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English: Most deep learning models in medical imaging are trained on adult data with
unclear performance on pediatric images. In this work, we aim to address this
challenge in the context of automated anatomy segmentation in whole-body
Computed Tomography (CT). We evaluate the performance of CT organ segmentation
algorithms trained on adult data when applied to pediatric CT volumes and
identify substantial age-dependent underperformance. We subsequently propose
and evaluate strategies, including data augmentation and continual learning
approaches, to achieve good segmentation accuracy across all age groups. Our
best-performing model, trained using continual learning, achieves high
segmentation accuracy on both adult and pediatric data (Dice scores of 0.90 and
0.84 respectively).
Chinese: 在医学影像中，大多数深度学习模型都是在成人数据上训练的，在儿童影像上的表现并不明确。在本研究中，我们旨在解决全身计算机断层扫描（CT）中自动化解剖分割所面临的这一挑战。我们评估了在成人数据上训练的CT器官分割算法应用于儿童CT体积时的性能，并发现存在显著的年龄依赖性性能不足。随后，我们提出了包括数据增强和持续学习方法在内的策略，以实现对所有年龄组的良好分割精度。我们表现最佳的模型，采用持续学习方法训练，在成人和儿童数据上均实现了高分割精度（Dice分数分别为0.90和0.84）。
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English: For a torsion-free virtually polycyclic group $\Gamma$, we give a canonical
homomorphism form certain finite-dimensional cochain complex to the
$\Q$-polynomial de Rham complex of the simplicial classifying space $B\Gamma$
which induces a cohomology isomorphism. By this result, we obtain the
Sullivan's minimal model of certain differential graded algebra defined on
$B\Gamma$ and we obtain new examples of hard Lefschetz symplectic manifolds and
hard Lefschetz contact manifolds.
Chinese: 对于无挠几乎多项环群$\Gamma$，我们给出一个典型同态，将某个有限维上链复形映射到单形分类空间$B\Gamma$的$\Q$-多项式德·拉姆复形，该同态诱导出上同调同构。通过这一结果，我们得到定义在$B\Gamma$上的某类差分graded代数的苏利文极小模型，并得到新的硬莱夫席茨辛流形和硬莱夫席茨接触流形的例子。
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English: We give an estimate of the gravitational field of force exerted on a test
particle by the far galaxies, in the frame of the weak field approximation. In
virtue of Hubble's law, the action of the far matter turns out to be non
negligible, and even the dominant one. An extremely simplified cosmological
model is considered. A nonvanishing contribution is obtained only if the
discrete and fractal nature of the matter distribution is taken into account.
The force per unit mass acting on a test particle is found to be of the order
of $0.2 cH_0$, where $c$ is the speed of light and $H_0$ the present value of
Hubble's constant.
Chinese: 我们在弱场近似框架下，对远距离星系对测试粒子施加的引力场力进行估算。根据哈勃定律，远距离物质的作用不可忽略，甚至可以说是主导作用。考虑了一个极其简化的宇宙模型。只有当考虑到物质分布的离散和分形性质时，才能获得非零的贡献。对测试粒子作用的单位质量力被发现是 $0.2 cH_0$ 的量级，其中 $c$ 是光速，$H_0$ 是哈勃常数的当前值。
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English: Data assimilation methodologies are designed to incorporate noisy
observations of a physical system into an underlying model in order to infer
the properties of the state of the system. Filters refer to a class of data
assimilation algorithms designed to update the estimation of the state as data
is acquired sequentially. For linear problems subject to Gaussian noise
filtering can be performed exactly using the Kalman filter. For nonlinear
systems it can be approximated in a systematic way by particle filters. However
in high dimensions these particle filtering methods can break down. Hence, for
the large nonlinear systems arising in applications such as oceanography and
weather forecasting, various ad hoc filters are used, based on Gaussian
approximations. In this work, we study the accuracy and stability of these ad
hoc filters in the context of the 2D incompressible Navier-Stokes equation. The
ideas readily generalize to a range of dissipative partial differential
equations (PDEs). By working in this infinite dimensional setting we provide an
analysis which is useful for the understanding of high dimensional filtering,
and is robust to mesh-refinement. We describe theoretical results showing that,
in the small observational noise limit, the filters can be tuned to perform
accurately in tracking the signal itself (filter accuracy), provided the system
is observed in a sufficiently large low dimensional space; roughly speaking
this space should be large enough to contain the unstable modes of the
linearized dynamics. The tuning corresponds to what is known as variance
inflation in the applied literature. Numerical results are given which
illustrate the theory. The positive results herein concerning filter stability
complement recent numerical studies which demonstrate that the ad hoc filters
can perform poorly in reproducing statistical variation about the true signal.
Chinese: 数据同化方法旨在将物理系统的噪声观测值纳入基础模型中，以推断系统状态的属性。滤波器指的是一类数据同化算法，旨在随着数据的逐个获取来更新状态估计。对于受高斯噪声影响的线性问题，可以使用卡尔曼滤波器精确地进行滤波。对于非线性系统，可以通过粒子滤波器以系统化的方式进行近似。然而，在高维情况下，这些粒子滤波方法可能会失效。因此，在海洋学、天气预报等应用中出现的大型非线性系统中，使用各种基于高斯近似的专用滤波器。在本工作中，我们研究了这些专用滤波器在二维不可压缩纳维-斯托克斯方程背景下的准确性和稳定性。这些想法可以轻易地推广到一系列耗散偏微分方程（PDEs）。通过在这个无限维设置中工作，我们提供了一种分析，这对于理解高维滤波是有用的，并且对网格细化具有鲁棒性。我们描述了理论结果，表明在小观测噪声极限下，如果系统在足够大的低维空间中被观察，则滤波器可以被调整以精确跟踪信号本身（滤波器准确度）；简而言之，这个空间应该足够大，以包含线性化动力学的非稳定模式。这种调整对应于应用文献中所称的方差膨胀。给出了数值结果，以说明该理论。关于滤波器稳定性的积极结果补充了最近的数值研究，这些研究表明，专用滤波器在再现关于真实信号的统计变化方面可能表现不佳。
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English: We investigate how the conductance G through a clean interacting quantum wire
is affected by the presence of contacts and noninteracting leads. The contacts
are defined by a vanishing two-particle interaction to the left and a finite
repulsive interaction to the right or vice versa. No additional single-particle
scattering terms (impurities) are added. We first use bosonization and the
local Luttinger liquid picture and show that within this approach G is
determined by the properties of the leads regardless of the details of the
spatial variation of the Luttinger liquid parameters. This generalizes earlier
results obtained for step-like variations. In particular, no single-particle
backscattering is generated at the contacts. We then study a microscopic model
applying the functional renormalization group and show that the spatial
variation of the interaction produces single-particle backscattering, which in
turn leads to a reduced conductance. We investigate how the smoothness of the
contacts affects G and show that for decreasing energy scale its deviation from
the unitary limit follows a power law with the same exponent as obtained for a
system with a weak single-particle impurity placed in the contact region of the
interacting wire and the leads.
Chinese: 我们研究了通过一个干净相互作用的量子导线的电导G如何受到接触和非相互作用引线存在的影响。接触由左侧消失的两粒子相互作用和右侧有限排斥相互作用（或反之）定义。没有添加额外的单粒子散射项（杂质）。我们首先使用玻色化和局部Luttinger液体图像，并表明在这个方法中，G由引线的性质决定，而不管Luttinger液体参数空间变化的细节如何。这推广了之前对于阶梯状变化得到的结果。特别是，在接触处不会产生单粒子反散射。然后我们研究了一个微观模型，应用了功能化重整化群，并表明相互作用的空变产生了单粒子反散射，这反过来又导致电导降低。我们研究了接触的平滑性如何影响G，并表明对于降低的能量尺度，其与单位极限的偏差遵循与在相互作用导线和引线的接触区域放置的弱单粒子杂质系统相同的幂律。
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English: This paper addresses the scheduling problem on two identical parallel
machines with a single server in charge of loading and unloading operations of
jobs. Each job has to be loaded by the server before being processed on one of
the two machines and unloaded by the same server after its processing. No delay
is allowed between loading and processing, and between processing and
unloading. The objective function involves the minimization of the makespan.
This problem referred to as P2, S1|sj , tj |Cmax generalizes the classical
parallel machine scheduling problem with a single server which performs only
the loading (i.e., setup) operation of each job. For this NP-hard problem, no
solution algorithm was proposed in the literature. Therefore, we present two
mixedinteger linear programming (MILP) formulations, one with completion-time
variables along with two valid inequalities and one with time-indexed
variables. In addition, we propose some polynomial-time solvable cases and a
tight theoretical lower bound. In addition, we show that the minimization of
the makespan is equivalent to the minimization of the total idle times on the
machines. To solve large-sized instances of the problem, an efficient General
Variable Neighborhood Search (GVNS) metaheuristic with two mechanisms for
finding an initial solution is designed. The GVNS is evaluated by comparing its
performance with the results provided by the MILPs and another metaheuristic.
The results show that the average percentage deviation from the theoretical
lower-bound of GVNS is within 0.642%. Some managerial insights are presented
and our results are compared with the related literature.
Chinese: 本文研究了在两个相同的并行机器上，由一个服务器负责作业的加载和卸载操作的调度问题。每个作业在处理之前必须由服务器加载到其中一台机器上，处理完毕后由同一服务器卸载。加载和处理之间，以及处理和卸载之间不允许有延迟。目标函数涉及最小化完工时间。这个问题被称为P2，S1|sj，tj|Cmax，它将只有一个服务器执行每个作业的加载（即设置）操作的经典并行机器调度问题进行了推广。对于这个NP难问题，文献中尚未提出解决方案。因此，我们提出了两种混合整数线性规划（MILP）的表述，一种包含完工时间变量以及两个有效不等式，另一种包含时间索引变量。此外，我们提出了一些多项式时间内可解的情况和一个紧的理论下界。此外，我们表明，最小化完工时间等价于最小化机器上的总空闲时间。为了解决该问题的较大规模实例，设计了一种高效的通用变量邻域搜索（GVNS）元启发式算法，该算法具有两种寻找初始解的机制。通过比较其性能与MILP和另一种元启发式算法的结果来评估GVNS。结果表明，GVNS与理论下界的平均百分比偏差在0.642%以内。我们提出了某些管理见解，并将我们的结果与相关文献进行了比较。
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English: We calculate the one loop beta functions for nonlinear sigma models in four
dimensions containing general two and four derivative terms. In the O(N) model
there are four such terms and nontrivial fixed points exist for all N \geq 4.
In the chiral SU(N) models there are in general six couplings, but only five
for N=3 and four for N=2; we find fixed points only for N=2,3. In the
approximation considered, the four derivative couplings are asymptotically free
but the coupling in the two derivative term has a nonzero limit. These results
support the hypothesis that certain sigma models may be asymptotically safe.
Chinese: 我们计算了四维非线性sigma模型的一环β函数，其中包含一般的二阶和四阶导数项。在O(N)模型中，有四个这样的项，并且对于所有N≥4都存在非平凡固定点。在手征SU(N)模型中，通常有六个耦合，但N=3时只有五个，N=2时只有四个；我们只在N=2,3时找到了固定点。在考虑的近似中，四阶导数耦合在渐近上是无耦合的，但二阶导数项的耦合有一个非零极限。这些结果支持了这样的假设：某些sigma模型可能是渐近安全的。
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English: The magnetic phase diagram of the Mn-based semi-Heusler alloys is determined
at T=0 using first-principles calculations in conjunction with the
frozen-magnon approximation. We show that the magnetism in these systems
strongly depends on the number of conduction electrons, their spin polarization
and the position of the unoccupied Mn 3d states with respect to Fermi energy.
Various magnetic phases are obtained depending on these characteristics. The
conditions leading to diverse magnetic behavior are identified. We find that in
the case of a large conduction electron spin polarization and the unoccupied Mn
3d states lying far above the Fermi level, an RKKY-like ferromagnetic
interaction is dominating. On the other hand, the antiferromagnetic
superexchange becomes important in the presence of large peaks of the
unoccupied Mn 3d states lying close to the Fermi energy. The overall magnetic
behavior depends on the competition of these two exchange mechanisms. The
obtained results are in very good agreement with the available experimental
data.
Chinese: 基于Mn的半海瑟勒合金的磁性相图是通过在T=0时结合使用第一性原理计算和冻结磁振子近似确定的。我们表明，这些系统中的磁性强烈依赖于导电电子的数量、它们的自旋极化和未占据的Mn 3d态相对于费米能级的位置。根据这些特征，获得了各种磁性相。确定了导致不同磁性行为的条件。我们发现，在导电电子自旋极化较大且未占据的Mn 3d态远高于费米能级的情况下，RKKY类铁磁性相互作用占主导地位。另一方面，在未占据的Mn 3d态存在较大峰值且靠近费米能级时，反铁磁性超交换变得重要。整体磁性行为取决于这两种交换机制的竞争。获得的结果与现有实验数据非常吻合。
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English: The 7--particle form factors of the fundamental spin field of the O(3)
nonlinear $\sigma$--model are constructed. We calculate the corresponding
contribution to the spin--spin correlation function, and compare with
predictions from the spectral density scaling hypothesis. The resulting
approximation to the spin--spin correlation function agrees well with that
computed in renormalized (asymptotically free) perturbation theory in the
expected energy range. Further we observe simple lower and upper bounds for the
sum of the absolute square of the form factors which may be of use for analytic
estimates.
Chinese: O(3)非线性σ模型的基态自旋场的7粒子形式因子被构造出来。我们计算了对应的自旋-自旋相关函数的贡献，并将其与光谱密度标度假设的预测进行比较。得到的自旋-自旋相关函数的近似值在预期的能量范围内与在重整化（渐近自由）微扰理论中计算的结果相吻合。此外，我们还观察到形式因子绝对平方和的简单下限和上限，这可能在分析估计中有所用途。
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English: Axions provide a solution to the strong CP problem and are excellent dark
matter candidates. The presence of additional sources of CP violation, for
example to account for the matter/antimatter asymmetry of the universe, can
lead to CP-violating interactions between axions and Standard Model fields. In
case axions form a coherent dark matter background, this leads to
time-oscillating fundamental constants such as the fine-structure constant and
particle masses. In this work we compare the sensitivity of various searches
for CP-odd axion interactions. These include fifth-force experiments, searches
for time-oscillating constants induced by axion dark matter, and direct limits
from electric dipole moment experiments. We show that searches for oscillating
constants can outperform fifth-force experiments in the regime of small axion
masses, but, in general, do not reach the sensitivity of electric dipole moment
experiments.
Chinese: 轴子为强CP问题提供了一个解决方案，并且是极好的暗物质候选者。存在额外的CP违反来源，例如为了解释宇宙中物质/反物质的不对称性，可能导致轴子与标准模型场之间的CP违反相互作用。如果轴子形成一个连贯的暗物质背景，这将导致时间振荡的基本常数，如精细结构常数和粒子质量。在这项工作中，我们比较了寻找CP奇偶轴子相互作用的灵敏度。这包括第五力实验、寻找由轴子暗物质引起的振荡常数，以及来自电偶极矩实验的直接限制。我们表明，在轴子质量较小的范围内，寻找振荡常数的灵敏度可以超过第五力实验，但总的来说，并没有达到电偶极矩实验的灵敏度。
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English: There are operations that transform a map M (an embedding of a graph on a
surface) into another map in the same surface, modifying its structure and
consequently its set of flags F(M). For instance, by truncating all the
vertices of a map M, each flag in F(M) is divided into three flags of the
truncated map. Orbanic, Pellicer and Weiss studied the truncation of k-orbit
maps for k < 4. They introduced the notion of T-compatible maps in order to
give a necessary condition for a truncation of a k-orbit map to be either k-,
3k/2- or 3k-orbit map. Using a similar notion, by introducing an appropriate
partition on the set of flags of the maps, we extend the results on truncation
of k-orbit maps for k < 8 and k=9.
Chinese: 存在将地图M（一个在表面上的图嵌入）转换成同一表面上另一个地图的操作，这些操作会改变其结构，从而改变其标志集F(M)。例如，通过截断地图M的所有顶点，F(M)中的每个标志都被分割成截断地图的三个标志。Orbanic、Pellicer和Weiss研究了k-轨道地图的截断问题，其中k < 4。他们引入了T兼容地图的概念，以便为k-轨道地图的截断提供必要条件，使其成为k-、3k/2-或3k-轨道地图。通过引入类似的概念，通过对地图标志集进行适当的划分，我们扩展了关于k < 8和k=9时k-轨道地图截断的结果。
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English: Fermionic ansatz state preparation is a critical subroutine in many quantum
algorithms such as Variational Quantum Eigensolver for quantum chemistry and
condensed matter applications. The shallowest circuit depth needed to prepare
Slater determinants and correlated states to date scale at least linearly with
respect to the system size $N$. Inspired by data-loading circuits developed for
quantum machine learning, we propose an alternate paradigm that provides
shallower, yet scalable ${\mathcal{O}}(d \log_2^2N)$ two-qubit gate depth
circuits to prepare such states with d-fermions, offering a subexponential
reduction in $N$ over existing approaches in second quantization, enabling
high-accuracy studies of $d{\ll}{\mathcal{O}}{\left(N / \log_2^2 N\right)}$
fermionic systems with larger basis sets on near-term quantum devices.
Chinese: 费米子近似态准备是许多量子算法（如量子化学和凝聚态应用中的变分量子能算子）中的关键子程序。迄今为止，准备Slater行列式和相关态所需的最浅电路深度至少与系统大小N成线性关系。受为量子机器学习开发的数据加载电路启发，我们提出了一种替代范式，提供了深度更浅、但可扩展的${\mathcal{O}}(d \log_2^2N)$双量子位门深度电路，用于准备具有d个费米子的此类状态，相对于二次量子化中的现有方法提供了次指数级的N减少，从而能够在近中期量子设备上使用较大的基集对$d{\ll}{\mathcal{O}}{\left(N / \log_2^2 N\right)}$个费米子系统进行高精度研究。
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English: We study nonnegative (psd) real sextic forms $q(x_0,x_1,x_2)$ that are not
sums of squares (sos). Such a form has at most ten real zeros. We give a
complete and explicit characterization of all sets
$S\subset\mathbb{P}^2(\mathbb{R})$ with $|S|=9$ for which there is a psd
non-sos sextic vanishing in $S$. Roughly, on every plane cubic $X$ with only
real nodes there is a certain natural divisor class $\tau_X$ of degree~$9$, and
$S$ is the real zero set of some psd non-sos sextic if, and only if, there is a
unique cubic $X$ through $S$ and $S$ represents the class $\tau_X$ on $X$. If
this is the case, there is a unique extreme ray $\mathbb{R}_+q_S$ of psd
non-sos sextics through $S$, and we show how to find $q_S$ explicitly. The
sextic $q_S$ has a tenth real zero which for generic $S$ does not lie in $S$,
but which may degenerate into a higher singularity contained in $S$. We also
show that for any eight points in $\mathbb{P}^2(\mathbb{R})$ in general
position there exists a psd sextic that is not a sum of squares and vanishes in
the given points.
Chinese: 我们研究非负（正定）实六次形式 $q(x_0,x_1,x_2)$，它们不是平方和（sos）。这种形式最多有十个实零点。我们给出了所有满足 $|S|=9$ 的集合 $S\subset\mathbb{P}^2(\mathbb{R})$ 的完整且明确的特征，这些集合中存在一个正定非sos六次形式在 $S$ 中消失。大致而言，对于只有实节点的每个平面三次曲线 $X$，都存在一个度数为9的特定自然除子类 $\tau_X$，而 $S$ 是某个正定非sos六次形式的实零集，当且仅当存在一条唯一的三次曲线 $X$ 通过 $S$，并且 $S$ 在 $X$ 上代表类 $\tau_X$。在这种情况下，存在唯一的正定非sos六次形式极端射线 $\mathbb{R}_+q_S$ 通过 $S$，我们展示了如何显式地找到 $q_S$。六次形式 $q_S$ 有第十个实零点，对于一般的 $S$，这个零点不在 $S$ 中，但它可能会退化成一个包含在 $S$ 中的更高阶奇点。我们还证明了，对于 $\mathbb{P}^2(\mathbb{R})$ 中任意八个一般位置的点，都存在一个不是平方和的正定六次形式，它在给定点处消失。
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English: We use high-quality, medium-resolution {\it Hubble Space Telescope}/Cosmic
Origins Spectrograph (\HST/COS) observations of 82 UV-bright AGN at redshifts
$z_{AGN}<0.85$ to construct the largest survey of the low-redshift
intergalactic medium (IGM) to date: 5343 individual extragalactic absorption
lines in HI and 25 different metal-ion species grouped into 2610 distinct
redshift systems at $z_{abs}<0.75$ covering total redshift pathlengths $\Delta
z_{HI}=21.7$ and $\Delta z_{OVI}=14.5$. Our semi-automated line-finding and
measurement technique renders the catalog as objectively-defined as possible.
