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  • Rotational molding of plasma treated polyethylene/short glass fiber composites
    103-108
    Views:
    175

    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:
    134

    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.

  • Investigation of the Luxury Yachts Condition and Their Maintenance
    95-105
    Views:
    170

    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:
    291

    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.

  • Interchange of Heat in Saw Disc Body During Cutting
    488-494
    Views:
    121

    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:
    500

    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:
    194

    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:
    1414

    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:
    332

    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:
    184

    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:
    354

    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:
    226

    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.

  • Survey of the Dynamic Modeling Methods of Light Vehicles
    723-727
    Views:
    228

    Vehicle dynamics models can be classified into two groups based on the model simplification. There are simplified models based on neglections, these models do not contain all body directions: longitudinal, lateral and vertical directions. There are several reasons for the simplification: control, estimation and analysis methods can be used only with simplified models, or another reason is the computational cost. Apart from simplified models, there are detailed/truth vehicle dynamics models which aim is to provide a virtual plant of the real vehicle for virtual prototype-based development. In this paper, some simplified vehicle models are presented, after a short introduction.

  • The implementation of Balanced Scorecard System in social enterprises using the social-cooperatives – compliance with the needs of external organisations
    300-317
    Views:
    234

    To discover the major economic problems of social cooperatives, we have made a survey. The analysis of this survey stated that the quality of available labour force and the finding of the proper target markets are the biggest concerns of social cooperatives. By this survey a Balanced Scorecard model (BSC) was implemented, which is an adaptation of Bull’s model (Bull, 2006). Present paper demonstrates the BSC modul to satisfy the needs of external partners and authorities. These needs and the tracing indicators were determined, furthermore the frequency of the indicator measurement was also proposed.

  • Formation of Oxide Layers with Femtosecond Laser on Steel Surfaces for Color Marking
    174-178
    Views:
    211

    With the appearance of ultrashort pulse lasers, the researchers have begun working on various laser marking technology. Atmospheric heating and ablation of a surface induce laser coloration of metal surfaces. However, their application is still problematic today in the industry. With the appearance of femtosecond pulse lasers, a new concept became available for color marking. This concept is based on the formation of laser-induced periodic surface structures (LIPSS) on metal surfaces. The purpose of this article is to summarize the literature of laser color marking with ultrashort pulse lasers.

  • Improvement of High Strength Automotive Steels Wettability Properties Using CO2 Laser Surface Treatment
    422-427
    Views:
    163

    As a result of stricter environmental and safety standards, vehicle manufacturers have to reduce the weight of the vehicles, because 10% weight loss cause 8-10% reduction of fuel consumption. To reduce car’s weight and increase safety, vehicle manufacturers use high-strength steels. Further weight reduction can be achieved by using corresponding bonding technology (soldering, sticking) and optimizing these technologies can increase the strength of the joints. According to literature research, the improvement of interface properties has a large effect on bonding technologies. In order to improve interface properties, we can use multiple surface treatments. In our research we investigate the effects of CO2 laser surface treatment on high strength steels, because CO2 lasers are often used in the vehicle industry. In order to detect the effect of surface treatment, we investigate the wettability of the treated and untreated steels. In our research we measure the surface tension of treated and untreated steels. Our main goal is to improve wettability properties thus the bonding technology. In our research we used DP 600 high strength steel sheet with the thickness of 1 mm. We cut the steel sheet to 25mm wide and 55mm long workpieces. Before the surface treatment, the workpieces had to be cleaned and degreased using methanol. We searched for parameters that do not cause any visible changes on the surfaces. Among the parameters of the treatment we were able to change the output power of the laser. We used contact angle measurement to examine the wettability.

  • The Pressure Characteristics of the Released Gases from Sand Cores
    73-79
    Views:
    154

    The core packages used for the production of castings are generally made from cores of different quality (no- bake phenol, HB-phenol, and HB-furan) and resin quantity, to meet the various requirements for the casting. In our research, the effect of the amount of resin on the pressure of the gases evolved from the cores was investigated. Experiments have shown that increasing the amount of resin has a different effect on different binder systems.

  • Examination of Infrared Tomato Drying
    303-309
    Views:
    96

    Tomato is a highly perishable food, thus preservation is required to meet the continuous market demand compared to the unbalanced yearly production peak. The aim of this paper is to show a detailed insight into infraradiation based drying process. Furthermore, to widen the possible usage range of a well-known approximation method for describing the temporal moisture variation in function of process parameters. The mass decrease of tomato slices was examined, in function of specific radiation power, heat source and sample distance, in forced and natural airflow. Based on the results dimensionless moisture ratio change over time was fitted as an exponential function, which may be used in industrial drying process optimization.

  • Reduction of Energy Use for Heating in Detached Houses using Passive Technics
    64-76
    Views:
    141

    Reduction of energy use in buildings continue to be one of the most important goals in this sector. The aim of our research was to analyse the effects on the heating energy demand of passive technics. In the case of a detached house the energy savings using mass wall, Trombe-Michel wall and sunspace was determined. The calculations have been performed in the case of a building with average thermophysical characteristics and in the case of a building having similar geometry but its external building elements fulfilling the requirements of nearly zero energy buildings. It was proven, that some of the mentioned technics may lead to higher energy demand for heating, so a complex energy analysis has to be carried out before implementing them.

