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English: Indium gallium nitride films with nanocolumnar microstructure were deposited
with varying indium content and substrate temperatures using plasma-enhanced
evaporation on amorphous SiO2 substrates. FESEM and XRD results are presented,
showing that more crystalline nanocolumnar microstructures can be engineered at
lower indium compositions. Nanocolumn diameter and packing factor (void
fraction) was found to be highly dependent on substrate temperature, with
thinner and more closely packed nanocolumns observed at lower substrate
temperatures.
Chinese: 在非晶态SiO2衬底上，通过等离子体增强蒸发，以不同的铟含量和衬底温度沉积了具有纳米柱状微观结构的氮化镓铟薄膜。FESEM和XRD结果如下所示，表明在较低的铟含量下可以设计出更多结晶的纳米柱状微观结构。研究发现，纳米柱直径和填充因子（空隙率）高度依赖于衬底温度，在较低的衬底温度下观察到更细且更紧密排列的纳米柱。
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English: Measurements of the radius and limb brightening of the Sun provide important
information about the solar atmosphere structure and temperature. The solar
radius increases as the observation at radio frequency decreases, indicating
that each emission originates higher in the atmosphere. Thus, different layers
of the solar atmosphere can be probed by observing at multiple wavelengths. In
this work, we determined the average radius and limb brightening at 100, 212,
230, and 405 GHz, using data from the Solar Submillimeter Telescope and ALMA's
single-dish observations. For the first time, limb brightening values for
frequencies of 212 and 405 GHz were estimated. At sub-THz frequencies, the
observed limb brightening may affect the solar radius measurements. We use two
different and well known approaches to determine the radius: the half-power
method and the inflection-point method. We investigate how the antenna beam
size and the limb brightening level, LB, can affect the radius measurements
using both methods. Our results showed that the inflection-point method is the
least affected by these parameters, and should thus be used for solar radius
estimates at radio wavelengths. The measured average radii are 968"~$\pm$~3"
(100 GHz), 963"~$\pm$~3" (212 GHz), 963"~$\pm$~2" (230 GHz), and 963"~$\pm$~5"
(405 GHz). Finally, we used forward modeling to estimate the ranges of LB of
the solar disk resulting in 5%-19% (100 GHz), 2%-12% (212 GHz), 6%-18% (230
GHz), and 3%-17% (405 GHz). Both radius and limb brightening estimates agree
with previous measurements reported in the literature.
Chinese: 太阳半径和边缘亮度的测量提供了关于太阳大气结构温度的重要信息。随着无线电频率的观测降低，太阳半径增加，表明每种辐射都起源于大气层较高处。因此，可以通过观察多个波长来探测太阳大气的不同层。在这项工作中，我们使用太阳亚毫米望远镜和ALMA的单天线观测数据，确定了100、212、230和405 GHz的平均半径和边缘亮度。首次估计了212和405 GHz频率的边缘亮度值。在亚太赫兹频率下，观测到的边缘亮度可能影响太阳半径的测量。我们使用两种不同且已知的方法来确定半径：半功率法和拐点法。我们调查了天线波束大小和边缘亮度水平（LB）如何影响这两种方法的半径测量。我们的结果表明，拐点法受这些参数影响最小，因此应用于无线电波长的太阳半径估计。测量的平均半径分别为968"~$\pm$~3"（100 GHz）、963"~$\pm$~3"（212 GHz）、963"~$\pm$~2"（230 GHz）和963"~$\pm$~5"（405 GHz）。最后，我们使用正向建模来估计导致5%-19%（100 GHz）、2%-12%（212 GHz）、6%-18%（230 GHz）和3%-17%（405 GHz）的边缘亮度（LB）范围。半径和边缘亮度的估计与文献中报道的先前测量结果一致。
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English: Accurate photometric redshifts are among the key requirements for precision
weak lensing measurements. Both the large size of the Sloan Digital Sky Survey
(SDSS) and the existence of large spectroscopic redshift samples that are
flux-limited beyond its depth have made it the optimal data source for
developing methods to properly calibrate photometric redshifts for lensing.
Here, we focus on galaxy-galaxy lensing in a survey with spectroscopic lens
redshifts, as in the SDSS. We develop statistics that quantify the effect of
source redshift errors on the lensing calibration and on the weighting scheme,
and show how they can be used in the presence of redshift failure and sampling
variance. We then demonstrate their use with 2838 source galaxies with
spectroscopy from DEEP2 and zCOSMOS, evaluating several public photometric
redshift algorithms, in two cases including a full p(z) for each object, and
find lensing calibration biases as low as 1% (due to fortuitous cancellation of
two types of bias) or as high as 20% for methods in active use (despite the
small mean photoz bias of these algorithms). Our work demonstrates that
lensing-specific statistics must be used to reliably calibrate the lensing
signal, due to asymmetric effects of (frequently non-Gaussian) photoz errors.
We also demonstrate that large-scale structure (LSS) can strongly impact the
photoz calibration and its error estimation, due to a correlation between the
LSS and the photoz errors, and argue that at least two independent degree-scale
spectroscopic samples are needed to suppress its effects. Given the size of our
spectroscopic sample, we can reduce the galaxy-galaxy lensing calibration error
well below current SDSS statistical errors.
Chinese: 精确的光度红移是进行高精度弱引力透镜测量的关键要求。斯隆数字巡天（SDSS）的大规模以及存在大量光谱红移样本，这些样本在SDSS深度之外都是光通量有限的，这使得它成为开发适当校准透镜光度红移方法的最优数据来源。在这里，我们专注于具有光谱透镜红移的调查中的星系-星系透镜效应，如SDSS。我们开发了统计方法，用于量化源红移误差对透镜校准和加权方案的影响，并展示了如何在存在红移失败和采样方差的情况下使用它们。然后，我们使用来自DEEP2和zCOSMOS的2838个源星系的光谱数据来展示它们的使用，评估了几个公共光度红移算法，在两种情况下包括每个对象的全p(z)，并发现透镜校准偏差低至1%（由于两种类型偏差的偶然抵消）或高达20%（尽管这些算法的平均光度红移偏差很小）。我们的工作表明，由于光度红移误差（通常是非高斯分布）的非对称效应，必须使用透镜特定的统计方法来可靠地校准透镜信号。我们还展示了由于大规模结构（LSS）与光度红移误差之间的相关性，大规模结构可以强烈影响光度红移校准及其误差估计，并认为至少需要两个独立的度规尺度的光谱样本来抑制其影响。鉴于我们光谱样本的大小，我们可以将星系-星系透镜校准误差降低到当前SDSS统计误差以下。
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English: A procedure to include the uncertainty on the background estimate for upper
limit calculations using Poissonian sampling is presented for the case where a
Gaussian assumption on the uncertainty can be made. Under that hypothesis an
analytic expression of the likelihood is derived which can be written in terms
of polynomials defined by recursion. This expression may lead to a significant
speed up of computing applications that extract the upper limits using Toy
Monte Carlo.
Chinese: 针对在背景估计的不确定性可以假设为高斯分布的情况下，提出了一种使用泊松采样包括不确定性的上限计算程序。在该假设下，推导出似然函数的解析表达式，该表达式可以用递归定义的多项式来表示。这种表达式可能显著加快使用Toy Monte Carlo提取上限的计算应用的速度。
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English: A prevalent assumption regarding real-world data is that it lies on or close
to a low-dimensional manifold. When deploying a neural network on data
manifolds, the required size, i.e., the number of neurons of the network,
heavily depends on the intricacy of the underlying latent manifold. While
significant advancements have been made in understanding the geometric
attributes of manifolds, it's essential to recognize that topology, too, is a
fundamental characteristic of manifolds. In this study, we investigate network
expressive power in terms of the latent data manifold. Integrating both
topological and geometric facets of the data manifold, we present a size upper
bound of ReLU neural networks.
