The Impact of Video Speed on the Estimation of Time Duration in Sport

Author(s):  
Lisa-Marie Schütz ◽  
Geoffrey Schweizer ◽  
Henning Plessner

The authors investigated the impact of video speed on judging the duration of sport performance. In three experiments, they investigated whether the speed of video presentation (slow motion vs. real time) has an influence on the accuracy of time estimation of sporting activities (n1 = 103; n2 = 100; n3 = 106). In all three studies, the time estimation was more accurate in real time than in slow motion, in which time was overestimated. In two studies, the authors initially investigated whether actions in slow motion are perceived to last longer because the distance they cycled or ran is perceived to be longer (n4 = 92; n5 = 106). The results support the hypothesis that the duration of sporting activities is estimated more accurately when they are presented in real time than in slow motion. Sporting officials’ judgments that require accurate time estimation may thus be biased when based on slow-motion displays.

2019 ◽  
Vol 150 ◽  
pp. 1-10 ◽  
Author(s):  
Shuang Wen ◽  
Hong Qi ◽  
Xiao-Ying Yu ◽  
Ya-Tao Ren ◽  
Lin-Yang Wei ◽  
...  

2019 ◽  
Vol 147 ◽  
Author(s):  
Jessica Y. Wong ◽  
Edward Goldstein ◽  
Vicky J. Fang ◽  
Benjamin J. Cowling ◽  
Peng Wu

Abstract Statistical models are commonly employed in the estimation of influenza-associated excess mortality that, due to various reasons, is often underestimated by laboratory-confirmed influenza deaths reported by healthcare facilities. However, methodology for timely and reliable estimation of that impact remains limited because of the delay in mortality data reporting. We explored real-time estimation of influenza-associated excess mortality by types/subtypes in each year between 2012 and 2018 in Hong Kong using linear regression models fitted to historical mortality and influenza surveillance data. We could predict that during the winter of 2017/2018, there were ~634 (95% confidence interval (CI): (190, 1033)) influenza-associated excess all-cause deaths in Hong Kong in population ⩾18 years, compared to 259 reported laboratory-confirmed deaths. We estimated that influenza was associated with substantial excess deaths in older adults, suggesting the implementation of control measures, such as administration of antivirals and vaccination, in that age group. The approach that we developed appears to provide robust real-time estimates of the impact of influenza circulation and complement surveillance data on laboratory-confirmed deaths. These results improve our understanding of the impact of influenza epidemics and provide a practical approach for a timely estimation of the mortality burden of influenza circulation during an ongoing epidemic.


Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3239
Author(s):  
Wael S. Hassanein ◽  
Marwa M. Ahmed ◽  
Mohamed I. Mosaad ◽  
A. Abu-Siada

Real-time estimation of transmission line (TL) parameters is essential for proper management of transmission and distribution networks. These parameters can be used to detect incipient faults within the line and hence avoid any potential consequences. While some attempts can be found in the literature to estimate TL parameters, the presented techniques are either complex or impractical. Moreover, none of the presented techniques published in the literature so far can be implemented in real time. This paper presents a cost-effective technique to estimate TL parameters in real time. The proposed technique employs easily accessible voltage and current data measured at both ends of the line. For simplicity, only one quarter of the measured data is sampled and utilized in a developed objective function that is solved using the whale optimization algorithm (WOA) to estimate the TL parameters. The proposed objective function comprises the sum of square errors of the measured data and the corresponding estimated values. The robustness of the proposed technique is tested on a simple two-bus and the IEEE 14-bus systems. The impact of uncertainties in the measured data including magnitude, phase, and communication delay on the performance of the proposed estimation technique is also investigated. Results reveal the effectiveness of the proposed method that can be implemented in real time to detect any incipient variations in the TL parameters due to abnormal or fault events.


AIAA Journal ◽  
2013 ◽  
Vol 51 (1) ◽  
pp. 178-185 ◽  
Author(s):  
Hao Jiang ◽  
Bartel van der Veek ◽  
Daniel Kirk ◽  
Hector Gutierrez

2018 ◽  
Vol 11 (2) ◽  
Author(s):  
David Hammerschmidt ◽  
Clemens Wöllner

This study investigated the effects of music and playback speed on arousal and visual perception in slow-motion scenes taken from commercial films. Slow-motion scenes are a ubiquitous film technique and highly popular. Yet the psychological effects of mediated time-stretching compared to real-time motion have not been empirically investigated. We hypothesised that music affects arousal and attentional processes. Furthermore, we assumed that playback speed influences viewers’ visual perception, resulting in a higher number of eye movements and larger gaze dispersion. Thirty-nine participants watched three film excerpts in a repeated-measures design in conditions with or without music and in slow motion vs. adapted real-time motion (both visual-only). Results show that music in slow-motion film scenes leads to higher arousal compared to no music as indicated by larger pupil diameters in the former. There was no systematic effect of music on visual perception in terms of eye movements. Playback speed influenced visual perception in eye movement parameters such that slow motion resulted in more and shorter fixations as well as more saccades compared to adapted real-time motion. Furthermore, in slow motion there was a higher gaze dispersion and a smaller centre bias, indicating that individuals attended to more detail in slow motion scenes.