The cumulative column-density distribution of HI systems can be parametrized
$dN(>N)/dz=C_{14}(N/10^{14} cm^{-2})^{-(\beta-1)}$, with $C_{14}=25\pm1$ and
$\beta=1.65\pm0.02$. This distribution is seen to evolve both in amplitude,
$C_{14}\sim(1+z)^{2.0\pm0.1}$, and slope $\beta(z)=1.73-0.26 z$ for $z<0.47$.
We observe metal lines in 427 systems, and find that the fraction of IGM
absorbers detected in metals is strongly dependent on N_{HI}. The distribution
of OVI absorbers appear to evolve in the same sense as the Lya forest. We
calculate contributions to $\Omega_b$ from different components of the low-$z$
IGM and determine the Lya decrement as a function of redshift. IGM absorbers
are analyzed via a two-point correlation function (TPCF) in velocity space. We
find substantial clustering of \HI\ absorbers on scales of $\Delta v=50-300$
km/s with no significant clustering at $\Delta v>1000$ km/s. Splitting the
sample into strong and weak absorbers, we see that most of the clustering
occurs in strong, $N_{HI}>10^{13.5} cm^{-2}$, metal-bearing IGM systems. The
full catalog of absorption lines and fully-reduced spectra is available via
MAST as a high-level science product at http://archive.stsci.edu/prepds/igm/.
Chinese: 我们使用红移 $z_{AGN}<0.85$ 的 82 个紫外明亮类星体的高质量、中等分辨率 {\it Hubble Space Telescope}/Cosmic Origins Spectrograph (\HST/COS) 观测数据，构建了迄今为止最大规模的低红移星际介质 (IGM) 调查：5343 条单独的星系吸收线位于 HI 中，以及 25 种不同的金属离子种类被归入 2610 个不同的红移系统，这些系统在 $z_{abs}<0.75$，覆盖了总红移路径长度 $\Delta z_{HI}=21.7$ 和 $\Delta z_{OVI}=14.5$。我们的半自动化谱线寻找和测量技术使目录尽可能客观地定义。HI 系统的累积柱密度分布可以用 $dN(>N)/dz=C_{14}(N/10^{14} cm^{-2})^{-(\beta-1)}$ 来参数化，其中 $C_{14}=25\pm1$ 和 $\beta=1.65\pm0.02$。这种分布在高幅 $C_{14}\sim(1+z)^{2.0\pm0.1}$ 和斜率 $\beta(z)=1.73-0.26 z$ （对于 $z<0.47$）方面都显示出演化。我们在 427 个系统中观测到金属线，发现金属 IGM 吸收体的比例强烈依赖于 $N_{HI}$。OVI 吸收体的分布似乎与 Lya 森林以相同的方式演化。我们计算了低-$z$ IGM 不同成分对 $\Omega_b$ 的贡献，并确定了 Lya 衰减量作为红移的函数。通过速度空间的二点相关函数 (TPCF) 分析 IGM 吸收体。我们发现 \HI\ 吸收体在 $\Delta v=50-300$ km/s 的尺度上存在显著的团块，而在 $\Delta v>1000$ km/s 时没有显著的团块。将样本分为强吸收体和弱吸收体，我们发现大部分团块发生在强、$N_{HI}>10^{13.5} cm^{-2}$、含有金属的 IGM 系统中。吸收线完整目录和完全精简的光谱可通过 MAST 作为高级科学产品在 http://archive.stsci.edu/prepds/igm/ 获取。
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English: Without any doubt, the relational paradigm has been a huge success. At the
same time, we believe that the time is ripe to rethink how database systems
could look like if we designed them from scratch. Would we really end up with
the same abstractions and techniques that are prevalent today? This paper
explores that space. We discuss the various issues with both the relational
model(RM) and the entity-relationship model (ERM). We provide a unified data
model: the relational map type model (RMTM) which can represent both RM and ERM
as special cases and overcomes all of their problems. We proceed to identify
seven rules that an RMTM query language (QL) must fulfill and provide a
foundation of a language fulfilling all seven rules. Our QL operates on maps
which may represent tuples, relations, databases or sets of databases. Like
that we dramatically expand the existing operational abstractions found in SQL
and relational algebra (RA) which only operate on relations/tables. In fact, RA
is just a special case of our much more generic approach. This work has
far-reaching consequences: we show a path how to come up with a modern QL that
solves (almost if not) all problems of SQL. Our QL is much more expressive than
SQL and integrates smoothly into existing programming languages (PL). We also
show results of an initial experiment showcasing that just by switching to our
data model, and without changing the underlying query processing algorithms, we
can achieve speed-ups of up to a factor 3. We will conclude that, if we build a
database system from scratch, we could and should do this without SQL, RA, RM,
ERM, and ORMs.
Chinese: 毫无疑问，关系范式已经取得了巨大的成功。同时，我们相信是时候重新思考如果我们从头设计数据库系统，它们应该是什么样子了。我们真的会最终得到与今天普遍存在的相同抽象和技巧吗？本文探讨了这一领域。我们讨论了关系模型（RM）和实体关系模型（ERM）的各种问题。我们提供了一个统一的数据模型：关系映射类型模型（RMTM），它可以表示RM和ERM作为特例，并克服了它们的所有问题。我们进一步确定了RMTM查询语言（QL）必须满足的七条规则，并提供了一个满足所有七条规则的语言的基礎。我们的QL操作映射，这些映射可以表示元组、关系、数据库或数据库集。通过这种方式，我们极大地扩展了SQL和关系代数（RA）中发现的现有操作抽象，后者仅操作关系/表。事实上，RA只是我们更通用方法的特例。这项工作具有深远的影响：我们展示了一条路径，说明如何开发一种现代QL，它可以解决（几乎如果非全部）SQL的所有问题。我们的QL比SQL更具表达能力，并能顺畅地集成到现有的编程语言（PL）中。我们还展示了初步实验的结果，展示了仅切换到我们的数据模型，而不改变底层的查询处理算法，我们就可以实现高达3倍的加速。我们将得出结论，如果我们从头构建数据库系统，我们能够也应该不依赖SQL、RA、RM、ERM和ORM来完成。
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English: The noncommutative spacetimes associated to the $\kappa$-Poincar\'e
relativistic symmetries and their "non-relativistic" (Galilei) and
"ultra-relativistic" (Carroll) limits are indistinguishable, since their
coordinates satisfy the same algebra. In this work, we show that the three
quantum kinematical models can be differentiated when looking at the associated
spaces of time-like worldlines. Specifically, we construct the noncommutative
spaces of time-like geodesics with $\kappa$-Galilei and $\kappa$-Carroll
symmetries as contractions of the corresponding $\kappa$-Poincar\'e space and
we show that these three spaces are defined by different algebras. In
particular, the $\kappa$-Galilei space of worldlines resembles the so-called
Euclidean Snyder model, while the $\kappa$-Carroll space turns out to be
commutative. Furthermore, we identify the map between quantum spaces of
geodesics and the corresponding noncommutative spacetimes, which requires to
extend the space of geodesics by adding the noncommutative time coordinate.
Chinese: 与 $\kappa$-Poincaré 相对性对称相关的不交换时空及其“非相对论性”（伽利略）和“超相对论性”（卡罗尔）极限是无法区分的，因为它们的坐标满足相同的代数。在这项工作中，我们表明，在观察相关的时间线空间时，三个量子动力学模型是可以区分的。具体来说，我们构建了具有 $\kappa$-伽利略和 $\kappa$-卡罗尔对称性的类时测地线的不交换空间，并表明这三个空间由不同的代数定义。特别是，世界线的 $\kappa$-伽利略空间类似于所谓的欧几里得斯奈德模型，而 $\kappa$-卡罗尔空间实际上是交换的。此外，我们还确定了测地线量子空间与相应的非交换时空之间的映射，这需要通过添加非交换的时间坐标来扩展测地线空间。
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English: Gravitational lensing allows us to probe the structure of matter on a broad
range of astronomical scales, and as light from a distant source traverses an
intervening galaxy, compact matter such as planets, stars, and black holes act
as individual lenses. The magnification from such microlensing results in rapid
brightness fluctuations which reveal not only the properties of the lensing
masses, but also the surface brightness distribution in the source. However,
while the combination of deflections due to individual stars is linear, the
resulting magnifications are highly non-linear, leading to significant
computational challenges which currently limit the range of problems which can
be tackled. This paper presents a new and novel implementation of a numerical
approach to gravitational microlensing, increasing the scale of the problems
that can be tackled by more than two orders of magnitude, opening up a new
regime of astrophysically interesting problems.
Chinese: 引力透镜效应使我们能够探测不同天文尺度上的物质结构，当来自遥远天体的光穿越一个介于其间的星系时，行星、恒星和黑洞等致密物质充当单个透镜。这种微透镜效应的放大导致亮度快速变化，不仅揭示了透镜质量属性，还揭示了源表面的亮度分布。然而，尽管由于单个恒星引起的偏转是线性的，但由此产生的放大却是高度非线性的，这导致了重大的计算挑战，目前限制了可以解决的问题范围。本文提出了一种新的数值方法，用于引力微透镜效应，将可解决的问题规模提高了两个数量级以上，开辟了新的天体物理问题领域。
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English: Hexapeptides are increasingly applied as model systems for studying the
amyloidogenecity properties of oligo- and polypeptides. It is possible to
construct 64 million different hexapeptides from the twenty proteinogenic amino
acid residues. Today's experimental amyloid databases contain only a fraction
of these annotated hexapeptides. For labeling all the possible hexapeptides as
"amyloidogenic" or "non-amyloidogenic" there exist several computational
predictors with good accuracies. It may be of interest to define and study a
simple graph structure on the 64 million hexapeptides as nodes when two
hexapeptides are connected by an edge if they differ by only a single residue.
For example, in this graph, HIKKLM is connected to AIKKLM, or HIKKNM, or
HIKKLC, but it is not connected with an edge to VVKKLM or HIKNPM. In the
present contribution, we consider our previously published artificial
intelligence-based tool, the Budapest Amyloid Predictor (BAP for short), and
demonstrate a spectacular property of this predictor in the graph defined
above. We show that for any two hexapeptides predicted to be "amyloidogenic" by
the BAP predictor, there exists an easily constructible path of length at most
6 that passes through neighboring hexapeptides all predicted to be
"amyloidogenic" by BAP. For example, the predicted amyloidogenic ILVWIW and
FWLCYL hexapeptides can be connected through the length-6 path
ILVWIW-IWVWIW-IWVCIW-IWVCIL-FWVCIL-FWLCIL-FWLCYL in such a way that the
neighbors differ in exactly one residue, and all hexapeptides on the path are
predicted to be amyloidogenic by BAP. The symmetric statement also holds for
non-amyloidogenic hexapeptides. It is noted that the mentioned property of the
Budapest Amyloid Predictor \url{https://pitgroup.org/bap} is not proprietary;
it is also true for any linear Support Vector Machine (SVM)-based predictors.
Chinese: 六肽越来越多地被用作研究寡聚和多肽的淀粉样变性倾向性的模型系统。从二十种蛋白生成氨基酸残基中，可以构建出6400万种不同的六肽。今天的实验性淀粉样数据库只包含了这些注释六肽的一小部分。为了将所有可能的六肽标记为“淀粉样变性倾向性”或“非淀粉样变性倾向性”，存在多个具有良好准确性的计算预测器。定义并研究6400万六肽作为节点，当两个六肽仅在一个氨基酸残基上不同时，它们之间通过一条边相连的简单图结构可能是有趣的。例如，在这个图中，HIKKLM与AIKKLM、HIKKNM或HIKKLC相连，但与VVKKLM或HIKNPM之间没有边相连。在本贡献中，我们考虑了我们之前发表的人工智能工具，布达佩斯淀粉样预测器（BAP，简称），并展示了该预测器在上述定义的图中所具有的引人注目的性质。我们证明，对于任何两个由BAP预测器预测为“淀粉样变性倾向性”的六肽，都存在一条长度不超过6的路径，该路径经过BAP预测为“淀粉样变性倾向性”的所有相邻六肽。例如，预测的淀粉样变性倾向性ILVWIW和FWLCYL六肽可以通过长度为6的路径ILVWIW-IWVWIW-IWVCIW-IWVCIL-FWVCIL-FWLCIL-FWLCYL连接，使得相邻六肽在恰好一个氨基酸残基上不同，并且路径上的所有六肽均由BAP预测为淀粉样变性倾向性。对于非淀粉样变性倾向性六肽，对称的陈述也成立。值得注意的是，提到的布达佩斯淀粉样预测器的性质不是专有的；对于任何线性支持向量机（SVM）预测器也是正确的。
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English: A finite tree $T$ with $|V(T)| \geq 2$ is called {\it automorphism-free} if
there is no non-trivial automorphism of $T$. Let $\mathcal{AFT}$ be the poset
with the element set of all finite automorphism-free trees (up to graph
isomorphism) ordered by $T_1 \preceq T_2$ if $T_1$ can be obtained from $T_2$
by successively deleting one leaf at a time in such a way that each
intermediate tree is also automorphism-free. In this paper, we prove that
$\mathcal{AFT}$ has a unique minimal element. This result gives an affirmative
answer to the question asked by Rupinski.
Chinese: 一个有限树$T$，且$|V(T)| \geq 2$，若不存在非平凡的$T$的自同构，则称其为{\it 自同构自由的}。设$\mathcal{AFT}$为所有有限自同构自由树（在图同构意义下）的元素集构成的偏序集，其按$T_1 \preceq T_2$排序，当且仅当$T_1$可以通过逐个删除一个叶子节点从$T_2$得到，且每一步得到的中间树仍保持自同构自由。本文证明了$\mathcal{AFT}$具有唯一的极小元。这一结果对Rupinski提出的问题给出了肯定回答。
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English: Large language models (LLMs) have been utilized in solving diverse reasoning
tasks, encompassing common sense, arithmetic and deduction tasks. However, with
difficulties of reversing thinking patterns and irrelevant premises, how to
determine the authenticity of the cause in abductive logical reasoning remains
underexplored. Inspired by hypothesis and verification method and
identification of irrelevant information in human thinking process, we propose
a new framework for LLMs abductive logical reasoning called CauseJudger (CJ),
which identifies the authenticity of possible cause by transforming thinking
from reverse to forward and removing irrelevant information. In addition, we
construct an abductive logical reasoning dataset for decision task called
CauseLogics, which contains 200,000 tasks of varying reasoning lengths. Our
experiments show the efficiency of CJ with overall experiments and ablation
experiments as well as case studies on our dataset and reconstructed public
dataset. Notably, CJ's implementation is efficient, requiring only two calls to
LLM. Its impact is profound: when using gpt-3.5, CJ achieves a maximum
correctness improvement of 41% compared to Zero-Shot-CoT. Moreover, with gpt-4,
CJ attains an accuracy exceeding 90% across all datasets.
Chinese: 大型语言模型（LLMs）已被用于解决各种推理任务，包括常识、算术和演绎任务。然而，由于难以逆转思维模式和不相关前提的困难，如何确定归纳逻辑推理中原因的真实性仍然没有得到充分探索。受假设和验证方法以及人类思维过程中识别不相关信息灵感的启发，我们提出了一种新的LLMs归纳逻辑推理框架，称为CauseJudger（CJ），通过将思维从逆向转变为正向并去除不相关信息来识别可能原因的真实性。此外，我们构建了一个用于决策任务的归纳逻辑推理数据集，称为CauseLogics，包含200,000个不同推理长度的任务。我们的实验显示了CJ的效率，包括整体实验、消融实验以及在我们数据集和重构的公共数据集上的案例研究。值得注意的是，CJ的实现效率高，只需调用LLM两次。其影响深远：在使用gpt-3.5时，与Zero-Shot-CoT相比，CJ实现了41%的最大正确性提升。此外，使用gpt-4时，CJ在所有数据集上达到了超过90%的准确率。
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English: We present a status report on the study of gamma-ray bursts (GRB) in the era
of rapid follow-up using the world's largest robotic optical telescopes - the
2-m Liverpool and Faulkes telescopes. Within the context of key unsolved issues
in GRB physics, we describe (1) our innovative software that allows real-time
automatic analysis and interpretation of GRB light curves, (2) the novel
instrumentation that allows unique types of observations (in particular, early
time polarisation measurements) and (3) the key science questions and
discoveries to which robotic observations are ideally suited, concluding with a
summary of current understanding of GRB physics provided by combining rapid
optical observations with simultaneous observations at other wavelengths.
Chinese: 我们报告了在快速后续观测时代，利用世界上最大的机器人光学望远镜——2米利物浦和福尔克斯望远镜——对伽马射线暴（GRB）的研究进展。在GRB物理学中的关键未解决问题背景下，我们描述了以下内容：（1）我们创新的软件，它允许对GRB光曲线进行实时自动分析和解释；（2）新型仪器，它允许进行独特的观测类型（特别是早期时间极化测量）；（3）机器人观测最适合的关键科学问题和发现，最后总结了通过结合快速光学观测与其他波长的同步观测所提供的当前对GRB物理学的理解。
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English: We relate the canonical basis of the Fock space representation of the quantum
affine algebra $U_q(\widehat{\mathfrak{gl}}_{n})$, as defined by Leclerc and
Thibon, to the canonical basis of its restriction to $U_q(\mathfrak{sl}_{n})$,
regarded as a based module in the sense of Lusztig. More generally we consider
the restriction to any parabolic subalgebra. We deduce results on decomposition
numbers and branching coefficients of Schur algebras over fields of positive
characteristic, generalising those of Kleshchev and of Tan and Teo.
Chinese: 我们将Leclerc和Thibon定义的量子仿射代数$U_q(\widehat{\mathfrak{gl}}_{n})$的Fock空间表示的典型基，与其限制到$U_q(\mathfrak{sl}_{n})$的典型基联系起来，后者在Lusztig的意义下被视为一个基于模块。更一般地，我们考虑限制到任何斜对称子代数。我们推导出关于正特征场上的Schur代数分解数和分支系数的结果，这些结果推广了Kleshchev以及Tan和Teo的结果。
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English: We study the transients of linear max-plus dynamical systems. For that, we
consider for each irreducible max-plus matrix A, the weighted graph G(A) such
that A is the adjacency matrix of G(A). Based on a novel graph-theoretic
counterpart to the number-theoretic Brauer's theorem, we propose two new
methods for the construction of arbitrarily long paths in G(A) with maximal
weight. That leads to two new upper bounds on the transient of a linear
max-plus system which both improve on the bounds previously given by Even and
Rajsbaum (STOC 1990, Theory of Computing Systems 1997), by Bouillard and Gaujal
(Research Report 2000), and by Soto y Koelemeijer (PhD Thesis 2003), and are,
in general, incomparable with Hartmann and Arguelles' bound (Mathematics of
Operations Research 1999). With our approach, we also show how to improve the
latter bound by a factor of two.
A significant benefit of our bounds is that each of them turns out to be
linear in the size of the system in various classes of linear max-plus system
whereas the bounds previously given are all at least quadratic. Our second
result concerns the relationship between matrix and system transients: We prove
that the transient of an NxN matrix A is, up to some constant, equal to the
transient of an A-linear system with an initial vector whose norm is quadratic
in N. Finally, we study the applicability of our results to the well-known Full
Reversal algorithm whose behavior can be described as a min-plus linear system.
