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2606.08853 2026-06-09 econ.EM stat.ME 新提交

AI-Assisted Variance Reduction in Randomized Experiments

AI辅助的随机实验方差缩减

David Arbour, Eli Ben-Michael, Avi Feller, Apoorva Lal, Lo-Hua Yuan

AI总结 提出将AI预测作为协变量纳入标准回归调整,以降低随机实验方差,具有“无害”特性,并通过模拟和三个实证应用验证了效率提升。

Comments camera ready for KDD 2026

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AI中文摘要

生成式AI和大语言模型可以从丰富、非结构化的输入中生成人类行为的逼真预测,几乎不需要特定任务的训练数据。最近的工作使用这些“数字孪生”预测来补充调查和实验中的人类响应。我们研究了使用AI生成的预测来减少随机实验方差的特殊情况。我们认为这样做不需要新的估计量,研究人员可以简单地将AI预测作为协变量纳入标准回归调整,类似于调整预后评分。这种方法的一个好处是“无害”特性,即当预测无信息时,调整后的估计量会退回到未调整的均值差。其他方法,如预测驱动推断的变体,没有这种保证。我们提供了实施指南,包括如何从离散的LLM输出中获得连续分数,以及如何使用LLM将非结构化输入特征化为辅助协变量。我们在模拟和三个实证应用中展示了这些想法:一个调查元研究、一个电子邮件营销A/B测试和一个大规模技术平台实验。总体而言,效率提升虽然适度但真实,在包含大量文本和其他非结构化数据的研究中收益更大。我们还从经验上确认了无害特性。鉴于这些收益和有限的成本,我们建议将调整AI生成的预测作为常规实证实践。

英文摘要

Generative AI and large language models can produce realistic predictions of human behavior from rich, unstructured inputs with little to no task-specific training data. Recent work uses these ``digital twin'' predictions to supplement human responses in surveys and experiments. We study the special case of using AI-generated predictions to reduce variance in randomized experiments. We argue that doing so requires no new estimators and that researchers can simply include AI predictions as covariates in standard regression adjustment, analogous to adjusting for a prognostic score. A benefit of this approach is a ``do no harm'' property whereby the adjusted estimator reverts to the unadjusted difference in means when predictions are uninformative. Other methods, such as variants of prediction-powered inference, do not have this guarantee. We provide implementation guidance, including how to obtain continuous scores from discrete LLM outputs and how to use LLMs to featurize unstructured inputs as auxiliary covariates. We demonstrate these ideas in simulations and three empirical applications: a survey mega-study, an email marketing A/B test, and a large-scale technology platform experiment. Overall, efficiency gains are real if modest, with greater benefits in studies that contain substantial text and other unstructured data. We also confirm the do no harm property empirically. Given these gains and limited costs, we recommend adjusting for AI-generated predictions as a regular empirical practice.

2606.08852 2026-06-09 cs.LO cs.DC 新提交

Parallel SMT Solving via Dynamic Partitioning, Core-Guided Pruning, and Online Backbone Detection

通过动态划分、核心引导剪枝和在线骨干检测的并行SMT求解

Ilana Shapiro, Sorin Lerner, Nikolaj Bjørner

AI总结 提出一种动态构建搜索空间二叉划分树的并行框架,利用基于核心的CDCL剪枝和在线骨干检测,在Z3中实现并超越现有并行求解器。

Comments Submitted to FMCAD 2026

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AI中文摘要

在现代CPU架构中利用并行性仍然是优化SMT求解器的一个长期挑战。我们引入了一种新颖的并行框架,该框架通过在求解过程中从工作线程的VSIDS统计信息中采样,动态构建搜索空间的二叉划分树。我们利用基于核心的CDCL风格剪枝的全部能力来持续缩小划分树。我们通过将在线骨干检测集成到工作线程中,以及一种按需终止机制来积极消除已剪枝子问题的工作,进一步优化了我们的架构。所得到的算法具有高度的通用性,并能随可用资源有效扩展。我们在Z3 SMT求解器中实现了我们的方法,并证明它在来自SMT-COMP 2025并行赛道六个逻辑的具有挑战性的基准测试中,优于顺序Z3和现有的最先进并行框架。

英文摘要

Exploiting parallelism in modern CPU architectures remains a longstanding challenge in optimizing SMT solvers. We introduce a novel parallel framework that dynamically builds a binary partition tree of the search space by sampling from workers' VSIDS statistics during solving. We leverage the full power of core-based CDCL-style pruning to continuously shrink the partition tree. We further optimize our architecture by incorporating online backbone detection into worker threads, as well as a terminate-on-demand mechanism to eagerly eliminate work on pruned subproblems. The resulting algorithm is highly generalizable and scales effectively with available resources. We implement our approach in the Z3 SMT solver and demonstrate that it outperforms both sequential Z3 and existing state-of-the-art parallel frameworks on challenging benchmarks from six logics in the SMT-COMP 2025 Parallel Track.

2606.08851 2026-06-09 cs.SI cs.CY 新提交

Enforcing Trust Accountability with Backward Propagation

通过反向传播实现信任问责

Wenbo Wu, George Konstantinidis

AI总结 提出RepuLink双层声誉模型,通过反向背书惩罚与奖励传播机制,实现信任传播的问责性并缓解冷启动问题,在真实数据集上优于基线方法。

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AI中文摘要

信任与声誉管理是分布式网络中可靠交互的基础,但现有信任模型仅依赖基于交互的信任信号的前向传播。当负面交互发生时,它们缺乏强有力的机制来对传播的信任信号进行问责。此外,这类模型通常无法为交互历史稀疏的新加入节点初始化,导致冷启动问题。在本文中,我们提出RepuLink,一种双层声誉模型,将背书网络与交互反馈网络耦合。RepuLink集成了两种并行的反向传播机制:反向背书惩罚传播(BEPP),递归惩罚行为不当节点的背书者;以及反向背书奖励传播(BERP),奖励表现良好节点的背书者。两者共同作用,RepuLink强制执行背书问责并激励积极行为,形成正向交互反馈循环。背书层进一步为新加入节点提供可解释的、基于背书者权重的信任初始化。在真实数据集上针对代表性信任传播基线的实验表明,RepuLink在仅交互和完整双层设置下,在四个评估指标上均表现更优,同时保持相当的效率。

英文摘要

Trust and reputation management underpins reliable interactions in distributed networks, yet existing trust models rely solely on forward propagation of interaction-based trust signals. They lack robust mechanisms to enforce accountability for the propagated trust signals when negative interactions occur. In addition, such models often fail to initialize newly joined nodes with sparse interaction history, leading to the cold-start problem. In this paper, we propose RepuLink, a two-layer reputation model that couples an endorsement network with an interaction feedback network. RepuLink integrates two concurrent backward propagation mechanisms: Backward Endorsement Penalty Propagation (BEPP), which recursively penalizes endorsers of misbehaving nodes, and Backward Endorsement Reward Propagation (BERP), which rewards endorsers of well-performing nodes. Together, RepuLink enforces endorsement accountability and incentivizes positive behaviors, which form a positive interaction feedback loop. The endorsement layer further provides explainable, endorser-weighted trust initialization for newly joined nodes. Experiments on real-world datasets against representative trust propagation baselines demonstrate that RepuLink outperforms across four evaluation metrics in both interaction-only and full two-layer settings, while preserving comparable efficiency.

2606.08848 2026-06-09 math.NT 新提交

Zeta functions over curves

曲线上的Zeta函数

F. Pellarin, with an appendix by G. H. Ferraro

AI总结 本文综述了David Goss发展的zeta函数理论,并与另一种基于有限域上曲线的zeta函数构造方法进行比较,介绍了Ferraro的有理性定理及其在相对zeta函数整函数性质中的应用。

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AI中文摘要

本文综述了David Goss从1979年开始发展的理论,该理论围绕Carlitz zeta值以及正特征局部域中其他显著形式级数构造zeta函数。在描述Goss理论时,我们将看到它主要受经典复值zeta和$L$-函数理论的类比启发。我们将Goss理论与另一种近期出现的构造zeta和$L$-函数的方法进行比较。第二种类型的函数定义域为有限域上的曲线,标量扩展到正特征的完备代数闭域。第二种函数与Goss函数相互作用但本质不同。我们将回顾Ferraro的一个有理性定理,该定理允许引入某种类似于Riemann $\xi$函数的模拟。在描述Ferraro证明的过程中,我们介绍了一些进入该理论的基本工具:shtuka除子和函数、特殊函数、Anderson motive、Drinfeld模等。我们讨论了某些相对zeta函数,它们可被视为Dedekind zeta函数的对应物。特别地,我们使用Goss引入的方法证明这些函数延拓为整函数。本文包含Ferraro的一个附录,其中(在特殊情况下)从Anglès、Ngo Dac和Tavares Ribeiro的一个公式与Ferraro的有理性公式的结合推导出上述相对zeta函数的整函数性质。Ferraro还提出了关于该函数在规范点$\Xi$处消失阶的一个猜想及一些数值证据。

英文摘要

In this paper we review the theory that David Goss developed, starting from 1979, to construct zeta functions around Carlitz zeta values and other remarkable formal series in local fields of positive characteristic. In the description of Goss' theory, we will see how it is primarily motivated by analogies with the classical theory of complex valued zeta and $L$-functions. We compare Goss' theory with another way of constructing zeta and $L$-functions that emerged in more recent times. The functions in the second type have as domains curves over finite fields, with the scalars extended to complete and algebraically closed fields of positive characteristic. The second type of functions interacts with Goss' functions but remains fundamentally different. We shall review a rationality theorem of Ferraro that allows, among others, to introduce some kind of analogue of the function $ξ$ of Riemann. In the path of describing Ferraro's proof, we present some essential tools useful to get into the theory: shtuka divisors and functions, special functions, Anderson motives, Drinfeld modules, among others. We discuss certain relative zeta functions that can be considered as counterparts of Dedekind zeta functions. In particular, we use methods introduced by Goss to prove that these functions extend to entire functions. The paper contains an appendix by Ferraro where the property of entireness of the above relative zeta functions is deduced (in a special case) from the conjunction of a formula by Anglès, Ngo Dac and Tavares Ribeiro and Ferraro's rationality formula. Ferraro also presents a conjecture on the order of vanishing of this function at the canonical point $Ξ$ and some numerical evidences.

