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New method for the geometric design of the runner wheel of the Bánki turbine
Get PDFThis article is a continuation of a previous publication by Author. Paper (Hajdú, 2022) analyses the velocity relationships in the flow stream through the Bánki turbine. By exploring the velocity relationships, it is possible to determine the flow losses in the turbine runner and the runner efficiency of the runner. By implementing the theoretical results in practice, a new design procedure for the geometry of the runner of the Bánki turbine is developed
Hidrogén a dízelmotoros féktermi méréseknél
No full textIn 2012, a modern engine test cell was built at the Department of Fluid and Heat Engineering of the University of Miskolc for the load testing of diesel passenger cars and light commercial vehicle engines. The unique laboratory in the Miskolc area is capable of performing standard engine performance tests, as well as special durability tests, cycle tests, dynamic and cold tests, friction tests, and a wide range of environmental measurements and their impact on engine performance. Today, we aim to make the improvements identified by the various development trends. In the present research, we have investigated the possibilities of using hydrogen and diesel together in the engine testing laboratory. The investigations covered the legal issues of hydrogen storage and use in a closed laboratory environment. The results of this research will be used to plan further improvements in the laboratory.A Miskolci Egyetem Áramlás- és Hőtechnikai Gépek Intézeti Tanszékén 2012-ben modern motorvizsgáló cella épült dízelüzemű személygépkocsik terheléses vizsgálatára és könnyű haszongépjárművek motorjainak tesztelésére. Az egyedülálló laboratórium Miskolc térségében alkalmas standard motorteljesítmény-vizsgálatok elvégzésére, továbbá speciális futásteljesítmény-vizsgálatok, ciklusvizsgálatok, dinamikai és hidegvizsgálatok, súrlódási vizsgálatok elemzésre, valamint számos környezetvédelmi mérésre és a motor teljesítményére gyakorolt hatásuk vizsgálatára. Napjainkban a különböző fejlődési irányok által kijelölt fejlesztéseket kívánjuk megtenni. Jelen kutatás során megvizsgáltuk a hidrogén és dízel együttes használatának lehetőségeit a motorvizsgáló laborban. A vizsgálatok kiterjedtek a hidrogéntárolás és -alkalmazás jogi kérdéseire zárt laboratóriumi körülmények között. A kutatás eredményei alapján további fejlesztések tervezése következik a tanszéki laboratóriumban
Exploring the Impact of Informal Language on Sentiment Analysis Models for Social Media Text Using Convolutional Neural Networks
Get PDFThe present study sought to investigate the influence of informal language on the effectiveness of sentiment analysis models when applied to social media text. A Convolutional Neural Network (CNN) approach was employed, and the model was developed and trained on three distinct datasets: a sarcasm corpus, a sentiment corpus, and an emoticon corpus. The experimental design involved keeping the model architecture constant and training it on 80% of the data, followed by evaluating its performance on the remaining 20%. The results revealed that the model achieved a high accuracy of 96.47% on the sarcasm corpus, with class 1 exhibiting the lowest accuracy. The sentiment corpus yielded an accuracy of 95.28% for the model. The integration of the sarcasm and sentiment datasets resulted in a slight improvement in accuracy to 95.1%. The inclusion of the emoticon corpus had a marginal positive effect, resulting in an accuracy of 95.37%. These findings suggest that the use of informal language has minimal impact on the performance of sentiment analysis models applied to social media text. Furthermore, the incorporation of emoticon data may lead to a modest improvement in accuracy.The present study sought to investigate the influence of informal language on the effectiveness of sentiment analysis models when applied to social media text. A Convolutional Neural Network (CNN) approach was employed, and the model was developed and trained on three distinct datasets: a sarcasm corpus, a sentiment corpus, and an emoticon corpus. The experimental design involved keeping the model architecture constant and training it on 80% of the data, followed by evaluating its performance on the remaining 20%. The results revealed that the model achieved a high accuracy of 96.47% on the sarcasm corpus, with class 1 exhibiting the lowest accuracy. The sentiment corpus yielded an accuracy of 95.28% for the model. The integration of the sarcasm and sentiment datasets resulted in a slight improvement in accuracy to 95.1%. The inclusion of the emoticon corpus had a marginal positive effect, resulting in an accuracy of 95.37%. These findings suggest that the use of informal language has minimal impact on the performance of sentiment analysis models applied to social media text. Furthermore, the incorporation of emoticon data may lead to a modest improvement in accuracy
Elmozdulás és szögelfordulás szabályozása a rugalmas tartó-merev lemez alkotta mechanikai szerkezetnél
Get PDFThe present work will examine the effect of forces acting on a rigid flat plate connected to a flexible prismatic beam with the aim of clarifying what displacements and forces may occur during the contact between the end of the rigid pin connected to the plate and the body with a flat surface underneath. How do the different movement trajectories of the two known loading forces affect the movement and trajectory of the pin end, the magnitude of the frictional force between the pin and the lower body, and how much of a disturbing effect does this have on the final shape of the pin end trajectory. We examine several load variations, among others, we also determine a force movement path that will ensure the movement of the end of the pin in a circular path.Jelen munka a rugalmas prizmatikus tartóhoz csatlakozó merev síklapra ható erők hatását fogja vizsgálni azzal a céllal, hogy tisztázza a laphoz csatlakozó merev csap vége és az alatta lévő síkfelületű test között kialakuló érintkezésnél milyen elmozdulások és erők léphetnek fel. A két ismert nagyságú terhelőerő különböző vándorlási pályája, hogyan hat a csapvég mozgására, pályájára, a csap és az alsó test között fellépő súrlódóerő nagyságára, ennek pedig mekkora a zavaró hatása a csapvégi pályája végső formájára. Számos terhelési variációt vizsgálunk, többek között olyan erőmozgási pályát is meghatározunk, ami a csap végének körpályán történő mozgását fogja biztosítani
