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English: Positional encodings (PEs) are essential for effective graph representation
learning because they provide position awareness in inherently
position-agnostic transformer architectures and increase the expressive
capacity of Graph Neural Networks (GNNs). However, designing powerful and
efficient PEs for graphs poses significant challenges due to the absence of
canonical node ordering and the scale of the graph. {In this work, we identify
four key properties that graph PEs should satisfy}: stability, expressive
power, scalability, and genericness. We find that existing eigenvector-based PE
methods often fall short of jointly satisfying these criteria. To address this
gap, we introduce PEARL, a novel framework of learnable PEs for graphs. Our
primary insight is that message-passing GNNs function as nonlinear mappings of
eigenvectors, enabling the design of GNN architectures for generating powerful
and efficient PEs. A crucial challenge lies in initializing node attributes in
a manner that is both expressive and permutation equivariant. We tackle this by
initializing GNNs with random node inputs or standard basis vectors, thereby
unlocking the expressive power of message-passing operations, while employing
statistical pooling functions to maintain permutation equivariance. Our
analysis demonstrates that PEARL approximates equivariant functions of
eigenvectors with linear complexity, while rigorously establishing its
stability and high expressive power. Experimental evaluations show that PEARL
outperforms lightweight versions of eigenvector-based PEs and achieves
comparable performance to full eigenvector-based PEs, but with one or two
orders of magnitude lower complexity. Our code is available at
https://github.com/ehejin/Pearl-PE.
Chinese: 位置编码（PEs）对于有效的图表示学习至关重要，因为它们在本质上位置无关的Transformer架构中提供了位置感知能力，并增强了图神经网络（GNNs）的表达能力。然而，由于缺乏规范化的节点排序和图的规模，为图设计强大且高效的PEs面临着重大挑战。{在本工作中，我们确定了图PE应满足的四个关键属性：稳定性、表达能力、可扩展性和通用性。}我们发现现有的基于特征向量的PE方法往往难以同时满足这些标准。为弥补这一差距，我们引入了PEARL，一种用于图的可学习PE框架。我们的主要洞见是，消息传递GNNs充当特征向量的非线性映射，从而能够设计出用于生成强大且高效PEs的GNN架构。一个关键挑战在于以既具表达能力又满足置换等变性的方式初始化节点属性。我们通过使用随机节点输入或标准基向量初始化GNNs来解决这个问题，从而释放了消息传递操作的表达能力，同时采用统计池化函数来保持置换等变性。我们的分析表明，PEARL以线性复杂度逼近特征向量的等变函数，同时严格证明了其稳定性和高表达能力。实验评估显示，PEARL优于基于特征向量的PE的轻量级版本，并实现了与完整基于特征向量的PE相当的性能，但复杂度降低了一个或两个数量级。我们的代码可在https://github.com/ehejin/Pearl-PE获取。
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English: We prove that the distributional limit of the normalised number of returns to
small neighbourhoods of periodic points of non-uniformly hyperbolic dynamical
systems is compound Poisson. The returns to small balls around a fixed point in
the phase space correspond to the occurrence of rare events, or exceedances of
high thresholds, so that there is a connection between the laws of Return Times
Statistics and Extreme Value Laws. The fact that the fixed point in the phase
space is a repelling periodic point implies that there is a tendency for the
exceedances to appear in clusters whose average sizes is given by the Extremal
Index, which depends on the expansion of the system at the periodic point.
We recall that for generic points, the exceedances, in the limit, are
singular and occur at Poisson times. However, around periodic points, the
picture is different: the respective point processes of exceedances converge to
a compound Poisson process, so instead of single exceedances, we have entire
clusters of exceedances occurring at Poisson times with a geometric
distribution ruling its multiplicity.
The systems to which our results apply include: general piecewise expanding
maps of the interval (Rychlik maps), maps with indifferent fixed points
(Manneville-Pomeau maps) and Benedicks-Carleson quadratic maps.
Chinese: 我们证明了，对于非一致双曲动力系统中周期点的邻域内正规化返回次数的分布极限是复合泊松分布。在相空间中固定点周围的小球内的返回次数对应于稀有事件的发生或高阈值的超越，因此返回时间统计规律与极值定律之间存在联系。相空间中的固定点是排斥周期点这一事实意味着超越事件倾向于成簇出现，其平均大小由极值指数给出，该指数取决于系统在周期点的扩张性。
我们回顾，对于一般点，在极限情况下，超越事件是奇异的，并以泊松时间发生。然而在周期点附近情况则不同：相应的超越事件点过程收敛于复合泊松过程，因此我们观察到的是整个超越事件簇在泊松时间内发生，其数量分布遵循几何分布。
我们的结果适用于以下系统：区间的一般分段扩张映射（Rychlik映射）、具有非平凡固定点的映射（Manneville-Pomeau映射）以及Benedicks-Carleson二次映射。
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English: We describe methods for the measurement of translational diffusion in very
large static magnetic field gradients by NMR. The techniques use a
"hole-burning" sequence that, with the use of fringe field gradients of 42 T/m,
can image diffusion along one dimension on a submicron scale. Two varieties of
this method are demonstrated, including a particularly efficient mode called
the "hole-comb," in which multiple diffusion times comprising an entire
diffusive evolution can be measured within the span of a single detected slice.
The advantages and disadvantages of these methods are discussed, as well as
their potential for addressing non-Fickian diffusion, diffusion in restricted
media, and spatially inhomogeneous diffusion.
Chinese: 我们描述了通过核磁共振（NMR）在非常大的静态磁场梯度中测量平移扩散的方法。这些技术使用称为“打洞烧灼”序列的方法，通过使用42 T/m的边缘场梯度，可以在亚微米尺度上沿一个维度成像扩散。展示了两种这种方法，包括一种特别有效的方法称为“打洞梳”，在这种方法中，可以测量整个扩散演化的多个扩散时间，仅在一个检测切片的范围内。这些方法的优点和缺点进行了讨论，以及它们在处理非菲克扩散、受限介质中的扩散和空间不均匀扩散方面可能的应用。
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English: In this paper we calculate the Rayleigh-Brillouin spectrum for a relativistic
simple fluid according to three different versions available for a relativistic
approach to non-equilibrium thermodynamics. An outcome of these calculations is
that Eckart's version predicts that such spectrum does not exist. This provides
an argument to question its validity. The remaining two results, which differ
one from another, do provide a finite form for such spectrum. This raises the
rather intriguing question as to which of the two theories is a better
candidate to be taken as a possible version of relativistic non-equilibrium
thermodynamics. The answer will clearly require deeper examination of this
problem.
Chinese: 在本文中，我们根据三种不同的相对论非平衡热力学方法版本，计算了相对论简单流体的瑞利-布里渊谱。这些计算结果表明，埃克哈特版本预测这种谱不存在，这为质疑其有效性提供了论据。其余两个结果虽然彼此不同，但确实为这种谱提供了有限形式。这引发了相当有趣的问题：在相对论非平衡热力学中，哪两种理论更有可能是合适的候选版本。答案显然需要对该问题进行更深入的研究。
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English: ALMA has observed a plethora of ring-like structures in planet forming discs
at distances of 10-100 au from their host star. Although several mechanisms
have been invoked to explain the origin of such rings, a common explanation is
that they trace new-born planets. Under the planetary hypothesis, a natural
question is how to reconcile the apparently high frequency of gap-carving
planets at 10-100 au with the paucity of Jupiter mass planets observed around
main sequence stars at those separations. Here, we provide an analysis of the
new-born planet population emerging from observations of gaps in discs, under
the assumption that the observed gaps are due to planets. We use a simple
estimate of the planet mass based on the gap morphology, and apply it to a
sample of gaps recently obtained by us in a survey of Taurus with ALMA. We also
include additional data from recent published surveys, thus analysing the
largest gap sample to date, for a total of 48 gaps. The properties of the
purported planets occupy a distinctively different region of parameter space
with respect to the known exo-planet population, currently not accessible
through planet finding methods. Thus, no discrepancy in the mass and radius
distribution of the two populations can be claimed at this stage. We show that
the mass of the inferred planets conforms to the theoretically expected trend
for the minimum planet mass needed to carve a dust gap. Finally, we estimate
the separation and mass of the putative planets after accounting for migration
and accretion, for a range of evolutionary times, finding a good match with the
distribution of cold Jupiters.
Chinese: ALMA观测到了在距离其宿主星10-100天文单位处的行星形成盘中大量环状结构。尽管已经提出了几种机制来解释这些环的起源，但一个普遍的解释是它们追踪新生的行星。在行星假说下，一个自然的问题是如何调和在10-100天文单位处观测到的空隙雕刻行星的高频率与在那些距离处观测到的木星质量行星数量稀少之间的矛盾。在这里，我们基于对盘面空隙的观测，假设观测到的空隙是由行星造成的，提供了新生行星种群的分析。我们使用基于空隙形态的简单行星质量估计，并将其应用于我们最近通过ALMA对金牛座进行的调查中获得的空隙样本。我们还包括来自最近发表的调查的附加数据，从而分析了迄今为止最大的空隙样本，共计48个空隙。这些声称的行星的性质与已知的系外行星种群相比，在参数空间中占据一个明显不同的区域，目前这些区域无法通过行星发现方法访问。因此，目前不能声称这两个种群在质量和半径分布上存在差异。我们表明，推断出的行星质量符合理论上预期的最小行星质量趋势，这是雕刻尘埃空隙所需的。最后，我们考虑了迁移和积累后，估计了假想行星的分离和质量，在一系列演化时间范围内，发现与冷木星的分布相匹配。
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English: To determine the state of spin polarization of the 3D electron gas at very
low densities and zero temperature, we calculate the energy versus spin
polarization using Diffusion Quantum Monte Carlo methods with backflow
wavefunctions and twist averaged boundary conditions. We find a second order
phase transition to a partially polarized phase at r_s = 50 \pm 2. The magnetic
transition temperature is estimated using an effective mean field method, the
Stoner model.
Chinese: 为了确定在非常低密度和零温度下3D电子气的自旋极化状态，我们使用具有反流波函数和扭曲平均边界条件的扩散量子蒙特卡罗方法计算能量与自旋极化的关系。我们发现，在r_s = 50 ± 2时，发生二级相变至部分极化相。我们使用有效平均场方法，即Stoner模型，来估计磁转变温度。
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English: We show that, in addition to the counting of canonical dimensions, a counting
of loop orders is necessary to fully specify the power counting of Standard
Model Effective Field Theory (SMEFT). Using concrete examples, we demonstrate
that considering the canonical dimensions of operators alone may lead to
inconsistent results. The counting of both, canonical dimensions and loop
orders, establishes a clear hierarchy of the terms in SMEFT. In practice, this
serves to identify, and focus on, the potentially dominating effects in any
given high-energy process in a meaningful way. Additionally, this will lead to
a consistent limitation of free parameters in SMEFT applications.
Chinese: 我们证明，除了计算规范维数之外，还需要计算圈阶数来完全指定标准模型有效场论（SMEFT）中的幂级数计数。通过具体的例子，我们演示了仅考虑操作符的规范维数可能会导致不一致的结果。同时计算规范维数和圈阶数，可以明确SMEFT中各项的层次关系。在实践中，这有助于识别并集中关注任何给定高能过程中的潜在主导效应。此外，这还将导致在SMEFT应用中对自由参数的一致限制。
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English: Despite their success, Large-Language Models (LLMs) still face criticism as
their lack of interpretability limits their controllability and reliability.
Traditional post-hoc interpretation methods, based on attention and
gradient-based analysis, offer limited insight into the model's decision-making
processes. In the image field, Concept-based models have emerged as
explainable-by-design architectures, employing human-interpretable features as
intermediate representations. However, these methods have not been yet adapted
to textual data, mainly because they require expensive concept annotations,
which are impractical for real-world text data. This paper addresses this
challenge by proposing a self-supervised Interpretable Concept Embedding Models
(ICEMs). We leverage the generalization abilities of LLMs to predict the
concepts labels in a self-supervised way, while we deliver the final
predictions with an interpretable function. The results of our experiments show
that ICEMs can be trained in a self-supervised way achieving similar
performance to fully supervised concept-based models and end-to-end black-box
ones. Additionally, we show that our models are (i) interpretable, offering
meaningful logical explanations for their predictions; (ii) interactable,
allowing humans to modify intermediate predictions through concept
interventions; and (iii) controllable, guiding the LLMs' decoding process to
follow a required decision-making path.
Chinese: 尽管大型语言模型（LLMs）取得了成功，但它们仍然面临批评，因为它们缺乏可解释性，这限制了它们的可控性和可靠性。基于注意力和梯度分析的传统事后解释方法，对模型的决策过程提供了有限的洞察。在图像领域，基于概念的模式作为可解释的设计架构出现，使用人类可解释的特征作为中间表示。然而，这些方法尚未适应文本数据，主要是因为它们需要昂贵的概念标注，这在现实世界的文本数据中是不切实际的。本文通过提出自监督可解释概念嵌入模型（ICEMs）来应对这一挑战。我们利用LLMs的泛化能力以自监督的方式预测概念标签，同时我们通过可解释的函数提供最终的预测。我们实验的结果表明，ICEMs可以通过自监督的方式训练，达到与完全监督的概念基础模型和端到端黑盒模型相似的性能。此外，我们还表明，我们的模型是（i）可解释的，为它们的预测提供有意义的逻辑解释；（ii）可交互的，允许人类通过概念干预修改中间预测；（iii）可控的，引导LLMs的解码过程遵循所需的决策路径。
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English: We present spectroscopic measurements of the Rossiter-McLaughlin effect for
WASP-148b, the only known hot Jupiter with a nearby warm-Jupiter companion,
from the WIYN/NEID and Keck/HIRES instruments. This is one of the first
scientific results reported from the newly commissioned NEID spectrograph, as
well as the second obliquity constraint for a hot Jupiter system with a
close-in companion, after WASP-47. WASP-148b is consistent with being in
alignment with the sky-projected spin axis of the host star, with
$\lambda=-8^{\circ}.2^{{+8^{\circ}.7}}_{-9^{\circ}.7}$. The low obliquity
observed in the WASP-148 system is consistent with the orderly-alignment
configuration of most compact multi-planet systems around cool stars with
obliquity constraints, including our solar system, and may point to an early
history for these well-organized systems in which migration and accretion
occurred in isolation, with relatively little disturbance. By contrast,
previous results have indicated that high-mass and hot stars appear to more
commonly host a wide range of misaligned planets: not only single hot Jupiters,
but also compact systems with multiple super-Earths. We suggest that, to
account for the high rate of spin-orbit misalignments in both compact
multi-planet and isolated-hot-Jupiter systems orbiting high-mass and hot stars,
spin-orbit misalignments may be caused by distant giant planet perturbers,
which are most common around these stellar types.
Chinese: 我们利用WIYN/NEID和Keck/HIRES仪器对唯一已知的带有附近温暖巨行星的热木星WASP-148b进行了光谱测量，揭示了Rossiter-McLaughlin效应。这是新安装的NEID光谱仪的首批科学结果之一，也是继WASP-47之后对带有近距离伴星的热木星系统观测到的第二个轨道倾角限制。WASP-148b与宿主恒星的视旋转轴一致，观测到的倾角为$\lambda=-8^{\circ}.2^{{+8^{\circ}.7}}_{-9^{\circ}.7}$。WASP-148系统的低倾角与围绕较冷恒星的大多数紧凑多行星系统中观测到的有序排列配置一致，包括我们的太阳系，这可能表明这些系统早期的历史中，迁移和吸积在相对不受干扰的情况下独立发生。相比之下，先前的结果表明，高质量和热恒星似乎更常拥有各种不规则排列的行星：不仅单个热木星，还有多个超级地球构成的紧凑系统。我们推测，为了解释围绕高质量和热恒星的紧凑多行星系统和孤立热木星系统中高频率的自转轨道不一致现象，自转轨道不一致可能是由远处的巨型行星扰动引起的，这种扰动在这些恒星类型中最为常见。
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English: The Electric Dipole Moment of the electron (eEDM) is typically investigated
in experiments using paramagnetic molecules. However, the physical observable
in these searches consists in a linear combination of CP-violating
interactions, rather than the eEDM alone, which is commonly referred to as the
equivalent EDM of the system. Assuming the presence of new CP-odd physics from
heavy degrees of freedom, we parameterize its effects within the Standard Model
Effective Field Theory (SMEFT) framework. We systematically compute the
contributions to the full low-energy direction probed by EDM searches, focusing
on leading-order effects at dimension six and one-loop level, while also
discussing selected two-loop and dimension-eight contributions. We find that
eEDM experiments are sensitive to a broader class of SMEFT operators than
previously recognized.
Chinese: 电子的电偶极矩（eEDM）通常在利用顺磁性分子的实验中被研究。然而，在这些搜索中观察到的物理量是由CP破坏相互作用的线性组合构成的，而不是单独的eEDM，这通常被称为系统的等效电偶极矩。假设存在来自重自由度的新的CP奇偶物理，我们在标准模型有效场论（SMEFT）框架内对其效应进行参数化。我们系统地计算了eEDM搜索探测到的全部低能方向的贡献，重点关注六维和一阶循环级别的领先效应，同时也讨论了选定的二阶循环和八维贡献。我们发现，eEDM实验对比之前所认为的，对SMEFT算符的敏感性更广。
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English: In recent research on dialogue systems and corpora, there has been a
significant focus on two distinct categories: task-oriented (TOD) and
open-domain (chit-chat) dialogues. TOD systems aim to satisfy specific user
goals, such as finding a movie to watch, whereas open-domain systems primarily
focus on generating engaging conversations. A recent study by Chiu et al.
(2022) introduced SalesBot, which provides simulators and a dataset with
one-turn transition from chit-chat to task-oriented dialogues. However, the
previously generated data solely relied on BlenderBot, which raised concerns
about its long-turn naturalness and consistency during a conversation. To
address this issue, this paper aims to build SalesBot 2.0, a revised version of
the published data, by leveraging the commonsense knowledge of large language
models (LLMs) through proper prompting. The objective is to gradually bridge
the gap between chit-chat and TOD towards better naturalness and consistency.
The newly released large-scale dataset with detailed annotations exhibits
smoother transitions between topics and is more human-like in terms of
naturalness and consistency. It can serve as a valuable resource for both
academic research and commercial applications. Furthermore, our proposed
framework can be applied to generate numerous dialogues with various target
intents.
Chinese: 在最近的对话系统和语料库研究中，有两个截然不同的类别受到了显著关注：面向任务的（TOD）和开放域（闲聊）对话。TOD系统旨在满足特定的用户目标，例如找到一部电影来观看，而开放域系统主要关注于生成引人入胜的对话。Chiu等人（2022）的一项最新研究介绍了SalesBot，它提供了从闲聊到面向任务对话的单轮转换的模拟器和数据集。然而，之前生成数据完全依赖于BlenderBot，这引发了对其在对话过程中的长轮次自然性和一致性的担忧。为了解决这个问题，本文旨在通过适当的提示利用大型语言模型（LLMs）的常识知识，构建SalesBot 2.0，即已发布数据的修订版本。目标是逐步缩小闲聊和TOD之间的差距，以实现更好的自然性和一致性。新发布的大规模数据集具有详细的注释，展示了更平滑的主题转换，并且在自然性和一致性方面更加人性化。它可以为学术研究和商业应用提供宝贵的资源。此外，我们提出的框架可以应用于生成具有各种目标意图的众多对话。
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English: This is the second part of joint research in which we show that every
$2$-connected graph $G$ has the ${\cal F}_4$ property. That is, given distinct
$x_i\in V(G)$, $1\leq i\leq 4$, there is an $x_1x_2$-hamiltonian path in $G^2$
containing different edges $x_3y_3, x_4y_4\in E(G)$ for some $y_3,y_4\in V(G)$.
However, it was shown already in \cite[Theorem 2]{cf1:refer} that 2-connected
DT-graphs have the ${\cal F}_4$ property; based on this result we generalize it
to arbitrary $2$-connected graphs. We also show that these results are best
possible.
Chinese: 这是联合研究的第二部分，其中我们表明每个$2$-连通图$G$都具有${\cal F}_4$性质。也就是说，给定不同的$x_i\in V(G)$，$1\leq i\leq 4$，在$G^2$中存在一条$x_1x_2$-汉密尔顿路径，该路径包含不同的边$x_3y_3, x_4y_4\in E(G)$，其中$y_3,y_4\in V(G)$。然而，正如在\cite[定理2]{cf1:refer}中已经证明的那样，2-连通的DT图具有${\cal F}_4$性质；基于这个结果，我们将它推广到任意的$2$-连通图。我们还表明这些结果是最佳的。
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English: We consider the solution of the torsion problem $-\Delta u=1$ in $\Omega$ and
$u=0$ on $\partial \Omega$. Serrin's celebrated symmetry theorem states that,
if the normal derivative $u_\nu$ is constant on $\partial \Omega$, then
$\Omega$ must be a ball. In a recent paper, it has been conjectured that
Serrin's theorem may be obtained {\it by stability} in the following way:
first, for the solution $u$ of the torsion problem prove the estimate $$
r_e-r_i\leq C_t\,\Bigl(\max_{\Gamma_t} u-\min_{\Gamma_t} u\Bigr) $$ for some
constant $C_t$ depending on $t$, where $r_e$ and $r_i$ are the radii of an
annulus containing $\partial\Omega$ and $\Gamma_t$ is a surface parallel to
$\partial\Omega$ at distance $t$ and sufficiently close to $\partial\Omega$;
secondly, if in addition $u_\nu$ is constant on $\partial\Omega$, show that $$
\max_{\Gamma_t} u-\min_{\Gamma_t} u=o(C_t)\ \mbox{as} \ t\to 0^+. $$ In this
paper, we analyse a simple case study and show that the scheme is successful if
the admissible domains $\Omega$ are ellipses.
