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English: This paper addresses the challenge of energy efficiency management faced by
intelligent IoT devices in complex application environments. A novel
optimization method is proposed, combining Deep Q-Network (DQN) with an edge
collaboration mechanism. The method builds a state-action-reward interaction
model and introduces edge nodes as intermediaries for state aggregation and
policy scheduling. This enables dynamic resource coordination and task
allocation among multiple devices. During the modeling process, device status,
task load, and network resources are jointly incorporated into the state space.
The DQN is used to approximate and learn the optimal scheduling strategy. To
enhance the model's ability to perceive inter-device relationships, a
collaborative graph structure is introduced to model the multi-device
environment and assist in decision optimization. Experiments are conducted
using real-world IoT data collected from the FastBee platform. Several
comparative and validation tests are performed, including energy efficiency
comparisons across different scheduling strategies, robustness analysis under
varying task loads, and evaluation of state dimension impacts on policy
convergence speed. The results show that the proposed method outperforms
existing baseline approaches in terms of average energy consumption, processing
latency, and resource utilization. This confirms its effectiveness and
practicality in intelligent IoT scenarios.
Chinese: 本文针对智能物联网设备在复杂应用环境中面临的能效管理挑战，提出了一种结合深度Q网络（DQN）与边缘协作机制的新型优化方法。该方法构建了状态-动作-奖励交互模型，并引入边缘节点作为状态聚合和策略调度的中介。这使得多个设备之间能够进行动态资源协调和任务分配。在建模过程中，设备状态、任务负载和网络资源被共同纳入状态空间。DQN被用来近似和学习的最佳调度策略。为了增强模型感知设备间关系的能力，引入了一种协作图结构来建模多设备环境，并协助决策优化。使用FastBee平台收集的实际物联网数据进行了实验。进行了包括不同调度策略下的能效比较、任务负载变化下的鲁棒性分析以及状态维度对策略收敛速度影响评估在内的多组比较和验证测试。结果表明，所提出的方法在平均能耗、处理延迟和资源利用率方面优于现有的基准方法。这证实了其在智能物联网场景中的有效性和实用性。
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English: Passive network tomography uses end-to-end observations of network
communication to characterize the network, for instance to estimate the network
topology and to localize random or adversarial glitches. Under the setting of
linear network coding this work provides a comprehensive study of passive
network tomography in the presence of network (random or adversarial) glitches.
To be concrete, this work is developed along two directions: 1. Tomographic
upper and lower bounds (i.e., the most adverse conditions in each problem
setting under which network tomography is possible, and corresponding schemes
(computationally efficient, if possible) that achieve this performance) are
presented for random linear network coding (RLNC). We consider RLNC designed
with common randomness, i.e., the receiver knows the random code-books all
nodes. (To justify this, we show an upper bound for the problem of topology
estimation in networks using RLNC without common randomness.) In this setting
we present the first set of algorithms that characterize the network topology
exactly. Our algorithm for topology estimation with random network errors has
time complexity that is polynomial in network parameters. For the problem of
network error localization given the topology information, we present the first
computationally tractable algorithm to localize random errors, and prove it is
computationally intractable to localize adversarial errors. 2. New network
coding schemes are designed that improve the tomographic performance of RLNC
while maintaining the desirable low-complexity, throughput-optimal, distributed
linear network coding properties of RLNC. In particular, we design network
codes based on Reed-Solomon codes so that a maximal number of adversarial
errors can be localized in a computationally efficient manner even without the
information of network topology.
Chinese: 被动网络断层成像利用网络通信的端到端观测来表征网络，例如，用于估计网络拓扑并定位随机或敌对的故障。在线性网络编码的设置下，本文提供了在存在网络（随机或敌对）故障的情况下对被动网络断层成像的全面研究。具体而言，本文沿两个方向发展：1. 对随机线性网络编码（RLNC）的每个问题设置下可能的最不利条件进行了拓扑成像的上界和下界（即在拓扑成像可能的情况下每个问题设置下的最不利条件，以及相应的方案（如果可能的话，计算效率高）实现此性能）进行了呈现。我们考虑的是使用共同随机性的RLNC设计，即接收器知道所有节点的随机编码库。（为了证明这一点，我们展示了在不使用共同随机性的网络中使用RLNC进行拓扑估计的问题的上界。）在这种设置下，我们提出了第一个能够精确表征网络拓扑的算法。我们用于使用随机网络错误进行拓扑估计的算法的时间复杂度是网络参数的多项式。对于给定拓扑信息的网络错误定位问题，我们提出了第一个计算上可处理的算法来定位随机错误，并证明了定位敌对错误在计算上是不可处理的。2. 设计了新的网络编码方案，这些方案在保持RLNC的低复杂度、吞吐量最优、分布式线性网络编码的优良属性的同时，提高了拓扑成像性能。特别是，我们基于Reed-Solomon码设计网络编码，以便即使没有网络拓扑信息，也能在计算上高效地定位最大数量的敌对错误。
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English: Polymer adsorption on fractally rough walls of varying dimensionality is
studied by renormalization group methods on hierarchical lattices. Exact
results are obtained for deterministic walls. The adsorption transition is
found continuous for low dimension $d_w$ of the adsorbing wall and the
corresponding crossover exponent $\phi$ monotonically increases with $d_w$,
eventually overcoming previously conjectured bounds. For $d_w$ exceeding a
threshold value $d_w^*$, $\phi$ becomes 1 and the transition turns
first--order. $d_w^*>d_{saw}$, the fractal dimension of the polymer in the
bulk. An accurate numerical approach to the same problem with random walls
gives evidence of the same scenario.
Chinese: 研究了在具有不同维数分形粗糙壁上的聚合物吸附，使用层次化格点上的重整化群方法。对于确定性壁面，得到了精确结果。吸附相变在低维数$d_w$的吸附壁面处发现是连续的，相应的交叉指数$\phi$随着$d_w$单调增加，最终克服了先前假定的界限。当$d_w$超过一个阈值$d_w^*$时，$\phi$变为1，相变转变为一级。$d_w^*>d_{saw}$，即聚合物在主体中的分形维数。对于具有随机壁面的相同问题的准确数值方法，给出了相同场景的证据。
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English: A nonequilibrium system is characterized by a set of thermodynamic forces and
fluxes which give rise to entropy production (EP). We show that these forces
and fluxes have an information-geometric structure, which allows us to
decompose EP into contributions from different types of forces in general
(linear and nonlinear) discrete systems. We focus on the excess and
housekeeping decomposition, which separates contributions from conservative and
nonconservative forces. Unlike the Hatano-Sasa decomposition, our
housekeeping/excess terms are always well-defined, including in systems with
odd variables and nonlinear systems without steady states. Our decomposition
leads to far-from-equilibrium thermodynamic uncertainty relations and speed
limits. As an illustration, we derive a thermodynamic bound on the time
necessary for one cycle in a chemical oscillator.
Chinese: 一个非平衡系统由一组热力学力和通量组成，这些力和通量导致熵产生（EP）。我们表明，这些力和通量具有信息几何结构，这使得我们能够将EP分解为来自不同类型力（一般而言，线性和非线性）的离散系统的贡献。我们关注过剩和管家分解，它将保守力和非保守力的贡献分开。与Hatano-Sasa分解不同，我们的管家/过剩项总是有明确定义的，包括在奇变量系统和没有稳态的非线性系统中。我们的分解导致远离平衡的热力学不确定性关系和速度限制。作为一个例子，我们推导出化学振荡器一个循环所需时间的热力学界限。
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English: We propose a privacy-preserving uplink over-the-air computation (AirComp)
method, termed FLORAS, for single-input single-output (SISO) wireless federated
learning (FL) systems. From the perspective of communication designs, FLORAS
eliminates the requirement of channel state information at the transmitters
(CSIT) by leveraging the properties of orthogonal sequences. From the privacy
perspective, we prove that FLORAS offers both item-level and client-level
differential privacy (DP) guarantees. Moreover, by properly adjusting the
system parameters, FLORAS can flexibly achieve different DP levels at no
additional cost. A new FL convergence bound is derived which, combined with the
privacy guarantees, allows for a smooth tradeoff between the achieved
convergence rate and differential privacy levels. Experimental results
demonstrate the advantages of FLORAS compared with the baseline AirComp method,
and validate that the analytical results can guide the design of
privacy-preserving FL with different tradeoff requirements on the model
convergence and privacy levels.
Chinese: 我们提出了一种用于单输入单输出（SISO）无线联邦学习（FL）系统的隐私保护空中计算（AirComp）方法，称为FLORAS。从通信设计的角度来看，FLORAS通过利用正交序列的特性消除了发射机处信道状态信息（CSIT）的需求。从隐私的角度来看，我们证明了FLORAS提供了项目级和客户端级的差分隐私（DP）保证。此外，通过适当调整系统参数，FLORAS可以在不增加额外成本的情况下灵活地实现不同的DP级别。推导出了一个新的FL收敛界，结合隐私保证，允许在实现的收敛速度和差分隐私级别之间进行平滑权衡。实验结果表明，与基线AirComp方法相比，FLORAS具有优势，并验证了分析结果可以指导设计具有不同模型收敛和隐私级别权衡需求的隐私保护FL。
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English: Let $H = H_0 + P$ denote the harmonic oscillator on $\mathbb{R}^d$ perturbed
by an isotropic pseudodifferential operator $P$ of order $1$ and let $U(t) =
\operatorname{exp}(- it H)$. We prove a Gutzwiller-Duistermaat-Guillemin type
trace formula for $\operatorname{Tr} U(t)$. The singularities occur at times $t
\in 2 \pi \mathbb{Z}$ and the coefficients involve the dynamics of the Hamilton
flow of the symbol $\sigma(P)$ on the space $\mathbb{CP}^{d-1}$ of harmonic
oscillator orbits of energy $1$. This is a novel kind of sub-principal symbol
effect on the trace. We generalize the averaging technique of Weinstein and
Guillemin to this order of perturbation, and then present two completely
different calculations of $\operatorname{Tr} U(t)$. The first proof directly
constructs a parametrix of $U(t)$ in the isotropic calculus, following earlier
work of Doll-Gannot-Wunsch. The second proof conjugates the trace to the
Bargmann-Fock setting, the order $1$ of the perturbation coincides with the
`central limit scaling' studied by Zelditch-Zhou for Toeplitz operators.
Chinese: 令 $H = H_0 + P$ 表示在 $\mathbb{R}^d$ 上的受各向同性伪微分算子 $P$ （阶数为 1）扰动的谐振子，并令 $U(t) = \operatorname{exp}(- it H)$。我们证明了 $\operatorname{Tr} U(t)$ 的一个 Gutzwiller-Duistermaat-Guillemin 类型的迹公式。奇点出现在时间 $t \in 2 \pi \mathbb{Z}$，系数涉及到 $\mathbb{CP}^{d-1}$ 空间中能量为 1 的谐振子轨道的符号 $\sigma(P)$ 的哈密顿流动力学。这是在迹上的一种新型的次主符号效应。我们将 Weinstein 和 Guillemin 的平均技术推广到这种扰动的阶数，然后提出了 $\operatorname{Tr} U(t)$ 的两种完全不同的计算方法。第一种证明直接在各向同性微积分中构造了 $U(t)$ 的一个参数化矩阵，遵循 Doll-Gannot-Wunsch 早期的工作。第二种证明将迹与 Bargmann-Fock 设置相共轭，扰动的阶数 1 与 Zelditch-Zhou 研究的 Toeplitz 算子的“中心极限缩放”相一致。
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English: We give a new proof of a slightly modified version of a result of
Queffelec--Rose, by constructing a linear basis for the $\mathrm{SL}(n)$ skein
algebra of the twice punctured sphere for any non-zero complex number $q$,
excluding finitely many roots of unity of small order. In particular, the skein
algebra is a commutative polynomial algebra in $n-1$ generators, where each
generator is represented by an explicit $\mathrm{SL}(n)$ web, without
crossings, on the surface. This includes the case $q=1$, where the skein
algebra is identified with the coordinate ring of the $\mathrm{SL}(n)$
character variety of the twice punctured sphere. The proof of both the spanning
and linear independence properties of the basis depends on the so-called
$\mathrm{SL}(n)$ quantum trace map, due originally to Bonahon--Wong in the case
$n=2$. Two consequences of our method are that the quantum trace map and the
so-called splitting map embed the polynomial algebra into the Fock--Goncharov
quantum higher Teichm\"uller space and the L\^{e}--Sikora stated skein algebra,
respectively, of the annulus. We end by discussing the relationship with
Fock--Goncharov duality.
Chinese: 我们给出了一种对Queffelec--Rose结果稍作修改的新证明，通过为任意非零复数$q$（排除有限个小阶单位根）构造双 punctured 球的 $\mathrm{SL}(n)$ 桥结代数的一个线性基。特别是，这个桥结代数是一个在 $n-1$ 个生成元上的交换多项式代数，每个生成元在表面上由一个没有交叉的显式 $\mathrm{SL}(n)$ 网表示。这包括 $q=1$ 的情况，此时桥结代数与双 punctured 球的 $\mathrm{SL}(n)$ 特征类的坐标环相对应。基的生成性和线性无关性的证明依赖于所谓的 $\mathrm{SL}(n)$ 量子迹映射，最初由Bonahon--Wong在 $n=2$ 的情况下提出。我们方法的两项后果是，量子迹映射和所谓的分裂映射分别将多项式代数嵌入到Fock--Goncharov量子高Teichmüller空间和圆环的L\^{e}--Sikora陈述的桥结代数中。我们最后讨论了与Fock--Goncharov对偶性的关系。
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English: Myocardial perfusion imaging (MPI) with single-photon emission computed
tomography (SPECT) is a widely used and cost-effective diagnostic tool for
coronary artery disease. However, the lengthy scanning time in this imaging
procedure can cause patient discomfort, motion artifacts, and potentially
inaccurate diagnoses due to misalignment between the SPECT scans and the
CT-scans which are acquired for attenuation compensation. Reducing projection
angles is a potential way to shorten scanning time, but this can adversely
impact the quality of the reconstructed images. To address this issue, we
propose a detection-task-specific deep-learning method for sparse-view MPI
SPECT images. This method integrates an observer loss term that penalizes the
loss of anthropomorphic channel features with the goal of improving performance
in perfusion defect-detection task. We observed that, on the task of detecting
myocardial perfusion defects, the proposed method yielded an area under the
receiver operating characteristic (ROC) curve (AUC) significantly larger than
the sparse-view protocol. Further, the proposed method was observed to be able
to restore the structure of the left ventricle wall, demonstrating ability to
overcome sparse-sampling artifacts. Our preliminary results motivate further
evaluations of the method.
Chinese: 心肌灌注显像（MPI）与单光子发射计算机断层扫描（SPECT）是一种广泛使用且成本效益高的冠脉疾病诊断工具。然而，该成像程序中较长的扫描时间可能会引起患者不适、运动伪影，以及由于SPECT扫描与用于衰减补偿获得的CT扫描之间的错位，可能导致诊断不准确。缩短投影角度是缩短扫描时间的一种潜在方法，但这可能会对重建图像的质量产生不利影响。为了解决这个问题，我们提出了一种针对检测任务特定的深度学习方法，用于稀疏视图MPI SPECT图像。这种方法将观察者损失项与惩罚人形通道特征丢失的目标相结合，旨在提高灌注缺陷检测任务中的性能。我们观察到，在检测心肌灌注缺陷的任务中，所提出的方法在接收者操作特征（ROC）曲线下面积（AUC）方面显著大于稀疏视图方案。此外，观察到所提出的方法能够恢复左心室壁的结构，展示了克服稀疏采样伪影的能力。我们的初步结果激励了对该方法进行进一步评估。
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English: We show that free QED is equivalent to the continuous-space-and-time limit of
Fermi and Bose lattice quantum cellular automata theories derived from quantum
random walks satisfying simple symmetry and unitarity conditions. In doing so
we define the Fermi and Bose theories in a unified manner using the usual
fermion internal space but a boson internal space that is six-dimensional. We
show that the reduction to a two-dimensional boson internal space (two helicity
states arising from spin-1 plus the photon transversality condition) comes from
restricting the quantum cellular automaton theory to positive energies. We
briefly examine common symmetries of quantum cellular automata, and how
time-reversal symmetry demands the existence of negative-energy solutions.
These solutions produce a tension in coupling the Fermi and Bose theories, in
which the strong locality of quantum cellular automata seems to require a
nonzero amplitude to produce negative-energy states, leading to an unphysical
cascade of negative-energy particles. However, we show in a 1D model that by
extending interactions over a larger (but finite) range it is possible to
exponentially suppress the production of negative-energy particles to the point
where they can be neglected.
Chinese: 我们证明了自由量子电动力学（QED）等价于从满足简单对称性和幺正性条件的量子随机游走推导出的费米子和玻色子晶格量子细胞自动机理论的连续时空极限。在此过程中，我们使用常规的费米子内部空间，但使用六维的玻色子内部空间，以统一的方式定义费米子和玻色子理论。我们证明，将量子细胞自动机理论约化为二维玻色子内部空间（由自旋-1产生的两个螺旋度态加上光子横向条件）源于将理论限制在正能量上。我们简要考察了量子细胞自动机的共同对称性，以及时间反演对称性如何要求存在负能量解。这些解在将费米子和玻色子理论耦合时产生张力，其中量子细胞自动机强烈的局域性似乎需要非零振幅来产生负能量态，从而导致非物理的负能量粒子级联。然而，我们在一维模型中表明，通过将相互作用扩展到更大的（但有限的）范围，可以指数级地抑制负能量粒子的产生，以至于可以忽略不计。
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English: We characterize the two-photon excitation of an ultracold gas of Rubidium
atoms to Rydberg states analysing the induced atomic losses from an optical
dipole trap. Extending the duration of the Rydberg excitation to several ms,
the ground state atoms are continuously coupled to the formed positively
charged plasma. In this regime we measure the $n$-dependence of the blockade
effect and we characterise the interaction of the excited states and the ground
state with the plasma. We also investigate the influence of the
quasi-electrostatic trapping potential on the system, confirming the validity
of the ponderomotive model for states with $20\leq n\leq 120$.
Chinese: 我们通过分析光学偶极阱中诱导的原子损失，表征了超冷铷原子气体对里德伯态的双光子激发。将里德伯激发的持续时间延长到数毫秒，基态原子持续耦合到形成的正电等离子体。在此区域内，我们测量了阻塞效应的$n$依赖性，并表征了激发态和基态与等离子体的相互作用。我们还研究了准静电陷阱势对系统的影响，证实了对于$20\leq n\leq 120$的态，ponderomotive模型的正确性。
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English: Two-dimensional (2D) carbon-based materials are promising candidates for
developing more efficient green energy conversion and storage technologies.
This study presents a new 2D carbon allotrope, DOTT-Carbon, characterized by
its distinctive and multi-ring structure featuring 12-, 8-, 4-, and 3-membered
rings of carbon atoms. We explore its structural, mechanical, and lithium-ion
storage properties by employing density functional theory and machine learning
simulations. Phonon calculations confirm its structural stability and ab initio
molecular dynamics simulations demonstrate its thermal resilience at elevated
temperatures. The material exhibits anisotropic mechanical properties, with
Young's modulus values varying between 280-330 GPa. DOTT-Carbon displays a
lithium-ion storage capacity of 446.28 mAh/g, complemented by a low diffusion
barrier (0.2-0.9 eV) and a high diffusion coefficient ($ > 1.0 \times 10^{-6}$
cm$^{2}$/s), possibly facilitating efficient lithium-ion transport. The stable
open circuit voltage of 0.28 V also indicates its suitability as an anode
material.
Chinese: 二维（2D）碳基材料是开发更高效的绿色能源转换和存储技术的有希望的候选者。本研究提出了一种新的二维碳同素异形体，称为DOTT-Carbon，其特征是具有独特的多环结构，包括12个、8个、4个和3个碳原子组成的环。我们通过使用密度泛函理论和机器学习模拟来探索其结构、机械性能和锂离子存储特性。声子计算确认了其结构稳定性，而从头算分子动力学模拟展示了其在高温下的热韧性。该材料表现出各向异性的机械性能，杨氏模量值在280-330 GPa之间变化。DOTT-Carbon表现出446.28 mAh/g的锂离子存储容量，辅以低扩散势垒（0.2-0.9 eV）和高扩散系数（>1.0 × 10^{-6} cm^{2}/s），可能有助于高效锂离子传输。稳定的开路电压为0.28 V也表明其作为阳极材料的适用性。
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English: In this paper we investigate central congruence of left quasigroups in the
sense of Freese and McKenzie \cite{comm} and we extend some known results for
quandles. In particular, we can extend the characterization of finite nilpotent
latin quandles and the characterization of distributive varieties of quandles
to the setting of idempotent left quasigroups.