2606.08846 2026-06-09 physics.chem-ph 新提交

Collisional energy transfer in ethanimine + He system

乙亚胺 + He 体系中的碰撞能量转移

Vivek Vijay, Francesca Tonolo, Ernesto Quintas-Sánchez, Adrian Batista Planas, Carolin Joy, Richard Dawes, François Lique, Dmitri Babikov

AI总结 为解释乙亚胺E/Z异构体在星际介质中的非平衡转动分布,构建了与He相互作用的精确势能面,并采用全量子耦合通道、耦合态及混合量子/经典方法计算态-态碰撞截面,发现Δj=0且Δk_a=0或Δk_c=0的强倾向性,两异构体能量转移差异约10%。

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AI中文摘要

乙亚胺分子CH3CHNH是天文学家在银河系中心化学富集分子云中探测到的益生分子之一。观测表明,乙亚胺的E-和Z-异构体转动能级布居呈非平衡分布,这是辐射过程与背景气体(如He和H2)碰撞竞争的结果。准确解释这些观测需要包含碰撞态-态跃迁过程的辐射传输模型。为此,为计算两种乙亚胺异构体的态-态跃迁截面,构建了它们与He原子相互作用的精确势能面,并采用了三种非弹性散射的互补方法:全量子耦合通道和耦合态方法,以及混合量子/经典理论。报道了向Δj=0且Δk_a=0(伴随Δk_c=±1)或Δk_c=0(伴随Δk_a=±1)跃迁的强倾向性,并确定了该效应的起源。发现两种异构体之间的能量转移存在约10%的小但不可忽略的差异。讨论了混合量子/经典方法在更高碰撞能量下用于碰撞能量转移的实用性。

英文摘要

The ethanimine molecule, CH3CHNH, is one of the prebiotic molecules detected by astronomers in chemically-rich molecular clouds in the Galactic Center. The observations indicate a non-equilibrium distribution of rotational state populations in both the E- and Z-isomers of ethanimine, resulting from the competition between radiative processes and collisions with background gases such as He and H2. Accurate interpretation of these observations requires the use of radiative transfer models with collisional state-to-state transition processes included. Here, in order to compute cross sections for state-to-state transitions in both ethanimine isomers, accurate potential energy surfaces for their interaction with a He atom were constructed and three complementary methods for inelastic scattering were utilized: full-quantum coupled-channel and coupled-states methods, and the mixed quantum/classical theory. Strong propensities of transitions toward $Δj = 0$ and either $Δk_a = 0$ (with $Δk_c = \pm 1$) or $Δk_c = 0$ (with $Δk_a = \pm 1$) are reported and the origin of this effect is identified. Small but non-negligible differences between energy transfer in the two isomers, on the order of 10%, were found. The utility of the mixed quantum/classical approach to collisional energy transfer at higher collision energies is discussed.

2606.08845 2026-06-09 quant-ph 新提交

Energy-Efficient Satellite Wake-Up via Bosonic Identification: The Role of Synchronization

通过玻色子识别实现节能卫星唤醒:同步的作用

Gökhan Elmas, Janis Nötzel

AI总结 研究在同步约束下卫星广播识别信号以唤醒地面站的场景,发现识别性能随块长增加而提升,但同步精度下降,且同步所需能量远高于识别信号。

Comments Accepted for presentation at European Wireless 2026

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AI中文摘要

信息论中的识别概念描述了一种发送-接收架构,其中接收器仅检查特定消息是否被发送,从而有望实现低能耗接收器设计。在低接收能量条件下,量子接收器是研究系统极限的有前途的工具。然而,已知的信息论最优识别码通常假设完美同步。在本工作中,我们研究了在明确同步约束下的卫星场景中的确定性识别,其中卫星广播特定用户设备(UE)的签名,该UE假设连接到多个可能的地面站(GS)之一,目标是与目标UE建立通信。在所提出的设计中,假设一种特定的相位编码相干态时钟方案,其中离散时间索引由单位圆上的等距相位旋转表示,我们的结果揭示了一个基本的不对称性:在任何传输功率下,识别性能随块长增加而改善,而同步精度下降。特别地,将卫星时钟传输到GS所需的能量可能比识别信号所需的能量高出几个数量级。这表明同步强烈影响识别性能,并激励研究玻色子码在抖动下的纠错能力。

英文摘要

The information-theoretic concept of identification describes a sender-receiver architecture in which the receiver only checks whether a particular message was sent or not, thereby promising a low-energy receiver design. In low received-energy regimes, quantum receivers are a promising tool for studying the system limits. However, the known information-theoretically optimal identification codes typically assume perfect synchronization. In this work, we study deterministic identification in a satellite setting under explicit synchronization constraints, where a satellite broadcasts the signature of a specific User Equipment (UE) which it assumes to be attached to one out of several possible Ground Station (GS), with the goal of establishing communication with the target UE. Within the proposed design, and assuming a specific phase-encoded coherent-state clock scheme in which the discrete time index is represented by equidistant phase rotations on the unit circle, our results reveal a fundamental asymmetry: At any transmission power, identification performance improves with blocklength, whereas synchronization accuracy degrades. In particular, the energy needed for transmitting the satellite clock to the GS can be several orders of magnitude higher than the one needed for the identification signal. This indicates that synchronization strongly impacts identification performance and motivates the investigation of the error-correcting capabilities of bosonic codes under jitter.

2606.08842 2026-06-09 math.NT math.DS 新提交

Transcendence of simple geodesics on finite modular covers

有限模覆盖上简单测地线的超越性

Christopher-Lloyd Simon

AI总结 研究有限指数子群对应的模覆盖上简单测地线的端点性质,证明若测地线简单则端点要么有理数、二次无理数或超越数,并验证了最小测地线叶层情形。

Comments 29 pages, 7 figures

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AI中文摘要

实射影直线 $\mathbb{R}\mathbf{P}^1$ 是 $\mathbf{HP}=\{z\in \mathbb{C}\colon \Im(z)>0\}$ 的边界,后者是双曲平面的一个模型,其测地线空间等同于 $\mathcal{G}(\mathbf{HP})=\mathbb{R}\mathbf{P}^1 \times \mathbb{R}\mathbf{P}^1 \setminus \mathrm{diagonal}$。模群 $Γ=\operatorname{PSL}_2(\mathbb{Z})$ 作用在 $\mathbf{HP}$ 上,商为模轨道体 $\mathbf{M}=Γ\backslash \mathbf{HP}$。考虑模群的有限指数子群 $Γ^\prime \subset Γ= \operatorname{PSL}_2(\mathbb{Z})$,对应于有限覆盖 $\mathbf{M} \to \mathbf{M}^\prime$。一条测地线 $(ξ^-,ξ^+)\in \mathcal{G}(\mathbf{HP})$ 模 $Γ^\prime$ 投影为 $\mathbf{M}^\prime$ 中的测地线 $ξ^\prime$。我们猜想:若 $ξ^\prime$ 是简单的,则 $ξ^+$ 要么是有理数、二次无理数,要么是超越数。我们证明了该猜想对最小测地线叶层的叶子成立。我们还解释了为何该猜想对与导出子群 $Γ^\prime = [Γ, Γ]$ 相关的模环面覆盖中的所有简单测地线已知成立。

英文摘要

The real projective line $\mathbb{R}\mathbf{P}^1$ is the boundary of $\mathbf{HP}=\{z\in \mathbb{C}\colon \Im(z)>0\}$, a model of the hyperbolic plane whose space of geodesics identifies with $\mathcal{G}(\mathbf{HP})=\mathbb{R}\mathbf{P}^1 \times \mathbb{R}\mathbf{P}^1 \setminus \mathrm{diagonal}$. The modular group $Γ=\operatorname{PSL}_2(\mathbb{Z})$ acts on $\mathbf{HP}$ with quotient the modular orbifold $\mathbf{M}=Γ\backslash \mathbf{HP}$. Consider a finite-index subgroup of the modular group $Γ^\prime \subset Γ= \operatorname{PSL}_2(\mathbb{Z})$ corresponding to a finite cover $\mathbf{M} \to \mathbf{M}^\prime$. A geodesic $(ξ^-,ξ^+)\in \mathcal{G}(\mathbf{HP})$ projects $\bmod{Γ^\prime}$ to a geodesic $ξ^\prime \subset \mathbf{M}^\prime$. We conjecture that if $ξ^\prime$ is simple, then $ξ^+$ is either rational or quadratic or transcendental. We prove this conjecture for leaves of minimal geodesic laminations. We explain why the conjecture is known for all simple geodesics in the modular torus cover associated to the derived subgroup $Γ^\prime = [Γ, Γ]$.

