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2606.09335 2026-06-09 eess.AS 新提交

Factors affecting ASR performance: A study using state of the art ASR models in Indic Languages

影响ASR性能的因素:使用最先进的ASR模型在印度语言中的研究

Agneedh Basu, Pavan Kumar J, Pranav Bhat, Sujith Pulikodan, Visruth Sanka, Nihar Desai, Prasanta Kumar Ghosh

AI总结 本研究通过多种开源ASR模型在零样本设置下对印度语言语音数据集进行大规模分析,探讨语言、说话者和声学因素对词错误率的影响,揭示了跨语言模式与语言特定敏感性。

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AI中文摘要

ASR性能因语言、说话者和录音条件而异,但对印度语言的系统分析仍然有限。我们提出了一个大规模研究,对多个开源ASR模型在零样本设置下对多样化印度语音数据集的解码输出进行评估。我们分析了印地语、孟加拉语、卡纳达语、泰卢固语和马拉地语的语言、说话者水平和声学因素。我们检查了WER与说话者特征(如平均词长、说话速率和话语持续时间)在多个模型-数据集对上的相关性。对于印地语,我们进一步分析了音频因素,包括电话编解码器、位深度、重采样和背景噪声。结果揭示了跨语言模式和语言特定的敏感性,展示了说话者行为和信号处理选择如何影响真实世界印度场景中ASR的鲁棒性。

英文摘要

ASR performance varies across languages, speakers, and recording conditions, yet systematic analysis for Indic languages remain limited. We present a large-scale study of decoded outputs from multiple open-source ASR models evaluated on diverse Indian speech datasets in zero-shot settings. We analyze linguistic, speaker-level, and acoustic factors across Hindi, Bengali, Kannada, Telugu, and Marathi. We examine correlations between WER and speaker traits such as average word length, speaking rate, and utterance duration across multiple model dataset pairs. For Hindi, we further analyze audio factors including telephone codecs, bit depth, resampling, and background noise. Results reveal both cross lingual patterns and language-specific sensitivities, showing how speaker behavior and signal processing choices affect ASR robustness in real world Indic scenarios.

2606.09333 2026-06-09 physics.flu-dyn 新提交

Studies of PHP with CASCO code and its experimental validation

利用CASCO代码研究脉动热管及其实验验证

Vadim Nikolayev, Slaven Bajić, Guillaume Boudier, Eric Blondé, Typhaine Coquard, Mauro Abela, Mauro Mameli, Sauro Filippeschi

AI总结 通过CASCO代码研究脉动热管中表面性质和停歇对稳态运行的影响,发现成核壁垒存在最优值使热阻最小,并解释了停歇机制及热阻随加热负载降低的原因。

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Journal ref
Joint 23rd IHPC and 17th IHPS, May 2026, Gda{ń}sk, Poland
AI中文摘要

我们在此讨论与脉动(振荡)热管(PHP)稳态运行相关的两个主要问题:表面性质和停歇的影响。它们通过CASCO模拟软件(Code Avancé de Simulation du Caloduc Oscillant:高级PHP模拟代码,法语)版本4进行研究。针对两个不同原型进行了实验验证。第一个原型还用于研究成核壁垒(气泡成核所需的壁面过热度)的影响,该壁垒反映了壁面润湿性和粗糙度。发现存在一个最优的成核壁垒值,在该值下,对于给定的蒸发器功率,热阻达到最小值。运行状态是连续的,显示压力波沿整个PHP通道传播。对于小壁垒和大壁垒,都观察到停歇状态。第二个实验装置(PHP智能回路)用于研究停歇状态。发现其特点是快速压力增长(对应于振荡)的混沌重复序列,随后是停歇期间较慢的压力衰减。热阻随加热负载的降低归因于液膜收缩更快导致的停歇时间减少。

英文摘要

We discuss here two major issues related to the steady functioning of the pulsating (oscillating) heat pipe (PHP): the effect of the surface properties and stopovers. They are studied with the CASCO simulation software (Code Avanc{é} de Simulation du Caloduc Oscillant: Advanced PHP Simulation Code in French) version 4. Its experimental validation against two different prototypes is presented. The first is used also to study the effect of the nucleation barrier (the wall superheating necessary for the bubble nucleation) that reflects the wall wettability and roughness. An optimal value of the nucleation barrier is found where the thermal resistance achieves a minimum for a given evaporator power. The functioning regime is continuous showing pressure waves propagating along all the PHP channel. The stopover regime is observed both for small and large barriers. The second experimental setup (PHP Smart Loop) is used to study the stopover regime. It is found that it is characterized by a chaotically repeating sequence of fast pressure growth (corresponding to oscillations) followed by a slower pressure decay during a stopover. The decrease of the thermal resistance with heating load is explained by a decrease of the stopover time caused by a faster liquid film shrinking.

2606.09332 2026-06-09 eess.SP 新提交

Wearable Single-Lead ECG Detects Fine-Grained Structural Heart Disease Through Echo-Report Supervision

可穿戴单导联心电图通过超声报告监督检测细粒度结构性心脏病

Chenyang He, Qinghao Zhao, Shun Huang, Jun Li, Gongzheng Tang, Hao Zhang, Tong Liu, Zhengkai Xue, Jian Liu, Kangyin Chen, Cheng Ding, Shenda Hong

AI总结 提出AnyECG-Echo框架,利用单导联心电图与超声报告对比预训练,在外部队列中检测13种细粒度结构性心脏病亚型,实现高AUROC并具备双轴可解释性。

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AI中文摘要

结构性心脏病(SHD)是心力衰竭和心血管死亡的主要原因,但由于超声心动图的可及性有限,早期检测仍受到限制。虽然单导联心电图(ECG)通过可穿戴设备无处不在,但现有的人工智能筛查模型通常依赖于12导联输入,跨机构泛化能力差,或需要大量特定条件的标注数据集。最近的研究证明了在单一医疗系统内对单导联心电图和超声心动图报告进行对比预训练的可行性。在这里,我们提出了AnyECG-Echo,一个通过三个关键进展将这一范式推向临床转化的框架:(1)在地理独立的外部队列(n=16,621)中进行评估;(2)诊断覆盖13种细粒度SHD亚型,包括心肌、心腔、瓣膜和大血管病变;(3)双轴机制可解释性,结合基于电生理学的Shapley归因与定量测量的新兴相关性。在总计n=25,222的验证队列中,该模型对高影响亚型表现出高AUROC,包括左心室收缩功能降低(AUROC 0.866-0.924)、全心扩大(0.877-0.931)和二尖瓣狭窄(0.836-0.906)。此外,我们成功验证了模型输出与既定医学生理特征的一致性,从而增强了可解释性。值得注意的是,我们发现AnyECG-Echo的输出作为基于生理学的数字生物标志物,能够准确跟踪LVEF和心肌壁厚度等客观指标。这些发现证明可穿戴单导联心电图可以有效检测细粒度结构性心脏病,为人群规模筛查提供了实用解决方案。

英文摘要

Structural heart disease (SHD) is a primary driver of heart failure and cardiovascular mortality, yet early detection remains constrained by the limited accessibility of echocardiography. While single-lead electrocardiogram (ECG) is ubiquitous through wearables, existing AI screening models often depend on 12-lead inputs, generalize poorly across institutions, or require massive, condition-specific labeled datasets. Recent work has demonstrated the feasibility of contrastive pre-training between single-lead ECGs and echocardiography reports within a single health system. Here, we present AnyECG-Echo, a framework that advance this paradigm toward clinical translation through three key developments: (1) evaluation in a geographically independent external cohort (n = 16,621); (2) diagnostic coverage of 13 fine-grained SHD subtypes spanning myocardial, chamber, valvular, and great-vessel pathologies; and (3) dual-axis mechanistic interpretability combining electrophysiology-grounded Shapley attribution with emergent correlations to quantitative measurements. Across validation cohorts totaling n = 25,222, the model demonstrated high AUROC for high-impact subtypes, including reduced left ventricular systolic function (AUROC 0.866-0.924), global heart enlargement (0.877-0.931), and mitral stenosis (0.836-0.906). Furthermore, we successfully validated the alignment of model outputs with established medical physiological traits, thereby enhancing interpretability. Notably, we discovered that AnyECG-Echo's outputs function as physiologically grounded digital biomarkers that accurately track objective metrics such as LVEF and myocardial wall thickness. These findings prove that wearable single-lead ECGs can effectively detect fine-grained structural heart disease, offering a practical solution for population-scale screening.