Chinese: 我们研究线性最大加动态系统的瞬态。为此，我们考虑对于每个不可约的最大加矩阵A，定义加权图G(A)，使得A是G(A)的邻接矩阵。基于一个新颖的图论对应于数论中的Brauer定理，我们提出了两种在G(A)中构造任意长路径的新方法，这些路径具有最大权重。这导致了线性最大加系统瞬态的两个新的上界，这两个上界都优于Even和Rajsbaum（STOC 1990，理论计算系统1997）、Bouillard和Gaujal（研究报告2000）以及Soto y Koelemeijer（博士论文2003）之前给出的界限，并且通常与Hartmann和Arguelles的界限（运筹学数学1999）不可比。使用我们的方法，我们还展示了如何将后者界限提高两倍。
我们界限的一个显著优点是，在许多线性最大加系统的类别中，每个界限都最终是系统规模的线性函数，而之前给出的界限都是至少二次的。我们的第二个结果涉及矩阵和系统瞬态之间的关系：我们证明，一个NxN矩阵A的瞬态，在某个常数范围内，等于一个A-线性系统的瞬态，该系统的初始向量的范数是N的二次函数。最后，我们研究了我们的结果对著名的完全反转算法的适用性，该算法的行为可以用最小加线性系统来描述。
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English: Recent advancements in artificial intelligence (AI) have precipitated
significant breakthroughs in healthcare, particularly in refining diagnostic
procedures. However, previous studies have often been constrained to limited
functionalities. This study introduces MiniGPT-Med, a vision-language model
derived from large-scale language models and tailored for medical applications.
MiniGPT-Med demonstrates remarkable versatility across various imaging
modalities, including X-rays, CT scans, and MRIs, enhancing its utility. The
model is capable of performing tasks such as medical report generation, visual
question answering (VQA), and disease identification within medical imagery.
Its integrated processing of both image and textual clinical data markedly
improves diagnostic accuracy. Our empirical assessments confirm MiniGPT-Med's
superior performance in disease grounding, medical report generation, and VQA
benchmarks, representing a significant step towards reducing the gap in
assisting radiology practice. Furthermore, it achieves state-of-the-art
performance on medical report generation, higher than the previous best model
by 19\% accuracy. MiniGPT-Med promises to become a general interface for
radiology diagnoses, enhancing diagnostic efficiency across a wide range of
medical imaging applications.
Chinese: 近年来人工智能（AI）的快速发展在医疗领域带来了重大突破，尤其是在诊断流程的优化上。然而，以往研究往往受限于功能范围。本研究引入了MiniGPT-Med，这是一种基于大规模语言模型并专为医疗应用定制的视觉语言模型。MiniGPT-Med在X光片、CT扫描和MRI等多种影像模态上展现出卓越的通用性，显著提升了其应用价值。该模型能够执行医疗报告生成、视觉问答（VQA）和疾病识别等任务，通过整合图像和文本临床数据的联合处理，显著提高了诊断准确率。我们的实证评估证实，MiniGPT-Med在疾病关联定位、医疗报告生成和VQA基准测试中表现优异，为缩小辅助放射科实践差距迈出了重要一步。此外，它在医疗报告生成任务上达到当前最佳水平，准确率比前代模型高出19%。MiniGPT-Med有望成为放射科诊断的通用接口，在广泛的医学影像应用中提升诊断效率。
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English: Competition between independently arising beneficial mutations is enhanced in
spatial populations due to the linear rather than exponential growth of clones.
Recent theoretical studies have pointed out that the resulting fitness dynamics
is analogous to a surface growth process, where new layers nucleate and spread
stochastically, leading to the build up of scale-invariant roughness. This
scenario differs qualitatively from the standard view of adaptation in that the
speed of adaptation becomes independent of population size while the fitness
variance does not. Here we exploit recent progress in the understanding of
surface growth processes to obtain precise predictions for the universal,
non-Gaussian shape of the fitness distribution for one-dimensional habitats,
which are verified by simulations. When the mutations are deleterious rather
than beneficial the problem becomes a spatial version of Muller's ratchet. In
contrast to the case of well-mixed populations, the rate of fitness decline
remains finite even in the limit of an infinite habitat, provided the ratio
$U_d/s^2$ between the deleterious mutation rate and the square of the
(negative) selection coefficient is sufficiently large. Using again an analogy
to surface growth models we show that the transition between the stationary and
the moving state of the ratchet is governed by directed percolation.
Chinese: 由于克隆的线性增长而非指数增长，空间种群中独立出现的有益突变之间的竞争得到增强。最近的理论研究表明，由此产生的适应性动态类似于表面生长过程，其中新的层随机成核并扩散，导致尺度不变粗糙度的积累。这种情景在定性上与适应性标准的观点不同，因为适应速度变得与种群大小无关，而适应性方差则不然。在这里，我们利用对表面生长过程理解的最新进展，获得了关于一维栖息地中适应性分布的普遍、非高斯形状的精确预测，这一预测通过模拟得到了验证。当突变是有害的而不是有益的时，问题变成了穆勒轮的空間版本。与充分混合的种群的情况相反，即使在无限栖息地的极限情况下，只要有害突变率与（负）选择系数平方之间的比率 $U_d/s^2$ 足够大，适应性下降的速率仍然有限。再次使用表面生长模型的类比，我们表明穆勒轮的静态和动态状态之间的转变由有向渗流控制。
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English: An automorphism $f$ of a closed orientable surface $\Sigma$ is said to be
extendable over the 3-sphere $S^3$ if $f$ extends to an automorphism of the
pair $(S^3, \Sigma)$ with respect to some embedding $\Sigma \hookrightarrow
S^3$. We prove that if an automorphism of a genus-2 surface $\Sigma$ is
extendable over $S^3$, then $f$ extends to an automorphism of the pair $(S^3,
\Sigma)$ with respect to an embedding $\Sigma \hookrightarrow S^3$ such that
$\Sigma$ bounds genus-2 handlebodies on both sides. The classification of
essential annuli in the exterior of genus-2 handlebodies embedded in $S^3$ due
to Ozawa and the second author plays a key role.
Chinese: 我们称闭取向表面$\Sigma$上的同构$f$在3维球面$S^3$上可延展，如果$f$可以扩展为关于某个嵌入$\Sigma \hookrightarrow S^3$的$(S^3, \Sigma)$对的同构。我们证明，如果一个曲率为2的表面$\Sigma$上的同构$f$在$S^3$上可延展，那么$f$可以扩展为关于某个嵌入$\Sigma \hookrightarrow S^3$的$(S^3, \Sigma)$对的同构，其中$\Sigma$在两侧都与曲率为2的柄体边界。Ozawa和第二作者关于嵌入在$S^3$中的曲率为2的柄体外部的必要环面的分类起着关键作用。
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English: In general, the field equations of $f(R)$ theory coupled to a matter field
are very complicated and hence it is not easy to find exact analytical
solutions. However, if one considers traceless energy-momentum tensor for the
matter source as well as constant scalar curvature, one can derive some exact
analytical solutions from $f(R)$ theory coupled to a matter field. In this
paper, by assuming constant curvature scalar, we construct a class of charged
rotating black string solutions in $f(R)$-Maxwell theory. We study the physical
properties and obtain the conserved quantities of the solutions. The conserved
and thermodynamic quantities computed here depend on function $f'(R_{0})$ and
differ completely from those of Einstein theory in AdS spaces. Besides, unlike
Einstein gravity, the entropy does not obey the area law. We also investigate
the validity of the first law of thermodynamics as well as the stability
analysis in the canonical ensemble, and show that the black string solutions
are always thermodynamically stable in $f(R)$-Maxwell theory with constant
curvature scalar. Finally, we extend the study to the case where the Ricci
scalar is not a constant and in particular $R=R(r)$. In this case, by using the
Lagrangian multipliers method, we derive an analytical black string solution
from $f(R)$ gravity and reconstructed the function $R(r)$. We find that this
class of solutions has an additional logaritmic term in the metric function
which incorporates the effect of the $f(R)$ theory in the solutions.
Chinese: 一般来说，$f(R)$理论中与物质场耦合的场方程非常复杂，因此找到精确的解析解并不容易。然而，如果考虑物质源的迹为零的能量动量张量以及常标量曲率，可以从与物质场耦合的$f(R)$理论中导出一些精确的解析解。在本论文中，假设标量曲率为常数，我们构造了一类在$f(R)$-Maxwell理论中的带电旋转黑洞弦解。我们研究了这些解的物理性质，并得到了解的守恒量。这里计算得到的守恒和热力学量依赖于函数$f'(R_{0})$，与AdS空间中的爱因斯坦理论完全不同。此外，与爱因斯坦引力不同，熵不遵循面积定律。我们还研究了第一热力学定律的有效性以及规范系下的稳定性分析，并表明在$f(R)$-Maxwell理论中具有常标量曲率的带电旋转黑洞弦解始终是热力学稳定的。最后，我们扩展研究到Ricci标量不是常数的情况，特别是$R=R(r)$。在这种情况下，通过拉格朗日乘数法，我们从$f(R)$引力中导出了一个解析的黑洞弦解，并重构了函数$R(r)$。我们发现，这一类解在度规函数中有一个额外的对数项，它包含了$f(R)$理论在解中的影响。
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English: Post-selection, the power of discarding all runs of a computation in which an
undesirable event occurs, is an influential concept introduced to the field of
quantum complexity theory by Aaronson (Proceedings of the Royal Society A,
2005). In the present paper, we initiate the study of post-selection for
space-bounded quantum complexity classes. Our main result shows the identity
$\sf PostBQL=PL$, i.e., the class of problems that can be solved by a
bounded-error (polynomial-time) logarithmic-space quantum algorithm with
post-selection ($\sf PostBQL$) is equal to the class of problems that can be
solved by unbounded-error logarithmic-space classical algorithms ($\sf PL$).
This result gives a space-bounded version of the well-known result $\sf
PostBQP=PP$ proved by Aaronson for polynomial-time quantum computation. As a
by-product, we also show that $\sf PL$ coincides with the class of problems
that can be solved by bounded-error logarithmic-space quantum algorithms that
have no time bound.
Chinese: 在筛选之后，能够丢弃所有计算中出现不良事件的所有运行的能力，是一个由Aaronson（皇家学会A辑，2005年）引入量子复杂度理论领域的重要概念。在本文中，我们开始研究空间受限的量子复杂度类中的筛选。我们的主要结果展示了等式 $\sf PostBQL=PL$，即，能够被具有筛选的（有界误差的、多项式时间的）对数空间量子算法解决的问题的类（$\sf PostBQL$）等于能够被无界误差对数空间经典算法解决的问题的类（$\sf PL$）。这一结果给出了Aaronson为多项式时间量子计算证明的著名结果 $\sf PostBQP=PP$ 的空间受限版本。作为副产品，我们还证明了 $\sf PL$ 与能够被无时间限制的有界误差对数空间量子算法解决的问题的类相一致。
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English: Minor mergers of galaxies are expected to be common in a hierarchical
cosmology such as $\Lambda$CDM and have the potential to significantly affect
galactic structure. In this paper we dissect the case-by-case outcome from a
set of numerical simulations of a single satellite elliptical galaxy accreting
onto a massive elliptical galaxy. We take care to explore cosmologically
relevant orbital parameters and to set up realistic initial galaxy models that
include all three relevant dynamical components: dark matter halos, stellar
bulges, and central massive black holes. The effects of several different
parameters are considered, including orbital energy and angular momentum,
satellite density and inner density profile, satellite-to-host mass ratio, and
presence of a black hole at the center of the host. Black holes play a crucial
role in protecting the shallow stellar cores of the hosts, as satellites
merging onto a host with a central black hole are more strongly disrupted than
those merging onto hosts without black holes. Orbital parameters play an
important role in determining the degree of disruption: satellites on less
bound or more eccentric orbits are more easily destroyed than those on more
bound or more circular orbits as a result of an increased number of pericentric
passages and greater cumulative effects of gravitational shocking and tidal
stripping. In addition, satellites with densities typical of faint elliptical
galaxies are disrupted relatively easily, while denser satellites can survive
much better in the tidal field of the host. Over the range of parameters
explored, we find that the accretion of a single satellite elliptical galaxy
can result in a broad variety of changes, in both signs, in the surface
brightness profile and color of the central part of an elliptical galaxy.
Chinese: 在像$\Lambda$CDM这样的层次宇宙学中，星系的小规模并合预计很常见，并且有可能显著影响星系结构。在本文中，我们通过一组数值模拟来剖析单个卫星椭圆星系并合到大型椭圆星系上的个案结果。我们仔细研究了与宇宙学相关的轨道参数，并建立了包含所有三个相关动力学成分（暗物质晕、恒星核和中心超大质量黑洞）的现实初始星系模型。我们考虑了多种不同参数的影响，包括轨道能量和角动量、卫星密度和内部密度分布、卫星与主星系的质量比，以及主星系中心是否存在黑洞。黑洞在保护主星系浅层恒星核方面起着关键作用，因为并合到有中心黑洞的主星系的卫星比并合到没有黑洞的主星系的卫星更容易被破坏。轨道参数在决定破坏程度方面起着重要作用：处于束缚较弱或更偏心轨道上的卫星比处于束缚更强或更圆形轨道上的卫星更容易被破坏，这是由于近心点经过次数增加以及引力冲击和潮汐剥离的累积效应更大。此外，密度具有暗椭圆星系典型特征的卫星相对容易被破坏，而密度更高的卫星能在主星系的潮汐场中生存得更好。在所研究的参数范围内，我们发现单个卫星椭圆星系的并合会导致椭圆星系中心部分的表面亮度分布和颜色发生广泛的变化，包括正负两种情况。
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English: We reveal that classical light diffraction in arrays of specially modulated
coupled optical waveguides can simulate the quantum process of two-mode
squeezing in nonlinear media, with the waveguide mode amplitudes corresponding
the signal and idler photon numbers. The whole Fock space is mapped by a set of
arrays, where each array represents the states with a fixed difference between
the signal and idler photon numbers. We demonstrate a critical transition from
photon number growth to Bloch oscillations with periodical revivals of an
arbitrary input state, associated with an increase of the effective phase
mismatch between the pump and the squeezed photons.
Chinese: 我们揭示，在特别调制的耦合光学波导阵列中，经典光衍射可以模拟非线性介质中的两模压缩量子过程，其中波导模式振幅对应于信号光和闲光子数。整个福克空间通过一组阵列映射，其中每个阵列代表信号光和闲光子数固定差值的态。我们演示了一个关键转变，从光子数增长到周期性振荡的布洛赫振荡，伴随着任意输入态的周期性再生，这与泵浦光和压缩光子之间的有效相位失配增加有关。
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English: Quantum supermaps provide a framework in which higher order quantum processes
can act on lower order quantum processes. In doing so, they enable the
definition and analysis of new quantum protocols and causal structures.
Recently, key features of quantum supermaps were captured through a general
categorical framework, which led to a framework of higher order process
theories (HOPT). The HOPT framework models lower and higher order
transformations in a single unified theory, with its mathematical structure
shown to coincide with the notion of a closed symmetric monoidal category. Here
we provide an equivalent construction of the HOPT framework from four simple
axioms of process-theoretic nature. We then use the HOPT framework to establish
connections between foundational features such as causality, determinism and
signalling, alongside exploring their interaction with the mathematical
structure of *-autonomy.
Chinese: 量子超映射提供了一个框架，使高阶量子过程能够作用于低阶量子过程。通过这种方式，它们使得新量子协议和因果结构的定义与分析成为可能。最近，通过一个通用的范畴框架，量子超映射的关键特征被揭示，这促成了高阶过程理论（HOPT）框架的建立。HOPT框架将低阶和高阶变换统一在一个理论中，其数学结构被证明与闭对称单调范畴的概念相吻合。在此，我们从四个过程理论性质的简单公理出发，给出了HOPT框架的等价构造。然后，我们使用HOPT框架建立因果性、决定论和信号传递等基础特征之间的联系，同时探索它们与*-自洽数学结构的相互作用。
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English: We summarize the physics motivations for future accelerators at CERN. We
argue that (a) a luminosity upgrade for the LHC could provide good physics
return for a relatively modest capital investment, (b) CLIC would provide
excellent long-term perspectives within many speculative scenarios for physics
beyond the Standard Model, (c) a Very Large Hadron Collider could provide the
first opportunity to explore the energy range up to about 30 TeV, (d) a
neutrino factory based on a muon storage ring would provide an exciting and
complementary scientific programme and a muon collider could be an interesting
later option.
Chinese: 我们总结了CERN未来加速器的物理动机。我们论证了以下观点：(a) 对LHC进行亮度升级可以在相对适度的资本投资下获得良好的物理回报；(b) CLIC将在许多关于超越标准模型的物理学的推测性场景中提供良好的长期前景；(c) 一个超大型强子对撞机将提供探索高达约30TeV能量范围的第一机会；(d) 基于μ子储存环的中微子工厂将提供一个激动人心的补充科学计划，而μ子对撞机可能是一个有趣的后备选择。
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English: We present a tight extremal threshold for the existence of Hamilton cycles in
graphs with large minimum degree and without a large ``bipartite hole`` (two
disjoint sets of vertices with no edges between them). This result extends
Dirac's classical theorem, and is related to a theorem of Chv\'atal and
Erd\H{o}s.
In detail, an $(s, t)$-bipartite-hole in a graph $G$ consists of two disjoint
sets of vertices $S$ and $T$ with $|S|= s$ and $|T|=t$ such that there are no
edges between $S$ and $T$; and $\widetilde{\alpha}(G)$ is the maximum integer
$r$ such that $G$ contains an $(s, t)$-bipartite-hole for every pair of
non-negative integers $s$ and $t$ with $s + t = r$. Our central theorem is that
a graph $G$ with at least $3$ vertices is Hamiltonian if its minimum degree is
at least $\widetilde{\alpha}(G)$.
From the proof we obtain a polynomial time algorithm that either finds a
Hamilton cycle or a large bipartite hole. The theorem also yields a condition
for the existence of $k$ edge-disjoint Hamilton cycles. We see that for dense
random graphs $G(n,p)$, the probability of failing to contain many
edge-disjoint Hamilton cycles is $(1 - p)^{(1 + o(1))n}$. Finally, we discuss
the complexity of calculating and approximating $\widetilde{\alpha}(G)$.
Chinese: 我们提出了一种紧致极值阈值，用于判断在具有大最小度且没有大“二分洞”的图中是否存在哈密顿回路（没有边的两个不相交顶点集）。这一结果扩展了Dirac的经典定理，并与Chvátal和Erdős的一个定理相关。
具体来说，图G中的$(s, t)$-二分洞由两个不相交的顶点集$S$和$T$组成，其中$|S|= s$和$|T|=t$，且$S$和$T$之间没有边；而$\widetilde{\alpha}(G)$是满足对于每一对非负整数$s$和$t$，使得$s + t = r$时，$G$都包含一个$(s, t)$-二分洞的最大整数$r$。我们的中心定理是，如果一个图$G$至少有3个顶点，并且其最小度数至少为$\widetilde{\alpha}(G)$，则$G$是哈密顿图。
从证明中，我们得到了一个多项式时间算法，该算法要么找到一个哈密顿回路，要么找到一个大的二分洞。该定理还给出了一种存在$k$条边不交哈密顿回路的条件。我们观察到，对于密集随机图$G(n,p)$，不包含许多边不交哈密顿回路的概率是$(1 - p)^{(1 + o(1))n}$。最后，我们讨论了计算和近似$\widetilde{\alpha}(G)$的复杂性。
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English: We describe some numerical experiments which determine the degree of spectral
instability of medium size randomly generated matrices which are far from
self-adjoint. The conclusion is that the eigenvalues are likely to be
intrinsically uncomputable for similar matrices of a larger size. We also
describe a stochastic family of bounded operators in infinite dimensions for
almost all of which the eigenvectors generate a dense linear subspace, but the
eigenvalues do not determine the spectrum. Our results imply that the spectrum
of the non-self-adjoint Anderson model changes suddenly as one passes to the
infinite volume limit.