Chinese: 我们考虑在区域 $\Omega$ 中求解扭转问题 $-\Delta u=1$ 以及在 $\partial \Omega$ 上 $u=0$。Serrin 的著名对称定理指出，如果法向导数 $u_\nu$ 在 $\partial \Omega$ 上是常数，那么 $\Omega$ 必须是一个球体。在最近的一篇论文中，有人猜想Serrin定理可以通过以下方式通过稳定性获得：首先，对于扭转问题的解 $u$，证明对于某个依赖于 $t$ 的常数 $C_t$，有估计 $$
r_e-r_i\leq C_t\,\Bigl(\max_{\Gamma_t} u-\min_{\Gamma_t} u\Bigr) $$，其中 $r_e$ 和 $r_i$ 是包含 $\partial\Omega$ 的环形的半径，$\Gamma_t$ 是与 $\partial\Omega$ 平行且距离 $t$，并且足够接近 $\partial\Omega$ 的一个曲面；其次，如果此外 $u_\nu$ 在 $\partial\Omega$ 上也是常数，则证明 $$
\max_{\Gamma_t} u-\min_{\Gamma_t} u=o(C_t)\ \mbox{当} \ t\to 0^+ \ \mbox{时}。在这篇论文中，我们分析了一个简单的案例研究，并表明如果容许的区域 $\Omega$ 是椭圆，则该方案是成功的。
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English: We obtain a decay estimate for solutions to the linear dispersive equation
$iu_t-(-\Delta)^{1/4}u=0$ for $(t,x)\in\mathbb{R}\times\mathbb{R}$. This
corresponds to a factorization of the linearized water wave equation
$u_{tt}+(-\Delta)^{1/2}u=0$. In particular, by making use of the
Littlewood-Paley decomposition and stationary phase estimates, we obtain decay
of order $|t|^{-1/2}$ for solutions corresponding to data $u(0)=\varphi$,
assuming only bounds on $\lVert \varphi\rVert_{H_x^1(\mathbb{R})}$ and $\lVert
x\partial_x\varphi\rVert_{L_x^2(\mathbb{R})}$. As another application of these
ideas, we give an extension to equations of the form
$iu_t-(-\Delta)^{\alpha/2}u=0$ for a wider range of $\alpha$.
Chinese: 我们得到了线性弥散方程
$iu_t-(-\Delta)^{1/4}u=0$ 对于 $(t,x)\in\mathbb{R}\times\mathbb{R}$ 的衰减估计。这对应于线性化水波方程
$u_{tt}+(-\Delta)^{1/2}u=0$ 的分解。特别是，通过利用Littlewood-Paley分解和驻相估计，我们得到了对应于数据 $u(0)=\varphi$ 的解的衰减阶为 $|t|^{-1/2}$，假设只对 $\lVert \varphi\rVert_{H_x^1(\mathbb{R})}$ 和 $\lVert x\partial_x\varphi\rVert_{L_x^2(\mathbb{R})}$ 有界。作为这些想法的另一个应用，我们给出了对形式为
$iu_t-(-\Delta)^{\alpha/2}u=0$ 的方程的扩展，适用于更广泛的 $\alpha$ 范围。
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English: Electrical control of individual spins and photons in solids is key for
quantum technologies, but scaling down to small, static systems remains
challenging. Here, we demonstrate nanoscale electrical tuning of neutral and
charged excitons in monolayer WSe2 using 1-nm carbon nanotube gates.
Electrostatic simulations reveal a confinement radius below 15 nm, reaching the
exciton Bohr radius limit for few-layer dielectric spacing. In situ
photoluminescence spectroscopy shows gate-controlled conversion between neutral
excitons, negatively charged trions, and biexcitons at 4 K. Important for
quantum information processing applications, our measurements indicate gating
of a local 2D electron gas in the WSe2 layer, coupled to photons via trion
transitions with binding energies exceeding 20 meV. The ability to
deterministically tune and address quantum emitters using nanoscale gates
provides a pathway towards large-scale quantum optoelectronic circuits and
spin-photon interfaces for quantum networking.
Chinese: 固体中单个自旋和光子的电控对于量子技术至关重要，但缩小到小型静态系统仍然具有挑战性。在此，我们利用1纳米碳纳米管栅极实现了单层WSe2中中性激子和带电激子的纳米尺度电调谐。静电模拟揭示约束半径小于15纳米，达到多层介电间距的激子玻尔半径极限。原位光致发光光谱显示，在4 K温度下，通过栅极实现了中性激子、带负电的激子和双激子之间的栅控转换。对于量子信息处理应用而言，我们的测量表明WSe2层中局部二维电子气的栅控，通过结合能超过20 meV的激子跃迁与光子耦合。能够使用纳米尺度栅极确定性地调控和寻址量子发射器，为构建大规模量子光电电路和量子网络中的自旋-光子接口提供了途径。
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English: Arctic coastal morphology is governed by multiple factors, many of which are
affected by climatological changes. As the season length for shorefast ice
decreases and temperatures warm permafrost soils, coastlines are more
susceptible to erosion from storm waves. Such coastal erosion is a concern,
since the majority of the population centers and infrastructure in the Arctic
are located near the coasts. Stakeholders and decision makers increasingly need
models capable of scenario-based predictions to assess and mitigate the effects
of coastal morphology on infrastructure and land use. Our research uses
Gaussian process models to forecast Arctic coastal erosion along the Beaufort
Sea near Drew Point, AK. Gaussian process regression is a data-driven modeling
methodology capable of extracting patterns and trends from data-sparse
environments such as remote Arctic coastlines. To train our model, we use
annual coastline positions and near-shore summer temperature averages from
existing datasets and extend these data by extracting additional coastlines
from satellite imagery. We combine our calibrated models with future climate
models to generate a range of plausible future erosion scenarios. Our results
show that the Gaussian process methodology substantially improves yearly
predictions compared to linear and nonlinear least squares methods, and is
capable of generating detailed forecasts suitable for use by decision makers.
Chinese: 北极海岸的地貌受到多种因素的影响，其中许多因素受气候变化的影响。随着岸冰季节长度的缩短和永久冻土土壤温度的升高，海岸线更容易受到风暴波侵蚀。这种海岸侵蚀是一个值得关注的问题，因为北极大部分的人口中心和基础设施都位于海岸附近。利益相关者和决策者越来越需要能够进行基于情景预测的模型，以评估和减轻海岸地貌对基础设施和土地利用的影响。我们的研究使用高斯过程模型来预测阿拉斯加德鲁角附近波弗特海的海岸侵蚀。高斯过程回归是一种数据驱动建模方法，能够从数据稀疏的环境，如遥远的北极海岸线中提取模式和趋势。为了训练我们的模型，我们使用现有数据集中的年度海岸线位置和近岸夏季温度平均值，并通过从卫星图像中提取额外的海岸线来扩展这些数据。我们将我们的校准模型与未来气候模型相结合，生成一系列可能的未来侵蚀情景。我们的结果表明，与线性和非线性最小二乘法相比，高斯过程方法显著提高了年度预测的准确性，并且能够生成适合决策者使用的详细预测。
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English: The self-consistent tilted axis cranking covariant density functional theory
based on the point- coupling interaction PC-PK1 is applied to investigate the
possible existence of antimagnetic ro- tation in the nucleus Fe-58. The
observed data for Band 3 and Band 4 are reproduced well with two assigned
configurations. It is found that both bands correspond to a rotation of
antimagnetic character, but, due to the presence of considerable deformation,
the interplay between antimag- netic rotation and collective motion plays an
essential role. In particular for Band 4, collective rotation is dominant in
the competition with antimagnetic rotation. Moreover, it is shown that the
behavior of the ratios between the dynamic moments of inertia and the B(E2)
values reflects the interplay between antimagnetic and collective rotation.
Chinese: 基于点耦合相互作用PC-PK1的自洽倾斜轴转动协变密度泛函理论被应用于研究铁-58核中反磁性的旋转存在的可能性。第3和第4带的数据被两个指定的配置很好地重现。人们发现这两个带都对应于反磁性的旋转，但由于存在显著的形变，反磁性旋转与集体运动的相互作用起着至关重要的作用。特别是对于第4带，集体旋转在反磁性旋转的竞争中占主导地位。此外，动态惯性矩与B(E2)值比值的性质反映了反磁性和集体旋转之间的相互作用。
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English: Resistive pulse sensing has been widely used to characterize and count single
particles in solution moving through channels under an electric bias, with
nanoscale pores more recently providing enough spatial resolution for nucleic
acid sequencing at the single-molecule level. At its core, this technique
relies on measuring the drop in ionic current through the pore induced by the
passage of a molecule and, through conductance models, translating the blockage
signal to molecular dimensions. However, there exists no model considering the
resistive contributions of the pore exterior, i.e. the access regions, when
obstructed by a molecule. This is becoming increasingly important for low
aspect ratio pores, with the advent of 2D materials and ultrathin membranes. In
this work, a general method by which to model the resistance of the access
regions of a pore in the presence of an insulating obstruction is presented.
Thin oblate spheroidal slices are used to partition access regions and infer
their conductance when blocked by differently shaped objects. We show that our
model accurately estimates the blocked-state conductance of 2D and
finite-length pores as a function of the distance from the pore in the presence
of simple obstructions geometries (e.g. cylindrical and spherical objects) or
complex structures (i.e. sequence of simple obstruction sub-units). The model
is further shown to capture off-axis effects by predicting deeper blockages for
obstructions offset from the pore's central axis. A web-based tool is created
to predict the electrical signatures of a wide range of molecule geometries
translocating through differently shaped pores. The introduced model will help
guide experimental designs and thus presents a straightforward way to extend
the quantification of the resistive pulse technique at the nanoscale.
Chinese: 电阻脉冲传感已被广泛用于表征和计数在电偏压下通过通道移动的溶液中的单个粒子，近年来，纳米级孔提供了足够的空间分辨率，可以用于单分子水平的核酸测序。这种技术的核心在于测量分子通过孔时引起的离子电流的下降，并通过传导模型将阻塞信号转换为分子尺寸。然而，目前尚无模型考虑当分子阻塞时孔外部的电阻贡献，即入口区域。这对于低长宽比孔来说越来越重要，随着二维材料和超薄膜的出现。在这项工作中，提出了一种建模方法，用于模拟存在绝缘阻塞时孔的入口区域的电阻。使用薄扁球形切片来分区入口区域，并推断当被不同形状的物体阻塞时的导电性。我们表明，我们的模型可以准确地估计简单阻塞几何形状（例如圆柱形和球形物体）或复杂结构（即简单阻塞子单元的序列）下二维和有限长度孔的阻塞状态导电性，作为孔距离的函数。该模型还通过预测偏离孔中心轴的阻塞物体的更深阻塞来捕捉偏轴效应。创建了一个基于网络的工具，用于预测各种分子几何形状通过不同形状的孔的电信号。引入的模型将有助于指导实验设计，从而为扩展纳米尺度电阻脉冲技术的量化提供了一种简单直接的方法。
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English: A canonical band theory of non-collinear magnetism is developed and applied
to the close packed fcc and bcc crystal structures. Several examples of
non-collinear magnetism in the periodic table are seen to be canonical in
origin. This is a parameter free theory where the crystal and magnetic
symmetry, and exchange splitting, uniquely determine the electronic bands. The
only contribution to the determination of magnetic stability is the change in
band energy due to hybridisation resulting from spin mixing, and on this basis
we are able to analyse the origin of the stability of non-collinear magnetic
structures, and the instability of the FM state towards non-collinear ordering.
Chinese: 一种非共线磁性的典型带理论被开发并应用于密堆积的面心立方和体心立方晶体结构。在周期表中观察到几个非共线磁性的例子起源于典型。这是一个无参数的理论，其中晶体和磁性对称性以及交换分裂唯一确定电子能带。对磁稳定性确定的唯一贡献是由于自旋混合导致的杂化而产生的能带能量变化。基于这一点，我们能够分析非共线磁性结构稳定性的起源，以及顺磁性状态向非共线有序转变的不稳定性。
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English: Mixtures of Gaussian (or normal) distributions arise in a variety of
application areas. Many heuristics have been proposed for the task of finding
the component Gaussians given samples from the mixture, such as the EM
algorithm, a local-search heuristic from Dempster, Laird and Rubin [J. Roy.
Statist. Soc. Ser. B 39 (1977) 1-38]. These do not provably run in polynomial
time. We present the first algorithm that provably learns the component
Gaussians in time that is polynomial in the dimension. The Gaussians may have
arbitrary shape, but they must satisfy a ``separation condition'' which places
a lower bound on the distance between the centers of any two component
Gaussians. The mathematical results at the heart of our proof are ``distance
concentration'' results--proved using isoperimetric inequalities--which
establish bounds on the probability distribution of the distance between a pair
of points generated according to the mixture. We also formalize the more
general problem of max-likelihood fit of a Gaussian mixture to unstructured
data.
Chinese: 高斯（或正态）分布的混合物在各种应用领域中都会出现。为了根据混合物样本找到其组分高斯分布，已经提出了许多启发式算法，例如来自Dempster、Laird和Rubin的EM算法（[J. Roy. Statist. Soc. Ser. B 39 (1977) 1-38]），这是一种局部搜索启发式算法。但这些算法在多项式时间内运行并未得到证明。我们提出了第一个在维度多项式时间内可证明学习组分高斯分布的算法。这些高斯分布可以具有任意形状，但它们必须满足一个“分离条件”，该条件对任意两个组分高斯分布的中心之间的距离设置了下限。我们证明的核心数学结果是“距离集中”结果——这些结果通过等周不等式得到证明，它们为根据混合物生成的点对之间的距离的概率分布建立了界限。我们还形式化了更一般的问题：将高斯混合物拟合到非结构化数据的最大似然拟合问题。
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English: The multiverse view in set theory, introduced and argued for in this article,
is the view that there are many distinct concepts of set, each instantiated in
a corresponding set-theoretic universe. The universe view, in contrast, asserts
that there is an absolute background set concept, with a corresponding absolute
set-theoretic universe in which every set-theoretic question has a definite
answer. The multiverse position, I argue, explains our experience with the
enormous diversity of set-theoretic possibilities, a phenomenon that challenges
the universe view. In particular, I argue that the continuum hypothesis is
settled on the multiverse view by our extensive knowledge about how it behaves
in the multiverse, and as a result it can no longer be settled in the manner
formerly hoped for.
Chinese: 集合论中的多重宇宙观点，在本文中被引入和论证，该观点认为存在许多不同的集合概念，每个概念都在相应的集合论宇宙中得到体现。相比之下，宇宙观点断言存在一个绝对背景集合概念，以及相应的绝对集合论宇宙，在其中每个集合论问题都有一个确定的答案。我认为，多重宇宙立场解释了我们关于集合论可能性巨大多样性的经验，这一现象挑战了宇宙观点。特别是，我认为连续统假设在多重宇宙观点上已经得到解决，这是基于我们广泛了解它在多重宇宙中的行为方式，因此它不再能以以前希望的方式得到解决。
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English: Hyperbolic flows, as formulated by Anosov, are the prototypes of chaotic
evolutions in classical dynamical systems. Here we provide a concise updated
account of their quantum counterparts originally formulated by Emch, Narnhofer,
Thirring and Sewell within the operator algebraic setting of quantum theory:
and we discuss their bearing on the question of quantum chaos.
Chinese: 由Anosov提出的超行流是经典动力系统中混沌演化的原型。在这里，我们提供了在量子理论的算子代数框架内，由Emch、Narnhofer、Thirring和Sewell最初提出的其量子对应物的简要更新说明：并讨论了它们对量子混沌问题的关联。
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English: Archival Vilnius CCD photometric observations are presented for the heavily
reddened star cluster Melotte 105, resulting in colour-magnitude diagrams and
spectral class estimates. There is considerable lack of agreement between
studies for reddening, age, and distance for this cluster explaining why the
archival data are being made available by this paper. The derived reddening
E(B-V =0.34 +/- 0.04 mag and the distance V-M =12.9 +/- 0.3 mag directly from
the Vilnius photometry. The Gaia Data Release 2 (DR2) and Vilnius photometric
data of the cluster were used to estimate the structural parameters of the
cluster, probability of stellar membership in the cluster, the distance modulus
and the cluster age. Lack of $Y$ band observations prevented determination of
metal abundance. The values of the colour excess and distance module are
determined by two different methods (i.e., Q and Zero Age Main Sequence, or
ZAMS, methods). A distance modulus of 12.85 +/- 0.07 mag was derived by ZAMS
fitting, in good agreement with the above estimate. ZAMS fitting indicates a
reddening of 0.403 +/- 0.02 mag, within two sigma of the estimate above. The
cluster's metallicity and age are estimated to be 0.24 dex and 240 +/-25 Myr,
respectively. The derived mass function is in good agreement with the Salpeter
slope. The cluster space velocity components (U, V, W) were determined as
(-3.90 +/- 3.34, -13.76 +/- 5.69, +3.45 +/- 0.41) km/s. Perigalactic and
apogalactic distances were obtained as R_{p} = 6.85 and R_{a} = 7.44 kpc
respectively. The maximum vertical distance from the Galactic plane was
calculated as Z_{max} = 84 pc and the eccentricity of the orbit was determined
as e = 0.042.
Chinese: 本文展示了维尔纽斯天文台对严重红化的星团梅洛特105的测光观测数据，得到了颜色-亮度图和光谱类型估计。关于该星团的红化、年龄和距离的研究之间缺乏一致性，这也是为什么本文提供存档数据的原因。通过维尔纽斯测光直接得到的光度红化E(B-V) = 0.34 +/- 0.04等磁和距离V-M = 12.9 +/- 0.3等磁。利用盖亚数据发布2版（DR2）和维尔纽斯测光数据估计了星团的结构参数、星团内恒星成员的概率、距离指数和星团年龄。由于缺乏Y波段观测，无法确定金属丰度。颜色超量和距离指数的值通过两种不同的方法（即Q方法和零年龄主序星，或ZAMS方法）确定。通过ZAMS拟合得到距离指数为12.85 +/- 0.07等磁，与上述估计值良好一致。ZAMS拟合表明红化值为0.403 +/- 0.02等磁，与上述估计值在两个标准差范围内。星团的金属丰度和年龄估计分别为0.24等磁和240 +/-25百万年。得到的质量函数与Salpeter斜率良好一致。星团的空间速度分量（U，V，W）确定为(-3.90 +/- 3.34，-13.76 +/- 5.69，+3.45 +/- 0.41) km/s。得到近银心和远银心的距离分别为R_{p} = 6.85和R_{a} = 7.44 kpc。计算得到从银盘的最大垂直距离为Z_{max} = 84 pc，轨道偏心率为e = 0.042。
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English: The spin-spin correlation function of the 2D XY model decays as a power law
at all temperatures below the Berezinskii-Kosterlitz-Thouless transition point
with a temperature dependent exponent $\eta=\eta(T/J)$ ($J$ is the
ferromagnetic coupling strength). It is known from computer experiments that in
the 2D XY model with site or bond dilution this exponent depends on
concentration $p$ of removed sites/bonds as well. Knowing the slope
$\partial\eta/\partial p$ at point $p=0$, one can predict the value of the
exponent for small dilution concentrations:
$\eta(p)\simeq\eta(0)+p(\partial\eta/\partial p)|_{p=0}$. As it is shown in
this paper, the spin-wave Hamiltonian allows to obtain exact results for this
slope: $(\partial\eta/\partial p)|_{p=0} = T/(2J) + O((T/J)^2)$ and $T/(\pi J)
+ O((T/J)^2)$ for site and for bond dilution, respectively.
Chinese: 二维XY模型的自旋-自旋相关函数在低于Berezinskii-Kosterlitz-Thouless相变点的所有温度下都按照幂律衰减，其指数与温度相关，表示为 $\eta=\eta(T/J)$（其中$J$是铁磁耦合强度）。计算机实验表明，在二维XY模型中，对于点或键稀释，这个指数还依赖于去除的点/键的浓度$p$。已知在点$p=0$处的斜率$\partial\eta/\partial p$，可以预测小稀释浓度下指数的值：$\eta(p)\simeq\eta(0)+p(\partial\eta/\partial p)|_{p=0}$。正如本文所示，自旋波哈密顿量允许获得此斜率的精确结果：$(\partial\eta/\partial p)|_{p=0} = T/(2J) + O((T/J)^2)$ 和 $T/(\pi J) + O((T/J)^2)$，分别对应于点和键稀释。
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English: The Sachdev-Ye-Kitaev (SYK) model describes interacting fermionic zero modes
in zero spatial dimensions, e.g. quantum dot, with interactions strong enough
to completely washout quasiparticle excitations in the infrared. In this paper,
we consider the complex-valued SYK model at initial temperature $T$ and
chemical potential $\mu$ coupled to a large reservoir by a quench at time
$t=0$. The reservoir is kept at zero temperature and charge neutrality. We find
that the dynamics of the discharging process of the SYK quantum dot reveals a
distinctive characteristic of the SYK non-Fermi liquid (nFl) state. In
particular, we focus on the tunneling current induced by the quench. We show
that the temperature dependent contribution to the current's half-life scales
linearly in $T$ at low temperatures for the SYK nFl state, while for the Fermi
liquid it scales as $T^2$.
Chinese: 萨克斯-叶-基塔耶夫(SYK)模型描述了零空间维度内，例如量子点中，相互作用的费米零模。这些相互作用足够强，以至于在红外区域完全洗掉准粒子激发。在本论文中，我们考虑一个复数值的SYK模型，初始温度为$T$，化学势为$\mu$，并在$t=0$时通过一个猝变与一个大型储层耦合。储层保持零温度和中性电荷。我们发现，SYK量子点的放电过程的动态揭示了SYK非费米液体(nFl)态的一个独特特征。特别是，我们专注于由猝变引起的隧穿电流。我们表明，对于SYK nFl态，电流半衰期对温度的依赖性在低温下线性地与$T$成比例，而对于费米液体，它则按$T^2$的比例缩放。
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English: The quenched scalar Yukawa theory is solved in the light-front Tamm-Dancoff
approach including up to four constituents (one scalar nucleon, three scalar
pions). The Fock sector dependent renormalization is implemented. By studying
the Fock sector norms, we find that the lowest two Fock sectors dominate the
state even in the large-coupling region. The one-body sector shows convergence
with respect to the Fock sector truncation. However, the four-body norm exceeds
the three-body norm at the coupling $\alpha \approx 1.7$.
Chinese: 在包含最多四个成分（一个标量核子，三个标量π介子）的光前Tamm-Dancoff方法中求解了淬灭标量Yukawa理论。实现了费克子空间依赖的正规化。通过研究费克子空间的规范，我们发现在耦合强度较大的区域内，最低的两个费克子空间仍然主导着状态。一粒子子空间对于费克子空间截断表现出收敛。然而，在耦合强度 α ≈ 1.7 时，四粒子规范超过了三粒子规范。
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English: In this paper, robust control with sea state observer and dynamic thrust
allocation is proposed for the Dynamic Positioning (DP) of an accommodation
vessel in the presence of unknown hydrodynamic force variation and the input
time delay. In order to overcome the huge force variation due to the adjoining
Floating Production Storage and Offloading (FPSO) and accommodation vessel, a
novel sea state observer is designed. The sea observer can effectively monitor
the variation of the drift wave-induced force on the vessel and activate Neural
Network (NN) compensator in the controller when large wave force is identified.
Moreover, the wind drag coefficients can be adaptively approximated in the sea
observer so that a feedforward control can be achieved. Based on this, a robust
constrained control is developed to guarantee a safe operation. The time delay
inside the control input is also considered. Dynamic thrust allocation module
is presented to distribute the generalized control input among azimuth
thrusters. Under the proposed sea observer and control, the boundedness of all
the closed-loop signals are demonstrated via rigorous Lyapunov analysis. A set
of simulation studies are conducted to verify the effectiveness of the proposed
control scheme.
