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Numerical Model Analysis of Natural Gas Combustion Burners
67-71Views:369Traditional power plants still the dominating power source for all the major industries and powerdemanding facilities, the most crucial facility for the whole plant operations is the industrial boiler which generatessteam, heating energy or electrical power. Boilers generate energy by combustion. The improvement of combustion efficiency could greatly influence the energy consumption and will make the boiler more efficient and cleaner (less emissions), that’s why it is important to understand the combustion and thermal flow behaviours inside the boiler. Beside experimental testing, computational work nowadays becoming more and more important due to lower cost and acceptable accuracy with minimum error. With numerical calculations method, the computational model created by a Computational Fluid Dynamics (CFD) software could reduce a lot of trial and error on experimental work. In this paper utilizing the ANSYS FLUENT 19.1 software to make crate the combustion model. The ratio of air to fuel mixture, the equivalency factor, mass flow rate of the mixture, velocity, mass fractions of the mixture components (fuel and air) and their temperatures will serve as the input parameter while the exhaust gase component mass fraction, temperature, mass flow and velocity will be monitored.
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Transaction Costs: A Conceptual Framework
131-139Views:1302Transaction Costs (TC) is a very important topic, especially in a changing work environment which has a large number of operational firms, and increasing business growth. The aim of this paper is to shed light on the transaction costs concept, and provide a conceptual framework to understand the meaning of transaction costs. Publications including articles and research papers have explained the notion of transaction costs and the theoretical issues related to them. The literature review reveals that, transaction costs are costs which arise because of the of a company‘s activities in the market , including (fees, commission, taxes) which are paid by the firm to provide a service or produce a good either to external parties or as internal costs. Therefore, according to the literature review. It emerges that firms must make a comparison between internal and external transaction costs and choose the lowest cost which enables them to increase profits. This means companies have to reduce transaction costs to the minimum level to achieve more profits and competitive advantage.
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The Expectations and Motivation Regarding Future Income and graduation of the Students of the University of Debrecen, Faculty of Engineering
1-11Views:288My research conducted among undergraduate students of the Faculty of Engineering of the University of Debrecen examined the students’ incentive and income expectation broken down by their gender and by their ducation level. At the same time, it aimed to measure the impact factors influencing their motivation to get the degree and their ideas regarding the payment.
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The New Type of Employment: the Specificity of the Platform Economy and Platform Work
75-90Views:846The industry value of the global platform economy exceeded 7 trillion US dollars by the end of the second decade of the 21st century. The income generated by the platform economy in the European Union produced an almost five-fold increase in the period between 2016-2020, as its volume increased from 3 billion euros to 14 billion euros. Nevertheless, due to the lack of global consensus and precedent, the delimitation of the platform business model and work, its legal regulation and verifiability and compliance, due to its innovative nature, are unresolved at the world and European level. The objective of the article is to define the conditions, rules and practical application of the platform economy and platform work, relying on international (English-language, mostly European) secondary information, thereby revealing the problems and difficulties, as well as discussing its advantages and disadvantages.
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Analysis of Social Media Activities - Through the Examination of Handball Clubs Competing at Different Levels
39-53Views:675In Hungary, handball enjoys special attention and support, this is true not only for our country, but also for Europe, and the sport is gaining more and more space worldwide. One of the biggest innovations of the last two decades is certainly social media, which has reformed the basic strategies related to information transfer and traditional marketing activities. The processes of content production on these platforms have radically changed, which every sports club should pay attention to, as they can gain significant advantages in terms of economics, marketing and community building if they are able to communicate well. Three sports clubs competing at different levels were compared during a qualitative study in terms of their social media marketing strategy activities, namely PICK Szeged, Balatonfüredi KSE – BFKA Balatonfüred and DEAC handball team. The basic concept of this research model was built on how the online marketing communication activities of club teams fighting for different professional goals at different levels differ from each other, as well as what are the development opportunities and aspects that can be used as effectively as possible on social media platforms. The handball club teams agreed on several research questions, but a significant difference could also be discovered in one area, in which the professionals responsible for social media disagreed or represented a different point of view. Looking at my results, it can be concluded that behind a successful online marketing strategy there is always serious preparation and planning work, as well as the diversification of content production on different platforms, because the consumer communities of the platforms are also different from each other.
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Presentation of Employment and Economic effects of the Covid-19 Epidemic between March and November 2020 among Companies Dealing with Car and Parts Trade in Szabolcs-Szatmár-Bereg County
80-92Views:703The outbreak of the COVID-19 pandemic during the spring of 2020 entailed major economic and social changes all over the world. In this study, we aim to investigate the impacts of the COVID-19 pandemic on the labor market and the economy with relation to the automotive industry in Szabolcs-Szatmár-Bereg County. Apart from secondary data collection, this research also relies on primary data collection methods, including self-administered questionnaires and in-depth interviews, all conducted with several employees and finance directors employed by the automotive companies present in the county. The focus of this research is to study how the pandemic affected the balance sheets and the gross revenue of these companies; how it altered the repayment obligation of their current loans and how it influenced their willingness to enter into new loan agreements or relief options offering financial assistance. Apart from these factors, this research also studies how the pandemic restrictions affected the work schedule and the benefits of the employees.
