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Abstract

The biggest question of professional sports is how to compete successfully in the global economic framework, simultaneously in terms of the sport and in economic terms. As a result, in addition to indicators measuring sports-related effectiveness, the need for an economic analysis of sport has also emerged. Most academic research into the economic aspects of sports are related to the analysis of North American major league sports, as well as to European football. Water polo is also a spectator team sport, yet its economic analysis is almost entirely missing. In this article, we present an economic analysis of the operation of five men’s water polo teams – the top four teams in terms of the sports results and one from the mid-range – competing in the highest-level national championship in Hungary. Our aim is to determine, on the basis of the analysis of the data, the relationship between effectiveness in sports and the economic background of the teams.

It can undoubtedly be concluded that, in addition to appropriate professional decisions, it is the economic situation of a club that has a clear impact on their effectiveness; in other words, up to a certain point, the more disposable funds and wider range of assets a sports company has, the more effectively it can prepare and the better results it will have in the various domestic and international championships and tournaments. CIT (corporate income tax benefits, “TAO” in Hungarian) support is fundamentally important in the field of youth sports development. While professional sports in Hungary are built on the development of junior players, there is still no clear link between the successfulness of the adult and the junior teams. The first-division teams of the clubs providing the best junior players are frequently in the mid-range or occasionally among the weakest teams in the national championship.

Our research has shown that apart from the fact that some teams are extremely successful in the water polo championship, the outcome of many matches becomes quite predictable. Based on these, the uncertainty of the outcome is compromised, and the championship becomes less exciting and also loses some of its audience.

Open access

Abstract

High performance concrete is extensively used for construction works in recent era. For the preparation of high performance concrete (HPC) mineral and chemical admixtures are used. The addition of mineral admixtures minimizes the utilization of cement and makes concrete more sustainable. The addition of metakaolin as a substitute to cement enhances the properties of concrete. There is need to study the mechanical and micro-structural properties of concrete containing metakaolin as cementitious material. In this work an endeavour has been made to study the properties of HPC employing matakaolin as an alternative for cement. The cement has been replaced with metakaolin by 5%, 10%, 15%, 20%, and 25% respectively for 0.25, 0.3, and 0.35 w/c ratios. The strength and electrical resistivity tests are conducted for all concrete mixes on triplicate. Results confirm that the accumulation of metakaolin increases the properties of HPC. A maximum of 49% increase in compressive strength in concrete was observed by the accumulation of 15% of metakaolin in concrete as substitute to cement for 0.25 w/c ratio in comparison to standard concrete. The development of secondary calcium silicate hydrates and minimal Ca(OH)2 components was revealed by X-ray spectroscopy, indicating that the concrete was denser. The results of this study revealed that metakaolin has a considerable impact on high-performance concrete, particularly in terms of compressive and flexural strength.

Open access

Abstract

Shape memory alloys are smart materials which have remarkable properties that promoted their use in a large variety of innovative applications. In this work, the shape memory effect and superelastic behavior of nickel-titanium helical spring was studied based on the finite element method. The three-dimensional constitutive model proposed by Auricchio has been used through the built-in library of ANSYS® Workbench 2020 R2 to simulate the superelastic effect and one-way shape memory effect which are exhibited by nickel-titanium alloy. Considering the first effect, the associated force-displacement curves were calculated as function of displacement amplitude. The influence of changing isothermal body temperature on the loading-unloading hysteretic response was studied. Convergence of the numerical model was assessed by comparison with experimental data taken from the literature. For the second effect, force-displacement curves that are associated to a complete one-way thermomechanical cycle were evaluated for different configurations of helical springs. Explicit correlations that can be applied for the purpose of helical spring's design were derived.

Open access

Abstract

Composite materials are granted first choice in the present manufacturing scenario due to their compatibility with tolerances up to 0.001 mm and lower weight. The research design works on the composites of the metal matrix, which are used primarily for aeronautical and industrial applications. Metal matrix composites are being used extensively in structural engineering. Silicon carbide and fly shell ash were used as compliance in aluminium alloys for the manufacture of metal matrix composites (LM13). The composite metal matrix is created employing Stir Casting method. When compared to open moulding, closed moulding, and cast polymer moulding, it is a less expensive and more effective method. The composites produced were then examined for mechanical properties, from the results it was found that the presence of ash and ceramic grains can adversely impact the properties of the composites and even make them brittle. It is time to change the mechanical properties of aluminium by creating hybrid composites with double and often triple-reinforced sections. Hybrid composites have greater performance, better tolerance to tear, low density, resistance to corrosion and strong rigidity over metal matrix composites. In this research an Al-Sic-fly ash composite is proposed and the mechanical properties of hardness, tensile strength, corrosion strength, micro structure analysis are investigated.

