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PurposeThe Premier League (PL) and the Bundesliga (BL) were chosen for this study due to their fundamentally different approaches to ownership regulation and the distribution of media revenues. Regulation in the PL is very liberal if compared to the BL's 50+1-rule. In the BL, the distribution of media revenues is mainly based on past performance, whereas equal distribution is dominant in the PL. The specific aim of this paper was a longitudinal analysis with a focus on the final outcome of the seasons.Design/methodology/approachThis study looks at competitive intensity (CI) in the men's BL and the English PL because it is a crucial indicator for the long-term success of a sports league and the participants. To calculate the CI of both leagues and of all relevant sub-competitions (championship, Champions League (CL), Europa League (EL), Conference League (CoL) and fight against relegation), a CI index (CII) model was generalised and applied for an examination period spanning from 1998/99 to 2020/21.FindingsUntil 2008/09, seasonal CI in the BL was somewhat higher than in the PL. But afterwards, the BL's championship race's CI dropped considerably, while the PL's CI for qualification for the CL rose profoundly. Results also showed that the introduction of the CoL raised the leagues' CI indices.Originality/valueBesides a methodological contribution with the generalisation of the applied CI index model, the findings are discussed in the context of the above-mentioned regulatory and distribution mechanisms also taking into account the very current discussion regarding general regulatory changes within European football.

Research on sustainability and/in sport and, specifically, on the ecological aspects of participatory sporting events is still very scarce despite the recognition these topics have received by actors like, for instance, the European Commission and the United Nations. Against this backdrop, this paper sheds light on a field that is virtually uncharted in academic research, which is the environmental attitudes and willingness to pay for environmental sustainability of participants in participatory sporting events in Europe. In collaboration with the organizer of the Frankfurt Marathon, a study was conducted with a specific focus on German (speaking) marathon runners. In total 1764 data sets were collected with a German (1455 respondents) and an English (309 respondents) online questionnaire. Very insightful descriptive analyses showed that the awareness for the issue of sustainability and sport is still low and that ecological initiatives only have a medium influence on the evaluation of a marathon event. Nevertheless, particularly the German-speaking respondents indicated a high willingness to pay for environmental sustainability in general and for specific measures that can enhance the environmental friendliness of a marathon event, in particular. As will be discussed in the paper, these insights have important managerial implications and are a valuable basis for further research in this evolving field.

PurposeFor managers of sports leagues, it is crucial to produce an attractive competition. For that to happen, it is vital to consider that leagues frequently have more sub-competitions than “just” the championship. In European top football leagues, for instance, four sub-competitions are common (championship, qualification for Champions- or Europa League, avoiding relegation). This paper introduces a new method for measuring competitive intensity (CI) in round-robin sports leagues considering all relevant sub-competitions and applies it to Germany's Bundesliga.Design/methodology/approachThe newly developed model calculates a CI-Index for each sub-competition and the league as a whole. The application to the Bundesliga analyzes its viability and the development of the league's CI over the past 22 seasons.FindingsThe newly introduced CI-Indices prove to be a viable tool for evaluating a league's competitive intensity. The application to the Bundesliga shows that the seasonal CI dropped after 2009/10, which can mainly be attributed to a decline in the championship's CI.Practical implicationsThe results show that it is important to facilitate a high CI in each of Bundesliga's four sub-competitions. Efforts have to be made to ensure that especially the Europa League remains as attractive as possible for the participating teams and their fans because this sub-competition constantly makes the greatest contribution to the seasonal CI.Originality/valueThe new method measures competitive intensity by quantifying the different sub-competitions and their contribution to the seasonal CI. This allows the organizers of sports leagues to assess the intensity of the individual sub-competitions as well as the league as a whole.

Engineered Grinding Tools (EGT) are characterized by a predetermined and controlled arrangement of the abrasive grains. The distribution of the abrasive grains can be used to enhance the grinding process by improving space for coolant supply and for chip removal. This is especially interesting for grinding operations with high specific material removal rates. A numerical method was developed to optimize the grain pattern on EGT. This method consists of a stochastic tool model, a kinematic process model, a material removal model and a grain wear model. The tool model comprehends the relevant geometric properties of the abrasive layer. The material removal model is based on the assumption of a kinematic-geometrical cutting condition. The wear model is based on a grain load limit and the grains’ load is assumed to be proportional to its cutting area. Once the cutting area of one grain exceeds the limit value, wear takes place. The model validation is presented comparing the wear behavior of EGT and workpiece roughness achieved with numerical and experimental methods.

