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2606.02358 2026-06-02 cs.AR

CHIMERA: A Flexible and Scalable 3.1 TOPS/W AI-MCU with Transformer Accelerator and 563 Gb/s Shared-L2 Memory Subsystem with QoS Guarantees

CHIMERA:一种灵活可扩展的3.1 TOPS/W AI-MCU,集成Transformer加速器和具有QoS保证的563 Gb/s共享L2内存子系统

Lorenzo Leone, Philip Wiese, Gamze İslamoğlu, Michael Rogenmoser, Davide Rossi, Francesco Conti, Luca Benini

AI总结 本文提出Chimera,一种灵活可扩展的微控制器单元(MCU),通过集成Transformer加速器和共享L2内存子系统,在超低功耗边缘实现实时推理,峰值能效和面积效率分别达3.1 TOPS/W和281 GOPS/mm²。

Comments 4 pages, 8 figures

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AI中文摘要

我们提出Chimera,一种灵活可扩展的微控制器单元(MCU),旨在加速超低功耗边缘(数百mW)快速演进的基于Transformer的模型的实时推理。该芯片采用22 nm FDX技术实现,集成了一个紧密耦合在计算集群中的Transformer加速器,该集群包含九个通用RV32IMA核心。通过新颖的L2内存岛子系统,可扩展性延伸到内存层次结构,该子系统支持跨多个集群的数据共享,同时提供563 Gb/s的总带宽。L2子系统为延迟关键型流量提供服务质量保证,实现高达16倍的延迟降低。Chimera实现了3.1 TOPS/W和281 GOPS/mm²的峰值能效和面积效率,与最先进(SoA)SoC相比,能效提高1.37倍,面积效率提高高达100倍。与SoA独立加速器相比,Chimera实现了相当的能效和高达1.8倍的面积效率提升。

英文摘要

We present Chimera, a flexible and scalable Microcontroller Unit (MCU) designed to accelerate real-time inference of rapidly evolving transformer-based models at the ultra-low-power edge (hundred of mW). The chip, implemented in 22 nm FDX technology, integrates a transformer accelerator tightly coupled within a compute cluster featuring nine general-purpose RV32IMA cores. Scalability extends to the memory hierarchy through a novel L2 memory island subsystem, which enables data sharing across multiple clusters while delivering 563 Gb/s aggregate bandwidth. The L2 subsystem enforces quality-of-service guarantees for latency-critical traffic, achieving up to 16x latency reduction. Chimera achieves peak energy and area efficiencies of 3.1 TOPS/W and 281 GOPS/mm2, demonstrating 1.37x higher energy efficiency and up to 100x higher area efficiency compared to State of the Art (SoA) SoCs. Compared to SoA standalone accelerators, Chimera achieves comparable energy efficiency and up to 1.8x higher area efficiency.

2606.02354 2026-06-02 cond-mat.mtrl-sci physics.optics

Layer-Resolved Nonlinear Optics in Finite-Thickness Two-Dimensional Systems

有限厚度二维系统中的层分辨非线性光学

Liangting Ye, Chengzhi Wu, Zeyu Jiang, Bing Huang

AI总结 针对有限厚度范德华多层膜中非线性光学响应的体材料框架失效问题,建立了基于对称性的分类框架,揭示了层分辨的皮肤、弱皮肤和隐藏效应,并通过第一性原理计算验证了堆叠序对响应空间模式和幅度的显著调控。

Comments 9 pages, 5 figures

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AI中文摘要

二维量子约束系统中的非线性光学(NLO)响应通常基于体材料框架作为宏观空间平均来描述。在与纳米器件直接相关的有限厚度范德华多层膜中,这一图像严重失效。这里,我们建立了一个通用的基于对称性的框架,用于分类多层膜中的二阶NLO响应。我们揭示了层分辨的组织结构,分为皮肤效应、弱皮肤效应和隐藏效应,这些效应受局部对称性和堆叠顺序控制。对非磁性和自旋极化系统的第一性原理计算证实了我们的预测,表明仅堆叠就足以显著重塑NLO响应的空间模式和幅度,这一现象无法用标准体材料理论解释。我们的结果确立了堆叠几何作为工程化层状材料中表面选择性NLO响应的有效旋钮。

英文摘要

Nonlinear optical (NLO) responses in two-dimensional quantum-confined systems are typically described within bulk-based frameworks as macroscopic spatial averages. In finite-thickness van der Waals multilayers directly relevant to nanoscale devices, this picture substantially breaks down. Here, we establish a general symmetry-based framework for classifying second-order NLO responses in multilayers. We reveal a layer-resolved organization into skin, weak-skin, and hidden effects governed by local symmetry and stacking order. First-principles calculations for both nonmagnetic and spin-polarized systems confirm our predictions, demonstrating that stacking alone suffices to dramatically reshape both the spatial pattern and magnitude of the NLO response, a phenomenon not explainable within standard bulk theory. Our results establish stacking geometry as an effective knob for engineering surface-selective NLO responses in layered materials.

2606.02353 2026-06-02 astro-ph.GA

Revisiting ram pressure stripping in Wolf-Lundmark-Melotte: No evidence for stripped HI with LGLBS

重新审视Wolf-Lundmark-Melotte中的冲压剥离:LGLBS未发现剥离的HI证据

Daniel R. Rybarczyk, Eric W. Koch, Fabian Caballero Vargas, Snezana Stanimirovic, Nickolas M. Pingel, Julianne J. Dalcanton, Adam K. Leroy, Erik W. Rosolowsky, Michael P. Busch, Chang-Goo Kim, Adam Smercina, Elizabeth Tarantino, Vicente Villanueva, Alberto D. Bolatto, Thomas G. Williams

AI总结 通过分析LGLBS的HI 21厘米观测数据,发现WLM矮星系不存在之前MeerKAT-16所报告的冲压剥离气体,并指出该探测可能源于未校正的观测缺陷。

Comments Accepted for publication to AJ; 6 pages, 4 figures

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AI中文摘要

我们利用本地群L波段巡天(LGLBS)对本地群矮星系Wolf-Lundmark-Melotte(WLM)的HI 21厘米观测数据,寻找冲压剥离的证据。尽管先前MeerKAT-16对WLM的观测显示出具有冲压剥离几何特征的星系外原子气体发射,但我们的观测未发现这种剥离气体的证据。我们证明我们的观测对声称的探测是灵敏的,并表明MeerKAT数据中未校正的观测缺陷导致了看似星系外的发射。缺乏星系外发射消除了对该区域星系际介质密度异常高值的需求。

英文摘要

We analyze HI 21-cm observations of the Local Group dwarf galaxy Wolf-Lundmark-Melotte (WLM) from the Local Group L-Band Survey to search for evidence of ram pressure stripping. While previous MeerKAT-16 observations of WLM showed evidence for off-galaxy atomic gas emission with a geometry suggestive of ram pressure stripping, our observations find no evidence for this stripped gas. We demonstrate that our observations would be sensitive to the claimed detections and suggest that an uncorrected observational flaw with the MeerKAT data led to the apparent off-galaxy emission. The lack of off-galaxy emission obviates the need for uncharacteristically high values of the density of the intergalactic medium in this region.

2606.02349 2026-06-02 physics.plasm-ph

Resistive wall mode induced disruptions in an advanced tokamak

先进托卡马克中的电阻壁模引发的破裂

Sui Wan, Ping Zhu

AI总结 本文利用NIMROD代码对CFETR基线稳态平衡进行非线性三维电阻MHD模拟,研究了电阻壁模(RWM)引发的破裂过程,揭示了RWM驱动磁面随机化、热猝灭和电流猝灭的完整物理图像。

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AI中文摘要

电阻壁模是无壁$β_N$极限以上托卡马克破裂的主要原因之一。本文利用NIMROD代码对CFETR基线稳态平衡中RWM引发的破裂进行了非线性三维电阻MHD模拟。线性计算确认了$n=1$ RWM不稳定性的主导存在,其增长率对壁响应高度敏感,并在高$S$极限下对等离子体电阻的依赖性变弱,同时具有全局外部扭曲模结构。在非线性阶段,RWM驱动快速的磁面随机化和热猝灭,随后是电流猝灭,而电流猝灭因猝灭后Spitzer电阻率的增加而加剧。电流猝灭前的瞬态电流尖峰被证明是极向磁通守恒和内电感快速降低的结果。在电流猝灭后期,闭合磁面从芯部到边缘部分重新形成,向无力态弛豫。环向模耦合、平行热输运、等离子体电阻率和壁电导率强烈调制破裂起始和猝灭动力学。在MHD模型内,这些结果为先进托卡马克配置中RWM驱动的破裂过程提供了完整的视图。

英文摘要

Resistive wall mode is one of the leading causes for tokamak disruptions above the no-wall $β_N$ limit. This paper presents nonlinear three-dimensional resistive MHD simulations of an RWM-induced disruption in a CFETR baseline steady-state equilibrium using the NIMROD code. Linear calculations confirm the dominant presence of the $n=1$ RWM instability, whose growth rate is strongly sensitive to the wall response and becomes weakly dependent on plasma resistivity in the high-$S$ limit, along with a global external-kink-like structure. In the nonlinear phase, the RWM drives rapid flux surface stochastization and a thermal quench, followed by a current quench that is intensified by the post quench increase of Spitzer resistivity. The transient current spike before the current quench is shown to be the outcome of the conservation of poloidal flux and a rapid reduction of internal inductance. During the late current quench stage, closed flux surfaces partially reform from the core region to the edge, relaxing toward the force-free state. Toroidal mode coupling, parallel heat transport, plasma resistivity, and wall conductivity strongly modulate the disruption onset and the quench dynamics. Within the MHD model, these results provide a complete view on the RWM-driven disruption process in advanced tokamak configurations.