Chinese: 我们描述了一些数值实验，这些实验确定了远离自伴性的中等大小随机生成矩阵的谱不稳定性程度。结论是，对于更大尺寸的类似矩阵，特征值可能本质上是不可计算的。我们还描述了一个在无限维中具有有界算子的随机族，对于其中绝大多数，特征向量生成一个稠密的线性子空间，但特征值并不决定谱。我们的结果表明，非自伴安德森模型的谱在通过无限体积极限时会发生突然变化。
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English: Recently, the quantification of errors in the stochastic homogenization of
divergence-form operators has witnessed important progress. Our aim now is to
go beyond error bounds, and give precise descriptions of the effect of the
randomness, in the large-scale limit. This paper is a first step in this
direction. Our main result is to identify the correlation structure of the
corrector, in dimension $3$ and higher. This correlation structure is similar
to, but different from that of a Gaussian free field.
Chinese: 最近，在散射型收敛算子误差量化方面取得了重要进展。我们的目标是超越误差界限，并给出随机性在大尺度极限下的精确描述。本文是朝这个方向迈出的第一步。我们的主要结果是确定在三维及更高维度的修正器的相关结构。这种相关结构类似于，但不同于高斯自由场的相关结构。
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English: We extract pairing gap in $^{184}$W at finite temperature for the first time
from the experimental level densities of $^{183}$W, $^{184}$W, and $^{185}$W
using "thermal" odd-even mass difference. We found the quenching of pairing gap
near the critical temperature $T_c = 0.47$ MeV in the BCS calculations. It is
shown that the monopole pairing model with a deformed Woods-Saxon potential
explains the reduction of the pairing correlation using the partition function
with the number parity projection in the static path approximation plus
random-phase approximation.
Chinese: 我们首次利用"热"奇偶质量差，从$^{183}$W、$^{184}$W和$^{185}$W的实验能级密度中提取了有限温度下的$^{184}$W配对能隙。我们在BCS计算中发现，在临界温度$T_c = 0.47$ MeV附近配对能隙存在淬灭现象。研究表明，采用变形伍德-萨克斯势的单极配对模型，通过静态路径近似加随机相位近似的配分函数（含宇数宇称投影），能够解释配对关联的减弱。
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English: We introduce S1-Bench, a novel benchmark designed to evaluate Large Reasoning
Models' (LRMs) performance on simple tasks that favor intuitive system 1
thinking rather than deliberative system 2 reasoning. While LRMs have achieved
significant breakthroughs in complex reasoning tasks through explicit chains of
thought, their reliance on deep analytical thinking may limit their system 1
thinking capabilities. Moreover, a lack of benchmark currently exists to
evaluate LRMs' performance in tasks that require such capabilities. To fill
this gap, S1-Bench presents a set of simple, diverse, and naturally clear
questions across multiple domains and languages, specifically designed to
assess LRMs' performance in such tasks. Our comprehensive evaluation of 22 LRMs
reveals significant lower efficiency tendencies, with outputs averaging 15.5
times longer than those of traditional small LLMs. Additionally, LRMs often
identify correct answers early but continue unnecessary deliberation, with some
models even producing numerous errors. These findings highlight the rigid
reasoning patterns of current LRMs and underscore the substantial development
needed to achieve balanced dual-system thinking capabilities that can adapt
appropriately to task complexity.
Chinese: 我们引入了S1-Bench，这是一个新的基准，旨在评估大型推理模型（LRMs）在简单任务上的性能，这些任务更倾向于直觉性系统1思维，而不是深思熟虑的系统2推理。虽然LRMs通过明确的思维链条在复杂推理任务上取得了显著的突破，但它们对深度分析思维的依赖可能会限制它们的系统1思维能力。此外，目前尚缺乏基准来评估LRMs在需要这种能力任务上的性能。为了填补这一空白，S1-Bench提出了一组简单、多样且自然清晰的跨多个领域和语言的问答，专门设计来评估LRMs在这些任务上的性能。我们对22个LRMs的全面评估揭示了显著的低效率倾向，其输出平均比传统小型LLMs长15.5倍。此外，LRMs通常能早期识别正确答案，但会继续不必要的深思熟虑，一些模型甚至会产生众多错误。这些发现突出了当前LRMs僵化的推理模式，并强调了实现能够适应任务复杂性的平衡的双系统思维能力所必需的大量发展。
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English: We use supersymmetric localization to study probes of four dimensional
Lagrangian N=2 superconformal field theories. We first derive a unique equation
for the eigenvalue density of these theories. We observe that these theories
have a Wigner eigenvalue density precisely when they satisfy a necessary
condition for having a holographic dual with a sensible higher-derivative
expansion. We then compute in the saddle-point approximation the vacuum
expectation value of 1/2-BPS circular Wilson loops, and the two-point functions
of these Wilson loops with the Lagrangian density and with the stress-energy
tensor. This last computation also provides the corresponding Bremsstrahlung
functions and entanglement entropies. As expected, whenever a finite fraction
of the matter is in the fundamental representation, the results are drastically
different from those of N=4 supersymmetric Yang-Mills theory.
Chinese: 我们使用超对称定位来研究四维拉格朗日N=2超共形场论探针。我们首先推导出这些理论的特征值密度的唯一方程。我们观察到，当这些理论满足具有合理的高阶导数展开的 holographic dual 的必要条件时，它们具有 Wigner 特征值密度。然后，我们在鞍点近似下计算了 1/2-BPS 圆形 Wilson 环的真空期望值，以及这些 Wilson 环与拉格朗日密度以及应力能张量的双点函数。这一最后的计算还提供了相应的 Bremsstrahlung 函数和纠缠熵。正如预期的那样，当有限比例的物质处于基本表示时，结果与 N=4 超对称 Yang-Mills 理论的结果截然不同。
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English: This paper undertakes an empirical study to revisit the latest advancements
in Multimodal Large Language Models (MLLMs): Video Assistant. This study,
namely FreeVA, aims to extend existing image-based MLLM to the video domain in
a training-free manner. The study provides an essential, yet must-know
baseline, and reveals several surprising findings: 1) FreeVA, leveraging only
offline image-based MLLM without additional training, excels in zero-shot video
question-answering (e.g., MSVD-QA, ActivityNet-QA, and MSRVTT-QA), even
surpassing state-of-the-art methods that involve video instruction tuning. 2)
While mainstream video-based MLLMs typically initialize with an image-based
MLLM (e.g., LLaVA) and then fine-tune using video instruction tuning, the study
indicates that utilizing the widely adopted VideoInstruct-100K for video
instruction tuning doesn't actually lead to better performance compared to not
training at all. 3) The commonly used evaluation metrics in existing works are
significantly influenced by changes in the GPT API version over time. If
ignored, this could affect the fairness and uniformity of comparisons between
different methods and impact the analysis and judgment of researchers in the
field. The advancement of MLLMs is currently thriving, drawing numerous
researchers into the field. We aim for this work to serve as a plug-and-play,
simple yet effective baseline, encouraging the direct evaluation of existing
MLLMs in video domain while also standardizing the field of video
conversational models to a certain extent. Also, we encourage researchers to
reconsider: Have current video MLLM methods truly acquired knowledge beyond
image MLLM? Code is available at https://github.com/whwu95/FreeVA
Chinese: 本文进行了一项实证研究，旨在回顾多模态大型语言模型（MLLMs）的最新进展：视频助手。这项研究，即FreeVA，旨在以无需训练的方式将现有的基于图像的MLLM扩展到视频领域。该研究提供了一个基本且必须了解的基线，并揭示了几个令人惊讶的发现：1）FreeVA仅利用离线基于图像的MLLM（无需额外训练），在零样本视频问答（例如，MSVD-QA、ActivityNet-QA和MSRVTT-QA）方面表现出色，甚至超过了涉及视频指令调整的最先进方法。2）尽管主流基于视频的MLLMs通常以基于图像的MLLM（例如，LLaVA）初始化，然后使用视频指令调整进行微调，但研究表明，使用广泛采用的VideoInstruct-100K进行视频指令调整实际上并不比完全不训练有更好的性能。3）现有工作中常用的评估指标受到GPT API版本随时间变化的影响很大。如果忽略这一点，可能会影响不同方法之间比较的公平性和一致性，并影响该领域研究人员对分析和判断的影响。MLLMs的进步目前正蓬勃发展，吸引了众多研究人员进入该领域。我们希望这项工作能够作为即插即用的、简单而有效的基线，鼓励直接评估现有MLLMs在视频领域中的应用，并在一定程度上标准化视频对话模型领域。此外，我们鼓励研究人员重新考虑：当前的基于视频的MLLM方法是否真正获得了超越图像MLLM的知识？代码可在https://github.com/whwu95/FreeVA获取。
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English: Non-Markovian quantum evolution of the electronic subsystem in a laser-driven
molecule is characterized through the appearance of negative decoherence rates
in the canonical form of the electronic master equation. For a driven molecular
system described in a bipartite Hilbert space H=Hel x Hvib of dimension 2 x Nv,
we derive the canonical form of the electronic master equation, deducing the
canonical measures of non-Markovianity and the Bloch volume of accessible
states. We find that one of the decoherence rates is always negative,
accounting for the inherent non-Markovian character of the electronic evolution
in the vibrational environment. Enhanced non-Markovian behavior, characterized
by two negative decoherence rates, appears if there is a coupling between the
electronic states g, e, such that the evolution of the electronic populations
obeys d(PgPe)/dt > 0. Non-Markovianity of the electronic evolution is analyzed
in relation to temporal behaviors of the electronic-vibrational entanglement
and electronic coherence, showing that enhanced non-Markovian behavior
accompanies entanglement increase. Taking as an example the coupling of two
electronic states by a laser pulse in the Cs2 molecule, we analyze
non-Markovian dynamics under laser pulses of various strengths, finding that
the weaker pulse stimulates the bigger amount of non-Markovianity. We show that
increase of the electronic-vibrational entanglement over a time interval is
correlated to the growth of the total amount of non-Markovianity calculated
over the same interval using canonical measures and connected with the increase
of the Bloch volume. After the pulse, non-Markovian behavior is correlated to
electronic coherence, such that vibrational motion in the electronic potentials
which diminishes the nuclear overlap, implicitly increasing the linear entropy
of entanglement, brings a memory character to dynamics.
Chinese: 非马尔可夫量子演化在激光驱动分子中电子子系统的表征，通过电子主方程的标准形式中出现负的退相干率来体现。在一个用二维的希尔斯伯特空间H=Hel x Hvib描述的驱动分子系统中，我们推导了电子主方程的标准形式，从中得出非马尔可夫特性的标准度量和可访问状态的布洛赫体积。我们发现其中一个退相干率总是负的，这代表了电子在振动环境中的内在非马尔可夫特性。当电子态g和e之间存在耦合，使得电子种群演化的速率满足d(PgPe)/dt > 0时，会表现出由两个负退相干率表征的增强的非马尔可夫行为。电子演化的非马尔可夫性，通过电子-振动纠缠和电子相干性的时间行为进行分析，表明增强的非马尔可夫行为伴随着纠缠的增加。以Cs2分子中激光脉冲耦合两个电子态为例，我们分析了不同强度激光脉冲下的非马尔可夫动力学，发现较弱的脉冲会刺激更大的非马尔可夫性。我们展示了在一定时间间隔内电子-振动纠缠的增加与该时间间隔内使用标准度量计算的总非马尔可夫性增长之间存在相关性，这与布洛赫体积的增加相关。脉冲之后，非马尔可夫行为与电子相干性相关，即在电子势能中振动运动，减少核重叠，隐含地增加纠缠的线性熵，给动力学带来了记忆特性。
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English: The physical and chemical properties of metal nanoparticles differ
significantly from those of free metal atoms as well as from the properties of
bulk metals, and therefore, they may be viewed as a transition regime between
the two physical states. Within this nanosize regime, there is a wide
fluctuation of properties, particularly chemical reactivity, as a function of
the size, geometry, and electronic state of the metal nanoparticles. In recent
years, great advancements have been made in the attempts to control and
manipulate the growth of metal particles to pre-specified dimensions. One of
the main synthetic methods utilized in this endeavor, is the capping of the
growing clusters with a variety of molecules, e.g. polymers. In this paper we
attempt to model such a process and show the relationship between the
concentration of the polymer present in the system and the final metal particle
size obtained. The theoretical behavior which we obtained is compared with
experimental results for the cobalt-polystyrene system.
Chinese: 金属纳米粒子的物理和化学性质与自由金属原子以及块状金属的性质显著不同，因此，它们可以被视为两种物理状态之间的过渡区域。在这个纳米尺寸区域，性质存在广泛的波动，尤其是化学活性，这取决于金属纳米粒子的尺寸、几何形状和电子状态。近年来，在尝试控制并操纵金属粒子的生长以达到预定的尺寸方面取得了重大进展。在此过程中，所使用的主要合成方法之一是使用各种分子，例如聚合物，对生长的团簇进行封端。在本文中，我们试图模拟这样一个过程，并展示系统中存在的聚合物浓度与最终获得的金属粒子尺寸之间的关系。我们获得的理论行为与钴-聚苯乙烯系统的实验结果进行了比较。
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English: In this work, we have considered the entropy-corrected new agegraphic dark
energy (ECNADE) model in Horava-Lifshitz gravity in FRW universe. We have
discussed the correspondence between ECNADE and other dark energy models such
as DBI-essence,Yang-Mills dark energy, Chameleon field, Non-linear
electrodynamics field and hessence dark energy in the context of
Horava-Lifshitz gravity and reconstructed the potentials and the dynamics of
the scalar field theory which describe the ECNADE.
Chinese: 在这项工作中，我们考虑了在FRW宇宙中Horava-Lifshitz引力下的熵校正新年龄图暗能量（ECNADE）模型。我们讨论了ECNADE与其他暗能量模型之间的对应关系，例如DBI-本质、Yang-Mills暗能量、Chameleon场、非线性电动力学场和hessence暗能量，在Horava-Lifshitz引力的背景下，并重建了描述ECNADE的标量场理论的势和动力学。
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English: We propose a new architecture for adapting a sentence-level
sequence-to-sequence transformer by incorporating multiple pretrained document
context signals and assess the impact on translation performance of (1)
different pretraining approaches for generating these signals, (2) the quantity
of parallel data for which document context is available, and (3) conditioning
on source, target, or source and target contexts. Experiments on the NIST
Chinese-English, and IWSLT and WMT English-German tasks support four general
conclusions: that using pretrained context representations markedly improves
sample efficiency, that adequate parallel data resources are crucial for
learning to use document context, that jointly conditioning on multiple context
representations outperforms any single representation, and that source context
is more valuable for translation performance than target side context. Our best
multi-context model consistently outperforms the best existing context-aware
transformers.
Chinese: 我们提出了一种新的架构，用于通过整合多个预训练文档上下文信号来适应句子级别的序列到序列变换器，并评估了以下因素对翻译性能的影响：(1) 生成这些信号的不同预训练方法，(2) 文档上下文可用的平行数据量，以及(3) 基于源、目标或源和目标上下文的条件。在NIST中文-英文、IWSLT和WMT英语-德语任务上的实验支持四个一般性结论：使用预训练的上下文表示显著提高了样本效率，充足的平行数据资源对于学习使用文档上下文至关重要，同时条件于多个上下文表示的性能优于任何单一表示，以及源上下文对翻译性能比目标侧上下文更有价值。我们的最佳多上下文模型始终优于现有的最佳上下文感知变换器。
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English: Space provides unique opportunities to test gravitation. By using an
interplanetary spacecraft as a test mass, it is possible to test General
Relativity at the Solar System distance scale. This requires to compute
accurately the trajectory of the spacecraft, a process which relies on radio
tracking and is limited by the uncertainty on the spacecraft non-gravitational
acceleration.
The Gravity Advanced Package (GAP) is designed to measure the
non-gravitational acceleration without bias. It is composed of an electrostatic
accelerometer supplemented by a rotating stage. This article presents the
instrument and its performances, and describes the method to make unbiased
measurements. Finally, it addresses briefly the improvement brought by the
instrument as far as orbit reconstruction is concerned.
Chinese: 空间为检验引力提供了独特的机会。通过将星际飞船作为检验质量，可以在太阳系距离尺度上检验广义相对论。这需要精确计算飞船的轨道，该过程依赖于无线电跟踪，并受限于飞船非引力加速度的不确定性。
引力高级包（GAP）旨在无偏置地测量非引力加速度。它由一个静电加速计和一个旋转平台组成。本文介绍了该仪器及其性能，并描述了进行无偏置测量的方法。最后，简要说明了该仪器在轨道重建方面带来的改进。
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English: The global-in-time existence of nonnegative bounded weak solutions to a class
of cross-diffusion systems for two population species is proved. The
diffusivities are assumed to depend linearly on the population densities in
such a way that a certain formal gradient-flow structure holds. The main
feature of these systems is that the diffusion matrix may be neither symmetric
nor positive definite. The key idea of the proof is to employ the
boundedness-by-entropy principle which yields at the same time the existence of
global weak solutions and their boundedness. In particular, the uniform
boundedness of weak solutions to the population model of Shigesada, Kawasaki,
and Teramoto in several space dimensions under certain conditions on the
diffusivities is shown for the first time.
Chinese: 证明了对于两种种群物种的交叉扩散系统，非负有界弱解在全局时间上的存在性。假设扩散率线性依赖于种群密度，从而保持某种形式上的梯度流结构。这些系统的主要特点是扩散矩阵可能既不对称也不正定。证明的关键思想是采用熵原理的界限，这同时保证了全局弱解的存在性和它们的界限。特别是，在扩散率满足某些条件下，首次展示了Shigesada、Kawasaki和Teramoto种群模型在多个空间维度上弱解的一致有界性。
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English: We show that properly detuning the carrier frequency of each of the
criss-cross bichromatic waves from the transition frequency of the atom, it is
possible to form a two-dimensional trap for atoms if the intensity of the waves
is sufficiently large. For zero and near zero initial phases of waves, and also
for $\pi$ and near $\pi$ phase shift between criss-cross waves a dynamic
spatial structure of square cells with the side $\lambda /\sqrt{2}$ is formed.
Numerical simulations are carried out for sodium atoms.
Chinese: 我们表明，将交叉双频波的载波频率适当地从原子的跃迁频率调谐，如果波强度足够大，则可以形成二维原子陷阱。对于波动的初始相位为零和接近零，以及交叉波之间的相位差为π和接近π，形成边长为λ/√2的正方形细胞动态空间结构。对钠原子进行了数值模拟。
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English: We show that a bijection $f:\mathbb{H}^2\rightarrow\mathbb{H}^2$ of the
hyperbolic plane that sends horocycles to horocycles (respectively hypercycles
to hypercycles) is an isometry. This extends a previous result of J. Jeffers on
geodesics to all curves with constant curvature in $\mathbb{H}^2$. We go beyond
by showing that every abstract automorphism of the geodesic graph (respectively
horocycles and hypercycles graphs) is induced by an earthquake map
(respectively an isometry) of $\mathbb{H}^2$. This shadowed the difference
between the geometry of geodesics and that of horocycles/hypercycles.
Chinese: 我们证明了双曲平面 $\mathbb{H}^2$ 上的一个双射 $f:\mathbb{H}^2\rightarrow\mathbb{H}^2$，它将双曲周期映射到双曲周期（分别将超周期映射到超周期），是一个等距映射。这一结果扩展了 J. Jeffers 关于测地线的先前研究结果，将其应用于 $\mathbb{H}^2$ 中所有具有常曲率的曲线。我们更进一步，证明了测地线图（分别双曲周期图和超周期图）的每个抽象自同构都是由 $\mathbb{H}^2$ 的地震映射（分别等距映射）诱导的。这掩盖了测地线几何与双曲周期/超周期几何之间的差异。
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English: Adiabatic transformation can be approximated as alternating unitary operators
of a Hamiltonian and its parameter derivative as proposed in a gate-based
approach to counterdiabatic driving (van Vreumingen, arXiv:2406.08064). In this
paper, we conduct numerical benchmarking of this alternating unitary method in
a finite-parameter range against adiabatic driving in nonadiabatic timescale.
We find that the alternating unitary method results in broader distribution on
energy eigenstates than that obtained by adiabatic driving, but it has ability
to sample low-energy eigenstates when an energy gap of a given Hamiltonian is
small. It indicates that the alternating unitary method may be able to find
good approximate solutions in quantum annealing applied to hard instances.