2606.08839 2026-06-09 cond-mat.stat-mech nucl-th quant-ph 新提交

Time Evolution of Heat Conduction in a Generalized Model of Brownian Motion

广义布朗运动模型中热传导的时间演化

T. Koide, F. Nicacio

AI总结 通过广义布朗运动模型研究谐振子网络的热传导,推导稳态热流解析表达式,证实傅里叶定律和微观热边界电阻,并数值分析热流的时间演化,发现瞬时热流方向由相互作用类型决定。

Comments 17 pages, 16 figures

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AI中文摘要

我们研究了一个由广义布朗运动模型描述的、与热浴相互作用的谐振子网络的热传导性质。该模型在动量和位置方程中均包含噪声和耗散项。这种推广源于与Gorini-Kossakowski-Sudarshan-Lindblad (GKSL)方程一致性的要求。由于基于速度的热流标准定义在此框架下数学上不一致,我们基于随机能量学的扩展框架推导了稳态热流的解析表达式。我们确认傅里叶定律(线性热响应)成立,并且该模型自然地捕捉到微观热边界电阻,类似于卡皮查电阻。这表明我们的广义模型可作为模拟非平衡过程的有效现象学框架,标志着向随机和量子热力学统一表述迈出的关键一步。此外,我们通过数值求解相关函数的微分方程,分析了热传导的时间演化。与标准布朗运动不同,广义模型产生连续但处处不可微的动量和位置轨迹(过阻尼动力学的特征)。最后,我们展示了当粒子间相互作用开启时,热流表现出特征性的瞬态行为。具体而言,出现瞬时热流,其方向严格由相互作用是吸引还是排斥决定,这与标准模型的预测显著不同。

英文摘要

We investigate the properties of heat conduction in a network of harmonic oscillators interacting with heat baths, described by a generalized model of Brownian motion. This model includes noise and dissipation terms in both the momentum and position equations. This generalization is motivated by the requirement of consistency with the Gorini-Kossakowski-Sudarshan-Lindblad (GKSL) equation. Because standard definitions of heat current based on velocity become mathematically inconsistent in this framework, we derive an analytical expression for the steady-state heat flow based on an extended framework of stochastic energetics. We confirm that Fourier's law (linear thermal response) is satisfied and that the model naturally captures microscopic thermal boundary resistance, analogous to Kapitza resistance. This demonstrates that our generalized model functions as a valid phenomenological framework for simulating non-equilibrium processes, marking a crucial step toward a unified formulation of stochastic and quantum thermodynamics. Furthermore, we analyze the time evolution of heat conduction by numerically solving the corresponding differential equations for the correlation functions. Unlike standard Brownian motion, the generalized model generates continuous and nowhere differentiable trajectories for both momentum and position (as is characteristic of overdamped dynamics). Finally, we show that the heat current exhibits characteristic transient behavior when the inter-particle interaction is switched on. Specifically, an instantaneous heat flow emerges, whose direction is strictly governed by whether the interaction is attractive or repulsive, significantly differing from the predictions of the standard model.

2606.08838 2026-06-09 gr-qc astro-ph.HE 新提交

Line-of-sight acceleration in compact binaries with higher harmonics and eccentricity

含高阶谐波和偏心率的致密双星中的视线加速度

Soumen Roy, Justin Janquart

AI总结 重新推导了致密双星中的视线加速度效应,并在含进动和高阶模式的准圆形波形模型及偏心波形模型中一致实现,用于探测环境对双星形成的影响。

Comments 16 pages, 8 figures

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AI中文摘要

引力波的直接探测为探究致密双星并合的物理起源提供了独特机会。这些系统的形成通道仍存在广泛争议,其中一部分可能起源于动力学环境或活动星系核。在这样的环境中形成的双星预计会受到来自周围环境的视线加速度,这可以在观测到的引力波信号上留下特征印记。在这里,我们重新推导了视线加速度效应,并将其实现于含进动和高阶模式的最先进的准圆形波形模型中。我们还在偏心波形模型中实现了这些修正,并将其一致地应用于所有贡献谐波。利用该模型,我们研究了这些效应对视线加速度推断的影响,并分析了LIGO和Virgo第三次观测运行期间观测到的几个有趣的GWTC事件。我们未在这些事件中发现视线加速度的实质性证据。我们还表明,高阶谐波之间视线加速度的不一致处理可能导致有偏的结论。我们的模型为在当前和未来的引力波观测中揭示视线加速度提供了一个稳健的框架,从而能够更精确地探测致密双星形成中的环境特征。

英文摘要

Direct detections of gravitational waves provide a unique opportunity to probe the astrophysical origin of compact binary mergers. The formation channels of these systems remain highly debated, and a fraction may originate in dynamical environments or active galactic nuclei. Binaries formed in such environments are expected to experience line-of-sight acceleration from their surroundings, which can imprint characteristic signatures on the observed gravitational-wave signal. Here, we re-derive the line-of-sight acceleration effects and implement them in state-of-the-art quasi-circular waveform models with precession and higher-order modes. We also implement the corrections in eccentric waveform models, applying them consistently to all contributing harmonics. Using this model, we investigate the impact of these effects on the inference of line-of-sight acceleration and analyze a few interesting GWTC events observed during the third observing run of LIGO and Virgo. We find no substantial evidence for line-of-sight acceleration in these events. We also show that an inconsistent treatment of line-of-sight acceleration between higher harmonics can lead to biased conclusions. Our model provides a robust framework for uncovering line-of-sight acceleration in current and future gravitational-wave observations, enabling more accurate probes of environmental signatures in compact-binary formation.

2606.08837 2026-06-09 math.DG math.AP 新提交

Asymptotic Profiles and Non-Trivial Breathers in Kahler-Ricci Flow

Kahler-Ricci流中的渐近轮廓与非平凡呼吸子

Longteng Chen

AI总结 研究渐近锥形梯度Kahler-Ricci扩张子上Kahler-Ricci流解的长时间行为与初始数据在空间无穷远处渐近行为的关系。

Comments 28 pages, 1 figure, all comments are welcome!

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AI中文摘要

本文研究了渐近锥形梯度Kahler-Ricci扩张子上Kahler-Ricci流解的长时间行为与其初始数据在空间无穷远处渐近行为之间的关系。

英文摘要

In this paper, we investigate the relationship between the long time behaviour of solutions to the Kahler-Ricci flow on an asymptotically conical gradient Kahler-Ricci expander and the asymptotic behaviour of their initial data at spatial infinity.

2606.08836 2026-06-09 eess.SY cs.SY 新提交

Adaptive Model Predictive Control of Nonlinear Generic Urban Air Mobility Using Linear Parameter-Varying Systems

基于线性参数变系统的非线性通用城市空中交通自适应模型预测控制

Tri Ngo

AI总结 提出一种针对全飞行包线内非线性城市空中交通飞行器的自适应模型预测控制框架,利用线性参数变表示在线更新预测模型,并采用NSGA-II多目标优化进行控制器调谐,在NASA GUAM模型上验证了改进的轨迹跟踪和鲁棒性。

Comments This paper was accepted for presentation at the Vertical Flight Society's 82nd Annual Forum & Technology Display, West Palm Beach, FL, USA, May 5-7, 2026

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AI中文摘要

本文提出了一种适用于全飞行包线内非线性城市空中交通(UAM)飞行器的自适应模型预测控制(MPC)框架。该方法利用线性参数变(LPV)表示在线更新预测模型,从而能够准确捕捉与分布式电推进(DEP)eVTOL飞行器相关的强非线性和时变动力学。为了系统性地解决MPC调谐的高维和耦合特性,采用基于NSGA-II的多目标进化优化策略,并引入状态和控制输入的正规化以确保平衡加权和有意义的探索设计空间。所得控制器明确考虑了执行器约束,并支持可重构控制分配以实现容错运行。该框架在NASA通用城市空中交通(GUAM)模型的非线性仿真中进行了评估,并与鲁棒伺服机构线性二次调节器(RSLQR)进行了基准比较。结果表明,所提出的自适应MPC在标称条件和执行器退化场景(包括部分电机故障)下均能实现改进的轨迹跟踪和增强的鲁棒性,同时在整个飞行阶段保持约束满足。

英文摘要

This paper presents an adaptive model predictive control (MPC) framework for nonlinear urban air mobility (UAM) vehicles operating across the full flight envelope. The proposed approach leverages a linear parameter-varying (LPV) representation to update the predictive model online, enabling accurate capture of strongly nonlinear and time-varying dynamics associated with distributed electric propulsion (DEP) eVTOL aircraft. To systematically address the high-dimensional and coupled nature of MPC tuning, a multi-objective evolutionary optimization strategy based on NSGA-II is employed, incorporating proper normalization of states and control inputs to ensure balanced weighting and meaningful exploration of the design space. The resulting controller explicitly accounts for actuator constraints and enables reconfigurable control allocation for fault-tolerant operation. The framework is evaluated in nonlinear simulations using NASA's Generic Urban Air Mobility (GUAM) model and benchmarked against a robust servomechanism linear quadratic regulator (RSLQR). Results demonstrate that the proposed adaptive MPC achieves improved trajectory tracking and enhanced robustness under both nominal conditions and actuator degradation scenarios, including partial motor failure, while maintaining constraint satisfaction throughout all flight regimes.