2606.02348 2026-06-02 econ.TH cs.CR cs.CY cs.GT

Privacy-preserving Information Sharing in Oligopoly Competitions

寡头竞争中的隐私保护信息共享

Yuxin Liu, M. Amin Rahimian

AI总结 研究在古诺寡头垄断中,通过隐私保护渠道聚合供应商信号的信息共享机制,发现隐私保护需与外部信号结合才能激励披露,并刻画了共享可行区域。

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AI中文摘要

竞争供应商之间的信息共享可以改善不确定性下的决策,但关于竞争对手利用的战略担忧往往阻碍自愿披露。我们研究了在需求不确定的古诺寡头垄断中的信息共享机制,其中平台通过隐私保护渠道聚合供应商的信号,并且可能拥有外生的外部信号。核心挑战是平衡战略安全与信息效用:隐私噪声减少了个体信号的暴露,但也降低了共享信息池的价值。我们首先刻画了一个基线设置,其中对聚合信息的访问取决于参与。在没有外部信号的双公司市场中,无论隐私水平如何,公司都拒绝共享。在n公司市场中,即使没有隐私保护,共享也可能发生,因为不参与的公司失去了对聚合信号的访问。基于此基线,我们表明仅隐私保护不足以激励披露;它必须与足够信息量的外部信号相结合。我们进一步表明,拥有更精确私有信号的公司需要更强的隐私保护。总体而言,我们的结果刻画了共享可行区域,并强调了隐私设计与外部信息环境之间的互补性。

英文摘要

Information sharing among competing suppliers can improve decision-making under uncertainty, yet strategic concerns regarding rival exploitation often deter voluntary disclosure. We study information-sharing mechanisms in a Cournot oligopoly with uncertain demand, where a platform aggregates suppliers' signals through privacy-preserving channels and may also possess an exogenous external signal. The central challenge is to balance strategic safety with informational utility: privacy noise reduces the exposure of individual signals, but also lowers the value of the shared information pool. We first characterize a baseline setting in which access to aggregated information is contingent on participation. In a two-firm market without an external signal, firms refuse to share regardless of the privacy level. In an \(n\)-firm market, sharing may arise even without privacy safeguards because non-participating firms lose access to the aggregated signal. Building on this baseline, we show that privacy protection alone is insufficient to incentivize disclosure; it must be combined with a sufficiently informative external signal. We further show that firms with more accurate private signals require stronger privacy protection. Overall, our results characterize the sharing-feasible region and highlight the complementarity between privacy design and the external information environment.

2606.02347 2026-06-02 cs.CY

Are Algorithm Registers Transparent? Perspectives from Germany

算法注册表透明吗?来自德国的视角

Iman Peljto, Xenia Heilmann, Mattia Cerrato

AI总结 本文通过审计德国现有的两个主要算法注册表(MaKI和Lernende Systeme),评估其透明度,并提出改进建议。

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AI中文摘要

算法注册表是面向公众的数据库,显示公共管理中使用的算法的基本信息。尽管欧洲和全球存在多个此类注册表,但它们提供有意义透明度的能力仍存在争议。在德国,情况尤为分散:没有联邦层面的注册表,但至少有五个州和联邦层面的倡议发布了关于AI系统的信息,其范围和目标各不相同。Alina Lorenz(2025)最近提出的概念性提案概述了德国国家AI透明度注册表的技术和治理要求。我们将该提案重新用作审计工具,从其制定的透明度目标和子目标中提取结构化检查清单。生成的检查清单从德语翻译成英语,并公开发布,以支持从业者审计现有注册表或设计新注册表。我们应用此框架对德国现有的两个主要透明度倡议MaKI和Lernende Systeme进行外部审计,评估它们在多大程度上实现了拟议的目标。我们的审计表明,这些注册表可能需要几项调整才能成为有用的透明度工具。我们进一步提出了注册表透明度水平的可视化,并得出了改进现有德国平台的具体行动项。

英文摘要

Algorithm registers are public-facing databases that display basic information about algorithms employed in public administration. While several such registers exist across Europe and globally, their capacity to deliver meaningful transparency remains contested. In Germany, the landscape is notably fragmented: no federal-level register exists, yet at least five state- and federal-level initiatives publish information about AI systems with varying scopes and objectives. A recent conceptual proposal by Alina Lorenz (2025), outlines technical and governance requirements for a national AI transparency register in Germany. We repurpose this proposal as an audit instrument, extracting structured checklists from the transparency goals and subgoals it formulates. The resulting checklists, translated from German into English, is made publicly available to support practitioners auditing existing registers or designing new ones. We apply this framework to conduct an external audit of the two main existing German transparency initiatives, MaKI and Lernende Systeme, evaluating the extent to which they fulfill the proposed goals. Our audit reveals that several adaptations are likely needed for these registers to serve as an useful transparency instrument. We further propose a visualization of register transparency levels and derive concrete action items for improving existing German platforms.

2606.02344 2026-06-02 cs.CR

I-(OT)^2: A Client-optimal Oblivious Transfer Protocol for IoT Devices

I-(OT)^2: 面向物联网设备的客户端最优的不经意传输协议

Elia Onofri, Andrea Ciccotelli, Roberto Di Pietro

AI总结 针对物联网设备等客户端计算受限场景,提出一种基于二次剩余问题的1-out-of-2不经意传输协议,通过轻量级离线预计算将在线计算负担几乎全部转移给发送方,显著降低接收方计算和通信开销。

Comments 31 pages, 9 Figures, 6 Tables

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AI中文摘要

不经意传输(OT)是一种基本的密码学原语,能够实现隐私保护计算,并构成安全多方计算的核心构建块,同时支持广泛的安全敏感应用:例如私有信息检索、零知识证明和密码认证密钥交换。尽管OT扩展的最新进展显著降低了摊销成本,但它们依赖于随机基础OT的批处理和大量的预计算阶段,这在传输次数较少或通信延迟和客户端计算是关键约束的场景中限制了其实用性。在这种情况下,高效的基础OT协议仍然具有相关性和必要性。在这项工作中,我们提出了$I$-$(OT)^2$,一种基于二次剩余问题的新型基础1-out-of-2 OT协议,专门设计用于最小化接收方的计算和交互。我们的构造在客户端-服务器架构中特别有吸引力,其中接收方运行在低功耗硬件上,例如物联网(IoT)设备。通过轻量级的离线预计算阶段,$I$-$(OT)^2$将在线传输的计算负担几乎完全转移给发送方,同时将在线通信减少到仅交换六条消息和四个摘要。我们提供了协议的详细描述,并附有正式的安全性证明。此外,为了展示$I$-$(OT)^2$的可行性,我们还提供了一个在真实物联网硬件上评估的开源概念验证实现(C语言)。结果令人震惊:对于使用3072位RSA模数的128位安全性,接收方在桌面平台上每次OT的平均在线成本低至2.80微秒,在物联网设备上为39.90微秒,比著名的SimplestOT快10倍以上。

英文摘要

Oblivious Transfer (OT) is a fundamental cryptographic primitive enabling privacy-preserving computation and constitutes a core building block for secure multi-party computation while supporting a wide range of security-sensitive applications: private information retrieval, zero-knowledge proofs, and password-authenticated key exchange, to cite a few. While recent advances in OT extension have significantly reduced amortised costs, their reliance on batches of random base OTs and substantial pre-computation phases limits their practicality in scenarios where the number of transfers is modest or where communication latency and client-side computation are critical constraints. In such settings, efficient base OT protocols remain both relevant and necessary. In this work, we introduce $I$-$(OT)^2$, a novel base 1-out-of-2 OT protocol grounded in the quadratic residuosity problem, specifically designed to minimise receiver-side computation and interaction. Our construction is particularly appealing on client--server architectures in which the receiver operates on low-power hardware, such as Internet of Things (IoT) devices. Through a lightweight offline pre-computation phase, $I$-$(OT)^2$ shifts the on-transfer computational burden almost entirely to the Sender, while reducing online communication to only six messages and four digests exchanged. We provide a detailed description of the protocol, accompanied by a formal proof of its security. Moreover, to demonstrate the viability of $I$-$(OT)^2$, we also present an open-source proof-of-concept implementation (in C language) evaluated on real IoT hardware. Results are staggering: for 128-bit security using a 3072-bit RSA modulus, the receiver incurs an average online cost per OT as low as 2.80 μs on desktop platforms and 39.90 μs on IoT devices, more than 10$\times$ faster than the well known SimplestOT.

