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English: Density dependent families of Markov chains, such as the stochastic models of
mass-action chemical kinetics, converge for large values of the indexing
parameter $N$ to deterministic systems of differential equations (Kurtz, 1970).
Moreover for moderate $N$ they can be strongly approximated by paths of a
diffusion process (Kurtz, 1976). Such an approximation however fails if the
state space is bounded (at zero or at a constant maximum level due to
conservation of mass) and if the process visits the boundaries with non
negligible probability. We present a strong approximation by a jump-diffusion
process which is robust to this event. The result is illustrated with a
particularly hard case study.
Chinese: 密度依赖的马尔可夫链族，例如质量作用化学动力学的随机模型，在索引参数 $N$ 的值很大时收敛到确定性微分方程系统（Kurtz，1970）。此外，对于中等的 $N$ 值，它们可以通过扩散过程的路径进行强烈近似（Kurtz，1976）。然而，如果状态空间是有界的（由于质量守恒在零或一个恒定的最大水平），并且过程以非忽略不计的概率访问边界时，这种近似将失败。我们提出了一种通过跳-扩散过程进行强烈近似的方法，该方法对这一事件具有鲁棒性。结果通过一个特别困难的案例研究进行了说明。
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English: Data and algorithms have the potential to produce and perpetuate
discrimination and disparate treatment. As such, significant effort has been
invested in developing approaches to defining, detecting, and eliminating
unfair outcomes in algorithms. In this paper, we focus on performing
statistical inference for fairness. Prior work in fairness inference has
largely focused on inferring the fairness properties of a given predictive
algorithm. Here, we expand fairness inference by evaluating fairness in the
data generating process itself, referred to here as data fairness. We perform
inference on data fairness using targeted learning, a flexible framework for
nonparametric inference. We derive estimators demographic parity, equal
opportunity, and conditional mutual information. Additionally, we find that our
estimators for probabilistic metrics exploit double robustness. To validate our
approach, we perform several simulations and apply our estimators to real data.
Chinese: 数据和算法具有产生和持续歧视及差别待遇的潜力。因此，人们投入了大量精力来开发定义、检测和消除算法中不公平结果的方法。在本文中，我们专注于进行公平性统计推断。以往关于公平性推断的研究主要集中于推断给定预测算法的公平性属性。在这里，我们通过评估数据生成过程本身的公平性来扩展公平性推断，此处将其称为数据公平性。我们使用目标学习（一种灵活的非参数推断框架）对数据公平性进行推断。我们推导出人口统计学均等、平等机会和条件互信息等估计量。此外，我们发现我们用于概率指标的估计量具有双重稳健性。为了验证我们的方法，我们进行了多次模拟，并将我们的估计量应用于真实数据。
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English: The influence of spatial dimensionality and particle-antiparticle pair
production on the thermodynamic properties of the relativistic Fermi gas, at
finite chemical potential, is studied. Resembling a kind of phase transition,
qualitatively different behaviors of the thermodynamic susceptibilities, namely
the isothermal compressibility and the specific heat, are markedly observed at
different temperature regimes as function of the system dimensionality and of
the rest mass of the particles. A minimum in the isothermal compressibility
marks a characteristic temperature, in the range of tenths of the Fermi
temperature, at which the system transit from a normal phase, to a phase where
the gas compressibility grows as a power law of the temperature. Curiously, we
find that for a particle density of a few times the density of nuclear matter,
and rest masses of the order of 10 MeV, the minimum of the compressibility
occurs at approximately 170 MeV/k, which roughly estimates the critical
temperature of hot fermions as those occurring in the gluon-quark plasma phase
transition.
Chinese: 研究了有限化学势下，空间维度和粒子-反粒子对产生对相对论费米气热力学性质的影响。类似于某种相变，等温压缩系数和比热这些热力学磁化率表现出随系统维度和粒子静止质量的温度区间的定性不同行为。等温压缩系数的极小值标记了一个特征温度，该温度在费米温度的十分之一范围内，系统从正常相转变为气体压缩率随温度呈幂律增长的相。有趣的是，我们发现对于粒子密度为核物质密度的几倍，且静止质量为10 MeV量级的情形，压缩系数的极小值出现在约170 MeV/k处，这大致估计了高温费米子（如胶子-夸克等离子体相变中出现的）的临界温度。
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English: We treat three recurrences involving square roots, the first of which arises
from an infinite simple radical expansion for the Golden mean, whose precise
convergence rate was made famous by Richard Bruce Paris in 1987. A
never-before-seen proof of an important formula is given. The other recurrences
are non-exponential yet equally interesting. Asymptotic series developed for
each of these two examples feature a constant, dependent on the initial
condition but otherwise intrinsic to the function at hand.
Chinese: 我们处理了三个涉及平方根的递归，其中第一个来源于黄金比例的无穷简单根式展开，其精确收敛率在1987年由理查德·布鲁斯·帕里斯使之闻名。给出了一个重要公式的首次未见证明。其他递归虽然不是指数性的，但同样有趣。为这两个例子各自开发的渐近级数都包含一个常数，这个常数依赖于初始条件，但在其他方面是手头函数的内在属性。
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English: Video captioning is a critical task in the field of multimodal machine
learning, aiming to generate descriptive and coherent textual narratives for
video content. While large vision-language models (LVLMs) have shown
significant progress, they often struggle to capture the causal and temporal
dynamics inherent in complex video sequences. To address this limitation, we
propose an enhanced framework that integrates a Causal-Temporal Reasoning
Module (CTRM) into state-of-the-art LVLMs. CTRM comprises two key components:
the Causal Dynamics Encoder (CDE) and the Temporal Relational Learner (TRL),
which collectively encode causal dependencies and temporal consistency from
video frames. We further design a multi-stage learning strategy to optimize the
model, combining pre-training on large-scale video-text datasets, fine-tuning
on causally annotated data, and contrastive alignment for better embedding
coherence. Experimental results on standard benchmarks such as MSVD and MSR-VTT
demonstrate that our method outperforms existing approaches in both automatic
metrics (CIDEr, BLEU-4, ROUGE-L) and human evaluations, achieving more fluent,
coherent, and relevant captions. These results validate the effectiveness of
our approach in generating captions with enriched causal-temporal narratives.
Chinese: 视频字幕生成是多模态机器学习领域的一项关键任务，旨在为视频内容生成描述性和连贯的文本叙述。虽然大型视觉-语言模型（LVLMs）已经取得了显著进展，但它们往往难以捕捉复杂视频序列中固有的因果和时序动态。为了解决这一局限性，我们提出了一种增强型框架，该框架将因果-时序推理模块（CTRM）集成到最先进的LVLMs中。CTRM包括两个关键组件：因果动态编码器（CDE）和时序关系学习器（TRL），它们共同从视频帧中编码因果依赖和时序一致性。我们进一步设计了一种多阶段学习策略来优化模型，结合在大规模视频-文本数据集上的预训练、在因果标注数据上的微调和对比对齐以实现更好的嵌入一致性。在MSVD和MSR-VTT等标准基准上的实验结果表明，我们的方法在自动指标（CIDEr、BLEU-4、ROUGE-L）和人工评估方面都优于现有方法，实现了更流畅、连贯和相关的字幕。这些结果验证了我们的方法在生成具有丰富因果-时序叙述字幕方面的有效性。
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English: In this research note we introduce a new approximation of photon geodesics in
Schwarzschild spacetime which is especially useful to describe highly bent
trajectories, for which the angle between the initial emission position and the
line of sight to the observer approaches $\pi$: this corresponds to the points
behind the central mass of the Schwarzschild metric with respect to the
observer. The approximation maintains very good accuracy overall, with
deviations from the exact numerical results below $1\%$ up to the innermost
stable circular orbit (ISCO) located at $6~GM/c^2$.
Chinese: 在本研究简报中，我们介绍了一种新的Schwarzschild时空中的光子测地线近似方法，该方法特别适用于描述高度弯曲的轨迹，其中初始发射位置与观测者视线之间的角度接近π：这对应于相对于观测者位于Schwarzschild度规中心质量之后的点。该近似在整个过程中保持了非常高的精度，与精确数值结果的偏差低于1%，直至位于6~GM/c^2的最近稳定圆轨道（ISCO）。
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English: The Tolman VII space-time is one of the few physically acceptable exact
solutions in general relativity. In this paper, we derive a generalised Tolman
VII solution which includes a charge and a cosmological constant. We analyse
the spatial geometry of the solution and present conditions for zero and
non-zero spatial curvature. We show that for a particular value of the
boundary, the Tolman VII space-time can be matched to the charged Nariai
space-time. This represents a new class of interior Nariai solutions. Matching
with the Reissner-Nordstr\"om-de Sitter space-time, we derive analytic
expressions for the metric functions and the pressure. Using this, we show that
the solution allows for trapped null geodesics for a broad range of values for
the total charge, central density, and the cosmological constant. We
investigate the physical properties and derive an equation of state for the
fluid. We show that the fluid can be considered a polytrope with, $\Gamma \sim
2.5$. Finally, we analyse the sound speed and energy conditions to conclude
that only a subclass of the solution follows all the basic physical
acceptability criteria.
Chinese: 托尔曼七维时空是广义相对论中少数几个物理上可接受的精确解之一。在本文中，我们推导了一个包含电荷和宇宙学常数的广义托尔曼七维解。我们分析了该解的空间几何，并提出了零和非零空间曲率的条件。我们证明，对于边界的一个特定值，托尔曼七维时空可以与带电纳里时空匹配。这代表了一种新的内部纳里解类别。通过与里夏德-诺德斯特龙-德西特时空匹配，我们推导出度规函数和压力的解析表达式。利用这些结果，我们表明该解在总电荷、中心密度和宇宙学常数的广泛取值范围内允许存在束缚类光测地线。我们研究了该解的物理性质，并推导出流体的状态方程。我们证明该流体可以被视为多方体，其中$\Gamma \sim 2.5$。最后，我们分析了声速和能量条件，得出结论：只有该解的子类满足所有基本物理可接受性标准。
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English: Many Internet of Things and embedded projects are event-driven, and therefore
require asynchronous and concurrent programming. Current proposals for C++20
suggest that coroutines will have native language support. It is timely to
survey the current use of coroutines in embedded systems development. This
paper investigates existing research which uses or describes coroutines on
resource-constrained platforms. The existing research is analysed with regard
to: software platform, hardware platform and capacity; use cases and intended
benefits; and the application programming interface design used for coroutines.
A systematic mapping study was performed, to select studies published between
2007 and 2018 which contained original research into the application of
coroutines on resource-constrained platforms. An initial set of 566 candidate
papers were reduced to only 35 after filters were applied, revealing the
following taxonomy. The C & C++ programming languages were used by 22 studies
out of 35. As regards hardware, 16 studies used 8- or 16-bit processors while
13 used 32-bit processors. The four most common use cases were concurrency (17
papers), network communication (15), sensor readings (9) and data flow (7). The
leading intended benefits were code style and simplicity (12 papers),
scheduling (9) and efficiency (8). A wide variety of techniques have been used
to implement coroutines, including native macros, additional tool chain steps,
new language features and non-portable assembly language. We conclude that
there is widespread demand for coroutines on resource-constrained devices. Our
findings suggest that there is significant demand for a formalised, stable,
well-supported implementation of coroutines in C++, designed with consideration
of the special needs of resource-constrained devices, and further that such an
implementation would bring benefits specific to such devices.
Chinese: 许多物联网和嵌入式项目都是事件驱动的，因此需要异步和并发编程。目前的C++20提案建议协程将获得原生语言支持。调查嵌入式系统开发中协程的当前使用情况是及时的。本文研究了在资源受限平台上使用或描述协程的现有研究。现有研究从以下方面进行了分析：软件平台、硬件平台和容量；用例和预期效益；以及用于协程的应用程序编程接口设计。进行了一项系统映射研究，以选择2007年至2018年间发表的、包含对资源受限平台上协程应用原创研究的论文。经过筛选，最初的566篇候选论文减少到只有35篇，揭示了以下分类。35篇论文中有22篇使用了C和C++编程语言。就硬件而言，16篇研究使用了8位或16位处理器，而13篇使用了32位处理器。最常见的四个用例是并发（17篇论文）、网络通信（15篇）、传感器读取（9篇）和数据流（7篇）。最主要的预期效益是代码风格和简单性（12篇论文）、调度（9篇）和效率（8篇）。已经使用了各种技术来实现协程，包括原生宏、额外的工具链步骤、新的语言特性和不可移植的汇编语言。我们得出结论，在资源受限设备上对协程的需求很广泛。我们的发现表明，对C++中形式化、稳定、良好支持的协程实现有显著需求，这种实现考虑到资源受限设备的特殊需求，并且进一步表明这种实现将为这类设备带来特定的好处。
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English: The current success of Graph Neural Networks (GNNs) usually relies on loading
the entire attributed graph for processing, which may not be satisfied with
limited memory resources, especially when the attributed graph is large. This
paper pioneers to propose a Binary Graph Convolutional Network (Bi-GCN), which
binarizes both the network parameters and input node attributes and exploits
binary operations instead of floating-point matrix multiplications for network
compression and acceleration. Meanwhile, we also propose a new gradient
approximation based back-propagation method to properly train our Bi-GCN.
According to the theoretical analysis, our Bi-GCN can reduce the memory
consumption by an average of ~31x for both the network parameters and input
data, and accelerate the inference speed by an average of ~51x, on three
citation networks, i.e., Cora, PubMed, and CiteSeer. Besides, we introduce a
general approach to generalize our binarization method to other variants of
GNNs, and achieve similar efficiencies. Although the proposed Bi-GCN and
Bi-GNNs are simple yet efficient, these compressed networks may also possess a
potential capacity problem, i.e., they may not have enough storage capacity to
learn adequate representations for specific tasks. To tackle this capacity
problem, an Entropy Cover Hypothesis is proposed to predict the lower bound of
the width of Bi-GNN hidden layers. Extensive experiments have demonstrated that
our Bi-GCN and Bi-GNNs can give comparable performances to the corresponding
full-precision baselines on seven node classification datasets and verified the
effectiveness of our Entropy Cover Hypothesis for solving the capacity problem.
Chinese: 当前图神经网络（GNNs）的成功通常依赖于加载整个属性图进行处理，这在有限的内存资源下可能无法满足，尤其是在属性图较大的情况下。本文开创性地提出了一种二值图卷积网络（Bi-GCN），该网络将网络参数和输入节点属性二值化，并利用二值运算代替浮点矩阵乘法来实现网络压缩和加速。同时，我们还提出了一种基于新的梯度近似反向传播方法来适当训练我们的Bi-GCN。根据理论分析，我们的Bi-GCN在三篇引文网络（即Cora、PubMed和CiteSeer）上，可以平均减少网络参数和输入数据的内存消耗约31倍，并平均加速推理速度约51倍。此外，我们介绍了一种通用方法来将我们的二值化方法推广到其他GNN变体，并实现相似的效率。尽管所提出的Bi-GCN和Bi-GNNs简单而高效，但这些压缩网络也可能存在潜在的容量问题，即它们可能没有足够的存储容量来学习特定任务的充分表示。为了解决容量问题，我们提出了一个熵覆盖假设来预测Bi-GNN隐藏层宽度的下限。大量实验表明，我们的Bi-GCN和Bi-GNNs在七个节点分类数据集上可以与相应的全精度基线提供相当的性能，并验证了我们的熵覆盖假设在解决容量问题上的有效性。
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English: Epitaxial Mn-doped BiFeO3 (MBFO) thin films were grown on GaAs (001)
substrate with SrTiO3 (STO) buffer layer by pulsed laser deposition. X-ray
diffraction results demonstrate that the films show pure (00l) orientation, and
MBFO(100)//STO(100), whereas STO (100)//GaAs (110). Piezoresponse force
microscopy images and polarization versus electric field loops indicate that
the MBFO films grown on GaAs have an effective ferroelectric switching. The
MBFO films exhibit good ferroelectric behavior (2Pr ~ 92 {\mu}C/cm2 and 2EC ~
372 kV/cm). Ferromagnetic property with saturated magnetization of 6.5 emu/cm3
and coercive field of about 123 Oe is also found in the heterostructure at room
temperature.
Chinese: 外延式Mn掺杂BiFeO3（MBFO）薄膜通过脉冲激光沉积法生长在GaAs（001）衬底上，并带有SrTiO3（STO）缓冲层。X射线衍射结果表明，薄膜表现出纯（00l）取向，MBFO(100)//STO(100)，而STO (100)//GaAs (110)。压电响应力显微镜图像和极化与电场环表明，在GaAs上生长的MBFO薄膜具有有效的铁电开关。MBFO薄膜表现出良好的铁电行为（2Pr ~ 92 μC/cm2和2EC ~ 372 kV/cm）。在室温下，异质结构中还发现了具有饱和磁化强度为6.5 emu/cm3和约123 Oe矫顽场的铁磁性。
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English: We investigate the statistics of fluctuations in a classical stochastic
network of nodes joined by connectors. The nodes carry generalized charge that
may be randomly transferred from one node to another. Our goal is to find the
time evolution of the probability distribution of charges in the network. The
building blocks of our theoretical approach are (1) known probability
distributions for the connector currents, (2) physical constraints such as
local charge conservation, and (3) a time-scale separation between the slow
charge dynamics of the nodes and the fast current fluctuations of the
connectors. We derive a stochastic path integral representation of the
evolution operator for the slow charges. Once the probability distributions on
the discrete network have been studied, the continuum limit is taken to obtain
a statistical field theory. We find a correspondence between the diffusive
field theory and a Langevin equation with Gaussian noise sources, leading
nevertheless to non-trivial fluctuation statistics. To complete our theory, we
demonstrate that the cascade diagrammatics, recently introduced by Nagaev,
naturally follows from the stochastic path integral. We extend the
diagrammatics to calculate current correlation functions for an arbitrary
network. One primary application of this formalism is that of full counting
statistics (FCS). We stress however, that the formalism is suitable for general
classical stochastic problems as an alternative to the traditional master
equation or Doi-Peliti technique. The formalism is illustrated with several
examples: both instantaneous and time averaged charge fluctuation statistics in
a mesoscopic chaotic cavity, as well as the FCS and new results for a
generalized diffusive wire.
Chinese: 我们研究了由连接器连接的节点组成的经典随机网络中涨落的统计性质。这些节点携带广义电荷，这种电荷可能随机地在节点之间转移。我们的目标是找到网络中电荷概率分布的时间演化。我们理论方法的基础是：(1) 已知的连接器电流概率分布，(2) 物理约束条件（如局部电荷守恒），以及 (3) 节点缓慢电荷动力学与连接器快速电流涨落之间的时间尺度分离。我们推导出慢电荷演化算子的随机路径积分表示。一旦研究了离散网络上的概率分布，就取连续极限以获得统计场论。我们发现扩散场论与具有高斯噪声源的朗之万方程之间存在对应关系，尽管如此仍导致非平凡的涨落统计。为了完善我们的理论，我们证明了Nagaev最近引入的级联图示法自然地源于随机路径积分。我们将图示法扩展到计算任意网络的电流相关函数。这种形式主义的一个主要应用是全计数统计（FCS）。然而，我们强调，这种形式主义适用于一般的经典随机问题，作为传统主方程或Doi-Peliti技术的替代方案。我们通过几个例子说明了这种形式主义：介观混沌腔中的瞬时和时间平均电荷涨落统计，以及广义扩散导线中的FCS和新结果。
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English: Strange metals exhibit universal linear-in-temperature resistivity described
by a Planckian scattering rate, the origin of which remains elusive. By
employing a novel approach inspired by quantum optics, we arrive at the
coherent state representation of lattice vibrations: quantum acoustics.
Utilizing this nonperturbative framework, we demonstrate that lattice
vibrations could serve as active drivers in the Planckian resistivity
phenomenon, challenging prevailing theories. By treating charge carriers as
quantum wave packets negotiating the dynamic acoustic field, we find that a
competition ensues between localization and delocalization giving rise to the
previously conjectured universal quantum bound of diffusion, $\hbar/m^{*}$,
independent of temperature or any other material parameters. This leads to the
enigmatic $T$-linear resistivity over hundreds of degrees, except at very low
temperatures. Quantum diffusion also explains why strange metals have much
higher electrical resistivity than typical metals. Our work elucidates the
critical role of phonons in Planckian resistivity from a new perspective and
reconsiders their significance in the transport properties of strange metals.
