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Analysis of Thermal Degradation in the Annealing Process of Colored Parts Built by Extrusion-Based 3D Printing
124-133Views:488With the ever-increasing request of light materials, poly lactic (acid) PLA, have got much in consideration. Low-cost PLA materials have risen its use. Those possess some benefits but nevertheless insufficient mechanical strength. The printed PLA objects have a stumbling block for practical applications. Thus, annealing is an interested alternative to make 3D printed objects strong. This thermal treatment can significantly develop investigational studies and offer technical data. Hence the purpose of this paper is study and discuss how to increase the flexural strength through annealing process. Geometry distortions and color degradation will be analyzed. Differential Scanning Calorimetry, Taguchi Method (TM) and variance (ANOVA) were applied as part of the design experiments and analysis. Twenty-seven printed specimens were tested and factors as temperature, time and color were selected.
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Motivational Factors of Choosing BMX and Other Extreme Sports
426-441.Views:580Extreme sports play an increasingly important role in the supply of recreational activities, as an increased consumer demand has shown a dynamic growth over the past decades. In our research, we investigated motivational factors related to leisure time and in particular BMX sport on a sample of 237 people who do extreme sports. Our results have revealed that BMX is mostly chosen by young men as a leisure time activity. The consumers of extreme sports are characterized by internal motivation, pursuit of their own boundaries, testing of novel and exciting activities and the need for doing joint activities with acquaintances and friends.
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Visual Analysis and Geometric Modeling of Metal Foams
89-92Views:195The development of an efficient procedure for 3D modelling and finite element simulation of metal foams
is one of the greatest challenges to engineer researchers nowadays. Creating 3D CAD model is alone a demanding
engineering task due to its extremely complex geometry, and the proper finite element analysis process is still in the
center of the research. The aim of this project is to analyze the related literature and to adapt the results may be
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Menedzsment módszerek az Ipar 4.0 tükrében
507-514Views:825The fourth industrial revolution poses major challenges for organisations in terms of technological aspects and from a management point of view, too. Good (effective) management is vital as it can help overcome the difficulties arising from shortages of skilled labour and from cost-cutting pressures, and it can help improve efficiency of resources. Innovations require management methods that support the introduction of industry 4.0. In my review of the literature, I aim to find out how the current level of sophistication in this new field can help managers of SME to better embrace change. Based on the reviewed literature, from management point of view, organisational structure, leadership style and HR practices are key to creating an atmosphere conducive to learning and innovation. In terms of structure, researchers do not suggest one thing to apply, but emphasise that industry 4.0 is characterised by an unstable, changing environment, so it is worth developing a structure that is characterised by decentralisation, few rules, horizontal communication and collaborative teamwork, i.e. much more organic than mechanical. In terms of different leadership styles, it is the transformational leadership that is the most often mentioned, however, in case of industry 4.0, we need even more because it can have various limitations. Even before industry 4.0, literature has highlighted that the recommended leadership style can be defined as the combination of transformational and transactional leadership; research in industry 4.0 in recent years also emphasises that it is the expanded construction of a knowledge-driven leadership style that blends the two, which can best facilitate innovation and learning. Managers can develop employee skills and improve their learning abilities through a variety of HR practices. So the right structure, leadership style and HR prepare the organisation for industry 4.0 by facilitating learning, improving skills and innovation.
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Enhancing Sustainable Production Through Continuous Improvement: Evidence from Nigeria’s Manufacturing Sector
1-20Views:6The manufacturing industry in Nigeria has been the so-called cornerstone of economic development since the sector has continuously played a major role in providing jobs and industrial capital. However, there remain issues that impede its progress, including inefficient resource use, unstable regulatory systems, and the need to comply with international market requirements. Specifically, it examined the effect of employee engagement, process efficiency, and resource allocation on Nigeria’s manufacturing sector. A survey research design was adopted, with a total population of 117 employees across five manufacturing firms. A total of 91 participants were administered a structured questionnaire. Data collected was analyzed using PLS-SEM. Findings revealed that employee engagement has the strongest effect on sustainable production (β = 0.412, t = 6.250, p < 0.000), followed by resource allocation (β = 0.237, t = 3.610, p < 0.000), and process efficiency (β = 0.174, t = 2.877, p = 0.004). It concluded that continuous improvement is significantly vital for sustainable production in the five sugar manufacturing firms studied in Nigeria. It is therefore recommended that management of these selected firms focus on developing unique resource allocation strategies, employee engagement, and process efficiency to ensure sustained workforce improvement, thereby achieving sustainable production outcomes.
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The Effect of annealing temperature on corrosion resistance and microstructure of Zr-Sn-Nb-Fe alloy
420-424Views:222The 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.
