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  • Potentiodynamic Study of the Effects of Nickel on The Electrodeposition of Zinc from Chloride Media
    15-24
    Views:
    124

    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.

  • Long Container Dwell Time at Seaport Terminals: An Investigation Study from a Consignee Perspective
    Views:
    431

    Many companies are concerned about the problem of increasing average dwell time for their import containers at the port of the final destination and therefore incurring additional shipping costs in form of demurrage charges for the port administration and detention charges for the shipping line. Previous studies have addressed this topic by analyzing terminal operations and evaluated its effects on port productivity and competitiveness; however few studies have explicitly explored long container dwell time causes from a consignee perspective. This research aims to identify the causes of long dwell time for the import containers at port storage yards for one of the leading FMCG companies in Jordan. To that end, the data of import containers whose stay at the terminal exceeded the free storage days in the period between 2019 and 2020 were collected by referring to the set of shipping documents and reviewing the correspondences between the consignee and other parties in the supply chain. Based on the timelines that have been analyzed for each case of delay to the collection of shipping documents in consideration with the payment terms, as well as the clearance and delivery timelines, ten causes for the long container dwell time have been identified and classified into three main categories according to the types of flow in the supply chain; five causes related to information flow, two causes related to cash flow, and three causes related to physical flow. The impact of these causes has been evaluated using the demurrage and detention charges as a measure indicator and the findings of this research have also revealed that the causes related to cash flow have a greater impact than the other types of causes.

  • Current Challenges in the Regulation of CO2 Emission of Road Vehicles
    738-742
    Views:
    181

    Today, as part of the fight against climate change, regulations on greenhouse gas emissions are gaining significantly higher attention. Our work focuses on the European Union legislation on carbon dioxide emissions from road vehicles, with special emphasis on the target values. Current changes in CO2 measurement methods, as important issues of the regulations, are also reviewed within this article.

  • Dynamic Tests on a Series Wound DC Motor. Simulation of the Braking of the Vehicle Driven by the Motor
    15-20
    Views:
    86

    In the following we present the role and contribution of vehicle dynamics simulation to vehicle development in the University of Debrecen Faculty of Engineering. We present the input technical parameters which are necessary for the simulation of the series wound DC motor – which drives the vehicle – and also the procedure for their measurement together with the results of dynamic test measurements on the motor. The latest version of our vehicle dynamics simulation program –which is capable of the simulation of braking too – is also presented here.

  • Full-Scale Tests of Pipeline Girth Welds Under Complex Cyclic Internal Pressure and Static Bending Loading Conditions
    76-82
    Views:
    95

    The critical elements of high-pressure hydrocarbon transporting pipelines are often the girth welds, which are subjected to complex loads. The aims of our research and this paper are to introduce our full-scale pipeline fatigue and burst tests applying cyclic internal pressure and superimposed external bending stress on girth welds, furthermore, attracting the importance and the applicability of the investigation results. A unique testing system was built to study the behaviour of pipeline girth welds under simultaneous loads. The tests were evaluated using video camera recordings, internal pressure vs. burst time functions and failure pressure values.

  • Stationary and mobile particulate matter concentration measurement in Miskolc
    338-344
    Views:
    139

    A stationary and mobile device based on a low-cost dust sensor (Plantower PMS7003) was used to study particulate matter (PM) concentration in Miskolc. The stationary device was placed at the automatic monitoring station of the National Air Quality Measurement Network (OLM) in Martintelep, Miskolc. The mobile device was used to walk 4 streets along a square route with a total length of 800 m. Measurements were made on two days (September 9 and 11) between 7am and 9am, which according to preliminary experience coincided with the morning rush hour. The access route includes the OLM monitoring station, a busy road, two bypasses, a parking lot, and a smaller roadway blocked by traffic. The measured PM1, PM2.5, PM10 concentrations of the mobile device were interpolated on a circuit-by-circuit basis in ArcGIS, and conclusions were drawn for the area. The concentration of stationary and mobile devices was compared.

