Keresés

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  • Developing a Financial Sustainability Model of the Performance Indicators Applied by Jordan Water Company (Miyahuna)
    75-87
    Megtekintések száma:
    244

    Jordan is now facing real challenges to satisfy the current population water needs due to limited resources. Moreover, unfortunately, as a result of the increased demand for water in developing countries, water resources become scarce, thus, the sustainable management of water resources is very important everywhere and especially in these areas. The Ministry of Water and Irrigation in Jordan is aiming to improve both its quality of service and financial sustainability, therefore, it started to apply the performance measurement system developed by the International Water Association (IWA) to monitor its performance towards achieving these goals. In this article, a model connecting a financial sustainability indicator (operating cost coverage ratio) with other performance indicators applied by the ministry is developed. To assess the performance indicators and to build the model secondary data are collected from the targeted company, the data are analyzed using SPSS and Excel computer programs. Non-revenue water (NRW), speed of repair of bursts, and training per employee are found to be the indicators that have a major impact on Miyahuna’s financial sustainability, the NRW is found to have a negative relationship with the financial sustainability, whereas the other two indicators have a positive relationship. As a conclusion, reducing the NRW and increasing both the speed of repair and training per employee are recommended, by applying some methods that continuously diagnose problems in the water systems and defining clear and strict policies to control the water theft. Furthermore, using Active Leakage Control (ALC) methods, providing the needed equipment, tools and resources, and adopting new methods for training.

  • Economic Effect of the Coronavirus on the Companies Involved in Car and Automotive Parts Trading, and Manufacture of Tires of Hungary, Including Szabolcs-Szatmár-Bereg County, in Respect of 2020
    1-12
    Megtekintések száma:
    215

    In Hungary the wake of the first wave of the Covid-19 epidemic (March 2020), caused a decline in demand for goods and services in most sectors. There were sectors (accommodation services, art, recreation, etc.), which were economically severely burdened by the imposition of restrictive measures, and there were some (financial services, communication), which experienced the change positively. In our research, our goal was to assess the changes caused by the Covid-19 epidemic in the property, financial and profitability situation of the companies involved in car and automotive parts trading, and tire manufacturing, in Hungary, and within the country, in Szabolcs-Szatmár-Bereg county. We established three hypotheses: (1) As a result of the spread of coronavirus epidemic, in Hungary and in Szabolcs-Szatmár-Bereg county as well, the profitability of companies of NAICS codes 441 (car and automotive parts trading) and 4231 (wholesale of road vehicles and parts), decreased. (2) The outbreak of the epidemic had a negative impact on the liquidity of companies established in Hungary, including Szabolcs- Szatmár-Bereg county. (3) As a result of the Covid-19 epidemic, the resource structure of Szabolcs-Szatmár-Bereg county companies, analysed in the framework of research work, transformed. To prove or disprove these, secondary research was used. Finally, we put forward conclusions and proposals for the management of the companies active in this industry.

  • Design of Experiments Application for Machining Process Analyse
    257-265
    Megtekintések száma:
    112

    In this contribution are results from machining of the aluminium alloy by spiral router. The experiment was designed as full 3 - factors and 2-levels process and for evaluation of input factors to output parameters – Fx and Fy components were used Paret´s diagram and Lorentz´s line. The input parameters were: revolution speed (4000/min. and 6000/min.), working engagement of a cutting edge (depth of cut) ae (1 mm and 3 mm), back engagement of a cutting edge (with  of cut) ap (5 mm and 15 mm) and down (climb) milling.

  • Speed Variation along an Imposed Linear Trajectory, for Robotic Arms Motion
    495-502
    Megtekintések száma:
    66

    The paper describes a method of speed (velocity) computation, named mixt profile, during a motion upon an imposed linear trajectory. The method assures an accurate positioning at the end of motion (movement), in a well determinate time lapse. The described method is linked with position vector computation, about a robotic arm.

  • Investigation on Double Oxide Film Initiated Pore Formation in Aluminum Casting Alloys
    141-153
    Megtekintések száma:
    330

    The most common, and in fact, the most deleterious defects of aluminum casting alloys are the so-called double oxide films or bifilms, which have a central role in porosity formation, as they can easily unfurl and inflate into pores during the solidification of the alloys. Sr addition is generally used in the foundry industry for the modification of the eutectic Si phase of hypoeutectic Al-Si alloys. However, Sr microalloying usually leads to an increased pore formation tendency. As bifilms are preferred sites for pore formation, it should be expected that Sr additions have a significant effect on the number and/or the structure of double oxide films present in the melt. In this work, the relationship between Sr-concentration and the susceptibility to pore formation has been investigated through the evaluation of melt quality of melts which had different levels of Sr. The bifilm content of the melts was investigated by the analysis of K-mold specimens and X-ray computed tomography (CT) of reduced pressure test (RPT) samples. It was found that liquid alloys with a higher Sr concentration had a significantly greater tendency to pore formation, which can be explained by the presence of a larger number of bifilm defects in the liquid alloy.