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Business Students’ Attitude to Social Responsibility
1-10Views:377The companies’ most important goal is the satisfaction of consumers’ needs and the profitmaking. But nowadays the companies have to deal with the activity of corporate social responsibility, too. Therefore it can be interesting to research about the next questions: can ethics be taught? Do we have to teach ethics in the schools and especially in the business schools? What are the students’ attitudes toward the social responsibility? Are students sensitive and open-minded connection with this issues? The aims of the study were to examine responsible management attitudes among business students at the University of Debrecen (Faculty of Economics and Business). We draw their CSR pyramid (based on Carroll model) and present their opinion in reference to business education’s role in social issues.
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Vezetési stílusok egykor és most
1-16Views:3894The throughputs of Management sciences have always been in the middle of interest for its 105 years long history. Analysing the management styles is a prospering and actual scientific approach of leadership research. In the following, I present the throughputs of the researches which are applying this approach: I introduce both the „classical”management style models and the new ones. As for„classical”models, I introduce the decision-making oriented typologies, the personality oriented typologies and the situational leadership theories. By „new”theories I introduce the feminin and masculin management styles, the transactional and the transformational leadership and the participative management style. In the article I summarize the internal and external factors that influence the management style, and the same time introduce the outcomes of researches studying the topic.
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Servant, Ethical and Authentic Comparative Analysis of Leadership Styles in the Light of the Challenges of the BANI World
43-52Views:305In a globalised and accelerated economy, managers are under increasing pressure to reconcile organisational goals that are independent from human being with the reality of human relationships. The human being, as a being with intellect and senses striving towards happiness, is the focus of positive leadership styles and is their major concern in the field of management theory. In this article, three such positive styles, authentic, servant and ethical leadership principles and their operating conditions are compared using international literature. The literature time span of about two decades shows that the evolution of the ethical leadership literature has slowed down, while the authentic and servant leadership literature has continued to evolve and is still evolving today. The comparative table that appears in this study highlights both commonalities and distinctions, in that, in addition to high moral and ethical standards, the authentic style focuses primarily on the person of the leader, the ethical leader on the ethical standards of the organisation, while the servant leader focuses on the development of the well-being of the subordinate, the other person, even through self-sacrifice. We intend to use the results of this research to investigate measures of positive styles, preparing the scientific ground for future primary empirical field studies.
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Study of the University Electronic Games E-sports League and Its E-sports Players
52-61Views:272E-sports are competitive video games coordinated by different leagues and organisations. E-sports players belong to teams or different managements, which are sponsored by various economic companies and establishment. In the beginning, only offline and then online competitions were organised, and nowadays an offline final takes place in sports halls at the end of an online qualification round. The primary objective of the present research is to study the e-athletes participating in the University Electronic Games (UEG) e-sports competition. In addition to the e-sports players, I consider it important to examine the tournament itself, how the players interviewed rate it and what motivated them to participate again. I conducted an online questionnaire survey among the participants of the three seasons of the UEG online tournament organised by the University of Debrecen. UEG is the largest university e-sport tournament in Hungary in terms of its number of participants, which is why it was selected for the study. The participants in the study are motivated to compete in order to achieve success and enjoy competing to win, for them e-sports is a self-fulfilment. They keep up to date with national e-sports news and competitions through social media and the university mailing system. In general, the participants rate the UEG e-sports championship highly. The organisers need to improve the organisation of the tournament and their preparedness to run a tournament of this size. Their strengths are their helpfulness and their accurate and precise information about the tournament.
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Solid-Lattice Stem Optimization Design for Hip Implants
39-46Views:546The goal of this study is analyzed and design a methodology to reduce stem mass, through topology and lattice optimization of a Ti-6Al-4V hip implant, meeting yield stress requirements. Four optimization cases were studied: Topology optimization (1), Lattice design 100% (2), Lattice design 50% (3), Lattice design 25% (4). Five load cases from a study were applied for each optimization cases: Combined (LC1), standing-up (LC2), standing (LC3), going up stairs (LC4), jogging (LC5). The optimized cases design reduced stem mass approximately by 30% (1), 5% (2) ,8% (3) and 2% (4), compared with the total stem hip Ti-6Al-4V implant.
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Co-authorship Network Analysis
76-84Views:263The methodological basis of research on networks is given by graph theory. During the network analysis we work with a big data population and we are mainly analysing the relationships of the actors, which can be visualized with the graph network. The analysis of social network is becoming more and more popular in academic life as well. Most of the co-authorship networks are built around a number of prestigious people who manage their own network as a central player creating cliques.
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Millennium Generation Work Experience
657-665Views:336If we are open-minded in our everyday life, we should not overlook the phenomenon of student work. Within the framework of this study, our aim was to examine the work experience, later employment plans and income needs of students starting their studies at the Faculty of Economics at the University of Debrecen. In addition, we analyze the most important sources related to student work through literature studies.