Measuring the pressure-flow characteristics of a proportional pilot operated pressure relief valve
Get PDFThe investigation of a pilot operated proportional pressure relief valve is described in this article. Different measurements are performed with a hydraulic test bench under laboratory conditions. A VT-VSPA1-1 amplifier module is used to control the current of the valve’s solenoid. The characteristics of the valve are determined as a function of the pressure – command value of the amplifier – volume flow rate. The results of the measurements can provide input data for the refinement of the mathematical model of the unit, which will be set up in the future.The investigation of a pilot operated proportional pressure relief valve is described in this article. Different measurements are performed with a hydraulic test bench under laboratory conditions. A VT-VSPA1-1 amplifier module is used to control the current of the valve’s solenoid. The characteristics of the valve are determined as a function of the pressure – command value of the amplifier – volume flow rate. The results of the measurements can provide input data for the refinement of the mathematical model of the unit, which will be set up in the future
Calculating the connection between precipitation and shallow groundwater
Get PDFFrom a water management point of view, it is particularly important to be able to examine the temporality of the precipitation that replenishes the shallow or even deeper groundwater layers. In our study, we use a method that allows us to analyze the evolution of both the precipitation and groundwater levels together. With cross-correlation and cross-spectral analyses, we can quantify the relationship between the two hydrological parameters for a given sample area, and the periods found in the relationship can also be detected. During our calculations, we were able to determine such delay times for a sample area in Debrecen using monthly and daily data series, so an 8-10 month and a shorter 3-4 day linear relationship between precipitation and groundwater was detected. Based on our results, several periodic components can also be found in this relation.
From a water management point of view, it is particularly important to be able to examine the temporality of the precipitation that replenishes the shallow or even deeper groundwater layers. In our study, we use a method that allows us to analyze the evolution of both the precipitation and groundwater levels together. With cross-correlation and cross-spectral analyses, we can quantify the relationship between the two hydrological parameters for a given sample area, and the periods found in the relationship can also be detected. During our calculations, we were able to determine such delay times for a sample area in Debrecen using monthly and daily data series, so an 8-10 month and a shorter 3-4 day linear relationship between precipitation and groundwater was detected. Based on our results, several periodic components can also be found in this elation
Hazardous area classification for wastewater treatment plants using by decree and standard
Get PDFIn the case of explosive technology, if there is a technological situation that has a fundamental impact on safety, there may be several possible solutions. This paper investigates this question at a biogas technology system of a wastewater treatment plant. The hazardous area classification of the plants in the exemplary wastewater treatment plant, based on the Decree 3/2009 (II.4.) of Ministry of Local Government on Technical Requirements for the Fire Protection of Installations using Renewable Energy Sources - Biogas, Bioethanol, Biodiesel and the MSZ EN IEC 60079-10-1:2021 Explosive atmospheres. Part 10-1: Classification of areas. Explosive gas atmospheres (IEC 60079-10-1:2020)".In the case of explosive technology, if there is a technological situation that has a fundamental impact on safety, there may be several possible solutions. This paper investigates this question at a biogas technology system of a wastewater treatment plant. The hazardous area classification of the plants in the exemplary wastewater treatment plant, based on the Decree 3/2009 (II.4.) of Ministry of Local Government on Technical Requirements for the Fire Protection of Installations using Renewable Energy Sources - Biogas, Bioethanol, Biodiesel and the MSZ EN IEC 60079-10-1:2021 Explosive atmospheres. Part 10-1: Classification of areas. Explosive gas atmospheres (IEC 60079-10-1:2020)"
Further steps in the digitalisation of tax law: Changes to the online invoicing system this year and planned rules on electronic vat and e-receipts
Get PDFThe digitalization of tax law has a decade-long history, the primary goal of which is to increase government revenues and reduce tax evasion. Several elements of this digitalization process are known: the online cash register, the Electronic Road Traffic Control System (EKÁER) system and the Online Invoicing System. My main objective is to prove how useful the state-of-the-art technological solutions that have been debuting in recent years are from the point of view of public finances, since, for example, VAT revenues have more than doubled.