Chinese: 关于真实世界数据的普遍假设是它位于或接近低维流形上。当在数据流形上部署神经网络时，所需的规模，即网络神经元数量，很大程度上取决于底层潜在流形的复杂性。虽然已经在理解流形的几何属性方面取得了重大进展，但必须认识到拓扑也是流形的基本特征之一。在本研究中，我们基于潜在数据流形研究神经网络的表示能力。通过整合数据流形的拓扑和几何特性，我们提出了ReLU神经网络的规模上限。
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English: During the late stages of gravitational core-collapse of massive stars,
extreme isospin asymmetries are reached within the core. Due to the lack of
microscopic calculations of electron capture (EC) rates for all relevant
nuclei, in general simple analytic parameterizations are employed. We study
here several extensions of these parameterizations, allowing for a temperature,
electron density and isospin dependence as well as for odd-even effects. The
latter extra degrees of freedom considerably improve the agreement with large
scale microscopic rate calculations. We find, in particular, that the isospin
dependence leads to a significant reduction of the global EC rates during core
collapse with respect to fiducial results, where rates optimized on
calculations of stable $fp$-shell nuclei are used. Our results indicate that
systematic microscopic calculations and experimental measurements in the
$N\approx 50$ neutron rich region are desirable for realistic simulations of
the core-collapse.
Chinese: 在质量大恒星引力核心坍缩的晚期阶段，核心内部达到极端的同位旋不均匀性。由于缺乏所有相关核的电子俘获（EC）速率的微观计算，通常采用简单的解析参数化。在此，我们研究了这些参数化的几个扩展，允许温度、电子密度和同位旋的依赖性，以及奇偶效应。后者额外的自由度显著提高了与大规模微观速率计算的吻合度。我们发现，特别是同位旋的依赖性导致在核心坍缩期间全局EC速率相对于基准结果有显著降低，其中使用了优化于稳定$fp$壳层核的计算速率。我们的结果表明，在$N\approx 50$的中子富集区域进行系统的微观计算和实验测量对于现实的核心坍缩模拟是必要的。
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English: It is important for machines to interpret human emotions properly for better
human-machine communications, as emotion is an essential part of human-to-human
communications. One aspect of emotion is reflected in the language we use. How
to represent emotions in texts is a challenge in natural language processing
(NLP). Although continuous vector representations like word2vec have become the
new norm for NLP problems, their limitations are that they do not take emotions
into consideration and can unintentionally contain bias toward certain
identities like different genders.
This thesis focuses on improving existing representations in both word and
sentence levels by explicitly taking emotions inside text and model bias into
account in their training process. Our improved representations can help to
build more robust machine learning models for affect-related text
classification like sentiment/emotion analysis and abusive language detection.
We first propose representations called emotional word vectors (EVEC), which
is learned from a convolutional neural network model with an emotion-labeled
corpus, which is constructed using hashtags. Secondly, we extend to learning
sentence-level representations with a huge corpus of texts with the pseudo task
of recognizing emojis. Our results show that, with the representations trained
from millions of tweets with weakly supervised labels such as hashtags and
emojis, we can solve sentiment/emotion analysis tasks more effectively.
Lastly, as examples of model bias in representations of existing approaches,
we explore a specific problem of automatic detection of abusive language. We
address the issue of gender bias in various neural network models by conducting
experiments to measure and reduce those biases in the representations in order
to build more robust classification models.
Chinese: 对于机器正确理解人类情感以实现更好的人机交流来说，情感是人类人际交流的重要组成部分。情感的一个方面体现在我们所使用的语言中。如何在文本中表达情感是自然语言处理（NLP）中的一个挑战。尽管连续向量表示，如word2vec，已成为NLP问题的标准，但它们的局限性在于没有考虑情感因素，并且可能无意中包含对某些身份（如不同性别）的偏见。
本论文重点关注通过在训练过程中显式考虑文本中的情感和模型偏见来改进词和句子层面的现有表示。我们改进的表示可以帮助构建更鲁棒的机器学习模型，用于情感相关的文本分类，如情感/情绪分析和侮辱性语言检测。
我们首先提出了名为情感词向量（EVEC）的表示方法，它通过一个带有情感标签的语料库从卷积神经网络模型中学习而来，该语料库是通过使用标签构建的。其次，我们扩展到使用大量文本语料库学习句子级表示，这些文本语料库的伪任务是识别表情符号。我们的结果表明，通过从数百万条带有弱监督标签（如标签和表情符号）的推文中训练的表示，我们可以更有效地解决情感/情绪分析任务。
最后，作为现有方法中表示模型偏差的例子，我们探讨了自动检测侮辱性语言的具体问题。我们通过实验来测量和减少各种神经网络模型中的性别偏见问题，以构建更鲁棒的分类模型。
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English: A large number and diversity of techniques have been offered in the
literature in recent years for solving multi-label classification tasks,
including classifier chains where predictions are cascaded to other models as
additional features. The idea of extending this chaining methodology to
multi-output regression has already been suggested and trialed: regressor
chains. However, this has so-far been limited to greedy inference and has
provided relatively poor results compared to individual models, and of limited
applicability. In this paper we identify and discuss the main limitations,
including an analysis of different base models, loss functions, explainability,
and other desiderata of real-world applications. To overcome the identified
limitations we study and develop methods for regressor chains. In particular we
present a sequential Monte Carlo scheme in the framework of a probabilistic
regressor chain, and we show it can be effective, flexible and useful in
several types of data. We place regressor chains in context in general terms of
multi-output learning with continuous outputs, and in doing this shed
additional light on classifier chains.
Chinese: 近年来，文献中提出了大量多样化的技术来解决多标签分类任务，包括分类链，其中预测被作为额外特征传递给其他模型。将这种链式方法扩展到多输出回归已经有所建议并进行了试验：回归链。然而，迄今为止这仅限于贪婪推理，并且与单独模型相比提供了相对较差的结果，且适用性有限。在本文中，我们识别并讨论了主要的局限性，包括不同基础模型、损失函数、可解释性以及实际应用中的其他需求的分析。为了克服这些已识别的局限性，我们研究并开发了回归链的方法。特别是我们提出了一种在概率回归链框架下的顺序蒙特卡洛方案，并证明它可以是有效的、灵活的，并且在多种类型的数据中都是有用的。我们将回归链置于多输出学习（具有连续输出）的一般背景下进行讨论，通过这种方式，我们还对分类链进行了进一步的阐述。
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English: The persistent increases in spin-down rate offsets seen to accompany glitches
in the Crab and other pulsars suggest increases in the spin-down torque. We
interpret these offsets as due to starquakes occurring as the star spins down
and the rigid crust becomes less oblate. We study the evolution of strain in
the crust, the initiation of starquakes, and possible consequences for magnetic
field and torque evolution. Crust cracking occurs as equatorial material shears
under the compressive forces arising from the star's decreasing circumference,
and matter moves to higher latitudes along a fault inclined to the equator. A
starquake is most likely to originate near one of the two points on the
rotational equator farthest from the magnetic poles. The material breaks along
a fault approximately aligned with the magnetic poles. We suggest that the
observed offsets come about when a starquake perturbs the star's mass
distribution, producing a misalignment of the angular momentum and spin axes.
Subsequently, damped precession to a new rotational state increases the angle
alpha between the rotation and magnetic axes. The resulting increase in
external torque appears as a permanent increase in the spin-down rate. Repeated
starquakes would continue to increase alpha, making the pulsar more of an
orthogonal rotator.
