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Evaluating the Efficiency of Polyhedral Mesh Elements in Solving the Problem of the Flow around Ship’s Rudder
241-256Views:445Meshing is one of the crucial key features to the success of CFD based simulations, this study is evaluating the efficiency of polyhedral elements in solving the problem of the flow around ship rudder, using a Reynolds-averaged Navier-Stokes turbulence model (SST k-ω), and compares it to a tetrahedral based mesh, considering that polyhedral elements were neglected in the past due to difficulties in implementing them, this was solved by introducing a tool by ANSYS that converges tetrahedral elements to polyhedral element, and integrating it into FLUENT software, the model was validated by comparing it with previously validated model which used the full version of ANSYS, this study was concluded using the academic version, but still it was able to produce satisfying results in predicting the lift and the drag coefficient, the pressure around the rudder surface, the velocity and the turbulent kinetic energy, finally the mesh quality was evaluated using the orthogonal quality criteria, the results showed the supremacy of the polyhedral elements in saving time and computational resources and improving mesh quality, and keeping high level of accuracy in predicting the results.
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Tribological Behaviour Comparison of ABS Polymer Manufactured Using Turning and 3D Printing
46-57Views:367Additive and subtractive manufacturing of Acrylonitrile Butadiene Styrene (ABS) were employed for fabricating samples. The Additive manufacturing was represented through 3D printing, whereas subtractive manufacturing carried out by Turning. Some developments have been applied for enhancing the performance of the 3D printer. Tribological measurements of the turned and 3D printed specimens have been achieved. Studying the difference between static and dynamic friction factors and the examination of wear values were included. A comparison of the tribological behaviour of the turned and 3D printed ABS polymer has been investigated.
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Examining the Functioning of Organizations from the Aspects of Organizational Culture and Leadership
371-381Views:456Organizational culture and Leadership both have been under research for a long time, as they play a vital role in the performance of an organization. The organizational culture is the set of rules or acts as a guidebook of an organization for achieving the objectives while leadership defines these rules and implements them as well. Organizational culture is dependent to a great extent on the norms and values of the society or the country where it is located. Important for achieving the objectives of an organization, this factor plays a vital role while setting the organizational culture. Incorporating organizational culture and then sustaining it is done by the leaders. Leadership if does not play an effective role in regards to implementation of the organizational culture, can collapse the organizational structure. Leaders are required to develop the qualities according to the organizational culture and should be responsible to come forward to transform if necessary and implement the system. The organizational culture should fulfill the needs of the organization’s goals and the norms of the society. Both leadership and organizational culture are co-dependent on each other and should be understood together.
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International Coffee Trade Network Analysis
393-404Views:461Coffee is one of the most consumed beverages in the world. It is the second largest traded commodity after petroleum. It is crucial for the economy and politics of many developing countries, as its cultivation, processing, trade, transportation and distribution create jobs for millions of people. The analysis of network connections and structures became popular in the field of sociology, whereby the term Social Network Analysis (SNA) is derived. The method is well suited for the complex examination and modelling of composite social structures. The social network is defined as a finite set of social actors and the relationships between them. Modelling of complex networks now apply in countless locations, from social media through the pharmaceutical industry to economic and commercial processes. Our study examines changes in international coffee trade through a network analysis. Introducing the complex networks investigate by our, highlighting major changes in international coffee trade.
