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Bekele Desta and M. Lunga: Segmenting the Impact of Organizational Structure and Leadership on Project Resilient and Project Success in the Ethiopian Construction Industry: a FIMIX-PLS & PLS-POS Approach. International Journal of Engineering and Management Sciences. vol. 10, no. 3, pp. 73–103, doi: 10.21791/IJEMS.2025.17.
122-123Views:38In the original publication, the authors identified four errors.
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The Economic and Social Effects of the COVID-19 Epidemic in the European Union over the Past Year, Especially in Hungary
67-79Views:2366The apparence of the COVID-19 pandemic at the beginning of 2020 affected all countries in the world, entailing major changes in everyday life. In our study – in a one year perspective – we summerize the socio-economic effects of the COVID-19 pandemic on various economic sectors and their consequences for the European Union and Hungary. As a result of the pandemic restrictions the role of some sectors were decreasing considerably, while on the other hand the other sectors emerged and underwent a significant improvement. The growing trend of working from home, as well as the decline of the tourism, the catering service and the entertainment industry has led to a change in the behavior of the population. . Changes during the pandemic period led to an increase in wealth inequalities.Changes during the pandemic period led to anincreas in economic inequality. The transformation of consumers’ values and income situation is having an huge impact on all sectors of the national economy. When reflecting upon the current situation, the following questions arise: When will the declining businesses be able to recover? Will they be able to achieve their pre-pandemic profit level, and if yes, how long will it take them?
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Analysis of Vibration During Turning Process of Different Materials
200-205Views:255In this article, we would like to introduce the problems caused by vibrations in case of polymer turning processes. Nowadays there is a lot of research in this topic, to avoid the unnecessary phenomena of vibrations. The two most common methods are the Spindle Speed Variation (SSV), and the Vibration Assisted Machining (VAM). In case of SSV, the CNC machine can increase and decrease the speed of spindle continuously during turning which can significantly reduce the effects of chatter. This method is beneficial for longer workpieces when there is not any support except the chuck. Vibration-assisted machining can be used to minimise the problems caused by vibrations. VAM combines precision machining with small-amplitude tool vibration to improve the fabrication process. It has been applied to some processes ranging from turning, drilling to grinding. Based on the enumerated above we made some trial measurements about the basic vibrations of the turning tool shank. The tests were done on an NCT EUROturn-12B CNC machine which can found in the workshop of our institute. The tested material was Polyamide 6 because this is the most commonly used polymer in the industry. In the future, we would like to test some other basic and composite polymer materials too. The equipment was served by a specialist from SPM Budapest Kft. With these tests, our goal was to make sure that the equipment and the measuring setup are suitable for our future research.
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Literature Overall of Fatigue Analysis Approaches of Vehicle Components Made of Rubber
130-140Views:316Generally, the most frequently used structural materials are metals which have high strength and stiffness. However, there are many cases when other important properties come to the front, as well as high deformation capacity with elastic behavior, high viscosity namely good damping effect. Due to its above mentioned properties, rubber is widely used in vehicle and automotive industry. Vehicle components made of rubber usually exhibit large deformations. Cyclic finite deformations generate temperature in hyperelastic materials. Furthermore it is necessary to take into consideration the effects of ambient temperature. The mechanical properties of rubber depend on temperature and temperature changes can accelerate chemical alteration processes which lead to the material deterioration and fatigue processes. Research on fatigue behavior and fatigue properties of rubber has a great significance for predicting fatigue life and improving durability of rubber products. There are several studies on the fatigue behavior of rubber-based materials, but there is less research in the fatigue life prediction considering the influence of temperature and temperature changes. First purpose of this paper is summarizing the influence of temperature and temperature changes on the fatigue behavior of rubber. The second purpose of this study is to provide an overview of the state of the art on the fatigue life prediction of rubber with primary focus on the different methods available for prediction of fatigue life under the influence of temperature and temperature changes.