Chinese: 持续增加的减旋速率偏移似乎伴随着蟹星和其他脉冲星的故障，这表明减旋扭矩的增加。我们将这些偏移解释为由于恒星减旋时发生的星震，以及刚性地壳变得不那么扁平。我们研究了地壳应变的演化、星震的起始以及可能对磁场和扭矩演化的后果。地壳开裂发生在赤道物质在恒星减小周长产生的压缩力作用下发生剪切，物质沿着倾向赤道的断层向高纬度移动。星震最有可能起源于旋转赤道上的两个点之一，这两个点距离磁极最远。材料沿着与磁极大致对齐的断层断裂。我们建议，观察到的偏移是由于星震扰动恒星的质心分布，导致角动量和自转轴的不对齐。随后，阻尼进动到新的旋转状态增加了旋转轴和磁场轴之间的角度α。由此引起的外部扭矩的增加表现为减旋速率的永久性增加。重复的星震会继续增加α，使脉冲星更像一个正交旋转体。
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English: A tight non-linear relation exists between the X-ray and UV emission in
quasars (i.e. $L_{\rm X}\propto L_{\rm UV}^{\gamma}$), with a dispersion of
$\sim$0.2~dex over $\sim$3~orders of magnitude in luminosity. Here we propose a
modified version of this relation which involves the broad emission lines'
full-width at half maximum, $L_{\rm X}\propto L_{\rm
UV}^{\hat\gamma}\upsilon_{\rm fwhm}^{\hat\beta}$. We interpret this new
relation through a simple, {\it ad-hoc} model of accretion disc corona, derived
from previous works where it is assumed that reconnection and magnetic loops
above the accretion disc can account for the production of the primary X-ray
radiation. We find that the monochromatic optical-UV (2500 \AA) and X-ray (2
keV) luminosities depend on the black hole mass and accretion rate as $L_{\rm
UV}\propto M_{\rm BH}^{4/3} (\dot{M}/\dot{M}_{\rm Edd})^{2/3}$ and $L_{\rm
X}\propto M_{\rm BH}^{19/21} (\dot{M}/\dot{M}_{\rm Edd})^{5/21}$, respectively.
Assuming a broad line region size function of the disc luminosity $R_{\rm
blr}\propto L_{\rm disc}^{0.5}$ we finally have that $L_{\rm X}\propto L_{\rm
UV}^{4/7} \upsilon_{\rm fwhm}^{4/7}$. Such relation is remarkably consistent
with the slopes and the normalization obtained from a fit of a sample of 545
optically selected quasars from SDSS DR7 cross matched with the latest
XMM-Newton catalogue 3XMM-DR6. The homogeneous sample used here has a
dispersion of 0.21 dex, which is much lower than previous works in the
literature and suggests a tight physical relation between the accretion disc
and the X-ray emitting corona. The proposed new relation does not evolve with
time, and thus it can be employed as a cosmological indicator to robustly
estimate cosmological parameters.
Chinese: 在类星体中，X射线和紫外发射之间存在紧密的非线性关系（即 $L_{\rm X}\propto L_{\rm UV}^{\gamma}$），其光度在约3个数量级范围内具有约0.2个dex的离散度。在此，我们提出该关系的改进版本，该版本涉及宽发射线的半峰全宽，即 $L_{\rm X}\propto L_{\rm UV}^{\hat\gamma}\upsilon_{\rm fwhm}^{\hat\beta}$。我们通过一个简单的、{\it ad-hoc}的吸积盘冠层模型来解释这一新关系，该模型基于先前的研究，其中假设吸积盘上方的重联和磁环可以解释初级X射线的产生。我们发现，单色光学-紫外（2500 \AA）和X射线（2 keV）光度分别依赖于黑洞质量和吸积率，表现为 $L_{\rm UV}\propto M_{\rm BH}^{4/3} (\dot{M}/\dot{M}_{\rm Edd})^{2/3}$ 和 $L_{\rm X}\propto M_{\rm BH}^{19/21} (\dot{M}/\dot{M}_{\rm Edd})^{5/21}$。假设盘光度的宽线区尺度函数为 $R_{\rm blr}\propto L_{\rm disc}^{0.5}$，最终我们得到 $L_{\rm X}\propto L_{\rm UV}^{4/7} \upsilon_{\rm fwhm}^{4/7}$。这种关系与从SDSS DR7中选取的545个光学选择的类星体样本（与最新的XMM-Newton目录3XMM-DR6进行交叉匹配后拟合得到的斜率和归一化值）高度一致。这里使用的同质样本离散度为0.21 dex，远低于文献中的先前研究，表明吸积盘与X射线发射冠层之间存在紧密的物理关系。所提出的新关系不随时间变化，因此可以作为一种宇宙学指标，用于稳健地估计宇宙学参数。
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English: This is an overview of a formalisation project in the proof assistant
Isabelle/HOL of a number of research results in infinitary combinatorics and
set theory (more specifically in ordinal partition relations) by
Erd\H{o}s--Milner, Specker, Larson and Nash-Williams, leading to Larson's proof
of the unpublished result by E.C. Milner asserting that for all $m \in
\mathbb{N}$, $\omega^\omega\arrows(\omega^\omega, m)$. This material has been
recently formalised by Paulson and is available on the Archive of Formal
Proofs; here we discuss some of the most challenging aspects of the
formalisation process. This project is also a demonstration of working with
Zermelo-Fraenkel set theory in higher-order logic.
Chinese: 这是在证明助手 Isabelle/HOL 中对一系列由 Erdős--Milner、Specker、Larson 和 Nash-Williams 在超限组合学和集合论（更具体地说是序数划分关系）领域的研究成果进行形式化的项目概述，这些成果最终导致了 Larson 对 E.C. Milner 未发表的结果的证明，该结果断言对于所有 $m \in \mathbb{N}$，都有 $\omega^\omega\arrows(\omega^\omega, m)$。这些材料最近由 Paulson 进行了形式化，并在形式化证明档案库（Archive of Formal Proofs）上可用；在这里我们讨论了形式化过程中一些最具挑战性的方面。该项目也是使用策梅洛-弗兰克尔集合论在高阶逻辑中工作的一个示范。
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English: Bowman and Bradley obtained a remarkable formula among multiple zeta values.
The formula states that the sum of multiple zeta values for indices which
consist of the shuffle of two kinds of the strings $\{1,3,\ldots,1,3\}$ and
$\{2,\ldots,2\}$ is a rational multiple of a power of $\pi^2$. Recently, Saito
and Wakabayashi proved that analogous but more general sums of finite multiple
zeta values in an adelic ring $\mathcal{A}_1$ vanish. In this paper, we
partially lift Saito-Wakabayashi's theorem from $\mathcal{A}_1$ to
$\mathcal{A}_2$. Our result states that a Bowman-Bradley type sum of finite
multiple zeta values in $\mathcal{A}_2$ is a rational multiple of a special
element and this is closer to the original Bowman-Bradley theorem.
Chinese: 鲍文和布拉德利在多重泽塔值中得到了一个显著的公式。
该公式表明，由两种字符串 $\{1,3,\ldots,1,3\}$ 和 $\{2,\ldots,2\}$ 的错位组成的索引的多重泽塔值的和是 $\pi^2$ 的幂的理性倍数。最近，斉藤和若林证明了在代数数环 $\mathcal{A}_1$ 中，类似但更一般的多重泽塔值的有限和消失。在这篇论文中，我们将斉藤-若林的定理从 $\mathcal{A}_1$ 部分提升到 $\mathcal{A}_2$。我们的结果表明，在 $\mathcal{A}_2$ 中的鲍文-布拉德利类型的多重泽塔值的和是特殊元素的理性倍数，这更接近原始的鲍文-布拉德利定理。
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English: We introduce a procedure based on quantum expectation values of measurement
observables to characterize quantum coherence. Our measure allows one to
quantify coherence without having to perform tomography of the quantum state,
and can be directly calculated from measurement expectation values. This
definition of coherence allows the decomposition into contributions
corresponding to the non-classical correlations between the subsystems and
localized on each subsystem. The method can also be applied to cases where the
full set of measurement operators is unavailable. An estimator using the
truncated measurement operators can be used to obtain lower bound to the
genuine value of coherence. We illustrate the method for several bipartite
systems, and show the singular behavior of the coherence measure in a spin-1
chain, characteristic of a quantum phase transition.