2606.02340 2026-06-02 math.PR math.CO math.ST stat.TH

Transitivity in Inhomogeneous Random Tournaments

非均匀随机锦标赛中的传递性

Sayak Chatterjee, Bhaswar B. Bhattacharya

AI总结 本文通过W-随机锦标赛模型,研究了非均匀随机锦标赛中循环三元组(有向3-圈)数量的波动特征,提出了基于锦标赛乘子自举的一致性系数推断框架,并构建了渐近有效的置信区间算法。

Comments 41 pages, 5 figures

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AI中文摘要

配对比较数据自然地由锦标赛表示,其中传递性对应于存在一个与所有成对结果一致的全局排名。因此,经典的Kendall-Smith一致性系数通过计算循环三元组(有向$3$-圈)的数量来衡量锦标赛中偏离传递性的程度。本文刻画了非均匀随机锦标赛中循环三元组数量的波动特征,并发展了一个关于一致性系数的推断框架。具体而言,我们考虑$W$-随机锦标赛模型,其中比较概率由锦标赛子$W$决定,它是图论中图子在锦标赛背景下的类比。我们证明,对于$n$个顶点的$W$-随机锦标赛,循环三元组的数量呈现出三种不同的波动机制,由$W$的适当正则性和均匀性概念决定。我们进一步发展了一种新颖的锦标赛子乘子自举方法,在相关渐近机制下一致地逼近循环三元组计数的极限分布。结合检验正则性和均匀性的程序,我们设计了一个算法,用于构建对所有锦标赛子渐近有效的一致性系数置信区间。我们还获得了当循环三元组数量的极限分布呈现特定退化时锦标赛子的结构刻画。这些结果也可以通过锦标赛拟随机性的视角来审视,并可能具有独立的意义。

英文摘要

Paired-comparison data are naturally represented by tournaments, where transitivity corresponds to the existence of a global ranking consistent with all pairwise outcomes. Accordingly, the classical Kendall-Smith coefficient of consistency measures deviations from transitivity in a tournament by counting the number of circular triads (directed $3$-cycles). In this paper, we characterize the fluctuations of the number of circular triads in inhomogeneous random tournaments and develop an inferential framework for the consistency coefficient. Specifically, we consider the $W$-random tournament model, where the comparison probabilities are determined by a tournamenton $W$, the analogue of a graphon in the tournament setting. We show that, for a $W$-random tournament on $n$ vertices, the number of circular triads exhibits three different fluctuation regimes, determined by suitable notions of regularity and uniformity of $W$. We further develop a novel tournamenton multiplier bootstrap that consistently approximates the limiting distribution of the circular-triad count in the relevant asymptotic regime. Combining this with procedures for testing regularity and uniformity, we design an algorithm for constructing confidence intervals for the consistency coefficient that is asymptotically valid for all tournamentons. We also obtain structural characterizations of tournamentons for which the limiting distribution of the number of circular triads exhibits specific degeneracies. These results can also be viewed through the lens of tournament quasirandomness and may be of independent interest.

2606.02338 2026-06-02 cond-mat.mes-hall cond-mat.mtrl-sci

Ferroelectric hysteresis in singly aligned graphene-hBN moiré superlattices

单层石墨烯-六方氮化硼莫尔超晶格中的铁电迟滞

Bao Q. Tu, Tanweer Ahmed, Garen Avedissian, Suzanne Lancaster, Mayank Sharma, Kenji Watanabe, Takashi Taniguchi, Fèlix Casanova, Marco Gobbi, Luis E. Hueso

AI总结 通过霍尔测量和温度依赖性实验,证实单层石墨烯-六方氮化硼莫尔超晶格中存在铁电响应,并揭示其源于莫尔超晶格能带导致的异常电荷屏蔽,自发极化从2K持续至室温。

Comments This is the preprint version. Visit publisher's website for the peer reviewed version of record

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AI中文摘要

铁电材料具有维持电极化的独特能力,且该极化可在外加电场下反转。这一特性使其在非易失性随机存取存储器、换能器、执行器和电光调制器等应用中具有价值。最近,在具有非中心对称堆叠顺序的双层石墨烯和六方氮化硼(hBN)莫尔超晶格中,展示了新兴的非传统铁电性。这一现象是否也存在于非中心对称的单层石墨烯(SLG)-hBN莫尔超晶格中仍有争议。在此,我们证明了SLG-hBN莫尔超晶格中的铁电响应。通过霍尔测量,我们将迟滞行为的起源归因于莫尔超晶格能带导致的异常电荷屏蔽,并估算了莫尔超晶格结构中的自发极化幅度。温度依赖性测量证实,迟滞行为从2K持续到室温,为高迁移率、超薄非易失性器件开辟了机会。

英文摘要

Ferroelectric materials have the unique ability to maintain an electric polarization which can be reversed under an external applied electric field. This property makes them valuable for applications such as non-volatile random-access memories, transducers, actuators and electro optic modulators. Recently, emergent unconventional ferroelectricity has been demonstrated in moiré superlattices of bilayer graphene and hexagonal boron nitride (hBN) hosting non centrosymmetric stacking order. Whether this phenomenon is also present in noncentrosymmetric single layer graphene (SLG)-hBN moiré superlattices is still under debate. Here we demonstrate a ferroelectric response in an SLG-hBN moiré superlattice. Through Hall measurements, we pinpoint the origin of the hysteretic behavior to abnormal charge screening due to the moiré superlattice band and estimate the spontaneous polarization magnitude in the moiré superlattice structure. Temperature dependent measurements confirm that the hysteretic behavior persists from 2K up to room temperature, opening opportunities for high-mobility, ultrathin non-volatile devices

2606.02336 2026-06-02 q-fin.PR

VIX options in Bergomi models

Bergomi模型中的VIX期权

Desen Guo, Dan Pirjol, Lingjiong Zhu

AI总结 研究Bergomi模型下VIX期权在短到期和小波动率波动率条件下的领先阶渐近行为,并给出封闭形式的渐近公式。

Comments 46 pages, 3 figures

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AI中文摘要

我们研究了Bergomi模型中VIX期权价格在短到期和小波动率波动率条件下的领先阶渐近行为。考虑了单因子、双因子Bergomi以及N因子模型中的虚值和平值渐近。领先阶渐近以封闭形式获得,并转化为VIX隐含波动率的小到期渐近预测。提供了数值示例以说明封闭形式渐近公式的效率。

英文摘要

We present a study of the leading-order asymptotics for VIX option prices in Bergomi models in the short-maturity and small volatility-of-volatility regimes. Both out-of-the-money (OTM) and at-the-money (ATM) asymptotics are considered for one-factor, two-factor Bergomi and $N$-factor models. The leading-order asymptotics are obtained in closed-form, which are translated into predictions for the small-maturity asymptotics of the VIX implied volatility. Numerical illustrations are provided to illustrate the efficiency of the closed-form asymptotic formulas.

2606.02335 2026-06-02 cond-mat.mtrl-sci math-ph math.MP physics.app-ph physics.comp-ph

Neural Spectral Element Methods for stiff multiphysics PDEs with electrochemical transport benchmarks

神经谱元方法用于刚性问题多物理场PDEs及电化学传输基准测试

Conrard Giresse Tetsassi Feugmo, David Pankaczy

AI总结 提出神经谱元方法(NSEM),通过在固定Legendre-Gauss-Lobatto求积节点上评估网络并使用预计算谱微分矩阵,结合Kosloff-Tal-Ezer坐标映射和网格自由神经mortar框架,在Poisson-Nernst-Planck基准测试中达到10^-4至10^-7相对点态误差,比自适应重采样PINN基线少两个数量级的配点。

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AI中文摘要

神经谱元方法(NSEM)仅在固定的Legendre-Gauss-Lobatto求积节点上评估每个网络,并用预计算的谱微分矩阵替换所有导数调用。由此产生的确定性损失使得有限内存BFGS(L-BFGS)能够达到10^-9至10^-10的残差。Kosloff-Tal-Ezer坐标映射解析电化学边界层,而网格自由的神经mortar框架耦合多元素域。在Huang及其同事的四示例Poisson-Nernst-Planck(PNP)基准测试中,NSEM达到了10^-4至10^-7的相对点态误差,配点数量比自适应重采样PINN基线少两个数量级。在相同的NSEM基础设施内,tanh多层感知器(MLP)和基于基的Legendre Kolmogorov-Arnold网络(KAN)主干均能达到谱精度,其中KAN在1D PNP基准测试中进入L-BFGS吸引域所需的Adam步数大约只有一半。

英文摘要

The Neural Spectral Element Method (NSEM) evaluates each network only at fixed Legendre-Gauss-Lobatto quadrature nodes and replaces all derivative calls with precomputed spectral differentiation matrices. The resulting deterministic loss enables limited-memory BFGS (L-BFGS) to reach residuals of 10^-9 to 10^-10. A Kosloff-Tal-Ezer coordinate map resolves electrochemical boundary layers, while a mesh-free neural mortar framework couples multi-element domains. On the four-example Poisson-Nernst-Planck (PNP) benchmark of Huang and co-workers, NSEM attains 10^-4 to 10^-7 relative pointwise error with two orders of magnitude fewer collocation points than the adaptive-resampling PINN baseline. Both a tanh multilayer perceptron (MLP) and a basis-aligned Legendre Kolmogorov-Arnold Network (KAN) backbone attain spectral accuracy within the same NSEM infrastructure, with the KAN requiring roughly half the Adam steps to enter the L-BFGS basin of attraction on the 1D PNP benchmark.