  • Ultrasonic Powder Atomization for Additive Manufacturing
    69-75
    Megtekintések száma:
    158

    The following article presents a special case of metal powder production, ultrasonic metal atomization. In this case, ultrasound technology is based on the capillary wave phenomenon. We verify the suitability of the produced powders for 3D metal printing with various tests. In the case of prints with a metal powder bed fusion (PBF), the properties of the raw material of the powder are extremely important. The main results of the tests carried out in the article (SEM images, EDS composition analysis, sieve analysis) were described.

  • Efficiency of the Machining Process of Circular Shapes by Electrical Discharge Technology
    53-61
    Megtekintések száma:
    90

    Due to its high machining precision, EDM technology is nowadays very important in the production of high-precision parts for various industries. The high precision of the machined surface in combination with the ability to machine circular surfaces brings, in addition to several advantages, some negatives. The most significant negative of this machining technology is the relatively low productivity as well as the overall production efficiency. The latter is affected by many accompanying phenomena. The main accompanying phenomenon that contributes to the decline in the overall economic efficiency of EDM is the microgeometry errors that occur due to the non-homogeneity of the EDM process. Another accompanying negative phenomenon is the geometric accuracy errors of the machined surface, as a consequence of systematic destruction of the wire tool electrode, faulty interpolation in its guidance, and, last but not least, its vibration. These aspects consequently lead to the requirement for multiple applications of additional finishing cuts, which significantly reduces the overall economic efficiency of the machining process. Therefore, the experimental research aimed to search for options that can effectively help to achieve higher productivity but especially the overall economic efficiency of the machining process.

  • Investigating the Impact of Nature in Designing Cultural Environments for Children
    244-256
    Megtekintések száma:
    184

    There is a tendency to communicate with nature in human beings as a set of emotional experiences. This study investigates the impact of organic architecture in creating cultural spaces for children. The concepts of nature, naturalist architecture and children educational psychology, from the perspective of scholars and researchers in this area are investigated. The children’s perception of nature and their feelings were assessed and one hundred forty respondents among the instructors of cultural centres in different regions of Tehran have answered the questionnaires. To investigate the hypotheses, Univariate T - test and F - test were applied. The results showed that the stimulation of the natural environment has a positive and meaningful effect on curiosity, participation, and fantasy in children, while they show their impressions of nature indirectly. Therefore, designing applicable spaces according to children’s physics, using appropriate colours and furniture as well as more environmentally-related spaces, can have positive effects on social participation, intuitive and verbal skills of the children.

  • Adaptability of Powdered Activated Carbon Production from Ground Catering Waste Pyrolysis Coke
    162-171
    Megtekintések száma:
    120

    Three mixture of catering waste was pyrolyzed at 650, 725 and 900 °C and the solid residue (coke) was examined for powdered activated carbon production. For this, the carbon content, iodine number, particle size distribution and scanning electron microscopic images were analysed. Based on the carbon content, these cokes are suitable for activated carbon production, which were 60-85 wt.% (depending on the base material and pyrolysis temperature). The studied cokes showed slightly porous structure with smooth surfaces. Because of this, the iodine number was mostly small (13-30). Based on the grinding experiments, 10 minutes of grinding was found to be optimal. After this grinding time, the reached iodine number of powdered activated carbon was 350-610.

  • Surface Quality of Carbide Metal After Electrical Discharge Machining
    31-38
    Megtekintések száma:
    103

    Recently, the requirements for machining shape-complex products made of hard-to-machine materials, including carbide, have been increasing significantly. However, their machining is rather problematic. Additionally, a high-quality standard of the machined surface is generally required, not only in terms of roughness but also in terms of the geometric accuracy of the machined surface. All this while maintaining a high level of economy in the machining process. However, meeting these demanding requirements in real technical practice is not always an easy task. Moreover, in combination with modern machining processes, only a limited number of production technologies can meet this requirement. Therefore, due to the high demands placed on today's modern production and the required high standard of the machined surface, progressive EDM technology is increasingly finding its application. And it is through this progressive technology that it is possible to achieve relatively good success in carbide machining. The aim of this paper was therefore to describe in detail the results of an experimental investigation aimed at identifying the quality of the machined surface achieved in terms of the roughness parameters of the machined surface in the electrical discharge machining of selected types of carbides using a wire tool electrode.

