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Zhuohang He

Publications and source records attributed to Zhuohang He.

3 recordsLinked to original sources

Improved Turbo Message Passing for Compressive Robust Principal Component Analysis: Algorithm Design and Asymptotic Analysis

Compressive Robust Principal Component Analysis (CRPCA) naturally arises in various applications as a means to recover a low-rank matrix low-rank matrix $\boldsymbol{L}$ and a sparse matrix $\boldsymbol{S}$ from compressive measurements. In this paper, we approach the problem from a Bayesian inference perspective. We establish a probabilistic model for the problem and develop an improved turbo message passing (ITMP) algorithm based on the sum-product rule and the appropriate approximations. Additionally, we establish a state evolution framework to characterize the asymptotic behavior of the ITMP algorithm in the large-system limit. By analyzing the established state evolution, we further propose sufficient conditions for the global convergence of our algorithm. Our numerical results validate the theoretical results, demonstrating that the proposed asymptotic framework accurately characterize the dynamical behavior of the ITMP algorithm, and the phase transition curve specified by the sufficient condition agrees well with numerical simulations.

cs.IT

Proton-CAT: a Novel Strategy for Enhanced Proton Therapy

We present a nitrogen-targeting-Proton-Carbon-Alpha-Therapy method, abbreviated as Proton-CAT, which partially converts protons into carbon-12 and $α$ particles through nuclear reactions between protons and nitrogen-15. Monte Carlo simulations validated the effectiveness of the Proton-CAT, and the study specifically focused on the distribution of relative energy deposition. The results indicated that the presence of nitrogen-15 enhanced the maximum dose level of protons, resulting in more effective damage confined to tumor cells. Statistical analysis of secondary ions has shown that the Proton-CAT significantly increases the production efficiencies of carbon-12 and $α$ particles. Furthermore, it has been revealed that elevating the nitrogen-15 concentration significantly boosts the dose of carbon and $α$ particles within the tumor region. The present work would contribute to the future development of proton therapy.

physics.med-ph

Effect of the ${\rm^{15}N(p,α)^{12}C}$ reaction on the kinetic energy release of water molecule fragmentation

In this work, we investigated the effect of ${\rm^{15}N(p,α)^{12}C}$ reaction produced by the collision between proton and ammonia monohydrate on the kinetic energy release (KER) of water molecule fragmentation. After the occurrence of the nuclear reaction, it was found that the charge states $q$ and the flight speeds $v$ are the main factors affecting the KER of water molecule fragmentation. With the value of $q/v$ increases, the KER distribution gets wider and the peak position changes more pronounced. The energy gained by each fragment is related to the mass of the fragment and the distance of the fragment from the nuclear reaction. In this study, the fragments with smaller masses and the distances far away from the nuclear reaction get higher energies. The fragments of water molecules getting higher energy may induce other factors affecting the radiotherapy effect, which needs more detailed investigations in the future.

physics.chem-ph