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81.
Charles Perrow used the term “normal accidents” to characterize a type of catastrophic failure that resulted when complex, tightly coupled production systems encountered a certain kind of anomalous event. These were events in which systems failures interacted with one another in a way that could not be anticipated, and could not be easily understood and corrected. Systems of the production of expert knowledge are increasingly becoming tightly coupled. Unlike classical science, which operated with a long time horizon, many current forms of expert knowledge are directed at immediate solutions to complex problems. These are prone to breakdowns like the kind discussed by Perrow. The example of the Homestake mine experiment shows that even in modern physics complex systems can produce knowledge failures that last for decades. The concept of knowledge risk is introduced, and used to characterize the risk of failure in such systems of knowledge production.  相似文献   
82.
The biomechanical profile of high-level endurance runners may represent a useful model that could be used for developing training programmes designed to improve running style. This study, therefore, sought to compare the biomechanical characteristics of high-performance and recreational runners. Kinematic and kinetic measurements were taken during overground running from a cohort of 14 high-performance (8 male) and 14 recreational (8 male) runners, at four speeds ranging from 3.3 to 5.6?m?s?1. Two-way ANOVA analysis was then used to explore group and speed effects and principal component analysis used to explore the interdependence of the tested variables. The data showed the high-performance runners to have a gait style characterised by an increased vertical velocity of the centre of mass and a flight time that was 11% longer than the recreational group. The high-performance group were also observed to adopt a forefoot strike pattern, to contact the ground with their foot closer to their body and to have a larger ankle moment. Importantly, although observed group differences were mostly independent of speed, the tested variables showed a high degree of interdependence suggesting an underlying unitary phenomenon. This is the first study to compare high-performance and recreational runners across a full range of kinematic and kinetic variables. The results suggest that high-performance runners maintain stride length with a prolonged aerial phase, rather than by landing with a more extended knee. These findings motivate future intervention studies that should investigate whether recreational runners could benefit from instruction to decrease shank inclination at foot contact.  相似文献   
83.
The French Football Federation was the first football governing body to put in place, in 1990, a financial regulation system. It might be expected that UEFA’s Financial Fair Play (FFP) system established in 2010 would be similar to French DNCG (National Direction for Management Control) regulations. However, while FFP is concerned with profitability, DNCG is focused on solvency. Hence, a French club may be loss-making and not compliant with FFP, while at the same time being solvent in accordance with DNCG rules. Our research confirms that most French clubs do not conform to FFP rules. As such, it provides further evidence that DNCG has not prevented poor financial management within French clubs. The coexistence of DNCG and FFP– or any other domestic financial regulation and FFP –may result in disparities between domestic clubs. As a consequence, there should be consistent financial regulation in all European leagues.  相似文献   
84.
The proliferation of new biomechanical technology in laboratory and field settings facilitates the capture of data-sets consisting of complex time-series. An understanding of the appropriate statistical approaches for analysing and interpreting these data-sets is required and the functional data analysis (FDA) family of statistical techniques has emerged in the biomechanical literature. Given the use of FDA is currently in its infancy with biomechanical data, this paper will form the first of a two part series aiming to address practical issues surrounding the application of FDA techniques in biomechanics. This work focuses on functional principal components analysis (fPCA), which is explored using existing literature and sample data from an on-water rowing database. In particular methodological considerations for the implementation of fPCA such as temporal normalisation of data, removal of unwanted forms of variation in a data-set and documented methods for preserving the original temporal properties within a set of curves are explored in detail as a part of this review. Limitations and strengths of the technique are outlined and recommendations are provided to encourage the appropriate use of fPCA within the field of applied sports biomechanics.  相似文献   
85.
ABSTRACT

How do ideas become policies? What route do they take from inception to implementation and what criteria are used to evaluate one set of proposals against another? This paper examines the development of the Creative Work Fellowship policy proposal in Limerick, tracing the origins of the idea, itself a contended and negotiated object, from discussions between academics and policy-makers through to scoping, pitching and scaling the policy to its eventual users. This policy idea was designed during the Intelligence Unit (IU) commissioned by Limerick2020 as part of the city’s bid to become European Capital of Culture in 2020. The IU took the form of a policy think-tank, tasked with generating insights, ideas and policy proposals into the place of culture within Limerick city and region. The IU structure created a set of actors and an epistemic community capable of both generating and using ideas effectively, chiefly through two mechanisms. The first involved a robust critique and rebuilding process that every element of the policy was exposed to; the second involved feedback from interested parties at specific stages in the process. This created a series of “policy entrepreneurs” capable of taking a fully costed and modelled policy suggestion to government. The findings presented in the paper include an analysis of the collaborative nature of this policy development process, Based on this framework, we also consider the role of the European City of Culture bid process as catalyst for policy development in a regional context, and present findings on this subject.  相似文献   
86.