2606.08834 2026-06-09 math.CO math-ph math.MP 新提交

Area and water-capacity statistics for upper hulls of Dyck paths

Dyck路径上壳的面积与蓄水容量统计

Aleksander L. Owczarek, Thomas Prellberg

AI总结 研究Dyck路径在面积和蓄水容量双重约束下的计数,通过上壳分解得到耦合的面积-容量替换,给出精确的四变量高度展开,并证明长度半径由分母分支最小值决定。

Comments 35 pages, two figures

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AI中文摘要

我们研究同时由适当面积和蓄水容量细化的Dyck路径,其中蓄水容量是在路径上方及其晶格路径上壳下方测量的。枚举中使用的有限高度成分是经典的有界高度面积多项式和连分式对象。上壳分解产生一个耦合的面积-容量替换,给出了精确的四变量高度展开,其分母分支由高度水平索引。完整生成函数在两个权重下不对称,而高度加和在面积和容量权重互换下允许对称的未约化分母表示。在开正方形$0<p,q<1$中,我们证明$G(x,1,p,q)$的长度半径是正实数分母分支的最小值。证明结合了该第一分支以下高度展开的一致正态收敛、分支位置的Perron根表示以及加权路径谱半径的区间对数子模性定理。在对角线$p=q=s$上,经典的Chebyshev特化给出了显式的分支交叉和$(1-s)^{2/3}$的分支包络累积律在Dyck临界点处。

英文摘要

We study Dyck paths refined simultaneously by proper area and water capacity, where water capacity is measured above the path and below its lattice-path upper hull. The finite-height ingredients used in the enumeration are classical bounded-height area-polynomial and continued-fraction objects. The upper-hull decomposition produces a coupled area--capacity substitution, which gives an exact four-variable height expansion with denominator branches indexed by the height levels. The full generating function is asymmetric in the two weights, while the height summands admit a symmetric unreduced denominator representation under interchange of the area and capacity weights. In the open square $0<p,q<1$, we prove that the length radius of $G(x,1,p,q)$ is the minimum of the positive real denominator branches. The proof combines uniform normal convergence of the height expansion below this first branch with a Perron-root representation of the branch locations and an interval log-submodularity theorem for spectral radii of weighted paths. On the diagonal $p=q=s$, the classical Chebyshev specialisation gives explicit branch crossings and a $(1-s)^{2/3}$ branch-envelope accumulation law at the Dyck critical point.

2606.08830 2026-06-09 hep-ph nucl-th 新提交

Nuclear parton distributions and nuclear shadowing

核子部分子分布与核阴影效应

Petja Paakkinen, Vadim Guzey

AI总结 综述核子部分子分布函数(PDFs)的物理与唯象学,聚焦小x区域的核阴影效应,总结实验证据、理论解释及全局数据提取,并展望未来精确研究。

Comments 21 pages, 8 figures; a contribution to the Encyclopedia of Nuclear Physics

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AI中文摘要

在这篇贡献中,我们回顾了核子部分子分布函数(PDFs)的物理与唯象学,特别关注核阴影的小x区域。我们总结了PDFs核修正的实验证据并讨论了其理论解释;特别是,我们对比了不同的核阴影模型。我们还概述了从硬过程与原子核的全局数据中进行的模型无关的核PDFs提取,强调了共线因子化的有效性和领先阶核PDFs的主导地位。最后,我们讨论了当前和未来核PDFs与小x QCD动力学精确研究的前景,包括大型强子对撞机重离子超周边碰撞中的光核反应以及未来电子-离子对撞机上的轻子-原子核深度非弹性散射。

英文摘要

In this contribution, we review the physics and phenomenology of nuclear parton distribution functions (PDFs), with a particular focus on the small-x region of nuclear shadowing. We summarise experimental evidence for nuclear modifications of PDFs and discuss their theoretical explanations; in particular, we contrast different models of nuclear shadowing. We also overview model-agnostic extractions of nuclear PDFs from global data on hard processes with nuclei, emphasizing the validity of collinear factorization and the dominance of leading-twist nuclear PDFs. Finally, we discuss perspectives for present and future precision studies of nuclear PDFs and small-x QCD dynamics, including photonuclear reactions in heavy-ion ultraperipheral collisions at the Large Hadron Collider and lepton-nucleus deep inelastic scattering at the future Electron-Ion Collider.

2606.08829 2026-06-09 cs.IT math.IT 新提交

Flexible Coupler Antenna Enhanced Wireless Communication: Modeling and Coupler Position Optimization

柔性耦合天线增强无线通信:建模与耦合器位置优化

Xiaodan Shao, Chuangye Shan, Yunlong Du, Junling Li, Rui Zhang, Cheng-Xiang Wang

AI总结 提出柔性耦合天线(FCA),通过移动无源耦合元件实现机械波束赋形,降低天线和射频链成本,并优化耦合器位置以最大化接收信噪比。

Comments 13 pages

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AI中文摘要

本文提出一种新型柔性耦合天线(FCA),该天线将无源耦合元件围绕固定位置的有源天线移动,以重塑无源元件上的感应电流进行辐射。通过仅移动无源耦合元件而保持有源天线静止,实现了一种新的机械波束赋形形式。所提出的设计显著降低了传统有源阵列波束赋形的天线和射频(RF)链成本,同时具有较低的机械控制复杂度和能耗。为了便于说明,我们考虑一个点对点通信系统,其中发射端有一个FCA,接收端有一个固定天线。具体地,基于多端口电路理论,我们建立了视距(LoS)和多径信道模型,并推导了无源耦合器的机械波束赋形权重作为其位置的函数。然后,我们提出一个新问题,通过优化发射端无源耦合器的位置来最大化接收信噪比(SNR),同时满足耦合器移动和发射功率约束。求解该问题本质上是困难的,因为耦合信道和机械波束赋形在目标函数中引入了非线性。为了解决这个问题,我们提出了一种高效的块坐标条件梯度方法,通过迭代方式依次优化每个耦合器的位置(固定其他耦合器的位置)来搜索所有无源耦合器的最佳位置。仿真结果表明,所提出的系统在可达速率方面显著优于基准方案,但大大减少了有源天线和射频链的数量。

英文摘要

This paper proposes a novel flexible coupler antenna (FCA) that translates passive coupling elements around a fixed-position active antenna to reshape the induced currents on the passive elements for radiation. A new form of mechanical beamforming is achieved by moving only the passive coupling elements while keeping the active antenna stationary. The proposed design significantly reduces the antenna and radio-frequency (RF) chain costs of conventional active array beamforming with low mechanical control complexity and energy consumption. For the purpose of exposition, we consider a point-to-point communication system with one FCA at the transmitter and one fixed antenna at the receiver. Specifically, based on multi-port circuit theory, we establish both the line-of-sight (LoS) and multipath channel models and derive the mechanical beamforming weights of the passive couplers as functions of their positions. Then, we formulate a new problem to maximize the received signal-to-noise ratio (SNR) by optimizing the positions of passive couplers at the transmitter, subject to coupler movement and transmit power constraints. Solving the resulting problem is inherently difficult because coupled channel and mechanical beamforming create non-linearity in the objective function.To tackle this problem, we propose an efficient block-coordinate conditional gradient method to search for the best positions of all passive couplers by sequentially optimizing the position of each coupler with those of the other couplers fixed in an iterative manner.Simulation results demonstrate that the proposed system significantly outperforms benchmark schemes in terms of achievable rate, but with significantly reduced active antennas and RF chains.

