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2603.19875 2026-06-08 cond-mat.mes-hall cond-mat.mtrl-sci 版本更新

Anatomy of the modern theory of orbital magnetism from first-principles: term-by-term analysis in the gauge-covariant formalism

现代轨道磁性理论的解剖:基于第一性原理的项级分析:在规范协变形式中的分析

Hojun Lee, Insu Baek, Mirco Sastges, Yuriy Mokrousov, Hyun-Woo Lee, Dongwook Go

AI总结 本文基于现代理论,通过Berry相分析不同材料中的轨道磁性,探讨了带结构特征的微观性质,并揭示了轨道磁性与化学性质的相互作用。

Comments 36 pages, 12 figures, Accepted version in Phys. Rev. B

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Journal ref
Physical Review B (2026)
AI中文摘要

我们通过所谓的现代理论,基于Berry相,深入分析了轨道磁性,涵盖了过渡金属、sp金属和过渡金属二硫化物等不同材料类别,突出带结构特征的微观性质。我们采用Lopez等人提出的规范协变形式的现代理论,使在任一选择的Wannier函数规范下都能控制计算轨道磁性,并给出总贡献作为规范不变的可测量。这能一致地捕捉到Wannier基函数的异常位置、速度和轨道角动量的贡献,以及哈密顿量的贡献,其总和是规范不变的。对于过渡金属,我们发现原子中心近似捕捉了现代理论给出的大部分总贡献,这归因于d电子的局域性质。然而,5d金属相比3d金属表现出更大的两种方法之间的偏差,因为5d电子比3d电子更非局域化。另一方面,sp金属表现出两种方法之间的强烈偏差,其中sp电子的动能很重要。最后,在1H-MoS2中,我们发现由于价带和导带之间在直接带隙中的相干混合,谷轨道动量远超d电子的原子极限。我们的工作阐明了电子轨道的化学性质和带结构效应的一致相互作用,并突显了Berry相在轨道磁性中的作用。结果表明,轨道电子学在控制原子轨道之外有广阔前景,通过利用Berry相可显著增强轨道磁性。

英文摘要

We present an in-depth analysis of the orbital magnetism by means of the so-called modern theory based on the Berry phase across distinct classes of materials-d transition metals, sp metals, and transition metal dichalcogenides-highlighting the microscopic nature of band structure characteristics. We adopt a gauge-covariant formulation of the modern theory proposed in [Lopez et al. Phys. Rev. B 85, 014435 (2012)], which enables the calculation of orbital magnetism in a controlled manner in any chosen gauge of Wannier functions and gives the total contribution as a gauge-invariant measurable. This captures consistently the contributions due to the anomalous position, velocity, and orbital angular momentum of Wannier basis, as well as the contributions due to Hamiltonian such that their sum is gauge-invariant. For d transition metals, we find that the atom-centered approximation captures the majority of the total contribution given by modern theory, which we attribute to localized nature of d electrons. However, 5d metals tend to exhibit larger deviation between the two methods than 3d metals do, as 5d electrons are more delocalized than 3d electrons. On the other hand, sp metals exhibit a strong deviation between the two methods, where large kinetic energy of sp electrons is important. Finally, in 1H-MoS2, we find that the valley orbital moment far exceeds the atomic limit of d electrons due to coherent hybridization between valence and conduction bands in direct band gaps. Our work elucidates the interplay of the chemical nature of electronic orbitals and the effect of band structures in a consistent manner and highlights the role of Berry phase in orbital magnetism. The results suggest a promising direction of orbitronics beyond controlling atomic orbitals, in which the orbital magnetism can be greatly enhanced by exploiting Berry phase.

2603.22189 2026-06-08 physics.med-ph physics.bio-ph 版本更新

First Standard Quantification of Ultrasound Attenuation in Healthy Periodontal Soft Tissues In Vivo

首次对健康牙周软组织超声衰减的量化研究

Daria Poul, Amanda Rodriguez Betancourt, Ankita Samal, Carole Quesada, Ted Lynch, Cristel Baiu, J. Brian Fowlkes, Hsun-Liang Chan, Oliver D. Kripfgans

AI总结 本文首次量化活体中健康牙周软组织的超声衰减,采用验证标准技术,为牙科定量超声成像奠定基础,揭示了牙龈组织的衰减特性及潜在生物标志物价值。

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AI中文摘要

本文首次对活体中健康牙周软组织的超声衰减进行了量化研究,采用验证标准技术,为牙科定量超声成像奠定了基础。当前牙科临床中诊断牙周疾病如炎症的标准有限,受主观性、定性评估和晚期指示限制。因此,超声成像的应用正逐渐成为非侵入性和定量评估的替代手段,成为一项具有显著潜在生物标志物价值的新研究领域。许多定量超声分析依赖于量化超声衰减系数(UAC),作为干扰因素。在此,我们对一组猪群(N=10)的健康牙周组织(牙龈)进行了高频率(24 MHz)UAC的量化研究。UAC通过频谱差法进行估算。从四个口腔象限中选取五个邻近口腔部位进行成像:前磨牙3-中,前磨牙3-远,前磨牙4-远,第一磨牙1-远,第二磨牙2-远。总共分析了162个口腔部位。这些口腔部位的UAC中位数(1四分位数|3四分位数)分别为1.66(1.25|1.99)、1.37(1.06|1.64)、0.99(0.8|1.25)、1.08(0.89|1.47)和1.28(0.94|1.24)dB/MHz·cm。在前磨牙3-中部位的牙龈衰减均值显著高于其他所有口腔部位,其余部位的均值差异无显著性。在所有非显著性口腔部位中,平均UAC为1.17 dB/MHz·cm,标准差为0.49 dB/MHz·cm。本研究不仅首次揭示了口腔组织的重要声学特性,还为未来开发依赖于准确衰减知识的牙周/牙科健康护理的多种定量超声生物标志物奠定了基础。

英文摘要

This study presents the first quantifications of ultrasound attenuation in oral soft tissues using validated standard techniques and serves as foundational step in advancing quantitative ultrasound (QUS) imaging in dentistry. Current standards of care in clinics for diagnosing periodontal diseases such as inflammation are limited by subjectivity, qualitive assessment, and late-stage indication. As a result, the application of ultrasonography is emerging as a surrogate for non-invasive and quantitative assessments and a relatively new research area with significant potential biomarkers to be explored. Many QUS analyses rely on quantifying ultrasound attenuation coefficient (UAC), as a confounding factor. Here, in a swine cohort (N=10), we characterized the high-frequency (24 MHz) UAC of healthy periodontal tissues (gingiva) in vivo. UAC were estimated using spectral difference method. Five interproximal oral sites were imaged from four oral quadrants: Premolar 3-Mesial, Premolar3-Distal, Premolar4-Distal, Molar1-Distal, and Molar2-Distal. A total of 162 oral sites were analyzed. The respective medians (1st-quartile|3rd-quartile) UACs for these oral sites were 1.66 (1.25|1.99), 1.37 (1.06|1.64), 0.99 (0.8|1.25), 1.08 (0.89|1.47), and 1.28 (0.94|1.24) dB/MHz.cm. The gingival attenuation mean at Premolar3-Mesial was significantly higher than any other oral sites while the rest of them showed non-significance difference in their means. Across all non-significant oral sites, the average UAC was 1.17 dB/MHz.cm with a standard deviation of 0.49 dB/MHz.cm. This work not only characterized an important acoustic property of oral tissues for the first time but also contributes to future development of a number of QUS biomarkers for periodontal/dental healthcare that rely on accurate attenuation knowledge.

2603.21472 2026-06-08 math.RT 版本更新

Holographic operators for the tensor products of the spaces of holomorphic functions on Hermitian symmetric spaces of tube type

张量积的全纯函数空间上的全息算子

Ryosuke Nakahama

AI总结 研究全纯函数空间张量积的分解,构造全息算子作为积分算子,推广Kobayashi-Pevzner的结果。

Comments 39 pages

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AI中文摘要

我们考虑两个全纯函数空间在管型Hermitian对称空间上的张量积。通常这种分解为不可约子表示的直接和。在本文中,我们构造从每个不可约分量到张量积的 intertwining 算子(全息算子)作为积分算子。这推广了Kobayashi--Pevzner(2020)的结果。

英文摘要

We consider a tensor product of two spaces of holomorphic functions on a Hermitian symmetric space of tube type. Then generically this is decomposed into a direct sum of irreducible subrepresentations. In this manuscript, we construct the intertwining operator (holographic operator) from each irreducible summand to the tensor product as an integral operator. This gives a generalization of the result by Kobayashi--Pevzner (2020).

2602.23989 2026-06-08 cond-mat.str-el 版本更新

Triplon-mediated pairing and the superconducting gap structure in bilayer nickelates

三重子介导的配对及双层镍酸盐中超导能隙结构

Huimei Liu, Giniyat Khaliullin

AI总结 研究双层镍酸盐中三重子介导的超导能隙结构,揭示了局域d³z²-r²自旋与dx²-y²导带共存的机制,通过强层间耦合驱动局域自旋进入单态基态,三重子介导配对交互产生反号能隙参数,解释了实验关键特征。

Comments 6 pages, 5 figures. Fig. 5 and its discussion revised, comparison with other works added

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AI中文摘要

我们研究了双层镍酸盐中超导能隙结构,基于导带dx²-y²与局域d³z²-r²自旋共存的模型。强层间耦合将局域自旋驱动至单态基态,其虚单态-三态激发("三重子")介导配对相互作用。该机制产生反号能隙参数,即两带(alpha和beta)的序参数符号相反。计算的隧道光谱自然解释了关键实验特征,包括alpha带尽管态密度较小但能隙较大,以及由非局域Kondo耦合诱导的能隙各向异性。结果支持三重子介导配对为双层镍酸盐中超导性的微观起源。

英文摘要

We investigate the superconducting gap structure in bilayer nickelates within a model in which conduction bands of dx2-y2 symmetry coexist with localized d3z2-r2 spins. Strong interlayer coupling drives the local moments into a singlet ground state, whose virtual singlet-triplet excitations ("triplons") mediate the pairing interaction. This mechanism yields interband s+- pairing, with opposite signs of the order parameter on the two (alpha and beta) bands. The calculated tunneling spectra naturally explain the key experimental features, including a larger gap on the alpha band despite its smaller density of states and a gap anisotropy induced by nonlocal Kondo coupling. The results support triplon-mediated pairing as the microscopic origin of superconductivity in bilayer nickelates.