Chinese: 我们介绍了一种基于测量可观测量量子期望值的程序，用于表征量子相干性。我们的度量方法允许人们在不需要对量子态进行全息术的情况下量化相干性，并且可以直接从测量期望值中计算出来。这种相干性的定义允许将相干性分解为对应于子系统之间非经典相关性和每个子系统局部化的贡献。该方法也可应用于测量算子全集不可用的情况。可以使用截断测量算子的估计器来获得相干性真实值的下界。我们为几个分体系统说明了这种方法，并展示了在自旋-1链中的相干性度量的奇异行为，这是量子相变的一个特征。
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English: Modern compression algorithms exploit complex structures that are present in
signals to describe them very efficiently. On the other hand, the field of
compressed sensing is built upon the observation that "structured" signals can
be recovered from their under-determined set of linear projections. Currently,
there is a large gap between the complexity of the structures studied in the
area of compressed sensing and those employed by the state-of-the-art
compression codes. Recent results in the literature on deterministic signals
aim at bridging this gap through devising compressed sensing decoders that
employ compression codes. This paper focuses on structured stochastic processes
and studies the application of rate-distortion codes to compressed sensing of
such signals. The performance of the formerly-proposed compressible signal
pursuit (CSP) algorithm is studied in this stochastic setting. It is proved
that in the very low distortion regime, as the blocklength grows to infinity,
the CSP algorithm reliably and robustly recovers $n$ instances of a stationary
process from random linear projections as long as their count is slightly more
than $n$ times the rate-distortion dimension (RDD) of the source. It is also
shown that under some regularity conditions, the RDD of a stationary process is
equal to its information dimension (ID). This connection establishes the
optimality of the CSP algorithm at least for memoryless stationary sources, for
which the fundamental limits are known. Finally, it is shown that the CSP
algorithm combined by a family of universal variable-length fixed-distortion
compression codes yields a family of universal compressed sensing recovery
algorithms.
Chinese: 现代压缩算法利用信号中存在的复杂结构来非常高效地描述它们。另一方面，压缩感知领域建立在对“结构化”信号可以从其欠定线性投影集中恢复的观察之上。目前，压缩感知领域研究的结构复杂性与现代压缩码所采用的复杂度之间存在巨大差距。近期文献中关于确定性信号的研究旨在通过设计采用压缩码的压缩感知解码器来弥合这一差距。本文重点关注结构化随机过程，并研究率失真码在此类信号的压缩感知中的应用。本文研究了先前提出的可压缩信号追踪（CSP）算法在该随机环境下的性能。证明在极低失真情况下，随着块长趋于无穷，只要投影数量略多于源信号的率失真维度（RDD）的n倍，CSP算法就能可靠且鲁棒地从随机线性投影中恢复n个平稳过程实例。此外，还表明在满足某些正则性条件下，平稳过程的RDD等于其信息维度（ID）。这种联系确立了CSP算法至少对于记忆less平稳源的最优性，已知这些源的基本极限。最后，本文表明，CSP算法与一族通用变长固定失真压缩码结合，可产生一族通用压缩感知恢复算法。
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English: In this article, we provide and overview of what we consider to be some of
the most pressing research questions facing the fields of artificial
intelligence (AI) and computational intelligence (CI); with the latter focusing
on algorithms that are inspired by various natural phenomena. We demarcate
these questions using five unique Rs - namely, (i) rationalizability, (ii)
resilience, (iii) reproducibility, (iv) realism, and (v) responsibility.
Notably, just as air serves as the basic element of biological life, the term
AIR5 - cumulatively referring to the five aforementioned Rs - is introduced
herein to mark some of the basic elements of artificial life (supporting the
sustained growth of AI and CI). A brief summary of each of the Rs is presented,
highlighting their relevance as pillars of future research in this arena.
Chinese: 在这篇文章中，我们概述了我们认为人工智能（AI）和计算智能（CI）领域面临的一些最紧迫的研究问题；后者专注于受各种自然现象启发的算法。我们使用五个独特的“R”来界定这些问题——即（i）合理性，（ii）韧性，（iii）可重复性，（iv）现实性和（v）责任。值得注意的是，正如空气是生物生命的基本元素一样，术语“AIR5”——累积指代上述五个“R”——在此被引入，以标记人工生命的一些基本元素（支持AI和CI的持续增长）。对每个“R”的简要总结被提出，突出它们作为该领域未来研究支柱的相关性。
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English: A representation of the perturbation series of a general functional measure
is given in terms of generalized Feynman graphs and -rules. The graphical
calculus is applied to certain functional measures of L\'evy type. A graphical
notion of Wick ordering is introduced and is compared with orthogonal
decompositions of the Wiener-It\^o-Segal type. It is also shown that the linked
cluster theorem for Feynman graphs extends to generalized Feynman graphs. We
perturbatively prove existence of the thermodynamic limit for the free energy
density and the moment functions. The results are applied to the gas of charged
microscopic or mesoscopic particles -- neutral in average -- in $d=2$
dimensions generating a static field $\phi$ with quadratic energy density
giving rise to a pair interaction. The pressure function for this system is
calculated up to fourth order. We also discuss the subtraction of
logarithmically divergent self-energy terms for a gas of only one particle type
by a local counterterm of first order.
Chinese: 一个一般泛函测度扰动级数的表示，用广义费曼图和规则给出。图形计算被应用于某些L\'evy类型的泛函测度。引入了Wick排序的图形概念，并将其与Wiener-It\^o-Segal类型的正交分解进行比较。还表明，费曼图的关联簇定理也适用于广义费曼图。我们通过微扰法证明了自由能密度和矩函数热力学极限的存在。这些结果应用于$ d=2 $维度的带电微观或介观粒子气体——平均中性——产生一个具有二次能量密度的静态场$\phi$，从而产生对偶相互作用。计算了该系统的压力函数到四阶。我们还讨论了通过一阶局部反项对仅有一种粒子类型的气体对数发散的自能项进行减除。
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English: We consider the spectrum of a $U(1)$ quantum link model where gauge fields
are realized as $S=1/2$ spins and demonstrate a new mechanism for generating
quantum many-body scars (high-energy eigenstates that violate the eigenstate
thermalization hypothesis) in a constrained Hilbert space. Many-body dynamics
with local constraints has attracted much attention due to the recent discovery
of non-ergodic behavior in quantum simulators based on Rydberg atoms. Lattice
gauge theories provide natural examples of constrained systems since physical
states must be gauge-invariant. In our case, the Hamiltonian $H={\cal O}_{\rm
kin}+\lambda {\cal O}_{\rm pot}$, where ${\cal O}_{\rm pot}$ (${\cal O}_{\rm
kin}$) is diagonal (off-diagonal) in the electric flux basis, contains exact
mid-spectrum zero modes at $\lambda=0$ whose number grows exponentially with
system size. This massive degeneracy is lifted at any non-zero $\lambda$ but
some special linear combinations that simultaneously diagonalize ${\cal O}_{\rm
kin}$ and ${\cal O}_{\rm pot}$ survive as quantum many-body scars, suggesting
an ``order-by-disorder'' mechanism in the Hilbert space. We give evidence for
such scars and show their dynamical consequences on two-leg ladders with up to
$56$ spins, which may be tested using available proposals of quantum
simulators. Results on wider ladders point towards their presence in two
dimensions as well.