2606.09330 2026-06-09 eess.IV 新提交

Dynamic XR Rendering Offloading Based on Feature-Based Quality Assessment

基于特征质量评估的动态XR渲染卸载

Sige Liu, Zhe Wang, Lavish Kamal Kumar, Yansha Deng

AI总结 提出一种边缘辅助XR渲染测试平台,利用基于深度特征嵌入和余弦相似度的感知质量指标,结合上下文赌博机学习控制器,动态优化渲染卸载决策以平衡感知质量和延迟。

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AI中文摘要

扩展现实(XR)应用需要密集计算和低延迟,尤其是实时渲染任务。本文提出一个边缘辅助的XR渲染测试平台,该平台根据网络条件和延迟约束,在XR客户端和边缘服务器之间动态卸载渲染工作负载。该测试平台集成了Microsoft HoloLens 2头显、支持GPU的边缘服务器以及基于HOLO Stream SDK定制的远程渲染工具包,实现了本地和边缘渲染模式之间的实时无缝切换。为了克服头部运动和异步帧到达下像素级质量指标的局限性,我们提出了一种基于深度特征嵌入和余弦相似度的感知评估指标,该指标对空间和时间错位具有鲁棒性。此外,我们设计了一个上下文赌博机学习控制器,通过联合优化感知质量和延迟来实时调整渲染放置决策。实验结果表明了该测试平台的可行性和性能,验证了其在提供高质量交互式XR体验方面的有效性。

英文摘要

Extended Reality (XR) applications demand intensive computation and low latency, especially for real-time rendering tasks. In this letter, we present an edge-aided XR rendering testbed that dynamically offloads rendering workloads between the XR client and the edge server built upon network conditions and latency constraints. The testbed integrates a Microsoft HoloLens 2 headset, a GPU-enabled edge server, and a customized remote rendering toolkit based on the HOLO Stream SDK, enabling seamless switching between local and edge rendering modes in real time. To overcome the limitations of pixel-level quality metrics under head movements and asynchronous frame arrivals, we propose a perceptual evaluation metric based on deep feature embeddings and cosine similarity, which remains robust to spatial and temporal misalignments. Furthermore, we design a contextual bandit learning controller to adapt rendering placement decisions in real time by jointly optimizing perceptual quality and latency. Experimental results demonstrate the feasibility and performance of our testbed, validating its effectiveness in delivering high-quality and interactive XR experiences.

2606.09329 2026-06-09 math.LO 新提交

A hyperamalgamation property

超融合性质

Paolo Lipparini

AI总结 提出超融合性质,证明格、半格、布尔代数和对偶海廷代数具有该性质,并应用于带算子的代数结构融合性。

Comments 17 pages

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AI中文摘要

超融合性质是融合性质的加强,已在代数逻辑中得到许多应用,最近也在模型论中得到应用。这里我们引入一个更强的概念,称为超融合性质。我们证明格、半格、布尔代数和双海廷代数具有超融合性质。作为第一个应用,我们得到了带有进一步算子的半格、布尔代数和海廷代数的融合性质。

英文摘要

The superamalgamation property is a strengthening of the amalgamation property and has found many applications in algebraic logic, more recently, also in model theory. Here we introduce an even stronger notion we call the hyperamalgamation property. We show that lattices, semilattices, Boolean algebras and dual Heyting algebras have the hyperamalgamation property. As a first application, we obtain the amalgamation property for semilattices, Boolean algebras and Heyting algebras with further operators.

2606.09328 2026-06-09 math.ST math.PR stat.TH 新提交

Parameter estimation in generalized fractional neuronal models

广义分数阶神经元模型中的参数估计

Pauliina Ilmonen, Milla Laurikkala, Enrica Pirozzi, Luigia Caputo, Lauri Viitasaari

AI总结 针对结合分数阶动力学与相关随机输入的广义随机分数阶神经元模型,提出基于离散观测的两步参数估计方法,利用Mittag-Leffler函数渐近行为和分数阶微分技术,推导误差界并分析重建稳定性。

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AI中文摘要

我们研究了一个广义随机分数阶神经元模型,该模型结合了分数阶动力学与相关随机输入。所提出的框架由分数阶微分方程描述,该方程由具有平稳增量和均值回复结构的潜在随机过程驱动。这种公式允许包含短程和长程依赖结构,并自然产生非指数松弛现象。主要目标是基于神经元状态过程的离散观测,开发可行的参数估计程序。我们提出了一种两步方法。首先,通过利用Mittag-Leffler函数在原点附近的渐近行为,估计控制分数阶动力学的参数。随后,通过分数阶微分技术重建潜在随机输入,从而估计控制隐藏噪声动力学的参数。我们推导了估计量的定量误差界,并在驱动噪声的适当正则性假设下分析了潜在过程的重建误差。特别地,分数阶导数的阶数与噪声过程的Hölder正则性之间的相互作用自然出现在重建过程的稳定性分析中。最后,模拟研究说明了所提出方法的适用性,并强调了记忆效应和噪声正则性对统计推断质量的影响。结果支持分数阶随机分析对于具有记忆和相关输入的神经元系统的建模和推断的相关性。

英文摘要

We investigate a generalized stochastic fractional neuronal model combining fractional dynamics with correlated stochastic inputs. The proposed framework is described by a fractional differential equation driven by a latent stochastic process with stationary increments and mean-reverting structure. This formulation allows the inclusion of both short-range and long-range dependence structures and naturally produces non-exponential relaxation phenomena. The main goal is the development of a feasible parameter estimation procedure based on discrete observations of the neuronal state process. We propose a two-step methodology. First, the parameters governing the fractional dynamics are estimated by exploiting the asymptotic behavior of Mittag-Leffler functions near the origin. Subsequently, the latent stochastic input is reconstructed through fractional differentiation techniques, allowing the estimation of the parameters governing the hidden noise dynamics. We derive quantitative error bounds for the estimators and analyze the reconstruction error of the latent process under suitable regularity assumptions on the driving noise. In particular, the interplay between the order of the fractional derivative and the Hölder regularity of the noise process naturally emerges in the stability analysis of the reconstruction procedure. Finally, simulation studies illustrate the applicability of the proposed methodology and highlight the influence of memory effects and noise regularity on the quality of statistical inference. The results support the relevance of fractional stochastic analysis for the modeling and inference of neuronal systems with memory and correlated inputs.

2606.09326 2026-06-09 math.OC 新提交

Generalized Cancellation of Capacitor Parasitic Inductance Using a Lattice Network and Its Application to Common-Mode Noise Reduction

利用格型网络广义消除电容器寄生电感及其在共模噪声抑制中的应用

Katsuya Nomura, Shuhei Chizuwa, Takashi Masuzawa

AI总结 提出一种基于格型网络的广义电容器寄生电感消除技术,通过Z矩阵等效变换放宽传统对称条件,并采用非对称格型网络仅需调节一个电感即可实现消除,进而扩展至共模扼流圈噪声抑制。

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AI中文摘要

本文提出了一种利用格型网络消除电容器寄生电感的广义技术。基于Z矩阵的等效变换表明,传统的垂直对称电感条件仅为充分条件,可以放宽。进而提出了一种垂直非对称格型网络,通过仅调节一个电感即可消除电容器的寄生电感。该方法进一步扩展至使用共模扼流圈的共模噪声抑制,两个概念均得到了实验验证。

英文摘要

This letter presents a generalized technique for cancelling the parasitic inductance of capacitors using a lattice network. The Z-matrix-based equivalent transformation shows that the conventional vertically symmetric inductance condition is only a sufficient condition and can be relaxed. A vertically asymmetric lattice network is then proposed, enabling the parasitic inductance of capacitors to be cancelled by adjusting only one inductance. The method is further extended to common-mode noise reduction using a common-mode choke, and both concepts are experimentally verified.

2606.09325 2026-06-09 astro-ph.GA 新提交

A Unified Ionization Framework for the Spectroscopic Diversity of Tidal Disruption Events

潮汐瓦解事件光谱多样性的统一电离框架

Lars L. Thomsen, Lixin Dai, Daniel Kasen, Enrico Ramirez-Ruiz, Panos Charalampopoulos, Giorgos Leloudas, Brenna Mockler

AI总结 提出统一辐射传输框架,通过电离状态调控成功复现TDE四种光谱类型,揭示电子散射是极端谱线宽度的主导机制。

Comments Submitted to APJ Letter

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AI中文摘要

光学潮汐瓦解事件(TDE)展现出极宽的发射线(约$10^3$-$10^4~{\rm km~s^{-1}}$),并在观测上被分为四种光谱类型:H主导、He主导、H+He和无特征。普遍的H+He类常显示鲍恩荧光谱线(特别是\niii~和\oiii),这些特征在活动星系核中很少见,其起源至今仍不清楚。我们提出了首个统一的辐射转移框架,通过模拟太阳成分的光学厚外流包层,再现了所有四种TDE光谱类别。我们的模型成功捕捉了连续谱性质和关键光谱特征,包括强\ha、\heii~和鲍恩发射。我们证明TDE的光谱多样性主要由气体电离状态决定,而电离状态受注入光度与包层质量之比控制。随着电离水平降低,观测到的光谱类别序列自然出现,从无特征过渡到He主导、鲍恩主导,最终到H主导光谱。我们进一步表明,光学厚外流中的电子散射是导致极端谱线宽度的主导机制,将谱线轮廓直接与风的物理性质联系起来。该模型还解释了观测到的与光度、黑洞质量的相关性,以及TDE演化过程中光谱分类的相对稳定性。这项工作为TDE光谱学建立了统一的物理框架,提供了对这些瞬变事件的发射机制、能量学和外流结构的新见解,并为解释和拟合观测光谱提供了实用途径。

英文摘要

Optical tidal disruption events (TDEs) exhibit extremely broad emission lines ($\approx 10^3$-$10^4~{\rm km~s^{-1}}$) and are observationally classified into four spectroscopic types: H-dominated, He-dominated, H+He, and featureless. The prevalent H+He class often displays Bowen fluorescence lines (notably \niii~and \oiii), features that are rarely observed in active galactic nuclei and whose origin has remained poorly understood. We present the first unified radiative transfer framework that reproduces all four TDE spectroscopic classes using simulations of optically thick, outflowing envelopes with solar composition. Our models successfully capture both the continuum properties and key spectral features, including strong \ha, \heii~and Bowen emissions. We demonstrate that the spectroscopic diversity of TDEs is primarily governed by the gas ionization state, controlled by the ratio of injected luminosity to envelope mass. As the ionization level decreases, the observed sequence of spectroscopic classes emerges naturally, transitioning from featureless to He-dominated, to Bowen-dominated, and finally to H-dominated spectra. We further show that electron scattering in the optically thick outflow is the dominant mechanism responsible for the extreme line widths, linking line profiles directly to the physical properties of the wind. The model also explains the observed correlations with luminosity, black hole mass, and the relative stability of spectral classifications during TDE evolution. This work establishes a unified physical framework for TDE spectroscopy, providing new insight into the emission mechanisms, energetics, and outflow structure of these transient events, and offering a practical pathway for interpreting and fitting observed spectra.

