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English: We use food webs generated by a model to investigate the effects of deleting
species on other species in the web and on the web as a whole. The model
incorporates a realistic population dynamics, adaptive foragers and other
features which allow for the construction of model webs which resemble
empirical food webs. A large number of simulations were carried out to produce
a substantial number of model webs on which deletion experiments could be
performed. We deleted each species in four hundred distinct model webs and
determined, on average, how many species were eliminated from the web as a
result. Typically only a small number of species became extinct; in no instance
was the web close to collapse. Next, we examined how the the probability of
extinction of a species depended on its relationship with the deleted species.
This involved the exploration of the concept of indirect predator and prey
species and the extent that the probability of extinction depended on the
trophic level of the two species. The effect of deletions on the web itself was
studied by searching for keystone species, whose removal caused a major
restructuring of the community, and also by looking at the correlation between
a number of food web properties (number of species, linkage density, fraction
of omnivores, degree of cycling and redundancy) and the stability of the web to
deletions. With the exception of redundancy, we found little or no correlation.
In particular, we found no evidence that complexity in terms of increased
species number or links per species is destabilising.
Chinese: 我们使用模型生成的食物网来研究删除物种对网中其他物种以及整个网的影响。该模型包含了现实的种群动态、适应性觅食者以及其他特征，这些特征使得模型食物网与经验性食物网相似。进行了大量模拟，以生成足够多的模型食物网，从而可以在这些网上进行删除实验。我们在四百个不同的模型食物网上删除了每个物种，并平均确定了有多少物种因此从食物网中消失。通常只有少数物种灭绝；在没有任何情况下，食物网接近崩溃。接下来，我们考察了物种灭绝的概率如何取决于其与被删除物种的关系。这涉及到探索间接捕食者和猎物种的概念，以及灭绝概率如何取决于两个物种的营养级。通过寻找关键物种（其移除导致群落发生重大重构）来研究删除对食物网本身的影响，并通过观察一些食物网属性（物种数量、连接密度、杂食性比例、循环程度和冗余度）与食物网对删除的稳定性之间的相关性。除了冗余度之外，我们发现几乎没有或没有相关性。特别是，我们发现没有证据表明，物种数量或每个物种的连接数量增加所带来的复杂性会破坏稳定性。
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English: We present the first analysis of an EUV selected sample of hot DA white
dwarfs using a new type of atmospheric models. These models take into account
the interplay between gravitational settling and radiative acceleration to
predict the chemical stratification from an equilibrium between the two forces
while self-consistently solving for the atmospheric structure. In contrast to
atmospheric models with the assumption of chemical homogeneity, the number of
free parameters in the new models is reduced to the effective temperature and
surface gravity alone. The overall good reproduction of observed EUV spectra
reveals that these models are able to describe the physical conditions in hot
DA white dwarf atmospheres correctly. A comparison with previous analyses
highlights the improvements as well as the limits of our new models.
Chinese: 我们使用一种新型的大气模型对选自EUV的热DA白矮星样本进行了首次分析。这些模型考虑了重力沉降和辐射加速之间的相互作用，通过预测两种力之间的平衡状态下的化学分层来预测大气结构。与假设化学均匀性的大气模型相比，新模型中的自由参数数量仅减少到有效温度和表面重力。观察到的EUV光谱的整体良好再现表明，这些模型能够正确描述热DA白矮星大气中的物理条件。与之前分析的比较突出了我们新模型的改进以及局限性。
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English: We analyze the sequence of polynomials defined by the differential-difference
equation $P_{n+1}(x)=P_{n}^{\prime}(x)+x(n+1)P_{n}(x)$ asymptotically as
$n\to\infty$. The polynomials $P_{n}(x)$ arise in the computation of higher
derivatives of the inverse error function $\operatorname{inverf}(x)$. We use
singularity analysis and discrete versions of the WKB and ray methods and give
numerical results showing the accuracy of our formulas.
Chinese: 我们分析了由微分差分方程 $P_{n+1}(x)=P_{n}^{\prime}(x)+x(n+1)P_{n}(x)$ 定义的多项式序列，当 $n\to\infty$ 时的渐近行为。多项式 $P_{n}(x)$ 出现在计算逆误差函数 $\operatorname{inverf}(x)$ 的高阶导数中。我们使用了奇点分析和离散版本的WKB方法和射线方法，并通过数值结果展示了我们公式的准确性。
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English: The combination of two-dimensional Dirac surface states with s-wave
superconductivity is expected to generate localized topological Majorana zero
modes in vortex cores. Putative experimental signatures of these modes have
been reported for heterostructures of proximitized topological insulators,
iron-based superconductors or certain transition metal dichalcogenides. Despite
these efforts, the Majorana nature of the observed excitation is still under
debate. We propose to identify the presence of Majorana vortex modes using a
nonlocal transport measurement protocol originally employed for one-dimensional
settings. In the case of an isolated subgap state, the protocol provides a
spatial map of the ratio of local charge- and probability-density which offers
a clear distinction between Majorana and ordinary fermionic modes. We show that
these distinctive features survive in the experimentally relevant case of
hybridizing vortex core modes.
Chinese: 二维狄拉克表面态与s波超导性的结合预计会在涡旋核心中产生局域化的拓扑Majorana零模。这些模式的潜在实验特征已在邻近化拓扑绝缘体、铁基超导体或某些过渡金属二硫化物的异质结构中报道。尽管做出了这些努力，观察到的激发的Majorana性质仍然存在争议。我们提议使用最初用于一维设置的局域传输测量协议来识别Majorana涡旋模式的存在。在孤立子隙态的情况下，该协议提供了一个局部电荷密度与概率密度比的空间图，这为Majorana和普通费米子模式提供了清晰的区分。我们表明，这些独特特征在实验相关的混合涡旋核心模式情况下仍然存在。
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English: Optimization models used to make discrete decisions often contain uncertain
parameters that are context-dependent and estimated through prediction. To
account for the quality of the decision made based on the prediction,
decision-focused learning (end-to-end predict-then-optimize) aims at training
the predictive model to minimize regret, i.e., the loss incurred by making a
suboptimal decision. Despite the challenge of the gradient of this loss w.r.t.
the predictive model parameters being zero almost everywhere for optimization
problems with a linear objective, effective gradient-based learning approaches
have been proposed to minimize the expected loss, using the empirical loss as a
surrogate. However, empirical regret can be an ineffective surrogate because
empirical optimal decisions can vary substantially from expected optimal
decisions. To understand the impact of this deficiency, we evaluate the effect
of aleatoric and epistemic uncertainty on the accuracy of empirical regret as a
surrogate. Next, we propose three novel loss functions that approximate
expected regret more robustly. Experimental results show that training two
state-of-the-art decision-focused learning approaches using robust regret
losses improves test-sample empirical regret in general while keeping
computational time equivalent relative to the number of training epochs.
Chinese: 用于做出离散决策的优化模型通常包含上下文相关的未知参数，这些参数通过预测来估计。为了考虑基于预测做出的决策的质量，决策导向学习（端到端预测后优化）旨在训练预测模型以最小化遗憾，即由于做出次优决策而产生的损失。尽管在具有线性目标的优化问题中，关于预测模型参数的损失梯度几乎处处为零，但为了最小化期望损失，已经提出了有效的基于梯度的学习方法，使用经验损失作为代理。然而，经验遗憾可能是无效的代理，因为经验最优决策可能与期望最优决策有很大差异。为了理解这种缺陷的影响，我们评估了经验遗憾作为代理的准确性受到随机性和认识不确定性的影响。接下来，我们提出了三个新的损失函数，这些函数更稳健地近似期望遗憾。实验结果表明，使用稳健遗憾损失训练两个最先进的决策导向学习方法通常可以改进测试样本的经验遗憾，同时保持相对于训练轮次计算时间的等效性。
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English: The symmetric group $\mathsf{S}_n$ and the partition algebra
$\mathsf{P}_k(n)$ centralize one another in their actions on the $k$-fold
tensor power $\mathsf{M}_n^{\otimes k}$ of the $n$-dimensional permutation
module $\mathsf{M}_n$ of $\mathsf{S}_n$. The duality afforded by the commuting
actions determines an algebra homomorphism $\Phi_{k,n}: \mathsf{P}_k(n) \to
\mathsf{End}_{\mathsf{S}_n}(\mathsf{M}_n^{\otimes k})$ from the partition
algebra to the centralizer algebra
$\mathsf{End}_{\mathsf{S}_n}(\mathsf{M}_n^{\otimes k})$, which is a surjection
for all $k, n \in \mathbb{Z}_{\ge 1}$, and an isomorphism when $n \ge 2k$. We
present results that can be derived from the duality between $\mathsf{S}_n$ and
$\mathsf{P}_k(n)$; for example, (i) expressions for the multiplicities of the
irreducible $\mathsf{S}_n$-summands of $\mathsf{M}_n^{\otimes k}$, (ii)
formulas for the dimensions of the irreducible modules for the centralizer
algebra $\mathsf{End}_{\mathsf{S}_n}(\mathsf{M}_n^{\otimes k})$, (iii) a
bijection between vacillating tableaux and set-partition tableaux, (iv)
identities relating Stirling numbers of the second kind and the number of fixed
points of permutations, and (v) character values for the partition algebra
$\mathsf{P}_k(n)$. When $2k >n$, the map $\Phi_{k,n}$ has a nontrivial kernel
which is generated as a two-sided ideal by a single idempotent. We describe the
kernel and image of $\Phi_{k,n}$ in terms of the orbit basis of
$\mathsf{P}_k(n)$ and explain how the surjection $\Phi_{k,n}$ can also be used
to obtain the fundamental theorems of invariant theory for the symmetric group.
Chinese: 对称群 $\mathsf{S}_n$ 和划分代数 $\mathsf{P}_k(n)$ 在它们对 $\mathsf{S}_n$ 的 $n$ 维排列模块 $\mathsf{M}_n$ 的 $k$ 重张量幂 $\mathsf{M}_n^{\otimes k}$ 的作用中相互中心化。由交换作用提供的对偶性确定了一个从划分代数到中心化代数 $\mathsf{End}_{\mathsf{S}_n}(\mathsf{M}_n^{\otimes k})$ 的代数同态 $\Phi_{k,n}: \mathsf{P}_k(n) \to \mathsf{End}_{\mathsf{S}_n}(\mathsf{M}_n^{\otimes k})$，对于所有 $k, n \in \mathbb{Z}_{\ge 1}$，这是一个满射，当 $n \ge 2k$ 时是一个同构。我们展示了可以从 $\mathsf{S}_n$ 和 $\mathsf{P}_k(n)$ 之间的对偶性推导出的结果；例如，（i）$\mathsf{M}_n^{\otimes k}$ 的不可约 $\mathsf{S}_n$-和式的重数表达式，（ii）中心化代数 $\mathsf{End}_{\mathsf{S}_n}(\mathsf{M}_n^{\otimes k})$ 的不可约模的维数公式，（iii）摆荡表格和集合划分表格之间的双射，（iv）与第二类斯特林数和排列的固定点数相关的恒等式，以及（v）划分代数 $\mathsf{P}_k(n)$ 的特征值。当 $2k > n$ 时，映射 $\Phi_{k,n}$ 有一个非平凡核，该核由一个单一的幂等元生成的双边理想。我们用 $\mathsf{P}_k(n)$ 的轨道基来描述 $\Phi_{k,n}$ 的核和像，并解释如何使用满射 $\Phi_{k,n}$ 来获得对称群的不变量理论的基本定理。
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English: We perform a long-term simulation of star and disk formation using
three-dimensional non-ideal magnetohydrodynamics. The simulation starts from a
prestellar cloud and proceeds through the long-term evolution of the
circumstellar disk until $\sim 1.5\times10^5$ yr after protostar formation. The
disk has size $\lesssim 50$ au and little substructure in the main accretion
phase because of the action of magnetic braking and the magnetically-driven
outflow to remove angular momentum. The main accretion phase ends when the
outflow breaks out of the cloud, causing the envelope mass to decrease rapidly.
The outflow subsequently weakens as the mass accretion rate also weakens. While
the envelope-to-disk accretion continues, the disk grows gradually and develops
transient spiral structures due to gravitational instability. When the
envelope-to-disk accretion ends, the disk becomes stable and reaches a size
$\gtrsim 300$ au. In addition, about 30% of the initial cloud mass has been
ejected by the outflow. A significant finding of this work is that after the
envelope dissipates, a revitalization of the wind occurs, and there is mass
ejection from the disk surface that lasts until the end of the simulation. This
mass ejection (or disk wind) is generated since the magnetic pressure
significantly dominates both the ram pressure and thermal pressure above and
below the disk at this stage. Using the angular momentum flux and mass loss
rate estimated from the disk wind, the disk dissipation timescale is estimated
to be $\sim10^6$ yr.
Chinese: 我们使用三维非理想磁流体动力学方法对恒星和盘的形成进行长期模拟。模拟从原恒星云开始，经过围绕恒星的盘的长期演化，直到原恒星形成后约 $1.5\times10^5$ 年。该盘的尺寸小于 $50$ 天文单位，并且在主要吸积阶段由于磁制动和磁驱动喷流的作用以去除角动量，因此几乎没有亚结构。当喷流突破云层时，主要吸积阶段结束，导致包层质量迅速减少。随后，随着吸积率的减弱，喷流也减弱。在包层到盘的吸积持续进行时，盘逐渐增长，并由于引力不稳定性发展出瞬态螺旋结构。当包层到盘的吸积结束时，盘变得稳定，并达到尺寸大于 $300$ 天文单位。此外，大约 30% 的初始云质量被喷流喷射出去。这项工作的一个重要发现是，在包层消散后，风重新焕发生机，并且盘面有物质喷射，持续到模拟结束。这种物质喷射（或盘风）的产生是因为在这个阶段，磁压显著主导了盘上下方的动压和热压。利用从盘风中估计的角动量通量和质量损失率，盘消散的时间尺度估计为 $\sim10^6$ 年。
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English: We report magnetic and transport properties of a new quaternary borocarbide
PrRh$_{2}$B$_{2}$C, based on magnetisation, resistivity and specific heat
studies. This compound forms in LuNi$_{2}$B$_{2}$C-type tetragonal structure
(space group {\it I4/mmm}) and does not exhibit magnetic ordering or
superconductivity down to 0.5 K. The crystal field analysis of specific heat
data suggests a singlet ground state in this compound. The high value of the
Sommerfeld coefficient, $\gamma$ $\approx$ 250 mJ/mole K$^{2}$, together with a
singlet ground state suggests that the heavy fermion behaviour in
PrRh$_{2}$B$_{2}$C results from the interaction of the conduction electrons
with the low lying crystal field excitations. No signature of magnetic ordering
or superconductivity is observed in PrRh$_{2}$B$_{2}$C under the application of
pressure up to 23 kbar.
Chinese: 我们基于磁化强度、电阻率和比热容研究，报道了一种新的四元硼碳化物PrRh$_{2}$B$_{2}$C的磁性和输运性质。该化合物形成于LuNi$_{2}$B$_{2}$C型的四方结构（空间群{\it I4/mmm}），并且在0.5 K以下不表现出磁序或超导性。比热容数据的晶体场分析表明该化合物具有单重基态。Sommerfeld系数的高值，$\gamma$ $\approx$ 250 mJ/mole K$^{2}$，结合单重基态，表明PrRh$_{2}$B$_{2}$C中的重费米子行为是由导带电子与低能晶体场激发的相互作用引起的。在高达23 kbar的压力下，PrRh$_{2}$B$_{2}$C中未观察到磁序或超导性的迹象。
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English: In condensed matter, it is often difficult to untangle the effects of
competing interactions, and this is especially problematic for superconductors.
Quantum simulators may help: here we show how exploiting the properties of
highly excited Rydberg states of cold fermionic atoms in a bilayer lattice can
simulate electron-phonon interactions in the presence of strong correlation - a
scenario found in many unconventional superconductors. We discuss the core
features of the simulator, and use numerics to compare with condensed matter
analogues. Finally, we illustrate how to achieve a practical, tunable
implementation of the simulation using painted spot potentials.
Chinese: 在凝聚态物质中，通常很难区分相互竞争的相互作用的影响，这对于超导体来说尤其成问题。量子模拟器可能有所帮助：在这里，我们展示了如何利用双层晶格中冷费米子原子的激发态Rydberg态的性质来模拟强关联存在下的电子-声子相互作用——这种情况在许多非常规超导体中都有发现。我们讨论了模拟器的核心特征，并使用数值方法与凝聚态物质类似物进行比较。最后，我们说明了如何使用涂漆点势来实现一个实用、可调的模拟。
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English: The eruption of the recurrent nova U Scorpii on 28 January 2010 is now the
all-time best observed nova event. We report 36,776 magnitudes throughout its
67 day eruption, for an average of one measure every 2.6 minutes. This unique
and unprecedented coverage is the first time that a nova has any substantial
amount of fast photometry. With this, two new phenomena have been discovered:
the fast flares in the early light curve seen from days 9-15 (which have no
proposed explanation) and the optical dips seen out of eclipse from days 41-61
(likely caused by raised rims of the accretion disk occulting the bright inner
regions of the disk as seen over specific orbital phases). The expanding shell
and wind cleared enough from days 12-15 so that the inner binary system became
visible, resulting in the sudden onset of eclipses and the turn-on of the
supersoft X-ray source. On day 15, a strong asymmetry in the out-of-eclipse
light points to the existence of the accretion stream. The normal optical
flickering restarts on day 24.5. For days 15-26, eclipse mapping shows that the
optical source is spherically symmetric with a radius of 4.1 R_sun. For days
26-41, the optical light is coming from a rim-bright disk of radius 3.4 R_sun.
For days 41-67, the optical source is a center-bright disk of radius 2.2 R_sun.
Throughout the eruption, the colors remain essentially constant. We present 12
eclipse times during eruption plus five just after the eruption.
Chinese: 2010年1月28日， recurrent nova U Scorpii的爆发现在是观测到的最佳新星事件。我们报告了其67天爆发期间的36,776个光度值，平均每2.6分钟测量一次。这种独特且前所未有的覆盖范围是首次有新星拥有大量快速光度的观测数据。因此，发现了两种新的现象：从第9天到第15天早期光曲线中看到的快速爆发（目前没有提出解释）以及从第41天到第61天日食外看到的视亮度下降（可能是由于吸积盘边缘抬升，遮挡了在特定轨道相位中看到的明亮内区域）。从第12天到第15天，膨胀的壳层和风清除得足够多，以至于内双星系统变得可见，导致日食突然开始，并开启了超软X射线源。在第15天，日食外的光强不对称性指向了吸积流的存。正常的光闪烁在第24.5天重新开始。对于第15天到第26天，日食映射显示光学源是球对称的，半径为4.1个太阳半径。对于第26天到第41天，光学光来自半径为3.4个太阳半径的边缘明亮盘。对于第41天到第67天，光学源是一个中心明亮盘，半径为2.2个太阳半径。在整个爆发过程中，颜色保持基本恒定。我们展示了爆发期间加爆发后五次的12次日食时间。
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English: Representing a manifold of very high-dimensional data with generative models
has been shown to be computationally efficient in practice. However, this
requires that the data manifold admits a global parameterization. In order to
represent manifolds of arbitrary topology, we propose to learn a mixture model
of variational autoencoders. Here, every encoder-decoder pair represents one
chart of a manifold. We propose a loss function for maximum likelihood
estimation of the model weights and choose an architecture that provides us the
analytical expression of the charts and of their inverses. Once the manifold is
learned, we use it for solving inverse problems by minimizing a data fidelity
term restricted to the learned manifold. To solve the arising minimization
problem we propose a Riemannian gradient descent algorithm on the learned
manifold. We demonstrate the performance of our method for low-dimensional toy
examples as well as for deblurring and electrical impedance tomography on
certain image manifolds.