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Maintenance Strategies and Life Cycle Costs of Renewable Energy Systems
106-116Views:262Life cycle costs are important factors in decisions on renewable energy investments. Since maintenance costs generally constitute a high portion of the life cycle costs, the maintenance strategy applied in a project can affect the bottom line significantly. The effective maintenance tools used in the production industry (e.g., diagnostics, condition monitoring, data management, integrated information systems, machine learning, and automated decision making) can be involved in planning and maintenance of renewable energy systems to gain the benefits of these approaches. In this paper the effects of maintenance strategies on life cycle costs are investigated and the benefits of up-to-date condition monitoring techniques are presented through case studies.
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Consumer Perception of Electric Cars in Hungary – Theoretical Considerations and Empirical Results
1-23Views:1020Electric 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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The Impact of Electrical Vehicles on Sustainability: Jordan as a Case Study
393-403Views:365The Global concern is moving toward making a revolution in favor of exploitation of renewable energy in order to improve environment conditions, limit emissions and minimizes consumption of non-renewable resources within the planet. In this context, it is necessary to focus on the transport sector as it contributes of at least 30% of the total primary energy consumption. Therefore, a set of rules must be developed to maintain economic, environmental and social sustainability to address the problems so as not to increase their severity and these cannot be done unless there are joint measures and regulations from governments, companies, manufacturers and users. Unfortunately, the Jordanian transport system mostly depend on the individual transport which supported by cars, and that because of the weak role played by the public transport sector, especially at the capital, Amman. Buying hybrid cars (internal combustion engine + electric motor) and Electrical Vehicles (EV), in the past few years in Jordan is increasing, which is compatible with the global trend to use Electrical Vehicles (EV) instead of Internal Combustion Engine vehicles (ICE) powered by fossil fuels, this issue will have a direct and indirect impact on gas stations companies, also it will have direct impact on labor sector and the current car industry since electric charging stations as well as EV manufacturing is not labor intensive. The main purpose of the study is to show how much it is necessary now to start theoretical assumptions through studying the expected annual increase in passenger cars and its impact on sustainability and predicting the future fuel consumption and emissions and compare them with the base situation.
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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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Future Power Plant Portfolio Analysis from the Point of View of Minimum Cost and Emission Optimization
61-77Views:257The article examines the expected composition of the power plant portfolio in Hungary by 2030. The indicators considered are the life-cycle unit costs (LCOE) and the life-cycle specific carbon dioxide emissions (LCA(CO2)) of the power plant types. The minimum of these two indicators, as objective functions, is determined by a linear programming method for the power plant portfolio. The results show that the LCOE minimum for the power plant portfolios in 2030 is worse in absolute terms and better in specific terms than in 2021. In both absolute and specific terms, the LCA(CO2) minimum is more favourable in 2021. These results are met under the thirty and twenty-five percent electricity import scenarios. With twenty percent imports, the absolute values are worse and the specific values are better for both indicators. On the other hand, the results of the calculations for 2030 fall short of the 2030 Agenda of the Institute for a Green Transition. This is due to the delay in commissioning a new nuclear power plant and the transformation of industry with increasing electricity demand. For the portfolios under review, a minimum of thirty percent of domestic generation from renewable sources is met. This contributes significantly to the European Union's ambition for the sector to be net greenhouse gas-free by 2050.
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Improving the Work Breakdown Structure of the Plant Installation - Case: Asphalt Plant
174-187Views:580The improvement of the project management forced the industrial organizations to focus on using the project management techniques in their industry, to plan and control the workflow to achieve their targets, further to increase the satisfaction of their customers. One of the most common project management tools are used is the work breakdown structure (WBS), which provide a framework for the implementation of the project scope including project planning, scheduling, monitoring, control, and estimation. Depending on the top-down approach the project activities will be broken into smaller parts that can be measured and controlled during the project implementation. The well-defined construction of the structure contributes to making the project more realistic and visual. However, the misunderstanding of the project WBS among the project team creates deflection and misinterpretation of the project scope. The main issue of this research is to improve the WBS of the installation plan and develop a standard WBS for plant installation. The research was limited to Asphalt plant installation WBS as a case study to identify the weaknesses of the current WBS at the case company which leads to extra installation time and cost. The research is offering a template WBS based on the company logic, defining the frequent risks that affect the plant installation based on the WBS and suggesting a suitable response strategy by recommending a control framework to monitor and control the WBS schedule throughout all installation phases.