2606.09324 2026-06-09 hep-ph hep-ex hep-lat nucl-ex nucl-th 新提交

Space- and time-like electromagnetic form factors of the $\mathbfΩ$ baryon

$\Omega$ 重子的类空和类时电磁形状因子

L. Albino, B. Almeida-Zamora, A. Bashir, J. J. Cobos-Martínez, K. Raya, J. Segovia

AI总结 利用基于矢量-矢量接触相互作用的禁闭、对称保持框架,通过彩虹-梯形截断的Dyson-Schwinger方程和庞加莱协变的Faddeev方程,预言了$\Omega$重子在类空和类时区域的弹性电磁形状因子,揭示了夸克质量和SU(3)味对称性对重子结构的影响。

Comments 13 pages, 8 figures, 2 tables

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AI中文摘要

我们给出了在类空和类时区域内$\Omega$重子弹性电磁形状因子的预言,这些计算是在一个基于矢量$\\,\otimes\\,$矢量接触相互作用的禁闭、对称保持框架内完成的。计算采用QCD的Dyson-Schwinger方程的彩虹-梯形截断,并结合三夸克束缚态的庞加莱协变Faddeev方程。完全由奇异夸克组成的$\Omega$重子提供了一个特别干净的环境,用于研究夸克质量和SU(3)味对称性在塑造重子结构中的作用。在该方法中,电磁流与Ward-Takahashi恒等式一致地构造,得到与电单极、磁偶极、电四极和磁八极矩相关的四个独立形状因子。我们在广泛的运动学区域内计算这些形状因子,并分析它们在类空和类时区域的行为。得到的$\Omega$重子静态电磁矩和多极形状因子对戴夸克反常磁矩表现出明显的敏感性,特别是在磁性和高阶多极部分。类时形状因子通过对相应类空解进行渐近解析延拓得到,从而可以构造有效形状因子,并将其与现有实验数据和近期唯象分析进行比较。

英文摘要

We present predictions for the elastic electromagnetic form factors of the $Ω$ baryon in both space-like and time-like regions, computed within a confining, symmetry-preserving framework based on a vector$\,\otimes\,$vector contact interaction. The calculation is performed in the rainbow-ladder truncation of QCD's Dyson-Schwinger equations, combined with a Poincaré-covariant Faddeev equation for the three-quark bound state. The $Ω$ baryon, composed solely of strange quarks, provides a particularly clean environment in which to investigate the role of quark mass and SU(3)-flavor symmetry in shaping baryon structure. Within this approach, the electromagnetic current is constructed consistently with the Ward-Takahashi identity, yielding four independent form factors associated with the electric monopole, magnetic dipole, electric quadrupole, and magnetic octupole moments. We compute these form factors over a broad kinematic domain and analyze their behavior in both space-like and time-like regions. The resulting static electromagnetic moments and multipole form factors of the $Ω$ baryon exhibit a visible sensitivity to the dressed-quark anomalous magnetic moment, particularly in the magnetic and higher-order multipole sectors. The time-like form factors are obtained through asymptotic analytic continuation of the corresponding space-like solutions, allowing the construction of the effective form factor and its comparison with available experimental data and recent phenomenological analyses.

2606.09320 2026-06-09 math.SP math.DG 新提交

Near Isospectrality and Spectral Rigidity for Compact Locally Symmetric Manifolds

紧致局部对称流形的近等谱性与谱刚性

Sudhir Pujahari, Punya Plaban Satpathy

AI总结 研究紧致局部对称流形中,拉普拉斯-贝尔特拉米谱在有限集外一致是否必然导致全等谱,并证明谱刚性。

Comments 27 Pages

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AI中文摘要

逆谱问题探讨拉普拉斯-贝尔特拉米谱在多大程度上决定黎曼流形的几何。我们研究一个自然的弱化版本,称为\emph{近等谱性},即两个紧流形的谱在有限集外一致(计入重数)。我们证明,对于固定单连通非正截面曲率对称空间的紧商空间,近等谱性已经迫使完全等谱性。然后我们将此刚性推广到一大类不可约非紧型对称空间的紧商空间。在这个更大的设定中,近等谱性决定了足够的热不变量,以在所考虑的类中识别万有覆盖,然后固定覆盖的刚性结果意味着完全等谱性。因此,在此研究的类中,拉普拉斯谱的最终一致已经迫使完全的谱一致。

英文摘要

The inverse spectral problem asks to what extent the Laplace--Beltrami spectrum determines the geometry of a Riemannian manifold. We study a natural weakening, called \emph{near isospectrality}, in which the spectra of two compact manifolds agree outside a finite set, counted with multiplicity. We prove that for compact quotients of a fixed simply connected symmetric space of nonpositive sectional curvature, near isospectrality already forces full isospectrality. We then extend this rigidity to a broad collection of compact quotients of irreducible symmetric spaces of noncompact type. In this larger setting, near isospectrality determines enough heat invariants to identify the universal cover within the class under consideration, and the fixed-cover rigidity result then implies full isospectrality. Thus, within the class studied here, eventual agreement of the Laplace spectrum already forces complete spectral agreement.

2606.09319 2026-06-09 cond-mat.mtrl-sci physics.comp-ph 新提交

Crystal Shape and Lattice Deformation in Powder Diffraction

粉末衍射中的晶体形状与晶格变形

Matteo Leoni, Alberto Leonardi

AI总结 提出一种基于傅里叶变换的通用框架,将晶体域形状变形、晶格变形及形状-晶格相对取向作为独立可精修的张量操作,实现复杂形状与各向异性变形的统一建模,并通过虚拟实验验证了高精度恢复。

Comments Submitted for publication to the Journal of Applied Crystallography

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AI中文摘要

精确模拟衍射峰形状对于从纳米晶材料中提取微观结构信息至关重要。公共体积函数广泛用于描述粉末衍射中的有限尺寸和形状展宽,但其解析表达式仅适用于有限的理想几何形状。本文介绍了一个通用的基于傅里叶的框架,其中晶体域形状变形、晶格变形以及形状-晶格相对取向被处理为统一形式主义中独立可精修的张量操作。该方法允许晶体形状和晶格基矢的连续仿射变换,同时保持方向傅里叶系数的解析评估。因此,复杂的颗粒形状、各向异性变形以及形状与晶格之间的任意相对取向可以在单个倒易空间和实空间框架内建模,包括传统粉末衍射线形方法无法处理的耦合形状-晶格变换。该形式主义可应用于单个衍射峰、完整粉末图谱以及全散射形状校正。针对虚拟散射实验数据的验证表明,晶体尺寸、形状、晶格变形以及形状-晶格相对取向可以同时高精度地恢复。

英文摘要

Accurate modelling of diffraction peak shapes is essential for extracting microstructural information from nanocrystalline materials. Common-volume functions are widely used to describe finite-size and shape broadening in powder diffraction, but analytical expressions are available only for a limited set of ideal geometries. Here, we introduce a generalized Fourier-based framework in which crystal-domain shape deformation, lattice deformation, and relative shape-lattice misorientation are treated as independently refinable tensor operations within a unified formalism. The approach enables continuous affine transformations of both crystal shape and lattice base while preserving analytical evaluation of directional Fourier coefficients. As a result, complex particle shapes, anisotropic deformations, and arbitrary relative orientations between shape and lattice can be modelled within a single reciprocal- and real-space framework, including coupled shape-lattice transformations not accessible using conventional powder diffraction line-profile methods. The formalism can be applied to individual diffraction peaks, full powder patterns, and total-scattering shape corrections. Validation against virtual scattering experiment data demonstrates that crystal size, shape, lattice deformation, and relative shape-lattice orientation can be simultaneously recovered with high accuracy.