Chinese: 在这篇论文中，我们根据Freese和McKenzie的定义（见参考文献\cite{comm}）研究了左拟群的中心共轭，并扩展了一些关于拟群的已知结果。特别是，我们可以将有限幂零拉丁拟群的刻画以及拟群分配类的刻画扩展到幂等左拟群的环境中。
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English: Intelligent transport systems (ITS) are pivotal in the development of
sustainable and green urban living. ITS is data-driven and enabled by the
profusion of sensors ranging from pneumatic tubes to smart cameras. This work
explores a novel data source based on optical fibre-based distributed acoustic
sensors (DAS) for traffic analysis. Detecting the type of vehicle and
estimating the occupancy of vehicles are prime concerns in ITS. The first is
motivated by the need for tracking, controlling, and forecasting traffic flow.
The second targets the regulation of high occupancy vehicle lanes in an attempt
to reduce emissions and congestion. These tasks are often conducted by
individuals inspecting vehicles or through the use of emerging computer vision
technologies. The former is not scale-able nor efficient whereas the latter is
intrusive to passengers' privacy. To this end, we propose a deep learning
technique to analyse DAS signals to address this challenge through continuous
sensing and without exposing personal information. We propose a deep learning
method for processing DAS signals and achieve 92% vehicle classification
accuracy and 92-97% in occupancy detection based on DAS data collected under
controlled conditions.
Chinese: 智能交通系统（ITS）在可持续和绿色城市生活的发展中起着关键作用。ITS是数据驱动的，并由从气压管道到智能摄像头的各种传感器的大量存在所驱动。这项工作探索了一种基于光纤分布式声学传感器（DAS）的新型数据源，用于交通分析。在ITS中，检测车辆类型和估计车辆占用率是首要关注的问题。前者是由跟踪、控制和预测交通流量的需求所驱动的。后者旨在通过调节高占用率车辆车道来减少排放和拥堵。这些任务通常由检查车辆的个体或通过使用新兴的计算机视觉技术来完成。前者不可扩展且效率低下，而后者侵犯了乘客的隐私。为此，我们提出了一种深度学习技术，通过连续传感而不暴露个人信息来应对这一挑战。我们提出了一种处理DAS信号的深度学习方法，并在受控条件下收集的DAS数据上实现了92%的车辆分类准确率和92-97%的占用率检测。
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English: Transformer-based models have achieved stateof-the-art results in many tasks
in natural language processing. However, such models are usually slow at
inference time, making deployment difficult. In this paper, we develop an
efficient algorithm to search for fast models while maintaining model quality.
We describe a novel approach to decompose the Transformer architecture into
smaller components, and propose a sampling-based one-shot architecture search
method to find an optimal model for inference. The model search process is more
efficient than alternatives, adding only a small overhead to training time. By
applying our methods to BERT-base architectures, we achieve 10% to 30% speedup
for pre-trained BERT and 70% speedup on top of a previous state-of-the-art
distilled BERT model on Cloud TPU-v2 with a generally acceptable drop in
performance.
Chinese: 基于Transformer的模型在自然语言处理的许多任务中取得了最先进的结果。然而，这类模型在推理时通常速度较慢，使得部署变得困难。在本文中，我们开发了一种高效的算法，在保持模型质量的同时搜索快速模型。我们描述了一种新颖的方法，将Transformer架构分解成更小的组件，并提出了一种基于采样的单次架构搜索方法，以找到适合推理的最佳模型。与替代方案相比，模型搜索过程更加高效，仅对训练时间增加了少量开销。通过将我们的方法应用于BERT-base架构，我们在预训练的BERT上实现了10%到30%的速度提升，在Cloud TPU-v2上，相对于之前的最先进蒸馏BERT模型，我们实现了70%的速度提升，同时性能下降在可接受范围内。
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English: The electronic properties of hydrogenated graphenes are investigated with the
first-principles calculations. Geometric structures, energy bands, charge
distributions, and density of states (DOS) strongly depend on the different
configurations and concentrations of hydrogen adatoms. Among three types of
optimized periodical configurations, only in the zigzag systems the band gaps
can be remarkably modulated by H-concentrations. There exist middle-gap
semiconductors, narrow-gap semiconductors, and gapless systems. The band
structures exhibit the rich features, including the destruction or recovery of
the Dirac-cone structure, newly formed critical points, weakly dispersive
bands, and (C,H)-related partially flat bands. The orbital-projected DOS are
evidenced by the low-energy prominent peaks, delta-function-like peaks,
discontinuous shoulders, and logarithmically divergent peaks. The DOS and
spatial charge distributions clearly indicate that the critical bondings in C-C
and C-H is responsible for the diversified properties.
Chinese: 使用第一性原理计算研究了氢化石墨烯的电子性质。几何结构、能带、电荷分布和态密度（DOS）强烈依赖于氢吸附原子的不同配置和浓度。在三种优化的周期性配置中，只有锯齿状系统中能带间隙可以通过氢浓度显著调节。存在中隙半导体、窄隙半导体和无隙系统。能带结构表现出丰富的特征，包括Dirac锥结构的破坏或恢复、新形成的临界点、弱分散的能带以及与(C,H)相关的部分平坦能带。轨道投影态密度通过低能显著峰、类似δ函数的峰、不连续的肩部和对数发散的峰得到证实。态密度和空间电荷分布清楚地表明，C-C和C-H中的临界键合是导致多样化性质的原因。
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English: The 5G VINNI testbed infrastructure project provides 5G facilities for
pan-European services. Within the project, the UK site is one of the 5G-VINNI
facilities that targets developing a flexible and dynamic test environment
which can be adapted to meet requirements from H2020 funded projects as well as
external trials, to enable vertical industries to assess 5G networks in the
context of advanced digital use cases. In this paper, we present a full
overview of the 5G test infrastructure developed at the UK 5G VINNI facility,
including backhaul, edge, slicing, interworking and validation. This work
presents an operator's experience in setting up a testbed facility and in
engaging with different verticals conducting their research projects using the
5G facility, and the results and benefits to the industry. Furthermore, the
lessons learned from the design, installation, operation and experimentation
phases of the project are discussed.
Chinese: 5G VINNI测试床基础设施项目为全欧洲服务提供5G设施。在项目内部，英国站点是5G-VINNI设施之一，旨在开发一个灵活且动态的测试环境，该环境可以适应满足H2020资助项目以及外部试验的需求，以使垂直行业能够在高级数字用例的背景下评估5G网络。在本文中，我们展示了在英国5G VINNI设施开发的5G测试基础设施的全面概述，包括回程、边缘、切片、互操作性和验证。这项工作展示了运营商在建立测试床设施以及与不同垂直行业合作进行其研究项目使用5G设施的经验，以及这些结果和益处对行业的影响。此外，还讨论了项目在设计、安装、运营和实验阶段所吸取的教训。
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English: Numerous surveys have shown that Web users are concerned about the loss of
privacy associated with online tracking. Alarmingly, these surveys also reveal
that people are also unaware of the amount of data sharing that occurs between
ad exchanges, and thus underestimate the privacy risks associated with online
tracking.
In reality, the modern ad ecosystem is fueled by a flow of user data between
trackers and ad exchanges. Although recent work has shown that ad exchanges
routinely perform cookie matching with other exchanges, these studies are based
on brittle heuristics that cannot detect all forms of information sharing,
especially under adversarial conditions.
In this study, we develop a methodology that is able to detect client- and
server-side flows of information between arbitrary ad exchanges. Our key
insight is to leverage retargeted ads as a tool for identifying information
flows. Intuitively, our methodology works because it relies on the semantics of
how exchanges serve ads, rather than focusing on specific cookie matching
mechanisms. Using crawled data on 35,448 ad impressions, we show that our
methodology can successfully categorize four different kinds of information
sharing behavior between ad exchanges, including cases where existing heuristic
methods fail.
We conclude with a discussion of how our findings and methodologies can be
leveraged to give users more control over what kind of ads they see and how
their information is shared between ad exchanges.
Chinese: 众多调查表明，网络用户对与在线追踪相关的隐私损失表示担忧。令人惊讶的是，这些调查还揭示了人们对广告交易所之间发生的数据共享量并不了解，因此低估了与在线追踪相关的隐私风险。
实际上，现代广告生态系统是由追踪器和广告交易所之间用户数据的流动所驱动的。尽管最近的研究表明广告交易所通常会与其他交易所进行cookie匹配，但这些研究基于脆弱的启发式方法，无法检测所有形式的信息共享，尤其是在对抗性条件下。
在本研究中，我们开发了一种能够检测任意广告交易所之间客户端和服务器端信息流动的方法。我们的关键洞察是利用重定向广告作为识别信息流的工具。直观地说，我们的方法之所以有效，是因为它依赖于交易所如何提供服务广告的语义，而不是专注于特定的cookie匹配机制。使用35,448次广告印象的爬取数据，我们表明我们的方法可以成功地将广告交易所之间的四种不同类型的信息共享行为进行分类，包括现有启发式方法失效的情况。
我们最后讨论了如何利用我们的发现和方法，让用户对看到哪种广告以及他们的信息如何在广告交易所之间共享拥有更多控制权。
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English: Trajectory planning under uncertainty is an active research topic. Previous
works predict state and state estimation uncertainties along trajectories to
check for collision safety. They assume either stochastic or bounded sensing
uncertainties. However, GNSS pseudoranges are typically modeled to contain
stochastic uncertainties with additional biases in urban environments. Thus,
given bounds for the bias, the planner needs to account for both stochastic and
bounded sensing uncertainties. In our prior work we presented a reachability
analysis to predict state and state estimation uncertainties under stochastic
and bounded uncertainties. However, we ignored the correlation between these
uncertainties, leading to an imperfect approximation of the state uncertainty.
In this paper we improve our reachability analysis by predicting state
uncertainty as a function of independent quantities. We design a metric for the
predicted uncertainty to compare candidate trajectories during planning.
Finally, we validate the planner for GNSS-based urban navigation of fixed-wing
UAS.
Chinese: 不确定性下的轨迹规划是一个活跃的研究课题。先前的研究工作通过预测轨迹上的状态和状态估计不确定性来检查碰撞安全性，并假设存在随机或有界感知不确定性。然而，GNSS伪距通常被建模为包含城市环境中的随机不确定性和附加偏差。因此，给定偏差界限，规划者需要考虑随机和有界感知不确定性。在我们的先前工作中，我们提出了一种可达性分析，以预测随机和有界不确定性下的状态和状态估计不确定性。然而，我们忽略了这些不确定性之间的相关性，导致状态不确定性的近似不完善。在本文中，我们通过将状态不确定性预测为独立量的函数来改进我们的可达性分析。我们设计了一种预测不确定性的度量标准，用于在规划过程中比较候选轨迹。最后，我们验证了基于GNSS的城市固定翼UAS导航的规划器。
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English: In this study, we take a closer look at how Winograd schema challenges can be
used to evaluate common sense reasoning in LLMs. Specifically, we evaluate
generative models of different sizes on the popular WinoGrande benchmark. We
release WinoWhat, a new corpus, in which each instance of the WinoGrande
validation set is paraphrased. Additionally, we evaluate the performance on the
challenge across five common sense knowledge categories, giving more
fine-grained insights on what types of knowledge are more challenging for LLMs.
Surprisingly, all models perform significantly worse on WinoWhat, implying that
LLM reasoning capabilities are overestimated on WinoGrande. To verify whether
this is an effect of benchmark memorization, we match benchmark instances to
LLM trainingdata and create two test-suites. We observe that memorization has a
minimal effect on model performance on WinoGrande.
Chinese: 在这项研究中，我们更深入地探讨如何利用Winograd方案挑战来评估大型语言模型中的常识推理。具体来说，我们在流行的WinoGrande基准上评估了不同规模的生成模型。我们发布了一个新的语料库WinoWhat，其中WinoGrande验证集中的每个实例都被改写。此外，我们还评估了在五个常识知识类别上的挑战表现，为哪些类型的知识对大型语言模型更具挑战性提供了更细致的见解。令人惊讶的是，所有模型在WinoWhat上的表现都显著更差，这意味着在WinoGrande上对大型语言模型的推理能力估计过高。为了验证这是否是基准记忆的影响，我们将基准实例与大型语言模型的训练数据相匹配，并创建了两个测试套件。我们观察到，记忆对WinoGrande上的模型性能的影响最小。
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English: We present the near light cone Hamiltonian $H$ in lattice QCD depending on
the parameter $\eta$, which gives the distance to the light cone. Since the
vacuum has zero momentum we can derive an effective Hamiltonian $H_{eff}$ from
$H$ which is only quadratic in the momenta and therefore solvable by standard
methods. An approximate ground state wave functional is determined
variationally in the limit $\eta \to 0$.
Chinese: 我们提出了近光锥哈密顿量 $H$，它在晶格量子色动力学中依赖于参数 $\eta$，该参数给出了光锥的距离。由于真空具有零动量，我们可以从 $H$ 中推导出一个有效哈密顿量 $H_{eff}$，它在动量中仅是二次的，因此可以通过标准方法求解。在 $\eta \to 0$ 的极限下，通过变分方法确定了一个近似的基态波泛函。
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English: We prove the occurrence of Anderson localisation for a system of infinitely
many particles interacting with a short range potential, within the ground
state Hartree-Fock approximation. We assume that the particles hop on a
discrete lattice and that they are submitted to an external periodic potential
which creates a gap in the non-interacting one particle Hamiltonian. We also
assume that the interaction is weak enough to preserve a gap. We prove that the
mean-field operator has exponentially localised eigenvectors, either on its
whole spectrum or at the edges of its bands, depending on the strength of the
disorder.
Chinese: 我们在无限多粒子与短程势相互作用的系统中，在哈特里-福克近似下证明了安德森局域化的发生。我们假设粒子在离散格点上运动，并受到一个产生非相互作用单粒子哈密顿量能隙的外周期势的作用。我们还假设相互作用足够弱以保持能隙。我们证明了平均场算子的本征矢量在指数局域，这取决于无序强度，要么在整个谱上，要么在能带边缘。
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English: Quantum criticality nearby a certain magnetic phase transition beneath the
superconducting dome of $\mathrm{Ba_{1-x}Na_xFe_2As_2}$ is attentively studied
by virtue of a phenomenological theory in conjunction with renormalization
group approach. We report that ordering competition between magnetic and
superconducting fluctuations is capable of coaxing incommensurate (IC) magnetic
states to experience distinct fates depending upon their spin configurations.
The $C_2$-symmetry IC magnetic stripe with perpendicular magnetic helix
dominates over other $C_2$-symmetry magnetic competitors and hints at a
potential candidate for the unknown $C_2$-symmetry magnetic state. Amongst
$C_4$-symmetry IC magnetic phases, IC charge spin density wave is substantiated
to be superior, shedding light on the significant intertwining of charge and
spin degrees of freedom. Meanwhile, ferocious fluctuations render a sharp fall
of superfluid density alongside dip of critical temperature as well as
intriguing behavior of London penetration depth.
Chinese: 在 $\mathrm{Ba_{1-x}Na_xFe_2As_2}$ 的超导穹顶下方，靠近某一磁性相变的量子临界性，通过结合现象学理论和重整化群方法进行了深入研究。我们报告称，磁性和超导涨落之间的序竞争能够使非简并（IC）磁性状态根据其自旋配置经历不同的命运。具有垂直磁性螺旋的 $C_2$-对称 IC 磁条纹主导着其他 $C_2$-对称磁性竞争者，并暗示了未知 $C_2$-对称磁性状态的潜在候选者。在 $C_4$-对称 IC 磁相中，非简并电荷自旋密度波被证实是优越的，揭示了电荷和自旋自由度的显著交织。同时，剧烈的涨落导致超流密度急剧下降，伴随临界温度的降低以及伦敦穿透深度的奇特行为。
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English: Aims. We introduce the TELAMON program which is using the Effelsberg 100-m
telescope to monitor the radio spectra of active galactic nuclei (AGN) under
scrutiny in astroparticle physics, specifically TeV blazars and candidate
neutrino-associated AGN. Here, we present and characterize our main sample of
TeV-detected blazars.
Methods. We analyze the data sample from the first ~2.5 years of observations
between August 2020 and February 2023 in the range from 14 GHz to 45 GHz.
During this pilot phase, we have observed all 59 TeV-detected blazars in the
Northern Hemisphere (i.e., Dec. >0{\deg}) known at the time of observation. We
discuss the basic data reduction and calibration procedures used for all
TELAMON data and introduce a sub-band averaging method used to calculate
average light curves for the sources in our sample.
Results. The TeV-selected sources in our sample exhibit a median flux density
of 0.12 Jy at 20 mm, 0.20 Jy at 14 mm and 0.60 Jy at 7 mm. The spectrum for
most of the sources is consistent with a flat radio spectrum and we find a
median spectral index ($S(\nu)\propto\nu^\alpha$) of $\alpha=-0.11$. Our
results on flux density and spectral index are consistent with previous studies
of TeV-selected blazars. Compared to the GeV-selected F-GAMMA sample, TELAMON
sources are significantly fainter in the radio band. This is consistent with
the double-humped spectrum of blazars being shifted towards higher frequencies
for TeV-emitters (in particular for high-synchrotron peaked BL Lac type
objects), which results in a lower radio flux density. The spectral index
distribution of our TeV-selected blazar sample is not significantly different
from the GeV-selected F-GAMMA sample. Moreover, we present a strategy to track
the light curve evolution of sources in our sample for future variability and
correlation analysis.
Chinese: 目标。我们介绍了TELAMON项目，该项目利用Effelsberg 100米望远镜监测天体粒子物理学中备受关注的活跃星系核（AGN）的无线电光谱，特别是TeV喷流星系和候选中微子相关AGN。在这里，我们展示并描述了我们主要样本中的TeV探测到的喷流星系。
方法。我们分析了从2020年8月至2023年2月的前约2.5年的观测数据，观测范围在14 GHz至45 GHz之间。在这个试点阶段，我们观测了当时已知的所有59个TeV探测到的北半球（即赤纬>0°）喷流星系。我们讨论了用于所有TELAMON数据的初步数据降级和校准程序，并介绍了一种用于计算样本中源的平均光变曲线的子带平均方法。
结果。我们样本中的TeV选择源在20毫米处的中值通量密度为0.12 Jy，在14毫米处为0.20 Jy，在7毫米处为0.60 Jy。大多数源的光谱与平坦的无线电光谱一致，我们发现中值光谱指数（S(ν)∝ν^α）为α=-0.11。我们关于通量密度和光谱指数的结果与先前关于TeV选择喷流星系的研究一致。与GeV选择的F-GAMMA样本相比，TELAMON源在无线电波段中明显更暗。这与喷流星系的双峰光谱在TeV发射源（特别是高同步辐射峰BL Lac类型对象）中向更高频率移动的事实一致，这导致无线电通量密度较低。我们TeV选择喷流星系样本的光谱指数分布与GeV选择的F-GAMMA样本没有显著差异。此外，我们提出了一种策略，用于跟踪样本中源的光变曲线演化，以进行未来的可变性和相关性分析。
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English: The observed delay of GRB 170817A relative to GW170817 carries significant
information about gamma-ray burst (GRB) physics and is subject to intense
debate. In this letter, we put forward an approach to discuss the major source
of this time delay. First of all, we use the structured jet model to fit the
X-ray/optical/radio afterglows of GRB 170817A together with superluminal motion
measured by the Very Long Baseline Interferometry. Our structured jet is
modelled with angle-dependent energy and baryon loading. It is found that our
model can well fit the afterglows of GRB 170817A. After that, the baryon
loading in the jet is inferred based on our fitting results. By comparing the
baryon loading to the mass outflow in different stages, we infer that the time
lag of the jet launch relative to the merger is less than hundreds or tens of
milliseconds. It suggests that the time delay of GRB 170817A relative to
GW170817 is defined mostly by the spreading time of the jet propagating to its
dissipation radius.
Chinese: GRB 170817A相对于GW170817的观测延迟携带着关于伽马射线暴（GRB）物理的重要信息，并引发了激烈的争论。在这封信中，我们提出了一种讨论这种时间延迟主要来源的方法。首先，我们利用结构化喷流模型拟合GRB 170817A的X射线/光学/射电余辉，并结合通过甚长基线干涉测量得到的超光速运动。我们的结构化喷流模型以角度相关的能量和重子加载为特征。我们发现，我们的模型可以很好地拟合GRB 170817A的余辉。随后，根据我们的拟合结果，推断出喷流中的重子加载。通过将重子加载与不同阶段的质量流出量进行比较，我们推断出喷流发射相对于合并的时间滞后少于数百或数十毫秒。这表明，GRB 170817A相对于GW170817的时间延迟主要由喷流传播到其耗散半径的扩散时间决定。
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English: In today's digital age, information systems (IS) are indispensable tools for
organizations of all sizes. The quality of these systems, encompassing system,
information, and service dimensions, significantly impacts organizational
performance. This study investigates the intricate relationships between these
three quality dimensions and their collective influence on key performance
indicators such as customer satisfaction and operational efficiency. By
conducting a comparative analysis of various quality metrics, we aim to
identify the most effective indicators for assessing IS quality. Our research
contributes to the field by providing actionable insights for researchers or
practitioners to develop the implementation, evaluation and design of
information systems. Also, a quantitative study employing a structured
questionnaire survey was conducted to achieve primary data from respondents
across various sectors. Statistical analysis, including Cronbach's Alpha
(0.953) and factor analysis (KMO = 0.965, Bartlett's Test p < 0.000), revealed
strong interdependencies among System Quality (SQ), Information Quality (IQ),
and Service Quality (SerQ). The results demonstrate that high SQ leads to
improved IQ, which in turn contributes to enhanced SerQ and user satisfaction.