2603.18670 2026-06-08 cs.NI 版本更新

Masking Intent, Sustaining Equilibrium: Risk-Aware Potential-Game-Based Service Provision in Dynamic Mobile Crowdsensing

掩盖意图,维持平衡:基于风险的潜在游戏的动态移动 crowdsensing 服务提供

Houyi Qi, Minghui Liwang, Kaiwen Tan, Wenyong Wang, Sai Zou, Yiguang Hong, Xianbin Wang, Wei Ni

AI总结 本文提出iParts框架,通过隐私保护和风险意识的两阶段方法,解决动态移动 crowdsensing 中任务完成、预算可行性和传感质量的不确定性问题。

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AI中文摘要

移动 crowdsensing (MCS) 正从基本数据收集发展为动态服务提供,平台必须在不确定的工人可用性下维持任务完成、预算可行性和传感质量。除了原始数据和位置隐私外,工人的长期意图轨迹,如任务选择倾向和参与历史,可以被诚实但好奇的平台利用,从一个或多个分配快照中推断出隐私偏好。工人退出和执行不确定性进一步破坏传感覆盖,而频繁的全局重新优化增加了交互开销和可观察暴露。为了解决这些问题,我们提出了iParts,一个意图保持和风险意识的两阶段服务提供框架。在离线阶段,工人通过个性化本地差分隐私和记忆化的永久随机响应报告扰动的意图向量,抑制基于频率的意图推断,同时保留决策效用。平台随后构建一个冗余意识的质量模型,并在预算、质量风险和意图不匹配约束下进行风险意识的预规划。此离线问题被建模为一个精确的潜在游戏,预期社会福利作为潜在函数,保证在可行改进动态下约束均衡的存在和有限步收敛。在在线阶段,通过有限轮次的临时招募闲置或备用工人修复质量缺陷,实现可行性保持的调整,同时限制暴露。实验表明,iParts在减少冗余和通信开销的同时,提高了福利和任务完成率,优于代表性基准。

英文摘要

Mobile crowdsensing (MCS) is evolving from basic data collection to dynamic service provisioning, where platforms must maintain task completion, budget feasibility, and sensing quality under uncertain worker availability. Beyond raw-data and location privacy, workers' long-term intent traces, such as task-selection tendencies and participation histories, can be exploited by an honest-but-curious platform to infer private preferences from one or multiple allocation snapshots. Worker dropouts and execution uncertainty further destabilize sensing coverage, while frequent global re-optimization increases interaction overhead and observable exposure. To address these issues, we propose \textit{iParts}, an intent-preserving and risk-aware two-stage service provisioning framework for dynamic MCS. In the offline stage, workers report perturbed intent vectors through personalized local differential privacy with memoized permanent randomized response, suppressing frequency-based intent inference while retaining decision utility. The platform then builds a redundancy-aware quality model and performs risk-aware pre-planning under budget, quality-risk, and intent-mismatch constraints. This offline problem is formulated as an exact potential game with expected social welfare as the potential function, guaranteeing constrained equilibrium existence and finite-step convergence under feasible improvement dynamics. In the online stage, quality deficits are repaired through bounded-round temporary recruitment from idle or standby workers, enabling feasibility-preserving adjustment with limited exposure. Experiments show that iParts improves welfare and task completion while reducing redundancy and communication overhead against representative benchmarks.

2602.16899 2026-06-08 cond-mat.str-el 版本更新

Ground State of BaFe2S3 from Lattice and Spin Dynamics

BaFe₂S₃的基态:晶格与自旋动力学

Y. Oubaid, S. Deng, NS. Dhami, M. Verseils, D. Bounoua, A. Forget, D. Colson, P. Foury-Leylekian, M. B. Lepetit, V. Balédent

AI总结 研究BaFe₂S₃中晶格对称性、声子与磁性相互作用,揭示低温下晶格对称性降低及磁有序机制,发现磁动态关联驱动结构不稳定。

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AI中文摘要

我们通过极化同步辐射红外光谱、杂化功能密度泛函理论计算和非弹性中子散射,研究了准一维梯状化合物BaFe₂S₃中晶格对称性、声子和磁性之间的相互作用。晶格动力学分析表明,低温下晶体对称性低于先前提出,与P1空间群一致。几种红外活性声子模式在结构转变温度T_S≈125-130 K和奈尔温度T_N≈95 K处表现出显著异常。第一性原理计算显示,受T_S影响的模式主要涉及调节磁交换路径的位移。中子散射显示,在T_N以下,磁序为三维、长程且静态。在T_N和T_S之间,系统表现出三维短程动态磁关联,这些关联在T_S以上消失。因此,结构转变与磁振荡的起始而非静态磁序相关。我们的结果表明,短程动态磁关联足以驱动静态结构不稳定,提供了一种磁驱动机制,类似于铁基122家族,但在此准一维Mott系统中实现。这些发现突显了铁基超导体中磁弹性耦合在非它inerant区域的重要性。

英文摘要

We investigate the interplay between lattice symmetry, phonons, and magnetism in the quasi-one-dimensional ladder compound BaFe$_2$S$_3$ by combining polarized synchrotron infrared spectroscopy, hybrid-functional density functional theory calculations, and inelastic neutron scattering. Lattice-dynamics analysis reveals that the crystal symmetry is lower than previously proposed and is consistent with a $P1$ space group at low temperature. Several infrared-active phonon modes exhibit pronounced anomalies at both the structural transition temperature $T_S \approx 125$--$130$~K and the Néel temperature $T_N \approx 95$~K. First-principles calculations show that the modes affected at $T_S$ predominantly involve displacements that modulate magnetic exchange pathways. Neutron scattering demonstrates that below $T_N$ the magnetic order is three-dimensional, long-ranged, and static. Between $T_N$ and $T_S$, the system displays three-dimensional short-range dynamic magnetic correlations, which disappear above $T_S$. The structural transition thus coincides with the onset of magnetic fluctuations rather than with static magnetic order. Our results indicate that short-range, dynamical magnetic correlations are sufficient to drive a static structural instability, providing a magnetically driven mechanism reminiscent of the iron-pnictide 122 family, yet realized here in a quasi-one-dimensional Mott system. These findings highlight the central role of magnetoelastic coupling in iron-based superconductors beyond the itinerant regime.

2511.04080 2026-06-08 cs.IR 版本更新

Caption Injection for Optimization in Generative Search Engine

生成搜索引擎中的标题注入用于优化

Xiaolu Chen, Jie Bao, Haojie Wu, Zhen Chen, Yong Liao

AI总结 本文提出Caption Injection,一种多模态G-SEO方法,通过提取图像标题并注入文本内容,提升生成搜索中的主观可见性,实验表明其在G-EVAL指标下优于文本-only基线。

Comments 24 pages, 4 figures, ECML PKDD 2026 Accepted

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AI中文摘要

生成搜索引擎(GSE)利用检索增强生成(RAG)技术与大语言模型(LLM)整合多源信息,为用户提供准确全面的响应。不同于传统搜索引擎以排名列表呈现结果,GSE将用户注意力从顺序浏览转向内容驱动的主观感知,不仅推动了信息检索范式变革,还突显了增强生成搜索中内容主观可见性的重要性。在此背景下,生成搜索引擎优化(G-SEO)方法成为新的研究重点。随着多模态检索增强生成(MRAG)技术的迅速发展,GSE如今能够高效整合文本、图像、音频和视频,生成更丰富的响应以满足复杂的信息需求。然而,现有G-SEO方法仍局限于文本优化,未能充分挖掘多模态数据。为解决这一差距,我们提出了Caption Injection,即首个多模态G-SEO方法,该方法从图像中提取标题并将其注入文本内容,整合视觉语义以增强生成搜索中的主观可见性。我们系统地在MRAMG基准(用于MRAG)上评估Caption Injection,分别在单模态和多模态设置下进行实验。实验结果表明,Caption Injection在G-EVAL指标下显著优于文本-only G-SEO基线,有效提升了用户感知内容的主观可见性,并展示了多模态信息在G-SEO中的实际效益。本工作的源代码在https://github.com/GrayChan04/Caption-Injection上公开。

英文摘要

Generative Search Engine (GSE) leverages the Retrieval-Augmented Generation (RAG) technique and the Large Language Model (LLM) to integrate multi-source information and provide users with accurate and comprehensive responses. Unlike traditional search engines that present results in ranked lists, GSE shifts users' attention from sequential browsing to content-driven subjective perception, not only driving a paradigm shift in information retrieval but also highlighting the importance of enhancing the subjective visibility of content in generative search. In this context, Generative Search Engine Optimization (G-SEO) methods have emerged as a new research focus. With the rapid advancement of Multimodal Retrieval-Augmented Generation (MRAG) techniques, GSE can now efficiently integrate text, images, audio, and video, producing richer responses that better satisfy complex information needs. Existing G-SEO methods, however, remain limited to text-based optimization and fail to fully exploit multimodal data. To address this gap, we propose Caption Injection, the first multimodal G-SEO approach, which extracts captions from images and injects them into textual content, integrating visual semantics to enhance the subjective visibility in generative search. We systematically evaluate Caption Injection on MRAMG, a benchmark for MRAG, under both unimodal and multimodal settings. Experimental results show that Caption Injection significantly outperforms text-only G-SEO baselines under the G-EVAL metric, effectively improving the subjective visibility of content perceived by users, and demonstrating the practical benefits of multimodal information in G-SEO. The source code for this work is openly available at https://github.com/GrayChan04/Caption-Injection.