Chinese: 使用生成模型表示非常高维的数据在实践中被证明是计算效率高的。然而，这要求数据流形能够接受全局参数化。为了表示任意拓扑的流形，我们提出学习一个变分自编码器的混合模型。在这里，每个编码器-解码器对代表流形的一个图表。我们提出一个损失函数用于模型权重的最大似然估计，并选择一个能够提供图表及其逆的解析表达式的架构。一旦流形被学习，我们使用它通过最小化限制在所学习流形上的数据保真项来解决逆问题。为了解决出现的最小化问题，我们提出在所学习流形上的黎曼梯度下降算法。我们展示了我们的方法在低维玩具示例以及某些图像流形上的去模糊和电阻抗断层扫描中的性能。
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English: Supervised machine learning and predictive models have achieved an impressive
standard today, enabling us to answer questions that were inconceivable a few
years ago. Besides these successes, it becomes clear, that beyond pure
prediction, which is the primary strength of most supervised machine learning
algorithms, the quantification of uncertainty is relevant and necessary as
well. However, before quantification is possible, types and sources of
uncertainty need to be defined precisely. While first concepts and ideas in
this direction have emerged in recent years, this paper adopts a conceptual,
basic science perspective and examines possible sources of uncertainty. By
adopting the viewpoint of a statistician, we discuss the concepts of aleatoric
and epistemic uncertainty, which are more commonly associated with machine
learning. The paper aims to formalize the two types of uncertainty and
demonstrates that sources of uncertainty are miscellaneous and can not always
be decomposed into aleatoric and epistemic. Drawing parallels between
statistical concepts and uncertainty in machine learning, we emphasise the role
of data and their influence on uncertainty.
Chinese: 监督机器学习和预测模型今天已达到令人印象深刻的水平，使我们能够回答几年前还难以想象的问题。除了这些成功之外，人们逐渐认识到，除了纯粹的预测（这是大多数监督机器学习算法的主要优势）之外，不确定性的量化同样重要且必要。然而，在量化不确定性之前，需要精确定义不确定性的类型和来源。虽然近年来在这一方向上已经出现了初步概念和想法，但本文采用概念性基础科学视角，考察了可能的不确定性来源。通过采用统计学家视角，我们讨论了与机器学习更相关的偶然不确定性和认知不确定性这两个概念。本文旨在形式化这两种不确定性类型，并证明不确定性来源是多样的，并不总是可以分解为偶然不确定性和认知不确定性。通过在统计概念和机器学习中的不确定性之间建立类比，我们强调了数据的作用及其对不确定性的影响。
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English: The Tribonacci sequence is a well-known example of third order recurrence
sequence, which belongs to a particular class of recursive sequences. In this
article, other generalized Tribonacci sequence is introduced and defined by
$H_{n+2}=H_{n+1}+H_{n}+H_{n-1}\ \ (n\geq 1)$, where $H_{0}=3$, $H_{1}=0$ and
$H_{2}=2$. Also $n$-th power of the generating matrix for this generalized
Tribonacci sequence is established and some basic properties of this sequence
are obtained by matrix methods. There are many elementary formulae relating the
various $H_{n}$, most of which, since the sequence is defined inductively, are
themselves usually proved by induction.
Chinese: 三阶递推序列的一个著名例子是Tribonacci序列，它属于递归序列的一个特定类别。在本文中，介绍了其他广义的Tribonacci序列，并定义为$H_{n+2}=H_{n+1}+H_{n}+H_{n-1}\ \ (n\geq 1)$，其中$H_{0}=3$，$H_{1}=0$和$H_{2}=2$。此外，还建立了这个广义Tribonacci序列生成矩阵的$n$次幂，并利用矩阵方法获得了该序列的一些基本性质。存在许多与各种$H_{n}$相关的基本公式，其中大多数由于序列是递归定义的，通常也通过归纳法来证明。
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English: In recent years, fuzz testing has proven itself to be one of the most
effective techniques for finding correctness bugs and security vulnerabilities
in practice. One particular fuzz testing tool, American Fuzzy Lop or AFL, has
become popular thanks to its ease-of-use and bug-finding power. However, AFL
remains limited in the depth of program coverage it achieves, in particular
because it does not consider which parts of program inputs should not be
mutated in order to maintain deep program coverage. We propose an approach,
FairFuzz, that helps alleviate this limitation in two key steps. First,
FairFuzz automatically prioritizes inputs exercising rare parts of the program
under test. Second, it automatically adjusts the mutation of inputs so that the
mutated inputs are more likely to exercise these same rare parts of the
program. We conduct evaluation on real-world programs against state-of-the-art
versions of AFL, thoroughly repeating experiments to get good measures of
variability. We find that on certain benchmarks FairFuzz shows significant
coverage increases after 24 hours compared to state-of-the-art versions of AFL,
while on others it achieves high program coverage at a significantly faster
rate.
Chinese: 近年来，模糊测试已被证明是实践中发现正确性错误和安全漏洞最有效的技术之一。一款特定的模糊测试工具，美国模糊跳蚤或AFL，因其易用性和强大的错误发现能力而变得流行。然而，AFL在达到的程序覆盖率深度方面仍然有限，尤其是在它没有考虑哪些程序输入部分不应该变异以保持深度的程序覆盖率。我们提出了一种方法，称为FairFuzz，通过两个关键步骤帮助缓解这种限制。首先，FairFuzz自动优先处理测试程序中罕见部分的输入。其次，它自动调整输入的变异，使得变异后的输入更有可能执行这些相同的罕见程序部分。我们对现实世界的程序进行了评估，与AFL的最新版本进行了比较，彻底重复实验以获得良好的可变性度量。我们发现，在某些基准测试中，与AFL的最新版本相比，FairFuzz在24小时后显示出显著的覆盖率增加，而在其他基准测试中，它以显著更快的速度实现了高程序覆盖率。
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English: We discuss a relationship between Chern-Schwartz-MacPherson classes for
Schubert cells in flag manifolds, Fomin-Kirillov algebra, and the generalized
nil-Hecke algebra. We show that nonnegativity conjecture in Fomin-Kirillov
algebra implies the nonnegativity of the Chern-Schwartz-MacPherson classes for
Schubert cells in flag manifolds for type A. Motivated by this connection, we
also prove that the (equivariant) Chern-Schwartz-MacPherson classes for
Schubert cells in flag manifolds are certain summations of the structure
constants of the equivariant cohomology of the Bott-Samelson varieties. We also
discuss the refined positivity conjectures of the Chern-Schwartz-MacPherson
classes for Schubert cells motivated by the nonnegativity conjecture in
Fomin-Kirillov algebra.
Chinese: 我们讨论了旗流形中舒伯特胞的陈-施瓦茨-麦克弗森类、福明-基里洛夫代数以及广义拟Hecke代数之间的关系。我们证明了福明-基里洛夫代数中的非负猜想意味着A型的旗流形中舒伯特胞的陈-施瓦茨-麦克弗森类具有非负性。受此联系的启发，我们还证明了旗流形中舒伯特胞的（等变）陈-施瓦茨-麦克弗森类是博特-萨梅尔森簇的等变上同调的结构常数的某种和。我们还讨论了受福明-基里洛夫代数中的非负猜想启发的、陈-施瓦茨-麦克弗森类对舒伯特胞的精细化正性猜想。
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English: A failed core-collapse supernova from a non-rotating progenitor can eject
mass due to a weakening of gravity associated to neutrino emission by the
protoneutron star. This mechanism yields observable transients and sets an
upper limit to the mass of the black hole (BH) remnant. Previous global
simulations of this mechanism have included neutrino losses parametrically,
however, with direct implications for the ejecta mass and energy. Here we
evolve the inner supernova core with a spherically-symmetric,
general-relativistic neutrino radiation-hydrodynamic code until BH formation.
We then use the result in a Newtonian code that follows the response of the
outer layers of the star to the change in gravity and resolves the surface
pressure scale height. We find that the dense-matter equation of state (EOS)
can introduce a factor $\sim 2$ variation in gravitational mass lost to
neutrinos, with a stiff EOS matching previous parametric results, and a soft
EOS yielding lower ejecta masses and energies by a factor of several. This
difference is caused primarily by the longer time to BH formation in stiffer
EOSs. With a soft EOS, our red and yellow supergiant progenitors fail to unbind
mass if hydrogen recombination energy is not included. Using a linear ramp in
time for mass-energy lost to neutrinos (with suitable parameters) yields a
stellar response within $\sim 10\%$ of that obtained using the detailed history
of neutrino losses. Our results imply quantitative but not qualitative
modifications to previous predictions for shock breakout, plateau emission, and
final BH masses from these events.
Chinese: 一个由非旋转的祖先恒星产生的失败的核塌缩超新星，由于原中子星中微子发射导致的引力减弱，可以喷射质量。这种机制产生了可观测的短暂现象，并设定了黑洞（BH）残留物质量的上限。以前对这种机制的全球模拟已经参数化地包括了中微子损失，然而这对喷射质量和能量有直接影响。在这里，我们使用一个球对称的、广义相对论的中微子辐射流体动力学代码，直到黑洞形成，来演化超新星核心的内层。然后我们使用牛顿力学代码，该代码追踪星体外层对重力变化的响应，并解析表面压力尺度高度。我们发现，致密物质状态方程（EOS）可以引入一个约2倍的引力质量损失到中微子的变化因子，一个刚性EOS与先前的参数化结果相匹配，而一个软EOS通过几个因子的方式产生较低的喷射质量和能量。这种差异主要是由刚性EOS中黑洞形成所需时间更长引起的。使用软EOS时，我们的红超巨星和黄超巨星祖先如果不含氢再结合能量，则无法解绑质量。使用一个随时间线性增加的中微子损失质量-能量（具有合适的参数），可以得到与使用中微子损失详细历史相比的恒星响应，误差在约10%以内。我们的结果意味着对先前预测的冲击突破、平台发射和这些事件最终黑洞质量进行了定量但非定性的修改。
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English: New constraints are found that must necessarily hold for Israel-Stewart-like
theories of fluid dynamics to be causal far away from equilibrium. Conditions
that are sufficient to ensure causality, local existence, and uniqueness of
solutions in these theories are also presented. Our results hold in the full
nonlinear regime, taking into account bulk and shear viscosities (at zero
chemical potential), without any simplifying symmetry or near-equilibrium
assumptions. Our findings provide fundamental constraints on the magnitude of
viscous corrections in fluid dynamics far from equilibrium.
Chinese: 新的约束条件被发现，这些条件对于以色列-斯图尔特流体动力学理论在远离平衡状态下保持因果性是必须满足的。确保这些理论中因果性、解的局部存在性和唯一性的充分条件也被提出。我们的结果在完全的非线性状态下成立，考虑了体积和剪切粘度（在零化学势下），没有任何简化的对称性或近平衡假设。我们的发现为远离平衡的流体动力学中粘度校正的幅度提供了基本约束。
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English: The original ideas of Cooper and Dryden, that allosteric signalling can be
induced between distant binding sites on proteins without any change in mean
structural conformation, has proved to be a remarkably prescient insight into
the rich structure of protein dynamics. It represents an alternative to the
celebrated Monod-Wyman-Changeux mechanism and proposes that modulation of the
amplitude of thermal fluctuations around a mean structure, rather than shifts
in the structure itself, give rise to allostery in ligand binding. In a
complementary approach to experiments on real proteins, here we take a
theoretical route to identify the necessary structural components of this
mechanism. By reviewing and extending an approach that moves from very
coarse-grained to more detailed models, we show that, a fundamental requirement
for a body supporting fluctuation-induced allostery is a strongly inhomogeneous
elastic modulus. This requirement is reflected in many real proteins, where a
good approximation of the elastic structure maps strongly coherent domains onto
rigid blocks connected by more flexible interface regions.
Chinese: Cooper和Dryden的原始观点——即无需平均结构构象发生任何变化，蛋白质上远距离结合位点之间即可诱导变构信号传导——已被证明是对蛋白质动力学丰富结构的极具远见的洞察。它代表了一种替代著名的Monod-Wyman-Changeux机制的方案，并提出：围绕平均结构的温度涨落幅度的调节，而非结构本身的位移，导致了配体结合的变构效应。在补充真实蛋白质实验的方法中，我们通过理论途径来确定该机制所必需的结构成分。通过回顾并扩展从非常粗粒化模型到更详细模型的方法，我们表明，支持涨落诱导变构效应的实体必须具备强非均匀弹性模量这一基本要求。这一要求在许多真实蛋白质中得到了体现，其中弹性结构的良好近似将强相干区域映射到由更柔性的界面区域连接的刚性块上。
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English: We present an idiosyncratic view of the race for quantum computational
supremacy. Google's approach and IBM challenge are examined. An unexpected
side-effect of the race is the significant progress in designing fast classical
algorithms. Quantum supremacy, if achieved, won't make classical computing
obsolete.
Chinese: 我们提出了一种对量子计算优越性的竞赛的独特看法。谷歌的方法和IBM的挑战被进行了分析。竞赛的一个出乎意料的副作用是设计快速经典算法的显著进步。如果实现了量子优越性，它并不会使经典计算过时。
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English: We show that every Banach space in which weakly compact sets are super weakly
compact in automatically weakly sequentially complete answering a question by
Silber (2024). In the proof we show how to build a weakly compact set which is
not super weakly compact from an arbitrary nontrivial weakly Cauchy sequence
using the notion of a summing subsequence of Rosenthal or Singer.
Chinese: 我们证明了在任意一个Banach空间中，如果弱紧集是超弱紧的，那么该空间自动是弱序列完备的，这回答了Silber（2024）的一个问题。在证明过程中，我们展示了如何通过Rosenthal或Singer提出的求和子序列的概念，从一个任意的非平凡弱收敛序列中构造出一个既弱紧又不是超弱紧的集合。
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English: Particle acceleration in collisionless astrophysical shocks, i.e., diffusive
shock acceleration (DSA), is the most likely mechanism for producing cosmic
rays, at least below 10^{15} eV. Despite the success of this theory, several
key elements, including the injection of thermal particles, remains poorly
understood. We investigate injection in strongly nonlinear shocks by comparing
a semi-analytic model of DSA with a Monte Carlo model. These two models treat
injection quite differently and we show, for a particular set of parameters,
how these differences influence the overall acceleration efficiency and the
shape of the broad-band distribution function.
Chinese: 碰撞无粒子天体物理学冲击中的粒子加速，即扩散性冲击加速（DSA），是产生宇宙射线最可能的机制，至少在10^15 eV以下。尽管这一理论取得了成功，但仍有几个关键元素，包括热粒子的注入，理解不足。我们通过对比一个半解析的DSA模型与一个蒙特卡洛模型来研究注入问题。这两个模型对注入的处理方式截然不同，我们展示了，对于一组特定的参数，这些差异如何影响整体加速效率和宽带分布函数的形态。
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English: Using two alternative [O/H]-[Fe/H] dependences, the empirical oxygen
abundance distribution (EGD) is deduced from two different samples of old
objects, available in the literature. Under the assumption that each
distribution (with the addition of a third one previously known) is typical for
the corresponding subsystem, the EGD of the Galactic spheroid is determined
weighting by mass. A fit to the data is provided by simple models of chemical
evolution implying both homogeneous and inhomogeneous mixing, where star
formation is inhibited during halo formation and enhanced during bulge
formation, with respect to the disk. The theoretical oxygen abundance
distribution (TGD) is first determined for the halo and the bulge separately,
and then for the Galactic spheroid weighting by mass. Simple models implying
inhomogeneous mixing are able to fit an empirical age-metallicity relation
(EAMR) recently determined from a homogeneous sample of globular clusters,
which shows a non monotonic trend characterized by large dispersion. Some
possible implications related to the formation of Galactic spheroid and disk
are also discussed.
Chinese: 利用两种[O/H]-[Fe/H]的替代依赖关系，从文献中可用的两种不同样本的老天体中推导出经验性的氧丰度分布（EGD）。在假设每个分布（加上先前已知的第三个分布）对应于相应的子系统是典型的前提下，通过质量加权确定了银河球状星系的EGD。简单的化学演化模型，暗示着化学混合既均匀又非均匀，其中在晕形成期间恒星形成受到抑制，在球状形成期间恒星形成得到增强，相对于盘而言，可以很好地拟合最近从同质样本球状星团中确定的经验年龄金属丰度关系（EAMR），该关系显示出非单调趋势，特征为较大的分散性。还讨论了与银河球状星系和盘形成相关的可能含义。
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English: Recent developments in post-Minkowksian (PM) calculations have led to a
fast-growing body of weak-field perturbative information. As such, there is
major interest within the gravitational wave community as to how this
information can be used to improve the accuracy of theoretical waveform models.
In this work, we build on recent efforts to validate high-order PM calculations
using numerical relativity simulations. We present a new set of high-energy
scattering simulations for equal-mass, non-spinning binary black holes, further
expanding the existing suite of NR simulations. We outline the basic features
of three recently proposed resummation schemes (the $\mathscr{L}$-resummed
model, the $w^\mathrm{eob}$ model and the SEOB-PM model) and compare the
analytical predictions to our NR data. Each model is shown to demonstrate
pathological behaviour at high energies, with common features such as PM
hierarchical shifts and divergences. The NR data can also be used to calibrate
pseudo-5PM corrections to the scattering angle or EOB radial potentials. In
each case, we argue that including higher-order information improves the
agreement between the analytical models and NR, though the extent of
improvement depends on how this information is incorporated and the choice of
analytical baseline. Finally, we demonstrate that further resummation of the
EOB radial potentials could be an effective strategy to improving the model
agreement.
Chinese: 近期在后米氏（PM）计算领域的发展，催生了大量弱场微扰信息。因此，引力波领域对此表示高度关注，探讨如何利用这些信息提升理论波形模型的精度。本研究基于近期利用数值相对论模拟验证高阶PM计算的努力展开。我们展示了一组针对等质量、非自旋双黑洞的高能散射模拟，进一步扩充了现有的数值相对论（NR）模拟系列。我们概述了三种近期提出的求和方案（$\mathscr{L}$-求和模型、$w^\mathrm{eob}$模型和SEOB-PM模型）的基本特征，并将解析预测与我们的NR数据进行了比较。结果显示，每个模型在高能区均表现出病态行为，具有公有的特征，如PM层级偏移和发散。NR数据还可用于校准散射角或EOB径向势的伪5PM修正。在每种情况下，我们认为包含更高阶信息能提升解析模型与NR数据的吻合度，但改善程度取决于信息整合方式和解析基准的选择。最后，我们证明进一步对EOB径向势进行求和可能是提升模型吻合度的有效策略。
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English: Matrix completion is the study of recovering an underlying matrix from a
sparse subset of noisy observations. Traditionally, it is assumed that the
entries of the matrix are "missing completely at random" (MCAR), i.e., each
entry is revealed at random, independent of everything else, with uniform
probability. This is likely unrealistic due to the presence of "latent
confounders", i.e., unobserved factors that determine both the entries of the
underlying matrix and the missingness pattern in the observed matrix. For
example, in the context of movie recommender systems -- a canonical application
for matrix completion -- a user who vehemently dislikes horror films is
unlikely to ever watch horror films. In general, these confounders yield
"missing not at random" (MNAR) data, which can severely impact any inference
procedure that does not correct for this bias. We develop a formal causal model
for matrix completion through the language of potential outcomes, and provide
novel identification arguments for a variety of causal estimands of interest.
We design a procedure, which we call "synthetic nearest neighbors" (SNN), to
estimate these causal estimands. We prove finite-sample consistency and
asymptotic normality of our estimator. Our analysis also leads to new
theoretical results for the matrix completion literature. In particular, we
establish entry-wise, i.e., max-norm, finite-sample consistency and asymptotic
normality results for matrix completion with MNAR data. As a special case, this
also provides entry-wise bounds for matrix completion with MCAR data. Across
simulated and real data, we demonstrate the efficacy of our proposed estimator.
Chinese: 矩阵补全是指从一组稀疏的、带有噪声的观察数据中恢复出一个潜在矩阵的研究。传统上，我们假设矩阵的每个元素都是“完全随机缺失”（MCAR），即每个元素是随机揭示的，与其它任何因素无关，且概率分布均匀。然而，由于存在“潜在混淆因素”，即那些既决定了潜在矩阵的元素又决定了观察矩阵中缺失模式的无观测因素，这种假设可能是不切实际的。例如，在电影推荐系统这一矩阵补全的经典应用场景中，一个强烈不喜欢恐怖片的用户几乎不可能去看恐怖片。一般而言，这些混淆因素会导致“非随机缺失”（MNAR）数据，这可能会严重影响到任何未校正偏差的推断过程。我们通过潜在结果的语言构建了一个矩阵补全的正式因果模型，并为各种感兴趣的因果量提供了新颖的识别论据。我们设计了一个名为“合成最近邻”（SNN）的程序来估计这些因果量。我们证明了我们的估计器在有限样本下的渐近一致性和渐近正态性。我们的分析还为矩阵补全的文献带来了新的理论结果。特别是，我们证明了在存在MNAR数据的情况下，矩阵补全在元素级别，即最大范数下，具有有限样本渐近一致性和渐近正态性。作为一个特例，这还为MCAR数据下的矩阵补全提供了元素级别的界限。在模拟和真实数据中，我们展示了我们提出的估计器的有效性。
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English: In this paper, let $G$ be a Cayley graph of a discrete group of polynomial
growth with homogeneous dimension $N\geq3$. We study the Choquard type equation
on $G$: \begin{equation} \Delta u+(R_{\alpha}\ast\mid u\mid^{p})\mid
u\mid^{p-2}u=0, \end{equation} where $\alpha\in(0,N)$, $p>\frac{N+\alpha}{N-2}$
and $R_{\alpha}$ stands for the Green's function of the discrete fractional
Laplace operator, which has same asymptotics as the Riesz potential. We prove
the discrete Hardy-Littlewood-Sobolev inequality on such Cayley graphs, and by
the discrete Concentration-Compactness principle we prove the existence of
extremal functions for the corresponding Sobolev type inequalities in
supercritical cases, which yields a positive ground state solution of the above
Choquard type equation. Moreover, we obtain positive ground state solutions of
Choquard type equations with $p$-Laplace, biharmonic and $p$-biharmonic
operators etc.