Chinese: 在本文中，针对存在未知水动力力和输入时间延迟的情况，提出了一种具有海况观测器和动态推力分配的鲁棒控制方法，用于住宿船的动态定位（DP）。为了克服相邻的浮式生产、储存和卸载（FPSO）和住宿船引起的巨大力变化，设计了一种新型的海况观测器。海况观测器可以有效地监测船舶上由漂流波引起的力变化，并在识别出大浪力时激活控制器中的神经网络（NN）补偿器。此外，海况观测器可以自适应地近似风阻系数，从而实现前馈控制。基于此，开发了一种鲁棒约束控制，以确保安全运行。同时，也考虑了控制输入内的时延。提出了一个动态推力分配模块，用于将广义控制输入分配到方位推进器中。在所提出的海况观测器和控制下，通过严格的李雅普诺夫分析证明了所有闭环信号的有界性。进行了一系列仿真研究，以验证所提出的控制方案的有效性。
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English: Panoramic videos contain richer spatial information and have attracted
tremendous amounts of attention due to their exceptional experience in some
fields such as autonomous driving and virtual reality. However, existing
datasets for video segmentation only focus on conventional planar images. To
address the challenge, in this paper, we present a panoramic video dataset,
PanoVOS. The dataset provides 150 videos with high video resolutions and
diverse motions. To quantify the domain gap between 2D planar videos and
panoramic videos, we evaluate 15 off-the-shelf video object segmentation (VOS)
models on PanoVOS. Through error analysis, we found that all of them fail to
tackle pixel-level content discontinues of panoramic videos. Thus, we present a
Panoramic Space Consistency Transformer (PSCFormer), which can effectively
utilize the semantic boundary information of the previous frame for pixel-level
matching with the current frame. Extensive experiments demonstrate that
compared with the previous SOTA models, our PSCFormer network exhibits a great
advantage in terms of segmentation results under the panoramic setting. Our
dataset poses new challenges in panoramic VOS and we hope that our PanoVOS can
advance the development of panoramic segmentation/tracking.
Chinese: 全景视频包含更丰富的空间信息，并在自动驾驶、虚拟现实等领域因其卓越的体验效果而备受关注。然而，现有的视频分割数据集仅关注传统的平面图像。为应对这一挑战，在本文中，我们提出了一个全景视频数据集PanoVOS。该数据集提供150个高视频分辨率且运动多样的视频。为量化二维平面视频与全景视频之间的领域差距，我们在PanoVOS上评估了15个现成的视频对象分割（VOS）模型。通过误差分析，我们发现它们均无法处理全景视频的像素级内容不连续性。因此，我们提出了全景空间一致性Transformer（PSCFormer），该模型能有效利用前一帧的语义边界信息，与当前帧进行像素级匹配。大量实验表明，与之前的SOTA模型相比，我们的PSCFormer网络在全景设置下的分割结果具有显著优势。我们的数据集为全景VOS提出了新的挑战，我们希望PanoVOS能推动全景分割/跟踪技术的发展。
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English: We present the new spectrometer for the neutron electric dipole moment (nEDM)
search at the Paul Scherrer Institute (PSI), called n2EDM. The setup is at room
temperature in vacuum using ultracold neutrons. n2EDM features a large UCN
double storage chamber design with neutron transport adapted to the PSI UCN
source. The design builds on experience gained from the previous apparatus
operated at PSI until 2017. An order of magnitude increase in sensitivity is
calculated for the new baseline setup based on scalable results from the
previous apparatus, and the UCN source performance achieved in 2016.
Chinese: 我们介绍了在保罗·谢尔研究所（PSI）用于中子电偶极矩（nEDM）搜索的新光谱仪，称为n2EDM。该装置在室温真空下使用超冷中子。n2EDM具有大型UCN双存储室设计，其中中子传输适应PSI UCN源。设计基于从2017年前在PSI运行的先前装置中获得的经验。根据先前装置的可扩展结果和在2016年实现的UCN源性能，预计新基准设置将提高一个数量级的灵敏度。
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English: The dualities that map hard-to-solve, interacting theories to free,
non-interacting ones often trigger a deeper understanding of the systems to
which they apply. However, simplifying assumptions such as Lorentz invariance,
low dimensionality, or the absence of axial gauge fields, limit their
application to a broad class of systems, including topological semimetals. Here
we derive several axial field theory dualities in 2+1 and 3+1 dimensions by
developing an axial slave-rotor approach capable of accounting for the axial
anomaly. Our 2+1-dimensional duality suggests the existence of a dual, critical
surface theory for strained three-dimensional non-symmorphic topological
insulators. Our 3+1-dimensional duality maps free Dirac fermions to Dirac
fermions coupled to emergent U(1) and Kalb-Ramond vector and axial gauge
fields. Upon fixing an axial field configuration that breaks Lorentz
invariance, this duality maps free to interacting Weyl semimetals, thereby
suggesting that the quantization of the non-linear circular photogalvanic
effect can be robust to certain interactions. Our work emphasizes how axial and
Lorentz-breaking dualities improve our understanding of topological matter.
Chinese: 将难以求解、相互作用的理论映射到自由、非相互作用理论的双性，往往能引发对它们所适用系统的更深刻理解。然而，诸如洛伦兹不变性、低维度或缺乏轴规范场的简化假设，限制了它们在包括拓扑半金属在内的大量系统中的应用。在此，我们通过发展一种能够考虑轴异常的轴规范场奴役转子方法，推导出2+1维和3+1维的几个轴规范场理论双性。我们的2+1维双性表明，对于受应变的三维非对称晶格拓扑绝缘体，存在一种双性的临界表面理论。我们的3+1维双性将自由狄拉克费米子映射到与涌现的U(1)规范场和Kalb-Ramond矢量及轴规范场耦合的狄拉克费米子。通过固定一个破坏洛伦兹不变性的轴规范场配置，该双性将自由映射到相互作用的Weyl半金属，从而表明非线性圆光电效应的量化对某些相互作用具有鲁棒性。我们的工作强调了轴双性和洛伦兹破缺双性如何增进我们对拓扑物质的理解。
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English: The study of entanglement in multipartite quantum states plays a major role
in quantum information theory and genuine multipartite entanglement signals one
of its strongest forms for applications. However, its characterization for
general (mixed) states is a highly nontrivial problem. We introduce a
particularly simple subclass of multipartite states, which we term
pair-entangled network (PEN) states, as those that can be created by
distributing exclusively bipartite entanglement in a connected network. We show
that genuine multipartite entanglement in a PEN state depends on both the level
of noise and the network topology and, in sharp contrast to the case of pure
states, it is not guaranteed by the mere distribution of mixed bipartite
entangled states. Our main result is a markedly drastic feature of this
phenomenon: the amount of connectivity in the network determines whether
genuine multipartite entanglement is robust to noise for any system size or
whether it is completely washed out under the slightest form of noise for a
sufficiently large number of parties. This latter case implies fundamental
limitations for the application of certain networks in realistic scenarios,
where the presence of some form of noise is unavoidable. To illustrate the
applicability of PEN states to study the complex phenomenology behind
multipartite entanglement, we also use them to prove superactivation of genuine
multipartite nonlocality for any number of parties.
Chinese: 纠缠在多体量子态中的研究在量子信息理论中扮演着重要角色，而真正的多体纠缠是其最强形式之一，适用于实际应用。然而，对于一般（混合）态的纠缠特征化是一个非常非平凡的问题。我们引入了一类特别简单的多体态子类，称之为配对纠缠网络（PEN）态，即那些可以通过在连接网络中独家分配双体纠缠而产生的态。我们证明，在PEN态中真正的多体纠缠不仅取决于噪声的水平，还取决于网络拓扑结构，与纯态的情况形成鲜明对比，仅仅分配混合双体纠缠态并不能保证真正的多体纠缠存在。我们的主要结果是这一现象的一个显著特征：网络中的连接程度决定了对于任何系统规模，真正的多体纠缠是否对噪声具有鲁棒性，还是在足够多的参与方下，即使是最轻微的噪声也会将其完全消除。后者在某些网络在现实场景中的应用中暗示了基本限制，因为在现实场景中不可避免地存在某种形式的噪声。为了说明PEN态在研究多体纠缠背后的复杂现象方面的适用性，我们还使用它们证明了对于任何数量的参与方，真正的多体非局域性存在超激活现象。
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English: Aims. We provide an in-depth analysis of the COSMOS-Web ring, an Einstein
ring at z=2 that we serendipitously discovered in the COSMOS-Web survey and
possibly the most distant lens discovered to date.
Methods. We extract the visible and NIR photometry from more than 25 bands
and we derive the photometric redshifts and physical properties of both the
lens and the source with three different SED fitting codes. Using JWST/NIRCam
images, we also produce two lens models to (i) recover the total mass of the
lens, (ii) derive the magnification of the system, (iii) reconstruct the
morphology of the lensed source, and (iv) measure the slope of the total mass
density profile of the lens.
Results. The lens is a very massive and quiescent (sSFR < 10^(-13) yr-1)
elliptical galaxy at z = 2.02 \pm 0.02 with a total mass Mtot(<thetaE) = (3.66
\pm 0.36) x 10^11 Msun and a stellar mass M* = (1.37 \pm 0.14) x 10^11 Msun.
Compared to SHMRs from the literature, we find that the total mass is
consistent with the presence of a DM halo of mass Mh = 1.09^(+1.46)_(-0.57) x
10^13 Msun. In addition, the background source is a M* = (1.26 \pm 0.17) x
10^10 Msun star-forming galaxy (SFR=(78 \pm 15) Msun/yr) at z = 5.48 \pm 0.06.
Its reconstructed morphology shows two components with different colors. Dust
attenuation values from SED fitting and nearby detections in the FIR also
suggest it could be partially dust-obscured.
Conclusions. We find the lens at z=2. Its total, stellar, and DM halo masses
are consistent within the Einstein ring, so we do not need any unexpected
changes in our description of the lens (e.g. change its IMF or include a
non-negligible gas contribution). The most likely solution for the lensed
source is at z = 5.5. Its reconstructed morphology is complex and highly
wavelength dependent, possibly because it is a merger or a main sequence galaxy
with a heterogeneous dust distribution.
Chinese: 目标。我们对COSMOS-Web环进行了深入分析，这是一个在z=2时通过COSMOS-Web巡天意外发现的艾因斯坦环，可能是迄今为止发现的最遥远的引力透镜。
方法。我们从超过25个波段中提取了可见光和近红外光度测量数据，并使用三种不同的SED拟合代码推导出透镜和源的光度红移和物理性质。利用JWST/NIRCam图像，我们还生成了两个透镜模型，以（i）恢复透镜的总质量，（ii）推导系统的放大倍率，（iii）重建透镜源的形态，以及（iv）测量透镜总质量密度分布的斜率。
结果。透镜是一个在z = 2.02 ± 0.02时非常致密且处于宁静状态（sSFR < 10^(-13) yr^-1）的椭圆星系，其总质量Mtot(<θE) = (3.66 ± 0.36) x 10^11太阳质量，恒星质量M* = (1.37 ± 0.14) x 10^11太阳质量。与文献中的SHMRs相比，我们发现总质量与存在一个质量为Mh = 1.09^(+1.46)_(-0.57) x 10^13太阳质量的暗物质晕是一致的。此外，背景源是一个M* = (1.26 ± 0.17) x 10^10太阳质量、形成恒星的星系（SFR=(78 ± 15)太阳质量/年），位于z = 5.48 ± 0.06。其重建的形态显示有两个不同颜色的成分。SED拟合的尘埃衰减值以及近红外探测到的附近发现也表明它可能部分被尘埃遮挡。
结论。我们发现了一个位于z=2的透镜。其总质量、恒星质量和暗物质晕质量在艾因斯坦环内是一致的，因此我们不需要对我们的透镜描述进行任何意外的改变（例如改变其IMF或包括一个不可忽略的气体贡献）。透镜源最可能的解决方案位于z = 5.5。其重建的形态复杂且高度依赖于波长，可能因为它是一个合并星系或一个具有异质尘埃分布的主序星系。
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English: Creeping flow of polymeric fluid without inertia exhibits elastic
instabilities and elastic turbulence accompanied by drag enhancement due to
elastic stress produced by flow-stretched polymers. However, in
inertia-dominated flow at high $\mbox{Re}$ and low fluid elasticity $El$, a
reduction in turbulent frictional drag is caused by an intricate competition
between inertial and elastic stresses. Here, we explore the effect of inertia
on the stability of viscoelastic flow in a broad range of control parameters
$El$ and $(\mbox{Re}, \mbox{Wi})$. We present the stability diagram of observed
flow regimes in $\mbox{Wi}-\mbox{Re}$ coordinates and find that instabilities'
onsets show unexpectedly non-monotonic dependence on $El$. Further, three
distinct regions in the diagram are identified based on $El$. Strikingly, for
high elasticity fluids we discover a complete relaminarization of flow at
Reynolds number of the order of unity, different from a well-known turbulent
drag reduction. These counterintuitive effects may be explained by a finite
polymer extensibility and a suppression of vorticity at high $\mbox{Wi}$. Our
results call for further theoretical and numerical development to uncover the
role of inertial effect on elastic turbulence in a viscoelastic flow.
Chinese: 聚合物流体的无惯性层流表现出弹性不稳定性以及伴随弹性应力产生的阻力增强的弹性湍流。然而，在惯性主导的高Reynolds数和低流体弹性El的流动中，由于惯性应力和弹性应力之间的复杂竞争，湍流摩擦阻力减少。在这里，我们探讨了惯性对广泛控制参数El和(Re, Wi)下粘弹性流动稳定性的影响。我们展示了Wi-Re坐标系中观察到的流动状态的稳定性图，并发现不稳定性开始出现对El的依赖性出乎意料地非单调。此外，根据El在图中确定了三个不同的区域。引人注目的是，对于高弹性流体，我们在Reynolds数为一的数量级上发现了流动的完全再层流化，这与已知的湍流阻力减少不同。这些反直觉的效果可能可以通过有限的聚合物可拉伸性和在高Wi下涡旋的抑制来解释。我们的结果呼吁进一步的理论和数值发展，以揭示惯性效应对粘弹性流动中弹性湍流的作用。
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English: The $r$-process-enhanced (RPE) stars provide fossil records of the assembly
history of the Milky Way and the nucleosynthesis of the heaviest elements.
Observations by the $R$-Process Alliance (RPA) and others have confirmed that
many RPE stars are associated with chemo-dynamically tagged groups, which
likely came from accreted dwarf galaxies of the Milky Way (MW). However, we do
not know how RPE stars are formed. Here, we present the result of a
cosmological zoom-in simulation of an MW-like galaxy with $r$-process
enrichment, performed with the highest resolution in both time and mass. Thanks
to this advancement, unlike previous simulations, we find that most highly RPE
($r$-II; [Eu/Fe] $> +0.7$) stars are formed in low-mass dwarf galaxies that
have been enriched in $r$-process elements for [Fe/H] $\,<-2.5$, while those
with higher metallicity are formed in situ, in locally enhanced gas clumps that
were not necessarily members of dwarf galaxies. This result suggests that
low-mass accreted dwarf galaxies are the main formation site of $r$-II stars
with [Fe/H] $\,<-2.5$. We also find that most low-metallicity $r$-II stars
exhibit halo-like kinematics. Some $r$-II stars formed in the same halo show
low dispersions in [Fe/H] and somewhat larger dispersions of [Eu/Fe], similar
to the observations. The fraction of simulated $r$-II stars is commensurate
with observations from the RPA, and the distribution of the predicted [Eu/Fe]
for halo $r$-II stars matches that observed. These results demonstrate that RPE
stars can be valuable probes of the accretion of dwarf galaxies in the early
stages of their formation.
Chinese: $r$-过程增强（RPE）星提供了银河系组装历史和最重元素核合成的化石记录。$R$-过程联盟（RPA）和其他观测已经确认，许多RPE星与化学动力学标记群有关，这些群很可能来自被银河系（MW）吞并的矮星系。然而，我们还不知道RPE星是如何形成的。在这里，我们呈现了一项对类似银河系的星系进行高分辨率宇宙模拟的结果，该星系具有$r$-过程增强。这项模拟在时间和质量上都达到了迄今为止最高的分辨率。得益于这一进步，与之前的模拟不同，我们发现大多数高度RPE的（$r$-II；[Eu/Fe] > +0.7）星是在金属丰度[Fe/H] < -2.5的低质量矮星系中形成的，这些矮星系已经富含$r$-过程元素，而那些金属丰度更高的星是在原位形成的，在局部增强的气体团块中，这些团块不一定是矮星系的一部分。这一结果表明，低质量被吞并的矮星系是[Fe/H] < -2.5的$r$-II星的主要形成场所。我们还发现，大多数低金属丰度的$r$-II星表现出晕星系的动力学特性。在同一个晕中形成的$r$-II星在[Fe/H]上表现出低分散性，在[Eu/Fe]上表现出稍大的分散性，与观测结果相似。模拟的$r$-II星的数量与RPA的观测结果相符，预测的晕中$r$-II星的[Eu/Fe]分布与观测结果一致。这些结果表明，RPE星可以成为研究早期银河系形成阶段矮星系吞并的有价值探针。
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English: Eta Carinae (or Eta Car) is a colliding-wind binary that shows non-thermal
emission from hard X-rays to high-energy $\gamma$-rays. The $\gamma$-ray
spectrum exhibits two spectral components, where the high-energy component
extends up to 300 GeV. Previous observations of Eta Carinae with the High
Energy Stereoscopic System (H.E.S.S.) resulted in upper limits. With the
addition of the large 28-m central telescope to the H.E.S.S. array in 2012 the
lower bound on the energy range has significantly been reduced. This lowers the
energy threshold of the analysis compared to the published results due to the
improved instrument sensitivity at energies below 400 GeV. Eta Carinae has been
regularly observed in the following years with H.E.S.S. II. Here we report on
the first results of Eta Carinae observations, which also cover the periastron
passage in 2014 - the time of maximum $\gamma$-ray emission seen in GeV
$\gamma$-rays with Fermi-LAT.
Chinese: 参宿七（或简称参宿七）是一对碰撞风双星，它从硬X射线到高能$\gamma$-射线表现出非热辐射。$\gamma$-射线谱显示出两个光谱成分，其中高能成分可延伸至300 GeV。之前使用高能立体系统（H.E.S.S.）对参宿七的观测得到了上限值。2012年，在H.E.S.S.阵列中增加了28米中央望远镜后，能量范围的下限显著降低。由于在低于400 GeV的能量下仪器灵敏度提高，分析的能量阈值与已发表的结果相比有所降低。在接下来的几年里，参宿七使用H.E.S.S. II进行了定期观测。这里我们报告了参宿七观测的第一个结果，这些结果也涵盖了2014年的近日点通过——这是在GeV $\gamma$-射线中由费米-LAT观测到的最大$\gamma$-射线发射时间。
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English: This paper studies a statistical network model generated by a large number of
randomly sized overlapping communities, where any pair of nodes sharing a
community is linked with probability $q$ via the community. In the special case
with $q=1$ the model reduces to a random intersection graph which is known to
generate high levels of transitivity also in the sparse context. The parameter
$q$ adds a degree of freedom and leads to a parsimonious and analytically
tractable network model with tunable density, transitivity, and degree
fluctuations. We prove that the parameters of this model can be consistently
estimated in the large and sparse limiting regime using moment estimators based
on partially observed densities of links, 2-stars, and triangles.
Chinese: 本文研究了一种由大量随机规模的相互重叠社区生成的统计网络模型，其中任何共享一个社区的节点对以概率 $q$ 通过社区相互连接。在 $q=1$ 的特殊情况下，该模型简化为随机交叠图，已知即使在稀疏环境中也能生成高水平的传递性。参数 $q$ 增加了一个自由度，导致一个节省且易于分析的具有可调密度、传递性和度波动性的网络模型。我们证明，使用基于部分观察到的链接、2-星和三角形密度的矩估计器，可以在大和稀疏极限状态下一致地估计该模型的参数。
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English: We present an analysis of the secular variability of the longitudinal
magnetic field B_e in the roAp star gamma Equ (HD 201601). Measurements of the
stellar magnetic field B_e were mostly compiled from the literature, and append
also our 33 new B_e measurements which were obtained with the 1-m optical
telescope of Special Astrophysical Observatory (Russia). All the available data
cover the time period of 58 years, and include both phases of the maximum and
minimum B_e. We determined that the period of the long-term magnetic B_e
variations equals 91.1 +/- 3.6 years, with B_e (max) = + 577 +/- 31 G and B_e
(min) = -1101 +/- 31 G.
Chinese: 我们提出对罗阿普星γ Equ（HD 201601）纵向磁场B_e的长期变化的分析。恒星磁场B_e的测量数据主要来自文献，并附上我们用俄罗斯特殊天体物理观测站的1米光学望远镜获得的33个新的B_e测量值。所有可用数据覆盖了58年的时间段，包括B_e最大值和最小值的两个阶段。我们确定长期磁场B_e变化的周期为91.1 +/- 3.6年，B_e（最大）= + 577 +/- 31高斯，B_e（最小）= -1101 +/- 31高斯。
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English: Root systems can influence the dynamics of evapotranspiration of water out of
a porous medium. The coupling of evapotranspiration remains a key aspect
affecting overall root behavior. Predicting the evapotranspiration curve in the
presence of roots helps keep track of the amount of water that remains in the
porous medium. Using a controlled visual set-up of a 2D model soil system
consisting of monodisperse glass beads, we first perform experiments on actual
roots grown in partially saturated systems under different relative humidity
conditions. We record parameters such as the total mass loss in the medium and
the resulting position of the receding fronts and use these experimental
results to develop a simple analytical model that predicts the position of the
evaporating front as a function of time as well as the total amount of water
that is lost from the medium due to the combined effects of evaporation and
transpiration. The model is based on fundamental principles of evaporation flux
and includes empirical assumptions on the quantity of stoma in the leaves and
the transition time between regime 1 and regime 2. The model also underscores
the importance of a much prolonged root life as long as the root is exposed to
a partially saturated zone composed of a mixture of air and water. Comparison
between the model and experimental results shows good prediction of the
position of the evaporating front as well as the total mass loss from
evapotranspiration in the presence of real root systems. These results provide
additional understanding of both complex evaporation phenomenon and its
influence on root mechanisms.