2603.17003 2026-06-08 math.OC cs.SY eess.SY 版本更新

Constricting Tubes for Prescribed-Time Safe Control

为指定时间安全控制设计的约束管

Darshan Gadginmath, Ahmed Allibhoy, Fabio Pasqualetti

AI总结 本文提出了一种约束控制屏障函数框架,用于具有输入约束的控制仿射系统指定时间控制。通过构造一个随时间变化的安全管,从包含初始条件的放松集缩小到目标集,确保在用户指定的截止时间内恢复。框架通过单个仿射约束每时间步,实现可扩展性。

Comments 8 pages, 6 figures

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AI中文摘要

我们提出了一种约束控制屏障函数(CBF)框架,用于具有输入约束的控制仿射系统的指定时间控制。给定一个系统初始状态在目标安全集外,我们构造一个随时间变化的安全管,从包含初始条件的放松集缩小到目标集,在用户指定的截止时间内。任何使该管前向不变的控制器通过构造保证指定时间恢复。约束计划通过设计是有界的且可调的,与指定时间方法中接近截止时间时控制努力发散不同。可行性在输入约束下归结为对约束速率的一个可验证条件,得出一个闭合形式的最小恢复时间作为控制权限和初始违规的函数。该框架无论状态维度如何,每时间步施加单个仿射约束,适用于网格可达性方法不可行的设置。我们在一个18维多智能体系统上进行了验证,展示了可扩展性和具有有界控制努力的指定时间恢复。

英文摘要

We propose a constricting Control Barrier Function (CBF) framework for prescribed-time control of control-affine systems with input constraints. Given a system starting outside a target safe set, we construct a time-varying safety tube that shrinks from a relaxed set containing the initial condition to the target set at a user-specified deadline. Any controller rendering this tube forward invariant guarantees prescribed-time recovery by construction. The constriction schedule is bounded and tunable by design, in contrast to prescribed-time methods where control effort diverges near the deadline. Feasibilityå under input constraints reduces to a single verifiable condition on the constriction rate, yielding a closed-form minimum recovery time as a function of control authority and initial violation. The framework imposes a single affine constraint per timestep regardless of state dimension, scaling to settings where grid-based reachability methods are intractable. We validate on an 18-dimensional multi-agent system, demonstrating scalability and prescribed-time recovery with bounded control effort.

2410.21070 2026-06-08 math.OC 版本更新

An Adaptive Cubic Regularisation Algorithm Based on Interior-Point Methods for Optimization with General Inequality Constraints

基于内点法的自适应三次正则化算法用于具有通用不等式约束的优化

Yonggang Pei, Jingyi Guo, Detong Zhu

AI总结 本文提出基于内点法的自适应三次正则化算法,用于解决具有通用不等式约束的非线性优化问题,通过构造ARC子问题和边界规则处理线性化约束,并通过复合步法和降维Hessian方法保证全局收敛性。

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AI中文摘要

非线性约束优化在实际应用中具有广泛范围。内点法被认为是解决非线性不等式约束优化问题最强大的算法之一。本文考虑具有通用不等式约束的优化问题,并提出基于内点法的自适应正则化算法(ARCBIP)。为解决障碍问题,我们构造了具有线性化约束的ARC子问题,并采用著名的趋近边界规则,以防止松弛变量过早接近其下界。我们采用复合步法和降维Hessian方法处理线性化约束,其中试步被分解为法向步和切向步。这些步是通过使用趋近边界规则近似求解两个ARC子问题得到的。对法向步和切向步的要求用于确保全局收敛性。为了确定试步是否被接受,我们使用精确惩罚函数作为ARC框架中的目标函数。通过自适应策略更新障碍参数。在温和假设下分析了全局收敛性。报告了初步数值实验和一些比较结果。

英文摘要

Nonlinear constrained optimization has a wide range of practical applications. The interior-point method is considered to be one of the most powerful algorithms for solving nonlinear inequality constrained optimization. In this paper, we consider optimization with general inequality constraints and propose an Adaptive Regularisation algorithm using Cubics Based on Interior-Point methods (ARCBIP). For solving the barrier problem, we construct ARC subproblem with linearized constraints and the well-known fraction to the boundary rule that prevents slack variables from approaching their lower bounds prematurely. We employ a composite-step approach and reduced Hessian methods to deal with linearized constraints, where the trial step is decomposed into a normal step and a tangential step. They are obtained by solving two ARC subproblems approximately with the fraction to the boundary rule. Requirements on normal steps and tangential steps are given to ensure global convergence. To determine whether the trial step is accepted, we use exact penalty function as the merit function in ARC framework. The updating of the barrier parameter is implemented by adaptive strategies. Global convergence is analyzed under mild assumptions. Preliminary numerical experiments and some comparison results are reported.

2603.13813 2026-06-08 astro-ph.HE astro-ph.SR 版本更新

Ultra-compact X-ray Binaries: A Review

超紧致X射线双星:综述

Bo Wang, Dongdong Liu, Yunlang Guo, Hailiang Chen, Wencong Chen, Zhanwen Han

AI总结 本文综述了超紧致X射线双星的形成机制与演化,探讨了其在引力波天文学等领域的应用及研究意义。

Comments 24 pages, 10 figures, accepted for publication in RAA, an invited review

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Journal ref
Res. Astron. Astrophys., Volume 26, 112001 (2026)
AI中文摘要

超紧致X射线双星(UCXBs)是低质量X射线双星(LMXBs)的子类,以极短的轨道周期为特征,通常小于60-80分钟。它们由致密的吸积体和贫氢的供体星组成,吸积体可能是中子星(NS)或黑洞(BH)。UCXBs在天文学的多个领域扮演重要角色,特别是在低频引力波带中作为强连续引力波源,是未来空间引力波观测台如LISA、天琴和太极的关键目标。作为最紧致的双星系统,UCXBs的形成和演化仍存在很大不确定性。本文回顾了四种经典形成通道:白矮星供体通道、氦星供体通道、主序星演化供体通道和吸积诱导坍缩通道,并讨论了这些通道的最新进展,涵盖演化场景、UCXB形成初始参数空间及相关天体。提供了观测UCXBs与理论预期的比较,以及对观测到的黑洞-UCXB候选体的讨论。UCXBs的起源可通过供体星的化学组成及其在质量转移率与X射线亮度与轨道周期图中的位置来约束。本文还探讨了UCXBs在引力波天文学、多信使天文学、双星演化和极端条件下中子星物理等领域的意义。进一步的进展将依赖于多波段观测、更多UCXB样本的发现以及更详细的理论模拟。

英文摘要

Ultra-compact X-ray binaries (UCXBs) are a subclass of low-mass X-ray binaries (LMXBs) characterized by ultra-short orbital periods, typically less than $60-80\,$min. They consist of a compact mass-accretor and a hydrogen-poor mass-donor, in which the mass-accretor could be a neuron star (NS) or even a black hole (BH). UCXBs play an important role in multiple areas of astrophysics. In particular, they are considered strong, continuous gravitational wave (GW) sources in the low-frequency band, making them key targets for future space-based GW observatories such as LISA, TianQin and Taiji. As the most compact binaries, the formation and evolution of UCXBs remain highly uncertain. In this article, we review four classic formation channels: the white dwarf donor channel, the He star donor channel, the evolved main-sequence donor channel, and the accretion-induced collapse channel. We also discuss recent progress in these channels, covering evolutionary scenarios, the initial parameter space for UCXB formation, and associated objects. A comparison between observed UCXBs and theoretical expectations is provided, along with a discussion on the observed BH-UCXB candidates. The origin of UCXBs can be constrained by the chemical composition of mass-donors and their locations in diagrams of mass-transfer rate and X-ray luminosity versus orbital period. We also examine the implications of UCXBs for several astrophysical fields, including GW astronomy, multi-messenger astronomy, binary evolution, and NS physics under extreme conditions. Further progress will depend on multi-wavelength observations, the discovery of more UCXB samples, and more detailed theoretical simulations.

2602.22976 2026-06-08 cs.DS 版本更新

Efficient Parallel Algorithms for Hypergraph Matching

超图匹配的高效并行算法

Henrik Reinstädtler, Christian Schulz, Nodari Sitchinava, Fabian Walliser

AI总结 本文提出高效的并行算法用于超图中的最大匹配计算,通过并行识别局部最大边并加入匹配,分别在CRCW PRAM和CREW PRAM模型中实现不同时间复杂度和工作量的算法,并证明了1/d的近似保证。

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AI中文摘要

本文提出高效的并行算法用于超图中的最大匹配计算,通过并行识别局部最大边并加入匹配,在CRCW PRAM模型中实现$O(\log{\logΔ}\log{m})$时间复杂度和$O(κ\log {m})$工作量的算法,在CREW PRAM模型中实现$O((\logΔ+\log{d})\log{m})$时间复杂度和$O(κ\log {m})$工作量的算法,并证明了1/d的近似保证。

英文摘要

We present efficient parallel algorithms for computing maximal matchings in hypergraphs. Our algorithm finds locally maximal edges in the hypergraph and adds them in parallel to the matching. In the CRCW PRAM models our algorithms achieve $O(\log{\logΔ}\log{m})$ time with $O(κ\log {m})$ work w.h.p. where $m$ is the number of hyperedges, and $κ$ is the sum and $Δ$ is the maximum of all vertex degrees. The CREW PRAM model algorithm has a running time of $O((\logΔ+\log{d})\log{m})$ and requires $O(κ\log {m})$ work w.h.p. It can be implemented work-optimal with $O(κ)$ work in $O((\log{m}+\log{n})\log{m})$ time. We prove a~$1/d$-approximation guarantee for our algorithms. We evaluate our algorithms experimentally by implementing and running the proposed algorithms on the GPU using CUDA and Kokkos. Our experimental evaluation demonstrates the practical efficiency of our approach on real-world hypergraph instances, yielding a speed up of up to 76 times compared to a single-core CPU algorithm.