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Food Industry 4.0 Readiness in Hungary
1-12Views:505In terms of production value, the food industry is the third-largest in Hungary, the first in Hungary in terms of the number of employees, and the first in Europe in the processing industry, as well as a significant user of resources. The research examined the state of art of digitalization readiness, focusing on I4.0 technologies, which supports the management to operate more efficiently the enterprise and to make better decisions. So the focus was on integrated enterprise information systems, management support systems, business intelligence systems, industry 4.0 technologies, and issues related to their application. The analysis based on an online questionnaire survey the request sent to 4.600 enterprises, the response rate was 5% which was representative of the branches of production, covered the Hungarian food and beverage manufacturing sectors in 2019. The companies were asked the most critical technologies in development, going towards Industry 4.0. The research tools were LimeSurvey, Mailing List Server, Excel, Power BI (Desktop, Publishing Server to distribute the results). The used analysing methods were making calculations, pivot tables, models, dasboards. We found that a significant portion of businesses, 78 %, use mobile devices in the manufacturing process. The three most relevant digital technologies are geolocating (GPS, GNSS), cloud computing, and sensor technology. The current level of digitalization and integration cannot be said to be high, but respondents are very optimistic about expectations. Improvements are expected in all areas in the next 2-3 years in terms of digitalisation and integration. Vertical integration involves, first and foremost, cooperation with partners in the supply chain. Horizontal integration means close, real-time connectivity and collaboration within the company. Unfortunately, between 6% and 15% of SMEs (approximately 9% on average) and large enterprises, 36% have a digital strategy. According to the survey, the sector needs significant improvement and creating a digitalization strategy.
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Quality Development of a New Type Pharmaceutical Formulation
112-127Views:412The aims of companies to understand internal and external customer demands in order to improve their existing products and develop new ones. Product development aims at understanding customer demands that may influence the production of the product to be manufactured. As a first step in the process, the customer voice method was used to define demands with measurable parameters. A questionnaire survey was used to prioritise them, which were then compared and ranked using a preference matrix. Within the QFD method, technical parameters influencing the satisfaction of customer demands were determined. A correlation matrix was established and the relationship between the technical parameters was investigated. A competition analysis of technical parameters and customer demands was carried out. From the absolute and relative weights, it is easy to establish the order of the technical parameters, so that the most important parameter in terms of meeting the defined customer demands is the determination of the ratio of raw materials, and important parameters are chemical stability, pharmaceutical formulation and particle size.
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Investigation of the Resistance Force Acting on a Sailing Craft in the Case of a Change of Draft Caused by a Change of Powertrain Using Numerical CFD Simulations
30-35Views:382Nowdays In the case of recreational craft, interfering with motor drive solutions is a common workflow due to increasingly strict rules for environmental reasons. When switching from an internal combustion engine to an electric engine, the change in draft varies from boat to boat, but it can be said in all cases that as the mass changes, so does the draft. Because of this, the magnitude of the resistance force acting on the ship also varies. In this paper, we examine, through a specific example, the benefits of a change in dive caused by weight gain at different travel speeds.
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Review of Modern Vehicle Powertrains and Their Modelling and Simulation in MATLAB/Simulink
232-250Views:1384Thanks to technological advances and environmental standards, as well as changing usage patterns, road vehicles are constantly developing. Electric and hybrid vehicles are playing an increasingly important role in today’s road transport. The most significant changes are probably in the powertrain of vehicles. The efficiency of internal combustion engines increases while their emissions continue to decline. In addition, high performance electric motors, batteries and even fuel cells play an increasingly important role in hybrid and electric vehicles. In this publication, we review the drive systems of current modern vehicles and the types and characteristics of their major components. We also review the available models and computer programs for their simulation, focusing mainly on MATLAB/Simulink applications. Based on this, we can develop our own models and simulation programs which will help us to perform different driving dynamics simulations and to compare the performance, dynamic and energetic characteristics of these powertrains and their components to each other.
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Testing of Micro Switches for Garden Tools
206-213Views:198The aim of this paper is to introduce the design of testing method for the prediction of the life and acceleration methods of the micro switches applied in different type of garden tools. These products will be tested for complex stressing, for example higher temperature, humidity, current load and so on. Therefore, the most important information and multi-factor acceleration models are summarized, the Weibull, the lognormal and the exponential distributions which are suitable for performing and evaluating tests.