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Learning Curve Based Sigma Level Determination in Interrupted Non-Production Processes
260-270Views:289The philosophy and methods of six sigma process development have been applied successfully since mid1980s, and the application of the six sigma concept in non-production processes has increased significantly in the last decade. In this paper processes that can be characterized by learning curves are modeled. The quality of such processes can be analyzed on the basis of the six sigma concept. In this paper two back office processes are analyzed. The processes are built up of simple repeated steps and incorporate some interruptions. The application of the model allows the calculation of the maximally permitted number of interruptions in the process if the preliminary determined norm is to be kept.
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Concept Images of Primary School Students and University Students About Function
114-122Views:466The concept of function is fundamental importance to the mathematics. Since the most mathematical concept is not acquired in one step [13], thus we have to take a long journey for developing of the function concept. One of the aim of this process to develop an effective concept image which have an important role in problem solution. The students decides on the basis of a concept image whether a given mathematical object is an example or nonexample of the concept. (Vinner & Dreyfus, 1989). In this paper we are looking for the answer of the following question: what are the concept image of the function concept formed of the students by the end of the primary school (8th grade) and the first year engineering university students?
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Effect of Heat Input on the Toughness Properties of S690QL Steel during Hardfacing
1-13Views:199In recent years, the use of high-strength steels in hardfacing process has become increasingly common. One typical industrial example is the case of hydraulic shears used in building demolition operations, where the components are exposed not only to significant abrasive wear but also to intense dynamic loading. The use of quenched and tempered high-strength steel grade S690QL has become particularly widespread in this field, primarily as the base material for the hardfacing applied to the most heavily loaded regions of demolition shears. However, quenched and tempered high-strength steels are highly sensitive to the effects of the welding thermal cycle, which typically cause detrimental changes in the microstructure and mechanical properties of the heat-affected zone. The thermal cycles occurring during hardfacing differ from those typical of fusion welding, and consequently, the structure and mechanical properties of the resulting heat-affected zone may also vary. In addition, the penetration depth of the hardface layer can differ, which may significantly alter the load-bearing cross-section of the high-strength steel and, thus, the in-service behavior of the component. In the experimental work, hardfaced samples were performed on S690QL base material using different levels of heat input, thereby producing varying penetration depths. The aim of the study was to determine the effect of penetration depth on the resistance of the hardfaced component to dynamic loading. The tests were carried out at both +20 °C and –40 °C. The results clearly demonstrated that samples with deeper penetration exhibited reduced toughness at both investigated temperatures.
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The Influence of the Boundary Conditions on the Buckling of Thin-walled Cans during Manufacturing
41-50Views:300In this paper the effect of the boundary conditions on the stability of thin-walled aerosol cans under axial pressure is investigated. The main objective is to outline the main characteristics of this highly nonlinear mechanical problem and to present methods to simulate the buckling of cans with different boundary conditions. Due to the numerical difficulties coming from the contact between the can and different components of the machines, the effect of the different supports of the can is investigated on the crushing (or buckling) force at which the loss of stability occurs. The commercial finite element software Abaqus is used to solve the problems and to present the efficiency of FE codes in the design process of cans.
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Consumer Perception of Electric Cars in Hungary – Theoretical Considerations and Empirical Results
1-23Views:1121Electric cars are becoming increasingly popular in the automotive industry and among consumers; partly as a result of their environmentally friendly characteristics. The aim of the study is to compare the main characteristics of electric and conventional cars in the context of environmental protection. In the first half of the study, we present the life cycle of electric and conventional cars and we compare the overall environmental impact traditional an electric vehicles. We point out that although the operation of an electric car does not pollute the environment locally, the manufacture, charging and disposal of batteries required for operation raises several issues related to environmental pollution. In the second part, we examine the respondents' attitudes towards electric cars based on our own questionnaire research. On the basis of the answers, it can be said that consumers still consider electric cars expensive and are aware that electric cars address some pollution issues to a small extent.
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Virtual Testing Method of Human Knee Prosthesis
386-392Views:323In 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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Building Information Modelling: Present realities and Future possibilities
377-394Views:327BIM (Building Information Modelling), a term that is drawing the attention worldwide in the construction industry and governments, is a complex concept that involves management effort, tools and applications for enhancing information flow and therefore productivity for projects. This article pretends to briefly explain BIM, its advantages, challenges and potentialities while considering the current adoption of the concept in some countries. Furthermore, the article includes suggestions for the implementation of BIM in an organization as well as in projects and a list with some useful tools for this purpose.