2606.02334 2026-06-02 cs.DB

Less Is More? When Dataset Context Hurts LLM-Generated Dataset Descriptions

少即是多?当数据集上下文损害LLM生成的数据集描述时

Lisa-Yao Gan, Arunav Das, Johanna Walker, Klaus Diepold, Elena Simperl

AI总结 通过大规模消融实验,研究不同数据集上下文(标题、模式、代表性数据)对LLM生成数据集描述质量的影响,发现模式单独使用会降低叙事质量,而代表性数据部分改善但未提升整体面向人类的质量。

Comments Accepted to ICDE26 KDExLLM Workshop

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AI中文摘要

数据集搜索和重用受到元数据(如自然语言描述)质量的强烈约束,这些描述通常稀疏或不一致。尽管大型语言模型(LLM)可以自动生成此类描述,但关于什么构成好的数据集描述以及LLM实际需要什么数据集上下文,几乎没有经验指导。我们通过一个基于文献的数据集描述质量框架和一项使用来自欧洲数据门户data.europa.eu的252个数据集(1,336个CSV文件)的大规模消融实验来研究这些问题。我们在基线场景和两个消融场景中使用LLM生成描述:(1)仅使用数据集标题,(2)标题和模式,以及(3)标题、模式和代表性数据,并使用LLM作为评判框架和基于我们质量维度的语义描述属性分析进行评估。我们的结果揭示了一致的模式惩罚:仅表模式通常会降低叙事质量,而代表性数据部分恢复了基础性,但没有改善整体面向人类的质量。我们进一步表明,不同的LLM表现出稳定的描述性角色。这些发现为LLM支持的数据发布工作流程提供了实用指导。

英文摘要

Dataset search and reuse are strongly constrained by the quality of metadata such as natural language descriptions, which are often sparse or inconsistent. Although large language models (LLMs) can generate such descriptions automatically, little empirical guidance exists on what makes a good dataset description and what dataset context LLMs actually need. We study these questions through a literature-grounded framework of dataset description quality and a large-scale ablation study using 252 datasets (1,336 CSV files) from the European data portal data.europa.eu. We generate descriptions with LLMs in a baseline scenario and two ablation scenarios: (1) using only dataset titles, (2) titles and schema, and (3) titles, schema and representative data, and evaluate them with an LLM-as-a- judge framework and a semantic descriptive attribute analysis grounded in our quality dimensions. Our results reveal a consis- tent schema penalty: table-schemas alone often degrade narrative quality, while representative data partially restores grounding without improving overall human-facing quality. We further show that different LLMs exhibit stable descriptive personas. These findings provide practical guidance for LLM-supported data publishing workflows.

2606.02333 2026-06-02 cs.AR

O-POPE: High-Frequency Pipelined Outer Product based GEMM acceleration with minimal buffering overhead

O-POPE:基于外积的高频流水线GEMM加速,具有最小缓冲开销

Danilo Cammarata, Angelo Garofalo, Luca Benini

AI总结 提出O-POPE,一种可扩展的外积引擎,通过重用浮点单元流水线寄存器作为缓冲区,实现高利用率、低开销和快速运行频率,在12nm FINFET工艺下达到1GHz(0.72V)操作,相比现有加速器性能提升1.33倍。

Comments To be published in 2026 IEEE Computer Society Annual Symposium on VLSI (ISVLSI)

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AI中文摘要

通用矩阵乘法(GEMM)在现代机器学习工作负载中主导了执行时间和能耗,对硬件效率施加了越来越大的压力。虽然量化降低了计算和数据移动成本,但训练等精度敏感任务仍然需要更高精度的浮点格式。现有的浮点GEMM加速器面临工作频率、算术利用率和缓冲开销之间的权衡。本文提出O-POPE,一种可扩展的外积引擎,通过重用浮点单元(FPU)流水线寄存器作为缓冲区,同时实现高利用率、低开销和快速运行频率。该解决方案利用了输出固定外积执行的数据重用优势,并在12nm FINFET工艺下实现了1GHz(0.72V)操作,对于2048个MAC配置,缓冲区面积小于2%。我们的评估表明,与最先进的浮点GEMM加速器相比,O-POPE实现了高达99.97%的FPU利用率,并提高了性能(1.33倍)、性能密度(9%)和能效(8%)。

英文摘要

General matrix multiply (GEMM) dominates both execution time and energy consumption of modern machine learning (ML) workloads, placing increasing pressure on hardware efficiency. While quantization mitigates computational and data movement costs, accuracy-sensitive tasks such as training still require higher-precision floating-point formats. Existing floating-point GEMM accelerators face trade-offs between operating frequency, arithmetic utilization, and buffering overhead. This work presents O-POPE, a scalable outer-product engine that achieves concurrently high utilization, low overhead, and a fast operating frequency by repurposing floating-point unit (FPU) pipeline registers as buffers. This solution leverages the data-reuse advantages of output-stationary outer-product execution and enables 1 GHz (0.72 V) operation in 12 nm FINFET technology with less than 2% buffer area for a 2048-MACs configuration. Our evaluation shows that O-POPE achieves up to 99.97% FPU utilization and improves performance (1.33x), performance density by 9%, and energy efficiency by 8%, compared to state-of-the-art floating-point GEMM accelerators.

2606.02330 2026-06-02 astro-ph.SR

Solar vortex detection methods in MHD simulations: impact of magnetic field and spatial resolution

MHD模拟中的太阳涡旋检测方法:磁场和空间分辨率的影响

M. Koll Pistarini, E. Khomenko, T. Felipe, M. Modestov

AI总结 本研究通过分析不同磁场配置和空间分辨率下的三维太阳大气模拟,使用涡旋强度法和SWIRL代码检测涡旋,发现磁场和分辨率显著影响涡旋的覆盖面积、数量、大小及温度分布,且检测方法对统计结果有影响。

Comments Accepted for publication in A&A, 17 pages, 10 figures

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AI中文摘要

本文旨在研究不同磁场配置和空间分辨率对涡旋结构的影响。我们分析了六组三维真实太阳大气模拟,涉及三种磁场配置:小尺度发电机以及两种初始垂直植入的50 G和200 G磁场。采用了三种空间分辨率:20x20x14、10x10x7和5x5x3.5 km^3。我们对所有模型应用了两种基于速度梯度张量的涡旋检测方法:涡旋强度法和SWIRL代码。我们比较了两种方法得到的涡旋位置,并对涡旋生成机制、涡旋覆盖面积、数量、特征尺寸以及温度随高度变化进行了统计分析。我们证实了不同的磁场配置和空间分辨率会影响涡旋的覆盖面积、数量和尺寸。同样,检测方法也会影响统计结果。涡旋强度法能检测任意方向的涡旋,但需要高度依赖的阈值。SWIRL仅检测垂直方向的涡旋,但与旋转水平速度场吻合更好。50 G垂直磁场模拟支持形成没有光球对应物的色球涡旋,而200 G模型中大多数涡旋直接将光球与色球连接。小尺度发电机模拟以大量水平涡旋为特征,色球层几乎不存在垂直涡旋。涡旋的温度分布证实,无论模拟设置如何,涡旋都比周围环境更热。

英文摘要

The aim of this paper is to investigate the influence of different magnetic field configurations and spatial resolutions on vortex structures. We analyzed a set of six three-dimensional realistic simulations of the solar atmosphere under three different magnetic field configurations: a small-scale dynamo and two initially vertical implanted magnetic fields of 50 G and 200 G. Three different spatial resolutions have been employed: 20x20x14, 10x10x7 and 5x5x3.5 km^3. We applied two vortex detection methods based on the velocity gradient tensor to all of the models: swirling strength and the SWIRL code. We performed a comparison of vortex locations obtained with both methods, and a statistical analyses of the vortex generation mechanisms, the area covered by vortices, their number and characteristic sizes, and temperature profiles as a function of height. We have confirmed that different magnetic field configurations and spatial resolutions impact the area coverage, number, and sizes of vortices. Likewise, the detection methods impact the statistics obtained. Swirling strength detects vortices with any orientation but a height-dependent threshold is needed. SWIRL only detects vertically-oriented vortices but shows a better agreement with the rotating horizontal velocity field. Simulations with a vertical magnetic field of 50 G support the formation of chromospheric vortices without a photospheric counterpart, while most of the vortices in the 200 G model directly connect the photosphere with the chromosphere. Small-scale dynamo simulations are characterized by a large number of horizontal vortices, with vertical vortices being nearly absent at chromospheric layers. Temperature profiles of vortices confirm that they are hotter than their surroundings, regardless the simulation setup.