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Impression Management Strategies Used by Foreign Students
127-132Views:242In this paper, we examined a general human behaviour, the impression management among university students. People are interested in how others think about them. At the organizational level, they can also benefit from being positively judged by others. Effort to create this positive image is Impression Management, which has several measurement options. In this paper, we conducted research on the impressions strategies used by first year international students of University of Debrecen, Faculty of Economics and Business Administration, Bachelor in Business Administration and Management programme. In our analysis we used the questionnaire consisting of 22 questions developed by Bolino and Turnley. We analysed what strategies are typical for the examined student group and to what extent? Are there differences in the strategies employed by men and women and depending on their cultural background.
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Application-oriented Mathematics Education at the Faculty of Engineering, University of Debrecen
36-42Views:277At the Department of Basic Technical Studies, Faculty of Engineering, University of Debrecen we have been dealing with the methodological reforming of mathematics education for more than ten years now. The recently published course book “Mathematical Tools in Engineering Applications” is the result of this long term creative work. The book presents the applications of the most important mathematical tools (vectors, matrices, linear functions, complex numbers, differential and integration calculus) in the different fields of engineering, natural sciences and economics. The aim of the authors with the recent publication is the presentation and popularization of the above book together with the educational and methodological trend it represents.
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Examination of the Relationship between Renewable Energy and Economic Performance
234-243Views:382Many countries are making considerable efforts to achieve solutions to environmental problems that we face today and developing renewable energy resources is one of the potential long-term solutions that constitute an absolute priority from a sustainable development perspective. The usage of renewable energy is one of the critical future challenges to reduce greenhouse gas emission and decrease energy dependency at the same time. Thus, replacing traditional energy sources with renewable ones, like Hydropower and wind power to produce electricity instead of fossil fuel. The objective of this study is to find a relationship between renewable energy consumption, macroeconomic factors, and the environment. There is a reliable and significant (at 1% significant level) association between REC with GHG and GDP and a relatively strong association with EC.
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Entrepreneurial Climate – Management of Women's Entrepreneurship
69-74Views:238Entrepreneurship, which people can have without formal economic education, is a tendency acquired through upbringing in the family, competition in school, implies risk and constant self-affirmation through the acquisition of profits and losses, so that it represents the sum of successes and failures, victory and defeat. In the last thirty years, female entrepreneurship has been developing more and more, especially in less developed countries, the reason for such growth is primarily reflected in the promotion of equality between men and women, the right to education, and the development of democracy. Female entrepreneurship is a significant factor in economic development, so the national economy becomes richer. The subject of this research are the entrepreneurial climate in the Balkans compared to the world in terms of female entrepreneurship, what is the role of the family in starting a small business, as well as its survival and growth. In the study the results of previous research in this area. The research method is based on a comparative analysis of studies dealing with this problem from the territory of Balkans. It can be concluded that in the Balkans, female entrepreneurship is still in its infancy, it is about a very small percentage of female entrepreneurs, although according to research, it is evident that there has been no major progress in the last 15 years. Recommendation In the countries of the Balkans, there is a good entrepreneurial climate for the development of female entrepreneurship, especially because women can work from home, and in the future it is necessary to go in this direction.
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Enhancing Sustainable Production Through Continuous Improvement: Evidence from Nigeria’s Manufacturing Sector
1-20Views:130The 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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Thermoelastic Problems of Multilayered Spherical Pressure Vessels Subjected to Axisymmetric Loading
106-115Views:308This paper deals with the linear thermoelastic analysis of functionally graded multilayered spherical bodies subjected to constant mechanical and thermal loading. The temperature field is arbitrary function of the radial coordinate, the material properties and the radial body force vary according to power law functions along the radius of the sphere. An analytical method is presented to calculate the displacements and stresses within the multilayered spherical body. The method is expanded to tackle the problem of spherical bodies made from radially graded materials with temperature dependent material properties. The results are compared to finite element simulations and other methods.