2606.08827 2026-06-09 physics.plasm-ph 新提交

High-dimensional inverse design of inertial fusion implosions via differentiable simulation

通过可微模拟实现惯性聚变内爆的高维逆设计

A. J. Crilly, P. Travis, J. P. Brodrick, J. B. Coughlin, A. S. Joglekar

AI总结 提出可微模拟方法,通过自动微分提供梯度,优化惯性约束聚变内爆中500维激光脉冲参数,实现近等熵上升,加速设计空间探索。

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AI中文摘要

惯性约束聚变内爆设计需要在高维设计空间中同时优化强耦合的靶丸和驱动参数。现有的自动化设计方法通常将不可微的辐射流体力学代码视为黑箱,随着维度增加,优化成本急剧上升。本文提出了一种可微模拟方法,用于惯性约束聚变内爆的高维逆设计。通过一个由外部压力脉冲驱动的可微内爆物理模型,自动微分提供了内爆目标相对于设计参数的梯度,从而实现基于梯度的优化。该框架应用于25 kJ OMEGA尺度直接驱动内爆,优化了跨越采样靶丸几何的500维激光脉冲。优化后的脉冲恢复了近等熵上升至峰值功率,而无需预先施加该结构。此外,还探索了神经网络脉冲参数化作为加速设计空间探索的手段。这些结果确立了可微内爆建模作为ICF设计的有前途工具,同时激励了关于伴随鲁棒性和更高保真度可微模拟器的进一步工作。

英文摘要

Inertial confinement fusion implosion design requires simultaneous optimisation of strongly coupled target and driver parameters across high-dimensional design spaces. Existing automated design approaches typically rely on non-differentiable radiation-hydrodynamics codes treated as black boxes, making optimisation increasingly expensive as dimensionality grows. In this work, we present a differentiable simulation approach for high-dimensional inverse design of inertial confinement fusion implosions. Automatic differentiation through a differentiable implosion physics model, driven by an external pressure pulse, provides gradients of implosion objectives with respect to design parameters, enabling gradient-based optimisation. The framework is applied to 25 kJ OMEGA-scale direct-drive implosions, optimising 500-parameter laser pulses across sampled target geometries. The optimised pulse recovers a near-isoentropic rise to peak power without that structure being imposed. Neural-network pulse parameterisations are additionally explored as a means of accelerating design-space exploration. These results establish differentiable implosion modelling as a promising tool for ICF design, while motivating further work on adjoint robustness and higher-fidelity differentiable simulators.

2606.08825 2026-06-09 physics.chem-ph q-bio.MN 新提交

When Three-Dimensional Conformer Ensembles Improve Molecular Property Prediction Beyond Two-Dimensional Fingerprints: A Systematic Study

当三维构象集成超越二维指纹图谱改善分子性质预测时:一项系统研究

Bryan Cheng, Austin Jin, Jasper Zhang

AI总结 通过约1000次实验,系统发现分布核算子提取的构象集成统计量在溶剂化相关性质上显著降低RMSE(如ESOL -11.0%),而对电子或空间任务无益,并揭示了物理基础而非统计原因,建立了四层性能层次。

Comments 10 pages, 4 figures, ACM-BCB 2026 Full Paper

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AI中文摘要

何时三维构象集成能超越二维指纹图谱改善分子性质预测?我们提供了首个系统性的、基于机理的答案。通过跨越MoleculeNet、QM9和MARCEL基准的13种模型配置、14个回归目标和2个分类目标的约1000次实验,我们发现了选择性互补性:通过分布核算子(DKOs)提取的构象集成统计量在溶剂化依赖性质上产生统计显著的RMSE降低(ESOL -11.0%,p < 10^{-9};FreeSolv -13.5%,p < 3×10^{-5};10种子配对验证),而对电子或空间任务无益。三条证据证实这种选择性具有物理而非统计基础:在骨架划分下改进大于随机划分(ESOL上+11.9% vs. +8.5%),集中于大而灵活的分子(最重四分位数+18.9%),并随训练数据单调增长。我们建立了四层性能层次:端到端3D GNN(SchNet, PaiNN;比指纹图谱高21-42%)≥ 工程化物理化学描述符(PMI/SASA/USR)> Morgan指纹图谱+XGBoost > 所有神经构象集成方法,由两种架构不同的GNN确认,并揭示了预计算特征瓶颈限制了集成方法。特征归因和互信息分析揭示了机理不对称性:构象均值特征每特征携带的信息量是指纹图谱位的2-8倍,而协方差特征贡献不到模型信号的2%,解释了为何五个简单标量不变量优于所有复杂协方差架构(p < 0.001)。这些发现产生了经验性质分类和实用的决策框架,用于判断何时构象生成值得投入。

英文摘要

When do three-dimensional conformer ensembles improve molecular property prediction beyond two-dimensional fingerprints? We provide the first systematic, mechanistically grounded answer. Through ~1,000 experiments spanning 13 model configurations, 14 regression targets, and 2 classification targets across MoleculeNet, QM9, and MARCEL benchmarks, we discover selective complementarity: conformer ensemble statistics extracted via Distribution Kernel Operators (DKOs) yield statistically significant RMSE reductions on solvation-dependent properties (ESOL -11.0%, p < 10^{-9}; FreeSolv -13.5%, p < 3x10^{-5}; 10-seed paired validation) while providing no benefit for electronic or steric tasks. Three lines of evidence confirm this selectivity has a physical rather than statistical basis: improvement is larger under scaffold splits than random splits (+11.9% vs. +8.5% on ESOL), concentrates on large, flexible molecules (+18.9% for heaviest quartile), and grows monotonically with training data. We establish a four-tier performance hierarchy: end-to-end 3D GNNs (SchNet, PaiNN; 21-42% over fingerprints) >= engineered physicochemical descriptors (PMI/SASA/USR) > Morgan fingerprints + XGBoost > all neural conformer ensemble methods, confirmed by two architecturally diverse GNNs and revealing that the pre-computed feature bottleneck limits ensemble approaches. Feature attribution and mutual information analysis expose the mechanistic asymmetry: conformer mean features carry 2-8x more information per feature than fingerprint bits, yet covariance features contribute <2% of model signal, explaining why five simple scalar invariants outperform all complex covariance architectures (p < 0.001). These findings yield an empirical property taxonomy and a practical decision framework for when conformer generation is worth the investment.

2606.08824 2026-06-09 cs.SE 新提交

Syntax-driven Incremental Program Verification of Matching Logic Properties

匹配逻辑属性的语法驱动增量程序验证

Domenico Bianculli, Antonio Filieri, Carlo Ghezzi, Dino Mandrioli, Alessandro Maria Rizzi

AI总结 提出一种基于语法-语义框架的增量验证方法,通过算子优先级文法和合成属性模式实现代码变更后仅重验证受影响部分,原型工具实验表明该方法不降低形式验证效率,且根据注解类型和变更位置可优于完全重验证。

Comments 60 pages

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AI中文摘要

增量性是掌握大型、长期软件系统复杂性的基本设计原则。该原则已被敏捷开发过程所采纳,并成为持续软件演化的基础。在此背景下,一个主要挑战是在每次变更后增量地重新验证软件工件的正确性,仅将验证工作集中在受变更影响的部分。我们提出了一种针对用KernelC编写、以匹配逻辑属性注释的程序的增量验证方法。该方法基于一个语法-语义框架,能够隔离分析代码块,使得在程序片段变更后,仅重新处理语义受变更影响的部分。这一性质通过用算子优先级文法表达语言语法,并通过合成属性模式形式化其语义而获得。我们已在原型工具中实现了该技术,并实验评估了其有效性。结果表明,我们的方法不会损害形式验证的效率,并且根据注解的存在和类型以及变更位置和程序结构,可以优于变更后的程序完全重验证。

英文摘要

Incrementality is a fundamental design principle to master the complexity of large, long-lived software systems. This principle has been embraced by agile development processes and it lays at the base of continuous software evolution. A major challenge in this context is to incrementally re-verify the correctness of software artifacts after every change, focusing the verification efforts only on the parts affected by the change. We present an approach to the incremental verification of programs written in KernelC, annotated with properties expressed in matching logic. The approach is based on a syntactic-semantic framework that enables analyzing code chunks in isolation so that, after a change to a program fragment, only the part whose semantics is affected by the change is re-processed. This property is obtained by expressing the language syntax through an operator precedence grammar and by formalizing its semantics through a synthesized attribute schema. We have implemented our technique in a prototype tool and experimentally evaluated its effectiveness. The results show that our approach does not penalize the efficiency of formal verification and can outperform program re-verification after changes, depending on the presence and type of annotations, as well as the position of the change and the program structure.

2606.08823 2026-06-09 nlin.SI 新提交

Geometric curve flows in the plane and mKdV loop solutions

平面中的几何曲线流与mKdV环解

Stephen C. Anco, Jaskaran Maan

AI总结 本文通过简单求积公式推导并详细研究了mKdV行波对应的几何曲线流,分为平移环和旋转环两类,并刻画了闭环存在的条件。

Comments 59 pages; 39 figures

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AI中文摘要

欧几里得平面中的几何曲线流与修正Korteweg-de Vries (mKdV) 方程的解之间存在众所周知的对应关系。对于每种类型的mKdV行波,本文通过一个简单的求积公式推导出相应的几何曲线流,并进行了详细研究。这些曲线流可分为两大类:平移环和旋转环。平移环源于mKdV孤子、cnoidal (Jacobi cn) 波和dnoidal (Jacobi dn) 波,后者是周期性的。旋转环包括从非零背景上的mKdV孤立波和mKdV有理波获得的渐近圆形环,以及由mKdV有理椭圆 (cn 和 dn) 波产生的周期性环。周期环的一个特例(包括开环和闭环)被证明可产生有理余弦环。对每种类型的曲线流进行了显式描述,以刻画其主要特征,包括闭环存在的条件。

英文摘要

There is a well known correspondence between geometric curve flows in the Euclidean plane and solutions of the modified Korteweg-de Vries (mKdV) equation. For each type of mKdV travelling wave, the resulting geometric curve flows are derived here through a simple quadrature formula and studied in detail. These curve flows can be divided into two broad types: travelling loops, and rotating loops. Travelling loops are shown to arise from mKdV solitons, cnoidal (Jacobi cn) and dnoidal (Jacobi dn) waves, the latter being periodic. Rotating loops comprise asymptotically circular ones that are obtained from both mKdV solitary waves on a non-zero background and mKdV rational waves, as well as periodic ones that are produced by mKdV rational elliptic (cn and dn) waves. A specialization of periodic loops, both open and closed, is shown to yield rational cosine loops. An explicit description of each of these types of curve flows is used to characterize their main features, including the condition under which closed loops exist.

