11,746 research outputs found
Self-Supervised Audio-Visual Co-Segmentation
Segmenting objects in images and separating sound sources in audio are
challenging tasks, in part because traditional approaches require large amounts
of labeled data. In this paper we develop a neural network model for visual
object segmentation and sound source separation that learns from natural videos
through self-supervision. The model is an extension of recently proposed work
that maps image pixels to sounds. Here, we introduce a learning approach to
disentangle concepts in the neural networks, and assign semantic categories to
network feature channels to enable independent image segmentation and sound
source separation after audio-visual training on videos. Our evaluations show
that the disentangled model outperforms several baselines in semantic
segmentation and sound source separation.Comment: Accepted to ICASSP 201
Content Placement in Cache-Enabled Sub-6 GHz and Millimeter-Wave Multi-antenna Dense Small Cell Networks
This paper studies the performance of cache-enabled dense small cell networks
consisting of multi-antenna sub-6 GHz and millimeter-wave base stations.
Different from the existing works which only consider a single antenna at each
base station, the optimal content placement is unknown when the base stations
have multiple antennas. We first derive the successful content delivery
probability by accounting for the key channel features at sub-6 GHz and mmWave
frequencies. The maximization of the successful content delivery probability is
a challenging problem. To tackle it, we first propose a constrained
cross-entropy algorithm which achieves the near-optimal solution with moderate
complexity. We then develop another simple yet effective heuristic
probabilistic content placement scheme, termed two-stair algorithm, which
strikes a balance between caching the most popular contents and achieving
content diversity. Numerical results demonstrate the superior performance of
the constrained cross-entropy method and that the two-stair algorithm yields
significantly better performance than only caching the most popular contents.
The comparisons between the sub-6 GHz and mmWave systems reveal an interesting
tradeoff between caching capacity and density for the mmWave system to achieve
similar performance as the sub-6 GHz system.Comment: 14 pages; Accepted to appear in IEEE Transactions on Wireless
Communication
- …