Chinese: 根系系统能够影响从多孔介质中蒸发散失水分的动力学过程。根系与蒸发散失的耦合是影响整体根系行为的关键方面。预测存在根系时的蒸发散失曲线有助于追踪多孔介质中剩余水分的数量。通过使用由单分散玻璃珠组成的受控视觉设置的二维模型土壤系统，我们首先在不同相对湿度条件下对实际生长在部分饱和系统中的根系进行实验。我们记录了介质总质量损失和后退前沿的最终位置等参数，并利用这些实验结果开发了一个简单的分析模型，该模型可以预测蒸发前沿随时间的位置，以及由于蒸发和蒸腾的复合效应导致的介质中水分的总损失量。该模型基于蒸发通量的基本原理，并包括了叶片气孔数量和第一阶段与第二阶段转换时间的实验假设。此外，该模型强调了只要根系暴露在由空气和水混合而成的部分饱和区域中，根系寿命的显著延长的重要性。模型与实验结果的比较显示，对于存在真实根系系统的情况，模型能够很好地预测蒸发前沿的位置以及由于蒸发和蒸腾复合效应导致的总质量损失。这些结果为复杂蒸发现象及其对根系机制的影响提供了额外的了解。
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English: Threshold tolerance graphs and their complement graphs, known as co-TT
graphs, were introduced by Monma, Reed, and Trotter[24]. Building on this, Hell
et al.[19] introduced the concept of negative interval. Then they proceeded to
define signedinterval digraphs/ bigraphs, demonstrating their equivalence to
several seemingly distinct classes of digraphs/ bigraphs. They also showed that
co-TT graphs are equivalent to symmetric signed-interval digraphs, where some
vertices of the digraphs have loops and others do not. We have showed that this
actually solve the representation characterization problem of co-TT graphs
posed by Monma, Reed and Trotter [24]. In this paper, we characterize
signed-interval bigraphs and signed-interval graphs in terms of their
biadjacency matrices and adjacency matrices, respectively. Moreover we
emphasize on the geometric representation of signed-interval graphs, i.e. co-TT
graphs. Finally, by utilizing the geometric representation of signed-interval
graphs, we resolve the open problem of characterizing co-TT graphs in terms of
minimal forbidden induced subgraphs, a problem initially posed by Monma, Reed,
and Trotter in the same paper.
Chinese: 阈值容限图及其补图，被称为共-TT图，由Monma、Reed和Trotter[24]引入。在此基础上，Hell等人[19]引入了负区间的概念。然后他们继续定义了有符号区间有向图/二部图，证明了它们与几个看似不同的有向图/二部图类等价。他们还表明，共-TT图与对称的有符号区间有向图等价，其中一些有向图顶点有环而另一些没有。我们已经证明了这实际上解决了Monma、Reed和Trotter[24]提出的共-TT图的表示特征问题。在这篇论文中，我们分别从它们的双邻接矩阵和邻接矩阵的角度，对有符号区间二部图和有符号区间图进行了特征化。此外，我们强调了有符号区间图的几何表示，即共-TT图。最后，通过利用有符号区间图的几何表示，我们解决了用最小禁止诱导子图来表征共-TT图的开放问题，这个问题最初由Monma、Reed和Trotter在同一篇论文中提出。
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English: Among the symmetries in physics, the rotation symmetry is most familiar to
us. It is known that the spherical harmonics serve useful purposes when the
world is rotated. Squeeze transformations are also becoming more prominent in
physics, particularly in optical sciences and in high-energy physics. As can be
seen from Dirac's light-cone coordinate system, Lorentz boosts are squeeze
transformations. Thus the squeeze transformation is one of the fundamental
transformations in Einstein's Lorentz-covariant world. It is possible to define
a complete set of orthonormal functions defined for one Lorentz frame. It is
shown that the same set can be used for other Lorentz frames. Transformation
properties are discussed. Physical applications are discussed in both optics
and high-energy physics. It is shown that the Lorentz harmonics provide the
mathematical basis for squeezed states of light. It is shown also that the same
set of harmonics can be used for understanding Lorentz-boosted hadrons in
high-energy physics. It is thus possible to transmit physics from one branch of
physics to the other branch using the mathematical basis common to them.
Chinese: 在物理学中的对称性中，旋转对称性是我们最熟悉的。众所周知，当世界发生旋转时，球谐函数会发挥重要作用。压缩变换在物理学中也日益突出，特别是在光学科学和高能物理学中。从狄拉克的光锥坐标系可以看出，洛伦兹变换是压缩变换。因此，压缩变换是爱因斯坦的洛伦兹协变世界中的基本变换之一。可以定义一组完备的正交归一函数，适用于一个洛伦兹参考系。研究表明，这组函数也可以用于其他洛伦兹参考系。讨论了变换性质。在光学和高能物理学中讨论了物理应用。研究表明，洛伦兹谐函数为光的压缩态提供了数学基础。研究还表明，同一组谐函数可以用于理解高能物理学中的洛伦兹变换强子。因此，可以通过它们共有的数学基础将物理学从一个分支传递到另一个分支。
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English: A new algorithm based on auxiliary differential equation and finite
difference time domain method (ADE-FDTD method) is presented to model a
waveguide whose active layer is constituted of a silica matrix doped with
rare-earth and silicon nanograins. The typical lifetime of rare-earth can be as
large as some ms, whereas the electromagnetic field in a visible range and
near-infrared is characterized by a period of the order of fs. Due to the large
difference between these two characteristic times, the conventional ADE-FDTD
method is not suited to treat such systems. A new algorithm is presented so
that the steady state of rare earth and silicon nanograins electronic levels
populations along with the electromagnetic field can be fully described. This
algorithm is stable and applicable to a wide range of optical gain materials in
which large differences of characteristic lifetimes are present.
Chinese: 提出了一种基于辅助微分方程和有限差分时域方法（ADE-FDTD方法）的新算法，用于模拟活性层由掺有稀土和硅纳米颗粒的二氧化硅基质构成的光波导。稀土的典型寿命可达数毫秒，而可见光和近红外范围内的电磁场则具有飞秒量级的周期。由于这两个特征时间之间的巨大差异，传统的ADE-FDTD方法不适用于处理此类系统。提出了一种新算法，使得稀土和硅纳米颗粒电子能级布居数的稳态以及电磁场能够得到充分描述。该算法稳定且适用于具有显著特征寿命差异的各种光学增益材料。
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English: In this paper, we extend the Recurrent Inertial Graph-based Estimator (RING),
a novel neural-network-based solution for Inertial Motion Tracking (IMT), to
generalize across a large range of sampling rates, and we demonstrate that it
can overcome four real-world challenges: inhomogeneous magnetic fields,
sensor-to-segment misalignment, sparse sensor setups, and nonrigid sensor
attachment. RING can estimate the rotational state of a three-segment kinematic
chain with double hinge joints from inertial data, and achieves an experimental
mean-absolute-(tracking)-error of 8.10 +/- 1.19 degrees if all four challenges
are present simultaneously. The network is trained on simulated data yet
evaluated on experimental data, highlighting its remarkable ability to
zero-shot generalize from simulation to experiment. We conduct an ablation
study to analyze the impact of each of the four challenges on RING's
performance, we showcase its robustness to varying sampling rates, and we
demonstrate that RING is capable of real-time operation. This research not only
advances IMT technology by making it more accessible and versatile but also
enhances its potential for new application domains including non-expert use of
sparse IMT with nonrigid sensor attachments in unconstrained environments.
Chinese: 在本文中，我们将基于循环惯性图估计器（RING）——一种用于惯性运动跟踪（IMT）的新型神经网络解决方案——扩展到广泛的采样率范围，并证明它可以克服四个现实挑战：非均匀磁场、传感器与段之间的错位、稀疏传感器设置和非刚性传感器连接。RING可以从惯性数据中估计具有双铰链关节的三段运动链的旋转状态，并且如果同时存在所有四个挑战，则可以实现实验平均绝对（跟踪）误差为8.10 +/- 1.19度。该网络在模拟数据上进行训练，但在实验数据上进行评估，突出了其从模拟到实验的零样本泛化能力的显著能力。我们进行了消融研究，以分析每个挑战对RING性能的影响，展示了其对不同采样率的鲁棒性，并证明RING能够进行实时操作。这项研究不仅通过使其更具可访问性和多功能性来推进IMT技术，还增强了其在包括非专业人员在无约束环境中使用稀疏IMT和非刚性传感器连接的新应用领域的潜力。
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English: We prove an inverse of Furstenberg's correspondence principle stating that
for all measure preserving systems $(X,\mu,T)$ and $A\subset X$ measurable
there exists a set $E \subset \mathbb{N}$ such that \[ \mu\left(
\bigcap_{i=1}^k T^{-n_i}A\right) = \lim_{N\to \infty} \frac{\left|\left(
\bigcap_{i=1}^k (E-n_i) \right)\cap \{0,\dots,N-1\}\right|}{N}\] for all
$k,n_1,\dots,n_k \in \mathbb{N}$. As a corollary we show that a set $R\subset
\mathbb{N}$ is a set of nice recurrence if and only if it is nicely
intersective. Together, the inverse of Furstenberg's correspondence principle
and it's corollary partially answer two questions of Moreira.
Chinese: 我们证明了一个Furstenberg对应原理的逆定理，该定理表明，对于所有测度保持系统$(X,\mu,T)$和$A\subset X$可测集，存在一个集合$E \subset \mathbb{N}$，使得 \[ \mu\left( \bigcap_{i=1}^k T^{-n_i}A \right) = \lim_{N\to \infty} \frac{\left| \left( \bigcap_{i=1}^k (E-n_i) \right) \cap \{0,\dots,N-1\} \right|}{N} \] 对于所有$k,n_1,\dots,n_k \in \mathbb{N}$都成立。作为推论，我们证明了集合$R\subset \mathbb{N}$是良好回归集当且仅当它是良好交集的。综合Furstenberg对应原理的逆定理及其推论，部分回答了Moreira的两个问题。
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English: The gas-phase velocity dispersions in disk galaxies, which trace turbulence
in the interstellar medium, are observed to increase with lookback time.
However, the mechanisms that set this rise in turbulence are observationally
poorly constrained. To address this, we combine kiloparsec-scale ALMA
observations of CO(3-2) and CO(4-3) with HST observations of H$\alpha$ to
characterize the molecular gas and star formation properties of seven local
analogues of main sequence galaxies at $z \sim 1-2$, drawn from the DYNAMO
sample. Investigating the ''molecular gas main sequence'' on kpc-scales, we
find that galaxies in our sample are more gas-rich than local star-forming
galaxies at all disk positions. We measure beam smearing corrected molecular
gas velocity dispersions and relate them to the molecular gas and star
formation rate surface densities. Despite being relatively nearby ($z \sim
0.1$), DYNAMO galaxies exhibit high velocity dispersions and gas and star
formation rate surface densities throughout their disks, when compared to local
star forming samples. Comparing these measurements to predictions from star
formation theory, we find very good agreements with the latest
feedback-regulated star formation models. However, we find that theories which
combine gravitational energy dissipation from radial gas transport with
feedback over-estimate the observed molecular gas velocity dispersions.
Chinese: 星际介质中的气相速度弥散度在盘状星系中，反映了星际介质中的湍流，被观察到随回望时间增加。然而，决定这种湍流上升的机制在观测上约束较差。为了解决这个问题，我们结合了千秒差距尺度的ALMA观测的CO(3-2)和CO(4-3)与HST观测的Hα，以表征七个与主序星系在红移约为1-2的本地星系近似的分子气体和星形成性质。在kpc尺度的“分子气体主序”上研究，我们发现我们样本中的星系在所有盘位置上都比本地星形成星系更富含气体。我们测量了光束弥散校正的分子气体速度弥散度，并将它们与分子气体和星形成率表面密度联系起来。尽管相对较近（红移约为0.1），DYNAMO星系在其整个盘中显示出高速度弥散度和气体和星形成率表面密度，与本地星形成样本相比。将这些测量结果与星形成理论的预测进行比较，我们发现与最新的反馈调节的星形成模型有很好的一致性。然而，我们发现将径向气体输运引起的引力能量耗散与反馈相结合的理论高估了观测到的分子气体速度弥散度。
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English: We obtain a class of slowly rotating charged Kaluza-Klein black hole
solutions of the five-dimensional Einstein-Maxwell-dilaton theory with
arbitrary dilaton coupling constant. At infinity, the spacetime is effectively
four-dimensional. In the absence of the squashing function, our solution
reduces to the five-dimensional asymptotically flat slowly rotating charged
dilaton black hole solution with two equal angular momenta. We calculate the
mass, the angular momentum and the gyromagnetic ratio of these rotating
Kaluza-Klein dilaton black holes. It is shown that the dilaton field and the
non-trivial asymptotic structure of the solutions modify the gyromagnetic ratio
of the black holes. We also find that the gyromagnetic ratio crucially depends
on the dilaton coupling constant, \alpha, and decreases with increasing \alpha
for any size of the compact extra dimension.
Chinese: 我们得到了一类具有任意标量耦合常数的五维爱因斯坦-麦克斯韦-弦理论中的缓慢旋转带电卡鲁扎-克莱因黑洞解。在无穷远处，时空实际上是四维的。在没有挤压函数的情况下，我们的解简化为具有两个相等角动量的五维渐近平坦缓慢旋转带电弦黑洞解。我们计算了这些旋转卡鲁扎-克莱因弦黑洞的质量、角动量和自旋磁比。结果表明，标量场和解的非平凡渐近结构改变了黑洞的自旋磁比。我们还发现，自旋磁比关键地依赖于标量耦合常数α，并且对于任何紧凑额外维度的尺寸，随着α的增加而减小。
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English: This is the first in a series Of papers in which we initiate the study Of
very rough solutions to the initial value problem for the Einstein Vacuum
equations expressed relative to wave coordinates. By very rough we mean
solutions which cannot be constructed by the classical techniques Of energy
estimates and Sobolev inequalities. Following our previous work on quasilinear
wave equations we develop new analytic methods based on Strichartz type
inequalities which results in a gain of half a derivative relative to the
classical result. Thus our result requires only $H^{2+\epsilon}$ regularity for
the data.
Our methods blend paradifferential techniques with a geometric approach to
the derivation of decay estimates. The latter allows us to take full advantage
of the specific structure of the Einstein equations.
Chinese: 这是关于相对波坐标表达的爱因斯坦真空方程初值问题非常粗糙解的一系列论文中的第一篇。当我们说“非常粗糙”时，我们指的是那些不能通过经典技术如能量估计和Sobolev不等式构造的解。在先前关于拟线性波动方程的工作基础上，我们发展了基于Strichartz型不等式的新分析方法，这相对于经典结果来说，增加了一半的导数。因此，我们的结果只需要数据具有$H^{2+\epsilon}$的正则性。
我们的方法将拟微分技术与方法推导衰减估计的几何方法相结合。后者使我们能够充分利用爱因斯坦方程的特定结构。
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English: Software module clustering is an unsupervised learning method used to cluster
software entities (e.g., classes, modules, or files) with similar features. The
obtained clusters may be used to study, analyze, and understand the software
entities' structure and behavior. Implementing software module clustering with
optimal results is challenging. Accordingly, researchers have addressed many
aspects of software module clustering in the past decade. Thus, it is essential
to present the research evidence that has been published in this area. In this
study, 143 research papers from well-known literature databases that examined
software module clustering were reviewed to extract useful data. The obtained
data were then used to answer several research questions regarding
state-of-the-art clustering approaches, applications of clustering in software
engineering, clustering processes, clustering algorithms, and evaluation
methods. Several research gaps and challenges in software module clustering are
discussed in this paper to provide a useful reference for researchers in this
field.
Chinese: 软件模块聚类是一种无监督学习方法，用于对具有相似特征的软件实体（例如类、模块或文件）进行聚类。获得的聚类可用于研究、分析和理解软件实体的结构和行为。实现具有最优结果的软件模块聚类具有挑战性。因此，在过去十年中，研究人员已经解决了软件模块聚类的许多方面。因此，在这个领域呈现已发表的研究证据是至关重要的。在本研究中，我们从知名文献数据库中回顾了143篇研究软件模块聚类的论文，以提取有用的数据。然后使用获得的数据来回答有关最先进的聚类方法、聚类在软件工程中的应用、聚类过程、聚类算法和评估方法的研究问题。本文讨论了软件模块聚类领域的一些研究空白和挑战，为该领域的研究人员提供有用的参考。
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English: Under the Franck-Condon approximation, we systematically validated the
performance of density functional theory (DFT) and the effects of anharmonicity
in simulating C/N/O K-edge vibrationally-resolved X-ray spectra of common
diatomic molecules. To get ``transparent'' validations, vibronic fine
structures of only the lowest 1s excited or ionized state in the X-ray
absorption (XAS) or photoelectron (XPS) spectra were investigated. All 6
systems (N$_2$, N$_2^+$; NO, NO$^+$; CO, CO$^+$) were studied within the
harmonic oscillator (HO) approximation using DFT with four functionals (BLYP,
BP86, B3LYP, M06-2X) for 10 XAS and 4 XPS spectra, and excellent agreement
between theoretical and experimental spectra was found in most systems, except
O1s XAS of NO, CO, and NO$^+$. We analyzed and established a connection between
their complex vibronic structures (many weak oscillating features within a
broad peak) and the significant geometrical changes induced by the O1s hole.
The three spectra were well reproduced with anharmonic (AH) calculations by
using quantum wavepacket dynamics based on potential energy curves (PECs)
generated by DFT methods or multiconfigurational levels, highlighting
sensitivity to the anharmonic effect and the PEC quality. In other examples of
XAS (CO$^+$, C1s and O1s; NO, N1s) corresponding to smaller structural changes,
HO and AH approaches lead to similar fine structures, which are dominated by
0-0 and 0-1 transitions. This study highlights the use of DFT with selected
functionals for such diatomic calculations due to its easy execution and
generally reliable accuracy. Functional dependence in diatomic systems is
generally more pronounced than in polyatomic ones. We found that BLYP, BP86,
and B3LYP functionals consistently exhibited high accuracy in predicting
spectral profiles, bond lengths, and vibrational frequencies, which slightly
outperformed M06-2X.
Chinese: 在Franck-Condon近似下，我们系统地验证了密度泛函理论（DFT）在模拟常见双原子分子C/N/O K边振动分辨X射线光谱中的性能以及非简谐效应对该性能的影响。为了获得“透明”的验证，仅研究了X射线吸收（XAS）或光电子（XPS）光谱中最低1s激发或电离状态的振动精细结构。所有6个系统（N$_2$，N$_2^+$；NO，NO$^+$；CO，CO$^+$）均在谐波振荡器（HO）近似下使用DFT和四种泛函（BLYP，BP86，B3LYP，M06-2X）进行了研究，用于10个XAS和4个XPS光谱，并在大多数系统中发现理论与实验光谱之间有极好的吻合，除了NO，CO和NO$^+$的O1s XAS。我们分析了它们复杂的振动精细结构（宽峰内的许多弱振荡特征）与由O1s空穴引起的显著几何变化之间的联系。这三个光谱通过使用基于由DFT方法或多配置能级生成的势能曲线（PECs）的量子波包动力学（AH）计算得到了很好的再现，突出了对非简谐效应和PEC质量的敏感性。在其他XAS的例子（CO$^+$，C1s和O1s；NO，N1s）中，对应较小的结构变化，HO和AH方法导致了相似的精细结构，主要由0-0和0-1跃迁主导。这项研究强调了在双原子计算中使用DFT和选定泛函的重要性，因为其易于执行且通常具有可靠的精度。在双原子系统中，泛函的依赖性通常比在多原子系统中更为明显。我们发现BLYP，BP86和B3LYP泛函在预测光谱轮廓、键长和振动频率方面一直表现出高精度，略优于M06-2X。
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English: We use the AdS/CFT correspondence to show that the heavy quark (static)
potential in a strongly-coupled plasma develops an imaginary part at finite
temperature. Thus, deeply bound heavy quarkonia states acquire a small nonzero
thermal width when the t'Hooft coupling $\lambda=g^2 N_c \gg 1$ and the number
of colors $N_c \to \infty$. In the dual gravity description, this imaginary
contribution comes from thermal fluctuations around the bottom of the classical
sagging string in the bulk that connects the heavy quarks located at the
boundary. We predict a strong suppression of $\Upsilon$'s in heavy-ion
collisions and discuss how this may be used to estimate the initial
temperature.
Chinese: 我们利用AdS/CFT对应关系表明，在强耦合等离子体中，重夸克（静态）势在有限温度下发展出虚部。因此，深束缚的重夸克onia态在t'Hooft耦合λ=g^2 N_c >> 1和颜色数N_c → ∞时，获得了一个小的非零热宽度。在双引力描述中，这个虚部贡献来自于连接边界处重夸克的 bulk 中经典下垂弦底部的热涨落。我们预测在重离子碰撞中 Υ 的强烈抑制，并讨论如何利用这一点来估计初始温度。
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English: In quantum mechanics time is generally treated as a parameter rather than an
observable. For instance wave functions are treated as extending in space, but
not in time. But from relativity we expect time and space should be treated on
the same basis. What are the effects if time is an observable? Are these
effects observable with current technology?
In earlier work we showed we should see effects in various high energy
scattering processes. We here extend that work to include bound states. The
critical advantage of working with bound states is that the predictions are
significantly more definite, taking the predictions from testable to
falsifiable.
We estimate the time dispersion for hydrogen as $.177$ attoseconds, possibly
below the current threshold for detection. But the time dispersion should scale
as the $3/2$ power of the principle quantum number $n$. Rydberg atoms can have
$n$ of order $100$, implying a boost by a factor of $1000$. This takes the the
time dispersion to $177$ attoseconds, well within reach of current technology.
There are a wide variety of experimental targets: any time-dependent
processes should show effects. Falsification will be technically challenging
(due to the short time scales) but immediate and unambiguous. Confirmation
would have significant implications for attosecond physics, quantum computing
and communications, quantum gravity, and the measurement problem. And would
suggest practical uses in these areas as well as circuit design, high speed
biochemistry, cryptography, fusion research, and any area involving change at
attosecond time scales.
Chinese: 在量子力学中，时间通常被视为一个参数而不是一个可观测量。例如，波函数被视为在空间中延伸，但在时间上不延伸。但是，从相对论的角度来看，我们应该将时间和空间视为同等的基础。如果时间是可观测的，会有什么影响？这些影响是否可以用当前的技术观测到？
在早期的工作中，我们展示了我们应该在各种高能散射过程中看到效应。我们在这里扩展了这项工作，包括束缚态。与束缚态一起工作的关键优势是预测显著更加明确，将预测从可测试转变为可证伪。
我们估计氢的时间分散度为0.177飞秒，可能低于当前检测的阈值。但是，时间分散度应该与主量子数n的3/2次幂成比例。里德伯原子可以有n的数量级为100，这意味着增加了1000倍。这使得时间分散度达到177飞秒，完全在当前技术的范围内。
有各种各样的实验目标：任何时间依赖的过程都应该显示出效应。证伪在技术上具有挑战性（由于时间尺度很短），但立即且明确。确认将具有重大的意义，对飞秒物理学、量子计算和通信、量子引力以及测量问题具有重要意义。并且将建议在这些领域以及电路设计、高速生物化学、密码学、聚变研究以及任何涉及飞秒时间尺度变化的领域有实际应用。
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English: We study the problem of designing adaptive multi-armed bandit algorithms that
perform optimally in both the stochastic setting and the adversarial setting
simultaneously (often known as a best-of-both-world guarantee). A line of
recent works shows that when configured and analyzed properly, the
Follow-the-Regularized-Leader (FTRL) algorithm, originally designed for the
adversarial setting, can in fact optimally adapt to the stochastic setting as
well. Such results, however, critically rely on an assumption that there exists
one unique optimal arm. Recently, Ito (2021) took the first step to remove such
an undesirable uniqueness assumption for one particular FTRL algorithm with the
$\frac{1}{2}$-Tsallis entropy regularizer. In this work, we significantly
improve and generalize this result, showing that uniqueness is unnecessary for
FTRL with a broad family of regularizers and a new learning rate schedule. For
some regularizers, our regret bounds also improve upon prior results even when
uniqueness holds. We further provide an application of our results to the
decoupled exploration and exploitation problem, demonstrating that our
techniques are broadly applicable.