Chinese: 在本文中，设$G$为一个具有齐次维度$N\geq3$的离散群的多项式增长凯莱图。我们研究了$G$上的Choquard类型方程：\begin{equation} \Delta u+(R_{\alpha}\ast\mid u\mid^{p})\mid u\mid^{p-2}u=0, \end{equation} 其中$\alpha\in(0,N)$，$p>\frac{N+\alpha}{N-2}$，且$R_{\alpha}$表示离散分数拉普拉斯算子的格林函数，其渐近性与Riesz势相同。我们证明了此类凯莱图上的离散Hardy-Littlewood-Sobolev不等式，并利用离散集中-紧致性原理证明了在超临界情况下对应Sobolev类型不等式的极值函数的存在性，从而得到了上述Choquard类型方程的正基态解。此外，我们还获得了具有$p$-Laplace算子、双调和算子和$p$-双调和算子等Choquard类型方程的正基态解。
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English: In this paper, we obtain an analytical expression for the vapor pressure of a
paramagnetic solid for high temperatures. We have considered the behavior of
magnetic materials in the presence of an external magnetic field using the
thermodynamical analysis and the elements of statistical mechanics in
microscopic systems. We found that the vapor pressure depends on the magnetic
susceptibility of material and the external field applied.
Chinese: 在这篇论文中，我们得到了高温下顺磁性固体蒸汽压的分析表达式。我们利用热力学分析和微观系统中的统计力学元素，研究了在外部磁场中磁性材料的行为。我们发现，蒸汽压取决于材料的磁化率和施加的外部磁场。
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English: Learning the optimal ordering of content is an important challenge in website
design. The learning to rank (LTR) framework models this problem as a
sequential problem of selecting lists of content and observing where users
decide to click. Most previous work on LTR assumes that the user considers each
item in the list in isolation, and makes binary choices to click or not on
each. We introduce a multinomial logit (MNL) choice model to the LTR framework,
which captures the behaviour of users who consider the ordered list of items as
a whole and make a single choice among all the items and a no-click option.
Under the MNL model, the user favours items which are either inherently more
attractive, or placed in a preferable position within the list. We propose
upper confidence bound (UCB) algorithms to minimise regret in two settings -
where the position dependent parameters are known, and unknown. We present
theoretical analysis leading to an $\Omega(\sqrt{JT})$ lower bound for the
problem, an $\tilde{O}(\sqrt{JT})$ upper bound on regret of the UCB algorithm
in the known-parameter setting, and an $\tilde{O}(K^2\sqrt{JT})$ upper bound on
regret, the first, in the more challenging unknown-position-parameter setting.
Our analyses are based on tight new concentration results for Geometric random
variables, and novel functional inequalities for maximum likelihood estimators
computed on discrete data.
Chinese: 学习内容的最佳排序是网站设计中的一个重要挑战。学习排序（LTR）框架将这个问题建模为选择内容列表的顺序问题，并观察用户在哪里点击。大多数关于LTR的先前工作都假设用户独立地考虑列表中的每个项目，并对每个项目做出点击或不点击的二进制选择。我们向LTR框架引入多项式逻辑（MNL）选择模型，该模型捕捉了将项目有序列表视为整体并从所有项目和“不点击”选项中选择一个的用户行为。在MNL模型下，用户倾向于选择那些本质上更有吸引力或在列表中位置更佳的项目。我们提出了上置信界（UCB）算法来最小化两种设置下的遗憾 - 其中位置相关的参数是已知的和未知的。我们提出了理论分析，导致了问题的 $\Omega(\sqrt{JT})$ 下界，在已知参数设置中对UCB算法遗憾的 $\tilde{O}(\sqrt{JT})$ 上界，以及在更具挑战性的未知位置参数设置中的遗憾的 $\tilde{O}(K^2\sqrt{JT})$ 上界。我们的分析基于对几何随机变量新的紧密集中结果，以及计算在离散数据上的最大似然估计器的创新功能不等式。
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English: The environment within the inner few hundred parsecs of the Milky Way, known
as the "Central Molecular Zone" (CMZ), harbours densities and pressures orders
of magnitude higher than the Galactic Disc; akin to that at the peak of cosmic
star formation (Kruijssen & Longmore 2013). Previous studies have shown that
current theoretical star-formation models under-predict the observed level of
star-formation (SF) in the CMZ by an order of magnitude given the large
reservoir of dense gas it contains. Here we explore potential reasons for this
apparent dearth of star formation activity.
Chinese: 银河系内部数百秒差距范围内的环境，被称为“中心分子区”（CMZ），其密度和压力比银河盘高几个数量级；类似于宇宙恒星形成高峰期的状态（Kruijssen & Longmore 2013）。先前的研究表明，鉴于该区域包含大量密集气体，当前的理论恒星形成模型低估了CMZ中观测到的恒星形成（SF）水平一个数量级。在这里，我们探讨造成这种看似恒星形成活动稀少的原因。
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English: Consider a smooth projective surface $S$. Consider a fibration $S\to C$ where
$C$ is a quasi-projective curve such the fibers are smooth projective curves.
The aim of this text is to show that the kernels of the push-forward
homomorphism $\{j_{t*}\}_{t\in C}$ from the Jacobian $J(C_t)$ to $A_0(S)$ forms
a family in the sense that it is a countable union of translates of an abelian
scheme over $C$ sitting inside the Jacobian scheme $\mathscr{J}\to C$, such
that the fiber of this countable union at $t$ is the kernel of $j_{t*}$.
Chinese: 考虑一个光滑投射曲面 $S$。考虑一个纤维化 $S\to C$，其中 $C$ 是一个拟投射曲线，其纤维是光滑投射曲线。本文的目标是证明从 $J(C_t)$ 到 $A_0(S)$ 的推前同态 $\{j_{t*}\}_{t\in C}$ 的核构成一个族，即它是一个阿贝尔方案在 $C$ 上的平移的可数并集，这个并集位于雅可比簇 $\mathscr{J}\to C$ 内，且在 $t$ 处的纤维是这个可数并集的核。
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English: In the last months, due to the emergency of Covid-19, questions related to
the fact of belonging or not to a particular class of individuals (`infected or
not infected'), after being tagged as `positive' or `negative' by a test, have
never been so popular. Similarly, there has been strong interest in estimating
the proportion of a population expected to hold a given characteristics
(`having or having had the virus'). Taking the cue from the many related
discussions on the media, in addition to those to which we took part, we
analyze these questions from a probabilistic perspective (`Bayesian'),
considering several effects that play a role in evaluating the probabilities of
interest. The resulting paper, written with didactic intent, is rather general
and not strictly related to pandemics: the basic ideas of Bayesian inference
are introduced and the uncertainties on the performances of the tests are
treated using the metrological concepts of `systematics', and are propagated
into the quantities of interest following the rules of probability theory; the
separation of `statistical' and `systematic' contributions to the uncertainty
on the inferred proportion of infectees allows to optimize the sample size; the
role of `priors', often overlooked, is stressed, however recommending the use
of `flat priors', since the resulting posterior distribution can be `reshaped'
by an `informative prior' in a later step; details on the calculations are
given, also deriving useful approximated formulae, the tough work being however
done with the help of direct Monte Carlo simulations and Markov Chain Monte
Carlo, implemented in R and JAGS (relevant code provided in appendix).
Chinese: 在过去的几个月里，由于新冠疫情的紧急情况，关于是否属于特定个体类别（“感染或未感染”）的问题，在经过测试被标记为“阳性”或“阴性”之后，从未如此流行。同样，人们对估计预期具有特定特征（“感染过或曾感染病毒”）的人口比例表现出浓厚的兴趣。从媒体上许多相关讨论以及我们参与的讨论中汲取灵感，我们从概率论（“贝叶斯”）的角度分析了这些问题，考虑了在评估感兴趣的概率时起作用的几个效应。由此产生的论文，具有教学目的，相当通用，并不严格与流行病相关：介绍了贝叶斯推理的基本思想，并使用计量学概念“系统误差”来处理测试性能的不确定性，并按照概率论规则传播到感兴趣的量上；通过将“统计”和“系统”对推断感染者比例的不确定性的贡献分开，可以优化样本量；强调了通常被忽视的“先验”的作用，然而推荐使用“平坦先验”，因为后续步骤可以通过“信息先验”来“重塑”得到的后验分布；给出了计算细节，也推导出有用的近似公式，但艰苦的工作是在R和JAGS（相关代码在附录中提供）的直接蒙特卡洛模拟和马尔可夫链蒙特卡洛的帮助下完成的。
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English: We point out a natural mechanism for quenching of star formation in
early-type galaxies. It automatically links the color of a galaxy with its
morphology and does not require gas consumption, removal or termination of gas
supply. Given that star formation takes place in gravitationally unstable gas
disks, it can be quenched when a disk becomes stable against fragmentation to
bound clumps. This can result from the growth of a stellar spheroid, for
instance by mergers. We present the concept of morphological quenching (MQ)
using standard disk instability analysis, and demonstrate its natural
occurrence in a cosmological simulation using an efficient zoom-in technique.
We show that the transition from a stellar disk to a spheroid can be sufficient
to stabilize the gas disk, quench star formation, and turn an early-type galaxy
red and dead while gas accretion continues. The turbulence necessary for disk
stability can be stirred up by sheared perturbations within the disk in the
absence of bound star-forming clumps. While gas stripping processes are limited
to dense groups and clusters, and other quenching mechanisms like AGN feedback,
virial shock heating and gravitational heating, are limited to halos more
massive than 10^12 Mo, the MQ can explain the appearance of red ellipticals
even in less massive halos and in the field. The dense gas disks observed in
some of today's red ellipticals may be the relics of this mechanism, whereas
red galaxies with quenched gas disks are expected to be more frequent at high
redshift.
Chinese: 我们指出了一种早期型星系中星系形成熄灭的自然机制。它自动将星系的颜色与其形态联系起来，并且不需要消耗气体、移除或终止气体供应。鉴于星系形成发生在引力不稳定的气体盘中，当盘变得稳定以防止碎裂成束缚团块时，星系形成就会熄灭。这可能是由恒星球状体的增长导致的，例如通过合并。我们提出了形态熄灭（MQ）的概念，使用标准的盘不稳定性分析，并使用有效的放大技术演示了其在宇宙学模拟中的自然发生。我们表明，从恒星盘到球状体的转变足以稳定气体盘，熄灭星系形成，并使早期型星系变红和死亡，而气体吸积持续进行。在没有束缚星系形成团块的情况下，可以通过盘内的剪切扰动引起必要的湍流以维持盘的稳定性。虽然气体剥离过程仅限于密集的群和星系团，而其他熄灭机制如活动星系核反馈、virial冲击加热和引力加热则仅限于质量大于10^12 Mo的晕，但MQ可以解释即使在质量较小的晕和星系场中红椭圆星系的产生。今天观察到的某些红椭圆星系中的密集气体盘可能是这种机制的遗迹，而预计在较高红移处的红椭圆星系中具有熄灭气体盘的星系将更为常见。
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English: In this note, we consider the dynamics associated to an epsilon-perturbation
of an integrable Hamiltonian system in action-angle coordinates in any number
of degrees of freedom and we prove the following result of "micro-diffusion":
under generic assumptions on h and f , there exists an orbit of the system for
which the drift of its action variables is at least of order square root of
epsilon, after a time of order the inverse of square root of epsilon. The
assumptions, which are essentially minimal, are that there exists a resonant
point for h and that the corresponding averaged perturbation is non-constant.
The conclusions, although very weak when compared to usual instability
phenomena, are also essentially optimal within this setting.
Chinese: 在这篇笔记中，我们考虑了在任意自由度下，作用角坐标中可积哈密顿系统的一个epsilon微扰的动力学，并证明了以下“微观扩散”的结果：在关于h和f的通用假设下，存在一个系统的轨道，其作用变量的漂移至少为epsilon的平方根阶，在时间上至少为epsilon的平方根的倒数阶之后。这些假设本质上是最小的，即存在一个与h共振的点，并且相应的平均扰动不是常数。结论虽然与通常的不稳定性现象相比非常微弱，但在这个设定中也是本质上最优的。
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English: The effects of randomly pinning particles in a model glass-forming fluid are
studied, with a focus on the dynamically heterogeneous relaxation in the
presence of pinning. We show how four-point dynamical correlations can be
analysed in real space, allowing direct extraction of a length scale that
characterises dynamical heterogeneity. In the presence of pinning, the
relaxation time of the glassy system increases by up to two decades, but there
is almost no increase in either the four-point correlation length or the
strength of the four-point correlations. We discuss the implications of these
results for theories of the glass transition.
Chinese: 研究了在模型玻璃形成流体中随机固定粒子的影响，重点关注固定存在时的动态异质弛豫。我们展示了如何在实空间分析四点动力学关联，从而可以直接提取表征动态异质的长度尺度。在固定存在时，玻璃系统的弛豫时间增加了两个数量级，但四点关联长度或四点关联强度几乎没有增加。我们讨论了这些结果对玻璃转变理论的启示。
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English: Two fundamental problems in computational game theory are computing a Nash
equilibrium and learning to exploit opponents given observations of their play
(opponent exploitation). The latter is perhaps even more important than the
former: Nash equilibrium does not have a compelling theoretical justification
in game classes other than two-player zero-sum, and for all games one can
potentially do better by exploiting perceived weaknesses of the opponent than
by following a static equilibrium strategy throughout the match. The natural
setting for opponent exploitation is the Bayesian setting where we have a prior
model that is integrated with observations to create a posterior opponent model
that we respond to. The most natural, and a well-studied prior distribution is
the Dirichlet distribution. An exact polynomial-time algorithm is known for
best-responding to the posterior distribution for an opponent assuming a
Dirichlet prior with multinomial sampling in normal-form games; however, for
imperfect-information games the best known algorithm is based on approximating
an infinite integral without theoretical guarantees. We present the first exact
algorithm for a natural class of imperfect-information games. We demonstrate
that our algorithm runs quickly in practice and outperforms the best prior
approaches. We also present an algorithm for the uniform prior setting.
Chinese: 计算纳什均衡和在观察对手的玩法后学习如何利用对手（对手利用）是计算博弈论中的两个基本问题。后者可能比前者更为重要：除了两人零和博弈之外，纳什均衡在其他博弈类中并没有令人信服的理论依据，对于所有游戏，通过利用对手感知到的弱点，人们可能比在整个比赛中遵循静态均衡策略表现得更好。对手利用的自然环境是贝叶斯环境，其中我们有一个先验模型，该模型与观察结果相结合，创建一个后验对手模型，我们对其做出反应。最自然且被广泛研究的前验分布是狄利克雷分布。对于假设在标准形式博弈中具有多项式采样狄利克雷先验的后验分布的最佳反应，已知存在一个精确的多项式时间算法；然而，对于不完全信息博弈，已知的最优算法是基于近似一个无限积分而没有理论保证。我们提出了第一个针对自然类不完全信息博弈的精确算法。我们证明了我们的算法在实际运行中速度很快，并且优于最佳先验方法。我们还提出了一种针对均匀先验设置的算法。
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English: Charge transfer is a fundamental interface process that can be harnessed for
light detection, photovoltaics, and photosynthesis. Recently, charge transfer
was exploited in nanophotonics to alter plasmon polaritons by involving
additional non-polaritonic materials to activate the charge transfer. Yet,
direct charge transfer between polaritonic materials hasn't been demonstrated.
We report the direct charge transfer in pure polaritonic van der Waals (vdW)
heterostructures of $\alpha$-MoO$_3$/graphene. We extracted the Fermi energy of
0.6 eV for graphene by infrared nano-imaging of charge transfer hyperbolic
polaritons in the vdW heterostructure. This unusually high Fermi energy is
attributed to the charge transfer between graphene and $\alpha$-MoO$_3$.
Moreover, we have observed charge transfer hyperbolic polaritons in multiple
energy-momentum dispersion branches with a wavelength elongation of up to 150%.
With support from the DFT calculation, we find that the charge transfer between
graphene and $\alpha$-MoO$_3$, absent in mechanically assembled vdW
heterostructures, is attributed to the relatively pristine heterointerface
preserved in the epitaxially grown vdW heterostructure. The direct charge
transfer and charge transfer hyperbolic polaritons demonstrated in our work
hold great promise for developing nano-optical circuits, computational devices,
communication systems, and light and energy manipulation devices.
Chinese: 电荷转移是一种基本的界面过程，可以用于光检测、光伏和光合作用。最近，在纳米光子学中，通过引入额外的非极化子材料来激活电荷转移，从而利用电荷转移来改变等离子体激元。然而，极化子材料之间的直接电荷转移尚未得到证明。我们报告了在纯极化子范德华（vdW）异质结构（$\alpha$-MoO$_3$/石墨烯）中的直接电荷转移。通过在vdW异质结构中对电荷转移双曲极化子进行红外纳米成像，我们提取了石墨烯的费米能级为0.6 eV。这种异常高的费米能级归因于石墨烯和$\alpha$-MoO$_3$之间的电荷转移。此外，我们还观察到在多个能量-动量色散分支中存在电荷转移双曲极化子，其波长延伸可达150%。在DFT计算的支持下，我们发现石墨烯和$\alpha$-MoO$_3$之间的电荷转移，这在机械组装的vdW异质结构中不存在，归因于外延生长的vdW异质结构中保留的相对纯净的异质界面。我们工作中展示的直接电荷转移和电荷转移双曲极化子，对于开发纳米光学电路、计算设备、通信系统和光能操控设备具有巨大的潜力。
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English: Electromechanical switching devices such as relays, solenoid valves, and
contactors offer several technical and economic advantages that make them
widely used in industry. However, uncontrolled operations result in undesirable
impact-related phenomena at the end of the stroke. As a solution, different
soft-landing controls have been proposed. Among them, feedforward control with
iterative techniques that adapt its parameters is a solution when real-time
feedback is not available. However, these techniques typically require a large
number of operations to converge or are computationally intensive, which limits
a real implementation. In this paper, we present a new algorithm for the
iterative adaptation that is able to eventually adapt the search coordinate
system and to reduce the search dimensional size in order to accelerate
convergence. Moreover, it automatically toggles between a derivative-free and a
gradient-based method to balance exploration and exploitation. To demonstrate
the high potential of the proposal, each novel part of the algorithm is
compared with a state-of-the-art approach via simulation.
Chinese: 电气机械开关设备，如继电器、电磁阀和接触器，在工业中得到了广泛应用，这得益于它们在技术和经济方面的多项优势。然而，不控制的操作会在行程结束时产生不希望的相关现象。作为解决方案，已经提出了不同的软着陆控制方法。其中，当没有实时反馈时，采用具有迭代技术的前馈控制是一种解决方案。然而，这些技术通常需要大量的操作才能收敛，或者计算密集，这限制了实际的应用。在本文中，我们提出了一种新的迭代适应算法，该算法能够最终适应搜索坐标系，并减少搜索维度大小以加速收敛。此外，它能够在无导数方法和基于梯度的方法之间自动切换，以平衡探索和利用。为了展示所提方案的高潜力，算法的每个新颖部分都通过仿真与最先进的方法进行了比较。
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English: We present Hinted Networks: a collection of architectural transformations for
improving the accuracies of neural network models for regression tasks, through
the injection of a prior for the output prediction (i.e. a hint). We ground our
investigations within the camera relocalization domain, and propose two
variants, namely the Hinted Embedding and Hinted Residual networks, both
applied to the PoseNet base model for regressing camera pose from an image. Our
evaluations show practical improvements in localization accuracy for standard
outdoor and indoor localization datasets, without using additional information.