2603.11890 2026-06-08 cs.SE 版本更新

QUARE: Quality-Aware Requirements Analysis through Multi-Agent Dialectical Negotiation

QUARE:通过多智能体辩证协商进行质量感知的需求分析

Haowei Cheng, Milhan Kim, Foutse Khomh, Teeradaj Racharak, Nobukazu Yoshioka, Naoyasu Ubayashi, Hironori Washizaki

AI总结 QUARE通过多智能体辩证协商解决需求质量分析中的多属性冲突,生成高质量需求规格,提升合规性和可验证性。

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AI中文摘要

自动化需求质量分析仍具挑战性,因需平衡多个冲突的质量属性并保持利益相关者意图。现有大语言模型方法主要依赖任务分解或隐式聚合,限制了系统揭示和解决跨质量冲突的能力。我们提出QUARE(质量感知需求分析),通过项目描述输入,将需求质量分析作为五个质量专业智能体(安全、效率、绿色、可信度、责任)之间的结构化协商过程,由专门的协调器协调。QUARE引入辩证协商协议,通过迭代提案、批评和综合显式暴露跨质量冲突。协商结果通过拓扑验证转换为结构化的KAOS目标模型,并通过检索增强生成(RAG)验证行业标准。我们在五个基准系统(来自MARE和iReDev等RE基准)和一个工业自动驾驶规格上评估QUARE,涵盖安全关键、金融和信息系统领域。结果表明,QUARE达到98.2%的合规覆盖,比基线提高105%;94.9%的语义保持,比最佳基线提高2.3个百分点;具有高可验证性,得分为4.96/5.0,生成比现有多智能体RE框架多25-43%的需求。这些发现表明,当使用能力强的指令微调模型时,架构选择如质量维度分解、显式协商和自动化验证可能比模型规模本身对输出质量贡献更大。

英文摘要

Automating requirements quality analysis remains challenging because multiple, often conflicting quality attributes must be balanced while preserving stakeholder intent. Existing Large-Language-Model (LLM) approaches predominantly rely on task-oriented decomposition or implicit aggregation, limiting their ability to systematically surface and resolve cross-quality conflicts. We present QUARE (QUality-Aware REquirements Analysis), a multi-agent framework that takes a project description as input and formulates requirements quality analysis as structured negotiation among five quality-specialized agents: Safety, Efficiency, Green, Trustworthiness, and Responsibility, coordinated by a dedicated orchestrator. QUARE introduces a dialectical negotiation protocol that explicitly exposes inter-quality conflicts and resolves them through iterative proposal, critique, and synthesis. Negotiated outcomes are transformed into structurally sound KAOS goal models via topology validation and verified against industry standards through retrieval-augmented generation (RAG). We evaluate QUARE on five benchmark systems drawn from established RE benchmarks, MARE and iReDev, and an industrial autonomous-driving specification, spanning safety-critical, financial, and information-system domains. Results show that QUARE achieves 98.2% compliance coverage, a 105% improvement over both baselines; 94.9% semantic preservation, a 2.3 percentage-point improvement over the best baseline; and high verifiability, with a score of 4.96 out of 5.0, while generating 25-43% more requirements than existing multi-agent RE frameworks. These findings suggest that, when using capable instruction-tuned models, architectural choices such as quality-dimension decomposition, explicit negotiation, and automated verification may contribute more to output quality than model scale alone.

2603.11496 2026-06-08 cond-mat.mtrl-sci 版本更新

Valley-dependent electron-phonon scattering in thermoelectric semimetal Ta$_2$PdSe$_6$

Ta$_2$PdSe$_6$中谷依赖的电子-声子散射

Masayuki Ochi, Hitoshi Mori, Akitoshi Nakano

AI总结 研究揭示Ta$_2$PdSe$_6$中电子-声子散射的谷依赖性,发现谷间散射导致费米能级附近电子自能虚部突变,而空穴口袋载流子自能虚部变化较缓。

Comments 9 pages, 9 figures

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Journal ref
Phys. Rev. B 113, 245112 (2026)
AI中文摘要

准一维过渡金属硫化物Ta$_2$PdSe$_6$因其载流子寿命中的强电子-空穴不对称性而成为有前途的热电半导体。然而,这种强不对称性的微观起源仍不清楚。本研究理论上探讨了Ta$_2$PdSe$_6$中的电子-声子散射。存在主要由PdSe$_4$链原子位移构成的软声子模式。该软模式强烈耦合于Γ点处的最高价带,该带略低于费米能级,导致强电子-声子散射。电子口袋底部与该带的能量重叠也遭受强谷间散射,使得电子自能虚部在费米能级附近出现急剧变化。另一方面,空穴口袋载流子的自能虚部表现出中等的能量依赖性。因此,我们发现电子-声子散射在谷依赖性方面是强烈的。我们的发现将有助于理解Ta$_2$PdSe$_6$中观察到的独特输运特性。

英文摘要

Quasi-one-dimensional transition-metal chalcogenide Ta$_2$PdSe$_6$ is a promising thermoelectric semimetal due to the strong electron-hole asymmetry in the carrier lifetime. However, the microscopic origin of such a strong asymmetry remains unclear. In this study, we theoretically investigate electron-phonon scattering in Ta$_2$PdSe$_6$. There is a soft phonon mode mainly consisting of atomic displacements in PdSe$_4$ chains. This soft mode is strongly coupled with the highest valence band at the $Γ$ point, which lies slightly below the Fermi energy, and causes strong electron-phonon scattering. The bottom of the electron pocket energetically overlapped with that band also suffers from strong intervalley scattering, by which the imaginary part of the electron self-energy exhibits a sharp change near the Fermi level. On the other hand, the imaginary part of the self-energy for carriers in the hole pocket shows a moderate energy dependence. Thus, we find that electron-phonon scattering is strongly valley-dependent. Our finding will help us to understand the distinctive transport properties observed in Ta$_2$PdSe$_6$.

2603.10258 2026-06-08 cs.SI 版本更新

Two-Path Operators, Triadic Decompositions, and Majorized Quotients for Ego-Centered Network Compression

双路径算子、三元分解与被支配的商化 quotient 用于自中心网络压缩

Moses Boudourides

AI总结 本文提出双路径算子和三元分解方法,用于压缩以自我为中心的网络,通过商化 quotient 构造和遍历节点的选择,建立双路径转移定理。

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AI中文摘要

双路径(楔形)是聚类、三元闭合、冗余和中介的底层组合对象。受双路径形式化启发,我们发展了算子观点,其中楔形出现诱导一个标准的『双步』矩阵和一个独特的分解,分为边支持(三元)部分和非边支持(开放)部分。随后研究了商化/收缩构造,用于压缩一组支配自我网络以及选定的『遍历』节点,并在收缩下证明了双路径转移定理,建立了一个具有显式非负误差项的不等式和基于楔形公平分解的等价条件。最后,通过十种基准图及其自我遍历收缩使用表格驱动诊断来展示理论。

英文摘要

Two-paths (wedges) are the elementary combinatorial objects behind clustering, triadic closure, redundancy, and brokerage. Motivated by a two-path formalism that links Burt's structural holes to node-centered ego networks, we develop an operator viewpoint in which wedge incidence induces a canonical ``two-walk'' matrix and a unique decomposition into an edge--supported (triadic) part and a nonedge-supported (open) part. We then study quotient/contraction constructions designed to compress collections of dominating ego networks together with selected ``traversing'' nodes, and we prove a two--walk transfer theorem under contraction, establishing an inequality with an explicit nonnegative error term and an equality characterization in terms of a wedge--equitable partition. Finally, we illustrate the theory on ten benchmark graphs and their ego-traversing contractions using table-driven diagnostics.

2512.16935 2026-06-08 physics.gen-ph 版本更新

Exact solution of the two-dimensional (2D) Ising model at an external magnetic field

二维伊辛模型在外部磁场下的精确解

Zhidong Zhang

AI总结 本文通过修改的克利福德代数方法推导出二维伊辛模型在外部磁场下的精确解,探讨了非局域效应及拓扑结构,修正了三维伊辛模型的方法以适应二维情况,并分析了磁场对磁化过程的影响。

Comments 34 pages, 7 figures, Section 3 and figure 6 are added

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AI中文摘要

二维(2D)伊辛模型在外部磁场下的精确解通过修改的克利福德代数方法推导得出。首先,分析了转移矩阵的三种表示形式,即克利福德代数表示、转移张量表示和示意表示,以检验该多体相互作用系统中的非局域效应。确保该系统存在非平凡的拓扑结构,其拓扑结构类似于但不同于零磁场下三维(3D)伊辛模型的拓扑结构。因此,为解决二维伊辛模型在磁场下的解析解而修改了用于三维伊辛模型的方法。此外,应用了一个额外的旋转,作为拓扑洛伦兹变换,以处理系统中的拓扑问题。旋转角度由杨- Baxter关系和随后的旋转角度平均确定,以处理线性变化的拓扑作用。应用磁场会增加磁化率,将临界点移至更高的温度。在临界点温度以上,磁化率保持为零,直到达到临界磁场,此时磁化率会突然跃升,表现为一级磁化过程。所获得的配分函数和磁化率有助于理解物理性质,特别是二维磁性材料的磁化过程。

英文摘要

The exact solution of the two-dimensional (2D) Ising model at an external magnetic field is derived by a modified Clifford algebraic approach. At first, the transfer matrices are analyzed in three representations, i.e., Clifford algebraic representation, transfer tensor representation and schematic representation, to inspect nonlocal effects in this many-body interacting system. It is ensured that nontrivial topological structures exist in this system, which is analogous to (but different with) those in the three-dimensional (3D) Ising model at zero magnetic field. Therefore, the approaches developed for the 3D Ising models are modified to be appropriable for solving analytically the solution of the 2D Ising model at a magnetic field. An additional rotation, serving as a topological Lorentz transformation, is applied for dealing with the topological problems in the present system. The rotation angle for the transformation is determined by Yang-Baxter relations and a subsequent average of rotation angles treating the linear change of the topological actions. Application of a magnetic field increases the magnetization, shifting the critical point to higher temperatures. At the temperature above the critical point, the magnetization keeps zero until a critical field at which it jumps rapidly as a first-order magnetization process. The partition function and the magnetization obtained are helpful for understanding the physical properties, in particular, the magnetization processes of the 2D magnetic materials.