Chinese: 我们研究了设计同时在随机设置和对抗设置中都表现最优的自适应多臂老虎机算法的问题（通常被称为双优保证）。近期一系列工作表明，当正确配置和分析时，最初设计用于对抗设置的跟随正则化领导者（FTRL）算法实际上也能适应最优地适应随机设置。然而，这样的结果严重依赖于存在唯一最优臂的假设。最近，Ito（2021）首先为特定的FTRL算法（带有1/2-Tsallis熵正则化器）去除了这样的不受欢迎的唯一性假设。在本工作中，我们显著改进并推广了这一结果，表明对于广泛类别的正则化器和新的学习率调度，唯一性并非FTRL算法的必要条件。对于某些正则化器，我们的后悔边界在唯一性成立时甚至也能优于先前的结果。我们进一步提供了一个将我们的结果应用于解耦探索与利用问题的应用示例，表明我们的技术具有广泛的应用性。
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English: Aims. Expanding HII regions and propagating shocks are common in the
environment of young high-mass star-forming complexes. They can compress a
pre-existing molecular cloud and trigger the formation of dense cores. We
investigate whether these phenomena can explain the formation of high-mass
protostars within an infrared dark cloud located at the position of G327.3-0.6
in the Galactic plane, in between two large infrared bubbles and two HII
regions. Methods: The region of G327.3-0.6 was imaged at 450 ? m with the CEA
P-ArT\'eMiS bolometer array on the Atacama Pathfinder EXperiment telescope in
Chile. APEX/LABOCA and APEX-2A, and Spitzer/IRAC and MIPS archives data were
used in this study. Results: Ten massive cores were detected in the P-ArT\'eMiS
image, embedded within the infrared dark cloud seen in absorption at both 8 and
24 ?m. Their luminosities and masses indicate that they form high-mass stars.
The kinematical study of the region suggests that the infrared bubbles expand
toward the infrared dark cloud. Conclusions: Under the influence of expanding
bubbles, star formation occurs in the infrared dark areas at the border of HII
regions and infrared bubbles.
Chinese: 研究目标。HII区的扩展和冲击波的传播在年轻的大质量恒星形成复合体的环境中很常见。它们可以压缩现存的分子云并引发致密核的形成。我们研究了这些现象能否解释位于银河平面G327.3-0.6位置的红外暗云中高质星原的形成，该红外暗云位于两个大型红外气泡和两个HII区之间。
方法：使用智利阿塔卡马路径finder实验望远镜上的CEA P-ArT\'eMiS辐射计阵列对G327.3-0.6区域进行了450微米的成像。本研究使用了APEX/LABOCA和APEX-2A，以及Spitzer/IRAC和MIPS档案数据。
结果：在P-ArT\'eMiS图像中检测到10个质量大的核心，嵌入在在8微米和24微米处可见吸收的红外暗云中。它们的亮度和质量表明它们正在形成大质量恒星。该区域的动力学研究表明红外气泡正朝着红外暗云扩展。
结论：在气泡扩展的影响下，恒星形成发生在HII区和红外气泡边界处的红外暗区。
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English: Face Image Quality Assessment (FIQA) estimates the utility of face images for
automated face recognition (FR) systems. We propose in this work a novel
approach to assess the quality of face images based on inspecting the required
changes in the pre-trained FR model weights to minimize differences between
testing samples and the distribution of the FR training dataset. To achieve
that, we propose quantifying the discrepancy in Batch Normalization statistics
(BNS), including mean and variance, between those recorded during FR training
and those obtained by processing testing samples through the pretrained FR
model. We then generate gradient magnitudes of pretrained FR weights by
backpropagating the BNS through the pretrained model. The cumulative absolute
sum of these gradient magnitudes serves as the FIQ for our approach. Through
comprehensive experimentation, we demonstrate the effectiveness of our
training-free and quality labeling-free approach, achieving competitive
performance to recent state-of-theart FIQA approaches without relying on
quality labeling, the need to train regression networks, specialized
architectures, or designing and optimizing specific loss functions.
Chinese: 面部图像质量评估（FIQA）估计面部图像在自动化面部识别（FR）系统中的效用。我们在本研究中提出了一种基于检查预训练FR模型权重所需变化以最小化测试样本与FR训练数据集分布之间差异的新型方法来评估面部图像的质量。为了实现这一点，我们提出量化FR训练期间记录的批归一化统计（BNS），包括均值和方差，与通过预训练FR模型处理测试样本获得的BNS之间的差异。然后，我们通过反向传播BNS通过预训练模型来生成预训练FR权重的梯度幅度。这些梯度幅度的累积绝对和作为我们方法中的FIQ。通过全面的实验，我们证明了我们的无需训练和无需质量标签的方法的有效性，在不依赖质量标签、训练回归网络、专用架构或设计优化特定损失函数的情况下，实现了与最近最先进FIQA方法的竞争力表现。
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English: Streaked photoelectron emission spectra access the correlated dynamics of
photoelectrons and residual target electrons with attosecond temporal
resolution. We calculated ab initio single-ionization spectra for photoemission
from helium atoms by co-linearly polarized ultrashort XUV and assisting
few-femtosecond IR pulses. Distinguishing direct and shake-up ionization
resulting in ground-state and excited (n=2,3) He+ residual ions, respectively,
we examined the effects of the correlated photoemission dynamics on the
photoelectron phase-accumulation as a function of the observable photoelectron
detection direction and kinetic energy, and XUV-IR pulse delay. We tracked the
dynamical evolution of the residual ion in relative streaked photoemission
delays and found dominant contributions for shake-up emission from the residual
ion - photoelectron interaction. These are in very good and fair agreement,
respectively, for n=2 and n=3 shake-up photoemission along the
pulse-polarization directions, with previous experimental and theoretical
investigations [Ossiander et. al. 2017] and reveal a strong
photoemission-direction dependence for shake-up ionization due to the coupling
between the photoelectron and evolving residual-ion charge distribution in the
IR-laser field.
Chinese: 条纹光电子发射光谱以飞秒时间分辨率揭示了光电子和剩余靶电子的相关动力学。我们通过共线偏振的超短XUV和辅助的飞秒IR脉冲计算了氦原子光电发射的从头算单电离光谱。区分直接和激发（n=2,3）He+剩余离子的激发态和基态电离，我们研究了相关光电发射动力学对光电子相位积累的影响，这取决于可观测的光电子检测方向、动能以及XUV-IR脉冲延迟。我们在相对条纹光电发射延迟中追踪了剩余离子的动态演化，并发现了来自剩余离子-光电子相互作用的激发发射的主要贡献。这些贡献在n=2和n=3激发发射沿脉冲偏振方向上分别非常好和相当好地与先前的实验和理论研究[Ossiander等人，2017]一致，并揭示了由于光电子与红外激光场中演变的剩余离子电荷分布之间的耦合，激发电离对光电发射方向的强烈依赖性。
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English: We study the linear quadratic Gaussian (LQG) control problem, in which the
controller's observation of the system state is such that a desired cost is
unattainable. To achieve the desired LQG cost, we introduce a communication
link from the observer (encoder) to the controller. We investigate the optimal
trade-off between the improved LQG cost and the consumed communication
(information) resources, measured with the conditional directed information,
across all encoding-decoding policies. The main result is a semidefinite
programming formulation for that optimization problem in the finite-horizon
scenario, which applies to time-varying linear dynamical systems. This result
extends a seminal work by Tanaka et al., where the only information the
controller knows about the system state arrives via a communication channel, to
the scenario where the controller has also access to a noisy observation of the
system state. As part of our derivation to show the optimiality of an encoder
that transmits a memoryless Gaussian measurement of the state, we show that the
presence of the controller's observations at the encoder can not reduce the
minimal directed information. For time-invariant systems, where the optimal
policy may be time-varying, we show in the infinite-horizon scenario that the
optimal policy is time-invariant and can be computed explicitly from a solution
of a finite-dimensional semidefinite programming. The results are demonstrated
via examples that show that even low-quality measurements can have a
significant impact on the required communication resources.
Chinese: 我们研究线性二次高斯（LQG）控制问题，其中控制器的系统状态观测使得期望的成本无法实现。为了实现期望的LQG成本，我们从观测器（编码器）到控制器引入了一个通信链路。我们研究了改进的LQG成本与消耗的通信（信息）资源之间的最优权衡，这些资源是通过条件有向信息来衡量的，涉及所有编码-解码策略。主要结果是，在有限时间范围场景下，该优化问题的半定规划公式，适用于时变线性动态系统。这一结果扩展了Tanaka等人的一项开创性工作，在该工作中，控制器关于系统状态的唯一信息是通过通信渠道获得的，到控制器也有权访问系统状态的噪声观测的场景。作为我们推导的一部分，以证明传输状态无记忆高斯测量的编码器的最优性，我们表明控制器在编码器处的观测存在不能减少最小有向信息。对于最优策略可能随时间变化的时不变系统，我们在无限时间范围场景中表明，最优策略是时不变的，并且可以从有限维半定规划解中显式计算。通过示例证明了这些结果，这些示例表明，即使是低质量的测量也可能对所需的通信资源产生重大影响。
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English: In a large transverse field, there is an energy cost associated with flipping
spins along the axis of the field. This penalty can be employed to relate the
transverse-field Ising model in a large field to the XY model in no field (when
measurements are performed at the right stroboscopic times). We describe the
details for how this relationship works and, in particular, we also show under
what circumstances it fails. We examine wavefunction overlap between the two
models and observables, such as spin-spin Green's functions. In general, the
mapping is quite robust at short times, but will ultimately fail if the run
time becomes too long. There is also a trade-off between the length of time one
can run a simulation out to and the time jitter of the stroboscopic
measurements that must be balanced when planning to employ this mapping.
Chinese: 在强横向磁场中，沿磁场轴翻转自旋存在能量成本。这种惩罚可用于将强横向磁场下的伊辛模型与无磁场下的XY模型（当在合适的同步测量时间进行测量时）联系起来。我们详细描述了这种关系的运作机制，并特别指出在何种情况下该关系失效。我们考察了两个模型之间的波函数重叠以及自旋-自旋格林函数等可观测量。通常情况下，该映射在短时内非常稳健，但如果运行时间过长，最终会失效。此外，在同步测量中存在时间抖动，在计划使用该映射时，需要平衡模拟运行时长与时间抖动之间的权衡。
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English: We give a separation bound for an isolated multiple root $x$ of a square
multivariate analytic system $f$ satisfying that an operator deduced by adding
$Df(x)$ and a projection of $D^2f(x)$ in a direction of the kernel of $Df(x)$
is invertible. We prove that the deflation process applied on $f$ and this kind
of roots terminates after only one iteration. When $x$ is only given
approximately, we give a numerical criterion for isolating a cluster of zeros
of $f$ near $x$. We also propose a lower bound of the number of roots in the
cluster.
Chinese: 我们为满足以下条件的平方多变量解析系统$f$的孤立多重根$x$给出了一个分离界限：由将$Df(x)$与$D^2f(x)$在$Df(x)$核方向上的投影相加得到的算子是可逆的。我们证明，在$f$上应用的单次迭代就足以终止这种根的缩并过程。当$x$仅给出近似值时，我们给出了一个数值标准，用于隔离$f$在$x$附近的零点簇。我们还提出了簇中根的数量的下界。
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English: We present an agent-based model that explores the relationship between
pro-family and prosocial behaviors and their impact on settlement formation.
The objective is to investigate how the technological level and various
constraints influence the transition from pro-family to prosocial behavior. The
model incorporates factors such as the specialization requirements of the
technology, societal tolerance, and dynamic interactions within a synthetic
population, where individuals have the choice to prioritize either their family
or their own settlement. Agents' fitness is determined by two components: the
proportion of pro-family agents within their family and the fraction of
prosocial agents in their settlement, as well as its size. Our findings reveal
that the transition from pro-family to prosocial behavior is driven by the
technological level, and the developmental requirements of the technology shape
the smoothness of this transition, ranging from abrupt to gradual. These
results emphasize the significance of considering the interplay between the
technological level, the nature of the technology, and cultural influences when
examining settlement patterns and the dynamics of pro-family and prosocial
behaviors in human societies.
Chinese: 我们提出了一种基于代理的模型，该模型探讨了亲家庭和亲社会行为之间的关系及其对定居地形成的影响。目标是研究技术水平和各种约束如何影响从亲家庭到亲社会行为的转变。该模型纳入了诸如技术专业化的要求、社会容忍度以及在一个合成人口中的动态互动等因素，在这个合成人口中，个体可以选择优先考虑他们的家庭或他们自己的定居地。代理的适应性由两个组成部分决定：他们家庭中亲家庭代理的比例以及他们定居地中亲社会代理的比例，以及其规模。我们的发现表明，从亲家庭到亲社会行为的转变是由技术水平驱动的，技术的发展要求决定了这一转变的平滑程度，从突然到逐渐。这些结果强调了在研究人类社会中定居模式以及亲家庭和亲社会行为的动态时，考虑技术水平、技术的本质和文化影响之间相互作用的重要性。
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English: Let $R=\oplus_{i\in \N_0}R_n$ be a standard graded ring, $R_+ :=\oplus_{i\in
\N}R_n$ be the irrelevant ideal of $R$ and $\fa_0$ be an ideal of $R_0$. In
this paper, as a generalization of the concept of Castelnouvo-Mumford
regularity $\reg(M)$ of a finitely generated graded $R$-module $M$, we define
the regularity of $M$ with respect to $\fa_0+ R_+$, say $\reg_{\fa_0+ R_+}(M)$.
And we study some relations of this new invariant with the classic one. To this
end, we need to consider the cohomological dimension of some finitely generated
$R_0$-modules. Also, we will express $\reg_{\fa_0+ R_+}(M)$ in terms of some
invariants of the minimal graded free resolution of $M$ and see that in a
special case this invariant is independent of the choice of $\fa_0$.
Chinese: 令 $R=\oplus_{i\in \N_0}R_n$ 为一个标准分次环，$R_+ :=\oplus_{i\in \N}R_n$ 为 $R$ 的非相关理想，$\fa_0$ 为 $R_0$ 的一个理想。在本文中，作为有限生成分次 $R$-模块 $M$ 的 Castelnouvo-Mumford 正则性 $\reg(M)$ 的推广，我们定义了 $M$ 关于 $\fa_0+ R_+$ 的正则性，记为 $\reg_{\fa_0+ R_+}(M)$。我们研究了这个新不变量与经典不变量之间的一些关系。为此，我们需要考虑一些有限生成 $R_0$-模块的层维数。此外，我们将用 $M$ 的最小分次自由分解的一些不变量来表示 $\reg_{\fa_0+ R_+}(M)$，并观察到在一种特殊情况下，这个不变量与 $\fa_0$ 的选择无关。
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English: Determining reliable distances to classical novae is a challenging but
crucial step in deriving their ejected masses and explosion energetics. Here we
combine radio expansion measurements from the Karl G. Jansky Very Large Array
with velocities derived from optical spectra to estimate an expansion parallax
for nova V959 Mon, the first nova discovered through its gamma-ray emission. We
spatially resolve the nova at frequencies of 4.5-36.5 GHz in nine different
imaging epochs. The first five epochs cover the expansion of the ejecta from
2012 October to 2013 January, while the final four epochs span 2014 February to
2014 May. These observations correspond to days 126 through 199 and days 615
through 703 after the first detection of the nova. The images clearly show a
non-spherical ejecta geometry. Utilizing ejecta velocities derived from 3D
modelling of optical spectroscopy, the radio expansion implies a distance
between 0.9 +/- 0.2 and 2.2 +/- 0.4 kpc, with a most probable distance of 1.4
+/- 0.4 kpc. This distance implies a gamma-ray luminosity much less than the
prototype gamma-ray-detected nova, V407 Cyg, possibly due to the lack of a red
giant companion in the V959 Mon system. V959 Mon also has a much lower
gamma-ray luminosity than other classical novae detected in gamma-rays to date,
indicating a range of at least a factor of 10 in the gamma-ray luminosities for
these explosions.
Chinese: 确定经典新星的可靠距离是推导其喷射质量和爆炸能量的关键步骤。在这里，我们将凯尔·G·詹斯基甚大天线阵的射电膨胀测量与从光学光谱推导出的速度结合起来，以估计新星V959 Mon的膨胀视差——这是首个通过其伽马射线发射被发现的新星。我们在九个不同的成像时期，在4.5-36.5 GHz的频率上空间分辨了这颗新星。前五个时期覆盖了2012年10月至2013年1月的喷射物膨胀，而最后四个时期跨越了2014年2月至2014年5月。这些观测对应于新星首次被发现后的第126天至第199天，以及第615天至第703天。图像清晰地显示了一个非球形的喷射物几何形状。利用从光学光谱的三维建模中推导出的喷射物速度，射电膨胀表明距离在0.9 +/- 0.2至2.2 +/- 0.4千帕之间，最可能的距离为1.4 +/- 0.4千帕。这个距离意味着其伽马射线亮度远低于原型伽马射线探测新星V407 Cyg，这可能是由于V959 Mon系统中缺乏红巨星伴星。V959 Mon的伽马射线亮度也远低于迄今为止通过伽马射线探测到的其他经典新星，这表明这些爆炸的伽马射线亮度至少相差一个数量级。
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English: Topological materials in crystal solids, including topological insulators
(TIs), topological crystalline insulators (TCIs), topological Dirac semimetals
(DSMs), topological Weyl semimetals (WSMs), topological Dirac or Weyl nodal
line semimetals (NLSMs) and beyond, are mainly featured with topological,
protected non-trivial surface states, and their bulk phases are insulators or
semimetals with the proper presence of Dirac cones, Weyl nodes or Dirac nodal
lines around the Fermi level. The author suggests a two-step computational
screening strategy of 3D topological materials by mixing chemistry with physics
with the considerations of fully filled bands and band inversion.
Chinese: 晶体固体中的拓扑材料，包括拓扑绝缘体（TIs）、拓扑晶体绝缘体（TCIs）、拓扑狄拉克半金属（DSMs）、拓扑魏尔半金属（WSMs）、拓扑狄拉克或魏尔节点线半金属（NLSMs）以及更多，它们的主要特征是拓扑、受保护的非常规表面态，并且它们的体相是具有适当费米能级周围狄拉克锥、魏尔节点或狄拉克节点线的绝缘体或半金属。作者提出了一种将化学与物理相结合的3D拓扑材料两步计算筛选策略，考虑到完全填满的能带和能带反转。
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English: We consider the distribution of the values at real points of random functions
which belong to the Herglotz-Pick (HP) class of analytic mappings of the upper
half plane into itself. It is shown that under mild stationarity assumptions
the individual values of HP functions with singular spectra have a Cauchy type
distribution. The statement applies to the diagonal matrix elements of random
operators, and holds regardless of the presence or not of level repulsion, i.e.
applies to both random matrix and Poisson-type spectra.
Chinese: 我们考虑属于上半平面到自身解析映射的Herglotz-Pick (HP)类随机函数的实点处的值分布。在轻微的平稳性假设下，具有奇异频谱的HP函数的个别值具有柯西型分布。这一结论适用于随机算子的对角矩阵元素，并且不受能级排斥（即随机矩阵或泊松型频谱）的存在与否的影响。
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English: In multi-agent applications such as surveillance and logistics, fleets of
mobile agents are often expected to coordinate and safely visit a large number
of goal locations as efficiently as possible. The multi-agent planning problem
in these applications involves allocating and sequencing goals for each agent
while simultaneously producing conflict-free paths for the agents. In this
article, we introduce a new algorithm called MS* which computes an optimal
solution for this multi-agent problem by fusing and advancing state of the art
solvers for multi-agent path finding (MAPF) and multiple travelling salesman
problem (mTSP). MS* leverages our prior subdimensional expansion approach for
MAPF and embeds the mTSP solvers to optimally allocate and sequence goals for
agents. Numerical results show that our new algorithm can solve the multi-agent
problem with 20 agents and 50 goals in a minute of CPU time on a standard
laptop.
Chinese: 在多智能体应用，如监控和物流中，通常期望移动智能体队伍能够尽可能高效地协调并安全地访问大量目标地点。这些应用中的多智能体规划问题涉及为每个智能体分配和排序目标，同时为智能体生成无冲突的路径。在本文中，我们介绍了一种名为MS*的新算法，该算法通过融合和推进多智能体路径寻找（MAPF）和多重旅行商问题（mTSP）的最先进求解器，为这个多智能体问题计算出一个最优解。MS*利用了我们之前为MAPF的子维度扩展方法，并嵌入mTSP求解器以最优地分配和排序智能体的目标。数值结果表明，我们的新算法可以在标准笔记本电脑上以一分钟CPU时间解决包含20个智能体和50个目标的多个智能体问题。
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English: Deep Learning has implemented a wide range of applications and has become
increasingly popular in recent years. The goal of multimodal deep learning is
to create models that can process and link information using various
modalities. Despite the extensive development made for unimodal learning, it
still cannot cover all the aspects of human learning. Multimodal learning helps
to understand and analyze better when various senses are engaged in the
processing of information. This paper focuses on multiple types of modalities,
i.e., image, video, text, audio, body gestures, facial expressions, and
physiological signals. Detailed analysis of past and current baseline
approaches and an in-depth study of recent advancements in multimodal deep
learning applications has been provided. A fine-grained taxonomy of various
multimodal deep learning applications is proposed, elaborating on different
applications in more depth. Architectures and datasets used in these
applications are also discussed, along with their evaluation metrics. Last,
main issues are highlighted separately for each domain along with their
possible future research directions.
Chinese: 深度学习已经实现了广泛的应用，并在近年来变得越来越受欢迎。多模态深度学习的目标是创建能够使用各种模态处理和链接信息的模型。尽管为了单模态学习已经取得了广泛的发展，但它仍然无法涵盖人类学习的所有方面。多模态学习有助于在处理信息时，当各种感官被参与时，更好地理解和分析。本文重点研究了多种类型的模态，即图像、视频、文本、音频、身体姿态、面部表情和生理信号。对过去和当前的基线方法进行了详细分析，并对多模态深度学习应用中的最新进展进行了深入研究。提出了各种多模态深度学习应用的细粒度分类法，并更深入地阐述了不同的应用。还讨论了这些应用中使用的架构和数据集，以及它们的评估指标。最后，针对每个领域的主要问题分别进行了突出，并指出了它们可能的未来研究方向。
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English: We prove that in every ring of generalised power series with non-positive
real exponents and coefficients in a field of characteristic zero, every series
admits a factorisation into finitely many irreducibles of infinite support, the
number of which can be bounded in terms of the order type of the series, and a
unique product, up to multiplication by a unit, of factors of finite support.
