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Chenwei Shao

Publications and source records attributed to Chenwei Shao.

2 recordsLinked to original sources

Removing Motion Artifact in MRI by Using a Perceptual Loss Driven Deep Learning Framework

Purpose: Deep learning-based MRI artifact correction methods often demonstrate poor generalization to clinical data. This limitation largely stems from the inability of deep learning models in reliably distinguishing motion artifacts from true anatomical structures, due to insufficient awareness of artifact characteristics. To address this challenge, we proposed PERCEPT-Net, a deep learning framework that enhances structure preserving and suppresses artifact through dedicated perceptual supervision.Method: PERCEPT-Net is built on a residual U-Net backbone and incorporates three auxiliary components. The first multi-scale recovery module is designed to preserve both global anatomical context and fine structural details, while the second dual attention mechanisms further improve performance by prioritizing clinically relevant features. At the core of the framework is the third Motion Perceptual Loss (MPL), an artifact-aware perceptual supervision strategy that learns generalized representations of MRI motion artifacts, enabling the model to effectively suppress them while maintaining anatomical fidelity. The model is trained on a hybrid dataset comprising both real and simulated paired volumes, and its performance is validated on a prospective test set using a combination of quantitative metrics and qualitative assessments by experienced radiologists.Result: PERCEPT-Net outperformed state-of-the-art methods on clinical data. Ablation studies identified the Motion Perceptual Loss as the primary contributor to this performance, yielding significant improvements in structural consistency and tissue contrast, as reflected by higher SSIM and PSNR values. These findings were further corroborated by radiologist evaluations, which demonstrated significantly higher diagnostic confidence in the corrected volumes.

cs.CV

Atomistic insight into the effects of solute and pressure on phase transformation in titanium alloys

The phase stability and transformation between hexagonal close-packed (hcp) {\alpha}-phase and body-centered cubic (bcc) \b{eta}-phase in titanium (Ti) alloys are critical to their mechanical properties and manufacturing processes for engineering applications. However, many factors, both intrinsic and extrinsic (e.g., solute elements and external pressures, respectively), may govern their phase transformations dynamically, which is crucial to the design of new Ti alloys with desirable properties. In this work, we study the effects of various solute elements and external hydrostatic pressures on the solid-state phase transformations in Ti alloys using density functional theory (DFT) and nudged elastic band (NEB) calculations. The results show that both alloying and applied pressure reduce transformation barriers, with Al and Mo being most effective under ambient conditions, while Nb, V, Zr, and Sn show enhanced transformation kinetics under stress. Solute-induced modifications to the local electronic structure and bonding environment, particularly under pressure, contribute to variations in phase stability. We identify a synergistic interaction between solute effects and external stress, which facilitates phase transitions that are unachievable under static conditions. These findings provide atomistic insights into the coupled chemical-mechanical mechanisms underlying phase transformations in Ti alloys with improved phase stability and mechanical performance.

cond-mat.mtrl-sci