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  • Developing a Financial Sustainability Model of the Performance Indicators Applied by Jordan Water Company (Miyahuna)
    75-87
    Views:
    232

    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.

  • Parameter Estimation of Drag Coefficient and Rolling Resistance of Vehicles Based on GPS Speed Data
    109-115
    Views:
    131

    In this paper, a parameter estimation method of the model-based design approach is applied to estimate the drag coefficient and the rolling resistance coefficient of a vehicle. In fact, a constant-force parameter (c_const) and a velocity-square-force parameter (c_square) are in the vehicle model, and these result in the sum force applied along the translational DOF that models the vehicle. It is only an assumption that the constant force is the rolling resistance and the force proportional to the square of the velocity is the drag force of the air. Only GPS speed data is used for the estimation process. The conclusion is that parameter estimation is a good alternative when expensive measurement devices are not available to measure the force losses separately and directly.

  • The Measurement of The Three Components of The Cutting Force During The Turning Process
    139-146
    Views:
    96

    We carried out the measurement of the three components of the cutting force as a function of the modification of the depth of cut during the longitudinal turning process. The results show that if we increase the depth of cut, all three components of the cutting force shows increasing tendency, regardless of how much the cutting speed and feed speed were performed during the measurements [1] [2] [3] [4].

  • Design of Experiments Application for Machining Process Analyse
    257-265
    Views:
    99

    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
    Views:
    59

    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.

  • Potentiodynamic Study of the Effects of Nickel on The Electrodeposition of Zinc from Chloride Media
    15-24
    Views:
    104

    Abstract. The potentiodynamic experiments of the nickel effects on the zinc electrodeposition have been done to understand the impact of Ni impurities on the electrowinning of Zn from spent pickling liquor. The nickel chloride solutions of Ni concentrations 90 and 1 g/dm3 were used as the electrolytes. The latter was also mixed with 90 g/dm3 Zn in the experiments. All the runs were carried out at room temperature with 40 mV/s continuous polarization speed and with 1/s sampling rate. It was observed that nickel electrodeposition from chloride media containing 90 g/dm3 Ni started with the generation of hydrogen bubbles, entirely blocking the cathode surface. Only a slight current development was observed until the polarization potential ~ -0,8 V. The visual observation showed bubbles also formed at the anode, which may represent chlorine and/or oxygen evolution. While, in the electrodeposition of nickel with only 1 g/dm3 Ni concentration in the electrolyte, metal deposition was hardly observed, but visible hydrogen bubbles constantly blocked the cathode surface. A similar tendency was observed in the mixed-solution electrolysis cell; the initial tiny bubbles accumulated at the cathode surface more than in the pure Zn solution. The enhancement of H2 evolution indicates how nickel deposition may contribute to the loss of useful current in the process of Zn electrodeposition. The mass of nickel deposited from the mixed solutions significantly decreases as the Ni concentration decreases in the electrolyte, while the mass of deposited zinc is relatively constant. It means that the purity of the produced Zn is appreciably higher – with respect to Ni – if nickel is efficiently eliminated from the solution before electrowinning.

  • Analysis of Vibration During Turning Process of Different Materials
    200-205
    Views:
    105

    In this article, we would like to introduce the problems caused by vibrations in case of polymer turning processes. Nowadays there is a lot of research in this topic, to avoid the unnecessary phenomena of vibrations. The two most common methods are the Spindle Speed Variation (SSV), and the Vibration Assisted Machining (VAM). In case of SSV, the CNC machine can increase and decrease the speed of spindle continuously during turning which can significantly reduce the effects of chatter. This method is beneficial for longer workpieces when there is not any support except the chuck. Vibration-assisted machining can be used to minimise the problems caused by vibrations. VAM combines precision machining with small-amplitude tool vibration to improve the fabrication process. It has been applied to some processes ranging from turning, drilling to grinding. Based on the enumerated above we made some trial measurements about the basic vibrations of the turning tool shank. The tests were done on an NCT EUROturn-12B CNC machine which can found in the workshop of our institute. The tested material was Polyamide 6 because this is the most commonly used polymer in the industry. In the future, we would like to test some other basic and composite polymer materials too. The equipment was served by a specialist from SPM Budapest Kft. With these tests, our goal was to make sure that the equipment and the measuring setup are suitable for our future research.

