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Purpose: A novel subspace-based reconstruction method for frequency-modulated balanced steady-state free precession (fmSSFP) MRI is presented. In this work, suitable data acquisition schemes, subspace sizes, and efficiencies for banding…

MRI systems are traditionally engineered to produce close to idealized performance, enabling a simplified pulse sequence design philosophy. An example of this is control of eddy currents produced by gradient fields; usually these are…

Balanced steady-state free precession (bSSFP) imaging enables high scan efficiency in MRI, but differs from conventional sequences in terms of elevated sensitivity to main field inhomogeneity and nonstandard T2/T1-weighted tissue contrast.…

图像与视频处理 · 电气工程与系统科学 2021-08-12 Kübra Keskin , Uğur Yılmaz , Tolga Çukur

Summary: Errors in gradient trajectories introduce significant artifacts and distortions in magnetic resonance images, particularly in non-Cartesian imaging sequences, where imperfect gradient waveforms can greatly reduce image quality.…

医学物理 · 物理学 2025-06-19 Jonathan B. Martin , Hannah E. Alderson , John C. Gore , Mark D. Does , Kevin D. Harkins

Balanced steady-state free precession (bSSFP) can be used as an alternative to gradient-echo (GE) EPI for BOLD functional MRI when image distortions and signal drop-outs are severe such as at ultra-high field. However, 3D-bSSFP acquisitions…

医学物理 · 物理学 2019-06-26 Olivier Reynaud , Analina R. da Silva , Rolf Gruetter , Ileana O. Jelescu

Purpose: Quantitative magnetization transfer (qMT) imaging can be used to quantify the proportion of protons in a voxel attached to macromolecules. Here, we show that the original qMT balanced steady-state free precession (bSSFP) model is…

医学物理 · 物理学 2022-07-22 Fritz M. Bayer , Peter Jezzard , Michael Bock , Alex K. Smith

Accurate blur estimation is essential for high-performance imaging across various applications. Blur is typically represented by the point spread function (PSF). In this paper, we propose a physics-informed PSF learning framework for…

计算机视觉与模式识别 · 计算机科学 2025-03-12 Liqun Chen , Yuxuan Li , Jun Dai , Jinwei Gu , Tianfan Xue

Gradient-based approximate inference methods, such as Stein variational gradient descent (SVGD), provide simple and general-purpose inference engines for differentiable continuous distributions. However, existing forms of SVGD cannot be…

机器学习 · 计算机科学 2020-03-03 Jun Han , Fan Ding , Xianglong Liu , Lorenzo Torresani , Jian Peng , Qiang Liu

Diffusion models (DMs) excel in image generation but suffer from slow inference and training-inference discrepancies. Although gradient-based solvers for DMs accelerate denoising inference, they often lack theoretical foundations in…

计算机视觉与模式识别 · 计算机科学 2026-02-04 Shigui Li , Wei Chen , Delu Zeng

We present a variational Bayesian method of joint image reconstruction and point spread function (PSF) estimation when the PSF of the imaging device is only partially known. To solve this semi-blind deconvolution problem, prior…

数据分析、统计与概率 · 物理学 2013-03-18 Se Un Park , Nicolas Dobigeon , Alfred O. Hero

Diffusion models have shown remarkable promise for image restoration by leveraging powerful priors. Prominent methods typically frame the restoration problem within a Bayesian inference framework, which iteratively combines a denoising step…

计算机视觉与模式识别 · 计算机科学 2025-09-04 Hongjie Wu , Mingqin Zhang , Linchao He , Ji-Zhe Zhou , Jiancheng Lv

By chaining a sequence of differentiable invertible transformations, normalizing flows (NF) provide an expressive method of posterior approximation, exact density evaluation, and sampling. The trend in normalizing flow literature has been…

机器学习 · 计算机科学 2020-10-20 Robert Giaquinto , Arindam Banerjee

Point spread function (PSF) engineering is vital for precisely controlling the focus of light in computational imaging, with applications in neural imaging, fluorescence microscopy, and biophotonics. The PSF is derived from the magnitude of…

光学 · 物理学 2025-04-22 Aleksey Valouev

In this paper, we study a novel second-order energy stable Backward Differentiation Formula (BDF) finite difference scheme for the epitaxial thin film equation with slope selection (SS). One major challenge for the higher oder in time…

数值分析 · 数学 2017-06-29 Wenqiang Feng , Cheng Wang , Steven M. Wise , Zhengru Zhang

Recent advancements in diffusion models have been effective in learning data priors for solving inverse problems. They leverage diffusion sampling steps for inducing a data prior while using a measurement guidance gradient at each step to…

机器学习 · 计算机科学 2025-04-02 Rayhan Zirvi , Bahareh Tolooshams , Anima Anandkumar

Score-based stochastic denoising models have recently been demonstrated as powerful machine learning tools for conditional and unconditional image generation. The existing methods are based on a forward stochastic process wherein the…

We propose a bootstrapping framework to quantify uncertainty in time-frequency representations (TFRs) generated by the short-time Fourier transform (STFT) and the STFT-based synchrosqueezing transform (SST) for oscillatory signals with…

统计方法学 · 统计学 2026-01-28 Hau-Tieng Wu , Zhou Zhou

This paper describes a gradient-descent based optimization algorithm for synthesizing Multi-Tone Sinusoidal Frequency Modulated (MTSFM) waveforms with low Auto-Correlation Function (ACF) sidelobes in a specified region of time delays while…

信号处理 · 电气工程与系统科学 2023-04-25 David G. Felton , David A. Hague

Purpose: Determine the correct mathematical phase description for balanced steady-state free precession (bSSFP) signals in multicompartment systems. Theory and Methods: Based on published bSSFP signal models, two distinct phase descriptions…

Recent advances in NeRF inpainting have leveraged pretrained diffusion models to enhance performance. However, these methods often yield suboptimal results due to their ineffective utilization of 2D diffusion priors. The limitations…

计算机视觉与模式识别 · 计算机科学 2024-11-26 Menglin Zhang , Xin Luo , Yunwei Lan , Chang Liu , Rui Li , Kaidong Zhang , Ganlin Yang , Dong Liu
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