2606.02327 2026-06-02 eess.AS

Exploiting Noise Inseparability for Weakly-Supervised Discriminative Speech Denoising Using Noisy Targets

利用噪声不可分离性进行基于噪声目标弱监督判别语音去噪

Matthew Maciejewski, Samuele Cornell

AI总结 提出一种利用噪声估计抵消语音估计中残留噪声的方法,通过联合训练人工和自然噪声混合物实现领域自适应,在WHAM!和CHiME-3基准上验证有效性。

Comments Submitted to IWAENC 2026

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AI中文摘要

语音去噪不仅是人类听觉的常见需求,也是下游处理系统在嘈杂真实声学条件下缺乏鲁棒性时的必要步骤。不幸的是,去噪问题中传统的域内监督训练并非易事,因为训练目标无法由人工标注:生成自然噪声语音记录的干净版本本身就是待解决的任务。监督训练通常通过向干净语音录音人工添加噪声来进行,这些噪声只能来自受控领域,由于神经网络的域外泛化能力差,这是一个重大限制。另一种方法是噪声目标训练(NyTT),它简单地将干净语音替换为域内噪声记录,希望学习去除人工噪声能推广到自然噪声。尽管NyTT显示出有希望的结果,但其训练目标并非由干净语音估计最小化。我们表明,除了估计自然噪声语音外,同时估计人工噪声,实际上可以利用不良最优解:通过简单减法,语音估计中的残留噪声可以被噪声估计抵消。关键是,该最优解与常规人工混合物完全兼容,使得能够使用两种类型的数据进行联合训练,优化目标一致,从而为改进领域适应性打开了大门。我们通过WHAM!和CHiME-3基准测试证明了我们方法的有效性。

英文摘要

Speech denoising is an often necessary step not only for human listening, but also for downstream processing by systems lacking robustness to noisy, real-world acoustic conditions. Unfortunately, denoising is a problem where conventional in-domain supervised training is not trivial, as the training targets cannot be annotated by humans: producing a clean version of a naturally-noisy speech recording is itself the task to solve. Supervised training is typically performed through the artificial addition of noise to clean speech recordings, which can only be sourced from controlled domains, a significant limitation due to the poor out-of-domain generalization of neural networks. An alternative is noisy target training (NyTT), which simply replaces the clean speech with in-domain noisy recordings, with the hope that learning to remove the artificial noise will extend to the natural. Though having shown promising results, NyTT's training objective is not minimized by clean speech estimates. We show that by estimating the artificial noise in addition to the naturally-noisy speech, the undesirable optimum can actually be exploited: the residual noise in the speech estimate can be canceled by the noise estimate via simple subtraction. Crucially, the optimum is fully compatible with conventional artificial mixtures, enabling joint training using both types of data with consistent optimization targets, opening the door to improved domain adaptability. The effectiveness of our approach is demonstrated through WHAM! and CHiME-3-based benchmarks.

2606.02325 2026-06-02 cs.DS cs.DM

Terminal Steiner tree problem : Complexity and Algorithms

终端斯坦纳树问题:复杂性与算法

Jyothish S, Sadagopan Narasimhan

AI总结 研究终端斯坦纳树的存在性、不同图类上的复杂性、斯坦纳树问题的黑箱应用,以及关于终端数量的固定参数可解算法。

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AI中文摘要

给定一个连通图 $G$ 和一个终端集 $R \subseteq V(G)$,斯坦纳树问题 (ST) 要求一棵树,该树包含 $R$ 中的所有顶点,并且至多包含 $r$ 个来自 $V(G)\backslash R$ 的顶点,其中 $r\geq 0$ 为整数。已知 (Garey et al.,1977) ST 是 NP-完全的。所有终端顶点都被限制为叶子的斯坦纳树称为终端斯坦纳树。我们的研究探讨了终端斯坦纳树的存在性、其在不同图类上的复杂性、ST 的黑箱应用,以及一个关于终端数量的固定参数可解 (FPT) 算法。

英文摘要

Given a connected graph $G$ and a terminal set $R \subseteq V(G)$, the Steiner tree problem (ST) asks for a tree that spans all of $R$ with at most $r$ vertices from $V(G)\backslash R$, for some integer $r\geq 0$. It is known from (Garey et al.,1977 ) that ST is NP-complete. A Steiner tree in which all terminal vertices are constrained to be leaves is called a terminal Steiner tree. Our study addresses the existence of a terminal Steiner tree, its complexity across various graph classes, black-box applications of the ST, and a fixed-parameter tractable (FPT) algorithm with respect to the number of terminals.

2606.02324 2026-06-02 math.NT

Cyclotomic factors of rational necklace functions

有理项链函数的分圆因子

Nguyen Cao Minh, Nguyen Vu Hoang Minh, Dung Nguyen, Tung T. Nguyen, Nguyen Duy Tan, Duong Tran

AI总结 本文引入有理项链函数统一项链多项式和Fekete多项式,研究其分圆因子,揭示伽罗瓦群在产生新分圆因子中的隐藏作用。

Comments Comments are welcome!

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AI中文摘要

项链多项式出现在数学的各个领域,包括组合学、李理论和有限域上的伽罗瓦理论。近年来,它们的算术性质得到了广泛研究。在本文中,我们引入了一类新的有理项链函数,它统一了两个研究充分的 polynomial 族:项链多项式和Fekete多项式。我们描述了分圆多项式作为这些有理项链函数的因子的几种方式。我们的结果统一并推广了先前关于项链多项式和Fekete多项式的各种工作。特别地,我们描述了一个令人惊讶的现象,其中某些伽罗瓦群在出现这些先前工作未涵盖的新分圆因子中扮演了隐藏角色。

英文摘要

Necklace polynomials arise in various fields of mathematics, including combinatorics, Lie theory, and Galois theory over finite fields. Their arithmetic properties have been extensively studied in recent years. In this article, we introduce a new class of rational necklace functions that unifies two well-studied families of polynomials: necklace polynomials and Fekete polynomials. We describe several ways in which cyclotomic polynomials appear as factors of these rational necklace functions. Our results unify and generalize various earlier work on necklace polynomials and on Fekete polynomials. In particular, we describe a surprising phenomenon in which certain Galois groups play a hidden role in the appearance of new cyclotomic factors that are not covered by these previous works.

2606.02319 2026-06-02 cs.DC

Strategies for Molecular Dynamics using Hybrid Systems: LAMMPS Use Case

使用混合系统的分子动力学策略:LAMMPS 用例

Paulo Henrique Leme Ramalho, Dennis Alves Pedersen, Fábio Andrijauskas

AI总结 本文以抗菌肽Tritrpticin为工作负载,系统分析了LAMMPS模拟器在粗粒化生物分子模拟中的纯MPI与混合MPI+OpenMP性能,发现纯MPI在多节点扩展性差,而混合策略在大规模下更高效。

Comments 19 pages, 9 figures

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AI中文摘要

生物分子模拟的复杂性显著增加了对高性能计算(HPC)基础设施的需求,特别是在分子动力学和粗粒化建模中。本工作以抗菌肽Tritrpticin(PDB ID: 1D6X)作为实验工作负载,对LAMMPS模拟器在粗粒化生物分子模拟中的性能和可扩展性进行了系统分析。在包含最多8个计算节点和1024个同时核心的HPC环境中评估了纯MPI和混合MPI+OpenMP执行。研究了执行时间、加速比、并行效率、统计变异性和内部时间分解等指标。结果表明,纯MPI执行在单节点环境中表现出色,但由于通信开销和进程间同步,在多节点执行中可扩展性下降。混合MPI+OpenMP配置在大规模下更高效,减少了通信成本并更好地利用了NUMA内存层次结构。计算分解显示,在最大纯MPI规模下,通信和静电相互作用例程占执行时间的最大部分。这些结果强化了生物分子HPC应用的性能直接取决于并行化粒度、空间分解和分布式通信成本之间的平衡。混合MPI+OpenMP策略代表了在现代众核架构上进行粗粒化生物分子模拟的更可持续的替代方案。

英文摘要

The complexity of biomolecular simulations has substantially increased the demand for High-Performance Computing (HPC) infrastructures, particularly in molecular dynamics and coarse-grained modeling. This work presents a systematic performance and scalability analysis of the LAMMPS simulator for coarse-grained biomolecular simulations, using the antimicrobial peptide Tritrpticin (PDB ID: 1D6X) as the experimental workload. Pure MPI and hybrid MPI+OpenMP executions were evaluated in HPC environments comprising up to 8 compute nodes and 1024 simultaneous cores. Metrics of execution time, speedup, parallel efficiency, statistical variability, and internal time decomposition were investigated. Results showed that pure MPI executions deliver excellent performance in single-node environments but suffer scalability degradation in multi-node executions due to communication overhead and inter-process synchronization. Hybrid MPI+OpenMP configurations proved more efficient at large scale, reducing communication costs and better exploiting the NUMA memory hierarchy. The computational breakdown revealed that communication and electrostatic interaction routines accounted for the largest fraction of execution time at the largest pure-MPI scales. These results reinforce that performance of biomolecular HPC applications depends directly on the balance among parallelization granularity, spatial decomposition, and distributed communication costs. Hybrid MPI+OpenMP strategies represent a more sustainable alternative for coarse-grained biomolecular simulations on modern many-core architectures.

2606.02318 2026-06-02 astro-ph.HE astro-ph.CO gr-qc

The First Detection of Sub-Populations in the Delay-Time Distribution of Binary Black Holes in GWTC-4 of LIGO-Virgo-KAGRA

LIGO-Virgo-KAGRA GWTC-4中双黑洞延迟时间分布子群的首次探测

Shaunak Padhyegurjar, Suvodip Mukherjee

AI总结 利用LIGO-Virgo-KAGRA第四次引力波目录(GWTC-4),首次测量了双黑洞合并延迟时间分布与源性质的相关性,识别出三个具有不同合并率行为的子群,并发现高质量源(>45 M☉)的延迟时间分布显著不同,且与质量比和自旋强相关。

Comments 12 pages, 6 figures and 1 appendix. Comments are welcome!