2603.08779 2026-06-08 hep-th 版本更新

A domain wall bound on anti-de Sitter vacua

反德西特真空的领域墙界限

Niccolò Cribiori, Antonia Paraskevopoulou, Thomas Van Riet

AI总结 研究通过变化的领域墙插值反德西特流形真空,推导出反德西特半径上限,从而实现引力子质量下限,验证了引力子猜想和反德西特距离猜想。

Comments 38 pages, 2 figures,v2: minor revisions matching version published in SciPost

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Journal ref
SciPost Phys. 20, 157 (2026)
AI中文摘要

我们考虑通过变化的领域墙插值的反德西特流形真空。要求此类领域墙的张力高于有效描述的紫外截止,从而推导出反德西特半径的上限,我们称之为领域墙界限。这转化为引力子质量的下限,从而实现引力子猜想和反德西特距离猜想。我们测试了领域墙界限在几种具有候选尺度层级的例子上的适用性:经典流形真空、赛车轨道模型、LVS和KKLT-like反德西特真空。经典流形真空和LVS被发现与该界限兼容。对于赛车轨道和KKLT-like反德西特真空,该界限对实现大尺度层级提出了非平凡的约束。

英文摘要

We consider anti-de Sitter flux vacua interpolated by flux-changing domain walls. Demanding that the tension of such a domain wall be above the ultraviolet cutoff of the effective description, we derive an upper bound on the anti-de Sitter radius, which we term domain wall bound. It translates into a lower bound on the gravitino mass, thus realizing the gravitino conjecture and the anti-de Sitter distance conjecture of the swampland program. We test the domain wall bound on several examples with a candidate hierarchy of scales: classical flux vacua, racetrack models, LVS and KKLT-like anti-de Sitter vacua. The classical flux vacua and LVS are found to be compatible with the bound. For racetrack and KKLT-like anti-de Sitter vacua, the bound poses a non-trivial constraint on achieving large hierarchies of scales.

2603.07121 2026-06-08 cond-mat.quant-gas 版本更新

Coexistence Regime and Thermal Crystallization in the cavity-mediated extended Bose-Hubbard Model

腔介导扩展玻色-哈伯德模型中的共存区域与热结晶

Wei-Wei Wang, Jin Yang, Barbara Capogrosso-Sansone, Jian-Ping Lv, Chao Zhang

AI总结 研究腔介导扩展玻色-哈伯德模型在单位填充下的有限温行为,发现超流、莫特绝缘体、超流体固体和电荷密度波相,揭示温度对有序态演化的影响,显示热诱导结晶的形成。

Comments Withdraw this submission for minor bugs in simulation codes

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AI中文摘要

通过路径积分-蒙特卡洛方法,我们研究了单位填充下腔介导扩展玻色-哈伯德模型的有限温行为。在零温下,系统支持超流、莫特绝缘体、超流体固体和电荷密度波相,超流与电荷密度波之间存在强一阶相变,具有宽广的共存区域。聚焦于该共存区域,我们探讨主导序随温度的变化。当系统初始处于超流态时,加热会逐渐抑制超流密度并稳定正常流体。进一步升温时,热辅助的晶格序出现并最终熔化为正常流体。相比之下,初始处于电荷密度波配置的模拟显示密度序的平滑热熔化,无超流相干的重现。总体而言,我们的结果表明,在低温下亚稳态持续存在,但最终在高温下消失,热诱导结晶发生。

英文摘要

By means of path integral- Monte Carlo, we study the finite-temperature behavior of the extended Bose-Hubbard model with cavity-mediated long-range interactions at unit filling. At zero temperature, the system supports superfluid, Mott-insulating, supersolid, and charge-density-wave phases, with a strongly first-order transition between superfluid and charge density wave states characterized by a broad coexistence region. Focusing on this coexistence regime, we explore how the dominant order evolves with temperature. When the system is initialized in a superfluid state, the superfluid density is progressively suppressed upon heating, and a normal fluid is stabilized. Upon further increasing the temperature, a thermally assisted emergence of crystalline order occurs which eventually melts into the normal fluid. In contrast, simulations initialized in a charge-density-wave configuration display a smooth thermal melting of density order, with no reemergence of superfluid coherence. Overall, our results show that metastability persists at low temperatures, but ultimately disappears at higher temperatures, where thermally induced crystallization takes place.

2603.05145 2026-06-08 quant-ph 版本更新

Quantum advantages for syndrome-aware noisy logical observable estimation

量子优势在考虑错误综合征的噪声逻辑可观测量估计中的应用

Kento Tsubouchi, Hyukgun Kwon, Liang Jiang, Nobuyuki Yoshioka

AI总结 本文基于量子估计理论,提出一个信息论框架,量化错误综合征在噪声逻辑可观测量估计中的效用,并区分经典和量子协议,证明经典协议中综合征信息最多可将有效逻辑错误率降低两倍,而量子协议中错误率随编码块数指数衰减。

Comments 32 pages, 5 figures

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AI中文摘要

最近在容错量子计算方面的进展表明,利用逻辑层的错误综合征信息可以显著提高性能,包括从噪声态中估计逻辑可观测量。本文基于量子估计理论,发展了一个信息论框架,以量化错误综合征在噪声逻辑可观测量估计中的效用。我们区分了两种操作模式:经典协议,其中逻辑测量基固定,综合征信息仅用于经典后处理;以及量子协议,其中逻辑量子控制可根据观测到的错误综合征进行调整。对于经典综合征-aware协议,我们证明了一个普遍限制:平均而言,综合征信息最多可将有效逻辑错误率降低两倍,这意味着采样开销最多减少平方。相反,一旦允许基于综合征的量子控制,我们证明有效逻辑错误率随编码块数呈指数衰减。这些发现为设计未来主动利用综合征记录而非解码后丢弃的容错架构提供了基本指导。

英文摘要

Recent progress in fault-tolerant quantum computing suggests that leveraging error-syndrome information at the logical layer can substantially improve performance, including the estimation of logical observables from noisy states. In this work, based on quantum estimation theory, we develop an information-theoretic framework to quantify the utility of error syndromes for noisy logical observable estimation. We distinguish two operational regimes of such syndrome-aware protocols: classical protocols, in which the logical measurement basis is fixed and syndrome information is used only in classical post-processing, and quantum protocols, in which the logical quantum control can be tailored to depend on the observed error syndrome. For classical syndrome-aware protocols, we prove a universal limitation: on average, syndrome information can improve the effective logical error rate by at most a factor of two, implying at most a quadratic reduction in sampling overhead. In contrast, once syndrome-conditioned quantum control is permitted, we demonstrate that the effective logical error rate decays exponentially with the number of code blocks. These findings provide fundamental guidance for designing future fault-tolerant architectures that actively exploit syndrome records rather than discarding them after decoding.

2603.04879 2026-06-08 math.AP 版本更新

The Fractional-Logarithmic Laplacian: Potentials, Regularity, and Critical Compact Embeddings

分数-对数拉普拉斯算子:势、正则性及临界紧嵌入

Rui Chen

AI总结 本文研究分数-对数拉普拉斯算子的势理论和正则性,探讨其临界紧嵌入性质,提出新的对数Bessel空间,并讨论其与经典Bessel空间的关系。

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AI中文摘要

我们为分数-对数拉普拉斯算子$(-Δ)^{s+\ln}$及其非齐次形式$(λI-Δ)^{s+\ln}$$(λ>1)开发了势理论和$L^p$正则性结果。这些算子产生经典Riesz和Bessel势的对数类比。对于相关的对数Bessel核$K_{s+\ln}^λ$,我们获得了表示公式和在原点和无穷远处的尖锐点wise渐进行为,包括显式的主要常数。关键成分是一个在测度层面连接齐次和非齐次符号的桥梁。这使得我们能够在方程$(λI-Δ)^{s+\ln}u=f$和$(-Δ)^{s+\ln}u=f$之间转换,并获得全局$L^p$估计、分布解的适定性,以及自然的对数Bessel空间$\mathcal L^p_{s+\ln,λ}$的尺度。我们还讨论了这些空间对$λ$的依赖性,以及它们与经典Bessel空间和Opic和Trebels引入的对数Bessel势空间的关系。作为应用,我们证明了端点嵌入和临界紧性结果。在临界线$n=2sp$上,我们获得具有对数模连续性的嵌入,得到在有界域上的局部紧性和在径向类中的全局紧性。在亚临界情况$n>2sp$下,我们证明在临界Sobolev指数$p^*=\frac{np}{n-2sp}$处的紧性,恢复临界Lebesgue阈值的紧性,这一现象在经典Sobolev和Bessel尺度中不存在。

英文摘要

We develop potential-theoretic and \(L^p\)-regularity results for the fractional--logarithmic Laplacian \((-Δ)^{s+\ln}\) and its inhomogeneous counterpart \((λI-Δ)^{s+\ln}\), \(λ>1\). These operators lead to logarithmic analogues of the classical Riesz and Bessel potentials. For the associated logarithmic Bessel kernel \(K_{s+\ln}^λ\), we obtain representation formulas and sharp pointwise asymptotics at both the origin and infinity, including explicit leading constants. A key ingredient is a measure-level bridge between the homogeneous and inhomogeneous symbols. This allows us to pass between the equations $(λI-Δ)^{s+\ln}u=f$ and $(-Δ)^{s+\ln}u=f,$ and yields global \(L^p\) estimates, well-posedness for distributional solutions, and a natural scale of logarithmic Bessel spaces \(\mathcal L^p_{s+\ln,λ}\). We also discuss the dependence of these spaces on \(λ\), their relation to the classical Bessel spaces and with the logarithmic Bessel potential spaces introduced by Opic and Trebels. As applications, we prove endpoint embeddings and critical compactness results. On the critical line \(n=2sp\), we obtain embeddings with a logarithmic modulus of continuity, local compactness on bounded domains, and global compactness in the radial class. In the subcritical case \(n>2sp\), we prove compactness at the critical Sobolev exponent $p^*=\frac{np}{n-2sp},$ recovering compactness at the borderline Lebesgue threshold, a phenomenon absent from the classical Sobolev and Bessel scales.

