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2605.28469 2026-05-28 cond-mat.quant-gas

Wetting of quantum fluids: a route to free-standing shell-shaped quantum droplets

量子流体的浸润:通向自由站立壳状量子液滴的途径

Francesco Ancilotto

AI总结 研究三组分玻色混合物中自束缚量子流体间的浸润现象,通过调节散射长度实现从部分浸润到完全浸润的转变,并形成自由站立的核壳液滴,支持量子化涡旋激发。

Comments 10 pages, 9 figures

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AI中文摘要

我们研究了由$^{23}$Na、$^{39}$K和$^{41}$K原子组成的三组分玻色混合物中自束缚量子流体间的浸润现象。在包含平均场相互作用和李-黄-杨量子涨落修正的密度泛函方法中,我们考虑由组分$(1,2)$和$(2,3)$形成的两种二元量子液体,并研究较软的$(1,2)$液体在较硬的$(2,3)$基底上的吸附。通过调节种间散射长度$a_{12}$,我们展示了$(1,2)$液体的表面张力可以强烈变化,驱动从部分浸润到完全浸润$(2,3)$相的转变。从圆柱帽几何形状提取的接触角随$a_{12}$增加而连续减小,并在临界值$a_{12}^{c}= -42\,a_0$附近消失。在完全浸润区域,有限量的$(1,2)$液体包裹在球形$(2,3)$液滴周围,产生一个无需外部约束的自束缚核壳液滴,其组分1密度具有壳状中空投影。我们进一步展示了这种壳状量子液滴可以维持量子化的涡旋激发。这些结果确定了浸润是工程化自由站立壳状量子液体的一种途径,并为研究多组分量子液滴中的毛细现象、拓扑和超流性提供了新可能性。

英文摘要

We investigate wetting phenomena between self-bound quantum fluids in a three-component Bose mixture of $^{23}$Na, $^{39}$K, and $^{41}$K atoms. Within a density-functional approach including mean-field interactions and Lee-Huang-Yang quantum-fluctuation corrections, we consider two binary quantum liquids, formed by components $(1,2)$ and $(2,3)$, and study the adsorption of the softer $(1,2)$ liquid on a stiffer $(2,3)$ substrate. By tuning the interspecies scattering length $a_{12}$, we show that the surface tension of the $(1,2)$ liquid can be strongly varied, driving a transition from partial wetting to complete wetting of the $(2,3)$ phase. The contact angle extracted from cylindrical-cap geometries decreases continuously with increasing $a_{12}$ and vanishes near a critical value $a_{12}^{c}= -42\,a_0$. In the complete-wetting regime, a finite amount of $(1,2)$ liquid wraps around a spherical $(2,3)$ droplet, producing a self-bound core-shell droplet without external confinement, whose component-1 density has a shell-like, hollow projection. We further show that such shell-shaped quantum droplets can sustain quantized vortical excitations. These results identify wetting as a route to engineering free-standing shell-shaped quantum liquids and suggest new possibilities for studying capillarity, topology, and superfluidity in multicomponent quantum droplets.

2605.28466 2026-05-28 math.FA

On a problem of Johnson and Wolfe

关于Johnson和Wolfe的一个问题

Manuel Maestre, Domingo García, Daniel L. Rodríguez-Vidanes

AI总结 本文通过测度论相位校正方法,证明了在复C(K)空间中范数达到算子的稠密性,解决了Johnson和Wolfe在1979年提出的复情形公开问题。

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AI中文摘要

1979年,Johnson和Wolfe证明了在实情形下,当K和S是紧Hausdorff空间时,范数达到算子在L(C(K),C(S))中稠密。相应的复情形自那时起一直未解决,主要是因为实证明依赖于序和符号分解论证,而这些对于复测度不再适用。本文解决了复情形。我们证明,对于任意紧Hausdorff空间K和S,从复空间C(K)到赋有上确界范数的复空间C(S)的范数达到算子集合在L(C(K),C(S))中稠密。证明用基于极分解、单模逼近和加权全变差半连续原理的测度论相位校正论证取代了实序理论机制。这产生了一个复缺陷约化过程,恢复了复C(K)-空间中Johnson-Wolfe密度定理的完全一般性。

英文摘要

In 1979, Johnson and Wolfe proved that norm-attaining operators are dense in $L(C(K),C(S))$ when $K$ and $S$ are compact Hausdorff spaces in the real setting. The corresponding complex case has remained open since then, mainly because the real proof relies on order and sign-decomposition arguments that are no longer available for complex measures. In this paper, we settle the complex case. We prove that, for arbitrary compact Hausdorff spaces $K$ and $S$, the set of norm-attaining operators from the complex space $C(K)$ into the complex space $C(S)$ endowed with the supremum norm is dense in $L(C(K),C(S))$. The proof replaces the real order-theoretic mechanism by a measure-theoretic phase-correction argument, based on polar decompositions, unimodular approximation, and a semicontinuity principle for weighted total variation. This yields a complex defect-reduction procedure which recovers the Johnson-Wolfe density theorem in full generality for complex $C(K)$-spaces.

2605.28463 2026-05-28 cond-mat.mes-hall physics.optics

Substrate-driven topological engineering in plasmonic Su-Schrieffer-Heeger chains

等离子体Su-Schrieffer-Heeger链中的衬底驱动拓扑工程

Florian Herz, Alireza Naeimi, Svend-Age Biehs

AI总结 通过等离子体SSH链与电磁环境的相互作用,利用长程和短程衬底耦合实现拓扑带结构工程,诱导拓扑保护边缘态。

Comments 12 pages, 14 figures

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AI中文摘要

我们展示了通过等离子体Su-Schrieffer-Heeger(SSH)链与其电磁环境相互作用来工程化其拓扑能带结构的可能性。我们发现,SSH链的面内模式与平面衬底的表面等离激元之间的长程相互作用引入了与Zak相位变化相关的能带杂化。另一方面,与衬底的短程相互作用引入了能带接触,同样伴随着Zak相位的变化。令人惊讶的是,第二种机制使得在孤立等离子体SSH链对应拓扑平凡相的参数下,能够出现拓扑保护的边缘态。我们通过改变链-衬底距离和二聚化参数来研究这些机制。最后,我们讨论了抗无序的鲁棒性,并以一个例子说明了所观察到的效应对沿链的近场辐射热传递的影响。我们的发现为通过耦合到等离子体环境来工程化等离子体拓扑构型中的边缘态铺平了道路。

英文摘要

We demonstrate the possibility of engineering the topological band structure of a plasmonic Su-Schrieffer-Heeger (SSH) chain through the interaction with its electromagnetic environment. We find that the long-range interaction of the in-plane modes of the SSH chain with the surface plasmon polaritons of a planar substrate introduces a band hybridization connected to a change of the Zak phase. On the other hand, the short-range interaction with the substrate introduces a band touching, again with a change in the Zak phase. Surprisingly, this second mechanism enables the emergence of topologically protected edge modes for parameters which correspond to the topologically trivial phase for an isolated plasmonic SSH chain. We study these mechanisms by changing the chain-substrate distance and the dimerization parameter. Finally, we discuss the robustness against disorder and, as one example, the impact of the observed effects on the near-field radiative heat transfer along the chain. Our findings pave the way to the engineering of edge modes in plasmonic topological configurations via the coupling to a plasmonic environment.

2605.28461 2026-05-28 math.KT

On presentations of K-groups by generators and relations

关于K群由生成元和关系表示的注记

Bernhard Köck

AI总结 本文推广了Kasprowski、Winges和作者的工作,证明有界大小的多复形足以生成高阶K群,并给出了相应的关系;同时报告了代数证明Quillen的dévissage同构对于K_1满射的进展,并给出了一个需要更复杂方法的简单例子。

Comments 13 pages; to appear in a conference volume published by Springer in the series: Proceedings in Mathematics and Statistics

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AI中文摘要

在Grayson对高阶K群的组合描述中,生成元是任意大小的有界无环二元多复形。推广Kasprowski、Winges和作者的工作,我们在本文中证明有界大小的多复形就足够了,并提供了相应的关系。此外,我们报告了在代数证明Quillen的dévissage同构对于K_1满射的尝试中的进展,并给出了一个在余域中看似需要更复杂方法的初等且相当简单的例子。

英文摘要

In Grayson's combinatorial description of higher K-groups, the generators are bounded acyclic binary multi-complexes of arbitrary size. Generalising work by Kasprowski, Winges and the author, we show in this paper that multi-complexes of bounded size suffice and we provide the corresponding relations. Furthermore, we report on the progress in our attempt to algebraically prove the surjectivity of Quillen's dévissage isomorphism for K_1 and we give an elementary and fairly simple example in the codomain which appears to require a more sophisticated approach.