2606.09318 2026-06-09 cs.DC cs.DS 新提交

Engineering Scalable Distributed List Ranking

工程化可扩展的分布式列表排名

Peter Sanders, Matthias Schimek, Tim Niklas Uhl, Thomas Weidmann

AI总结 通过改进Sibeyn的稀疏统治集算法,利用间接通信、输入局部性和消息合并,实现在多达24,576个核心上对数十亿元素进行可扩展的列表排名。

Comments 14 pages, 4 figures

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AI中文摘要

列表排名问题是并行计算的经典问题之一,具有非平凡算法和作为解决其他问题的子程序的许多应用。虽然在并行计算的早期阶段得到了深入研究,但在过去20年中进展甚微。特别是,关于将列表排名扩展到大型机器和输入规模的工作很少。我们从四分之一世纪前Sibeyn的开创性成果出发重新审视列表排名。我们采用算法和性能工程来改进他的稀疏统治集算法,使其能够扩展到许多处理器,并更详细地分析算法参数的影响,进一步指导我们的实际实现。我们对具有不同结构特性的各种输入实例进行了广泛的实验研究。我们证明,利用间接通信、输入局部性和消息合并,可以在多达24,576个核心上扩展到数十亿个元素。

英文摘要

The list ranking problem is one of the classical problems of parallel computing, with nontrivial algorithms and many applications as a subroutine for solving other problems. While it has been intensively studied in the early days of parallel computing, few things happened in the last 20 years. In particular, there is little work on scaling list ranking to large machines and input sizes. We reconsider list ranking starting from the ground-breaking results of Sibeyn a quarter century ago. We employ algorithm and performance engineering to improve his sparse ruling-set algorithm, making it capable of scaling to many processors, and provide a more detailed analysis of the impact of the algorithm's parameters, further guiding our practical implementation. We perform an extensive experimental study across a variety of input instances with different structural properties. We demonstrate that indirect communication, exploiting input locality, and message coalescing allows scaling to billions of elements on up to 24,576 cores.

2606.09317 2026-06-09 eess.AS 新提交

A Comparative Study of Pre-trained Speech Encoders and Training Objectives for Large-Scale Indic Spoken Language Identification

预训练语音编码器与训练目标在大规模印度语种口语识别中的比较研究

Agneedh Basu, Pavan Kumar J, Sujith P, Visruth Sanka, Nihar Desai, Prasanta Kumar Ghosh

AI总结 本文系统比较了Whisper和FastConformer两种预训练语音编码器结合线性分类器在42种印度语言口语识别中的表现,评估了交叉熵、监督对比损失和层次softmax三种训练目标,发现冻结FastConformer在跨域测试中表现优异,而层次softmax一致优于其他目标。

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AI中文摘要

由于语言数量众多、相关变体间显著的语音重叠以及许多低资源语言标记数据的稀缺,印度语言的口语识别(LID)是一个具有挑战性的问题。在这项工作中,我们系统比较了两种预训练语音编码器——Whisper和FastConformer——与线性分类器结合,用于跨越四个语系的42种语言的大规模印度LID。我们在冻结(线性探测)和微调设置下评估了两种编码器,并比较了三种训练目标:交叉熵(CE)、带交叉熵的监督对比损失(CE+SupCon)和层次softmax(HSM)。模型在Vaani数据集上训练,并在Vaani-Test(留出集)、FLEURS和Kathbath的跨语料设置中评估,提供了领域泛化的见解。冻结的FastConformer编码器在FLEURS和Kathbath上无需任何任务特定适应即达到超过90%的宏准确率,在域外基准上显著优于Whisper,而微调的Whisper在域内表现更强。HSM在所有基准上一致优于CE和CE+SupCon,在域外测试集上增益最大。CE+SupCon降低了FastConformer的跨语料泛化能力,表明对比目标使表示过度特化于域内条件。按语系分析显示,中印度-雅利安变体最难区分,印地语-乌尔都语以及萨德里语-恰蒂斯加尔语-苏古贾语簇是主要的混淆对。

英文摘要

Spoken language identification (LID) for Indian languages is a challenging problem due to the large number of languages, significant phonetic overlap among related varieties, and the scarcity of labeled data for many low-resource languages. In this work, we present a systematic comparative study of two pre-trained speech encoders -- Whisper and FastConformer -- combined with a linear classifier for large-scale Indic LID spanning 42 languages across four linguistic families. We evaluate both encoders in frozen (linear probing) and fine-tuned settings, and compare three training objectives: cross-entropy (CE), supervised contrastive loss with cross entropy (CE + supCon), and hierarchical softmax (HSM). Models are trained on the Vaani dataset and evaluated in a cross-corpus setting on Vaani-Test (held-out), FLEURS, and Kathbath, providing insights into domain generalization. The frozen FastConformer encoder achieves over 90\% macro accuracy on FLEURS and Kathbath without any task-specific adaptation, substantially outperforming Whisper on out-of-domain benchmarks, while fine-tuned Whisper yields stronger in-domain performance. HSM consistently outperforms CE and CE+SupCon for both encoders across all benchmarks, with the largest gains on out-of-domain test sets. CE+SupCon degrades FastConformer's cross-corpus generalization, suggesting that the contrastive objective over-specializes representations to in-domain conditions. Per-family analysis shows that Central Indo-Aryan varieties are the hardest to discriminate, with Hindi--Urdu and the Sadri--Chhattisgarhi--Surgujia cluster being the dominant confusion pairs.

2606.09310 2026-06-09 hep-ph 新提交

Fluctuations and correlations of conserved charges in the Polyakov chiral SU(3) quark mean field model

Polyakov手征SU(3)夸克平均场模型中的守恒荷涨落与关联

Dhananjay Singh, Arvind Kumar

AI总结 在Polyakov手征SU(3)夸克平均场模型中,通过包含真空项计算守恒荷的广义磁化率,揭示了手征与退禁闭相变的分裂特征,并发现高阶导数及非对角关联器对相变信号的敏感性。

Comments 25 pages and 15 figures

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AI中文摘要

我们在包含费米子真空项的Polyakov手征SU(3)夸克平均场(PCQMF)模型中计算了守恒荷的广义磁化率。在$μ_B = 0$ MeV时,计算涵盖了直到八阶的对角线$χ_n^{B,Q,S}$以及所有十二个独立的四阶非对角关联器。扩展到$μ_Q = μ_S = 0$的有限$μ_B$时,我们计算了直到八阶的$χ_n^B$、直到四阶的$χ_n^{Q,S}$、二阶非对角项、所有十二个四阶非对角关联器以及奇阶重子磁化率$χ_1^B$、$χ_3^B$、$χ_5^B$。计算包括真空项(vac=1),并针对独立重新拟合的无海变体(vac=0)重复进行。在$μ_B = 0$ MeV时,手征赝临界温度为$T_{\mathrm{pc}} = 170.5$ MeV(vac=1)和$166.4$ MeV(vac=0),而Polyakov环退禁闭温度为$T_{\mathrm{dec}} = 144.4$ MeV(vac=1)和$146.6$ MeV(vac=0)。在vac=1中,减除的手征凝聚的导数$-dΔ_{l,s}/dT$在$T_{\mathrm{dec}}$附近出现拐点。高阶导数将手征-退禁闭分裂解析为$χ_4^B$和$χ_6^Q$中的双峰、$χ_8^B$和$χ_8^Q$中的双谷以及$χ_6^B$中的多个零点交叉。在四阶非对角关联器中,vac=1的振幅在手征交叉区域的BQ通道中超过vac=0。BS、QS和混合BQS分量在奇异熔化温度附近达到峰值,此时vac=0占主导。沿着$T_{\mathrm{pc}}(μ_B)$,vac=1的峰度比$R_{42}^B \equiv χ_4^B/χ_2^B$在$μ_B/T_{\mathrm{pc}} \approx 2.15$处穿过零,而vac=0在整个范围内保持正值。高阶比$R_{51}^B \equiv χ_5^B/χ_1^B$和$R_{62}^B \equiv χ_6^B/χ_2^B$在vac=1中起始为负,并随着$μ_B$增加而变得更负。

英文摘要

We compute generalized susceptibilities of conserved charges in the Polyakov chiral SU(3) quark mean field (PCQMF) model with the fermion vacuum term. At $μ_B = 0$ MeV, the calculation covers the diagonal $χ_n^{B,Q,S}$ through eighth order and all twelve independent fourth-order off-diagonal correlators. Extending to finite $μ_B$ at $μ_Q = μ_S = 0$, we compute $χ_n^B$ through eighth order, $χ_n^{Q,S}$ through fourth order, the second-order off-diagonals, all twelve fourth-order off-diagonal correlators, and the odd-order baryon susceptibilities $χ_1^B$, $χ_3^B$, $χ_5^B$. The calculation includes the vacuum term (vac=1) and is repeated for an independently refitted no-sea variant (vac=0). At $μ_B = 0$ MeV, the chiral pseudocritical temperature is $T_{\mathrm{pc}} = 170.5$ MeV (vac=1) and $166.4$ MeV (vac=0), while the Polyakov-loop deconfinement temperature is $T_{\mathrm{dec}} = 144.4$ MeV (vac=1) and $146.6$ MeV (vac=0). In vac=1, the derivative $-dΔ_{l,s}/dT$ of the subtracted chiral condensate develops an inflection near $T_{\mathrm{dec}}$. Higher derivative orders resolve the chiral-deconfinement splitting as twin maxima in $χ_4^B$ and $χ_6^Q$, twin minima in $χ_8^B$ and $χ_8^Q$, and multiple zero crossings in $χ_6^B$. Among the fourth-order off-diagonal correlators, vac=1 amplitudes exceed vac=0 in the BQ channel across the chiral crossover. The BS, QS, and mixed BQS components peak near the strange-melting temperature, where vac=0 dominates. Along $T_{\mathrm{pc}}(μ_B)$, the kurtosis ratio $R_{42}^B \equiv χ_4^B/χ_2^B$ of vac=1 crosses zero at $μ_B/T_{\mathrm{pc}} \approx 2.15$, while vac=0 stays positive across the full range. The higher-order ratios $R_{51}^B \equiv χ_5^B/χ_1^B$ and $R_{62}^B \equiv χ_6^B/χ_2^B$ start negative in vac=1 and grow more negative as $μ_B$ increases.