Chinese: 绝热变换可以近似为哈密顿量及其参数导数的交替酉算子，正如基于门的方法提出用于反绝热驱动时所建议的那样（van Vreumingen, arXiv:2406.08064）。在本文中，我们在有限参数范围内对这种交替酉方法进行数值基准测试，以与非绝热时间尺度下的绝热驱动进行对比。我们发现，交替酉方法得到的能量本征态分布比绝热驱动得到的更宽，但当给定哈密顿量的能隙较小时，该方法仍具有采样低能本征态的能力。这表明，交替酉方法可能在应用于困难实例的量子退火中找到良好的近似解。
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English: Steady state simulations} of magnetized electron fluid equations with strong
anisotropic diffusion based on the first-order hyperbolic approach is carried
out using cell-centered higher order upwind schemes, linear and weighted
essentially non-oscillatory (WENO). Along with the magnetized electrons, the
diffusion equation is also simulated to demonstrate the implementation and
design order of the accuracy of the approach due to their similar upwind
structure. We show the adequacy of linear upwind schemes for diffusion equation
and the use of shock-capturing scheme like WENO does not have any adverse
effect on the solution, unlike the total-variation diminishing (TVD) methods.
We further extended the approach to advection-diffusion equation, and
appropriate boundary conditions have obtained a consistent design accuracy of
the third and fifth order. We implemented the WENO approach to
advection-diffusion equation by using the split hyperbolic method to
demonstrate the advantage of non-oscillatory schemes to capture sharp gradients
in boundary layer type problems without spurious oscillations. Finally,
numerical results for magnetized electrons simulations indicate that with
increasing strength of magnetic confinement it is possible to capture sharp
gradients without oscillations by WENO scheme.
Chinese: 对磁化电子流体方程组进行了稳态模拟，基于一阶双曲型方法，使用中心差分的高阶迎风方案，线性与加权非振荡（WENO）。除了磁化电子外，还模拟了扩散方程，以展示该方法实现和设计精度的准确性，因为它们具有相似的迎风结构。我们证明了线性迎风方案对扩散方程的适用性，以及使用如WENO这样的冲击捕获方案不会对解产生任何不利影响，与总变差缩减（TVD）方法不同。我们进一步将方法扩展到对流-扩散方程，并得到了一致设计精度的第三和第五阶的适当边界条件。我们使用分割双曲型方法将WENO方法应用于对流-扩散方程，以展示非振荡方案在边界层类型问题中捕捉尖锐梯度而不产生虚假振荡的优势。最后，磁化电子模拟的数值结果表明，随着磁约束强度的增加，WENO方案可以捕捉到尖锐的梯度而不产生振荡。
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English: Congestions in wireless sensor networks (WSNs) could potentially cause packet
loss, throughput impairment and energy waste. To address this issue, a
hop-by-hop cross-layer congestion control scheme (HCCC) built on
contention-based MAC protocol is proposed in this paper. According to MAC-layer
channel information including buffer occupancy ratio and congestion degree of
local node, HCCC dynamically adjusts channel access priority in MAC layer and
data transmission rate of the node to tackle the problem of congestion.
Simulations have been conducted to compare HCCC against closely-related
existing schemes. The results show that HCCC exhibits considerable superiority
in terms of packets loss ratio, throughput and energy efficiency.
Chinese: 无线传感器网络（WSNs）中的拥塞可能会造成数据包丢失、吞吐量下降和能源浪费。为了解决这个问题，本文提出了一种基于争用式MAC协议的逐跳跨层拥塞控制方案（HCCC）。根据MAC层信道信息，包括本地节点的缓冲区占用比和拥塞程度，HCCC动态调整MAC层的信道访问优先级和节点的数据传输速率，以解决拥塞问题。已经进行了仿真实验，以比较HCCC与现有相关方案的优劣。结果表明，在数据包丢失率、吞吐量和能源效率方面，HCCC表现出显著的优势。
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English: We examine the effect of a Hard Brexit on Irish Exports using the PPML
Gravity Model and Irish Exports data at the micro level. We find a hard Brexit
could reduce Irish national income by over 9 billion euro annually and the
effect would be sustained mst in th etraditional sectors of Agriculture and
Food production of the Irish economy
Chinese: 我们使用PPML重力模型和爱尔兰出口的微观层面数据，来考察“硬脱欧”对爱尔兰出口的影响。我们发现，硬脱欧可能会使爱尔兰国民收入每年减少超过90亿欧元，并且这种影响主要会在爱尔兰经济中传统的农业和食品生产部门持续存在。
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English: Boundary S matrices for the boundary tricritical Ising field theory (TIM),
both with and without supersymmetry, have previously been proposed. Here we
provide support for these S matrices by showing that the corresponding boundary
entropies are consistent with the expected boundary flows. We develop the
fusion procedure for boundary RSOS models, with which we derive exact inversion
identities for the TIM. We confirm the TBA description of nonsupersymmetric
boundary flows of Lesage et al., and we obtain corresponding descriptions of
supersymmetric boundary flows.
Chinese: 边界三临界伊辛场论（TIM）的边界S矩阵，无论是带有还是不带超对称性，之前都已经提出。在这里，我们通过表明相应的边界熵与预期的边界流一致，为这些S矩阵提供支持。我们开发了边界RSOS模型的融合过程，通过这个过程，我们推导出TIM的精确逆恒等式。我们确认了Lesage等人关于非超对称边界流的TBA描述，并获得了相应的超对称边界流的描述。
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English: Photonic accelerators have recently attracted soaring interest, harnessing
the ultimate nature of light for information processing. Collective
decision-making with a laser network, employing the chaotic and synchronous
dynamics of optically interconnected lasers to address the competitive
multi-armed bandit (CMAB) problem, is a highly compelling approach due to its
scalability and experimental feasibility. We investigated essential network
structures for collective decision-making through quantitative stability
analysis. Moreover, we demonstrated the asymmetric preferences of players in
the CMAB problem, extending its functionality to more practical applications.
Our study highlights the capability and significance of machine learning built
upon chaotic lasers and photonic devices.
Chinese: 光子加速器最近引起了极大的兴趣，它利用光的本质特性进行信息处理。利用激光网络进行集体决策，通过利用光学互联激光的混沌和同步动力学来解决竞争多臂老虎机（CMAB）问题，这是一种极具吸引力的方法，因为它具有可扩展性和实验可行性。我们通过定量稳定性分析研究了集体决策的关键网络结构。此外，我们展示了CMAB问题中玩家的非对称偏好，扩展了其功能以应用于更实际的应用。我们的研究突出了基于混沌激光和光子设备的机器学习的能力和重要性。
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English: By means of finite size exact diagonalization we theoretically study the
electronic many-body effects on the nearly flat-band structure with
time-reversal symmetry in a checkerboard lattice model and identify the
topological nature of two quantum phases, with ninefold and threefold
degeneracy, that appear, respectively, at small and large values $\lambda$ of a
nearest neighbor spin dependent interaction. Numerical evidences from the
evolution of low-lying energy spectra and Berry phases with both
spin-independent and spin-dependent twisted boundary conditions reveal that
these two different ground states share the same topological spin Chern number.
Quantum phase transition between these two states by tuning $\lambda$ is
confirmed by evaluating the energy spectra and quasispin excitation spectra
closing. At last, the counting rules of spin excitation spectra are
demonstrated as the fingerprints of the fractionalized quantum spin Hall
states.
Chinese: 通过有限大小精确对角化方法，我们理论上研究了具有时间反演对称性的棋盘格模型中，近平坦能带结构上的电子多体效应，并确定了在最近邻自旋相关相互作用的小值和大值 $\lambda$ 处分别出现的具有九重和三重简并的两个量子相的空间拓扑性质。来自低能级能谱和具有自旋无关和自旋相关扭曲边界条件的Berry相演化的数值证据表明，这两种不同的基态具有相同的拓扑自旋Chern数。通过调节 $\lambda$ 来实现这两个状态之间的量子相变，通过评估能量谱和准自旋激发谱的闭合来证实。最后，证明了自旋激发谱的计数规则是分数化量子自旋霍尔态的指纹。
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English: In this work, we present the formation and characterization of a quaternary
(pseudo ternary) icosahedral quasicrystal in Al65Ga5Pd17Mn13 alloy. The X ray
diffraction and transmission electron microscopy confirmed the formation of
icosahedral B2 type and O crystalline (orthorhombic structure) phases in as
cast alloy. The icosahedral phase gets formed after annealing at 800 C for 60
hours. The formation of icosahedral phase in AlGaPdMn quaternary alloy by
present technique has been studied for the first time. The Energy dispersive
X-ray analysis investigations suggest the presence of Ga (5 at) in the alloy.
It is interesting to note that pseudo twelve fold pattern in the as cast alloy
has been observed. Icosahedral AlGaPdMn provides a new opportunity to
investigate the various characteristics including surface characteristics.
Attempts will be made to discuss the micromechanisms for the formation of
quasicrystalline phase in Al-Ga-Pd-Mn alloys.
Chinese: 在这项工作中，我们展示了Al65Ga5Pd17Mn13合金中四元（准三元）二十面体准晶的形成和表征。X射线衍射和透射电子显微镜证实了在铸态合金中形成了二十面体B2型相和O晶体（正交结构）相。二十面体相在800℃退火60小时后形成。首次研究了通过现有技术制备AlGaPdMn四元合金中二十面体相的形成。能量色散X射线分析研究表明合金中存在Ga（5原子百分比）。值得注意的是，在铸态合金中观察到了准十二重图案。二十面体AlGaPdMn为研究包括表面特性在内的各种特性提供了新的机会。将尝试讨论Al-Ga-Pd-Mn合金中准晶相形成的微观机制。
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English: We develop a hydrodynamic description for the driven-dissipative dynamics of
the entanglement negativity, which quantifies the genuine entanglement in
mixed-state systems. We focus on quantum quenches in fermionic and bosonic
systems subject to linear dissipation, as described by quadratic Lindblad
master equations. In the spirit of hydrodynamics, we divide the system into
mesoscopic cells. At early times, correlations are generated in each cell by
the unitary component of the evolution. Correlations are then transported
across different cells via ballistic quasiparticle propagation, while
simultaneously evolving under the action of the environment. We show that in
the hydrodynamic limit the negativity can be reconstructed from the
correlations between the independently propagating quasiparticles. We benchmark
our approach considering quenches from both homogeneous and inhomogeneous
initial states in the Kitaev chain, the tight-binding chain, and the harmonic
chain in the presence of gain/loss dissipation.
Chinese: 我们针对纠缠负值的驱动耗散动力学，发展了一种流体动力学描述，该描述量化了混合态系统中的真实纠缠。我们关注受线性耗散影响的费米子和玻色子系统中的量子淬灭，这些系统由二次 Lindblad 主方程描述。在流体动力学的精神下，我们将系统划分为介观单元。在早期，每个单元中由演化的幺正部分产生关联。随后，关联通过弹道准粒子传播在不同单元之间传输，同时在外界的作用下演化。我们表明，在流体动力学极限下，可以通过独立传播的准粒子之间的关联重建负值。我们通过考虑在增益/损耗耗散存在下，Kitaev 链、紧束缚链和简谐链中从均匀和非均匀初始态开始的淬灭，来验证我们的方法。
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English: The young star V1331 Cyg received previous attention because it is surrounded
by an optical, arc-like reflection nebula. V1331 Cyg is commonly considered to
be a candidate for an object that has undergone an FU-Ori (FUOR) the outbreak
in the past. This in turn could lead to a time-varying appearance of the dusty
arcs that may be revealed by multi-epoch imaging. In particular, a radial
colour analysis of the dust arcs can then be attempted to check whether radial
grain size distribution was modified by a previous FUOR wind. Second-epoch
imaging of V1331 Cyg was obtained by us in 2009 using the Hubble Space
Telescope (HST). By comparing this to archival HST data from 2000, we studied
the time evolution of the circumstellar nebulae. After a point spread function
subtraction using model point spread functions, we used customised routines to
perform a proper motion analysis. The nebula expansion was first derived by
deconvolving and correlating the two-epoch radial brightness profiles.
Additional data from other facilities TLS, UKIDSS, SPITZER, and HERSCHEL were
also incorporated to improve our understanding of the star in terms of
environment, viewing angle, bipolar outflow length, and the FUOR phenomenon.
The derived radial colour profiles do not indicate a spatial separation of the
dust grain sizes. The HERSCHEL 160 micron images show for the time thermal
emission from dust probably residing in the outer arc. By viewing V1331 Cyg
almost pole-on, the length of the bipolar outflow exceeds previous estimates by
far. The outer arc expansion timescale is consistent with the implantation time
of the CO torus, which supports the hypothesis of an outburst that occurred a
few thousand years ago. The azimuthal colour variation of the outer arc is
probably due to changes of the scattering angle, imposed by a tilt or helical
geometry of the dust configuration.
Chinese: 年轻的恒星V1331 Cyg之前受到关注，因为它周围环绕着一个光学、弧形反射星云。V1331 Cyg通常被认为是一个过去经历过FU-Ori（FUOR）爆发的天体候选者。这反过来可能导致尘埃弧的视星等随时间变化，这些尘埃弧可能通过多时间点成像揭示出来。特别是，可以通过对尘埃弧进行径向颜色分析来检查径向颗粒大小分布是否被之前的FUOR风所改变。我们于2009年使用哈勃太空望远镜（HST）获得了V1331 Cyg的第二时间点成像。通过将其与2000年的存档HST数据进行比较，我们研究了 circumstellar nebulae 的时间演化。在用模型点扩散函数进行点扩散函数减法后，我们使用定制的程序进行了自行的运动分析。通过解卷积和相关性分析两个时间点的径向亮度分布，首先推导出了星云的膨胀。我们还结合了来自其他设施（TLS、UKIDSS、SPITZER和HERSCHEL）的数据，以改善我们对该恒星在环境、视向角度、双极喷流长度和FUOR现象方面的理解。推导出的径向颜色分布没有显示出尘埃颗粒大小的空间分离。HERSCHEL 160微米图像显示，尘埃可能位于外弧，其热辐射可能是时间相关的。通过几乎极向观测V1331 Cyg，双极喷流的长度远远超过了之前的估计。外弧的膨胀时间尺度与CO环的植入时间一致，这支持了几千年前发生爆发假说的观点。外弧的方位角颜色变化可能是由于尘埃配置的倾斜或螺旋几何形状导致的散射角变化。
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English: We classify the possible bosonic and Type 0 unoriented string theories in two
dimensions, and find their dual matrix(-vector) models. There are no RP^2 R-R
tadpoles in any of the models, but many of them possess a massless tachyon
tadpole. Thus all the models we find are consistent two-dimensional string
vacua, but some get quantum corrections to their classical tachyon background.
Where possible, we solve the tadpole cancellation condition, and find all the
tachyon tadpole-free theories.
Chinese: 我们分类了二维中可能的玻色子和0型无向弦理论，并找到了它们的对偶矩阵（向量）模型。在这些模型中，没有RP^2 R-R蝾螈，但其中许多具有无质量tachyon蝾螈。因此，我们找到的所有模型都是一致的两维弦真空，但其中一些对它们的经典tachyon背景进行了量子修正。在可能的情况下，我们解决了蝾螈抵消条件，并找到了所有无tachyon蝾螈的理论。
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English: We study scalar conformal field theories whose large $N$ spectrum is fixed by
the operator dimensions of either Ising model or Lee-Yang edge singularity.
Using numerical bootstrap to study CFTs with $S_N\otimes Z_2$ symmetry, we find
a series of kinks whose locations approach
$(\Delta^{\text{Ising}}_{\sigma},\Delta^{\text{Ising}}_{\epsilon})$ at
$N\rightarrow \infty$. Setting $N=4$, we study the cubic anisotropic fixed
point with three spin components. As byproducts of our numerical bootstrap
work, we discover another series of kinks whose identification with previous
known CFTs remains a mystery. We also show that "minimal models" of
$\mathcal{W}_3$ algebra saturate the numerical bootstrap bounds of CFTs with
$S_3$ symmetry.
Chinese: 我们研究标量共形场论，其大$N$谱由伊辛模型或李-杨边缘奇点的算符维度决定。利用数值引导方法研究具有$S_N\otimes Z_2$对称性的共形场论，我们发现一系列尖点，其位置在$N\rightarrow \infty$时趋近于$(\Delta^{\text{Ising}}_{\sigma},\Delta^{\text{Ising}}_{\epsilon})$。将$N$设为4，我们研究具有三个自旋分量的三次各向异性固定点。作为我们数值引导工作的副产品，我们发现另一系列尖点，其与先前已知共形场论的识别仍然是一个谜。我们还表明，$\mathcal{W}_3$代数的“最小模型”饱和了具有$S_3$对称性的共形场论的数值引导界限。
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English: We study the evolution of the mass function in young and dense star clusters
by means of direct N-body simulations. Our main aim is to explain the recent
observations of the relatively flat mass function observed near the centre of
the Arches star cluster. In this region, the power law index of the mass
function for stars more massive than about 5-6 solar mass, is larger than the
Salpeter value by about unity; whereas further out, and for the lower mass
stars, the mass function resembles the Salpeter distribution. We show that the
peculiarities in the Arches mass function can be explained satisfactorily
without primordial mass segregation. We draw two conclusions from our
simulations: 1) The Arches initial mass function is consistent with a Salpeter
slope down to ~1 solar mass, 2) The cluster is about half way towards core
collapse. The cores of other star clusters with characteristics similar to
those of the Arches are expected to show similar flattening in the mass
functions for the high mass (>5 solar mass) stars.
Chinese: 我们通过直接N体模拟研究年轻和密集星团中质量函数的演化。我们的主要目的是解释最近在弓箭座星团中心附近观察到的相对平坦的质量函数。在这个区域，对于质量大于约5-6个太阳质量的恒星，质量函数的幂律指数比Salpeter值大一个单位；而更外围，对于质量较低的恒星，质量函数则类似于Salpeter分布。我们表明，弓箭座质量函数的异常可以通过不涉及原始质量分离来满意地解释。我们从我们的模拟中得出两个结论：1）弓箭座的初始质量函数与Salpeter斜率一致，直至约1个太阳质量，2）该星团大约处于核心塌陷的一半路程。预计具有与弓箭座类似特征的其它星团的核心将显示出类似的高质量（>5个太阳质量）恒星质量函数的平坦化。
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English: In the missing data literature, the Maximum Likelihood Estimator (MLE) is
celebrated for its ignorability property under missing at random (MAR) data.
However, its sensitivity to misspecification of the (complete) data model, even
under MAR, remains a significant limitation. This issue is further exacerbated
by the fact that the MAR assumption may not always be realistic, introducing an
additional source of potential misspecification through the missingness
mechanism. To address this, we propose a novel M-estimation procedure based on
the Maximum Mean Discrepancy (MMD), which is provably robust to both model
misspecification and deviations from the assumed missingness mechanism. Our
approach offers strong theoretical guarantees and improved reliability in
complex settings. We establish the consistency and asymptotic normality of the
estimator under missingness completely at random (MCAR), provide an efficient
stochastic gradient descent algorithm, and derive error bounds that explicitly
separate the contributions of model misspecification and missingness bias.
Furthermore, we analyze missing not at random (MNAR) scenarios where our
estimator maintains controlled error, including a Huber setting where both the
missingness mechanism and the data model are contaminated. Our contributions
refine the understanding of the limitations of the MLE and provide a robust and
principled alternative for handling missing data.
Chinese: 在缺失数据文献中，最大似然估计器（MLE）因其在大随机缺失（MAR）数据下的不可观测性属性而备受赞誉。然而，即使在MAR下，其对（完整）数据模型误设的敏感性仍然是一个重要的限制。这一问题进一步加剧了MAR假设可能并不总是现实的这一事实，通过缺失机制引入了潜在的误设的额外来源。为了解决这个问题，我们提出了一种基于最大均值差异（MMD）的新颖的M估计程序，该程序在模型误设和偏离假设的缺失机制方面都具有可证明的鲁棒性。我们的方法在复杂环境下提供了强大的理论保证和改进的可靠性。我们证明了在完全随机缺失（MCAR）下估计量的一致性和渐近正态性，提供了一种有效的随机梯度下降算法，并推导出误差界限，明确区分了模型误设和缺失偏差的贡献。此外，我们还分析了我们的估计器在缺失非随机（MNAR）场景下保持受控误差的情况，包括一个Huber设置，其中缺失机制和数据模型都受到了污染。我们的贡献深化了对MLE局限性的理解，并为处理缺失数据提供了一种稳健且原则性的替代方案。
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English: The study of Mutually Unbiased Bases continues to be developed vigorously,
and presents several challenges in the Quantum Information Theory. Two
orthonormal bases in $\mathbb C^d, B {and} B'$ are said mutually unbiased if
$\forall b\in B, b'\in B'$ the scalar product $b\cdot b'$ has modulus
$d^{-1/2}$. In particular this property has been introduced in order to allow
an optimization of the measurement-driven quantum evolution process of any
state $\psi \in \mathbb C^d$ when measured in the mutually unbiased bases
$B\_{j} {of} \mathbb C^d$. At present it is an open problem to find the maximal
umber of mutually Unbiased Bases when $d$ is not a power of a prime number.