Chinese: 我们考虑了一个 $U(1)$ 量子链模型的谱，其中规范场以 $S=1/2$ 自旋的形式实现，并在一个受约束的希尔伯特空间中展示了产生量子多体疤痕（违反本征态热化假设的高能本征态）的新机制。由于最近在基于里德伯原子的量子模拟器中发现了非遍历行为，具有局部约束的多体动力学引起了广泛关注。晶格规范理论提供了受约束系统的自然例子，因为物理状态必须是规范不变的。在我们的情况下，哈密顿量 $H={\cal O}_{\rm kin}+\lambda {\cal O}_{\rm pot}$，其中 ${\cal O}_{\rm pot}$（${\cal O}_{\rm kin}$）在电通量基中是对角线（非对角线）的，在 $\lambda=0$ 时包含精确的中谱零模，其数量随着系统尺寸的指数增长。这种大量简并性在任意非零 $\lambda$ 时被消除，但某些同时对角化 ${\cal O}_{\rm kin}$ 和 ${\cal O}_{\rm pot}$ 的特殊线性组合作为量子多体疤痕幸存下来，这表明希尔伯特空间中存在“无序产生秩序”的机制。我们为这些疤痕提供了证据，并展示了它们在最多有 $56$ 个自旋的两腿梯子上动态后果，这可以通过使用可用的量子模拟器方案进行测试。更宽的梯子上的结果指向它们在二维中也存在。
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English: We explore the use of the stochastic resolution-of-the-identity (sRI) with
the phaseless auxiliary-field quantum Monte Carlo (ph-AFQMC) method. sRI is
combined with four existing local energy evaluation strategies in ph-AFQMC,
namely (1) the half-rotated electron repulsion integral tensor (HR), (2)
Cholesky decomposition (CD), (3) tensor hypercontraction (THC), or (4) low-rank
factorization (LR). We demonstrate that HR-sRI achieves no scaling reduction,
CD-sRI scales as $\mathcal O(N^3)$, and THC-sRI and LR-sRI scale as $\mathcal
O(N^2)$, albeit with a potentially large prefactor. Furthermore, the
walker-specific extra memory requirement in CD is reduced from $\mathcal
O(N^3)$ to $\mathcal O(N^2)$ with sRI, while sRI-based THC and LR algorithms
lead to a reduction from $\mathcal O(N^2)$ extra memory to $\mathcal O(N)$.
Based on numerical results for one-dimensional hydrogen chains and water
clusters, we demonstrated that, along with the use of a variance reduction
technique, CD-sRI achieves cubic-scaling {\it without overhead}. In particular,
we find for the systems studied the observed scaling of standard CD is
$\mathcal O(N^{3-4})$ while for CD-sRI it is reduced to $\mathcal O(N^{2-3})$.
Once a memory bottleneck is reached, we expect THC-sRI and LR-sRI to be
preferred methods due to their quadratic-scaling memory requirements and their
quadratic-scaling of the local energy evaluation (with a potentially large
prefactor). The theoretical framework developed here should facilitate
large-scale ph-AFQMC applications that were previously difficult or impossible
to carry out with standard computational resources.
Chinese: 我们探索将随机解析化（sRI）与无相位辅助场量子蒙特卡罗（ph-AFQMC）方法结合使用。sRI与ph-AFQMC中的四个现有的局部能量评估策略相结合，即（1）半旋转电子排斥积分张量（HR），（2）Cholesky分解（CD），（3）张量超收缩（THC），或（4）低秩分解（LR）。我们证明，HR-sRI没有缩放减少，CD-sRI的缩放为$\mathcal O(N^3)$，而THC-sRI和LR-sRI的缩放为$\mathcal O(N^2)$，尽管可能存在一个大的预因子。此外，CD中的行特定的额外内存需求从$\mathcal O(N^3)$减少到$\mathcal O(N^2)$与sRI结合使用，而基于sRI的THC和LR算法将额外内存需求从$\mathcal O(N^2)$减少到$\mathcal O(N)$。基于一维氢链和水簇的数值结果，我们证明了，结合使用方差减少技术，CD-sRI实现了无额外开销的立方缩放。特别是，我们发现，对于所研究的系统，标准CD的观察到的缩放为$\mathcal O(N^{3-4})$，而CD-sRI的缩放减少到$\mathcal O(N^{2-3})$。一旦达到内存瓶颈，我们预期THC-sRI和LR-sRI将因其二次缩放的内存需求和局部能量评估的二次缩放（可能存在一个大的预因子）而成为首选方法。这里发展的理论框架应该促进ph-AFQMC的大规模应用，这些应用以前因标准计算资源而难以或不可能实现。
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English: Rust claims to advance industrial programming by bridging the gap between
low-level systems programming and high-level application programming. At the
heart of the argument that this enables programmers to build more reliable and
efficient software is the borrow checker - a novel approach to ownership that
aims to balance type system expressivity with usability. And yet, to date there
is no core type system that captures Rust's notion of ownership and borrowing,
and hence no foundation for research on Rust to build upon.
In this work, we set out to capture the essence of this model of ownership by
developing a type systems account of Rust's borrow checker. We present Oxide, a
formalized programming language close to source-level Rust (but with
fully-annotated types). This presentation takes a new view of lifetimes as an
approximation of the provenances of references, and our type system is able to
automatically compute this information through a substructural typing judgment.
We provide the first syntactic proof of type safety for borrow checking using
progress and preservation. Oxide is a simpler formulation of borrow checking -
including recent features such as non-lexical lifetimes - that we hope
researchers will be able to use as the basis for work on Rust.
Chinese: Rust声称通过在低级系统编程和高级应用编程之间架起桥梁，推动了工业级编程的发展。其论点的核心在于，这种能力使程序员能够构建更加可靠和高效的软件。实现这一目标的关键是借用检查器 - 一种新型的所有权方法，旨在平衡类型系统表达性和易用性。然而，到目前为止，没有核心类型系统能够捕获Rust的所有权和借用的概念，因此也没有研究Rust的基础。
在这项工作中，我们致力于通过开发Rust的借用检查器的类型系统描述，来捕捉这种所有权模型的本质。我们提出了Oxide，一种接近源代码级别的Rust的正式编程语言（但带有完全注释的类型）。这一展示从新的视角看待生命周期作为引用来源的近似值，我们的类型系统能够通过子结构类型判断自动计算此信息。我们提供了使用进步和保持的首次语法证明，用于检查类型安全性。Oxide是借用检查的简化形式，包括最近的功能，如非词法生命周期，我们希望研究人员能够将其作为研究Rust的基础。
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English: We present a method for inferring dense depth maps from images and sparse
depth measurements by leveraging synthetic data to learn the association of
sparse point clouds with dense natural shapes, and using the image as evidence
to validate the predicted depth map. Our learned prior for natural shapes uses
only sparse depth as input, not images, so the method is not affected by the
covariate shift when attempting to transfer learned models from synthetic data
to real ones. This allows us to use abundant synthetic data with ground truth
to learn the most difficult component of the reconstruction process, which is
topology estimation, and use the image to refine the prediction based on
photometric evidence. Our approach uses fewer parameters than previous methods,
yet, achieves the state of the art on both indoor and outdoor benchmark
datasets. Code available at:
https://github.com/alexklwong/learning-topology-synthetic-data.
Chinese: 我们提出了一种从图像和稀疏深度测量中推断密集深度图的方法。该方法通过利用合成数据来学习稀疏点云与密集自然形状之间的关联，并使用图像作为证据来验证预测的深度图。我们学习到的自然形状先验仅使用稀疏深度作为输入，而不是图像，因此该方法在尝试将学习到的模型从合成数据转移到真实数据时不受协变量偏移的影响。这使得我们能够使用大量的带有真实标签的合成数据来学习重建过程中最困难的组件，即拓扑估计，并使用图像根据光度学证据来细化预测。我们的方法使用的参数比以前的方法少，但在室内和室外基准数据集上都达到了最先进水平。代码可在以下网址找到：
https://github.com/alexklwong/learning-topology-synthetic-data.
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English: The integration of quantum emitters within topological nano-photonic devices
opens up new avenues for the control of light-matter interactions at the single
photon level. Here, we realise a spin-dependent, chiral light-matter interface
using individual semiconductor quantum dots embedded in a topological add-drop
filter. The filter is imprinted within a valley-Hall photonic crystal (PhC)
membrane and comprises a resonator evanescently coupled to a pair of access
waveguides. We show that the longitudinal modes of the resonator enable the
filter to perform wavelength-selective routing of light, protected by the
underlying topology. Furthermore, we demonstrate that for a quantum dot located
at a chiral point in the resonator, selective coupling occurs between
well-defined spin states and specific output ports of the topological device.
