Bats use frequency-modulated echolocation to identify and capture moving objects in real three-dimensional space. Experimental evidence indicates that bats are capable of locating static objects with a range accuracy of less than 1 μs. A previously introduced model estimates ranges of multiple, static objects using linear frequency modulation (LFM) sound and Gaussian chirplets with a carrier frequency compatible with bat emission sweep rates. The delay time for a single object was estimated with an accuracy of about 1.3 μs by measuring the echo at a low signal-to-noise ratio (SNR). The range accuracy was dependent not only on the SNR but also the Doppler shift, which was dependent on the movements. However, it was unclear whether this model could estimate the moving object range at each timepoint. In this study, echoes were measured from the rotating pole at two receiving points by intermittently emitting LFM sounds. The model was shown to localize moving objects in two-dimensional space by accurately estimating the object's range at each timepoint.
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http://dx.doi.org/10.1121/1.4773254 | DOI Listing |
J Cogn
January 2025
Department of Communication and Cognition, Tilburg School of Humanities and Digital Sciences, Tilburg University, The Netherlands.
Despite pictures being static representations, they use various cues to suggest dynamic motion. To investigate the effectiveness of different motion cues in conveying speed in static images, we conducted 3 experiments. In Experiment 1, we compared subjective speed ratings given for motion lines trailing behind movers, suppletion lines replacing parts of the movers and backfixing lines set in the background against the baseline of having no extra cue.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Applied Mathematics Laboratory, Courant Institute of Mathematical Sciences, Department of Mathematics, New York University, New York, NY 10012.
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View Article and Find Full Text PDFJ Exp Psychol Hum Percept Perform
January 2025
Faculty of Arts and Science, Kyushu University.
Personal objects are known to have several psychological effects on their owners. However, the formation of a sense of object ownership (SoOO) remains unclear. This study tested the hypothesis that a sense of agency (SoA) is related to the formation of SoOO.
View Article and Find Full Text PDFSci Rep
January 2025
College of Mechanical and Electrical Engineering, Zhoukou Normal University, Zhoukou, 466000, China.
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View Article and Find Full Text PDFACS Appl Mater Interfaces
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Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States.
Thermal energy harvesting for high-speed moving objects is particularly promising in providing an efficient and sustainable energy source to enhance operational capabilities and endurance. Thermoelectric (TE) technology, by exploiting temperature gradients between a heat source and ambient temperature, can provide a continuous power supply to such systems, reducing the reliance on conventional batteries and extending operation times. However, the integrated thermoelectric generator (TEG) system design research is far behind materials development.
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