\noindent In this article, we revisit the problem of finding Mutually Unbiased
Bases (MUB's) in any dimension $d$. The method is very elementary, using the
simple unitary matrices introduced by Schwinger in 1960, together with their
diagonalizations. The Vandermonde matrix based on the $d$-th roots of unity
plays a major role. This allows us to show the existence of a set of 3 MUB's in
any dimension, to give conditions for existence of more than 3 MUB's for $d$
even or odd number, and to recover the known result of existence of $d+1$ MUB's
for $d$ a prime number. Furthermore the construction of these MUB's is very
explicit. As a by-product, we recover results about Gauss Sums, known in number
theory, but which have apparently not been previously derived from MUB
properties.
Chinese: 相互 unbiased 基础的研究仍在积极发展，并在量子信息理论中提出了若干挑战。在 $\mathbb C^d$ 中，两个正交归一基 $B$ 和 $B'$ 被称为相互 unbiased，如果对于所有 $b \in B$ 和 $b' \in B'$，标量积 $b \cdot b'$ 的模为 $d^{-1/2}$。特别是，这一性质被引入以允许优化在相互 unbiased 基 $B_j$ 中对任何状态 $\psi \in \mathbb C^d$ 的测量驱动的量子演化过程。目前，当 $d$ 不是素数的幂时，寻找最大数量的相互 unbiased 基是一个开放问题。
\noindent 在本文中，我们重新审视在任何维度 $d$ 中寻找相互 unbiased 基（MUB's）的问题。该方法非常基础，使用了 Schwinger 在 1960 年引入的简单酉矩阵及其对角化。基于 $d$ 次单位根的 Vandermonde 矩阵起着关键作用。这使我们能够证明在任何维度中都存在一组 3 个 MUB，给出 $d$ 为偶数或奇数时存在超过 3 个 MUB 的条件，并恢复当 $d$ 为素数时存在 $d+1$ 个 MUB 的已知结果。此外，这些 MUB 的构造非常明确。作为副产品，我们恢复了数论中关于 Gauss 和的结果，但这些结果显然尚未从 MUB 性质中推导出来。
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English: Automatic music transcription (AMT) aims to convert raw audio to symbolic
music representation. As a fundamental problem of music information retrieval
(MIR), AMT is considered a difficult task even for trained human experts due to
overlap of multiple harmonics in the acoustic signal. On the other hand, speech
recognition, as one of the most popular tasks in natural language processing,
aims to translate human spoken language to texts. Based on the similar nature
of AMT and speech recognition (as they both deal with tasks of translating
audio signal to symbolic encoding), this paper investigated whether a generic
neural network architecture could possibly work on both tasks. In this paper,
we introduced our new neural network architecture built on top of the current
state-of-the-art Onsets and Frames, and compared the performances of its
multiple variations on AMT task. We also tested our architecture with the task
of speech recognition. For AMT, our models were able to produce better results
compared to the model trained using the state-of-art architecture; however,
although similar architecture was able to be trained on the speech recognition
task, it did not generate very ideal result compared to other task-specific
models.
Chinese: 自动音乐转录（AMT）旨在将原始音频转换为符号音乐表示。作为音乐信息检索（MIR）的一个基本问题，AMT由于声学信号中多个谐波的叠加，被认为是训练有素的专家都难以完成的任务。另一方面，语音识别作为自然语言处理中最受欢迎的任务之一，旨在将人类口语转换为文本。基于AMT和语音识别的相似性（因为它们都涉及将音频信号转换为符号编码的任务），本文研究了通用的神经网络架构是否可能同时适用于这两个任务。在本文中，我们基于当前的Onsets and Frames技术，引入了我们的新型神经网络架构，并比较了其多种变体在AMT任务上的性能。我们还用语音识别任务测试了我们的架构。对于AMT，我们的模型能够产生比使用最先进架构训练的模型更好的结果；然而，尽管类似的架构能够在语音识别任务上进行训练，但与其他任务特定模型相比，它并没有产生非常理想的结果。
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English: We study the nonequilibrium transport through a multichannel Kondo quantum
dot in the presence of a magnetic field. We use the exact solution of the
two-loop renormalization group equation to derive analytical results for the g
factor, the spin relaxation rates, the magnetization, and the differential
conductance. We show that the finite magnetization leads to a coupling between
the conduction channels which manifests itself in additional features in the
differential conductance.
Chinese: 我们研究了在有磁场存在的情况下，通过多通道Kondo量子点的非平衡输运。我们使用两-loop重整化群方程的精确解来推导g因子、自旋弛豫率、磁化和微分电导的解析结果。我们表明，有限的磁化导致传导通道之间的耦合，这在微分电导中表现为额外的特征。
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English: Space-time adaptive processing (STAP) is an effective tool for detecting a
moving target in spaceborne or airborne radar systems. Statistical-based STAP
methods generally need sufficient statistically independent and identically
distributed (IID) training data to estimate the clutter characteristics.
However, most actual clutter scenarios appear only locally stationary and lack
sufficient IID training data. In this paper, by exploiting the intrinsic
sparsity of the clutter distribution in the angle-Doppler domain, a new STAP
algorithm called SR-STAP is proposed, which uses the technique of sparse
recovery to estimate the clutter space-time spectrum. Joint sparse recovery
with several training samples is also used to improve the estimation
performance. Finally, an effective clutter covariance matrix (CCM) estimate and
the corresponding STAP filter are designed based on the estimated clutter
spectrum. Both the Mountaintop data and simulated experiments have illustrated
the fast convergence rate of this approach. Moreover, SR-STAP is less dependent
on prior knowledge, so it is more robust to the mismatch in the prior knowledge
than knowledge-based STAP methods. Due to these advantages, SR-STAP has great
potential for application in actual clutter scenarios.
Chinese: 空间时间自适应处理（STAP）是太空或空中雷达系统中检测移动目标的有效工具。基于统计的STAP方法通常需要足够的统计上独立且同分布（IID）的训练数据来估计杂波特性。然而，大多数实际的杂波场景只表现出局部平稳性，缺乏足够的IID训练数据。在本文中，通过利用角度-多普勒域中杂波分布的内在稀疏性，提出了一种新的STAP算法称为SR-STAP，该算法使用稀疏恢复技术来估计杂波的空间时间谱。同时，使用多个训练样本的联合稀疏恢复来提高估计性能。最后，基于估计的杂波谱设计了有效的杂波协方差矩阵（CCM）估计和相应的STAP滤波器。山峰数据和模拟实验都证明了这种方法的快速收敛率。此外，SR-STAP对先验知识的依赖性较小，因此在先验知识的不匹配情况下比基于知识的STAP方法更具有鲁棒性。由于这些优点，SR-STAP在实际的杂波场景中有很大的应用潜力。
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English: Cayley-Dickson doubling procedure is used to construct the root systems of
some celebrated Lie algebras in terms of the integer elements of the division
algebras of real numbers, complex numbers, quaternions and octonions. Starting
with the roots and weights of SU(2) expressed as the real numbers one can
construct the root systems of the Lie algebras of SO(4),SP(2)=
SO(5),SO(8),SO(9),F_{4} and E_{8} in terms of the discrete elements of the
division algebras. The roots themselves display the group structures besides
the octonionic roots of E_{8} which form a closed octonion algebra. The
automorphism group Aut(F_{4}) of the Dynkin diagram of F_{4} of order 2304, the
largest crystallographic group in 4-dimensional Euclidean space, is realized as
the direct product of two binary octahedral group of quaternions preserving the
quaternionic root system of F_{4}.The Weyl groups of many Lie algebras, such
as, G_{2},SO(7),SO(8),SO(9),SU(3)XSU(3) and SP(3)X SU(2) have been constructed
as the subgroups of Aut(F_{4}). We have also classified the other non-parabolic
subgroups of Aut(F_{4}) which are not Weyl groups. Two subgroups of orders192
with different conjugacy classes occur as maximal subgroups in the finite
subgroups of the Lie group $G_{2}$ of orders 12096 and 1344 and proves to be
useful in their constructions. The triality of SO(8) manifesting itself as the
cyclic symmetry of the quaternionic imaginary units e_{1},e_{2},e_{3} is used
to show that SO(7) and SO(9) can be embedded triply symmetric way in SO(8) and
F_{4} respectively.
Chinese: Cayley-Dickson翻倍过程被用来通过实数、复数、四元数和八元数除法代数中的整数元素来构造一些著名李代数的根系。从SU(2)的根和权重开始，用实数表示，可以构造SO(4)、SP(2)=SO(5)、SO(8)、SO(9)、F_4和E_8的李代数的根系，用除法代数中的离散元素表示。根本身除了E_8的八元数根，它们形成了一个封闭的八元数代数之外，还展示了群结构。F_4的Dynkin图的Aut(F_4)自同构群，阶数为2304，是4维欧几里得空间中最大的晶体群，被实现为两个保持F_4的复数根系的四元数二面体群直积。许多李代数的Weyl群，如G_2、SO(7)、SO(8)、SO(9)、SU(3)XSU(3)和SP(3)X SU(2)，被构造为Aut(F_4)的子群。我们还对Aut(F_4)中不是Weyl群的非准抛物子群进行了分类。两个具有不同共轭类的子群，阶数为192，作为最大子群出现在李群$G_{2}$的有限子群中，阶数为12096和1344，在它们的构造中证明是有用的。SO(8)的三位一体，体现在四元数虚单位e_1、e_2、e_3的循环对称性中，被用来表明SO(7)和SO(9)可以以三位一体对称的方式嵌入SO(8)和F_4中。
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English: We present preliminary results for heavy to light transitions of pseudoscalar
mesons, induced by the vector and tensor operators. This lattice study is
performed in quenched approximation, by using the nonperturbatively improved
Wilson action and operators. We also update the values of the heavy-light meson
decay constants.
Chinese: 我们展示了伪标量介子从重到轻的过渡的初步结果，这些过渡是由矢量算符和张量算符诱导的。这项晶格研究是在淬火近似下进行的，使用了非微扰改进的威尔逊作用和算符。我们还更新了重轻介子衰变常数的值。
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English: The optical flow guidance strategy is ideal for obtaining motion information
of objects in the video. It is widely utilized in video segmentation tasks.
However, existing optical flow-based methods have a significant dependency on
optical flow, which results in poor performance when the optical flow
estimation fails for a particular scene. The temporal consistency provided by
the optical flow could be effectively supplemented by modeling in a structural
form. This paper proposes a new hierarchical graph neural network (GNN)
architecture, dubbed hierarchical graph pattern understanding (HGPU), for
zero-shot video object segmentation (ZS-VOS). Inspired by the strong ability of
GNNs in capturing structural relations, HGPU innovatively leverages motion cues
(\ie, optical flow) to enhance the high-order representations from the
neighbors of target frames. Specifically, a hierarchical graph pattern encoder
with message aggregation is introduced to acquire different levels of motion
and appearance features in a sequential manner. Furthermore, a decoder is
designed for hierarchically parsing and understanding the transformed
multi-modal contexts to achieve more accurate and robust results. HGPU achieves
state-of-the-art performance on four publicly available benchmarks (DAVIS-16,
YouTube-Objects, Long-Videos and DAVIS-17). Code and pre-trained model can be
found at \url{https://github.com/NUST-Machine-Intelligence-Laboratory/HGPU}.
Chinese: 光流引导策略非常适合获取视频中对象的运动信息。它在视频分割任务中得到广泛应用。然而，现有的基于光流的方法对光流有显著的依赖性，当特定场景的光流估计失败时，会导致性能下降。光流提供的时间一致性可以通过结构建模得到有效补充。本文提出了一种新的分层图神经网络（GNN）架构，称为分层图模式理解（HGPU），用于零样本视频对象分割（ZS-VOS）。受到GNN在捕捉结构关系方面强大能力的影响，HGPU创新性地利用运动线索（即，光流）来增强目标帧邻居的高阶表示。具体来说，引入了一种具有消息聚合的分层图模式编码器，以顺序方式获取不同级别的运动和外观特征。此外，还设计了一个解码器，用于分层解析和理解转换后的多模态上下文，以实现更准确和鲁棒的结果。HGPU在四个公开可用的基准测试（DAVIS-16、YouTube-Objects、Long-Videos和DAVIS-17）上达到了最先进的性能。代码和预训练模型可以在\url{https://github.com/NUST-Machine-Intelligence-Laboratory/HGPU}找到。
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English: Ultracold atoms in optical lattice provides a platform to realize the
superfluid (SF) state, a quantum order with paired charge-neutral fermions. In
this paper, we studied SF state in the twodimensional attractive Hubbard model
with pi-flux on each plaquette. The SF state in the pi-flux lattice model
suffers very strong quantum fluctuations and the ground state becomes a
possible quantum phase liquid state. In this phase, there exists the Cooper
pairing together with a finite energy gap for the atoms, but no long range SF
phase coherence exists at zero temperature. In addition, we discussed the
properties of the SF vortices.
Chinese: 超冷原子光学晶格为实现超流(SF)态——一种配对的中性费米子的量子有序态——提供了平台。在本文中，我们研究了具有每个单位胞π通量的二维吸引哈伯德模型中的超流态。在π通量晶格模型中，超流态存在非常强的量子涨落，基态可能成为量子相液态。在此相中，存在库珀配对，且原子具有有限能量间隙，但在零温下不存在长程超流相干性。此外，我们还讨论了超流涡旋的性质。
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English: We report on the relation between the mass of supermassive black holes
(SMBHs; M_BH) and that of hosting dark matter halos (M_h) for 49 z ~ 6
quasi-stellar objects (QSOs) with [CII]158um velocity-width measurements. Here,
we estimate M_h assuming that the rotation velocity from FWHM_CII is equal to
the circular velocity of the halo; we have tested this procedure using z ~ 3
QSOs that also have clustering-based M_h estimates. We find that a vast
majority of the z ~ 6 SMBHs are more massive than expected from the local M_BH
- M_h relation, with one-third of the sample by factors >~ 10^2. The median
mass ratio of the sample, M_BH/M_h = 6 x 10^{-4}, means that 0.4% of the
baryons in halos are locked up in SMBHs. The mass growth rates of our SMBHs
amount to ~ 10% of the SFRs, or ~ 1% of the mean baryon accretion rates, of the
hosting galaxies. A large fraction of the hosting galaxies are consistent with
average galaxies in terms of SFR and perhaps of stellar mass and size. Our
study indicates that the growth of SMBHs (M_BH ~ 10^{8-10} Msun) in luminous z
~ 6 QSOs greatly precedes that of hosting halos owing to efficient gas
accretion even under normal star formation activities, although we cannot rule
out the possibility that undetected SMBHs have local M_BH/M_h ratios. This
preceding growth is in contrast to much milder evolution of the stellar-to-halo
mass ratio.
Chinese: 我们报道了关于49个红移z~6类星体（QSOs）中超大质量黑洞（SMBHs；M_BH）与宿主暗物质晕（M_h）质量之间的关系，这些类星体具有[CII]158um速度宽度的测量值。在此，我们假设FWHM_CII的旋转速度等于晕的圆周速度，从而估计了M_h；我们使用红移z~3的类星体（这些类星体也有基于团簇的M_h估计值）来检验了这一程序。我们发现，绝大多数z~6的SMBHs的质量比局部M_BH - M_h关系预期的要大，其中样本的三分之一的比例超过了10^2倍。样本的中值质量比M_BH/M_h = 6 x 10^{-4}，这意味着晕中0.4%的核子被锁在SMBHs中。我们SMBHs的质量增长率相当于宿主星系星形成率（SFRs）的约10%，或平均核子吸积率的约1%。大部分宿主星系在SFR方面与平均星系一致，可能在恒星质量和尺寸方面也是如此。我们的研究表明，在明亮z~6类星体中，SMBHs（M_BH ~ 10^{8-10} Msun）的增长（由于即使在正常星形成活动下高效的气体吸积）大大早于宿主晕的增长，尽管我们不能排除未探测到的SMBHs具有局部M_BH/M_h比率的可能性。这种先前的增长与恒星-晕质量比演变得缓和形成鲜明对比。
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English: We report on D0 searches for leptoquarks (LQ) predicted in extended gauge
theories and composite models to explain the symmetry between quarks and
leptons. Data samples obtained with the D0 detector from proton-antiproton
collisions at a center-of-mass energy of 1.96 TeV corresponding to intergrated
luminosities of 1--4 inverse-fb were analyzed. No evidence for the production
of such particles were observed and lower limits on leptoquark masses are set.
Chinese: 我们报告了D0探测器在质子-反质子碰撞中，在1.96 TeV的质心能量下，对应于1--4 fb的积分亮度所获得的数据样本，对预测在扩展规范理论和复合模型中解释夸克和轻子对称性的轻子夸克（LQ）的搜索结果。未观察到此类粒子的产生证据，并设定了轻子夸克质量的下限。
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English: The Informational Braess' Paradox (IBP) illustrates a counterintuitive
scenario where revelation of additional roadway segments to some
self-interested travelers leads to increased travel times for these
individuals. IBP extends the original Braess' paradox by relaxing the
assumption that all travelers have identical and complete information about the
network. In this paper, we study the conditions under which IBP does not occur
in networks with non-atomic selfish travelers and multiple origin-destination
pairs. Our results completely characterize the network topologies immune to
IBP, thus resolving an open question proposed by Acemoglu et al.
Chinese: 信息 Braess 矛盾（IBP）描绘了一个反直觉的场景，即向某些自私的旅行者揭示额外的公路段会导致这些个人的旅行时间增加。IBP通过放松所有旅行者都具有相同且完整网络信息的假设，扩展了原始的 Braess 矛盾。在这篇论文中，我们研究了在具有非原子自私旅行者和多个出发地-目的地对的网络中，IBP不发生的条件。我们的结果完全描述了不受IBP影响的网络拓扑结构，从而解决了 Acemoglu 等人提出的一个开放问题。
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English: We explore the downstream task performances for graph neural network (GNN)
self-supervised learning (SSL) methods trained on subgraphs extracted from
relational databases (RDBs). Intuitively, this joint use of SSL and GNNs should
allow to leverage more of the available data, which could translate to better
results. However, we found that naively porting contrastive SSL techniques can
cause ``negative transfer'': linear evaluation on fixed representations from a
pretrained model performs worse than on representations from the
randomly-initialized model. Based on the conjecture that contrastive SSL
conflicts with the message passing layers of the GNN, we propose InfoNode: a
contrastive loss aiming to maximize the mutual information between a node's
initial- and final-layer representation. The primary empirical results support
our conjecture and the effectiveness of InfoNode.