This behaviour is fundamental to the operation of chiral devices such as a
quantum optical circulator. Our device therefore represents a
topologically-protected building block with potential to play an enabling role
in the development of chiral integrated quantum photonic circuits.
Chinese: 在拓扑纳米光子器件中集成量子发射器，为控制单光子级别的光-物质相互作用开辟了新的途径。这里，我们实现了一个自旋依赖的、手性的光-物质界面，使用单个半导体量子点嵌入到拓扑加-减滤波器中。滤波器印制在谷-霍尔光子晶体（PhC）膜中，该膜包含一个谐振器，该谐振器与一对接入波导以虚耦合方式连接。我们表明谐振器的纵向模式使得滤波器能够执行波长选择性的光路由，受到底层拓扑的保护。此外，我们证明对于位于谐振器中手性点的量子点，在谐振器中手性点之间发生选择性耦合，以及与拓扑器件的特定输出端口。这种行为对于手性器件（如量子光学环）的操作是基本的。因此，我们的设备代表了一个拓扑保护的构建模块，有可能在手性集成量子光子电路的发展中发挥促进作用。
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English: Motivated by recent Parker Solar Probe (PSP) observations of "switchbacks"
(abrupt, large-amplitude reversals in the radial magnetic field, which exhibit
Alfv\'enic correlations) we examine the dynamics of large-amplitude Alfv\'en
waves in the expanding solar wind. We develop an analytic model which makes
several predictions: switchbacks should preferentially occur in regions where
the solar wind plasma has undergone a greater expansion, the switchback
fraction at radii comparable to PSP should be an increasing function of radius,
and switchbacks should have their gradients preferentially perpendicular to the
mean magnetic field direction. The expansion of the plasma generates small
compressive components as part of the wave's nonlinear evolution: these are
maximized when the normalized fluctuation amplitude is comparable to
$\sin\theta$, where $\theta$ is the angle between the propagation direction and
the mean magnetic field. These compressive components steepen the primary
Alfv\'enic waveform, keeping the solution in a state of nearly constant
magnetic field strength as its normalized amplitude $\delta B/B$ grows due to
expansion. The small fluctuations in the magnetic-field-strength are minimized
at a particular $\theta$-dependent value of $\beta$, usually of order unity,
and the density and magnetic-field-strength fluctuations can be correlated or
anticorrelated depending on $\beta$ and $\theta$. Example solutions of our
dynamical equation are presented; some do indeed form magnetic-field reversals.
Our predictions appear to match some previously unexplained phenomena in
observations and numerical simulations, providing evidence that the observed
switchbacks result from the nonlinear evolution of the initially
small-amplitude Alfv\'en waves already known to be present at the coronal base.
Chinese: 受最近帕克太阳探测器（PSP）对“回转”现象（径向磁场中突然发生的、幅度很大的反转，并表现出阿尔芬相关性）的观测所驱动，我们研究了膨胀日冕风中大振幅阿尔芬波的动力学。我们建立了一个解析模型，该模型做出了若干预测：回转现象应优先发生在日冕风等离子体经历了更大膨胀的区域；在与PSP半径相当的尺度上，回转的比例应随半径的增加而增加；回转的梯度应优先垂直于平均磁场方向。等离子体的膨胀作为波的非线性演化的一部分，产生了小的压缩分量：当归一化扰动幅度与$\sin\theta$相当时（其中$\theta$是传播方向与平均磁场之间的夹角），这些压缩分量达到最大值。这些压缩分量使主要的阿尔芬波形变陡峭，使解保持在磁场强度近似恒定的状态下，同时其归一化幅度$\delta B/B$由于膨胀而增加。磁场强度的微小波动在特定的、依赖于$\theta$的$\beta$值处最小化，通常为1的数量级，而密度和磁场强度波动之间的相关性或反相关性取决于$\beta$和$\theta$。我们展示了我们动力学方程的一些示例解；其中一些确实形成了磁场反转。我们的预测似乎与观测和数值模拟中一些先前无法解释的现象相吻合，为观测到的回转现象是由最初存在于日冕底部的、已知的小振幅阿尔芬波的线性演化所导致的这一观点提供了证据。
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English: Several variants of the cops and robbers (CR) game have been studied in the
past. In this paper we examine a novel variant, which is played between two
cops, each one independently trying to catch a "passive robber". We will call
this the Selfish Cops and Passive Robber {SCPR} game. In short, SCPR is a
stochastic two-player, zero-sum game where the opponents are the two cop
players. We study sequential and concurrent versions of the SCPR game. For both
cases we prove the existence of value and optimal strategies and present
algorithms for the computation of these.
Chinese: 过去已经研究过警匪游戏（CR）的几种变体。在本文中，我们考察了一种新型变体，该变体由两名警员进行游戏，每人各自独立地追捕一个"被动匪徒"。我们将这种游戏称为自私警与被动匪徒游戏 {SCPR}。简而言之，SCPR是一种随机二人零和博弈，其中对手是两名警员玩家。我们研究了SCPR游戏的顺序和并发版本。对于这两种情况，我们证明了价值函数和最优策略的存在性，并给出了计算这些的算法。
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English: The widespread adoption of autonomous systems such as drones and assistant
robots has created a need for real-time high-quality semantic scene
segmentation. In this paper, we propose an efficient yet robust technique for
on-the-fly dense reconstruction and semantic segmentation of 3D indoor scenes.
To guarantee (near) real-time performance, our method is built atop an
efficient super-voxel clustering method and a conditional random field with
higher-order constraints from structural and object cues, enabling progressive
dense semantic segmentation without any precomputation. We extensively evaluate
our method on different indoor scenes including kitchens, offices, and bedrooms
in the SceneNN and ScanNet datasets and show that our technique consistently
produces state-of-the-art segmentation results in both qualitative and
quantitative experiments.
Chinese: 无人机和辅助机器人等自主系统的广泛应用，产生了对实时高质量语义场景分割的需求。在本文中，我们提出了一种高效且鲁棒的动态密集重建和3D室内场景语义分割技术。为了保证（近）实时性能，我们的方法建立在高效的超级体素聚类方法和条件随机场之上，该随机场从结构和物体线索中获取高阶约束，从而实现无需任何预计算的渐进式密集语义分割。我们在SceneNN和ScanNet数据集上的不同室内场景（包括厨房、办公室和卧室）上广泛评估了我们的方法，并显示我们的技术在定性和定量实验中均持续产生最先进的分割结果。
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English: We solve the time-dependent Schrodinger equation for the combination of a
spin system interacting with a spin bath environment. In particular, we focus
on the time development of the reduced density matrix of the spin system. Under
normal circumstances we show that the environment drives the reduced density
matrix to a fully decoherent state, and furthermore the diagonal elements of
the reduced density matrix approach those expected for the system in the
canonical ensemble. We show one exception to the normal case is if the spin
system cannot exchange energy with the spin bath. Our demonstration does not
rely on time-averaging of observables nor does it assume that the coupling
between system and bath is weak. Our findings show that the canonical ensemble
is a state that may result from pure quantum dynamics, suggesting that quantum
mechanics may be regarded as the foundation of quantum statistical mechanics.
Chinese: 我们解决了一个自旋系统与自旋环境相互作用的时变薛定谔方程。特别是，我们关注自旋系统的减少密度矩阵随时间的发展。通常情况下，我们证明环境驱动减少密度矩阵达到一个完全去相干的状态，并且进一步证明减少密度矩阵的对角元素接近系统在典型集合中预期的状态。我们指出，正常情况下的一个例外是，如果自旋系统无法与自旋环境交换能量。我们的演示不依赖于观测量的时间平均，也不假设系统与环境之间的耦合是微弱的。我们的发现表明，典型集合可能是一个由纯粹量子动力学产生的状态，这表明量子力学可能是量子统计力学的基础。
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English: A solid-on-solid growth model for dimer adsorption and desorption is
introduced and studied numerically. The special property of the model is that
dimers can only desorb at the edges of terraces. It is shown that the model
exhibits a roughening transition from a smooth to a rough phase. In both phases
the interface remains pinned to the bottom layer and does not propagate. Close
to the transition certain critical properties are related to those of a
unidirectionally coupled hierarchy of parity-conserving branching-annihilating
random walks.