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AI中文摘要

双黑洞(BBHs)不同形成通道的印记编码在BBH合并与其前身星形成之间的时间延迟分布中,以及它们的源性质如成分质量、质量比、自旋等。这使得延迟时间分布与致密天体源性质之间可能存在相关性。我们报告了来自LIGO-Virgo-KAGRA第四次引力波目录(GWTC-4)的首次测量,并识别出三个子群,它们表现出不同的合并率行为。我们发现质量高于45 M☉的源的延迟时间分布与低于该质量的源显著不同,并且对质量比和自旋有强烈依赖,表明接近相等质量和接近零有效自旋的引力波源比其它情况延迟更多。我们的分析识别出至少三个依赖于源性质的合并率子群,在红移z=0处,三个不同子群的合并率从约0.6到12 Gpc⁻³ yr⁻¹不等,因此排除了所有通过引力波探测到的BBHs的普适合并率。

英文摘要

The imprint of different formation channels of binary black holes (BBHs) is encoded in the distribution of time delays between BBH mergers and the formation of their progenitor stars, along with their source properties such as component mass, mass-ratio, spin, and more. This makes it possible for the presence of a potential correlation between the delay-time distribution and compact-object source properties. We report the first measurement of this inevitable signature from the fourth gravitational wave (GW) catalog (GWTC-4) of LIGO-Virgo-KAGRA and identified three sub-populations that show distinct merger rate behavior as a consequence of this. We find that the delay-time distribution of the sources above a mass of $45$ M$_\odot$ is significantly different from the ones below and exhibits strong dependence on the mass-ratio and spin, indicating that GW sources close to equal masses and close to zero effective spin are more delayed in comparison to the values otherwise. Our analysis identifies the presence of at least three source property dependent sub-population of merger rates with the merger rate at redshift $z=0$ varying from $\sim 0.6- 12$ Gpc$^{-3}$ yr$^{-1}$ for the three different sub-populations and hence rule out a Universal merger rate for all the BBHs detected using GW.

2606.02317 2026-06-02 cond-mat.mtrl-sci

Surface Modification for III-V Selective Area Molecular Beam Epitaxy of Non-Selective Mask Materials

非选择性掩模材料的III-V族选区分子束外延表面改性

Ashlee M. García, Byron D. Aguilar, William J. Doyle, Pernille Undrum Fathi, Federico Capasso, Daniel Wasserman, Seth R. Bank

AI总结 本研究评估了Al₂O₃、TiO₂和HfO₂等替代掩模材料在GaAs选区分子束外延中的沉积选择性,并通过表面改性技术(如薄SiO₂覆盖层)实现了高非选择性甚至反应性掩模材料的选择性生长。

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AI中文摘要

通过分子束外延进行III-V族半导体的选区嵌入式再生长,能够将金属和电介质无缝集成到晶体材料中,用于光电器件的新型设计。然而,传统的掩模材料如$SiO_2$和$Si_{3}N_{4}$由于在技术相关波长下具有高消光系数,限制了红外波段高对比度光子学的设计。因此,需要探索替代掩模材料,以扩展选区分子束外延的能力,超越传统使用的材料。本研究评估了替代材料$Al_{2}O_{3}$、$TiO_2$和$HfO_2$薄膜的沉积选择性,这些薄膜具有更优的光谱响应但表面反应性更高。结果发现,$Al_{2}O_{3}$在典型的GaAs生长温度下表现出有前景的选择性生长特性;$HfO_2$在高达650°C的温度下表现出高非选择性,主要由Ga在掩模上的吸附主导;而$TiO_2$在沉积过程中被证明具有反应性。为了实现高非选择性甚至反应性掩模材料的选择性生长,采用了一种表面改性技术来改善任何给定薄膜的选择性生长特性。通过应用薄$SiO_2$覆盖层,利用GaAs/$SiO_2$体系的典型生长条件,实现了$Si_{3}N_{4}$和$TiO_2$薄膜的选择性生长。研究了$SiO_2$覆盖层厚度与生长选择性之间的关系,揭示亚纳米级覆盖层能显著影响掩模表面化学,表明通过沉积薄层$SiO_2$,可以在不降低光学响应的情况下实现任何掩模材料的$SiO_2$类选择性。

英文摘要

Selective-area embedded regrowth of III-V semiconductors by molecular beam epitaxy enables the seamless integration of metals and dielectrics into crystalline material for novel design of optoelectronic devices. However, traditional masks like $SiO_2$ and $Si_{3}N_{4}$ limit the design of high-contrast photonics in the infrared due to their high extinction coefficients at technologically relevant wavelengths. Consequently, there is a need to explore alternative mask materials to expand the selective area molecular beam epitaxy capabilities beyond those traditionally used. This study evaluates the deposition selectivity of the alternative materials $Al_{2}O_{3}$, $TiO_2$, and $HfO_2$, films with preferable spectral responses but higher surface reactivity. It was found that $Al_{2}O_{3}$ exhibits promising selective growth characteristics within typical GaAs growth temperatures, $HfO_2$ demonstrated a high non-selectivity dominated by Ga adsorption on the mask at temperatures up to 650 $^\circ$C, and $TiO_2$ proved reactive during deposition. To achieve selective growth of highly non-selective and even reactive mask materials, a surface modification technique was employed to improve the selective growth characteristics of any given film. Selective growth of $Si_{3}N_{4}$ and $TiO_2$ films was achieved with the application of a thin $SiO_2$ capping layer utilizing growth conditions typical of the GaAs/$SiO_2$ system. The relationship between the thickness of $SiO_2$ caps and growth selectivity was examined, revealing that sub-1 nm capping layers can significantly influence the mask surface chemistry, indicating that by depositing a thin layer of $SiO_2$, $SiO_2$-like selectivity for any mask material can be realized without degrading its optical response.

2606.02316 2026-06-02 math.LO

Uniform Bounds in D-Minimal Structures

D-极小结构中的一致界

Madie Farris, Philipp Hieronymi

AI总结 本文证明了在实数域的任何扩张中,若每个可定义子集要么有内点要么是离散集的有限并,则对任意可定义子集A⊆R^{n+1}存在一致界N使得每个纤维A_x要么有内点要么是N个离散集的并。

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AI中文摘要

设 $\mathcal{R}$ 是实数域的一个扩张,使得 $\mathbb{R}$ 中在 $\mathcal{R}$ 中可定义的每个子集要么有内点,要么是离散集的有限并。回答 Chris Miller 的一个问题,我们证明:对每个 $n\in \mathbb{N}$ 和每个可定义子集 $A\subseteq \mathbb{R}^{n+1}$,存在 $N\in \mathbb{N}$ 使得对所有 $x\in \mathbb{R}^n$,要么 $A_x$ 有内点,要么是 $N$ 个离散集的并。

英文摘要

Let $\mathcal{R}$ be an expansion of the real field such that every subset of $\mathbb{R}$ definable in $\mathcal{R}$ either has interior or is a finite union of discrete sets. Answering a question by Chris Miller, we show that for every $n\in \mathbb{N}$ and every definable subset $A\subseteq \mathbb{R}^{n+1}$ there is $N\in \mathbb{N}$ such that for all $x\in \mathbb{R}^n$ either $A_x$ has interior or is the union of $N$ discrete sets.

2606.02315 2026-06-02 physics.flu-dyn math-ph math.MP

Identifying sensitivity-dominant parameters via active subspaces in reduced-order modeling of fluid dynamics

通过流体动力学降阶建模中的活动子空间识别敏感性主导参数

Dewu Yang, Rui Wang, Pengyu Lai, Junjie Wang, Feng Wang, Hui Xu

AI总结 提出POD-AS-PRS框架,结合本征正交分解、活动子空间和残差神经网络,在状态和参数空间双重降维,通过敏感性分析识别主导参数,实现高效高保真感兴趣量重构。

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AI中文摘要

降阶模型广泛用于当全阶模型模拟计算代价高昂时描述复杂系统动力学。本研究提出POD-AS-PRS,一种基于活动子空间技术的新型模型降阶框架,在状态和参数空间同时进行降维,实现对感兴趣量的高效高保真近似。该方法采用本征正交分解从CFD快照中提取低维系数,作为具有线性层的残差神经网络的输入,学习其到感兴趣量的非线性映射。利用反向模式自动微分计算关于系数的梯度,通过将分析转移到POD系数空间,使活动子空间分析能够识别有影响的模态,从而实现由感兴趣量敏感性而非模态能量驱动的双重降维。随后,基于活动子空间导出的活动变量,使用多项式响应面构建代理模型,仅保留高影响力的POD系数,确保准确高效的感兴趣量重构。该框架在周期性和混沌钝体流动上得到验证,以少量有影响力的参数实现了高精度,而基于自动微分的梯度比有限差分近似实现了两个数量级的加速。敏感性分析进一步揭示,有影响力的系数不一定与模态能量成比例,突出了关键流动结构。因此,POD-AS-PRS识别了一个控制感兴趣量的敏感性主导参数的低维流形,阐明了基本流动结构及其与控制参数的耦合,从而实现了高效准确的感兴趣量重构。

英文摘要

Reduced-order models (ROMs) are widely employed to describe complex system dynamics when simulations with full-order models (FOMs) are computationally prohibitive. This study presents POD-AS-PRS, a novel model-reduction framework based on the active subspaces (AS) technique, which performs dimensionality reduction in both the state and parameter spaces, enabling efficient and high-fidelity approximations of quantities of interest (QoI). The approach employs proper orthogonal decomposition (POD) to extract low-dimensional coefficients from CFD snapshots, which are inputs to a residual neural network (ResNet) with linear layers to learn their nonlinear mapping to QoI. Reverse-mode automatic differentiation (AD) is utilized to compute gradients with respect to the coefficients, enabling AS analysis to identify influential modes by shifting the analysis to the POD coefficient space, thereby achieving a dual-stage dimensionality reduction driven by QoI sensitivity rather than modal energy. A surrogate model is subsequently constructed using a polynomial response surface (PRS) based on AS-derived active variables, retaining only the highly influential POD coefficients to ensure accurate and efficient QoI reconstruction. The framework is validated on periodic and chaotic bluff-body flows, demonstrating high accuracy with few influential parameters, while AD-based gradients achieve a two-order-of-magnitude speed-up over finite-difference approximations. Sensitivity analysis further reveals that the influential coefficients are not necessarily proportional to modal energy, highlighting the critical flow structures. Consequently, POD-AS-PRS identifies a low-dimensional manifold of sensitivity-dominant parameters that govern the QoI, elucidating the essential flow structures and their coupling with control parameters, thereby enabling efficient and accurate QoI reconstruction.