We deduce analogous results for the ring of omnific integers within Conway's
surreal numbers, using a suitable notion of infinite product. In turn, we solve
Gonshor's conjecture that the omnific integer $\omega^{\sqrt{2}} + \omega + 1$
is prime.
We also exhibit new classes of irreducible and prime generalised power series
and omnific integers, generalising previous work of Berarducci and Pitteloud.
Chinese: 我们证明，在具有非正实指数和特征零域系数的广义幂级数环中，每个级数都允许分解为有限多个无限支撑的不可约元，其数量可由级数的序类型所界定，并且具有有限支撑的因子的唯一乘积（不计乘以单位元的差异）。
我们利用适当的无限乘积概念，推导出康威超实数环中全整数环的类似结果。进而，我们解决了Gonshor猜想，即全整数ω^√2 + ω + 1是素数。
我们还展示了新的不可约和素数广义幂级数及全整数类，推广了Berarducci和Pitteloud之前的工作。
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English: The structural, electronic, optical and elastic properties of perovskites of
the $\alpha$-, $\beta$- and $\gamma$-phase family CsSnI$_{3-x}$Cl$_x$ (x = 0,
1, 2, 3) are analyzed by ab initio methods using GGA, SCAN and HSE06. It is
found that the lattice constants of CsSnI$_{3-x}$Cl$_x$ decrease with
decreasing anion size from I to Cl, and when passing from CsSnI$_3$ to
CsSnCl$_3$, the band gap width decreases slightly at the beginning and then
increases. The optical characteristics were evaluated and it was found that the
$\alpha$-, $\beta$-phase of CsSnI$_{3-x}$Cl$_x$ at $x=1$ has a wide absorption
range and high absorption coefficients compared to other Cl concentrations. The
elastic constants of $\alpha$-CsSnI$_{3-x}$Cl$_x$ perovskite have been
calculated and their bulk moduli, shear moduli, sound velocities and Debye
temperatures under pressure in the range from 0 to 30 GPa have been considered,
with the external pressure induction increasing in steps of 5 GPa. These
materials are found to be mechanically stable perovskites according to Born
stability criteria and low bulk moduli. Thus, we predict that perovskites of
the CsSnI$_{3-x}$Cl$_x$ family are good candidates for optical materials used
in solar cells.
Chinese: 使用GGA、SCAN和HSE06方法通过从头计算方法分析了$\alpha$、$\beta$和$\gamma$相家族的钙钛矿CsSnI$_{3-x}$Cl$_x$（x = 0，1，2，3）的结构、电子、光学和弹性性质。研究发现，随着阴离子尺寸从I减小到Cl，CsSnI$_{3-x}$Cl$_x$的晶格常数减小，并且在从CsSnI$_3$过渡到CsSnCl$_3$的过程中，带隙宽度最初略有减小，然后又增加。评估了光学特性，发现与其它Cl浓度相比，当x=1时，CsSnI$_{3-x}$Cl$_x$的$\alpha$、$\beta$相具有较宽的吸收范围和高吸收系数。计算了$\alpha$-CsSnI$_{3-x}$Cl$_x$钙钛矿的弹性常数，并考虑了在0到30 GPa的压力范围内其体积模量、剪切模量、声速和德拜温度，外部压力以5 GPa的步长增加。根据Born稳定性准则和低体积模量，这些材料被认定为机械稳定的钙钛矿。因此，我们预测CsSnI$_{3-x}$Cl$_x$家族的钙钛矿是用于太阳能电池的光学材料的良好候选者。
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English: Let $\Delta$ be an oriented valued graph equipped with a group of admissible
automorphisms satisfying a certain stability condition. We prove that the
(coefficient-free) cluster algebra $\mathcal A(\Delta/G)$ associated to the
valued quotient graph $\Delta/G$ is a subalgebra of the quotient $\pi(\mathcal
A(\Delta))$ of the cluster algebra associated to $\Delta$ by the action of $G$.
When $\Delta$ is a Dynkin diagram, we prove that $\mathcal A(\Delta/G)$ and
$\pi(\mathcal A(\Delta))$ coincide. As an example of application, we prove that
affine valued graphs are mutation-finite, giving an alternative proof to a
result of Seven.
Chinese: 设 $\Delta$ 是一个带有满足特定稳定性条件的可接受自同构群的有向值图。我们证明，与值商图 $\Delta/G$ 相关的无系数簇代数 $\mathcal A(\Delta/G)$ 是由 $G$ 作用得到的 $\Delta$ 相关的簇代数 $\mathcal A(\Delta)$ 的商 $\pi(\mathcal A(\Delta))$ 的一个子代数。当 $\Delta$ 是 Dynkin 图时，我们证明 $\mathcal A(\Delta/G)$ 和 $\pi(\mathcal A(\Delta))$ 相等。作为应用实例，我们证明仿射值图是突变有限的，从而给出了 Seven 结果的一个替代证明。
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English: Let $\Bbbk$ be any field of characteristic zero, $X$ be a del Pezzo surface
and $G$ be a finite subgroup in $\operatorname{Aut}(X)$. In this paper we study
when the quotient surface $X / G$ can be non-rational over $\Bbbk$. Obviously,
if there are no smooth $\Bbbk$-points on $X / G$ then it is not
$\Bbbk$-rational. Therefore under assumption that the set of smooth
$\Bbbk$-points on $X / G$ is not empty we show that there are few possibilities
for non-$\Bbbk$-rational quotients.
The quotients of del Pezzo surfaces of degree $2$ and greater are considered
in the author's previous papers. In this paper we study the quotients of del
Pezzo surfaces of degree $1$. We show that they can be non-$\Bbbk$-rational
only for the trivial group or cyclic groups of order $2$, $3$ and $6$. For the
trivial group and the group of order $2$ we show that both $X$ and $X / G$ are
not $\Bbbk$-rational if the $G$-invariant Picard number of $X$ is $1$. For the
groups of order $3$ and $6$ we construct examples of both $\Bbbk$-rational and
non-$\Bbbk$-rational quotients of both $\Bbbk$-rational and
non-$\Bbbk$-rational del Pezzo surfaces of degree $1$ such that the
$G$-invariant Picard number of $X$ is $1$.
As a result of complete classification of non-$\Bbbk$-rational quotients of
del Pezzo surfaces we classify surfaces that are birationally equivalent to
quotients of $\Bbbk$-rational surfaces, and obtain some corollaries concerning
fields of invariants of $\Bbbk(x , y)$.
Chinese: 设 $\Bbbk$ 是任何零特征域，$X$ 是一个德尔·佩佐曲面，$G$ 是 $\operatorname{Aut}(X)$ 中的一个有限子群。在这篇论文中，我们研究当商曲面 $X / G$ 在 $\Bbbk$ 上非有理时的情况。显然，如果 $X / G$ 上没有光滑的 $\Bbbk$-点，那么它不是 $\Bbbk$-有理的。因此，在假设 $X / G$ 上的光滑 $\Bbbk$-点集非空的情况下，我们表明非 $\Bbbk$-有理商的可能性很少。
作者在之前的论文中考虑了度数为 $2$ 及以上的德尔·佩佐曲面的商。在这篇论文中，我们研究度数为 $1$ 的德尔·佩佐曲面的商。我们表明，它们只有在平凡群或阶为 $2$、$3$ 和 $6$ 的循环群的情况下才可能是非 $\Bbbk$-有理的。对于平凡群和阶为 $2$ 的群，我们证明如果 $X$ 的 $G$-不变皮卡德数为 $1$，那么 $X$ 和 $X / G$ 都不是 $\Bbbk$-有理的。对于阶为 $3$ 和 $6$ 的群，我们构造了 $\Bbbk$-有理和非 $\Bbbk$-有理的德尔·佩佐曲面（度数为 $1$）的商的例子，使得 $X$ 的 $G$-不变皮卡德数为 $1$。
作为德尔·佩佐曲面非 $\Bbbk$-有理商的完全分类的结果，我们分类了与 $\Bbbk$-有理曲面商双有理等价的曲面，并得到了一些关于 $\Bbbk(x, y)$ 的不变域场的推论。
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English: \Xe{136} is used as the target medium for many experiments searching for
\bbnonu. Despite underground operation, cosmic muons that reach the laboratory
can produce spallation neutrons causing activation of detector materials. A
potential background that is difficult to veto using muon tagging comes in the
form of \Xe{137} created by the capture of neutrons on \Xe{136}. This isotope
decays via beta decay with a half-life of 3.8 minutes and a \Qb\ of $\sim$4.16
MeV. This work proposes and explores the concept of adding a small percentage
of \He{3} to xenon as a means to capture thermal neutrons and reduce the number
of activations in the detector volume. When using this technique we find the
contamination from \Xe{137} activation can be reduced to negligible levels in
tonne and multi-tonne scale high pressure gas xenon neutrinoless double beta
decay experiments running at any depth in an underground laboratory.
Chinese: \Xe{136}被用作许多寻找\bbnonu实验的目标介质。尽管在地下运行，到达实验室的宇宙射线中子可以产生裂变中子，导致探测器材料活化。一种难以通过中子标记来消除的潜在背景是由\Xe{136}上的中子俘获产生的\Xe{137}。这种同位素通过β衰变进行衰变，半衰期为3.8分钟，Q值约为4.16 MeV。这项工作提出并探索了向氙中添加少量\He{3}的概念，作为一种捕获热中子并减少探测器体积中活化的方法。在使用这种技术时，我们发现\Xe{137}活化的污染可以减少到在地下实验室中以任何深度运行的吨级和兆吨级高压氙中微子双β衰变实验中可以忽略的水平。
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English: Micromagnetic beads are widely used in biomedical applications for cell
separation, drug delivery, and hypothermia cancer treatment. Here we propose to
use self-organized magnetic bead structures which accumulate on fixed magnetic
seeding points to isolate circulating tumor cells. The analysis of circulating
tumor cells is an emerging tool for cancer biology research and clinical cancer
management including the detection, diagnosis and monitoring of cancer.
Microfluidic chips for isolating circulating tumor cells use either affinity,
size or density capturing methods. We combine multiphysics simulation
techniques to understand the microscopic behavior of magnetic beads interacting
with Nickel accumulation points used in lab-on-chip technologies. Our proposed
chip technology offers the possibility to combine affinity and size capturing
with special antibody-coated bead arrangements using a magnetic gradient field
created by Neodymium Iron Boron permanent magnets. The multiscale simulation
environment combines magnetic field computation, fluid dynamics and discrete
particle dynamics.
Chinese: 微磁珠在生物医学应用中广泛用于细胞分离、药物递送和低温癌症治疗。在这里，我们提出使用自我组织的磁珠结构，这些结构在固定的磁种子点上积累，以隔离循环肿瘤细胞。循环肿瘤细胞的分析是癌症生物学研究和临床癌症管理中的一种新兴工具，包括癌症的检测、诊断和监测。用于隔离循环肿瘤细胞的微流控芯片采用亲和力、尺寸或密度捕获方法。我们结合多物理场模拟技术来理解磁珠与实验室芯片技术中使用的镍积累点相互作用的微观行为。我们提出的芯片技术提供了结合亲和力和尺寸捕获的可能性，使用由钕铁硼永磁体产生的磁梯度场，通过特殊的抗体包被磁珠排列。多尺度模拟环境结合了磁场计算、流体动力学和离散粒子动力学。
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English: In this note we describe a general elementary procedure to attach a fusion
ring to any Kac-Moody algebra of affine type. In the case of untwisted affine
algebras, they are usual fusion rings in the literature. In the case of twisted
affine algebras, they are exactly the twisted fusion rings defined by the
author in [Ho2] via tracing out diagram automorphisms on conformal blocks for
appropriate simply-laced Lie algebras. We also relate the fusion ring to the
modular S-matrix for any Kac-Moody algebra of affine type.
Chinese: 在这篇笔记中，我们描述了一种通用的基本方法，将融合环附加到任何仿射类型的Kac-Moody代数。在非扭曲仿射代数的情况下，它们是文献中常见的融合环。在扭曲仿射代数的情况下，它们正是作者在[Ho2]中通过追踪适当简单斜Lie代数的共形块上的图自同构所定义的扭曲融合环。我们还把融合环与任何仿射类型Kac-Moody代数的模S矩阵联系起来。
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English: Semantic communication allows the receiver to know the intention instead of
the bit information itself, which is an emerging technique to support real-time
human-machine and machine-to-machine interactions for future wireless
communications. In semantic communications, both transmitter and receiver share
some common knowledge, which can be used to extract small-size information at
the transmitter and recover the original information at the receiver. Due to
different design purposes, security issues in semantic communications have two
unique features compared to standard bit-wise communications. First, an
attacker in semantic communications considers not only the amount of stolen
data but also the meanings of stolen data. Second, an attacker in semantic
communication systems can attack not only semantic information transmission as
done in standard communication systems but also attacks machine learning (ML)
models used for semantic information extraction since most of semantic
information is generated using ML based methods. Due to these unique features,
in this paper, we present an overview on the fundamentals and key challenges in
the design of secure semantic communication. We first provide various methods
to define and extract semantic information. Then, we focus on secure semantic
communication techniques in two areas: information security and semantic ML
model security. For each area, we identify the main problems and challenges.
Then, we will provide a comprehensive treatment of these problems. In a
nutshell,this article provides a holistic set of guidelines on how to design
secure semantic communication systems over real-world wireless communication
networks.
Chinese: 语义通信允许接收者了解意图而不是比特信息本身，这是一种支持未来无线通信中实时人机交互和机机交互的新兴技术。在语义通信中，发送者和接收者共享一些共同知识，这些知识可以用于在发送端提取小型信息，并在接收端恢复原始信息。由于不同的设计目的，与标准位操作通信相比，语义通信中的安全问题有两个独特的特点。首先，语义通信中的攻击者不仅考虑被盗数据量，还考虑被盗数据的含义。其次，语义通信系统中的攻击者不仅可以攻击像标准通信系统中所做的那样语义信息传输，还可以攻击用于语义信息提取的机器学习（ML）模型，因为大多数语义信息都是使用基于ML的方法生成的。由于这些独特特点，在本文中，我们概述了安全语义通信设计的基础和关键挑战。我们首先提供了定义和提取语义信息的各种方法。然后，我们关注两个领域的安全语义通信技术：信息安全语义和语义ML模型安全。对于每个领域，我们确定了主要问题和挑战。然后，我们将对这些问题进行全面的探讨。总之，本文提供了一套全面的指南，说明如何在现实世界的无线通信网络上设计安全的语义通信系统。
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English: We numerically study the SU(2)$\otimes$SU(2) symmetric spin-orbit coupled
model as a lower symmetric generalization of the SU(4) exchange model. On the
symmetric line with respect to the spin and orbit, our result shows the
essentially singular gap formation in consistent with the analytic approach,
which is different from the previous numerical calculation. Furthermore, we
find new critical phases around the SU(4) point, surrounding the previously
known gapless symmetric line. In these novel phases either spin or orbital
excitations around momentum $q=\pi$ form massless continua which split from the
excitations belonging to the $[2^2]$ irreducible representation at the SU(4)
point. On the critical symmetric line, the additional coupled spin-orbit
excitations around $q=\pi/2$ originating from [$2^11^2$] become critical, too.
Chinese: 我们数值研究了SU(2)×SU(2)对称的自旋轨道耦合模型，将其作为SU(4)交换模型的下对称推广。在自旋和轨道对称的线上，我们的结果表明，与解析方法一致，存在本质上奇异的能隙形成，这与之前的数值计算不同。此外，我们在SU(4)点周围发现了新的临界相，围绕之前已知的无能隙对称线。在这些新颖的相中，围绕动量q=π的自旋或轨道激发形成了无质量的连续体，这些连续体从SU(4)点属于[2^2]不可约表示的激发中分离出来。在临界对称线上，起源于[$2^11^2$]的围绕q=π/2的额外耦合自旋轨道激发也变得临界。
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English: We present analytical solutions to the nonlinear equations describing the
behavior of a gas of neutrinos with two flavors. Self-maintained coherent
flavor oscillations are shown to occur when the gas density exceeds a critical
value determined by the neutrino masses and the mean neutrino energy in the
gas. Similar oscillations may have occurred in the early Universe.
Chinese: 我们提出了描述具有两种味道的中微子气体行为的非线性方程的解析解。当气体密度超过由中微子质量和气体中中微子的平均能量确定的临界值时，显示出自维持的相干味道振荡会发生。在早期宇宙中可能已经发生了类似的振荡。
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English: Let ${\mathcal A}$ be the class of functions that are analytic in the unit
disc ${\mathbb D}$, normalized such that $f(z)=z+\sum_{n=2}^\infty a_nz^n$, and
let class ${\mathcal U}(\lambda)$, $0<\lambda\le1$, consists of functions
$f\in{\mathcal A}$, such that \[ \left |\left (\frac{z}{f(z)} \right
)^{2}f'(z)-1\right | < \lambda\quad (z\in {\mathbb D}). \] In this paper we
determine the sharp upper bounds for the Hankel determinants of second and
third order for the inverse functions of functions from the class ${\mathcal
U}(\lambda)$.
Chinese: 设 ${\mathcal A}$ 为在单位圆盘 ${\mathbb D}$ 上解析的函数类，归一化使得 $f(z)=z+\sum_{n=2}^\infty a_nz^n$，并设类 ${\mathcal U}(\lambda)$，其中 $0<\lambda\le1$，由属于 ${\mathcal A}$ 的函数 $f$ 组成，使得 \[ \left |\left (\frac{z}{f(z)} \right)^{2}f'(z)-1\right | < \lambda\quad (z\in {\mathbb D}). \] 在本文中，我们确定了来自类 ${\mathcal U}(\lambda)$ 的函数的逆函数的二阶和三阶 Hankel 矩阵的严格上界。
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English: Cultural activity is an inherent aspect of urban life and the success of a
modern city is largely determined by its capacity to offer generous cultural
entertainment to its citizens. To this end, the optimal allocation of cultural
establishments and related resources across urban regions becomes of vital
importance, as it can reduce financial costs in terms of planning and improve
quality of life in the city, more generally. In this paper, we make use of a
large longitudinal dataset of user location check-ins from the online social
network WeChat to develop a data-driven framework for cultural planning in the
city of Beijing. We exploit rich spatio-temporal representations on user
activity at cultural venues and use a novel extended version of the traditional
latent Dirichlet allocation model that incorporates temporal information to
identify latent patterns of urban cultural interactions. Using the
characteristic typologies of mobile user cultural activities emitted by the
model, we determine the levels of demand for different types of cultural
resources across urban areas. We then compare those with the corresponding
levels of supply as driven by the presence and spatial reach of cultural venues
in local areas to obtain high resolution maps that indicate urban regions with
lack of cultural resources, and thus give suggestions for further urban
cultural planning and investment optimisation.
Chinese: 文化活动是城市生活的一个固有方面，一个现代城市的成功在很大程度上取决于其向市民提供丰富文化娱乐的能力。为此，在城市区域内优化文化机构和相关资源的分配变得至关重要，因为它可以在规划方面降低财务成本，并在更广泛的意义上提高城市的生活质量。在本文中，我们利用来自在线社交网络微信的大量纵向用户位置签到数据集，为北京市的文化规划开发了一个数据驱动框架。我们利用用户在文化场所活动的丰富时空表示，并使用一种新型扩展的传统潜在狄利克雷分配模型，该模型结合了时间信息来识别城市文化互动的潜在模式。利用模型发出的移动用户文化活动的特征类型，我们确定城市不同区域对不同类型文化资源的需求水平。然后，我们将这些与由当地文化场所的存在和空间覆盖范围驱动的供应水平进行比较，以获得指示城市区域文化资源缺乏的高分辨率地图，从而为更进一步的 urban 文化规划和投资优化提供建议。
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English: In this Letter, we present a cosmic Bell experiment with
polarization-entangled photons, in which measurement settings were determined
based on real-time measurements of the wavelength of photons from high-redshift
quasars, whose light was emitted billions of years ago, the experiment
simultaneously ensures locality. Assuming fair sampling for all detected
photons and that the wavelength of the quasar photons had not been selectively
altered or previewed between emission and detection, we observe statistically
significant violation of Bell's inequality by $9.3$ standard deviations,
corresponding to an estimated $p$ value of $\lesssim 7.4 \times 10^{-21}$. This
experiment pushes back to at least $\sim 7.8$ Gyr ago the most recent time by
which any local-realist influences could have exploited the "freedom-of-choice"
loophole to engineer the observed Bell violation, excluding any such mechanism
from $96\%$ of the space-time volume of the past light cone of our experiment,
extending from the big bang to today.
Chinese: 在这封信中，我们提出了一项基于偏振纠缠光子的宇宙贝尔实验，其中测量设置是基于对高红移类星体发射的光子波长的实时测量确定的，这些光子的光是在数十亿年前发出的，实验同时确保了局域性。假设所有检测到的光子都进行了公平采样，并且类星体光子的波长在发射和探测之间没有被选择性地改变或预览，我们观察到贝尔不等式统计显著的违反，违反程度为$9.3$个标准偏差，这对应于一个估计的$p$值小于$7.4 \times 10^{-21}$。这项实验将最近任何局部现实主义影响能够利用“选择自由”漏洞来构造所观察到的贝尔违反的时间推回了至少$\sim 7.8$吉年前，排除了任何这样的机制占过去光锥中96%的时空体积，从大爆炸延伸至今。
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English: We investigate a recently developed approach [P. L. Silvestrelli, Phys. Rev.
Lett. 100, 053002 (2008); J. Phys. Chem. A 113, 5224 (2009)] that uses
maximally localized Wannier functions to evaluate the van der Waals
contribution to the total energy of a system calculated with density-functional
theory. We test it on a set of atomic and molecular dimers of increasing
complexity (argon, methane, ethene, benzene, phthalocyanine, and copper
phthalocyanine) and demonstrate that the method, as originally proposed, has a
number of shortcomings that hamper its predictive power. In order to overcome
these problems, we have developed and implemented a number of improvements to
the method and show that these modifications give rise to calculated binding
energies and equilibrium geometries that are in closer agreement to results of
quantum-chemical coupled-cluster calculations.
