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Evaluating Performance of Speech Enhancement Algorithms
Published in Philipos C. Loizou, Speech Enhancement, 2013
The requirement that the lists had an equal range of difficulty is an important one and was placed to avoid having systems always perform near zero or near 100% correct. If, for instance, the word test is too easy, then all systems will perform nearly one-hundred-percent correct and will therefore learn nothing from the test as to which system is better. This effect is referred to in the literature as the ceiling effect, since the system performs near the ceiling, that is, maximum performance. Similarly, if the word test is too difficult, consisting of say a large number of unfamiliar words, then all systems will perform near zero percent correct. This is referred to in the literature as the floor effect, since the system performs near the floor, that is, minimum performance. For these reasons, in order to avoid any floor or ceiling effects, Egan [8] designed the lists to be of equal range of difficulty.
Data Sources and Research Tools for Human Factors
Published in Steven J. Landry, Handbook of Human Factors in Air Transportation Systems, 2017
Mark Wiggins, Shayne Loft, Johanna Westbrook
A third measure of central tendency, although rarely used, is the mode. The mode is the most frequently occurring value in a dataset and is actually useful in establishing whether a ceiling or floor effect was evident. A ceiling effect occurs when a significant proportion of the values are recorded at a maximal value. For example, in an examination, the majority of students might achieve 100%. Conversely, a floor effect occurs where a significant proportion of data points are recorded at a minimal value. In either case, it reflects a systematic issue either in the way that the data were collected or within the examination itself.
Aerodynamic analysis on unsteady characteristics of a ducted fan hovering in ceiling effect
Published in Engineering Applications of Computational Fluid Mechanics, 2023
Yiwei Luo, Tianfu Ai, Yuhang He, Zhiran Zhao, Bin Xu, Yuping Qian, Jie Peng, Yangjun Zhang
Previous studies have shown that, the aerodynamic performance of ducted fans is more sensitive to wall constraints compared with that of propellers. Taking the ground effect as an example, the ground effect has a significant impact on the propeller in the range of 0 to 2R, while the range changes to 0 to 4R for the ducted fan (Han et al., 2021; Matus-Vargas et al., 2021; Mi, 2020). The influence of ceiling effect on thrust characteristics of the ducted fan is illustrated in Figure 9, where denotes the thrust in ceiling effect and denotes the thrust out of ceiling effect. Experimental data of cases with z/R = 0.4, 0.5, 1, and 2 well supports the simulation results. The figure reveals two major features of the ducted fan performance. Time-averaged thrust characteristics
A comparison of the relationship between individual values and aggressive driving in five countries
Published in Journal of Transportation Safety & Security, 2022
Gizem Fındık, Bilgesu Kaçan, Gaye Solmazer, Özlem Ersan, Yeşim Üzümcüoğlu Zihni, Derya Azık, Türker Özkan, Timo Lajunen, Bahar Öz, Anton Pashkevich, Maria Pashkevich, Vassiliki Danelli-Mylona, Dimitra Georgogianni, Ema Berisha Krasniqi, Muhamed Krasniqi, Evangelos Makris, Ksenia Shubenkova, Gentianë Xheladini
The results showed that individual values explained aggressive driving behaviours of self, but not those of others. This indicates that perceived frequency of aggressive driving behaviours of others do not reflect the values adopted by the individuals themselves. This finding may be explained with the ceiling effect. To be specific, when the mean aggressive driving scores were examined, it is found that “other” mean scores of both AW and HAR were higher than “self” mean scores in all five samples (see Figure 2). These differences were significant for four samples, but not for the Russian sample. On the other hand, the reason for this ceiling effect may come from self-related biases. Previous studies show that drivers display various self-related biases: actor-observer effect (Stewart, 2005), self-enhancement bias (Fındık, Uslu, Öz, Lajunen, & Özkan, 2016), optimism bias (DeJoy, 1989), and so on. It is possible that the participants in our sample employed one or more of these biases and cognitive shortcuts (Hoorens, 1993) in explaining others’ aggressive driving, resulting in a lack of relationship. It was noteworthy, however, that the lack of significant relationship between values and aggressive driving of others was country-independent.
Stable impact and contact force control by UAV for inspection of floor slab of bridge
Published in Advanced Robotics, 2018
Takahiro Ikeda, Shogo Yasui, Satoshi Minamiyama, Kenichi Ohara, Satoshi Ashizawa, Akihiko Ichikawa, Akihisa Okino, Takeo Oomichi, Toshio Fukuda
In Exp. 1, the altitude of the UAV followed the desired altitudes from 2.0 [m] to 3.5 [m]. When the desired altitude was less than 1.5 [m], the altitude of the UAV overshot the desired altitude. This was because the ground effect increased the thrust force of the UAV. The ground effect means that the ground reflects the air flow generated by the propellers of the UAV [27–29]. The amount of the ground effect increases relative to the size of the propeller and the distance between the ground and the UAV. Even though compensation of the ground effect was implemented into the altitude control, the compensation was not enough for the ground effect. Therefore, the compensation must be improved in our future work. When the desired altitude was more than 4.0 [m], the altitude of the UAV overshot the desired altitude. The reason was assumed to be the presence of a ceiling effect similar to the ground effect. This ceiling effect means that the air pressure above the UAV was decreased by the air flow of the propellers and the UAV was attracted to the ceiling (floor slab) due to the decrease [29,30]. The height of the floor slab was about 5.0 [m] and the effect occurred when the distance between the floor slab and the UAV was less than 1.0 [m]. The ceiling effect will be verified in our future work. After about 110 [sec], the thrust force decreased due to the voltage drop of the battery. The battery drop compensation will also be improved.