  • The Impact of labor Turnover on The Service Quality of Hotels
    98-105
    Megtekintések száma:
    363

    This study aimed to know the dimensions of labor turnover (low morale, poor employees training, payment, job satisfaction) and study the effect of these dimensions on the quality of service in hotels. The results of multiple regression show that there is an effect of dimensions labor turnover on quality of service. Correlation between labor turnover and tangibility was the strongest and there is a moderate relationship between labor turnover and each of responsibility, reliability, assurance, and empathy.

  • Structural Investigation of Granular Composites by Modern Methods
    179-185
    Megtekintések száma:
    141

    Structural investigations of polymer-based particulate composites were carried out using modern test methods. We had composite sheets with different compositions and different injection molding speeds. In the polypropylene matrix, three types of glass beads were mixed in three weight percentages. In our investigations, the granular composites were studied with a widely used examination equipment, scanning electron microscope (SEM) and industrial computer tomography (CT) as a modern diagnostic tools. The purpose of the study was to investigate the distribution and interfacial adhesion of glass beads.

  • Present and Future of Industrial Robotisation
    1-12
    Megtekintések száma:
    70

    The following paper analyzing the installation of industrial robotisation in sectors and regions, in addition carry out forcastings on historical data. In recent years, automation and the use of industrial robotics have increased exponentially in the manufacturing sector. Given that companies prioritize enhanced production efficiency, quality assurance, and safety, it is evident that substantial investment and implementation of automation continue to occur in manufacturing facilities worldwide. The number of industrial robots globally has been growing steadily since 2010. However, the rate of growth has slowed from 2020 onwards. The impact of the Covid-19 epidemic was still felt in 2020, but the deployment of industrial robots increased significantly in 2021. Global industrial robot deployment is projected to continue to grow in the coming years, although the rate of increase may vary between regions and countries. The analysis showed a number of differences between regions in the number and growth rate of industrial robot deployments. Asia and Australia are the largest markets for robots and the number of robots deployed is expected to continue to grow in the future. Europe is the second largest market and, although growing at a slower rate, industrial robot deployment is also increasing steadily. In the Americas, growth is slower than in other regions, but still increasing. Global growth trends suggest that there will be further growth in the coming years and that the deployment of industrial robots will become more widespread in different parts of the world.

  • The Effect of Fluxes on the Melt Quality of AlSi7MgCu Alloy
    372-380
    Megtekintések száma:
    192

    The presence of inclusions such as oxides, carbides or refractory particles can be harmful to the mechanical and surface characteristics of castings. Inclusion-rich metals result in lower fluidity and feeding capability during casting. Nowadays, solid fluxes are widely used in foundries in order to reduce the inclusion content of aluminium melts. In this study, the effect of four different fluxes on the melt quality was studied. First, the inclusion content of the flux-treated melt, and then the properties of the fluxes (i.e. chemical composition and melting temperature) were examined.

  • Mixing Power Requirement Determination in Agitated Drum Using Dimensional Analysis
    76-88
    Megtekintések száma:
    134

    The mixing of granular materials in an agitated drum can be characterized by the dimensionless power equation. The equation was created by dimensional analysis, for which the parameters affecting the mixing power requirement were collected based on the literature. The most important of these are the rotational speed, the drum loading factor, the geometric and physical properties of the mixing drum and the granular materials.  The dimensionless power equation is used to estimate with reasonable accuracy the Power number within the given range of applicability , which has been validated by measurements. From the Power number, the mixing power requirement of the mixed granular material can be calculated, which can be used as operational data for selecting the mixing motor.

  • The Mechanical Properties of 3D Printed CuZn28 Brass Specimens with Different Orientations
    253-259
    Megtekintések száma:
    217

    In this paper, the properties of CuZn28 brass raw material were presented. The 3D printed metal specimens are made from this material with different orientations. Their mechanical properties (tensile strength, yield strength) and elongation were investigated according to MSZ EN 6892-1: 2012 standard. The strength of the different printing directions is analyzed and it is determined which printing direction is the most favourable. Finally, the effect of the different printing directions upon the structure of the material is studied.

