Materials Research at Shanghai Jiao Tong University

Abstract

Transformer architectures have exhibited remarkable performance in image super-resolution (SR). Since the quadratic computational complexity of the self-attention (SA) in Transformer, existing methods tend to adopt SA in a local region to reduce overheads. However, the local design restricts the global context exploitation, which is critical for accurate image reconstruction. In this work, we propose the Recursive Generalization Transformer (RGT) for image SR, which can capture global spatial information and is suitable for high-resolution images. Specifically, we propose the recursive-generalization self-attention (RG-SA). It recursively aggregates input features into representative feature maps, and then utilizes cross-attention to extract global information. Meanwhile, the channel dimensions of attention matrices (query, key, and value) are further scaled for a better trade-off between computational overheads and performance. Furthermore, we combine the RG-SA with local self-attention to enhance the exploitation of the global context, and propose the hybrid adaptive integration (HAI) for module integration. The HAI allows the direct and effective fusion between features at different levels (local or global). Extensive experiments demonstrate that our RGT outperforms recent state-of-the-art methods.

Microstructure and Micro Strain in the CGHAZ of 2.25Cr-1.6W Steel after Intercritical Heat Treatment

“…It is reported that the recrystallization in Ni-based alloy (such as FM52 alloy) effectively reduces the DDC susceptibility. 18) In order to supplement the results of previous study, the phase transformation products and micro strain led by recrystallization in the CGHAZ of 2.25Cr-1.6W steel were analyzed in this study by x-ray diffraction (XRD), optical microscope (OM), scanning electron microscope (SEM), transmission electron microscope (TEM), electron backscatter diffraction (EBSD), and transmission-EBSD (T-EBSD). Moreover, the roles of recrystallization of these two types of cracking were compared.…”

“…ferent Materials Systems Though recrystallization had been reported to effectively reduce the high temperature cracking susceptibility in Ni-based alloy 18) and heat resistant steel, 7) the mechanisms might be different. In this section, these two different materials systems were compared.…”

“…These two factors led to different cracking characteristics. In Inconel 690 alloy, strain concentrated at austenite grain boundaries, 18) which led to the crack nucleated at austenite grain boundaries and propagated to the triple junctions. In 2.25Cr-1.6W heat resistant steel, strain concentrates at newly former recrystallized grain boundaries (Fig.…”

Nonlinear DOB-based explicit NMPC for station-keeping of a multi-vectored propeller airship with thrust saturation

“…The kinematics models of the airship (21) are where ϕ, θ, and ψ are the pitch, the yaw, and roll angles, respectively. ½ x g y g z g is the position in ERF.…”

Rectilinear-motion space inversion-based detection approach for infrared dim air targets with variable velocities

“…Consequently, the noise in pixels of IR image is also independent. Second, when researching the IR noise characters, Chen 24 obtains a conclusion that noise in short term and local window can approximately be viewed as temporal and spatial stationary Gaussian noise. These above two points illustrate that the noise in IR images is independent and identically distributed and they subject to Gaussian distribution.…”