Chinese: 奇异金属表现出由普朗克散射率描述的普遍线性温度电阻率，其起源仍然难以捉摸。通过采用受量子光学启发的创新方法，我们得到了晶格振动的相干态表示：量子声学。利用这个非微扰框架，我们证明晶格振动可以作为普朗克电阻率现象的主动驱动因素，挑战了现有的理论。通过将电荷载体视为在动态声场中协商的量子波包，我们发现局部化和非局部化之间的竞争导致了先前推测的普适性量子扩散界限 $\hbar/m^{*}$，与温度或任何其他材料参数无关。这导致了数百度范围内的神秘 $T$-线性电阻率，除了在非常低的温度下。量子扩散还解释了为什么奇异金属的电导率比典型金属高得多。我们的工作从新的角度阐明了声子在普朗克电阻率中的关键作用，并重新考虑了它们在奇异金属传输性质中的重要性。
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English: The combination of the Cylindrical Profile Model (CPM) and Avitzur's model is
commonly used to determine flow stress curves in material testing using
compression test. In this process, stress is corrected for friction using
Avitzur's model and the average strain is calculated from CPM. This study
proposes a method for estimating strain based on Avitzur's model. The presented
case studies demonstrate the impact of this strain correction on the flow
curves. The results show that increasing friction leads to higher strain values
at the center of the sample due to barreling. The proposed method provides a
more accurate interpretation of compression test results.
Chinese: 圆柱形剖面模型（CPM）与Avitzur模型的结合常用于通过压缩试验确定材料的流动应力曲线。在此过程中，Avitzur模型用于校正摩擦力引起的应力，而CPM用于计算平均应变。本研究提出了一种基于Avitzur模型的应变估计方法。所展示的案例研究显示了这种应变校正对流动曲线影响。结果表明，随着摩擦力的增加，由于样品中心处的鼓胀现象，导致中心处的应变值更高。所提出的方法提供了一种更准确的压缩试验结果解释。
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English: In this work we extend a previously derived $n$- $^9$Be optical potential up
to 500 MeV and apply it to the system $n$- $^{12}$C, finding excellent results
for the energy dependence of the total cross sections. Results obtained with a
standard optical model calculation are compared to those from the eikonal
formalism in order to asses the accuracy of the latter as a function of the
nucleon incident energy. For comparison, single folded (s.f.) nucleon-target
potentials are also obtained using $^{12}$C densities from different models.
These potentials are sensitive to the density used and none of them reproduce
the characteristics of the phenomenological potential nor the cross section
results. We then calculate nucleus-nucleus ($NN$) potentials and total reaction
cross sections for some "normal" and exotic projectile nuclei on $ ^ {12} $C
within the eikonal formalism. We find that single folded (S.F.)
projectile-target imaginary potentials and double folded (D.F.) potentials can
produce similar energy dependence of the reaction cross sections but the S.F.
results agree better with experimental data provided the radius parameter of
the phenomenological $n$-target potential is allowed to be energy dependent. We
conclude that the results previously obtained for a $^9$Be target are quite
general, at least for light systems, and that a S.F. $NN$ potential built on a
phenomenological nN potential can constitute an interesting and useful
alternative to D.F. potentials.
Chinese: 在这项工作中，我们将先前推导出的n-$^9$Be光学势扩展到500 MeV，并将其应用于n-$^{12}$C系统，发现在总截面能量依赖性方面取得了优秀的结果。使用标准光学模型计算得到的结果与基于eikonal形式的计算结果进行比较，以评估后者作为中子入射能量的函数的准确性。为了比较，还使用不同模型中的$^{12}$C密度得到了单折叠（s.f.）中子-靶势。这些势对所用的密度很敏感，并且没有一个能够重现现象学势的特性或截面结果。然后，我们在eikonal形式主义框架内计算了一些“正常”和奇异弹头核在$^{12}$C上的核-核（$NN$）势和总反应截面。我们发现，单折叠（S.F.）弹头-靶虚势和双折叠（D.F.）势可以产生类似反应截面能量依赖性，但前提是现象学$n$-靶势的半径参数允许能量依赖。我们得出结论，先前为$^9$Be靶获得的结果相当普遍，至少对于轻系统来说如此，并且基于现象学nN势构建的单折叠$NN$势可以构成双折叠势的一个有趣且有用的替代方案。
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English: X-ray free-electron lasers (XFELs) utilize high-density and high-energy
electron bunches which are well-suited to produce Compton back-scattering
radiation. Here we study back-scattered radiation pulses produced by the
interaction of XFEL electron beams and an optical laser. We discuss
cost-effective setups to study such processes, taking advantage of the existing
conventional as well as proposed XFEL infrastructure. We estimate parameters of
possible experiments and compare them with other projects under construction.
Chinese: X射线自由电子激光（XFELs）利用高密度和高能的电子束，这些电子束非常适合产生康普顿背散射辐射。在这里，我们研究XFEL电子束与光学激光相互作用产生的背散射辐射脉冲。我们讨论利用现有以及提议的XFEL基础设施来研究此类过程的成本效益方案。我们估算可能实验的参数，并将其与其他正在建设的项目进行比较。
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English: We present a study of the $N^*(1535)$ resonance electroexcitation in a
soft-wall AdS/QCD model. Both the transverse $A_{1/2}^p$ and longitudinal
$S_{1/2}^p$ helicity amplitudes are calculated resulting in good agreement with
data and with the MAID parametrization.
Chinese: 我们研究了软壁AdS/QCD模型中$N^*(1535)$共振的电激发。计算了横向$A_{1/2}^p$和纵向$S_{1/2}^p$螺旋性振幅，结果与实验数据及MAID参数化结果吻合良好。
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English: This paper contains corrections to Madea, Rosenberg, Torres-Ardila, "The
Geometry of Loop Spaces II: Characteristic Classes," Advances in Math. (287),
2016, 485-518. The main change is that results about $\pi_1({\rm Diff}(M))$ are
replaced by results about $\pi_1({\rm Isom}(M))$, where Diff$(M)$, Isom$(M)$
refer to the diffeomorphism and isometry group of the manifold $M$.
Chinese: 本文包含对Madea、Rosenberg、Torres-Ardila的论文《Loop Spaces II: Characteristic Classes》的修正，该论文发表于《Advances in Math.》第287期，2016年，第485-518页。主要变化是将关于${\rm Diff}(M)$的$\pi_1$结果替换为关于${\rm Isom}(M)$的$\pi_1$结果，其中Diff$(M)$和Isom$(M)$分别指流形$M$的微分同胚群和等距群。
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English: Ultrafast optical frequency combs allow for both high spectral and temporal
resolution in molecular spectroscopy and have become a powerful tool in many
areas of chemistry and physics. Ultrafast lasers and frequency combs generated
from ultrafast mode-locked lasers often need to be converted to other
wavelengths. Commonly used wavelength conversions are optical parametric
oscillators, which require an external optical cavity, and supercontinuum
generation combined with optical parametric amplifiers. Whether commercial or
home-built, these systems are complex and costly. Here we propose an
alternative, simple, and easy-to-implement approach to tunable frequency comb
ultrafast lasers enabled by new continuous-wave laser technology. Sum-frequency
generation between a Nd:YAG continuous-wave laser and a Yb:fiber femtosecond
frequency comb in a beta-barium borate (BBO) crystal is explored. The resulting
sum-frequency beam is a pulsed frequency comb with the same repetition rate as
the Yb:fiber source. SNLO simulation software was used to simulate the results
and provide benchmarks for designing future system to achieve wavelength
conversion and tunability in difficult spectral regions.
Chinese: 超快光学频率梳在分子光谱学中实现了高光谱和高时间分辨率，已成为化学和物理许多领域的强大工具。超快激光器和由超快锁模激光器产生的频率梳通常需要转换到其他波长。常用的波长转换方法包括需要外部光学腔的光参量振荡器，以及与光参量放大器结合的超连续谱产生。无论是商业产品还是自行搭建，这些系统都复杂且昂贵。在这里，我们提出了一种基于新型连续波激光技术的新型可调谐频率梳超快激光器的替代方案，该方法简单且易于实现。在β-钡硼（BBO）晶体中探索了 Nd:YAG 连续波激光器和 Yb:光纤飞秒频率梳之间的和频产生。产生的和频光束是一个脉冲频率梳，其重复率与 Yb:光纤源相同。使用 SNLO 仿真软件对结果进行模拟，并为设计未来系统以在困难的光谱区域实现波长转换和调谐提供基准。
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English: We present HadaCore, a modified Fast Walsh-Hadamard Transform (FWHT)
algorithm optimized for the Tensor Cores present in modern GPU hardware.
HadaCore follows the recursive structure of the original FWHT algorithm,
achieving the same asymptotic runtime complexity but leveraging a
hardware-aware work decomposition that benefits from Tensor Core acceleration.
This reduces bottlenecks from compute and data exchange. On Nvidia A100 and
H100 GPUs, HadaCore achieves speedups of 1.1-1.4x and 1.0-1.3x, with a peak
gain of 3.5x and 3.6x respectively, when compared to the existing
state-of-the-art implementation of the original algorithm. We also show that
when using FP16 or BF16, our implementation is numerically accurate, enabling
comparable accuracy on MMLU benchmarks when used in an end-to-end Llama3
inference run with quantized (FP8) attention.
Chinese: 我们提出了HadaCore，这是一种针对现代GPU硬件中存在的Tensor Core进行优化的修改版快速沃尔什-哈达玛变换（FWHT）算法。
HadaCore遵循原始FWHT算法的递归结构，实现了相同的渐近运行时间复杂度，同时利用了硬件感知的工作分解，从而受益于Tensor Core加速。
这减少了计算和数据交换的瓶颈。在Nvidia A100和H100 GPU上，与原始算法现有的最先进实现相比，HadaCore实现了1.1-1.4倍和1.0-1.3倍的速度提升，峰值增益分别为3.5倍和3.6倍。
我们还展示了当使用FP16或BF16时，我们的实现是数值准确的，在端到端Llama3推理运行中使用量化（FP8）注意力时，能够在MMLU基准测试中实现可比的精度。
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English: Epitaxial semiconducting NiYBi thin films were directly prepared on MgO(100)
substrates by magnetron sputtering. The intensity ratio of the (200) and (400)
diffraction peaks, I(200)/I(400) = 2.93, was close to the theoretical value
(3.03). The electronic structure of NiYBi was calculated using WIEN2k and a
narrow indirect band gap of width 210 meV was found. The valence band spectra
of the films obtained by linear dichroism in hard X-ray photoelectron
spectroscopy exhibit clear structures that are in good agreement with the
calculated band structure of NiYBi.
Chinese: 外延半导体NiYBi薄膜通过磁控溅射直接制备在MgO(100)衬底上。(200)和(400)衍射峰的强度比，I(200)/I(400) = 2.93，接近理论值（3.03）。使用WIEN2k计算了NiYBi的电子结构，发现了一个宽度为210 meV的窄间接带隙。通过硬X射线光电子能谱中的线性二色性获得的薄膜价带光谱显示出与NiYBi计算带结构良好一致的结构。
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English: Self-supervised learning is a powerful way to learn useful representations
from natural data. It has also been suggested as one possible means of building
visual representation in humans, but the specific objective and algorithm are
unknown. Currently, most self-supervised methods encourage the system to learn
an invariant representation of different transformations of the same image in
contrast to those of other images. However, such transformations are generally
non-biologically plausible, and often consist of contrived perceptual schemes
such as random cropping and color jittering. In this paper, we attempt to
reverse-engineer these augmentations to be more biologically or perceptually
plausible while still conferring the same benefits for encouraging robust
representation. Critically, we find that random cropping can be substituted by
cortical magnification, and saccade-like sampling of the image could also
assist the representation learning. The feasibility of these transformations
suggests a potential way that biological visual systems could implement
self-supervision. Further, they break the widely accepted spatially-uniform
processing assumption used in many computer vision algorithms, suggesting a
role for spatially-adaptive computation in humans and machines alike. Our code
and demo can be found here.
Chinese: 自监督学习是一种从自然数据中学习有用表示的强大方式。它也被建议作为人类建立视觉表示的一种可能手段，但具体目标和算法尚不清楚。目前，大多数自监督方法鼓励系统学习同一图像的不同变换下的不变表示，而不是其他图像的变换。然而，这样的变换通常不具备生物学上的合理性，并且常常包含人为设计的感知方案，如随机裁剪和颜色抖动。在本论文中，我们尝试将这些增强操作反向工程为更具有生物学或感知上的合理性，同时仍能提供鼓励稳健表示的相同好处。关键的是，我们发现随机裁剪可以被皮质放大所替代，并且类似于眼跳的图像采样也能帮助表示学习。这些变换的可行性表明生物视觉系统可能实施自监督的一种潜在方式。此外，它们打破了广泛接受的、许多计算机视觉算法中使用的空间均匀处理假设，暗示了人类和机器中空间自适应计算的角色。我们的代码和演示可以在这里找到。
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English: The true online TD({\lambda}) algorithm has recently been proposed (van
Seijen and Sutton, 2014) as a universal replacement for the popular
TD({\lambda}) algorithm, in temporal-difference learning and reinforcement
learning. True online TD({\lambda}) has better theoretical properties than
conventional TD({\lambda}), and the expectation is that it also results in
faster learning. In this paper, we put this hypothesis to the test.
Specifically, we compare the performance of true online TD({\lambda}) with that
of TD({\lambda}) on challenging examples, random Markov reward processes, and a
real-world myoelectric prosthetic arm. We use linear function approximation
with tabular, binary, and non-binary features. We assess the algorithms along
three dimensions: computational cost, learning speed, and ease of use. Our
results confirm the strength of true online TD({\lambda}): 1) for sparse
feature vectors, the computational overhead with respect to TD({\lambda}) is
minimal; for non-sparse features the computation time is at most twice that of
TD({\lambda}), 2) across all domains/representations the learning speed of true
online TD({\lambda}) is often better, but never worse than that of
TD({\lambda}), and 3) true online TD({\lambda}) is easier to use, because it
does not require choosing between trace types, and it is generally more stable
with respect to the step-size. Overall, our results suggest that true online
TD({\lambda}) should be the first choice when looking for an efficient,
general-purpose TD method.
Chinese: 最近，真正的在线TD({\lambda})算法被提出（van Seijen和Sutton，2014）作为时间差分学习和强化学习中流行TD({\lambda})算法的通用替代品。真正的在线TD({\lambda})比传统的TD({\lambda})具有更好的理论特性，并且预期它也能导致更快的学习。在本文中，我们将这一假设付诸实践。具体来说，我们比较了真正的在线TD({\lambda})在具有挑战性的例子、随机马尔可夫奖励过程以及一个现实世界的肌电图假肢上的性能。我们使用线性函数近似，包括表格、二进制和非二进制特征。我们从三个维度评估算法：计算成本、学习速度和易用性。我们的结果证实了真正的在线TD({\lambda})的优势：1）对于稀疏特征向量，相对于TD({\lambda})的计算开销最小；对于非稀疏特征，计算时间最多是TD({\lambda})的两倍；2）在所有领域/表示中，真正的在线TD({\lambda})的学习速度通常更好，但永远不会比TD({\lambda})差；3）真正的在线TD({\lambda})更容易使用，因为它不需要在迹类型之间进行选择，并且它在步长方面通常更稳定。总的来说，我们的结果表明，在寻找高效、通用的TD方法时，真正的在线TD({\lambda})应该是首选。
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English: We investigate the behaviour of the accretion discs in the outbursts of the
low-mass black-hole X-ray binaries (BHXRB), an overview of which we have
presented previously. Almost all of the systems in which there are sufficient
observations in the most disc dominated states show a variation of the disc
luminosity with temperature close to L ~\propto T^4. This in turn implies that
in these states, the disc radius, R_in, and the colour correction factor,
f_col, are almost constant. Deviations away from the T^4 law are observed at
the beginning and end of the most disc dominated states, during the
intermediate states. Although these could be explained by an inward motion of
the accretion disc, they are more likely to be the result of an increase in the
value of f_col as the disc fraction decreases. By comparing the expected and
observed disc luminosities, we place approximate limits on the allowed
distances and masses of the BHXRB system. In a number of cases, the measured
distances and masses of the BHXRB system indicate that it is possible that the
black hole may be spinning.
Chinese: 我们研究了低质量黑洞X射线双星（BHXRB）爆发中吸积盘的行为，我们之前已经对其进行了概述。几乎所有在大多数吸积盘主导状态下有足够观测数据的系统都显示出吸积盘亮度与温度接近L ~\propto T^4的关系。这反过来又意味着在这些状态下，吸积盘半径R_in和颜色校正因子f_col几乎是恒定的。在大多数吸积盘主导状态的开头和结尾，以及在中间状态下，观察到偏离T^4定律的现象。尽管这些可能可以通过吸积盘向内运动来解释，但它们更有可能是由于随着吸积盘分数的减少，f_col值的增加所致。通过比较预期的和观测到的吸积盘亮度，我们对BHXRB系统的允许距离和质量设定了近似限制。在许多情况下，BHXRB系统的测量距离和质量表明，黑洞可能正在旋转。
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English: The task of video grounding, which temporally localizes a natural language
description in a video, plays an important role in understanding videos.
Existing studies have adopted strategies of sliding window over the entire
video or exhaustively ranking all possible clip-sentence pairs in a
pre-segmented video, which inevitably suffer from exhaustively enumerated
candidates. To alleviate this problem, we formulate this task as a problem of
sequential decision making by learning an agent which regulates the temporal
grounding boundaries progressively based on its policy. Specifically, we
propose a reinforcement learning based framework improved by multi-task
learning and it shows steady performance gains by considering additional
supervised boundary information during training. Our proposed framework
achieves state-of-the-art performance on ActivityNet'18 DenseCaption dataset
and Charades-STA dataset while observing only 10 or less clips per video.
Chinese: 视频 grounding 任务，即把自然语言描述在视频中时间定位，在理解视频方面发挥着重要作用。现有研究采用了在整个视频中滑动窗口或穷尽式排序预分割视频中所有可能片段-句子对等策略，这些方法不可避免地存在候选穷尽枚举问题。为了缓解这个问题，我们将这个任务定义为序列决策问题，通过学习一个智能体，使其根据策略逐步调节时间 grounding 边界。具体地，我们提出了一个基于强化学习的框架，通过在训练过程中考虑额外的监督边界信息得到改进，并表现出稳定的性能提升。我们的框架在 ActivityNet'18 DenseCaption 数据集和 Charades-STA 数据集上实现了当前最佳性能，同时每个视频只需观察 10 个或更少的片段。
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English: In this paper, we study fixed points of N-point gravitational lenses. We use
complex form of lens mapping to study fixed points. Complex form has an
advantage over coordinate one because we can describe N-point gravitational
lens by system of two equation in coordinate form and we can describe it by one
equation in complex form. We can easily transform the equation, which describe
N-point gravitational lens, into polynomial equation that is convenient to use
for our research. In our work, we present lens mapping as a linear combination
of two mapping: complex analytical and identity mapping. Analytical mapping is
specified by analytical function (deflection function). We studied necessary
and sufficient conditions for the existence of deflection function and proved
some theorems. Deflection function is analytical, rational, its zeroes are
fixed points of lens mapping and their number is from 1 to N-1, poles of
deflection function are coordinates of point masses, all poles are simple, the
residues at the poles are equal to the value of point masses.\\ We used
Gauss-Lucas theorem and proved that all fixed points of lens mapping are in the
convex polygon. Vertices of the polygon consist of point masses. We proved
theorem that can be used to find all fixed point of lens mapping. On the basis
of the above, we conclude that one-point gravitational lens has no fixed
points, 2-point lens has only 1 fixed point, 3-point lens has 1 or 2 fixed
points. Also we present expressions to calculate fixed points in 2-point and
3-point gravitational lenses. We present some examples of parametrization of
point masses and distribution of fixed points for this parametrization.
