Beijing University of Posts and Telecommunications

About: Beijing University of Posts and Telecommunications is a education organization based out in Beijing, Beijing, China. It is known for research contribution in the topics: MIMO & Quality of service. The organization has 39576 authors who have published 41525 publications receiving 403759 citations. The organization is also known as: BUPT.

Simulations of Quantum Transport in Sub-5-nm Monolayer Phosphorene Transistors

Abstract: Phosphorene is a promising channel material for next-generation electronics, due to its unique in-plane anisotropy, large density of states near the valence-band maximum, and high carrier mobility. Using $a\phantom{\rule{0}{0ex}}b$ $i\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}o$ quantum transport simulations, the authors investigate very small, double-gated MOSFETs based on monolayer phosphorene. It is predicted that these transistors can fulfill industrial requirements for ON current, delay time, and power dissipation until the gate length is scaled down to 2 nm.

Mobility Change in Two Types of Metamorphic Parallel Mechanisms

Abstract: This paper presents a new joint coined as the rT joint and proposes two types of metamorphic parallel mechanisms assembled with this rT joint. In the first type, the mechanism changes its topology by turning the rT joints in all limbs into different configurations. This change in mobility is completed by two cases illustrated by a 3(rT)PS metamorphic parallel mechanism having variable mobility from 3 to 6 and a 3(rT)P(rT) parallel mechanism having various configurations including pure translations, pure rotations, and mobility 4. In the second type, a central strut with the rT joint is added in a parallel mechanism. The variable mobility of the mechanism results from the topological change of the central (rT)P(rT) strut. This is illustrated in a 3SPS-1 (rT)P(rT) metamorphic parallel mechanism, which changes its mobility from 4 to 5. It is demonstrated in mobility analysis that the change in local mobility of each limb results in the change in the platform mobility that a metamorphic process can be achieved. This particular analysis leads to advancement of improved Grubler-Kutzbach criterion by introducing the local mobility factor in the mobility analysis.

Depth-Wise Separable Convolutions and Multi-Level Pooling for an Efficient Spatial CNN-Based Steganalysis

Abstract: For steganalysis, many studies showed that convolutional neural network (CNN) has better performances than the two-part structure of traditional machine learning methods. Existing CNN architectures use various tricks to improve the performance of steganalysis, such as fixed convolutional kernels, the absolute value layer, data augmentation and the domain knowledge. However, some designing of the network structure were not extensively studied so far, such as different convolutions (inception, xception, etc.) and variety ways of pooling(spatial pyramid pooling, etc.). In this paper, we focus on designing a new CNN network structure to improve detection accuracy of spatial-domain steganography. First, we use $3\times 3$ kernels instead of the traditional $5\times 5$ kernels and optimize convolution kernels in the preprocessing layer. The smaller convolution kernels are used to reduce the number of parameters and model the features in a small local region. Next, we use separable convolutions to utilize channel correlation of the residuals, compress the image content and increase the signal-to-noise ratio (between the stego signal and the image signal). Then, we use spatial pyramid pooling (SPP) to aggregate the local features and enhance the representation ability of features by multi-level pooling. Finally, data augmentation is adopted to further improve network performance. The experimental results show that the proposed CNN structure is significantly better than other five methods such as SRM, Ye-Net, Xu-Net, Yedroudj-Net and SRNet, when it is used to detect three spatial algorithms such as WOW, S-UNIWARD and HILL with a wide variety of datasets and payloads.

Multiple plasmon-induced transparencies in coupled-resonator systems.

Abstract: Multiple plasmon-induced transparencies are numerically predicted in an ultracompact plasmonic structure, comprising series of stub resonators side-coupled with a metal-isolator-metal waveguide. Because of the phase-coupled effect, electromagnetically induced transparency (EIT)-like spectral response occurs between two adjacent stub resonators with detuned resonant wavelengths. In this approach, multiple EIT-like spectral responses, with bandwidths of the order of several nanometers, are obtained in the plasmonic structure with a small footprint of about 0.6 μm2. An analytic model and the relative phase analysis based on the scattering matrix theory are used to explain this phenomenon.