Chinese: 我们研究了一种最近发展的方法[P. L. Silvestrelli, 物理评论快报 100, 053002 (2008); 物理化学A 113, 5224 (2009)]，该方法使用最大局域化的Wannier函数来评估使用密度泛函理论计算的系统的范德华贡献到总能量。我们在一系列不断增加复杂性的原子和分子二聚体（氩、甲烷、乙烯、苯、酞菁和铜酞菁）上进行了测试，并证明该方法，正如最初提出的，存在一些缺点，这些缺点阻碍了其预测能力。为了克服这些问题，我们开发并实施了一系列对该方法的改进，并表明这些修改产生了与量子化学耦合簇计算结果更接近的绑定能和平衡几何形状。
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English: In the static analysis of functional programs, pushdown flow analysis and
abstract garbage collection push the boundaries of what we can learn about
programs statically. This work illuminates and poses solutions to theoretical
and practical challenges that stand in the way of combining the power of these
techniques. Pushdown flow analysis grants unbounded yet computable polyvariance
to the analysis of return-flow in higher-order programs. Abstract garbage
collection grants unbounded polyvariance to abstract addresses which become
unreachable between invocations of the abstract contexts in which they were
created. Pushdown analysis solves the problem of precisely analyzing recursion
in higher-order languages; abstract garbage collection is essential in solving
the "stickiness" problem. Alone, our benchmarks demonstrate that each method
can reduce analysis times and boost precision by orders of magnitude. We
combine these methods. The challenge in marrying these techniques is not
subtle: computing the reachable control states of a pushdown system relies on
limiting access during transition to the top of the stack; abstract garbage
collection, on the other hand, needs full access to the entire stack to compute
a root set, just as concrete collection does. Conditional pushdown systems were
developed for just such a conundrum, but existing methods are ill-suited for
the dynamic nature of garbage collection. We show fully precise and approximate
solutions to the feasible paths problem for pushdown garbage-collecting
control-flow analysis. Experiments reveal synergistic interplay between garbage
collection and pushdown techniques, and the fusion demonstrates
"better-than-both-worlds" precision.
Chinese: 在功能程序的静态分析中，下推流分析和抽象垃圾回收推动了我们可以从程序中静态学习的边界。这项工作阐明并提出了解决这些技术结合过程中所面临的理论和实践挑战的方案。下推流分析为高阶程序中的返回流分析赋予了无界的可计算多态性。抽象垃圾回收为在创建它们的抽象上下文中调用之间变得不可达的抽象地址赋予了无界的多态性。下推分析解决了精确分析高阶语言中递归的问题；抽象垃圾回收对于解决“粘性”问题至关重要。仅凭我们的基准测试，就可以证明每种方法都可以按数量级减少分析时间并提高精度。我们将这些方法结合起来。将这些技术结合起来的挑战并不微妙：计算下推系统的可达控制状态依赖于在过渡到栈顶时限制访问；另一方面，抽象垃圾回收需要访问整个栈以计算根集，就像具体收集一样。为了解决这样的难题，开发了条件下推系统，但现有方法不适合垃圾收集的动态特性。我们展示了针对下推垃圾回收控制流分析的可行路径问题的完全精确和近似解决方案。实验揭示了垃圾收集和下推技术之间的协同作用，并且融合证明了“优于两者”的精度。
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English: Microservices have gained wide recognition and acceptance in software
industries as an emerging architectural style for autonomic, scalable, and more
reliable computing. The transition to microservices has been highly motivated
by the need for better alignment of technical design decisions with improving
value potentials of architectures. Despite microservices' popularity, research
still lacks disciplined understanding of transition and consensus on the
principles and activities underlying "micro-ing" architectures. In this paper,
we report on a systematic mapping study that consolidates various views,
approaches and activities that commonly assist in the transition to
microservices. The study aims to provide a better understanding of the
transition; it also contributes a working definition of the transition and
technical activities underlying it. We term the transition and technical
activities leading to microservice architectures as microservitization. We then
shed light on a fundamental problem of microservitization: microservice
granularity and reasoning about its adaptation as first-class entities. This
study reviews state-of-the-art and -practice related to reasoning about
microservice granularity; it reviews modelling approaches, aspects considered,
guidelines and processes used to reason about microservice granularity. This
study identifies opportunities for future research and development related to
reasoning about microservice granularity.
Chinese: 微服务作为一种新兴的架构风格，因其自主、可扩展且更可靠的计算特性，已在软件产业中获得广泛认可和接受。转向微服务的主要动机源于技术设计决策与架构价值潜力之间更好对齐的需求。尽管微服务很受欢迎，但研究仍缺乏对过渡过程的系统性理解，以及对"微服务化"架构背后原则和活动的共识。在本文中，我们报告了一项系统性映射研究，该研究整合了各种有助于转向微服务的观点、方法和活动。该研究旨在提供对过渡过程的更好理解；同时贡献了该过渡过程及其技术活动的定义。我们将导致微服务架构的过渡和技术活动称为微服务化（microservitization）。然后，我们阐明了微服务化中的一个基本问题：微服务粒度及其作为一等实体的适应性推理。本研究回顾了与推理微服务粒度相关的最新研究成果和实践；它还回顾了用于推理微服务粒度的建模方法、考虑的方面、指南和流程。本研究确定了与推理微服务粒度相关的未来研究和发展机会。
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English: Let $\beta>1$ and let $m>\be$ be an integer. Each $x\in
I_\be:=[0,\frac{m-1}{\beta-1}]$ can be represented in the form \[
x=\sum_{k=1}^\infty \epsilon_k\beta^{-k}, \] where
$\epsilon_k\in\{0,1,...,m-1\}$ for all $k$ (a $\beta$-expansion of $x$). It is
known that a.e. $x\in I_\beta$ has a continuum of distinct $\beta$-expansions.
In this paper we prove that if $\beta$ is a Pisot number, then for a.e. $x$
this continuum has one and the same growth rate. We also link this rate to the
Lebesgue-generic local dimension for the Bernoulli convolution parametrized by
$\beta$.
When $\beta<\frac{1+\sqrt5}2$, we show that the set of $\beta$-expansions
grows exponentially for every internal $x$.
Chinese: 设 $\beta>1$ 且 $m>\beta$ 为一个整数。每个 $x\in I_\beta:=[0,\frac{m-1}{\beta-1}]$ 可以表示为以下形式 \[
x=\sum_{k=1}^\infty \epsilon_k\beta^{-k},
\]
其中 $\epsilon_k\in\{0,1,...,m-1\}$ 对所有 $k$ 都成立（$x$ 的 $\beta$-展开）。已知几乎处处 $x\in I_\beta$ 都有无限多个不同的 $\beta$-展开。在这篇论文中，我们证明如果 $\beta$ 是一个 Pisot 数，那么几乎处处 $x$ 的这个连续统具有相同的增长率。我们还将这个增长率与由 $\beta$ 参数化的伯努利卷积的 Lebesgue-通用局部维数联系起来。
当 $\beta<\frac{1+\sqrt5}2$ 时，我们证明对于每个内部点 $x$，$\beta$-展开的增长是指数级的。
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English: The choice of approximate posterior distributions plays a central role in
stochastic variational inference (SVI). One effective solution is the use of
normalizing flows \cut{defined on Euclidean spaces} to construct flexible
posterior distributions. However, one key limitation of existing normalizing
flows is that they are restricted to the Euclidean space and are ill-equipped
to model data with an underlying hierarchical structure. To address this
fundamental limitation, we present the first extension of normalizing flows to
hyperbolic spaces. We first elevate normalizing flows to hyperbolic spaces
using coupling transforms defined on the tangent bundle, termed Tangent
Coupling ($\mathcal{TC}$). We further introduce Wrapped Hyperboloid Coupling
($\mathcal{W}\mathbb{H}C$), a fully invertible and learnable transformation
that explicitly utilizes the geometric structure of hyperbolic spaces, allowing
for expressive posteriors while being efficient to sample from. We demonstrate
the efficacy of our novel normalizing flow over hyperbolic VAEs and Euclidean
normalizing flows. Our approach achieves improved performance on density
estimation, as well as reconstruction of real-world graph data, which exhibit a
hierarchical structure. Finally, we show that our approach can be used to power
a generative model over hierarchical data using hyperbolic latent variables.
Chinese: 在随机变分推理（SVI）中，近似后验分布的选择起着核心作用。一个有效的解决方案是使用在欧几里得空间上定义的正态化流来构建灵活的后验分布。然而，现有正态化流的一个关键局限性是它们被限制在欧几里得空间中，并且不擅长模拟具有潜在分层结构的数据。为了解决这一基本局限性，我们提出了将正态化流首次扩展到双曲空间。我们首先使用定义在切触丛上的耦合变换将正态化流提升到双曲空间，称为切触耦合（$\mathcal{TC}$）。我们进一步引入了包裹双曲抛物面耦合（$\mathcal{W}\mathbb{H}C$），这是一种完全可逆和可学习的变换，它明确利用了双曲空间的几何结构，允许构建具有表现力的后验分布，同时采样效率高。我们展示了我们的新颖正态化流在双曲变分自编码器（VAEs）和欧几里得正态化流上的有效性。我们的方法在密度估计以及具有分层结构的现实世界图数据的重建方面实现了改进的性能。最后，我们表明，我们的方法可以用作使用双曲潜在变量在分层数据上驱动生成模型。
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English: Dense kernel matrices resulting from pairwise evaluations of a kernel
function arise naturally in machine learning and statistics. Previous work in
constructing sparse approximate inverse Cholesky factors of such matrices by
minimizing Kullback-Leibler divergence recovers the Vecchia approximation for
Gaussian processes. These methods rely only on the geometry of the evaluation
points to construct the sparsity pattern. In this work, we instead construct
the sparsity pattern by leveraging a greedy selection algorithm that maximizes
mutual information with target points, conditional on all points previously
selected. For selecting $k$ points out of $N$, the naive time complexity is
$\mathcal{O}(N k^4)$, but by maintaining a partial Cholesky factor we reduce
this to $\mathcal{O}(N k^2)$. Furthermore, for multiple ($m$) targets we
achieve a time complexity of $\mathcal{O}(N k^2 + N m^2 + m^3)$, which is
maintained in the setting of aggregated Cholesky factorization where a selected
point need not condition every target. We apply the selection algorithm to
image classification and recovery of sparse Cholesky factors. By minimizing
Kullback-Leibler divergence, we apply the algorithm to Cholesky factorization,
Gaussian process regression, and preconditioning with the conjugate gradient,
improving over $k$-nearest neighbors selection.
Chinese: 由核函数对之间评价得到的稠密核矩阵在机器学习和统计学中自然产生。先前的通过最小化Kullback-Leibler散度来构造此类矩阵的稀疏近似逆Cholesky因子的工作恢复了Gaussian过程的Vecchia近似。这些方法仅依赖于评估点的几何来构造稀疏模式。在这项工作中，我们反而通过利用一个最大化与目标点之间条件于先前选择的所有点的互信息的贪心选择算法来构造稀疏模式。对于从$N$个点中选择$k$个点的选择，朴素的时间复杂度是$\mathcal{O}(N k^4)$，但通过维护部分Cholesky因子，我们将其减少到$\mathcal{O}(N k^2)$。此外，对于多个($m$)目标，我们实现了$\mathcal{O}(N k^2 + N m^2 + m^3)$的时间复杂度，这在聚合Cholesky因子的设置中保持不变，其中选择的点不必对每个目标进行条件判断。我们将选择算法应用于图像分类和稀疏Cholesky因子的恢复。通过最小化Kullback-Leibler散度，我们将算法应用于Cholesky因式分解、Gaussian过程回归以及使用共轭梯度法预处理，这比$k$最近邻选择有改进。
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English: We investigate the power of the Wang tile self-assembly model at temperature
1, a threshold value that permits attachment between any two tiles that share
even a single bond. When restricted to deterministic assembly in the plane, no
temperature 1 assembly system has been shown to build a shape with a tile
complexity smaller than the diameter of the shape. In contrast, we show that
temperature 1 self-assembly in 3 dimensions, even when growth is restricted to
at most 1 step into the third dimension, is capable of simulating a large class
of temperature 2 systems, in turn permitting the simulation of arbitrary Turing
machines and the assembly of $n\times n$ squares in near optimal $O(\log n)$
tile complexity. Further, we consider temperature 1 probabilistic assembly in
2D, and show that with a logarithmic scale up of tile complexity and shape
scale, the same general class of temperature $\tau=2$ systems can be simulated
with high probability, yielding Turing machine simulation and $O(\log^2 n)$
assembly of $n\times n$ squares with high probability. Our results show a sharp
contrast in achievable tile complexity at temperature 1 if either growth into
the third dimension or a small probability of error are permitted. Motivated by
applications in nanotechnology and molecular computing, and the plausibility of
implementing 3 dimensional self-assembly systems, our techniques may provide
the needed power of temperature 2 systems, while at the same time avoiding the
experimental challenges faced by those systems.
Chinese: 我们研究了王氏瓷砖自组装模型在温度1下的能力，这是一个允许任何两个共享单个键的瓷砖之间进行连接的阈值。当限制在平面上的确定性组装时，尚未证明存在温度1组装系统能够构建一个瓷砖复杂度小于形状直径的形状。相比之下，我们表明，即使在三维空间中的生长被限制为最多向第三维度扩展一步，温度1的三维自组装仍然能够模拟一大类温度2系统，进而允许模拟任意图灵机以及在接近最优的O(log n)瓷砖复杂度下组装n×n的正方形。此外，我们考虑了二维空间中的温度1概率性组装，并表明在瓷砖复杂度和形状规模上进行对数规模放大后，相同的温度τ=2系统的一般类别可以在高概率下被模拟，从而实现图灵机模拟和高概率下O(log^2 n)的n×n正方形组装。我们的结果表明，如果允许向第三维度生长或存在小的错误概率，温度1下可实现的瓷砖复杂度将形成鲜明对比。受纳米技术和分子计算应用以及实现三维自组装系统的可能性所启发，我们的技术可能在同时避免那些系统面临实验挑战的情况下，提供所需温度2系统的能力。
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English: Spatial Crowdsourcing (SC) is a novel platform that engages individuals in
the act of collecting various types of spatial data. This method of data
collection can significantly reduce cost and turnover time, and is particularly
useful in urban environmental sensing, where traditional means fail to provide
fine-grained field data. In this study, we introduce hyperlocal spatial
crowdsourcing, where all workers who are located within the spatiotemporal
vicinity of a task are eligible to perform the task, e.g., reporting the
precipitation level at their area and time. In this setting, there is often a
budget constraint, either for every time period or for the entire campaign, on
the number of workers to activate to perform tasks. The challenge is thus to
maximize the number of assigned tasks under the budget constraint, despite the
dynamic arrivals of workers and tasks. We introduce a taxonomy of several
problem variants, such as budget-per-time-period vs. budget-per-campaign and
binary-utility vs. distance-based-utility. We study the hardness of the task
assignment problem in the offline setting and propose online heuristics which
exploits the spatial and temporal knowledge acquired over time. Our experiments
are conducted with spatial crowdsourcing workloads generated by the SCAWG tool
and extensive results show the effectiveness and efficiency of our proposed
solutions.
Chinese: 空间众包（SC）是一个新型平台，它让个人参与到收集各种类型空间数据的行为中。这种数据收集方法可以显著降低成本和周转时间，并在城市环境感知方面特别有用，因为传统的手段无法提供细粒度的现场数据。在本研究中，我们介绍了超本地空间众包，其中所有位于任务时空邻近区域的工作者都有资格执行任务，例如报告他们所在地区和时间段的降水量。在这种设置中，通常对激活以执行任务的工人数量存在预算限制，无论是针对每个时间段还是整个活动。因此，挑战在于在预算限制下最大化分配的任务数量，尽管工人和任务的动态到达。我们介绍了几种问题变体的分类，例如按时间段预算与按活动预算，以及二元效用与基于距离的效用。我们研究了离线设置中任务分配问题的难度，并提出了在线启发式算法，该算法利用了随着时间的推移获得的空间和时间知识。我们的实验使用由SCAWG工具生成的空间众包工作负载进行，广泛的结果显示了我们所提解决方案的有效性和效率。
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English: In this paper, we present an analytical model for a diffusive molecular
communication (MC) system with a reversible adsorption receiver in a fluid
environment. The time-varying spatial distribution of the information molecules
under the reversible adsorption and desorption reaction at the surface of a
bio-receiver is analytically characterized. Based on the spatial distribution,
we derive the number of newly-adsorbed information molecules expected in any
time duration. Importantly, we present a simulation framework for the proposed
model that accounts for the diffusion and reversible reaction. Simulation
results show the accuracy of our derived expressions, and demonstrate the
positive effect of the adsorption rate and the negative effect of the
desorption rate on the net number of newly-adsorbed information molecules
expected. Moreover, our analytical results simplify to the special case of an
absorbing receiver.
Chinese: 在本文中，我们针对流体环境中具有可逆吸附接收器的扩散分子通信（MC）系统，建立了一个分析模型。通过解析方法，我们描述了生物接收器表面可逆吸附和解吸反应下信息分子的时变空间分布。基于该空间分布，我们推导出任意时间间隔内预期吸附的新信息分子数量。重要的是，我们提出了一个考虑扩散和可逆反应的模型仿真框架。仿真结果验证了我们推导公式的准确性，并表明吸附速率对预期新吸附信息分子净数量的正向影响，以及解吸速率的负向影响。此外，我们的解析结果可简化为吸收接收器的特殊情况。
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English: We develop a new approach to study the nonlinear evolution in the large-scale
structure of the Universe both in real space and in redshift space, extending
the standard perturbation theory of gravitational instability. Infinite series
of terms in standard Eulerian perturbation theory are resummed as a result of
our starting from a Lagrangian description of perturbations. Delicate nonlinear
effects on scales of the baryon acoustic oscillations are more accurately
described by our method than the standard one. Our approach differs from other
resummation techniques recently proposed, such as the renormalized perturbation
theory, etc., in that we use simple techniques and thus resulting equations are
undemanding to evaluate, and in that our approach is capable of quantifying the
nonlinear effects in redshift space. The power spectrum and correlation
function of our approach are in good agreement with numerical simulations in
literature on scales of baryon acoustic oscillations. Especially, nonlinear
effects on the baryon acoustic peak of the correlation function are accurately
described both in real space and in redshift space. Our approach provides a
unique opportunity to analytically investigate the nonlinear effects on baryon
acoustic scales in observable redshift space, which is requisite in
constraining the nature of dark energy, the curvature of the Universe, etc., by
redshift surveys.
Chinese: 我们开发了一种新方法，用于研究宇宙大尺度结构中的非线性演化，该方法同时适用于真实空间和红移空间，并扩展了重力不稳定性标准的扰动理论。由于我们从扰动的拉格朗日描述出发，标准欧拉扰动理论中的无限级数项被求和。与标准方法相比，我们的方法能更精确地描述巴丰声振荡尺度上的微妙非线性效应。我们的方法与近期提出的其他求和技巧（如重整化扰动理论等）不同，原因在于我们使用了简单技术，因此所得方程易于求解，并且我们的方法能够量化红移空间中的非线性效应。我们的方法的功率谱和相关函数与文献中关于巴丰声振荡尺度的数值模拟结果吻合良好。特别是，相关函数的巴丰声峰在真实空间和红移空间中的非线性效应都得到了精确描述。我们的方法为分析研究可观测红移空间中巴丰声尺度上的非线性效应提供了一个独特的机会，这对于通过红移巡天观测来约束暗能量的本质、宇宙曲率等至关重要。
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English: This paper investigates the efficient solution of penalized quadratic
regressions in high-dimensional settings. A novel and efficient algorithm for
ridge-penalized quadratic regression is proposed, leveraging the matrix
structures of the regression with interactions. Additionally, an alternating
direction method of multipliers (ADMM) framework is developed for penalized
quadratic regression with general penalties, including both single and hybrid
penalty functions. The approach simplifies the calculations to basic
matrix-based operations, making it appealing in terms of both memory storage
and computational complexity for solving penalized quadratic regressions in
high-dimensional settings.
Chinese: 本文研究了高维场景下惩罚二次回归的高效求解方法。提出了一个新颖高效的岭惩罚二次回归算法，利用了带交互的回归矩阵结构。此外，还开发了适用于带通用惩罚的惩罚二次回归的乘子交替方向法（ADMM）框架，包括单一惩罚函数和混合惩罚函数。该方法将计算简化为基本的基于矩阵的操作，在高维场景下求解惩罚二次回归时，在内存存储和计算复杂度方面都具有吸引力。
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English: The proliferation of phishing sites and emails poses significant challenges
to existing cybersecurity efforts. Despite advances in malicious email filters
and email security protocols, problems with oversight and false positives
persist. Users often struggle to understand why emails are flagged as
potentially fraudulent, risking the possibility of missing important
communications or mistakenly trusting deceptive phishing emails. This study
introduces ChatSpamDetector, a system that uses large language models (LLMs) to
detect phishing emails. By converting email data into a prompt suitable for LLM
analysis, the system provides a highly accurate determination of whether an
email is phishing or not. Importantly, it offers detailed reasoning for its
phishing determinations, assisting users in making informed decisions about how
to handle suspicious emails. We conducted an evaluation using a comprehensive
phishing email dataset and compared our system to several LLMs and baseline
systems. We confirmed that our system using GPT-4 has superior detection
capabilities with an accuracy of 99.70%. Advanced contextual interpretation by
LLMs enables the identification of various phishing tactics and impersonations,
making them a potentially powerful tool in the fight against email-based
phishing threats.
Chinese: 钓鱼网站和邮件的泛滥给现有的网络安全工作带来了重大挑战。尽管恶意邮件过滤器和邮件安全协议取得了进步，但监管不足和假阳性问题仍然存在。用户常常难以理解为什么邮件会被标记为可能欺诈，这可能导致错过重要通信或错误地信任欺骗性钓鱼邮件。本研究介绍了ChatSpamDetector系统，该系统使用大型语言模型（LLMs）检测钓鱼邮件。通过将邮件数据转换为适合LLM分析的提示，该系统能够高度准确地判断邮件是否为钓鱼邮件。重要的是，它为钓鱼判断提供详细理由，帮助用户就如何处理可疑邮件做出明智决策。我们使用全面的钓鱼邮件数据集进行了评估，并将我们的系统与多个LLMs和基线系统进行了比较。我们确认使用GPT-4的系统具有卓越的检测能力，准确率达到99.70%。LLMs的先进上下文解释能力能够识别各种钓鱼策略和冒充行为，使其成为对抗基于邮件的钓鱼威胁的潜在有力工具。
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English: The personalization of our news consumption on social media has a tendency to
reinforce our pre-existing beliefs instead of balancing our opinions. This
finding is a concern for the health of our democracies which rely on an access
to information providing diverse viewpoints. To tackle this issue from a
computational perspective, Garimella et al. (NIPS'17) modeled the spread of
these viewpoints, also called campaigns, using the well-known independent
cascade model and studied an optimization problem that aims at balancing
information exposure in a social network when two opposing campaigns propagate
in the network. The objective in their $NP$-hard optimization problem is to
maximize the number of people that are exposed to either both or none of the
viewpoints. For two different settings, one corresponding to a model where
campaigns spread in a correlated manner, and a second one, where the two
campaigns spread in a heterogeneous manner, they provide constant ratio
approximation algorithms. In this paper, we investigate a more general
formulation of this problem. That is, we assume that $\mu$ different campaigns
propagate in a social network and we aim to maximize the number of people that
are exposed to either $\nu$ or none of the campaigns, where $\mu\ge\nu\ge2$. We
provide dedicated approximation algorithms for both the correlated and
heterogeneous settings. Interestingly, for the heterogeneous setting with
$\nu\ge 3$, we give a reduction leading to several approximation hardness
results. Maybe most importantly, we obtain that the problem cannot be
approximated within a factor of $n^{-g(n)}$ for any $g(n)=o(1)$ assuming
Gap-ETH, denoting with $n$ the number of nodes in the social network. For $\nu
\ge 4$, there is no $n^{-\epsilon}$-approximation algorithm if a certain class
of one-way functions exists, where $\epsilon > 0$ is a given constant which
depends on $\nu$.