We further assess the range of accuracy gains within an aerial-view
localization setup, simulated across vast areas at different times of the year.
Chinese: 我们提出了提示网络：一组用于通过注入输出预测先验（即提示）来提高回归任务中神经网络模型准确率的架构变换。我们将我们的研究建立在相机重定位领域内，并提出了两种变体，即提示嵌入和提示残差网络，两者都应用于PoseNet基础模型，用于从图像中回归相机姿态。我们的评估表明，对于标准室外和室内定位数据集，在未使用额外信息的情况下，定位精度有了实际上的提高。我们进一步评估了在空中视角定位设置中准确率提升的范围，该设置在一年中的不同时间模拟了广阔地区的场景。
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English: We study impartial take away games on 2 unordered piles of finite nonnegative
numbers of tokens $(x,y)$. Two players alternate in removing at least one and
at most all tokens from the respective piles, according to certain rules, and
the game terminates when a player in turn is unable to move. We follow the
normal play convention, which means that a player who cannot move loses. In the
game of Wythoff Nim, a player is allowed to remove either any number of tokens
from precisely one of the piles or the same number of tokens from both. Let
$\phi = \frac{1+\sqrt{5}}{2}$ and for all nonnegative integers $n$,
$A_n=\lfloor\phi n \rfloor$ and $B_n=A_n+n$. The P-positions of Wythoff Nim are
all pairs of piles with $A_n$ and $B_n$ tokens respectively. We study a
generalization of this game called $(1,2)\G$ where, in addition to the rules of
Wythoff Nim, a player has the choice to remove a positive number of tokens from
one of the piles and twice that number from the other pile. We show that there
is an infinite sector $\alpha \le y/x \le \alpha +\epsilon$, for given real
numbers $\alpha>1$ and $\epsilon > 0$, for which each $(x,y)$ is an N-position,
but that there are infinitely many P-positions for both $1\le y/x <\alpha $ and
$\alpha +\epsilon < y/x $. This proves a conjecture from a recent paper.
Namely, the adjoined set of moves in $(1,2)\G$ \emph{splits} the beam of slope
$\phi $ P-positions of Wythoff Nim. We also provide a lower bound on the lower
asymtotic density of lower pile heights of P-positions for extensions of
Wythoff Nim. Suppose that $(a_i)$ and $(b_i)$, $i>0$, is a pair of so-called
complementary sequences on the natural numbers which satisfy $(a_i)$ is
increasing and for all $i$, $a_i<b_i$, for all $i\ne j$, $b_i-a_i\ne b_j-a_j$.
Then $\liminf_{n\rightarrow \infty}\frac{#\{i\mid a_i < n\}}{n} \ge \phi^{-1}$.
Chinese: 我们研究了在两个无序的有限非负令牌堆$(x,y)$上的无偏拿走游戏。两个玩家轮流从各自的堆中至少拿走一个且最多拿走所有令牌，根据某些规则，当玩家无法移动时游戏结束。我们遵循正常玩法的惯例，即无法移动的玩家输。在Wythoff Nim游戏中，玩家可以选择从其中一个堆中拿走任意数量的令牌，或者从两个堆中同时拿走相同数量的令牌。令$\phi = \frac{1+\sqrt{5}}{2}$，对于所有非负整数$n$，$A_n=\lfloor\phi n \rfloor$和$B_n=A_n+n$。Wythoff Nim的P位置是所有具有$A_n$和$B_n$令牌的堆对。我们研究了Wythoff Nim的这一扩展游戏$(1,2)\G$，其中除了Wythoff Nim的规则外，玩家还可以选择从其中一个堆中拿走正数令牌，同时从另一个堆中拿走两倍的数量。我们证明了存在一个无限扇形$\alpha \le y/x \le \alpha +\epsilon$，对于给定的实数$\alpha>1$和$\epsilon > 0$，对于所有$(x,y)$都是N位置，但对于$1\le y/x <\alpha $和$\alpha +\epsilon < y/x $都存在无限多个P位置。这证明了最近一篇论文中的一个猜想。具体来说，$(1,2)\G$的相邻移动集合在$\phi$的P位置束上“分割”了Wythoff Nim。我们还为Wythoff Nim扩展游戏的P位置堆高度的下限密度提供了下界。假设$(a_i)$和$(b_i)$，$i>0$，是一对所谓的互补序列，它们在自然数上满足$(a_i)$递增，对于所有$i$，$a_i<b_i$，对于所有$i\ne j$，$b_i-a_i\ne b_j-a_j$。则$\liminf_{n\rightarrow \infty}\frac{#\{i\mid a_i < n\}}{n} \ge \phi^{-1}$。
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English: Mainframe systems are facing a critical shortage of developer workforce as
the current generation of COBOL developers retires. Furthermore, due to the
limited availability of public COBOL resources, entry-level developers, who
assume the mantle of legacy COBOL systems maintainers, face significant
difficulties during routine maintenance tasks, such as code comprehension and
defect location. While we made substantial advances in the field of software
maintenance for modern programming languages yearly, mainframe maintenance has
received limited attention. With this study, we aim to direct the attention of
researchers and practitioners towards investigating and addressing challenges
associated with mainframe development. Specifically, we explore the scope of
defects affecting COBOL systems and defect location strategies commonly
followed by COBOL developers and compare them with the modern programming
language counterparts. To this end, we surveyed 30 COBOL and 74 modern
Programming Language (PL) developers to understand the differences in defects
and defect location strategies employed by the two groups. Our preliminary
results show that: (1) major defect categories affecting the COBOL ecosystem
are different than defects encountered in modern PL software projects; (2) the
most challenging defect types in COBOL are also the ones that occur most
frequently; and (3) COBOL and modern PL developers follow similar strategies to
locate defective code.
Chinese: 大型机系统正面临开发人员短缺的重大危机，因为当前一代的COBOL开发者即将退休。此外，由于公共COBOL资源的有限可用性，那些承担维护遗留COBOL系统任务的新手开发者在执行例行维护任务时，如代码理解和缺陷定位，面临重大困难。虽然我们在现代编程语言的维护领域每年都取得了重大进展，但大型机维护却受到了有限的关注。通过这项研究，我们旨在引导研究人员和实践者去探索和解决与大型机开发相关联的挑战。具体来说，我们探讨了影响COBOL系统的缺陷范围以及COBOL开发者通常采用的缺陷定位策略，并将它们与现代编程语言的同类策略进行比较。为此，我们调查了30名COBOL和74名现代编程语言(PL)开发者，以了解这两个群体在缺陷和缺陷定位策略方面的差异。我们的初步结果表明：(1)影响COBOL生态系统的重大缺陷类别与现代PL软件项目中遇到的缺陷不同；(2)在COBOL中最具挑战性的缺陷类型也是出现频率最高的；(3)COBOL和现代PL开发者在定位有缺陷代码时采用相似的策略。
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English: During broadcast events such as the Superbowl, the U.S. Presidential and
Primary debates, etc., Twitter has become the de facto platform for crowds to
share perspectives and commentaries about them. Given an event and an
associated large-scale collection of tweets, there are two fundamental research
problems that have been receiving increasing attention in recent years. One is
to extract the topics covered by the event and the tweets; the other is to
segment the event. So far these problems have been viewed separately and
studied in isolation. In this work, we argue that these problems are in fact
inter-dependent and should be addressed together. We develop a joint Bayesian
model that performs topic modeling and event segmentation in one unified
framework. We evaluate the proposed model both quantitatively and qualitatively
on two large-scale tweet datasets associated with two events from different
domains to show that it improves significantly over baseline models.
Chinese: 在诸如超级碗、美国总统大选辩论和初选辩论等直播活动中，Twitter已经成为大众分享对这些活动观点和评论的事实上平台。给定一个事件及其相关的大量推文集合，近年来有两个基本的研究问题受到了越来越多的关注。一是提取事件和推文所涉及的主题；二是分割事件。到目前为止，这些问题一直是分开看待并在孤立状态下进行研究。在这项工作中，我们认为这些问题实际上是相互依赖的，应该一起解决。我们开发了一个联合贝叶斯模型，该模型在一个统一的框架中执行主题建模和事件分割。我们在两个不同领域的事件相关的大型推文数据集上对所提出的模型进行了定量和定性的评估，以表明它相对于基线模型有显著改进。
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English: Through the discussion of the fundamental properties of Lagrangian density
for a gravitational system, the theoretical foundations of the modified
Einstein field equations and the Lorentz and Levi-Civita conservation laws are
systematically studied. Our study confirms the view that they could be used as
the premises to establish a new cosmology.
Chinese: 通过讨论引力系统拉格朗日密度的基本性质，系统地研究了修改后的爱因斯坦场方程和洛伦兹-莱维-奇维塔守恒定律的理论基础。我们的研究证实了它们可以作为建立新宇宙学的先决条件这一观点。
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English: In animal behavioral biology, there are several cases in which an autonomous
observing/training system would be useful. 1) Observation of certain species
continuously, or for documenting specific events, which happen irregularly; 2)
Longterm intensive training of animals in preparation for behavioral
experiments; and 3) Training and testing of animals without human interference,
to eliminate potential cues and biases induced by humans. The primary goal of
this study is to build a system named CATOS (Computer Aided Training/Observing
System) that could be used in the above situations. As a proof of concept, the
system was built and tested in a pilot experiment, in which cats were trained
to press three buttons differently in response to three different sounds (human
speech) to receive food rewards. The system was built in use for about 6
months, successfully training two cats. One cat learned to press a particular
button, out of three buttons, to obtain the food reward with over 70 percent
correctness.
Chinese: 在动物行为生物学中，存在几种情况下一个自主的观察/训练系统会很有用。1) 对某些物种进行持续观察，或记录不定期发生的特定事件；2) 为行为实验而对动物进行长期密集训练；3) 在没有人类干扰的情况下对动物进行训练和测试，以消除人类可能引起的潜在线索和偏见。本研究的主要目标是构建一个名为CATOS（计算机辅助训练/观察系统）的系统，该系统可用于上述情况。作为一个概念验证，该系统在一个试点实验中进行了构建和测试，其中猫被训练对三种不同的声音（人类语言）做出不同的按键反应以获得食物奖励。该系统使用了大约6个月，成功训练了两只猫。其中一只猫学会了在三个按钮中选择一个特定的按钮，以超过70%的正确率获得食物奖励。
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English: Wall's finiteness obstruction is an algebraic K-theory invariant which
decides if a finitely dominated space is homotopy equivalent to a finite CW
complex. The object of this survey is to describe the invariant (which was
first formulated in 1965) and some of its many applications to the surgery
classification of manifolds.
Chinese: Wall的有限支配障碍是一个代数K理论不变量，它决定了有限支配空间是否与有限CW复形同伦等价。本综述的目标是描述这个不变量（它最初于1965年提出）及其在流形手术分类中的许多应用。
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English: We study the time evolution of the reduced Wigner function for a class of
quantum Brownian motion models. We derive two generalized uncertainty
relations. The first consists of a sharp lower bound on the uncertainty
function, $U = (\Delta p)^2 (\Delta q)^2 $, after evolution for time $t$ in the
presence of an environment. The second, a stronger and simpler result, consists
of a lower bound at time $t$ on a modified uncertainty function, essentially
the area enclosed by the $1-\sigma$ contour of the Wigner function. In both
cases the minimizing initial state is a non-minimal Gaussian pure state. These
generalized uncertainty relations supply a measure of the comparative size of
quantum and thermal fluctuations. We prove two simple inequalites, relating
uncertainty to von Neumann entropy, and the von Neumann entropy to linear
entropy. We also prove some results on the long-time limit of the Wigner
function for arbitrary initial states. For the harmonic oscillator the Wigner
function for all initial states becomes a Gaussian at large times (often, but
not always, a thermal state). We derive the explicit forms of the long-time
limit for the free particle (which does not in general go to a Gaussian), and
also for more general potentials in the approximation of high temperature.
Chinese: 我们研究了一类量子布朗运动模型的归一化Wigner函数的演化。我们推导了两个广义的不确定性关系。第一个关系包含在环境存在下，时间$t$后演化后不确定函数$U = (\Delta p)^2 (\Delta q)^2$的一个锐利下界。第二个，一个更强且更简洁的结果，包含在时间$t$时一个修改后的不确定函数的下界，这个函数基本上就是Wigner函数的$1-\sigma$等高线所围成的面积。在这两种情况下，最小化初始状态是一个非最小高斯纯态。这些广义的不确定性关系提供了一个衡量量子与热涨落相对大小的指标。我们证明了两个简单的不等式，将不确定性与冯·诺依曼熵关联起来，以及冯·诺依曼熵与线性熵关联起来。我们还证明了对于任意初始状态，Wigner函数长期极限的一些结果。对于谐振子，所有初始状态下的Wigner函数在长时间后变为高斯分布（通常但不是总是热态）。我们导出了自由粒子（这通常不会变为高斯分布）的长期极限的显式形式，以及在高温度近似下更一般势能的长期极限。
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English: We review quark model calculations of the transverse momentum dependent
parton distributions (TMDs). For the T-even TMDs, we discuss the physical
origin of model relations which hold in a large class of quark models. For the
T-odd TMDs we review results in a light-cone constituent quark model (CQM) with
the final state interaction effects generated via single-gluon exchange
mechanism. As phenomenological application, we show the good agreement between
results in the light-cone CQM and available experimental data for the Collins
asymmetry.
Chinese: 我们回顾了横动量依赖的夸克分布（TMDs）的夸克模型计算。对于T偶数TMDs，我们讨论了在大量夸克模型中保持的模型关系的物理起源。对于T奇数TMDs，我们回顾了在光锥组成夸克模型（CQM）中的结果，其中最终状态相互作用效应是通过单胶子交换机制产生的。作为现象学应用，我们展示了光锥CQM的结果与可用的实验数据在柯林斯不对称性方面的良好一致性。
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English: Quantum thermal states are known to be passive, as required by the second law
of thermodynamics. This paper studies the possible work extraction via coupling
the thermal bath to a qubit of either spin, fermion, or topological types,
which acts as a quantum thermal state at different temperatures. The amount of
work extraction is derived from the work statistics under a cyclic
nonequilibrium process. Though the work statistics of many-body systems are
known to be challenging to calculate explicitly, we propose an effective field
theory approach to tackle this problem by assuming the externally driven source
to couple to a specific quasiparticle operator of the thermal state. We show
that the work statistics can be expressed succinctly in terms of this
quasiparticle's thermal spectral function. We obtain the non-perturbative work
distribution function (WDF) for the pure thermal bath without the qubit
coupling. With qubit coupling, we get the second-order WDF, from which the
physical regime of work extraction can be pinned down precisely to help devise
quantum engines.
Chinese: 量子热态已知是被动的，这是由热力学第二定律所要求的。本文研究了通过将热浴耦合到自旋、费米子或拓扑类型的量子比特来提取工作的可能性，这些量子比特在不同的温度下作为量子热态。工作提取的数量是从循环非平衡过程中的工作统计中推导出来的。尽管多体系统的功统计明确计算起来具有挑战性，但我们提出了一种有效场论方法来解决这个问题，通过假设外部驱动源耦合到热态的特定准粒子算符。我们展示了这种准粒子的热谱函数可以简洁地表达工作统计。我们获得了纯热浴（不包括量子比特耦合）的非微扰工作分布函数（WDF）。通过量子比特耦合，我们得到了第二阶WDF，从而可以精确确定工作提取的物理范围，以帮助设计量子发动机。
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English: In this paper we demonstrate that the information encoded in \emph{one}
single (sufficiently large) $N$-body simulation can be used to reproduce
arbitrary numbers of halo catalogues, using approximated realisations of dark
matter density fields with different initial conditions. To this end we use as
a reference one realisation (from an ensemble of $300$) of the Minerva $N$-body
simulations and the recently published Bias Assignment Method to extract the
local and non-local bias linking the halo to the dark matter distribution. We
use an approximate (and fast) gravity solver to generate $300$ dark matter
density fields from the down-sampled initial conditions of the reference
simulation and sample each of these fields using the halo-bias and a kernel,
both calibrated from the arbitrarily chosen realisation of the reference
simulation. We show that the power spectrum, its variance and the three-point
statistics are reproduced within $\sim 2\%$ (up to $k\sim1.0\,h\,{\rm
Mpc}^{-1}$), $\sim 5-10\%$ and $\sim 10\%$, respectively. Using a model for the
real space power spectrum (with three free bias parameters), we show that the
covariance matrices obtained from our procedure lead to parameter uncertainties
that are compatible within $\sim 10\%$ with respect to those derived from the
reference covariance matrix, and motivate approaches that can help to reduce
these differences to $\sim 1\%$. Our method has the potential to learn from one
simulation with moderate volumes and high-mass resolution and extrapolate the
information of the bias and the kernel to larger volumes, making it ideal for
the construction of mock catalogues for present and forthcoming observational
campaigns such as Euclid or DESI.
Chinese: 在本文中，我们证明了包含在单个（足够大）N体模拟中编码的信息，可以利用具有不同初始条件的暗物质密度场近似实现来重现任意数量的星系团目录。为此，我们使用Minerva N体模拟的一个实现（来自300个实现中的一个）以及最近发表的偏差分配方法，提取将星系团与暗物质分布联系起来的局部和非局部偏差。我们使用一个近似（且快速）的引力求解器，从参考模拟的下采样初始条件生成300个暗物质密度场，并使用星系团偏差和一个核对这些场进行采样，这两个参数均从参考模拟中任意选择的实现进行校准。我们表明，功率谱、其方差和三点统计量分别在~2%（高达k~1.0 h Mpc^-1）、~5-10%和~10%的范围内得到重现。使用一个具有三个自由偏差参数的真空间功率谱模型，我们表明，我们程序得到的协方差矩阵导致参数不确定性，与从参考协方差矩阵导出的不确定性在~10%内兼容，并促使人们采取方法来将这些差异减少到~1%。我们的方法有潜力从中等体积和高质量分辨率的单个模拟中学习，并将偏差和核的信息外推到更大的体积，使其成为构建Euclid或DESI等当前和未来观测活动模拟目录的理想选择。
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English: Within the central parsec of the Galaxy, several tens of young stars orbiting
a central supermassive black hole are observed. A subset of these stars forms a
coherently rotating disc. Other observations reveal a massive molecular torus
which lies at a radius ~1.5pc from the centre. In this paper we consider the
gravitational influence of the molecular torus upon the stars of the stellar
disc. We derive an analytical formula for the rate of precession of individual
stellar orbits and we show that it is highly sensitive upon the orbital
semi-major axis and inclination with respect to the plane of the torus as well
as on the mass of the torus. Assuming that both the stellar disc and the
molecular torus are stable on the time-scale >6Myr, we constrain the mass of
the torus and its inclination with respect to the young stellar disc. We
further suggest that all young stars observed in the Galactic Centre may have a
common origin in a single coherently rotating structure with an opening angle
<5deg, which was partially destroyed (warped) during its lifetime by the
gravitational influence of the molecular torus.
Chinese: 在银河系中心 Parsec 范围内，观测到数十颗围绕中心超大质量黑洞运行的年轻恒星。其中一部分恒星形成了一个协同旋转的盘状结构。其他观测发现，一个质量巨大的分子环位于距离中心约 1.5pc 的半径处。本文研究分子环对恒星盘内恒星产生的引力影响。我们推导出单个恒星轨道进动速率的分析公式，并表明该速率对恒星轨道半长轴、相对于分子环平面的倾角以及分子环质量高度敏感。假设恒星盘和分子环在时间尺度大于 6Myr 的范围内保持稳定，我们约束了分子环的质量及其相对于年轻恒星盘的倾角。我们进一步提出，银河系中心观测到的所有年轻恒星可能源自一个开口角小于 5° 的单一协同旋转结构，该结构在其生命周期中因受分子环的引力影响而部分被破坏（扭曲）。
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English: Singularly perturbed systems (SPSs) are prevalent in engineering
applications, where numerically solving their initial value problems (IVPs) is
challenging due to stiffness arising from multiple time scales. Classical
explicit methods require impractically small time steps for stability, while
implicit methods developed for SPSs are computationally intensive and less
efficient for strongly nonlinear systems. This paper introduces a Stabilized
Multirate Explicit Scheme (SMES) that stabilizes classical explicit methods
without the need for small time steps or implicit formulations. By employing a
multirate approach with variable time steps, SMES allows the fast dynamics to
rapidly converge to their equilibrium manifold while slow dynamics evolve with
larger steps. Analysis shows that SMES achieves numerical stability with
significantly reduced computational effort and controlled error. Its
effectiveness is illustrated with a numerical example.
