English
Related papers

Related papers: The fixed-point iteration method for IMRT optimiza…

200 papers

The complexity of human cancer often results in significant heterogeneity in response to treatment. Precision medicine offers potential to improve patient outcomes by leveraging this heterogeneity. Individualized treatment rules (ITRs)…

Radiotherapy (RT) is a critical cancer treatment, with volumetric modulated arc therapy (VMAT) being a commonly used technique that enhances dose conformity by dynamically adjusting multileaf collimator (MLC) positions and monitor units…

Medical Physics · Physics 2025-06-26 Stefanos Achlatis , Efstratios Gavves , Jan-Jakob Sonke

Coordination of distributed agents is required for problems arising in many areas, including multi-robot systems, networking and e-commerce. As a formal framework for such problems, we use the decentralized partially observable Markov…

Artificial Intelligence · Computer Science 2014-01-16 Daniel S. Bernstein , Christopher Amato , Eric A. Hansen , Shlomo Zilberstein

We develop a fixed-point iterative algorithm that computes the matrix projection with respect to the Bures distance on the set of positive definite matrices that are invariant under some symmetry. We prove that the fixed-point iteration…

Quantum Physics · Physics 2025-12-23 Shrigyan Brahmachari , Roberto Rubboli , Marco Tomamichel

Background: Multi-collimator proton minibeam radiation therapy (MC-pMBRT) has recently emerged as a versatile technique for dose shaping, enabling peak-valley dose patterns in organs-at-risk (OAR) while maintaining a uniform dose…

Medical Physics · Physics 2025-02-25 Nimita Shinde , Weijie Zhang , Yuting Lin , Hao Gao

The matrix rank minimization problem has applications in many fields such as system identification, optimal control, low-dimensional embedding, etc. As this problem is NP-hard in general, its convex relaxation, the nuclear norm minimization…

Optimization and Control · Mathematics 2011-01-04 Donald Goldfarb , Shiqian Ma

Today, intensity-modulated radiation therapy (IMRT) is one of the methods used to treat brain tumors. In conventional treatment planning methods, after identifying planning target volume (PTV), and organs at risk (OARs), and determining the…

Quantitative Methods · Quantitative Biology 2023-05-15 Mobina Naeemi , Mohamad Reza Esmaeili , Iraj Abedi

Robust treatment planning algorithms for Intensity Modulated Proton Therapy (IMPT) and Intensity Modulated Radiation Therapy (IMRT) allow for uncertainty reduction in the delivered dose distributions through explicit inclusion of error…

Medical Physics · Physics 2025-10-15 Remo Cristoforetti , Jennifer Josephine Hardt , Niklas Wahl

Purpose: To demonstrate the feasibility of fast Monte Carlo (MC) based inverse biological planning for the treatment of head and neck tumors in spot-scanning proton therapy. Methods: Recently, a fast and accurate Graphics Processor Unit…

Medical Physics · Physics 2016-10-11 H. Wan Chan Tseung , J. Ma , C. R. Kreofsky , D. Ma , C. Beltran

A multiply-accumulate (MAC) operation is the main computation unit for DSP applications. DSP blocks are one of the efficient solutions to implement MACs in FPGA's. However, since the DSP blocks have wide multiplier and adder blocks, MAC…

Hardware Architecture · Computer Science 2021-10-26 Ercan Kalali , Rene van Leuken

In this paper, we develop a novel accelerated fixed-point-based framework using delayed inexact oracles to approximate a fixed point of a nonexpansive operator (or equivalently, a root of a co-coercive operator), a central problem in…

Optimization and Control · Mathematics 2025-12-16 Nghia Nguyen-Trung , Quoc Tran-Dinh

We present a head-to-head evaluation of the Improved Inexact--Newton--Smart (INS) algorithm against a primal--dual interior-point framework for large-scale nonlinear optimization. On extensive synthetic benchmarks, the interior-point method…

Optimization and Control · Mathematics 2025-11-18 Neda Bagheri Renani , Maryam Jaefarzadeh , Daniel Sevcovic

Recent efforts on solving inverse problems in imaging via deep neural networks use architectures inspired by a fixed number of iterations of an optimization method. The number of iterations is typically quite small due to difficulties in…

Image and Video Processing · Electrical Eng. & Systems 2021-06-04 Davis Gilton , Gregory Ongie , Rebecca Willett

Cancer is a primary cause of morbidity and mortality worldwide. The radiotherapy plays a more and more important role in cancer treatment. In the radiotherapy, the dose distribution maps in patient need to be calculated and evaluated for…

Medical Physics · Physics 2019-10-18 Zhao Peng , Hongming Shan , Tianyu Liu , Xi Pei , Jieping Zhou , Ge Wang , X. George Xu

In many iterative optimization methods, fixed-point theory enables the analysis of the convergence rate via the contraction factor associated with the linear approximation of the fixed-point operator. While this factor characterizes the…

Systems and Control · Electrical Eng. & Systems 2022-06-22 Trung Vu , Raviv Raich

For optimal power flow problems with chance constraints, a particularly effective method is based on a fixed point iteration applied to a sequence of deterministic power flow problems. However, a priori, the convergence of such an approach…

Optimization and Control · Mathematics 2023-12-13 Johannes J. Brust , Mihai Anitescu

The purpose of this study is to examine in a clinical setting a novel formulation of objective functions for intensity-modulated radiotherapy treatment plan multicriteria optimization (MCO) that we suggested in a recent study. The proposed…

Optimization and Control · Mathematics 2018-10-24 Lovisa Engberg , Kjell Eriksson , Anders Forsgren

Neural operators serve as fast, data-driven surrogates for scientific modeling but typically rely on a monolithic, single-pass inference procedure that struggles to resolve high-frequency details, a limitation known as spectral bias. We…

Machine Learning · Computer Science 2026-05-27 Xiaotian Liu , Shuyuan Shang , Xiaopeng Wang , Pu Ren , Yaoqing Yang

Targeting at the development of an accurate and efficient dose calculation engine for online adaptive radiotherapy, we have implemented a finite size pencil beam (FSPB) algorithm with a 3D-density correction method on GPU. This new…

Medical Physics · Physics 2015-05-27 Xuejun Gu , Urszula Jelen , Jinsheng Li , Xun Jia , Steve B. Jiang

In distributed model predictive control (DMPC), where a centralized optimization problem is solved in distributed fashion using dual decomposition, it is important to keep the number of iterations in the solution algorithm, i.e. the amount…

Optimization and Control · Mathematics 2013-07-11 Pontus Giselsson , Anders Rantzer