A importância da análise dinâmica nas estruturas atuais tem crescido paralelamente ao surgimento de novas tecnologias construtivas. Com o crescente conhecimento a respeito do comportamento dos materiais e com a otimização de sua utilização, estruturas cada vez mais esbeltas têm sido concebidas e, por conseqüência, suas freqüências fundamentais têm diminuído, aproximando-se da freqüência de cargas dinâmicas oriundas de atividades rítmicas, motores rotativos, movimento de uma torcida em um ginásio. Desse modo, porestar a estrutura sendo solicitada cada vez mais perto da ressonância, os deslocamentos e acelerações ficam intensificados, podendo ultrapassar os limites recomendados e provocando desconforto no usuário. No controle desses problemas, o amortecimento assume grande importância, pois é responsável pela dissipação da energia associada à vibração de uma estrutura. A perda de energia no sistema amortecido acarreta o decaimento da amplitude de vibração, no caso de uma vibração livre, bem como atenua os picos de aceleração e deslocamento da estrutura quando esta é excitada por um carregamentodinâmico. Portanto, com uma boa estimativa para o fator de amortecimento de uma estrutura, otimiza-se o projeto estrutural e garante-se segurança e conforto aos seus usuários. Este trabalho tem como objetivo obter experimentalmente valores para o fator de amortecimento de estruturas e avaliar a confiabilidade da metodologia aplicada. Foram captados os sinais da resposta de três estruturas, oriundos de diversos tipos de ensaios dinâmicos realizados sobre os pisos. Para excitá-los foram utilizados: excitador mecânico, impacto de um corpo de aço solto de certa altura, ensaio heel drop, e pulo de uma pessoa. Utilizando-se filtros digitais, os sinais foram tratados e obtiveram-se, em função do tempo, os gráficos de decaimento da resposta estrutural relativa às principais componentes de freqüência do sinal. Em seguida foram obtidos valores para o fator de amortecimento de cada gráfico, utilizando os métodos do Decaimento Logarítmico, da Meia Amplitude e do Ajuste de Curva. Os mesmos sinais foram representados no domínio da freqüência, e as freqüências fundamentais das estruturas, uma vez determinadas, foram utilizadas como parâmetro para ajustar os modelos numéricos concebidos em programa computacional de elementos finitos. Nowadays, the importance of dynamic analysis on structures has been increasing parallel to new building technologys development. Growing knowledge on materials behavior and the optimization of their use has lead to the construction of even more slender structures. Therefore, structures natural frequencies have been decreasing, approaching to the frequency due to rhythmic activities, industry rotative machines or, for example, stadium crowd movement. Once the structures solicitation is closer to resonance, displacements and acceleration are intensified, which may exceed recommended limits and cause peoples discomfort.Damping has a large importance on controlling this phenomenon, by dissipating the energy associated to structural vibration. Concerning on a free vibration, the energy loss of the damping system causes the vibration amplitude decrease, while attenuates structures displacement and acceleration peaks on forced vibration. Thus, accurate estimation onstructural damping factor provides efficient structural design and offers safety and peoples comfort as well. The aim of this work is to obtain experimental values for structural damping factors and to evaluate the reliability of the applied methodology. Several types of dynamic tests were performed over three structures floors to obtain the structural response. Measurements were done by accelerometers. In order to excite the floors, following tests and devices were used: a mechanical exciter, the impact of a falling steel block, the heel drop test, and the impact of a jumping person. The structural response graphics at the time domain regarding the main natural frequencies were obtained using suitable bandpass filters. Then, damping factor values were obtained using the Logarithmic Decrement Method, the Half Amplitude Method and the Curve Fitting Method as well. These signals were also presented in the frequency domain. Once the structures natural frequencies were defined they were used to fit numeric simulation using finite element software.