10,858 research outputs found
Deep Room Recognition Using Inaudible Echos
Recent years have seen the increasing need of location awareness by mobile
applications. This paper presents a room-level indoor localization approach
based on the measured room's echos in response to a two-millisecond single-tone
inaudible chirp emitted by a smartphone's loudspeaker. Different from other
acoustics-based room recognition systems that record full-spectrum audio for up
to ten seconds, our approach records audio in a narrow inaudible band for 0.1
seconds only to preserve the user's privacy. However, the short-time and
narrowband audio signal carries limited information about the room's
characteristics, presenting challenges to accurate room recognition. This paper
applies deep learning to effectively capture the subtle fingerprints in the
rooms' acoustic responses. Our extensive experiments show that a two-layer
convolutional neural network fed with the spectrogram of the inaudible echos
achieve the best performance, compared with alternative designs using other raw
data formats and deep models. Based on this result, we design a RoomRecognize
cloud service and its mobile client library that enable the mobile application
developers to readily implement the room recognition functionality without
resorting to any existing infrastructures and add-on hardware.
Extensive evaluation shows that RoomRecognize achieves 99.7%, 97.7%, 99%, and
89% accuracy in differentiating 22 and 50 residential/office rooms, 19 spots in
a quiet museum, and 15 spots in a crowded museum, respectively. Compared with
the state-of-the-art approaches based on support vector machine, RoomRecognize
significantly improves the Pareto frontier of recognition accuracy versus
robustness against interfering sounds (e.g., ambient music).Comment: 29 page
Towards Quantifying Complexity with Quantum Mechanics
While we have intuitive notions of structure and complexity, the
formalization of this intuition is non-trivial. The statistical complexity is a
popular candidate. It is based on the idea that the complexity of a process can
be quantified by the complexity of its simplest mathematical model - the model
that requires the least past information for optimal future prediction. Here we
review how such models, known as -machines can be further simplified
through quantum logic, and explore the resulting consequences for understanding
complexity. In particular, we propose a new measure of complexity based on
quantum -machines. We apply this to a simple system undergoing
constant thermalization. The resulting quantum measure of complexity aligns
more closely with our intuition of how complexity should behave.Comment: 10 pages, 6 figure, Published in the Focus Point on Quantum
information and complexity edition of EPJ Plu
Advertising Effectiveness of Different Social Appeals through Microblog
In today’s interactive marketplace,microblog has become a powerful social marketing and advertising platform. An important type of information in microblog is consumer generated and forwarded advertising. In our study, we explore advertising effects of different social appeals through microblog. We find that oriented appeals (i.e., other-oriented and self-oriented appeals) are more effective than non-oriented appeals. But the difference between other-oriented appeal and self-oriented appeal is insignificant. The relationship between sender and receiver moderate the result. Other-oriented appeal is more effective than self-oriented appeal for dyads with offline relationship, while self-oriented appeal is more effective for dyads of online-only relationship
Overarching framework between Gaussian quantum discord and Gaussian quantum illumination
We cast the problem of illuminating an object in a noisy environment into a
communication protocol. A probe is sent into the environment, and the presence
or absence of the object constitutes a signal encoded on the probe. The probe
is then measured to decode the signal. We calculate the Holevo information and
bounds to the accessible information between the encoded and received signal
with two different Gaussian probes---an Einstein-Podolsky-Rosen (EPR) state and
a coherent state. We also evaluate the Gaussian discord consumed during the
encoding process with the EPR probe. We find that the Holevo quantum advantage,
defined as the difference between the Holevo information obtained from the EPR
and coherent state probes, is approximately equal to the discord consumed.
These quantities become exact in the typical illumination regime of low object
reflectivity and low probe energy. Hence we show that discord is the resource
responsible for the quantum advantage in Gaussian quantum illumination.Comment: 12 pages, 8 figure
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