2606.08822 2026-06-09 cs.CE 新提交

Unstructured Mesh Tools for Fusion Energy System Design

用于聚变能源系统设计的非结构化网格工具

Mark S. Shephard, Jacob S. Merson, Onkar Sahni, Cameron W. Smith, Usman Riaz, Fuad Hasan, Aditya Y. Joshi, Dhyanjyoti D. Nath, Abhiyan Paudel

AI总结 本文探讨如何利用非结构化网格技术构建仿真工作流,以整合现有聚变研究代码与商业CAE软件,解决几何建模、物理-工程耦合及粒子-连续介质建模耦合等挑战。

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AI中文摘要

执行聚变能源系统的精确仿真需要适当表示关键组件几何形状,以及将复杂的聚变物理代码彼此之间以及与工程分析工具进行耦合。本文研究了创建仿真工作流的挑战,这些工作流充分利用现有聚变研究代码,同时将其与商业计算机辅助工程(CAE)软件集成。涉及的关键领域包括:(a)构建和分析几何形状的网格划分,充分利用可用的几何建模和网格划分技术;(b)聚变物理与工程分析代码的有效耦合;(c)支持耦合粒子与连续介质建模方法的仿真工作流。

英文摘要

The execution of accurate simulations of fusion energy systems requires the appropriate representation of critical component geometries as well as the coupling of complex fusion physics codes with one another and with engineering analysis tools. This paper examines the challenges of creating simulation workflows that fully leverage existing fusion research codes while integrating them with commercial computer-aided engineering (CAE) software. Key areas addressed include: (a) the construction and meshing of analysis geometries taking full advantage of available geometric modeling and meshing technologies; (b) the effective coupling of fusion physics and engineering analysis codes; and (c) the support for simulation workflows that couple particle and continuum modeling methods.

2606.08821 2026-06-09 math.AT math.MG 新提交

Square Metric Spaces

平方度量空间

Charles Fanning, Mehmet Aktas

AI总结 通过等价关系恢复度量空间的坐标结构,刻画有限积或幂表示的存在性,证明等价关系数据精确保持有序坐标信息,并应用于持久同调。

Comments 60 pages, 7 figures

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AI中文摘要

度量空间的乘积分解由坐标映射构建,但这些映射并不包含在结果度量空间中。我们通过等价关系恢复缺失的坐标结构,其类为候选坐标纤维,所得商度量重构坐标因子。该框架精确刻画了度量空间何时具有有限积或幂表示。我们证明了一个范畴等价,表明这些等价关系数据精确保持幂表示的有序坐标信息。对于具有适当$\ell^\infty$-素因子分解的空间,我们使用素重数确定根的存在性和分类。我们还研究了满足$X\cong X\times_\infty X$的度量空间,其中重复坐标分裂给出由无限二进制序列索引的度量商族。我们证明这些二叉树结构精确刻画了满足$X\cong X\times_\infty X$的度量空间。作为持久同调的应用,我们展示了如何恢复其乘积或幂构成给定区间空间的过滤参数。

英文摘要

Product decompositions of metric spaces are built from coordinate maps, but these maps are not part of the resulting metric space. We recover this missing coordinate structure through equivalence relations whose classes are candidate coordinate fibers, and the resulting quotient metrics reconstruct the coordinate factors. This framework characterizes exactly when a metric space admits a finite product or power presentation. We prove an equivalence of categories showing that these equivalence-relation data preserve exactly the ordered coordinate information of power presentations. For spaces with suitable $\ell^\infty$-prime factorizations, we use prime multiplicities to determine the existence and classification of roots. We also study metric spaces satisfying $X\cong X\times_\infty X$, where repeated coordinate splitting gives a family of metric quotients indexed by infinite binary sequences. We prove that these binary tree structures exactly characterize metric spaces satisfying $X\cong X\times_\infty X$. As an application to persistent homology, we show how to recover filtration parameters whose products or powers form a given space of intervals.

2606.08820 2026-06-09 cond-mat.mtrl-sci 新提交

Chiral Surface Phonons

手性表面声子

Mike Pols, Nicola A. Spaldin

AI总结 通过对称性分析和密度泛函理论,证明所有晶体材料表面都存在手性表面声子,并发现这些声子在AB岩盐化合物中产生面内磁性。

Comments 6 pages, 5 figures

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AI中文摘要

我们利用对称性论证结合密度泛函理论证明,晶体材料的所有表面都存在手性表面声子。作为模型系统,我们研究了高对称性AB岩盐化合物的薄板,并发现了原子位移呈现手性运动的表面局域声子。我们进一步证明,这些手性表面声子在表面产生面内磁性层。我们的结果表明,由于表面或界面处对称性降低,手性声子可以在所有晶体材料中出现。这些发现确立了表面作为先前被忽视的手性声子及其相关磁矩的来源,这可能在一系列表面敏感测量中发挥作用。

英文摘要

We use symmetry arguments combined with density functional theory to demonstrate that all surfaces of crystalline materials host surface phonons that are chiral. As model system, we study slabs of highly symmetric AB rocksalt compounds, and find surface-localized phonons whose atomic displacements exhibit chiral motion. We further show that these chiral surface phonons generate sheets of in-plane magnetism at the surface. Our results reveal that chiral phonons can emerge in all crystalline materials as a result of reduced symmetry at surfaces or interfaces. These findings establish surfaces as a previously overlooked source of chiral phonons and their associated magnetic moments, which could play a role in a broad range of surface-sensitive measurements.

2606.08819 2026-06-09 stat.ME 新提交

Model Selection for SLOPE Models: A Bayesian Perspective

SLOPE模型的模型选择:贝叶斯视角

Fabio Feser, Marina Evangelou

AI总结 提出贝叶斯方法BGSLOPE和BSGS,通过嵌入spike-and-slab框架控制FDR,并引入两步正交变换TSO,在合成和真实数据中优于交叉验证等方法。

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AI中文摘要

排序$\ell_1$惩罚估计(SLOPE)模型执行变量或组选择,在已知噪声的正交设置下控制错误发现率(FDR),但这种设置在现实中很少见。在一般条件下,交叉验证是SLOPE的默认模型选择方法,但它针对预测性能而非FDR控制。我们通过提出新的贝叶斯方法——贝叶斯组SLOPE(BGSLOPE)和贝叶斯稀疏组SLOPE(BSGS),填补了SLOPE模型家族的这一空白。BGSLOPE和BSGS将基于组的SLOPE模型嵌入spike-and-slab框架,其中BSGS为稀疏组模型提供了连续的spike-and-slab框架。我们进一步引入两步正交(TSO),将一般设置转换为正交设置,以恢复SLOPE的FDR控制特性。通过广泛的合成和真实数据研究,比较SLOPE模型的所有主要模型选择策略,所提出的贝叶斯模型一致地控制FDR,实现更高的功效,并在预测中优于竞争方法。

英文摘要

Sorted $\ell_1$ Penalized Estimation (SLOPE) models, that perform either variable or group selection, control the false discovery rate (FDR) under orthogonal settings with known noise, but such settings are rare in practice. Under general conditions, cross-validation is the default model selection approach for SLOPE, yet it targets predictive performance rather than FDR control. We address this gap for the SLOPE family of models by proposing new Bayesian approaches, Bayesian Group SLOPE (BGSLOPE) and Bayesian Sparse-group SLOPE (BSGS). BGSLOPE and BSGS embed group-based SLOPE models into a spike-and-slab framework, with BSGS providing a continuous spike-and-slab framework for sparse-group models. We further introduce Two-step Orthogonal (TSO), which transforms a general setting into an orthogonal one to recover SLOPE's FDR control properties. Through extensive synthetic and real data studies comparing all major model selection strategies for SLOPE models, the proposed Bayesian models consistently control FDR, achieve higher power, and outperform competing methods in prediction.

2606.08818 2026-06-09 math-ph math.MP 新提交

Clapeyron-type theorems in nonlinear elasticity

非线性弹性力学中的克拉珀龙型定理

Yury Grabovsky, Lev Truskinovsky

AI总结 推导了经典克拉珀龙定理的非线性类比,通过部分变分对称性(如尺度不变性)得到结合物理力和构型力功的广义关系,并给出非线性弹性问题中的示例。

Comments arXiv admin note: substantial text overlap with arXiv:2508.12441

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AI中文摘要

经典线性弹性力学的克拉珀龙定理提供了一种方法,通过边界上施加的力的功来显式表达平衡构型中存储的能量。我们推导了几个新的积分关系,这些关系可以视为该经典结果的非线性类比,并将其重新解释为变分法中相当一般的陈述。这些关系反映了拉格朗日函数的特定性质,我们称之为“部分变分对称性”,因为它们比经典变分对称性更一般。在非线性弹性力学的框架下,部分变分对称性(例如尺度不变性或尺度齐次性)通过诺特分析导致了克拉珀龙定理的不同非线性推广,这些推广自然地结合了物理力和构型力的功。我们给出了一系列具有启发性的例子,展示了所获得的一般结果在不同非线性弹性问题中的有效性。

英文摘要

Clapeyron's Theorem of classical linear elasticity provides a way to explicitly express the energy stored in an equilibrium configuration in terms of the work of the forces applied on the boundary. We derive several new integral relations which can be viewed as nonlinear analogs of this classical result, reinterpreting them as rather general statements within Calculus of Variations. These relations reflect specific properties of Lagrangians, that we call ``partial variational symmetries'', since they are more general than classical variational symmetries. In the framework of nonlinear elasticity, partial variational symmetries, such as scale invariance, or scaling homogeneity, lead, via Noether's analysis to different nonlinear generalizations of Clapeyron's Theorem that combine naturally the work of physical and configurational forces. We present a series of illuminating examples showing the effectiveness of the obtained general results in different problems of nonlinear elasticity.

