal and external cylindrical surfaces. As a result of the mentioned causes, deviations occur during their machining, which subsequently cause problems for the manufactured products during their assembly as well as the operation itself. Therefore, the objective of the experimental research was to identify the extent of these geometric deviations on the inner and outer cylindrical surfaces during electrical discharge machining with a wire tool electrode. [ABSTRACT FROM AUTHOR]

The paper describes the concept of improving the efficiency of the process of monitoring the technical condition and evaluating the service life of an asynchronous electric drive of promising trains based on the analysis of diagnostic information of various physical nature, taking into ac-count different types of diagnostic signals generated by individual drive elements and measured using vibration and current sensors. The implementation of the project provides an increase in the effectiveness of monitoring the technical condition of the electromechanical equipment of trains, allows to move from scheduled maintenance of high-speed rail transport to service according to the actual condition, to increase safety, as well as to the introduction automatic monitoring systems. Functional purpose of the system: monitoring the technical condition of electromechanical equipment and predicting the residual life of its nodes through the use of an intelligent decision-making unit based on a neural network. A scheme of hardware for data collection and analysis, an algorithm for collecting and processing data based on a registrar, and a predictive diagnostics algorithm have been developed. [ABSTRACT FROM AUTHOR]

In this study, the enablers of Customer Knowledge Management (CKM) software companies are investigated. Consequently, the conceptual CKM enabler model is developed by extracting "organizational", "technological" and "human" factors from the literature. Then, a Multi-Criteria Decision-Making (MCDM) approach is applied to identify the dependence relationships of factors by using the Analytic Network Processes (ANP) and the Decision-Making Trial and Evaluation Laboratory (DEMATEL) techniques. The inter-dependencies significance among the factors is evaluated by DEMATEL. ANP technique is used in order to clarify the relative significance of the factors and identify the weight and priority. The results show that the "organization" dimension is the most considerable aspect of enhancing CKM in software development. The "organization" aspect has more interaction with other aspects and activates the "technology" and "human" factors. In addition, "technology" is the second dimension that influences "human" and "organization". Due to the importance of CKM for organizations, this research provides a significant contribution in the context of CKM by extracting and ranking the CKM antecedent factors for enterprise software development context. [ABSTRACT FROM AUTHOR]

A procedure of standard strength tests of reinforcement bars conducted at present at the ITG KOMAG is discussed. Taking advantage of the bibliographic review, concerning tests of reinforced concrete with steel reinforcement bars, a possibility of using the KOMAG testing infrastructure to broaden the scope of tests of reinforcement bars was analyzed. Due to a more and more common use of composite bars for reinforcing and strengthening concrete structures, the methods of testing their strength properties are discussed. The conditions enabling to conduct strength tests of composite reinforced concrete bars at the ITG KOMAG are determined. [ABSTRACT FROM AUTHOR]

The article analyses the problem of measuring and examining the magnitudes of vibration amplitudes at the machining of materials by milling technology. By measuring the vibration parameter on the spindle head of a universal milling machine, the level of the vibration amplitudes magnitude during the milling process was acquired using a piezoelectric vibration sensor. The magnitudes of the vibration amplitudes were recorded during machining when the spindle speed varied between 1200 rpm and 1600 rpm. The measured values were evaluated in the form of FFT spectra, and the information required to design measures to avoid excess vibration amplitudes in such a case was obtained. [ABSTRACT FROM AUTHOR]

The application of cooling systems is a relatively efficient way to ensure the required thermal comfort conditions. One option is the application of cooled ceilings, where the heat load is removed using a ceiling structure with integrated cooling panels. These systems allow for a suitable way remove the heat load, but at the same time, compared to conventional air conditioning systems, they are characterized by a certain time dependence. The presented article describes experimental measurements carried out on days with high exterior heat exposure. Measurements evaluating the effect of the phase shift of temperature oscillations on the operation of the system were carried out using two cooling operating modes. According to results, it can be concluded that cooling systems based on cooling ceilings can be used effectively even with high external heat gains. [ABSTRACT FROM AUTHOR]

Sustainable development requires the research on new energy sources that will be safe and at the same time help to solve other societal problems. The paper is focusing on the analysing the heavy metals concentration of biomass and fuel mixtures of biomass and municipal solid waste. Analysis confirmed that the co-combustion of dirty fuels and biomass reduced the risk of releasing minerals and heavy metals from fuel into the natural environment. At a waste concentration of 20%, almost all heavy metals have passed from fuel to ash. Based on the experiment results and measurements, it can be stated that the co-combustion of biomass and municipal solid waste is a possible energy source that will significantly support sustainable energy development, but it is necessary to control the heavy metals concentrations during the whole process. [ABSTRACT FROM AUTHOR]

Virtual prototyping methods are an important aspect both in the designing process and in research processes aimed at the modification and optimization of machines and devices. It allows one to analyse the way of operation, the flow of forces, the cooperation between components, as well as finding the weakest points of the structure. This article presents the possibilities of using the MBS method, which is one of the tools used in virtual prototyping, on the basis of the results of R&D projects realized at the KOMAG Institute of Mining Technology. The main objective of the MBS method is to simulate the kinematics and dynamics of multi-body systems, the results of which will enable a series of analyses related to the operation of machines and devices. [ABSTRACT FROM AUTHOR]