  • Mixing Power Requirement Determination in Agitated Drum Using Dimensional Analysis
    76-88
    Views:
    114

    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.

  • Numerical Model Analysis of Myring–Savonius wind turbines
    180-185
    Views:
    156

    Nowadays the importance of renewable energy is growing, and the utilization of the low wind energy potential is getting crucial. There are turbines with low and high tip speed ratio. Turbines with low tip speed ratio such as the Savonius wind turbine can generate adequate amount of torque at low wind velocities. These types of turbines are also called drag machines. The geometry of the blade can greatly influence the efficiency of the device. With Computational Fluid Dynamics (CFD) method, several optimizations can be done before the production. In our paper the Savonius wind turbine blade geometry was based on the so-called Myring equation. The primary objective of this paper was to increase the power coefficient by modelling the effect of the wind on the turbine blade. For the sake of simplicity, a 2D cross-sectional area was investigated in the simulation with ANSYS CFX 19.1.

  • Derivation of ZF6HP26 Speed Transmission
    48-63
    Views:
    103

    Due to the increasing importance of automation, automatic transmissions have appeared. The different ratios of the transmission may be achieved by braking and coupling the corresponding elements of the planetary gear sets connected in series. The focus of the study is on the ZF6HP26 transmission. After disassembly and clarifying the teeth number of the gears, we derived the equations parametricly providing the ratios using the speed equations published in the literature. The ratio of each gear is calculated by substituting the particular teeth numbers into the derived equations. 

  • Development of Efficient Drive Based on Self-help
    147-151
    Views:
    70

    The efficiency and the life rating are essential characteristics of mechanical drives. The traction drives with proper geometry can avoid the geometrical slip and their efficiency can exceed that of the gear drives. The elements has hardened steel surfaces, the lubricant is rheopectic. There is no danger for thinning the oil film and consequently for connecting the asperities. The traction drives are relatively noiseless, they are applicable for increasing speed in particular. There are some problems to be solved in friction drive. This is the necessity of clamping force. A simple machine element usually make a constant clamping force, a tensioning mechanism can be too complicated. The ideal solution is a simple design which assure a clamping force that is proportional to the instantaneous external load requirements. The authors suggest a modified machine element – a helical torsion spring, an elastic one, instead of the original, rigid annular wheel – that comprises both the driving and clamping functions, and the latter one is proportional to the external load, so that the principle of self-help operates.

  • Sport Consumption, Fan Engagement, Sport Statistics – Post-specific Passing Characteristics in Football
    Views:
    607

    Digitalization and the explosive development of technology have led to significant changes in football. Due to the increasing amount of data available through various sensors and other data collections, we can observe the rise of data-centric, analytical and statistically oriented thinking in football, which is also of interest to fans. Digitalisation is also closely linked to sports consumption, which is why we have seen significant changes in this area in recent years. The pandemic has further amplified the speed of digital transformation in the sports industry. One of the most important contents for sports organizations and their fans is the in-depth sports statistics and analysis that enhances the consumer experience. In our study, we examined the most common performance indicator in football, passing. Our goal was to examine the position-specific pass characteristics in detail, therefore we also examined different pass properties in our research. As a model for our analysis, I chose the premier league, which has the highest UEFA coefficient. The three rounds (rounds 30-32) of the championship season 2019/2020 have been recorded and analyzed in terms of passes. there was a significant difference between the average number of passes per game between defensive and offensive players (t=7,988, p<0.05). There is also a gradual decrease in the number of passes attempted per match and the accuracy of the pass in the examination of the middle positions when examining the positions in the depth of the pitch. For both pass accuracy and average pass count, the decreasing ranking corresponds to the position of positions on the pitch (order: 1, central defender 2, defensive midfielder 3, inside midfielder 4, attacking midfielder 5, striker). In the value indicator of the position for passes, offensive positions performed more effectively than defensive positions. The extreme positions also stand out among the attacking positions, where in the case of the position value per pass number, 23.3% of the total test was completed and 14% of the amount of the established position value indicators was provided by these posts. Overall, our study points to post-specific pass characteristics and, knowing this, we can state that the comparison of players' passing performance is relevant if the players are in the same or related positions.