Open access

Abstract

The aim of the thesis is the geometric design, CAD modelling and TCA of spur gear pairs having normal teeth based on the modification of the pressure angle. The first task is the geometric design and CAD modelling of the gear pairs (5 pairs are designed) where only the pressure angle is modified beside the constancy of the other initial parameters. The second task is to analyse the comparison possibility and the accuracy similarity of the 2D and the 3D models by the Hertz (equivalent) stress analysis. Finally, I give analysis of the maximum equivalent stress, normal stress and contact pressure for each pair while three teeth are rolling down on each other.

Open access

Abstract

Laminated composite shell panels take part in several engineering structures. Due to their complex nature, failure modes in composites are highly dependent on the geometry, direction of loading and orientation of the fibers. However, the design of composite parts is still a delicate task because of these fiber failure modes, which includes matrix failure modes or other so-called interlaminar interface failure such as delamination, that corresponds to the separation of adjacent layers of the laminate as a consequence of the weakening of interface layer between them. In this work, impact-induced delamination represented as a circular single delamination is investigated, as it can reduce greatly the structural integrity without getting detected. Furthermore, attention is focused on its effect upon the post-buckling response and the compressive strength of a composite panel. The delamination buckling was modelled using the cohesive element technique under Abaqus software, in order to predict delamination growth and damage propagation while observing their effects on the critical buckling load.

Open access

Abstract

Laminated composite shell panels take part in several engineering structures. Due to their complex nature, failure modes in composites are highly dependent on the geometry, direction of loading and orientation of the fibers. However, the design of composite parts is still a delicate task because of these fiber failure modes, which includes matrix failure modes or other so-called interlaminar interface failure such as delamination, that corresponds to the separation of adjacent layers of the laminate as a consequence of the weakening of interface layer between them. In this work, impact-induced delamination represented as a circular single delamination is investigated, as it can reduce greatly the structural integrity without getting detected. Furthermore, attention is focused on its effect upon the post-buckling response and the compressive strength of a composite panel. The delamination buckling was modelled using the cohesive element technique under Abaqus software, in order to predict delamination growth and damage propagation while observing their effects on the critical buckling load.

Open access

Abstract

In the first and second chapter the article provides an overview of the currently used energy sources in Hungary and the most popular renewable energies. In addition, the Weibull estimation is presented, too. The subsequent chapter looks at some of the research results about the solar energy optimization with Weibull distribution. The study presented is a mathematical solution of the solar energy optimization with distribution. The final chapter contains a brief explanation of the results. This publication briefly summarizes a prototype solution for an estimation and forecast of solar energy and yield with Weibull distribution.

Open access

Abstract

This paper deals with the disturbance rejection, parameter uncertainty cancelation, and the closed-loop stabilization of the water level of the four-tank nonlinear system. For the four-tank system with relative degree one, a new structure of the active disturbance rejection control (ADRC) has been presented by incorporating a tracking differentiator (TD) in the control unit to obtain the derivate of the tracking error. Thus, the nonlinear-PD control together with the TD serves as a new nonlinear state error feedback. Moreover, a sliding mode extended state observer is presented in the feedback loop to estimate the system's state and the total disturbance. The proposed scheme has been compared with several control schemes including linear and nonlinear versions of ADRC techniques. Finally, the simulation results show that the proposed scheme achieves excellent results in terms of disturbance elimination and output tracking as compared to other conventional schemes. It was able to control the water levels in the two lower tanks to their desired value and exhibits excellent performance in terms of Integral Time Absolute Error (ITAE) and Objective Performance Index (OPI).

Open access

Abstract

This paper deals with the disturbance rejection, parameter uncertainty cancelation, and the closed-loop stabilization of the water level of the four-tank nonlinear system. For the four-tank system with relative degree one, a new structure of the active disturbance rejection control (ADRC) has been presented by incorporating a tracking differentiator (TD) in the control unit to obtain the derivate of the tracking error. Thus, the nonlinear-PD control together with the TD serves as a new nonlinear state error feedback. Moreover, a sliding mode extended state observer is presented in the feedback loop to estimate the system's state and the total disturbance. The proposed scheme has been compared with several control schemes including linear and nonlinear versions of ADRC techniques. Finally, the simulation results show that the proposed scheme achieves excellent results in terms of disturbance elimination and output tracking as compared to other conventional schemes. It was able to control the water levels in the two lower tanks to their desired value and exhibits excellent performance in terms of Integral Time Absolute Error (ITAE) and Objective Performance Index (OPI).

Open access