Chinese: 在本文中，我们研究了N点重力透镜的不动点。我们使用复数形式的透镜映射来研究不动点。与坐标形式相比，复数形式具有优势，因为我们可以用坐标形式的两个方程来描述N点重力透镜，也可以用一个方程来描述它。我们很容易将描述N点重力透镜的方程转换为便于我们研究使用的多项式方程。在我们的工作中，我们将透镜映射表示为两种映射的线性组合：复解析映射和恒等映射。解析映射由解析函数（偏转函数）指定。我们研究了偏转函数存在的必要和充分条件，并证明了一些定理。偏转函数是解析的、有理的，其零点是透镜映射的不动点，其数量从1到N-1，偏转函数的极点是点质量的坐标，所有极点都是简单的，极点处的留数等于点质量的值。我们使用高斯-卢卡斯定理证明了透镜映射的所有不动点都在凸多边形内，该多边形的顶点由点质量组成。我们证明了一个定理，可以用来找到透镜映射的所有不动点。基于以上结论，我们得出结论：单点重力透镜没有不动点，2点透镜只有一个不动点，3点透镜有1个或2个不动点。我们还给出了2点和3点重力透镜中计算不动点的表达式，并提供了点质量参数化的一些示例以及该参数化下的不动点分布情况。
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English: In open-domain Question Answering (QA), dense retrieval is crucial for
finding relevant passages for answer generation. Typically, contrastive
learning is used to train a retrieval model that maps passages and queries to
the same semantic space. The objective is to make similar ones closer and
dissimilar ones further apart. However, training such a system is challenging
due to the false negative issue, where relevant passages may be missed during
data annotation. Hard negative sampling, which is commonly used to improve
contrastive learning, can introduce more noise in training. This is because
hard negatives are those closer to a given query, and thus more likely to be
false negatives. To address this issue, we propose a novel contrastive
confidence regularizer for Noise Contrastive Estimation (NCE) loss, a commonly
used loss for dense retrieval. Our analysis shows that the regularizer helps
dense retrieval models be more robust against false negatives with a
theoretical guarantee. Additionally, we propose a model-agnostic method to
filter out noisy negative passages in the dataset, improving any downstream
dense retrieval models. Through experiments on three datasets, we demonstrate
that our method achieves better retrieval performance in comparison to existing
state-of-the-art dense retrieval systems.
Chinese: 在开放域问答（QA）中，密集检索对于找到用于答案生成的相关段落至关重要。通常，对比学习用于训练一个检索模型，该模型将段落和查询映射到同一个语义空间。目标是使相似的更接近，不相似的更远。然而，由于数据标注过程中可能会遗漏相关段落，训练这样的系统具有挑战性。常用的用于改进对比学习的方法是困难负样本采样，但这会在训练中引入更多噪声。这是因为困难负样本是与给定查询更接近的样本，因此更有可能是假阴性。为了解决这个问题，我们提出了一种新的对比置信度正则化器，用于噪声对比估计（NCE）损失，这是一种常用的用于密集检索的损失函数。我们的分析表明，该正则化器有助于密集检索模型在理论上更具鲁棒性，能够抵抗假阴性。此外，我们提出了一种与模型无关的方法，用于过滤数据集中的噪声负样本，从而改进任何下游的密集检索模型。通过对三个数据集的实验，我们证明了与现有的最先进的密集检索系统相比，我们的方法实现了更好的检索性能。
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English: A phenomenological model is proposed for the analysis of the properties of
the Kaonic Nuclear Cluster (KNC) Kpp in its ground state. Inside the KNC K^-pp
we describe the relative motion of the protons in the pp pair and the motion of
the K^- meson relative to the pp pair in terms of wave functions of
3-dimensional harmonic oscillators. The interaction strength is parameterised
in our model by the frequency of the longitudinal oscillation of the K^- meson
relative to the pp pair. This parameter was determined with the binding energy
and width of the strange baryon Lambda(1405) by assuming that it is a bound
state of the K^-p pair. In terms of this interaction strength we calculate the
binding energy epsilon_(Kpp) = - 118 MeV, the partial widths of non-pionic
decay channels and the total width, Gamma_(Kpp) = 58 MeV. This agrees well with
the experimental data by the FINUDA Collaboration (PRL 94, 212303 (2005)):
epsilon_exp = - 115(+6/-5) MeV and Gamma_exp = 67(+14/-11) MeV. The discrepancy
with the results, obtained by Akaishi and Yamazaki within the potential model
approach, is discussed.
Chinese: 提出了一种现象学模型，用于分析Kaonic核簇（KNC）Kpp在其基态下的性质。在KNC K^-pp中，我们用三维谐振子的波函数描述了pp对中质子的相对运动以及K^-介子相对于pp对的运动。我们的模型通过K^-介子相对于pp对的纵向振荡频率来参数化相互作用强度。该参数通过假设它是K^-p对的束缚态，利用奇异重子Lambda(1405)的结合能和宽度来确定。在这个相互作用强度下，我们计算了结合能epsilon_(Kpp) = - 118 MeV，非π介子衰变通道的部分宽度以及总宽度，Gamma_(Kpp) = 58 MeV。这与FINUDA合作组（PRL 94, 212303 (2005)）的实验数据吻合良好：epsilon_exp = - 115(+6/-5) MeV和Gamma_exp = 67(+14/-11) MeV。关于与Akaishi和Yamazaki在势模型方法中获得的结果的差异进行了讨论。
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English: We apply the recently developed adaptive ensemble optimization technique to
simulate dense Lennard-Jones fluids and a particle-solvent model by
broad-histogram Monte Carlo techniques. Equilibration of the simulated fluid is
improved by sampling an optimized histogram in radial coordinates that shifts
statistical weight towards the entropic barriers between the shells of the
liquid. Interstitial states in the vicinity of these barriers are identified
with unprecedented accuracy by sharp signatures in the quickly converging
histogram and measurements of the local diffusivity. The radial distribution
function and potential of mean force are calculated to high precision.
Chinese: 我们将最近开发的自适应集成优化技术应用于通过广度直方图蒙特卡洛技术模拟密集的Lennard-Jones流体和粒子-溶剂模型。通过在径向坐标中采样优化的直方图，使得统计权重向液体壳层之间的熵屏障转移，从而提高了模拟流体的平衡。通过快速收敛的直方图中的尖锐特征和局部扩散率的测量，以前所未有的精度识别了这些屏障附近的间隙态。计算了径向分布函数和平均力势，精度很高。
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English: In this paper we have studied a new form of Non-Commutative (NC) phase space
with an operatorial form of noncommutativity. A point particle in this space
feels the effect of an interaction with an "{\it{internal}}" magnetic field,
that is singular at a specific position $\theta^{-1}$. By "internal" we mean
that the effective magnetic fields depends essentially on the particle
properties and modifies the symplectic structure. Here $\theta $ is the NC
parameter and induces the coupling between the particle and the "internal"
magnetic field. The magnetic moment of the particle is computed. Interaction
with an {\it{external}} physical magnetic field reveals interesting features
induced by the inherent fuzziness of the NC phase space: introduction of
non-trivial structures into the charge and mass of the particle and possibility
of the particle dynamics collapsing to a Hall type of motion. The dynamics is
studied both from Lagrangian and symplectic (Hamiltonian) points of view. The
canonical (Darboux) variables are also identified. We briefly comment, that the
model presented here, can play interesting role in the context of (recently
observed) {\it{real}} space Berry curvature in material systems.
Chinese: 在本文中，我们研究了一种具有算子形式非交换性的新型非交换（NC）相空间。在这个空间中的点粒子会受到与一个“内部”磁场相互作用的效应，该磁场在特定位置 $\theta^{-1}$ 处是奇异的。我们所说的“内部”是指有效磁场本质上依赖于粒子性质，并修改了辛结构。这里 $\theta$ 是非交换参数，它诱导了粒子与“内部”磁场的耦合。计算了粒子的磁矩。与 {\it{外部}} 物理磁场的相互作用揭示了非交换相空间固有模糊性所引起的有趣特征：将非平凡结构引入粒子的电荷和质量，以及粒子动力学可能坍缩为霍尔类型运动的可能性。我们从拉格朗日和辛（哈密顿）的观点研究了动力学。还确定了正则（Darboux）变量。我们简要评论，这里提出的模型，在（最近观测到的）材料系统中的 {\it{真实}} 空间贝里曲率背景下，可以发挥有趣的作用。
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English: It is well-known that fixed energy solutions of a reversible autonomous
Lagrangian system are up to time reparametrization geodesics of the
Jacobi-Maupertuis metric, which degenerates at the boundary of the Hill's
region. In a recent paper, Montgomery proved that geodesics hitting the
boundary at a regular point always contain pairs of focal points, and hence in
particular cannot be minima of the energy functional. Starting from this, we
provide a precise Morse index formula for periodic brake orbits of a reversible
autonomous Lagrangian system by computing the local contribution to the Morse
index provided at each brake instant. We finally discuss an application to a
doubly coupled harmonic oscillator.
Chinese: 众所周知，可逆自洽拉格朗日系统的固定能量解在时间重新参数化下是雅可比-莫波蒂乌斯度量的测地线，该度量在希尔区域的边界处退化。在最近的一篇论文中，蒙哥马利证明了在正则点触及边界的测地线总是包含焦点对，因此特别不是能量泛函的极小值。基于此，我们通过计算每个制动时刻对莫尔斯指数的局部贡献，为可逆自洽拉格朗日系统的周期制动轨道提供了一个精确的莫尔斯指数公式。最后，我们讨论了将其应用于双耦合谐振子的应用。
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English: A finite horizon linear quadratic(LQ) optimal control problem is studied for
a class of discrete-time linear fractional systems (LFSs) affected by
multiplicative, independent random perturbations. Based on the dynamic
programming technique, two methods are proposed for solving this problem. The
first one seems to be new and uses a linear, expanded-state model of the LFS.
The LQ optimal control problem reduces to a similar one for stochastic linear
systems and the solution is obtained by solving Riccati equations. The second
method appeals to the Principle of Optimality and provides an algorithm for the
computation of the optimal control and cost by using directly the fractional
system. As expected, in both cases the optimal control is a linear function in
the state and can be computed by a computer program. Two numerical examples
proves the effectiveness of each method.
Chinese: 针对受乘性独立随机扰动影响的离散时间线性分数系统（LFSs）的一类有限视界线性二次（LQ）最优控制问题进行了研究。基于动态规划技术，提出了两种求解该问题的方法。第一种方法似乎是新提出的，它使用LFS的线性扩展状态模型。LQ最优控制问题简化为随机线性系统的类似问题，并通过求解里卡蒂方程得到解。第二种方法应用最优性原理，并提供了通过直接使用分数系统来计算最优控制和成本算法。正如预期的那样，在这两种情况下，最优控制是状态的一个线性函数，并且可以通过计算机程序计算。两个数值例子证明了每种方法的有效性。
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English: These are the notes for a lecture which I presented at the International
Conference on New Frontiers in Physics in Kolymbari, Crete in July, 2018. They
review an idea which posits a phase of a two-dimensional system of cold
N-component Fermions which exhibits spontaneously broken approximate scale
symmetry when studied in the large N expansion. Near criticality, the phase
exhibits anomalously small pressure and large compressibility. Some of the
consequences of the approximate scale symmetry, such as the existence of a
dilaton and its properties are discussed.
Chinese: 这些是我在2018年7月于克里特岛柯尔姆巴里国际物理新前沿会议上所做的演讲笔记。这些笔记回顾了一个假说，该假说提出一个由冷N分量费米子组成的二维系统的相，在通过大N展开研究时，该相表现出近似尺度对称性的自发破缺。在临界点附近，该相展现出异常小的压力和大的压缩性。关于近似尺度对称性的一些后果，如稀释子的存在及其性质，进行了讨论。
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English: In this paper, we introduce two new approximation properties for \'etale
groupoids, almost elementariness and (ubiquitous) fiberwise amenability,
inspired by Matui's and Kerr's notions of almost finiteness. In fact, we show
that, in their respective scopes of applicability, both notions of almost
finiteness are equivalent to the conjunction of our two properties. These new
properties stem from viewing \'etale groupoids as coarse geometric objects in
the spirit of geometric group theory. Fiberwise amenability is a coarse
geometric property of \'etale groupoids that is closely related to the
existence of invariant measures on unit spaces and corresponds to the
amenability of the acting group in a transformation groupoid. Almost
elementariness may be viewed as a better dynamical analogue of the regularity
properties of C*-algebras than almost finiteness, since, unlike the latter, the
former may also be applied to the purely infinite case. To support this
analogy, we show almost elementary minimal groupoids give rise to tracially
Z-stable reduced groupoid C*-algebras. In particular, the reduced C*-algebras
of second countable amenable almost finite groupoids in Matui's sense are
Z-stable.
Chinese: 在本文中，我们介绍了étale群堆的两个新的逼近性质：几乎元素性和（普遍的）纤维化可和性，这些性质受到Matui和Kerr关于几乎有限性的概念启发。事实上，我们证明了，在它们各自的应用范围内，这两种关于几乎有限性的概念都等同于我们提出的两个性质。这些新性质源于将étale群堆视为几何群论精神中的粗糙几何对象。纤维化可和性是étale群堆的一种与单位空间上不变测度的存在密切相关、对应于变换群堆中作用群的可和性的粗糙几何性质。几乎元素性可以看作是比几乎有限性更好的C*-代数正则性性质的动力学类比，因为与后者不同，前者也可以应用于纯无限的情况。为了支持这种类比，我们证明了几乎元素性的极小群堆会产生可迹Z-稳定约化群堆C*-代数。特别是，Matui意义上的可数第二型可和性étale群堆的约化C*-代数是Z-稳定的。
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English: We present the first Faraday rotation measure (RM) grid study of an
individual low-mass cluster -- the Fornax cluster -- which is presently
undergoing a series of mergers. Exploiting commissioning data for the
POlarisation Sky Survey of the Universe's Magnetism (POSSUM) covering a
$\sim34$ square degree sky area using the Australian Square Kilometre Array
Pathfinder (ASKAP), we achieve an RM grid density of $\sim25$ RMs per square
degree from a 280 MHz band centred at 887 MHz, which is similar to expectations
for forthcoming GHz-frequency all-sky surveys. We thereby probe the extended
magnetoionic structure of the cluster in unprecedented detail. We find that the
scatter in the Faraday RM of confirmed background sources is increased by
$16.8\pm2.4$ rad m$^{-2}$ within 1 degree (360 kpc) projected distance to the
cluster centre, which is 2--4 times more extended than the presently-detectable
X-ray-emitting intracluster medium (ICM). The Faraday-active plasma is more
massive than the X-ray-emitting ICM, with an average density that broadly
matches expectations for the Warm-Hot Intergalactic Medium. The morphology of
the Faraday depth enhancement exhibits the classic morphology of an
astrophysical bow shock on the southwest side of the main Fornax cluster, and
an extended, swept-back wake on the northeastern side. Our favoured explanation
is an ongoing merger between the main cluster and a sub-cluster to the
southwest. The shock's Mach angle and stand-off distance lead to a
self-consistent transonic merger speed with Mach 1.06. The region hosting the
Faraday depth enhancement shows a decrement in both total and polarised
intensity. We fail to identify a satisfactory explanation for this; further
observations are warranted. Generally, our study illustrates the scientific
returns that can be expected from all-sky grids of discrete sources generated
by forthcoming all-sky radio surveys.
Chinese: 我们展示了第一个关于单个低质量星系团——Fornax星系团——的法拉第旋转测量（RM）网格研究，该星系团目前正在经历一系列的合并。利用覆盖约34平方度天空区域的宇宙磁场偏振天空调查（POSSUM）的调试数据，使用澳大利亚平方公里阵列路径探测器（ASKAP），我们从中心频率为887 MHz的280 MHz频段中实现了约25个RM每平方度的网格密度，这与即将到来的GHz频率全天空调查的预期相似。因此，我们以前所未有的详细程度探测了星系团的扩展磁电结构。我们发现，在距离星系团中心1度（360 kpc）的投影距离内，已确认的背景源的Faraday RM的散射增加了$16.8\pm2.4$ rad m$^{-2}$，这比目前可检测到的X射线发射的星系团内介质（ICM）扩展了2到4倍。Faraday活跃的等离子体比X射线发射的ICM更重，其平均密度大致符合温暖-热宇宙介质（WHIM）的预期。Faraday深度增强的形态表现出主Fornax星系团西南侧的经典天体物理弓形激波形态，以及东北侧的扩展、扫过的尾迹。我们偏爱的解释是主星系团与西南侧的子星系团正在进行合并。激波的马赫角和 standoff 距离导致了一个自洽的跨音速合并速度，马赫数为1.06。Faraday深度增强所在区域的总强度和偏振强度都出现了下降。我们未能找到令人满意的解释；需要进一步的观测。总的来说，我们的研究展示了未来全天空无线电调查产生的离散源全天空网格可以带来的科学回报。
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English: We use fractal analysis to systematically study the clustering strength of
the distribution of stars, HII regions, molecular gas, and individual giant
molecular clouds in M33 over a wide range of spatial scales. We find a clear
transition from a scale-free behavior at small spatial scales to a nearly
uniform distribution at large scales. The transition region lies in the range
500-1000 pc and it separates the regime of small-scale turbulent motion from
that of large-scale galactic dynamics. The three-dimensional fractal dimension
of bright young stars and molecular gas at small spatial scales is similar to
or less than 1.9 indicating that the interstellar medium in M33 is on average
much more fragmented and irregular than the in the Milky Way.
Chinese: 我们使用分形分析系统地研究了M33中恒星、HII区域、分子气体和单个巨型分子云在广泛的空间尺度上的聚集强度。我们发现，从小空间尺度上的无标度行为到大规模上的几乎均匀分布之间存在一个明显的转变。这个转变区域位于500-1000 pc范围内，它将小尺度湍流运动区域与大尺度银河动力学区域分开。在小空间尺度上，明亮的年轻恒星和分子气体的三维分形维度与1.9相似或更小，这表明M33中的星际介质在平均上比银河系中的要更加碎片化和不规则。
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English: We study the photocurrent induced by pulsed-light illumination (pulse
duration is several nanoseconds) of single-crystal diamond containing nitrogen
impurities. Application of additional continuous-wave light of the same
wavelength quenches pulsed photocurrent. Characterization of the optically
quenched photocurrent and its recovery is important for the development of
diamond based electronics and sensing.
Chinese: 我们研究了含有氮杂质的单晶金刚石在脉冲光照射（脉冲持续时间是几纳秒）下产生的光电流。应用相同波长的连续波光会熄灭脉冲光电流。对光学熄灭的光电流及其恢复过程的表征对于发展基于金刚石电子和传感技术非常重要。
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English: The spread of fake news remains a serious global issue; understanding and
curtailing it is paramount. One way of differentiating between deceptive and
truthful stories is by analyzing their coherence. This study explores the use
of topic models to analyze the coherence of cross-domain news shared online.
Experimental results on seven cross-domain datasets demonstrate that fake news
shows a greater thematic deviation between its opening sentences and its
remainder.
Chinese: 虚假新闻的传播仍然是一个严重的全球性问题；理解和遏制它至关重要。区分欺骗性故事和真实故事的一种方法是通过分析它们的连贯性。这项研究探讨了使用主题模型来分析在线共享的跨领域新闻的连贯性。在七个跨领域数据集上的实验结果表明，虚假新闻在其开头句子和其余部分之间表现出更大的主题偏差。
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English: We prove a conjecture of Viana which states that Lyapunov exponents vary
continuously when restricted to $GL(2,\mathbb{R})$-valued cocycles over a
subshift of finite type which admit invariant holonomies that depend
continuously on the cocycle.
Chinese: 我们证明了Viana的一个猜想，该猜想表明当Lyapunov指数被限制在依赖于 cocycle 的连续不变 holonomies 的有限型子移位上的 $GL(2,\mathbb{R})$-值 cocycles 时，它们是连续变化的。
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English: The phenomenon of a partial 2H\rightarrow1T phase transition within
multiwalled WS2 nanotubes under substitutional Rhenium doping is discovered by
means of high-resolution transmission electron microscopy. Using
density-functional calculations for the related MoS2 compound we consider a
possible origin of this phase transition, which was known formerly only for WS2
and MoS2 intercalated by alkali metals. An interplay between the stability of
layered or nanotubular forms of 2H and 1T allotropes is found to be intimately
related with their electronic structures and electro-donating ability of an
impurity.
Chinese: 通过高分辨率透射电子显微镜，发现了在替位铼掺杂下，多壁WS2纳米管中部分2H→1T相变的这种现象。利用相关MoS2化合物的密度泛函计算，我们考虑了这种相变可能的原因，以前只知道这种相变只存在于WS2和由碱金属嵌套的MoS2中。发现2H和1T同素异形体层状或纳米管形式的稳定性与它们的电子结构和杂质的电给电子能力密切相关。
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English: We investigate the circumstances under which cosmic inflation can arise from
very inhomogeneous initial conditions using numerical relativity simulations.
Previous studies have not considered cases with non-zero momentum density due
to technical challenges with solving the coupled Einstein constraint equations.