Chinese: 奇异扰动系统（SPSs）在工程应用中很常见，但由于多时间尺度引起的刚性问题，数值求解它们的初值问题（IVPs）具有挑战性。经典显式方法需要不切实际的小时间步长来保证稳定性，而为SPSs开发的隐式方法计算密集且对于强非线性系统效率较低。本文介绍了一种稳定多速率显式格式（SMES），它能够在无需小时间步长或隐式公式的条件下稳定经典显式方法。通过采用具有可变时间步长的多速率方法，SMES允许快速动力学快速收敛到它们的平衡流形，而慢速动力学则以较大的步长演化。分析表明，SMES在显著减少计算工作量和控制误差的同时实现了数值稳定性。一个数值算例说明了其有效性。
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English: Four anti-perovskite-type compounds, ZnNNi3, ZnCNi3, SnNCo3, and SnCCo3, are
synthesised through reactions between ingredient metal oxides and organic
compound melamine (C3H6N6). ZnNNi3 and ZnCNi3 are selectively synthesised by
choosing different reaction temperatures and nominal oxide-to-melamine ratios.
SnNCo3 is synthesised for the first time by this melamine method. Resistivity,
magnetisation, and heat capacity measurements reveal that SnNCo3 is a
correlated metal with a high density of states at the Fermi level. Our results
demonstrate that this feasible synthetic route using melamine is useful in the
search for complex metal carbides and nitrides toward novel functional
materials.
Chinese: 四种反钙钛矿型化合物ZnNNi3、ZnCNi3、SnNCo3和SnCCo3，通过原料金属氧化物与有机化合物三聚氰胺（C3H6N6）之间的反应合成。通过选择不同的反应温度和名义氧化物与三聚氰胺的摩尔比，可选择性合成ZnNNi3和ZnCNi3。首次通过该方法合成了SnNCo3。电阻率、磁化率和热容测量表明，SnNCo3是一种关联金属，在费米能级处具有高态密度。我们的结果表明，使用三聚氰胺的合成路线可行，有助于在复杂金属碳化物和氮化物中寻找新型功能材料。
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English: Classical entanglement refers to non-separable correlations between the
polarization direction and the polarization amplitude of a light field. The
degree of entanglement is quantified by the Schmidt number, taking the value of
unity for a separable state and two for a maximally entangled state. We propose
two detection methods to determine this number based on the distinguishable
patterns of interference between four light sources derived from the unknown
laser beam to be detected. The second method being a modification of the first
one has the interference fringes form discernable angles uniquely related to
the entangled state. The maximally entangled state corresponds to fringes
symmetric about the diagonal axis at either 45{\deg} or 135{\deg} direction
while the separable state corresponds to fringes symmetric either about the X-
or Y-axis or both simultaneously. States with Schmidt number between unity and
two have fringes of symmetric angles between these two extremes. The detection
methods would be beneficial to constructing transmission channels of
information contained in the classically entangled states.
Chinese: 经典纠缠指的是光场偏振方向和偏振振幅之间的非分离相关性。纠缠程度由施密特数量化，对于可分离态取值为1，对于最大纠缠态取值为2。我们提出了两种检测方法来确定这个数，这两种方法基于从待检测的未知激光束中获得的四个光源的明显干涉模式。第二种方法是对第一种方法的改进，其干涉条纹形成可辨别的角度，这些角度唯一地与纠缠态相关。最大纠缠态对应于对角线轴在45°或135°方向上对称的条纹，而可分离态对应于关于X轴或Y轴或同时关于这两轴对称的条纹。施密特数在1和2之间的状态具有介于这两种极端之间的对称角度的条纹。这些检测方法对于构建经典纠缠态中包含的信息传输通道将是有益的。
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English: The detailed magnetic field structure of the starless dense core CB81 (L1774,
Pipe 42) in the Pipe Nebula was determined based on near-infrared polarimetric
observations of background stars to measure dichroically polarized light
produced by magnetically aligned dust grains in the core. The magnetic fields
pervading CB81 were mapped using 147 stars and axisymmetrically distorted
hourglass-like fields were identified. On the basis of simple 2D and 3D
magnetic field modeling, the magnetic inclination angles in the plane-of-sky
and line-of-sight directions were determined to be $4^{\circ} \pm 8^{\circ}$
and $20^{\circ} \pm 20^{\circ}$, respectively. The total magnetic field
strength of CB81 was found to be $7.2 \pm 2.3$ $\mu{\rm G}$. Taking into
account the effects of thermal/turbulent pressure and magnetic fields, the
critical mass of CB81 was calculated to be $M_{\rm cr}=4.03 \pm 0.40$
M$_{\odot}$, which is close to the observed core mass of $M_{\rm core}=3.37 \pm
0.51$ M$_{\odot}$. We thus conclude that CB81 is in a condition close to the
critical state. In addition, a spatial offset of $92''$ was found between the
center of magnetic field geometry and the dust extinction distribution; this
offset structure could not have been produced by self-gravity. The data also
indicate a linear relationship between polarization and extinction up to $A_V
\sim 30$ mag going toward the core center. This result confirms that
near-infrared polarization can accurately trace the overall magnetic field
structure of the core.
Chinese: 基于对背景星近红外偏振观测，确定了管状星云中无星致密核心CB81（L1774，Pipe 42）的详细磁场结构。通过测量核心中磁取向尘埃颗粒产生的二向色偏振光，确定了核心中的磁场。使用147颗星绘制了贯穿CB81的磁场图，并识别出轴对称扭曲的沙漏形磁场。基于简单的二维和三维磁场建模，确定了平面和视线方向上的磁场倾角分别为$4^{\circ} \pm 8^{\circ}$和$20^{\circ} \pm 20^{\circ}$。CB81的总磁场强度为$7.2 \pm 2.3$ $\mu{\rm G}$。考虑到热/湍流压力和磁场的影响，计算得出CB81的临界质量为$M_{\rm cr}=4.03 \pm 0.40$ M$_{\odot}$，这接近观测到的核心质量$M_{\rm core}=3.37 \pm 0.51$ M$_{\odot}$。因此，我们得出结论，CB81处于接近临界状态。此外，在磁场几何中心与尘埃消光分布之间发现了$92''$的空间偏移；这种偏移结构不可能由自引力产生。数据还表明，从核心中心方向来看，偏振与消光之间存在线性关系，直到$A_V \sim 30$ mag。这一结果证实了近红外偏振可以准确追踪核心的整体磁场结构。
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English: In recent years, chaotic attractors have been extensively used in the design
of secure communication systems. One of the preferred ways of transmitting the
information signal is binary chaotic modulation, in which a binary message
modulates a parameter of the chaotic generator. This paper presents a method of
attack based on estimating the short-time period of the ciphertext generated
from the modulated chaotic attractor. By calculating and then filtering the
short-time period of the transmitted signal it is possible to obtain the binary
information signal with great accuracy without any knowledge of the parameters
of the underlying chaotic system. This method is successfully applied to
various secure communication systems proposed in the literature based on
different chaotic attractors.
Chinese: 近年来，混沌吸引子在安全通信系统的设计中得到了广泛的应用。传输信息信号的一种优选方式是二进制混沌调制，其中二进制信息调制混沌发生器的一个参数。本文提出了一种基于估计从调制混沌吸引器生成的密文短时周期的方法。通过计算并过滤传输信号的短时周期，可以在没有任何关于底层混沌系统参数知识的情况下，以极高的精度获得二进制信息信号。这种方法成功地应用于文献中提出的基于不同混沌吸引器的各种安全通信系统。
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English: In multiple attribute decision analysis (MADA) problems, one often needs to
deal with assessment information with uncertainty. The evidential reasoning
approach is one of the most effective methods to deal with such MADA problems.
As kernel of the evidential reasoning approach, an original evidential
reasoning (ER) algorithm was firstly proposed by Yang et al, and later they
modified the ER algorithm in order to satisfy the proposed four synthesis
axioms with which a rational aggregation process needs to satisfy. However, up
to present, the essential difference of the two ER algorithms as well as the
rationality of the synthesis axioms are still unclear. In this paper, we
analyze the ER algorithms in Dempster-Shafer theory (DST) framework and prove
that the original ER algorithm follows the reliability discounting and
combination scheme, while the modified one follows the importance discounting
and combination scheme. Further we reveal that the four synthesis axioms are
not valid criteria to check the rationality of one attribute aggregation
algorithm. Based on these new findings, an extended ER algorithm is proposed to
take into account both the reliability and importance of different attributes,
which provides a more general attribute aggregation scheme for MADA with
uncertainty. A motorcycle performance assessment problem is examined to
illustrate the proposed algorithm.
Chinese: 在多属性决策分析（MADA）问题中，往往需要处理具有不确定性的评估信息。证据推理方法是处理此类MADA问题最有效的方法之一。作为证据推理方法的核心，阳等人首先提出了原始证据推理（ER）算法，并后来他们修改了ER算法，以满足提出的四个合成公理，这些公理是理性聚合过程需要满足的。然而，到目前为止，这两个ER算法的本质差异以及合成公理的合理性仍然不清楚。在本文中，我们分析了在Dempster-Shafer理论（DST）框架下的ER算法，并证明原始ER算法遵循可靠性折扣和组合方案，而修改后的算法遵循重要性折扣和组合方案。进一步揭示了四个合成公理不是检查属性聚合算法合理性的有效标准。基于这些新发现，提出了一种扩展的ER算法，考虑了不同属性的可靠性和重要性，为具有不确定性的MADA提供了一个更通用的属性聚合方案。通过摩托车性能评估问题的案例研究，阐述了所提出算法的应用。
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English: We have investigated the confinement of 3-D vortices in specific cases of
Type-II ($\kappa = 2$) nano-superconducting devices. The emergent pattern of
vortices greatly depends on the orientation of an applied magnetic field
(transverse or longitudinal), and the size of the devices (a few coherence
lengths $\xi$). Herein, cylindrical geometries are examined. The surface
barriers become very significant in these nano-systems, and hence the
characteristics of the vortices become highly sensitive to the shape of the
system and direction of an applied field. It is observed that nano-cylindrical
superconductors, depending on their sizes, can display either first or second
order phase transitions, under the influence of a longitudinal field. In the
confined geometries, nucleation of a giant vortex state composed of a n-quanta
emerges for the longitudinal magnetic field.
Chinese: 我们对II型（$\kappa = 2$）纳米超导器件中三维涡旋的约束进行了研究。涡旋的涌现模式很大程度上取决于外加磁场的方向（横向或纵向）以及器件的尺寸（几个相干长度$\xi$）。本文研究了圆柱形几何结构。在这些纳米系统中，表面势垒变得非常重要，因此涡旋的特性对系统的形状和施加场的方向高度敏感。研究发现，纳米圆柱形超导体在纵向磁场作用下，根据其尺寸可能表现出一级或二级相变。在约束几何结构中，纵向磁场下会出现由n量子组成的巨涡旋态的成核。
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English: Online class-incremental continual learning (CL) studies the problem of
learning new classes continually from an online non-stationary data stream,
intending to adapt to new data while mitigating catastrophic forgetting. While
memory replay has shown promising results, the recency bias in online learning
caused by the commonly used Softmax classifier remains an unsolved challenge.
Although the Nearest-Class-Mean (NCM) classifier is significantly undervalued
in the CL community, we demonstrate that it is a simple yet effective
substitute for the Softmax classifier. It addresses the recency bias and avoids
structural changes in the fully-connected layer for new classes. Moreover, we
observe considerable and consistent performance gains when replacing the
Softmax classifier with the NCM classifier for several state-of-the-art replay
methods. To leverage the NCM classifier more effectively, data embeddings
belonging to the same class should be clustered and well-separated from those
with a different class label. To this end, we contribute Supervised Contrastive
Replay (SCR), which explicitly encourages samples from the same class to
cluster tightly in embedding space while pushing those of different classes
further apart during replay-based training. Overall, we observe that our
proposed SCR substantially reduces catastrophic forgetting and outperforms
state-of-the-art CL methods by a significant margin on a variety of datasets.
Chinese: 在线课程增量持续学习（CL）研究从在线非平稳数据流中持续学习新类别的问题，旨在适应新数据同时减轻灾难性遗忘。虽然记忆重放已经显示出有希望的结果，但由常用Softmax分类器引起的在线学习中的近期偏差仍然是一个未解决的问题。尽管Nearest-Class-Mean（NCM）分类器在CL社区中被严重低估，但我们证明它是一个简单而有效的Softmax分类器的替代品。它解决了近期偏差问题，并避免了新类别在全连接层中的结构变化。此外，我们发现当用NCM分类器替换Softmax分类器进行几种最先进的重放方法时，观察到相当一致的性能提升。为了更有效地利用NCM分类器，属于同一类的数据嵌入应该被聚类，并且与不同类别标签的数据嵌入保持良好的分离。为此，我们贡献了监督对比重放（SCR），该算法在基于重放的训练过程中明确鼓励来自同一类的样本在嵌入空间中紧密聚类，同时将不同类别的样本推得更远。总的来说，我们观察到我们提出的SCR显著减少了灾难性遗忘，并在各种数据集上以显著的优势超越了最先进的CL方法。
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English: We define a stronger property than unique ergodicity with respect to the
fixed-point subalgebra previously investigated by Abadie and Dykema. Such a
property is denoted as F-strict weak mixing (F stands for the Markov projection
onto the fixed-point operator system). Then we show that the free shifts on the
reduced C*-algebras of RD-groups, including the free group on infinitely many
generators, and amalgamated free product C*-algebras, considered by Abadie and
Dykema, are all strictly weak mixing and not merely uniquely ergodic.
Chinese: 我们定义了一个比唯一遍历性更强的性质，该性质针对Abadie和Dykema先前研究过的固定点子代数。这种性质记作F-严格弱混合性（F代表映射到不动点算子系统的马尔可夫投影）。然后我们证明，Abadie和Dykema所考虑的RD群的约化C*-代数上的自由移位，包括无限多个生成元的自由群，以及自由积C*-代数，都是严格弱混合的，而不仅仅是唯一遍历的。
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English: Binary field extensions are fundamental to many applications, such as
multivariate public key cryptography, code-based cryptography, and
error-correcting codes. Their implementation requires a foundation in number
theory and algebraic geometry and necessitates the utilization of efficient
bases. The continuous increase in the power of computation, and the design of
new (quantum) computers increase the threat to the security of systems and
impose increasingly demanding encryption standards with huge polynomial or
extension degrees. For cryptographic purposes or other common implementations
of finite fields arithmetic, it is essential to explore a wide range of
implementations with diverse bases. Unlike some bases, polynomial and Gaussian
normal bases are well-documented and widely employed. In this paper, we explore
other forms of bases of $\mathbb{F}_{2^n}$ over $\mathbb{F}_2$ to demonstrate
efficient implementation of operations within different ranges. To achieve
this, we leverage results on fast computations and elliptic periods introduced
by Couveignes and Lercier, and subsequently expanded upon by Ezome and Sall.
This leads to the establishment of new tables for efficient computation over
binary fields.
Chinese: 二进制域扩展对于许多应用至关重要，例如多元公钥密码学、基于代码的密码学和纠错码。它们的实现需要数论和代数几何的基础知识，并需要使用高效的基。计算能力的持续提升和新（量子）计算机的设计增加了对系统安全的威胁，并提出了越来越严格的加密标准，这些标准具有巨大的多项式或扩展度。对于密码学目的或其他有限域算术的常见实现，探索具有不同基的广泛实现是至关重要的。与某些基不同，多项式和高斯正态基有良好的文献记载并被广泛使用。在这篇论文中，我们探讨了 $\mathbb{F}_{2^n}$ 在 $\mathbb{F}_2$ 上的其他基形式，以展示在不同范围内操作的效率实现。为了实现这一点，我们利用了 Couveignes 和 Lercier 提出的快速计算和椭圆周期的结果，以及 Ezome 和 Sall 的进一步扩展。这导致了新的二进制域上高效计算表的建立。
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English: We show that explicit pragmatic inference aids in correctly generating and
following natural language instructions for complex, sequential tasks. Our
pragmatics-enabled models reason about why speakers produce certain
instructions, and about how listeners will react upon hearing them. Like
previous pragmatic models, we use learned base listener and speaker models to
build a pragmatic speaker that uses the base listener to simulate the
interpretation of candidate descriptions, and a pragmatic listener that reasons
counterfactually about alternative descriptions. We extend these models to
tasks with sequential structure. Evaluation of language generation and
interpretation shows that pragmatic inference improves state-of-the-art
listener models (at correctly interpreting human instructions) and speaker
models (at producing instructions correctly interpreted by humans) in diverse
settings.
Chinese: 我们表明，显式的语用推理有助于正确生成和遵循复杂、顺序性任务的自然语言指令。我们的语用模型能够推理说话者为何产生某些指令，以及听者听到这些指令后会作何反应。类似于之前的语用模型，我们使用学习到的基线听者和说话者模型来构建一个语用说话者，该说话者使用基线听者来模拟候选描述的解释，以及一个语用听者，该听者对替代描述进行反事实推理。我们将这些模型扩展到具有顺序结构的任务。对语言生成和解释的评价表明，语用推理在多种设置中提高了最先进的听者模型（在正确解释人类指令方面）和说话者模型（在产生人类正确解释的指令方面）。
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English: Social impact evaluations are emerging as a useful tool to understand,
document, and evaluate the societal impacts of generative AI. In this
provocation, we begin to think carefully about the types of experts and
expertise that are needed to conduct robust social impact evaluations of
generative AI. We suggest that doing so will require thoughtfully eliciting and
integrating insights from a range of "domain experts" and "experiential
experts," and close with five open questions.
Chinese: 社会影响评估正逐渐成为理解、记录和评估生成式人工智能对社会影响的有用工具。在这篇挑衅性的文章中，我们开始仔细思考进行稳健的生成式人工智能社会影响评估所需的专家类型和专业知识。我们建议，这样做需要深思熟虑地征求和整合来自各种“领域专家”和“经验专家”的见解，并以五个开放性问题结束。
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English: With the advent of large language models (LLMs) and multimodal large language
models (MLLMs), the potential of retrieval-augmented generation (RAG) has
attracted considerable research attention. Various novel algorithms and models
have been introduced to enhance different aspects of RAG systems. However, the
absence of a standardized framework for implementation, coupled with the
inherently complex RAG process, makes it challenging and time-consuming for
researchers to compare and evaluate these approaches in a consistent
environment. Existing RAG toolkits, such as LangChain and LlamaIndex, while
available, are often heavy and inflexibly, failing to meet the customization
needs of researchers. In response to this challenge, we develop \ours{}, an
efficient and modular open-source toolkit designed to assist researchers in
reproducing and comparing existing RAG methods and developing their own
algorithms within a unified framework. Our toolkit has implemented 16 advanced
RAG methods and gathered and organized 38 benchmark datasets. It has various
features, including a customizable modular framework, multimodal RAG
capabilities, a rich collection of pre-implemented RAG works, comprehensive
datasets, efficient auxiliary pre-processing scripts, and extensive and
standard evaluation metrics. Our toolkit and resources are available at
https://github.com/RUC-NLPIR/FlashRAG.
Chinese: 随着大型语言模型（LLMs）和多模态大型语言模型（MLLMs）的出现，检索增强生成（RAG）的潜力吸引了大量的研究关注。已经引入了各种新颖的算法和模型来增强RAG系统的不同方面。然而，由于缺乏实施的标准框架，以及RAG过程本身的复杂性，研究人员在一致的环境中比较和评估这些方法变得具有挑战性和耗时。现有的RAG工具包，如LangChain和LlamaIndex，虽然可用，但通常重量级且缺乏灵活性，无法满足研究人员定制化的需求。为了应对这一挑战，我们开发了\ours{}，这是一个高效且模块化的开源工具包，旨在帮助研究人员在统一框架内重现和比较现有的RAG方法，并开发他们自己的算法。我们的工具包实现了16种先进的RAG方法，并收集和整理了38个基准数据集。它具有各种功能，包括可定制的模块化框架、多模态RAG能力、丰富的预实现RAG作品集合、全面的数据库、高效的辅助预处理脚本以及广泛的标准化评估指标。我们的工具包和资源可在https://github.com/RUC-NLPIR/FlashRAG上获取。
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English: The problem of testing low-degree polynomials has received significant
attention over the years due to its importance in theoretical computer science,
and in particular in complexity theory. The problem is specified by three
parameters: field size $q$, degree $d$ and proximity parameter $\delta$, and
the goal is to design a tester making as few as possible queries to a given
function, which is able to distinguish between the case the given function has
degree at most $d$, and the case the given function is $\delta$-far from any
degree $d$ function.