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Temporal Changes of Pyrite Oxidation Rate in Bolivian Sulphidic Mining Wastes
194-202Views:208Since the 70's, when huge sulphidic open pits were developed, the acidic rock drainage (ARD) become the leader problem of the sulphidic mining industry. Although the recycling is an essential technology, it cannot cover the demand alone, thus mining activity needs to continue. Acidity in mine drainage commonly requires most of the attention, but the main problem is the caused elevated level of metal mobility and leaching, which are generated by the increased rates of sulphide weathering under acidic conditions. The Itos mine is a polymetallic vein deposit in Bolivia, had been mined for silver and tin until 1990, leaving behind much and huge tailings and mine waste heaps, where quite often the pyrite content exceeds 10 %. Serious ARD effects take place in the mine waste heaps. These processes can be well characterized with the pH 1 or 2 of the seepage water, which forms serious alteration in the waste itself and the neighbouring rocks. In three consecutive years, the pyrite oxidation rate was investigated on the same 7 samples by humidity cell test. 5-6 months pauses were left between the humidity cell test periods, which mimics the alternation of wet and dry periods, typical for the place. The results give much more information, than the oxidation rate in the individual test periods, showing the changes by time. This applied method gave good result to characterize the behaviour of the waste in long-term. The column test was complemented with mineralogical analyses, such as electron probe micro analysis. The mineralogical and column test analyses show, that the changes of the pyrite oxidation rate split the samples into three different groups, one where the oxidation rate decreases, second where it increases with time and the third where oxidation rate is maximal and stays stable for several years.
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Optimization of Automotive Industry’s Manufacturing Process with Lean Tools
81-89Views:538Lean plays i mportant role in industrial environment. Automotive industries use lean tools in order to reduce cost and i mprove productivity. To achieve the company's objectives and so lve the detected problems I also used lean tools. By using lean tools we want to decrease total process cost (TPC). In order to achieve this target, the three-shift production has to reduce in two-shift production, which result decrease in the human resource costs and production costs. In order to reduce shifts we have to increase overall equipment efficiency (OEE) and eliminate minimum 50% of wastes by implementing 5s methodology, using Poka-yoke and scheduled maintenance.
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Comperative Economic Analysis of the Determining Leagues of European Clubfootball
22-35Views:641Nowadays sport is not just all about entertainment, or about social cohesion but also it has serious economic and business aspects. Sporteconimics is an individual concept and sector. Sport businesses are contributing more and more to national incomes. Football business are specially important parts of this complex system called sporteconomics. The aim of my research is to create an economic and also comparative analysis of the five top European football leagues, also called as the “Big5” which are responsible for 74% of the total football revenue in Europe. By the analysis of the 2019 UEFA report it can be stated that in these leagues more than 60% of the competing clubs achieved positive operating profits, but the structure of their revenues warns them to look for opportunities to increase their operating revenues. According to the data it is clear that wage cost is the most significant cost element in the industry as they cover 53-68% of their total revenue. These statements set the course for the economic development of European football. The management of these outstanding football clubs may give example to the ones falling behind including Hungarian football businesses.
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Defect Analysis of Bearings with Vibration Monitoring and Optical Methods
1-12Views:330Diagnosis of bearings with advanced methods gained remarkable roles in the previous years. This article focuses on the manufacturing defects and methods to reveal and classify them. During manufacturing several faults could emerge because of the grinding operation, tool wear and chatter vibration. Inproper handling of the bearing parts because of the collosion to each other and the storing box that causes deformation. To reveal these problems several methods are applied in industry. For deeper surface analysis nitric acid can be used to initate the finished surface of the roller then natrium-carbonate that nautralize the elements. Vibration analysis in its standard Fourier form is not a new achivement but other mathematical tools could be applied to condition monitoring such as wavelet transform. It is an efficient tool for analyzing the vibration signal of the bearings because it can detect the sudden changes and transient impulses in the signal caused by faults on the bearing elements. In this article five different wavelets, Daubechies, Gaussian, Coiflet, Mexican hat, Meyer are compared according to the Energy to Shannon Entropy ratio criteria to reveal their efficiency for fault detection.