  • Creativity and Innovation to Improve Processes in a Textile Industry
    80-96
    Megtekintések száma:
    142

    In this scientific work, the My Creative Idea (MIC) program was created and developed in the Coteminas S.A. textile industry, distributed among the organization's units in the country with emphasis on the São Gonçalo do Amarante unit in the state of Rio Grande do Norte. The aim was to critically analyze the improvements of industrial-scale processes resulting from the creativity and innovation intrinsically incorporated and experienced daily in the program. Thus, the general objective of the work was to evaluate the improvements in the productive processes coming from an innovation program in a textile industry, considering as specific propositions with respect to calculating the gains with reduction of losses, cost of implementation of ideas and measure financial returns and evaluate employee satisfaction according to the program. Moreover, there was free access in the company to be able to collect valuable information that could formalize a robust database for later structuring of the document, as well as the application of action research in the form of questionnaires. Therefore, the results verified clarified and emphasized the program's aggregating character to the organization in a general way under aspects that approach the financial spheres, the quality, and the satisfaction and motivation of the employees involved in this whole scenario. I suggest continuing to work on a continuous improvement methodology to further enhance My Creative Idea over the years, as well as insert this method of work to units that have not incorporated this program into their business strategies.

  • The Use of Partial Least Squares to define the Characteristics in the Environment of Higher Education Institutions and their Effects on Entrepreneurial Academic Education, a Case Study: Torreon, Mexico
    1-14.
    Megtekintések száma:
    81

    Because university incubators have a favorable effect on student’s entrepreneurial intents, Higher Education Institutions (HEIs) are essential to the delivery of entrepreneurship education. By analyzing the perceptions of students who received master diploma in management-business fields in Torreon, Mexico in 2021, the aim of the research is to identify the internal and external aspects of the HEI environment and their impact on entrepreneurial education using Partial Least Squares methodology with the help of the SmartPLS software, 156 responses from the statistical tool provided 120 responses. Three of the original hypotheses were confirmed, while four variables—two associated with HEI ecosystem external factors and two with entrepreneurial education elements—had to be removed since they were not accepted. The findings will lead to a better comprehension of the elements influencing master students' entrepreneurial perspective to create stronger relationship with elements of the HEI ecosystem.

  • Trends in Greenhouse Gas Emissions and Renewable Energy Policies in the EU and USA, with Special Emphasis on the Transportation Sector
    219-231
    Megtekintések száma:
    248

    The aim of this work is to review recent trends in the field of greenhouse gas (GHG) emissions and renewable energy policies of the European Union and the United States of America. During the last few decades, there was a significant shift within the political attitude towards these fields, therefore important changes were realized in the electricity production and the climate policy. In the present paper, we discuss the current situation focusing on the transportation segment.

  • Operational Feasibility Assessment of Geothermal Heat Harnessing Systems
    46-53
    Megtekintések száma:
    148

    Renewable energy sources are now essential to establish sustainable development. This paper examines one kind of source the geothermal energy. For geothermal energy when combined with a heat pump COP can be used for evaluation. For solely geothermal sources different approach is needed thus in the paper, a new geothermal heat production coefficient is used to examine the operational feasibility. For the assessment, many hypothetical buildings were created to model their heat demands. Two types of calculation methods are used for heat demand calculation. Based on the results, the maximum depth of a geothermal borehole and economically critical qualitative coefficient was concluded.

  • A családok pénzügyi helyzetének változása Magyarországon 2000-2019
    712-722
    Megtekintések száma:
    237

    Munkabérből élő családok pénzügyi helyzete számos tényező függvénye.  Meghatározza többek között a munkabér, a szociális támogatások, az adókulcsok alakulása, s az adható kedvezmények nagysága. Az adórendszer a magánszemélyek legnagyobb rétegét érintő részét minden évben, sőt évközben is változtatják, csökkentve ezzel a kiszámíthatóságot és az előre tervezhetőséget. Az elmúlt években az adóterhelés körüli viták során bebizonyosodott, hogy a személyi jövedelemadó kulcsát nem lehet a társadalombiztosítási járulékkulcstól elkülönítetten vizsgálni. A bruttó átlagkereset - a minimálbér illetve a garantált bérminimum emelése okán is - a vizsgált közel 20 év alatt több mint négyszeresére emelkedett. A nettó átlagkeresetnél a növekedés üteme ennél magasabb az adórendszerben történt változások miatt. A kötelezően meghatározott bér a vizsgált évek alatt majdnem közel hatszorosára emelkedett. De mennyivel lett kedvezőbb vagy kedvezőtlenebb a jövedelmi helyzete egy munkabérből élő átlagos családnak 20 év viszonylatában? A vizsgálatunk során arra keressük a választ, hogy a minimálbérek emelkedése, valamit a törvénymódosítások hatására a megélhetés milyen módon alakult.