2605.28460 2026-05-28 cs.IT math.AG math.IT

Locally recoverable codes from elliptic surfaces with availability and hierarchical locality

来自椭圆曲面的具有可用性和分层局部性的局部可恢复码

Elena Berardini, Andrea Fornetto

AI总结 利用椭圆曲线的挠群和椭圆曲面的纤维结构,构造了具有可用性t>2、分层局部性以及两者结合的局部可恢复码。

Comments 27 pages, comments are welcome

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AI中文摘要

本文提出了几种从椭圆曲面构造局部可恢复码的方法。特别地,我们能够获得可用性$t>2$的码、具有分层局部性的码,以及结合了可用性和分层局部性的码。我们的构造依赖于椭圆曲线的挠群性质和椭圆曲面的纤维结构。具体地,利用曲面的几何引入多维设置,允许更多的恢复集,最终形成嵌套结构。

英文摘要

In this paper, we propose several constructions of Locally Recoverable Codes from elliptic surfaces. In particular, we are able to obtain codes with availability $t>2$, codes with hierarchical locality and, finally, codes which combine availability and hierarchical locality. Our constructions rely on the properties of the torsion groups of elliptic curves and on the fibered structure of elliptic surfaces. In particular, the geometry of the surface is used to introduce a multi-dimensional setting, allowing for more recovery sets, eventually nested one within another.

2605.28458 2026-05-28 physics.optics

Simultaneous Measurement of Circular Dichroism and Circular Differential Scattering

圆二色性与圆差分散射的同时测量

Qiang Hao, Pathum Wathudura, Huy Pham, In Han Ha, Abrahan Martinez, Justin Lovett, Nicholas C. Fitzkee, Ki Tae Nam, Shengli Zou, Dongmao Zhang

AI总结 本文开发了一种双通道光谱仪,通过散射光谱匹配方法实现同一溶液中圆二色性(CD)和圆差分散射(CDS)光谱的同时获取,并首次实验展示了两种光谱的同步采集。

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AI中文摘要

手性光谱学通过圆偏振光的相互作用,提供了一种非侵入性、无标记的方法来解析微观结构细节。尽管手性材料表征中广泛应用且提供互补信息,但圆二色性(CD)和圆差分散射(CDS)光谱的同时获取仍然具有挑战性。在这项工作中,我们开发了一种双通道光谱仪,能够从同一溶液中获取CD和CDS光谱。为了解决CDS基线校正的难题,我们引入了一种散射光谱匹配方法。使用两种代表性模型系统验证了仪器的性能:d-10樟脑磺酸铵和聚苯乙烯纳米颗粒(PSNPs)的混合物,以及同时表现出手性吸收和散射的等离子体金螺旋纳米颗粒。对于前者,由于PSNPs是非手性散射颗粒且CDS光谱受手性吸收影响,CDS光谱与CD光谱符号相反。对于后者,CD和CDS光谱均表现出匹配的共振波长和对右旋圆偏振光的更强响应,表明手性吸收和散射源于相同的等离子体共振模式。据我们所知,这项工作首次实验展示了系综平均CD和CDS光谱的同时获取。所提出的技术能够在相同条件下直接且准确地比较CD和CDS光谱。

英文摘要

Chiroptical spectroscopy provides a non-invasive, label-free approach for resolving microscopic structural details via interactions with circularly polarized light. Despite the widespread application and complementary information provided for chiroptical materials characterization, the simultaneous acquisition of circular dichroism (CD) and circular differential scattering (CDS) spectra has remained challenging. In this work, we develop a dual-channel spectrometer that enables the acquisition of CD and CDS spectra from the same solution. To address the challenge of CDS baseline correction, we introduce a scattering spectral matching method. The performance of the instrument is validated using two representative model systems: a mixture of ammonium d-10 camphor sulfonate and polystyrene nanoparticles (PSNPs), and plasmonic gold helicoid nanoparticles, which exhibit both chiral absorption and scattering. For the former case, the CDS spectra show opposite signs to the CD spectra because the PSNPs are achiral scattering particles and the CDS spectra are affected by the chiral absorption. For the latter case, both CD and CDS spectra exhibit matched resonance wavelengths and stronger responses to the right-handed circularly polarized light, indicating that the chiral absorption and scattering arise from the same plasmonic resonance modes. To the best of our knowledge, this work represents the first experimental demonstration of the concurrent acquisition of ensemble-averaged CD and CDS spectra. The presented technique enables a direct and accurate comparison of CD and CDS spectra acquired under identical conditions.

2605.28457 2026-05-28 astro-ph.IM

Noise Suppression and Radio Frequency Interference Rejection for Self-Triggered Radio Detectors of Extensive Air Showers

广延大气簇射自触发无线电探测器的噪声抑制与射频干扰抑制

Pengfei Zhang, Xin Xu, Hanrui Wang, Xing Xu, Bohao Duan, Feng Wei, Hongwei Pan, Xishui Tian, Yi Zhang, Pengxiong Ma, Olivier Martineau-Huynh

AI总结 针对自触发无线电探测器在真实射频干扰环境下灵敏度受限的问题,提出一种系统级设计方法,通过银河噪声建模、射频链路噪声预算、电磁兼容性缓解和测量验证,实现接近银河噪声极限的运行,并区分大气簇射信号与人为干扰。

Comments Accepted version; 21 pages, 20 figures

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Journal ref
IEEE Transactions on Instrumentation and Measurement, vol. 75, pp. 1-19, 2026, Art. no. 8003019
AI中文摘要

超高通量宇宙射线和中微子的自触发无线电探测为下一代天体粒子观测站提供了一种可扩展且经济高效的方法,但在实际射频干扰条件下仍面临挑战。在经典的大气簇射无线电波段,可达到的灵敏度和触发可靠性受到外部天空背景噪声与内部探测器单元噪声之间的平衡以及非平稳人为干扰的严重限制。在这项工作中,我们展示了一种自触发无线电探测器单元的端到端设计和实验特性,该单元明确优化为在银河噪声主导的区域内运行。我们不是专注于单个硬件组件或触发算法,而是采用一种系统级方法,将天空噪声建模、射频链路噪声预算、电磁兼容性缓解和测量驱动验证连贯地整合在一起。通过使用银河无线电背景作为定量参考,我们评估了探测器单元的内部噪声性能,并展示了在系统响应水平上区分广延大气簇射无线电信号与人为干扰的条件。我们进一步引入了一种间接噪声量化方法,基于在ADC级别评估的差分内部噪声测量,来估计完整射频链中低噪声放大器的贡献。所提出的探测器单元通过实验室和现场测量进行了验证,展示了在核心频段接近银河噪声极限的运行。这些结果为设计和部署大规模自触发无线电阵列(如GRAND)提供了一种实用且可转移的方法论。

英文摘要

Self-triggered radio detection of ultra-high-energy cosmic rays and neutrinos offers a scalable and cost-effective approach for next-generation astroparticle observatories, but remains challenging under realistic radio-frequency interference (RFI) conditions. In the classical air-shower radio band, the achievable sensitivity and trigger reliability are critically limited by the balance between external sky background noise and internal detector-unit noise, as well as by non-stationary anthropogenic interference. In this work, we present an end-to-end design and experimental characterization of a self-triggered radio detector unit explicitly optimized to operate in a galactic-noise-dominated regime. Rather than focusing on a single hardware component or trigger algorithm, we adopt a system-level methodology that coherently integrates sky-noise modeling, RF-chain noise budgeting, electromagnetic compatibility (EMC) mitigation, and measurement-driven validation. By using the galactic radio background as a quantitative reference, we assess the internal noise performance of the detector unit and demonstrate conditions under which extensive air shower (EAS) radio signals can be distinguished from anthropogenic interference at the system-response level. We further introduce an indirect noise-quantification method to estimate the low-noise amplifier contribution within the complete RF chain based on differential internal-noise measurements evaluated at the ADC level. The proposed detector unit is validated through laboratory and on-site measurements, demonstrating operation close to the galactic-noise limit in the core frequency band. These results provide a practical and transferable methodology for the design and deployment of large-scale self-triggered radio arrays such as GRAND.

2605.28455 2026-05-28 math.PR math.OC

Convergence Rate Analysis of Ratio Consensus Algorithms with Column-Allowable Matrices

列允许矩阵下比率共识算法的收敛速率分析

Balázs Gerencsér, Levente Szemerédi

AI总结 通过允许辅助节点无限频繁地取零值,改进了比率共识算法在增广网络上的几乎必然收敛速率界,适用于更广泛的算法族。

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AI中文摘要

当协议可以重新表述为在可能更大的增广网络上对向量值进行线性更新时,我们给出了比率共识算法的几乎必然收敛速率界。这是对Gerencsér和Gerencsér在2021年结果的改进,通过允许辅助节点无限频繁地取零值,使得该技术适用于更广泛的算法族。

英文摘要

We give almost sure convergence rate bounds of ratio consensus algorithms when the protocol can be reformulated to be linear updates of vector values on a possibly larger, augmented network. This is an improvement of the results of Gerencsér and Gerencsér from 2021 by allowing zero values on auxiliary nodes infinitely often which makes the technique applicable to a much larger family of algorithms.