While all three qualities are crucial, SerQ emerges as the most relevant
indicator of overall system performance due to its broader representation of
quality dimensions
Chinese: 在当今数字时代，信息系统（IS）已成为所有规模组织不可或缺的工具。这些系统的质量，涵盖系统、信息和服务的维度，对组织绩效有显著影响。本研究探讨了这三个质量维度之间的复杂关系及其对关键绩效指标（如客户满意度和运营效率）的集体影响。通过比较分析各种质量指标，我们旨在识别评估信息系统质量的最有效指标。我们的研究通过为研究人员或实践者提供可操作的见解，为信息系统实施、评估和设计领域做出贡献。此外，还进行了一项采用结构化问卷调查的定量研究，以从不同行业的受访者那里获取初步数据。统计分析，包括Cronbach's Alpha（0.953）和因子分析（KMO = 0.965，Bartlett检验p < 0.000），揭示了系统质量（SQ）、信息质量（IQ）和服务质量（SerQ）之间的强相互依赖性。结果表明，高SQ能提升IQ，进而有助于增强SerQ和用户满意度。虽然这三个质量都很重要，但由于其更广泛地代表了质量维度，SerQ成为衡量整体系统性能的最相关指标。
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English: We investigate the discovery potential of Kaluza-Klein gluons as a dijet
resonance at hadron colliders with different center-of-mass energies, from 14
TeV to 33 TeV to 100 TeV. We also present the current bounds from dijet
searches at UA2, Tevatron, and LHC.
Chinese: 我们研究了卡鲁扎-克莱因胶子作为双喷注共振在不同质心能量的强子对撞机（从14 TeV到33 TeV到100 TeV）上的发现潜力。我们还呈现了UA2、Tevatron和LHC双喷注搜索的当前限制。
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English: Given a dataset of individuals each described by a covariate vector, a
treatment, and an observed outcome on the treatment, the goal of the individual
treatment effect (ITE) estimation task is to predict outcome changes resulting
from a change in treatment. A fundamental challenge is that in the
observational data, a covariate's outcome is observed only under one treatment,
whereas we need to infer the difference in outcomes under two different
treatments. Several existing approaches address this issue through training
with inferred pseudo-outcomes, but their success relies on the quality of these
pseudo-outcomes. We propose PairNet, a novel ITE estimation training strategy
that minimizes losses over pairs of examples based on their factual observed
outcomes. Theoretical analysis for binary treatments reveals that PairNet is a
consistent estimator of ITE risk, and achieves smaller generalization error
than baseline models. Empirical comparison with thirteen existing methods
across eight benchmarks, covering both discrete and continuous treatments,
shows that PairNet achieves significantly lower ITE error compared to the
baselines. Also, it is model-agnostic and easy to implement.
Chinese: 给定一个由协变量向量、治疗方案和观察到的治疗效果描述的个体数据集，个体治疗方案（ITE）估计任务的目标是预测治疗方案变化引起的治疗效果变化。一个基本挑战是，在观察数据中，协变量的结果仅在一种治疗方案下被观察到，而我们需要推断两种不同治疗方案下的结果差异。几种现有的方法通过使用推断的伪结果进行训练来解决此问题，但它们的成功依赖于这些伪结果的质量。我们提出了PairNet，这是一种新颖的ITE估计训练策略，它通过基于事实观察结果对成对示例的最小化损失来训练。对于二元治疗方案的理论分析表明，PairNet是ITE风险的稳健估计器，并且比基线模型实现了更小的泛化误差。在八个基准上与十三种现有方法的实证比较，涵盖了离散和连续治疗方案，表明与基线相比，PairNet实现了显著更低的ITE误差。此外，它对模型无偏见且易于实现。
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English: We predict the thermal counterpart of the anomalous Josephson effect in
superconductor/ferromagnet/superconductor junctions with non-coplanar magnetic
texture. The heat current through the junction is shown to have the
phase-sensitive interference component proportional to $\cos(\theta -
\theta_0)$, where $\theta$ is the Josephson phase difference and $\theta_0$ is
the texture-dependent phase shift. In the generic tri-layer magnetic structure
with the spin-filtering tunnel barrier $\theta_0$ is determined by the spin
chirality of magnetic configuration and can be considered as the direct
manifestation of the energy transport with participation of spin-triplet Cooper
pairs. In case of the ideal spin filter the phase shift is shown to be robust
against spin relaxation caused by the spin-orbital scattering. Possible
applications of the coupling between heat flow and magnetic precession are
discussed.
Chinese: 我们预测了超导体/铁磁体/超导体结中非共面磁纹理的异常约瑟夫森效应的热对应物。通过结的热电流显示出具有相敏感的干涉分量，该分量与 $\cos(\theta - \theta_0)$ 成正比，其中 $\theta$ 是约瑟夫森相差，$\theta_0$ 是纹理相关的相移。在具有自旋过滤隧道势垒的通用三层磁结构中，$\theta_0$ 由磁配置的自旋手征性决定，可以被视为涉及自旋三重态库珀对的能量传输的直接表现。在理想的自旋滤波器情况下，相移显示出对由自旋轨道散射引起的自旋弛豫具有鲁棒性。讨论了热流与磁进动之间耦合的可能应用。
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English: We report on efficient generation of second harmonic laser and single-mode
vacuum squeezed light of 795 nm with periodically poled KTiOPO4 (PPKTP)
crystals. We achieved 111 mW of ultra-violet (UV) light at 397.5 nm from 191 mW
of fundamental light with a PPKTP crystal in a doubling cavity, corresponding
to a conversion efficiency of 58.1%. Using the UV light to pump an optical
parametric oscillator with a PPKTP crystal, we realized -5.6 dB of a maximum
squeezing. We analyzed the pump power dependence of the squeezing level and
concluded that the UV light induced losses limit the improvement of the
squeezing level. The generated squeezed light has huge potential application in
quantum memory and ultra-precise measurement.
Chinese: 我们报告了使用周期性极化的 KTiOPO4 (PPKTP) 晶体高效产生 795 nm 的二次谐波激光和单模真空压缩光。我们通过一个双倍腔中的 PPKTP 晶体，从 191 mW 的基光中获得了 111 mW 的紫外线 (UV) 光，波长为 397.5 nm，转换效率为 58.1%。利用 UV 光泵浦一个包含 PPKTP 晶体的光学参量振荡器，我们实现了 -5.6 dB 的最大压缩。我们分析了泵浦功率对压缩水平的影响，并得出结论，UV 光引起的损耗限制了压缩水平的提升。生成的压缩光在量子存储和超精密测量中具有巨大的应用潜力。
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English: We have detected the synchronous enhancement of Ca II H & K emission with the
short-period planetary orbit in HD 179949. High-resolution spectra taken on
three observing runs extending more than a year show the enhancement coincides
with phi ~ 0 (the sub-planetary point) of the 3.093-day orbit with the effect
persisting for more than 100 orbits. The synchronous enhancement is consistent
with planet-induced chromospheric heating by magnetic rather than tidal
interaction. Something which can only be confirmed by further observations.
Independent observations are needed to determine whether the stellar rotation
is sychronous with the planet's orbit. Of the five 51 Peg-type systems
monitored, HD 179949 shows the greatest chromospheric H & K activity. Three
others show significant nightly variations but the lack of any phase coherence
prevents us saying whether the activity is induced by the planet. Our two
standards, tau Ceti and the Sun, show no such nightly variations.
Chinese: 我们在HD 179949中检测到钙II H & K发射线与短周期行星轨道的同步增强。在持续超过一年的三次观测中获取的高分辨率光谱显示，这种增强与3.093天轨道的φ~0（子星点）相位一致，且持续超过100个轨道周期。这种同步增强与行星通过磁力而非潮汐相互作用引起的色球层加热现象一致，这一点只能通过进一步观测来确认。需要独立观测来判断恒星自转是否与行星轨道同步。在监测的五个51 Pegasi型系统中，HD 179949显示出最强的色球层H & K活动。其他三个系统存在显著的日变化，但由于缺乏相位一致性，我们无法确定这种活动是否由行星引起。我们的两个参考标准——半人马座τ星和太阳——则没有这种日变化。
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English: Damping is defined through various terms such as energy loss per cycle (for
cyclic tests), logarithmic decrement (for vibration tests), complex modulus,
rise-time or spectrum ratio (for wave propagation analysis), etc. For numerical
modeling purposes, another type of damping is frequently used : it is called
Rayleigh damping. It is a very convenient way of accounting for damping in
numerical models, although the physical or rheological meaning of this approach
is not clear. A rheological model is proposed to be related to classical
Rayleigh damping : it is a generalized Maxwell model with three parameters. For
moderate damping (<25%), this model perfectly coincide with Rayleigh damping
approach since internal friction has the same expression in both cases and
dispersive phenomena are negligible. This is illustrated by finite element
(Rayleigh damping) and analytical (generalized Maxwell model) results in a
simple one-dimensional case.
Chinese: 阻尼可通过多种术语定义，例如每周期能量损失（用于循环试验）、对数衰减（用于振动试验）、复模量、上升时间或频谱比（用于波传播分析）等。在数值建模中，另一种类型的阻尼被频繁使用，称为雷利阻尼。这是一种在数值模型中考虑阻尼的非常便捷的方法，尽管这种方法的物理或流变学意义并不明确。提出了一种流变模型与经典雷利阻尼相关联：它是一个具有三个参数的广义麦克斯韦模型。对于中等阻尼（<25%），该模型与雷利阻尼方法完全一致，因为两种情况下内摩擦的表达式相同，且色散现象可忽略不计。这通过一个简单一维情况下的有限元（雷利阻尼）与解析（广义麦克斯韦模型）结果得到说明。
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English: In the frame of a systematical study of light ion induced nuclear reactions
on platinum, activation cross sections for deuteron induced reactions were
investigated. Excitation functions were measured in the 20.8 - 49.2 MeV energy
range for the natPt(d,xn)191,192,193,194,195,196m2,196g,198g,199Au,
natPt(d,x)188,189,191,195m,197m,197gPt and natPt(d,x)189,190,192,194m2Ir
reactions by using the stacked foil irradiation technique. The experimental
results are compared with previous results from the literature and with the
theoretical predictions in the TENDL-2014 and TENDL-2015 libraries. The
applicability of the produced radio-tracers for wear measurements has been
presented.
Chinese: 在系统研究光离子诱导铂核反应的框架下，研究了氘诱导反应的活化截面。通过堆叠箔照射技术，在20.8 - 49.2 MeV能量范围内测量了natPt(d,xn)191,192,193,194,195,196m2,196g,198g,199Au、natPt(d,x)188,189,191,195m,197m,197gPt和natPt(d,x)189,190,192,194m2Ir反应的激发函数。实验结果与文献中的先前结果以及TENDL-2014和TENDL-2015库中的理论预测进行了比较。已提出所生产的放射性示踪剂在磨损测量中的应用。
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English: We provide a class of commutative Noetherian domains $R$ of dimension $d$
such that every finitely generated projective $R$-module $P$ of rank $d$ splits
off a free summand of rank one. On this class, we also show that $P$ is
cancellative. At the end we give some applications to the number of generators
of a module over the Rees algebras.
Chinese: 我们提供了一类维数为$d$的交换诺特利安域$R$，使得每个有限生成的秩为$d$的投射$R$-模$P$都包含一个秩为1的自由和项。在这类上，我们同样证明了$P$是可消的。最后，我们给出了一些关于Rees代数上的模的生成数的应用的例子。
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English: Resolving a conjecture of Bollob\'{a}s and Erd\H{o}s, Gy\'{a}rf\'{a}s proved
that every graph $G$ of chromatic number $k+1\geq 3$ contains cycles of
$\lfloor\frac{k}{2}\rfloor$ distinct odd lengths. We strengthen this prominent
result by showing that such $G$ contains cycles of $\lfloor\frac{k}{2}\rfloor$
consecutive odd lengths. Along the way, combining extremal and structural
tools, we prove a stronger statement that every graph of chromatic number
$k+1\geq 7$ contains $k$ cycles of consecutive lengths, except that some block
is $K_{k+1}$. As corollaries, this confirms a conjecture of Verstra\"ete and
answers a question of Moore and West.
Chinese: 解决波尔洛贝斯和爱多斯的一个猜想，吉亚尔法斯证明了色数k+1≥3的每个图G都包含\lfloor \frac{k}{2} \rfloor个长度互不相同的奇数长度回路。我们通过表明这样的G包含\lfloor \frac{k}{2} \rfloor个连续奇数长度回路，加强了这一重要结果。在此过程中，结合极值理论和结构工具，我们证明了更强的命题：色数k+1≥7的每个图都包含k个连续长度回路，除了某些块是K_{k+1}。作为推论，这证实了Verstraete的猜想，并回答了Moore和West的问题。
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English: Learning sentence vectors from an unlabeled corpus has attracted attention
because such vectors can represent sentences in a lower dimensional and
continuous space. Simple heuristics using pre-trained word vectors are widely
applied to machine learning tasks. However, they are not well understood from a
theoretical perspective. We analyze learning sentence vectors from a transfer
learning perspective by using a PAC-Bayes bound that enables us to understand
existing heuristics. We show that simple heuristics such as averaging and
inverse document frequency weighted averaging are derived by our formulation.
Moreover, we propose novel sentence vector learning algorithms on the basis of
our PAC-Bayes analysis.
Chinese: 从未标记语料库中学习句子向量引起了人们的关注，因为这样的向量可以在低维和连续的空间中表示句子。使用预训练的词向量进行简单启发式方法在机器学习任务中得到了广泛应用。然而，从理论角度来看，这些方法并不被很好地理解。我们通过使用PAC-Bayes界限来分析从迁移学习角度学习句子向量，这使我们能够理解现有的启发式方法。我们表明，平均和逆文档频率加权平均等简单启发式方法是通过我们的公式推导出来的。此外，我们基于我们的PAC-Bayes分析提出了新颖的句子向量学习算法。
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English: We calculate how primordial anisotropies in the background space-time affect
the evolution of cosmological perturbations for bouncing alternatives to
inflation, like ekpyrosis and the matter bounce scenario. We find that the
leading order effect of anisotropies in the contracting phase of the universe
is to induce anisotropies in the cosmic microwave background with a very
concrete form: a scale-invariant quadrupolar angular distribution. Sub-leading
effects are the generation of higher-order moments in the angular distribution,
as well as cross-correlations between scalar and tensor modes. We also find
that observational constraints from the cosmic microwave background on the
quadrupole moment provide strong bounds on allowed anisotropies for bouncing
alternatives to inflation that are significantly more constraining than the
bounds previously obtained using scaling arguments based on the conjectured
Belinski-Khalatnikov-Lifshitz instability.
Chinese: 我们计算背景时空中的原初各向异性如何影响宇宙学扰动的演化，对于像大爆炸和物质反弹情景这样的宇宙反弹替代方案。我们发现，宇宙收缩阶段各向异性的主导效应是诱导出具有非常具体形式的宇宙微波背景中的各向异性：一个尺度不变的偶极角分布。次主导效应是角分布中更高阶矩的产生，以及标量模式和标量模式之间的交叉相关性。我们还发现，来自宇宙微波背景对偶极矩的观测约束为宇宙反弹替代方案提供了强约束，这些约束比基于假设的Belinski-Khalatnikov-Lifshitz不稳定性建立的尺度论证所获得的约束要严格得多。
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English: We experimentally investigated the characteristics of two-photon transmission
resonances in Rb vapor cells with different amount of buffer gas under the
conditions of steady-state coherent population trapping (CPT) and pulsed
Raman-Ramsey (RR-) CPT interrogation scheme. We particularly focused on the
influence of the Rb atoms diffusing in and out of the laser beam. We showed
that this effect modifies the shape of both CPT and Raman-Ramsey resonances, as
well as their projected performance for CPT clock applications. In particular
we found that at moderate buffer gas pressures RR-CPT did not improved the
projected atomic clock stability compare to the regular steady-state CPT
resonance.
Chinese: 我们在稳态相干布居俘获（CPT）和脉冲拉曼-拉姆齐（RR-）CPT探测方案下，实验研究了装有不同缓冲气体量的Rb蒸汽池中双光子传输谐振子的特性。我们特别关注了Rb原子在激光束中扩散进出的影响。我们表明，这种效应会改变CPT和拉曼-拉姆齐谐振子的形状，以及它们在CPT钟应用中的预期性能。特别地，我们发现在中等缓冲气体压力下，RR-CPT与常规稳态CPT谐振子相比，并未提高预期的原子钟稳定性。
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English: Recent advances in transformers have enabled Table Question Answering (Table
QA) systems to achieve high accuracy and SOTA results on open domain datasets
like WikiTableQuestions and WikiSQL. Such transformers are frequently
pre-trained on open-domain content such as Wikipedia, where they effectively
encode questions and corresponding tables from Wikipedia as seen in Table QA
dataset. However, web tables in Wikipedia are notably flat in their layout,
with the first row as the sole column header. The layout lends to a relational
view of tables where each row is a tuple. Whereas, tables in domain-specific
business or scientific documents often have a much more complex layout,
including hierarchical row and column headers, in addition to having
specialized vocabulary terms from that domain.
To address this problem, we introduce the domain-specific Table QA dataset
AIT-QA (Airline Industry Table QA). The dataset consists of 515 questions
authored by human annotators on 116 tables extracted from public U.S. SEC
filings (publicly available at: https://www.sec.gov/edgar.shtml) of major
airline companies for the fiscal years 2017-2019. We also provide annotations
pertaining to the nature of questions, marking those that require hierarchical
headers, domain-specific terminology, and paraphrased forms. Our zero-shot
baseline evaluation of three transformer-based SOTA Table QA methods - TaPAS
(end-to-end), TaBERT (semantic parsing-based), and RCI (row-column
encoding-based) - clearly exposes the limitation of these methods in this
practical setting, with the best accuracy at just 51.8\% (RCI). We also present
pragmatic table preprocessing steps used to pivot and project these complex
tables into a layout suitable for the SOTA Table QA models.
Chinese: 近年来，在变压器领域的最新进展使得表格问答（Table QA）系统在开放域数据集如WikiTableQuestions和WikiSQL上实现了高精度和SOTA（最先进的技术）结果。这类变压器通常在开放域内容如维基百科上进行预训练，其中它们有效地编码了维基百科中的问题和相应的表格，正如在表格问答数据集中所见。然而，维基百科中的网络表格在布局上明显很扁平，第一行作为唯一的列标题。这种布局倾向于将表格视为关系视图，其中每一行都是一个元组。而特定领域的商业或科学文档中的表格通常具有更复杂的布局，包括分层行和列标题，此外还包含该领域的专业词汇术语。
为了解决这个问题，我们引入了特定领域的表格问答数据集AIT-QA（航空业表格问答）。该数据集由人类标注者创作的515个问题组成，这些问题基于从2017-2019财年美国主要航空公司公开的U.S. SEC文件（公开可访问于：https://www.sec.gov/edgar.shtml）中提取的116个表格。我们还提供了与问题性质相关的标注，标记了需要分层标题、特定领域术语和释义形式的问题。我们对三种基于变压器的SOTA表格问答方法——TaPAS（端到端）、TaBERT（基于语义解析）和RCI（基于行-列编码）——进行了零样本基线评估，这些方法在此实际设置中的局限性明显，最佳准确率仅为51.8%（RCI）。我们还展示了用于将复杂表格旋转和投影到适合SOTA表格问答模型的布局的实用表格预处理步骤。
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English: Foundation models (FM), such as large language models (LLMs), which are
large-scale machine learning (ML) models, have demonstrated remarkable
adaptability in various downstream software engineering (SE) tasks, such as
code completion, code understanding, and software development. As a result, FM
leaderboards have become essential tools for SE teams to compare and select the
best third-party FMs for their specific products and purposes. However, the
lack of standardized guidelines for FM evaluation and comparison threatens the
transparency of FM leaderboards and limits stakeholders' ability to perform
effective FM selection. As a first step towards addressing this challenge, our
research focuses on understanding how these FM leaderboards operate in
real-world scenarios ("leaderboard operations") and identifying potential
pitfalls and areas for improvement ("leaderboard smells"). In this regard, we
collect up to 1,045 FM leaderboards from five different sources: GitHub,
Hugging Face Spaces, Papers With Code, spreadsheet and independent platform, to
examine their documentation and engage in direct communication with leaderboard
operators to understand their workflows. Through card sorting and negotiated
agreement, we identify five distinct workflow patterns and develop a domain
model that captures the key components and their interactions within these
workflows. We then identify eight unique types of leaderboard smells in LBOps.