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Examining the Movement Differences in the Behavior of Normal and Rack Railway Vehicle
96-103Views:418The rack railway is a special type of railroad. There weren”t much built worldwide, and their number is decreasing. Now, in Budapest, there is a possibility to create an interoperable vehicle, based upon the experience gained from the previously operated line, and all the research regarding its unique characteristics. One from the many important sector of its operation, is the rail/rack/vehicle system. Its mechanical model is far more complex than a traditional railroad vehicle. We will demonstrate its behaviorial differences from a traditional railroad vehicle.
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Do Talent Management Practices Affect Organizational Culture?
495-506Views:1060The purpose of this paper is to enhance the readers' understanding of the domain of talent management and organisational culture and how talent management becomes one of the important strategic tools to improve the work environment, specifically as a tool for enhancing the organizational culture. The paper also attempts to probe and aid readers in understanding to what extent talent management affects the organizational culture. This paper is based on secondary research and articles in the areas of talent management, organizational culture and the relationship between them. The author has reviewed the existing body of work on these topics to arrive at the analysis of the relationship between talent management and organizational culture. As well as measuring its impact on the whole organization by reviewing the existing literature.
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Investigation of Parental Roles in Relation to Youth Football
105-114Views:381My research is based on the fact that, thanks to the development of sports and the capital flowing into the sector, youth sports are no longer just a useful way of spending free time for children and a mean for educating them for a healthy lifestyle, but also an opportunity to lay the foundation for an adult sports career and, with it, secure future existence. In order for the training to be effective and productive, one of the many components is the existence of parental support. Youth competitive sports pose many challenges for a family and influence their lives from several aspects. In my research, I examined how youth sports affects parents in terms of certain demographic variables, what changes it generates in their family life, and I also paid attention to what expectations the family has about sports. The basis of the study is an online questionnaire survey, which was filled out by more than 700 parents of youth football associations. My research revealed that, in accordance with the previous literature related to the topic, their children's sports have a significant impact on the lives of the parents and they set different expectations regarding it, which are also influenced by various social and demographic factors.
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The Role of Employee Participation and Resistance in the Success of Change Management
22-30Views:754Successful change in the lives of organizations has played a particularly important role in the recent turbulently changing decades, and leadership-follower relationships need to be addressed in order to maintain performance. Participation should be ensured for members of the organization and emerging resistance should be addressed. The subject of my research was to examine whether the assessment of the success of change is influenced by the provision of opportunities for employees to make suggestions and their opposition to change. By performing chi-square tests, I came to the conclusion that if the opinion of the worker is heard, they are more likely to judge the change to be successful, however, the manager is not affected by the involvement of the employees in this. However, there is a correlation between employees' resentment to change and the success of change, both from the employee and managerial side, change is more unsuccessful if resentment develops. Based on the results, both factors are important. It is worth drawing the attention of managers to the need to ensure participation, as failure to do so can lead to dissatisfaction among employees, which can also have a negative impact on the success of the organization.
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Vehicle Dynamics Simulation in Matlab/Simulink Environment
36-41Views:467In the following we are researching different methods of vehicle dynamics simulations. Starting from a simple two-wheeled vehicle model, we are showing ways to simulate the movement of vehicles with real suspensions on any surfaces. MATLAB, Simulink and Simscape provide very suitable resources for the above mentioned purposes. The benefits of such vehicle model become obvious because of the fact during the physics simulation we can access all the data we need to simulate any control algorithms for vehicles: in this article we are presenting a simple ABS control simulation.