Chinese: 我们探讨了在从关系型数据库（RDBs）中提取的子图上训练的图神经网络（GNN）自监督学习（SSL）方法的下游任务性能。直观地讲，这种SSL和GNN的联合使用应该能够充分利用可用数据，这可能会带来更好的结果。然而，我们发现，简单地移植对比SSL技术会导致“负迁移”：在预训练模型的预定义表示上进行线性评估，其性能比在随机初始化模型的表示上进行评估要差。基于对比SSL与GNN的消息传递层可能存在冲突的假设，我们提出了InfoNode：一个旨在最大化节点的初始层和最终层表示之间互信息的对比损失。主要的实验结果支持了我们的假设和InfoNode的有效性。
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English: Retrieval augmentation has become an effective solution to empower large
language models (LLMs) with external and verified knowledge sources from the
database, which overcomes the limitations and hallucinations of LLMs in
handling up-to-date and domain-specific information. However, existing
embedding models for text retrieval usually have three non-negligible
limitations. First, the number and diversity of samples in a batch are too
restricted to supervise the modeling of textual nuances at scale. Second, the
high proportional noise are detrimental to the semantic correctness and
consistency of embeddings. Third, the equal treatment to easy and difficult
samples would cause sub-optimum convergence of embeddings with poorer
generalization. In this paper, we propose the PEG, a progressively learned
embeddings for robust text retrieval. Specifically, we increase the training
in-batch negative samples to 80,000, and for each query, we extracted five hard
negatives. Concurrently, we incorporated a progressive learning mechanism,
enabling the model to dynamically modulate its attention to the samples
throughout the entire training process. Additionally, PEG is trained on more
than 100 million data, encompassing a wide range of domains (e.g., finance,
medicine, and tourism) and covering various tasks (e.g., question-answering,
machine reading comprehension, and similarity matching). Extensive experiments
conducted on C-MTEB and DuReader demonstrate that PEG surpasses
state-of-the-art embeddings in retrieving true positives, highlighting its
significant potential for applications in LLMs. Our model is publicly available
at https://huggingface.co/TownsWu/PEG.
Chinese: 检索增强已成为一种有效解决方案，能够为大型语言模型（LLMs）提供来自数据库的外部和经过验证的知识来源，从而克服LLMs在处理最新信息和特定领域信息时存在的局限性和幻觉。然而，现有的文本检索嵌入模型通常存在三个不可忽视的局限性。首先，批次中样本的数量和多样性过于受限，无法大规模地监督文本细微之处的建模。其次，高比例的噪声会损害嵌入的语义正确性和一致性。第三，对简单和困难样本的同等处理会导致泛化能力较差的嵌入出现次优收敛。在本文中，我们提出了PEG，一种用于鲁棒文本检索的逐步学习嵌入。具体而言，我们将训练批次内的负样本数量增加到80,000，并且对于每个查询，我们提取五个难负样本。同时，我们引入了逐步学习机制，使模型能够在整个训练过程中动态调节其对样本的注意力。此外，PEG在超过1亿条数据上进行训练，涵盖了广泛领域（例如金融、医学和旅游）以及各种任务（例如问答、机器阅读理解和相似度匹配）。在C-MTEB和DuReader上的大量实验表明，PEG在检索真正例方面优于现有最佳嵌入，突显了其在LLMs应用中的巨大潜力。我们的模型可在https://huggingface.co/TownsWu/PEG公开获取。
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English: The Rabi model, a two-level atom coupled to a harmonic oscillator, can
undergo a second-order quantum phase transition (QPT) [M. -J. Hwang et al,
Phys. Rev. Lett. 115, 180404 (2015)]. Here we show that the Rabi QPT
accompanies critical behavior in the higher energy excited states, i.e., the
excited-state QPT (ESQPT). We derive analytic expressions for the semiclassical
density of states, which shows a logarithmic divergence at a critical energy
eigenvalue in the broken symmetry (superradiant) phase. Moreover, we find that
the logarithmic singularities in the density of states leads to singularities
in the relevant observables in the system such as photon number and atomic
polarization. We corroborate our analytical semiclassical prediction of the
ESQPT in the Rabi model with its numerically exact quantum mechanical solution.
Chinese: Rabi模型，一个与谐振子耦合的双能级原子，可以经历二级量子相变（QPT）[M. -J. Hwang等人，物理评论快报115，180404（2015）]。在这里，我们表明Rabi QPT伴随着高能激发态中的临界行为，即激发态量子相变（ESQPT）。我们推导出了半经典态密度的解析表达式，该表达式在破缺对称性（超辐射）相中的临界能量本征值处显示出对数发散。此外，我们发现态密度中的对数奇异性导致了系统中相关可观测量（如光子数和原子极化）的奇异性。我们通过Rabi模型的数值精确量子力学解来证实了我们关于ESQPT的解析半经典预测。
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English: Animals form groups for many reasons but there are costs and benefit
associated with group formation. One of the benefits is collective memory. In
groups on the move, social interactions play a crucial role in the cohesion and
the ability to make consensus decisions. When migrating from spawning to
feeding areas fish schools need to retain a collective memory of the
destination site over thousand of kilometers and changes in group formation or
individual preference can produce sudden changes in migration pathways. We
propose a modelling framework, based on stochastic adaptive networks, that can
reproduce this collective behaviour. We assume that three factors control group
formation and school migration behaviour: the intensity of social interaction,
the relative number of informed individuals and the preference that each
individual has for the particular migration area. We treat these factors
independently and relate the individuals' preferences to the experience and
memory for certain migration sites. We demonstrate that removal of knowledgable
individuals or alteration of individual preference can produce rapid changes in
group formation and collective behavior. For example, intensive fishing
targeting the migratory species and also their preferred prey can reduce both
terms to a point at which migration to the destination sites is suddenly
stopped. The conceptual approaches represented by our modelling framework may
therefore be able to explain large-scale changes in fish migration and spatial
distribution.
Chinese: 动物形成群体有多种原因，但群体形成与成本和收益相关。其中一项收益是集体记忆。在移动的群体中，社会互动在群体凝聚力和共识决策能力中起着关键作用。当鱼类从产卵区迁徙到觅食区时，鱼群需要保持对目的地数千里之遥的集体记忆，群体组成或个体偏好的变化可能导致迁徙路线的突然改变。我们提出一个基于随机适应网络的建模框架，能够重现这种集体行为。我们假设有三个因素控制群体形成和鱼群迁徙行为：社会互动强度、知情个体的相对数量以及每个个体对特定迁徙区域的偏好。我们独立处理这些因素，并将个体的偏好与对特定迁徙区域的经验和记忆联系起来。我们证明，移除知情个体或改变个体偏好会导致群体形成和集体行为的快速变化。例如，针对迁徙物种及其偏好猎物的强化捕捞，可将这两个因素降低到目的地迁徙突然停止的程度。因此，我们建模框架所代表的概念方法可能能够解释鱼类迁徙和空间分布的大规模变化。
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English: The quantum dynamical evolution of atomic and molecular aggregates, from
their compact to their fragmented states, is parametrized by a single
collective radial parameter. Treating all the remaining particle coordinates in
d dimensions democratically, as a set of angles orthogonal to this collective
radius or by equivalent variables, bypasses all independent-particle
approximations. The invariance of the total kinetic energy under arbitrary
d-dimensional transformations which preserve the radial parameter gives rise to
novel quantum numbers and ladder operators interconnecting its eigenstates at
each value of the radial parameter.
We develop the systematics and technology of this approach, introducing the
relevant mathematics tutorially, by analogy to the familiar theory of angular
momentum in three dimensions. The angular basis functions so obtained are
treated in a manifestly coordinate-free manner, thus serving as a flexible
generalized basis for carrying out detailed studies of wavefunction evolution
in multi-particle systems.
Chinese: 原子和分子聚集体从其凝聚态到碎片态的量子动力学演化由单一集体径向参数表征。将所有剩余的粒子坐标在d维中平等地处理，作为一组与该集体半径正交的角度或等效变量，绕过所有独立粒子近似。总动能对保持径向参数的任意d维变换的不变性，产生新的量子数和阶梯算符，连接其在每个径向参数值的本征态。
我们发展该方法的系统性和技术，通过类比熟悉的3维角动量理论，以教程形式引入相关数学。所得角基函数以明显无坐标的方式处理，作为灵活的广义基，用于在多粒子系统中进行波函数演化的详细研究。
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English: We present a rigorous analysis of the phenomenon of decoherence for general
$N-$level systems coupled to reservoirs. The latter are described by free
massless bosonic fields. We apply our general results to the specific cases of
the qubit and the quantum register. We compare our results with the explicitly
solvable case of systems whose interaction with the environment does not allow
for energy exchange (non-demolition, or energy conserving interactions). We
suggest a new approach which applies to a wide variety of systems which are not
explicitly solvable.
Chinese: 我们针对与储水池耦合的通用$N$级系统中的退相干现象进行了严格分析。后者由无质量自由玻色子场描述。我们将我们的通用结果应用于比特和量子寄存器的特定情况。我们将我们的结果与那些与环境相互作用不允许能量交换（非破坏性，或能量守恒相互作用）的系统的可解情况进行了比较。我们提出了一种适用于广泛系统的新的方法，这些系统不能被显式求解。
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English: Large language models (LLMs) are increasingly integrated with specialized
external tools, yet many tasks demand zero-shot tool usage with minimal or
noisy documentation. Existing solutions rely on manual rewriting or labeled
data for validation, making them inapplicable in true zero-shot settings. To
address these challenges, we propose PLAY2PROMPT, an automated framework that
systematically "plays" with each tool to explore its input-output behaviors.
Through this iterative trial-and-error process, PLAY2PROMPT refines tool
documentation and generates usage examples without any labeled data. These
examples not only guide LLM inference but also serve as validation to further
enhance tool utilization. Extensive experiments on real-world tasks demonstrate
that PLAY2PROMPT significantly improves zero-shot tool performance across both
open and closed models, offering a scalable and effective solution for
domain-specific tool integration.
Chinese: 大型语言模型（LLMs）正越来越多地与专业外部工具集成，然而许多任务需要零样本工具使用且文档极少或存在噪声。现有解决方案依赖人工重写或标记数据进行验证，导致它们在真正的零样本场景中不适用。为应对这些挑战，我们提出了PLAY2PROMPT，这是一个自动化的框架，通过系统性地"玩"（试验）每个工具来探索其输入输出行为。通过这种迭代试错过程，PLAY2PROMPT无需任何标记数据即可优化工具文档并生成使用示例。这些示例不仅指导LLM推理，还作为验证手段进一步提升工具利用率。在真实世界任务上的大量实验表明，PLAY2PROMPT显著提升了开放模型和封闭模型在零样本工具场景下的性能，为特定领域工具集成提供了一种可扩展且有效的解决方案。
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English: Nanoparticles tethered with DNA strands are promising building blocks for
bottom-up nanotechnology, and a theoretical understanding is important for
future development. Here we build on approaches developed in polymer physics to
provide theoretical descriptions for the equilibrium clustering and dynamics,
as well as the self-assembly kinetics of DNA-linked nanoparticles. Striking
agreement is observed between the theory and molecular modeling of DNA tethered
nanoparticles.
Chinese: 与DNA链连接的纳米颗粒是自下而上纳米技术的有希望的构建块，对其理论理解对未来发展至关重要。在这里，我们基于聚合物物理学中开发的方法，为DNA连接纳米颗粒的平衡聚集和动力学，以及自组装动力学提供了理论描述。观察到理论与DNA连接纳米颗粒的分子建模之间具有显著的一致性。
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English: The effects of entanglement and spin-spin collision on the gauge field in
ultracold atoms are presented in this paper. Two gauge fields are calculated
and discussed. One of the fields comes from space dependent spin-spin
collisions in ultra-cold atoms, while another results from the usual
Born-Oppenheimer method, which separates the center-of-mass motion from the
relative motion in the two-body problem. Adiabatic conditions that lead to the
key results of this paper are also presented and discussed. Entanglement shared
between the two atoms is shown to affect the atomic motion. In the presence of
entanglement, the additional scalar potential disappears, this is different
from the case of atoms in separable states.
Chinese: 本文介绍了纠缠和自旋-自旋碰撞对超冷原子中规范场的影响。计算并讨论了两种规范场。其中一种场来自超冷原子中空间依赖的自旋-自旋碰撞，而另一种则源于通常的玻恩-奥本海默方法，该方法将两体问题中的质心运动与相对运动分开。还介绍了导致本文关键结果的绝热条件，并进行了讨论。研究表明，两个原子之间的纠缠会影响原子运动。在纠缠存在的情况下，额外的标量势消失，这与可分离状态的原子情况不同。
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English: Both the combinatorial and the circuit diameters of polyhedra are of interest
to the theory of linear programming for their intimate connection to a
best-case performance of linear programming algorithms.
We study the diameters of dual network flow polyhedra associated to $b$-flows
on directed graphs $G=(V,E)$ and prove quadratic upper bounds for both of them:
the minimum of $(|V|-1)\cdot |E|$ and $\frac{1}{6}|V|^3$ for the combinatorial
diameter, and $\frac{|V|\cdot (|V|-1)}{2}$ for the circuit diameter. The latter
strengthens the cubic bound implied by a result in [De Loera, Hemmecke, Lee;
2014].
Previously, bounds on these diameters have only been known for bipartite
graphs. The situation is much more involved for general graphs. In particular,
we construct a family of dual network flow polyhedra with members that violate
the circuit diameter bound for bipartite graphs by an arbitrary additive
constant. Further, it provides examples of circuit diameter $\frac{4}{3}|V| -
4$.
Chinese: 多面体的组合直径和电路直径对于线性规划理论来说都很有趣，因为它们与线性规划算法的最佳性能密切相关。我们研究了与有向图 $G=(V,E)$ 上的 $b$-流相关的对偶网络流多面体的直径，并为它们两者证明了二次上界：
组合直径的最小值为 $(|V|-1)\cdot |E|$ 和 $\frac{1}{6}|V|^3$，电路直径的最小值为 $\frac{|V|\cdot (|V|-1)}{2}$。后者加强了[De Loera, Hemmecke, Lee; 2014]中隐含的三次上界。
以前，这些直径的上界只对二分图是已知的。对于一般图的情况要复杂得多。特别是，我们构造了一族对偶网络流多面体，其成员违反了二分图的电路直径上界，超过了一个任意的加性常数。此外，它还提供了电路直径为 $\frac{4}{3}|V| - 4$ 的例子。
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English: A numerical analysis of the origin of the atomic-scale contrast in Kelvin
probe force microscopy (KPFM) is presented. Atomistic simulations of the
tip-sample interaction force field have been combined with a non-contact Atomic
Force Microscope/KPFM simulator. The implementation mimics recent experimental
results on the (001) surface of a bulk alkali halide crystal for which
simultaneous atomic-scale topographical and Contact Potential Difference (CPD)
contrasts were reported. The local CPD does reflect the periodicity of the
ionic crystal, but not the magnitude of its Madelung surface potential. The
imaging mechanism relies on the induced polarization of the ions at the
tip-surface interface owing to the modulation of the applied bias voltage. Our
findings are in excellent agreement with previous theoretical expectations and
experimental observations.
Chinese: 对凯尔文探针力显微镜（KPFM）中原子尺度对比度的起源进行数值分析。已经将尖端-样品相互作用力场的原子模拟与非接触式原子力显微镜/KPFM模拟器相结合。该实现模拟了最近在大量碱金属卤化物晶体（001）表面上的实验结果，其中报告了同时的原子尺度地形和接触势差（CPD）对比度。局部CPD确实反映了离子晶体的周期性，但并未反映其Madelung表面势的幅度。成像机制依赖于由于施加偏置电压的调制而在尖端-表面界面处诱导的离子极化。我们的发现与先前的理论预期和实验观察结果完全一致。
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English: The eigenvectors of the Hamiltonian ${\cal H}_{N}$ of $N$-sites quantum spin
chains with elliptic exchange are connected with the double Bloch meromorphic
solutions of the quantum continuous elliptic Calogero-Moser problem. This fact
allows one to find the eigenvectors via the solutions to the system of highly
transcendental equations of Bethe-ansatz type which is presented in explicit
form.
Chinese: 哈密顿量 ${\cal H}_{N}$ 的特征向量与 $N$ 站点量子自旋链的椭圆交换的双波洛赫双曲解析解相关联。这一事实使得人们可以通过求解贝特-安萨茨类型的高超越方程组的解来找到特征向量，这些方程组以显式形式给出。
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English: A filter for universal real-time prediction of band-limited signals is
presented. The filter consists of multiple time-delayed feedback terms in order
to accomplish anticipatory coupling, which again leads to a negative group
delay for frequencies in the baseband. The universality of the filter arises
from its property that it does not rely on a specific model of the signal.
Specifically, as long as the signal to be predicted is band-limited with a
known cutoff frequency, the filter order, the only parameter of the filter,
follows and the filter predicts the signal in real time up to a prediction
horizon that depends on the cutoff frequency, too. It is worked out in detail
how signal prediction arises from the negative group delay of the filter. Its
properties, including stability, are investigated theoretically, by numerical
simulations, and by application to a physiological signal. Possible control and
signal processing applications of this filter are discussed.
Chinese: 提出了一种用于宽带限信号通用实时预测的滤波器。该滤波器由多个时间延迟反馈项组成，以实现预期耦合，这又导致基带频率的负群延迟。滤波器的通用性源于其不依赖于信号特定模型的性质。具体来说，只要待预测的信号具有已知的截止频率且为带限信号，滤波器阶数，即滤波器的唯一参数，就会随之确定，并且滤波器将实时预测信号，预测范围取决于截止频率。详细阐述了信号预测如何从滤波器的负群延迟中产生。通过理论分析、数值模拟以及将其应用于生理信号，研究了该滤波器的性质，包括稳定性。讨论了该滤波器在控制和信号处理领域的潜在应用。
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English: A combinatorial interpretation is given of Devlin's word problem underlying
the classical center-focus problem of Poincare for non-autonomous differential
equations. It turns out that the canonical polynomials of Devlin are from the
point of view of connected graded Hopf algebras intimately related to the
graded components of a Hopf algebra antipode applied to the formal power series
of Ferfera. The link is made by passing through control theory since the Abel
equation, which describes a center, is equivalent to an output feedback
equation, and the Hopf algebra of output feedback is derived from the
composition of iterated integrals rather than just the products of iterated
integrals, which yields the shuffle algebra. This means that the primary
algebraic structure at play in Devlin's approach is actually not the shuffle
algebra, but a Faa di Bruno type Hopf algebra, which is defined in terms of the
shuffle product but is a distinct algebraic structure.
Chinese: 对Poincare非自治微分方程的经典中心-焦点问题背后的Devlin词问题给出了一种组合解释。结果发现，Devlin的典型多项式从连通的升阶Hopf代数的角度来看，与将Ferfera的形式幂级数应用于Hopf代数反对称元的升阶分量密切相关。通过控制理论建立了联系，因为描述中心的Abel方程等价于一个输出反馈方程，而输出反馈Hopf代数是从迭代积分的复合而非迭代积分的乘积中导出的，这产生了置换代数。这意味着在Devlin的方法中起主要作用的初级代数结构实际上不是置换代数，而是一种Faa di Bruno类型的Hopf代数，它通过置换积来定义，但是一种不同的代数结构。
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English: We provide a closed form expression for linear Hodge integrals on the
hyperelliptic locus. Specifically, we find a succinct combinatorial formula for
all intersection numbers on the hyperelliptic locus with one $\lambda$-class,
and powers of a $\psi$-class pulled back along the branch map. This is achieved
by using Atiyah-Bott localization on a stack of stable maps into the orbifold
$[\mathbb{P}^1/\mathbb{Z}_2]$.
Chinese: 我们在超椭圆簇上提供了一个线性霍奇积分的闭式表达式。具体来说，我们找到了一个简洁的组合公式，用于计算超椭圆簇上带有一个λ类的所有交点数，以及沿着分支映射拉回的ψ类的幂。这是通过在稳定映射到 orbifold $[\mathbb{P}^1/\mathbb{Z}_2]$ 的堆上使用阿蒂亚-波特局部化来实现的。
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English: In this work, we numerically demonstrate an infrared frequency-tunable
selective thermal emitter made of graphene covered SiC deep gratings. Full-wave
simulation shows temporally-coherent emission peak associated with magnetic
polariton, whose resonance frequency can be dynamically tuned within the phonon
absorption band of SiC by varying graphene chemical potential. An analytical
inductor-capacitor circuit model is introduced to quantitatively predict the
resonance frequency and further elucidate the mechanism for the tunable
emission peak. Moreover, by depositing multiple layers of graphene sheets onto
the SiC deep gratings, a large tunability of 8.5% in peak frequency can be
obtained to yield the coherent emission covering a broad frequency range from
820 1/cm to 890 1/cm. The novel tunable met-amaterial could pave the way to a
new class of tunable thermal sources in the infrared region.