A tester is called optimal if it makes $O(q^d+1/\delta)$ queries (which are
known to be necessary). For the field of size $q$, the natural $t$-flat tester
was shown to be optimal first by Bhattacharyya et al. for $q=2$, and later by
Haramaty et al. for all prime powers $q$. The dependency on the field size,
however, is a tower-type function.
We improve the results above, showing that the dependency on the field size
is polynomial. Our approach also applies in the more general setting of lifted
affine invariant codes, and is based on studying the structure of the
collection of erroneous subspaces. i.e. subspaces $A$ such that $f|_{A}$ has
degree greater than $d$. Towards this end, we observe that these sets are
poorly expanding in the affine version of the Grassmann graph and use that to
establish structural results on them via global hypercontractivity. We then use
this structure to perform local correction on $f$.
Chinese: 多年来，由于在理论计算机科学，尤其是在复杂性理论中的重要性，测试低次多项式的问题受到了广泛关注。该问题由三个参数指定：字段大小 $q$、次数 $d$ 和邻近参数 $\delta$，目标是设计一个测试器，使其对给定函数的查询尽可能少，能够区分给定函数的次数最多为 $d$ 的情况，以及给定函数与任何次数为 $d$ 的函数相距 $\delta$ 的情况。
如果一个测试器进行 $O(q^d+1/\delta)$ 次查询（已知这是必要的），则称为最优的。对于大小为 $q$ 的字段，Bhattacharyya 等人首先证明了 $q=2$ 时自然 $t$-平坦测试器的最优性，后来 Haramaty 等人证明了所有素数幂 $q$ 的情况。然而，对字段大小的依赖是一个塔形函数。
我们改进了上述结果，表明对字段大小的依赖是多项式的。我们的方法也适用于更一般的提升仿射不变码的设置，并基于研究错误子空间集合的结构。即子空间 $A$，使得 $f|_{A}$ 的次数大于 $d$。为此，我们观察到这些集合在 Grassmann 图的仿射版本中扩展性较差，并利用这一点通过全局超合同性来建立它们的结构结果。然后我们利用这种结构对 $f$ 进行局部纠错。
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English: We study the transferring of useful energy (work) along a transmission line
that allows for partial preservation of quantum coherence. As a figure of merit
we adopt the maximum values that ergotropy, total ergotropy, and
non-equilibrium free-energy attain at the output of the line for an assigned
input energy threshold. For Phase-Invariant Bosonic Gaussian Channels (BGCs)
models, we show that coherent inputs are optimal. For (one-mode) not
Phase-Invariant BGCs we solve the optimization problem under the extra
restriction of Gaussian input signals.
Chinese: 我们研究在允许部分保持量子相干性的传输线中，有用能量（功）的转移。作为品质因数，我们采用在指定输入能量阈值下，线输出端所达到的熵力、总熵力和非平衡自由能的最大值。对于相位不变玻色高斯信道（BGCs）模型，我们证明相干输入是最优的。对于（单模）非相位不变BGCs，我们在高斯输入信号额外限制下解决了优化问题。
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English: We consider one infinite path of a Random Walk in Random Environment (RWRE,
for short) in an unknown environment. This environment consists of either
i.i.d.\ site or bond randomness. At each position the random walker stops and
tells us the environment it sees at the point where it is, without telling us,
where it is. These observations $\chi'$ are spoiled by reading errors that
occur with probability $p<1$. We show: If the RWRE is recurrent and satisfies
the standard assumptions on such RWREs, then with probability one in the
environment, the errors, and the random walk we are able reconstruct the law of
the environment. For most situations this result is even independent of the
value of $p$. If the distribution of the environment has a non-atomic part, we
can even reconstruct the environment itself, up to translation.
Chinese: 我们考虑一个在未知环境中随机游走（RWRE，简称）的无限路径。这个环境由独立同分布的站点或键随机性组成。在每个位置，随机游走者停下并告诉我们它所在位置的环境，但不告诉我们它具体在哪里。这些观察值 $\chi'$ 由于概率 $p<1$ 发生的读数错误而受到破坏。我们证明：如果RWRE是回归的并且满足此类RWRE的标准假设，那么在环境和错误中，以概率一，我们能够重建环境的法律。对于大多数情况，这个结果甚至与 $p$ 的值无关。如果环境的分布有一个非原子的部分，我们甚至可以重建环境本身，直到平移。
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English: Tunneling spectra are reported for Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta} (Bi-2212)
over a wide doping range using superconductor-insulator-superconductor (SIS)
break junctions. The energy gap inferred from the tunneling data displays a
remarkable monotonic dependence on doping, increasing to very large values in
the underdoped region even as T_c decreases. This leads to unphysically large
values of the strong coupling ratio ($\sim$20). The tunneling spectra are
qualitatively similar over the entire doping range even though the gap
parameter, $\Delta$, changes from 12 meV to 60 meV. Each spectrum exhibits dip
and hump features at high bias with characteristic energies that scale with the
superconducting gap. Tunneling spectra of near optimally-doped
Tl_{2}Ba_{2}CuO_{6+\delta} (Tl-2201) also display a weak dip feature in
superconductor-insulator-normal metal (SIN) junctions. Generated SIS spectra of
Tl-2201 are compared with measured spectra on Bi-2212 and it is concluded that
the dip and hump features are generic to high temperature superconductors.
Chinese: 在超导体-绝缘体-超导体（SIS）断开结中，对Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta}（Bi-2212）在广泛的掺杂范围内进行了隧道光谱的报道。从隧道数据推断出的能隙显示出对掺杂的显著单调依赖性，即使在T_c降低的情况下，在欠掺杂区域也能增加到非常大的值。这导致强耦合比（$\sim$20）出现不物理的大值。在整个掺杂范围内，隧道光谱在定性上是相似的，尽管能隙参数$\Delta$从12 meV变化到60 meV。每个光谱在高偏压下都表现出凹陷和隆起特征，其特征能量与超导能隙成正比。近最佳掺杂的Tl_{2}Ba_{2}CuO_{6+\delta}（Tl-2201）的隧道光谱也在超导体-绝缘体-正常金属（SIN）结中显示出微弱的凹陷特征。Tl-2201生成的SIS光谱与Bi-2212上的测量光谱进行了比较，并得出结论，凹陷和隆起特征是高温超导体的普遍特征。
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English: In 4d lattice simulations of Standard Model like theories, the renormalized
gauge coupling in the broken phase can be determined from the prefactor of the
Yukawa term in the static potential. We compute the same quantity in terms of
the conventional MSbar scheme gauge coupling. The result allows for a further
non-perturbative test of finite temperature dimensional reduction, by a
comparison of the critical temperatures for the electroweak phase transition as
obtained with 4d lattice simulations and with 3d effective theory simulations.
Chinese: 在标准模型类理论的4d晶格模拟中，从静态势中的Yukawa项的预因子可以确定破缺相中的重整化规范耦合。我们用传统的MSbar方案规范耦合来计算相同的量。这个结果允许通过比较4d晶格模拟和3d有效理论模拟得到的电弱相变临界温度，进一步对有限温度下的维度缩减进行非微扰测试。
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English: Segmented silicon detectors (micropixel and microstrip) are the main type of
detectors used in the inner trackers of Large Hadron Collider (LHC) experiments
at CERN. Due to the high luminosity and eventual high fluence, detectors with
fast response to fit the short shaping time of 20 ns and sufficient radiation
hardness are required.
Measurements carried out at the Ioffe Institute have shown a reversal of the
pulse polarity in the detector response to short-range charge injection. Since
the measured negative signal is about 30-60% of the peak positive signal, the
effect strongly reduces the CCE even in non-irradiated detectors. For further
investigation of the phenomenon the measurements have been reproduced by TCAD
simulations.
As for the measurements, the simulation study was applied for the p-on-n
strip detectors similar in geometry to those developed for the ATLAS experiment
and for the Ioffe Institute designed p-on-n strip detectors with each strip
having a window in the metallization covering the p$^+$ implant, allowing the
generation of electron-hole pairs under the strip implant. Red laser scans
across the strips and the interstrip gap with varying laser diameters and
Si-SiO$_2$ interface charge densities were carried out. The results verify the
experimentally observed negative response along the scan in the interstrip gap.
When the laser spot is positioned on the strip p$^+$ implant the negative
response vanishes and the collected charge at the active strip proportionally
increases.
The simulation results offer a further insight and understanding of the
influence of the oxide charge density in the signal formation. The observed
effects and details of the detector response for different charge injection
positions are discussed in the context of Ramo's theorem.
Chinese: 分段的硅探测器（微像素和微条）是大型强子对撞机（LHC）实验中欧洲核子研究中心（CERN）内环轨道器使用的主要探测器类型。由于高亮度和高通量，需要具有快速响应的探测器以适应20纳秒的短形成时间，并且需要足够的抗辐射性。
伊奥夫研究所进行测量表明，探测器对短程电荷注入的响应出现了脉冲极性反转。由于测得的负信号约为峰值正信号的30-60%，这种效应即使在未辐照的探测器中也强烈降低了电荷收集效率（CCE）。为了进一步研究这种现象，测量结果已通过TCAD模拟进行重现。
就测量而言，模拟研究应用于与ATLAS实验开发的几何形状相似的p-on-n条形探测器，以及伊奥夫研究所设计的p-on-n条形探测器，每个条形在金属化覆盖p+注入的区域有一个窗口，允许在条形注入下方产生电子空穴对。进行了跨条形和条间间隙的红激光扫描，激光直径和Si-SiO₂界面电荷密度各不相同。结果验证了实验观察到的条间间隙扫描过程中的负响应。当激光光斑位于条形p+注入处时，负响应消失，收集在活性条上的电荷成比例增加。
模拟结果进一步提供了对氧化物电荷密度在信号形成中影响的深入了解和理解。在不同电荷注入位置观察到的效应和探测器响应的细节在拉莫定理的背景下进行了讨论。
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English: A complete set of diagnostic tools aimed at producing synthetic synchrotron
emissivity, polarization, and spectral index maps from relativistic MHD
simulations is presented. As a first application we consider here the case of
the emission from Pulsar Wind Nebulae (PWNe). The proposed method is based on
the addition, on top of the basic set of MHD equations, of an extra equation
describing the evolution of the maximum energy of the emitting particles. This
equation takes into account adiabatic and synchrotron losses along streamlines
for the distribution of emitting particles and its formulation is such that it
is easily implemented in any numerical scheme for relativistic MHD. Application
to the axisymmetric simulations of PWNe, analogous to those described by Del
Zanna et al. (2004, A&A, 421, 1063), allows direct comparison between the
numerical results and observations of the inner structure of the Crab Nebula,
and similar objects, in the optical and X-ray bands. We are able to match most
of the observed features typical of PWNe, like the equatorial torus and the
polar jets, with velocities in the correct range, as well as finer emission
details, like arcs, rings and the bright knot, that turn out to arise mainly
from Doppler boosting effects. Spectral properties appear to be well reproduced
too: detailed spectral index maps are produced for the first time and show
softening towards the PWN outer borders, whereas spectral breaks appear in
integrated spectra. The emission details are found to strongly depend on both
the average wind magnetization (here approximately 2%), and on the magnetic
field shape.
Chinese: 一套旨在从相对论性MHD模拟中产生合成同步辐射发射率、极化和光谱指数图的完整诊断工具被提出。作为首次应用，我们考虑了脉冲星风星云（PWNe）的发射情况。所提出的方法是在基本的MHD方程集之上，增加一个描述发射粒子最大能量演化的额外方程。这个方程考虑了发射粒子分布的流线上的绝热和同步辐射损失，并且其公式化使得它能够轻松地集成到任何相对论性MHD的数值方案中。将此方法应用于与Del Zanna等人（2004年，A&A，421，1063）所描述相似的PWNe轴对称模拟，允许在数值结果和蟹状星云等类似物体的内部结构的光学和X射线波段观测之间进行直接比较。我们能够将大多数典型的PWNe观测特征，如赤道环和极射流，与正确的速度范围匹配，以及更精细的发射细节，如弧、环和明亮的结，这些主要是由多普勒增强效应引起的。光谱特性似乎也得到了很好的再现：首次产生了详细的光谱指数图，并显示出向PWN外边缘的软化，而光谱断点则出现在积分光谱中。发现发射细节强烈依赖于平均风磁化（此处约为2%）和磁场形状。
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English: Response-adaptive designs allow the randomization probabilities to change
during the course of a trial based on cumulated response data, so that a
greater proportion of patients can be allocated to the better performing
treatments. A major concern over the use of response-adaptive designs in
practice, particularly from a regulatory viewpoint, is controlling the type I
error rate. In particular, we show that the naive z-test can have an inflated
type I error rate even after applying a Bonferroni correction. Simulation
studies have often been used to demonstrate error control, but do not provide a
guarantee. In this paper, we present adaptive testing procedures for normally
distributed outcomes that ensure strong familywise error control, by
iteratively applying the conditional invariance principle. Our approach can be
used for fully sequential and block randomized trials, and for a large class of
adaptive randomization rules found in the literature. We show there is a high
price to pay in terms of power to guarantee familywise error control for
randomization schemes with extreme allocation probabilities. However, for
proposed Bayesian adaptive randomization schemes in the literature, our
adaptive tests maintain or increase the power of the trial compared to the
z-test. We illustrate our method using a three-armed trial in primary
hypercholesterolemia.
Chinese: 响应适应性设计允许在试验过程中根据累积的响应数据改变随机化概率，从而使更大比例的患者被分配到表现更好的治疗方案。在实践中使用响应适应性设计的主要担忧，尤其是从监管角度来看，是控制I类错误率。特别是，我们表明，即使应用了Bonferroni校正，朴素z检验也可能具有膨胀的I类错误率。模拟研究经常被用来证明错误控制，但并不提供保证。在本文中，我们提出了适用于正态分布结果的适应性测试程序，通过迭代应用条件不变性原理，确保强烈的家族错误控制。我们的方法可用于完全顺序和块随机化试验，以及文献中发现的广泛适应性随机化规则。我们表明，为了保证具有极端分配概率的随机化方案的家族错误控制，需要付出高昂的代价。然而，对于文献中提出的贝叶斯适应性随机化方案，我们的适应性测试与z检验相比，保持了或增加了试验的效力。我们使用一个三臂试验在原发性高胆固醇血症中说明了我们的方法。
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English: With high luminosity and energy at the ILC and clean SM backgrounds, the
top-charm production at the ILC should have powerful potential to probe new
physics. The littlest Higgs model with discrete symmetry named "T-parity"(LHT)
is one of the most promising new physics models. In this paper, we study the FC
processes $e^+e^-(\gamma\gamma)\to t\bar{c}$ at the ILC in the LHT model. Our
study shows that the LHT model can make a significant contribution to these
processes. When the masses of mirror quarks become large, these two processes
are accessible at the ILC. So the top-charm production at the ILC provides a
unique way to study the properties of the FC couplings in the LHT model and
furthermore test the model.
Chinese: 在ILC（国际直线对撞机）的高亮度和高能量以及干净的SM（标准模型）背景条件下，ILC上的顶夸克 charm 产生过程应该具有强大的潜力来探测新物理。被称为“T宇称”（LHT）的最小希格斯模型是众多新物理模型中最有希望的之一。在本文中，我们研究了LHT模型中ILC上的$e^+e^-(\gamma\gamma)\to t\bar{c}$过程。我们的研究表明，LHT模型可以对这些过程做出显著的贡献。当镜像夸克的质量变得很大时，这两个过程在ILC上都是可实现的。因此，ILC上的顶 charm 产生过程为研究LHT模型中FC耦合的性质提供了一种独特的方法，并且可以进一步验证该模型。
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English: We propose a linear-optical implementation of a hyperentanglement-assisted
quantum error-correcting code. The code is hyperentanglement-assisted because
the shared entanglement resource is a photonic state hyperentangled in
polarization and orbital angular momentum. It is possible to encode, decode,
and diagnose channel errors using linear-optical techniques. The code corrects
for polarization "flip" errors and is thus suitable only for a
proof-of-principle experiment. The encoding and decoding circuits use a
Knill-Laflamme-Milburn-like scheme for transforming polarization and orbital
angular momentum photonic qubits. A numerical optimization algorithm finds a
unit-fidelity encoding circuit that requires only three ancilla modes and has
success probability equal to 0.0097.
Chinese: 我们提出了一种超纠缠辅助量子纠错码的线性光学实现。该码是超纠缠辅助的，因为共享的纠缠资源是一种在偏振和轨道角动量上超纠缠的光子态。可以使用线性光学技术进行编码、解码和诊断信道错误。该码可以纠正偏振“翻转”错误，因此仅适用于原理验证实验。编码和解码电路使用类似于Knill-Laflamme-Milburn的方案来转换偏振和轨道角动量光子量子比特。一种数值优化算法找到了一个单位保真度编码电路，该电路只需要三个辅助模式，并且成功概率等于0.0097。
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English: The effects of Co2+ doping on the structural, magnetic and dielectric
properties of the multiferroic frustrated antiferromagnet Mn3TeO6 have been
investigated. Ceramic samples of the solid solution series Mn3-xCoxTeO6 were
prepared by a solid-state reaction route. X-ray and neutron powder diffraction
and electron microscopy techniques were combined with calorimetric, dielectric
and magnetic measurements to investigate the dependence of the crystal
structure and physical properties on temperature and composition. It is shown
that the compounds with x up to 2.4 all adopt the trigonal corundum-related
structure of pure Mn3TeO6 (space group R-3) in the temperature range 5-295 K
and that the lattice parameters a and c and the unit-cell volume V decrease
linearly with increasing Co2+ concentration. The low- temperature magnetic
susceptibility and heat capacity data evidence the antiferromagnetic ordering
of all samples. The Neel temperature linearly increases with Co2+ concentration
x. Curie-Weiss fits of the high temperature susceptibility indicate that the
magnetic frustration decreases with x. The derived magnetic structure of
Mn3TeO6 can be described as an incommensurately modulated magnetic spin state
with k = [0, 0, kz] and an elliptical spin- spiral order of spins within the
chains of MnO6 octahedra. With increasing Co2+ concentration the propagation
vector kz changes from 0.453 (x = 0) to 0.516 (x = 2.4). The magnetic
anisotropy changes as well, leading to a reorientation of the spiral-basal
plane. A possible coexistence of long-range order of electrical dipoles and
magnetic moments in Mn3-xCoxTeO6 is discussed.
Chinese: 研究了Co2+掺杂对多铁性反铁磁体Mn3TeO6的结构、磁性和介电性质的影响。通过固态反应路线制备了固溶体系列Mn3-xCoxTeO6的陶瓷样品。将X射线和中子粉末衍射以及电子显微镜技术结合热力学、介电和磁测量，以研究晶体结构和物理性质随温度和组成的依赖关系。结果表明，x值高达2.4的化合物在5-295 K的温度范围内都采用纯Mn3TeO6的三方刚玉相关结构（空间群R-3），并且晶格参数a和c以及晶胞体积V随Co2+浓度的增加而线性减小。低温磁化率和热容量数据证实了所有样品的反铁磁性序。Neel温度随Co2+浓度x线性增加。高温磁化率的居里-韦斯拟合表明，随着x的增加，磁阻尼减小。Mn3TeO6的推导出的磁结构可以描述为具有k = [0, 0, kz]的不规则调制磁自旋状态，以及MnO6八面体链内自旋的椭圆自旋螺旋序。随着Co2+浓度的增加，传播矢量kz从0.453（x = 0）变为0.516（x = 2.4）。磁性各向异性也发生变化，导致螺旋基面重新取向。讨论了Mn3-xCoxTeO6中可能存在的电偶极矩和磁矩的长程有序共存。
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English: By assuming that tau protein can be in seven kinetic states, we developed a
model of tau protein transport in the axon and in the axon initial segment
(AIS). Two separate sets of kinetic constants were determined, one in the axon
and the other in the AIS. This was done by fitting the model predictions in the
axon with experimental results and by fitting the model predictions in the AIS
with the assumed linear increase of the total tau concentration in the AIS. The
calibrated model was used to make predictions about tau transport in the axon
and in the AIS. To the best of our knowledge, this is the first paper that
presents a mathematical model of tau transport in the AIS. Our modeling results
suggest that binding of free tau to MTs creates a negative gradient of free tau
in the AIS. This leads to diffusion-driven tau transport from the soma into the
AIS. The model further suggests that slow axonal transport and diffusion-driven
transport of tau work together in the AIS, moving tau anterogradely. Our
numerical results predict an interplay between these two mechanisms: as the
distance from the soma increases, the diffusion-driven transport decreases,
while motor-driven transport becomes larger. Thus, the machinery in the AIS
works as a pump, moving tau into the axon.