87.
Fishing tournaments are a common feature in recreational angling across a wide range of target species in both fresh and salt waters. Tournaments are organised for a number of purposes, including as commercial enterprises; as fund-raising initiatives for angling clubs; for economic development purposes (e.g. tourism); as well as improve participants' skill levels. Most tournaments are confined to geographically small areas and usually occur over a small number of days, which can mean a pulse of economically significant activity in the local area. This paper analyses the nature of expenditure associated with angling tournaments, including travel, food and accommodation, and angling-related expenditures as a function of socio-economic and angler characteristics. Analysis based on 106 tournaments across Ireland during 2013 finds a clear 80/20 segmentation between ‘high’- and ‘low’-spend anglers and that the segmentation occurs across all fish target species considered. The analysis also finds that British coarse anglers participating at Irish angling tournaments spend considerably more than other anglers irrespective of target species or angler country of origin.  相似文献   
88.
ABSTRACT

This article analyses the near-impossibility, for the duration of the amateur-professional divide, of cricketers born into working-class families being admitted to amateur status and, thus, to county captaincy, in the English first-class game. Its principal argument is that the hegemony achieved in the latter half of the nineteenth century by the English upper class (the aristocracy, major landowners and leaders of financial capital and their families) had one of its most visible manifestations in the culture of first-class cricket. The hegemony of this group (represented by the Marylebone Cricket Club) was sustained by a specific myth of amateurism that was rooted in caste-like social relations. By the late 1930s these relations had become unsustainable and hegemony was maintained by a subtle and unacknowledged switch to relations of class. The article charts this process, using four case studies of working-class professional cricketers, each of which brought the ideological reality of the amateur myth into sharp relief.  相似文献   
89.
The current study compared changes in neuromuscular control between slackline training and the stabilization training elements of the FIFA 11+ programme. Twenty-five students in 2 groups performed a 12-unit training programme. The slackline training group (n?=?13) exclusively trained with a slackline. The stabilization training group (n?=?12) practised exercises as described in the second part of the FIFA 11+ programme. Improvements in balance were assessed using three tests for dynamic, quasi-static, and perturbed postural control: the star excursion balance test (SEBT), the closed-eye single-leg stance, and the MFT S3-Check. Both groups significantly improved the stability and sensorimotor index of the MFT S3-Check (p?<?.001), their range on the SEBT (p?<?.001), and the duration of closed-eye single-leg stance (p?<?.001). The group?×?training interaction was significant for the MFT S3-Check (stability index: p?=?.042; sensorimotor index: p?=?.004) and the SEBT (dominant leg: p?=?.003; averaged both legs: p?=?.016), with the slackline training group showing a larger training effect than the stabilization training group. The results of the present study suggest that slackline training offers similar – or better – improvements in neuromuscular control as the FIFA 11+ warm-up programme. If compliance with the FIFA 11+ programme is declining, then slacklining might offer an alternative approach to reach the training goals of improved sensorimotor control.  相似文献   
90.
Analytical methods to assess thigh muscle balance need to provide reliable data to allow meaningful interpretation. However, reproducibility of the dynamic control ratio at the equilibrium point has not been evaluated yet. Therefore, the aim of this study was to compare relative and absolute reliability indices of its angle and moment values with conventional and functional hamstring–quadriceps ratios. Furthermore, effects of familiarisation and angular velocity on reproducibility were analysed. A number of 33 male volunteers participated in 3 identical test sessions. Peak moments (PMs) were determined unilaterally during maximum concentric and eccentric knee flexion (prone) and extension (supine position) at 0.53, 1.57 and 2.62 rad · s–1. A repeated measure, ANOVA, confirmed systematic bias. Intra-class correlation coefficients and standard errors of measurement indicated relative and absolute reliability. Correlation coefficients were averaged over respective factors and tested for significant differences. All balance scores showed comparable low-to-moderate relative (<0.8–0.9) and good absolute reliability (<10%). Relative reproducibility of dynamic control equilibrium parameters augmented with increasing angular velocity, but not with familiarisation. At 2.62 rad · s–1, high (moment: 0.906) to moderate (angle: 0.833) relative reliability scores with accordingly high absolute indices (4.9% and 6.4%) became apparent. Thus, the dynamic control equilibrium is an equivalent method for the reliable assessment of thigh muscle balance.  相似文献   
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