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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

Rekonstrukció, újrafelhasználás és bontás •

1945 utáni modern épületek sorsa a műemlékvédelem körein kívül és belül

Reconstruction, Reuse and Demolition •

The fate of post World War II modern buildings outside and inside the realm of monument protection
Építés - Építészettudomány
Author:
Gergely Hartmann

Az 1945 utáni modern épületek sorsa ma különösen problémás. A hazai műemlékes és építész szakma egy része, a nemzetközi szaktekintélyekkel egyidőben, már a kilencvenes évek elején felfigyelt arra, hogy különleges, a hagyományos műemléki rekonstrukcióktól eltérő hozzáállást kíván megújításuk. A kétezres évek eleje óta azonban átfogó, szintetizáló kutatás itthon nem történt, és (a szocreál épületekkel nem számolva) csak néhány 1951 előtti épület vitatott műemléki rekonstrukciójára került sor. A hazai intézményes műemlékvédelem még a 2010 előtti időszakban sem tudott módszertani szempontból megújulni. Ennek akadálya nem elsősorban szakmai, inkább a döntéshozói akarat hiánya volt. Példákkal illusztrálom, hogy Nyugat- Európában eközben milyen eredményeket értek el a modern épületeknek – elsősorban a hatvanas évek épületeinek – felújítása területén, és ennek kontextusába helyezem a hazai helyzetet.

Miközben itthon a hivatalosan védett, II. világháború utáni épületek legtöbbje pusztul, a védelem körein jórészt kívül esők újrahasznosítására számos példát találunk. Az adaptive reuse (alkalmazkodó, rugalmas újrafelhasználás) a nemzetközi építészeti színtér egyik legkurrensebb témája az utóbbi évtizedben. A fogalom több lehetséges értelmezése közül tanulmányomban leginkább úgy tekintek rá, mint az építészet, a belsőépítészet és az örökségvédelem egyfajta metszetére,1 szem előtt tartva, hogy ez a fajta alkotói hozzáállás magában hordozza az újrahasznosítás fenntarthatósági és környezetvédelmi aspektusait is. A 2008-as gazdasági világválság után, de kiemelten 2015 körültől megfigyelhetjük a hazai, 1945 utáni épületállománnyal foglalkozó reuse-projektek számának, valamint az ezekre irányuló figyelemnek a növekedését. Új lendületet kapott és új szereplőkkel gazdagodott az e korszak örökségéről szóló párbeszéd is – igaz egy szűkebb szakmai közeg kereteit továbbra sem lépi át. A rekonstrukciók mellett kiemelt hangsúlyt kapott az újrahasznosítás fontossága az egyre fokozódó klímaválság kihívásaira is reagálva.

Az intézményes védelemtől függetlenül létrejött hazai újrahasznosítási projektek közül vannak példamutatók, vitathatók és pusztítók is. Konkrét eseteket mutatok be vázlatosan, amiből, ha átfogó folyamatok nem is, de tendenciák kirajzolódhatnak. Az ezekben való eligazodást rövid kritikai elemzések segítik.

A példák sora mutatja, hogy „szerves” folyamatként is megindult a megújulás, ugyanakkor az örökség jórészt védtelen a mindenkori politika és a beruházók esetleges romboló szándékától. Amennyiben hiányzik az intézményes, de differenciáló, többszintű és rugalmas örökségvédelem, a felújítások sikere az egyes építészek és megbízóik ízlésén és szubjektív döntésein múlik.

The fate of modern buildings built after 1945 is particularly problematic today. Some of the Hungarian architects and experts of the built heritage, at the same time as international professionals, noticed in the early 1990s that their renewal required a special attitude different from traditional reconstructions of the monuments. However, since the early 2000s, no comprehensive, synthesizing research has taken place, and only a few modern buildings built before 1951 have undergone controversial monumental reconstructions. The institutional protection of monuments in Hungary could not be renewed from a methodological point of view, even in the period before 2010. The obstacle to this was not primarily professional, but rather a lack of the will of the decision-makers. I illustrate with examples the results achieved in Western Europe in the field of reconstruction and reuse of modern buildings, especially from the sixties, and I place the Hungarian situation in the context of this.

While in Hungary the officially protected post-World War II buildings are perishing, there are many examples of the recycling-architecture and reuse of those which are largely outside the scope of defense. Adaptive reuse is one of the most pressing themes of the international architectural level in the last decade.

Dealing with the post-war building after the 2008 world economic crisis, and especially around 2015, we can observe an increase in the number of Hungarian reuse projects and the attention paid to them. The dialogue on the legacy of this era has also gained new impetus and new actors joined it – although it still does not go beyond a narrower professional environment. In addition to historical reconstructions, emphasis was placed on the importance of reuse in response to the challenges of the growing climate crisis.