2606.02314 2026-06-02 cs.NI

Discovering Agents for Discovery: The Case for DNS

发现智能体:DNS 的案例

Ramachandra Rao Seethiraju, Sameer Thakar, Karthik Shyamsunder, Eric Osterweil

AI总结 本文提出利用 DNS 作为 AI 智能体发现的基础设施,通过评估导航完整性、查找复杂性和事务性能,证明 DNS 能够以低延迟和低数据量支持大规模智能体发现。

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AI中文摘要

随着人工智能(AI)智能体进入在互联网上普遍部署的下一个阶段,它们的可发现性将成为核心挑战。AI 智能体需要发现彼此的信息、如何定位这些信息、如何促进认证、完整性和授权、如何跨不同平台连接以及如何跨组织边界扩展,这些构成了一系列未解决的挑战,而部署成功将促使这些挑战得到解决。这些挑战正是互联网最古老、最稳固、最普遍的基础设施之一——域名系统(DNS)所理想适合的。这样一个丰富、已经普遍存在且可编程灵活的基础是 AI 智能体发现的理想选择。在这项工作中,我们提出了 AI 智能体发现所需基本语义的说明和理由。我们认为三个关键评估标准将变得至关重要:导航完整性(发现解决方案中包含必要元数据(如信任元素)的程度)、查找复杂性和事务性能(例如延迟、速度或时效性)。使用关于 119,757 个真实服务端点和多个智能体工具生态系统的数据,我们实证评估了第一个考虑因素,以说明使用 DNS 进行 AI 智能体发现的适用性。我们的结果表明,所需数据的大小和数量完全在单个 DNS UDP 事务的范围内,其延迟可以达到毫秒级。我们的评估展示了在互联网规模上实现 AI 智能体可发现性的有希望的路径,从而加速安全、稳定和有弹性的 AI 智能体部署。

英文摘要

As Artificial Intelligence (AI) agents enter their next stage of being deployed ubiquitously throughout the Internet, their discoverability will become a central challenge. The information AI agents need to discover one another, how they will locate it, how to facilitate authentication, integrity, and authorization, how to connect across different platforms, and how to scale across organizational boundaries form a set of unanswered challenges that deployment success will prompt. These are challenges for which one of the Internet's most venerable, solid, and ubiquitous infrastructures is ideally suited: The Domain Name System (DNS). Such a rich, already ubiquitous, and programmatically flexible foundation is an ideal option for discovery of AI agents. In this work, we propose an illustration and rationale for the basic semantics that discovery for AI agents will require. We argue that three key evaluation criteria will become paramount: navigational completeness (the extent to which the necessary metadata, with elements like trust, is included in a discovery solution), lookup complexity, and transaction performance (e.g., latency, speed, or recency). Using data about 119,757 real-world service endpoints and multiple agent tooling ecosystems, we empirically evaluate the first of these considerations to illustrate the appropriateness of using DNS for AI agent discovery. Our results show the size and amount of data necessary are well within the range of a single DNS UDP transaction, whose latency can be on the order of milliseconds. Our evaluations illustrate a promising path toward enabling AI agent discoverability at the Internet's scale, and thereby accelerating secure, stable, and resilient AI agent deployments.

2606.02312 2026-06-02 math.NT

Arithmetic regularity as an alternative to transference

算术正则性作为转移的替代方案

Sam Chow, Sean Prendiville, Santiago Vazquez

AI总结 本文提出用算术正则性方法替代傅里叶分析转移原理,以处理稀疏算术集中的组合定理,并给出一个包含线性方程和高次方程系统的正确下界。

Comments 50 pages

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AI中文摘要

自Green(2005)以来,傅里叶分析转移原理主导了与稀疏算术集相关的组合定理领域。我们展示了一种使用算术正则性的不同方法。这种方法更加通用,并且在没有明显的“稠密模型”时有可能成功。此外,我们认为,正如传统的圆法将算术问题分解为可以单独解决的实部和p-adic部分一样,算术正则性方法将其推广,产生一个额外的“组合”因子。这个框架直接导致稠密集中配置数量的正确下界。我们用一个包含线性方程和高次方程的系统来说明这一点。

英文摘要

Since Green (2005), the Fourier-analytic transference principle has dominated the landscape of combinatorial theorems relative to sparse arithmetic sets. We demonstrate a different approach using arithmetic regularity. This is more versatile and has the potential to succeed when no obvious `dense model' is forthcoming. Moreover, we contend that, just as the traditional circle method disassembles an arithmetic problem into real and $p$-adic parts which can be solved individually, the arithmetic regularity method generalises this to yield an additional `combinatorial' factor. This framework leads directly to a correct lower bound on the number of configurations in a dense set. We illustrate this using a system comprising a linear equation together with a higher-degree equation.

2606.02311 2026-06-02 cs.PF math.PR

$γ$-CounterBoost: Optimizing response time tails using job type information only

$γ$-CounterBoost:仅使用作业类型信息优化响应时间尾部

Nils Charlet, Benny Van Houdt

AI总结 针对部分作业大小信息场景,提出$γ$-CounterBoost策略,在不利用到达时间的情况下最小化轻尾M/G/1队列响应时间尾部,并证明其在更广泛的Contextual CounterBoost策略类中最优。

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AI中文摘要

在最近的一篇论文中,$γ$-Boost调度策略被证明可以最小化轻尾M/G/1队列中响应时间分布的尾部。该策略使用提升到达时间调度作业,定义为作业的到达时间减去其提升量,其中作业的提升量取决于其确切大小。当仅有部分作业大小信息可用时,例如传入作业的类型,也可以使用$γ$-Boost策略。在这种情况下,作业的提升量$b_i$仅取决于其类型$i$,并且$γ$-Boost被证明在所有提升策略中优化了尾部,其中提升策略完全由$b_i$值决定。在部分信息设置中,$γ$-Boost依赖于两种信息:作业类型和到达时间。 本文关注在部分作业大小信息设置中,当调度器仅使用作业类型且不利用到达时间时,最小化轻尾M/G/1队列尾部的问题。先前的工作表明,在2种作业类型的情况下,所谓的Nudge-$M$策略在一大类调度策略中最小化了尾部。在本文中,我们引入了$γ$-CounterBoost策略,用于具有$d \geq 2$种作业类型的部分信息设置,并证明它在更广泛的称为Contextual CounterBoost策略的调度策略类中最小化了尾部。当$d=2$种作业类型时,$γ$-CounterBoost策略退化为Nudge-$M$策略。

英文摘要

In a recent paper the $γ$-Boost scheduling policy was shown to minimize the tail of the response time distribution in a light-tailed M/G/1-queue. This policy schedules jobs using a boosted arrival time, defined as the arrival time of a job minus its boost, where the boost of a job depends on its exact job size. The $γ$-Boost policy can also be used when only partial job size information is available, such as the type of an incoming job. In such case the boost $b_i$ of a job depends solely on its type $i$ and $γ$-Boost was shown to optimize the tail among all boost policies, where a boost policy is fully determined by the $b_i$ values. In the partial information setting $γ$-Boost relies on two types of information: job types and arrival times. This paper focuses on the problem of minimizing the tail in a light-tailed M/G/1-queue in the partial job size information setting when the scheduler only makes use of the job types and {\it does not exploit arrival times}. Prior work showed that in case of $2$ job types the so-called Nudge-$M$ policy minimizes the tail in a large class of scheduling policies. In this paper we introduce the $γ$-CounterBoost policy in the partial information setting with $d \geq 2$ job types and prove that it minimizes the tail in an even broader class of scheduling policies called Contextual CounterBoost policies. The $γ$-CounterBoost policy reduces to the Nudge-$M$ policy in case of $d=2$ job types.

