Reliability of judging in DanceSport

Purpose The aim of this study was to assess the reliability and validity of the new judging system in DanceSport. Methods Eighteen judges rated the 12 best placed adult dancing couples competing at an international competition. They marked each couple on all judging criteria on a 10 level scale. Absolute agreement and consistency of judging were calculated for all main judging criteria and sub-criteria. Results A mean correlation of overall judging marks was 0.48. Kendall’s coefficient of concordance for overall marks (W = 0.58) suggesting relatively low agreement among judges. Slightly lower coefficients were found for the artistic part [Partnering skills (W = 0.45) and Choreography and performance (W = 0.49)] compared to the technical part [Technical qualities (W = 0.56) and Movement to music (W = 0.54)]. ICC for overall criteria was low for absolute agreement [ICC(2,3) = 0.62] but higher for consistency [ICC(3,3) = 0.80]. Conclusion The relatively large differences between judges’ marks suggest that judges either disagreed to some extent on the quality of the dancing or used the judging scale in different ways. The biggest concern was standard error of measurement (SEM) which was often larger than the difference between dancers scores suggesting that this judging system lacks validity. This was the first research to assess judging in DanceSport and offers suggestions to potentially improve both its objectivity and validity in the future

Complete Coherent Control of a Quantum Dot Strongly Coupled to a Nanocavity

Strongly coupled quantum dot-cavity systems provide a non-linear configuration of hybridized light-matter states with promising quantum-optical applications. Here, we investigate the coherent interaction between strong laser pulses and quantum dot-cavity polaritons. Resonant excitation of polaritonic states and their interaction with phonons allow us to observe coherent Rabi oscillations and Ramsey fringes. Furthermore, we demonstrate complete coherent control of a quantum dot-photonic crystal cavity based quantum-bit. By controlling the excitation power and phase in a two-pulse excitation scheme we achieve access to the full Bloch sphere. Quantum-optical simulations are in good agreement with our experiments and provide insight into the decoherence mechanisms

Influence of Microclimate in a Barn on Dairy Cows’ Welfare and Production

Microclimate in a barn has a major influence on cows’ health and welfare, as well as on milk production of dairy cows. Extreme values of air temperature and humidity can negatively influence barn conditions, having thus negative effect on cows kept in barns. The research aimed to investigate influence of basic microclimate parameters on a modern dairy farm located in Eastern Croatia. Research period referred to summer season, from 01 June – 31 August 2013. Measurements were carried out in three time intervals (00:00-08:00; 08:00-16:00; 16:00-00:00) for the following parameters: temperature (T), humidity (H) and temperature-humidity index (THI). The results showed that the values of T and THI were higher than optimal values recommended by the scientific literature. Differences between the daily interval for T, H and THI were statistically highly significant (p<0.0001). Furthermore, significant difference (p<0.0001; p<0.05) was determined for all investigated parameters between June and July, and June and August. However, between July and August there was no significant difference. Although measurements were performed on a modern dairy farm equipped with additional cooling by fans, it was not sufficient to create an optimal microclimate environment for dairy cows. Because of that, additional measures need to be undertaken during summer months (for example, installation of water sprinklers) to reduce the air temperature and temperature-humidity index, all with the purpose to increase comfort of dairy cows and to prevent decrease in milk production

Evaluating goal threat in football using player and ball locations

Goal scoring in football is relatively low but vitally important, hence research has considered how goals are created and scored with measures such as expected goals prevalent. The dynamical systems theoretical perspective, considers a collective system, such as football, as existing in two states, stable (no substantive advantage for either team) or unstable (advantage present). Hence, goal scoring events occur when the system has become unstable, with a “perturbation” the event causing the system state change. Here, a “goal threat” value was calculated every second (scaled from 0 to 100) using the XY coordinates of players and the ball, weighted in relation to proximity to the goal (a potential proxy for the degree of system instability). Video recordings and synchronised Amisco 2D representations of goals (n=64) scored in Swansea City AFC English Premier League 2012/2013 matches (n=20) were analysed using Dartfish v10 Pro software. Each goal was analysed from when the play was judged to be stable (no obvious goal scoring opportunity), or the start of possession, until the goal had been scored. Goals were not always preceded by high goal threat values (maximum goal threat values ranged from 13.4 to 99.0). The authors independently subjectively determined that perturbations occurred up to 7 seconds from when the goal threat value increased by at least 40%. Thus, perturbations were not directly related to goal scoring opportunities. This novel method provides a useful, quantifiable, and simple measure of goal threat that may also aid audience engagement and measure defensive effectiveness

Pulsating hydrogen-deficient white dwarfs and pre-white dwarfs observed with TESS -- IV. Discovery of two new GW Vir stars: TIC0403800675 and TIC1989122424

We present two new GW Vir-type pulsating white dwarf stars, TIC\,0403800675 (WD\,J115727.68-280349.64) and TIC\,1989122424 (WD J211738.38-552801.18) discovered in the Transiting Exoplanet Survey Satellite (TESS) photometric data. For both stars, the TESS light curves reveal the presence of oscillations with periods in a narrow range between 400 and 410\,s, which are associated with typical gravity ($g$)-modes. Follow-up ground-based spectroscopy shows that both stars have similar effective temperature ($T_\mathrm{eff} = 110,000 \pm 10,000$\,K) and surface gravity ($\log g = 7.5 \pm 0.5$), but different He/C composition (mass fractions): He\,=\,0.75 and C\,=\,0.25 for TIC\,0403800675, and He\,=\,0.50 and C\,=\,0.50 for TIC\,1989122424. By performing a fit to their spectral energy distributions, we found for both stars radii and luminosities of $R=0.019\pm0.002\,R_\odot$ and $\log(L/L_\odot)=1.68^{+0.15}_{-0.24}$, respectively. By employing evolutionary tracks of PG~1159 stars, we find the masses of both stars to be $0.56\pm0.18 M_{\odot}$ from the $\log g$-$T_\mathrm{eff}$ diagram and $0.60^{+0.11}_{-0.09} M_{\odot}$ from the Hertzsprung Russell diagram.Comment: 8 Pages. arXiv admin note: text overlap with arXiv:2108.1109