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11.
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
12.
Emerging paradigms of attack challenge enterprise cybersecurity with sophisticated custom-built tools, unpredictable patterns of exploitation, and an increasing ability to adapt to cyber defenses. As a result, organizations continue to experience incidents and suffer losses. The responsibility to respond to cybersecurity incidents lies with the incident response (IR) function. We argue that (1) organizations must develop ‘agility’ in their IR process to respond swiftly and efficiently to sophisticated and potent cyber threats, and (2) Real-time analytics (RTA) gives organizations a unique opportunity to drive their IR process in an agile manner by detecting cybersecurity incidents quickly and responding to them proactively. To better understand how organizations can use RTA to enable IR agility, we analyzed in-depth data from twenty expert interviews using a contingent resource-based view. The results informed a framework explaining how organizations enable agile characteristics (swiftness, flexibility, and innovation) in the IR process using the key features of the RTA capability (complex event processing, decision automation, and on-demand and continuous data analysis) to detect and respond to cybersecurity incidents as-they-occur which, in turn, improves their overall enterprise cybersecurity performance. 相似文献
13.
Children from families of low socioeconomic status (SES) tend to experience lower academic achievement than children from middle-SES families. This discrepancy can be attributed to a range of parental factors. The present study tested: (1) the extent to which academic achievement in three core subjects differs between children from low- and middle-SES backgrounds; (2) the differences in parental expectation, parental involvement, and child engagement across the two groups; and (3) the mediating role of parental expectation, parental involvement, and child engagement in explaining how SES influences children’s academic achievement. The sample consisted of 184 primary students with low SES and 165 primary students with middle SES from mainstream primary schools in Hong Kong. Results revealed significant differences in parental expectation, parental involvement, child engagement, as well as academic achievement in Chinese and English subjects between the low-SES and middle-SES groups. Our findings also suggest that parental expectation, parental involvement, and child engagement may be important mediators in the relationship between SES and academic achievement. 相似文献
14.
XU Changqing 《Frontiers of Education in China》2020,15(3):369
The study focuses on the research performance of Double First-Class (DFC) universities in China. A theoretical framework based on economic theory and the Analytic Hierarchy Process (AHP) method for a novel evaluation model is proposed. The model is performed on a sample of 41 participant DFC universities in China. Using data collected from these universities, it was found that there is no consistency between performance ranking, input ranking, and output ranking, with the best ranked universities far from the most efficient. These findings provide empirical evidence of DFC universities’ research performance situation and suggest strategies that the government can use to propel their sustainable development. 相似文献
15.
Yi-Hung Liao Toby Mündel Yan-Ting Yang Chen-Chan Wei Shiow-Chwen Tsai 《Journal of sports sciences》2019,37(16):1805-1815
The purpose of this study was to examine CHO ingestion on a cognitive task using a field-simulated time-trial (TT) under hypoxia in well-trained triathletes. Ten male triathletes (age: 22.1 ± 1.1 years; VO2max: 59.4 ± 1.4 ml/kg/min) participated in this double-blind/crossover/counter-balanced design study. Participants completed 3 TT trials: 1) normoxic placebo (NPLA; FiO2 = 20.9%), 2) hypoxic placebo (HPLA; FiO2 = 16.3%), and 3) hypoxic CHO (HCHO; 6% CHO provided as 2 ml/kg/15 min; FiO2 = 16.3%). During the TT, physiological responses (SpO2, HR, RPE, and blood glucose/lactate), cognitive performance, and cerebral haemodynamics were measured. Hypoxia reduced TT performance by ~3.5–4% (p < 0.05), but CHO did not affect TT performance under hypoxia. For the cognitive task, CHO slightly preserved exercise-induced cognitive reaction speed but did not affect response accuracy during hypoxic exercise. However, CHO did not preserve the decreased Hb-Diff (cerebral blood flow, CBF) and increased HHb in the prefrontal lobe (p < 0.05) during hypoxic exercise, and CHO failed to preserve hypoxia-suppressed prefrontal CBF and tissue oxygen saturation. In conclusion, the present study demonstrates that CHO is effective in sustaining reaction speed for a cognitive task but not promoting TT performance during hypoxic exercise, which would be important for strategy-/decision-making when athletes compete at moderate high-altitude. 相似文献
16.