Chinese: 通过假设tau蛋白可以处于七个动力学状态，我们开发了一个tau蛋白在轴突和轴突起始段（AIS）中的运输模型。确定了两组独立的动力学常数，一组在轴突中，另一组在AIS中。这是通过将模型在轴突中的预测与实验结果相拟合，以及将模型在AIS中的预测与AIS中tau总浓度的假设线性增加相拟合来实现的。校准后的模型被用来预测tau在轴突和AIS中的运输。据我们所知，这是第一篇提出AIS中tau运输数学模型的论文。我们的建模结果表明，自由tau与微管蛋白的结合在AIS中产生自由tau的负梯度。这导致从细胞体到AIS的扩散驱动的tau运输。该模型进一步表明，慢速轴突运输和扩散驱动的tau运输在AIS中协同作用，将tau向前运输。我们的数值结果表明，这两种机制之间存在相互作用：随着从细胞体的距离增加，扩散驱动的运输减少，而动力驱动的运输增加。因此，AIS中的机制像一个泵，将tau运输到轴突中。
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English: We study the Loschmidt echo and Berry phase in a nonlinear system transported
around a double and triple degeneracy. The nonlinearity of the system makes the
Berry phase different from that in linear systems. We propose a witness of
nonlinearity for the nonlinear system and show its dependence on the parameters
of the system, taking the standard Landau-Zener model as an example. We
calculate the Loschmidt echo(LE) or quantum fidelity in the quantum dynamics
under perturbations around the degeneracy, and establish a connection between
the LE and the witness of nonlinearity. These phases and Loschmidt echo can be
observed with current experimental technology in a nonlinear resonator.
Chinese: 我们研究了一个在双简并和三简并处被运输的非线性系统中的Loschmidt回声和Berry相位。系统的非线性使得Berry相位与线性系统中的不同。我们为非线性系统提出了一种非线性证伪方法，并展示了它与系统参数之间的依赖关系，以标准的Landau-Zener模型为例。我们计算了在简并处受到扰动的量子动力学中的Loschmidt回声(LE)或量子 fidelity，并建立了LE与非线性证伪方法之间的联系。这些相位和Loschmidt回声可以通过当前的实验技术在非线性谐振器中观察到。
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English: We obtain upper bounds (in most cases, sharp) for the hitting times of random
walks on finite undirected graphs expressed as functions of the graph's number
of edges. In particular, we show that the maximum hitting time for a simple
random walk on a connected graph with $m$ edges is at most $m^2$. Similar
bounds are given for the settings involving arbitrary edge-weight and edge-cost
functions. Upper bounds of this type are especially useful for sparse graphs.
Chinese: 我们得到了有限无向图上随机游走达到时间（在大多数情况下，为最佳上界）的上界，并将其表示为图边数的函数。特别是，我们证明了在具有 $m$ 条边的连通图上简单随机游走的最大达到时间至多为 $m^2$。对于涉及任意边权重和边成本函数的设置，也给出了类似的界限。这类上界对于稀疏图尤其有用。
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English: Convolutional Architecture for Fast Feature Encoding (CAFFE) [11] is a
software package for the training, classifying, and feature extraction of
images. The UCF Sports Action dataset is a widely used machine learning dataset
that has 200 videos taken in 720x480 resolution of 9 different sporting
activities: diving, golf, swinging, kicking, lifting, horseback riding,
running, skateboarding, swinging (various gymnastics), and walking. In this
report we report on a caffe feature extraction pipeline of images taken from
the videos of the UCF Sports Action dataset. A similar test was performed on
overfeat, and results were inferior to caffe. This study is intended to explore
the architecture and hyper parameters needed for effective static analysis of
action in videos and classification over a variety of image datasets.
Chinese: 卷积架构快速特征编码（CAFFE）[11]是一个用于图像训练、分类和特征提取的软件包。UCF运动动作数据集是一个广泛使用的机器学习数据集，包含9种不同运动活动的200个720x480分辨率的视频：跳水、高尔夫、挥杆、踢球、举重、骑马、跑步、滑板、挥杆（各种体操）和走路。在本报告中，我们报告了从UCF运动动作数据集的视频中提取图像的CAFFE特征提取流程。在overfeat上也进行了类似的测试，结果不如CAFFE。这项研究旨在探索用于视频动作有效静态分析和在各种图像数据集上进行分类所需的架构和超参数。
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English: In this paper, relying on known results on consistent Hermite-Pad\'e
approximations of a system of trigonometric series, sufficient conditions are
found under which linear Hermite-Chebyshev approximations exist and are
determined uniquely. When the found conditions are met, formulas describing the
explicit form of the numerators and denominator of linear Hermite-Pad\'e
approximations for a system of functions that are sums of Fourier series with
respect to Chebyshev polynomials of the first and second kind are obtained.
Chinese: 在这篇论文中，基于对系统三角级数一致Hermite-Padé逼近的已知结果，找到了线性Hermite-Chebyshev逼近存在且唯一确定的充分条件。当满足找到的条件时，得到了描述线性Hermite-Padé逼近的分子和分母的显式形式的公式，这些逼近适用于关于第一类和第二类Chebyshev多项式的傅里叶级数的函数之和的系统。
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English: The Poincar\'e gauge theory (PGT) of gravity provides a viable formulation of
general relativity (Einstein-Cartan theory), and a popular model-building
framework for modified gravity with torsion. Notoriously, however, the PGT
terms which propagate vector torsion lead to strongly-coupled ghosts: the
modern view is that only scalar torsion can propagate. To fix this, we revisit
the concept of embedding explicit mass scales in scale-invariant theories,
showing how the Klein-Gordon theory naturally leads to a slowly-rolling
inflaton. We then show that the unique scale-invariant embedding of PGT leads
to two new terms, one of which is the Maxwell term for vector torsion. We
provide the full spectrum of quantum particles in the resulting theory. Our
result means that every PGT is conformal and - after a two-decade hiatus -
vector torsion is back on the menu.
Chinese: 庞加莱规范理论（PGT）为广义相对论（爱因斯坦-卡特尔理论）提供了一个可行的公设，并且是构建具有扭率的修正引力的一个流行模型框架。然而，众所周知，传播矢量扭率的PGT项会导致强耦合鬼：现代观点认为只有标量扭率可以传播。为了解决这个问题，我们重新审视了在尺度不变理论中嵌入显式质量尺度的概念，展示了如何克莱因-戈登理论自然地导致缓慢滚动的暴胀子。然后我们表明，PGT的独特尺度不变嵌入导致两个新项，其中之一是矢量扭率的麦克斯韦项。我们提供了该理论中量子粒子的完整谱系。我们的结果表明，每个PGT都是共形的，并且在经过二十年的中断后，矢量扭率再次成为研究焦点。
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English: We introduce unbounded multipliers on operator spaces. These multipliers
generalize both, regular operators on Hilbert C*-modules and (bounded)
multipliers on operator spaces.
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Wir definieren den Begriff eines unbeschr\"ankten Multiplikators auf
Operatorr\"aumen. Diese Multiplikatoren verallgemeinern sowohl regul\"are
Operatoren auf Hilbert-C*-Moduln als auch (beschr\"ankte) Multiplikatoren auf
Operatorr\"aumen.
Chinese: 我们引入了算子空间上的无界乘子。这些乘子推广了希尔伯特C*-模上的正规算子和算子空间上的（有界）乘子。
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我们定义了算子空间上无界乘子的概念。这些乘子推广了希尔伯特C*-模上的正规算子和算子空间上的（有界）乘子。
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English: We numerically investigate the impact of GTR on the orbital part of the
satellite-to-satellite range \rho and range-rate \dot\rho of the twin GRACE A/B
spacecrafts through their dynamical equations of motion integrated in an
Earth-centered frame over a time span \Delta t=1 d. Instead, the GTR effects
connected with the propagation of the electromagnetic waves linking the
spacecrafts are neglected. The present-day accuracies in measuring the GRACE
biased range and range-rate are \sigma_\rho\sim 1-10 \mum, \sigma_\dot\rho\sim
0.1-1 \mum s^-1; studies for a follow-on of such a mission points toward a
range-rate accuracy of the order of \sigma_\dot\rho\sim 1 nm s^-1 or better.
The GTR range and range-rate effects turn out to be \Delta\rho=80 \mum and
\Delta\dot\rho=0.012 \mum s^-1 (Lense-Thirring), and \Delta\rho=6000 \mum and
\Delta\dot\rho=10 \mum s^-1 (Schwarzschild). We also compute the dynamical
range and range-rate perturbations caused by the first six zonal harmonic
coefficients J_L, L=2,3,4,5,6,7 of the classical multipolar expansion of the
terrestrial gravitational potential in order to evaluate their aliasing impact
on the relativistic effects. Conversely, we also quantitatively, and
preliminarily, assess the possible a-priori \virg{imprinting} of GTR itself,
not solved-for in all the GRACE-based Earth's gravity models produced so far,
on the estimated values of the low degree zonals of the geopotential. The
present sensitivity analysis can also be extended, in principle, to different
orbital configurations in order to design a suitable dedicated mission able to
accurately measure the relativistic effects considered.
Chinese: 我们通过在以地球为中心的坐标系中，对双星GRACE A/B航天器的轨道部分进行运动方程的数值积分，研究了广义相对论（GTR）对双星航天器之间的距离ρ和距离变化率\dot\rho的影响，积分时间跨度为\Delta t=1天。然而，与航天器之间电磁波传播相关的GTR效应被忽略。目前测量GRACE偏心距离和距离变化率的精度为\sigma_\rho\sim 1-10 \mum，\sigma_\dot\rho\sim 0.1-1 \mum s^-1；对这类任务的后续研究指出，距离变化率的精度可达\sigma_\dot\rho\sim 1 nm s^-1或更高。GTR的距离和距离变化率效应为\Delta\rho=80 \mum和\Delta\dot\rho=0.012 \mum s^-1（Lense-Thirring），以及\Delta\rho=6000 \mum和\Delta\dot\rho=10 \mum s^-1（Schwarzschild）。我们还计算了由经典多极展开中的前六个区域谐振系数J_L（L=2,3,4,5,6,7）引起的动力学距离和距离变化率扰动，以评估它们对相对论效应的混叠影响。相反，我们定量地、初步地评估了GTR本身可能存在的先验\virg{印记}，这在迄今为止所有基于GRACE的地球重力模型中尚未解决，对地势低阶区域估计值的影响。原则上，这种敏感性分析也可以扩展到不同的轨道配置，以设计一个能够准确测量所考虑的相对论效应的专用任务。
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English: In this paper, we consider the extended stochastic Navier-Stokes equations
with Caputo derivative driven by fractional Brownian motion. We firstly derive
the pathwise spatial and temporal regularity of the generalized
Ornstein-Uhlenbeck process. Then we discuss the existence, uniqueness, and
H\"{o}lder regularity of mild solutions to the given problem under certain
sufficient conditions, which depend on the fractional order $\alpha$ and Hurst
parameter $H$. The results obtained in this study improve some results in
existing literature.
Chinese: 在这篇论文中，我们考虑了由分数布朗运动驱动的Caputo导数扩展随机Navier-Stokes方程。我们首先推导了广义Ornstein-Uhlenbeck过程的路径空间和时间正则性。然后，我们在某些充分条件下讨论了给定问题的温和解的存在性、唯一性和Hölder正则性，这些条件依赖于分数阶$\alpha$和Hurst参数$H$。本研究获得的结果改进了现有文献中的一些结果。
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English: Gamma-Ray bursts, flaring active galactic nuclei and pulsars are distant and
energetic astrophysical sources, detected up to tens of TeV with Imaging
Atmospheric Cherenkov Telescopes (IACTs). Due to their high variability, they
are the most suitable sources for energy-dependent time-delay searches related
to Lorentz Invariance Violation (LIV) predicted by some Quantum Gravity (QG)
models. However, these studies require large datasets. A working group between
the three major IACTs ground experiments - H.E.S.S., MAGIC and VERITAS - has
been formed to address this issue and combine for the first time all the
relevant data collected by the three experiments in a joint analysis. This
proceeding will review the new standard combination method. The likelihood
technique used to deal with data from different source types and instruments
will be presented, as well as the way systematic uncertainties are taken into
account. The method has been developed and tested using simulations based on
published source observations from the three experiments. From these
simulations, the performance of the method will be assessed and new light will
be shed on time delays dependencies with redshift.
Chinese: 伽马射线暴、耀变活动星系核和脉冲星是遥远且能量巨大的天体物理源，其能量可达数十TeV，通过成像大气切伦科夫望远镜（IACTs）被探测到。由于它们的高变异性，它们是最适合进行与洛伦兹不变性违反（LIV）相关的能量依赖性时间延迟搜索的源，这是某些量子引力（QG）模型预测的。然而，这些研究需要大量数据集。在H.E.S.S.、MAGIC和VERITAS三个主要IACTs地面实验之间成立了一个工作组来解决这一问题，并首次将三个实验收集的所有相关数据在联合分析中进行结合。这一过程将回顾新的标准组合方法。将介绍用于处理不同源类型和仪器数据的似然技术，以及如何考虑系统不确定性。该方法已通过基于三个实验已发表的源观测模拟进行开发和测试。从这些模拟中，将评估该方法的表现，并对红移与时间延迟依赖性提供新的见解。
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English: Energy degeneracy in physical systems may be induced by symmetries of the
Hamiltonian, and the resonance of degeneracy states in carbon nanostructures
can effectively enhance the stability of the system. Combining the octet rule,
we introduce a parameter-free statistical model to determine the physical
properties by lifting the energy degeneracy in carbon nanostructures. This
model offers a direct path to accurately ascertain electron density
distributions in quantum systems, akin to how charge density is used in density
functional theory to deduce system properties. Our methodology diverges from
traditional quantum mechanics, focusing instead on this unique statistical
model by minimizing bonding free energy to determine the fundamental properties
of materials. Applied to carbon nanoclusters and graphynes, our model not only
precisely predicts bonding energies and electron density without relying on
external parameters, but also enhances the prediction of electronic structures
through bond occupancy numbers, which act as effective hopping integrals. This
innovation offers insights into the structural properties and quantum behavior
of electrons across various dimensions.
Chinese: 物理系统中能量的简并可能由哈密顿量的对称性引起，而在碳纳米结构中简并态的共振可以有效增强系统的稳定性。结合八隅体规则，我们引入一个无参数的统计模型，通过消除碳纳米结构中的能量简并来确定物理性质。该模型为准确确定量子系统中的电子密度分布提供了一条直接途径，类似于在密度泛函理论中如何使用电荷密度来推断系统性质。我们的方法与传统量子力学不同，而是专注于通过最小化键合自由能来确定材料的根本性质，从而采用这一独特的统计模型。将我们的模型应用于碳纳米簇和石墨烯，不仅能够精确预测键合能和电子密度，而不依赖于外部参数，而且还通过键占位数来增强对电子结构的预测，这些键占位数充当有效的跳跃积分。这一创新为洞察电子在不同维度上的结构性质和量子行为提供了见解。
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English: Results of the Spectral Quark Model for the gravitational, electromagnetic,
and transition form factors of the pion are discussed. In this model both the
parton distribution amplitude and the parton distribution function are flat, in
agreement with the transverse lattice calculations at low renormalization
scales. The model predictions for the gravitational form factor are compared to
the lattice data, with good agreement. We also find a remarkable relation
between the three form factors, holding within our model, which besides
reproducing the anomaly, provides a relation between radii which is reasonably
well fulfilled. Comparison with the CELLO, CLEO, and BaBar data for the
transition form factor is also considered.
Chinese: 讨论了谱夸克模型对π介子的引力形因子、电磁形因子和跃迁形因子的结果。在此模型中，部分子分布振幅和部分子分布函数都是平坦的，与低重整化尺度的横向格点计算结果一致。模型对引力形因子的预测与格点数据相比，吻合良好。我们还发现，在我们模型中存在一个显著的三个形因子之间的关系，该关系除了重现异常外，还提供了合理的半径关系。此外，还考虑了跃迁形因子与CELLO、CLEO和BaBar数据的比较。
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English: Recent technological advances have made it possible to build real-time,
interactive spoken dialogue systems for a wide variety of applications.
However, when users do not respect the limitations of such systems, performance
typically degrades. Although users differ with respect to their knowledge of
system limitations, and although different dialogue strategies make system
limitations more apparent to users, most current systems do not try to improve
performance by adapting dialogue behavior to individual users. This paper
presents an empirical evaluation of TOOT, an adaptable spoken dialogue system
for retrieving train schedules on the web. We conduct an experiment in which 20
users carry out 4 tasks with both adaptable and non-adaptable versions of TOOT,
resulting in a corpus of 80 dialogues. The values for a wide range of
evaluation measures are then extracted from this corpus. Our results show that
adaptable TOOT generally outperforms non-adaptable TOOT, and that the utility
of adaptation depends on TOOT's initial dialogue strategies.
Chinese: 近年来，技术的进步使得构建适用于各种应用的实时、交互式语音对话系统成为可能。然而，当用户不尊重这些系统的限制时，性能通常会下降。尽管用户在了解系统限制方面存在差异，而且不同的对话策略会使系统限制对用户更加明显，但大多数现有系统并没有尝试通过调整对话行为以适应个别用户来提高性能。本文对TOOT进行了实证评估，TOOT是一个可适应的语音对话系统，用于在网络上检索火车时刻表。我们进行了一项实验，其中20名用户使用TOOT的可适应和非可适应版本完成4项任务，从而产生了80个对话的语料库。然后从该语料库中提取了广泛评价措施的价值。我们的结果表明，可适应的TOOT通常优于非可适应的TOOT，并且适应的效用取决于TOOT的初始对话策略。
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English: Recent randomised clinical trials have shown that patients with ischaemic
stroke {due to occlusion of a large intracranial blood vessel} benefit from
endovascular thrombectomy. However, predicting outcome of treatment in an
individual patient remains a challenge. We propose a novel deep learning
approach to directly exploit multimodal data (clinical metadata information,
imaging data, and imaging biomarkers extracted from images) to estimate the
success of endovascular treatment. We incorporate an attention mechanism in our
architecture to model global feature inter-dependencies, both channel-wise and
spatially. We perform comparative experiments using unimodal and multimodal
data, to predict functional outcome (modified Rankin Scale score, mRS) and
achieve 0.75 AUC for dichotomised mRS scores and 0.35 classification accuracy
for individual mRS scores.