It is important to pay attention to changing attitudes of newcomers to higher education as they become active job seekers after graduation. At the Faculty of Economics of the University of Debrecen, about 1,700 students started their studies in the 2019/2020 academic year. Our research was conducted with the involvement of these students.
The data were collected among students participating in the stork camp organized by the University of Debrecen. The survey covers, among other things, the initial salary requirements, previous work experience, future plans, including the willingness to work abroad, and factors that are taken into account when choosing a job.
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The Effect of Player Transfers on Football Companies Valuation
Views:443Transfer seasons are one of the most highlighted periods in world of football. The market of player rights forces the greatest european clubs with their enormous budgets to compete with each other in order to aquire the most talented and most succesful players. It is not uncommon to sign players for tens of millions of euros, to this extent these expenditures are seriously affecting clubs bottom line. However, despite the expenditure nature of player transfers the value of these clubs increase, based on the best known measurer for companies valuation: the stock exchange. In my research the effect of player transfers ont he valuation of football corporations are presented through market value development of stock market listed clubs namely Juventus and BVB Dortmund. Based on my results if the examined clubs were signing players according to a player transfer policy considered as succesful the value of examined clubs had increased through stock market price independently of player transfer balance. Moreover the effect of coronavirus could had been noticed, since both clubs valuation decreased heavily in the 2020 summer transfer window probably due to the revenue loss caused by the pandemic.
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Influence of MTP on Surface Roughness and Geometric Accuracy of Machined Surface at WEDM
91-97Views:257Electrical discharge machining technology is one of the most precise machining methods. Therefore, even the smallest deviation of micro and macro geometry generally has a significant impact on the overall quality of products produced by this progressive technology. The quality of the machined surface after Wire Electrical Discharge Machining (WEDM) is influenced by a large number of factors, most of which are influenced by the Main Technological Parameters (MTP). The aim of the paper was to describe the results of experimental research aimed at assessing the impact of MTP for WEDM on the quality of machined surface in terms of geometric accuracy and roughness parameters Ra and Rz. The samples were made of high alloyed ledeburitic chromium-molybdenum-vanadium steel designated EN X155CrVMo12-1 on a Sodick AQ535 electroerosion machine. The tool used was a standard compact brass wire 0.25 mm with the designation Elecut Brass CuZn37.
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Virtual Testing Method of Human Knee Prosthesis
386-392Views:243In the human knee joint, a degenerative wear of the joint can be formed, the common treatment of this disease is the total knee prosthesis geometry replacement and prosthesis implanting, the aim of our research is the study of the human knee joint with applications in prosthesis, we will develop a method by creating a virtual knee prosthesis geometries, we will generate the geometries using the ADAMS program and examined on a special knee prosthesis qualification equipment.
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The Information Security Risks of the BYOD
176-185Views:330Today we cannot imagine our everyday lives without using our smart devices. While commuting we often get into people - even literally - who are doing their work on their portable devices 24 hours a day. This habit is widespread; there are many solutions that can be used by the corporation to have their employees work on their private devices, besides using it in their personal life. They can use these devices at their home, while commuting, or even while being at their own cubicle at the firm. In this article, we are concentrating on the IT risks of the firm with this work practice from a theoretical point of view. After this step, we will continue our research with investigating the problem of measuring and mitigating of these risks.
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Sections of Hungarian Contemporary Architecture and Fine Arts
115-122Views:255In my study I have examined the sections of Hungarian contemporary architecture and fine arts. In the historical overview it has become clear that two turning points have influenced contemporary arts: the total art work (Gesamtkunstwerk) of the Ghotic and Baroque styles. I listed the sections in three categories: metamorphosis, relationship and section. The sections are the highest level of these categories. I explained my research in detail by analyzing these sections, at János Megyik's art and his Gate statue at Life Science building and library at the University of Debrecen.
