19 papers
Quantitative Infrared Thermographic Assessment of Hand Cooling Dynamics During Controlled Contact with Metal Plates
Pengfei Zhu, Hai Zhang, Stefano Sfarra +4
This study investigates the spatiotemporal thermal response of human hands during controlled contact cooling using short wave infrared (SWIR), mid wave infrared (MWIR), and long wa…
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…
Analytic Continuation Between Real- and Imaginary-Time Quantum Dynamics and the Fundamental Instability of Inverse Reconstruction
Pengfei Zhu
We develop a unified spectral-semigroup framework that connects real-time and imaginary-time quantum dynamics through analytic continuation. Within this formulation, evolution is e…
Non-Hermitian Exceptional Dynamics in First-Order Heat Transport
Pengfei Zhu
Heat transport exhibits distinct regimes ranging from ballistic propagation to diffusive relaxation, traditionally described by disparate theoretical frameworks. Here, we introduce…