2605.28453 2026-05-28 eess.SP

A Unified Framework for Unbiased Non-Coherent Over-the-Air Computation

无偏非相干空中计算的统一框架

Martin Dahl, Zheng Chen, Erik G. Larsson

AI总结 针对非相干空中计算(NC-OAC),提出一个包含数据-码字映射的三步框架,研究两种信道幅度知识下的无偏估计,并比较两种仿射映射,证明增强仿射映射的估计方差低一个数量级,同时提出性能更优的新映射。

Comments Accepted to IEEE Transactions on Communications

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AI中文摘要

空中计算(OAC)通过利用无线多址信道的叠加特性,在大规模分布式系统中实现高效数据聚合。与大多数现有假设精确信道状态信息的OAC研究不同,我们考虑非相干OAC(NC-OAC),其中发射机未知信道相位。提出了一个包含源数据与码字映射的NC-OAC三步框架:1)设备将其数据编码为非负码字;2)设备发送幅度与码字成比例的符号序列,使得接收机能够估计码字和。在全局信道幅度知识(统计或瞬时)两种场景下研究码字和的估计;3)接收机将估计的码字和解码为所需的源数据和。利用所提框架,我们首先研究NC-OAC的先前工作并将其映射到该框架。接着,定义并比较NC-OAC中最常用的两种(通常隐含的)映射:仿射映射和增强仿射映射。在无偏估计约束下,我们证明对于均匀分布的数据和标准信道假设,增强仿射映射在统计和瞬时信道知识下均表现出比仿射映射低一个数量级的估计方差。该结果通过大量仿真得到验证。最后,我们提出并分析一种新映射,其性能优于前两种仿射映射。

英文摘要

Over-the-Air Computation (OAC) enables efficient data aggregation in large-scale distributed systems by exploiting the superposition property of wireless multiple-access channels. In contrast to most existing studies on OAC assuming exact channel state information, we consider non-coherent OAC (NC-OAC) where the channel phase is unknown at the transmitters. A three-step framework for NC-OAC with a mapping between source data and codewords is proposed: 1) Devices encode their data to non-negative codewords; 2) Devices transmit a sequence of symbols with amplitude proportional to their codewords, such that the receiver can estimate the codeword sum. Estimation of the codeword sum is studied under two scenarios of global channel amplitude knowledge: statistical or instantaneous; 3) The estimated codeword sum is decoded to the desired source data sum at the receiver. With the proposed framework, we first study prior work on NC-OAC and map these to the framework. Next, we define and compare the two most commonly (often implicitly) used mappings for NC-OAC: the Affine and the Augmented Affine mappings. Under the constraint of unbiased estimation, we show that with uniformly distributed data and standard channel assumptions, the Augmented Affine mapping exhibits an order of magnitude lower estimation variance than the Affine mapping with both statistical and instantaneous channel knowledge. This result is validated by extensive simulations. Finally, we propose and analyze a new mapping, which demonstrates superior performance over the previous two affine mappings.

2605.28452 2026-05-28 math.NA cs.NA

Physics-constrained identification of graph-based thermal networks for spacecraft digital twins

基于物理约束的航天器数字孪生图热网络辨识

Luca Sosta, Carlo Ciancarelli, Leonardo Marini, Stefano Pagani, Francesco Regazzoni, Nicola Parolini

AI总结 提出一种物理约束的集总参数热模型标定框架,通过轨迹匹配从稀疏温度测量中重建热动力学,无需先验参数,确保物理可容许性,实现长期稳定预测。

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AI中文摘要

从稀疏和局部温度测量中重建能够有效模拟航天器行为的热模型仍然是一项具有挑战性的任务。为此,我们引入了一个物理约束的集总参数热模型(LPTMs)标定框架,该框架被表述为图动力系统的轨迹逆问题。该模型直接从温度测量和已知输入重建热动力学,而不依赖于从材料属性或几何假设导出的先验参数值。物理可容许性在参数化层面得到强制执行:节点系数的正性和导电相互作用的对称性通过构造施加。这保证了稳定的动力学,并将辨识问题限制在物理有意义的参数空间内,改善了条件性,无需额外的正则化。通过轨迹匹配解决辨识问题,确保在长时间范围内稳定展开。该方法在由高保真有限元模拟生成的合成数据集上进行了验证,这些数据集在逐渐复杂的强迫条件下生成。标定后的LPTM准确再现了长期温度演变,并对测量噪声表现出鲁棒性。所提出的框架通过将物理结构与数据驱动辨识相结合,为降阶热模型的标定提供了一种系统方法。数值结果表明了精度和计算效率之间的良好平衡,使模型适用于集成到航天器热数字孪生应用中。

英文摘要

Reconstructing a thermal model capable of efficiently simulating the behavior of a spacecraft from sparse and localized temperature measurements remains a challenging task. To address this, we introduce a physically-constrained calibration framework for Lumped Parameter Thermal Models (LPTMs), formulated as a trajectory-based inverse problem for graph dynamical systems. The model reconstructs thermal dynamics directly from temperature measurements and known inputs, without relying on a priori parameter values derived from material properties or geometric assumptions. Physical admissibility is enforced at the parameterization level: positivity of nodal coefficients and symmetry of conductive interactions are imposed by construction. This guarantees stable dynamics and restricts the identification problem to a physically meaningful parameter space, improving conditioning without the need of additional regularization. The identification problem is addressed through trajectory matching, ensuring stable rollout over extended time horizons. The methodology is validated on synthetic datasets generated from high-fidelity finite element simulations under progressively complex forcing conditions. The calibrated LPTMs accurately reproduce long-term temperature evolution and exhibit robustness to measurement noise. The proposed framework provides a systematic approach to the calibration of reduced-order thermal models by combining physical structure with data-driven identification. The numerical results show a favorable balance between accuracy and computational efficiency, making the models suitable for integration in spacecraft thermal Digital Twin applications.

2605.28451 2026-05-28 cs.PF cs.AR

Range, Not Precision: Block-Floating-Point Half-Precision FFT and SAR Imaging on Apple Silicon

范围,而非精度:Apple Silicon上的块浮点半精度FFT与SAR成像

Mohamed Amine Bergach

AI总结 针对半精度FFT在雷达信号处理中因动态范围不足导致溢出的问题,提出固定移位块浮点调度方案,在Apple M1上实现首个保质的FP16 SAR流水线,性能提升2.2倍。

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AI中文摘要

半精度(FP16)有望使GPU上的FFT吞吐量翻倍,但普遍观点认为其10位尾数不适合雷达级信号处理。我们证明这种看法在Apple Silicon上是错误的:FFT和合成孔径雷达(SAR)的约束不是尾数精度,而是5位指数的动态范围。我们首先测量到FP16 FFT的量化信噪比(SQNR)受限于56–61 dB——舒适地适用于雷达——然而,一个朴素的FP16 SAR流水线仅产生NaN,因为共轭-FFT-共轭逆变换使幅度增长N倍,且匹配滤波乘积(N=4096时约5×10^6)溢出FP16的65,504上限。我们通过固定移位块浮点(BFP)调度解决此问题:在每次逆变换前应用单个1/N缩放,将每个中间值限制在4096以下。级联随之而来:距离压缩输出变为O(1)而非O(N),进而使下游方位FFT输出保持FP16可加载,而非在O(N^2)处溢出。结果是首个保质的FP16 SAR流水线:峰值/积分旁瓣比、目标SNR和分辨率与FP32参考匹配,误差在0.1 dB以内,端到端SQNR为42 dB,而基8 FP16 FFT在无风扇Apple M1上达到306 GFLOPS——是139 GFLOPS FP32基线的2.2倍。最后,我们测量到FP8(E4M3/E5M2)的SQNR降至14–20 dB,使FP16成为当今基于FFT的雷达的精度下限——未来的精度恢复方法可能进一步降低该下限——并表明此处低精度的杠杆是范围管理,而非尾数位数。