  • Changes in the financing of domestic research and development
    153-161
    Views:
    152

    Nowadays, the fourth industrial revolution is taking place at an incredible speed, with innovation at its heart. Of this, R & D funding is of paramount importance, which is directly or indirectly one of the most important tools for increasing corporate competitiveness. The study examines trends in domestic R & D expenditures over the past one and a half decades. It focuses on the extent to which the financial crisis has affected the amount of funding resources and their structure. From an international comparison, Hungary and the European Union spend much less on research and development than those in the global competition. The impact of the crisis is reflected in the decline in the growth dynamics of R & D expenditures, but it has not been solved solely as a result of the crisis. Changes in the domestic structure of expenditures in recent years are encouraging and are in sync with the change in attitude that is considered desirable in R & D funding. If we examine the domestic statistical data more thoroughly, we can no longer be very satisfied. However, from trends in data from recent years, it becomes apparent that neither Hungary nor the European Union will achieve the 1.8 and 3.0 per cent of GDP R & D spending by 2020.

  • The Role of Small-Scale Household Power Plants in the Electricity Supply by the Hungarian Settlements
    355-372
    Views:
    100

    The utilization of renewable energy sources spread with stormy speed on the world therefore more and more municipalities propose that they satisfy their energy demand from renewable sources. The fossil fuels represent a significant proportion in Hungarian energy balance and the majority of these is import energy. The proportion of renewable energy sources must be increased to decrease the energy dependence and the energy cost of municipalities, to increase the energy security and to consider the aspects of environment.The interest of Hungary is to increase the proportion of renewable energy sources in energy supply. In order  to this, the government created the small-scale household power plant (SSHPP) category in the Electricity law. This power plants should be not greater than 50 kW's performance. In this category, electricity can be produced from renewable and fossil sources. Since the government introduced the small, household size power plant category the installed capacity was grown quickly in the last seven years. The general capacity was 0.51 MW altogether at the end of year 2008 but it has already approached 129 MW’s at the end of year 2015. The general capacity was increased by the multiple of the previous year every year between 2008 and 2015 and there will be more a dynamic capacity expansion. Data about the capacity and the produced electricity can be displayed on municipality level, too. The purpose of the investigations is to determine: how can the built capacity of the small, household size power plant category participates in the electricity supply of the Hungarian settlements? So how many percentages of electricity demand can be gratified by this electricity power on the settlements? Based on this a ranking can be made among municipalities which shows the level of sufficiency in production of renewable energy and give a possibility for the power shift. Finally, to what extent can be built upon this power plant category in order to that Hungary can comply its objective value.

  • Investigation of the Resistance Force Acting on a Sailing Craft in the Case of a Change of Draft Caused by a Change of Powertrain Using Numerical CFD Simulations
    30-35
    Views:
    201

    Nowdays In the case of recreational craft, interfering with motor drive solutions is a common workflow due to increasingly strict rules for environmental reasons. When switching from an internal combustion engine to an electric engine, the change in draft varies from boat to boat, but it can be said in all cases that as the mass changes, so does the draft. Because of this, the magnitude of the resistance force acting on the ship also varies. In this paper, we examine, through a specific example, the benefits of a change in dive caused by weight gain at different travel speeds.