Here we address these, introducing and comparing several different ways of
constructing cosmological initial conditions with inhomogeneous scalar field
and time derivative profiles. We evolve such initial conditions with large
inhomogeneities in both single- and two-field inflationary models. We study
cases where the initial gradient and kinetic energy are much larger than the
inflationary energy scale, and black holes can form, as well as cases where the
initial scalar potential energy is comparable, as in scenarios where inflation
occurs at nearly Planckian densities, finding large-field inflation to be
generally robust. We consider examples of initial conditions where a large
scalar field velocity towards non-inflationary values would prevent inflation
from occurring in the homogeneous case, finding that the addition of large
gradients in the scalar field can actually dilute this effect, with the
increased expansion and non-vanishing restoring force leading to inflation.
Chinese: 我们利用数值相对论模拟研究宇宙暴胀能否从非常不均匀的初始条件下产生。以往的研究尚未考虑具有非零动量密度的情形，因为解决耦合爱因斯坦约束方程存在技术挑战。在此我们解决了这些问题，引入并比较了几种不同的方法来构建具有不均匀标量场和时间导数轮廓的宇宙学初始条件。我们在单场和双场暴胀模型中演化这些初始条件，其中存在较大的不均匀性。我们研究了初始梯度与动能远大于暴胀能量尺度的情形，此时黑洞可以形成，以及初始标量势能与之相当的情形，例如在接近普朗克密度的暴胀场景中，发现大场暴胀通常是稳健的。我们考虑了初始条件中的标量场速度向非暴胀值快速变化的例子，在均匀情况下这会阻止暴胀发生，发现标量场中添加较大的梯度实际上可以减弱这种效应，随着膨胀的加剧和非消失的恢复力作用，最终导致暴胀发生。
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English: We review the numerical analysis' understanding of Krylov subspace methods
for solving (non-hermitian) systems of equations and discuss its implications
for lattice gauge theory computations using the example of the Wilson fermion
matrix. Our thesis is that mature methods like QMR, BiCGStab or restarted GMRES
are close to optimal for the Wilson fermion matrix. Consequently,
preconditioning appears to be the crucial issue for further improvements.
Chinese: 我们回顾了数值分析对Krylov子空间方法在求解（非厄米）方程组方面的理解，并讨论了其在使用Wilson费米子矩阵为例的晶格规范场理论计算中的影响。我们的论点是，成熟的方法如QMR、BiCGStab或重启的GMRES对于Wilson费米子矩阵来说几乎是最优的。因此，预条件似乎对于进一步的改进是关键问题。
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English: Instruction-following made modern large language models (LLMs) helpful
assistants. However, the key to taming LLMs on complex instructions remains
mysterious, for that there are huge gaps between models trained by open-source
community and those trained by leading companies. To bridge the gap, we propose
a simple and scalable approach UltraIF for building LLMs that can follow
complex instructions with open-source data. UltraIF first decomposes real-world
user prompts into simpler queries, constraints, and corresponding evaluation
questions for the constraints. Then, we train an UltraComposer to compose
constraint-associated prompts with evaluation questions. This prompt composer
allows us to synthesize complicated instructions as well as filter responses
with evaluation questions. In our experiment, for the first time, we
successfully align LLaMA-3.1-8B-Base to catch up with its instruct version on 5
instruction-following benchmarks without any benchmark information, using only
8B model as response generator and evaluator. The aligned model also achieved
competitive scores on other benchmarks. Moreover, we also show that UltraIF
could further improve LLaMA-3.1-8B-Instruct through self-alignment, motivating
broader use cases for the method. Our code will be available at
https://github.com/kkk-an/UltraIF.
Chinese: 遵循指令使现代大型语言模型（LLMs）成为有用的助手。然而，在复杂指令上驯化LLMs的关键仍然是个谜，因为开源社区训练的模型与领先公司训练的模型之间存在巨大差距。为弥合这一差距，我们提出了一种简单且可扩展的方法UltraIF，用于构建能够使用开源数据遵循复杂指令的LLMs。UltraIF首先将现实世界的用户提示分解为更简单的查询、约束以及相应的约束评估问题。然后，我们训练一个UltraComposer来组合与约束相关的提示和评估问题。这个提示组合器使我们能够合成复杂的指令，并能用评估问题过滤响应。在我们的实验中，我们首次成功地将LLaMA-3.1-8B-Base与它的指令版本在5个指令遵循基准上对齐，且无需任何基准信息，仅使用8B模型作为响应生成器和评估器。对齐后的模型在其他基准上也取得了有竞争力的分数。此外，我们还展示了UltraIF可以通过自我对齐进一步提升LLaMA-3.1-8B-Instruct的性能，这为该方法开辟了更广泛的应用场景。我们的代码将在https://github.com/kkk-an/UltraIF上公开。
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English: Hyperdimensional computing (HDC) is an increasingly popular computing
paradigm with immense potential for future intelligent applications. Although
the main ideas already took form in the 1990s, HDC recently gained significant
attention, especially in the field of machine learning and data science. Next
to efficiency, interoperability and explainability, HDC offers attractive
properties for generalization as it can be seen as an attempt to combine
connectionist ideas from neural networks with symbolic aspects. In recent work,
we introduced the hyperdimensional transform, revealing deep theoretical
foundations for representing functions and distributions as high-dimensional
holographic vectors. Here, we present the power of the hyperdimensional
transform to a broad data science audience. We use the hyperdimensional
transform as a theoretical basis and provide insight into state-of-the-art HDC
approaches for machine learning. We show how existing algorithms can be
modified and how this transform can lead to a novel, well-founded toolbox. Next
to the standard regression and classification tasks of machine learning, our
discussion includes various aspects of statistical modelling, such as
representation, learning and deconvolving distributions, sampling, Bayesian
inference, and uncertainty estimation.
Chinese: 超维计算（HDC）是一种越来越受欢迎的计算范式，具有巨大潜力应用于未来的智能应用。尽管其主要思想在20世纪90年代就已经成形，但HDC最近引起了显著的关注，尤其是在机器学习和数据科学领域。除了效率之外，HDC还提供了互操作性和可解释性等吸引人的特性，因为它可以被视为将神经网络中的连接主义思想与符号方面相结合的尝试。在最近的研究中，我们引入了超维变换，揭示了将函数和分布表示为高维全息向量的深刻理论基础。在这里，我们向广大的数据科学听众展示了超维变换的力量。我们将超维变换作为理论基础，并提供了对最先进的HDC机器学习方法的见解。我们展示了如何修改现有算法，以及这种变换如何导致一个新颖且稳固的工具箱。除了机器学习的标准回归和分类任务之外，我们的讨论还包括统计建模的各个方面，如表示、学习、反卷积分布、采样、贝叶斯推理和不确定性估计。
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English: In recent work by M.H.Lynch, E.Cohen, Y.Hadad and I.Kaminer (LCHK), a
modified model of the Unruh-DeWitt quantum detector, coupled to a 4-vector
current, has been proposed to examine the radiation emitted by high energy
positrons channeled into silicon crystal samples. Inspired by their ideas, we
analyze theoretical aspects of such a model, its internal consistency, and
ignore all questions related to experiments. The two-potential correlation
functions for the quantized electromagnetic field in a vacuum state and the
corresponding detector radiation power (DRP), considered in proper time
formalism, are used as the basis for investigating the radiation observed at an
accelerating point detector. The quantum detector is assumed to be moving
through an electromagnetic vacuum along a classical hyperbolic trajectory with
a constant proper acceleration. The DRP is obtained for three possible cases.
First, the DRP is found in a Lorentz-invariant manner. It contains both
transverse and non-physical longitudinal polarization modes and is a divergent
quantity. Second, the radiation power holds only physical transverse modes but
it is non-relativistic and also depends on the detector proper time, which
contradicts the fact that there is no preferred time for hyperbolic detector
motion. Third, in the case considered by LCHK, for zero detector proper time
when its velocity in the lab inertial system is zero, the radiation power with
transverse modes shows some signs of thermality which could be associated with
a detector acceleration but different from the Bose-Einstein statistics
expected for the photon field. If the detector energy gap is zero then, in
complete contradiction with what LCHK claim, there is no radiation and no
"thermalized Larmor formula". Based on our analysis we do not believe that the
LCHK's model can be used to support the idea about thermal effects of uniform
acceleration.
Chinese: 在M.H.Lynch、E.Cohen、Y.Hadad和I.Kaminer（LCHK）最近的研究工作中，提出了一种修改后的Unruh-DeWitt量子探测器模型，该模型与一个四矢量电流耦合，用于检验高能正电子被导向硅晶体样品时发出的辐射。受他们想法的启发，我们分析了此类模型的理论方面、其内部一致性，并忽略了所有与实验相关的问题。在适当时间形式主义中，我们使用真空状态下量子电磁场的双势相关函数以及相应的探测器辐射功率（DRP）作为研究加速点探测器观察到的辐射的基础。假设量子探测器沿着具有恒定固有加速度的经典双曲轨迹在电磁真空中移动。对于三种可能的情况，得到了DRP。首先，DRP以洛伦兹不变的方式被发现。它包含横向和非物理纵向偏振模式，是一个发散量。其次，辐射功率只包含物理横向模式，但它是非相对论的，并且依赖于探测器的固有时间，这与超曲探测器运动没有首选时间的事实相矛盾。第三，在LCHK考虑的情况下，当探测器的实验室惯性系中的速度为零时，其固有时间为零，具有横向模式的辐射功率显示出一些与热力学相关的迹象，这可能与探测器加速有关，但与光子场预期的玻色-爱因斯坦统计不同。如果探测器能隙为零，那么与LCHK声称的完全相反，没有辐射，也没有“热化的拉莫公式”。基于我们的分析，我们不相信LCHK的模型可以用来支持关于均匀加速热效应的想法。
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English: Training deep recurrent neural network (RNN) architectures is complicated due
to the increased network complexity. This disrupts the learning of higher order
abstracts using deep RNN. In case of feed-forward networks training deep
structures is simple and faster while learning long-term temporal information
is not possible. In this paper we propose a residual memory neural network
(RMN) architecture to model short-time dependencies using deep feed-forward
layers having residual and time delayed connections. The residual connection
paves way to construct deeper networks by enabling unhindered flow of gradients
and the time delay units capture temporal information with shared weights. The
number of layers in RMN signifies both the hierarchical processing depth and
temporal depth. The computational complexity in training RMN is significantly
less when compared to deep recurrent networks. RMN is further extended as
bi-directional RMN (BRMN) to capture both past and future information.
Experimental analysis is done on AMI corpus to substantiate the capability of
RMN in learning long-term information and hierarchical information. Recognition
performance of RMN trained with 300 hours of Switchboard corpus is compared
with various state-of-the-art LVCSR systems. The results indicate that RMN and
BRMN gains 6 % and 3.8 % relative improvement over LSTM and BLSTM networks.
Chinese: 由于网络复杂度的增加，训练深度循环神经网络（RNN）架构是复杂的。这干扰了使用深度RNN学习高阶抽象。在正向传播网络的情况下，训练深度结构简单且更快，但无法学习长期时间信息。在这篇论文中，我们提出了一种残差记忆神经网络（RMN）架构，使用具有残差和时延连接的深度前馈层来建模短期依赖关系。残差连接为构建更深层次的网络铺平了道路，因为它允许梯度无阻碍地流动，而时延单元通过共享权重捕获时间信息。RMN中的层数既表示层次处理深度，也表示时间深度。与深度循环网络相比，在训练RMN时的计算复杂度显著降低。RMN进一步扩展为双向RMN（BRMN），以捕获过去和未来的信息。在AMI语料库上进行了实验分析，以证实RMN在学习和长期信息以及层次信息方面的能力。使用300小时的Switchboard语料库训练的RMN的识别性能与各种最先进的LVCSR系统进行了比较。结果表明，RMN和BRMN相对于LSTM和BLSTM网络分别提高了6%和3.8%的相对性能。
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English: Acoustic bianisotropic materials couple pressure and local particle velocity
fields to simultaneously excite monopole and dipole scattering, which results
in asymmetric wave transmission and reflection of airborne sound. In this work,
we systematically realize an arbitrarily given bianisotropic coupling between
the pressure and velocity fields for asymmetric wave propagation by an acoustic
grating with inversion symmetry breaking. This acoustic bianisotropic grating
is designed by optimizing the unit cells with a finite element method to
achieve the desired scattering wavevectors determined by the bianisotropic
induced asymmetric wave propagation. The symmetry and Bloch wavevectors in the
reciprocal space resulted from the grating are analyzed, which match with the
desired scattering wavevectors. The designed structures are fabricated for the
experimental demonstration of the bianisotropic properties. The measured
results match with the desired asymmetric wave scattering fields.
Chinese: 声学各向异性材料将压力和局部粒子速度场耦合，以同时激发单极子和偶极子散射，这导致空气声波的不对称传播和反射。在本工作中，我们通过具有反演对称破缺的声学光栅，系统地实现了压力场和速度场之间任意给定的各向异性耦合，以实现不对称波传播。该声学各向异性光栅通过有限元方法优化单元细胞设计，以实现由各向异性引起的非对称波传播所决定的所需散射波矢量。分析了由光栅产生的倒空间中的对称性和布洛赫波矢量，它们与所需的散射波矢量相匹配。为实验演示各向异性特性，设计了相应的结构。测量的结果与所需的不对称波散射场相匹配。
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English: The integration of network information and node attribute information has
recently gained significant attention in the community detection literature. In
this work, we consider community detection in the Contextual Labeled Stochastic
Block Model (CLSBM), where the network follows an LSBM and node attributes
follow a Gaussian Mixture Model (GMM). Our primary focus is the
misclassification rate, which measures the expected number of nodes
misclassified by community detection algorithms. We first establish a lower
bound on the optimal misclassification rate that holds for any algorithm. When
we specialize our setting to the LSBM (which preserves only network
information) or the GMM (which preserves only node attribute information), our
lower bound recovers prior results. Moreover, we present an efficient
spectral-based algorithm tailored for the CLSBM and derive an upper bound on
its misclassification rate. Although the algorithm does not attain the lower
bound, it serves as a reliable starting point for designing more accurate
community detection algorithms (as many algorithms use spectral method as an
initial step, followed by refinement procedures to enhance accuracy).
Chinese: 网络信息与节点属性信息的融合近年来在社区检测领域引起了广泛关注。在本工作中，我们考虑上下文标记随机块模型（Contextual Labeled Stochastic Block Model, CLSBM）下的社区检测，其中网络遵循随机块模型（Randomized Block Model, LSBM），节点属性遵循高斯混合模型（Gaussian Mixture Model, GMM）。我们的主要关注点是误分类率，该指标衡量社区检测算法误分类节点的期望数量。我们首先针对任意算法建立了最优误分类率的下界。当我们将设置特殊化为仅保留网络信息的LSBM或仅保留节点属性信息的GMM时，我们的下界结果与已有研究一致。此外，我们提出了一种针对CLSBM的高效谱方法算法，并对其误分类率推导了上界。尽管该算法未达到下界，但可作为设计更精确社区检测算法的可靠起点（许多算法将谱方法作为初始步骤，随后通过精炼过程提升精度）。
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English: Due to the increasing use of Machine Learning models in high stakes decision
making settings, it has become increasingly important to have tools to
understand how models arrive at decisions. Assuming a trained Supervised
Classification model, explanations can be obtained via counterfactual analysis:
a counterfactual explanation of an instance indicates how this instance should
be minimally modified so that the perturbed instance is classified in the
desired class by the Machine Learning classification model. Most of the
Counterfactual Analysis literature focuses on the single-instance
single-counterfactual setting, in which the analysis is done for one single
instance to provide one single explanation. Taking a stakeholder's perspective,
in this paper we introduce the so-called collective counterfactual
explanations. By means of novel Mathematical Optimization models, we provide a
counterfactual explanation for each instance in a group of interest, so that
the total cost of the perturbations is minimized under some linking
constraints. Making the process of constructing counterfactuals collective
instead of individual enables us to detect the features that are critical to
the entire dataset to have the individuals classified in the desired class. Our
methodology allows for some instances to be treated individually, performing
the collective counterfactual analysis for a fraction of records of the group
of interest. This way, outliers are identified and handled appropriately. Under
some assumptions on the classifier and the space in which counterfactuals are
sought, finding collective counterfactuals is reduced to solving a convex
quadratic linearly constrained mixed integer optimization problem, which, for
datasets of moderate size, can be solved to optimality using existing solvers.
The performance of our approach is illustrated on real-world datasets,
demonstrating its usefulness.
Chinese: 由于机器学习模型在高风险决策环境中的使用日益增多，理解模型如何做出决策的工具变得愈发重要。假设有一个训练好的监督分类模型，可以通过反事实分析获得解释：一个实例的反事实解释表明，为了使扰动后的实例被机器学习分类模型分类到期望的类别，该实例应进行的最小修改。大多数反事实分析文献集中于单实例单反事实的设置，即针对单个实例进行分析以提供单一解释。从利益相关者的角度来看，在本文中，我们引入了所谓的集体反事实解释。通过新颖的数学优化模型，我们为感兴趣群体中的每个实例提供反事实解释，从而在满足某些关联约束的条件下最小化扰动总成本。将构建反事实的过程从个体变为集体，使我们能够检测对整个数据集而言对个体分类至关重要的特征。我们的方法论允许某些实例单独处理，对感兴趣群体的一部分记录进行集体反事实分析。这样，异常值被识别并得到适当处理。在一些关于分类器和反事实搜索空间的假设下，寻找集体反事实被简化为求解一个凸二次线性约束混合整数优化问题，对于中等规模的数据集，可以使用现有求解器以最优解求解。
我们的方法在真实世界数据集上的性能得到了验证，证明了其有效性。
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English: We investigate the challenging problem of integrating detection, signal
processing, target tracking, and adaptive waveform scheduling with lookahead in
urban terrain. We propose a closed-loop active sensing system to address this
problem by exploiting three distinct levels of diversity: (1) spatial diversity
through the use of coordinated multistatic radars; (2) waveform diversity by
adaptively scheduling the transmitted waveform; and (3) motion model diversity
by using a bank of parallel filters matched to different motion models.
Specifically, at every radar scan, the waveform that yields the minimum trace
of the one-step-ahead error covariance matrix is transmitted; the received
signal goes through a matched-filter, and curve fitting is used to extract
range and range-rate measurements that feed the LMIPDA-VSIMM algorithm for data
association and filtering. Monte Carlo simulations demonstrate the
effectiveness of the proposed system in an urban scenario contaminated by dense
and uneven clutter, strong multipath, and limited line-of-sight.
Chinese: 我们研究了在城市地形中整合检测、信号处理、目标跟踪和具有前瞻性的自适应波形调度这一具有挑战性的问题。我们提出了一种闭环主动感知系统来解决这个问题，该系统利用了三个不同的多样性层次：(1) 通过使用协同多基地雷达实现空间多样性；(2) 通过自适应调度发射波形实现波形多样性；(3) 通过使用匹配到不同运动模型的并行滤波器组实现运动模型多样性。具体而言，在每次雷达扫描时，会发射能够产生最小一步前向误差协方差矩阵迹的波形；接收到的信号会通过匹配滤波器处理，并使用曲线拟合提取距离和距离速率测量值，这些测量值将输入LMIPDA-VSIMM算法进行数据关联和滤波。蒙特卡洛仿真表明，所提出的系统在存在密集且不均匀杂波、强多径和视距受限的城市场景中是有效的。
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English: The transient processes of a turbulent large-scale convective circulation
(LSC) in a cubic cell are investigated using large-eddy simulations for
Rayleigh number $\Ray=10^8$ and Prandtl number $\Pran=0.7$. For the first time,
we have explicitly shown that LSC is accompanied by large-scale azimuthal flows
with non-zero total angular momentum. It is also shown that solid-body rotation
of the entire fluid is not realized. It is found that correlation between
rotation of LSC plane and the mean azimuthal motion is high during
quasiperiodic oscillations of LSC near the diagonal plane and relatively weak
during LSC reorientations. We propose a new plausible scenario for the
reorientations of the LSC in a cube that does not involve a mean azimuthal
flow. Instead of a single-roll, we introduce the superposition of a pair of
large-scale orthogonal quasi-two-dimensional (Q2D) rolls and the reorientation
of the LSC occurs as a result of the cessation of one of the Q2D rolls. This
scenario is consistent with all known experimental and numerical data.