By mitigating these smells, SE teams can improve transparency, accountability,
and collaboration in current LBOps practices, fostering a more robust and
responsible ecosystem for FM comparison and selection.
Chinese: 基础模型（FM），例如大型语言模型（LLMs），这些是大规模机器学习（ML）模型，已经在各种下游软件工程（SE）任务中展现了卓越的适应性，例如代码补全、代码理解和软件开发。因此，FM排行榜已成为SE团队比较和选择最适合其特定产品和目的的第三方FM的重要工具。然而，缺乏对FM评估和比较的标准化指南，威胁到FM排行榜的透明度，并限制了利益相关者进行有效FM选择的能力。为了应对这一挑战的第一步，我们的研究专注于了解这些FM排行榜在现实场景中的运作方式（“排行榜运作”）以及识别潜在的陷阱和改进领域（“排行榜异味”）。在这方面，我们从五个不同的来源收集了多达1,045个FM排行榜：GitHub、Hugging Face Spaces、Papers With Code、电子表格和独立平台，以检查它们的文档并与排行榜操作员进行直接沟通，以了解他们的工作流程。通过卡片分类和协商一致，我们确定了五种不同的工作流程模式，并开发了一个领域模型，该模型捕捉了这些工作流程中的关键组件及其交互。然后，我们在LBOps中识别了八种独特的排行榜异味类型。通过减轻这些异味，SE团队可以提高当前LBOps实践中的透明度、责任感和协作性，促进更稳健、更负责任的FM比较和选择生态系统。
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English: In order to model an efficient learning paradigm, iterative learning
algorithms access data one by one, updating the current hypothesis without
regress to past data. Past research on iterative learning analyzed for example
many important additional requirements and their impact on iterative learners.
In this paper, our results are twofold. First, we analyze the relative learning
power of various settings of iterative learning, including learning from text
and from informant, as well as various further restrictions, for example we
show that strongly non-U-shaped learning is restrictive for iterative learning
from informant. Second, we investigate the learnability of the concept class of
half-spaces and provide a constructive iterative algorithm to learn the set of
half-spaces from informant.
Chinese: 为了构建一个高效的学习范式，迭代学习算法逐个访问数据，更新当前假设而不回归到过去的数据。过去关于迭代学习的研究分析了例如许多重要的附加要求及其对迭代学习者的 影响。在本文中，我们的结果有两方面。首先，我们分析了迭代学习各种设置的相对学习能力，包括从文本和从信息提供者那里学习，以及各种进一步的限制，例如我们表明，强烈的非U型学习对从信息提供者那里进行迭代学习是限制性的。其次，我们研究了半空间概念类可学习性，并提供了一个构造性的迭代算法来从信息提供者那里学习半空间集合。
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English: The iterative rational Krylov algorithm (IRKA) is a commonly used fixed-point
iteration developed to minimize the $\mathcal{H}_2$ model order reduction
error. In this work, IRKA is recast as a Riemannian gradient descent method
with a fixed step size over the manifold of rational functions having fixed
degree. This interpretation motivates the development of a Riemannian gradient
descent method utilizing as a natural extension variable step size and line
search. Comparisons made between IRKA and this extension on a few examples
demonstrate significant benefits.
Chinese: 迭代有理Krylov算法（IRKA）是一种常用的固定点迭代，旨在最小化模型阶次降低的$\mathcal{H}_2$误差。在本工作中，IRKA被重新定义为在固定多项式度数的有理函数流形上使用固定步长的黎曼梯度下降方法。这种解释激发了利用自然扩展的步长大小和线搜索开发黎曼梯度下降方法的发展。在几个例子上对IRKA与这个扩展进行的比较显示了显著的好处。
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English: In this work, we study the robustness of a CNN+RNN based image captioning
system being subjected to adversarial noises. We propose to fool an image
captioning system to generate some targeted partial captions for an image
polluted by adversarial noises, even the targeted captions are totally
irrelevant to the image content. A partial caption indicates that the words at
some locations in this caption are observed, while words at other locations are
not restricted.It is the first work to study exact adversarial attacks of
targeted partial captions. Due to the sequential dependencies among words in a
caption, we formulate the generation of adversarial noises for targeted partial
captions as a structured output learning problem with latent variables. Both
the generalized expectation maximization algorithm and structural SVMs with
latent variables are then adopted to optimize the problem. The proposed methods
generate very successful at-tacks to three popular CNN+RNN based image
captioning models. Furthermore, the proposed attack methods are used to
understand the inner mechanism of image captioning systems, providing the
guidance to further improve automatic image captioning systems towards human
captioning.
Chinese: 在这项工作中，我们研究了受到对抗性噪声影响的CNN+RNN基于图像描述系统鲁棒性。我们提出了一种欺骗图像描述系统的方法，使其为受对抗性噪声污染的图像生成一些目标部分描述，即使这些目标描述与图像内容完全不相关。部分描述表示在这个描述中某些位置的单词被观察到，而其他位置的单词则不受限制。这是第一个研究目标部分描述精确对抗性攻击的工作。由于描述中单词之间的序列依赖性，我们将针对部分描述的对抗性噪声生成问题表述为一个具有潜在变量的结构化输出学习问题。然后采用广义期望最大化算法和具有潜在变量的结构化支持向量机来优化这个问题。提出的方法对三种流行的CNN+RNN基于图像描述模型产生了非常成功的攻击。此外，提出的攻击方法被用来理解图像描述系统的内部机制，为进一步提高自动图像描述系统向人类描述靠拢提供指导。
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English: We develop several aspects of the infinite-dimensional Weak KAM theory using
a random variables' approach. We prove that the infinite-dimensional cell
problem admits a viscosity solution that is a fixed point of the Lax-Oleinik
semigroup. Furthermore, we show the existence of invariant minimizing measures
and calibrated curves defined on R.
Chinese: 我们使用随机变量的方法，发展了无限维弱KAM理论的几个方面。我们证明了无限维胞腔问题存在一个粘性解，它是Lax-Oleinik半群的一个不动点。此外，我们还展示了在R上存在不变的最小化测度和校准曲线。
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English: Content alignment in news media was an observable information effect of
Covid-19's initial phase. During the first half of 2020, legacy news media
became "corona news" following national outbreak and crises management
patterns. While news media are neither unbiased nor infallible as sources of
events, they do provide a window into socio-cultural responses to events. In
this paper, we use legacy print media to empirically derive the principle News
Information Decoupling (NID) that functions as an information signature of
culturally significant catastrophic event. Formally, NID can provide input to
change detection algorithms and points to several unsolved research problems in
the intersection of information theory and media studies.
Chinese: 新闻媒体在COVID-19初期阶段的内容对齐是一种可观察的信息效应。在2020年上半年，传统新闻媒体随着国家疫情爆发和危机管理模式的形成而转变为“冠状病毒新闻”。尽管新闻媒体作为事件来源既不客观也不完美，但它们确实为事件的社会文化反应提供了一个窗口。在本文中，我们使用传统印刷媒体来实证推导出作为文化重要灾难事件信息特征的“新闻信息解耦”（NID）原则。正式来说，NID可以为变化检测算法提供输入，并指向信息理论与媒体研究交叉领域中的几个未解决的问题。
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English: Evolving graphs arise in problems where interrelations between data change
over time. We present a breadth first search (BFS) algorithm for evolving
graphs that computes the most direct influences between nodes at two different
times. Using simple examples, we show that naive unfoldings of adjacency
matrices miscount the number of temporal paths. By mapping an evolving graph to
an adjacency matrix of an equivalent static graph, we prove that our
generalization of the BFS algorithm correctly accounts for paths that traverse
both space and time. Finally, we demonstrate how the BFS over evolving graphs
can be applied to mine citation networks.
Chinese: 演化图出现在数据间关系随时间变化的问题中。我们提出了一种针对演化图的广度优先搜索（BFS）算法，该算法计算两个不同时间节点间的最直接影响。通过简单的例子，我们表明邻接矩阵的朴素展开会错误统计时间路径数量。通过将演化图映射到等价静态图的邻接矩阵，我们证明了我们对BFS算法的推广能够正确统计穿越时空的路径。最后，我们展示了如何应用演化图上的BFS算法来挖掘引文网络。
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English: The flow equation method (Wegner 1994) is used as continuous unitary
transformation to construct perturbatively effective Hamiltonians. The method
is illustrated in detail for dimerized and frustrated antiferromagnetic S=1/2
chains. The effective Hamiltonians conserve the number of elementary
excitations which are S=1 magnons for the dimerized chains. The sectors of
different number of excitations are clearly separated. Easy-to-use results for
the gap, the dispersion and the ground state energies of the chains are
provided.
Chinese: 流方程法（Wegner 1994）被用作连续幺正变换，以构造逐级有效的哈密顿量。该方法对双链式和受挫反铁磁S=1/2链进行了详细说明。有效哈密顿量保持了基本激发粒子的数量，对于双链式链来说，这些基本激发粒子是S=1磁子。不同激发粒子数量的扇区被明显分离。链的能隙、色散关系和基态能量等易于使用的结果被提供。
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English: This article is devoted to the study of smooth desingularization, which are
customary employed in the definition of De Rham Intersection Cohomology with
differential forms. In this paper we work with the category of Thom-Mather
simple spaces. We construct a functor which sends each Thom-Mather simple space
into a smooth manifold called its primary unfolding. Hence we prove that the
primary unfoldings are unique up Thom-Mather isomorphisms.
Chinese: 本文致力于研究光滑去奇点化，它在用微分形式定义德·拉姆交式同调时被常规使用。在本文中我们研究Thom-Mather简单空间范畴。我们构造了一个将每个Thom-Mather简单空间映射为其称为初级展开的光滑流形。因此我们证明了初级展开在Thom-Mather同构意义下是唯一的。
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English: We examine the correspondence between the various notions of quasirandomness
for k-uniform hypergraphs and sigma-algebras related to measurable hypergraphs.
This gives a uniform formulation of most of the notions of quasirandomness for
dense hypergraphs which have been studied, with each notion of quasirandomness
corresponding to a sigma-algebra defined by a collection of subsets of [1,k].
We associate each notion of quasirandomness I with a collection of
hypergraphs, the I-adapted hypergraphs, so that G is quasirandom exactly when
it contains roughly the correct number of copies of each I-adapted hypergraph.
We then identify, for each I, a particular I-adapted hypergraph M_k[I] with the
property that if G contains roughly the correct number of copies of M_k[I] then
G is quasirandom in the sense of I. This generalizes recent results of
Kohayakawa, Nagle, R\"odl, and Schacht; Conlon, H\`an, Person, and Schacht; and
Lenz and Mubayi giving this result for some notions of quasirandomness.
Chinese: 我们研究了k-均匀超图的多种准随机性概念与与可测超图相关的σ代数之间的对应关系。这为已研究过的密集超图大多数准随机性概念提供了一个统一的表述，每个准随机性概念对应于由[1,k]的子集集合定义的σ代数。我们将每个准随机性概念I与一组超图，即I-适应超图相关联，使得G是准随机的当且仅当它包含大约正确的每个I-适应超图的副本数量。然后，对于每个I，我们确定一个特定的I-适应超图M_k[I]，它具有这样的性质：如果G包含大约正确的M_k[I]副本数量，那么G在I的意义上是准随机的。这推广了Kohayakawa、Nagle、Rödl和Schacht；Conlon、Hǎn、Person和Schacht；以及Lenz和Mubayi最近的一些研究成果，这些成果为某些准随机性概念提供了这一结果。
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English: Motivated by understanding the power of quantum computation with restricted
number of qubits, we give two complete characterizations of unitary quantum
space bounded computation. First we show that approximating an element of the
inverse of a well-conditioned efficiently encoded $2^{k(n)}\times 2^{k(n)}$
matrix is complete for the class of problems solvable by quantum circuits
acting on $\mathcal{O}(k(n))$ qubits with all measurements at the end of the
computation. Similarly, estimating the minimum eigenvalue of an efficiently
encoded Hermitian $2^{k(n)}\times 2^{k(n)}$ matrix is also complete for this
class. In the logspace case, our results improve on previous results of Ta-Shma
[STOC '13] by giving new space-efficient quantum algorithms that avoid
intermediate measurements, as well as showing matching hardness results.
Additionally, as a consequence we show that PreciseQMA, the version of QMA
with exponentially small completeness-soundess gap, is equal to PSPACE. Thus,
the problem of estimating the minimum eigenvalue of a local Hamiltonian to
inverse exponential precision is PSPACE-complete, which we show holds even in
the frustration-free case. Finally, we can use this characterization to give a
provable setting in which the ability to prepare the ground state of a local
Hamiltonian is more powerful than the ability to prepare PEPS states.
Interestingly, by suitably changing the parameterization of either of these
problems we can completely characterize the power of quantum computation with
simultaneously bounded time and space.
Chinese: 受限于量子计算中量子比特数量对计算能力的影响，我们给出了单位量子空间有界计算的两种完整刻画。首先，我们证明了近似一个良好条件、高效编码的 $2^{k(n)}\times 2^{k(n)}$ 矩阵的逆矩阵的元素对于量子电路在 $\mathcal{O}(k(n))$ 个量子比特上求解问题，且所有测量都在计算结束时进行的情况是完备的。同样，估计一个高效编码的厄米 $2^{k(n)}\times 2^{k(n)}$ 矩阵的最小特征值对于这一类问题也是完备的。在对数空间情况下，我们的结果通过提供新的空间高效量子算法，避免了中间测量，并展示了匹配的困难结果，从而改进了 Ta-Shma [STOC '13] 的先前结果。
此外，作为推论，我们证明了精确QMA（QMA的一种版本，具有指数级小的完备性和正确性差距）等于PSPACE。因此，估计局部哈密顿量最小特征值的逆指数精度问题是PSPACE完备的，我们证明了即使在无挫败情况下也是如此。最后，我们可以利用这一刻画来给出一个可证明的设置，其中准备局部哈密顿量基态的能力比准备PEPS状态的能力更强。
有趣的是，通过适当地改变这些问题的参数化，我们可以完全刻画同时受限于时间和空间的量子计算的能力。
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English: The transverse momentum ($p_{\rm T}$) and centrality dependence of the
nuclear modification factor $R_{\rm AA}$ of prompt and non-prompt J$/\psi$, the
latter originating from the weak decays of beauty hadrons, have been measured
by the ALICE collaboration in Pb$-$Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ =
5.02 TeV. The measurements are carried out through the ${\rm e}^{+}{\rm e}^{-}$
decay channel at midrapidity ($|y| < 0.9$) in the transverse momentum region
$1.5 < p_{\rm T} < 10$ GeV/$c$. Both prompt and non-prompt J$/\psi$
measurements indicate a significant suppression for $p_{\rm T} >$ 5 GeV/$c$,
which becomes stronger with increasing collision centrality. The results are
consistent with similar LHC measurements in the overlapping $p_{\rm T}$
intervals, and cover the kinematic region down to $p_{\rm T}$ = 1.5 GeV/$c$ at
midrapidity, not accessible by other LHC experiments. The suppression of prompt
J$/\psi$ in central and semicentral collisions exhibits a decreasing trend
towards lower transverse momentum, described within uncertainties by models
implementing J$/\psi$ production from recombination of c and $\overline{\rm c}$
quarks produced independently in different partonic scatterings. At high
transverse momentum, transport models including quarkonium dissociation are
able to describe the suppression for prompt J$/\psi$. For non-prompt J$/\psi$,
the suppression predicted by models including both collisional and radiative
processes for the computation of the beauty-quark energy loss inside the
quark$-$gluon plasma is consistent with measurements within uncertainties.
Chinese: 正交动量（$p_{\rm T}$）和中心性依赖的J/$\psi$核修正因子$R_{\rm AA}$，包括直接产生和非直接产生的J/$\psi$（后者来源于美底子强衰变），已由ALICE合作组在Pb$-$Pb碰撞中在$\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV下测量。这些测量通过${\rm e}^{+}{\rm e}^{-}$衰变通道在中部区域（$|y| < 0.9$）的转正交动量区间$1.5 < p_{\rm T} < 10$ GeV/$c$内进行。直接和非直接产生的J/$\psi$测量表明，对于$p_{\rm T} >$ 5 GeV/$c$有显著的抑制，随着碰撞中心性的增加，这种抑制变得更强。结果与LHC在重叠$p_{\rm T}$区间内的类似测量结果一致，并且覆盖了中部的动量区域下至$p_{\rm T}$ = 1.5 GeV/$c$，这是其他LHC实验无法访问的。在中心和半中心碰撞中，直接J/$\psi$的抑制显示出向较低转正交动量逐渐减小的趋势，这在不确定性范围内由实施J/$\psi$生产为c和$\overline{\rm c}$夸克独立在不同部分子散射中重新组合的模型描述。在高转正交动量时，包含夸克团簇解离的传输模型能够描述直接J/$\psi$的抑制。对于非直接产生的J/$\psi$，包括碰撞和辐射过程计算美底子夸克在夸克$-$胶子等离子体内部能量损失的模型预测的抑制与测量结果在不确定性范围内一致。
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English: Energy harvesting from vortex-induced vibrations is a promising technology
that relies on the vibrations of bluff bodies due to vortex shedding.
Increasing the vibration amplitude at a given free stream kinetic energy is
therefore equivalent to enhancing the efficiency of the harvesting device. In
this study, we assess the potential of alternate slot blowing to amplify force
fluctuations. Pressurized air is ejected alternatingly from the top and bottom
parts of the cylinder. Through experimentation in a low-speed wind tunnel
($Re=8,000$), we show that the magnitude of lift fluctuations can be enhanced
by up to a factor of three compared to the unforced flow when the actuation is
aligned with the natural vortex shedding frequency. Velocity field measurements
indicate that this is caused by strong streamline bending whereas, at a higher
forcing frequency, vortex shedding is suppressed. The results presented in this
article suggest that a significant increase in the dynamic load acting on a
cylinder can be achieved with carefully chosen active flow control parameters,
thereby promoting future energy harvesting applications.
Chinese: 从涡流诱导振动中获取能量是一种有前景的技术，它依赖于由于涡流脱落而导致的钝体振动。因此，在给定的自由流动能下增加振动幅度相当于提高了收集装置的效率。在本研究中，我们评估了交替槽吹风放大力波动潜力。压缩空气交替地从圆柱体的顶部和底部部分喷出。通过低速风洞（雷诺数Re=8,000）的实验，我们表明，当激励与自然涡流脱落频率一致时，升力波动的幅度可以比无强迫流动时提高三倍。速度场测量表明，这是由于强烈的流线弯曲造成的，而在较高的激励频率下，涡流脱落被抑制。本文中提出的结果表明，通过精心选择的主动流动控制参数，可以实现作用在圆柱体上的动态载荷的显著增加，从而促进未来的能量收集应用。
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English: We present surface spot maps of the K2V primary star in the pre-cataclysmic
variable binary system, V471 Tau. The spot maps show the presence of large high
latitude spots located at the sub-white dwarf longitude region. By tracking the
relative movement of spot groups over the course of four nights (eight rotation
cycles), we measure the surface differential rotation rate of the system.Our
results reveal that the star is rotating rigidly with a surface shear rate,
dOmega = 1.6 +/- 6 mrad/d. The single active star AB Dor has a similar spectral
type, rotation period, and activity level as the K star in V471 Tau but
displays much stronger surface shear (46 < dOmega < 58 mrad/d). Our results
suggest that tidal locking may inhibit differential rotation; this reduced
shear, however, does not affect the overall magnetic activity levels in active
K dwarfs.
Chinese: 我们展示了前超新星爆发变星双星系统V471 Tau主星K2V的表面斑点图。斑点图显示了位于亚白矮星经度区域的大高纬度斑点的存在。通过追踪斑点群在四夜（八次自转周期）内的相对运动，我们测量了该系统的表面微分旋转率。我们的结果表明，该星体以表面剪切率dOmega = 1.6 +/- 6 mrad/d的刚性旋转。单活动星AB Dor具有与V471 Tau中的K星相似的谱型、旋转周期和活动水平，但表现出更强的表面剪切（46 < dOmega < 58 mrad/d）。我们的结果表明，潮汐锁定可能抑制了微分旋转；然而，这种减小的剪切率并不影响活跃K矮星的整体磁活动水平。
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English: In this paper we present a model for accelerated expansion of the universe,
both during inflation and the present stage of the expansion, from four
dimensional $\mathcal{N}=1$ supergravity. We evaluate the tensor-to-scalar
ratio ($r\approx 0.00034$), the scalar spectral index ($n_s\approx 0.970$) and
the running spetral index ($dn_s/dk\approx -6\times10^{-5}$), and we notice
that these parameters are in agreement with Planck+WP+lensing data and with
BICEP2/Keck and Planck joint analysis, at $95\%$ CL. The number of e-folds is
$50$ or higher. The reheating period has an associated temperature
$T_R\sim10^{12}$ GeV, which agrees with the one required by thermal
leptogenesis. Regarding the scalar field as dark energy, the autonomous system
for it in the presence of a barotropic fluid provides a stable fixed point that
leads to a late-time accelerated expansion of the universe, with an equation of
state that mimics the cosmological constant ($w_\Phi\approx -0.997$).
