An examination of the Clegg impact hammer test with regard to the playing performance of synthetic sports surfaces     

M.?J.?CarréEmail author  S.?J.?Haake 《Sports Engineering》2004,7(3):121-129

One of the tests used to evaluate the performance of sports surfaces measures the peak deceleration of a rigid mass during contact with the surface, after being dropped from a set height. It is widely used and is included in a number of international standards. The test was carried out using two drop heights on four different designs of artificial cricket pitch, with a full set of acceleration data being collected over the duration of impact. These data were then integrated twice with respect to time to produce velocity and displacement information. Oblique impacts of cricket balls were also carried out and analysed using a high-speed video system to evaluate the playing performance of each pitch design. It was found that, although the pitches gave quite different readings of peak deceleration, they produced similar values for coefficient of restitution and were therefore considered to ‘play’ in a very similar way. This was due to a high peak deceleration reading being accompanied by a short contact time and low peak deceleration being accompanied by a long contact time, meaning that the change in momentum was similar in both cases. It was concluded that for accelerometer tests to be useful, all the acceleration-time data should be analysed, rather than the peak value alone.  相似文献   

影响顾客行为的满意度     

MagnusS&#;derlund  牧平 《出版经济》2004,(6):37-37

今天,在企业经营中,顾客满意度已成为一个十分敏感的话题.从企业角度来看,顾客满意与否,同顾客各种各样的行为相关联,一个顾客满意,该顾客的忠诚度得以提高,同时该顾客可能向其他顾客推荐企业的产品或服务. 分析研究表明,顾客满意度的变化幅度不大.顾客满意度更趋向于极端,要么十分满意,要么非常不满意.  相似文献   

Firefighting training at a distance – a longitudinal study     

R. Holmgren  U. Haake  T. Söderström 《Journal of Vocational Education & Training》2019,71(1):65-86

This article presents an analysis of a five-year study on the implementation of a technology-supported distance programme in Swedish firefighter training. Based on activity theory and four interview studies, the attention is directed to firefighter instructors’ perceptions and use of digital technologies with a focus on challenges, contradictions and changes. Two phases are identified, viz an implementation phase and a dissemination phase. During the implementation phase a clear contradiction emerges regarding how the object of the training should be interpreted, which results in the instructors responsible for the implementation reconsidering previous beliefs and, with the support of digital technologies, developing more theoretical and process-oriented approaches and improving the course design. However, during the dissemination phase, when all instructors are involved, a number of conflicts and dilemmas emerge, resulting in the changes achieved in the distance programme to some extent being normalised in the direction of the instructor-centred and exercise-oriented approaches of the campus programme. The article concludes with a discussion about contradictions as well as opportunities that may emerge during the implementation process of a vocational technology-supported distance programme.  相似文献   

An improvement index to quantify the evolution of performance in field events     

Steve Haake  David James  Leon Foster 《Journal of sports sciences》2015,33(3):255-267

The mean of the top 25 performances in 8 men’s and 5 women’s field events since the 1890s showed that performances increased dramatically after the Second World War II and subsequently plateaued during the late twentieth century. A performance improvement index, developed on the basis of work done, was set to 100% in 1948. The underlying rise found in all events was modelled using an exponential function with a superposition of steps and linear changes to account for the introduction of rule changes, drugs testing and the introduction of new technologies. The performance improvement index in throwing events increased to 140.9% compared with 125.8% in jumping events, and women’s performance improvement always exceeded that of men’s. Around half of all events were shown to have reached 99.9% of their predicted limit with a majority reaching it within the next 25 years. It was concluded that performance will only change in the future if an intervention takes place: this could be the emergence of a new technology, a rule change or a new athlete population.  相似文献   

Bottom-up versus top-down policies towards the commercialization of university intellectual property   总被引：1，自引：0，他引：1  

Brent Goldfarb  Magnus Henrekson 《Research Policy》2003,32(4):639-658

What national policies are most efficient in promoting the commercialization of university-generated knowledge? We address this question by characterizing and evaluating the policy pursued in Sweden and the US, two countries that put a great deal of resources into university R&D, but follow very different models for commercialization. Despite a leading academic record, there is an impression of laggard rates of commercialization of academic research results in Sweden. Although there exist no micro data to evaluate this impression, we argue that it is likely to be true in part due to the top-down nature of Swedish policies aimed at commercializing these innovations as well as an academic environment that discourages academics from actively participating in the commercialization of their ideas. This sits in stark contrast to a US institutional setting characterized by competition between universities for research funds and research personnel, which in turn has led to significant academic freedoms to interact with industry, including significant involvement in new firms.  相似文献   