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Evaluating the Entrepreneurial Performance in South America. Case of Chile
13-28Views:427The research objective is to explore Chile's entrepreneurial landscape by assessing individual characteristics and institutional factors through a 'pillars' framework and compare it against Colombia, and Brazil; to identify socio-economic, individual, and institutional differences using the Global Entrepreneurship Index (GEI); to apply bottleneck approach to highlight areas requiring policy intervention. GEI features individual and institutional stage variables in a method where every variable collaboratively interacts, incorporating 14 foundational elements and three sub-indexes: attitudes, abilities, and aspirations. Ranking 18th on the GEI globally and the best in Latin America, Chile excels in key entrepreneurial pillars, showcasing strengths in innovation and a robust entrepreneurial culture. Brazil closely rivals Chile in competition and networking, emphasizing political and economic influence. Colombia surpasses Chile in internationalization and growth-stimulating policies but faces challenges like historical conflicts and wealth distribution. This study identified areas where immediate policy intervention may be necessary by examining Chiles's entrepreneurial ecosystem. The Penalty for Bottleneck (PFB) technique identified the weakest pillars highlighting process innovation, competition, and internationalization. The primary component identified as a bottleneck for resource allocation is Process Innovation, accounting for 73% of the allocation, followed by Competition at 23%. The findings show that allocating more resources to process innovation may improve greatly the overall GEI score.
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Examining Used and Sportswear Supply Chain Strategy and Indicators
86-98Views:357The following study presents the supply chain strategy of a second-hand and sportswear company in Hungary. The study discusses the main tasks of supply logistics, the level of logistics service, the main determining elements of the level of logistics service, and the measurement of customer satisfaction. From the first step of the process, we can fully follow the processes until the last activity. We can learn in detail about the sub-processes, such as: types of clothing collection, sourcing, warehousing, selection, disassembly, processing, receipt of goods and sales. The aim of the study is to make the processes more transparent for everyone.
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The green methanol - playing a role in sustainable energy management
249-258Views:290Global energy demand is constantly increasing, so the energy sources we use, and the efficiency of energy use are of paramount importance for the future of humanity. Methanol can play a key role in the sustainable use of natural resources, in the efficient and smooth transition from a fossil oil-based energy system as well as in reducing greenhouse gas emissions. Long-term thinking will result in an increase in the use of renewable energy sources, which will favour the spread of green methanol technology and thus the use of a carbon-neutral fuel. The raw materials for the production of green methanol may include municipal solid waste, agricultural waste, renewable hydrogen and carbon dioxide and the methanol has many uses, both as fuel and chemical feedstock. It also provides an opportunity to chemically store excess renewable energy from intermittent sources, thereby reducing dependence on fossil fuels. The price of electricity used for electrolysis is the main determinant of the economical production of green methanol, so the reduction of the cost of solar and wind energy greatly contributes to the competitiveness of carbon-based production.
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Forces Attributed to Dark Matter May Originate from Entangled Particles as Seen in the Shape Of Galaxies Formed by Grbs
23-32Views:269Recently, it has been suggested that entangled particles may be connected by a wormhole. If that is right, what is the distance between them we have to take into account when applying Newton's law of universal gravitation to these particles? We propose the idea that these particles may attract each other regardless of distance, resulting in a force that behaves exactly the same way as the force derived from presumed dark matter. Traces of such a force seem to be present in galaxies due to gamma ray bursts (GRBs) that produce entangled particles which hit various objects. We can observe that in barred spiral galaxies the arms always pass through the nucleus of the galaxy so we believe that the very first GRB happened at the central supermassive black hole (SMBH) and the arms are the traces of this ancient GRB. If we see an unbarred spiral galaxy, we can be certain that the arms do not pass through the core and we think the very first GRB happened close to the core. Ring galaxies may also be considered as a type of spiral galaxies, since there is a section where the ring is broken, i.e. where the arms do not meet. So the very first GRB happened far from the core. Elliptical galaxies may have resulted from an ancient GRB which hit from outside. The arms rotating in opposite directions of the NGC4622 galaxy support our hypothesis. Finally in the silk threads of the spider web of the universe, the traces of GRBs can be seen.
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Vehicle dynamics modelling of an electric driven race car
106-114Views:243In the following we are presenting a vehicle dynamics simulation program developed in MATLAB environment. The program is capable of calculating the dynamics functions of a vehicle from its technical data. The program has been successfully applied for the optimization of the technical data of an electric driven race car that was designed and constructed at the Department of Mechanical Engineering of the University of Debrecen.