英文摘要

Half precision (FP16) promises to double FFT throughput on GPUs, but the prevailing view is that its 10-bit mantissa makes it unsuitable for radar-grade signal processing. We show this framing is wrong on Apple Silicon: the binding constraint for FFT and Synthetic Aperture Radar (SAR) is not mantissa \emph{precision} but the 5-bit exponent's \emph{dynamic range}. We first measure that an FP16 FFT is mantissa-limited at 56--61~dB signal-to-quantization-noise ratio (SQNR) -- comfortably radar-usable -- yet a naïve FP16 SAR pipeline produces \emph{only} \texttt{NaN}, because the conjugate--FFT--conjugate inverse transform grows magnitudes by a factor of $N$, and the matched-filter product ($\sim\!5\times10^6$ at $N\!=\!4096$) overflows FP16's 65{,}504 ceiling. We resolve this with a fixed-shift \emph{block-floating-point} (BFP) schedule: a single $1/N$ scale applied before each inverse transform bounds every intermediate below 4096. A cascade follows: range-compression output becomes $O(1)$ instead of $O(N)$, which in turn keeps the downstream azimuth-FFT output FP16-loadable instead of overflowing at $O(N^2)$. The result is the first quality-preserving FP16 SAR pipeline: peak/integrated sidelobe ratios, target SNR, and resolution match the FP32 reference to within $0.1$~dB at $42$~dB end-to-end SQNR, while a radix-8 FP16 FFT reaches 306~GFLOPS -- $2.2\times$ over the 139~GFLOPS FP32 baseline -- on a fanless Apple~M1. Finally, we measure that FP8 (E4M3/E5M2) collapses to 14--20~dB SQNR, making FP16 \emph{today's} precision floor for FFT-based radar -- one that future precision-recovery methods may yet lower -- and showing that the lever for low precision here is range management, not mantissa bits.

2605.28449 2026-05-28 math.NT

Additive Diophantine Equations involving S-Units, Factorials and Ternary Recurrences with repeated root

涉及S-单位、阶乘和重根三元递推的加法丢番图方程

Vikas Godara, Divyum Sharma

AI总结 研究Cullen数C_n=n2^n+1与阶乘及S-单位构成的加法丢番图方程,证明其最大素因子趋于无穷,并求解特定方程。

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AI中文摘要

令$C_n=n2^n+1$表示第$n$个Cullen数。近期有研究兴趣在于找出所有具有给定丢番图性质的Cullen数。我们证明,对于固定整数$k$和有界整数$a_1,\ldots,a_k$,$C_n-a_1m_1!-\cdots-a_km_k!$的最大素因子以有效方式趋于无穷。我们也对某些更一般的三元递推序列族证明了这一点。此外,我们求解了丢番图方程$$C_n = m_1! + m_2! + s,$$其中$s$是由素数$2,3,5,7$组成的正整数。

英文摘要

Let $C_n=n2^n+1$ denote the $n$th Cullen number. There has been recent interest in finding all Cullen numbers having a given Diophantine property. We prove that, for a fixed integer $k$ and bounded integers $a_1,\ldots,a_k$, the greatest prime divisor of $C_n-a_1m_1!-\cdots-a_km_k!$ tends to infinity, in an effective way. We prove this for some more general families of ternary recurrence sequences as well. We also solve the Diophantine equation $$C_n = m_1! + m_2! + s,$$ where $s$ is a positive integer composed of primes $2,3,5,7$.

2605.28447 2026-05-28 hep-lat hep-ph nucl-th

The origin of excited states of the $Λ$ baryon at the SU(3) point from Lattice QCD

格点QCD中SU(3)对称点处Λ重子激发态的起源

Javier Suarez Sucunza, Thomas Luu, Maxim Mai, Ferenc Pittler, Carsten Urbach, Haobo Yan

AI总结 通过格点QCD计算SU(3)对称点处介子-重子单态和八重态不可约表示中的有限体积谱,结合UCHPT重拟合识别Λ(1405)为低八重态、Λ(1380)为单态束缚态,并定性识别Λ(1670)为重八重态束缚态。

Comments 14 pages, 10 figures

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AI中文摘要

在这项工作中,我们在味对称SU(3)点处确定了介子-重子单态和八重态不可约表示中的有限体积格点QCD谱。我们构造了合适的插值算符,并在相当大的体积(L=48)的系综上进行了计算。我们发现了三个阈值以下的能级,其中单态能量较低,两个八重态在1σ水平上非简并,对于这些大体积(M_πL≈14.5),这强烈表明在每个不可约表示中接近该能量存在一个束缚态。我们将这个有限体积谱与通过Lüscher方法的UCHPT预测进行比较,发现定性一致。最后,我们对UCHPT的自由参数进行了重新拟合,使用了可用的(实验和格点)数据,包括本工作中计算的能级。这使我们能够将极点轨迹追踪到物理点,将Λ(1405)识别为低八重态,将Λ(1380)识别为SU(3)极限下的单态束缚态。此外,Λ(1670)在定性水平上被识别为较重的八重态束缚态,并讨论了其与三体末态的关系。

英文摘要

In this work we determine the finite-volume lattice QCD spectrum at the flavor symmetric $\mathrm{SU}(3)$ point in the meson-baryon singlet and octet irreducible representations. We construct the appropriate interpolation operators and perform the calculation on ensembles in quite large volume ($L=48$). We find three below-threshold energy levels, with the singlet having lower energy and the two octets being non-degenerate at one sigma, which for these large volumes ($M_π L\approx 14.5$) strongly suggests a bound state close to that energy at each of the irreducible representations. We confront this finite-volume spectrum with the prediction from UCHPT through the Lüscher method finding qualitative agreement. Finally we perform a re-fit of UCHPT free parameters to the available (experimental and lattice) data including the energy levels calculated in this work. This allows us to follow the pole trajectories to the physical point, identifying the $Λ(1405)$ as a lower octet, and $Λ(1380)$ as a singlet bound state in the $\mathrm{SU(3)}$ limit. Furthermore, $Λ(1670)$ is identified on a qualitative level as the heavier octet bound state and its relation to three-body final states is discussed.

2605.28446 2026-05-28 cs.CE

Modelling the effect of fiber distribution on the transverse mechanical characteristics of unidirectionally reinforced continuous-fiber composite

纤维分布对单向增强连续纤维复合材料横向力学特性的影响建模

Sergejs Tarasovs, Janis Modniks, Andrea Bercini Martins, Christina Scheffler, Janis Andersons

AI总结 通过膨胀随机迁移算法生成不同纤维排列的代表性体积单元,结合有限元均匀化与多种描述符,发现纤维聚集显著提高横向刚度但降低强度,且平均最近邻距离可有效表征随机分布并线性关联力学性能。

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AI中文摘要

本研究探讨了纤维空间分布对单向增强连续纤维复合材料横向力学性能的影响。采用膨胀随机迁移算法生成具有受控纤维排列(从聚集到平衡构型)的代表性体积单元。使用周期性边界条件的有限元均匀化来估计有效弹性性能。为了表征纤维随机性并评估与实验微观结构的统计等效性,采用了多种描述符,包括最近邻距离、Ripley's K函数、对分布函数和局部纤维体积分数。结果表明,在恒定纤维体积分数下,与平衡分布相比,聚集纤维分布产生显著更高的横向刚度但更低的横向拉伸强度。对于玻璃/环氧复合材料,横向刚度根据纤维聚集程度变化高达20%。单个标量描述符——平均最近邻距离,被证明能有效表征足够随机的纤维分布:有效刚度随平均最近邻距离线性减小,而横向拉伸强度线性增加。这些发现突显了微观结构特征在定制复合材料性能中的关键作用,并为纤维增强材料的预测建模提供了稳健框架。

英文摘要

This study investigates the influence of fiber spatial distribution on the transverse mechanical properties of unidirectionally reinforced continuous-fiber composites. A Swelling & Random Migration algorithm was employed to generate representative volume elements with controlled fiber arrangements, ranging from clustered to equilibrium configurations. Finite element homogenization with periodic boundary conditions was used to estimate effective elastic properties. To characterize fiber randomness and assess statistical equivalence with experimental microstructures, several descriptors are employed, including nearest neighbor distance, Ripley's K-function, pair distribution function, and local fiber volume fraction. Results reveal that, at constant fiber volume fraction, clustered fiber distributions yield significantly higher transverse stiffness but lower transverse tensile strength compared to the equilibrium distributions. For glass/epoxy composites, transverse stiffness varies by up to 20% depending on the degree of fiber clustering. A single scalar descriptor, the mean nearest neighbor distance, was shown to efficiently characterize sufficiently random fiber distributions: effective stiffness decreases, whereas transverse tensile strength increases linearly with mean nearest neighbor distance. The findings highlight the critical role of microstructural characteristics in tailoring composite performance and provide a robust framework for predictive modeling of fiber reinforced materials.

