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This study introduces a novel method to investigate in-situ light transport within optically thick ensembles of cold atoms, exploiting the internal structure of alkaline-earth metals. A method for creating an optical excitation at the…

Integrable systems in low dimensions, constructed through the symmetry reduction method, are studied using phase portrait and variable separation techniques. In particular, invariant quantities and explicit periodic solutions are…

solv-int · 物理学 2009-10-31 J. A. Calzada , M. A. del Olmo , M. A. Rodriguez

The existence of topological invariants analogous to Chern/Pontryagin classes for a standard $SO(D)$ or $SU(N)$ connection, but constructed out of the torsion tensor, is discussed. These invariants exhibit many of the features of the…

高能物理 - 理论 · 物理学 2009-10-30 Osvaldo Chandia , Jorge Zanelli

The light elemental solutes B, C, N, and O can penetrate the surface of Mg alloys and diffuse during heat treatment or high temperature application, forming undesirable compounds. We investigate the diffusion of these solutes by determining…

材料科学 · 物理学 2016-08-15 Ravi Agarwal , Dallas R. Trinkle

In this paper, we introduce a denoising diffusion algorithm to discover microstructures with nonlinear fine-tuned properties. Denoising diffusion probabilistic models are generative models that use diffusion-based dynamics to gradually…

机器学习 · 计算机科学 2023-06-14 Nikolaos N. Vlassis , WaiChing Sun

Limited by the encoder-decoder architecture, learning-based edge detectors usually have difficulty predicting edge maps that satisfy both correctness and crispness. With the recent success of the diffusion probabilistic model (DPM), we…

计算机视觉与模式识别 · 计算机科学 2024-01-10 Yunfan Ye , Kai Xu , Yuhang Huang , Renjiao Yi , Zhiping Cai

To study axonal microstructure with diffusion MRI, axons are typically modeled as straight impermeable cylinders, whereby the transverse diffusion MRI signal can be made sensitive to the cylinder's inner diameter. However, the shape of a…

医学物理 · 物理学 2020-08-18 Hong-Hsi Lee , Sune N. Jespersen , Els Fieremans , Dmitry S. Novikov

Metasurfaces are ultra-thin optical elements composed of engineered sub-wavelength structures that enable precise control of light. Their inverse design - determining a geometry that yields a desired optical response - is challenging due to…

光学 · 物理学 2025-06-30 Liav Hen , Erez Yosef , Dan Raviv , Raja Giryes , Jacob Scheuer

This paper describes a predictive control method to search for unstable periodic orbits of the generalized tent map. The invariant set containing periodic orbits is a repelling set with a complicated Cantor-like structure. Therefore, a…

Anisotropic light transport is extremely common among scattering materials, yet a comprehensive picture of how macroscopic diffusion is determined by microscopic tensor scattering coefficients is not fully established yet. In this work, we…

This article is a description of elasticity theory for readers with mathematical background. The first sections are an abridgment of parts of the book by Marsden and Hughes, including a compact identification of the equations of motion as…

数学物理 · 物理学 2013-12-25 James Mathews

We analyze the well-posedness of an anisotropic, nonlocal diffusion equation. Establishing an equivalence between weighted and unweighted anisotropic nonlocal diffusion operators in the vein of unified nonlocal vector calculus, we apply our…

偏微分方程分析 · 数学 2021-01-13 Marta D'Elia , Mamikon Gulian

We introduce a new measure of instability of area-preserving twist diffeomorphisms, which generalizes the notions of angle of splitting of separatrices, and flux through a gap of a Cantori. As an example of application, we establish a sharp…

动力系统 · 数学 2017-03-07 Sinisa Slijepcevic

Diffusion models (DMs) have emerged as the new state-of-the-art family of deep generative models. To gain deeper insights into the limitations of diffusion models in recommender systems, we investigate the fundamental structural disparities…

信息检索 · 计算机科学 2025-04-11 Meng Yuan , Yutian Xiao , Wei Chen , Chu Zhao , Deqing Wang , Fuzhen Zhuang

Rotation-invariance is a desired property of machine-learning models for medical image analysis and in particular for computational pathology applications. We propose a framework to encode the geometric structure of the special Euclidean…

计算机视觉与模式识别 · 计算机科学 2020-02-21 Maxime W. Lafarge , Erik J. Bekkers , Josien P. W. Pluim , Remco Duits , Mitko Veta

Anisotropic mesh adaptation is studied for the linear finite element solution of eigenvalue problems with anisotropic diffusion operators. The M-uniform mesh approach is employed with which any nonuniform mesh is characterized…

数值分析 · 数学 2020-04-20 Jingyue Wang , Weizhang Huang

We introduce an integrodifferential extension of the edge-enhancing anisotropic diffusion model for image denoising. By accumulating weighted structural information on multiple scales, our model is the first to create anisotropy through…

图像与视频处理 · 电气工程与系统科学 2021-05-18 Tobias Alt , Joachim Weickert

Dielectric tensor tomography (DTT) enables the reconstruction of three-dimensional (3D) dielectric tensors, which provides a physical measure of 3D optical anisotropy. Herein, we present a cost-effective and robust method for DTT…

光学 · 物理学 2022-12-14 Juheon Lee , Seungwoo Shin , Herve Hugonnet , Yongkeun Park

To design semiconductor-based optical devices, the optical properties of the used semiconductor materials must be precisely measured over a large band. Transmission spectroscopy stands out as an inexpensive and widely available method for…

We present here a new stochastic modelling in the constitution of fluid flow reduced-order models. This framework introduces a spatially inhomogeneous random field to represent the unresolved small-scale velocity component. Such a…

流体动力学 · 物理学 2017-09-20 Valentin Resseguier , Etienne Mémin , Dominique Heitz , Bertrand Chapron