8 papers
Can Deep Learning Achieve Cross-Physics Mapping?
Pengfei Zhu, Julien Lecompagnon, Mathias Ziegler
Can deep learning translate physical fields governed by fundamentally different equations? We address this question by introducing Cross-Physics Mapping (CPM), an operator-learning…
Spectral Geometry and Dispersion-Constrained Projection of Diffusive Fields
Pengfei Zhu, Julien Lecompagnon, Philipp Daniel Hirsch +1
Diffusive fields obey operator-imposed relations between spatial structure and temporal decay, yet conventional spectral filtering selects components primarily according to frequen…
Structured Illumination Scanning Thermography (SISTER)
Pengfei Zhu, Julien Lecompagnon, Philipp Daniel Hirsch +1
Conventional non-invasive photothermal imaging techniques are fundamentally constrained by the diffusive nature of heat transport, which causes severe energy dissipation during sub…
Generalized Virtual-Wave Theory for Photothermal Coherence Tomography under Arbitrary Excitation Toward Non-Contact Industrial Inspection of Composite Materials
Pengfei Zhu, Julien Lecompagnon, Philipp Daniel Hirsch +1
Photothermal imaging is a powerful noncontact and nondestructive technique for subsurface inspection of composite materials, yet its performance is fundamentally limited by the dif…
A Unified Framework for Virtual Wave Transform: From Generalized Formulation to Excitation-Specific Projection
Pengfei Zhu, Julien Lecompagnon, Philipp Daniel Hirsch +1
We present a unified theoretical framework for the mapping between diffusive and wave-like dynamics, formulated as a spectral integral operator acting on temporal fields. By introd…
The Spectral Domain Snell Law in Diffusion-Wave Fields
Pengfei Zhu, Julien Lecompagnon, Philipp Daniel Hirsch +2
Snell law is traditionally regarded as a hallmark of phase-propagating phenomena such as optical, acoustic, elastic, electromagnetic, and quantum waves. In contrast, purely diffusi…
Generalized virtual wave reconstruction for vibrothermography: Overcoming the wavefront-free behavior and quantification challenges in the diffusion-wave field
Pengfei Zhu, Julien Lecompagnon, Mathias Ziegler +2
Wavefront-free behavior and the resulting quantification difficulties are intrinsic limitations of vibrothermography due to the diffusive nature of thermal fields. This work propos…
Thermographic detection of internal defects using 2D photothermal super resolution reconstruction with sequential laser heating
Julien Lecompagnon, Samim Ahmadi, Philipp Hirsch +2
Thermographic photothermal super resolution reconstruction enables the resolution of internal defects/inhomogeneities below the classical limit which is governed by the diffusion p…