  • The Efficiency of Intellectual Capital as a Crucial Factor of Innovation
    419-428
    Views:
    244

    In today's global economy, there is a substantial shift from manufacturing to services, which challenges both economic policymakers, business stakeholders, owners, suppliers, competitors, and ordinary people: restructuring will encourage all economic players to learn how to adapt to new trends. That is why our research focuses on innovation and the ability of companies to create value. The IT sector is currently one of the fastest-growing and most innovative sectors within the service industry. The success of IT companies is greatly determined by their ability, how to make effective use of their intangible assets at their disposal, including intellectual capital, which is defined as a non-financial asset. So the question may arise: how is it possible to quantify and in monetary terms the intellectual capital of the companies to be examined? That is why, we calculated for the most successful Hungarian IT companies the widely recognized index, the VAICTM index, for which domestic calculations are not yet available. Indeed, this indicator eliminates the lack of information stemming from reporting standards by the methodology relying on publicly available financial reporting data. The indicator itself is a top indicator whose two main sub-indicators quantify the effectiveness of intellectual capital and physical capital.

  • Review on Construction Procedures of Driving Cycles
    266-285
    Views:
    278

    The goal of this paper is to give an overview of the literature of construction techniques of driving cycles. Our motivation for the overview is the future goal of constructing our own driving cycles for various types of vehicles and routes. This activity is part of a larger project focusing on determination of fuel and energy consumption by dynamic simulation of vehicles. Accordingly, the papers dealing with sample route determination, data collection and processing, driving cycle construction procedures, statistical evaluation of data are in our focus.

  • The Effect of annealing temperature on corrosion resistance and microstructure of Zr-Sn-Nb-Fe alloy
    420-424
    Views:
    115

    The Ti-2Al-2.5Zr titanium alloy plate in beta phase water quench at different times of the reentry after annealing is implemented while primary phase number and size distribution of samples are obtained. This research is carried out on corrosion behavior in 3.5% [mass fraction] NaCl solution. Experimental study showed that after the beta phase water quenching Ti-2Al-2.5Zr titanium alloyed after 500 oC annealing when partial recrystallization happened. There seems to be lots of tiny dispersion in the alloy that was annealed with its samples of six-party [HCP] structure of Ti, Zr, Al phase 2 with the dimension below 100 nm. Reaching 500 oC when the rate of annealing at a primary phase of the sample at 550 oC is low 90% of the primary phase is less than 100 nm. The changing of the rule of present decreasing also triggers little difference overall. Precipitation in the process of annealing Zr [Nb,Fe,Cr] 2is less that proves to be good for corrosion resistance.

  • The Role of Stocks in the Supply Chain
    515-526
    Views:
    1098

    Az ellátási lánc teljesítményét nagymértékben befolyásolja a szereplők készleteinek összetétele, nagysága, rendelkezésre állása. A végső fogyasztókért vívott versenyben kiemelt szerepe van a kiszolgálási színvonalnak, hiszen az ellátási láncok ugyanazokért a fogyasztókért vívnak versenyt, és a fogyasztók döntése leginkább e két tényező, mint a készlet nagyága és a kiszolgálás minőségétől függ. A tanulmány a kkv-k logisztikai problémáit feltáró kutatás része, melynek célja rávilágítani a jellemző nehézségekre, és azokra a kihívásokra, amelyek legtöbbször elkerülik a logisztikai- vagy ellátási lánc vezetők figyelmét. A fejlődő kkv méretű vállalkozások versenyképessége - ami magába foglalja a költségek nagyságát is, kapcsolódva a K+F tevékenységhez vagy vállalat növekedéshez – a lekötött tőke mértékével arányosan változhat, melynek jelentős részét képezik a készletek. A kutatásban résztvevő vállalat, a Diego Kereskedelmi Kft. készletezési politikáján keresztül kerül elemzésre a készletek összetétele, illetve a velük kapcsolatos kockázatok, illetve félreértések. A tanulmány célja továbbá a helyes megoldások elősegítése, melyhez szorosan kapcsolódik (az itt tárgyalásra nem kerülő) Lean megoldások támogató szerepe.

  • Neutral Inhomogeneity in Circular Cylinder Subjected to Axial Load on its Lateral Boundary
    35-42
    Views:
    141

    In this paper we consider the problem of single circular elastic inhomogeneity embedded within a circular cylinder whose curved boundary surface is subjected to surface traction acting on axial direction. We investigate the displacement neutrality of the coupled system of host body and inclusion. Neutral inhomogeneity (inclusion) does not disturb the displacement, strain and stress fields in the host body. The deformation of the considered inhomogenneous cylinder is antiplane shear deformation.