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Examining Organisational Culture with OCAI among Technical Management BSc Students of the University of Debrecen
1-8Views:593Based on the OCAI model, our study analyses and compares two things (1) the corporate culture of the University of Debrecen Faculty of Engineering as it is perceived by its engineering management students; and (2) the culture they think would be ideal. According to the respondents the existing culture is closer to the clan type and further from the market type compared to the average. Their ideal culture is closer to the clan, adhocracy and further from the market (compared to the average). The perceived current and the ideal culture are significantly different only in the adhocracy type. From the 20 items of the OCAI questionnaire 7 were significantly different from the average in the case of the perceived culture and 13 in the case of the ideal culture. Differences between ideal and present cultures are statistically supported only in the following dimensions: dominant characteristics (clan is currently stronger, adhocracy is weaker), corporate leadership (market is currently stronger), strategic emphasis (hierarchy is currently stronger).
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Modern use of geothermal energy in Nagyszénás (Case Study)
106-115Views:426A project based on geothermal energy use in Nagyszénás, Békés County, Hungary, was finished on December 20, 2015. The construction investments were realized with the support of the European Union from tender funds won in the financial cycle of 2007-2013 in the total value of HUF 1.578 billion. The thermal water utilization investment was realized with unique technical solutions in the country, and as a result, a modern, economical heating system using green energy source was built, and now provides energy for the public institutions of the settlement and for the newly established bath complex. During construction and operation, several unforeseen technical problems arose, which could only be solved by using new technical elements. The high salinity and high temperature of the extracted thermal water required special engineering solutions. During operation, modifications and changes in technological elements were required at several points for the safe operation. The purpose of this article is to present these technical interventions, which made the reliable operation possible, thus the system provides a suitable alternative to natural gas-based heating.
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Examination of Consumer Perception of Web Stores by Netnography in the Period of COVID-19
Views:561Online shopping has become more and more part of our everyday lives, as proved by the fact that in the midst of the economic crisis caused by the coronavirus epidemic, online retailing has grown by more than 30% in Hungary. International research has shown that nearly 90% of consumers take into account the online reviews as much as the recommendations of family or friends before their purchases, digital channels, including Facebook have the greatest impact on their decisions. In our research, in connection with a specific campaign, Black Friday, we examined how actively the highest-traffic stores – having online shops as well - use Facebook to reach and influence the customers. We chose netnography as the method of our research, and we analysed the posts published on the Facebook pages of the five chosen online shops, furthermore, the customer reactions and comments given in connection with the posts. Our results show that three of the five chosen online shops applied Facebook campaigns within the action. By analyzing the comments, they were classifiedinto 5 categories based on satisfaction and trust: satisfied, dissatisfied, interested, trolls, and mute groups.
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Maintenance from the Work Safety Point of View
190-196Views:323Deterioration of the technical condition of plant equipment is a common phenomenon nowadays. According to the experience of authorities, all this contributes to the occurrence of malfunctions and accidents. Plants that operate with an inadequate conservation strategy are now nearing the end of their design life, thus posing an increased accident risk. Aging processes are often accelerated by the operator's underestimation of the effects of equipment stress and the extent of deterioration mechanisms, and the consequent inadequate design and operation of condition monitoring and maintenance procedures. The aim of our work is to examine trends in the light of modern maintenance optimization methods and, in connection with this, to make proposals for the optimization of maintenance scheduling for employers.
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Simulation of an Operating Machine in Dust Chamber
266-275Views:283Auxiliary equipment used in the automotive industry, such as generator, air conditioner, or starter, is often exposed to harsh conditions, for example splash water, frost, or serious dust load. Therefore, these auxiliary devices are intended to be prepared by the manufacturers to these conditions. The topic of this paper is a part of the analysis of the dust control of generators, which in principle is no different from the examination of other equipment. The flow around the generator and in the dust chamber was simulated by Ansys FLUENT.
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Modernisation of FESTO MPS Station with Implementation into Cyber-Physical Space
10-14Views:294In the course of our thesis we dealt with the implementation of a manufacturing cell. For this we used the FESTO MPS modules. The production cell is controlled by a PLC. We have not only implemented a unique layout and workflow), but also added new features to the system. This means using two control units, one of which is responsible for controlling the process, while the other is managing a web interface. On the web interface, you can see the warehouse containing the finished workpieces and order palettes assembled from different workpieces, or you can set the type and quantity of workpieces to be stored in the warehouse
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What Drives The Diffusion of AI Recruitment Systems in Swiss HRM? The Importance of Technological Expertise, Innovative Climate, Competitive Pressure, Employees’ Expectations and Contextual Factors
42-84Views:824This study examines organizational, environmental, and contextual factors influencing the diffusion of artificial intelligence recruitment systems in human resources management within Swiss organizations. Based on a survey provided to 324 private and public Swiss HR professionals, it explores how some technology-organization-environment theoretical framework predictors' as well as innovative climate provided by organizations influence the three stages – evaluation, adoption, and routinization – of diffusion of this innovation. To do this, the following article is based on a PLS-SEM structural equation model. Its main findings are that technological expertise, innovative climate, competitive pressure, and expectations regarding future use of the tool by organizations working in the same field are directly linked to the spread of this type of AI tool. However, public-sector organizations are more reluctant about using this type of tool. This aversion can, however, be moderated by an innovative climate and the fact that the HR function plays an active part in an organization's strategic direction. This said, this article makes a significant contribution to the literature about the diffusion of emerging technologies in organizations.