S. Béliard J. Cassirame G. Ennequin G. Coratella N. Tordi 《Journal of sports sciences》2019,37(6):708-716
During soccer matches, performance decrements have been reported that relate to both physical abilities and technical skills. To investigate the effects of low-frequency electrical stimulation LFES (VeinoplusSport®, Ad Rem Technology, France) administered during half-time recovery on performance alterations during the second half. Twenty-two highly trained young players undertook a soccer-match simulation (SAFT90). During half-time, they were randomly assigned to LFES group or Placebo group. Each half was split into 3 bouts of 12 minutes. Following each bout, maximal strike speed (MSS), sprint test (ST), maximal sprint accelerations (MA) and metabolic power (MP) were determined in both groups. Arterial (AF) and venous flows (VF) were measured at rest and at the end of half-time. LEFS group exhibited beneficial effects on performance compared to the Placebo group with a likely effect for MSS, ST, MA, and a possible effect for MP. AF and VF increased statistically more in LEFS group compared to Placebo group. The use of specific calf-pump LFES during half-time of a youth simulated soccer match attenuated the decrease in performance during the second half compared to Placebo group. This effect is most marked at the beginning of the second half with regards to explosive parameters. 相似文献
17.
Firms are increasingly relying on business insights obtained by deploying data analytics. Analytics-driven business decisions have thus taken a strategic imperative role for the competitive advantage of a firm to endure. The extent and effectiveness through which business firms can actually derive benefits by deploying big data-based practices requires deep analysis and calls for extensive research. This study extends the big data analytics capability (BDAC) model by examining the mediatory effects of organizational culture (CL) between internal analytical knowledge (KN) and BDAC, as well as the mediating effects of BDAC between CL and firm performance. The findings bring into focus that CL plays the role of complementary mediation between BDAC and KN to positively impact firm performance (FP); BDAC also plays a similar mediatory role between CL and the performance of a firm. 相似文献
18.
Lisa Shepherd 《Support for Learning》2014,29(2):167-176
This article explores an eight‐month community theatre project with young people for whom English is a second language. Working as a creative practitioner facilitating young people to explore their personal stories of transition to the UK, the dramatherapist discovered comedy to be an important and poignant vehicle for expression of the emotional and psychological material associated with transition. In this article the author explores her experience of working with a group of young people who came together from all over the world to share their experiences of transition through the use of comedic theatre techniques. 相似文献
19.
The development of artificial intelligence (AI) technology expands the boundary of business practice, inducing the emergence and application of business intelligence (BI) that has promoted the transformation of information techniques to optimize business decision and operation. However, there is a lack of theoretical consensus and measurement of the technology embedded in BI at present. This study exploratively develops the Sense-Transform-Drive (STD) conceptual model of BI based on dynamic capabilities theory and organizational evolutionary theory to explain the core BI capabilities. By using factoring analysis and structural equation modeling analysis, we extract the latent constructs and empirically verify the validity of the STD model and further examine the correlation and mode of interaction of the three core BI capabilities and the impact of BI application on firm performance in the real economy with a sample contextual to Chinese business practices. The study results show that there are direct and high-intensity cumulative positive effects among the structural components of the STD conceptual model and BI-related dynamic capabilities can enhance operating efficiency and firm performance. 相似文献
20.
Yang Liu Binghong Gao Jiru Li Zuchang Ma Yining Sun 《Sports biomechanics / International Society of Biomechanics in Sports》2020,19(2):168-179
AbstractThe aim of this study was to investigate whether changes on foot-stretcher height were associated with characteristics of better rowing performance. Ten male rowers performed a 200 m rowing trial at their racing rate at each of three foot-stretcher heights. A single scull was equipped with an accelerometer to collect boat acceleration, an impeller with embedded magnets to collect boat speed, specially designed gate sensors to collect gate force and angle, and a compact string potentiometer to collect leg drive length. All sensor signals were sampled at 50 Hz. A one-way repeated measures ANOVA showed that raising foot-stretcher position had a significant reduction on total gate angle and leg drive length. However, a raised foot-stretcher position had a deeper negative peak of boat acceleration at the catch, a lower boat fluctuation, a faster leg drive speed, a larger gate force for the port and starboard side separately. This could be attributed to the optimisation of the magnitude and direction of the foot force with a raised foot-stretcher position. Although there was a significant negative influence of a raised foot-stretcher position on two kinematic variables, biomechanical evidence suggested that a raised foot-stretcher position could contribute to the improvement of rowing performance. 相似文献