  • Development of Analysis of Loss Sources of Vehicles
    733-737
    Views:
    161

    Vehicle fuel consumption can be significantly influenced by various types of losses such as loss from bearing, aerodynamic drag and rolling drag. It is important to highlight that fuel consumption reduction can be only achieved when those losses are reduced that are induced during the operation.

    The aim of our work group is to define the calculation method and the magnitude of the losses of the vehicles. These parameters are intended to be serve as input parameters for future energetic modelling of vehicles.

  • Utilisation and Quality Management of Power Plant Fly Ash
    329-337
    Views:
    172

    Over the past decades, both the residential and industrial energy demand has increased due to the continuously growing consumption and production. As a large share of the electricity is still produced using fossil fuels, the utilisation of the by-products is a contemporary and pervasive issue. Fly ash is generated in large quantities in coal-fired power plants and has been proven to be an appropriate raw material for various industrial uses. Among others, it is applicable as an additive and lightweight aggregate in the cement and concrete industry, can be used for CO2 sequestration, glass foam production, catalyst production, or as a base material for geopolymers, as well. Geopolymers are inorganic polymers produced via the reaction between solid alumina and silica containing or alkali silicate materials in alkali media. Due to their numerous advantageous properties and wide variety of utilisation possibilities, research on fly ash base geopolymers became widespread topic. The quality of fly ash is determined by technical requirements, and the degree of quality control requirements depends on the final use. In certain fields of applications, standards and regulations have already been created to ensure the consistent quality of the final products made from fly ash, e.g. in the cement and concrete industry. There are various methods for fly ash processing, however, the methods to achieve the necessary properties are not standardised.

  • Investigation of the Luxury Yachts Condition and Their Maintenance
    95-105
    Views:
    147

    Surveying the condition of yachts and their maintenance is of great importance for their functionality and efficiency. Finding the right approaches, expertise at different levels, design benchmarking are essential for all yacht maintenance and security, resulting in crew and passenger safety. This report presents an evaluation and expertise in a real environment and documentation of decision-makers for the strength and functionality of a luxury motor yacht. For a good understanding of the problem, detailed photographic material has been documented showing in detail the required technical corrections. The research would be of interest to a wide range of yacht design and industry professionals, academic and research representatives, yacht users and all interested stakeholders.

  • Why do not people attend football matches in Hungary?
    11-22
    Views:
    265

    Both international and domestic research on passive sport consumption focuses on the motivations of fans. However in Hungary, unlike the examples of North America and Western Europe, we have to look for answers to the question of why people do not go to football matches. In order to find an answer to this question, we conducted an online survey with a number of items of 347 people. For the latter a scale measuring absence from sport consumption was used and the reliability of the scales was tested by Cronbach's alpha calculation. After our principal component analysis, we developed 5 internal and 5 external factors, on which we conduct hypothesis test along demographic and sports consumption variables. Based on our results, we have established that, contrary to public opinion, the low number of spectators in Hungarian football matches is not only and primarily due to unsucces and the low quality of matches. Our respondents are mostly kept away from stadiums by football-related government measures, as well as by preferring to participate in other recreational program opportunities.

  • Rotational molding of plasma treated polyethylene/short glass fiber composites
    103-108
    Views:
    154

    Rotational molding is a manufacturing technique for producing 3D hollow parts by adding plastic powder to a shell-like mold and rotating the mold while heating it with the powder. In contrary to the injection molding all the process operates at atmospheric pressure which makes reinforcement of the rotomolded product difficult. In this paper plasma treated PE and short glass fibers were dry mixed and used to produce composites by rotational molding process and characterized in terms of morphology and mechanical properties.

  • Perceived Barriers to Youth Entrepreneurship in Pakistan and Hungary
    382-391
    Views:
    127

    Entrepreneurship brings enormous benefits. It generates employment and helps in social and economic development. Ventures created through the youth entrepreneurship have enormous benefits. They generate employment, reduce poverty and unequitable distribution of wealth. These ventures do also help in social, economic and technological development. However, the youth faces several barriers to entrepreneurship. This study explores the personal & psychological, family related, institutional & regulatory, cultural & social, financial and market & knowledge barriers faced by the youth of Hungary and Pakistan. Qualitative research methodology was applied. Interviews at micro and meso levels were conducted from the young entrepreneurs and university professors of Pakistan and Hungary. Results indicate that Pakistan and Hungary have almost similar levels of Personal & Psychological barriers, however, the fear of failure is higher in Hungary than in Pakistan. Family related, cultural & social and market & knowledge barriers are higher in Pakistan for the youth entrepreneurship than Hungary. Institutional & regulatory and financial barriers are at medium levels in Pakistan. For Hungary, these are at low levels. The study has important implications for researchers, academicians, policy makers and for the young aspiring entrepreneurs.