Chinese: 近期随机临床试验表明，由于大颅内血管阻塞导致的缺血性中风患者，从血管内血栓切除术治疗中获益。然而，预测单个患者的治疗效果仍然是一个挑战。我们提出了一种新颖的深度学习方法，直接利用多模态数据（临床元数据信息、影像数据以及从影像中提取的影像生物标志物）来估计血管内治疗的成功率。我们在我们的架构中集成了注意力机制，以建模通道和空间上的全局特征相互依赖性。我们使用单模态和多模态数据进行比较实验，以预测功能结果（改良Rankin量表评分，mRS）并实现二分类mRS评分的0.75 AUC和单个mRS评分的0.35分类准确率。
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English: In this paper, we present a new dataset of music performance videos which can
be used for training machine learning methods for multiple tasks such as
audio-visual blind source separation and localization, cross-modal
correspondences, cross-modal generation and, in general, any audio-visual
self-supervised task. These videos, gathered from YouTube, consist of solo
musical performances of 13 different instruments. Compared to previously
proposed audio-visual datasets, Solos is cleaner since a big amount of its
recordings are auditions and manually checked recordings, ensuring there is no
background noise nor effects added in the video post-processing. Besides, it
is, up to the best of our knowledge, the only dataset that contains the whole
set of instruments present in the URMP\cite{URPM} dataset, a high-quality
dataset of 44 audio-visual recordings of multi-instrument classical music
pieces with individual audio tracks. URMP was intented to be used for source
separation, thus, we evaluate the performance on the URMP dataset of two
different source-separation models trained on Solos. The dataset is publicly
available at https://juanfmontesinos.github.io/Solos/
Chinese: 在本文中，我们提出了一组新的音乐表演视频数据集，该数据集可用于训练机器学习方法，以完成多项任务，如音频-视觉盲源分离和定位、跨模态对应、跨模态生成以及一般意义上的任何音频-视觉自监督任务。这些视频是从YouTube收集的，包括13种不同乐器的独奏音乐表演。与之前提出的音频-视觉数据集相比，Solos更加干净，因为其中很大一部分录音是试听和人工检查的录音，确保在视频后期处理中没有添加背景噪音或效果。此外，据我们所知，这是唯一一个包含URMP数据集中所有乐器完整集合的数据集，URMP是一个高质量的多乐器古典音乐作品音频-视觉录音数据集，包含单独的音频轨道。URMP旨在用于源分离，因此，我们评估了在Solos上训练的两个不同源分离模型在URMP数据集上的性能。该数据集可在https://juanfmontesinos.github.io/Solos/公开获取。
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English: Many real-world data can be modeled as 3D graphs, but learning
representations that incorporates 3D information completely and efficiently is
challenging. Existing methods either use partial 3D information, or suffer from
excessive computational cost. To incorporate 3D information completely and
efficiently, we propose a novel message passing scheme that operates within
1-hop neighborhood. Our method guarantees full completeness of 3D information
on 3D graphs by achieving global and local completeness. Notably, we propose
the important rotation angles to fulfill global completeness. Additionally, we
show that our method is orders of magnitude faster than prior methods. We
provide rigorous proof of completeness and analysis of time complexity for our
methods. As molecules are in essence quantum systems, we build the
\underline{com}plete and \underline{e}fficient graph neural network (ComENet)
by combing quantum inspired basis functions and the proposed message passing
scheme. Experimental results demonstrate the capability and efficiency of
ComENet, especially on real-world datasets that are large in both numbers and
sizes of graphs. Our code is publicly available as part of the DIG library
(\url{https://github.com/divelab/DIG}).
Chinese: 许多现实世界数据可以建模为3D图，但学习完全且高效地包含3D信息的表示方法具有挑战性。现有方法要么使用部分3D信息，要么存在过高的计算成本。为完全且高效地包含3D信息，我们提出一种作用于1跳邻域的新型消息传递方案。我们的方法通过实现全局完整性和局部完整性，确保3D图上的3D信息完整性。值得注意的是，我们提出了重要的旋转角度以实现全局完整性。此外，我们证明我们的方法比现有方法快数量级。我们为我们的方法提供了完整性的严格证明和时间复杂度分析。由于分子本质上是量子系统，我们通过结合量子启发式基函数和提出的消息传递方案构建了\underline{com}plete和\underline{e}fficient图神经网络（ComENet）。实验结果表明ComENet的能力和效率，特别是在图数量和规模都很大的现实世界数据集上。我们的代码作为DIG库的一部分公开可用（\url{https://github.com/divelab/DIG}）。
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English: The persistent spin helix (PSH) that has been widely and exclusively studied
in zinc-blende structures is revealed for the first time on the surface of a
wurtzite structure. Through first-principles calculations of the ZnO(10-10)
surface, a quasi-one dimensional orientation of the spin textures is
identified. Further, the wavelength of this particular PSH is smaller than that
observed with various zinc-blende quantum well structures, thus indicating that
wurtzite-structured surfaces are suitable for spintronics applications.
Chinese: 首次在纤锌矿结构表面揭示了广泛且独属于闪锌矿结构的持久自旋螺旋（PSH）。通过对ZnO(10-10)表面的第一性原理计算，确定了自旋纹理的准一维取向。此外，这种特定PSH的波长小于在各种闪锌矿量子阱结构中观察到的波长，因此表明纤锌矿结构表面适用于自旋电子学应用。
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English: Imaging energy filters in photoelectron microscopes and momentum microscopes
employ spherical fields with deflection angles of 90{\deg}, 180{\deg} and even
2 x 180{\deg}. These instruments are optimized for high energy resolution, yet
they come along with image aberrations when they are operated in high
transmission mode with medium energy resolution. Here we present a new approach
for bandpass-filtered imaging in real or reciprocal space, using an asymmetric
electrostatic dodecapole. This multipole enables energy-dispersive beam
deflection and correction of image aberrations up to the 3rd order. Owing to a
deflection angle of only 4{\deg}, the total beam displacement in the filter is
just ~10 mm. Hence, the entire instrument is compact and just requires a
straight vacuum tube. The multipole is framed by transfer lenses in the
entrance and exit branch. Two sets of 16 entrance and exit apertures with
different sizes on piezomotor-driven holders allow selecting the desired
resolution. The combination of apertures and dodecapole acts as a bandpass
pre-selector in a high-energy time-of-flight momentum microscope at the hard
X-ray beamline P22 at PETRA-III (DESY, Hamburg). At pass energies between 400
and 600 eV it transmits electrons with kinetic energies in the range of 20-40
eV and thus effectively eliminates unwanted intensity from higher-energy
electrons in the ToF analyzer. At low pass energies, the instrument allows
energy-filtered imaging without subsequent ToF analysis. In a laboratory
experiment the 4{\deg} prototype reached < 500 meV resolution, which is
sufficient for fast survey studies in the X-ray range.
Chinese: 在光电子显微镜和动量显微镜中，能量滤波器采用90°、180°甚至2×180°偏转角的球形场。这些仪器在高中能分辨率的高透射模式下工作时，会产生图像像差。这里我们提出了一种在实空间或倒易空间中进行带通滤波成像的新方法，使用非对称静电十二极。这种多极能够实现能量色散光束偏转和高达三阶的图像像差校正。由于偏转角仅为4°，滤波器中的总光束位移仅为~10毫米。因此，整个仪器结构紧凑，仅需一根直真空管。多极由入口和出口分支中的传输透镜包围。两个由压电电机驱动的、具有不同尺寸的16组入口和出口孔径允许选择所需的分辨率。孔径和多极的组合在高能飞行时间动量显微镜中充当带通预选择器，该显微镜位于PETRA-III（DESY，汉堡）的硬X射线光束线P22上。在400至600 eV的透射能量范围内，它传输20-40 eV动能范围的电子，从而有效地消除了飞行时间分析器中高能电子的不必要强度。在低透射能量下，该仪器允许进行能量滤波成像，无需后续飞行时间分析。在实验室实验中，4°原型达到了<500 meV的分辨率，这对于X射线范围内的快速扫描研究是足够的。
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English: The realization of Haldane's topological graphene model in practical
materials has presented significant challenges. Here, we propose achieving this
model by embedding graphene in chiral cavities, using the asymptotically
decoupled framework detailed in Ref. [Phys. Rev. Lett. 126, 153603 (2021)].
Additionally, we introduce an equilibrium strategy for achieving valley
polarization in this system with C2-symmetry breaking. Through numerical
methods, we quantify the locking of photon numbers with Bloch electrons and
calculate the topology-induced imbalance of valley photons. Furthermore, we
elucidate that topological phase transition is characterized by the sign change
of photon numbers during interband excitation. These findings underscore the
remarkable potential of utilizing cavity quantum fluctuations to engineer
electronic and photonic properties specific to valleys and topologies,
particularly within the realm of strong light-matter coupling.
Chinese: 实现霍尔丹拓扑石墨烯模型的实际材料中已面临重大挑战。在这里，我们提出通过在具有C2对称性破坏的旋光腔中嵌入石墨烯来实现这一模型，具体参考了[Phys. Rev. Lett. 126, 153603 (2021)]中详述的渐近解耦框架。此外，我们还引入了一种实现该系统中谷极化的平衡策略。通过数值方法，我们量化了光子数与布洛赫电子的锁定，并计算了拓扑诱导的谷光子不平衡。此外，我们阐明了在带间激发过程中，拓扑相变是由光子数的符号变化来表征的。这些发现突显了利用腔量子涨落来工程特定于谷和拓扑的电子和光子性质，特别是在强光-物质耦合领域内的巨大潜力。
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English: Data processing systems impose multiple views on data as it is processed by
the system. These views include spreadsheets, databases, matrices, and graphs.
Associative arrays unify and simplify these different approaches into a common
two-dimensional view of data. Graph construction, a fundamental operation in
the data processing pipeline, is typically done by multiplying the incidence
array representations of a graph, $\mathbf{E}_\mathrm{in}$ and
$\mathbf{E}_\mathrm{out}$, to produce an adjacency matrix of the graph that can
be processed with a variety of machine learning clustering techniques. This
work focuses on establishing the mathematical criteria to ensure that the
matrix product $\mathbf{E}_\mathrm{out}^\intercal\mathbf{E}_\mathrm{in}$ is the
adjacency array of the graph. It will then be shown that these criteria are
also necessary and sufficient for the remaining nonzero product of incidence
arrays, $\mathbf{E}_\mathrm{in}^\intercal\mathbf{E}_\mathrm{out}$ to be the
adjacency matrices of the reversed graph. Algebraic structures that comply with
the criteria will be identified and discussed.
Chinese: 数据处理系统在数据处理过程中对数据呈现多种视图。这些视图包括电子表格、数据库、矩阵和图表。关联数组将这些不同的方法统一和简化为一个共同的数据二维视图。图构建是数据处理管道中的基本操作，通常通过乘以图的入射数组表示 $\mathbf{E}_\mathrm{in}$ 和 $\mathbf{E}_\mathrm{out}$ 来完成，以产生一个图邻接矩阵，该矩阵可以用各种机器学习聚类技术进行处理。这项工作侧重于建立数学标准，以确保矩阵乘积 $\mathbf{E}_\mathrm{out}^\intercal\mathbf{E}_\mathrm{in}$ 是图的邻接数组。然后，将证明这些标准对于剩余的非零乘积 $\mathbf{E}_\mathrm{in}^\intercal\mathbf{E}_\mathrm{out}$ 成为反转图的邻接矩阵也是必要且充分的。将识别并讨论符合这些标准的代数结构。
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English: The Large Synoptic Survey Telescope (LSST) has been designed in order to
satisfy several different scientific objectives that can be addressed by a
ten-year synoptic sky survey. However, LSST will also provide a large amount of
data that can then be exploited for additional science beyond its primary
goals. We demonstrate the potential of using LSST data to search for transiting
exoplanets, and in particular to find planets orbiting host stars that are
members of stellar populations that have been less thoroughly probed by current
exoplanet surveys. We find that existing algorithms can detect in simulated
LSST light curves the transits of Hot Jupiters around solar-type stars, Hot
Neptunes around K dwarfs, and planets orbiting stars in the Large Magellanic
Cloud. We also show that LSST would have the sensitivity to potentially detect
Super-Earths orbiting red dwarfs, including those in habitable zone orbits, if
they are present in some fields that LSST will observe. From these results, we
make the case that LSST has the ability to provide a valuable contribution to
exoplanet science.
Chinese: 大型综合巡天望远镜（LSST）的设计旨在满足多个不同的科学目标，这些目标可以通过为期十年的综合天体巡天来达成。然而，LSST还将提供大量数据，这些数据可以用于实现其主目标之外的额外科学研究。我们展示了利用LSST数据搜寻系外行星的潜力，特别是寻找那些在当前系外行星调查中探测较少的恒星宿主星周围的行星。我们发现，现有的算法可以在模拟的LSST光变曲线上检测到围绕太阳型恒星的热木星、围绕K型矮星的热海王星，以及围绕大麦哲伦云中恒星运行的行星。我们还表明，如果这些行星存在于LSST将要观测的一些区域，LSST将具有检测围绕红矮星的超级地球（包括那些位于宜居带轨道上的）的灵敏度。基于这些结果，我们提出LSST有能力为系外行星科学做出宝贵的贡献。
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English: Normalizing Flows are generative models which produce tractable distributions
where both sampling and density evaluation can be efficient and exact. The goal
of this survey article is to give a coherent and comprehensive review of the
literature around the construction and use of Normalizing Flows for
distribution learning. We aim to provide context and explanation of the models,
review current state-of-the-art literature, and identify open questions and
promising future directions.
Chinese: 标准化流是一类生成模型，它们产生可处理的分布，其中采样和密度评估都可以高效且精确。本综述文章的目的是对围绕标准化流构建和用于分布学习的文献进行连贯和全面的回顾。我们旨在提供模型背景和解释，回顾当前最先进的研究文献，并确定开放性问题及有希望的未来研究方向。
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English: We study the spin dynamics of two dimensional electron gases (2DEGs) with
Rashba spin-orbit coupling by taking account of electron-electron interactions.
The diffusion equations for charge and spin densities are derived by making use
of the path-integral approach and the quasiclassical Green's function.
Analyzing the effect of the interactions, we show that the spin-relaxation time
can be enhanced by the electron-electron interaction in the ballistic regime.
Chinese: 我们研究了具有Rashba自旋轨道耦合的两维电子气（2DEGs）的自旋动力学，同时考虑了电子-电子相互作用。通过使用路径积分方法和准经典格林函数，我们推导了电荷和自旋密度的扩散方程。分析相互作用的影响，我们表明在弹道传输模式下，电子-电子相互作用可以增强自旋弛豫时间。
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English: Bursts and flares are among the distinctive observational manifestations of
magnetars, isolated neutron stars endowed with an ultra-strong magnetic field
($B \approx 10^{14}$--$10^{15}$ G). It is believed that these events arise in a
hot electron-positron plasma which remains trapped within the closed magnetic
field lines. We developed a simple radiative transfer model to simulate
magnetar flare emission in the case of a steady trapped fireball. After
dividing the fireball surface in a number of plane-parallel slabs, the local
spectral and polarization properties are obtained integrating the radiative
transfer equations for the two normal modes. We assume that magnetic Thomson
scattering is the dominant source of opacity, and neglect contributions from
second-order radiative processes, although double-Compton scattering is
accounted for in establishing local thermal equilibrium in the fireball
atmospheric layers. The observed spectral and polarization properties as
measured by a distant observer are obtained summing the contributions from the
patches which are visible for a given viewing geometry by means of a
ray-tracing code. The spectra we obtained in the 1-100 keV energy range are
thermal and can be described in terms of the superposition of two blackbodies.
The blackbody temperature and the emitting area ratio are in broad agreement
with the available observations. The predicted linear polarization degree is in
general greater than 80% over the entire energy range and should be easily
detectable by new-generation X-ray polarimeters, like IXPE, XIPE and eXTP.
Chinese: 爆发和耀斑是磁星（具有超强磁场，$B \approx 10^{14}$--$10^{15}$ 高斯的孤立中子星）的独特观测现象。人们认为这些事件产生于被闭合磁场线困住的炽热电子-正电子等离子体中。我们开发了一个简单的辐射传输模型，用于模拟稳态被困火球中的磁星耀斑发射。将火球表面划分为多个平行平板后，通过积分两个正模的辐射传输方程，获得局部光谱和偏振特性。我们假设磁汤姆逊散射是Opacity的主要来源，并忽略二级辐射过程的影响，尽管在建立火球大气层局部热平衡时考虑了双康普顿散射。通过光线追踪代码，对给定观测几何下可见的斑块贡献进行求和，得到远处观测者测量的光谱和偏振特性。我们在1-100 keV能量范围内获得的光谱是热辐射的，可以用两个黑体的叠加来描述。黑体温度和发射面积比与现有观测结果基本一致。预测的线性偏振度在整个能量范围内通常大于80%，应能被新一代X射线偏振计（如IXPE、XIPE和eXTP）轻松探测到。
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English: Two new generalizations of the relation of comonotonicity of lattice-valued
vectors are introduced and discussed. These new relations coincide on
distributive lattices and they share several properties with the comonotonicity
for the real-valued vectors (which need not hold for $L$-valued vectors
comonotonicity, in general). Based on these newly introduced generalized types
of comonotonicity of $L$-valued vectors, several new axiomatizations of
$L$-valued Sugeno integrals are introduced. One of them brings a substantial
decrease of computational complexity when checking an aggregation function to
be a Sugeno integral.
Chinese: 介绍了两种关于格值向量共单调性的新推广，并对其进行了讨论。这些新关系在分配格上是一致的，并且它们与实值向量的共单调性共享几个性质（在一般情况下，这些性质对于 $L$-值向量的共单调性不一定成立）。基于这些新引入的 $L$-值向量共单调性的推广类型，介绍了 $L$-值 Sugeno 积分的几种新的公理化方法。其中之一在检查一个聚合函数是否为 Sugeno 积分时，显著降低了计算复杂性。
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English: This PhD thesis deals with some new models of intensional type theory and the
Univalence Axiom introduced by Vladimir Voevodsky. Our work takes place in the
framework of the definitions of type-theoretic fibration categories (the notion
of model under consideration in this thesis) and universe in a type-theoretic
fibration category, definitions due to Michael Shulman. The goal of this thesis
consists mainly in the exploration of the stability of the univalence axiom, in
particular in the following sense: being given a type-theoretic fibration
category C equipped with a univalent universe U, we are eager to endow the
functor category [D,C], where D is a small category, with the structure of a
type-theoretic fibration category plus a univalent universe.
Chinese: 这篇博士论文涉及一些关于内涵类型论的新模型以及由弗拉基米尔·沃沃德斯基提出的等价公理。我们的工作是在迈克尔·舒尔曼提出的类型论纤维范畴的定义（本论文中考虑的模型）和类型论纤维范畴中的宇宙定义的框架下进行的。本论文的目标主要在于探索等价公理的稳定性，特别是在以下意义上：给定一个配备了等价宇宙U的类型论纤维范畴C，我们渴望赋予小范畴D的函子范畴[D,C]类型论纤维范畴加上等价宇宙的结构。
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English: The statistical mechanics of spin models, such as the Ising or Potts models,
on generic random graphs can be formulated economically by considering the N
--> 1 limit of Hermitian matrix models. In this paper we consider the N --> 1
limit in complex matrix models, which describes vertex models of different
sorts living on random graphs. From the graph theoretic perspective one is
using matrix model and field theory inspired methods to count various classes
of directed graphs.
We also make some remarks on vertex models on planar random graphs (the N -->
infinity limit) where the resulting matrix models are not generally soluble
using currently known methods. Nonetheless, some particular cases may be mapped
onto known models and hence solved.
Chinese: 自旋模型（如伊辛模型或玻色模型）在通用随机图上的统计力学，可通过考虑厄米矩阵模型的N趋于1的极限来经济地表述。本文考虑复矩阵模型的N趋于1的极限，该极限描述了存在于随机图上的各类顶点模型。从图论视角来看，人们使用矩阵模型和场论启发的方法来计数各类有向图。此外，我们还对平面随机图（即N趋于无穷大的极限）上的顶点模型做了若干评论，其中得到的矩阵模型通常无法使用当前已知方法求解。尽管如此，某些特定情形可映射到已知模型，从而得到求解。
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English: The stochastic gravitational-wave backgrounds (SGWBs) for current detectors
are dominated by binary black-hole (BBH) and binary neutron-star (BNS)
coalescences. The sensitivity of current networks of gravitational-wave (GW)
detectors allows only a small fraction of BBHs and BNSs to be resolved and
subtracted, but previous work indicated that the situation should significantly
improve with next-generation (XG) observatories. We revisit these conclusions
by taking into account waveform-modeling uncertainties, updated astrophysical
models, and (crucially) the full set of parameters that must be estimated to
remove the resolved sources. Compared to previous studies, we find that the
residual background from BBHs and BNSs is large even with XG detector networks.
New data analysis methods will thus be required to observe the SGWB from cosmic
supernovae or contributions from early-Universe phenomena like cosmic strings,
stiff post-inflation fluids, or axion inflation.
Chinese: 当前探测器对于随机引力波背景（SGWBs）的探测主要受双黑洞（BBH）和双中子星（BNS）合并的影响。当前引力波（GW）探测器网络的灵敏度仅允许一小部分BBH和BN合并事件被解析和减去，但先前的研究表明，随着下一代（XG）观测站的建立，情况应该会有显著改善。我们通过考虑波形建模的不确定性、更新的天体物理模型以及（关键的是）必须估计以去除已解析源的全部参数，重新审视了这些结论。与先前的研究相比，我们发现即使使用XG探测器网络，BBH和BN合并事件产生的残余背景仍然很大。因此，需要新的数据分析方法来观察来自宇宙超新星或早期宇宙现象（如宇宙弦、刚性的后膨胀流体或轴子膨胀）对SGWB的贡献。
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