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K. S. Yakovlev D. A. Makarov E. S. Baskin 《Scientific and Technical Information Processing》2015,42(5):347-358
In the article we solve path planning task for an agent being multirotor unmanned aerial vehicle (multicopter). We propose an approach of estimating path geometry constraints based on UAV flight dynamics model and control constraints. Than we introduce a new path finding method which takes into consideration those geometry constraints and study this method both theoretically and empirically. 相似文献
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Avi I. Mintz 《Journal of Philosophy of Education》2011,45(4):657-673
Scholars who have taken interest in Theaetetus' educational theme argue that Plato contrasts an inferior, even dangerous, sophistic education to a superior, philosophical, Socratic education. I explore the contrasting exhortations, methods, ideals and epistemological foundations of Socratic and Protagorean education and suggest that Socrates' treatment of Protagoras as educator is far less dismissive than others claim. Indeed, Plato, in Theaetetus, offers a qualified defence of both Socrates and Protagoras. Socrates and Protagoras each dwell in the middle ground between the extremes presented in the dialogue's digression, which contrasts the life of the philosopher and the life of the courtroom orator. Both Socrates and Protagoras demonstrate a serious engagement with both politics and philosophy. Theodorus presents an educational option in which theory is divorced from politics while an ignoble sophistic education is presented as political but divorced from theory. Protagorean education, in Theaetetus, emerges as superior to a base sophistic education, though it remains inferior to Socratic education. 相似文献
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Leonardo S. Fortes Dalton De Lima-Junior Lenamar Fiorese José R. A. Nascimento-Júnior Arnaldo L. Mortatti Maria E. C. Ferreira 《Journal of sports sciences》2020,38(5):552-558
ABSTRACTThe objective of this study was to analyse the effect of the use of social networks in smartphones or playing video games on the passing decision-making performance in professional soccer athletes. Participants were 25 male professional soccer athletes (mean ± SD: age 23.4 ± 2.8 years). The participants performed three randomised conditions divided into three groups: control (CON), smartphone (SMA), and video game (VID). Before and after each experimental condition, the Stroop Task assessed the level of induced mental fatigue. Then, the athletes performed a simulated soccer match. A CANON® camera recorded the matches for further analysis on passing decision-making performance. A group effect was identified (p < .01) with impairment on passing decision-making performance for the SMA (p = .01, ES = 0.5) and VID (p = .01, ES = 0.5) conditions. We concluded that the use of social networks on smartphones and/or playing video games right before official soccer matches might impair the passing decision-making performance in professional soccer athletes. 相似文献
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ABSTRACTRecently, there has been much controversy over the International Association of Athletics Federation (IAAF) regulations regarding eligibility to compete and natural testosterone levels in female athletes. Much interest lies in the analysis of Caster Semenya's extraordinary performance. The objective of this work were, a) Complete an analysis of Caster Semenya's results during the 800m finals and b) search for existing similar performances by other female athletes. We analysed the results of the finals of all IAAF World Championships and Olympic Games from 1984–2016, including the 800m results of the Diamond Leagues 2016–2018. Exponential curves were fit to the data to characterise and predict performance for each event. Caster Semenya's finishing times before her ineligibility to compete and after the suspension of the IAAF hyperandrogenism regulation were found to be 1.24% and 1.49%, respectively, faster than the characteristic performance of the elite-standard in the women’s 800m final. Other female athletes, with finishing times faster than the ones predicted by the characteristic curves were also discovered. The percentage difference in performance between Caster Semenya and the other participants did not reach 3% in the 800m event. No conclusions can be drawn regarding extraordinary results ever performed during the 100m, 200m or 400m finals. 相似文献