Chinese: 使用大涡模拟对立方体单元中湍流大规模对流环流（LSC）的瞬态过程进行研究，雷诺数 $\Ray=10^8$ 和普朗特数 $\Pran=0.7$。首次明确地表明，LSC伴随着具有非零总角动量的大规模径向流动。还表明，整个流体的刚体旋转并未实现。发现在LSC接近对角平面附近的准周期振荡期间，LSC平面的旋转与平均径向运动之间的相关性很高，而在LSC重新定向期间则相对较弱。我们提出了一种新的、可能的场景，用于解释立方体中LSC的重新定向，该场景不涉及平均径向流动。我们不是引入单一的滚动，而是引入一对大规模正交准二维（Q2D）滚动的叠加，LSC的重新定向是由于其中一对Q2D滚动停止的结果。这一场景与所有已知的实验和数值数据一致。
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English: Models for the transport of high energy charged particles through strong
magnetic turbulence play a key role in space and astrophysical studies, such as
describing the propagation of solar energetic particles and high energy cosmic
rays. Inspired by the recent advances in high-performance machine learning
techniques, we investigate the application of generative diffusion models to
synthesizing test particle trajectories obtained from a turbulent
magnetohydrodynamics simulation. We consider velocity increment, spatial
transport and curvature statistics, and find excellent agreement with the
baseline trajectories for fixed particle energies. Additionally, we consider
two synthetic turbulence models for comparison. Finally, challenges towards an
application-ready transport model based on our approach are discussed.
Chinese: 通过强磁场湍流传输高能带电粒子的模型在空间和天体物理学研究中起着关键作用，例如描述太阳高能粒子和高能宇宙射线的传播。受到高性能机器学习技术近期进展的启发，我们研究了生成扩散模型在合成从湍流磁流体动力学模拟中获得测试粒子轨迹中的应用。我们考虑速度增量、空间传输和曲率统计，并发现与固定粒子能量的基线轨迹有极好的吻合。此外，我们还考虑了两种合成湍流模型进行比较。最后，讨论了我们方法在实际应用中面临的挑战。
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English: Supersingular elliptic curve $\ell$-isogeny graphs over finite fields offer a
setting for a number of quantum-resistant cryptographic protocols. The security
analysis of these schemes typically assumes that these graphs behave randomly.
Motivated by this debatable assertion, we explore structural properties of
these graphs. We detail the behavior, governed by congruence conditions on $p$,
of the $\ell$-isogeny graph over $\mathbb{F}_p$ when passing to the spine,
i.e.\ the subgraph induced by the $\mathbb{F}_p$-vertices in the full
$\ell$-isogeny graph. We describe the diameter of the spine and offer numerical
data on the number of vertices, over both $\mathbb{F}_p$ and
$\overline{\mathbb{F}}_p$, in the center of the $\ell$-isogeny graph. Our plots
of these counts exhibit an intriguing wave-shaped pattern which warrants
further investigation. Accompanying code:
https://github.com/TahaHedayat/LUCANT-2025-Supersingular-Ell-Isogeny-Spine
Chinese: 有限域上的超奇异椭圆曲线 $\ell$-同构图为多种抗量子密码协议提供了一个环境。这些方案的安全分析通常假设这些图的行为是随机的。受这一有争议的断言的启发，我们探索了这些图的结构性质。我们详细描述了当过渡到骨架时，即由 $\mathbb{F}_p$-顶点在完整 $\ell$-同构图中诱导的子图，$\mathbb{F}_p$ 上的 $\ell$-同构图的行为，这受到 $p$ 的同余条件控制。我们描述了骨架的直径，并提供了关于 $\ell$-同构图中心的顶点数（在 $\mathbb{F}_p$ 和 $\overline{\mathbb{F}}_p$ 上）的数值数据。我们这些计数量的图表显示出一种有趣的波形模式，这值得进一步研究。伴随的代码：
https://github.com/TahaHedayat/LUCANT-2025-Supersingular-Ell-Isogeny-Spine
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English: Self-interacting dark matter (SIDM), through gravothermal evolution driven by
elastic self-scatterings, offers a compelling explanation for the observed
diversity of inner halo densities. In this work, we investigate SIDM dynamics
in a two-component dark matter model with mass ratios of order unity, motivated
by an asymmetric dark matter framework that naturally evades constraints from
relic abundance and mediator decay, while enabling strong, velocity-dependent
self-interactions. We show that cross-component scatterings significantly
enhance mass segregation, driving the formation of dense, core collapsed-like
halos. This effect couples naturally to SIDM-induced diversity, introducing a
new mechanism for generating structural variations beyond those arising from
gravothermal evolution alone. Our results reveal a novel mechanism for
reconciling SIDM with small-scale observational tensions by enabling shifts in
central densities while preserving the flexibility to generate diverse halo
structures. We further highlight that halo structural diversity may serve as a
diagnostic of dark sector composition, opening a new observational window into
the particle nature of SIDM.
Chinese: 自相互作用暗物质（SIDM），通过弹性自散射驱动的热力学演化，为观测到的内晕密度多样性提供了一个有力的解释。在这项工作中，我们研究了一个具有相同量级质量比的两成分暗物质模型中的SIDM动力学，这一模型受到非对称暗物质框架的启发，该框架自然规避了来自遗迹丰度和介子衰变的限制，同时实现了强、速度依赖的自相互作用。我们表明，跨成分散射显著增强了质量分离，驱动了密集、核心塌缩状晕的形成。这一效应自然地与SIDM引起的多样性相结合，引入了一种新的机制，用于产生仅由热力学演化引起的结构变化之外的结构变化。我们的结果表明，通过允许中心密度的变化同时保持生成多样晕结构的灵活性，可以解决SIDM与小型观测紧张之间的矛盾。我们进一步强调，晕结构多样性可能作为暗物质组成的一个诊断工具，为SIDM的粒子性质打开一个新的观测窗口。
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English: We consider sound waves in superfluid nucleon-hyperon matter of massive
neutron-star cores. We calculate and analyze the speeds of sound modes and
their damping times due to the shear viscosity and non-equilibrium weak
processes of particle transformations. For that, we employ the dissipative
relativistic hydrodynamics of a superfluid nucleon-hyperon mixture, formulated
recently [M.E. Gusakov and E.M. Kantor, Phys. Rev. D78, 083006 (2008)]. We
demonstrate that the damping times of sound modes calculated using this
hydrodynamics and the ordinary (nonsuperfluid) one, can differ from each other
by several orders of magnitude.
Chinese: 我们考虑了质量中子星核心中超流体核子-超子物质的声波。我们计算并分析了声模的速度及其由于剪切粘滞和非平衡弱过程引起的粒子变换的阻尼时间。为此，我们采用了超流体核子-超子混合物的耗散相对流体动力学，该动力学最近由[M.E. Gusakov和E.M. Kantor，物理评论D78，083006（2008）]提出。我们证明了使用这种流体动力学和普通（非超流体）流体动力学计算出的声模阻尼时间可以相差几个数量级。
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English: Explanations for description logic (DL) entailments provide important support
for the maintenance of large ontologies. The "justifications" usually employed
for this purpose in ontology editors pinpoint the parts of the ontology
responsible for a given entailment. Proofs for entailments make the
intermediate reasoning steps explicit, and thus explain how a consequence can
actually be derived. We present an interactive system for exploring description
logic proofs, called Evonne, which visualizes proofs of consequences for
ontologies written in expressive DLs. We describe the methods used for
computing those proofs, together with a feature called signature-based proof
condensation. Moreover, we evaluate the quality of generated proofs using real
ontologies.
Chinese: 对于描述逻辑（DL）推理的解释为大型本体库的维护提供了重要的支持。在用于此目的的本体编辑器中通常采用的“理由”能够指出导致特定推理结果的本体部分。推理的证明将中间推理步骤显式化，从而解释了如何实际得出某个结论。我们介绍了一个用于探索描述逻辑证明的交互式系统，名为Evonne，它能够可视化用表达能力较强的DL编写的本体中后果的证明。我们描述了用于计算这些证明的方法，以及一个名为基于签名的证明压缩的特性。此外，我们利用真实本体评估生成的证明的质量。
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English: Bohmian mechanics was designed to give rise to predictions identical to those
derived by standard quantum mechanics, while invoking a specific interpretation
of it - one which allows the classical notion of a particle to be maintained
alongside a guiding wave. For this, the Bohmian model makes use of a unique
quantum potential which governs the trajectory of the particle. In this work we
show that this interpretation of quantum theory naturally leads to the
derivation of interesting new phenomena. Specifically, we demonstrate how the
fundamental Casimir-Polder force, by which atoms are attracted to a surface,
may be temporarily suppressed by utilizing a specially designed quantum
potential. We show that when harnessing the quantum potential via a suitable
atomic wavepacket engineering, the absorption by the surface can be
dramatically reduced. This is proven both analytically and numerically.
Finally, an experimental scheme is proposed for achieving the required shape
for the atomic wavepacket. All these may enable new insights into Bohmian
mechanics as well as new applications to metrology and sensing.
Chinese: 玻姆力学旨在产生与标准量子力学推导出的预测相同的预测，同时采用对其特定的解释——一种允许在引导波的同时维持经典粒子的概念。为此，玻姆模型利用了一种独特的量子势，它控制着粒子的轨迹。在这项工作中，我们展示了这种量子理论的解释自然地导致有趣的新现象的推导。具体来说，我们演示了通过利用专门设计的量子势，原子被表面吸引的基本卡西米尔-波尔德力可能暂时被抑制。我们表明，通过合适的原子波包工程利用量子势，表面的吸收可以显著降低。这一点既通过分析也通过数值得到了证明。最后，提出了一种实验方案，以实现所需的原子波包形状。所有这些可能使我们对玻姆力学有新的认识，以及将其应用于计量学和传感的新应用。
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English: Semiprime ideals of an arbitrary Leavitt path algebra L are described in
terms of their generators. This description is then used to show that the
semiprime ideals form a complete sublattice of the lattice of ideals of L, and
they enjoy a certain gap property identified by Kaplansky in prime spectra of
commutative rings. It is also shown that the totally ordered sets that can be
realized as prime spectra of Leavitt path algebras are precisely those that
have greatest lower bounds on subchains and enjoy the aforementioned gap
property. Finally, it is shown that a conjecture of Kaplansky regarding
identifying von Neumann regular rings via their prime factors holds for Leavitt
path algebras.
Chinese: 任意Leavitt路径代数L的半素理想可以用它们的生成元来描述。然后，利用这种描述来证明半素理想构成了L的理想格的一个完备子格，并且它们具有Kaplansky在交换环的素谱中识别出的某种间隙性质。还证明了可以实化为Leavitt路径代数素谱的完全有序集恰好是那些在子链上具有最大下界的集合，并享有上述间隙性质。最后，证明了Kaplansky关于通过素因子识别冯·诺伊曼正规环的猜想对于Leavitt路径代数是成立的。
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English: We present the findings of the superconductivity observed in the silicon
nanostructures prepared by short time diffusion of boron on the n-type Si(100)
surface. These Si-based nanostructures represent the p-type ultra-narrow
self-assembled silicon quantum wells, 2nm, confined by the delta - barriers
heavily doped with boron, 3nm. The EPR and the thermo-emf studies show that the
delta - barriers appear to consist of the trigonal dipole centres, which are
caused by the negative-U reconstruction of the shallow boron acceptors. Using
the CV and thermo-emf techniques, the transport of two-dimensional holes inside
SQW is demonstrated to be accompanied by single-hole tunneling through these
negative-U centres that results in the superconductivity of the delta -
barriers. The values of the correlation gaps obtained from these measurements
are in a good agreement with the data derived from the temperature and magnetic
field dependencies of the magnetic susceptibility, which reveal a strong
diamagnetism and additionally identify the superconductor gap value.
Chinese: 我们展示了在n型Si(100)表面通过短时间硼扩散制备的硅纳米结构中观察到的超导性研究结果。这些基于硅的纳米结构代表了p型超窄自组装硅量子阱，尺寸为2nm，由重掺杂硼的δ-势垒（3nm）所限制。EPR和热电动势研究表明，δ-势垒似乎由三角双极中心组成，这是由浅硼受体的负-U重构引起的。利用循环伏安法和热电动势技术，证明了二维空穴在SQW中的传输伴随着通过这些负-U中心的单空穴隧穿，从而导致了δ-势垒的超导性。从这些测量中获得的关联能隙值与从磁化率的温度和磁场依赖性数据中得出的数据相吻合，这些数据揭示了强烈的抗磁性，并进一步确定了超导能隙值。
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English: The majority of existing results for the kilonova (or macronova) emission
from material ejected during a neutron-star (NS) merger is based on
(quasi-)one-zone models or manually constructed toy-model ejecta
configurations. In this study we present a kilonova analysis of the material
ejected during the first ~10ms of a NS merger, called dynamical ejecta, using
directly the outflow trajectories from general relativistic smoothed-particle
hydrodynamics simulations including a sophisticated neutrino treatment and the
corresponding nucleosynthesis results, which have been presented in Part I of
this study. We employ a multi-dimensional two-moment radiation transport scheme
with approximate M1 closure to evolve the photon field and use a heuristic
prescription for the opacities found by calibration with atomic-physics based
reference results. We find that the photosphere is generically ellipsoidal but
augmented with small-scale structure and produces emission that is about 1.5-3
times stronger towards the pole than the equator. The kilonova typically peaks
after 0.7-1.5days in the near-infrared frequency regime with luminosities
between 3-7x10^40erg/s and at photospheric temperatures of 2.2-2.8x10^3K. A
softer equation of state or higher binary-mass asymmetry leads to a longer and
brighter signal. Significant variations of the light curve are also obtained
for models with artificially modified electron fractions, emphasizing the
importance of a reliable neutrino-transport modeling. None of the models
investigated here, which only consider dynamical ejecta, produces a transient
as bright as AT2017gfo. The near-infrared peak of our models is incompatible
with the early blue component of AT2017gfo.
Chinese: 现有关于中子星合并（或宏观新星）过程中抛射物质发射的千新星（或宏观新星）结果，主要基于（准）单区模型或手动构建的玩具模型抛射物质配置。在这项研究中，我们通过直接使用广义相对论平滑粒子流体动力学模拟中包含精细化中微子处理和相应核合成结果的流出轨迹，对中子星合并初期约10毫秒抛射的物质（称为动力学抛射物质）进行了千新星分析。这些模拟和核合成的结果在本篇研究的第一部分中已有介绍。我们采用多维两矩辐射传输方案，结合近似M1闭合近似，来演化光子场，并使用通过与基于原子物理学的参考结果校准得到的半经验式透明度处方。我们发现，照片球通常是椭球形的，但带有小规模结构，并且其发射的光度在极点方向比赤道方向强约1.5-3倍。千新星通常在近红外频率范围内于0.7-1.5天后达到峰值，光度在3-7×10^40 erg/s之间，照片球温度为2.2-2.8×10^3 K。较软的方程状态或更高的二进制质量不对称性导致信号更长更亮。对于人工修改电子分数的模型，我们也得到了显著的光曲线变化，强调了可靠中微子传输建模的重要性。在这里研究的模型中，只有考虑了动力学抛射物质，均未能产生与AT2017gfo一样亮的瞬态。我们模型的近红外峰值与AT2017gfo的早期蓝色成分不符。
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English: We propose a new model of cluster growth according to which the probability
that a new unit is placed in a point at a distance $r$ from the city center is
a Gaussian with mean equal to the cluster radius and variance proportional to
the mean, modulated by the local density $\rho(r)$. The model is analytically
solvable in $d=2$ dimensions, where the density profile varies as a
complementary error function. The model reproduces experimental observations
relative to the morphology of cities, determined via an original analysis of
digital maps with a very high spatial resolution, and helps understanding the
emergence of vehicular traffic.
Chinese: 我们提出了一种新的集群增长模型，根据该模型，新单元放置在距离城市中心$r$处的概率服从高斯分布，其均值等于集群半径，方差与均值成正比，并通过局部密度$\rho(r)$进行调制。该模型在$d=2$维度的解析可解，其中密度分布随补余误差函数变化。该模型通过原始分析具有非常高空间分辨率的数字地图，再现了关于城市形态的实验观察结果，并有助于理解车辆交通的出现。
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English: We investigate the ground state of the two-dimensional Heisenberg
antiferromagnet on two Archimedean lattices, namely, the maple-leaf and bounce
lattices as well as a generalized $J$-$J'$ model interpolating between both
systems by varying $J'/J$ from $J'/J=0$ (bounce limit) to $J'/J=1$ (maple-leaf
limit) and beyond. We use the coupled cluster method to high orders of
approximation and also exact diagonalization of finite-sized lattices to
discuss the ground-state magnetic long-range order based on data for the
ground-state energy, the magnetic order parameter, the spin-spin correlation
functions as well as the pitch angle between neighboring spins. Our results
indicate that the "pure" bounce ($J'/J=0$) and maple-leaf ($J'/J=1$) Heisenberg
antiferromagnets are magnetically ordered, however, with a sublattice
magnetization drastically reduced by frustration and quantum fluctuations. We
found that magnetic long-range order is present in a wide parameter range $0
\le J'/J \lesssim J'_c/J $ and that the magnetic order parameter varies only
weakly with $J'/J$. At $J'_c \approx 1.45 J$ a direct first-order transition to
a quantum orthogonal-dimer singlet ground state without magnetic long-range
order takes place. The orthogonal-dimer state is the exact ground state in this
large-$J'$ regime, and so our model has similarities to the Shastry-Sutherland
model. Finally, we use the exact diagonalization to investigate the
magnetization curve. We a find a 1/3 magnetization plateau for $J'/J \gtrsim
1.07$ and another one at 2/3 of saturation emerging only at large $J'/J \gtrsim
3$.
Chinese: 我们研究了二维海森堡反铁磁体在两个阿基米德格子上的基态，即枫叶格子和弹跳格子，以及一个通过改变$J'/J$从$J'/J=0$（弹跳极限）到$J'/J=1$（枫叶极限）以及更远来在两个系统之间插值的一般$J$-$J'$模型。我们使用耦合簇方法进行高阶近似，并使用有限格子的精确对角化来讨论基于基态能量、磁序参量、自旋-自旋相关函数以及相邻自旋之间的倾角的基础上的基态磁长程序。我们的结果表明，“纯”弹跳（$J'/J=0$）和枫叶（$J'/J=1$）海森堡反铁磁体在磁学上是有序的，然而，由于反常和量子涨落，亚格子磁化急剧降低。我们发现，在广泛的参数范围$0 \le J'/J \lesssim J'_c/J$中存在磁长程序，并且磁序参量仅弱地随$J'/J$变化。在$J'_c \approx 1.45 J$时，发生直接的一阶相变到没有磁长程序的量子正交二体单态基态。正交二体态是此大-$J'$区域的精确基态，因此我们的模型与Shastri-Sutherland模型有相似之处。最后，我们使用精确对角化来研究磁化曲线。我们发现对于$J'/J \gtrsim 1.07$有一个1/3磁化平台，另一个在饱和度的2/3处出现，仅在大的$J'/J \gtrsim 3$时出现。
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English: In this paper, we propose a new algorithm combining the Douglas-Rachford (DR)
algorithm and the Frank-Wolfe algorithm, also known as the conditional gradient
(CondG) method, for solving the classic convex feasibility problem. Within the
algorithm, which will be named {\it Approximate Douglas-Rachford (ApDR)
algorithm}, the CondG method is used as a subroutine to compute feasible
inexact projections on the sets under consideration, and the ApDR iteration is
defined based on the DR iteration. The ApDR algorithm generates two sequences,
the main sequence, based on the DR iteration, and its corresponding shadow
sequence. When the intersection of the feasible sets is nonempty, the main
sequence converges to a fixed point of the usual DR operator, and the shadow
sequence converges to the solution set. We provide some numerical experiments
to illustrate the behaviour of the sequences produced by the proposed
algorithm.
