Huawei

About: Huawei is a company organization based out in Shenzhen, China. It is known for research contribution in the topics: Terminal (electronics) & Signal. The organization has 41417 authors who have published 44698 publications receiving 343496 citations. The organization is also known as: Huawei Technologies & Huawei Technologies Co., Ltd..

Forensics feature analysis in quaternion wavelet domain for distinguishing photographic images and computer graphics

Abstract: In this paper, a novel set of features based on Quaternion Wavelet Transform (QWT) is proposed for digital image forensics. Compared with Discrete Wavelet Transform (DWT) and Contourlet Wavelet Transform (CWT), QWT produces the parameters, i.e., one magnitude and three angles, which provide more valuable information to distinguish photographic (PG) images and computer generated (CG) images. Some theoretical analysis are done and comparative experiments are made. The corresponding results show that the proposed scheme achieves 18 percents’ improvements on the detection accuracy than Farid’s scheme and 12 percents than Ozparlak’s scheme. It may be the first time to introduce QWT to image forensics, but the improvements are encouraging.

Actional-Structural Graph Convolutional Networks for Skeleton-based Action Recognition

Abstract: Action recognition with skeleton data has recently attracted much attention in computer vision. Previous studies are mostly based on fixed skeleton graphs, only capturing local physical dependencies among joints, which may miss implicit joint correlations. To capture richer dependencies, we introduce an encoder-decoder structure, called A-link inference module, to capture action-specific latent dependencies, i.e. actional links, directly from actions. We also extend the existing skeleton graphs to represent higher-order dependencies, i.e. structural links. Combing the two types of links into a generalized skeleton graph, we further propose the actional-structural graph convolution network (AS-GCN), which stacks actional-structural graph convolution and temporal convolution as a basic building block, to learn both spatial and temporal features for action recognition. A future pose prediction head is added in parallel to the recognition head to help capture more detailed action patterns through self-supervision. We validate AS-GCN in action recognition using two skeleton data sets, NTU-RGB+D and Kinetics. The proposed AS-GCN achieves consistently large improvement compared to the state-of-the-art methods. As a side product, AS-GCN also shows promising results for future pose prediction.

Review of polymer materials with low dielectric constant

Abstract: One of the exciting and promising developments in material science today is the design and synthesis of novel low-dielectric-constant polymer materials, which are found to have potential applications in the field of ultralarge-scale integration, capacitors and other electronic circuits as insulating and/or dielectric materials. In this article the new polymer dielectric materials reported in recent years are reviewed, including aromatic (heteroaromatic) polymers, silicon-containing polymers, fluorinated polymers, porous polymers, etc. In summarizing the review, the development, potential applications and future directions of polymer materials with low dielectric constant are discussed. Copyright © 2010 Society of Chemical Industry

26 m/5.5 Gbps air-water optical wireless communication based on an OFDM-modulated 520-nm laser diode

Abstract: We experimentally demonstrate a high-speed air-water optical wireless communication system with both downlink and uplink transmission employing 32-quadrature amplitude modulation (QAM) orthogonal frequency division multiplexing (OFDM) and a single-mode pigtailed green-light laser diode (LD). This work is an important step towards the future study on optical wireless communications between underwater platforms and airborne terminals. Over a 5-m air channel and a 21-m water channel, we achieve a 5.3-Gbps transmission without power loading (PL) and a 5.5-Gbps transmission with PL in the downlink. The corresponding bit error rates (BERs) are 2.64×10-3 and 2.47×10-3, respectively, which are below the forward error correction (FEC) criterion. A data rate of 5.5 Gbps with PL at a BER of 2.92×10-3 is also achieved in the uplink.

Placing dynamic content in caches with small population

Abstract: This paper addresses a fundamental limitation for the adoption of caching for wireless access networks due to small population sizes. This shortcoming is due to two main challenges: making timely estimates of varying content popularity and inferring popular content from small samples. We propose a framework which alleviates such limitations. To timely estimate varying popularity in a context of a single cache we propose an Age-Based Threshold (ABT) policy which caches all contents requested more times than a threshold N (τ), where τ is the content age. We show that ABT is asymptotically hit rate optimal in the many contents regime, which allows us to obtain the first characterization of the optimal performance of a caching system in a dynamic context. We then address small sample sizes focusing on L local caches and one global cache. On the one hand we show that the global cache learns L times faster by aggregating all requests from local caches, which improves hit rates. On the other hand, aggregation washes out local characteristics of correlated traffic which penalizes hit rate. This motivates coordination mechanisms which combine global learning of popularity scores in clusters and Least-Recently-Used (LRU) policy with prefetching.