2603.04109 2026-06-08 econ.EM stat.ML 版本更新

Testing Full Mediation of Treatment Effects and the Identifiability of Causal Mechanisms

治疗效应的完全中介检验与因果机制的可识别性

Martin Huber, Kevin Kloiber, Lukáš Lafférs

AI总结 提出检验随机分配治疗是否完全通过中介变量影响结果,以及不同中介的因果机制是否可识别,并扩展至非随机治疗情形。

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AI中文摘要

在因果分析中,理解干预或治疗影响结果的因果机制通常是核心关注点。我们提出一个检验,以评估(i) 在协变量条件下随机分配的治疗的因果效应是否完全由观测到的中间结果(称为中介或替代结果)中介,或仅通过这些中间结果运作,以及(ii) 通过不同中介运作的各种因果机制是否在协变量条件下可识别。我们证明,如果完全中介和因果机制的可识别性都成立,那么条件随机治疗在给定中介和协变量的条件下与结果条件独立。此外,我们将框架扩展到非随机分配治疗的情形。我们表明,在这种情况下,完全中介仍然可检验,而因果机制的可识别性不再有保证。我们提出一个双重机器学习框架来实现该检验,该框架可以纳入高维协变量,并在特定正则条件下具有根n一致性和渐近正态性。我们还通过一个模拟研究展示了我们方法良好的有限样本性能,并提供了两个实证应用,重新审视了关于产妇心理健康和社会规范的随机实验。

英文摘要

In causal analysis, understanding the causal mechanisms through which an intervention or treatment affects an outcome is often of central interest. We propose a test to evaluate (i) whether the causal effect of a treatment that is randomly assigned conditional on covariates is fully mediated by, or operates exclusively through, observed intermediate outcomes (referred to as mediators or surrogate outcomes), and (ii) whether the various causal mechanisms operating through different mediators are identifiable conditional on covariates. We demonstrate that if both full mediation and identification of causal mechanisms hold, then the conditionally random treatment is conditionally independent of the outcome given the mediators and covariates. Furthermore, we extend our framework to settings with non-randomly assigned treatments. We show that, in this case, full mediation remains testable, while identification of causal mechanisms is no longer guaranteed. We propose a double machine learning framework for implementing the test that can incorporate high-dimensional covariates and is root-n consistent and asymptotically normal under specific regularity conditions. We also present a simulation study demonstrating good finite-sample performance of our method, along with two empirical applications revisiting randomized experiments on maternal mental health and social norms.

2603.02995 2026-06-08 cs.DB 版本更新

Graph-Native Normalization

图原生规范化

Johannes Schrott, Maxime Jakubowski, Katja Hose

AI总结 本文提出图原生规范化方法,考虑节点、边及其组合的依赖关系,定义图原生范式和图对象函数依赖,通过算法实现图数据的规范化,通过合成和原生图数据集验证方法有效性。

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AI中文摘要

近年来,知识图谱(KGs)特别是以标注属性图(LPGs)形式出现的,在广泛应用中成为关键组件。尽管KGs缺乏严格模式,导致结构问题,产生冗余和不一致,KG质量问题一直未受重视。受关系数据中使用函数依赖的规范化启发,提出利用节点内依赖的方法。然而,现实KGs也暴露涉及边的函数依赖。本文因此提出图原生规范化,考虑节点、边及其组合的依赖。定义图原生范式和图对象函数依赖,提出相应转换算法。通过广泛合成和原生图数据集评估贡献。

英文摘要

In recent years, knowledge graphs (KGs) - in particular in the form of labeled property graphs (LPGs) - have become essential components in a broad range of applications. Although the absence of strict schemas for KGs facilitates structural issues that lead to redundancies and subsequently to inconsistencies and anomalies, the problem of KG quality has so far received only little attention. Inspired by normalization using functional dependencies for relational data, a first approach exploiting dependencies within nodes has been proposed. However, real-world KGs also expose functional dependencies involving edges. In this paper, we therefore propose graph-native normalization, which considers dependencies within nodes, edges, and their combination. We define a range of graph-native normal forms and graph object functional dependencies and propose algorithms for transforming graphs accordingly. We evaluate our contributions using a broad range of synthetic and native graph datasets.

2603.02536 2026-06-08 cs.IT eess.IV math.IT 版本更新

Semantic Forwarding and Codebook-Enhanced Model Division Multiple Access for Satellite-Terrestrial Networks

语义转发与码本增强的模型分频多址接入用于卫星-地面网络

Jinghong Huang, Mengying Sun, Xiaodong Xu, Jianchi Zhu, Zechuan Fang, Jingxuan Zhang, Ruichen Zhang, Chen Dong, Ping Zhang, Dusit Niyato

AI总结 本文提出一种针对卫星-地面网络的语义转发语义通信框架,通过联合语义编码和调制方案及码本分割增强的模型分频多址接入方法,提升语义压缩效率和频谱效率,实现低信噪比下的高效稳健传输。

Comments This version is being withdrawn because the authors need to further reevaluate the attribution of contributions among the authors

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AI中文摘要

卫星-地面通信受到高路径损耗、有限频谱资源和时变信道条件的严重限制,传统比特级传输方案在低信噪比(SNR)条件下效率低下且脆弱。语义通信作为一种有前景的范式,通过优先考虑任务相关信息而非精确比特恢复来解决这些挑战。本文提出了一种针对卫星-地面网络的语义转发基于语义通信(SFSC)框架。具体而言,我们开发了一种向量量化联合语义编码和调制方案,在其中语义编码器和语义码本联合优化以塑造星座符号分布,提高信道适应性和语义压缩效率。为减轻噪声累积和减少机载计算负担,我们引入了卫星语义转发机制,使中继卫星能够在语义层面直接转发信号而无需完整解码和重新编码。此外,我们设计了一种基于特征级线性调制(FiLM)的信道感知语义重建方案,以融合接收到的SNR与语义特征,在动态信道条件下增强鲁棒性。为进一步支持多用户接入,我们进一步提出一种码本分割增强的模型分频多址接入(CS-MDMA)方法以提高频谱效率。仿真结果表明,所提出的SFSC框架在低SNR条件下相比现有基准方案实现了约7.9 dB的峰值信噪比(PSNR)增益,证明了其在卫星-地面网络中稳健和频谱高效语义传输的有效性。

英文摘要

Satellite-terrestrial communications are severely constrained by high path loss, limited spectrum resources, and time-varying channel conditions, rendering conventional bit-level transmission schemes inefficient and fragile, particularly in low signal-to-noise ratio (SNR) regimes. Semantic communication has emerged as a promising paradigm to address these challenges by prioritizing task-relevant information over exact bit recovery. In this paper, we propose a semantic forwarding-based semantic communication (SFSC) framework optimized for satellite-terrestrial networks. Specifically, we develop a vector-quantized joint semantic coding and modulation scheme, in which the semantic encoder and semantic codebook are jointly optimized to shape the constellation symbol distribution, improving channel adaptability and semantic compression efficiency. To mitigate noise accumulation and reduce on-board computational burden, we introduce a satellite semantic forwarding mechanism, enabling relay satellites to forward signals directly at the semantic level without full decoding and re-encoding. Furthermore, we design a channel-aware semantic reconstruction scheme based on feature-wise linear modulation (FiLM) to fuse the received SNR with semantic features, enhancing robustness under dynamic channel conditions. To support multi-user access, we further propose a codebook split-enhanced model division multiple access (CS-MDMA) method to improve spectral efficiency. Simulation results show that the proposed SFSC framework achieves a peak signal-to-noise ratio (PSNR) gain of approximately 7.9 dB over existing benchmarks in the low-SNR regime, demonstrating its effectiveness for robust and spectrum-efficient semantic transmission in satellite-terrestrial networks.

2504.13729 2026-06-08 quant-ph 版本更新

Quantum Fisher Information and the Curvature of Entanglement

量子 Fisher 信息与纠缠曲率

Zain H. Saleem, Anil Shaji, Anjala M Babu, Da-Wei Luo, Quinn Langfitt, Ting Yu, Stephen K. Gray

AI总结 研究量子 Fisher 信息与纠缠曲率之间的关系,分析两体系统中动态生成纠缠与测量耦合强度的关联,展示特定初始条件下 CoE 等于 QFI 的时间点。

Comments 13 pages, 4 figures

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AI中文摘要

我们探讨了量子 Fisher 信息(QFI)与纠缠曲率(CoE)之间的关系,CoE 定义为两体纠缠的负二阶导数相对于两量子比特耦合的导数。两量子比特系统作为最小模型,用于研究 QFI 与动态生成纠缠在测量量为两体或多体耦合强度时的联系。我们详细分析了纯态无损耗情况下的一般结果,并考虑了一种简单的相互作用哈密顿量在单种损耗应用于量子比特的情况。对于用于估计相互作用哈密顿量中耦合常数的两量子比特探测器,我们证明在某些初始条件下,存在某些时间点使得 CoE 等于 QFI。这些时间点可以与视作耦合参数函数的纠缠度的最大值相关联。我们检查了对称对数导数(SLD)本征态的纠缠度的时间演化。使用 SLD 本征态作为基矢的测量是满足量子 Cramer 边界条件的最优测量。我们证明,对于若干初始分离和初始纠缠态家族,当 CoE 等于 QFI 时,SLD 本征态是简单的产物态。

英文摘要

We explore the relationship between quantum Fisher information (QFI) and the negative of the second derivative of concurrence with respect to the coupling between two qubits, referred to as the curvature of entanglement (CoE). The two-qubit system serves as a minimal model to study the connection between QFI and dynamically generated entanglement in scenarios where the measured quantity is a two- or many-body coupling strength. We analyze in detail the pure-state lossless case for which general results can be inferred and we also consider a simple interaction Hamiltonian in the case of one form of loss applied to the qubits. For a two-qubit quantum probe used to estimate the coupling constant appearing in the interaction Hamiltonian we show, for certain initial conditions, that there are times such that CoE = QFI. These times can be associated with the concurrence, viewed as a function of the coupling parameter, being a maximum. We examine the time evolution of the concurrence of the eigenstates of the symmetric logarithmic derivative (SLD). Measurements using the SLD eigenstates as basis are optimal for saturating the quantum Cramer bound. We show that, for several families of initially separable and initially entangled states, the SLD eigenstates are simple product states when CoE = QFI.

