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Purpose: The importance of robust proton treatment planning to mitigate the impact of uncertainty is well understood. However, its computational cost grows with the number of uncertainty scenarios, prolonging the treatment planning process.…

Medical Physics · Physics 2023-05-01 Anqi Fu , Vicki T. Taasti , Masoud Zarepisheh

$\textbf{Purpose:}$ To assess the viability of a physics-based, deterministic and adjoint-capable algorithm for performing treatment planning system independent dose calculations and for computing dosimetric differences caused by anatomical…

Medical Physics · Physics 2024-04-02 Tiberiu Burlacu , Danny Lathouwers , Zoltán Perkó

Particle physics simulations are the cornerstone of nuclear engineering applications. Among them radiotherapy (RT) is crucial for society, with 50% of cancer patients receiving radiation treatments. For the most precise targeting of tumors,…

Machine Learning · Computer Science 2021-09-10 Oscar Pastor-Serrano , Zoltán Perkó

Online adaptive proton therapy (APT) is an ideal solution theoretically, which however is challenging to proton clinics. Although multiple groups have been endeavoring to develop online APT technology, there is a concern in the radiotherapy…

We devise the fast adjoint response algorithm for the gradient of physical measures (long-time-average statistics) of discrete-time hyperbolic chaos with respect to many system parameters. Its cost is independent of the number of…

Dynamical Systems · Mathematics 2022-09-13 Angxiu Ni

We compute, from first principles, the absolute dose or fluence distribution per incident proton charge in a known heterogeneous terrain exposed to known proton beams. The algorithm is equally amenable to scattered or scanned beams. All…

Medical Physics · Physics 2016-10-05 Bernard Gottschalk

We present and mathematically analyze an online adjoint algorithm for the optimization of partial differential equations (PDEs). Traditional adjoint algorithms would typically solve a new adjoint PDE at each optimization iteration, which…

Optimization and Control · Mathematics 2022-01-27 Justin Sirignano , Konstantinos Spiliopoulos

Dose calculations in proton therapy require the fast and accurate solution of a high-dimensional transport equation for a large number of (pencil) beams with different energies and directions. Deterministically solving this transport…

Numerical Analysis · Mathematics 2025-08-07 Pia Stammer , Niklas Wahl , Jonas Kusch , Danny Lathouwers

Delineation of tumors and organs-at-risk permits detecting and correcting changes in the patients' anatomy throughout the treatment, making it a core step of adaptive proton therapy (APT). Although AI-based auto-contouring technologies have…

We propose an oAPT workflow that incorporates all these functionalities and validate its clinical implementation feasibility with prostate patients. AI-based auto-segmentation tool AccuContourTM (Manteia, Xiamen, China) was seamlessly…

Objective: Real-time adaptive proton range verification systems based on produced neutrons require accurate information on their non-isotropic momentum distributions within short times, for which Monte Carlo (MC) methods are too…

This comprehensive study delves into the intricate interplay between protons and organic polymers, offering insights into proton therapy in cancer treatment. Focusing on the influence of the spatial electron density distribution on stopping…

Proton therapy provides superior dose conformity compared with photon radiotherapy, concentrating radiation within the tumor while sparing adjacent healthy tissue. This advantage has been most effectively realized for static tumors in…

Medical Physics · Physics 2025-10-09 Vivek Maradia , Nick Yue , Adam Molzahn , Jingqian Wang , Mark Pankuch , Serdar Charyyev , Billy W. Loo

Uncertainty quantification and sensitivity analyses are a vital component for predictive modeling in the sciences and engineering. The adjoint approach to sensitivity analysis requires solving a primary system of equations and a…

Computational Physics · Physics 2016-12-08 Kelli D. Humbird , Ryan G. McClarren

An adjoint formulation leveraging a physics-informed neural network (PINN) is employed to advance the density moment of a runaway electron (RE) distribution forward in time. A distinguishing feature of this approach is that once the adjoint…

Plasma Physics · Physics 2024-12-18 Christopher J. McDevitt , Jonathan Arnaud , Xian-Zhu Tang

Motivated by recent applications of superdiffusive transport models to shock-accelerated particle distributions in the heliosphere, we solve analytically a one-dimensional fractional diffusion-advection equation for the particle density. We…

Space Physics · Physics 2015-06-23 Yuri E. Litvinenko , Frederic Effenberger

We present a stabilised finite element method for modelling proton transport in tissue, incorporating both inelastic energy loss and elastic angular scattering. A key innovation is a positivity-preserving formulation that guarantees…

Numerical Analysis · Mathematics 2025-06-03 Ben S. Ashby , Abdalaziz Hamdan , Tristan Pryer

In this paper we present a method for estimating unknown parameter that appear in a two dimensional nonlinear reaction-diffusion model of cancer invasion. This model considers that tumor-induced alteration of microenvironmental pH provides…

Optimization and Control · Mathematics 2014-05-21 A. A. I. Quiroga , D. R. Fernandez , G. A. Torres , C. V. Turner

In this paper, we develop a self-adaptive ADMM that updates the penalty parameter adaptively. When one part of the objective function is strongly convex i.e., the problem is semi-strongly convex, our algorithm can update the penalty…

Optimization and Control · Mathematics 2023-10-03 Tianyun Tang , Kim-Chuan Toh

In neuroscience, the distribution of a decision time is modelled by means of a one-dimensional Fokker--Planck equation with time-dependent boundaries and space-time-dependent drift. Efficient approximation of the solution to this equation…

Numerical Analysis · Mathematics 2023-02-08 Udo Boehm , Sonja Cox , Gregor Gantner , Rob Stevenson
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