2606.09309 2026-06-09 physics.ins-det astro-ph.IM cond-mat.supr-con 新提交

High-Efficiency Broadband Mid-Infrared Absorption in Asymmetrically Matched Metallic Meanders: Development of Ti40V60 Alloy based LEKIDs for Mid-Far IR

非对称匹配金属曲折线中的高效宽带中红外吸收:基于Ti40V60合金的中远红外LEKID研制

Shilpam Sharma, Shekhar Chandra Pandey, Anudeep Singh, Shankar Lal, R. S. Saini, M. K. Chattopadhyay

AI总结 提出一种无背腔的LEKID吸收器结构,通过匹配曲折线方阻与硅衬底波阻抗抑制反射,并利用亚波长周期束缚倏逝波抑制透射,实现12.5-30微米波段50%-90%的宽带吸收,简化焦平面阵列制备。

Comments 22 Pages, 7 Figures

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AI中文摘要

快速、高灵敏度且宽带的中远红外探测器对于从天体物理到利用红外自由电子激光设施的实验室光源和束线的时间分辨光谱等应用至关重要。传统的集总元件动能电感探测器使用谐振四分之一波长背腔实现高光学效率。然而,这种基于腔的方法本质上是窄带的,并在中远红外波长下面临光机械挑战。本文提出一种完全无背腔的LEKID吸收器结构,实现了超过50%的宽带吸收。曲折线吸收器由超导Ti-V合金制成,并利用印度RRCAT的IR-FEL红外辐射进行表征。通过从硅衬底背面照明并匹配曲折线的方阻与硅衬底的波阻抗,前表面反射被强烈抑制。同时,密集曲折线的亚波长周期通过倏逝波束缚抑制了向自由空间的传播透射。这种组合机制驱动了金属曲折线内高效的欧姆耗散,在12.5-30微米波长范围内实现了50%至90%的实验吸收效率。无腔设计极大地简化了焦平面阵列的制备,同时提供了下一代探测器所需的宽带响应。为了评估Ti40V60合金作为活性超导探测器材料的适用性,还设计、制备并实验表征了一个测试LEKID谐振器。

英文摘要

Fast, highly sensitive, and broadband detectors operating in the mid-to-far-infrared (MIR-FIR) spectral region are essential for applications ranging from astrophysics to time-resolved spectroscopy using laboratory-based sources and beamlines at Infrared Free-Electron Laser (IR-FEL) facilities. Conventional Lumped Element Kinetic Inductance Detectors (LEKID) achieve high optical efficiency using resonant quarter wavelength (λ/4) backshort cavities. However, this cavity-based approach is inherently narrowband and becomes optomechanically challenging at the mid to far infrared (MIR-FIR) wavelengths. Here, we present a completely backshort-free LEKID absorber architecture that achieves broadband absorption exceeding 50%. The meander absorbers were fabricated from a superconducting Ti-V alloy and characterized using IR radiation from the IR-FEL at RRCAT, India. By illuminating through the silicon substrate and matching the meander's sheet resistance to the silicon substrate's wave impedance, the front-side reflection is strongly suppressed. Simultaneously, the sub-wavelength periodicity of the dense meander inhibits propagating transmission into free space via evanescent wave confinement. This combined mechanism drives efficient Ohmic dissipation within the metallic meander, yielding an experimental absorption efficiency ranging from 50% to 90% across the 12.5-30 micrometer wavelength range. The cavity-free design greatly simplifies the fabrication of the focal plane array while providing the broadband response required for next-generation detectors. To assess the suitability of the Ti40V60 alloy as an active superconducting detector material, a test LEKID resonator was also designed, fabricated, and experimentally characterized.

2606.09308 2026-06-09 quant-ph cond-mat.stat-mech hep-th 新提交

Energy Transport in Randomly Coupled Quantum Systems: A Perturbative Approach

随机耦合量子系统中的能量输运:一种微扰方法

Tingfei Li, Runyu Chen

AI总结 通过将耦合建模为高斯随机矩阵,在微扰框架下推导了能量转移率和热导率的显式表达式,并分析了不同态密度下的输运行为。

Comments 28 pages

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AI中文摘要

我们研究了通过随机相互作用耦合的两个量子系统之间的能量输运。我们方法的核心特征是将耦合建模为高斯随机矩阵,这使得简单且系统的微扰展开成为可能。在大$N$极限下,我们推导了耦合强度二阶以内的能量转移率和热导率的显式表达式。利用谱方法和图展开,我们获得了能量转移率的领头阶和次领头阶贡献。我们通过高斯、常数、半圆和伽马态密度的显式计算来说明我们的结果。

英文摘要

We study energy transport between two quantum systems coupled through a random interaction. The central feature of our approach is to model the coupling as a Gaussian random matrix, which enables a simple and systematic perturbative expansion. In the large-$N$ limit, we derive explicit expressions for the energy transfer rate and heat conductance up to second order in the coupling strength. Using spectral methods and diagrammatic expansions, we obtain the leading- and next-to-leading-order contributions to the energy transfer rate. We illustrate our results through explicit calculations for Gaussian, constant, semicircular, and Gamma densities of states.

2606.09307 2026-06-09 stat.ME stat.AP stat.CO 新提交

Robust high-dimensional Bayesian regression with non-Gaussian errors under global--local shrinkage priors

全局-局部收缩先验下非高斯误差的稳健高维贝叶斯回归

Mohammad Arashi

AI总结 针对高维多元回归中非高斯误差问题,提出基于尺度-位置混合误差分布与马蹄+先验的稳健贝叶斯框架,实现系数和残差精度矩阵的联合稀疏性,理论证明后验收缩性和选择一致性,模拟和实证表明优于高斯方法。

Comments 21 pages, 9 figures, 6 tables

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AI中文摘要

具有许多相关响应和预测变量的多元回归通常由于重尾、异常值和不对称性而违反高斯误差假设。高斯过程在系数估计中失去效率,并产生条件依赖图的有偏估计。我们开发了一个稳健的贝叶斯框架,使用尺度-位置混合误差分布,并在回归系数和误差精度矩阵的非对角元素上使用马蹄+全局-局部先验,将回归映射中的稀疏性与残差依赖结构中的稀疏性结合起来。理论贡献包括联合后验收缩、两个支撑集的选择一致性、一个显示马蹄+优于马蹄的Kullback-Leibler风险界,以及有界敏感性,确保在t误差下单个大异常值的影响消失。跨四种误差机制、污染和不同维度的模拟表明,我们的估计量在高斯性下与高斯过程匹配,在重尾和偏斜下优于它们。对FRED-MD宏观经济数据和S&P 500日收益率的应用恢复了可解释的稀疏系数图和残差依赖图,同时自动降低危机时期观测值的权重。

英文摘要

Multivariate regression with many correlated responses and predictors commonly violates Gaussian error assumptions due to heavy tails, outliers, and asymmetry. Gaussian procedures then lose efficiency in coefficient estimation and produce biased estimates of conditional dependence graphs. We develop a robust Bayesian framework using a scale-location mixture error distribution and horseshoe+ global-local priors on both the regression coefficients and off-diagonals of the error precision matrix, coupling sparsity in the regression map with sparsity in the residual dependence structure. Theoretical contributions include joint posterior contraction, selection consistency for both supports, a Kullback-Leibler risk bound showing the dominance of horseshoe+ over horseshoe, and bounded sensitivity, ensuring that a single large outlier has vanishing influence under t errors. Simulations across four error regimes, contamination, and varying dimensions show that our estimator matches Gaussian procedures under normality and dominates them under heavy tails and skewness. Applications to FRED-MD macroeconomic data and S&P 500 daily returns recover interpretable sparse coefficient maps and residual dependence graphs while automatically down-weighting crisis-period observations.

2606.09306 2026-06-09 quant-ph 新提交

Range-controlled entanglement in Lindbladian skin states of monitored fermions

受控费米子的林布拉德皮肤态中的范围控制纠缠

Gianluca Passarelli, Angelo Russomanno, Davide Rossini, Procolo Lucignano

AI总结 通过可调跳跃范围的耗散费米子链,在Gaussian轨迹近似下发现短程跳跃导致完全皮肤积累和面积律纠缠,长程跳跃产生有限体尾和代数子体积律纠缠。

Comments 7 + 9 pages, 4 + 10 figures. Comments are welcome!