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LSI with Support Vector Machine for Text Categorization – a practical example with Python
18-29Views:681Artificial intelligence is becoming a powerful tool of modernity science, there is even a science consensus about how our society is turning to a data-driven society. Machine learning is a branch of Artificial intelligence that has the ability to learn from data and understand its behavers. Python programming language aiming the challenges of this new era is becoming one of the most popular languages for general programming and scientific computing. Keeping all this new era circumstances in mind, this article has as a goal to show one example of how to use one supervised machine learning method, Support Vector Machine, and to predict movie’s genre according to its description using the programming language of the moment, python. Firstly, Omdb official API was used to gather data about movies, then tuned Support Vector Machine model for Latent semantic indexing capable of predicting movies genres according to its plot was coded. The performance of the model occurred to be satisfactory considering the small dataset used and the occurrence of movies with hybrid genres. Testing the model with larger dataset and using multi-label classification models were purposed to improve the model.
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A Slurry-Pot Abrasive Wear Test Device for Several Composite Materials
437-444Views:283To 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.
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Flexibility Analysis Of Inventory Cost Model With Ergonomics
166-173Views:343The economic and environmental sustainability issues in supply chain management have integrated by many researchers in the past decades. The ergonomics as a social aspect of sustainability had received a little attention by researchers. Therefore, the aim of the paper is analyzing the flexibility of developed inventory cost model with relaxation allowance and endurance time as a social aspect of sustainability. The effects of distance, unit weight of item and total number of items on relaxation allowance, the total cost of logistics operation and the EOQ model were investigated. The analyzed mathematical model was a single operator-single material model which covered transportation of fixed amount of raw materials from storage plant to production plant by manual material handling with simple cart and picking, storing, pushing and pushing back with empty cart for manual handling of the products. The different parameter values applied for analysis such as total amount of handled items (Q) changes between 500 pcs to 2750 pcs, unit weight of item (w) changes between 0.1 kg to 1 kg, distance of movement by manual material handling for picking and storing motions (d1) changes between 2 m to 3 m and the distance between the storing equipment and the supermarket of the production line for pushing motion (d2) changes between 15 m to 20 m. The results of the analysis indicated that the longer the distance of movement for all motions leads to decrease in savings of the model compared to EOQ model. The increase in unit weight of item is increase the savings obtained from application of our model and decrease the optimal lot size. There was no specific change on savings or optimal lot size as the total amount of handled item is increase. The compared results indicated that an increase in d1 and d2 lead to an increase in optimal lot size and increase in total cost of the model. Consequently, the analysis has shown that a decrease in lot size would be the better way to improve both ergonomic conditions and total cost of production in any different parameter values. Finally, the analysis of the inventory model with ergonomics were proved that this model is suitable for different industrial practices.
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Transportation System of Major Cities in the Middle East
50-53Views:353The quality of transportation has a great effect on the quality of our everyday life and the future of our planet. In contrary to Europe, transportation culture of the big cities in the Middle East region has grown fully different way. These Middle Eastern cities tend to have a different historical, traditional and structural background compared to other cities all around the world. One of these big cities is in the focus of our paper: Rijad, with 6 million inhabitants is the archetypal car dominated city of the Arabic world. We also elaborated a comparison to 4 other cities: Dubai as a city similar to Rijad, Amsterdam as a city with a modern green attitude, Budapest as a metropolitan city in Hungary and last but not least Debrecen which is a Hungarian city with moderate population. As a lesson learnt, we try to give some possibilities and outlooks for Rijad, in order to improve the structure of transportation.
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Effect of the Friction Coefficient on Clinch Joints
86-90Views:423In this study the effect of the friction coefficient on the clinch joints was examined in experimental and numerical way also. The knowledge of the frictional behaviour during the mechanical joining (i.e. clinching) is important from the point of view of resultant geometry which is related to and influence the strength of the joints, and furthermore the maximal forming force is limited by the tool’s failure load which can be reach with a non-favourable frictional condition, as well the aesthetic aspect are also has an importance in some special cases (e.g. in automotive industry).