2606.02308 2026-06-02 math.DS

Recurrence, symbolic dynamics, and wild attractors for unimodal maps

单峰映射的递归、符号动力学与野吸引子

Lori Alvin, Jernej Činč

AI总结 本文通过符号动力学研究临界轨道递归性质与野Cantor吸引子的关系,构造了具有野吸引子的非重整化单峰映射族,并证明了长分支组合与持续递归的不兼容性。

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AI中文摘要

本文构造了具有野Cantor吸引子的单峰映射族,并通过符号动力学研究临界轨道递归性质之间的相互作用。利用揉捏和共揉捏技术,我们提供了持续递归的符号刻画,用切割和共切割时间表示,并将其与其他递归条件(包括Collet–Eckmann条件)联系起来。作为应用,我们获得了足够高阶临界阶的非重整化单峰映射的不可数族,这些映射允许野吸引子。我们还分析了递归状态下后临界动力学的结构,构造了嵌入里程计和临界$ω$-极限集上极小同胚动力学的例子,并证明了极小同胚与正则递归并不蕴含共轭于加法机。最后,我们证明了长分支组合与持续递归不兼容,从而澄清了不同递归状态之间的边界。

英文摘要

In this paper, we construct families of unimodal maps with wild Cantor attractors and study, via symbolic dynamics, the interplay between recurrence properties of the critical orbit. Using kneading and co-kneading techniques, we provide a symbolic characterization of persistent recurrence in terms of cutting and co-cutting times, and relate it to other recurrence conditions, including the Collet--Eckmann condition. As an application, we obtain uncountable families of non-renormalizable unimodal maps of sufficiently high critical order admitting wild attractors. We also analyze the structure of postcritical dynamics in recurrent regimes, constructing examples with embedded odometers and with minimal homeomorphic dynamics on the critical $ω$-limit set, and showing that a minimal homeomorphism together with regular recurrence does not imply conjugacy to an adding machine. Finally, we prove that longbranched combinatorics is incompatible with persistent recurrence, thereby clarifying the boundary between different recurrence regimes.

2606.02306 2026-06-02 econ.TH

Delusions of Grandeur and Their Benefits (and Hazards)

妄自尊大的幻觉及其益处(与风险)

Cooper Howes, Can Urgun, Mark Whitmeyer

AI总结 本文通过群体锦标赛模型研究代理人对环境信念(乐观主义)如何影响产出与不平等,发现乐观虽提高总产出但加剧不平等,并与实证中不平等与创业的正相关关系相联系。

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AI中文摘要

我们研究了一个群体范围内的锦标赛,其中代理人既关心自己的绝对财富也关心相对财富,通过搜索相关对象进行实验。我们探讨了代理人对环境信念的作用,即对应于他们实验的随机过程。我们发现,尽管乐观导致更高的产出,但也产生了更大的不平等。我们将这些观察结果与表明不平等与创业之间存在正相关关系的实证证据联系起来。

英文摘要

We study a population-wide tournament in which agents, who care both about their absolute and relative wealth, experiment by searching over correlated objects. We explore the role of the agents' beliefs about the environment; namely, the stochastic processes corresponding to their experimentation. We find that although optimism leads to higher output, it also produces greater inequality. We connect these observations with empirical evidence suggesting a positive relationship between inequality and entrepreneurship.

2606.02305 2026-06-02 q-bio.NC cs.HC

Mapping Whisper Representations to Human ECoG Responses with Interpretable Time-Resolved Neural Encoding

将Whisper表示映射到人类ECoG响应:可解释的时间分辨神经编码

Matteo Ciferri, Tommaso Boccato, Michal Olak, Matteo Ferrante, Nicola Toschi

AI总结 通过时间分辨神经编码器结合语音嵌入与循环时间模型及软注意力,研究Whisper内部表示如何预测颅内ECoG响应,发现中间层与神经活动对应最强,且高分辨率ECoG受益于时间结构化建模。

Comments Presented at ICLR 2026 Workshop on Representational Alignment (Re-Align)

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AI中文摘要

理解语音基础模型如何与人类皮层活动相关是计算神经科学的一个关键挑战。在这里,我们研究了Whisper的内部表示如何在自然语音感知过程中预测颅内ECoG响应。我们引入了一个时间分辨神经编码器,将语音嵌入与循环时间模型和软注意力相结合,从而能够检查逐层的大脑对齐。中间Whisper层与神经活动提供了最强的对应关系,支持模型表示与皮层语音处理之间的层次匹配。与基线的比较表明,高分辨率ECoG响应受益于超出相同语音表示的线性映射的时间结构化建模。此外,注意力图揭示了语音嵌入与神经响应之间的时间局部对齐,而音位可解释性分析在编码信息电极中识别出解剖学上一致的音位类别组织。这些结果共同表明,语音基础模型为研究时间分辨的皮层语音表示提供了一个有用的框架。

英文摘要

Understanding how speech foundation models relate to human cortical activity is a key challenge for computational neuroscience. Here, we investigate how internal representations from Whisper predict intracranial ECoG responses during naturalistic speech perception. We introduce a time-resolved neural encoder that combines speech embeddings with a recurrent temporal model and soft attention, allowing us to examine layer-wise brain alignment. Intermediate Whisper layers provide the strongest correspondence with neural activity, supporting a hierarchical match between model representations and cortical speech processing. Comparisons with baselines show that high-resolution ECoG responses benefit from temporally structured modelling beyond linear mappings from the same speech representations. In addition, attention maps reveal temporally local alignment between speech embeddings and neural responses, while a phonemic interpretability analysis identifies anatomically coherent phoneme-category organization among encoding-informative electrodes. Together, these results suggest that speech foundation models offer a useful framework for studying time-resolved cortical speech representations.

2606.02299 2026-06-02 math.CA

Sharp sign uncertainty for trigonometric polynomials

三角多项式的尖锐符号不确定性

Tolibjon Ismoilov

AI总结 研究单位圆上关于对称Borel测度的三角多项式的符号不确定性,确定了具有非正μ积分的三角多项式最后符号变化的最小半径,并推广到高维球面上的极测度及[0,1]上的多项式模拟。

Comments 27 pages, 1 figure

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AI中文摘要

我们研究了关于单位圆 $\mathbb{R}/\mathbb{Z}$ 上对称 Borel 测度 $\mu$ 的指定次数 $N$ 的三角多项式的符号不确定性原理。对于每个这样的测度,我们确定了具有非正 $\mu$ 积分的三角多项式最后符号变化的最小半径。我们进一步将这些结果推广到高维球面 $\mathbb{S}^d$ 上的极测度,表明极值问题通过测度的极部分简化为一维情形,并利用实直线上的正交多项式在 $[0,1]$ 上建立了多项式模拟。

英文摘要

We study sign uncertainty principles for trigonometric polynomials of prescribed degree $N$ with respect to a symmetric Borel measure $μ$ on the unit circle $\mathbb{R}/\mathbb{Z}$. For each such measure, we determine the smallest radius of the last sign change for trigonometric polynomials with non-positive $μ$-integral. We further extend these results to polar measures on higher-dimensional spheres $\mathbb{S}^d$, showing that the extremal problem reduces to the one-dimensional case via the polar part of the measure, and we establish a polynomial analogue on $[0,1]$ using orthogonal polynomials on the real line.

2606.02298 2026-06-02 cond-mat.mtrl-sci

Room-Temperature Electric-Field Control of Anomalous Hall Effect in Py/BTO/LSMO Heterostructures

Py/BTO/LSMO异质结构中反常霍尔效应的室温电场调控

Kusampal Yadav, Kousik Das, Aditya Raj, Mainak Ghosh, Abhishek Kumar, Kartick Biswas, Kalyan Sarkar, Pavan Nukala, Sayantika Bhowal, Devajyoti Mukherjee

AI总结 本研究通过外延生长Py/BTO/LSMO异质结构,利用衬底诱导应变和铁电极化,实现了室温下反常霍尔效应的电场调控,调制幅度高达93%,为低功耗自旋电子器件提供了新途径。

Comments Submitted to Advanced Functional Materials. This manuscript is a preprint and has not yet undergone peer review. Sayantika Bhowal (2) and Devajyoti Mukherjee (1) are corresponding authors

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AI中文摘要

我们展示了在MgO和LaAlO3衬底上外延生长的Ni80Fe20 (Py)/BaTiO3 (BTO)/La0.7Sr0.3MnO3 (LSMO)薄膜异质结构中,反常霍尔效应的室温电场调控。衬底诱导的应变状态产生不同的磁各向异性,实现了反常和拓扑霍尔贡献之间的电压驱动调谐。压电力显微镜证实了BTO中稳健的铁电极化,该极化与界面轨道重构和载流子再分布强耦合。结果,霍尔电阻率表现出巨大的低电压可调性,在仅0.5 V和2 V的工作电压下调制幅度高达近93%。密度泛函理论计算进一步揭示了极化控制的Rashba自旋分裂,建立了铁电序与涌现量子输运之间的直接联系。这些发现确立了Py/BTO/LSMO异质结构作为低功耗多功能自旋电子器件的有前途候选者,其中衬底工程能够控制涌现的量子输运现象。

英文摘要

We demonstrate room temperature electric field control of the anomalous Hall effect in epitaxial Ni80Fe20 (Py) BaTiO3 (BTO) La0.7Sr0.3MnO3 (LSMO) thin film heterostructures grown on MgO and LaAlO3 substrates. Substrate induced strain states generate distinct magnetic anisotropies, enabling voltage driven tuning between anomalous and topological Hall contributions. Robust ferroelectric polarization in BTO, confirmed by piezoresponse force microscopy, couples strongly to interfacial orbital reconstruction and carrier redistribution. As a result, Hall resistivity exhibits giant low voltage tunability, with up to nearly 93 percent modulation at operating voltages of only 0.5 tand 2 V. Density functional theory calculations further reveal polarization controlled Rashba spin splitting, establishing a direct link between ferroelectric order and emergent quantum transport. These findings establish Py/BTO/LSMO heterostructures as promising candidates for low-power multifunctional spintronic devices, where substrate engineering enables control over emergent quantum transport phenomena.