2605.28445 2026-05-28 cond-mat.stat-mech

The Resetting Heat Engine: A Thermodynamic Cycle of Thermal Expansion and Compression

重置热机:热膨胀与压缩的热力学循环

Oded Farago

AI总结 本文通过分析受随机重置的布朗粒子,基于前向与反向轨迹集合的KL散度,将过程描述为热膨胀与压缩的热力学循环,并推导了熵产率与重置率的关系。

Comments 6 pages. One figure

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AI中文摘要

我们考虑一个受外部势约束且经历随机重置到原点的布朗粒子。受动力学重复性质的启发,我们将该过程描述为热膨胀与压缩的热力学循环,并通过基于前向与反向轨迹集合的Kullback-Leibler(KL)散度的框架进行分析。虽然熵产通常依赖于完整的轨迹集合且不能仅简化为热力学状态变量,但我们表明谐振子势是一个特例,其中熵产恰好简化为仅由重置前后分布决定的状态函数形式。对于周期性和泊松重置,推导了显式解析结果。在低重置率$r$下,熵产率随$r$线性增长,并与重置分布和平衡分布之间的对称KL散度成正比。在极高重置率下,重置过程变得几乎永久,熵产消失。非谐振四次势的Langevin模拟显示了相同的通用行为,表明这些特征不限于谐振子约束。我们的结果建立了随机重置、热力学循环和不可逆性的信息论度量之间的直接联系。

英文摘要

We consider a Brownian particle confined by an external potential and subject to stochastic resetting to the origin. Motivated by the repetitive nature of the dynamics, we describe the process as a thermodynamic cycle of thermal expansion and collapse, analyzed via a framework based on the Kullback-Leibler (KL) divergence between forward and reversed trajectory ensembles. While the entropy production generally depends on the full trajectory ensemble and cannot be reduced to thermodynamic state variables alone, we show that the harmonic potential constitute a special case, where the entropy production reduces exactly to a state-function-like expression determined solely by the distributions before and after resetting. Explicit analytical results are derived for periodic and Poissonian resetting. At low resetting rates $r$, the entropy production rate grows linearly with $r$ and is proportional to the symmetric KL divergence between the reset and equilibrium distributions. At very high rates, the resetting process becomes effectively perpetual and the entropy production vanishes. Langevin simulations for an anharmonic quartic potential display the same generic behavior, indicating that these features are not restricted to harmonic confinement. Our results establish a direct connection between stochastic resetting, thermodynamic cycles, and information-theoretic measures of irreversibility.

2605.28443 2026-05-28 math.AP

Towards a Fundamental Principle for $λ$-Homogeneous Solutions on Cones

锥上$λ$-齐次解的一个基本原理

Michael Tsopanopoulos

AI总结 本文针对开口尖凸锥上的常系数齐次方程组,通过引入Mellin型算子将Ehrenpreis-Palamodov理论中的解族$S_{\mathcal B}$推广为$S_{\mathcal B,λ}$,证明了$λ$-齐次解的一个弱基本原理。

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AI中文摘要

我们在开口尖凸锥上证明了齐次常系数方程组$λ$-齐次解的一个弱基本原理。从Ehrenpreis-Palamodov理论中出现的解族$S_{\mathcal B}$出发,通过将指数核$e^{\langle x,z\rangle}$替换为齐次核$(-\langle x,z\rangle)^λ$,构造了相应的族$S_{\mathcal B,λ}$。关键工具是Paley-Wiener空间上的Mellin型算子,它将经典理论与Euler约束设定联系起来。对于$λ\in \mathbb{C}\setminus \mathbb{N}_0$且在可见性假设下,我们证明了$S_{\mathcal B,λ}$的张成空间在$λ$-齐次解空间中是稠密的。

英文摘要

We prove a weak fundamental principle for $λ$-homogeneous solutions of homogeneous constant-coefficient systems on open pointed convex cones. Starting with the solution family $S_{\mathcal B}$ arising in the Ehrenpreis--Palamodov theory, we construct a corresponding family $S_{\mathcal B,λ}$ by replacing the exponential kernels $e^{\langle x,z\rangle}$ with homogeneous kernels $(-\langle x,z\rangle)^λ$. The key tool is a Mellin-type operator on Paley--Wiener spaces, which links the classical theory to the Euler-constrained setting. For $λ\in \mathbb{C}\setminus \mathbb{N}_0$ and under a visibility assumption, we show that the span of $S_{\mathcal B,λ}$ is dense in the space of $λ$-homogeneous solutions.

2605.28439 2026-05-28 quant-ph cs.ET

Compile-Time Simplification of Classically Controlled Operations in Dynamic Circuits

动态电路中经典控制操作的编译时简化

Innocenzo Fulginiti, Yanbin Chen, Christian B. Mendl, Helmut Seidl

AI总结 提出一种编译时优化框架,通过符号执行和概率电路模型,将动态电路中的经典控制操作转化为纯酉操作或概率组件,减少经典前馈延迟,实验实现约50%的经典前馈减少。

Comments Accepted at ISC High Performance 2026; to appear in the IEEE Xplore proceedings

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AI中文摘要

动态电路利用电路中测量的实时结果,由经典控制器处理,以在电路执行期间调整后续操作。这种相对于静态电路的额外灵活性是有代价的。电路中测量通常比酉门更慢且噪声更大。此外,经典前馈需要在量子处理器(QPU)和经典控制器之间交换信息,引入延迟,从而削弱动态电路的实际性能。我们提出了一种编译时优化框架,在保持动态电路语义的同时减少经典控制的使用。该框架的核心是通过静态分析,在传播经典信息的同时符号执行电路。通过将这种经典-量子信息与扩展了模拟经典前馈的概率控制的概率电路模型相结合,我们获得了动态电路的中间概率表示。在这种表示中,电路中测量和经典控制操作可以被移除或重写为纯酉操作和概率组件。与仅针对电路中测量的现有编译时优化相比,我们的方法适用于现代量子编程语言中可表达的更广泛的动态电路类别。我们在随机生成的动态电路上评估了我们的框架,实现了约50%的经典前馈减少,在有利设置下甚至更高。

英文摘要

Dynamic circuits use real-time outcomes of mid-circuit measurements, processed by a classical controller, to adapt subsequent operations during circuit execution. This additional flexibility over static circuits comes at a price. Mid-circuit measurements are typically slower and noisier than unitary gates. Furthermore, classical feedforward requires exchanging information between the quantum processor (QPU) and the classical controller, introducing latency that erodes the practical performance of dynamic circuits. We propose a compile-time optimization framework that reduces the use of classical controls in dynamic circuits while preserving their semantics. At its core, the framework uses a static analysis that symbolically executes the circuit by propagating classical information alongside the quantum state. By combining this classical-quantum information with the Probabilistic Circuit Model extended with probabilistic controls that emulate classical feedforward, we obtain an intermediate probabilistic representation of the dynamic circuit. In this representation, mid-circuit measurements and classically controlled operations can be removed or rewritten as purely unitary operations and probabilistic components. Compared to existing compile-time optimizations that target only mid-circuit measurements, our method applies to a broader class of dynamic circuits expressible in modern quantum programming languages. We evaluated our framework on randomly generated dynamic circuits, achieving about 50% classical feedforward reduction and even higher reductions in favorable settings.

2605.28437 2026-05-28 quant-ph nucl-th physics.ed-ph

Learning shape resonances from the stabilization method

从稳定化方法学习形状共振

Daniel Kromm, Hans-Werner Hammer, Artem Volosniev

AI总结 本文通过稳定化方法将连续谱离散化,利用两能级系统直观解释共振,并引入基于空间局域化的新方法提取共振参数。

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AI中文摘要

量子力学中的共振通常被引入为嵌入连续谱中的准束缚态,由于连续态具有抽象性质,这一视角在概念上可能具有挑战性。在本文中,我们讨论了一种替代方法,通过将问题表述为离散量子态来避免对连续谱的显式处理。我们的讨论基于稳定化方法,其中系统被限制在一个有限区域内,使得连续谱被离散能谱取代。然后,共振在改变约束箱尺寸时表现为能级中的特征特征,提供了基于两能级系统的直观解释,同时与标准量子力学课程紧密相连。我们回顾了该方法,推导了选定结果,并讨论了从稳定化图中提取共振参数的实际策略。除了已建立的拟合程序外,我们还引入了一种基于共振态空间局域化分析的新方法,能够稳健地识别共振性质。通过吸引和排斥的δ壳势(作为简单且具有启发性的模型系统,可进行解析处理)对该方法进行了说明。

英文摘要

Resonances in quantum mechanics are commonly introduced as quasi-bound states embedded in the continuum, a perspective that can be conceptually challenging due to the abstract nature of continuum states. In this work, we discuss an alternative approach that avoids an explicit treatment of the continuum by formulating the problem in terms of discrete quantum states. Our discussion is based on the stabilization method, in which the system is confined to a finite region such that the continuum is replaced by a discrete energy spectrum. Resonances then appear as characteristic features in the energy levels under variation of the confining box size, providing an intuitive interpretation in terms of a two-level system while remaining closely connected to standard quantum mechanics curriculum. We review the method, derive selected results, and discuss practical strategies for extracting resonance parameters from stabilization diagrams. In addition to established fitting procedures, we introduce a novel approach based on the analysis of spatial localization of resonant states, which enables a robust identification of resonance properties. The approach is illustrated using both attractive and repulsive delta-shell potentials, which serve as simple and instructive model systems amenable to analytical treatment.