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Sport Consumption, Fan Engagement, Sport Statistics – Post-specific Passing Characteristics in Football
Views:879Digitalization and the explosive development of technology have led to significant changes in football. Due to the increasing amount of data available through various sensors and other data collections, we can observe the rise of data-centric, analytical and statistically oriented thinking in football, which is also of interest to fans. Digitalisation is also closely linked to sports consumption, which is why we have seen significant changes in this area in recent years. The pandemic has further amplified the speed of digital transformation in the sports industry. One of the most important contents for sports organizations and their fans is the in-depth sports statistics and analysis that enhances the consumer experience. In our study, we examined the most common performance indicator in football, passing. Our goal was to examine the position-specific pass characteristics in detail, therefore we also examined different pass properties in our research. As a model for our analysis, I chose the premier league, which has the highest UEFA coefficient. The three rounds (rounds 30-32) of the championship season 2019/2020 have been recorded and analyzed in terms of passes. there was a significant difference between the average number of passes per game between defensive and offensive players (t=7,988, p<0.05). There is also a gradual decrease in the number of passes attempted per match and the accuracy of the pass in the examination of the middle positions when examining the positions in the depth of the pitch. For both pass accuracy and average pass count, the decreasing ranking corresponds to the position of positions on the pitch (order: 1, central defender 2, defensive midfielder 3, inside midfielder 4, attacking midfielder 5, striker). In the value indicator of the position for passes, offensive positions performed more effectively than defensive positions. The extreme positions also stand out among the attacking positions, where in the case of the position value per pass number, 23.3% of the total test was completed and 14% of the amount of the established position value indicators was provided by these posts. Overall, our study points to post-specific pass characteristics and, knowing this, we can state that the comparison of players' passing performance is relevant if the players are in the same or related positions.
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Development of a Small-Scale Plastic Recycling Technology and a Special Filament Product for 3D Printing
365-371Views:606In 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).
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Present and Future of Industrial Robotisation
13-24Views:455The following paper analyzing the installation of industrial robotisation in sectors and regions, in addition carry out forcastings on historical data. In recent years, automation and the use of industrial robotics have increased exponentially in the manufacturing sector. Given that companies prioritize enhanced production efficiency, quality assurance, and safety, it is evident that substantial investment and implementation of automation continue to occur in manufacturing facilities worldwide. The number of industrial robots globally has been growing steadily since 2010. However, the rate of growth has slowed from 2020 onwards. The impact of the Covid-19 epidemic was still felt in 2020, but the deployment of industrial robots increased significantly in 2021. Global industrial robot deployment is projected to continue to grow in the coming years, although the rate of increase may vary between regions and countries. The analysis showed a number of differences between regions in the number and growth rate of industrial robot deployments. Asia and Australia are the largest markets for robots and the number of robots deployed is expected to continue to grow in the future. Europe is the second largest market and, although growing at a slower rate, industrial robot deployment is also increasing steadily. In the Americas, growth is slower than in other regions, but still increasing. Global growth trends suggest that there will be further growth in the coming years and that the deployment of industrial robots will become more widespread in different parts of the world.