  • Numerical Modelling and Simulation of Sheet Metal Forming Process
    1-6.
    Megtekintések száma:
    129

    Simulation and modelling of sheet metal forming process are well common today in different industries (automotive, aerospace) and several research centers regarding its huge impact for both on production and reliability of the lifecycle of the equipment, and the quality of the product. However, to obtain the best configuration possible with the inputs parameters to achieve high level of production and increasing the durability of the tools needs some extra methods for the optimization for this problem using mostly finite element method cooperated with iterative algorithms based on Artificial Neural Network (ANN) [1]. Whereas this research is focused on modelling of stamping process of stainless steel AISI 304 to investigate to formability of the material, and studying the influence of the friction factor on the quality of the product as well the energy required for each set configuration.

  • Optimizing the combustion processes of a small scale solid fuel-fired boiler
    358-369
    Megtekintések száma:
    133

    Over the last decade, the public has been paying increasing attention to reducing greenhouse gas and acid rain emissions and reducing particulate matter, which is extremely harmful to health and the environment. To improve air quality, the European Commission has achieved a range of measures to reduce air pollutant emissions in the transport, heat and electricity, industrial and agricultural sectors. In Hungary, the amount of gas and solid air pollutants from solid fuel combustion used by the public during the heating season represents a significant percentage of the total amount present in the atmosphere. In 2016, taking into the total emission, the 29% of CO2 emissions; 85% of CO emissions; 75% of the particulate matter emissions and 21% of the NOx emissions were derived from households. It follows that the improvement of air quality can also be achieved by controlling the emissions of solid fuel combustion plants. During our research we aimed to optimize the operation of a newly purchased TOTYA S18 boiler and a pilot pellet boiler. Operating the boilers in the correct mode minimizes air pollutant emissions, and the greater part of the heat generated is actually turns to heating the home, as with poor settings, a lot of heat leaves through the chimney. The data obtained during the tests can also be used to determine whether the boilers comply with the emission values set out in Commission Regulation (EU) 2015/1185.

  • Using the Photostress Method to Determine the Residual Stresses
    24-38
    Megtekintések száma:
    152

    Strains and stresses in loaded and photoelastically coated structural members can be determined using the PhotoStress method. The quantitative values of variations in the principal strains (stresses) and their directions could be employed to get the strain or stress components field on the entire coated surface. In the PhotoStress experiment, isochromatic fringes give qualitative and quantitative information. It provides a source of information on the directions and magnitudes of principal strain and principal normal stress on the surface of photoelastic coated parts. This article reviews the principle of using PhotoStress analysis to measure the residual stress and provides the boundary condition of using this method.

  • A COVID-19 pandémia hatása a munkavállalók fizikai aktivitására
    72-84
    Megtekintések száma:
    770

    A globalizáció, az elmúlt évek robbanásszerű technológia fejlődése jelentősen átalakította az emberek életvitelét, melynek következtében az ülő életmódot folytató emberek száma megemelkedett. A koronavírus világjárvány tovább tetézte a helyzetet és példa nélküli állapotot eredményezett a világban. A járvány kitörésével az otthoni munkavégzés jelensége egyre inkább elterjedt a világban, ami negatív hatással lehet a munkavállalók életmódjára, mely az üléssel töltött idő növekedéséhez és a fizikai aktivitás csökkenéséhez vezethet. Jelen kutatásban a koronavírus-járvány által okozott változásokat vizsgáljuk a felnőtt korú munkavállalók fizikai aktivitásában és ülő magatartásában. Online kérdőíves keresztmetszeti kutatásunk során hólabda módszertant alkalmaztunk. A felmérés célcsoportja a felnőtt munkavállalók voltak. 108 fő töltötte ki a kérdőívet, többségében (73,1%) nők, átlagéletkoruk 37,18 év és nagy részük magas végzettséggel (Diploma: 74%, PhD: 14%) rendelkezik. Összességében megállapítható, hogy a vizsgálatunkban résztvevő munkavállalók esetén csökkent a fizikai aktivitás és megnövekedett az üléssel töltött idő mértéke. Annak ellenére, hogy kevesebbet mozogtak a megkérdezettek, a járvány hatására, nőtt az online edzésen résztvevők aránya. A válaszadók többsége részben, vagy teljes egészben otthonról végezte a munkáját a járvány időszakában, mely tovább növelheti a mozgásszegény életmódot. A különböző területen dolgozók esetén nem találtunk szignifikáns különbségeket sem a sportolással, sem pedig a munkahelyi aktivitással kapcsolatos kérdésekben. A munkahely jó lehetőség a fizikai aktivitás ösztönzésére és az üléssel töltött idő csökkentésére a munkavállalók körében, ezért fontos, hogy a vállalkozások, a döntéshozók és az egészségügyi szakemberek olyan stratégiákat dolgozzanak ki, melyekkel ez a cél elérhető.

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