2605.28436 2026-05-28 math.MG

Localization from Pseudoranges: Quadrics and Duality

从伪距定位:二次曲面与对偶性

Mireille Boutin, Gregor Kemper

AI总结 本文完整描述了全球定位问题的解,强调欠定情形,证明解构成二次曲面,并发现卫星位置也位于二次曲面上,两者具有显著的对偶性,适用于伪距多边定位等更广泛问题。

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AI中文摘要

本文完整描述了全球定位问题的解,强调欠定情形。我们证明解构成一个二次曲面,该曲面可能以各种方式退化。也许更令人惊讶的是,卫星位置也位于一个二次曲面上,并且这两个二次曲面表现出显著的对偶性:它们位于垂直的仿射空间上,但共享相同的对称轴。此外,一个二次曲面的顶点是另一个的焦点,反之亦然。本文的结果不仅适用于全球定位问题,还适用于更广泛的一类问题,即伪距多边定位。这包括一系列现实世界中的定位问题,其中信号在未知发射时间发射,并由已知位置的传感器接收。特别地,本文有助于在存在额外约束的情况下解决欠定多边定位问题。我们通过两个例子说明:定位地面上的清洁机器人和定位海洋上的筏子。

英文摘要

This paper gives a complete description of the solutions of the global positioning problem, emphasizing the under-determined case. We show that the solutions form a quadric, which may degenerate in various ways. Perhaps more surprisingly, the satellite positions also lie on a quadric, and these two quadrics exhibit a remarkable duality: They live on perpendicular affine spaces but share the same axis of symmetry. Moreover, the vertices of one quadric are the foci of the other and vice versa. The results of this paper are not only applicable to the global positioning problem, but to a wider class of problems known as pseudorange-multilateration. This includes a range of real-world localization problems where a signal is emitted at an unknown emission time, and received by sensors at known positions. In particular, the paper can be useful for solving an under-determined multilateration problem in the presence of additional constraints. We illustrate this with two examples: locating a cleaning robot on the ground and locating a raft on the ocean.

2605.28435 2026-05-28 math.AP

Quasineutral Plasmas and the Geometry of Kinetic Stability

准中性等离子体与动理学稳定性的几何结构

Mikaela Iacobelli

AI总结 本文从Vlasov-Poisson系统出发,概述准中性极限中的动理学不可压缩约束、快速振荡和奇异电场导致的稳定性问题,并引入适应相空间动力学的动理学Wasserstein距离以改进稳定性估计。

Comments 13 pages, 6 figures

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AI中文摘要

本文概述了等离子体模型中的准中性极限。从Vlasov-Poisson系统出发,解释了德拜长度的作用、动理学不可压缩约束的出现,以及由快速振荡和奇异电场引起的稳定性问题。一个中心主题是,动理学流的几何结构应反映在扰动的测量方式上。这导致了适应相空间动力学的动理学Wasserstein距离,为准中性极限提供了精细的稳定性估计。本文还讨论了具有热化电子的相关模型以及电磁Vlasov-Maxwell设定中的额外挑战。

英文摘要

This article presents an overview of quasineutral limits in plasma models. Starting from the Vlasov-Poisson system, it explains the role of the Debye length, the emergence of a kinetic incompressibility constraint, and the stability issues caused by fast oscillations and singular electric fields. A central theme is that the geometry of the kinetic flow should be reflected in the way perturbations are measured. This leads to kinetic Wasserstein distances adapted to phase-space dynamics, which provide refined stability estimates for quasineutral limits. The article also discusses related models with thermalized electrons and the additional challenges of the electromagnetic Vlasov-Maxwell setting.

2605.28434 2026-05-28 eess.SP

Experimental Characterization of a Multifunction X-Band AESA Radar Demonstrator

多功能X波段AESA雷达演示样机的实验表征

Francesco Mancuso, Giulio Meucci, Matteo Pardi, Giulio Giovannetti, Alberto Lupidi

AI总结 本文通过沿海现场实验,表征了一款紧凑型X波段有源电子扫描阵列(AESA)雷达演示样机在波达方向估计、自适应干扰抑制和高分辨率逆合成孔径雷达成像三种核心功能上的性能,验证了其适用于先进海上监视任务。

Comments 6 pages, 7 figures. Accepted for publication in the Proceedings of the 2026 IEEE Radar Conference (RadarConf26)

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AI中文摘要

现代海上监视需要能够在杂波和对抗环境中运行的多功能雷达系统。本文介绍了一款紧凑型X波段有源电子扫描阵列(AESA)雷达演示样机的实验表征。该系统在海军支援与实验中心(CSSN)及其专业机构G. Vallauri研究所的真实沿海现场环境中进行了评估,该机构在测试和评估运行中及开发中传感器的性能方面拥有历史专长,使用了真实海上目标和有源噪声干扰机。试验评估了三种核心功能:波达方向(DoA)估计、使用MVDR波束形成的自适应干扰抑制以及高分辨率逆合成孔径雷达(ISAR)成像。结果证实,该演示样机成功检测并定位目标,有效抑制高功率干扰,并生成非合作船只的清晰ISAR图像。这些发现验证了AESA演示样机的多功能性能,确认了其适用于先进海上监视应用。

英文摘要

Modern naval surveillance demands multifunction radar systems capable of operating in cluttered and contested environments. This paper presents the experimental characterization of a compact, X-band Active Electronically Scanned Array (AESA) radar demonstrator. The system was evaluated in a realistic coastal field environment at Naval Support and Experimentation Centre (CSSN) and, specifically, its specialized institute, the G. Vallauri Institute, which has historical expertise in testing and evaluating the performance of operational sensors as well as those under development, using real maritime targets and an active noise jammer. The trials assessed three core functions: direction-of-arrival (DoA) estimation, adaptive jammer suppression using MVDR beamforming, and high-resolution Inverse Synthetic Aperture Radar (ISAR) imaging. The results confirm that the demonstrator successfully detects and localizes targets, effectively suppresses high-power interference, and generates clear ISAR images of non-cooperative vessels. These findings validate the multifunction performance of the AESA demonstrator, confirming its suitability for advanced naval surveillance applications.

2605.28432 2026-05-28 eess.SP

Transformer-Based Heartbeat Monitoring with FMCW Radar Under Random Body Motion

基于Transformer的FMCW雷达心跳监测在随机身体运动下的研究

Matteo Pardi, Amir Hosein Oveis, Saba Kharabadze, Ajeet Kumar

AI总结 提出一种结合模型驱动信号处理与CNN-Transformer网络的混合框架,从77 GHz FMCW雷达数据中重构PPG信号,实现随机身体运动下的可靠心率与心率变异性估计。

Comments 6 pages, 5 figures. Accepted for publication in the Proceedings of the 2026 IEEE Radar Conference (RadarConf26)

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AI中文摘要

毫米波调频连续波(FMCW)雷达可实现非接触式心脏监测,但当呼吸和随机身体运动(RBM)扭曲雷达信号时,心跳估计变得具有挑战性。本文提出一种针对77 GHz FMCW雷达的混合框架,该框架结合了基于模型的信号处理与卷积神经网络(CNN)-Transformer网络。第一个模块从原始雷达数据中提取胸部位移并构建有意义的运动特征,第二个模块从提取的特征中重构类似光电容积描记(PPG)的信号。本研究中,同步PPG信号作为心跳监测的监督训练真值。该方法按照IEEE AESS雷达挑战问题I协议,使用官方数据集和性能指标在三种运动场景(静止、深呼吸和RBM)下进行评估。结果表明,所提出的架构在所有场景下都能可靠地重构PPG信号,在受控条件下实现高保真度,并在运动下保持稳健性能。即使在基准方法失效的情况下,也能实现可靠的平均心率(AHR)和心率变异性(HRV)估计,并在比较方法中获得最高总分。

英文摘要

Millimeter-wave Frequency Modulated Continuous Wave (FMCW) radar enables contactless cardiac monitoring, but heartbeat estimation becomes challenging when respiration and random body motion (RBM) distort the radar signal. In this paper, we propose a hybrid framework for 77 GHz FMCW radar that combines model-based signal processing with a Convolutional Neural Network (CNN)-Transformer network. The first block extracts chest displacement and constructs meaningful high-level motion features from raw radar data, while the second block reconstructs a photoplethysmography (PPG)-like signal from the extracted features. In this study, a synchronized PPG signal is used as the ground truth for heartbeat monitoring in supervised training. The method is evaluated following the IEEE AESS Radar Challenge Problem I protocol using the official datasets and figures of merit across three motion scenarios: stationary, deep breathing, and RBM. Results show that the proposed architecture reliably reconstructs the PPG signal in all scenarios, achieving high fidelity in controlled conditions and maintaining robust performance under motion. This enables reliable average heart rate (AHR) and heart rate variability (HRV) estimation even where benchmark methods fail, and leads to the highest total score among the compared approaches.