Chinese: 在本文中，我们提出了一种结合Douglas-Rachford（DR）算法和Frank-Wolfe算法（也称为条件梯度（CondG）方法）的新算法，用于解决经典的凸可行性问题。在算法中，该算法将被命名为“近似Douglas-Rachford（ApDR）算法”，CondG方法被用作子程序来计算考虑集中的可行不精确投影，并且ApDR迭代基于DR迭代定义。ApDR算法生成两个序列，主序列基于DR迭代，以及其对应的影子序列。当可行集的交集非空时，主序列收敛到通常的DR算子的一个不动点，而影子序列收敛到解集。我们提供了一些数值实验来阐述由所提出算法产生的序列的行为。
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English: We study whether and how can we model a joint distribution $p(x,z)$ using two
conditional models $p(x|z)$ and $q(z|x)$ that form a cycle. This is motivated
by the observation that deep generative models, in addition to a likelihood
model $p(x|z)$, often also use an inference model $q(z|x)$ for extracting
representation, but they rely on a usually uninformative prior distribution
$p(z)$ to define a joint distribution, which may render problems like posterior
collapse and manifold mismatch. To explore the possibility to model a joint
distribution using only $p(x|z)$ and $q(z|x)$, we study their compatibility and
determinacy, corresponding to the existence and uniqueness of a joint
distribution whose conditional distributions coincide with them. We develop a
general theory for operable equivalence criteria for compatibility, and
sufficient conditions for determinacy. Based on the theory, we propose a novel
generative modeling framework CyGen that only uses the two cyclic conditional
models. We develop methods to achieve compatibility and determinacy, and to use
the conditional models to fit and generate data. With the prior constraint
removed, CyGen better fits data and captures more representative features,
supported by both synthetic and real-world experiments.
Chinese: 我们研究如何使用两个形成循环的联合分布 $p(x,z)$ 的条件模型 $p(x|z)$ 和 $q(z|x)$ 来建模。这一研究动机源于观察到深度生成模型，除了似然模型 $p(x|z)$ 外，通常还使用推理模型 $q(z|x)$ 来提取表示，但它们依赖于通常信息量不足的先验分布 $p(z)$ 来定义联合分布，这可能导致后验坍缩和流形不匹配等问题。为了探索仅使用 $p(x|z)$ 和 $q(z|x)$ 来建模联合分布的可能性，我们研究了它们的兼容性和确定性，即是否存在一个联合分布，其条件分布与它们相匹配，并且该联合分布的唯一性。我们发展了一般理论，用于兼容性的可操作性等价标准，以及确定性的充分条件。基于该理论，我们提出了一种新的生成建模框架 CyGen，该框架仅使用这两个循环条件模型。我们开发了实现兼容性和确定性的方法，并使用条件模型来拟合和生成数据。移除先验约束后，CyGen 更好地拟合数据并捕获更多代表性特征，这一结论得到了合成实验和真实世界实验的支持。
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English: This paper introduces a novel method for transmitting video data over noisy
wireless channels with high efficiency and controllability. The method
derivates from model division multiple access (MDMA) to extract common semantic
features from video frames. It also uses deep joint source-channel coding
(JSCC) as the main framework to establish communication links and deal with
channel noise. An entropy-based variable length coding scheme is developed to
adjust the data amount accurately and explicitly. We name our method as model
division video semantic communication (MDVSC). The main steps of our approach
are as follows: first, video frames are transformed into a latent space to
reduce computational complexity and redistribute data. Then, common features
and individual features are extracted, and variable length coding is applied to
further eliminate redundant semantic information under the communication
bandwidth constraint. We evaluate our method on standard video test sequences
and compare it with traditional wireless video coding methods. The results show
that MDVSC generally surpasses the conventional methods in terms of quality
metrics and has the capability to control code length precisely. Moreover,
additional experiments and ablation studies are conducted to demonstrate its
potential for various tasks.
Chinese: 本文介绍了一种在具有高效率和可控性的情况下，通过噪声无线信道传输视频数据的新方法。该方法源自模型划分多址接入（MDMA），用于从视频帧中提取共同语义特征。它还使用深度联合源-信道编码（JSCC）作为主要框架来建立通信链路并处理信道噪声。开发了一种基于熵的变长编码方案，以精确和明确地调整数据量。我们称我们的方法为模型划分视频语义通信（MDVSC）。我们方法的主要步骤如下：首先，将视频帧转换为潜在空间，以降低计算复杂性和重新分配数据。然后，提取共同特征和个体特征，并在通信带宽约束下应用变长编码，进一步消除冗余语义信息。我们在标准视频测试序列上评估了我们的方法，并将其与传统无线视频编码方法进行了比较。结果表明，MDVSC在质量指标方面通常优于传统方法，并且能够精确控制码长。此外，还进行了额外的实验和消融研究，以展示其在各种任务中的潜力。
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English: Resistive tactile sensing gloves have captured the interest of researchers
spanning diverse domains, such as robotics, healthcare, and human-computer
interaction. However, existing fabrication methods often require
labor-intensive assembly or costly equipment, limiting accessibility.
Leveraging flexible printed circuit board (FPCB) technology, we present an
automated pipeline for generating resistive tactile sensing glove design files
solely from a simple hand photo on legal-size paper, which can be readily
supplied to commercial board houses for manufacturing. Our method enables
cost-effective, accessible production at under \$130 per glove with sensor
assembly times under 15 minutes. Sensor performance was characterized under
varying pressure loads, and a preliminary user evaluation showcases four unique
automatically manufactured designs, evaluated for their reliability and
comfort.
Chinese: 电阻式触觉感应手套因其在机器人、医疗保健和人机交互等领域的应用吸引了研究者的注意。然而，现有的制造方法往往需要劳动密集型的组装或是昂贵的设备，这限制了其可获取性。利用柔性印刷电路板（FPCB）技术，我们提出了一种自动化管道，仅通过一张法律尺寸的手部照片即可生成电阻式触觉感应手套设计文件，这些文件可以轻松提供给商业板房用于生产。我们的方法使得每只手套的成本低于130美元，传感器组装时间不到15分钟。在变化的压载下对传感器性能进行了表征，初步的用户评价展示了四款独特的自动制造设计，这些设计被评估了它们的可靠性和舒适度。
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English: We propose a new model based on the deconvolutional networks and SAX
discretization to learn the representation for multivariate time series.
Deconvolutional networks fully exploit the advantage the powerful
expressiveness of deep neural networks in the manner of unsupervised learning.
We design a network structure specifically to capture the cross-channel
correlation with deconvolution, forcing the pooling operation to perform the
dimension reduction along each position in the individual channel.
Discretization based on Symbolic Aggregate Approximation is applied on the
feature vectors to further extract the bag of features. We show how this
representation and bag of features helps on classification. A full comparison
with the sequence distance based approach is provided to demonstrate the
effectiveness of our approach on the standard datasets. We further build the
Markov matrix from the discretized representation from the deconvolution to
visualize the time series as complex networks, which show more class-specific
statistical properties and clear structures with respect to different labels.
Chinese: 我们提出了一种基于去卷积网络和SAX离散化的新模型，用于学习多元时间序列的表示。去卷积网络充分利用了深度神经网络在无监督学习方式下的强大表达能力。我们设计了一种特定的网络结构，通过去卷积捕捉跨通道相关性，迫使池化操作在每个单独通道的位置上执行降维。基于符号聚合近似（Symbolic Aggregate Approximation）的离散化应用于特征向量，以进一步提取特征集合。我们展示了这种表示和特征集合如何有助于分类。我们还提供了一个与基于序列距离方法的全对比，以证明我们的方法在标准数据集上的有效性。此外，我们从去卷积的离散化表示中构建了马尔可夫矩阵，以将时间序列可视化成复杂网络，这些网络显示出与不同标签相关的更多类特定统计特性和清晰的结构。
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English: In this paper, we study first the relationship between Pommaret bases and
Hilbert series. Given a finite Pommaret basis, we derive new explicit formulas
for the Hilbert series and for the degree of the ideal generated by it which
exhibit more clearly the influence of each generator. Then we establish a new
dimension depending Bezout bound for the degree and use it to obtain a
dimension depending bound for the ideal membership problem.
Chinese: 在这篇论文中，我们首先研究了Pommaret基与希尔伯特级数之间的关系。给定一个有限的Pommaret基，我们推导出希尔伯特级数及其由它生成的理想度的新显式公式，这些公式更清楚地展示了每个生成式的影响。然后，我们建立了一个新的关于维度的Bezout界，并利用它来获得理想成员问题的维度相关界。
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English: Yoshikawa [Yo] conjectured that a certain set of moves on marked graph
diagrams generates the isotopy relation for surface links in ${\mathbb R}^4$,
and this was proved by Swenton [S] and Kearton and Kurlin [KK]. In this paper,
we find another proof of this fact for the case of 2-links (surface links with
spherical components). The proof involves a version of Roseman's theorem [R]
for branch-free broken surface diagrams of 2-links and a construction of marked
graphs from branch-free broken surface diagrams.
Chinese: 吉野川[Yo]猜测在标记图示上进行特定的一系列操作可以生成${\mathbb R}^4$中表面链接的等距关系，这一猜测由Swenton [S]和Kearton与Kurlin [KK]证明。在本文中，我们为2-链接（具有球面组件的表面链接）的情况找到了这一事实的另一种证明。证明涉及对2-链接的分支自由断裂表面图的Roseman定理[R]的一个版本，以及从分支自由断裂表面图构造标记图的方法。
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English: We study homological mirror symmetry of the singular hypersurface
$X_0=V(t^{n+1}-x_0\dotsi x_n)\subseteq\mathbb{P}^{n+1}$. Following an SYZ type
approach, we produce an LG-model, whose Fukaya-Seidel category recovers line
bundles on $X_0$. As a byproduct of our approach, we answer a conjecture of
N.Sheridan about generating the small component of the Fukaya category of the
smooth index 1 Fano hypersurface in $\mathbb{P}^{n+1}$, without bounding
co-chains.
Chinese: 我们研究奇点超曲面$X_0=V(t^{n+1}-x_0\dotsi x_n)\subseteq\mathbb{P}^{n+1}$的同调镜像对称。遵循一种类似SYZ的方法，我们构造了一个LG模型，其Fukaya-Seidel范畴能够恢复$X_0$上的线束。作为我们方法的一个副产品，我们回答了N.Sheridan关于生成$\mathbb{P}^{n+1}$中光滑指数为1的Fano超曲面的Fukaya范畴的小分量的问题，而不对共链进行限制。
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English: Using first-principles full-potential density functional calculations, we
predict that mechanically tunable band-gap is realizable in ZnS monolayer in
graphene-like honeycomb structure by application of in-plane homogeneous
biaxial strain. A transition point from direct-to-indirect gap-phase is
predicted to exist for biaxial tensile strain lying in the interval (2.645%,
3.171%). In the two gap-phases, the band gap decreases with increasing strain
and varies linearly with strain.
Chinese: 利用第一性原理全势密度泛函计算，我们预测，通过施加平面内均匀的双轴应变，在石墨烯类蜂窝结构的ZnS单层中可以实现机械可调的带隙。预测存在一个从直接带隙到间接带隙相的过渡点，该过渡点位于双轴拉伸应变区间（2.645%，3.171%）内。在这两个带隙相中，随着应变的增加，带隙减小，并且与应变呈线性关系。
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English: Optical conductivity [$\sigma(\omega)$] of CeRhIn$_5$ and YbNi$_3$Ga$_9$ have
been measured at external pressures to 10 GPa and at low temperatures to 6 K.
Regarding CeRhIn$_5$, at ambient pressure the main feature in $\sigma(\omega)$
is a Drude peak due to free carriers. With increasing pressure, however, a
characteristic mid-infrared (mIR) peak rapidly develops in $\sigma(\omega)$,
and its peak energy and width increase with pressure. These features are
consistent with an increased conduction ($c$)-$f$ electron hybridization at
high pressure, and show that the pressure has tuned the electronic state of
CeRhIn$_5$ from very weakly to strongly hybridized ones. As for YbNi$_3$Ga$_9$,
in contrast, a marked mIR peak is observed already at ambient pressure,
indicating a strong $c$-$f$ hybridization. At high pressures, however, the mIR
peak shifts to lower energy and becomes diminished, and seems merged with the
Drude component at 10 GPa. Namely, CeRhIn$_5$ and YbNi$_3$Ga$_9$ exhibit some
opposite tendencies in the pressure evolutions of $\sigma(\omega)$ and
electronic structures. These results are discussed in terms of the pressure
evolutions of $c$-$f$ hybridized electronic states in Ce and Yb compounds, in
particular in terms of the electron-hole symmetry often considered between Ce
and Yb compounds.
Chinese: CeRhIn$_5$和YbNi$_3$Ga$_9$在外部压力至10 GPa和低温至6 K时的光学导电性[$\sigma(\omega)$]已被测量。对于CeRhIn$_5$，在常压下$\sigma(\omega)$的主要特征是由于自由载流子引起的Drude峰。然而，随着压力的增加，$\sigma(\omega)$中出现了典型的中红外(mIR)峰，并且其峰能量和宽度随压力增加而增大。这些特征与高压下$ c $-$ f $电子杂化增强是一致的，表明压力已经将CeRhIn$_5$的电子态从非常弱杂化的状态调至强杂化的状态。至于YbNi$_3$Ga$_9$，相反地，在常压下就观察到了明显的mIR峰，表明强烈的$ c $-$ f $杂化。然而，在高压下，mIR峰向较低能量移动并减弱，在10 GPa时似乎与Drude分量合并。换句话说，CeRhIn$_5$和YbNi$_3$Ga$_9$在$\sigma(\omega)$和电子结构的压力演化中表现出一些相反的趋势。这些结果从$ c $-$ f $杂化电子态在Ce和Yb化合物中压力演化角度进行了讨论，特别是从Ce和Yb化合物之间经常考虑的电子-空穴对称性角度进行了讨论。
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English: We study the deformation of spherical conical metrics with at least some of
the cone angles larger than $2\pi$. We show in this note via synthetic geometry
that for one family of such metrics, there is local rigidity in the choice of
cone positions if angles are fixed. This gives an evidence of the analytic
obstruction considered in recent works of Mazzeo and author.
Chinese: 我们研究了球锥度量在至少某些锥角大于$2\pi$时的形变。在这篇笔记中，我们通过综合几何表明，对于这样一类度量中的一个家族，如果角度固定，则锥位的选择具有局部刚性。这为Mazzeo和作者在近期工作中考虑的分析障碍提供了证据。
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English: The analysis of X-ray observations suggest an ultrastrong ($B\gtrsim 10^{14}
\,{\rm G}$) surface magnetic field at the polar cap of pulsars (Szary, 2013).
On the other hand, the temperature of the polar caps is about a few millions
Kelvin. Based on these two facts we use the Partially Screened Gap (PSG) model
to describe the Inner Acceleration Region (IAR). The PSG model assumes that the
temperature of the actual polar cap is equal to the so-called critical value,
i.e. the temperature at which the outflow of thermal ions from the surface
screens the gap completely. We have found that, depending on the conditions
above the polar cap, the generation of high energetic photons in IAR can be
caused either by Curvature Radiation (CR) or by Inverse Compton Scattering
(ICS). Completely different properties of both processes result in two
different scenarios of breaking the acceleration gap: the so-called PSG-off
mode for the gap dominated by CR and the PSG-on mode for the gap dominated by
ICS. The existence of two different mechanisms of gap breakdown naturally
explains the mode-changing phenomenon. Different characteristics of plasma
generated in the acceleration region for both modes also explain the pulse
nulling phenomenon.
Chinese: X射线观测分析表明，脉冲星极冠存在一个超强（$B\gtrsim 10^{14} \,{\rm G}$）的表面磁场（Szary, 2013）。另一方面，极冠的温度大约是几百万开尔文。基于这两个事实，我们使用部分屏蔽间隙（PSG）模型来描述内加速区（IAR）。PSG模型假设实际极冠的温度等于所谓的临界值，即热离子从表面完全屏蔽间隙的温度。我们发现，根据极冠上方的条件，IAR中高能光子的产生可以由曲率辐射（CR）或逆康普顿散射（ICS）引起。这两种过程完全不同的性质导致了两种不同的加速间隙断裂场景：对于以CR为主的间隙，称为PSG-off模式；对于以ICS为主的间隙，称为PSG-on模式。两种不同的间隙断裂机制的存在自然解释了模式转换现象。两种模式下在加速区产生的等离子体的不同特性也解释了脉冲消失现象。
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English: Conversational Question Generation (CQG) is a critical task for machines to
assist humans in fulfilling their information needs through conversations. The
task is generally cast into two different settings: answer-aware and
answer-unaware. While the former facilitates the models by exposing the
expected answer, the latter is more realistic and receiving growing attentions
recently. What-to-ask and how-to-ask are the two main challenges in the
answer-unaware setting. To address the first challenge, existing methods mainly
select sequential sentences in context as the rationales. We argue that the
conversation generated using such naive heuristics may not be natural enough as
in reality, the interlocutors often talk about the relevant contents that are
not necessarily sequential in context. Additionally, previous methods decide
the type of question to be generated (boolean/span-based) implicitly. Modeling
the question type explicitly is crucial as the answer, which hints the models
to generate a boolean or span-based question, is unavailable. To this end, we
present SG-CQG, a two-stage CQG framework. For the what-to-ask stage, a
sentence is selected as the rationale from a semantic graph that we construct,
and extract the answer span from it. For the how-to-ask stage, a classifier
determines the target answer type of the question via two explicit control
signals before generating and filtering. In addition, we propose Conv-Distinct,
a novel evaluation metric for CQG, to evaluate the diversity of the generated
conversation from a context. Compared with the existing answer-unaware CQG
models, the proposed SG-CQG achieves state-of-the-art performance.
Chinese: 会话式问题生成（CQG）是机器帮助人类通过对话满足其信息需求的关键任务。这项任务通常被设定为两种不同的场景：有答案意识和无答案意识。虽然前者通过揭示预期的答案来促进模型，但后者更符合现实，并最近受到了越来越多的关注。在无答案意识场景中，提出什么问题和如何提问是两大主要挑战。为了解决第一个挑战，现有方法主要选择上下文中的连续句子作为理由。我们认为，使用这种天真启发式方法生成的对话可能并不足够自然，因为在现实中，对话者通常会谈论上下文中相关的内容，而这些内容并不一定是连续的。此外，先前的方法隐式地决定了要生成的问答类型（布尔型/基于span的）。显式地建模问答类型至关重要，因为答案，它暗示模型生成布尔型或基于span的问答，是不可用的。为此，我们提出了SG-CQG，一个两阶段的CQG框架。在“提出什么问题”阶段，我们从我们构建的语义图中选择一个句子作为理由，并从中提取答案span。在“如何提问”阶段，一个分类器在生成和过滤之前通过两个显式控制信号确定问题的目标答案类型。此外，我们提出了Conv-Distinct，这是一种新颖的CQG评估指标，用于从上下文中评估生成对话的多样性。与现有的无答案意识CQG模型相比，所提出的SG-CQG实现了最先进的性能。
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English: Covariate balance is crucial in obtaining unbiased estimates of treatment
effects in observational studies. Methods based on inverse probability weights
have been widely used to estimate treatment effects with observational data.
Machine learning techniques have been proposed to estimate propensity scores.
These techniques however target accuracy instead of covariate balance. Methods
that target covariate balance have been successfully proposed and largely
applied to estimate treatment effects on continuous outcomes. However, in many
medical and epidemiological applications, the interest lies in estimating
treatment effects on time-to-event outcomes. With this type of data, one of the
most common estimands of interest is the marginal hazard ratio of the Cox
proportional hazard model. In this paper, we start by presenting robust
orthogonality weights (ROW), a set of weights obtained by solving a quadratic
constrained optimization problem that maximizes precision while constraining
covariate balance defined as the sample correlation between confounders and
treatment. By doing so, ROW optimally deal with both binary and continuous
treatments. We then evaluate the performance of the proposed weights in
estimating marginal hazard ratios of binary and continuous treatments with
time-to-event outcomes in a simulation study. We finally apply ROW on the
evaluation of the effect of hormone therapy on time to coronary heart disease
and on the effect of red meat consumption on time to colon cancer among 24,069
postmenopausal women enrolled in the Women's Health Initiative observational
study.
Chinese: 在观察性研究中，协变量平衡对于获得治疗效应的无偏估计至关重要。基于逆概率权重的方 法已被广泛用于估计基于观察数据的治疗效应。机器学习技术已被提出用于估计倾向得分。然而，这些技术以准确性为目标，而不是协变量平衡。针对协变量平衡的方法已被成功提出并广泛应用于估计连续结果的治 疗效应。然而，在许多医学和流行病学应用中，兴趣在于估计治疗对时间至事件结果的影响。对于这类数据，最常见的一个感兴趣的目标是Cox比例风险模型的边际风险比。在本文中，我们首先介绍了稳健正交权重（ROW），这是一组通过解决一个二次约束优化问题获得的权重，该问题在约束协变量平衡的同时最大化精度，协变量平衡定义为混杂因素与治疗之间的样本相关。通过这样做，ROW最优地处理了二进制和连续治疗。然后，我们在模拟研究中评估了所提出权重在估计具有时间至事件结果的二进制和连续治疗的边际风险比方面的性能。最后，我们将ROW应用于评估激素治疗对冠心病发生时间的影响，以及红肉消费对24,069名参加妇女健康倡议观察性研究的绝经后女性结肠癌发生时间的影响。
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English: In this paper we analyze, using scanning tunneling spectroscopy (STS), the
local density of electronic states (LDOS) in nearly optimally doped BSCCO in
zero field. We see both dispersive and non-dispersive spatial LDOS modulations
as a function of energy in our samples. Moreover, a spatial map of the
superconducting coherence peak heights shows the same structure as the low
energy LDOS. This suggests that these non-dispersive LDOS modulations originate
from an underlying charge-density modulation which interacts with
superconductivity.