  • Interchange of Heat in Saw Disc Body During Cutting
    488-494
    Views:
    112

    The paper presents the experimental results of a research aimed at the distribution of the temperature on the circular saw blade body. The temperature was measured at two distances from the centre of the circular saw blade body (70 mm, 140 mm) by means of an infrared thermometer. Two circular saw blades with the diameter of 350 mm and a variable adjustment of the body (with slots and without the coating, with both slots and coating) were used for the longitudinal sawing of the spruce wood (Picea excelsa) with the thickness of h = 37 mm. Feed speeds ware vf1 = 14 mpm, vf2 = 17 mpm and vf3 = 20 mpm. Cutting revolutions n = 4100 /min. were constant. The measured temperature was in the range from 21 °C till 27 °C. The highest measured temperatures were recorded on the circular saw blade with the slots and coating.

  • A Debreceni Egyetem Gazdaságtudományi Karának Controlling és teljesítménymenedzsment szakirány kurzusainak értékelése
    100-107
    Views:
    494

    It is of major importance for the Faculty of Economics and Business of the University of Debrecen to become familiar with the opinion of students about the education carried out at the University, therefore particular attention is given to the feedback of students related to education. Measurement and evaluation/reviews serve multiple purposes. Students may – if explicit written consent of the lecturer is provided – get to know the opinion of their fellow students about each course, lecturers may receive feedback about the reputation of their courses, the University and Faculties may acquire information about the overall opinion of their students about the training. Feedback is basically suitable for supporting the work aimed at the improvement of training quality. In the scope of present study the reviews submitted by the students of the Controlling and performance specialisation within the Management and Organisation course are introduced.

  • Review of Drive Systems Applied in Modern Vehicles
    728-732
    Views:
    165

    In this publication we review the drive systems of modern electric and hybrid vehicles. We also discuss the various types of electric motors, batteries, as well as fuel cell systems applied in them. Furthermore, as an important part of hybrid vehicles is the internal combustion engine, we review the literature about the methods used to.

  • Impact of Digitalization on Domestic Trade Strategies
    318-333
    Views:
    1386

    The aim of our study is to reveal the fit of digital space into current and future trade and to assess the effects of digitization on Hungarian trade strategies. The information gathering and purchasing habits of consumers have changed dramatically in recent years. Consumers today make buying decisions based primarily on convenience, effectiveness (fast and convenient access to products at adequate price/value ratio), and experience. Adjusting to these trends, traders developed novel trading strategies, and the use of achievements of digitization is an integral part of these strategies. One aspect of digitization is the increasing global development of e-commerce. The Hungarian online commerce have also been expanding significantly from year after year: based on 2018 data, domestic and foreign online sales volume have passed 1000 billion HUF. The Hungarian online consumers buy on the Internet more and more often and at greater and greater value. The online shopping on virtual reality platforms may make this purchase mode more experiential. Webshops have to meet new consumer needs, and deliver the ordered products as soon as possible, preferably within 24 hours. An increasing number of parcel delivery options has begun becoming more and more popular (e.g., automatic parcel terminals, pick pack points). However, traditional channels should not be buried, either. Their obvious advantage is that consumers can take their choice based on multiple senses and it also gives them more room for impulse buying. Combined with the digital technology compliant with contemporary requirements, this can offer a complete shopping experience. Nowadays, recognizing this need online and traditional channels have been mixed in several cases (e.g., multichannel, omnichannel, cross-channel sales) and offer several options for consumers during the purchase process. The sales area optimization of traditional shops and the buyer paths aided by digital technology (e.g., digital shelf labels) are designed for the buyers’ convenience. The newest innovations imply automation of the buying process making the whole process more convenient and more personalized with the use of sensors (e.g., Amazon Go) or robots (e.g., Pepper). In our future purchases, digital personal assistants will appear as digital versions of sales personnel.

