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21.
Ross P. Garner 《Popular Communication》2016,14(2):86-98
This article employs autoethnographic reflections to contribute towards debates concerning film-induced tourism by analysing the officially endorsed Doctor Who Experience Walking Tour around filming locations from the BBC series in Cardiff Bay, Wales. Approaching this tour as an example of paratextuality, the article pursues two arguments. First, it reflects upon the attempts used within the tour for encouraging connection between participants and the locations visited from the perspective of immersion. However, noting preceding positions, it is recognized that the tour constructs forms of imaginative immersion. The terms symbolic and cued immersion are subsequently introduced to consider the strategies that the tour employs to position fans and engage them with its frequently quotidian spaces. Second, the article explores the links between the tour’s immersive strategies and its institutional context, arguing that these assist in reinforcing core brand values regarding BBC Worldwide. 相似文献
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Benjamin Kane Williams Ross H. Sanders Joong Hyun Ryu Pitre C. Bourdon Philip Graham-Smith Peter J. Sinclair 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(2):202-214
Magnetic-inertial measurement units (MIMUs) are becoming more prevalent in sports biomechanics and may be a viable tool to evaluate kinematic parameters. This study examined the accuracy of a MIMU to estimate orientation angles under static conditions and dynamically from a squash racket during a forehand drive shot. A MIMU was mounted onto a goniometer and moved through 0–90°, with static data collected at 10° increments during 10 repetitions of all three axes. Typical error analyses showed the MIMU to be very reliable (TE ≤ 0.03°). MIMU accuracy was determined via intraclass correlation coefficients (ICC) (r > 0.999, p < 0.001). An ordinary least products regression showed no proportional bias and minimal fixed bias for all axes. Dynamic accuracy was assessed by comparing MIMU and optical motion capture data of squash racket swing kinematics. A MIMU was fixed onto a racket and 10 participants each hit 10 forehand shots. Mean orientation angle error at ball impact was <0.50° and ICC showed very high correlations (r ≥ 0.988, p < 0.001) for all orientations. Swing phase root mean squared errors were ≤2.20°. These results indicate that a MIMU could be used to accurately and reliably estimate selected racket swing kinematics. 相似文献
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Sam Robertson Bart Spencer Nicole Back Damian Farrow 《Journal of sports sciences》2019,37(11):1280-1285
Representative learning design provides a framework for the extent to which practice simulates key elements of a performance setting. Improving both the measurement and analysis of representative learning design would allow for the refinement of sports training environments that seek to replicate competition conditions and provide additional context to the evaluation of athlete performance. Using rule induction, this study aimed to develop working models for the determination of high frequency, representative events in Australian Rules football kicking. A sample of 9005 kicks from the 2015 Australian Football League season were categorised and analysed according to the following constraints: type of pressure, kick distance, possession source, time in possession, velocity and kick target. The Apriori algorithm was used to develop two models. The first consisted of 10 rules containing the most commonly occurring constraint sets occurring during the kick in AF, with support values ranging from 0.15 to 0.22. None of the rules contained more than three constraints and confidence values ranged from 0.63 to 0.84. The second model considered ineffective and effective kick outcomes and displayed 70% classification accuracy. This research provides a measurement approach to determine the degree of representativeness of sports practice and is directly applicable to various team sports. 相似文献
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Nicholas Tam Devon R. Coetzee Safwaan Ahmed Robert P. Lamberts Yumna Albertus-Kajee Ross Tucker 《European Journal of Sport Science》2017,17(9):1220-1229
Introduction: Many factors may contribute to running-related injury. These include fatigue and footwear, the combination of which has rarely been studied, in particular with reference to barefoot running, recently advocated as a method to reduce injury risk. Methods: Twenty-two runners (12 well-trained and 10 trained) participated in a 10?km fatiguing trial. Knee and ankle joint kinematics and kinetics and electromyography were assessed during overground running in the barefoot and shod condition. This was performed pre- and post-fatigue using a motion capture system and force platforms. Results: Initial loading rate increased in the trained runners when barefoot but not shod. Shod knee stiffness increased in both groups after fatigue, whereas barefoot knee stiffness decreased only in the trained group. A reduction in barefoot bicep femoris pre-activation was found in both groups. During stance, a reduction in vastus lateralis and biceps femoris and an increase in tibialis anterior activity were found over time in both groups and conditions. Trained runners decreased gluteus medius and increased lateral gastrocnemius median frequency for both conditions after fatigue. Conclusion: When fatigued, gait adjustments in habitually shod runners may increase injury risk when running barefoot. Training status may be a risk factor for injury, as less-trained runners experience muscular fatigue changes that may compromise ground reaction force attenuation. Caution is recommended when transitioning to pure barefoot running. 相似文献
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This article presents findings of an instrumental case study that examined the perceptions held by African-American parents on the efficacy of schools in meeting the needs of African-American learners in a North Carolina community. A theme of distrust emerged and evidenced the need for teachers, administrators, and teacher educators to reconsider approaches used with African-American parents, particularly where building culturally reciprocal home-school-community relationships is concerned. 相似文献
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Ross Gunn 《Journal of The Franklin Institute》1935,220(2):167-186
The expanding universe is described in terms of the known forces of classical physics. It is shown that great clouds of stars are non-conservative systems and that radiation reaction forces play a part in guiding stellar motions. The forces are of importance in unsymmetrical stars and evidence is collected to show that perhaps all stars are possessed of deep seated thermal asymmetries. The forces continually act to increase the mean velocity of the stars and the galaxy is calculated to expand at a rate which closely approximates the observed rate of expansion. From a relation connecting the mean velocity of the stars and their age, it is deduced from the observed motions that the age of the galaxy is about 1010 years. The deduced rate of expansion of the galaxy agrees well with the observational data and is identical in form and numerical constant with Hubble's relation connecting the velocity of recession and distances of nebulæ.Because of the relative size and spacing of the extra galactic nebulæ and the short time scale it is supposed that the nebulae were formed by fission from a parent-super nebula and this resulted in thermal asymmetries which brought the newly considered forces into action.The resulting expansion was produced by slow evolutionary radiation processes which bear no direct relation to the properties of space or atomic constants.The calculations suggest that in describing the motions of typical stars over long periods of time, radiation reaction forces are as important as the classical gravitational forces. 相似文献
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A study is made of separability conditions for the Helmholtz and Laplace equations. Attention is confined to the most useful case for physical applications; namely,
- 1.
- (a) The coordinate system is either cylindrical or it has rotational symmetry, and 相似文献