Chinese: 在这篇论文中，我们提出了一种从四维 $\mathcal{N}=1$ 超引力出发的宇宙加速膨胀模型，包括膨胀过程中的通货膨胀阶段和当前膨胀阶段。我们评估了标量-张量比（$r\approx 0.00034$）、标量谱指数（$n_s\approx 0.970$）和谱指数的运行（$dn_s/dk\approx -6\times10^{-5}$），并注意到这些参数与Planck+WP+lensing数据以及BICEP2/Keck和Planck联合分析在95%置信水平上一致。折叠数是50或更高。再加热时期相关联的温度$T_R\sim10^{12}$ GeV，这与热轻子生成所需的温度一致。将标量场视为暗能量，在存在绝热流体的情况下，其自洽系统提供了一个稳定的固定点，导致宇宙在晚期加速膨胀，其状态方程类似于宇宙常数（$w_\Phi\approx -0.997$）。
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English: We show that a Hagedorn spectrum (i.e., spectrum where the number of hadrons
grows exponentially with the mass) emerges automatically in large $N_c$ QCD in
2+1 and 3+1 dimensions. The approach is based on the study of Euclidean space
correlation functions for composite operators constructed from quark and gluon
fields and exploits the fact that the short time behavior of the correlators is
known in QCD. The demonstration relies on one critical assumption: that
perturbation theory accurately describes the trace of the logarithm of a matrix
of point-to-point correlation functions in the regime where the perturbative
corrections to the asymptotically free value are small.
Chinese: 我们展示了在2+1和3+1维大Nc的QCD中，Hagedorn谱（即，随质量呈指数增长的强子谱）会自然出现。该方法基于研究由夸克和光子场构成的复合运算符在欧几里得空间中的关联函数，并利用了在QCD中关联函数短时行为的已知信息。证明依赖于一个关键假设：在扰动理论准确描述由点对点关联函数构成的矩阵的对数迹的极限情况下，微扰修正对自由值的影响很小。
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English: We derive the evolution equations of parton distribution functions
appropriate in different kinematic regions in a unified and simple way using
the resummation technique. They include the
Dokshitzer-Gribov-Lipatov-Altarelli-Parisi equation for large momentum transfer
$Q$, the Balitskii-Fadin-Kuraev-Lipatov equation for a small Bjorken variable
$x$, and the Ciafaloni-Catani-Fiorani-Marchesini equation which embodies the
above two equations. The relation among these equations is explored, and
possible applications of our approach are proposed.
Chinese: 我们使用重整化技术，以统一和简单的方式推导出适用于不同动力学区域的粒子分布函数的演化方程。它们包括适用于大动量转移$Q$的Dokshitzer-Gribov-Lipatov-Altarelli-Parisi方程，适用于小Bjorken变量$x$的Balitskii-Fadin-Kuraev-Lipatov方程，以及包含上述两个方程的Ciafaloni-Catani-Fiorani-Marchesini方程。探讨了这些方程之间的关系，并提出了我们方法的可能应用。
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English: Most theoretically motivated work in the offline reinforcement learning
setting requires precise uncertainty estimates. This requirement restricts the
algorithms derived in that work to the tabular and linear settings where such
estimates exist. In this work, we develop a novel method for incorporating
scalable uncertainty estimates into an offline reinforcement learning algorithm
called deep-SPIBB that extends the SPIBB family of algorithms to environments
with larger state and action spaces. We use recent innovations in uncertainty
estimation from the deep learning community to get more scalable uncertainty
estimates to plug into deep-SPIBB. While these uncertainty estimates do not
allow for the same theoretical guarantees as in the tabular case, we argue that
the SPIBB mechanism for incorporating uncertainty is more robust and flexible
than pessimistic approaches that incorporate the uncertainty as a value
function penalty. We bear this out empirically, showing that deep-SPIBB
outperforms pessimism based approaches with access to the same uncertainty
estimates and performs at least on par with a variety of other strong baselines
across several environments and datasets.
Chinese: 在离线强化学习设置中，大多数理论驱动的工作都需要精确的不确定性估计。这一需求限制了在该工作中推导出的算法仅适用于表格和线性设置，在这些设置中存在此类估计。在这项工作中，我们开发了一种新颖的方法，将可扩展的不确定性估计纳入名为deep-SPIBB的离线强化学习算法中，该方法将SPIBB算法系列扩展到具有更大状态和动作空间的环境中。我们利用深度学习社区最近在不确定性估计方面的创新，以获得更多可扩展的不确定性估计，并将其插入到deep-SPIBB中。虽然这些不确定性估计不能提供与表格情况相同的理论保证，但我们认为SPIBB机制在纳入不确定性方面比将不确定性作为值函数惩罚的悲观方法更为稳健和灵活。我们通过实证研究证实了这一点，表明deep-SPIBB在具有相同不确定性估计的悲观方法之上表现出色，并在多个环境和数据集上至少与各种其他强大基线表现相当。
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English: In the first Lecture, the Big Bang and the Standard Model of particle physics
are introduced, as well as the structure of the latter and open issues beyond
it. Neutrino physics is discussed in the second Lecture, with emphasis on
models for neutrino masses and oscillations. The third Lecture is devoted to
supersymmetry, including the prospects for discovering it at accelerators or as
cold dark matter. Inflation is reviewed from the viewpoint of particle physics
in the fourth Lecture, including simple models with a single scalar inflaton
field: the possibility that this might be a sneutrino is proposed. Finally, the
fifth Lecture is devoted to topics further beyond the Standard Model, such as
grand unification, baryo- and leptogenesis - that might be due to sneutrino
inflaton decays - and ultra-high-energy cosmic rays - that might be due to the
decays of metastable superheavy dark matter particles.
Chinese: 在第一讲中，介绍了大爆炸和粒子物理的标准模型，以及后者的结构和超越它的开放性问题。第二讲讨论了中微子物理，重点在于中微子质量和振荡的模型。第三讲致力于超对称性，包括在加速器或作为冷暗物质中发现它的前景。第四讲从粒子物理的角度回顾了通货膨胀，包括具有单个标量通货膨胀场的简单模型：提出了这可能是中微子场的机会。最后，第五讲致力于标准模型之外的课题，例如大统一、重子生成和轻子生成——可能源于中微子通货膨胀场的衰变——以及超高能宇宙射线——可能源于亚稳态超重暗物质粒子的衰变。
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English: In this paper, we studied the long-wave instability of the shear flows. When
the wavenumber of perturbation is larger than the critical value, the flow is
always neutrally stable. First, we obtain a new upper bound for the neutral
wavenumber $k_1\leq (p^2-1)\mu_1$, where $p>1$ and $\mu_1$ is the smallest
eigenvalue of Poincar\'{e}'s problem. Second, we find a new upper bound for the
imaginary part of the complex phase velocity $c_i \leq k_1 \Delta
U/\sqrt{\mu_1}$, where $\Delta U$ is the variance of the velocity. The new
bound is finite for all $k>0$ similar to the Howard's semicircle theorem, while
the previous ones by Craik and Banerjee et al would be infinity as
$k\rightarrow 0$. Third, we find a new upper bound of growth rate $\omega_i
\leq (p-1) \sqrt{\mu_1} \Delta U$. All the new bounds are much more strict than
the previous ones by H{\o}iland, Howard, Craik and Banerjee et al. Our results
also extend the inverse energy cascade theory by Kraichnan. As shear
instability is due to long-wave instability, it implies that the truncation of
long-waves may change the instability of shear flows.
Chinese: 在本文中，我们研究了剪切流的长时间稳定性。当扰动波数大于临界值时，流动始终是中性的。首先，我们得到了中性波数的一个新上界 $k_1 \leq (p^2-1)\mu_1$，其中 $p>1$，$\mu_1$ 是庞加莱问题最小的本征值。其次，我们找到了复相速度虚部的一个新上界 $c_i \leq k_1 \Delta U/\sqrt{\mu_1}$，其中 $\Delta U$ 是速度的方差。这个新上界类似于霍华德的半圆定理，对所有 $k>0$ 都是有限的，而克雷克和班纳吉等人之前的上界在 $k \rightarrow 0$ 时会趋于无穷。第三，我们找到了增长率的一个新上界 $\omega_i \leq (p-1) \sqrt{\mu_1} \Delta U$。所有新上界都比海兰德、霍华德、克雷克和班纳吉等人之前的上界严格得多。我们的结果还扩展了克拉因的逆能量级联理论。由于剪切不稳定性是由长时间不稳定性引起的，这意味着长时间波的截断可能会改变剪切流的稳定性。
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English: In this paper we review various models of curvature singularity free black
holes. In the first part of the review we describe semi-classical solutions of
the Einstein equations which, however, contains a "quantum" input through the
matter source. We start by reviewing the early model by Bardeen where the
metric is regularized by-hand through a short-distance cut-off, which is
justified in terms of non-linear electro-dynamical effects. This a toy-model
model useful to point-out the common features shared by all regular
semi-classical black holes. Then, we solve Einstein equations with a Gaussian
source encoding the quantum spread of an elementary particle. We identify, the
a priori arbitrary, Gaussian width with the Compton wavelength of the quantum
particle. This Compton-Gauss model leads to the estimate of a terminal density
that a gravitationally collapsed object can achieve. We identify this density
to be the Planck density, and reformulate the Gaussian model assuming this as
its peak density. All these models, are physically reliable as long as the
black hole mass is big enough with respect to the Planck mass. In the truly
Planckian regime, the semi-classical approximation breaks down. In this case, a
fully quantum black hole description is needed. In the last part of this paper,
we propose a non-geometrical quantum model of Planckian black hole implementing
the Holographic Principle and realizing the "classicalization" scenario
recently introduced by Dvali and collaborators. The classical relation between
the mass and radius of the black hole emerges only in the classical limit, far
away from the Planck scale.
Chinese: 在这篇论文中，我们回顾了各种无曲率奇点的黑洞模型。在综述的第一部分，我们描述了爱因斯坦方程的半经典解，然而，这些解通过物质源包含了“量子”输入。我们首先回顾了Bardeen早期模型，其中通过手动的短距离截断来正则化度规，这在非线性电动力学效应的术语下是合理的。这是一个玩具模型，有助于指出所有正则半经典黑洞共有的特征。然后，我们用高斯源解爱因斯坦方程，该源编码了基本粒子的量子扩散。我们将先验任意的高斯宽度与量子粒子的康普顿波长相对应。这个康普顿-高斯模型导致了估算一个引力坍缩物体可以达到的终端密度的结果。我们将这个密度识别为普朗克密度，并重新表述高斯模型，假设其为峰值密度。只要黑洞质量相对于普朗克质量足够大，所有这些模型都是物理上可靠的。在真正的普朗克尺度下，半经典近似失效。在这种情况下，需要完全的量子黑洞描述。在本文的最后部分，我们提出了一种非几何量子模型，用于描述普朗克尺度黑洞，该模型实现了霍金原理，并实现了Dvali及其合作者最近引入的“经典化”情景。黑洞的质量与半径之间的经典关系仅在经典极限下出现，远离普朗克尺度。
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English: Fibonacci polynomials are generalizations of Fibonacci numbers, so it is
natural to consider polynomial versions of the various results for Fibonacci
numbers. According to Hong, Pongsriiam, Bulawa, and Lee, the generating
function of the Fibonacci sequence in the domain of rational numbers,
$f(t)=t/(1-t-t^2)$, takes an integer value if and only if $t=F_{k}/F_{k+1}$ for
some $k \in \N$ or $t=-F_{k+1}/F_{k}$ for some $k \in \N^{+}$, where $F_{k}$ is
the $k$th Fibonacci number. This study is built upon their work by considering
polynomial sequences that satisfy the recurrence relation
$F_{i+2}(x)=axF_{i+1}(x)+bF_{i}(x)$ with initial values $(F_{0}(x),
F_{1}(x))=(0, 1)$, where $a$ and $b$ are positive integers such that $b|a$. As
an application, for a square-free natural number $d \in \N$, we verify the
results are of the same form as the above for the generating function of the
sequence satisfying the recurrence relation $F_{i+2}(\sqrt{d})=a\sqrt{d}
F_{i+1}(\sqrt{d})+bF_{i}(\sqrt{d})$ with initial values $(F_{0}(\sqrt{d}),
F_{1}(\sqrt{d}))=(0, 1)$.
Chinese: 费波那契多项式是对费波那契数的推广，因此考虑费波那契数各种结果的多项式版本是自然的。根据Hong、Pongsriiam、Bulawa和Lee的研究，有理数域中的费波那契序列生成函数$f(t)=t/(1-t-t^2)$只取整数值当且仅当$t=F_{k}/F_{k+1}$或$t=-F_{k+1}/F_{k}$，其中$F_{k}$是第$k$个费波那契数。本文在他们的工作基础上，考虑满足递推关系$F_{i+2}(x)=axF_{i+1}(x)+bF_{i}(x)$的多项式序列，其中初始值$(F_{0}(x), F_{1}(x))=(0, 1)$，且$a$和$b$是正整数，满足$b|a$。作为应用，对于无平方因子的自然数$d \in \N$，我们验证了满足递推关系$F_{i+2}(\sqrt{d})=a\sqrt{d}F_{i+1}(\sqrt{d})+bF_{i}(\sqrt{d})$的序列的生成函数的结果形式与上述相同，其中初始值$(F_{0}(\sqrt{d}), F_{1}(\sqrt{d}))=(0, 1)$。
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English: A set of introductory notes on the subject of data classification using a
linear classifier and least-squares cost function, and the negative effect of
the presence of outliers on the decision boundary of the linear discriminant.
We also show how a simple scaling could make the outlier less significant,
thereby obtaining a much better decision boundary. We present some numerical
results.
Chinese: 一组关于使用线性分类器和最小二乘成本函数进行数据分类的入门笔记，以及异常值对线性判别决策边界的影响。我们还展示了如何通过简单的缩放使异常值不那么显著，从而获得更好的决策边界。我们展示了某些数值结果。
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English: We present a hybrid quantum-classical variational scheme to enhance precision
in quantum metrology. In the scheme, both the initial state and the measurement
basis in the quantum part are parameterized and optimized via the classical
part. It enables the maximization of information gained about the measured
quantity. We discuss specific applications to 3D magnetic field sensing under
several dephasing noise modes. Indeed, we demonstrate its ability to
simultaneously estimate all parameters and surpass the standard quantum limit,
making it a powerful tool for metrological applications.
Chinese: 我们提出了一种混合量子-经典变分方案，以增强量子计量中的精度。在该方案中，量子部分的初始状态和测量基都通过经典部分进行参数化和优化。它使得关于测量量的信息获取最大化。我们讨论了在几种去相位噪声模式下的3D磁场传感的具体应用。实际上，我们展示了它同时估计所有参数并超越标准量子极限的能力，使其成为计量应用的有力工具。
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English: Recently Maleknejad and Sheikh-Jabbari have proposed a new model for
inflation with non-Abelian gauge fields (Gauge-flation), and they have studied
the model by numerical methods\cite{Sheikh}. In this model, the isotropy of
space-time is recovered by suitable combination of gauge configurations, and a
scalar field is constructed by gauge field and the scale factor, which produces
inflation period. In this work, exact solutions for the scalar field and the
Hubble parameter are presented and we provide analytic solutions for the
numerical results. We explicitly present Hubble parameter and fields as
functions of time and it is also demonstrated that in some conditions they are
damped oscillator. Moreover, reheating period in the model is discussed.
Chinese: 最近，Maleknejad和Sheikh-Jabbari提出了一种新的非阿贝尔规范场（规范-暴胀）通货膨胀模型，并使用数值方法研究了该模型\cite{Sheikh}。在这个模型中，通过合适的规范配置组合恢复了时空的各向同性，并通过规范场和尺度因子构建了一个标量场，这产生了通货膨胀时期。在这项工作中，我们提出了标量场和哈勃参数的精确解，并为数值结果提供了解析解。我们明确地将哈勃参数和场作为时间的函数呈现，并证明了在某些条件下它们是阻尼振荡器。此外，还讨论了模型中的再加热时期。
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English: In decision making a weight vector is often obtained from a reciprocal matrix
A that gives pairwise comparisons among n alternatives. The weight vector
should be chosen from among efficient vectors for A. Since the reciprocal
matrix is usually not consistent, there is no unique way of obtaining such a
vector. It is known that all weighted geometric means of the columns of A are
efficient for A. In particular, any column and the standard geometric mean of
the columns are efficient, the latter being an often used weight vector. Here
we focus on the study of the efficiency of the vectors in the (algebraic)
convex hull of the columns of A. This set contains the (right) Perron
eigenvector of A, a classical proposal for the weight vector, and the Perron
eigenvector of AA^{T} (the right singular vector of A), recently proposed as an
alternative. We consider reciprocal matrices A obtained from a consistent
matrix C by modifying at most three pairs of reciprocal entries contained in a
4-by-4 principal submatrix of C. For such matrices, we give necessary and
sufficient conditions for all vectors in the convex hull of the columns to be
efficient. In particular, this generalizes the known sufficient conditions for
the efficiency of the Perron vector. Numerical examples comparing the
performance of efficient convex combinations of the columns and weighted
geometric means of the columns are provided.
Chinese: 在决策过程中，通常从给定的n个替代方案的成对比较矩阵A中获取一个权重向量。权重向量应从A的有效向量中选择。由于倒数矩阵通常不一致，因此没有唯一的方法来获得这样的向量。已知A的所有加权几何平均列向量都是A的有效向量。特别是，任何列以及列的标准几何平均都是有效的，后者是一种常用的权重向量。在这里，我们专注于研究A的列的（代数）凸包中向量的有效性。这个集合包含A的（右）Perron特征向量，这是权重向量的经典建议，以及AA^{T}的Perron特征向量（A的右奇异向量），最近被提议作为替代方案。我们考虑通过修改C中4×4主子矩阵中包含的最多三对倒数条目来从一致矩阵C获得的倒数矩阵A。对于这样的矩阵，我们给出了所有在列的凸包中的向量都有效的必要和充分条件。特别是，这推广了已知Perron向量有效性的充分条件。提供了比较列的有效凸组合和列的加权几何平均性能的数值示例。
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English: Samples of amorphous MgSiO_3 annealed at temperature steps leading up to
their crystallisation temperature show a rise in photoluminescence activity,
peaking at ~450C. The photoluminescence band has a main peak at 595nm and a
weaker peak at 624nm. We present laboratory data to show that the maximum in
photoluminescence activity is related to substantial structural reordering that
occurs within a relatively narrow temperature range. We attribute the origin of
the photoluminescence to non-bridging oxygen hole centre defects, which form
around ordered nano-sized domain structures as a result of the breakup of
tetrahedral connectivity in the disordered inter-domain network, aided by the
loss of bonded OH. These defects are removed as crystallisation progresses,
resulting in the decrease and eventual loss of photoluminescence. Thermally
processed hydrogenated amorphous silicate grains could therefore represent a
potential carrier of extended red emission.
Chinese: 样品在接近其结晶温度的温度阶梯退火过程中，非晶态MgSiO_3的发光活性升高，峰值约为450℃。发光光谱带的主峰位于595nm，次峰位于624nm。我们提供了实验室数据，以表明发光活性的最大值与在相对较窄的温度范围内发生的显著结构重排有关。我们将光致发光的起源归因于非桥连氧空位中心缺陷，这些缺陷在无序的域间网络中四面体连接断裂并伴随OH键的损失后，围绕有序的纳米级域结构形成。随着结晶的进行，这些缺陷被消除，导致发光活性降低，最终消失。因此，热处理的氢化非晶态硅酸盐颗粒可能代表了一种扩展红光发射的潜在载体。
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English: Chiral cosmic strings are naturally produced at the end of D-term inflation
and they present very interesting cosmological consequences. In this work, we
investigate the formation and evolution of wakes by a chiral string. We show
that, for cold dark matter, the mechanism of forming wakes by a chiral string
is similar to the mechanism by an ordinary string.
Chinese: 手征宇宙弦在D项膨胀结束时自然产生，并呈现出非常有趣的宇宙学后果。在这项工作中，我们研究了手征弦产生的尾波的形成和演化。我们表明，对于冷暗物质，手征弦形成尾波的机制与普通弦的机制相似。
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English: Prime number theorem asserts that (at large $x$) the prime counting function
$\pi(x)$ is approximately the logarithmic integral $\mbox{li}(x)$. In the
intermediate range, Riemann prime counting function
$\mbox{Ri}^{(N)}(x)=\sum_{n=1}^N \frac{\mu(n)}{n}\mbox{Li}(x^{1/n})$ deviates
from $\pi(x)$ by the asymptotically vanishing sum
$\sum_{\rho}\mbox{Ri}(x^\rho)$ depending on the critical zeros $\rho$ of the
Riemann zeta function $\zeta(s)$. We find a fit $\pi(x)\approx
\mbox{Ri}^{(3)}[\psi(x)]$ [with three to four new exact digits compared to
$\mbox{li}(x)$] by making use of the Von Mangoldt explicit formula for the
Chebyshev function $\psi(x)$. Another equivalent fit makes use of the Gram
formula with the variable $\psi(x)$. Doing so, we evaluate $\pi(x)$ in the
range $x=10^i$, $i=[1\cdots 50]$ with the help of the first $2\times 10^6$
Riemann zeros $\rho$. A few remarks related to Riemann hypothesis (RH) are
given in this context.