2021 ◽  
Author(s):  
Masaya Misaki ◽  
Jerzy Bodurka

AbstractObjectiveComprehensive denoising is imperative in fMRI analysis to reliably evaluate neural activity from the blood oxygenation level dependent signal. In real-time fMRI, however, only a minimal denoising process has been applied and the impact of insufficient denoising on online brain activity estimation has not been assessed comprehensively. This study evaluated the noise reduction performance of online fMRI processes in a real-time estimation of regional brain activity and functional connectivity.ApproachWe performed a series of real-time processing simulations of online fMRI processing, including slice-timing correction, motion correction, spatial smoothing, signal scaling, and noise regression with high-pass filtering, motion parameters, motion derivatives, global signal, white matter/ventricle average signals, and physiological noise models with image-based retrospective correction of physiological motion effects (RETROICOR) and respiration volume per time (RVT).Main resultsAll the processing was completed in less than 400 ms for whole-brain voxels. Most processing had a benefit for noise reduction except for RVT that did not work due to the limitation of the online peak detection. The global signal regression, white matter/ventricle signal regression, and RETORICOR had a distinctive noise reduction effect, depending on the target signal, and could not substitute for each other. Global signal regression could eliminate the noise-associated bias in the mean dynamic functional connectivity across time.SignificanceThe results indicate that extensive real-time denoising is possible and highly recommended for real-time fMRI applications.


2021 ◽  
Author(s):  
Gemma Postill ◽  
Regan Murray ◽  
Andrew S Wilton ◽  
Richard A Wells ◽  
Renee Sirbu ◽  
...  

BACKGROUND Early estimates of excess mortality are crucial for understanding the impact of COVID-19. However, there is a lag of several months in the reporting of vital statistics mortality data for many jurisdictions. In Ontario, a Canadian province, certification by a coroner is required before cremation can occur, creating timely mortality data that encompasses the majority of deaths within the province. OBJECTIVE Our objectives were to (1) validate the ability of cremation data in permitting real-time estimation of excess all-cause mortality, interim of vital statistics data, and (2) describe the patterns of excess mortality. METHODS Cremation records from January 2020 until April 2021 were compared to the historical records from 2017-2019, grouped according to week, age, sex, and COVID-19 status. Cremation data were compared to Ontario’s provisional vital statistics mortality data released by Statistics Canada. The 2020 and 2021 records were then compared to previous years to determine whether there was excess mortality and if so, which age groups had the greatest number of excess deaths during the COVID Pandemic, and whether deaths attributed to COVID-19 account for the entirety of the excess mortality. RESULTS Between 2017-2019, cremations were performed for 67.4% (95% CI: 67.3–67.5%) of deaths; the proportion of cremated deaths remained stable throughout 2020, establishing that the COVID-19 pandemic did not significantly alter cremation practices, even within age and sex categories. During the first wave (from April to June 2020), cremation records detected a 16.9% increase (95% CI: 14.6–19.3%) in mortality. The accuracy of this excess mortality estimation was later confirmed by vital statistics data. CONCLUSIONS The stability in the percent of Ontarians cremated and the completion of cremation data several months before vital statistics data, enables accurate estimation of all-causes mortality in near real-time with cremation data. These findings demonstrate the utility of cremation data to provide timely mortality information during public health emergencies.


2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Lizhen Gao ◽  
Yingying Zhang ◽  
Xiaoming Zhang ◽  
Yuyang Xue

In the course of the guidance transformation of the rotating projectile, the accurate acquisition of the roll angle and roll angle rate is very important to the attitude determination and guidance control of the rotating projectile. However, due to the impact of high rotation and high overload of projectile, MEMS gyros have problems such as limited range, saturation, overload, and even performance degradation, which make the roll angle rate unable to be output normally. At the same time, because the MEMS gyro estimation of roll angle is in the form of angular rate integral, the roll angle cannot be estimated normally if the roll angle rate cannot be accurately obtained. In order to solve this problem, a real-time estimation of projectile roll angle and roll rate based on geomagnetic information under high dynamic and high overload conditions is presented. Firstly, according to the motion characteristics of the rotating projectile, the motion model of the projectile is established, and the roll angle and roll angle rate of the projectile are estimated by Kalman filtering algorithm under the conditions of high axial rotation and high overload. Considering the high dynamic characteristics of the rotating projectile, based on the Kalman filter, the algorithm of the forgetting filter with the forgetting factor is further adopted to estimate the roll angle and roll angle rate, so as to reduce the error caused by the estimation delay in the process of high-speed dynamic change. Simulation data and semiphysical test results show that the accuracy of roll angle estimated by this method reaches about 2° in semiphysical test, which is one time higher than that calculated by the system. In the semiphysical experiment, the accuracy of the estimated roll rotation rate reaches 5 °/s, which is more than 6 times higher than that obtained by direct derivation. In the high dynamic stage, compared with the pure Kalman filter, the accuracy of roll angle with forgetting factor estimation is improved by an order of magnitude, and the accuracy of roll angle rate is improved by 4 times, which meets the desired accuracy of rotating projectile.


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