2512.13246 2026-06-08 math.NA cs.NA math.ST stat.TH 版本更新

A geometric $q$-analogue of Hamiltonian Monte Carlo

哈密顿蒙特卡洛的几何 $q$-模拟

Xiaomei Yang, Zhiliang Deng

AI总结 提出哈密顿蒙特卡洛的几何 $q$-模拟,通过 $q$-微积分中的 $q$-变形哈密顿系统替代经典哈密顿动力学,构造 Metropolis 校正的 $q$-HMC 算法,并证明其满足细致平衡。数值实验表明,对于正尺度黑箱目标,$q$-HMC 具有优势。

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AI中文摘要

哈密顿蒙特卡洛 (HMC) 通过将哈密顿动力学与 Metropolis 校正相结合,生成高效的马尔可夫转移。本文通过将经典哈密顿动力学替换为来自 $q$-微积分的 $q$-变形哈密顿系统,发展了 HMC 的几何 $q$-模拟。从拉格朗日形式出发,我们推导出相应的 $q$-哈密顿方程,并证明了在 $q$-变形微分学中相关 $q$-辛形式的形式不变性。为了获得可计算的采样器,我们引入了 Jackson 导数实现,并构建了 Metropolis 校正的 $q$-HMC 算法。该提议在 $q\to1$ 时退化为经典 HMC,而当 $q\neq1$ 时,它将普通导数替换为 $q$-Jackson 有限差分。我们建立了细致平衡,确保生成的马尔可夫转移保持目标分布。数值实验检验了所提方法的计算行为。对于正尺度黑箱目标,$q$-Jackson 力具有尺度一致的解释:$s>0$ 的乘法扰动对应于 $y=\log s$ 中的中心有限差分。在此类例子中,$q$-HMC 紧密跟踪对数坐标有限差分 HMC 和精确梯度基准,而原始加法有限差分可能产生大的力和哈密顿误差。这些结果表明,所提出的 $q$-模拟为 HMC 型采样提供了一个有效的框架,对于正和乘法黑箱目标具有明显优势。

英文摘要

Hamiltonian Monte Carlo (HMC) generates efficient Markov transitions by combining Hamiltonian dynamics with a Metropolis correction. This paper develops a geometric \(q\)-analogue of HMC by replacing classical Hamiltonian dynamics with a \(q\)-deformed Hamiltonian system arising from \(q\)-calculus. Starting from a Lagrangian formulation, we derive the corresponding \(q\)-Hamiltonian equations and prove the formal invariance of the associated \(q\)-symplectic form within the \(q\)-deformed differential calculus. To obtain a computable sampler, we introduce a Jackson-derivative realization and construct a Metropolis-corrected \(q\)-HMC algorithm. The proposal reduces to classical HMC as \(q\to1\), while for \(q\neq1\) it replaces ordinary derivatives by \(q\)-Jackson finite differences. We establish detailed balance, which ensures that the resulting Markov transition preserves the target distribution. Numerical experiments examine the computational behavior of the proposed method. For positive-scale black-box targets, the \(q\)-Jackson force has a scale-consistent interpretation: multiplicative perturbations of \(s>0\) correspond to centered finite differences in \(y=\log s\). In such examples, \(q\)-HMC closely tracks log-coordinate finite-difference HMC and the exact-gradient benchmark, whereas raw additive finite differences may produce large force and Hamiltonian errors. These results suggest that the proposed \(q\)-analogue provides a valid HMC-type sampling framework with a visible advantage for positive and multiplicative black-box targets.

2412.10340 2026-06-08 math.NT math.AG 版本更新

Effective bounds for adelic Galois representations attached to elliptic curves over the rationals

有理数域上椭圆曲线所附带的adelic伽罗瓦表示的有效界

Lorenzo Furio

AI总结 本文研究了无复乘的有理数域上椭圆曲线所附带的adelic伽罗瓦表示的像指数,给出了一个明确的上界,并改进了Zywina和Lombardo之前的成果。

Comments 58 pages

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AI中文摘要

给定一个定义在有理数域上的椭圆曲线E,没有复乘,我们提供了adelic表示ρ_E的像指数的一个显式紧界。特别是,如果h_F(E)是E的稳定Faltings高度,我们证明[GL_2(\widehat{\mathbb{Z}}) : Imρ_E]被上界为10^{21}(h_F(E)+40)^{4.42},当h_F(E)趋于无穷时,被上界为h_F(E)^{3+o(1)}。我们还分类了表示ρ_{E,p^n}的可能像,当Imρ_{E,p}包含在非分裂Cartan的正规化子中时。这一结果改进了Zywina和Lombardo之前的成果。

英文摘要

Given an elliptic curve $E$ defined over $\mathbb{Q}$ without complex multiplication, we provide an explicit sharp bound on the index of the image of the adelic representation $ρ_E$. In particular, if $\operatorname{h}_{\mathcal{F}}(E)$ is the stable Faltings height of $E$, we show that $[\operatorname{GL}_2(\widehat{\mathbb{Z}}) : \operatorname{Im}ρ_E]$ is bounded above by $10^{21} (\operatorname{h}_{\mathcal{F}}(E)+40)^{4.42}$, and, for $\operatorname{h}_{\mathcal{F}}(E)$ tending to infinity, by $\operatorname{h}_{\mathcal{F}}(E)^{3+o(1)}$. We also classify the possible (conjecturally non-existent) images of the representations $ρ_{E,p^n}$ whenever $\operatorname{Im}ρ_{E,p}$ is contained in the normaliser of a non-split Cartan. This result improves previous work of Zywina and Lombardo.

2602.22041 2026-06-08 cs.MA cs.CY 版本更新

Using Feasible Action-Space Reduction by Groups to fill Causal Responsibility Gaps in Spatial Interactions

通过群体可行动作空间缩减来填补空间互动中的因果责任空缺

Ashwin George, Vassil Guenov, Arkady Zgonnikov, David A. Abbink, Luciano Cavalcante Siebert

AI总结 本文提出一种群体因果责任度量方法,用于解决个体中心度量在因果过定性情况下失效的问题,通过定义积极影响类型和分层算法来识别因果责任主体,并通过场景模拟展示群体效应的动态变化。

Comments Presented at COINE workshop collocated with AAMAS 2026

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AI中文摘要

随着自动驾驶车辆和移动机器人与人类互动的兴起,空间互动中的责任问题日益成为研究热点。尽管已有针对空间互动的责任度量指标,但它们大多专注于个体代理的责任。针对因果过定性情况(即多个行为体同时导致结果),个体中心的责任度量失效。为此,本文提出一种衡量群体因果责任的指标。为识别导致受影响代理轨迹的积极代理,进一步形式化了积极影响的类型,并提出一种分层算法以系统地识别积极代理。最后,通过基于场景的模拟展示了考虑群体的益处,以及群体效应如何随交互动态和代理间距离的变化而演变。

英文摘要

Heralding the advent of autonomous vehicles and mobile robots that interact with humans, responsibility in spatial interaction is burgeoning as a research topic. Even though metrics of responsibility tailored to spatial interactions have been proposed, they are mostly focused on the responsibility of individual agents. Metrics of causal responsibility focusing on individuals fail in cases of causal overdeterminism - when many actors simultaneously cause an outcome. To fill the gaps in causal responsibility left by individual-focused metrics, we formulate a metric for the causal responsibility of groups. To identify assertive agents that are causally responsible for the trajectory of an affected agent, we further formalise the types of assertive influences and propose a tiering algorithm for systematically identifying assertive agents. Finally, we use scenario-based simulations to illustrate the benefits of considering groups and how the emergence of group effects vary with interaction dynamics and the proximity of agents.

2602.21770 2026-06-08 physics.ao-ph 版本更新

A Generalized Richardson Number Diagnostic for Turbulence in the Free Atmosphere

自由大气中湍流的广义里奇蒙数诊断

Mohamed Foudad, Miguel A. C. Teixeira, Paul D. Williams, Thorsten Kaluza

AI总结 本文提出新的里奇蒙数Ri_new,通过考虑水平和垂直剪切,改进自由大气湍流诊断,实验证明其在多个阈值下表现更优,尤其在水平剪切显著区域。

Comments This article is under review in Journal of the Atmospheric Sciences

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AI中文摘要

本文介绍了一种新的里奇蒙数Ri_new,用于改进自由大气中湍流的诊断。该公式基于湍流动能预算,考虑了垂直风切变和水平切变(变形和散度),并按水平和垂直涡黏度比(K_mh/K_mv)加权。该方法扩展了传统的里奇蒙数Ri_old,仅考虑垂直切变。通过评估ERA5再分析数据中的超过2.47亿个自动湍流报告,发现Ri_new在多种湍流强度阈值下表现优于其他诊断方法,产生更高的AUC值和改进的探测概率。在K_mh/K_mv约为5000时,Ri_new的技能最高。季节性和区域评估表明,Ri_new在涉及垂直和水平切变的湍流生成区域(如美国大陆和夏季)具有最大的附加价值。Ri_new在所有区域和季节中均表现最佳。空间案例研究表明,Ri_new识别了83-98%的观测到的中等或更高强度湍流事件,而Ri_old仅为54-85%。这种显著的检测改进伴随着假警增益较小的增加,证实了Ri_new在湍流易发区域的更物理现实的表示。这些结果表明,将水平风切变纳入里奇蒙数可提供在湍流诊断中物理一致且统计稳健的改进,对研究和操作应用具有相关性。

英文摘要

A new Richardson number formulation, Ri_new, is introduced to improve the diagnosis of turbulence in the stratified free atmosphere. The formulation is derived from the turbulent kinetic energy budget and accounts for both vertical wind shear and horizontal shear (deformation and divergence), weighted by the ratio of horizontal to vertical eddy viscosities (K_mh/K_mv). This extends the classical Richardson number Ri_old, which accounts only for vertical shear. The diagnostics Ri_new , Ri_old ,and the widely used Turbulence Index 1 (TI1), computed from ERA5 reanalysis, are evaluated using more than 247 million automated turbulence reports from commercial aircraft (2017--2024). Across various turbulence intensity thresholds, Ri_new consistently outperforms the other diagnostics, resulting in higher AUC values and improved probability of detection at operationally relevant false-alarm rates. The highest skill is obtained for K_mh/K_mv approximately 5000. Seasonal and regional evaluations indicate that the added value of Ri_new is largest where turbulence generation involves both vertical and horizontal shear, such as over the contiguous United States and during summer. Ri_new remains the best-performing diagnostic in all regions and seasons. Spatial case studies show that Ri_new identifies 83--98% of observed moderate-or-greater turbulence events compared with 54--85% for Ri_old. This substantial improvement in detection comes with a much smaller increase in false alarms, confirming that Ri_new provides a more physically realistic representation of turbulence-prone regions. These results demonstrate that incorporating horizontal wind shear into the Richardson number yields a physically consistent and statistically robust improvement in turbulence diagnostics, with relevance for research and operational applications.