In this study, I undertake to review the most important rules of the Online Invoicing System. After examining the legal background, I am processing a case brought before the Curia in which the plaintiff of the dispute was a VAT taxpayer who was unentitled to deduct tax, and the defendant was the Appeal Directorate of the National Tax and Customs Administration (NAV). Next, I will look at an Argentine procedure, electronic invoicing – e-Factura in Spanish – which has been optional on a voluntary basis since 2003 and has become mandatory for all taxpayers subject to VAT since 2016. The introduction of the new system was implemented in stages and was finally fully implemented by 2019.
At the end of the article, I discuss the changes affecting the Hungarian regulations in 2023, and then I present the revised rules of e-VAT and finally the e-receipt.The digitalization of tax law has a decade-long history, the primary goal of which is to increase government revenues and reduce tax evasion. Several elements of this digitalization process are known: the online cash register, the Electronic Road Traffic Control System (EKÁER) system and the Online Invoicing System. My main objective is to prove how useful the state-of-the-art technological solutions that have been debuting in recent years are from the point of view of public finances, since, for example, VAT revenues have more than doubled.
In this study, I undertake to review the most important rules of the Online Invoicing System. After examining the legal background, I am processing a case brought before the Curia in which the plaintiff of the dispute was a VAT taxpayer who was unentitled to deduct tax, and the defendant was the Appeal Directorate of the National Tax and Customs Administration (NAV). Next, I will look at an Argentine procedure, electronic invoicing – e-Factura in Spanish – which has been optional on a voluntary basis since 2003 and has become mandatory for all taxpayers subject to VAT since 2016. The introduction of the new system was implemented in stages and was finally fully implemented by 2019.
At the end of the article, I discuss the changes affecting the Hungarian regulations in 2023, and then I present the revised rules of e-VAT and finally the e-receipt
Comparison of human safety risks between old and new concrete mixing plant
Get PDFOne of, if not the most important service sector today is construction. It is constantly changing, both in terms of materials and workforce. That is why it is important to monitor it from a health and safety perspective. New materials, products and equipment are regularly introduced to the market, and it is essential not only to review them in advance, but also to monitor their continued use from a safety perspective. From the point of view of building materials, if we look only at the increased battery production and the construction of the halls required for this, reinforced concrete, of which thousands of m3 are produced every year, has an absolute advantage. The production of a simple reinforced concrete element is a very long process, from the raw material extracted to the delivery of the finished product to the construction site. In the 21st century, it has become clear to us that the future lies in robotisation and the constant introduction of electronics. The more machines, the more hazards. As in any other factory, the improvements in the plant under review are being made in parallel with the need to ensure safety at work. Newly installed and/or commissioned machines and equipment are subject to preliminary and periodic inspections and maintenance. This is no different for the concrete mixing plant of the company under investigation, which is constantly being improved and refined in order to develop the most efficient and safest production technologies. The aim of our work is to illustrate the new Italian-made concrete mixing plant installed when the existing mixer was replaced in the 1990s, and to show how this improvement and the use of modern technology have enabled the company to reduce the risks and make the plant safer from the point of view of health and safety.One of, if not the most important service sector today is construction. It is constantly changing, both in terms of materials and workforce. That is why it is important to monitor it from a health and safety perspective. New materials, products and equipment are regularly introduced to the market, and it is essential not only to review them in advance, but also to monitor their continued use from a safety perspective. From the point of view of building materials, if we look only at the increased battery production and the construction of the halls required for this, reinforced concrete, of which thousands of m3 are produced every year, has an absolute advantage. The production of a simple reinforced concrete element is a very long process, from the raw material extracted to the delivery of the finished product to the construction site. In the 21st century, it has become clear to us that the future lies in robotisation and the constant introduction of electronics. The more machines, the more hazards. As in any other factory, the improvements in the plant under review are being made in parallel with the need to ensure safety at work. Newly installed and/or commissioned machines and equipment are subject to preliminary and periodic inspections and maintenance. This is no different for the concrete mixing plant of the company under investigation, which is constantly being improved and refined in order to develop the most efficient and safest production technologies. The aim of our work is to illustrate the new Italian-made concrete mixing plant installed when the existing mixer was replaced in the 1990s, and to show how this improvement and the use of modern technology have enabled the company to reduce the risks and make the plant safer from the point of view of health and safety
Investigation and simulation of a scotch yoke mechanism
Get PDFThis paper studies the electromechanical model of a jigsaw mechanism. The jigsaw is powered by a battery, which drives a DC motor. The rotational motion is converted into linear motion through a Scotch Yoke mechanism. The electromechanical equations are based on energy approach using the Lagrange-equation. The Lagrange function contains the energies of the model, i.e., the kinetic co-energy of the kinematic chain and the magnetic co-energy of the inductance. As regard the non-conservative elements their virtual works are written. The formulated equations of the jigsaw model allow us to examine this force-energy relationship.This paper studies the electromechanical model of a jigsaw mechanism. The jigsaw is powered by a battery, which drives a DC motor. The rotational motion is converted into linear motion through a Scotch Yoke mechanism. The electromechanical equations are based on energy approach using the Lagrange-equation. The Lagrange function contains the energies of the model, i.e., the kinetic co-energy of the kinematic chain and the magnetic co-energy of the inductance. As regard the non-conservative elements their virtual works are written. The formulated equations of the jigsaw model allow us to examine this force-energy relationship