44,023 research outputs found
Primordial power spectrum of tensor perturbations in Finsler spacetime
We first investigate the gravitational wave in the flat Finsler spacetime. In
the Finslerian universe, we derive the perturbed gravitational field equation
with tensor perturbations. The Finslerian background spacetime breaks
rotational symmetry and induces parity violation. Then we obtain the modified
primordial power spectrum of tensor perturbations. The parity violation feature
requires that the anisotropic effect contributes to angular
correlation coefficients with and with . The numerical
results show that the anisotropic contributions to angular correlation
coefficients depend on , and and angular correlation coefficients
are different.Comment: 15 pages, 12 fugures. arXiv admin note: text overlap with
arXiv:1502.0225
Pushing towards the Limit of Sampling Rate: Adaptive Chasing Sampling
Measurement samples are often taken in various monitoring applications. To
reduce the sensing cost, it is desirable to achieve better sensing quality
while using fewer samples. Compressive Sensing (CS) technique finds its role
when the signal to be sampled meets certain sparsity requirements. In this
paper we investigate the possibility and basic techniques that could further
reduce the number of samples involved in conventional CS theory by exploiting
learning-based non-uniform adaptive sampling.
Based on a typical signal sensing application, we illustrate and evaluate the
performance of two of our algorithms, Individual Chasing and Centroid Chasing,
for signals of different distribution features. Our proposed learning-based
adaptive sampling schemes complement existing efforts in CS fields and do not
depend on any specific signal reconstruction technique. Compared to
conventional sparse sampling methods, the simulation results demonstrate that
our algorithms allow less number of samples for accurate signal
reconstruction and achieve up to smaller signal reconstruction error
under the same noise condition.Comment: 9 pages, IEEE MASS 201
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