Chinese: 素数定理断言，在大的$x$值下，素数计数函数$\pi(x)$近似等于对数积分$\mbox{li}(x)$。在中间范围内，黎曼素数计数函数$\mbox{Ri}^{(N)}(x)=\sum_{n=1}^N \frac{\mu(n)}{n}\mbox{Li}(x^{1/n})$与$\pi(x)$的偏差是由黎曼ζ函数$\zeta(s)$的临界零点$\rho$决定的渐近消失的和$\sum_{\rho}\mbox{Ri}(x^\rho)$。我们利用冯·曼戈尔特对Chebyshev函数$\psi(x)$的显式公式，找到了一个拟合$\pi(x)\approx \mbox{Ri}^{(3)}[\psi(x)]$（与$\mbox{li}(x)$相比有三个到四个新的精确数字）。另一种等效拟合使用了与变量$\psi(x)$相关的格拉姆公式。通过这种方式，我们借助前$2\times 10^6$个黎曼零点$\rho$，在$x=10^i$，$i=[1\cdots 50]$的范围内评估了$\pi(x)$。在此背景下，还给出了一些与黎曼猜想（RH）相关的一些评论。
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English: If a global continuous symmetry of a supersymmetric field theory is
spontaneously broken while preserving the supersymmetry, the resulting theory
has a massless superfield. One of its two bosonic degrees of freedom is the
familiar phase rotation of the usual massless Nambu-Goldstone boson, but the
other is a scale transformation. An indeterminate mass scale is thus generated.
In the fermion sector, a seesaw texture appears which may be suitable for a
possible light sterile neutrino. This feature persists even after the gauging
of the continuous symmetry or the breaking of the supersymmetry to resolve the
aforementioned mass-scale ambiguity.
Chinese: 如果在保持超对称性的情况下，超对称场理论中的全局连续对称性自发被破坏，那么得到的理论将具有一个无质量超场。其两个玻色子自由度之一是通常无质量Nambu-Goldstone玻色子的熟悉的相位旋转，而另一个则是尺度变换。因此，会生成一个不确定的质量尺度。在费米子部分，会出现一个跷跷板纹理，这可能适合可能的轻质量无质量中微子。这一特性即使在连续对称性的 gauge 化或超对称性的破坏以解决上述质量尺度的不确定性之后仍然存在。
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English: We present results of Monte Carlo simulations of the gauge glass model in
three dimensions using exchange Monte Carlo. We show for the first time clear
evidence of the vortex glass ordered phase at finite temperature. Using finite
size scaling we obtain estimates for the correlation length exponent, nu = 1.39
+/- 0.20, the correlation function exponent, eta = -0.47 +/- 0.07, and the
dynamic exponent z = 4.2 +/- 0.6. Using our values for z and nu we calculate
the resistivity exponent to be s = 4.5 +/- 1.1. Finally, we provide a plausible
lower bound on the the zero-temperature stiffness exponent, theta >= 0.18.
Chinese: 我们使用交换蒙特卡洛方法对三维的规范玻璃模型进行了蒙特卡洛模拟，并展示了在有限温度下清晰的涡旋玻璃有序相的证据。通过有限大小缩放，我们得到了相关长度指数ν=1.39±0.20，相关函数指数η=-0.47±0.07，以及动力学指数z=4.2±0.6的估计。利用我们的z和ν值，我们计算出了电阻率指数s=4.5±1.1。最后，我们提供了一个零温度刚度指数的可能的下限，θ≥0.18。
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English: As incarnations of gravity in its prime, black holes are arguably the best
target for us to demystify gravity. Keeping in mind the prominent role black
holes play in gravitational wave astronomy, it becomes a must for a theory to
possess black hole solutions with only measurable departures from their general
relativity counterparts. In this paper, we present black holes in a
tensor-vector-scalar representation of relativistic modified Newtonian
dynamics. We find that the theory allows Schwarzschild and nearly-Schwarzschild
black holes as solutions, while the nontrivial scalar and vector fields
generally diverge at the event horizon. Whether this is a physical pathology or
not poses a challenge for these solutions, and by extension, the model.
However, even if it is, this pathology could be overcome when the black hole
hair vanishes.
Chinese: 作为引力在其黄金时期的化身，黑洞可以说是我们揭开引力神秘面纱的最佳目标。考虑到黑洞在引力波天文学中扮演的重要角色，一个理论必须拥有只有可测量偏离其广义相对论对应物的黑洞解。在这篇论文中，我们以相对论修正牛顿动力学中的张量-矢量-标量表示法提出了黑洞。我们发现，该理论允许施瓦茨希尔德黑洞和近施瓦茨希尔德黑洞作为解，而非平凡的标量和矢量场通常在事件视界处发散。这究竟是否是一种物理疾病，对这些解以及由此扩展的模型构成了挑战。然而，即使如此，当黑洞的毛发消失时，这种疾病可能被克服。
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English: We present an analytic solution of type IIB supergravity plus D7-branes,
describing the addition of any number of flavors to the Klebanov-Strassler
background. The dual field theory and its self-similar RG flow, described by a
cascade of Seiberg dualities also in the presence of flavors, are discussed.
The solution indicates that the dual gauge theory enjoys a duality wall in the
UV. We stress the correspondence between Seiberg duality on the field theory
side, and large gauge transformations on the RR and NSNS potentials on the
gravity side. This contribution is mostly based on arxiv:0706.1238.
Chinese: 我们给出了一种IIB超引力加D7膜的解析解，描述了将任意数量味道添加到克莱班诺夫-斯特拉斯勒背景的过程。讨论了对偶场论及其在存在味道情况下的自相似RG流，该流由一系列西伯格对偶构成的级联描述。该解表明对偶规范理论在紫外区域存在对偶壁。我们强调了场论侧面的西伯格对偶与引力侧面的RR和NSNS势上的大规范变换之间的对应关系。这项工作主要基于arxiv:0706.1238。
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English: Recently, using a numerical surface cooling approach, we have shown that
highly energetic discrete breathers (DB) can form in the stiffest parts of
nonlinear network models of large protein structures. In the present study,
using an analytical approach, we extend our previous results to low-energy
discrete breathers as well as to smaller proteins
We confirm and further scrutinize the striking site selectiveness of energy
localisation in the presence of spatial disorder. In particular, we find that,
as a sheer consequence of disorder, a non-zero energy gap for exciting a DB at
a given site either exists or not. Remarkably, in the former case, the gaps
arise as result of the impossibility of exciting small-amplitude modes in the
first place. On the contrary, in the latter case, a small subset of linear edge
modes act as accumulation points, whereby DBs can be continued to arbitrary
small energies, while unavoidably approaching one of such normal modes. In
particular, the case of the edge mode seems peculiar, its dispersion relation
being simple and little system-dependent.
Concerning the structure-dynamics relationship, we find that the regions of
protein structures where DBs form easily (zero or small gaps) are unfailingly
the most highly connected ones, also characterized by weak local clustering.
Remarkably, a systematic analysis on a large database of enzyme structures
reveals that amino-acid residues involved in enzymatic activity tend to be
located in such regions. This finding reinforces the idea that localised modes
of nonlinear origin may play an important biological role, e.g. by providing a
ready channel for energy storage and/or contributing to lower energy barriers
of chemical reactions.
Chinese: 最近，我们使用数值表面冷却方法表明，在非线性网络模型的大蛋白质结构的刚性部分中，可以形成高能离散振子（DB）。在本研究中，我们使用分析方法将我们之前的结果扩展到低能离散振子以及较小的蛋白质。我们证实并进一步审查了在空间无序存在时能量局部化的显著位点选择性。特别是，我们发现，纯粹由于无序，给定位点上激发DB的能量间隙要么存在，要么不存在。值得注意的是，在前一种情况下，间隙的产生是由于首先无法激发小振幅模式。相反，在后一种情况下，一小部分线性边缘模式充当积累点，DB可以继续到任意小的能量，同时不可避免地接近这样的正常模式之一。特别是，边缘模式的情况似乎很特殊，其色散关系简单且与系统相关性小。
关于结构-动力学关系，我们发现蛋白质结构中易于形成DB的区域（零或小间隙）总是高度连接的，也以弱局部聚类为特征。值得注意的是，对酶结构的大型数据库的系统分析揭示，参与酶活性的氨基酸残基往往位于这些区域。这一发现加强了这样一种观点，即非线性起源的局部化模式可能发挥重要的生物学作用，例如通过提供能量储存的通道或有助于降低化学反应的能量障碍。
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English: Complex Langevin (CL) is a computational method to circumvent the numerical
sign problem with applications in finite-density quantum chromodynamics and the
real-time dynamics of quantum field theories. It has long been known that,
depending on the simulated system, CL does not always converge correctly. In
this work, we provide numerical evidence that the success or failure of the
complex Langevin method is deeply tied to the Lefschetz thimble structure of
the simulated system. This is demonstrated by constructing weight function
regularizations that deform the thimbles of systems with compact domains. Our
results indicate that CL converges correctly when the regularized system
exhibits a single relevant compact thimble. We introduce a bias correction to
retrieve the values of the original theory for parameter sets where a direct
complex Langevin approach fails. The effectiveness of this method is
illustrated using several toy models, including the cosine model and the SU(2)
and SU(3) Polyakov chains. Finally, we discuss the opportunities and
limitations of this regularization approach for lattice field theories.
Chinese: 复杂朗之万（CL）是一种计算方法，用于解决有限密度量子色动力学和量子场论实时动力学中的数值符号问题。长期以来，人们都知道，根据模拟的系统，CL并不总是能够正确收敛。在这项工作中，我们提供了数值证据，表明复杂朗之万方法的成功或失败与模拟系统的李弗席茨圆筒结构密切相关。这通过构建权重函数正则化来变形具有紧致域的系统圆筒得到证明。我们的结果表明，当正则化系统表现出单个相关紧致圆筒时，CL能够正确收敛。我们引入了一种偏差校正，以检索原始理论在直接复杂朗之万方法失败的反参数集的值。这种方法的有效性通过包括余弦模型和SU(2)和SU(3)波多尔斯基链在内的几个玩具模型进行了说明。最后，我们讨论了这种正则化方法在晶格场理论中的机会和局限性。
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English: This paper identifies OpenSDI, a challenge for spotting diffusion-generated
images in open-world settings. In response to this challenge, we define a new
benchmark, the OpenSDI dataset (OpenSDID), which stands out from existing
datasets due to its diverse use of large vision-language models that simulate
open-world diffusion-based manipulations. Another outstanding feature of
OpenSDID is its inclusion of both detection and localization tasks for images
manipulated globally and locally by diffusion models. To address the OpenSDI
challenge, we propose a Synergizing Pretrained Models (SPM) scheme to build up
a mixture of foundation models. This approach exploits a collaboration
mechanism with multiple pretrained foundation models to enhance generalization
in the OpenSDI context, moving beyond traditional training by synergizing
multiple pretrained models through prompting and attending strategies. Building
on this scheme, we introduce MaskCLIP, an SPM-based model that aligns
Contrastive Language-Image Pre-Training (CLIP) with Masked Autoencoder (MAE).
Extensive evaluations on OpenSDID show that MaskCLIP significantly outperforms
current state-of-the-art methods for the OpenSDI challenge, achieving
remarkable relative improvements of 14.23% in IoU (14.11% in F1) and 2.05% in
accuracy (2.38% in F1) compared to the second-best model in localization and
detection tasks, respectively. Our dataset and code are available at
https://github.com/iamwangyabin/OpenSDI.
Chinese: 本文识别了OpenSDI这一挑战，旨在识别开放世界环境中的扩散生成图像。为应对这一挑战，我们定义了一个新的基准，即OpenSDI数据集（OpenSDID），该数据集因其广泛使用模拟开放世界扩散操作的大规模视觉-语言模型而脱颖而出。OpenSDID的另一个突出特点是，它包含了由扩散模型全局和局部操纵的图像的检测和定位任务。为解决OpenSDI挑战，我们提出了一种综合预训练模型（SPM）方案，以构建基础模型的混合体。该方法利用了多种预训练基础模型之间的协作机制，以增强在OpenSDI环境中的泛化能力，超越了传统的通过多种预训练模型的提示和注意策略进行协同训练的方法。在此方案的基础上，我们引入了MaskCLIP模型，这是一种基于SPM的模型，它将对比语言-图像预训练（CLIP）与掩码自编码器（MAE）对齐。在OpenSDID上的广泛评估表明，MaskCLIP在OpenSDI挑战中的表现显著优于当前最先进的方法，分别在IoU（F1为14.11%）和准确率（F1为2.38%）上取得了显著的相对改进，分别为14.23%和2.05%。在检测和定位任务中，我们的模型比第二好的模型分别提高了14.23%和2.05%。我们的数据集和代码可在https://github.com/iamwangyabin/OpenSDI获取。
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English: Control of a dynamical system without the knowledge of dynamics is an
important and challenging task. Modern machine learning approaches, such as
deep neural networks (DNNs), allow for the estimation of a dynamics model from
control inputs and corresponding state observation outputs. Such data-driven
models are often utilized for the derivation of model-based controllers.
However, in general, there are no guarantees that a model represented by DNNs
will be controllable according to the formal control-theoretical meaning of
controllability, which is crucial for the design of effective controllers. This
often precludes the use of DNN-estimated models in applications, where formal
controllability guarantees are required. In this proof-of-the-concept work, we
propose a control-theoretical method that explicitly enhances models estimated
from data with controllability. That is achieved by augmenting the model
estimation objective with a controllability constraint, which penalizes models
with a low degree of controllability. As a result, the models estimated with
the proposed controllability constraint allow for the derivation of more
efficient controllers, they are interpretable by the control-theoretical
quantities and have a lower long-term prediction error. The proposed method
provides new insights on the connection between the DNN-based estimation of
unknown dynamics and the control-theoretical guarantees of the solution
properties. We demonstrate the superiority of the proposed method in two
standard classical control systems with state observation given by low
resolution high-dimensional images.
Chinese: 在没有动力学知识的情况下控制动态系统是一项重要且具有挑战性的任务。现代机器学习方法，如深度神经网络（DNNs），允许从控制输入和相应的状态观测输出中估计动力学模型。这类数据驱动模型通常用于基于模型的控制器推导。然而，一般来说，并不能保证由DNN表示的模型将根据控制理论中可控性的正式含义进行控制，这对于有效控制器的设计至关重要。这通常排除了在需要形式可控性保证的应用中使用DNN估计模型。在这项概念验证工作中，我们提出了一种控制理论方法，该方法明确地增强了从数据中估计的模型的可控性。这是通过在模型估计目标中增加一个可控性约束来实现的，该约束对可控性低的模型进行惩罚。因此，使用所提出的可控性约束估计的模型可以推导出更有效的控制器，它们可以通过控制理论量进行解释，并且具有更低的长期预测误差。所提出的方法对基于DNN的未知动力学估计与控制理论对解的性质保证之间的联系提供了新的见解。我们在两个标准经典控制系统中证明了所提出方法的优越性，这些系统的状态观测由低分辨率高维图像提供。
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English: Text-guided diffusion models make a paradigm shift in audio generation,
facilitating the adaptability of source audio to conform to specific textual
prompts. Recent works introduce inversion techniques, like DDIM inversion, to
zero-shot editing, exploiting pretrained diffusion models for audio
modification. Nonetheless, our investigation exposes that DDIM inversion
suffers from an accumulation of errors across each diffusion step, undermining
its efficacy. Moreover, existing editing methods fail to achieve effective
complex non-rigid music editing while maintaining essential content
preservation and high editing fidelity. To counteract these issues, we
introduce the Disentangled Inversion technique to disentangle the diffusion
process into triple branches, rectifying the deviated path of the source branch
caused by DDIM inversion. In addition, we propose the Harmonized Attention
Control framework, which unifies the mutual self-attention control and
cross-attention control with an intermediate Harmonic Branch to progressively
achieve the desired harmonic and melodic information in the target music.
Collectively, these innovations comprise the Disentangled Inversion Control
(DIC) framework, enabling accurate music editing while safeguarding content
integrity. To benchmark audio editing efficacy, we introduce ZoME-Bench, a
comprehensive music editing benchmark hosting 1,100 samples spread across ten
distinct editing categories. This facilitates both zero-shot and
instruction-based music editing tasks. Our method achieves unparalleled
performance in edit fidelity and essential content preservation, outperforming
contemporary state-of-the-art inversion techniques.
Chinese: 文本引导扩散模型在音频生成领域实现了范式转变，促进了源音频对特定文本提示的适应性。近期研究引入了反演技术，如DDIM反演，用于零样本编辑，利用预训练的扩散模型进行音频修改。然而，我们的研究表明DDIM反演在每一步扩散过程中存在误差累积问题，削弱了其有效性。此外，现有的编辑方法在保持核心内容保留和高编辑保真度的同时，无法实现有效的复杂非刚性音乐编辑。为了解决这些问题，我们引入了解耦反演技术，将扩散过程分解为三个分支，纠正DDIM反演导致的源分支偏离路径。此外，我们提出了协调注意力控制框架，将相互自注意力控制和交叉注意力控制与中间的和谐分支相结合，逐步在目标音乐中实现所需的和谐与旋律信息。总而言之，这些创新构成了解耦反演控制（DIC）框架，能够在保护内容完整性的同时实现精确的音乐编辑。为了基准化音频编辑效果，我们引入了ZoME-Bench，这是一个包含1100个样本、覆盖十个不同编辑类别的综合性音乐编辑基准，支持零样本和指令式音乐编辑任务。我们的方法在编辑保真度和核心内容保留方面实现了无与伦比的表现，优于当代最先进的反演技术。
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English: This paper studies the challenging problem of recovering motion from blur,
also known as joint deblurring and interpolation or blur temporal
super-resolution. The challenges are twofold: 1) the current methods still
leave considerable room for improvement in terms of visual quality even on the
synthetic dataset, and 2) poor generalization to real-world data. To this end,
we propose a blur interpolation transformer (BiT) to effectively unravel the
underlying temporal correlation encoded in blur. Based on multi-scale residual
Swin transformer blocks, we introduce dual-end temporal supervision and
temporally symmetric ensembling strategies to generate effective features for
time-varying motion rendering. In addition, we design a hybrid camera system to
collect the first real-world dataset of one-to-many blur-sharp video pairs.
Experimental results show that BiT has a significant gain over the
state-of-the-art methods on the public dataset Adobe240. Besides, the proposed
real-world dataset effectively helps the model generalize well to real blurry
scenarios. Code and data are available at https://github.com/zzh-tech/BiT.
Chinese: 本文研究了从模糊图像中恢复运动这一具有挑战性的问题，也称为联合去模糊和插值或模糊时间超分辨率。挑战有两方面：1）即使在合成数据集上，当前方法在视觉质量方面仍有相当大的提升空间；2）对现实世界数据的泛化能力较差。为此，我们提出了一种模糊插值转换器（BiT），以有效地解开模糊中编码的潜在时间相关性。基于多尺度残差 Swin Transformer 块，我们引入了双端时间监督和时对称集成策略，以生成用于时间变化运动渲染的有效特征。此外，我们设计了一种混合相机系统，以收集第一个真实世界的一对多模糊-清晰视频对数据集。实验结果表明，BiT 在公共数据集 Adobe240 上相对于现有方法有显著提升。此外，所提出的真实世界数据集有效地帮助模型很好地泛化到真实模糊场景。代码和数据可在 https://github.com/zzh-tech/BiT 获取。
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English: Correlation functions $C(t) \sim <\phi(t)\phi(0)>$ in ohmically damped
systems such as coupled harmonic oscillators or optical resonators can be
expressed as a single sum over modes $j$ (which are not power-orthogonal), with
each term multiplied by the Petermann factor (PF) $C_j$, leading to "excess
noise" when $|C_j| > 1$. It is shown that $|C_j| > 1$ is common rather than
exceptional, that $|C_j|$ can be large even for weak damping, and that the PF
appears in other processes as well: for example, a time-independent
perturbation $\sim\ep$ leads to a frequency shift $\sim \ep C_j$. The
coalescence of $J$ ($>1$) eigenvectors gives rise to a critical point, which
exhibits "giant excess noise" ($C_j \to \infty$). At critical points, the
divergent parts of $J$ contributions to $C(t)$ cancel, while time-independent
perturbations lead to non-analytic shifts $\sim \ep^{1/J}$.