Dealing with the Hungarian building stock after 1945 was again thematized by a young generation of architects after the 2008 global economic crisis, but especially from around 2015, in a more complex way (social, economic, cultural, political, etc.). In addition to reconstructions, the importance of recycling in response to the challenges of the growing climate crisis was also highlighted.

Regardless of institutional protection, recycling projects have proliferated in Hungary in the last decade. Some of them are exemplary, but many of them are debatable, or even destructive. I outline specific cases from which comparison general trends can emerge. Orientation in these is aided by brief critical analyses. A series of examples show that the renewal has begun as an “organic” process, but at the same time the heritage is largely unprotected from current politics and the potentially destructive intentions of investors. In the absence of an institutional but at the same time differentiating, multi-level and flexible heritage protection, the success of renovations depends on the tastes and subjective decisions of individual architects and their clients.

Restricted access
Pollack Periodica
Authors:
Marek Csóka
,
Ivana Marko
,
Gergely Rózsa
, and
Štefan Stanko

Abstract

The goal of this work is the hydraulic capacity assessment of selected combined sewer systems in the city of Trnava. The selected sewer system constitutes from 160 sections 3.3 km long. Hydraulic capacity assessment will test sewer system, created in SeWaCAD program with design rainfall events with varied frequencies. The result of assessment showed that hydraulic capacity of combined sewer system did not meet requirements to properly work. Malfunctioning sewer pipelines must be changed. Design rain with frequency at least one in two years will be used as restoration model.

Restricted access

Understanding Centrality Theories •

Socio-spatial Characteristics and Interrelations of City Centers

Városközpont-elmélet•

A városközpontok, alközpontok téri és társadalmi jellemzői
Építés - Építészettudomány
Authors:
Anna Kornélia Losonczy
and
Annamária Orbán

The study is based on the re-combination or synthesis of international scientific literature, and the definition of the notions center, and sub-center. A conceptual-structural framework of socio-spatial characteristics of centers (and sub-centers) is set up, these factors are essential elements of making, maintaining, and rehabilitating a city: Market and Competition; Node and Pole; Faith; Power; Security; Mixture; and Identity. In an evaluation matrix, the meta-physical characteristics (that are the determining factors of the physical attributes) of these archetypes are drawn. Based on famous theorists, three types of city forms are distinguished: the “traditional / organic”, the “modern / planned”, and the “contemporary / disjointed” ones. We argue that the historical, theoretical-conceptual background of the triple division is comprehensible. However, this trichotomy lacks some essential elements, “measurable” aspects of city centers – outlined in our study –, which are important in contemporary urban processes and support more realistic urban planning.

Tanulmányunkban – nemzetközi szakirodalmi kutatás alapján – definiáljuk a központ és az alközpont fogalmakat. Meghatározzuk a központok (és az alközpontok) téri-társadalmi jellemzőinek konceptuális és strukturális keretrendszerét. Ezek az alkotóelemek – Piac és Verseny; Csomópont és Pólus; Hit; Hatalom; Biztonság; Vegyesség; Identitás – a város alapításának, fenntartásának és megújításának feltételei. Egy értékelő mátrix segítségével összegezzük ezen archetípusok metafizikai jellemzőit, és amellett érvelünk, hogy ezek determinálják a központok fizikai tulajdonságait. Elismert szerzőkre hivatkozva ismertetjük a legelfogadottabb városmodellek hármas felosztását: a hagyományos / organikus, a modern / tervezett és a kortárs / széttagolt tipológiát. Azt állítjuk, hogy a hármas felosztás történelmi, elméleti-konceptuális háttere megalapozott. Ugyanakkor ez a hármasság nem foglalja magában azokat a „mérhető” – a tanulmányban felvázolt – szempontokat, amelyek segítségével a valósághoz jobban közelítő, a tervezési gyakorlatban könnyebben alkalmazható központmodellek vázolhatók fel.

Open access

Abstract

Transmission congestion issues became more severe and difficult to control as the power sector became more deregulated. The grey wolf optimization algorithm is proposed to relieve congestion by rescheduling generation effectively, resulting in the least congestion cost. The selection of participating generators is based on sensitivity, and the proposed technique is used to determine the best-rescheduled output active power generation to minimize line overload. The IEEE-30 bus system is used to test the proposed optimization technique. It has been demonstrated that when compared to other algorithms like the real coded genetic algorithm, particle swarm optimization, and differential evolution algorithm, the proposed approach produces excellent results in terms of congestion cost.

Restricted 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