Chinese: 在这篇论文中，我们使用扫描隧道光谱学（STS）分析了在零场下近最佳掺杂的BSCCO中的电子态密度（LDOS）。在我们的样品中，我们观察到随能量变化的分散和非分散空间LDOS调制。此外，超导相干峰高度的空间图显示出与低能LDOS相同的结构。这表明这些非分散LDOS调制起源于一个基本的电荷密度调制，它与超导性相互作用。
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English: Tables are everywhere, from scientific journals, papers, websites, and
newspapers all the way to items we buy at the supermarket. Detecting them is
thus of utmost importance to automatically understanding the content of a
document. The performance of table detection has substantially increased thanks
to the rapid development of deep learning networks. The goals of this survey
are to provide a profound comprehension of the major developments in the field
of Table Detection, offer insight into the different methodologies, and provide
a systematic taxonomy of the different approaches. Furthermore, we provide an
analysis of both classic and new applications in the field. Lastly, the
datasets and source code of the existing models are organized to provide the
reader with a compass on this vast literature. Finally, we go over the
architecture of utilizing various object detection and table structure
recognition methods to create an effective and efficient system, as well as a
set of development trends to keep up with state-of-the-art algorithms and
future research. We have also set up a public GitHub repository where we will
be updating the most recent publications, open data, and source code. The
GitHub repository is available at
https://github.com/abdoelsayed2016/table-detection-structure-recognition.
Chinese: 表格无处不在，从科学期刊、论文、网站到我们在超市购买的物品。因此，检测表格对于自动理解文档内容至关重要。得益于深度学习网络的快速发展，表格检测的性能得到了显著提高。本调查的目的是提供对表格检测领域主要发展的深刻理解，对不同的方法提供见解，并系统地分类不同的方法。此外，我们还对领域中的经典和新应用进行了分析。最后，我们对现有模型的数据库和源代码进行了组织，为读者提供了一本关于这一庞大文献的指南。最后，我们回顾了利用各种目标检测和表格结构识别方法构建一个有效且高效的系统的架构，以及一套保持与最先进算法和未来研究同步的开发趋势。我们还建立了一个公共GitHub仓库，我们将在此更新最新的出版物、开放数据和源代码。GitHub仓库的地址是https://github.com/abdoelsayed2016/table-detection-structure-recognition。
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English: The Transiting Exoplanet Survey Satellite (TESS) has discovered hundreds of
new worlds, with TESS planet candidates now outnumbering the total number of
confirmed planets from $\textit{Kepler}$. Owing to differences in survey
design, TESS continues to provide planets that are better suited for subsequent
follow-up studies, including mass measurement through radial velocity (RV)
observations, compared to Kepler targets. In this work, we present the
TESS-Keck Survey's (TKS) Mass Catalog: a uniform analysis of all TKS RV survey
data which has resulted in mass constraints for 126 planets and candidate
signals. This includes 58 mass measurements that have reached $\geq5\sigma$
precision. We confirm or validate 32 new planets from the TESS mission either
by significant mass measurement (15) or statistical validation (17), and we
find no evidence of likely false positives among our entire sample. This work
also serves as a data release for all previously unpublished TKS survey data,
including 9,204 RV measurements and associated activity indicators over our
three year survey. We took the opportunity to assess the performance of our
survey, and found that we achieved many of our goals including measuring the
mass of 38 small ($<4R_{\oplus}$) planets, nearly achieving the TESS mission's
basic science requirement. In addition, we evaluated the performance of the
Automated Planet Finder (APF) as survey support and observed meaningful
constraints on system parameters due to its more uniform phase coverage.
Finally, we compared our measured masses to those predicted by commonly used
mass-radius relations and investigated evidence of systematic bias.
Chinese: 凌日系外行星巡天卫星（TESS）已发现数百个新世界，目前TESS系外行星候选体的数量已超过开普勒任务确认行星的总数。由于巡天设计的差异，与开普勒目标相比，TESS持续提供更适合后续研究的行星，包括通过径向速度（RV）观测进行质量测量。在这项工作中，我们介绍了TESS-凯克巡天（TKS）质量目录：对所有TKS RV巡天数据的统一分析，已为126颗行星和候选信号提供了质量约束。这包括58个达到$\geq5\sigma$精度的质量测量。我们通过显著质量测量（15个）或统计验证（17个）的方式，确认或验证了TESS任务发现的32颗新行星，并且在我们整个样本中未发现可能的假阳性证据。这项工作还发布了所有此前未发表的TKS巡天数据，包括三年巡天期间采集的9,204个RV测量值及相关活动指标。我们抓住机会评估了巡天的性能，发现我们实现了许多目标，包括测量了38颗小型（$<4R_{\oplus}$）行星的质量，几乎达到了TESS任务的基本科学要求。此外，我们还评估了自动行星发现器（APF）作为巡天支持的性能，并由于其更均匀的相位覆盖，观察到系统参数的显著约束。最后，我们将测得质量与常用质量-半径关系预测值进行了比较，并调查了系统性偏差的证据。
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English: Today's most popular techniques for accurately calculating the dynamics of
the reduced density operator in an open quantum system, either require, or gain
great computational benefits, from representing the bath response function a(t)
in the form a(t)={\Sigma}_k^K p_k e^{O_k t} . For some of these techniques, the
number of terms in the series K plays the lead role in the computational cost
of the calculation, and is therefore often a limiting factor in simulating open
quantum system dynamics. We present an open source MATLAB program called
BATHFIT 1, whose input is any spectral distribution functions J(w) or bath
response function, and whose output attempts to be the set of parameters
{p_k,w_k}_k=1^K such that for a given value of K, the series {\Sigma}_k^k p_k
e^{O_k t} is as close as possible to a(t). This should allow the user to
represent a(t) as accurately as possible with as few parameters as possible.
The program executes non-linear least squares fitting, and for a very wide
variety of spectral distribution functions, competent starting parameters are
used for these fits. For most forms of J(w), these starting parameters, and the
exact a(t) corresponding to the given J(w), are calculated using the recent
Pade decomposition technique - therefore this program can also be used to
merely implement the Pade decomposition for these spectral distribution
functions; and it can also be used just to efficiently and accurately calculate
a(t) for any given J(w) . The program also gives the J(w) corresponding to a
given a(t), which may allow one to assess the quality (in the w-domain) of a
representation of a(t) being used. Finally, the program can calculate the
discretized influence functional coefficients for any J(w), and this is
computed very efficiently for most forms of J(w) by implementing the recent
technique published in [Quantum Physics Letters (2012) 1 (1) pg. 35].
Chinese: 今日最流行的用于准确计算开放量子系统中简化密度算符动力学的方法，要么需要，要么从将浴响应函数 a(t) 表示为 a(t)={\Sigma}_k^K p_k e^{O_k t} 的形式中获得巨大的计算效益。对于这些方法中的一些，级数 K 中的项数在计算的代价中扮演着主导角色，因此常常是模拟开放量子系统动力学的一个限制因素。我们提出一个开源的 MATLAB 程序，称为 BATHFIT 1，其输入是任何光谱分布函数 J(w) 或浴响应函数，其输出试图是参数集 {p_k,w_k}_k=1^K，使得对于给定的 K 值，级数 {\Sigma}_k^k p_k e^{O_k t} 尽可能接近 a(t)。这应该允许用户尽可能准确地用尽可能少的参数来表示 a(t)。
程序执行非线性最小二乘拟合，并且对于非常广泛的光谱分布函数，使用了这些拟合的合适起始参数。对于 J(w) 的大多数形式，这些起始参数以及与给定 J(w) 对应的精确 a(t)，都是使用最近提出的 Pade 分解技术计算的——因此这个程序也可以用来仅仅实现这些光谱分布函数的 Pade 分解；它也可以用来高效且准确地计算任何给定 J(w) 的 a(t)。
程序还给出了与给定 a(t) 对应的 J(w)，这可能允许评估正在使用的 a(t) 表示的质量（在 w 领域）。最后，程序可以计算任何 J(w) 的离散化影响函数系数，对于 J(w) 的大多数形式，通过实现最近在 [Quantum Physics Letters (2012) 1 (1) pg. 35] 发表的技术的计算效率非常高。
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English: Originally developed as a theory of consciousness, integrated information
theory provides a mathematical framework to quantify the causal irreducibility
of systems and subsets of units in the system. Specifically, mechanism
integrated information quantifies how much of the causal powers of a subset of
units in a state, also referred to as a mechanism, cannot be accounted for by
its parts. If the causal powers of the mechanism can be fully explained by its
parts, it is reducible and its integrated information is zero. Here, we study
the upper bound of this measure and how it is achieved. We study mechanisms in
isolation, groups of mechanisms, and groups of causal relations among
mechanisms. We put forward new theoretical results that show mechanisms that
share parts with each other cannot all achieve their maximum. We also introduce
techniques to design systems that can maximize the integrated information of a
subset of their mechanisms or relations. Our results can potentially be used to
exploit the symmetries and constraints to reduce the computations significantly
and to compare different connectivity profiles in terms of their maximal
achievable integrated information.
Chinese: 最初作为意识理论发展起来的集成信息理论，提供了一个数学框架来量化系统及其子集的因果不可约性。具体来说，机制集成信息量化了在某个状态下的单位子集（也称为机制）的因果力量中，有多少不能由其部分来解释。如果机制的因果力量可以完全由其部分来解释，那么它是可约的，其集成信息为零。在这里，我们研究这一度量标准的上限及其实现方式。我们研究了独立机制、机制组以及机制之间的因果关系组。我们提出了新的理论结果，表明相互共享部分的机制不能都达到最大值。我们还介绍了设计系统的技术，这些系统能够最大化其机制或关系子集的集成信息。我们的结果有可能被用来利用对称性和约束条件来显著减少计算量，并从最大可实现的集成信息的角度比较不同的连接配置文件。
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English: We study the relationship between $n$-cluster tilting modules over $n$
representation finite algebras and the Euler forms. We show that the dimension
vectors of cluster-indecomposable modules give the roots of the Euler form.
Moreover, we show that cluster-indecomposable modules are uniquely determined
by their dimension vectors. This is a generalization of Gabriel's theorem by
cluster tilting theory. We call the above roots cluster-roots and investigate
their properties. Furthermore, we provide the description of quivers with
relations of $n$-APR tilts. Using this, we provide a generalization of BGP
reflection functors.
Chinese: 我们研究 $n$-表示有限代数上的 $n$-簇倾斜模与欧拉形式之间的关系。我们证明，簇不可分模的维数向量给出欧拉形式的根。此外，我们证明簇不可分模由其维数向量唯一确定。这是通过簇倾斜理论推广了加布里埃尔定理。我们称上述根为簇根，并研究它们的性质。此外，我们提供了具有 $n$-APR 倾斜关系的图的描述。利用这一点，我们提供了 BGP 反射函子的推广。
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English: We show that the new technique of terahertz 2D coherent spectroscopy is
capable of giving qualitatively new information about fractionalized spin
systems. For the prototypical example of the transverse field Ising chain, we
demonstrate theoretically that, despite the broad continuum of excitations in
linear response, the 2D spectrum contains sharp features that are a coherent
signature of a `spinon echo', which gives previously inaccessible information
such as the lifetime of the two-spinon excited state. The effects of disorder
and finite lifetime, which are practically indistinguishable in the linear
optical or neutron response, manifest in dramatically different fashion in the
2D spectra. Our results may be directly applicable to model quasi-1D transverse
field Ising chain systems such as CoNb$_2$O$_6$, but the concept can be applied
to fractionalized spin systems in general.
Chinese: 我们证明了太赫兹二维相干光谱的新技术能够为分数化自旋系统提供定性的新信息。以横向场伊辛链为典型例子，我们理论上展示了，尽管在线性响应中激发具有宽的连续谱，二维光谱中却包含着尖锐的特征，这些特征是“自旋子回波”的相干信号，它提供了先前无法获取的信息，例如双自旋子激发态的寿命。无序效应和有限寿命的影响，在线性光学或中子响应中实际上是无法区分的，但在二维光谱中却以截然不同的方式表现出来。我们的结果可以直接应用于模型准一维横向场伊辛链系统，如CoNb$_2$O$_6$，但该概念可应用于一般的分数化自旋系统。
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English: Relying upon tools from the theory of integrable systems, we discuss the
linear instability of the Kuznetsov-Ma breathers and the Akhmediev breathers of
the focusing nonlinear Schr{\"o}dinger equation. We use the Darboux
transformation to construct simultaneously the breathers and the exact
solutions of the Lax system associated with the breathers. We obtain a full
description of the Lax spectra for the two breathers, including multiplicities
of eigenvalues. Solutions of the linearized NLS equations are then obtained
from the eigenfunctions and generalized eigenfunctions of the Lax system. While
we do not attempt to prove completeness of eigenfunctions, we aim to determine
the entire set of solutions of the linearized NLS equations generated by the
Lax system in appropriate function spaces.
Chinese: 利用可积系统理论中的工具，我们讨论了库兹涅佐夫-马呼吸子以及聚焦非线性薛定谔方程中的阿赫梅德耶夫呼吸子的线性不稳定性。我们使用达布变换同时构造呼吸子和与呼吸子相关的Lax系统的精确解。我们获得了这两个呼吸子的Lax谱的完整描述，包括特征值的重数。然后，我们从Lax系统的本征函数和广义本征函数中得到了线性化NLS方程的解。虽然我们没有试图证明本征函数的完备性，但我们旨在确定由Lax系统在适当的函数空间中产生的线性化NLS方程的全部解集。
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English: To date no satisfying model exists to explain the mean velocity profile
within the whole turbulent layer of canonical wall bounded flows. We propose a
modification of the velocity profile expression that ensues from a recently
proposed stochastic representation of fluid flows dynamics. This modeling,
called modeling under location uncertainty introduces in a rigorous way a
subgrid term generalizing the eddy-viscosity assumption and an eddy-induced
advection term resulting from turbulence inhomogeneity. This latter term gives
rise to a theoretically well-grounded model for the transitional zone between
the viscous sublayer and the turbulent sublayer. An expression of the
small-scale velocity component is also provided in the viscous zone. Numerical
assessment of the results are provided for turbulent boundary layer flows, for
pipe flows and channel flows at various Reynolds numbers.
Chinese: 到目前为止，还没有令人满意的模型能够解释典型壁面约束流动整个湍流层内的平均速度分布。我们提出了一种修改速度分布表达式的模型，该模型源自最近提出的流体动力学随机表示。这种建模，称为位置不确定性下的建模，以严格的方式引入了一个亚网格项，该项一般化了湍流粘性假设，并引入了一个湍流不均匀性导致的涡动诱导对流项。后者产生了理论基础坚实的模型，用于粘性亚层与湍流亚层之间的过渡区域。在粘性区域还提供了小尺度速度分量的表达式。对于湍流边界层流动、管流和通道流在各种雷诺数下的数值评估结果也提供了证明。
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English: Recurrent Neural Networks (RNNs) frequently exhibit complicated dynamics, and
their sensitivity to the initialization process often renders them notoriously
hard to train. Recent works have shed light on such phenomena analyzing when
exploding or vanishing gradients may occur, either of which is detrimental for
training dynamics. In this paper, we point to a formal connection between RNNs
and chaotic dynamical systems and prove a qualitatively stronger phenomenon
about RNNs than what exploding gradients seem to suggest. Our main result
proves that under standard initialization (e.g., He, Xavier etc.), RNNs will
exhibit \textit{Li-Yorke chaos} with \textit{constant} probability
\textit{independent} of the network's width. This explains the experimentally
observed phenomenon of \textit{scrambling}, under which trajectories of nearby
points may appear to be arbitrarily close during some timesteps, yet will be
far away in future timesteps. In stark contrast to their feedforward
counterparts, we show that chaotic behavior in RNNs is preserved under small
perturbations and that their expressive power remains exponential in the number
of feedback iterations. Our technical arguments rely on viewing RNNs as random
walks under non-linear activations, and studying the existence of certain types
of higher-order fixed points called \textit{periodic points} that lead to phase
transitions from order to chaos.
Chinese: 循环神经网络（RNNs）经常表现出复杂的动力学，并且它们对初始化过程的高度敏感性常常使它们难以训练。近期的研究通过分析爆炸梯度或消失梯度可能发生的情况，揭示了这些现象，而两者都对训练动力学有害。在本文中，我们指出了RNNs与混沌动力系统之间的正式联系，并证明了一个比爆炸梯度所暗示的更强的RNN现象。我们的主要结果证明，在标准初始化（例如He、Xavier等）下，RNNs将以\textit{常数}概率表现出\textit{Li-Yorke混沌}\textit{独立于}网络的宽度。这解释了实验中观察到的\textit{打乱}\现象，在该现象下，邻近点的轨迹在某些时间步长内可能看起来任意接近，但在未来的时间步长中将相距甚远。与它们的顺馈对应物形成鲜明对比，我们证明了RNNs中的混沌行为在小扰动下得以保留，并且它们的表达能力在反馈迭代次数上仍然是指数级的。我们的技术论证依赖于将RNNs视为非线性激活下的随机游走，并研究一类称为\textit{周期点}的高阶固定点的存在，这些固定点会导致从有序到混沌的相变。
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English: We report the results of the first study of the multi-stream environment of
dark matter haloes in cosmological N-body simulations in the LCDM cosmology.
The full dynamical state of dark matter can be described as a three-dimensional
sub-manifold in six dimensional phase space - the dark matter sheet. In our
study we use a Lagrangian sub-manifold x = x(q,t) (where x and q are co-moving
Eulerian and Lagrangian coordinates respectively), which is dynamically
equivalent to the dark matter sheet but is more convenient for numerical
analysis. Our major results can be summarized as follows. At the resolution of
the simulation i.e. without additional smoothing, the cosmic web represents a
hierarchical structure: each halo is embedded in the filamentary framework of
the web predominantly at the filament crossings, and each filament is embedded
in the wall like fabric of the web at the wall crossings. Locally, each halo or
sub-halo is a peak in the number of streams field. The number of streams in the
neighbouring filaments is higher than in the neighbouring walls. The walls are
regions where number of streams is equal to three or a few. Voids are uniquely
defined by the local condition requiring to be a single-stream flow region. The
shells of streams around haloes are quite thin and the closest void region is
typically within one and a half FOF radius from the center of the halo.
Chinese: 我们报告了在LCDM宇宙学中，基于宇宙学N体模拟对暗物质晕多流环境的首次研究。暗物质的整体动力学状态可以描述为六维相空间中的一个三维子流形——暗物质片。在我们的研究中，我们使用了一个拉格朗日子流形x = x(q,t)（其中x和q分别是共动欧拉坐标和拉格朗日坐标），它与暗物质片在动力学上等效，但更适合数值分析。我们的主要结果可以总结如下。在模拟的分辨率下，即不进行额外平滑时，宇宙网代表了一种层级结构：每个晕主要嵌入在宇宙网丝状框架的交叉处，而每个丝状结构则嵌入在宇宙网壁状结构（墙状结构）的交叉处。在局部范围内，每个晕或子晕都是流场中的峰值。邻近丝状结构中的流数量高于邻近壁状结构中的流数量。壁状结构是流数量等于三或几个的区域。空隙（voids）由局部条件唯一定义，即必须是单一流区域。晕周围的流壳非常薄，最近的空隙区域通常位于晕中心距离一个半FOF半径（friends-of-friends radius）范围内。
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English: Let $(\xi_j)_{j\ge1} $, be a non-stationary Markov chain with phase space $X$
and let $\mathfrak{g}_j:\,X\mapsto\mathrm{SL}(m,\mathbb{R})$ be a sequence of
functions on $X$ with values in the unimodular group. Set
$g_j=\mathfrak{g}_j(\xi_j)$ and denote by $S_n=g_n\ldots g_1$, the product of
the matrices $g_j$. We provide sufficient conditions for exponential growth of
the norm $\|S_n\|$ when the Markov chain is not supposed to be stationary. This
generalizes the classical theorem of Furstenberg on the exponential growth of
products of independent identically distributed matrices as well as its
extension by Virtser to products of stationary Markov-dependent matrices.