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AI中文摘要

储层工程可以稳定在幺正动力学中无法达到的状态。定向粒子守恒耗散产生林布拉德皮肤态,其中泡利不相容将边缘积累转化为多体密度不平衡。在具有可调跳跃范围的受控费米子链中,我们在高斯轨迹近似下识别出两个有限尺寸标度区域:短程跳跃与完全皮肤积累和面积律纠缠一致,而足够长程跳跃产生有限体尾和有效的代数子体积律纠缠。因此,耗散和相干跳跃共同控制皮肤局域化和量子纠缠,突显了它们之间的紧密联系。

英文摘要

Reservoir engineering can stabilize states inaccessible to unitary dynamics. Directed particle-conserving dissipation creates Lindbladian skin states, where Pauli exclusion turns edge accumulation into a many-body density imbalance. In a monitored fermion chain with tunable hopping range, we identify, within a Gaussian trajectory approximation, two finite-size scaling regimes: short-range hopping is consistent with complete skin accumulation and area-law entanglement, whereas sufficiently long-range hopping produces a finite bulk tail and effective algebraic sub-volume-law entanglement. Dissipation and coherent hopping thus jointly control skin localization and quantum entanglement, highlighting their close interconnection.

2606.09305 2026-06-09 math.DG 新提交

Conformal product structures on $S^3$

$S^3$ 上的共形积结构

Xianfeng Jiang

AI总结 利用Reeb叶状结构在$S^3$上构造了共形积结构,这是紧单连通流形上首个非全局积流形构造的共形积结构实例。

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AI中文摘要

我们利用Reeb叶状结构在$S^3$上构造了一个共形积结构。这是紧单连通流形上首个非全局积流形构造的共形积结构实例。

英文摘要

We construct a conformal product structure on $S^3$ using the Reeb foliation. This is the first example of a conformal product structure on a compact simply connected manifold which is not built on a global product manifold.

2606.09302 2026-06-09 math.OC 新提交

Inverse Problems for Costs and Controls in LQG MFGs via Mean Field Trajectories

LQG平均场博弈中基于均值场轨迹的成本与控制逆问题

Grégoire Lambrecht, Mathieu Laurière

AI总结 研究基于均值-协方差轨迹观测的LQG平均场博弈逆问题,提出半定规划方法推断与观测动力学一致的成本参数。

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AI中文摘要

本文研究了完全基于均值-协方差轨迹观测的线性二次高斯(LQG)平均场博弈(MFGs)的逆问题。我们解决了三个顺序挑战:识别观测初始化的最优控制、确定任意初始化的控制、以及恢复一致的成本参数。在温和假设下建立正向纳什均衡的存在唯一性后,我们分析了参数到轨迹映射的单射性,证明其本质上是非单射的,并给出了参数等价的充分条件。我们证明,虽然最优控制在最小假设下对于观测初始化是局部可识别的,但全局可识别性需要更深入地恢复博弈的成本结构。为了弥补这一差距,我们提出了一种构造性的半定规划方法,用于推断与观测群体动力学严格一致的成本参数。数值实验说明了该方法。

英文摘要

This paper investigates inverse problems for Linear-Quadratic-Gaussian (LQG) Mean Field Games (MFGs) based entirely on the observation of mean-covariance trajectories. We address three sequential challenges: identifying the optimal control for observed initializations, determining the control for arbitrary initializations, and recovering consistent cost parameters. After establishing the existence and uniqueness of the forward Nash equilibrium under mild hypotheses, we analyze the injectivity of the parameter-to-trajectory mapping, demonstrating that it is inherently non-injective and providing sufficient conditions for parameter equivalence. We prove that while the optimal control is locally identifiable for observed initializations under minimal assumptions, global identifiability requires a deeper structural recovery of the game's costs. To bridge this gap, we propose a constructive semidefinite programming method to infer cost parameters that are strictly consistent with the observed population dynamics. Numerical experiments illustrate this method.

2606.09300 2026-06-09 math.FA 新提交

Chirp-Induced Non-Separable Gabor Windows on $\mathbb{R}^d$

Chirp诱导的$\mathbb{R}^d$上不可分离的Gabor窗

Lorenzo De Leonardis, Alessandro Mazzoccoli, Pierluigi Vellucci

AI总结 通过将chirp变形应用于可分离格点上的张量积对偶对,构造了$L^2(\mathbb{R}^d)$上显式的不可分离Gabor窗类,保持了紧支撑、光滑性、框架界、精确对偶性等性质,并量化了chirp诱导的耦合。

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AI中文摘要

我们通过将chirp变形应用于可分离格点上的张量积对偶对,构造了$L^2(\mathbb{R}^d)$上一类显式的不可分离Gabor窗。从一维对偶Gabor框架出发,我们首先通过张量积得到可分离的高维对偶对。然后,通过酉chirp算子$U_C f(x)=e^{\pi i x^T Cx}f(x)$及相应的相空间剪切变换,将这些系统变换到形如$\Lambda_{A,B,C}=\{(Ak,CAk+B\ell):k,\ell\in\mathbb{Z}^d\}$的下块三角格点上,得到Gabor系统。该构造保持了紧支撑、光滑性、框架界、精确对偶性、典范对偶以及近似对偶误差。我们还通过相空间协方差缺陷量化了chirp诱导的耦合,并表明不可分离性改变了原子的几何形状,但不会恶化确定性或有限截面统计鲁棒性界。

英文摘要

We construct an explicit class of non-separable Gabor windows on $L^2(\R^d)$ by applying chirp deformations to tensor-product dual pairs on separable lattices. Starting from one-dimensional dual Gabor frames, we first obtain separable higher-dimensional dual pairs by tensorization. We then transport these systems through the unitary chirp operator $U_C f(x)=e^{πi x^T Cx}f(x)$ and the associated phase-space shear, obtaining Gabor systems on lower block-triangular lattices of the form $ Λ_{A,B,C}=\{(Ak,CAk+B\ell):k,\ell\in\Z^d\}. $ The construction preserves compact support, smoothness, frame bounds, exact duality, canonical duals, and approximate-duality errors. We also quantify chirp-induced coupling through a phase-space covariance defect and show that non-separability changes the geometry of the atoms without deteriorating deterministic or finite-section statistical robustness bounds.

2606.09299 2026-06-09 math.NA cs.NA 新提交

Justification and structure- and asymptotic-preserving discretizations of a hyperbolized Cahn-Hilliard equation

双曲化Cahn-Hilliard方程的正则化及结构保持与渐近保持离散格式

Jan Giesselmann, Fabio Leotta, Hendrik Ranocha, Jochen Schuetz

AI总结 研究双曲化Cahn-Hilliard方程在松弛极限下收敛到原模型的理论,并开发基于迎风求和分部算子的能量稳定半离散格式及IMEX方法,证明其渐近保持性质。

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AI中文摘要

我们研究Dhaouadi、Dumbser和Gavrilyuk (2025, DOI: 10.1098/rspa.2024.0606) 最初提出的Cahn-Hilliard (CH) 方程的双曲近似(“双曲化”),并通过形式渐近展开以及(对于稍作修改的近似)相对能量框架,研究其在松弛极限下向CH模型的收敛性。此外,我们利用空间上的迎风求和分部算子,开发了CH方程及其双曲化的能量稳定半离散格式。随后,我们基于凸-凹分裂,将它们与(加性)隐式-显式(IMEX)Runge-Kutta方法结合。我们证明所得方法是渐近保持的,即在松弛参数极限下收敛到原始CH方程的稳定离散格式。必要参数的选择由基于相对能量框架的先验误差估计指导。

英文摘要

We study a hyperbolic approximation ("hyperbolization") of the Cahn-Hilliard (CH) equation, originally proposed by Dhaouadi, Dumbser, and Gavrilyuk (2025, DOI: 10.1098/rspa.2024.0606) and study its convergence towards the CH model in a relaxation limit both via formal asymptotic expansions and, for a slightly modified approximation, via the relative energy framework. Moreover, we develop energy-stable semidiscretizations of the CH equation and of this hyperbolization using upwind summation-by-parts operators in space. Subsequently, we combine them with (additive) implicit-explicit (IMEX) Runge-Kutta methods based on a convex-concave splitting. We show that the resulting method is asymptotic preserving, i.e., it converges in the limit of the relaxation parameter to a stable discretization of the original CH equation. The choice of the necessary parameters is guided by the a priori error estimate based on the relative energy framework.

2606.09298 2026-06-09 physics.space-ph 新提交

Are the Parker and Focused Transport Equations Equivalent for Galactic Cosmic Ray Modulation?

帕克方程与聚焦输运方程在银河宇宙线调制中是否等价?

