中文
相关论文

相关论文: Modelling an equivalent b-value in diffusion-weigh…

200 篇论文

Pulsed field gradient (PFG) has been increasingly employed to study anomalous diffusions in Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging (MRI). However, the analysis of PFG anomalous diffusion is complicated. In this…

化学物理 · 物理学 2016-11-01 Guoxing Lin

Analytical diffusion models offer a mathematically transparent path to generative modeling by formulating the denoising score as an empirical-Bayes posterior mean. However, this interpretability comes at a prohibitive cost: the standard…

机器学习 · 计算机科学 2026-02-19 Xinyi Shang , Peng Sun , Jingyu Lin , Zhiqiang Shen

We consider a nonparametric Bayesian approach to estimate the diffusion coefficient of a stochastic differential equation given discrete time observations over a fixed time interval. As a prior on the diffusion coefficient, we employ a…

统计理论 · 数学 2020-07-22 Shota Gugushvili , Frank van der Meulen , Moritz Schauer , Peter Spreij

Diffusion-weighted magnetic resonance imaging (DW-MRI) is a critical imaging method for capturing and modeling tissue microarchitecture at a millimeter scale. A common practice to model the measured DW-MRI signal is via fiber orientation…

We suggest to utilize the rich information content about microstructural tissue properties entangled in asymmetric balanced steady-state free precession (bSSFP) profiles to estimate multiple diffusion metrics simultaneously by neural…

Inferring a diffusion equation from discretely-observed measurements is a statistical challenge of significant importance in a variety of fields, from single-molecule tracking in biophysical systems to modeling financial instruments.…

机器学习 · 统计学 2023-12-12 Yinuo Ren , Yiping Lu , Lexing Ying , Grant M. Rotskoff

Probabilistic diffusion models have achieved state-of-the-art results for image synthesis, inpainting, and text-to-image tasks. However, they are still in the early stages of generating complex 3D shapes. This work proposes Diffusion-SDF, a…

计算机视觉与模式识别 · 计算机科学 2023-03-17 Gene Chou , Yuval Bahat , Felix Heide

Sub-surface scattering is key to our perception of translucent materials. Models based on diffusion theory are used to render such materials in a realistic manner by evaluating an approximation of the material BSSRDF at any two points of…

图形学 · 计算机科学 2016-09-08 Etienne Ferrier

Score-based diffusion models currently constitute the state of the art in continuous generative modeling. These methods are typically formulated via overdamped or underdamped Ornstein--Uhlenbeck-type stochastic differential equations, in…

机器学习 · 计算机科学 2025-12-22 Herlock Rahimi

Diffusion tensor imaging provides important information on tissue structure and orientation of fiber tracts in brain white matter in vivo. It results in diffusion tensors, which are $3\times3$ symmetric positive definite (SPD) matrices,…

应用统计 · 统计学 2013-04-17 Ying Yuan , Hongtu Zhu , Martin Styner , John H. Gilmore , J. S. Marron

In this paper, a novel gamma-shadowed two-ray with diffuse power (GS-TWDP) composite fading model is proposed. The model is intended for modeling propagation in the emerging wireless networks working at millimeter wave (mmWave) frequencies,…

信号处理 · 电气工程与系统科学 2022-03-07 Pamela Njemcevic , Almir Maric

Using a discrete wavelet based space-scale decomposition (SSD), the spectrum of the skewness and kurtosis is developed to describe the non-Gaussian signatures in cosmologically interesting samples. Because the basis of the discrete wavelet…

天体物理学 · 物理学 2007-05-23 Jesus Pando , Li-Zhi Fang

The Drift-Diffusion Model (DDM) is widely used in neuropsychological studies to understand the decision process by incorporating both reaction times and subjects' responses. Various models have been developed to estimate DDM parameters,…

应用统计 · 统计学 2025-07-03 Zekai Jin , Yaakov Stern , Seonjoo Lee

Diffusion-driven flow is a boundary layer flow arising from the interplay of gravity and diffusion in density-stratified fluids when a gravitational field is non-parallel to an impermeable solid boundary. This study investigates…

流体动力学 · 物理学 2024-09-23 Lingyun Ding

Partially-observed data collected by sampling methods is often being studied to obtain the characteristics of information diffusion networks. However, these methods usually do not consider the behavior of diffusion process. In this paper,…

社会与信息网络 · 计算机科学 2014-05-30 Motahareh Eslami Mehdiabadi , Hamid R. Rabiee , Mostafa Salehi

Purpose: Oscillating gradient spin-echo (OGSE) diffusion MRI provides information about the microstructure of biological tissues via the frequency dependence of the apparent diffusion coefficient (ADC). ADC dependence on OGSE frequency has…

医学物理 · 物理学 2019-09-26 Aidin Arbabi , Jason Kai , Ali R Khan , Corey A Baron

When particles/molecules diffuse in systems that contain obstacles, the steady-state regime (during which the mean-square displacement scales linearly with time, $\left< r^2 \right> \sim t$) is preceded by a transient regime. It is common…

生物物理 · 物理学 2021-08-12 Nicholas Ilow , Gary W. Slater

Diffusion models typically inject isotropic Gaussian noise, disregarding structure in the data. Motivated by the way quantum squeezed states redistribute uncertainty according to the Heisenberg uncertainty principle, we introduce Squeezed…

机器学习 · 计算机科学 2025-11-19 Jyotirmai Singh , Samar Khanna , James Burgess

Diffusion models excel at capturing the natural design spaces of images, molecules, DNA, RNA, and protein sequences. However, rather than merely generating designs that are natural, we often aim to optimize downstream reward functions while…

This paper uses dynamical invariants to describe the evolution of collisionless systems subject to time-dependent gravitational forces without resorting to maximum-entropy probabilities. We show that collisionless relaxation can be viewed…

星系天体物理 · 物理学 2015-06-03 Jorge Peñarrubia
‹ 上一页 1 2 3 10 下一页 ›