Reckoning the Shape of Everything: Underdetermination and Cosmotopology     

Magnus  P. D. 《The British journal for the philosophy of science》2005,56(3):541-557

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Doing Leadership in Higher Education: The gendering process of leader identity development     

Ulrika Haake 《Tertiary Education and Management》2013,19(4):291-304

How leadership is done in higher education is analysed through a longitudinal interview study among the heads of department at a Swedish university. The focus is directed towards the construction and reconstruction of leader identity from the time when the heads were novices up until four years later when they were more experienced. The main result is the emergence of a gendering process in the discourse on academic leadership. At the end of the leadership assignment period, male and female department heads did not ever share the same subject positions and leader identity was described in differing terms in subject positions held by women and men, respectively. Three common identity development processes emerged: a vague development process where a non‐head of department identity was strong over time (men), a process towards a positive and clear manager identity (men), and a process towards a gender‐focused and problem‐oriented leader identity (women).  相似文献   

Factorial Validity and Invariance Testing of the Exercise Dependence Scale-Revised in Swedish and Portuguese Exercisers     

Magnus Lindwall  Antonio Palmeira 《Measurement in physical education and exercise science》2013,17(3):166-179

The present study investigated the factorial validity and factorial invariance of the 21-item Exercise Dependence Scale-Revised using 162 Swedish and 269 Portuguese exercisers. In addition, the prevalence of exercise dependence symptoms and links to exercise behavior, gender, and age in the two samples was also studied. Confirmatory factor analyses demonstrated that the hypothesized 7-factor model made a good fit to data in both samples. Multi-sample analyses supported partial measurement invariance across the samples; only factor loadings involving items 3 and 19 were noninvariant. The “Reduction in Other Activities” and “Lack of Control” factors were the most problematic scales in terms of average variance explained and reliability measures of weighted omega and Cronbach's alpha. In total, 9.2% of the Swedish sample and 5.2% of the Portuguese sample were classified as at risk for exercise dependence. Overall, the results support the factorial validity of the translated Exercise Dependence Scale-Revised in samples outside North-America, although more research is needed.  相似文献   

Maximal oxygen uptake versus maximal power output in children     

Magnus Dencker  Ola Thorsson  Magnus K. Karlsson  Christian Lindén  Per Wollmer  L. B. Andersen 《Journal of sports sciences》2013,31(13):1397-1402

Abstract

Maximal oxygen uptake ([Vdot]O_2max) is considered the optimal method to assess aerobic fitness. The measurement of [Vdot]O_2max, however, requires special equipment and training. Maximal exercise testing with determination of maximal power output offers a more simple approach. This study explores the relationship between [Vdot]O_2max and maximal power output in 247 children (139 boys and 108 girls) aged 7.9–11.1 years. Maximal oxygen uptake was measured by indirect calorimetry during a maximal ergometer exercise test with an initial workload of 30 W and 15 W · min^?1 increments. Maximal power output was also measured. A sample (n = 124) was used to calculate reference equations, which were then validated using another sample (n = 123). The linear reference equation for both sexes combined was: [Vdot]O_2max (ml · min^?1) = 96 + 10.6 · maximal power + 3.5 · body mass. Using this reference equation, estimated [Vdot]O_2max per unit of body mass (ml · min^?1 · kg^?1) calculated from maximal power correlated closely with the direct measurement of [Vdot]O_2max (r = 0.91, P <0.001). Bland-Altman analysis gave a mean limits of agreement of 0.2±2.9 (ml · min^?1 · kg^?1) (1 s). Our results suggest that maximal power output serves as a good surrogate measurement for [Vdot]O_2max in population studies of children aged 8–11 years.  相似文献   

The Dynamics of Professional Identity     

Magnus Fredriksson 《Journalism Practice》2014,8(5):585-595

The aim of this article is to analyse how journalists' professional identity is related to their attitude towards PR. The focus is how—and to what extent—journalistic ideology, organizational belonging and the individual's social position influence journalists' perception that other journalists working with PR lower the trustworthiness of journalism. The analyses rest on data from the Swedish Journalist Survey 2011, which is a national representative survey of Swedish journalists. The results show that journalists in general embrace a hostile attitude towards journalists who start working as PR practitioners. However, those who have worked as a journalist for fewer years or have journalistic ideals promoting the amusement function of journalism, or have worked as a freelance, or been employed in an organization producing newsletters, as well as female journalists, weaken this posture. The article concludes with a discussion on how the results could be understood in relation to recent changes in journalism's power and prerequisites, and how a professional identity might function as a form of resistance.  相似文献