J. P. van den Berg, N. E. Engelbrecht, R. D. Strauss

AI总结 通过数值模拟比较无漂移的帕克输运方程和聚焦输运方程,发现帕克方程在低能下高估地球轨道处宇宙线强度约30%,极区约40%,源于其对粒子流和弱俯仰角散射的过度扩散描述。

Comments 22 pages, 6 figures, 3 appendices. To be published in Astronomy & Astrophysics

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AI中文摘要

帕克输运方程(TPE)在过去60年中一直是银河宇宙线(GCR)调制研究的首选方程。相反,聚焦TPE通过建模各向异性分布而非各向同性分布,在比帕克TPE更基础的层面上描述了相同的过程。通常假设帕克TPE适用于模拟GCR,但两种TPE在此背景下尚未相互验证。我们首次在无粒子漂移的情况下比较了这些TPE,以测试它们在相同扩散条件下是否产生相同结果。开发了一个新的太阳极小期质子模型,使用随机微分方程数值求解TPE。通过将聚焦TPE中使用的俯仰角相关扩散系数(DC)归一化为帕克TPE中使用的各向同性DC,使TPE在扩散方面尽可能一致。帕克TPE在低能下高估地球轨道处的GCR强度约30%,在极区高估约40%。这源于粒子流经极区引起的小一阶各向异性。粒子通过从极区流入更容易进入内日球层,那里俯仰角散射通常较弱,磁场缠绕较少。聚焦TPE对于DC的不同俯仰角依赖性也产生几乎相同的结果。帕克TPE中将粒子流和弱俯仰角散射描述为有效平行扩散使其过度扩散。这表明从帕克TPE拟合观测得到的DC可能被低估。此外,仅凭GCR谱和各向异性数据无法区分具有相似平均自由程但不同俯仰角依赖性的散射理论。

英文摘要

The Parker transport equation (TPE) has been the equation of choice for the past 60 years in studies of galactic cosmic ray (GCR) modulation. Conversely, the focused TPE describes the same processes on a more fundamental level than the Parker TPE by modelling an anisotropic distribution rather than an isotropic one. It is usually assumed that the Parker TPE is valid for modelling GCRs, but the two TPEs have not been tested against each other in this context. We conduct a first-of-its-kind comparison of these TPEs without particle drifts to test whether they produce the same results under identical diffusion conditions. A new model for protons during solar minimum conditions is developed to numerically solve the TPEs using stochastic differential equations. The TPEs are designed to be as consistent as possible for diffusion by normalising the pitch-angle-dependent diffusion coefficients (DCs) used in the focused TPE to the isotropic DCs used in the Parker TPE. The Parker TPE overestimates the GCR intensity at Earth's orbit for low energies by ~30%, and by ~40% over the poles. This stems from a small first-order anisotropy caused by particle fluxes over the poles. Particles gain easier access to the inner heliosphere by streaming in over the poles, where pitch-angle scattering is generally weaker, and the magnetic field is typically less wound. The focused TPE also yields nearly identical results for different pitch-angle dependencies of the DCs. The description of particle streaming and weak pitch-angle scattering as effective parallel diffusion in the Parker TPE makes it overly diffusive. This suggests that DCs derived from fitting the Parker TPE to observations are likely underestimated. Furthermore, GCR spectral and anisotropy data alone cannot distinguish between scattering theories with similar mean free paths but different pitch-angle dependencies.

2606.09297 2026-06-09 cond-mat.stat-mech cond-mat.dis-nn nlin.CD 新提交

Control transition in a temporally random classical spin chain

时间随机经典自旋链中的控制转变

Elisha Shmalo, J. H. Pixley, Manas Kulkarni, Sarang Gopalakrishnan, David A. Huse

AI总结 研究经典自旋链模型中受控与混沌动力学之间的相变,通过交替混沌哈密顿动力学和收缩控制映射,发现相变具有混合特征,且与时间随机性下的有向渗流属于同一普适类。

Comments 13 pages, 11 figures

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AI中文摘要

我们从理论上探讨了一个经典自旋链模型中的受控与混沌动力学之间的相变,该模型受到混沌哈密顿动力学和交替的收缩“控制映射”的影响。控制映射将系统驱动向一个目标构型,该构型在混沌动力学下是不稳定不动点。当控制足够强时,目标构型是动力学的全局吸引稳定不动点;对于较弱控制,多体动力学对几乎所有初始状态保持混沌。受控相与混沌相之间的相变具有混合特征:当从混沌相趋近相变时,远离目标构型的自旋比例连续趋于零,并且存在发散的空间和时间关联长度;然而,主导李雅普诺夫指数在相变处不连续,从混沌相的正值跳跃到受控相的负值。我们提出证据表明,该相变与时间随机性存在下的有向渗流属于同一普适类,对于该普适类,我们获得的结果与动态哈里斯判据一致,但未达到边界。

英文摘要

We theoretically explore a phase transition between controlled and chaotic dynamics in a classical spin chain model subject to chaotic Hamiltonian dynamics and a contractive "control map", which alternate in time. The control map drives the system toward a target configuration that is an unstable fixed point under the chaotic dynamics. When the control is strong enough, the target configuration is the globally attracting stable fixed point of the dynamics; for weaker control, the many-body dynamics remains chaotic for almost all initial states. The phase transition between controlled and chaotic phases has a mixed character: As the transition is approached from the chaotic phase, the fraction of the spins that are far from the target configuration goes continuously to zero, and there are diverging spatial and temporal correlation lengths; however, the leading Lyapunov exponent is discontinuous across the transition, jumping from a positive value in the chaotic phase to a negative value in the controlled phase. We present evidence that this transition is in the same universality class as directed percolation in the presence of temporal randomness, a universality class for which we obtain results that are consistent with the dynamical Harris criterion but do not saturate the bound.

2606.09296 2026-06-09 physics.geo-ph astro-ph.EP 新提交

Satellite gravity constraints on inner core viscosity and LLVPs density anomalies

卫星重力对内核粘度和LLVPs密度异常的限制

Yachong An, Hao Ding, Fred D. Richards, Weiping Jiang, Jiancheng Li, Wenbin Shen

AI总结 通过卫星重力观测与地球自转变化联合分析,约束内核粘度约4.6×10^16 Pa·s及LLVPs底部密度异常约+5.5‰。

Comments 53 pages, 14 figures, 1 table

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AI中文摘要

约束地球深内部的物理性质,特别是固态内核的粘度和大型低速省(LLVPs)的密度结构,仍然是地球物理学中的一个重大挑战。在这里,我们开发了一个统一的动力学框架,将地幔-内核引力耦合(MICG)与流体外核中的扭转振荡相结合,并表明它们的相互作用可以产生一个独特且可测试的大地测量信号。在此预测的指导下,我们分析了卫星重力观测数据以及地表质量变化的独立校正。我们在Stokes系数Delta S22中识别出一个稳健的约6年信号,而在Delta C22中未检测到相应的平稳信号。在日长变化(Delta LOD)中独立检测到具有相同周期的信号,并且这两个信号表现出近乎反相的关系。在此提出的框架内解释这一耦合信号,使我们能够将内核粘度约束为约4.6(±1.8)×10^16 Pa·s,并将内核边界的赤道起伏约束为半轴差约200±70米。反演进一步表明,LLVPs底部的平均密度异常为+5.5(±0.6)‰。这些结果表明,卫星重力测量为地球深部动力学和地球深内部物理性质提供了一个直接的观测窗口。

英文摘要

Constraining the physical properties of Earth's deep interior, particularly the viscosity of the solid inner core and the density structure of large low-velocity provinces (LLVPs), remains a major challenge in geophysics. Here we develop a unified dynamical framework that combines mantle-inner core gravitational coupling (MICG) with torsional oscillations in the fluid outer core and show that their interaction can produce a distinct and testable geodetic signature. Guided by this prediction, we analyze satellite gravity observations together with independent corrections for surface mass variability. We identify a robust approximately 6-year signal in the Stokes coefficient Delta S22, while no corresponding stationary signal is detected in Delta C22. A signal with the same periodicity is independently detected in length-of-day variations (Delta LOD), and the two signals exhibit a near anti-phase relationship. Interpreting this coupled signature within the proposed framework allows us to constrain the inner core viscosity to approximately 4.6 (+/- 1.8) x 10^16 Pa s and the equatorial relief of the inner core boundary to a semi-axis difference of about 200 +/- 70 m. The inversion further indicates mean density anomalies of +5.5 (+/- 0.6) per mil at the base of LLVPs. These results indicate that satellite gravimetry provides a direct observational window into deep-Earth dynamics and the physical properties of Earth's deep interior.

2606.09291 2026-06-09 math.OC cs.NA math.NA 新提交

Multilevel Stochastic Gradient Descent for Risk-Averse PDE-Constrained Optimization

风险规避 PDE 约束优化的多级随机梯度下降

Niklas Baumgarten, Philipp A. Guth, David Schneiderhan, Tommaso Vanzan

AI总结 提出多级随机梯度下降算法求解风险规避三维PDE约束优化问题,利用自适应多级蒙特卡洛梯度估计,相比标准批处理方法具有更优收敛速度和计算复杂度。

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AI中文摘要

我们介绍了将多级随机梯度下降算法应用于风险规避、三维PDE约束优化问题的最新进展。该算法使用自适应多级蒙特卡洛梯度估计,提供并行可扩展性,并且与标准批处理随机梯度下降方法相比,具有更优的收敛速度和计算复杂度。我们使用三维椭圆扩散问题和大风险规避参数在计算要求高的设置中研究了该方法。

英文摘要

We present recent advances in applying and analyzing multilevel stochastic gradient descent algorithms to risk-averse, three-dimensional PDE-constrained optimization problems. The algorithm uses adaptive multilevel Monte Carlo gradient estimates, provides parallel scalability as well as improved convergence rates and computational complexity compared to standard batched stochastic gradient descent methods. We study the method in computationally demanding settings using three-dimensional elliptic diffusion problems and large risk-aversion parameters.