2606.08817 2026-06-09 math.NA cs.NA 新提交

Low-Variance Randomised Numerical Linear Algebra for Finite Element Simulation

有限元模拟的低方差随机数值线性代数方法

N. Polydorides, Y. Wu, . H. Noori, H. Vandierendonck, R. Woods

AI总结 针对参数化椭圆PDE的多查询有限元系统,提出结合Galerkin子空间投影、参数无关杠杆分数伯努利采样和控制变量的低方差随机数值线性代数方法,降低计算成本并保持精度。

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AI中文摘要

我们提出了一种低方差随机数值线性代数方法,用于处理参数化椭圆偏微分方程的多查询有限元系统,应用于数字孪生和在线模型校准。该方法依赖于Galerkin子空间投影来降低维度,然后将参数无关的杠杆分数伯努利采样与控制变量方案相结合,生成低方差的“正向”草图和可逆的“逆”草图,然后融合成一个单一高效的正则化估计器。这有效地降低了计算投影方程组时的计算成本,同时保留了底层有限元公式的结构、稳定性和精度。我们推导了草图误差、可逆性和估计器方差的概率界,然后在大型示例问题上验证了该方法。结果表明,当参数场变化不太剧烈时,控制变量与草图融合的协同作用可以很大程度上抵消次优参数无关采样造成的损失。在这种情形下,我们的方法在时间、内存和通信方面实现了显著的节省,同时保持了科学模拟可接受的精度水平。

英文摘要

We present a low-variance randomised numerical linear algebra approach for multi-query finite element systems arising from parametric elliptic partial differential equations with applications to digital twins and online model calibration. The method relies on Galerkin subspace projection for reducing the dimensionality, and then combines parameter-oblivious leverage-score Bernoulli sampling with a control variates scheme to yield a reduced-variance `forward' sketch and an invertible `inverse' sketch that are then fused to a single efficient regularised estimator. Effectively, this reduces the computational cost in computing the projected system of equations while preserving the structure, stability, and accuracy of the underlying FEM formulation. We derive probabilistic bounds for the sketching error, invertibility, and estimator variance, and then validate the method on large-scale example problems. The results show that when the parameter fields do not vary too sharply, the synergy of control variates together with the sketch fusion can largely offset the loss incurred by the sub-optimal parameter-oblivious sampling. In this regime, our method achieves substantial savings in time, memory, and communication while maintaining accuracy levels that are acceptable for scientific simulation.

2606.08812 2026-06-09 physics.med-ph 新提交

Investigating the Uncertainty of Cellular Microenvironment Parameter Estimations via Diffusion MRI Cytometry

通过扩散MRI细胞计量学探究细胞微环境参数估计的不确定性

Wen Li, Yan Dai, Arely Perez Rodriguez, Todd Aguilera, Jie Deng, Xun Jia

AI总结 本研究利用IMPULSED扩散MRI信号,通过雅可比敏感性分析和神经网络映射,识别出细胞直径、细胞内体积分数和细胞外扩散系数可稳健估计,为放疗反应监测提供无创评估框架。

Comments 34 pages, 5 figures

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AI中文摘要

本研究旨在识别可从IMPULSED扩散MRI信号中稳健估计的细胞微环境参数,并开发可靠的基于映射的估计框架。使用已建立的IMPULSED模型模拟扩散MRI信号,该模型包含一个脉冲梯度自旋回波序列和两个不同频率的振荡梯度自旋回波序列。考虑了五个细胞参数:细胞直径($d$)、细胞内扩散系数($D_{in}$)、细胞内体积分数($V_{in}$)、细胞外扩散系数($D_{ex}$)以及$D_{ex}$的频率依赖斜率($β_{ex}$)。在信噪比为30(代表1.5T MRI扫描仪上临床可实现的条件)下,使用基于雅可比矩阵的敏感性分析量化参数不确定性。为了实现直接参数映射,对信号进行对数变换,使用主成分分析降维,然后通过线性回归、四阶多项式回归和全连接四层神经网络估计参数。使用MC38细胞系进行体外模型验证。不确定性分析确定$d$、$V_{in}$和$D_{ex}$为可稳健推导的参数,每个参数的相对不确定性低于1.0。在测试的模型中,四层神经网络表现最佳,$d$的平均绝对误差为1.7 $μ$m,$V_{in}$为5.06%,$D_{ex}$为0.28 $μ$m$^2$/ms。体外验证显示细胞直径估计误差为6.7%。这些结果表明,IMPULSED dMRI可以支持对关键细胞微环境参数的稳健估计,并为放疗反应监测期间肿瘤微环境变化的无创评估提供实用框架。

英文摘要

This study aims to identify cell microenvironment parameters that can be robustly estimated from IMPULSED diffusion MRI signals and to develop a reliable mapping-based estimation framework. Diffusion MRI signals were simulated using the established IMPULSED model with one pulsed gradient spin echo sequence and two oscillating gradient spin echo sequences at different frequencies. Five cellular parameters were considered: cell diameter ($d$), intracellular diffusion coefficient ($D_{in}$), intracellular volume fraction ($V_{in}$), extracellular diffusion coefficient ($D_{ex}$), and the frequency-dependent slope of $D_{ex}$ ($β_{ex}$). Parameter uncertainty was quantified using Jacobian-based sensitivity analysis at an SNR of 30, representing clinically achievable conditions on a 1.5T MRI scanner. To enable direct parameter mapping, signals were logarithmically transformed, reduced in dimension using principal component analysis, and then used to estimate parameters with linear regression, fourth-order polynomial regression, and a fully connected four-layer neural network. Model validation was performed in vitro using MC38 cell lines. Uncertainty analysis identified $d$, $V_{in}$, and $D_{ex}$ as robustly derivable parameters, each with relative uncertainty below 1.0. Among the tested models, the four-layer neural network performed best, with mean absolute errors of 1.7 $μ$m for $d$, 5.06% for $V_{in}$, and 0.28 $μ$m$^2$/ms for $D_{ex}$. In vitro validation showed a 6.7% error in cell diameter estimation. These results demonstrate that IMPULSED dMRI can support robust estimation of key cell microenvironment parameters and provide a practical framework for noninvasive assessment of tumor microenvironment changes during radiation therapy response monitoring.

2606.08811 2026-06-09 cs.DB 新提交

Data Architectures and their Technical Requirements (DATER)

数据架构及其技术需求(DATER)

Sayed Hoseini, Christoph Quix, Stefan Decker

AI总结 本文提出DATER概念框架,系统描述和评估六种现代数据架构(数据仓库、语义数据湖、数据湖仓、数据编织、数据网格)的技术需求,帮助研究者与实践者理解架构范式、重叠与适用场景。

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AI中文摘要

现代组织高速生成和消费大量异构数据,这需要持续开发新技术以实现更高效、可靠的数据管理。因此,设计合适的数据架构已成为战略需求,因为它们决定了数据如何集成、治理以及用于分析和决策。本文引入了一个概念框架——数据架构及其技术需求(DATER)——以基于技术需求系统地描述和评估数据架构。研究了六种现代架构:数据仓库、(语义)数据湖、数据湖仓、数据编织和数据网格。每种架构都通过历史背景、定义特征以及对DATER维度的符合性进行分析。该研究支持研究人员和实践者导航架构范式,澄清重叠,并突出优势、局限性和用例适用性。

英文摘要

Modern organizations generate and consume massive volumes of heterogeneous data at high speed. This requires a continuous development of new techniques for more efficient and reliable data management. Designing appropriate data architectures has therefore become a strategic necessity, as they shape how data is integrated, governed, and made available for analytics and decisionmaking. This paper introduces a conceptual framework - Data Architectures and their Technical Requirements (DATER) - to systematically describe and evaluate data architectures based on technical requirements. Six modern architectures are examined: data warehouse, (semantic) data lake, data lakehouse, data fabric, and data mesh. Each is analyzed by historical context, defining features, and conformance to DATER dimensions. The study supports researchers and practitioners in navigating architectural paradigms, clarifying overlaps, and highlighting strengths, limitations, and use-case suitability.