Chinese: 我们在社交媒体上个性化新闻消费的趋势有强化我们既有的信念而非平衡我们观点的倾向。这一发现对我们民主制度的健全构成担忧，这些制度依赖于提供多样观点的信息获取途径。为了从计算角度解决这个问题，Garimella 等人（NIPS'17）使用著名的独立级联模型来模拟这些观点的传播，也被称为运动，并研究了一个优化问题，该问题旨在平衡社交网络中当两个对立的竞选活动在网络中传播时的信息曝光。他们 $NP$ 难优化问题的目标是最大化被暴露于两种观点中至少一种或两种观点都没有的人数。对于两种不同的情况，一种对应于竞选活动以相关方式传播的模型，另一种对应于两种竞选活动以异质方式传播的模型，他们提供了常数比率近似算法。在这篇论文中，我们研究了这个问题的更一般形式。也就是说，我们假设 $\mu$ 个不同的竞选活动在社交网络中传播，我们旨在最大化被暴露于 $\nu$ 个或两种竞选活动都没有的人数，其中 $\mu \geq \nu \geq 2$。我们为两种相关和异质情况提供了专门的近似算法。有趣的是，对于 $\nu \geq 3$ 的异质情况，我们给出了一种导致多个近似困难结果的归约。也许最重要的是，我们得到了一个问题不能在 $n^{-g(n)}$ 因子内被近似，其中 $g(n)=o(1)$，假设 Gap-ETH，用 $n$ 表示社交网络中节点的数量。对于 $\nu \geq 4$，如果存在一类单向函数，则不存在 $n^{-\epsilon}$ 近似算法，其中 $\epsilon > 0$ 是一个依赖于 $\nu$ 的给定常数。
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English: We consider the effect of inhomogeneities on the expansion of the Einstein-de
Sitter universe. We find that the backreaction of linear scalar metric
perturbations results in apparent dark energy with a mixture of equations of
state between 0 and -4/3. We discuss the possibility that backreaction could
account for present-day acceleration.
Chinese: 我们考虑了不均匀性对爱因斯坦-德西特宇宙膨胀的影响。我们发现，线性标量度规扰动的反作用导致出现具有介于0和-4/3之间状态方程混合的暗能量。我们讨论了反作用可能解释当今宇宙加速膨胀的可能性。
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English: Randomized smoothing is a leading approach for constructing classifiers that
are certifiably robust against adversarial examples. Existing work on
randomized smoothing has focused on classifiers with continuous inputs, such as
images, where $\ell_p$-norm bounded adversaries are commonly studied. However,
there has been limited work for classifiers with discrete or variable-size
inputs, such as for source code, which require different threat models and
smoothing mechanisms. In this work, we adapt randomized smoothing for discrete
sequence classifiers to provide certified robustness against edit
distance-bounded adversaries. Our proposed smoothing mechanism randomized
deletion (RS-Del) applies random deletion edits, which are (perhaps
surprisingly) sufficient to confer robustness against adversarial deletion,
insertion and substitution edits. Our proof of certification deviates from the
established Neyman-Pearson approach, which is intractable in our setting, and
is instead organized around longest common subsequences. We present a case
study on malware detection--a binary classification problem on byte sequences
where classifier evasion is a well-established threat model. When applied to
the popular MalConv malware detection model, our smoothing mechanism RS-Del
achieves a certified accuracy of 91% at an edit distance radius of 128 bytes.
Chinese: 随机平滑是一种构建对对抗样本具有可证明鲁棒性的分类器的领先方法。现有关于随机平滑的研究主要集中于具有连续输入的分类器，例如图像，其中通常研究 L_p 范数有界的对抗样本。然而，对于具有离散或可变大小输入的分类器（例如源代码），由于需要不同的威胁模型和平滑机制，相关研究有限。在本工作中，我们将随机平滑应用于离散序列分类器，以提供对编辑距离有界对抗样本的可证明鲁棒性。我们提出的平滑机制随机删除（RS-Del）应用随机删除编辑，出乎意料的是，这些操作足以使分类器对对抗删除、插入和替换编辑具有鲁棒性。我们的认证证明偏离了既定的奈曼-皮尔逊方法（该方法在我们的场景下难以处理），而是围绕最长公共子序列构建。我们对恶意软件检测进行了案例研究——这是一个关于字节序列的二分类问题，其中分类器规避是一个已确立的威胁模型。当应用于流行的 MalConv 恶意软件检测模型时，我们的平滑机制 RS-Del 在编辑距离半径为 128 字节时，实现了 91% 的可证明准确率。
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English: The recently reported \textit{A}V$_3$Sb$_5$ (\textit{A} = K, Rb, Cs) family
of kagome metals are candidates for unconventional superconductivity and chiral
charge density wave (CDW) order; both potentially arise from nested saddle
points in their band structures close to the Fermi energy. Here we use chemical
substitution to introduce holes into CsV$_3$Sb$_{5}$ and unveil an
unconventionalcoupling of the CDW and superconducting states. Specifically, we
generate a phase diagram for CsV$_3$Sb$_{5-x}$Sn$_{x}$ that illustrates the
impact of hole-doping the system and lifting the nearest vHs toward and above
$E_F$. Superconductivity exhibits a non-monotonic evolution with the
introduction of holes, resulting in two "domes" peaked at 3.6\,K and 4.1\,K and
the rapid suppression of three-dimensional CDW order. The evolution of CDW and
superconducting order is compared with the evolution of the electronic band
structure of CsV$_3$Sb$_{5-x}$Sn$_x$, where the complete suppression of
superconductivity seemingly coincides with an electron-like band comprised of
Sb $p_z$ orbitals pushed above E$_F$.
Chinese: 最近报道的 \textit{A}V$_3$Sb$_5$ (\textit{A} = K, Rb, Cs) 家族是具有非常规超导性和手性电荷密度波（CDW）序的候选材料；这两种性质都可能源于其能带结构在费米能附近嵌套鞍点的产生。在这里，我们通过化学替换在 CsV$_3$Sb$_{5}$ 中引入空穴，并揭示 CDW 和超导态之间的非常规耦合。具体来说，我们为 CsV$_3$Sb$_{5-x}$Sn$_{x}$ 生成了一个相图，该图说明了空穴掺杂对系统的影响以及将最近邻 vHs 提升至和超过 $E_F$。随着空穴的引入，超导性表现出非单调演化，导致在 3.6\,K 和 4.1\,K 处出现两个“穹顶”，并且三维 CDW 序列迅速被抑制。CDW 和超导序的演化与 CsV$_3$Sb$_{5-x}$Sn$_x$ 的电子能带结构演化进行了比较，其中超导性的完全抑制似乎与一个由 Sb $p_z$ 轨道组成、被推至 E$_F$ 以上的电子能带相一致。
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English: We carry out a large-scale empirical data analysis to examine the efficiency
of the so-called pairs trading. On the basis of relevant three thresholds,
namely, starting, profit-taking, and stop-loss for the `first-passage process'
of the spread (gap) between two highly-correlated stocks, we construct an
effective strategy to make a trade via `active' stock-pairs automatically. The
algorithm is applied to $1,784$ stocks listed on the first section of the Tokyo
Stock Exchange leading up to totally $1,590,436$ pairs. We are numerically
confirmed that the asset management by means of the pairs trading works
effectively at least for the past three years (2010-2012) data sets in the
sense that the profit rate becomes positive (totally positive arbitrage) in
most cases of the possible combinations of thresholds corresponding to
`absorbing boundaries' in the literature of first-passage processes.
Chinese: 我们进行了一次大规模的实证数据分析，以检验所谓的对冲交易效率。基于相关的三个阈值，即起始点、盈利点和止损点，针对两个高度相关股票之间的价差（差距）的“首次通过过程”，我们构建了一种有效的策略，通过“主动”的股票对自动进行交易。该算法应用于东京证券交易所第一板块的1,784只股票，总共形成了1,590,436对。我们通过数值分析确认，通过对冲交易进行资产管理至少在过去三年（2010-2012）的数据集中是有效的，即在文献中对应于“吸收边界”的阈值可能组合的大多数情况下，收益率变为正值（完全正值套利）。
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English: Pre-training over mixtured multi-task, multi-domain, and multi-modal data
remains an open challenge in vision perception pre-training. In this paper, we
propose GPPF, a General Perception Pre-training Framework, that pre-trains a
task-level dynamic network, which is composed by knowledge "legos" in each
layers, on labeled multi-task and multi-domain datasets. By inspecting humans'
innate ability to learn in complex environment, we recognize and transfer three
critical elements to deep networks: (1) simultaneous exposure to diverse
cross-task and cross-domain information in each batch. (2) partitioned
knowledge storage in separate lego units driven by knowledge sharing. (3)
sparse activation of a subset of lego units for both pre-training and
downstream tasks. Noteworthy, the joint training of disparate vision tasks is
non-trivial due to their differences in input shapes, loss functions, output
formats, data distributions, etc. Therefore, we innovatively develop a
plug-and-play multi-task training algorithm, which supports Single Iteration
Multiple Tasks (SIMT) concurrently training. SIMT lays the foundation of
pre-training with large-scale multi-task multi-domain datasets and is proved
essential for stable training in our GPPF experiments. Excitingly, the
exhaustive experiments show that, our GPPF-R50 model achieves significant
improvements of 2.5-5.8 over a strong baseline of the 8 pre-training tasks in
GPPF-15M and harvests a range of SOTAs over the 22 downstream tasks with
similar computation budgets. We also validate the generalization ability of
GPPF to SOTA vision transformers with consistent improvements. These solid
experimental results fully prove the effective knowledge learning, storing,
sharing, and transfer provided by our novel GPPF framework.
Chinese: 在视觉感知预训练中，在混合多任务、多领域和多模态数据上进行预训练仍然是一个开放性的挑战。在本文中，我们提出了GPPF，一个通用感知预训练框架，该框架预训练一个任务级别的动态网络，该网络由每层中的知识“乐高积木”组成，并在标记的多任务和多领域数据集上进行预训练。通过观察人类在复杂环境中学习的本能能力，我们识别并转移了三个关键元素到深度网络中：(1) 每批同时接触多样化的跨任务和跨领域信息。(2) 由知识共享驱动的知识在独立的乐高单元中分区存储。(3) 针对预训练和下游任务，部分乐高单元的稀疏激活。值得注意的是，由于不同视觉任务在输入形状、损失函数、输出格式、数据分布等方面的差异，异构视觉任务的联合训练非同小可。因此，我们创新性地开发了一种即插即用的多任务训练算法，该算法支持单次迭代多任务（SIMT）的并发训练。SIMT为使用大规模多任务多领域数据集的预训练奠定了基础，并在我们的GPPF实验中证明对于稳定训练至关重要。令人兴奋的是，全面实验表明，我们的GPPF-R50模型在GPPF-15M的8个预训练任务的基础上实现了2.5-5.8的显著改进，并在具有相似计算预算的22个下游任务中取得了各种SOTA（最先进的技术）成果。我们还验证了GPPF对SOTA视觉变换器的泛化能力，并取得了持续改进。这些坚实的实验结果充分证明了我们新颖的GPPF框架提供的有效知识学习、存储、共享和转移。
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English: In this note, we consider special algebraic cycles on the Shimura variety S
associated to a quadratic space V over a totally real field F, |F:\Q|=d, of
signature ((m,2)^{d_+},(m+2,0)^{d-d_+}), 1\le d_+<d. For each n, 1\le n\le m,
there are special cycles Z(T) in S, of codimension nd_+, indexed by totally
positive semi-definite matrices with coefficients in the ring of integers O_F.
The generating series for the classes of these cycles in the cohomology group
H^{2nd_+}(S) are Hilbert-Siegel modular forms of parallel weight m/2+1. One can
form analogous generating series for the classes of the special cycles in the
Chow group CH^{nd_+}(S). For d_+=1 and n=1, the modularity of these series was
proved by Yuan-Zhang-Zhang. In this note we prove the following: Assume the
Bloch-Beilinson conjecture on the injectivity of Abel-Jacobi maps. Then the
Chow group valued generating series for special cycles of codimension nd_+ on S
is modular for all n with 1\le n\le m.
Chinese: 在这篇笔记中，我们考虑与一个定义在完全实数域F上的二次空间V相关的Shimura簇S上的特殊代数循环，其中|F:\Q|=d，F的signature为((m,2)^{d_+},(m+2,0)^{d-d_+})，1\le d_+<d。对于每个n，1\le n\le m，S中存在特殊循环Z(T)，其维数为nd_+，由系数在整数环O_F中的全正半定矩阵索引。这些循环在同调群H^{2nd_+}(S)中的生成级数是平行权重为m/2+1的Hilbert-Siegel模形式。可以形成类似生成级数，用于Chow群CH^{nd_+}(S)中特殊循环的类。对于d_+=1和n=1，这些级数的模性已被袁-张-张证明。在这篇笔记中，我们证明以下内容：假设对阿贝尔-雅可比映射的注入性成立Bloch-Beilinson猜想。那么，S上维数为nd_+的特殊循环的Chow群值生成级数对于所有1\le n\le m的n都是模的。
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English: We study polynomial-time approximation algorithms for two closely-related
problems, namely computing shortcuts and transitive-closure spanners (TC
spanner). For a directed unweighted graph $G=(V, E)$ and an integer $d$, a set
of edges $E'\subseteq V\times V$ is called a $d$-TC spanner of $G$ if the graph
$H:=(V, E')$ has (i) the same transitive-closure as $G$ and (ii) diameter at
most $d.$ The set $E''\subseteq V\times V$ is a $d$-shortcut of $G$ if $E\cup
E''$ is a $d$-TC spanner of $G$. Our focus is on the following $(\alpha_D,
\alpha_S)$-approximation algorithm: given a directed graph $G$ and integers $d$
and $s$ such that $G$ admits a $d$-shortcut (respectively $d$-TC spanner) of
size $s$, find a $(d\alpha_D)$-shortcut (resp. $(d\alpha_D)$-TC spanner) with
$s\alpha_S$ edges, for as small $\alpha_S$ and $\alpha_D$ as possible.
As our main result, we show that, under the Projection Game Conjecture (PGC),
there exists a small constant $\epsilon>0$, such that no polynomial-time
$(n^{\epsilon},n^{\epsilon})$-approximation algorithm exists for finding
$d$-shortcuts as well as $d$-TC spanners of size $s$. Previously,
super-constant lower bounds were known only for $d$-TC spanners with constant
$d$ and ${\alpha_D}=1$ [Bhattacharyya, Grigorescu, Jung, Raskhodnikova,
Woodruff 2009]. Similar lower bounds for super-constant $d$ were previously
known only for a more general case of directed spanners [Elkin, Peleg 2000]. No
hardness of approximation result was known for shortcuts prior to our result.
As a side contribution, we complement the above with an upper bound of the
form $(n^{\gamma_D}, n^{\gamma_S})$-approximation which holds for $3\gamma_D +
2\gamma_S > 1$ (e.g., $(n^{1/5+o(1)}, n^{1/5+o(1)})$-approximation).
Chinese: 我们研究两个密切相关的问题——计算捷径和传递闭包跨度器（TC跨度器）的多项式时间近似算法。对于有向无权图 $G=(V, E)$ 和整数 $d$，如果边集 $E'\subseteq V\times V$ 满足图 $H:=(V, E')$ 具有性质 (i) 与 $G$ 相同的传递闭包和 (ii) 最大直径不超过 $d$，则称 $E'$ 是 $G$ 的一个 $d$-TC 跨度器。如果 $E\cup E''$ 是 $G$ 的一个 $d$-TC 跨度器，则边集 $E''\subseteq V\times V$ 是 $G$ 的一个 $d$-捷径。我们的关注点在于以下 $(\alpha_D, \alpha_S)$-近似算法：给定一个有向图 $G$ 和整数 $d$、$s$，其中 $G$ 存在大小为 $s$ 的 $d$-捷径（或 $d$-TC 跨度器），寻找一个包含 $s\alpha_S$ 条边的 $(d\alpha_D)$-捷径（或 $(d\alpha_D)$-TC 跨度器），使得 $\alpha_S$ 和 $\alpha_D$ 尽可能小。作为我们的主要结果，我们在投影博弈猜想（PGC）下证明，存在一个小的常数 $\epsilon>0$，使得不存在多项式时间 $(n^{\epsilon},n^{\epsilon})$-近似算法来寻找大小为 $s$ 的 $d$-捷径和 $d$-TC 跨度器。此前，仅已知对于常数 $d$ 和 ${\alpha_D}=1$ 的 $d$-TC 跨度器存在超常数下界 [Bhattacharyya, Grigorescu, Jung, Raskhodnikova, Woodruff 2009]。对于超常数 $d$ 的类似下界此前仅对更一般的有向跨度器情况已知 [Elkin, Peleg 2000]。在我们结果之前，对于捷径尚无近似硬性结果。作为附带贡献，我们补充了一个形式为 $(n^{\gamma_D}, n^{\gamma_S})$-近似的上界，该上界在 $3\gamma_D + 2\gamma_S > 1$ 时成立（例如 $(n^{1/5+o(1)}, n^{1/5+o(1)})$-近似）。
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English: We study the non-perturbative superpotential generated by D(-1)-branes in
type IIB compactifications on orientifolds of Calabi-Yau threefold
hypersurfaces. To compute the D-instanton superpotential, we study F-theory
compactification on toric complete intersection elliptic Calabi-Yau fourfolds.
We take the Sen-limit, but with finite $g_s,$ in F-theory compactification with
a restriction that all D7-branes are carrying SO(8) gauge groups, which we call
the global Sen-limit. In the global Sen-limit, the axio-dilaton is not varying
in the compactification manifold. We compute the Picard-Fuchs equations of
elliptic Calabi-Yau fourfolds in the global Sen-limit, and show that the
Picard-Fuchs equations of the elliptic fourfolds split into that of the
underlying Calabi-Yau threefolds and of the elliptic fiber. We then demonstrate
that this splitting property of the Picard-Fuchs equation implies that the
fourform period of the elliptic Calabi-Yau fourfolds in the global Sen-limit
does not contain exponentially suppressed terms $\mathcal{O}(e^{-\pi/g_s})$.
With this result, we finally show that in the global Sen-limit, the
superpotential of the underlying type IIB compactification does not receive
D(-1)-instanton contributions. This result is exact in $g_s.$
Chinese: 我们研究了在卡里-尤三维超曲面导向折叠上的IIB紧化中由D(-1)膜产生的非微扰超势。为了计算D-instanton超势，我们研究了F理论在托里克完备交椭圆卡里-尤四维紧化上的应用。我们采用Sen极限，但在F理论紧化中，所有D7膜都携带SO(8)规范群，我们称之为全局Sen极限。在全局Sen极限中，轴向-稀释子场在紧化流形中不变化。我们在全局Sen极限下计算了椭圆卡里-尤四维的Picard-Fuchs方程，并表明椭圆四维的Picard-Fuchs方程分解为底层的卡里-尤三维超曲面和椭圆纤维的方程。然后我们证明这种Picard-Fuchs方程的分解性质意味着在全局Sen极限下，椭圆卡里-尤四维的四形式周期不包含指数衰减项$\mathcal{O}(e^{-\pi/g_s})$。有了这个结果，我们最终证明在全局Sen极限下，底层IIB紧化的超势不接收D(-1)-instanton的贡献。这个结果在$g_s$下是精确的。
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English: It is known that standard stochastic Galerkin methods encounter challenges
when solving partial differential equations with high-dimensional random
inputs, which are typically caused by the large number of stochastic basis
functions required. It becomes crucial to properly choose effective basis
functions, such that the dimension of the stochastic approximation space can be
reduced. In this work, we focus on the stochastic Galerkin approximation
associated with generalized polynomial chaos (gPC), and explore the gPC
expansion based on the analysis of variance (ANOVA) decomposition. A concise
form of the gPC expansion is presented for each component function of the ANOVA
expansion, and an adaptive ANOVA procedure is proposed to construct the overall
stochastic Galerkin system. Numerical results demonstrate the efficiency of our
proposed adaptive ANOVA stochastic Galerkin method for both diffusion and
Helmholtz problems.
Chinese: 众所周知，标准随机伽辽金方法在解决具有高维随机输入的偏微分方程时面临挑战，这些挑战通常由所需的大量随机基函数引起。因此，正确选择有效的基函数变得至关重要，这样可以降低随机逼近空间的维度。在本工作中，我们专注于与广义多项式混沌（gPC）相关的随机伽辽金近似，并基于方差分析（ANOVA）分解来探索gPC展开。我们为ANOVA展开的每个分量函数提供了一个简明的gPC展开形式，并提出了一种自适应ANOVA程序来构建整体随机伽辽金系统。数值结果表明，我们提出的自适应ANOVA随机伽辽金方法对于扩散问题和亥姆霍兹问题都表现出效率。
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English: The superconducting transition is studied within the one-loop renormalization
group in fixed dimension $D=3$ and at the critical point. A tricritical
behavior is found, and for $\kappa > \kappa_c$, an attractive charged fixed
point, distinct from that of a neutral superfluid. The critical exponents of
the continuous transition are evaluated, and it is shown that the anomalous
dimension of the gauge field equals unity. This implies the proportionality of
the magnetic field penetration depth and the superconducting correlation length
below the transition. The penetration depth exponent is nonclassical. We argue
that it can not be extracted from the dual theory in a straightforward manner
since it is not renormalized by fluctuations of the dual field.
Chinese: 在一维固定为$D=3$的框架内，使用一环重整化群研究超导转变。在临界点，发现了一种三临界行为，且当$\kappa > \kappa_c$时，存在一个吸引性的带电固定点，这与中性超流体的固定点不同。对连续转变的临界指数进行了评估，并证明规范场的异常维度等于1。这表明在转变以下，磁场的穿透深度与超导关联长度成正比。穿透深度指数是非经典的。我们认为，它不能直接从对偶理论中提取出来，因为它不是由对偶场的涨落所重整化的。
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