University of Miskolc OJS
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First results of the wavelet-analysis of karst water levels from the Bükk Mnts.
Get PDFDuring our research, we used long-term data measured by the Bükki Karst Water Level Monitoring System to subject them to a periodicity test based on statistical methods. The goal was to search for cyclic components in the data of karst water levels, water temperature and conductivity measurements, using the methodology of wavelet analysis to supplement traditional deterministic procedures. Based on the calculations, it was possible to detect several periods in the data series, we also detected several properties that are only characteristic of hot or cold karst wells. Cycles with a period of 1 year, 3 years, or even longer were detected at several measurement sites, and with the help of the method, we were also able to determine which cycles appeared in the time series, and whether there was a period when it was not detectable in the data series. During the wavelet coherence tests, we determined to what extent these cycles move together in the data series of the measuring points of the Bükk Mountains, and whether there is a case where one measuring point "leads" the other time series.During our research, we used long-term data measured by the Bükki Karst Water Level Monitoring System to subject them to a periodicity test based on statistical methods. The goal was to search for cyclic components in the data of karst water levels, water temperature and conductivity measurements, using the methodology of wavelet analysis to supplement traditional deterministic procedures. Based on the calculations, it was possible to detect several periods in the data series, we also detected several properties that are only characteristic of hot or cold karst wells. Cycles with a period of 1 year, 3 years, or even longer were detected at several measurement sites, and with the help of the method, we were also able to determine which cycles appeared in the time series, and whether there was a period when it was not detectable in the data series. During the wavelet coherence tests, we determined to what extent these cycles move together in the data series of the measuring points of the Bükk Mountains, and whether there is a case where one measuring point "leads" the other time series
Examining territorial inequalities in labour market processes in Hungary
Get PDFThe aim of the study is to examine labour market processes at the county level in Hungary, focusing on regional inequality. The territorial differences between Hungarian regions are not only noticeable in terms of income levels, but also in terms of labour market processes. The most commonly used methodology in the literature for measuring territorial inequality, the convergence calculation, was applied. The results are used to classify regions into clusters. The focus of the research period is the 2008 global economic crisis, but for more precise results, the 19-year research period (2000–2019) can be divided into three time periods. The results of the study show that there is some co-movement between labour market and catching-up processes. Highlighting the labour market processes, the absorptive effect of Budapest appears in the periods studied.The aim of the study is to examine labour market processes at the county level in Hungary, focusing on regional inequality. The territorial differences between Hungarian regions are not only noticeable in terms of income levels, but also in terms of labour market processes. The most commonly used methodology in the literature for measuring territorial inequality, the convergence calculation, was applied. The results are used to classify regions into clusters. The focus of the research period is the 2008 global economic crisis, but for more precise results, the 19-year research period (2000–2019) can be divided into three time periods. The results of the study show that there is some co-movement between labour market and catching-up processes. Highlighting the labour market processes, the absorptive effect of Budapest appears in the periods studied
Analysis of small plastic gears manufactured by SLS printing
Get PDFSelective laser sintering (SLS) is an additive manufacturing method. During the production, the equipment sinters powdered material and binds this material together to create a solid structure. SLS 3D printers use a laser as the power and heat source. During the manufacturing process, the laser is aimed automatically at points in space defined by the 3D model. Since in the past we have worked on the manufacturing of small plastic gears by other additive techniques (FDM, stereolithography) and on the determination of their accuracy, in this article we determined the same characteristics for the SLS process.Selective laser sintering (SLS) is an additive manufacturing method. During the production, the equipment sinters powdered material and binds this material together to create a solid structure. SLS 3D printers use a laser as the power and heat source. During the manufacturing process, the laser is aimed automatically at points in space defined by the 3D model. Since in the past we have worked on the manufacturing of small plastic gears by other additive techniques (FDM, stereolithography) and on the determination of their accuracy, in this article we determined the same characteristics for the SLS process
Electromechanical model of a hedge trimmer mechanism
Get PDFHedge trimmers are used for various applications, from lighter vegetations to tree-like plants. A key component of the hedge trimmer is the eccentric disk within its drive train, that can be looked at as a cam-follower mechanism. The eccentric is responsible for transforming the rotating motion into an alternating one. Another important thing about the eccentric is the acceleration it generates during the operation for the blades, this acceleration must be considered when considering the cutting force. With different eccentric profiles different acceleration can be achieved. This paper aims to create an electromechanical model for the drive train of a hedge trimmer and to examine the behavior of the system based on its variables.Hedge trimmers are used for various applications, from lighter vegetations to tree-like plants. A key component of the hedge trimmer is the eccentric disk within its drive train, that can be looked at as a cam-follower mechanism. The eccentric is responsible for transforming the rotating motion into an alternating one. Another important thing about the eccentric is the acceleration it generates during the operation for the blades, this acceleration must be considered when considering the cutting force. With different eccentric profiles different acceleration can be achieved. This paper aims to create an electromechanical model for the drive train of a hedge trimmer and to examine the behavior of the system based on its variables
Efficiency of machining polymer, marble and steel materials at abrasive water jet cutting