Chinese: 一种用于二聚体吸附和脱附的固体-固体生长模型被引入并进行了数值研究。该模型的特殊性质是二聚体只能在台地的边缘脱附。研究表明，该模型表现出从光滑相到粗糙相的粗糙化转变。在两个相中，界面都保持在底层并不会有传播。在转变附近，某些临界性质与单向耦合的守恒偶数分支-湮灭随机游走层次结构的性质相关。
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English: We have considered a model \cite{ma-weg}, where masses and a mixing pattern
for neutrinos are governed by six Higgs triplets and $A_4$ symmetry. In this
model we have applied a certain diagonalisation procedure through which we have
shown that neutrino masses can have both normal or inverted hierarchy. We have
also shown that current neutrino oscillation data can be explained in this
model.
Chinese: 我们考虑了一个模型 \cite{ma-weg}，其中中微子的质量及混合模式由六个Higgs三重态和$A_4$对称性控制。在这个模型中，我们应用了一种特定的对角化程序，通过它我们展示了中微子质量可以具有正常或倒序的层次结构。我们也展示了当前的中微子振荡数据可以在这个模型中得到解释。
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English: In island biogeography, it is widely accepted that species richness on island
depends on the area and isolation of the island as well as the species pool on
the mainland. Delavaux et al. (2024) suggest that species richness on oceanic
islands also depends on the proportion of mutualists on the mainland, based on
the idea that mutualists require specific interaction partners for their
survival and thus have lower chances of establishment after successful
immigration. As the proportion of mutualists increases towards the tropics,
this effect could explain a weaker latitudinal diversity gradient (LDG) for
oceanic islands. However, after re-analyzing their data, we have doubts if
these conclusions are supported by the available data.
Chinese: 在岛屿生物地理学中，人们普遍认为岛屿物种丰富度取决于岛屿的面积和隔离程度，以及大陆上的物种库。Delavaux等人（2024年）提出，海洋岛屿的物种丰富度也取决于大陆上互利共生者的比例，基于这样一个观点：互利共生者需要特定的互动伙伴来生存，因此在成功移民后建立种群的机会较低。随着互利共生者比例向热带地区的增加，这一效应可能解释了海洋岛屿纬度多样性梯度（LDG）的减弱。然而，在重新分析他们的数据后，我们对其结论是否得到现有数据的支持表示怀疑。
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English: Rapid, hyper-Eddington accretion is likely to power the central engines of
gamma-ray bursts (GRBs). In the extreme conditions of densities and
temperatures the accreting torus is cooled by neutrino emission rather than by
radiation. Another important cooling mechanism is the advection of energy into
the central black hole. We compute the time evolution of a neutrino-dominated
disc that proceeds during the burst and investigate the changes in its density
and temperature. The discrimination between short and long bursts is made on
the basis of the different rates of material inflow to the outer parts of the
disc, thus favoring the binary merger scenario for the short GRBs and the
collapsar scenario for the long ones. Within the context of the collapsar
model, we also study the evolution of the photon luminosity of the remnant disc
up to times of the order of 1 day, and discuss its implications for the
production of emission lines in GRB spectra.
Chinese: 快速、超爱丁顿吸积可能为伽马射线暴（GRBs）的中心引擎提供能量。在极端的密度和温度条件下，吸积的环状物通过中微子辐射而非辐射冷却。另一个重要的冷却机制是将能量输运到中心黑洞。我们计算了在爆发过程中进行的以中微子为主导的盘的时间演化，并研究了其密度和温度的变化。短暴和长暴之间的区分是基于物质流入盘外部的不同速率，因此有利于短GRBs的双星合并情景，以及长GRBs的塌缩星情景。在塌缩星模型框架内，我们还研究了残留盘的光子亮度演化，直至约1天的时间尺度，并讨论了其对GRB光谱中发射线产生的意义。
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English: This work studies the systematic reduced transition probabilities B(E2),
intrinsic quadrupole moments and deformation parameters of Pd isotopes with
even neutrons from N= 62 to 66. The downward reduced transition probabilities
B(E2) from gamma transition 8+ to 6+, 6+ to 4+, 4+ to 2+ and 2+ to 0+ states of
even-even 108-112Pd isotopes were calculated by the Interacting Boson Model
(IBM-1) and compared with the available previous experimental results. The
ratio of the excitation energies of the first 4+ and the first 2+ excited
states, R4/2, is also studied for the classification of symmetry of these
nuclei. Furthermore we have studied systematically the transition rate R of
some of the low-lying quadrupole collective states in comparison with the
available experimental data. The associated quadrupole moments and deformation
parameters have been calculated. The results of this calculation are in good
agreement with the corresponding available experimental data. The 108-112Pd
isotopes show the O(6) symmetry.
Chinese: 这项工作研究了从N=62到66的钯同位素（偶数中子）的系统降低的B(E2)跃迁概率、固有四极矩和形变参数。通过相互作用玻色子模型（IBM-1）计算了偶偶核108-112Pd同位素从γ跃迁8+到6+、6+到4+、4+到2+和2+到0+状态的向下降低的B(E2)跃迁概率，并将这些结果与可用的先前实验数据进行了比较。还研究了第一4+和第一2+激发态激发能的比值R4/2，以对这些核的对称性进行分类。此外，我们还系统地研究了与可用的实验数据相比的一些低能四极集体状态的跃迁率R。已经计算了相关的四极矩和形变参数。这些计算结果与相应的可用的实验数据吻合良好。108-112Pd同位素显示出O(6)对称性。
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English: This work is devoted to study the existence of infinitely many weak solutions
to nonlocal equations involving a general integrodifferential operator of
fractional type. These equations have a variational structure and we find a
sequence of nontrivial weak solutions for them exploiting the
${\mathbb{Z}}_2$-symmetric version of the Mountain Pass Theorem. To make the
nonlinear methods work, some careful analysis of the fractional spaces involved
is necessary. As a particular case, we derive an existence theorem for the
fractional Laplacian, finding nontrivial solutions of the equation $$
\left\{\begin{array}{ll} (-\Delta)^s u=f(x,u) & {\mbox{in}} \Omega\\ u=0 &
{\mbox{in}} \erre^n\setminus \Omega. \end{array} \right. $$ As far as we know,
all these results are new and represent a fractional version of classical
theorems obtained working with Laplacian equations.
Chinese: 这项工作致力于研究涉及一类分数阶泛函微分算子的非局部方程无限多个弱解的存在性。这些方程具有变分结构，我们利用山丘定理的${\mathbb{Z}}_2$对称版本找到了一系列非平凡弱解。为了使非线性方法有效，需要对涉及的分数空间进行一些仔细的分析。作为特例，我们推导出分数拉普拉斯算子的存在定理，找到了方程
$$
\left\{
\begin{array}{ll}
(-\Delta)^s u=f(x,u) & {\mbox{在}} \Omega\\
u=0 & {\mbox{在}} \erre^n\setminus \Omega.
\end{array}
\right.
$$
的非平凡解。据我们所知，所有这些结果都是新的，并且代表了与拉普拉斯方程一起获得经典定理的分数版本。
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English: In this work, I present an optimization problem which consists of assigning
entries of a stellar catalog to multiple entries of another stellar catalog
such that the probability of such assignment is maximum. I show a way of
modeling it as a Maximum Weighted Stable Set Problem which is further used to
solve a real astronomical instance and I partially characterize the forbidden
subgraphs of the resulting family of graphs given by that reduction. Finally, I
prove that the problem is NP-Hard.