Chinese: 在这项工作中，我们通过数值方法演示了一种由覆盖石墨烯的SiC深沟槽制成的红外频率可调选择性热发射器。全波仿真显示，与磁等离子体相关的时域相干发射峰，其共振频率可通过改变石墨烯化学势在SiC的声子吸收带内动态调谐。引入解析电感电容电路模型来定量预测共振频率，并进一步阐明可调发射峰的机制。此外，通过在SiC深沟槽上沉积多层石墨烯片，可获得8.5%的峰值频率调谐范围，从而产生覆盖820 1/cm至890 1/cm宽频率范围的相干发射。这种新型可调超材料有望为红外区域的新型可调热源开辟道路。
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English: Shock heating by radio jets is potentially an important process in a range of
environments, as it will increase the entropy of the heated gas. Although this
process is expected to occur in the most powerful radio-loud AGN, strong shocks
have so far only been detected in nearby low-power radio galaxies. Here we
discuss X-ray detections of strong shocks in nearby galaxies, including a new
detection of shocked gas around both lobes of the nearby radio galaxy NGC 3801
with inferred Mach numbers of 3 - 6 and a total injected energy comparable to
the thermal energy of the ISM within 11 kpc. We discuss possible links between
shock heating, AGN fuelling and galaxy mergers and the role of this type of
system in feedback models.
Chinese: 通过射电喷流引起的冲击加热在多种环境中可能是一个重要的过程，因为它会增加加热气体的熵。尽管预计这一过程会在最强大的射电强AGN中发生，但迄今为止，强烈的冲击仅在附近的低功率射电星系中被检测到。在这里，我们讨论了附近星系中强烈冲击的X射线检测，包括对附近射电星系NGC 3801两侧的冲击气体的新发现，其马赫数推断为3-6，总注入能量与11 kpc内ISM的热能相当。我们讨论了冲击加热、AGN供能和星系合并之间的可能联系以及这类系统在反馈模型中的作用。
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English: For the minimal O(N) sigma model, which is defined to be generated by the
O(N) scalar auxiliary field alone, all n-point functions, till order 1/N
included, can be expressed by elementary functions without logarithms.
Consequently, the conformal composite fields of m auxiliary fields possess at
the same order such dimensions, which are m times the dimension of the
auxiliary field plus the order of differentiation.
Chinese: 对于最小化的O(N) sigma模型，该模型仅由O(N)标量辅助场生成，直到包含1/N阶的n点函数，都可以用不含对数的初等函数来表达。因此，m个辅助场的共形复合场在相同阶数上具有这样的维度，即m倍辅助场的维度加上微分阶数。
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English: We present an algorithm for the continuous monitoring of the biomass and
ethanol concentrations and moreover the kinetic rate in the Mezcal fermentation
process. This algorithm performs its task having only available the on-line
measurements of the redox potential. The procedure includes an artificial
neural network (ANN) that relates the redox potential to the ethanol and
biomass concentrations. Then a nonlinear-observer-based algorithm uses the
biomass estimations to infer the kinetic rate of this fermentation process. The
method shows that the redox potential is a valuable indicator of microorganism
metabolic activity during the Mezcal fermentation. In addition, the estimated
kinetic rate can be considered as a direct evidence of the presence of mixed
culture growth in the process. In this work, the detailed design of the
software-sensor is presented, as well as its experimental application at the
laboratory level
Chinese: 我们提出了一种用于连续监测生物质和乙醇浓度以及梅斯卡尔发酵过程中动力学速率的算法。该算法仅利用在线测量的氧化还原电位来完成其任务。该程序包括一个将氧化还原电位与乙醇和生物质浓度相关联的人工神经网络（ANN）。然后，一个基于非线性观测器的算法使用生物质估计值来推断该发酵过程的动力学速率。该方法表明，氧化还原电位是梅斯卡尔发酵过程中微生物代谢活动的有价值指标。此外，估计的动力学速率可以被视为该过程中存在混合培养生长的直接证据。在本工作中，我们介绍了软件传感器的详细设计，以及其在实验室水平上的实验应用。
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English: We construct and discuss a toy model of the population of numerous
non-identical extragalactic sources of ultra-high-energy cosmic rays. In the
model, cosmic-ray particles are accelerated in magnetospheres of supermassive
black holes in galactic nuclei, the key parameter of acceleration being the
black-hole mass. We use astrophysical data on the redshift-dependent black-hole
mass function to describe the population of these cosmic-ray accelerators, from
weak to powerful, and confront the model with cosmic-ray data.
Chinese: 我们构建并讨论了一个模拟模型，用以描述众多非同质性超高层宇宙射线外星系源的人口。在模型中，宇宙射线粒子在星系核内超大质量黑洞的磁球中加速，加速的关键参数是黑洞的质量。我们利用关于红移依赖的黑洞质量函数的天文数据来描述这些宇宙射线加速器的分布，从弱到强，并将模型与宇宙射线数据进行对比。
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English: A plane topological graph $G=(V,E)$ is a graph drawn in the plane whose
vertices are points in the plane and whose edges are simple curves that do not
intersect, except at their endpoints. Given a plane topological graph $G=(V,E)$
and a set $C_G$ of parity constraints, in which every vertex has assigned a
parity constraint on its degree, either even or odd, we say that $G$ is
\emph{topologically augmentable} to meet $C_G$ if there exits a plane
topological graph $H$ on the same set of vertices, such that $G$ and $H$ are
edge-disjoint and their union is a plane topological graph that meets all
parity constraints.
In this paper, we prove that the problem of deciding if a plane topological
graph is topologically augmentable to meet parity constraints is
$\mathcal{NP}$-complete, even if the set of vertices that must change their
parities is $V$ or the set of vertices with odd degree. In particular, deciding
if a plane topological graph can be augmented to a Eulerian plane topological
graph is $\mathcal{NP}$-complete. Analogous complexity results are obtained,
when the augmentation must be done by a plane topological perfect matching
between the vertices not meeting their parities.
We extend these hardness results to planar graphs, when the augmented graph
must be planar, and to plane geometric graphs (plane topological graphs whose
edges are straight-line segments). In addition, when it is required that the
augmentation is made by a plane geometric perfect matching between the vertices
not meeting their parities, we also prove that this augmentation problem is
$\mathcal{NP}$-complete for plane geometric trees and paths.
For the particular family of maximal outerplane graphs, we characterize
maximal outerplane graphs that are topological augmentable to satisfy a set of
parity constraints.
Chinese: 一个平面拓扑图 $G=(V,E)$ 是在平面上绘制的一个图，其顶点是平面上的点，其边是简单的曲线，除了在端点处外，这些曲线不相交。给定一个平面拓扑图 $G=(V,E)$ 和一个集合 $C_G$，其中每个顶点都分配了一个关于其度数的奇偶性约束，要么是偶数，要么是奇数，我们说 $G$ 可以通过拓扑扩展来满足 $C_G$，如果存在一个在同一组顶点上的平面拓扑图 $H$，使得 $G$ 和 $H$ 是边不交的，并且它们的并集是一个满足所有奇偶性约束的平面拓扑图。
在本文中，我们证明了判断一个平面拓扑图是否可以通过拓扑扩展来满足奇偶性约束的问题是一个 $\mathcal{NP}$-完全问题，即使必须改变奇偶性的顶点集是 $V$ 或奇度顶点集。特别是，判断一个平面拓扑图是否可以被扩展为一个欧拉平面拓扑图是一个 $\mathcal{NP}$-完全问题。当扩展必须通过不满足奇偶性的顶点之间的平面拓扑完美匹配来完成时，也获得了类似的复杂性结果。
我们将这些困难结果扩展到平面图，当扩展的图必须是平面图时，以及到平面几何图（边是直线段的平面拓扑图）。此外，当要求通过不满足奇偶性的顶点之间的平面几何完美匹配来完成扩展时，我们也证明了对于平面几何树和路径，这个扩展问题也是 $\mathcal{NP}$-完全的。
对于特定的最大外平面图家族，我们描述了可以拓扑扩展以满足一组奇偶性约束的最大外平面图。
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English: We evaluate all split helicity gluon tree amplitudes in open twistor string
theory. We show that these amplitudes satisfy the BCFW recurrence relations
restricted to the split helicity case and, hence, that these amplitudes agree
with those of gauge theory. To do this we make a particular choice of the
sextic constraints in the link variables that determine the poles contributing
to the contour integral expression for the amplitudes. Using the residue
theorem to re-express this integral in terms of contributions from poles at
rational values of the link variables, which we determine, we evaluate the
amplitudes explicitly, regaining the gauge theory results of Britto et al.
Chinese: 我们评估了开放扭结弦理论中所有分裂螺旋性胶子树图振幅。我们表明，这些振幅满足仅限于分裂螺旋性情况的BCFW递归关系，因此，这些振幅与规范理论中的振幅一致。为此，我们在链变量中做出特定的六次约束选择，这些约束决定了贡献于振幅轮廓积分表达式的极点。利用留数定理将此积分重新表示为来自链变量有理值处的极点贡献，我们确定这些贡献，并显式地评估了振幅，从而恢复了Britto等人关于规范理论的结果。
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English: The existence of two metrics in massive gravity theories in principle allows
solutions where there are singularities in new scalar invariants jointly
constructed from them. These configurations occur when the two metrics differ
substantially from each other, as in black hole and cosmological solutions. The
simplest class of such singularities are determinant singularities. We
investigate whether the dynamics of bimetric massive gravity -- where the
second metric is allowed to evolve jointly with the spacetime metric -- can
avoid these singularities. We investigate whether the dynamics of bimetric
massive gravity, where the second metric is allowed to evolve jointly with the
spacetime metric, averts the simplest class of such singularities, namely
determinant singularities. We show that it is still possible to specify
non-singular initial conditions that evolve to a determinant singularity.
Determinant singularities are a feature of massive gravity of both fixed and
dynamical metric type.
Chinese: 大规模引力理论中存在两个度规，原则上允许存在由它们共同构造的新标量不变量中的奇点解。这些配置发生在两个度规彼此差异显著的情况下，如在黑洞和宇宙学解中。这类奇点的最简单类别是行列式奇点。我们研究双度规大规模引力动力学——其中第二个度规被允许与时空度规共同演化——是否可以避免这些奇点。我们研究双度规大规模引力动力学，其中第二个度规被允许与时空度规共同演化，是否避免了这类奇点的最简单类别，即行列式奇点。我们表明，仍然可以指定非奇点初始条件，这些条件会演化到行列式奇点。行列式奇点是固定和动态度规类型的大规模引力的一个特征。
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English: We present near-infrared VLT ISAAC imaging and spectroscopy of the peculiar
Virgo galaxy NGC 4438, whose nucleus has been classified as a LINER. The data
are supplemented by mid-infrared imaging, and compared to previous WFPC2 HST
broadband images. Images and position-velocity maps of the [Fe II] and H2 line
emissions are presented and compared with the distribution of the optical
narrow-line region and radio features. Our results show that shocks (possibly
driven by a radio jet) contribute to an important fraction of the excitation of
[Fe II], while X-ray heating from a central AGN may be responsible for the H2
excitation. We address the question whether the outflow has an AGN or a
starburst origin by providing new estimates of the central star formation rate
and the kinetic energy associated with the gas. By fitting a Sersic bulge, an
exponential disc and a compact nuclear source to the light distribution, we
decomposed NGC 4438's light distribution and found an unresolved nuclear source
at 0.8 arcsec resolution with M_K = -18.7 and J-H = 0.69. Our measured bulge
velocity dispersion, 142 km/s, together with the standard M_bh-sigma relation,
suggests a central black hole mass of log(M_bh/Msun) ~ 7.0. The stellar
kinematics measured from the near-infrared CO lines shows a strong peak in the
velocity dispersion of 178 km/s in the central 0.5 arcsec, which is possible
kinematic evidence of a central black hole. We calculated a general expression
for the integrated Sersic profile flux density in elliptical geometry,
including the case of 'disky' isophotes.
Chinese: 我们展示了近红外VLT ISAAC对奇特的 Virgo 星系 NGC 4438 的成像和光谱学观测，其核心已被归类为 LINER。数据得到了中红外成像的补充，并与之前的 WFPC2 HST 宽带图像进行了比较。展示了 [Fe II] 和 H2 线发射的图像和位置-速度图，并与光学窄线区分布和射电特征进行了比较。我们的结果表明，冲击（可能由射电喷流驱动）对 [Fe II] 激发的重要部分做出了贡献，而来自中心活动星系核的 X 射线加热可能负责 H2 的激发。我们通过提供中心星形成率和与气体相关的动能的新估计，来探讨喷流是否具有活动星系核或恒星爆发起源的问题。通过将塞里克隆起、指数盘和紧凑核源拟合到光分布，我们分解了 NGC 4438 的光分布，并在 0.8 角秒的分辨率下发现了一个未解的核源，其 M_K = -18.7 和 J-H = 0.69。我们测量的隆起速度分散度为 142 km/s，结合标准的 M_bh-σ 关系，表明中心黑洞质量为 log(M_bh/Msun) ~ 7.0。从近红外 CO 线测量的恒星动力学显示出在中心 0.5 角秒处的速度分散度有一个强烈的峰值，178 km/s，这可能是中心黑洞的动力学证据。我们计算了椭圆几何中综合塞里克轮廓光密度的一般表达式，包括“盘状”等值线的情形。
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English: In this note, we comment on the path integral formulation of string theory on
$\mathcal{M}\times\text{S}^3\times\mathbb{T}^4$ where $\mathcal{M}$ is any
hyperbolic 3-manifold. In the special case of $k=1$ NS-NS flux, we provide a
covariant description of the worldsheet theory and argue that the path integral
depends only on the details of the conformal boundary $\partial\mathcal{M}$,
making the background independence of this theory manifest. We provide a simple
path integral argument that the path integral localizes onto holomorphic
covering maps from the worldsheet to the boundary. For closed manifolds
$\mathcal{M}$, the gravitational path integral is argued to be trivial. This
implies that the bulk gravitational theory has precisely one state in its
Hilbert space. Finally, we comment on the effect of continuous deformations of
the worldsheet theory which introduce non-minimal string tension.
Chinese: 在这篇笔记中，我们讨论了在 $\mathcal{M}\times\text{S}^3\times\mathbb{T}^4$ 上的弦理论路径积分公式，其中 $\mathcal{M}$ 是任何双曲三维流形。在 $k=1$ 的NS-NS通量特殊情况中，我们提供了世界sheet理论的协变描述，并论证路径积分只依赖于共形边界 $\partial\mathcal{M}$ 的细节，使得该理论的背景独立性变得明显。我们提供了一个简单的路径积分论证，表明路径积分局部化到从世界sheet到边界的全纯覆盖映射。对于封闭流形 $\mathcal{M}$，论证了引力路径积分是平凡的。这意味着 bulk 引力理论在其希尔伯特空间中恰好有一个状态。最后，我们讨论了世界sheet理论连续变形的影响，这些变形引入了非最小弦张力。
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English: Since the start of its national renaissance in 1970, the Sultanate of Oman
(Oman) has gone over a major development in several areas, such as education,
infrastructure, and urbanization. This has been powered by the revenues from
exporting crude oil and natural gas, which together form the skeleton of the
country's economy. In the second half of 2014, the oil prices declined strongly
to about 50% of its price. This was followed by another moderate decline in the
second half of 2015 and the beginning of 2016, leaving the barrel price at a
low level below 30 US$ in January 2016 (as compared to above 110 US$ in June
2014). This drop had direct impacts on the economy of Oman, manifested in a
large budget deficit, reduced governmental expenditure, reduced or cancelled
subsidy of fuels and electricity, increase in the water tariff, and decline in
deposits in banks. The country is coping with this through its 9th five-year
plan (2016-2020), which adopts a strategy of diversifying the income and
relying less on the traditional oil and gas sector. The country has also taken
measures to facilitate private businesses. This article sheds light on these
topics as well as miscellaneous data about Oman.
Chinese: 自1970年开始其国家复兴以来，阿曼苏丹国（阿曼）在多个领域取得了重大发展，如教育、基础设施和城市化。这得益于出口原油和天然气的收入，这两者共同构成了国家经济的基础。2014年下半年，油价大幅下跌，降至其价格的约50%。随后在2015年下半年和2016年初，油价又出现了一次温和的下跌，使得2016年1月的桶装油价低于30美元（相比之下，2014年6月的价格高于110美元）。这一下跌对阿曼经济产生了直接影响，表现为巨额预算赤字、政府支出减少、燃料和电力的补贴减少或取消、水费上涨以及银行存款下降。该国正通过其第九个五年计划（2016-2020年）来应对这一挑战，该计划采用多元化收入来源的策略，减少对传统石油和天然气行业的依赖。该国还采取了措施来促进私营企业的发展。本文将探讨这些话题以及有关阿曼的一些杂项数据。
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English: The blends and hybrid nanocomposites of polypropylene - cycloolefin copolymer
were prepared by a twin-screw extruder followed by microfibril formation using
a single screw extruder. The effects of shear rate and organoclay on the
morphology of polypropylene - cycloolefin copolymer (PP/COC - 80/20 wt. %)
blends were studied by using a combination of rheological measurements, X-ray
diffraction (XRD) and scanning electron microscopy (SEM). It was found that
although the viscosity ratio of PP/COC blend was unfavorable for COC droplet
deformation, the COC phase was converted to finely dispersed fibrils in PP
matrix. This could be asserted to the high elasticity of the COC droplets that
suppressed the droplet breakup in the favor of fibrillation process. The high
glass transition temperature of COC (140 degree centigrade) could also assist
restoring the generated microfibril morphology upon cooling. The experimental
results also depicted that the droplet deformation and microfibril formation of
PP/COC/organoclay nanocomposites mainly depend on the organoclay partitioning,
which could be controlled predominantly by kinetic parameters. While the
localization of organoclay in the PP matrix resulted in smaller COC droplets
and fibrils with smaller diameter, the presence of organoclay inside COC
droplets reduced the droplet deformability, leading to fibrils with larger
diameter.
Chinese: 通过双螺杆挤出机制备了聚丙烯-环烯烃共聚物的混合物和杂化纳米复合材料，随后使用单螺杆挤出机制备微纤维。通过结合流变测量、X射线衍射（XRD）和扫描电子显微镜（SEM）研究了剪切速率和有机粘土对聚丙烯-环烯烃共聚物（PP/COC - 80/20 wt. %）混合物形态的影响。研究发现，尽管PP/COC混合物的粘度比不利于COC液滴变形，但COC相在PP基体中转化为细分散的纤维。这可以归因于COC液滴的高弹性，它抑制了液滴破碎，有利于纤维化过程。COC的高玻璃化转变温度（140摄氏度）也有助于在冷却时恢复生成的微纤维形态。实验结果还表明，PP/COC/有机粘土纳米复合材料的液滴变形和微纤维形成主要取决于有机粘土的分配，这主要可以通过动力学参数来控制。当有机粘土在PP基体中定位时，会导致COC液滴和直径较小的纤维，而有机粘土在COC液滴中的存在则降低了液滴的变形性，导致直径较大的纤维。
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English: Autonomous driving algorithms rely heavily on learning-based models, which
require large datasets for training. However, there is often a large amount of
redundant information in these datasets, while collecting and processing these
datasets can be time-consuming and expensive. To address this issue, this paper
proposes the concept of an active data-collecting strategy. For high-quality
data, increasing the collection density can improve the overall quality of the
dataset, ultimately achieving similar or even better results than the original
dataset with lower labeling costs and smaller dataset sizes. In this paper, we
design experiments to verify the quality of the collected dataset and to
demonstrate this strategy can significantly reduce labeling costs and dataset
size while improving the overall quality of the dataset, leading to better
performance of autonomous driving systems. The source code implementing the
proposed approach is publicly available on
https://github.com/Th1nkMore/carla_dataset_tools.
Chinese: 自动驾驶算法高度依赖于基于学习的模型，这些模型需要大量数据集进行训练。然而，这些数据集中往往存在大量冗余信息，而收集和处理这些数据集可能既耗时又昂贵。为了解决这个问题，本文提出了主动数据收集策略的概念。对于高质量数据，增加收集密度可以提高数据集的整体质量，最终在降低标注成本和数据集规模的情况下，达到与原始数据集相似甚至更好的结果。在本文中，我们设计了实验来验证收集到的数据集的质量，并证明这种策略可以显著降低标注成本和数据集规模，同时提高数据集的整体质量，从而提升自动驾驶系统的性能。实现所提出方法的源代码可在https://github.com/Th1nkMore/carla_dataset_tools上公开获取。
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