Chinese: 在阻尼系统中，例如耦合谐振子或光学谐振器，相关函数 $C(t) \sim <\phi(t)\phi(0)>$ 可以表示为关于模式 $j$ 的单一求和（这些模式不是功率正交的），每个项乘以彼得曼因子（PF）$C_j$，当 $|C_j| > 1$ 时会导致“超额噪声”。研究表明 $|C_j| > 1$ 是普遍而非例外的情况，即使对于弱阻尼，$|C_j|$ 也可以很大，并且彼得曼因子也出现在其他过程中：例如，一个与时间无关的扰动 $\sim\ep$ 会导致频率偏移 $\sim \ep C_j$。$J$ ($>1$) 个本征向量的合并会产生一个临界点，该临界点表现出“巨型超额噪声” ($C_j \to \infty$)。在临界点处，$J$ 对 $C(t)$ 的贡献的发散部分会相互抵消，而与时间无关的扰动会导致非解析的偏移 $\sim \ep^{1/J}$。
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English: Existing methods utilizing spatial information for sound source separation
require prior knowledge of the direction of arrival (DOA) of the source or
utilize estimated but imprecise localization results, which impairs the
separation performance, especially when the sound sources are moving. In fact,
sound source localization and separation are interconnected problems, that is,
sound source localization facilitates sound separation while sound separation
contributes to refined source localization. This paper proposes a method
utilizing the mutual facilitation mechanism between sound source localization
and separation for moving sources. The proposed method comprises three stages.
The first stage is initial tracking, which tracks each sound source from the
audio mixture based on the source signal envelope estimation. These tracking
results may lack sufficient accuracy. The second stage involves mutual
facilitation: Sound separation is conducted using preliminary sound source
tracking results. Subsequently, sound source tracking is performed on the
separated signals, thereby refining the tracking precision. The refined
trajectories further improve separation performance. This mutual facilitation
process can be iterated multiple times. In the third stage, a neural beamformer
estimates precise single-channel separation results based on the refined
tracking trajectories and multi-channel separation outputs. Simulation
experiments conducted under reverberant conditions and with moving sound
sources demonstrate that the proposed method can achieve more accurate
separation based on refined tracking results.
Chinese: 现有的利用空间信息进行声源分离的方法需要声源到达方向（DOA）的先验知识，或者使用估计但不精确的定位结果，这会损害分离性能，尤其是在声源移动时。事实上，声源定位和分离是相互关联的问题，即声源定位促进声源分离，而声源分离有助于精细的声源定位。本文提出了一种利用移动声源之间声源定位与分离相互促进机制的方法。该方法包含三个阶段。第一阶段是初始跟踪，它基于源信号包络估计，从音频混合物中跟踪每个声源。这些跟踪结果可能缺乏足够的精度。第二阶段涉及相互促进：使用初步的声源跟踪结果进行声源分离。随后，对分离后的信号进行声源跟踪，从而提高跟踪精度。精细的轨迹进一步提高了分离性能。这个相互促进的过程可以迭代多次。第三阶段，神经波束形成器根据精细的跟踪轨迹和多通道分离输出估计精确的单通道分离结果。在混响条件和移动声源下的仿真实验表明，该方法能够基于精细的跟踪结果实现更精确的分离。
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English: We present a space-time description of hadronization of highly virtual quarks
originating from a deep-inelastic electron scattering (DIS). Important
ingredients of our approach are the time- and energy--dependence of the density
of energy loss for gluon radiation, the Sudakov's suppression of no radiation,
and the effect of color transparency, which suppresses final state interaction
of the produced colorless wave packet. The model is in a good agreement with
available data on leading hadron production off nucleons and nuclei. The
optimal energy range for study of the hadronization dynamics with nuclear
target is found to be a few tens of GeV, particularly energies available in the
experiment HERMES.
Chinese: 我们提出了一种时空描述，用于描述来自深度非弹性电子散射（DIS）的高能虚拟夸克强子化过程。我们方法的重要组成部分包括：光子辐射能量损失密度的时空依赖性、Sudakov无辐射抑制效应，以及颜色透明性对产生无色波包最终态相互作用的抑制。该模型与关于核子及核上带领先子体产生的现有数据吻合良好。我们发现，使用核靶研究强子化动力学的最优能量范围是几十GeV，特别是HERMES实验可用的能量。
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English: Residual entropy, which reflects the degrees of freedom in a system at
absolute zero temperature, is crucial for understanding quantum and classical
ground states. Despite its key role in explaining low-temperature phenomena and
ground state degeneracy, accurately measuring residual entropy remains a
difficult task owing to computational limitations. In this Letter, we introduce
the temperature incremental Monte Carlo (TIMC) method, our approach to
overcoming these challenges. The TIMC method incrementally calculates the
partition function ratio of neighboring temperatures within Monte Carlo
simulations, enabling precise entropy calculations and revealing other
temperature-dependent properties in a single computational sweep of
temperatures. We have rogorously tested TIMC on several complex systems,
including the frustrated antiferromagnetic Ising model on both C60 and 2D
triangular lattices, the Newman-Moore glassy model, and a 2D quantum transverse
field Ising model. Notably, our method overcomes the difficulties encountered
in partition function measurements when mapping $d$-dimensional quantum models
to $d+1$-dimensional classical counterparts. These challenges arise from
singular interactions that emerge in the small $\Delta_\tau$ limit during the
quantum-to-classical mapping procedure. The TIMC method enables precise entropy
calculations across the entire temperature range, as demonstrated in our
studies of frustrated spin models, glassy phases, and phases exhibiting
spontaneous symmetry breaking. This method's capability to calculate residual
entropy could provide insights when applied to systems lacking analytical
solutions.
Chinese: 剩余熵，它反映了系统在绝对零度下的自由度，对于理解量子态和经典基态至关重要。尽管它在解释低温现象和基态简并性方面起着关键作用，但由于计算限制，准确测量剩余熵仍然是一个难题。在这封信中，我们介绍了温度增量蒙特卡洛（TIMC）方法，这是我们克服这些挑战的方法。TIMC方法在蒙特卡洛模拟中逐步计算相邻温度的配分函数比率，使得精确的熵计算成为可能，并在单个温度计算过程中揭示其他温度相关的性质。我们已经对几个复杂系统进行了严格的TIMC测试，包括C60和二维三角形晶格上的反铁磁Ising模型、Newman-Moore玻璃模型以及二维量子横向场Ising模型。值得注意的是，我们的方法克服了将$d$维量子模型映射到$d+1$维经典对应物时在配分函数测量中遇到的困难。这些挑战源于在量子到经典映射过程中，$\Delta_\tau$极限下出现的奇异相互作用。TIMC方法能够在整个温度范围内进行精确的熵计算，正如我们在研究反铁磁模型、玻璃相和自发对称破缺相的研究中所展示的那样。该方法计算剩余熵的能力，当应用于缺乏解析解的系统时，可能提供洞察力。
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English: Green hydrogen has multiple use cases and is produced from renewable energy,
such as solar or wind energy. It can be stored in large quantities, decoupling
renewable energy generation from its use, and is therefore considered essential
for achieving a climate-neutral economy. The intermittency of renewable energy
generation and the stochastic nature of demand are, however, challenging
factors for the dynamic planning of hydrogen storage and transportation. This
holds particularly in the early-adoption phase when hydrogen distribution
occurs through vehicle-based networks. We therefore address the Dynamic
Inventory Routing Problem (DIRP) under stochastic supply and demand with direct
deliveries for the vehicle-based distribution of hydrogen. To solve this
problem, we propose a Constrained Reinforcement Learning (CRL) framework that
integrates constraints into the learning process and incorporates parameterized
post-decision state value predictions. Additionally, we introduce
Lookahead-based CRL (LCRL), which improves decision-making over a multi-period
horizon to enhance short-term planning while maintaining the value predictions.
Our computational experiments demonstrate the efficacy of CRL and LCRL across
diverse instances. Our learning methods provide near-optimal solutions on small
scale instances that are solved via value iteration. Furthermore, both methods
outperform typical deep learning approaches such as Proximal Policy
Optimization, as well as classical inventory heuristics, such as
(s,S)-policy-based and Power-of-Two-based heuristics. Furthermore, LCRL
achieves a 10% improvement over CRL on average, albeit with higher
computational requirements. Analyses of optimal replenishment policies reveal
that accounting for stochastic supply and demand influences these policies,
showing the importance of our addition to the DIRP.
Chinese: 绿色氢气有多种应用场景，由可再生能源如太阳能或风能生产。它可以大量存储，将可再生能源的生产与其使用脱钩，因此被认为是实现气候中和经济体所必需的。然而，可再生能源生产的间歇性和需求的不确定性是氢气储存和运输动态规划中的重大挑战。尤其是在氢气分配通过基于车辆的网络的早期采用阶段，我们因此针对在随机供需下的车辆基氢气分配提出了动态库存路线问题（DIRP）。为了解决这个问题，我们提出了一种约束强化学习（CRL）框架，该框架将约束集成到学习过程中，并包含参数化的后决策状态价值预测。此外，我们引入了基于前瞻的CRL（LCRL），它通过在多周期范围内改进决策制定来增强短期规划，同时保持价值预测。我们的计算实验展示了CRL和LCRL在多种情况下的有效性。我们的学习方法在小规模实例上提供了接近最优的解决方案，这些实例通过值迭代求解。此外，这两种方法均优于典型的深度学习方法如Proximal Policy Optimization，以及经典的库存启发式方法如(s,S)策略和Power-of-Two策略。进一步地，LCRL在平均情况下比CRL提高了10%，尽管计算要求更高。对最优补货政策的分析揭示了考虑随机供需对补货政策的影响，显示了我们在DIRP中的添加的重要性。
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English: We consider the ratio between the double and single Higgs production cross
sections and examine the prospect of measuring the trilinear Higgs
self-coupling using this observable. Such a ratio has a reduced theoretical
(scale) uncertainty than the double Higgs cross section. We find that with
600/fb, the 14 TeV LHC can constraint the trilinear Higgs self coupling to be
positive, and with 3000/fb one could measure it with a +30 % {-20 %}) accuracy.
Chinese: 我们考虑双Higgs和单Higgs产生截面之间的比率，并考察利用这个可观测量测量三线性Higgs自耦合的前景。这样的比率比双Higgs截面具有更小的理论（尺度）不确定性。我们发现，在600/fb的条件下，14 TeV的LHC可以约束三线性Higgs自耦合为正值，而在3000/fb的条件下，可以以+30% {-20%}的精度进行测量。
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English: We study the sensitivity of top pair production at the Large Hadron Collider
(LHC) to the nature of an underlying Z' boson, including full tree level
standard model background effects and interferences. We demonstrate that
exploiting combinations of asymmetry observables will enable one to distinguish
between a selection of `benchmark' Z' models while assuming realistic final
state reconstruction efficiencies and error estimates.
Chinese: 我们研究了在大型强子对撞机（LHC）上顶对生成对于潜在Z'玻色子本质的敏感性，包括标准模型背景的全树级效应和相互干扰。我们展示了通过结合不对称性观测结果，在假定实际最终态重构效率和误差估计的情况下，可以区分一系列“基准”Z'模型。
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English: In this article, we propose a novel variable screening method for linear
models named as conditional screening via ordinary least squares projection
(COLP). COLP can take advantage of prior knowledge concerning certain active
predictors by eliminating the adverse impact of their coefficients in the
estimation of remaining ones and thus significantly enhance the screening
accuracy. We prove its sure-screening property under reasonable assumptions and
demonstrate its utility in an application to a leukemia dataset. Moreover,
based on the conditional approach, we introduce an iterative algorithm named as
forward screening via ordinary least squares projection (FOLP), which not only
could exploit the prior information more effectively, but also has promising
performance when no prior knowledge is available using a data-driven
conditioning set. Extensive simulation studies are carried out to demonstrate
the competence of both proposed methods.
Chinese: 在本文中，我们提出了一种名为普通最小二乘投影条件筛选（COLP）的线性模型变量筛选新方法。COLP通过消除某些活跃预测变量系数在剩余变量估计中的不良影响，可以利用先验知识，从而显著提高筛选精度。我们在合理假设下证明了其确筛性，并在白血病数据集的应用中验证了其有效性。此外，基于条件筛选方法，我们引入了一种名为普通最小二乘投影前向筛选（FOLP）的迭代算法，该算法不仅能够更有效地利用先验信息，而且当没有先验知识可用时，使用数据驱动条件集也能表现出良好性能。我们进行了广泛的模拟研究，以证明这两种方法的有效性。
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English: We present the detection of 89 low surface brightness (LSB), and thus low
stellar density galaxy candidates in the Perseus cluster core, of the kind
named "ultra-diffuse galaxies", with mean effective V-band surface brightnesses
24.8-27.1 mag arcsec$^{-2}$, total V-band magnitudes -11.8 to -15.5 mag, and
half-light radii 0.7-4.1 kpc. The candidates have been identified in a deep
mosaic covering 0.3 square degrees, based on wide-field imaging data obtained
with the William Herschel Telescope. We find that the LSB galaxy population is
depleted in the cluster centre and only very few LSB candidates have half-light
radii larger than 3 kpc. This appears consistent with an estimate of their
tidal radius, which does not reach beyond the stellar extent even if we assume
a high dark matter content (M/L=100). In fact, three of our candidates seem to
be associated with tidal streams, which points to their current disruption.
Given that published data on faint LSB candidates in the Coma cluster - with
its comparable central density to Perseus - show the same dearth of large
objects in the core region, we conclude that these cannot survive the strong
tides in the centres of massive clusters.
Chinese: 我们报告了在Perseus星系团核心检测到89个低表面亮度（LSB）的候选体，即低恒星密度星系，这类星系被称为“超模糊星系”，它们的平均有效V带表面亮度范围为24.8-27.1 mag arcsec$^{-2}$，总V带亮度范围为-11.8至-15.5 mag，半光半径为0.7-4.1 kpc。这些候选体基于William Herschel望远镜获得的宽场成像数据，覆盖了0.3平方度的深拼接图像。我们发现，低表面亮度的星系群体在星系团中心被耗尽，只有极少数的低表面亮度候选体的半光半径大于3 kpc。这似乎与它们的潮汐半径的估计一致，即使我们假设暗物质含量很高（M/L=100），它们的潮汐半径也不会超过恒星的范围。事实上，我们有三个候选体似乎与潮汐流相关联，这表明它们当前正在被破坏。鉴于在Coma星系团（其中心密度与Perseus相当）上关于微弱LSB候选体的已发表数据中，核心区域同样缺少大型物体，我们得出结论，这些星系在大星系团中心强烈的潮汐作用下无法生存。
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English: In this note, we prove that a 3-dimensional steady Ricci soliton is
rotationally symmetric if its scalar curvature $R(x)$ satisfies
$$\frac{C_0^{-1}}{\rho(x)}\le R(x)\le \frac{C_0}{\rho(x)}$$ for some constant
$C_0>0$, where $\rho(x)$ denotes the distance from a fixed point $x_0$. Our
result doesn't assume that the soliton is $\kappa$-noncollapsed.
Chinese: 在这篇笔记中，我们证明了一个三维稳态Ricci孤子如果其标量曲率$R(x)$满足
$$\frac{C_0^{-1}}{\rho(x)}\le R(x)\le \frac{C_0}{\rho(x)}$$
对于某个常数$C_0>0$，则它是旋转对称的，其中$\rho(x)$表示从固定点$x_0$的距离。我们的结果并不假设孤子是$\kappa$-非塌缩的。
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English: In humans and animals, curriculum learning -- presenting data in a curated
order - is critical to rapid learning and effective pedagogy. Yet in machine
learning, curricula are not widely used and empirically often yield only
moderate benefits. This stark difference in the importance of curriculum raises
a fundamental theoretical question: when and why does curriculum learning help?
In this work, we analyse a prototypical neural network model of curriculum
learning in the high-dimensional limit, employing statistical physics methods.
Curricula could in principle change both the learning speed and asymptotic
performance of a model. To study the former, we provide an exact description of
the online learning setting, confirming the long-standing experimental
observation that curricula can modestly speed up learning. To study the latter,
we derive performance in a batch learning setting, in which a network trains to
convergence in successive phases of learning on dataset slices of varying
difficulty. With standard training losses, curriculum does not provide
generalisation benefit, in line with empirical observations. However, we show
that by connecting different learning phases through simple Gaussian priors,
curriculum can yield a large improvement in test performance. Taken together,
our reduced analytical descriptions help reconcile apparently conflicting
empirical results and trace regimes where curriculum learning yields the
largest gains. More broadly, our results suggest that fully exploiting a
curriculum may require explicit changes to the loss function at curriculum
boundaries.
Chinese: 在人类和动物中，课程学习——以精心编排的顺序呈现数据——对于快速学习和有效的教学至关重要。然而，在机器学习中，课程并不广泛使用，并且实证研究表明，课程通常只能带来中等的好处。这种对课程重要性的明显差异引发了一个基本的理论问题：何时以及为什么课程学习有帮助？
在这项工作中，我们分析了高维极限下课程学习的典型神经网络模型，采用了统计物理方法。原则上，课程可以改变模型的学习速度和渐近性能。为了研究前者，我们提供了在线学习设置的精确描述，证实了长期以来的实验观察，即课程可以适度地加快学习速度。为了研究后者，我们推导了批量学习设置中的性能，其中网络在数据集切片的逐步学习阶段中训练到收敛。与经验观察一致，使用标准的训练损失，课程并不提供泛化好处。然而，我们表明，通过通过简单的高斯先验连接不同的学习阶段，课程可以在测试性能上带来很大的改进。总的来说，我们的简化分析描述有助于调和看似矛盾的经验结果，并追踪课程学习带来最大收益的领域。更广泛地说，我们的结果表明，充分利用课程可能需要在课程边界处对损失函数进行显式的改变。
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English: We introduce Adversarial Diffusion Distillation (ADD), a novel training
approach that efficiently samples large-scale foundational image diffusion
models in just 1-4 steps while maintaining high image quality. We use score
distillation to leverage large-scale off-the-shelf image diffusion models as a
teacher signal in combination with an adversarial loss to ensure high image
fidelity even in the low-step regime of one or two sampling steps. Our analyses
show that our model clearly outperforms existing few-step methods (GANs, Latent
Consistency Models) in a single step and reaches the performance of
state-of-the-art diffusion models (SDXL) in only four steps. ADD is the first
method to unlock single-step, real-time image synthesis with foundation models.
Code and weights available under
https://github.com/Stability-AI/generative-models and
https://huggingface.co/stabilityai/ .
Chinese: 我们介绍了对抗扩散蒸馏（ADD），这是一种新颖的训练方法，能够在仅1-4步的情况下高效采样大规模基础图像扩散模型，同时保持高图像质量。我们采用分数蒸馏，将大规模现成图像扩散模型作为教师信号，并结合对抗损失，以确保即使在单步或两步的低步采样模式下也能保持高图像保真度。我们的分析表明，我们的模型在单步情况下明显优于现有的少步方法（GANs、潜一致性模型），并在仅四步时达到最先进的扩散模型（SDXL）的性能。ADD是首个解锁基于基础模型的单步实时图像合成的方法。代码和权重可在https://github.com/Stability-AI/generative-models和https://huggingface.co/stabilityai上获取。
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English: Lesion detection is an important problem within medical imaging analysis.
Most previous work focuses on detecting and segmenting a specialized category
of lesions (e.g., lung nodules). However, in clinical practice, radiologists
are responsible for finding all possible types of anomalies. The task of
universal lesion detection (ULD) was proposed to address this challenge by
detecting a large variety of lesions from the whole body. There are multiple
heterogeneously labeled datasets with varying label completeness: DeepLesion,
the largest dataset of 32,735 annotated lesions of various types, but with even
more missing annotation instances; and several fully-labeled single-type lesion
datasets, such as LUNA for lung nodules and LiTS for liver tumors. In this
work, we propose a novel framework to leverage all these datasets together to
improve the performance of ULD. First, we learn a multi-head multi-task lesion
detector using all datasets and generate lesion proposals on DeepLesion.
Second, missing annotations in DeepLesion are retrieved by a new method of
embedding matching that exploits clinical prior knowledge. Last, we discover
suspicious but unannotated lesions using knowledge transfer from single-type
lesion detectors. In this way, reliable positive and negative regions are
obtained from partially-labeled and unlabeled images, which are effectively
utilized to train ULD. To assess the clinically realistic protocol of 3D
volumetric ULD, we fully annotated 1071 CT sub-volumes in DeepLesion. Our
method outperforms the current state-of-the-art approach by 29% in the metric
of average sensitivity.