2605.28431 2026-05-28 eess.SP

A Unified Maximum-Likelihood Framework for 3D InISAR Phase Unwrapping with Outlier Rejection

一种用于3D InISAR相位解缠的统一最大似然框架及异常值剔除

Matteo Pardi, Francesco Mancuso, Elisa Giusti, Marco Martorella

AI总结 提出一种基于混合整数最小二乘理论的统一最大似然框架,用于3D InISAR相位解缠,无需空间连续性假设,并自然生成后验质量度量以剔除异常值。

Comments 6 pages, 4 figures. Accepted for publication in the Proceedings of the 2026 IEEE Radar Conference (RadarConf26)

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AI中文摘要

本文提出了一种用于三维干涉ISAR(3D InISAR)成像中相位解缠的新型数学框架。该方法基于逐散射体工作,不依赖任何空间连续性假设,因此适用于稀疏点云。该公式源自混合整数最小二乘(MILS)理论,这是一个在高斯噪声存在下联合估计整数和实数未知量的最优最大似然框架。它提供了一种统一的方式来处理通用传感器几何、多基线、多频率或混合设置。该方法还为每个解缠相位自然产生一个后验质量度量,可用于构建统计测试以剔除异常值。该算法易于实现,计算成本适合操作化系统。本文介绍了该框架的理论基础,并使用蒙特卡洛模拟在标准L形双频设置上进行了首次验证研究。结果表明,所提出的框架能够在具有挑战性的模糊条件下实现可靠的三维重建。

英文摘要

This paper presents a novel mathematical framework for phase unwrapping in three-dimensional interferometric ISAR (3D InISAR) imaging. The approach works on a scatterer-by-scatterer basis and does not rely on any spatial continuity assumptions, making it suitable for sparse point clouds. The formulation is derived from the Mixed-Integer Least Squares (MILS) theory, an optimal maximum-likelihood framework for joint estimation of integer and real unknowns in the presence of Gaussian noise. This provides a unified way to handle generic sensor geometries, multi-baseline, multi-frequency, or hybrid setups. The method also produces a natural a posteriori quality metric for each unwrapped phase, which can be used to build a statistical test to reject outliers. The algorithm is simple to implement and has a computational cost suitable for operational systems. This paper presents the theoretical foundations of the framework and a first validation study on a standard L-shaped dual-frequency setup using Monte Carlo simulations. Results show that the proposed framework enables reliable 3D reconstruction in challenging ambiguity conditions.

2605.28430 2026-05-28 math.PR

Limit theory for Lipschitz-localized statistics in random geometric models

随机几何模型中Lipschitz局部化统计量的极限理论

B. Błaszczyszyn, D. Yogeshwaran, J. E. Yukich

AI总结 针对一般标记欧几里得点过程,引入几何混合条件和Lipschitz局部化条件,证明了分数和的中心极限定理以及期望和方差渐近性,并应用于空间随机图上的自旋系统、相互作用扩散和粒子系统等。

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AI中文摘要

我们研究了一般标记(即带标签)欧几里得点过程中与局部依赖分数相关的和。我们在底层点过程上引入了几何混合条件,并在分数上引入了Lipschitz“局部化”条件,这些条件共同确保了分数和的中心极限定理以及期望和方差渐近性。我们的局部化条件是使用有界Lipschitz度量来表述的,提供了一个分布性准则。这与随机几何中的经典稳定化条件形成对比,后者通常基于停时集构造。为了展示我们一般框架的适用性,我们考虑了由空间随机图索引的几个随机过程。这些包括自旋系统、相互作用扩散和相互作用粒子系统。特别是,自旋系统突显了局部化条件的重要性。其他应用包括经验随机场和地统计布尔模型。

英文摘要

We study sums of locally dependent scores associated with general marked (i.e., labeled) Euclidean point processes. We introduce geometric mixing conditions on the underlying point process and a Lipschitz-"localization" condition on the scores, which jointly ensure a central limit theorem for the sums of the scores as well as expectation and variance asymptotics. Our localization condition is formulated using the bounded Lipschitz metric, providing a distributional criterion. This stands in contrast to the classical stabilization conditions in stochastic geometry, which are typically based on stopping-set constructions. To demonstrate the applicability of our general framework, we consider several stochastic processes indexed by spatial random graphs. These include spin systems, interacting diffusions, and interacting particle systems. In particular, spin systems highlight the importance of our localization condition. Additional applications include empirical random fields and geostatistical Boolean models.

2605.28426 2026-05-28 cs.DC cs.NA math.NA

Fault Tolerance of Accelerated Asynchronous Fixed-Point Iterations on Flexible Computing Infrastructure

灵活计算基础设施上加速异步不动点迭代的容错性

Evan Coleman, Masha Sosonkina

AI总结 研究异步迭代中收敛加速器(如Anderson加速)对掉队处理器引起的收敛退化的补偿效果,发现加速器在评估级扰动下有效,在迭代级损坏下失效。

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AI中文摘要

异步迭代方法允许工作节点使用过时数据,从而容忍掉队处理器,但代价是迭代变得不一致,可能降低收敛速度。我们研究Anderson加速等收敛加速器是否能补偿这种退化。我们实验研究了三种不动点迭代:稀疏线性系统的Jacobi方法、Bellman方程的值迭代和Hartree-Fock自洽场(SCF)迭代。实验使用高性能执行框架Ray进行,该框架抽象了分布式系统的复杂性,并允许以最小改动实现代码并行化和故障注入。我们建立了两个主要结果。首先,掉队容忍是普遍的:异步执行相对于同步执行(带100毫秒延迟的工作节点)提供了$2.9 imes$(Jacobi)、$7.7 imes$(VI)和$16.9 imes$(SCF)的墙上时钟加速,无论是否使用加速。其次,Anderson加速在异步下的有效性取决于陈旧性进入计算的方式。我们识别出两种陈旧性机制:迭代级损坏,其中陈旧工作节点的返回直接覆盖加速迭代的部分(如块Jacobi);以及评估级扰动,其中陈旧性作为不动点映射评估的有界扰动(如VI和SCF)。Anderson加速在第一种机制下完全失败,但在第二种机制下保留其优势,这与Toth等人(2017)的扰动分析一致。这种区别,而不是映射的压缩范数或光滑性,是加速是否能在异步执行中存活的主要决定因素。

英文摘要

Asynchronous iterative methods tolerate straggling processors by allowing workers to proceed with stale data, but at a cost: the iterates become inconsistent, potentially degrading convergence. We investigate whether convergence accelerators such as Anderson acceleration compensate for this degradation. We experimentally study three fixed-point iterations: the Jacobi method for sparse linear systems, value iteration for the Bellman equation, and the Hartree--Fock self-consistent field (SCF) iteration. The experiments are conducted using a high-performance execution framework Ray, which abstracts the complexity of distributed systems and enables code parallelization and fault injection with minimal changes. We establish two main results. First, straggler tolerance is universal: asynchronous execution provides wall-clock speedups of $2.9\times$ (Jacobi), $7.7\times$ (VI), and $16.9\times$ (SCF) over synchronous execution with a 100\,ms-delayed worker, independent of whether acceleration is used. Second, Anderson acceleration's effectiveness under asynchrony depends on where staleness enters the computation. We identify two staleness mechanisms: iterate-level corruption, where stale worker returns directly overwrite portions of the accelerated iterate (as in block Jacobi), and evaluation-level perturbation, where staleness acts as a bounded perturbation to the fixed-point map evaluation (as in VI and SCF). Anderson acceleration fails categorically under the first mechanism but retains its benefits under the second, consistent with the perturbation analysis of Toth et al.\ (2017). This distinction, rather than the contraction norm or smoothness of the map, is the primary determinant of whether acceleration survives asynchronous execution.