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Building Information Modelling: Present realities and Future possibilities
377-394Views:265BIM (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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Exhaust System Muffler Volume Optimization of Light Commercial passenger Car Using Transfer Matrix Method
132-138Views:329Nowadays, the automotive industry is focused on weight and size reduction. Main advantage of this weight and size reduction are improving the fuel economy. The specific fuel consumption of a vehicle can be improved through e.g. downsizing area of heat loss, if we focus on vehicle with weight reduction. Weight reduction can be done by replacing material or by changing the size (dimensions) of components. In the present work we have focused on Audi A6 muffler, troubleshooting and optimizing the muffler by changing pipe length of inlet and outlet, also by replacing the original mesh plate to porous pipe. Based on optimization, prototype has been built with the help of 3D design tool CATIA V5 and the calculations of transmission loss (TL) have been performed by MATLAB. Plane wave-based models such as the transfer matrix method (TMM) can offer fast initial prototype solutions for muffler designers. The principles of TMM for predicting the transmission loss of a muffler was used. Result of this present study of an existing muffler has been analysed and then compared with vehicle level test observation data. Noise level have been optimized for new muffler design. Other literatures were played significant rule for validate our results.
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Effect of the Friction Coefficient on Clinch Joints
86-90Views:377In 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).
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Parametric Programming Applied to the Optimal Production Structure in Determining
375-389Views:241The agricultural planning often the question arises, how the different input (fertilizer, feed, irrigation, etc) from what to use on a production (land, animals) unit basis, and to what intensity. The input transformational efficiency experiments by setting analysis and evaluation. For example examined the nutrient replenishers fertilization experiments, the effect of nutritional values of the feed on the body weight gain, milk production in animal experiments. The input input efficiency to the external environment (weather, soil conditions, unexpected events), the technology used and the biological factors both influence. The farmer must be chosen in each sector, taking into account the magnitude of these inputs and environmental requirements. The economic optimum is usually trying to approach the sectoral level, which serves as the basis for future planning data. The mathematical programming models using relatively simply and quickly determine the optimal production structure. The models provide the specific resource requirements for, and the limitations of the objective function coefficients are calculated on the basis of sectoral. This becomes a deterministic model, and we can get the appropriate sectoral analyzes outstanding results of production structures. Therefore the relationships within sectors directly incorporate mathematical programming model and corporate interests placed above the interests of the industry to determine the intensity of the sectoral inputs. in their article a fertiliser application example, we present the production structure and the plant production sector fertiliser input of a time optimization, in which the fertilizer for specified sectoral relationships appear in the model objective function.
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Designing Aspects and Classification of Bearing Industry Box Handling Apparatus
325-334Views:253It has been an accepted tendency in the industrial practice since the last third of the 20th Century to decrease the living labour demand of the manufacturing processes. One of the main tools of it is the automation of production. In the design, the construction and the programming of the developed automata, the results of electronics, informatics and mechatronics can be used. All of the scientific fields mentioned above undergo intensive development. By the application of the results achieved in the design of the applications, the monotonous, dangerous and tiresome work not requiring expertise can be assigned to machines. In the longer run, the application of the automata is beneficial also in financial aspect, since the costs of living labour are continuously growing, while that of the mechatronic and technological devices show a rather decreasing tendency. Reliability is also an important aspect. It is well known for everyone that a well-designed and programmed automatic device performs its task without mistakes. If there is any objection or breakdown, on the basis of the currently valid safety technology rules, the machine stops, does not trigger any damage and after its repair, work can be continued.
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Price Analysis Practices in the Pig Sector
1-12Views:312The analysis of sales prices has become a particularly important topic in pig production research, including statistical analysis. With globalisation, we can say that today we are talking about a sector constantly exposed to the effects of the world market. It is also worth pointing out that, compared with other sectors, the impact of external regulation and influence is less pronounced. Thus, the aim of the present research was to identify the journal articles published on the subject of price analysis and, on the basis of these, to establish the correlation with the methodologies often used. It examines the spatial location of price analysis. The results obtained show that the practice of price analysis is mainly carried out in the context of market leading countries, usually on the basis of a cross product chain issue. The research shows the emergence in recent years of increasingly sophisticated methodologies that allow more accurate conclusions to be drawn, while also facilitating planning from a practical point of view.
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Evaluation Opportunities tor Recreational Sport Services – Adapted to Higher Education Environment
150-164Views:384In 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.