  • 3X3 Basketball Tournaments in Debrecen
    231-250
    Views:
    210

    Faster attacks, spin speed, increased adrenaline levels, vehement play. This is all about the 3X3 basketball. In Debrecen, the first 3X3 basketball matches were held in 2015, most of them did not even think that the sport would be popular in Hungary as well. Practically, from the start of the first minute, the games were played with great success. Following the successful settlement, the International Basketball Association immediately offered a 3-year contract to Debrecen. The purpose of our research was to examine the 3X3 basketball tournaments in Debrecen, which was analyzed using a questionnaire and an in-depth interview. 69% of the respondents participated in the 2016 and 2017 events, but only 37% attended the 3X3 basketball tournaments that were held for the first time in 2015. It can be stated that this trend is growing and the event is gaining popularity nationwide. Sponsors and sponsors covered every issue of the event so the event was free of charge over the years. 72% of fillers, however, are willing to spend money on a possible entry fee. In terms of revenue growth, the introduction of admission fees is unlikely to reduce interest. Up to 1200 seats have been filled up for the event every year. Therefore, it is not surprising that a lot of people would like to enjoy a higher auditorium with more space. The introduction of 4-point boundaries (3 points) for 3X3 matches would be a great opportunity to try the "little brother" of basketball in the 4-point so that it can be introduced in traditional basketball. Hungary became the pioneer of the sport due to the results of the Hungarian national team and the successful organization of sporting events.

  • Analysis of the Causes and Effects of Noise from Rail Transport
    116-130
    Views:
    56

    Noise emissions from rail transport are a major concern, as they affect both the environment and people's health and quality of life. Among the many sources of noise emissions, rail vehicles and infrastructure are a major factor. With regard to rail noise emissions, it can be concluded that noise effects are influenced by a number of factors. These factors include train speed, track condition, traction technology and the noise abatement methods used. The negative effects of noise exposure include sleep disturbance, stress and mental health deterioration. It also affects the quality of life of people in urban areas and property prices. It should be emphasised that reducing noise emissions from rail transport is key to creating a healthier and more sustainable urban environment. To achieve this, it is important to use modern noise abatement technologies, improve infrastructure and implement noise abatement actions effectively. Transport authorities and railway companies should work together to achieve a more noise-free rail transport, to improve people's quality of life and to protect the environment.

  • A Slurry-Pot Abrasive Wear Test Device for Several Composite Materials
    437-444
    Views:
    86

    To choose the proper material for agricultural machinery we tested several materials with abrasive cloth on the pin-on-plate test device. After having the pre-results, we launched more complex abrasive testing (slurry-pot) simulating more realistic mode with soils to investigate the abrasive wear mechanism and resistance of the selected up-to-date polymeric structural materials. for this, we developed a modified slurry-pot test machine that ensures the comparability of the materials over a wide range of conditions. Through this device, several parameters could be controlled like speed, the soil particle’s hit angle on the tested surface.

  • Practical Application of Methods in Strategy-Based Analyzes
    59-72
    Views:
    437

    Increasing environmental volatility is a growing challenge for companies and businesses. The speed of economic events is changing, and the risk of uncertainty is increasing, requiring business to take a new approach to strategic planning. In the design and forming of their strategy, both the factors of the external and internal environment and the analysis of their competitors can be based on well-chosen methods. We consider the review of these methods, their application in planning and educational practice. The aim of our work, in which we present the methods that underpin the strategy applied in both domestic and international practice. The analysis of the external environment illustrates the construction and applicability of an external factor analysis matrix based on traditional PEST analysis and the Porter's five-factor model. In the case of internal factor analysis matrix, we focus on the approach of method choice, and on the applicable methods, the importance of the resource-based approach, the analysis of key factors and the Porter value chain analysis matrix. The third pillar of the analysis that underpins the strategy is the matrix-based assessment of competitors. The applicability of the methods depends on the form of the enterprise, the field of activity and the nature of its activities, which is complicated by the emergence of new economic spheres (e.g.: sharing) and transformed power relations.

  • Wind Tunnel Making in Practise
    19-24
    Views:
    91

    In this paper, we examined the low speed wind-tunnels. Our goal is to construct an open flow system windtunnel that can be utilized in our measurements. To make such a wind-tunnel we needed to build a prototype and calibrated with the help of measurements. Than we determined the flow at the area of measurement. Finally results of the measurements satisfied our expectations. Although there is still much more in development that we would like to do based on the newly gained experience.

  • Vehicle Dynamic Simulation Possibilities Using AVL Cruise M
    309-323
    Views:
    163

    In most cases, when creating vehicle dynamics simulations, we need software that can speed up model creation and simulation. There are many programs on the market for this purpose, but they have different knowledge and user interfaces. We present in this article briefly introduces the use of one of the market's leading vehicle simulation software, the AVL Cruise M.

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