2602.21411 2026-06-08 cs.DC 版本更新

General Convex Agreement with Near-Optimal Communication

通用凸协议与近最优通信

Marc Dufay, Diana Ghinea, Anton Paramonov

AI总结 本文研究了通用凸协议在长消息场景下的通信复杂度,提出确定性同步协议,实现近最优通信,适用于鲁棒学习和传感器融合等聚合任务。

Comments Working paper

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AI中文摘要

Byzantine Agreement (BA) 考虑 $n$ 个参与者中最多 $t$ 个可能恶意的情况,要求诚实参与者在满足有效性条件(所有诚实参与者输入为 $v$ 时输出为 $v$)下达成一致。Convex Agreement (CA) 通过要求输出在诚实参与者输入的凸包内加强 BA。现有协议在一般凸性空间上要求至少 $O(L \cdot n^2)$ 位通信,与 BA 的 $Ω(L \cdot n)$ 下界存在差距。本文研究此差距,提出确定性同步 CA 协议,在长消息场景下实现近最优通信复杂度。当 $L=Ω(n\cdotκ)$($κ$ 为安全参数)时,协议在有限凸性空间中使用 $\mathcal{O}(L\cdot n\log n)$ 位通信,在欧几里得空间 $\mathbb{R}^d$ 中使用 $\mathcal{O}(L\cdot n^{1+o(1)})$ 通信。协议的渐近最优轮复杂度为 $\mathcal{O}(n)$。若已知诚实输入长度的上界 $L$,则可实现接近最优的容错能力 $t < n/(ω+\varepsilon)$(对于任意常数 $\varepsilon>0$,$ω$ 为凸性空间的 Helly 数)。若无此上界,则容错能力为 $t < n/(ω+\varepsilon+1)$。作为应用示例,本文展示了如何利用协议获得并行 BA 实例的高效解决方案。主要技术贡献是利用提取器图实现确定性分配参与者到委员会,以抵御自适应对手。

英文摘要

Byzantine Agreement (BA) considers a setting of $n$ parties out of which up to $t$ can be byzantine (malicious), and requires the honest parties to agree on an input subject to a condition called \emph{validity}: if all honest parties have input $v$, the output agreed upon must be $v$. Convex Agreement (CA) strengthens BA by requiring the output agreed upon to lie in the convex hull of the honest parties' inputs. This validity condition captures aggregation tasks, such as robust learning and sensor fusion, where honest inputs may differ but should still constrain the final decision. Existing protocols for CA over general convexity spaces require at least $O(L \cdot n^2)$ bits of communication for $L$-bit inputs, leaving a gap with BA's $Ω(L \cdot n)$ lower bound. We investigate this gap, and we present deterministic synchronous CA protocols with near-optimal communication complexity in the long-message regime. When $L=Ω(n\cdotκ)$, where $κ$ is a security parameter, our protocols use $\mathcal{O}(L\cdot n\log n)$ bits of communication for finite convexity spaces and $\mathcal{O}(L\cdot n^{1+o(1)})$ communication for Euclidean spaces $\mathbb{R}^d$. Our protocols also have asymptotically optimal round complexity $\mathcal{O}(n)$. If an upper bound $L$ on the honest inputs' length in bits is known in advance, we achieve near-optimal resilience $t<n/(ω+\varepsilon)$ for any constant $\varepsilon>0$, where $ω$ is the Helly number of the convexity space. When no such bound is known, we achieve resilience $t<n/(ω+\varepsilon+1)$. As a sample application, we show how our protocols can be used to obtain efficient solutions for parallel instances of BA. Our main technical contribution is the use of extractor graphs to obtain a deterministic assignment of parties to committees, which is robust against adaptive adversaries.

2602.21132 2026-06-08 stat.ME 版本更新

Robust and Sparse Generalized Linear Models for High-Dimensional Data via Maximum Mean Discrepancy

基于最大均值差异的高维数据鲁棒稀疏广义线性模型

Xiaoning Kang, Lulu Kang

AI总结 针对高维数据中的异常值和重尾噪声,提出基于最大均值差异(MMD)的惩罚广义线性模型,通过ℓ1惩罚和ADMM算法实现鲁棒估计与变量选择,在模拟中优于传统方法。

Comments 22 pages, 5 tables, 2 figures

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AI中文摘要

高维数据集经常受到异常值和重尾噪声的污染,这可能会严重偏倚如Lasso等标准正则化估计量。尽管最大均值差异(MMD)最近被引入作为鲁棒回归的“通用”框架,但其在高维广义线性模型(GLM)中的应用仍未得到充分探索,特别是在变量选择方面。在本文中,我们提出了一种用于GLM中鲁棒估计和特征选择的惩罚MMD框架。我们引入了一个ℓ1惩罚的MMD目标,并开发了两种版本的估计量:一个完整的O(n²)版本和一个计算高效的O(n)近似版本。为了解决由此产生的非凸优化问题,我们采用了一种基于交替方向乘子法(ADMM)结合AdaGrad的算法。通过涉及高斯线性回归和二元逻辑回归的广泛模拟研究,我们证明了所提出的方法与经典惩罚GLM和现有鲁棒基准方法相比具有很强的竞争力。我们的方法在保持估计精度和变量选择之间的平衡方面表现出特别的韧性,特别是在处理高杠杆点和重尾误差分布时,传统方法的性能可能会波动。

英文摘要

High-dimensional datasets are frequently subject to contamination by outliers and heavy-tailed noise, which can severely bias standard regularized estimators like the Lasso. While Maximum Mean Discrepancy (MMD) has recently been introduced as a ``universal'' framework for robust regression, its application to high-dimensional Generalized Linear Models (GLMs) remains largely unexplored, particularly regarding variable selection. In this paper, we propose a penalized MMD framework for robust estimation and feature selection in GLMs. We introduce an $\ell_1$-penalized MMD objective and develop two versions of the estimator: a full $O(n^2)$ version and a computationally efficient $O(n)$ approximation. To solve the resulting non-convex optimization problem, we employ an algorithm based on the Alternating Direction Method of Multipliers (ADMM) combined with AdaGrad. Through extensive simulation studies involving Gaussian linear regression and binary logistic regression, we demonstrate that our proposed methods are highly competitive with classical penalized GLMs and existing robust benchmarks. Our approach shows particular resilience in maintaining a balance between estimation accuracy and variable selection across diverse contamination scenarios, especially in handling high-leverage points and heavy-tailed error distributions where traditional methods may fluctuate in performance.

2512.00711 2026-06-08 cs.IT cs.DC cs.ET cs.IR math.IT 版本更新

Cross-Domain Federated Semantic Communication with Global Representation Alignment and Domain-Aware Aggregation

跨域联邦语义通信与全局表示对齐与领域感知聚合

Loc X. Nguyen, Ji Su Yoon, Huy Q. Le, Yu Qiao, Avi Deb Raha, Eui-Nam Huh, Walid Saad, Yumin Park, Zhu Han, Choong Seon Hong

AI总结 本文提出一种新的联邦学习框架,通过构建全局表示并结合领域感知聚合,解决跨域语义通信中的领域偏移问题,提升图像重建性能。

Comments 13 pages, 7 figures, 6 tables

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AI中文摘要

语义通信可通过利用原始数据背后的意义显著提高无线系统的带宽利用率。然而,通过语义通信取得的进步紧密依赖于深度学习(DL)模型的发展,这些模型需要大量数据进行训练。为了解决DL模型的数据密集型特性,联邦学习(FL)被提出,以分布式方式训练模型,其中服务器将DL模型广播给网络中的客户端,利用其本地数据进行训练。然而,传统FL方法在客户端数据来自不同领域时会遭受灾难性退化。相比之下,本文提出了一种新的FL框架,通过构建全局表示,对齐客户端的局部特征,以保留不同数据域的语义。此外,识别并解决了具有大量样本的客户端域主导问题,然后通过领域感知聚合方法加以解决。本文首次考虑了在图像重建任务中训练语义通信系统时的领域偏移问题。最后,仿真结果表明,所提出的方法在1 dB信噪比下,相对于模型对比联邦学习(MOON)框架在三个领域中的PSNR值上提升了0.5,并且随着信道质量的提高,这一差距继续扩大。

英文摘要

Semantic communication can significantly improve bandwidth utilization in wireless systems by exploiting the meaning behind raw data. However, the advancements achieved through semantic communication are closely dependent on the development of deep learning (DL) models for joint source-channel coding (JSCC) encoder/decoder techniques, which require a large amount of data for training. To address this data-intensive nature of DL models, federated learning (FL) has been proposed to train a model in a distributed manner, where the server broadcasts the DL model to clients in the network for training with their local data. However, the conventional FL approaches suffer from catastrophic degradation when client data are from different domains. In contrast, in this paper, a novel FL framework is proposed to address this domain shift by constructing the global representation, which aligns with the local features of the clients to preserve the semantics of different data domains. In addition, the dominance problem of client domains with a large number of samples is identified and, then, addressed with a domain-aware aggregation approach. This work is the first to consider the domain shift in training the semantic communication system for the image reconstruction task. Finally, simulation results demonstrate that the proposed approach outperforms the model-contrastive FL (MOON) framework by 0.5 for PSNR values under three domains at an SNR of 1 dB, and this gap continues to widen as the channel quality improves.