In this work, a general method to manipulate the angle of reflection from an arbitrary two-dimensional (2D) surface is proposed by applying an appropriate phase discontinuity along the arbitrary surface. Three surfaces, including plane surface, parabolic surface and circular surface are taken as instances to validate this method. The results show that angle of reflection is conducted to [Formula: see text] for a wave incident to a plane surface at [Formula: see text], while [Formula: see text] for a wave incident to the parabolic and circular surfaces normally. This kind of manipulation of acoustic waves for arbitrary reflecting surfaces opens up an avenue for reflected wavefront modulations and associated applications such as anti-sonar technology.
In order to speed up and enhance the robustness of speech recognition system, this paper proposes a speech recognition algorithm based on segment-level features of GFCC. In training and testing stage we use segment-level features of GFCC which is more robust to noise instead of the widely used MFCC features. Experiment results show that both the training time and test time decreased, while the accuracy of system was made to improve.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.