Get PDFIn recent decades, waterjet cutting technology has become widespread across various industries worldwide, ranging from automotive and insulation manufacturing to aerospace. Concurrently, it’s increasingly important for the applied technological parameters to be efficient and cost-effective. This necessitates the appropriate selection of key technological parameters. In this article, we examined the efficiency of abrasive waterjet cutting in three different material qualities: polymer, ceramic, and steel. The article explores the relationship between cutting depth—considered as one widely accepted indicator of efficiency—and technological parameters, drawing conclusions regarding the machinability of various materials.In recent decades, waterjet cutting technology has become widespread across various industries worldwide, ranging from automotive and insulation manufacturing to aerospace. Concurrently, it’s increasingly important for the applied technological parameters to be efficient and cost-effective. This necessitates the appropriate selection of key technological parameters. In this article, we examined the efficiency of abrasive waterjet cutting in three different material qualities: polymer, ceramic, and steel. The article explores the relationship between cutting depth—considered as one widely accepted indicator of efficiency—and technological parameters, drawing conclusions regarding the machinability of various materials
2D and 3D surface roughness parameters of surfaces machined by EDM
Get PDFIn electro discharge machining (EDM or spark erosion) the roughness of the machined surface plays a very important role in the applicability of the process. The EDM machined surfaces are near isotropic, so the 3D measured surface roughness parameters can be compared to the parameters measured by 2D method. This paper reports on the results of research on the comparison of 2D and 3D surface roughness parameters of EDM machined surfaces of tool steels. Based on the results of the performed cutting experiments and the subsequent measurements, conclusions will be drawn regarding the connection between the 2D and 3D surface parameters and the extent of roughness of steel surfaces machined by two type electrode material.In electro discharge machining (EDM or spark erosion) the roughness of the machined surface plays a very important role in the applicability of the process. The EDM machined surfaces are near isotropic, so the 3D measured surface roughness parameters can be compared to the parameters measured by 2D method. This paper reports on the results of research on the comparison of 2D and 3D surface roughness parameters of EDM machined surfaces of tool steels. Based on the results of the performed cutting experiments and the subsequent measurements, conclusions will be drawn regarding the connection between the 2D and 3D surface parameters and the extent of roughness of steel surfaces machined by two type electrode material
EGY TÖRVÉNYTISZTELŐ POLGÁR
Get PDFThe present study displays a part of the Hungarian jurisdiction in a groundbreaking way, from a practical point of view, through a specific, but very diverse case. Is there justice? What can a citizen in good faith do if the court awards his rightful claim in a protracted procedure, however, the decision cannot be enforced? Can we talk about equity? What is beyond the law?? These questions are investigated in the present paper.Jelen tanulmány formabontó módon, gyakorlati szempontból, egy konkrét, ám igen szerteágazó jogeseten keresztül mutatja be a magyar jogalkalmazás egy szeletét. Létezik-e iustizmord? Mit tehet a jóhiszemű állampolgár, ha a bíróság elhúzódó eljárásban ugyan, de megítéli a jogos követelését, ám ahhoz nem tud hozzájutni? Beszélhetünk-e méltányosságról? Mi van a jogon túl? Ezen kérdésekre keressük a választ a tanulmányban
Investigation of groundwater potential utilizing geospatial techniques in Owerri, Nigeria
Get PDFThis study used geospatial approaches to examine the potential of groundwater within the study area. Analytic Hierarchy Process (AHP) method was used combining various parameters including Rainfall (39.5%), Geology (23.5%), Slope (12.5%), Drainage Density (8.0%), LULC (6.1%), Lineament Density (5.4%), and Soil Type (5.0%) for an integrated geospatial analysis to assess the potential for groundwater in the study area. Pairwise comparisons were used to assess the relative importance of each parameter. AHP determined these weights after the pairwise matrices were completed. These weights show the relative importance of the themes when assessing the study area's potential for applications such as land-use planning or natural resource management. The AHP technique allows for the systematic evaluation and ranking of alternatives based on a variety of criteria. A groundwater potential index (GPI) map was created by combining all of these thematic maps and classifying the research area into three zones: poor (0.001 %), fair (41.092 %) good (58.686 %), and excellent (0.261 %) groundwater potential areas. The findings showed significant groundwater potential in regions with higher lineament density, low to average slope, and suitable land use and land cover. The weighted overlay strategy was reliable, according to the consistency ratio (CR) analysis of 0.043884. This work shows the importance of an integrated RS and GIS analysis for determining groundwater potential. The results help identify locations with higher groundwater potential and enable sustainable use of groundwater resources
Why failures in geotechnics are less frequent than predicted?
Get PDFOne of the most important unresolved problems in geotechnical risk assessment is that “Why are failures less frequent than our reliability studies predict?” In order to answer this question the safety requirements of Eurocode 7 have been investigated. It has been concluded that the safety of soil mechanics parameters, defined by probability requirements, does not included in the calculated Overall Factor of Safety, which represents the overall reliability of a geotechnical design. Method, how to convert the probability requirements to factor of safety is proposed. Incorporating the probabilistic safety of soil mechanics parameters into the Overall Factor of Safety results in a reliable estimation for the failure of geotechnical structures
Comparison of programing ANSYS and COSMOS/M finite element systems
Get PDFA simple optimization task is programmed by using the built- in programming possibilities of two finite element systems: ANSYS APDL (Parametric Design Language) and COSMOS/M built-in macro language. The same program is written in the two different programming language and the resulting program listings is compared. The demon-stration optimization problem is to find the minimum safe radius of an L-shape model, loaded by a uniform surface pressure. The program to solve this optimization task builds the model, solves the finite element problem, and iteratively improves the radius until the optimum solution. In both cases, when the program running ends, we will see the optimum structure on the screen, and we can use the menu possibilities of the finite element system to see any details of the optimized model or listing the values of the parameters