  • Introduction to Design and Analysis of Torsional Vibration Dampers in Vehicle Industry
    310-324
    Views:
    318

    The crankshaft of today’s internal combustion engines with high performance output are exposed to harmful torsional oscillations originated from the unbalanced gas and inertial forces. To avoid the fatigue damage of engine components, caused by the undesired vibrations, torsional vibration dampers can be applied. Viscodampers are one type of the torsional vibration dampers, which operational fluid is silicone oil. For cost-effective R&D activities and production, finite element and finite volume numerical discretization methods based calculation techniques must be involved into the engineering work supported by the modern computer technology. The aim of this paper is to provide an insight into the multidisciplinary design and development process of visco-dampers in vehicle industry applications. Four different examples as structural, fatigue, CFD analyses and structural optimization have been introduced in the present work. It turned out from the static structural and fatigue analyses, that the investigated damper has safety factor over the limit for both static structural and fatigue analyses, so it is suitable for the given load conditions. In the structural optimization process 34.36% mass reduction has been achieved. According to the coupled fluid dynamic and heat transfer simulations a rather stagnating air zone evolved between the engine and the damper during the operation, which can cause efficiency reduction of cooling fins mounted onto the housing. In light of the numerical results, the suitable damper position has been determined for the highest heat transfer.

  • HAZ Characterization of Automotive DP Steels by Physical Simulation
    478-487
    Views:
    167

    DP steels were extensively used in the vehicles industry due to its extraordinary combined properties of strength, ductility, formability and weldability which contributed great significance in reducing strength to weight ratio and CO2 emission. High strength steel i.e. DP steels (3 different grades) were experimentally investigated and thermophysically simulated using Gleeble 3500 simulator to determine softening and hardening in heat affected zone. Samples were heated to different peak temperatures (1350 °C, 950 °C, 775 °C and 650 °C), two cooling time (t8.5/5 = 5 s and 30 s) and Rykalin 2D model were selected. The hardness and microstructure of the specimens were tested and analysed. For longer cooling time (t8.5/5= 30 s), we observed that softening occurs in all grade of investigated DP steels to all sub-regions. But for shorter cooling time i.e. t8.5/5= 5 s the softening is higher in intercritical HAZ compared to other sub-regions for all the types of DP steel with short cooling time (t8.5/5 = 5 s). However, the hardening zone in the CGHAZ occurs when Tmax is 1350 ºC for DP600, DP800 & DP1000 steels but it is more prominent in DP800 as compared to others two steel grade.

  • Polylactic Acid as a Potential Alternatives of Traditional Plastic Packagings in Food Industry
    123-129
    Views:
    336

    Huge quantity of synthetic polymers is used as packaging materials in different fields of food industries. A significant part of these polymers applied as a primary, direct food contact construction. The scoped application area is the sweet industry. In this field Polystyrol (PS), Polypropylene (PP) and Polyethylene terephthalate (PET) have used but during the last fifteen years the usage of PET has been grown. In one hand the price of this material is efficient, form other hand the PET is the one of the most safe (for food industrial applications) petrol chemical plastic that can be used as primary or secondary food contact packaging material. To maximize the customer safety and minimize the environmental impact of traditional PET, a new bio-sourced and bio-degradable alternative polymer aimed to be used in this special food industrial segment. One of the potential alternatives is the Polylactic acid (PLA) that would be a possible substitute as it is compostable and produced from renewable sources and has good physical and mechanical properties [1].

  • Evaluation Opportunities tor Recreational Sport Services – Adapted to Higher Education Environment
    150-164
    Views:
    210

    In our study, we analyse various researches dealing with quality aspects of sport services, and different quality models related to the interpretation of quality. The results which were obtained in the framework of primary research activity present the opinions of students from five different research universities. Sport services’ operation and sustainability are determined by market regulations, as parts of the service industry. Considering that the university leisure sports services take place in a competitive environment, the universities often have to compete with external sports service providers for achieving confidence of the young generations. For the qualitative tests, we used the QSport-14 measurement scale, which is generally applied by sports centres. This scale investigates the sports services according to three different aspects: (1) instructors, (2) infrastructural facilities and equipment and (3) offered sport programs. We have adapted the measurement scale to the university environment because of the differences and special characteristics of external sports service providers and university sports services. In addition, we analysed the factors influencing recreational sports, and we also examined that what changes would be needed in order to improve the quality of recreational sport activities in higher education.

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