Chinese: 设 $(\xi_j)_{j\ge1} $ 为一个非平稳马尔可夫链，其相空间为 $X$，并且设 $\mathfrak{g}_j:\,X\mapsto\mathrm{SL}(m,\mathbb{R})$ 是定义在 $X$ 上的一个函数序列，其值在单模群中。令 $g_j=\mathfrak{g}_j(\xi_j)$，并记 $S_n=g_n\ldots g_1$ 为矩阵 $g_j$ 的乘积。当马尔可夫链不假定是平稳的时，我们提供了 $\|S_n\|$ 范数指数增长的充分条件。这推广了Furstenberg关于独立同分布矩阵乘积指数增长的经典定理，以及Virtser对平稳马尔可夫相关矩阵乘积的推广。
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English: The aim of this paper is to develop a general framework for training neural
networks (NNs) in a distributed environment, where training data is partitioned
over a set of agents that communicate with each other through a sparse,
possibly time-varying, connectivity pattern. In such distributed scenario, the
training problem can be formulated as the (regularized) optimization of a
non-convex social cost function, given by the sum of local (non-convex) costs,
where each agent contributes with a single error term defined with respect to
its local dataset. To devise a flexible and efficient solution, we customize a
recently proposed framework for non-convex optimization over networks, which
hinges on a (primal) convexification-decomposition technique to handle
non-convexity, and a dynamic consensus procedure to diffuse information among
the agents. Several typical choices for the training criterion (e.g., squared
loss, cross entropy, etc.) and regularization (e.g., $\ell_2$ norm, sparsity
inducing penalties, etc.) are included in the framework and explored along the
paper. Convergence to a stationary solution of the social non-convex problem is
guaranteed under mild assumptions. Additionally, we show a principled way
allowing each agent to exploit a possible multi-core architecture (e.g., a
local cloud) in order to parallelize its local optimization step, resulting in
strategies that are both distributed (across the agents) and parallel (inside
each agent) in nature. A comprehensive set of experimental results validate the
proposed approach.
Chinese: 本文的目标是开发一个通用的框架，用于在分布式环境中训练神经网络（NNs），其中训练数据被分配到一组通过稀疏、可能随时间变化的连接模式相互通信的代理上。在这样的分布式场景中，训练问题可以表述为（正则化的）非凸社会成本函数的优化，该函数由局部（非凸）成本的总和给出，其中每个代理通过与其局部数据集相关的单个误差项做出贡献。为了设计一个灵活且高效的解决方案，我们定制了一个最近提出的网络非凸优化的框架，该框架依赖于一个（原函数）凸化-分解技术来处理非凸性，以及一个动态共识过程来在代理之间传播信息。框架中包含了几个典型的训练标准（例如，平方损失、交叉熵等）和正则化（例如，$\ell_2$范数、稀疏性诱导惩罚等）的选择，并在整篇文章中进行了探讨。在温和的假设下，保证了社会非凸问题收敛到稳态解。此外，我们展示了一种原则性的方法，允许每个代理利用可能的多核架构（例如，本地云）来并行化其局部优化步骤，从而产生在本质上既分布式（跨代理）又并行（在每个代理内部）的策略。一系列全面的实验结果验证了所提出的方法。
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English: We describe the easy to customize and extend open source Java program Central
force workbench that can be used in the classroom to simulate the motion of a
particle (or a two-body system) under central forces. It may be useful to
illustrate problems in which the analytical solution is not available as well
as to help students to grasp a more intuitive understanding of the main
features of this kind of problem and to realize the exceptional nature of the
particular case of Newtonian (and harmonic) forces. We also include some
suggestions on how to use the program as a pedagogical tool.
Chinese: 我们描述了一个易于定制和扩展的开源Java程序Central force workbench，该程序可以在课堂上用于模拟在中心力作用下粒子的运动（或双体系统）。在无法获得解析解的问题中，它可能很有用，同时也有助于学生更直观地理解这类问题的主要特征，并认识到牛顿力（和调和力）特殊情况的特殊性质。我们还提供了一些关于如何将程序用作教学工具的建议。
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English: We propose a theory which deals with the structure and interactions of volume
elements in liquid helium II. The approach consists of two nested models linked
via parametric space. The short-wavelength part describes the interior
structure of the fluid element using a non-perturbative approach based on the
logarithmic wave equation; it suggests the Gaussian-like behaviour of the
element's interior density and interparticle interaction potential. The
long-wavelength part is the quantum many-body theory of such elements which
deals with their dynamics and interactions. Our approach leads to a unified
description of the phonon, maxon and roton excitations, and has noteworthy
agreement with experiment: with one essential parameter to fit we reproduce at
high accuracy not only the roton minimum but also the neighboring local maximum
as well as the sound velocity and structure factor.
Chinese: 我们提出了一种理论，该理论处理液氦II中体积元素的结构和相互作用。该方法由两个嵌套模型组成，通过参数空间相互连接。短波长部分使用基于对数波动方程的非微扰方法描述流体元素的内部结构；它暗示了元素内部密度和粒子间相互作用势的类似于高斯的行为。长波长部分是此类元素的量子多体理论，处理它们的动力学和相互作用。我们的方法导致了对声子、马宗和罗顿激发的统一描述，并且与实验有显著的吻合：仅用一个基本参数进行拟合，我们不仅以高精度再现了罗顿最小值，还再现了邻近的局部最大值以及声速和结构因子。
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English: In finite-temperature field theory, the cyclic Wilson loop is defined as a
rectangular Wilson loop spanning the whole compactified time direction. In a
generic non-abelian gauge theory, we calculate the perturbative expansion of
the cyclic Wilson loop up to order g^4. At this order and after charge
renormalization, the cyclic Wilson loop is known to be ultraviolet divergent.
We show that the divergence is not associated with cusps in the contour but is
instead due to the contour intersecting itself because of the periodic boundary
conditions. One consequence of this is that the cyclic Wilson loop mixes under
renormalization with the correlator of two Polyakov loops. The resulting
renormalization equation is tested up to order g^6 and used to resum the
leading logarithms associated with the intersection divergence. Implications
for lattice studies of this operator, which may be relevant for the
phenomenology of quarkonium at finite temperature, are discussed.
Chinese: 在有限温度场论中，循环威尔逊环被定义为跨越整个紧化时间方向的矩形威尔逊环。在一般的非阿贝尔规范理论中，我们计算了循环威尔逊环的微扰展开，直到g^4阶。在这个阶数和电荷重整化之后，循环威尔逊环已知是紫外发散的。我们表明，这种发散不是与轮廓中的尖点相关联，而是由于周期性边界条件导致轮廓自身相交。这一结果的一个后果是，循环威尔逊环在重整化过程中与两个波利亚科夫环的关联函数混合。得到的重整化方程被检验到g^6阶，并用于重整与交点发散相关的首项对数。讨论了此算符在晶格研究中的含义，这可能对有限温度下夸克onia的物理现象学相关。
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English: Zero-shot Learners are models capable of predicting unseen classes. In this
work, we propose a Zero-shot Learning approach for text categorization. Our
method involves training model on a large corpus of sentences to learn the
relationship between a sentence and embedding of sentence's tags. Learning such
relationship makes the model generalize to unseen sentences, tags, and even new
datasets provided they can be put into same embedding space. The model learns
to predict whether a given sentence is related to a tag or not; unlike other
classifiers that learn to classify the sentence as one of the possible classes.
We propose three different neural networks for the task and report their
accuracy on the test set of the dataset used for training them as well as two
other standard datasets for which no retraining was done. We show that our
models generalize well across new unseen classes in both cases. Although the
models do not achieve the accuracy level of the state of the art supervised
models, yet it evidently is a step forward towards general intelligence in
natural language processing.
Chinese: 零样本学习器是能够预测未见类别的模型。在这项工作中，我们提出了一种用于文本分类的零样本学习方法。我们的方法涉及在一个大型句子语料库上训练模型，以学习句子与其标签嵌入之间的关系。学习这种关系使得模型能够泛化到未见句子、标签，甚至新数据集，前提是它们可以被放入相同的嵌入空间。模型学习预测给定句子是否与某个标签相关；与学习将句子分类为可能类别之一的其他分类器不同。我们为该任务提出了三种不同的神经网络，并报告了它们在用于训练它们的训练数据集测试集上的准确率，以及两个没有进行重新训练的标准数据集。我们表明，在两种情况下，我们的模型在新的未见类别上都具有良好的泛化能力。尽管这些模型没有达到最先进的有监督模型的准确率水平，但显然是自然语言处理中向通用智能迈进的一步。
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English: When there is a family of complex structures on the phase space, parametrized
by a set $S$, the prequantum Hilbert spaces produced by geometric quantization,
using the half-form correction, also depends on these parameters. This way we
obtain a field of Hilbert spaces $p:H^{pr Q}\rightarrow S$. We show that this
field can have natural inequivalent smooth Hilbert bundle structures.
Chinese: 当相空间上存在一组由集合 $S$ 参数化的复杂结构时，使用半形式校正进行几何量子化产生的预量子希尔伯特空间，也依赖于这些参数。这样我们就得到了一个希尔伯特空间场 $p:H^{pr Q}\rightarrow S$。我们证明了这个场可以具有自然不等价的平滑希尔伯特丛结构。
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English: The high frequency peaked BL Lac PKS 2155-304 with a redshift z=0.116 was
discovered 1997 in the VHE range by the University of Durham Mark 6 gamma-ray
telescope in Australia with a flux corresponding to approx. 0.2 times the Crab
Nebula flux. It was later observed and detected with high significance by the
Southern observatories CANGAROO and H.E.S.S. establishing this source as the
best studied Southern TeV blazar. Detection from the Northern hemisphere was
very difficult due to challenging observation conditions under large zenith
angles. In July 2006, the H.E.S.S. collaboration reported an extraordinary
outburst of VHE gamma-emission. During the outburst, the VHE gamma-ray emission
was found to be variable on the time scales of minutes and at a mean flux of
approx. 7 times the flux observed from the Crab Nebula. The MAGIC collaboration
operates a 17m imaging air Cherenkov Telescope at La Palma (Northern
Hemisphere). Follow up observations of the extraordinary outburst have been
triggered in a Target of Opportunity program by an alert from the H.E.S.S.
collaboration. The measured spectrum and light curve are presented.
Chinese: 红移z=0.116的高频峰值BL Lac天体PKS 2155-304于1997年被澳大利亚的杜伦大学Mark 6伽马射线望远镜在VHE波段发现，其流量相当于蟹状星云流量的约0.2倍。后来，南半球的天文台CANGAROO和H.E.S.S.对其进行了观测并具有高度显著性，确立了该天体为研究最充分的南半球TeV类星体。由于在大的天顶角下观测条件具有挑战性，北半球的探测非常困难。2006年7月，H.E.S.S.合作组报告了VHE伽马射线辐射的异常爆发。在爆发期间，VHE伽马射线辐射被发现具有分钟时间尺度的变化，平均流量约为蟹状星云观测流量的7倍。MAGIC合作组在拉帕尔马（北半球）运营一台17米成像空气切伦科夫望远镜。由H.E.S.S.合作组的警报触发了在目标机会计划中的异常爆发的后续观测。测量的光谱和光变曲线被呈现。
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English: We use scanning tunneling microscopy to study the domain structure of the
nearly-commensurate charge density wave (NC-CDW) state of 1T-TaS$_2$. In our
sub-angstrom characterization of the state, we find a continual evolution of
the CDW lattice from domain wall to domain center, instead of a fixed CDW
arrangement within a domain. Further, we uncover an intradomain chirality
characterizing the NC-CDW state. Unlike the orbital-driven chirality previously
observed in related transition metal dichalcogenides, the chiral nature of the
NC-CDW state in 1T-TaS$_2$ appears driven by a strong coupling of the NC-CDW
state to the lattice.
Chinese: 我们使用扫描隧道显微镜研究1T-TaS2中几乎相干的电荷密度波（NC-CDW）态的域结构。在我们的亚埃格斯特朗姆表征中，我们发现CDW晶格从域壁到域中心持续演化，而不是域内固定的CDW排列。此外，我们揭示了NC-CDW态的域内手性。与先前在相关过渡金属二硫化物中观察到的轨道驱动手性不同，1T-TaS2中NC-CDW态的手性特征似乎是由NC-CDW态与晶格的强耦合驱动的。
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English: Ion-mobility spectrometry (IMS) is an analytical technique used to separate
and identify ionized gas molecules based on their mobility in a carrier buffer
gas. Such methods come in a large variety of versions that currently allow ion
identification at and above the millimeter scale. Here, we present a design for
a cross-flow-IMS method able to generate and detect ions at the sub-millimeter
scale. We propose a novel ion focusing strategy and tested it in a prototype
device using Nitrogen as a sample gas, and also with simulations using four
different sample gases. By introducing an original lobular ion generation
localized to a few ten of microns and substantially simplifying the design, our
device is able to keep constant laminar flow conditions for high flow rates. In
this way, it avoids the turbulences in the gas flow, which would occur in other
ion-focusing cross-flow methods limiting their performance at the
sub-millimeter scale. Scalability of the proposed design can contribute to
improve resolving power and resolution of currently available cross-flow
methods.
Chinese: 离子迁移谱法（IMS）是一种分析技术，用于根据离子在载气缓冲气中的迁移能力分离和鉴定离子化气体分子。这类方法种类繁多，目前能够实现毫米级以上的离子鉴定。在这里，我们提出了一种设计用于跨流IMS方法，该方法能够生成和检测亚毫米级的离子。我们提出了一种新的离子聚焦策略，并在使用氮气作为样品气体的原型设备中进行了测试，同时也使用四种不同的样品气体进行了模拟。通过引入一种原型的球状离子生成，局限于几微米，并且大大简化了设计，我们的设备能够在高流速下保持恒定的层流流动条件。这样，它避免了气体流动中的湍流，这在其他的离子聚焦跨流方法中会发生，限制了它们在亚毫米级上的性能。所提出的设计可扩展性有助于提高当前可用的跨流方法的分辨能力和分辨率。
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English: In this paper, we study the existence and stability of travelling wave
solutions of a kinetic reaction-transport equation. The model describes
particles moving according to a velocity-jump process, and proliferating thanks
to a reaction term of monostable type. The boundedness of the velocity set
appears to be a necessary and sufficient condition for the existence of
positive travelling waves. The minimal speed of propagation of waves is
obtained from an explicit dispersion relation. We construct the waves using a
technique of sub- and supersolutions and prove their \eb{weak} stability in a
weighted $L^2$ space. In case of an unbounded velocity set, we prove a
superlinear spreading. It appears that the rate of spreading depends on the
decay at infinity of the velocity distribution. In the case of a Gaussian
distribution, we prove that the front spreads as $t^{3/2}$.
Chinese: 在这篇论文中，我们研究了动量反应-传输方程中行波解的存在性和稳定性。该模型描述了根据速度跳跃过程移动的粒子，并通过单稳态类型的反应项进行增殖。速度集的有界性似乎对于正行波的存在是必要且充分的条件。波传播的最小速度从显式的色散关系中得出。我们使用亚解和超解技术构建波，并在加权 $L^2$ 空间中证明了它们的弱稳定性。在速度集无界的情况下，我们证明了超线性扩散。似乎扩散速率取决于速度分布的无限衰减率。在高斯分布的情况下，我们证明了前沿以 $t^{3/2}$ 的速率扩散。
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English: New algorithm of the finite lattice method is presented to generate the
high-temperature expansion series of the Ising model. It enables us to obtain
much longer series in three dimensions when compared not only to the previous
algorithm of the finite lattice method but also to the standard graphical
method. It is applied to extend the high-temperature series of the simple cubic
Ising model from beta^{26} to beta^{46} for the free energy and from beta^{25}
to beta^{32} for the magnetic susceptibility.
Chinese: 新提出的有限格点法的新算法用于生成伊辛模型的低温展开级数。与之前的有限格点法算法相比，甚至与标准图形方法相比，它使我们能够在三维空间中获得更长的级数。它被应用于将简单立方伊辛模型的自由能高温级数从beta^{26}扩展到beta^{46}，并将磁化率高温级数从beta^{25}扩展到beta^{32}。
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English: The lepton-flavour-violating decay K_L --> e \mu is studied in detail within
the context of SU(2)_R x SU(2)_L x U(1)_(B-L) models, which include heavy
Majorana neutrinos. Particular attention is paid to the gauge independence of
this decay process to one loop. In analogy with earlier studies on the
K^0\bar{K}^0 mixing, it is explicitly shown how restoration of gauge invariance
occurs in the decay amplitude containing the box diagrams, when the relevant
Higgs-dependent self-energy and vertex graphs are taken into account in the
on-shell skeleton renormalization scheme. Based on the analytic expressions so
derived, we find that the branching ratio B(K_L --> e \mu) can be considerably
enhanced due to the presence of left- and right-handed currents in the loop,
and can reach values close to or even larger than the present experimental
limit 3.3 x 10^{-11} in the manifest left-right symmetric model. Constraints on
the parameter space of typical left-right models are derived from the possible
decay K_L --> e \mu and a global analysis of other low-energy data.
Chinese: 在SU(2)_R x SU(2)_L x U(1)_(B-L)模型中，详细研究了违反轻子味的衰变K_L --> e \mu，这些模型包括重Majorana中微子。特别关注了这个衰变过程在一环中的规范不变性。与之前对K^0\bar{K}^0混合的研究类似，明确展示了在考虑相关的Higgs相关的自能和顶点图时，在壳骨架重整化方案中，如何通过箱图恢复规范不变性。基于这样推导出的解析表达式，我们发现由于回路中存在左旋和右旋电流，分支比B(K_L --> e \mu)可以显著增强，并且可以接近甚至超过在明显左右对称模型中的当前实验极限3.3 x 10^{-11}。从可能的衰变K_L --> e \mu和其他低能数据的全局分析中，推导出了典型左右模型参数空间的限制。
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English: We study the temperature-filling phase diagram of the single-band Holstein
model in two dimensions using the self-consistent Migdal approximation, where
both the electron and phonon self-energies are treated on an equal footing. By
employing an efficient numerical algorithm utilizing fast Fourier transforms to
evaluate momentum and Matsubara frequency summations, we determine the
charge-density-wave (CDW) and superconducting transition temperatures in the
thermodynamic limit using lattice sizes that are sufficient to eliminate
significant finite size effects present at lower temperatures. We obtain the
temperature-filling phase diagrams for a range of coupling strengths and phonon
frequencies for the model defined on a square lattice with and without
next-nearest neighbor hopping. We find the appearance of a superconducting dome
with a critical temperature that decreases before reaching the
$\mathbf{q}_{\text{max}} = (\pi,\pi)$ CDW phase boundary. For very low phonon
frequencies, we also find an incommensurate CDW phase with the ordering vector
$\mathbf{q}_{\text{max}} \approx (\pi,\pi)$ appearing between the commensurate
CDW and superconducting phases. Our numerical implementation can be easily
extended to treat momentum-dependent electron-phonon coupling, as well as
dispersive phonon branches, and has been made available to the public.
Chinese: 我们使用自洽米格达尔近似法研究了二维单带霍尔特模型温度-填充相图，其中电子和声子的自能被同等对待。通过采用一种高效的数值算法，利用快速傅里叶变换来评估动量和 Matsubara 频率的求和，我们确定了在热力学极限下的电荷密度波（CDW）和超导转变温度，所使用的晶格大小足以消除在较低温度下存在的显著有限尺寸效应。我们得到了在方形晶格上定义的模型，考虑和未考虑最近邻跳跃的耦合强度和声子频率范围内的温度-填充相图。我们发现了一个超导穹顶的出现，其临界温度在达到 $\mathbf{q}_{\text{max}} = (\pi,\pi)$ CDW 相边界之前降低。对于非常低的声子频率，我们还发现了一个不匹配的 CDW 相，其有序向量 $\mathbf{q}_{\text{max}} \approx (\pi,\pi)$ 出现在匹配的 CDW 和超导相之间。我们的数值实现可以很容易地扩展以处理动量依赖的电子-声子耦合，以及色散的声子分支，并且已经向公众开放。
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