2606.09288 2026-06-09 nucl-th hep-ex hep-ph 新提交

Global Ab initio Neutrino Mass Limits from Neutrinoless Double-Beta Decay

无中微子双贝塔衰变的全局从头算中微子质量限制

T. Shickele, L. Jokiniemi, A. Belley, J. D. Holt

AI总结 结合最新无中微子双贝塔衰变实验和从头算核理论,在贝叶斯框架下给出马约拉纳中微子质量的全局上限,发现当前实验灵敏度尚未覆盖中微子振荡允许的质量区间,但下一代多同位素联合可覆盖反质量顺序。

Comments 9 pages, 5 figures, accepted for publication in Phys. Rev. D

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AI中文摘要

我们通过结合无中微子双贝塔($0νββ$)衰变搜索的最新结果和从头算核理论,给出了马约拉纳中微子质量的全局限制。这些限制是在贝叶斯框架下推导的,利用了来自一系列$0νββ$衰变实验的似然函数,并结合了从手征有效场论推导并采用介质相似性重正化群多体方法实现的核力和弱力所计算的核矩阵元。与核模型相比,从头算结果表明,当前一代$0νββ$衰变实验可能\textit{尚未}达到探测中微子振荡数据所允许的质量区间所需的灵敏度,而组合界限明显强于单个实验给出的界限。最后,根据下一代搜索的预测灵敏度,我们表明,虽然没有任何一个单独实验完全覆盖反质量顺序,但通过四个关键同位素:$^{76}$Ge、$^{100}$Mo、$^{130}$Te和$^{136}$Xe的联合贡献可以实现这一目标。

英文摘要

We present global limits for Majorana neutrino masses by combining latest results from neutrinoless double-beta ($0νββ$) decay searches and ab initio nuclear theory. Limits are derived in a Bayesian framework utilizing likelihood functions from a suite of $0νββ$-decay experiments in conjunction with nuclear matrix elements calculated from nuclear and electroweak forces derived from chiral effective field theory and implemented in the in-medium similarity renormalization group many-body approach. In contrast to nuclear models, ab initio results indicate that the current generation of $0νββ$-decay experiments have likely \textit{not} yet reached sensitivities required to probe the mass regime allowed by neutrino-oscillation data, where the combined bounds are notably stronger than those given by individual experiments. Finally, from predicted sensitivities of next-generation searches, we show that, while no one individual experiment fully covers the inverted mass ordering, this can be achieved from combined contributions from the four key isotopes: $^{76}$Ge, $^{100}$Mo, $^{130}$Te, and $^{136}$Xe.

2606.09285 2026-06-09 math.FA 新提交

Essential contractibility of Banach algebras

Banach代数的本质可收缩性

Batoul S. Mortazavi-Samarin, Mehdi Rostami, Amir Sahami

AI总结 引入Banach代数的本质可收缩性概念,研究其性质,并证明对称抽象Segal代数的本质可收缩性。

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AI中文摘要

本文引入了Banach代数的一个新概念——本质可收缩性,并研究了它的一些性质。主要结果是考察(对称抽象)Segal代数的本质可收缩性。

英文摘要

In this paper, a new notion, essential contractibility of Banach algebras, is introduced and some of its properties are examined. The main result is to investigate the essential contractibility of (symmetric abstract) Segal algebras.

2606.09284 2026-06-09 astro-ph.GA 新提交

Disentangling chemical evolution histories with phylogenetic trees

用系统发育树解开化学演化历史

Rebeca Canales, Paula Jofré, Claudia Aguilera-Gómez, Payel Das, Robert Yates, Theosamuele Signor, Patricia Tissera, Xia Hua, Robert Foley

AI总结 利用系统发育方法分析化学丰度数据,发现质量负载流出参数η是区分演化分支的关键因素,分支连接方式与生物系统相反。

Comments 15 pages, 13 figures

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AI中文摘要

化学丰度以复杂多样的方式编码了星系演化的化石记录,需要创新方法来重建星系历史。我们研究了使用系统发育方法在解析化学演化模型中的不同演化路径的能力。我们使用flexCE运行了1024个单区化学演化模型。将得到的化学丰度与两个基准模型(mw-fid和dw-fid)的丰度结合,用于确定哪些组合能产生双分支系统发育树,以及这些树如何纯粹地分裂两个输入模型。我们使用随机森林和Shapley分析来预测哪些模型组合能返回良好分离的树,并解释哪些输入参数对此最重要。我们还研究了丰度模式、恒星形成率、质量积累和分支长度。我们发现,flexCE中的质量负载流出参数η对将模型分离到不同分支的影响最大,因为它驱动化学富集速率和总丰度。恒星形成率和质量积累对η有一定影响,但未发现这些量与丰度之间的直接关系。我们还发现,分支通过树中最富金属的尖端连接,这与生物系统中系统发育树的连接方式相反。当存在代际遗传信息时(如星系演化中的化学元素),系统发育树有助于重建历史。分支拓扑可以提供关于不同种群演化变化速率的信息,分支之间的连接也包含它们共享历史的信息。这项工作通过跨学科研究使我们更进一步理解星系演化。

英文摘要

Chemical abundances encode the fossil record of galaxy evolution in a complex and diverse way that requires innovative approaches to reconstruct galactic histories. We investigate the power of using phylogenetic methods to disentangle different evolutionary pathways in analytical chemical evolution models. We ran 1024 one-zone chemical evolution models using flexCE. The resulting chemical abundances are combined with those of two fiducial models, mw-fid and dw-fid, and then used both to determine which combinations produce two-branched phylogenetic trees, as well as how purely these trees split the two input models. We used random forests and Shapley analysis to predict which model combinations return well-separated trees and explain which input parameters are most important for this. We also studied the abundance patterns, as well as star formation rates, mass accumulation, and branch lengths. We found that η, the mass-loading outflow parameter in flexCE, had the largest impact in separating models into separate branches, due to its importance in driving the chemical enrichment rates and total abundances. Star formation rates and mass accumulation had some impact on η, but no direct relation between these quantities and the abundances was found. We also found that branches connected through the most metal rich tips in our trees, which is opposite to how phylogenetic trees connect in biological systems. Phylogenetic trees help to reconstruct histories when there is information that is inherited between generations, which is the case of the chemical elements in galaxy evolution. Branch topologies can provide information about the rates of evolutionary change of the various populations, and the connection between branches also contains information about their shared history. This work brings us a step further understanding galaxy evolution through cross-disciplinary research.

2606.09283 2026-06-09 nlin.AO stat.AP 新提交

Towards personalised intervention: A causal-dynamical framework to determine psychological treatment trajectories

迈向个性化干预:确定心理治疗轨迹的因果动力学框架

Lourens Waldorp, Titus Mürtz, Anita Jansen, Jonas Haslbeck

AI总结 针对心理健康治疗效果不佳的问题,提出一个因果动力学框架,通过构建因果图、估计因果效应并模拟干预策略,为个体患者定制治疗重点。

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AI中文摘要

对于大约一半接受心理健康护理的个体来说,即使治疗符合循证指南,结果也不理想。这些有限的效果可能部分源于心理健康护理中临床决策如何确定治疗重点。通常,治疗策略由诊断分类结合个体化病例概念化来指导。虽然标准,但这种方法可能因患者和治疗师的偏见以及治疗指南基于可能不完全适合个体患者的平均效应等原因而不足。为了解决这些挑战,我们提出了一个新颖的框架,减少临床决策中的偏见,并真正实现为个体患者量身定制治疗重点。该框架包括:(a) 从密集收集的纵向患者数据中构建因果图并估计因果效应,(b) 基于因果关系模拟新的时间序列,以及 (c) 使用这些模拟来确定对个体患者最有效的治疗重点。通过模拟和比较不同的干预策略,并检查估计的个体反应性及其长期有效性,这种方法可能产生有用的见解来指导治疗重点和策略,从而显著改善心理健康护理的治疗结果。

英文摘要

For approximately half of the individuals receiving mental health care, the results are suboptimal, even when treatments align with evidence-based guidelines. These limited effects may partly stem from how clinical decisions on treatment focus are made in mental health care. Typically, treatment strategy is guided by the diagnostic classification combined with the individualized case conceptualization. While standard, this approach may fall short for several reasons such as biases on the part of both the patient and therapist, and treatment guidelines being based on average effects that may not (exactly) suit the individual patient. To address these challenges, we propose a novel framework that reduces biases in clinical decision-making and makes it genuinely possible to tailor treatment focus to the individual patient. This framework involves (a) constructing causal graphs and estimating causal effects from intensively collected, longitudinal patient data, (b) simulating new time series based upon the causal relationships, and (c) using these simulations to identify the most effective treatment focus for the individual patient. By simulating and comparing different intervention strategies and examining both the estimated individual's responsiveness and its long-term effectiveness, this approach may generate useful insights to guide treatment focus and strategy, which can lead to a significant improvement of treatment outcomes in mental health care.