2606.08809 2026-06-09 math.CO 新提交

A complete characterization of a family of permutation trinomials over $\mathbb F_{p^2}$

$\mathbb F_{p^2}$上一类置换三项式的完整刻画

Marco Timpanella

AI总结 本文完整刻画了形如$f_{λ_1,λ_2}(x)=x^{p^2-p+1}+λ_1x^{p^2}+λ_2x^{2p-1}$的多项式为$\mathbb F_{p^2}$上置换多项式的所有参数对$(λ_1,λ_2)$,得到三个显式族。

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AI中文摘要

设$p>3$为素数,令$$f_{λ_1,λ_2}(x)=x^{p^2-p+1}+λ_1x^{p^2}+λ_2x^{2p-1}\in\mathbb F_{p^2}[x].$$ 我们确定了所有使得$f_{λ_1,λ_2}$是$\mathbb F_{p^2}$上置换多项式的对$(λ_1,λ_2)\in(\mathbb F_{p^2})^2$。最终分类包含三个显式族。第一个是二项式情形$λ_1=0$。另外两个由条件$λ_2=cλ_1^3$(其中$c\in \mathbb F_{p}^{*}$)得到,并由涉及范数$λ_1^{p+1}$的两个简单方程定义。证明基于AGW准则以及对单位圆$μ_{p+1}$上诱导的有理函数自然关联的四次曲线的研究。

英文摘要

Let $p>3$ be a prime and let $$f_{λ_1,λ_2}(x)=x^{p^2-p+1}+λ_1x^{p^2}+λ_2x^{2p-1}\in\mathbb F_{p^2}[x].$$ We determine all pairs $(λ_1,λ_2)\in(\mathbb F_{p^2})^2$ for which $f_{λ_1,λ_2}$ is a permutation polynomial of $\mathbb F_{p^2}$. The final classification consists of three explicit families. The first one is the binomial case $λ_1=0$. The other two are obtained from the condition $λ_2=cλ_1^3$, with $c\in \mathbb F_{p}^{*}$, and are defined by two simple equations involving the norm $λ_1^{p+1}$. The proof is based on the AGW criterion and on the study of a quartic curve naturally associated with the rational function induced on the unit circle $μ_{p+1}$.

2606.08808 2026-06-09 eess.SY cs.SY 新提交

Energy Storage as a Multi-Use Asset: Applications Across the Power System

储能作为多用途资产:电力系统中的跨应用

Fabrizio Sossan

AI总结 本文提出储能应用的分类法,讨论主要应用领域及整合挑战,并介绍瑞士创新署支持的STORE旗舰项目。

Comments Manuscript submitted to the Grid Services & Markets Conference (GSM 2026)

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AI中文摘要

电力系统的能源转型需要灵活资产来抵消可再生能源发电在多时间尺度上的波动性,同时支持可再生能源整合和需求电气化,而无需昂贵的电网加固。储能资产具有独特地位:根据技术不同,它可以提供高爬坡率的短时电网服务(如频率调节和电压支撑)、更长时功能(如日内削峰)或跨季节能量缓冲。这种多服务特性,加上储能技术(尤其是电池储能系统)成本的下降,是储能投资经济可行性的核心。给定设施的价值强烈依赖于其电网连接点和预期用例:服务于消费者或发电厂的资产耦合电池面临的服务格局和商业模式,与作为独立电网资源的网络耦合系统不同。本文提出了并网储能应用的结构化分类法,讨论了主要应用领域,并描述了将储能有效集成到电力系统中必须解决的关键挑战。特别强调了瑞士监管背景下的服务讨论。最后,介绍了由瑞士创新署(Innosuisse)支持的STORE旗舰项目,该项目旨在解决电网中储能集成的一些关键挑战。

英文摘要

The energy transition in power systems requires flexible assets to offset renewable generation variability across multiple time scales, while supporting the integration of renewables and the electrification of demand without requiring costly grid reinforcement. Energy storage occupies a unique position among these assets: depending on the technology, it can provide short-duration grid services at high ramping rates, such as frequency regulation and voltage support, longer-duration functions such as intra-day peak shaving, or inter-seasonal energy buffering. This multi-service character, combined with the declining costs of energy storage technologies (most notably that of battery energy storage systems), is central to the economic viability of storage investments. The value of a given installation depends strongly on its grid connection point and intended use case: an asset-coupled battery serving a consumer or generation plant faces a different service landscape, and therefore a different business case, than a network-coupled system operating as an independent grid resource. This paper presents a structured taxonomy of grid-connected energy storage applications, discusses the principal application domains, and describes the key challenges that must be addressed to integrate storage effectively into power systems. Services are discussed with special emphasis on the Swiss regulatory context. Finally, the STORE flagship project supported by the Swiss Innovation Agency (Innosuisse), where some of the critical challenges of energy storage integration in power grids are addressed, is introduced.

2606.08807 2026-06-09 cs.CY 新提交

A Classroom Study of LLM-Generated Feedback Intervention in Introductory Programming

LLM生成反馈干预在入门编程中的课堂研究

Hasnain Heickal, Andrew Lan

AI总结 通过随机对照实验,比较自然语言提示、AI生成测试用例和无反馈三种条件,发现自然语言反馈显著提高完成率和收敛速度,而测试用例反馈效果取决于其有效性。

Comments Accepted at IRAISE 2026 (Festival of Learning)

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AI中文摘要

大型语言模型(LLM)越来越多地被用于在入门编程课程中提供自动反馈,然而来自真实课堂部署的比较不同反馈模态的经验证据仍然有限。在这项工作中,我们展示了一项大规模课堂研究,其中通过随机协议在入门Python编程课程中部署了AI生成的反馈。学生对错误提交收到三种反馈条件之一:自然语言提示、AI生成的失败测试用例或无AI反馈。我们发布了由此产生的数据集ProgFeed,该数据集捕获了来自17个实验室的215名同意学生的6,693次提交,包括反馈条件、基于执行的性能指标和细粒度时间信息。利用这些数据,我们分析了学习轨迹、反馈质量和重复尝试中的提交行为。我们发现自然语言反馈与更高的完成率和更快的正确解收敛显著相关。相比之下,测试用例反馈表现出异质性效应,这些效应关键取决于反馈的有效性。我们的结果表明,AI生成反馈的形式很重要,评估反馈质量——而不仅仅是其存在——对于理解其教学影响至关重要。

英文摘要

Large language models (LLMs) are increasingly used to provide automated feedback in introductory programming courses, yet empirical evidence from authentic classroom deployments comparing different feedback modalities remains limited. In this work, we present a large-scale classroom study in which AI-generated feedback was deployed through a randomized protocol in an introductory Python programming course. Students received one of three feedback conditions on incorrect submissions: natural language hints, AI-generated failing test cases, or no AI feedback. We release the resulting dataset, ProgFeed, which captures 6,693 submissions from 215 consenting students across 17 labs, including feedback conditions, execution-based performance measures, and fine-grained temporal information. Using this data, we analyze learning trajectories, feedback quality, and submission behavior over repeated attempts. We find that natural language feedback is significantly associated with higher completion rates and faster convergence to correct solutions. Test case feedback, by contrast, exhibits heterogeneous effects that depend critically on feedback validity. Our results suggest that the form of AI-generated feedback matters, and that evaluating feedback quality -- not just its presence -- is essential for understanding its pedagogical impact.

2606.08805 2026-06-09 cond-mat.dis-nn q-bio.NC 新提交

Predictable Mean-Field Chaos in Random Recurrent Networks

随机循环网络中的可预测平均场混沌

Alkesh Yadav, Vladimir Shaidurov, Jonathan Kadmon

AI总结 本文证明在解析非线性且傅里叶衰减足够快的随机循环网络中,平均场轨迹的过去唯一决定其未来,从而将平均场理论从系综描述转化为单个轨迹的条件预测理论,并引入Krylov增长刻画预测复杂度。

Comments 5 pages, 2 figures, Supplementary material

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AI中文摘要

动态平均场理论将随机循环网络中的确定性混沌重述为一个有效的随机过程。我们证明,对于具有足够快傅里叶衰减的解析非线性,这种随机性只是表象:一个实现平均场轨迹的连续过去唯一地决定了它的未来。因此,平均场理论不仅仅是一个系综描述,而是单个轨迹的条件预测理论。将功率谱展开到Krylov状态空间,揭示了这种潜在确定性如何跨越一个无限时间模式层级进行组织。相关的Krylov增长率设定了有限分辨率预测的复杂度,并给出了这类网络中最大李雅普诺夫指数的上界。因此,微观敏感性和预测复杂度是平均场混沌的不同方面。我们的结果将针对哈密顿混沌动力学发展的Krylov增长思想扩展到经典耗散系统。

英文摘要

Dynamical mean-field theory recasts deterministic chaos in random recurrent networks as an effective stochastic process. We show that for analytic nonlinearities with sufficiently fast Fourier decay, this stochasticity is only apparent: the continuous past of a realized mean-field trajectory uniquely determines its future. The mean-field theory is therefore not merely an ensemble description, but a conditional prediction theory for individual trajectories. Unfolding the power spectrum into a Krylov state space exposes how this latent determinism is organized across an infinite hierarchy of temporal modes. The associated Krylov growth rate sets the complexity of finite-resolution prediction and upper-bounds the largest Lyapunov exponent in this class of networks. Thus, microscopic sensitivity and predictive complexity are distinct aspects of mean-field chaos. Our results extend Krylov growth ideas developed for Hamiltonian chaotic dynamics to classical dissipative systems.