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362.
This paper is concerned with detecting the presence of switching behavior in experimentally obtained posturographic data sets by means of a novel algorithm that is based on a combination of wavelet analysis and Hilbert transform. As a test-bed for the algorithm, we first use a switched model of human balance control during quiet standing with known switching behavior in four distinct configurations. We obtain a time–frequency representation of a signal generated by our model system. We are then able to detect manifestations of discontinuities (switchings) in the signal as spiking behavior. The frequency of switchings, measured by means of our algorithm and detected in our models systems, agrees with the frequency of spiking behavior found in the experimentally obtained posturographic data. 相似文献
363.
Michael Schredl Arthur T. Funkhouser Claude M. Cornu Hans-Peter Hirsbrunner Marcel Bahro 《Consciousness and cognition》2001,10(4):496-502
The coefficients of internal consistency and retest reliability had been rarely investigated within the methodology of dream content analysis. Analyzing a dream series of elderly, healthy persons obtained from weekly telephone interviews, the internal consistency of a series of 20 dreams and retests after 4 or 22 weeks, respectively, had been computed. The findings indicate that dream recall and dream length are quite stable, but dream characteristics such as bizarreness and emotional tone underlie large intraindividual fluctuations. In order to obtain reliable measures for these variables which will be important for correlational studies, including waking-life trait measures, one has to obtain as many dreams as possible (about 20) in a very short time period. Further research is needed to extend the present findings to diary dreams and laboratory dreams. 相似文献
364.
Outstanding advantages of OFDM helps high data rate communication systems such as Digital Video Broadcasting (DVB) and mobile worldwide interoperability for microwave access (mobile Wi-MAX). But, OFDM system grieves from grave issue of high PAPR. In OFDM system data output is superposition of multiple sub-carriers and leads to big data. In this case some instantaneous power output might increase greatly and become far higher than the mean power of system. In order to make Neutrosophic data for less PAPR criteria, Gaussian filter based Costas coding is proposed. This paper also proposes feeding the Orthogonal Frequency Division Multiplexed signal (OFDM) into a phase accumulator to obtain frequency modulation, with the aim of reducing the peak to average power ratio (PAPR). For associated radar with modulated waveform mentioned here can be used to enhance the performance. It is widely used to analyze the variation of the output waveform further, the implementation results using MATLAB show that the ratio of average power to peak power is reducing considerably in comparing with the conventional method. Consequently; the signal can assume to fade in a frequency selective channel without an equalizer. 相似文献
365.
ABSTRACTPrevious studies reported a memory facilitation effect in which increased attention to one task facilitates the memory performance on another. Here we examined the characteristics of this “attentional boost effect” (ABE), and demonstrated how attention level during memory encoding influences the ABE strength by changing the occurring frequency of the attention-engaging target signal relative to the non-attention-engaging distractor signal (Experiment 1), and the physical salience of colour of the target signal (Experiment 2). The results indicated stronger ABE in conditions with a low ratio of target signal trials and with a salient target signal. Experiment 3 examined the role of spatial attention, which sought to measure how the distance between the target signal and the to-be-encoded item would influence the ABE strength. The results showed that the ABE strength was not influenced by the distance between the two. Overall, these findings suggest ABE may be mainly based on temporal attention. 相似文献
366.
Valentina Cartei Wind Cowles Robin Banerjee David Reby 《The British journal of developmental psychology》2014,32(1):100-106
Adult listeners are capable of identifying the gender of speakers as young as 4 years old from their voice. In the absence of a clear anatomical dimorphism in the dimensions of pre‐pubertal boys' and girls' vocal apparatus, the observed gender differences may reflect children's regulation of their vocal behaviour. A detailed acoustic analysis was conducted of the utterances of 34 6‐ to 9‐year‐old children, in their normal voices and also when asked explicitly to speak like a boy or a girl. Results showed statistically significant shifts in fundamental and formant frequency values towards those expected from the sex dimorphism in adult voices. Directions for future research on the role of vocal behaviours in pre‐pubertal children's expression of gender are considered. 相似文献