Chinese: 病变检测是医学影像分析中的一个重要问题。
大多数先前的研究都集中在检测和分割特定类型的病变（例如，肺结节）。然而，在临床实践中，放射科医生负责发现所有可能的异常类型。通用病变检测（ULD）的任务是通过检测全身各种类型的病变来应对这一挑战。存在多个异构标签的数据集，标签完整性各不相同：DeepLesion，包含32,735个不同类型病变标注的最大数据集，但存在更多缺失标注实例；以及几个完全标注的单类型病变数据集，如LUNA用于肺结节和LiTS用于肝肿瘤。在这项工作中，我们提出了一种新颖的框架，以利用所有这些数据集来提高ULD的性能。首先，我们使用所有数据集学习一个多头多任务病变检测器，并在DeepLesion上生成病变提议。其次，通过一种新的嵌入匹配方法检索DeepLesion中的缺失标注，该方法利用了临床先验知识。最后，我们通过从单类型病变检测器中转移知识来发现可疑但未标注的病变。通过这种方式，从部分标注和无标注图像中获得了可靠的阳性和阴性区域，这些区域被有效地用于训练ULD。为了评估3D体积ULD的临床现实方案，我们在DeepLesion中对1071个CT亚体积进行了全面标注。我们的方法在平均敏感度指标上比当前最先进的方法提高了29%。
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English: The puzzle remains in the large discrepancy between neutron lifetime measured
by the two distinct experimental approaches -- counts of beta decays in a
neutron beam and storage of ultracold neutrons in a potential trap, namely, the
beam method versus the bottle method. In this paper, we propose a new
experiment to measure the neutron lifetime in a cold neutron beam with a
sensitivity goal of 0.1% or sub-1 second. The neutron beta decays will be
counted in a superfluid helium-4 scintillation detector at 0.5 K, and the
neutron flux will be simultaneously monitored by the helium-3 captures in the
same volume. The cold neutron beam must be of wavelength $\lambda>16.5$ A to
eliminate scattering with superfluid helium. A new precise measurement of
neutron lifetime with the beam method of unique inherent systematic effects
will greatly advance in resolving the puzzle.
Chinese: 谜团仍然存在于两种不同的实验方法测量中子寿命之间的巨大差异——即通过中子束中的β衰变计数和将超冷中子存储在潜在陷阱中，也就是束方法与瓶方法的对比。在这篇论文中，我们提出了一种新的实验方法，以0.1%或亚秒的灵敏度目标测量冷中子束中的中子寿命。中子β衰变将在0.5 K的超流体氦-4闪烁探测器中进行计数，同时通过同一体积中的氦-3捕获来同时监测中子通量。冷中子束的波长必须大于$\lambda>16.5$ A，以消除与超流体氦的散射。使用具有独特固有系统效应的束方法进行中子寿命的新精确测量将大大推进解决这个谜团。
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English: A pearl's distinguished beauty and toughness are attributable to the periodic
stacking of aragonite tablets known as nacre. Nacre has naturally occurring
mesoscale periodicity that remarkably arises in the absence of discrete
translational symmetry. Gleaning the inspiring biomineral design of a pearl
requires quantifying its structural coherence and understanding the stochastic
processes that influence formation. By characterizing the entire structure of
pearls (~3 mm) in cross-section at high resolution, we show nacre has
medium-range mesoscale periodicity. Self-correcting growth mechanisms actively
remedy disorder and topological defects of the tablets and act as a
countervailing process to long-range disorder. Nacre has a correlation length
of roughly 16 tablets (~5.5 um) despite persistent fluctuations and topological
defects. For longer distances (> 25 tablets, ~8.5 um), the frequency spectrum
of nacre tablets follows f^(-1.5) behavior suggesting growth is coupled to
external stochastic processes-a universality found across disparate natural
phenomena which now includes pearls.
Chinese: 珍珠的非凡美感和韧性归因于被称为珍珠层的方解石板的周期性堆叠。珍珠层具有自然发生的介观周期性，这种周期性在没有离散平移对称性的情况下显著出现。采撷珍珠的启发式生物矿物设计需要量化其结构连贯性，并理解影响其形成的随机过程。通过对珍珠（约3毫米）的高分辨率横截面进行表征，我们展示了珍珠层具有中程介观周期性。自我校正的生长机制积极地修复板片的混乱和拓扑缺陷，并作为对抗长程混乱的过程。尽管存在持续的波动和拓扑缺陷，珍珠层的关联长度约为16个板片（约5.5微米）。对于更长的距离（>25个板片，约8.5微米），珍珠层板片的频率谱遵循f^(-1.5)行为，这表明生长与外部随机过程相关联——这是一种在众多不同自然现象中发现的普适性，现在包括珍珠。
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English: The main objective of this article is part of a research program to link the
dynamics of fluid flows with the structure and its transitions in the physical
spaces. As a prototype of problem and to demonstrate the main ideas, we study
the two-dimensional Rayleigh-Benard convection. The analysis is based on two
recently developed nonlinear theories: geometric theory for incompressible
flows [10] and the bifurcation and stability theory for nonlinear dynamical
systems (both finite and infinite dimensional) [9]. We have shown in [8] that
the Rayleigh-Benard problem bifurcates from the basic state to an attractor A_R
when the Rayleigh number R crosses the first critical Rayleigh number R_c for
all physically sound boundary conditions, regardless of the multiplicity of the
eigenvalue R_c for the linear problem. In this article, in addition to a
classification of the bifurcated attractor A_R, the structure and its
transitions of the solutions in the physical space is classified, leading to
the existence and stability of two different flows structures: pure rolls and
rolls separated by a cross the channel flow. It appears that the structure with
rolls separated by a cross channel flow has not been carefully examined
although it has been observed in other physical contexts such as the
Branstator-Kushnir waves in the atmospheric dynamics [1,7].
Chinese: 本文的主要目标是一个研究计划的一部分，旨在将流体流动的动力学与物理空间中的结构和其转变联系起来。作为一个原型问题和为了展示主要思想，我们研究了二维瑞利-贝纳德对流。分析基于两种最近发展的非线性理论：不可压缩流动的几何理论[10]和非线性动力系统的分岔与稳定性理论（有限维和无限维的都包括在内）[9]。我们在[8]中已经证明，当瑞利数R跨越第一个临界瑞利数R_c时，瑞利-贝纳德问题会从基本态分岔到吸引子A_R，这适用于所有物理上合理的边界条件，无论线性问题的R_c特征值的重数如何。在本文中，除了对分岔吸引子A_R的分类之外，还对物理空间中解的结构及其转变进行了分类，从而导致了两种不同流动结构的存在和稳定性：纯滚流和被十字形隔开的通道流。虽然十字形隔开的通道流结构在其他物理背景下（如大气动力学中的Branstator-Kushnir波[1,7]）已被观察到，但似乎还没有得到仔细研究。
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English: The COSINUS direct dark matter experiment situated at Laboratori Nazionali
del Gran Sasso in Italy is set to investigate the nature of the annually
modulating signal detected by the DAMA/LIBRA experiment. COSINUS has already
demonstrated that sodium iodide crystals can be operated at mK temperature as
cryogenic scintillating calorimeters using transition edge sensors, despite the
complication of handling a hygroscopic and low melting point material. With
results from a new COSINUS prototype, we show that particle discrimination on
an event-by-event basis in NaI is feasible using the dual-channel readout of
both phonons and scintillation light. The detector was mounted in the novel
remoTES design and operated in an above-ground facility for 9.06 g$\cdot$d of
exposure. With a 3.7 g NaI crystal, e$^-$/$\gamma$ events could be clearly
distinguished from nuclear recoils down to the nuclear recoil energy threshold
of 15 keV.
Chinese: 意大利格兰萨索国家实验室（Laboratori Nazionali del Gran Sasso）的COSINUS直接暗物质实验计划调查DAMA/LIBRA实验检测到的年度调制信号的特性。COSINUS已经证明，尽管处理具有吸湿性和低熔点的材料存在复杂性，但碘化钠晶体可以在mK温度下作为液氦闪烁量热计使用，并采用过渡边缘传感器进行操作。通过新的COSINUS原型实验结果，我们展示了在NaI中基于事件的事件粒区分是可行的，这通过使用声子和闪烁光的双通道读出实现。探测器被安装在创新的remoTES设计中，并在地面以上的设施中运行了9.06 g·d的曝光时间。使用3.7 g的NaI晶体，e$^-$/$\gamma$事件可以清楚地与核反冲区分开来，直至核反冲能量阈值为15 keV。
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English: e present measurements on $D^0$ meson production via direct reconstruction of
its hadronic decay channel $D^0\to K\pi$ in minimum bias $d$+Au and Au+Au
collisions at $\sqrt{s_{NN}}$=200 GeV with $p_T$ up to $\sim$3 GeV/$c$.
Non-photonic electron spectra from the charm semi-leptonic decays are analyzed
from the same data set as well as in $p$+$p$ collision at $\sqrt{s}$=200 GeV
using the STAR Time-of-Flight (TOF) and Barrel EMC (BEMC) detectors,
respectively. Results of the charm-decayed single muon (prompt muon) spectra
are also presented at low $p_T$ in Au+Au collisions measured by the TOF
detector. The charm production total cross-section per nucleon-nucleon
collision is measured to be 1.26$\pm$0.09(stat.)$\pm$0.23(sys.) mb in minimum
bias Au+Au collisions, which is consistent with the $N_{bin}$ scaling compared
to 1.4$\pm0.2\pm$0.4 mb in minimum bias $d$+Au collisions, and supports the
idea that charm quarks should be produced mostly via parton fusion at early
stage in relativistic heavy-ion collisions. A Blast-Wave model fit to the low
$p_T$ ($<2$ GeV/c) non-photonic electrons, prompt muons and $D^0$ spectra shows
that charm hadrons may kinetically freeze-out earlier than light hadrons with a
smaller collective velocity. The nuclear modification factors ($R_{AA}$) of the
non-photonic electrons in central Au+Au collisions are significantly below
unity at $p_T>\sim$2 GeV/$c$, which indicates a significant amount of energy
loss for heavy quarks in Au+Au collisions. The charm transverse momentum
distribution must have been modified by the hot and dense matter created in
central Au+Au collisions at RHIC.
Chinese: 本文呈现了在 $\sqrt{s_{NN}}$=200 GeV 的 $d$+Au 和 Au+Au 碰撞中，直接通过其强子衰变通道 $D^0\to K\pi$ 重建的 $D^0$ 介子生产的测量结果。非光子电子谱从 $d$+Au 和 Au+Au 碰撞以及 $p$+$p$ 碰撞（$\sqrt{s}$=200 GeV）中通过 $D$ 介子半衰变衰变产生的非光子电子谱也得到了分析，分别使用了 STAR 时间飞行（TOF）和 Barrel EMC（BEMC）探测器。此外，在 Au+Au 碰撞中，使用 TOF 探测器也呈现了由 $D$ 介子衰变产生的单个中子（即提示中子）谱的低 $p_T$ 结果。在最小偏置的 Au+Au 碰撞中，测得的 $D$ 介子衰变产生的单中子（提示中子）谱的总交叉截面为 1.26$\pm$0.09(stat.)$\pm$0.23(sys.) mb，这与 $N_{bin}$ 标度相一致，与最小偏置的 $d$+Au 碰撞中的 1.4$\pm0.2\pm$0.4 mb 相比，支持了在相对论性重离子碰撞中，重夸克主要通过部分子融合在早期阶段产生这一观点。对低 $p_T$（$<2$ GeV/c）的非光子电子、提示中子和 $D^0$ 谱进行 Blast-Wave 模型拟合，显示 $D$ 介子可能在比光子更早的时间点经历动能冻结，具有较小的集体速度。在中央的 Au+Au 碰撞中，非光子电子的核修正因子（$R_{AA}$）在 $p_T>\sim$2 GeV/$c$ 时显著低于 1，这表明在 Au+Au 碰撞中，重夸克经历了显著的能量损失。在中央的 Au+Au 碰撞中，在 RHIC 产生的中央 Au+Au 碰撞中，$D$ 介子的横动量分布必定受到了热和密集物质的影响。
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English: We examine an application of the kernel-based interpolation to numerical
solutions for Zakai equations in nonlinear filtering, and aim to prove its
rigorous convergence. To this end, we find the class of kernels and the
structure of collocation points explicitly under which the process of iterative
interpolation is stable. This result together with standard argument in error
estimation shows that the approximation error is bounded by the order of the
square root of the time step and the error that comes from a single step
interpolation. Our theorem is well consistent with the results of numerical
experiments.
Chinese: 我们考察了基于核的插值在非线性滤波中Zakai方程数值解的一个应用，并旨在证明其严格收敛性。为此，我们明确找到了在迭代插值过程中稳定的核函数类和配置点的结构。这一结果结合误差估计中的标准论证表明，近似误差被时间步长的平方根阶和单步插值产生的误差所限制。我们的定理与数值实验的结果高度一致。
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English: This paper deals with the stabilization of a class of linear
infinite-dimensional systems with unbounded control operators and subject to a
boundary disturbance. We assume that there exists a linear feedback law that
makes the origin of the closed-loop system globally asymptotically stable in
the absence of disturbance. To achieve our objective, we follow a sliding mode
strategy and we add another term to this controller in order to reject the
disturbance. We prove the existence of solutions to the closed-loop system and
its global asymptotic stability, while making sure the disturbance is rejected.
Chinese: 本文讨论了一类具有无界控制算子的线性无穷维系统在边界干扰作用下的稳定化问题。我们假设存在一个线性反馈律，使得闭环系统的原点在没有干扰的情况下全局渐近稳定。为了实现我们的目标，我们采用滑模策略，并在控制器中添加另一个项以拒绝干扰。我们证明了闭环系统的解的存在性及其全局渐近稳定性，同时确保干扰被拒绝。
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English: Brain cognitive functions arise through the coordinated activity of several
brain regions, which actually form complex dynamical systems operating at
multiple frequencies. These systems often consist of interacting subsystems,
whose characterization is of importance for a complete understanding of the
brain interaction processes. To address this issue, we present a technique,
namely the bispectral Pairwise Interacting Source Analysis (biPISA), for
analyzing systems of cross-frequency interacting brain sources when
multichannel electroencephalographic (EEG) or magnetoencephalographic (MEG)
data are available. Specifically, the biPISA allows to identify one or many
subsystems of cross-frequency interacting sources by decomposing the
antisymmetric components of the cross-bispectra between EEG or MEG signals,
based on the assumption that interactions are pairwise. Thanks to the
properties of the antisymmetric components of the cross-bispectra, biPISA is
also robust to spurious interactions arising from mixing artifacts, i.e. volume
conduction or field spread, which always affect EEG or MEG functional
connectivity estimates. This method is an extension of the Pairwise Interacting
Source Analysis (PISA), which was originally introduced for investigating
interactions at the same frequency, to the study of cross-frequency
interactions. The effectiveness of this approach is demonstrated in simulations
for up to three interacting source pairs, and for real MEG recordings of
spontaneous brain activity. Simulations show that the performances of biPISA in
estimating the phase difference between the interacting sources are affected by
the increasing level of noise rather than by the number of the interacting
subsystems. The analysis of real MEG data reveals an interaction between two
pairs of sources of central mu and beta rhythms, localizing in the proximity of
the left and right central sulci.
Chinese: 脑认知功能是通过多个脑区协调活动而产生的，这些脑区实际上形成了在多个频率上运行的复杂动力系统。这些系统通常由相互作用的子系统组成，对这些子系统的特征化对于完全理解脑交互过程至关重要。为了解决这一问题，我们提出了一种技术，即双谱双交互源分析（biPISA），用于在多通道脑电图（EEG）或磁源成像（MEG）数据可用时，分析跨频率交互脑源的系统。具体而言，biPISA 通过基于交互是成对的假设，将跨双谱的反对称分量进行分解，从而能够识别一个或多个跨频率交互源的子系统。得益于跨双谱反对称分量的性质，biPISA 也对来自混合伪影（如体积传导或场扩散）的虚假交互具有鲁棒性，这些伪影总是影响 EEG 或 MEG 功能连接估计。这种方法是 Pairwise 交互源分析（PISA）的扩展，最初引入是为了研究相同频率的交互，现在用于研究跨频率交互。这种方法的有效性在模拟中得到了验证，模拟了最多三个交互源对，并且在自发脑活动的 MEG 记录中进行了实际分析。模拟显示，biPISA 在估计交互源之间的相位差方面的性能受噪声水平的影响，而不是受交互子系统数量的影响。对实际 MEG 数据的分析揭示了中央 mu 和 beta 节律的两个源对之间的交互，定位在左中央沟和右中央沟附近。
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English: We study stochastic mean-field games among finite number of teams with large
finite as well as infinite number of decision makers. For this class of games
within static and dynamic settings, we establish the existence of a Nash
equilibrium, and show that a Nash equilibrium exhibits exchangeability in the
finite decision maker regime and symmetry in the infinite one. To arrive at
these existence and structural theorems, we endow the set of randomized
policies with a suitable topology under various decentralized information
structures, which leads to the desired convexity and compactness of the set of
randomized policies. Then, we establish the existence of a randomized Nash
equilibrium that is exchangeable (not necessarily symmetric) among decision
makers within each team for a general class of exchangeable stochastic games.
As the number of decision makers within each team goes to infinity (that is for
the mean-field game among teams), using a de Finetti representation theorem, we
show existence of a randomized Nash equilibrium that is symmetric (i.e.,
identical) among decision makers within each team and also independently
randomized. Finally, we establish that a Nash equilibrium for a class of
mean-field games among teams (which is symmetric) constitutes an approximate
Nash equilibrium for the corresponding pre-limit (exchangeable) game among
teams with large but finite number of decision makers. We thus show that common
randomness is not necessary for large team-against-team games, unlike the case
with small sized teams.
Chinese: 我们研究了有限数量团队中具有大量有限以及无限决策者的随机均值场博弈。对于这类游戏，在静态和动态环境下，我们建立了纳什均衡的存在性，并表明纳什均衡在有限决策者制度下表现出可交换性，在无限情况下表现出对称性。为了得到这些存在性和结构定理，我们在各种分散信息结构下给随机策略集赋予合适的拓扑结构，这导致了随机策略集所需的凸性和紧致性。然后，我们为一般类可交换随机博弈，建立了在每个团队内决策者之间具有可交换性（不一定是对称性）的随机纳什均衡的存在性。当每个团队内的决策者数量趋于无穷大（即团队间的均值场博弈时），利用de Finetti表示定理，我们证明了在每个团队内决策者之间具有对称性（即相同）且独立随机化的随机纳什均衡的存在性。最后，我们建立了团队间一类均值场博弈（即对称）的纳什均衡构成了对应预极限（可交换）博弈中具有大量但有限决策者的团队之间的近似纳什均衡。因此，我们证明了在大型团队对抗游戏中，与小型团队的情况不同，共同随机性并非必要。
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English: In this work, Pt-Ti core-shell nanoparticles (NP) of 2 nm to 3 nm in size and
30000 u \pm 1500 u as specified single particle mass, deposited on flat silicon
substrates by means of a mass-selected cluster beam source, were used for the
investigation of the modification of the X-Ray Standing Wave (XSW) field
intensity with increasing NP surface coverage. The focus of the investigation
is on the determination of the range of validity of the undisturbed flat
surface approach of the XSW intensity in dependence of the actual coverage rate
of the surface. Therefore, the nanoparticles were characterized using
reference-free grazing incidence X-ray fluorescence analysis (GIXRF) employing
radiometrically calibrated instrumentation. In addition, near-edge X-ray
absorption fine structure (NEXAFS) measurements were performed to investigate
the binding state of titanium in the core-shell nanoparticles which was found
to be amorphous TiO2. The combination of GIXRF measurements and of the
calculated XSW field intensities allow for a quantification of the core-shell
nanoparticle surface coverage. For six different samples, the peak surface
coverage could be determined to vary from 7 % to 130 % of a complete
monolayer-equivalent coverage. A result of the current investigation is that
core-shell nanoparticles modify the intensity distribution of the XSW field
with increasing surface coverage. This experimental result is in line with
calculated XSW field intensity distributions at different surface coverages
using an effective density approach.
Chinese: 在这项工作中，使用了尺寸在2 nm到3 nm之间，指定单粒子质量为30000 u ± 1500 u的Pt-Ti核壳纳米颗粒（NP），通过质量选择的团簇束源沉积在平坦的硅衬底上，用于研究随着NP表面覆盖率的增加，X射线驻波（XSW）场强度的变化。研究的重点是确定XSW强度未受干扰的平坦表面方法的有效范围，这取决于实际的表面覆盖率。因此，使用无参考的掠入射X射线荧光分析（GIXRF）和经辐射计校准的仪器对纳米颗粒进行了表征。此外，还进行了近边缘X射线吸收精细结构（NEXAFS）测量，以研究核壳纳米颗粒中钛的结合状态，发现其为非晶态TiO2。GIXRF测量和计算出的XSW场强度的结合允许对核壳纳米颗粒的表面覆盖率进行量化。对于六个不同的样品，峰值表面覆盖率可以确定为从7%到130%的完整单分子层等效覆盖率。当前研究的结果表明，随着表面覆盖率的增加，核壳纳米颗粒会改变XSW场的强度分布。这一实验结果与使用有效密度方法计算的不同表面覆盖率下的XSW场强度分布相一致。
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