  • The Impact of Optical Character Recognition Artificial Intelligence on the Labour Market
    9-16
    Views:
    368

    Because of present day information technology, there is neither need to plant complicated computers for more millions price if we would like to process and store big amounts of data, nor modelling them. The microprocessors and CPUs produced nowadays by that kind of technology and calculating capacity could not have been imagined 10 years before. We can store, process and display more and more data. In addition to this level of data processing capacity, programs and applications using machine learning are also gaining ground. During machine learning, biologically inspired simulations are performed by using artificial neural networks to able to solve any kind of problems that can be solved by computers. The development of information technology is causing rapid and radical changes in technology, which require not only the digital adaptation of users, but also the adaptation of certain employment policy and labour market solutions. Artificial intelligence can fundamentally question individual labour law relations: in addition to reducing the living workforce, it forces new employee competencies. This is also indicated by the Supiot report published in 1998, the basic assumption of which was that the social and economic regulatory model on which labour law is based is in crisis.

  • The Impact of a Coronavirus Epidemic on China’s Public Debt Ratio Growth
    151-159
    Views:
    259

    Public opinion in the economic profession is strongly preoccupied with the expected negative economic effects of the coronavirus epidemic. Among the consequences, special attention is paid to the increase in the gross debt of the states. Indeed, based on conventional economic knowledge, it is clear to everyone that the economic downturn and the increase in government sector expenditure will directly lead to a sharp rise in government debt. The study aims to predict an increase in China’s government debt ratio using a macroeconomic model. The study will quantify the rate of increase in China’s public debt based on four theoretically possible scenarios for the course of the coronavirus epidemic. I am aware that it is difficult to apply conventional economic knowledge to China’s state-capitalist system. This is explained by the fact that the theories of the socialist economic model do not apply to China either. At the same time, the functioning of China's economy is closer to that of market-based economies, but the country's structure as a whole cannot be integrated into this framework either. But models describing the economic development of developing national economies cannot be applied to the country either. Nonetheless, I attempt to use conventional economic economics to attempt to quantify the impact of the coronavirus epidemic on China’s sovereign debt ratio. China’s public debt growth rates calculated under different outbreak scenarios are different, but none show an increase that would call into question the financing of China’s public debt.

  • Effect of the Changes in Bulk Density and Granulometric Properties on the Strength Properties of the Moulding Sand Mixtures
    116-122
    Views:
    183

    Foundry technology uses a lot of several natural materials. Sands use for preparing mixtures whereby making moulds or cores. Sand is defined as a granular, refractory major portion of mixture (90 – 98% in dependence on used binder). Sand properties depend on it has chemical and mineralogical composition; mainly particle size distribution and shape of grains and its size and sand surface texture. A comparative measurement of two quartz sand with different surface quality was carried out. Greensand mixtures were prepared to measure their permeability, compressive strength and wet tensile strength. The strength of sand mixtures has two main components. One of them is the cohesion of the binder; the other one is the adhesion between the binder and the foundry sand. The aim of this research is to determine the ratio of cohesion and adhesion within the strength values.

  • Development of a Small-Scale Plastic Recycling Technology and a Special Filament Product for 3D Printing
    365-371
    Views:
    354

    In our days, the fight against pollution has become a real challenge for the state. recycling is one of the solutions that is adopted in several nations to reduce the rate of plastic discarded in nature. The amount of plastic waste has been increasing for decades contributing to the environmental pollution that is one of the most serious problem of the mankind. according to the statistics not only the household plastic waste, but the industry discharge is increasing because the utilization of plastic as a raw material is more and more extending. plastic can be found in a lot of products, huge number of bottles, plastic bags, computers, auto parts are sold every day. The current applications for using recycled plastics in fabrication and design are fairly limited, on a small scale, plastics (such as abs, HDPe1, or Pe2t) are shredded and formed into pellets, and then either extruded into lament to be used in existing 3d printers, or injection molded into small parts and pieces of larger components. at a large scale, recycled HDpE is melted into sheets and either used directly as sheets in construction, or then heat formed from a sheet into components for construction. these methods of fabrication using recycled plastics are the norm because of their straightforward processes. nevertheless, each method leaves some complexity to be desired. This paper we study the types of plastics and diagnose the pollution caused by the latter. this allowed us to design and size a recycling station of plastic into filaments for three-dimensional printers. this station which will contribute to the fight against pollution. the station consists of two machines for grinding of the plastic and the other for the extrusion of the desired filaments. we were able to make a theoretical academic study on both machines and also we designed with solidworks 2015. The theoretical study is spread of the mechanical calculations necessary to the design and validation of the structure using the tools. as the prospect of this project, we want to complete the achievement of this station while completing the crusher and extruder mechanically. then switch to electric and electronic parts (introduction of engines, sensors and wiring...). In the case of waste plastics that are recyclable and reusable. the most widely used are polyethylene terephthalate (pet, used for synthetic fibers and water bottles), and second high-density polyethylene (hdpe, used for jugs, bottle caps, water pipes).

  • Kinematics and Control of a Planar Cable Robot
    88-95
    Views:
    134

    This paper deals with the kinematics and control of a planar cable robot [1], which is driven by four DC motors with gear. Cable robots are frequently used e.g., for the motion of cameras in sport halls and stadiums and also in high storage logistical systems [2]. Main goal of this research work is to design and build a test bench with low budget, which can model the motion of real life cable robots.

  • Egy világméretű sportesemény, a 2017 Vizes Világbajnokság néhány társadalmi aspektusa a jövő managereinek szemszögéből a felkészülési időszakban
    40-59
    Views:
    733

    Hungary hosts the 2017 FINA World Championships and Master’s Championships, one of the world’s largest sport event. Besides exploring the influential factors behind the potential effectivity, this study aims to identify social effects related to the event. Students in higher education today are the next generation of managers and company owners, therefore their attitudes and opinions will be determinative in terms of the decision-making. The empirical research took place in the University of Debrecen, the most populouses University of Hungary, 6 month before the official opening ceremony of the Championships.

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