2605.28425 2026-05-28 cond-mat.mes-hall cond-mat.mtrl-sci

Symmetry-Selective Topological Magnon Engineering by Phonon Angular Momentum

对称性选择性的拓扑磁振子工程:通过声子角动量

Markus Weißenhofer, Philipp Rieger, Chandan K. Singh, M. S. Mrudul, Sergiy Mankovsky, Peter M. Oppeneer

AI总结 基于第一性原理自旋-晶格耦合和Floquet理论,通过相干驱动声子实现磁振子能带结构的对称选择性调控,利用携带声子角动量的圆偏振和椭圆偏振声子打开并调节狄拉克点能隙,产生和反转拓扑磁振子相。

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AI中文摘要

贝里曲率的动态控制仍然是拓扑相工程中的一个突出挑战。在这里,我们基于 extit{ab initio}自旋-晶格耦合和Floquet理论,展示了通过相干驱动声子对磁振子能带结构的控制。我们表明这种控制是对称选择性的:线偏振声子保持能谱不变,而携带有限声子角动量(PAM)的圆偏振和椭圆偏振声子诱导手性相互作用,打开并调节狄拉克点处的能隙,产生和反转拓扑磁振子相。能隙大小和陈数直接由PAM决定,实现了手性选择性拓扑控制。应用于单层CrI$_3$,并通过对称性分析支持,我们的结果确立了驱动晶格动力学作为工程拓扑玻色子激发的一般途径,以及用于磁性的Floquet控制的通用平台。

英文摘要

Dynamical control of Berry curvature remains an outstanding challenge in the engineering of topological phases. Here, we demonstrate control of magnon band structures via coherently driven phonons, based on \textit{ab initio} spin-lattice coupling and Floquet theory. We show that this control is symmetry selective: linearly polarized phonons leave the spectrum unchanged, whereas circular and elliptical phonons carrying finite phonon angular momentum (PAM) induce chiral interactions that open and tune gaps at Dirac points, generating and reversing topological magnon phases. The gap magnitude and Chern numbers are directly governed by the PAM, enabling handedness-selective topology control. Applied to monolayer CrI$_3$, and supported by symmetry analysis, our results establish driven lattice dynamics as a general route to engineering topological bosonic excitations and a versatile platform for Floquet control of magnetism.

2605.28423 2026-05-28 math.CO

Intersection Orbital Graphs of Permutation Groups and Reconstruction of Simple Groups

置换群的交轨道图与单群的重构

Shahram Mehry

AI总结 引入与两个置换群相关的交轨道图,并证明该图可唯一确定非交换单群的结构。

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AI中文摘要

我们引入了与有限集合Ω上两个置换群G1, G2 ≤ Sym(Ω)相关的交轨道图Γ(G1, G2; Ω)。

英文摘要

We introduce the \emph{intersection orbital graph} $Γ(G_1, G_2; Ω)$ associated with two permutation groups $G_1, G_2 \leq \mathrm{Sym}(Ω)$ on a finite set $Ω$.

2605.28419 2026-05-28 math.LO math.GR math.RA

Ordinal semigroups

序数半群

Paolo Lipparini

AI总结 本文针对部分无穷运算引入结合性概念,证明若对某个无穷序数γ,所有≤γ序数索引的序列上定义了结合无穷运算,则该运算可唯一扩展至任意基数|γ|的序数索引的序列。

Comments 11 pages

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AI中文摘要

在之前的一篇论文中,我们引入了部分无穷运算的结合性概念。这里我们证明,如果γ是一个无穷序数,并且某个结合无穷运算对所有由≤γ的序数索引的序列有定义,那么该运算可以唯一地扩展为适用于每个由基数为|γ|的任意序数索引的序列。特别地,如果某个结合运算对所有有限序列以及所有ω索引的序列有定义,那么该运算可以唯一地扩展为适用于每个由可数序数索引的序列。

英文摘要

In a previous paper we introduced a version of associativity for a partial infinitary operation. We prove here that if $γ$ is an infinite ordinal and some associative infinitary operation is defined for all sequences indexed by ordinals $ \leq γ$, then such an operation can be uniquely expanded to apply to every sequence indexed by any ordinal of cardinality $ |γ|$. In particular, if some associative operation is defined for all finite sequences as well as for all $ ω$-indexed sequences, then the operation can be uniquely expanded to apply to every sequence indexed by a countable ordinal.

2605.28417 2026-05-28 math.DS

The fused asset flow model: stability, bifurcation, and contagion in multi-asset markets with heterogeneous investors

融合资产流模型:异质投资者多资产市场中的稳定性、分岔与传染

Mario Cavani

AI总结 本文提出一个统一的多资产多群体资产流模型,整合行为金融学三大基础框架,通过常微分方程组刻画价格、现金、股票和情绪动态,发现基本均衡通过超临界Hopf分岔失稳产生极限环,并验证了均衡流形、分岔阈值和不对称传染模式。

Comments 53 pages

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AI中文摘要

本文提出了一个统一的多资产、多群体资产流模型,整合了行为金融学文献中的三个基础框架。该模型捕捉了多个投资者群体交易多种资产的金融市场动态,每个群体具有不同的趋势跟踪(动量)和基于价值(基本面)策略。与经典的有效市场模型不同,我们的框架明确考虑了现金和股票的有限性、购买决策中的非对称跨资产耦合以及群体间的内生财富再分配。我们推导了控制价格、现金、股票和情绪动态的完整常微分方程组,并建立了所有物理相关变量的正性和有界性的基本性质。均衡集被表征为由现金分布参数化的流形,其中基本均衡是一个特殊点。通过线性稳定性分析,我们确定了基本均衡通过超临界Hopf分岔失去稳定性的条件,从而产生持续的极限环。该模型针对三篇基准论文进行了验证:DeSantis、Swigon和Caginalp(2012)的单资产多群体模型;Bulut、Merdan和Swigon(2019)的两资产单群体模型;以及Cavani(2026)的两资产两群体尼日利亚-利比亚石油市场模型。我们的数值模拟再现了所有关键理论预测,包括均衡流形、Hopf分岔阈值、极限环周期和不对称传染模式。

英文摘要

This paper presents a unified multi-asset, multi-group asset-flow model that integrates three foundational frameworks from the behavioral finance literature. The model captures the dynamics of financial markets where multiple assets are traded by multiple investor groups, each with distinct trend-following (momentum) and value-based (fundamental) strategies. Unlike classical efficient market models, our framework explicitly incorporates the finiteness of cash and shares, asymmetric cross-asset coupling in buying decisions, and endogenous wealth redistribution across groups. We derive the complete system of ordinary differential equations governing price, cash, share, and sentiment dynamics, and establish the fundamental properties of positivity and boundedness for all physically relevant variables. The equilibrium set is characterized as a manifold parameterized by cash distribution, with the fundamental equilibrium as a special point. Through linear stability analysis, we identify conditions under which the fundamental equilibrium loses stability via a supercritical Hopf bifurcation, giving rise to persistent limit cycles. The model is validated against three benchmark papers: the single-asset multi-group model of DeSantis, Swigon, and Caginalp (2012); the two-asset single-group model of Bulut, Merdan, and Swigon (2019); and the two-asset two-group Nigeria-Libya oil market model of Cavani (2026). Our numerical simulations reproduce all key theoretical predictions, including equilibrium manifolds, Hopf bifurcation thresholds, limit cycle periods, and asymmetric contagion patterns.

2605.28416 2026-05-28 math.GR math.RA

One-sided inverses in noncommutative infinitary semigroups

非交换无穷半群中的单侧逆

Paolo Lipparini

AI总结 本文研究非交换无穷半群中单侧逆的存在性,通过构造例子表明在非交换情形下可以存在不同于单位元的元素其乘积为单位元,这与交换情形形成对比。

Comments 18 pages

详情
AI中文摘要

在之前的一篇论文中,我们引入了部分无穷非交换半群,并特别指出与文献中先前研究的交换情形相比,会出现显著差异。例如,在交换情形下,仅假设可数乘积 $abababa\dots$ 有定义,我们不可能存在一个无穷单位元 $e$ 以及两个元素 $a \neq e$, $b \neq e$ 使得 $ab = e$。这里我们证明在非交换情形下这是可能的,实际上,我们可以在一个可数集上构造一个具有完全单位元的无穷半群,使得运算对每个索引的线性有序集都有定义。

英文摘要

In a former paper we introduced partial infinitary noncommutative semigroups and showed, among other, that significant differences arise in comparison with the commutative case, previously studied in the literature. For example, in the commutative case we cannot have an infinitary identity $e$ together with two elements $a \not= e$, $b \not= e$ such that $ab= e$, just under the assumption that the countable product $abababa\dots$ is defined. Here we show that this is possible in the noncommutative case, actually, we can have an infinitary semigroup on a countable set with a complete identity and such that the operation is defined for every indexed linearly ordered set.