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Comparative Study of Surface Treatment Procedures for Dental Implants
12-32Views:273Nowadays, the most common type of implant in dentistry is a partial tooth replacement, such as a crown, or a complete tooth replacement. Today, many manufacturers offer implants made of a wide variety of materials and designs. These restorations must meet strict standards, one of the most stringent being surface roughness. Since proper bone-to-implant contact only occurs with adequate surface roughness, several methods are used to achieve the correct value. After reviewing the results of experiments carried out by several research groups, it is concluded that the surface roughness, the shape of the implant fixation screw, the shape of the thread and the thread elevation used to achieve the desired roughness together determine the success of the implantation. The average surface roughness required for osseointegration is considered to be optimal for values between 1 and 100 µm. In most cases, the surface roughness of commercially available dental prostheses is Ra 1-2 µm, but this can be modified by various grinding, acid etching and polishing processes to suit the application. Acid etching is a common technique for roughness reduction, which is the most effective in reducing surface roughness of dental restorative materials (mostly titanium alloys), thus bringing the roughness within the desired range. The result of acid etching is influenced by the concentration of acid, the temperature of the acid bath and the time spent in the acid. The acid used for the surface treatment is important and is most commonly sulphuric acid, hydrochloric acid or hydrogen fluoride (HF) and combinations of these. The study shows that the most optimal results are obtained with HF. Replacements are nowadays largely made by additive manufacturing, which allows for customised replacements and, due to dimensional accuracy, reduces the time and cost of post-processing, i.e. the surface treatment can be used to achieve the desired surface roughness and size at the same time. As a result, newer materials are being used for clinical prostheses and surface treatment should be applicable to all materials. The most optimal solution is a combination of grit blasting and acid etching. With this technology, the surface roughness for all materials reaches the optimum value of 1-100 µm, sometimes 1-2 µm, but can be further reduced below 1 µm by polishing. The study investigates the role of surface roughness, the surface roughness should only be reduced up to a certain value, approximately 0.5 µm, as smooth surfaces have limited or no potential for osseointegration.
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Why do not people attend football matches in Hungary?
11-22Views:465Both 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.
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Examination of road sections in Debrecen by noise mapping
287-295Views:186During the research, noise level calculations were performed for 13 numbered roads in and around Debrecen and a noise map analysis was conducted on the roads’ environment. The first examined year was 1995, the last was 2017. In the time interval, annual status was determined based on average daily traffic data. In addition to the road noise values calculated for each section, a noise map was prepared for each survey year. For the evaluation of the results a difference map of the highlighted periods was prepared. Typically, noise level increase from road sources was identified between 1995 and 2017 in a significant part of the studied area (southern and eastern parts of Debrecen and around the newly built roads). Stagnant noise level was diagnosed near the downtown of Debrecen and around the main road No. 4, furthermore in some places noise reduction was caused by the development of the road network (between Debrecen-Józsa and Hajdúböszörmény, between Debrecen and Látókép around road No, 33, and along roads No. 4808 and No. 4814) .
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Material Stock and Flow Analysis within the Agricultural Building Sector Based on Local Database
297-320Views:249The purpose of the paper is to analyze on micro level the stream of building materials needed for raising cattle. The scope of the produced material flow chart will cover the inflow and storage of the materials. The overall objective of material flow analysis is to contribute to the data inventory development process which is needed to use these construction materials as secondary raw materials in the future. The assessment is based on a concrete new development in a Hungarian region being carried out nowadays as a development and modernization of an existing cattle raising farm. Driven by the concern of resource depletion, further research on higher level, based on larger database will be needed to verify the estimated national level results for the magnitude of growth of anthropogenic stocks.
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Quality Management System Requirements
168-179Views:481The quality management system requirements were changed in 2015. Organisations are granted a threeyear transition period after the revision has been published to migrate their quality management system to the new edition of the standard. The aim of this research is to analyze the differences between ISO 9001:2008 and ISO 9001:2015 requirements, and to identify that part of system elements which are not neccesary to change.
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Applicability of Optimization Methods in the Design of Automotive Rubber Products
358-363Views:248Size, shape or topology optimization are widely used to fulfil the requirements in the design process of rubber products. In many cases, the shape of the product is very complex and comes into contact with other components during operation. It is commonly subjected to large deformation for which the rubber shows strongly nonlinear behaviour. For this complex problem analytical solution is not available, thus finite element method could be used in which the analysis running is a time consuming process. The object of my research is to compare the efficiency and computational cost of different optimization algorithms. This article focuses on the applicability of various optimization methods in the field of automotive rubber goods. Direct search optimization and surrogate model optimization methods will be introduced.
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Examination of macro- and micro elements in the artificial bathwater samples
61-69Views:289During our research, micro- and macro element content of synthetically produced bathwater was examined. Previous studies, which were conducted at the Department of Environmental Engineering at the Faculty of Engineering, University of Debrecen, proved that the quality of domestic greywater is greatly varied. This diversity can also be observed in the case of greywaters. The examination of bathwater samples covered the contentanalysis of Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sr, Zn, Ca, K, Mg, Na, Li elements with the application of MP-AES method. The analysis of greywater’s micro and macro content is essential part in the control of irrigation systems, flushing as well as car washing, because its heavy metal content can have a significant effect on the environment. In this study, we would like to present the concentration values of micro and macro elements of the examined greywater samples. Furthermore, we would like to make a comparison among our result, previously examined greywater samples and drinking water samples, too.