Chinese: 在这项工作中，我提出一个优化问题，它涉及将一个恒星目录中的条目分配到另一个恒星目录中的多个条目上，使得这种分配的概率最大化。我展示了一种将其建模为最大加权稳定集问题的方法，该问题进一步用于解决一个实际的天文实例，并且我对由该归约产生的图形结果家族中的禁止子图进行了部分表征。最后，我证明了该问题为NP难问题。
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English: We provide a general theoretical platform based on quantized radiation in
absorptive and inhomogeneous media for investigating the coherent interaction
of light with metallic structures in the immediate vicinity of quantum
emitters. In the case of a very small metallic cluster, we demonstrate extreme
regimes where a single emitter can either counteract or enhance particle
absorption by three orders of magnitude. For larger structures, we show that an
emitter can eliminate both scattering and absorption and cloak a plasmonic
antenna. We provide physical interpretations of our results and discuss their
applications in active metamaterials and quantum plasmonics.
Chinese: 我们基于吸收介质和不均匀介质中的量子辐射，提供了一个研究光与金属结构在量子发射体附近即时区域内相干相互作用的通用理论平台。在一个非常小的金属团簇的情况下，我们展示了极端情形，其中单个发射体可以要么抵消，要么增强粒子吸收高达三个数量级。对于更大的结构，我们展示了发射体可以消除散射和吸收，并且掩蔽一个等离子体天线。我们提供了对结果的物理解释，并讨论了它们在主动超材料和量子等离子体中的应用。
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English: A potential model description of heavy quarkonium can be rigorously deduced
from QCD under some circumstances. The potentials can be unambiguously related
with Wilson loops with gluonic insertions, the spectral decomposition of which
is a function of the spectrum and matrix elements solution of the static limit
of NRQCD. This spectrum is nothing but the static singlet potential and the
hybrid potentials (which correspond to the gluonic excitations). We will
quantitatively show that the latter unambiguously relate to the gluelumps at
short distances using effective field theories.
Chinese: 在某些情况下，一种潜在的模型描述可以从量子色动力学中得到严格推导。这些势可以明确地与带胶子插入的威尔逊回路相关联，其谱分解是静态极限下非相对论量子色动力学的谱和矩阵元解的函数。这个谱无非就是静态单态势和混合势（对应于胶子激发）。我们将使用有效场论，定量地证明后者明确地与短距离处的胶子团相关联。
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English: The Cepheid Period-Luminosity relation is unquestionably one of the most
powerful tools at our disposal for determining the extragalactic distance
scale. While significant progress has been made in the past few years towards
its understanding and characterisation, both on the observational (e.g. the HST
Key Project) and theoretical (e.g. non-linear pulsation models, non-LTE
atmospheres etc.) sides, the debate on the influence that chemical composition
may have on the Period-Luminosity relation is still unsettled. Current
estimates lead to differences in the distance as large as 15%, effectively
limiting the accuracy of Cepheids as distance indicators.
To further tackle this problem, we have obtained high resolution spectra of a
large sample of Cepheids in our Galaxy and the Magellanic Clouds. The superb
quality of the data allow us to probe the detailed effects of chemical
composition (alpha, iron-group, and heavy elements) over more than a factor of
ten in metallicity. Here, we present the first preliminary results of the
analysis of iron abundances in a sub-sample of Cepheids.
Chinese: 仙后座周期-亮度关系无疑是我们在确定类星体距离尺度方面最强大的工具之一。尽管在过去几年里，在观测（例如哈勃太空望远镜的关键项目）和理论（例如非线性脉动模型、非局部热平衡大气等）方面都取得了显著的进展，但关于化学成分可能对周期-亮度关系产生的影响的争论仍未解决。目前的估计导致距离差异高达15%，实际上限制了仙后座作为距离指标的准确性。为了进一步解决这个问题，我们已经获得了我们银河系和麦哲伦星云中大量仙后座的高分辨率光谱。数据的高质量使我们能够探测化学成分（α元素、铁族元素和重元素）在超过十个金属丰度因子上的详细影响。在这里，我们展示了仙后座亚样本中铁丰度分析的第一批初步结果。
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English: For nonautonomous linear difference equations in Banach spaces we show that a
very general type of dichotomic behavior persists under small enough additive
linear perturbations. By using a new approach, we obtain two general robustness
theorems that improve several results in the literature and also contain new
situations. In particular, unlike several existent results for particular
growth rates, we show that, up to a multiplicative constant, the dichotomic
behavior for the perturbed equation is the same as the one for the original
equation.
Chinese: 对于非自治线性差分方程在Banach空间中，我们表明在足够小的加性线性扰动下，一种非常一般的二分行为依然存在。通过使用一种新方法，我们得到了两个改进了文献中若干结果并且也包含了新情况的通用鲁棒性定理。特别是，与若干特定增长率存在的结果不同，我们展示了，在乘法常数内，扰动方程的二分行为与原方程的相同。
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English: In compressed sensing, the sensing matrix is assumed perfectly known.
However, there exists perturbation in the sensing matrix in reality due to
sensor offsets or noise disturbance. Directions-of-arrival (DoA) estimation
with off-grid effect satisfies this situation, and can be formulated into a
(non)convex optimization problem with linear inequalities constraints, which
can be solved by the interior point method (using the CVX tools), but at a
large computational cost. In this work, in order to design efficient
algorithms, we consider various alternative formulations, such as unconstrained
formulation, primal-dual formulation, or conic formulation to develop
group-sparsity promoted solvers. First, the consensus alternating direction
method of multipliers (C-ADMM) is applied. Then, iterative algorithms for the
BPDN formulation is proposed by combining the Nesterov smoothing technique with
accelerated proximal gradient method, and the convergence analysis of the
method is conducted as well.
We also developed a variant of EGT (Excessive Gap Technique)-based
primal-dual method to systematically reduce the smoothing parameter
sequentially. Finally, we propose algorithms for quadratically constrained
L2-L1 mixed norm minimization problem by using the smoothed dual conic
optimization (SDCO) and continuation technique. The performance of accuracy and
convergence for all the proposed methods are demonstrated in the numerical
simulations.
Chinese: 在压缩感知中，假设感知矩阵是完美已知的。然而，由于传感器偏移或噪声干扰，在现实中感知矩阵存在扰动。具有离网效应的到达方向（DoA）估计满足这种情况，并且可以表述为一个（非）凸优化问题，带有线性不等式约束，可以使用内点法（使用CVX工具）解决，但计算成本很大。在这项工作中，为了设计高效的算法，我们考虑了各种替代方案，例如无约束方案、原对偶方案或锥形方案，以开发组稀疏性促进的求解器。首先，应用了共识交替方向乘子法（C-ADMM）。然后，通过结合Nesterov平滑技术和加速近端梯度方法，提出了BPDN公式的迭代算法，并进行了该方法收敛性的分析。
我们还开发了一种基于EGT（过隙技术）的原对偶方法的变体，以系统地顺序减少平滑参数。最后，我们通过使用平滑对偶锥优化（SDCO）和连续技术，提出了二次约束L2-L1混合范数最小化问题的算法。所有提出的方法的精度和收敛性在数值模拟中得到验证。
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English: An identifying code in a graph $G$ is a dominating set $C$ such that the
closed neighborhood of each vertex in $G$ has a distinct intersection with $C$.
In 2008, Gravier et al. determined the minimum cardinality of an identifying
code of the Cartesian product of two cliques with the same size. In this note,
we generalize this result to the Cartesian product of any two nontrivial
cliques.
Chinese: 在图 $G$ 中的一个识别码是一个支配集 $C$，使得 $G$ 中每个顶点的闭邻域都与 $C$ 有唯一的交集。在2008年，Gravier等人确定了具有相同大小的两个完全子图的笛卡尔积的识别码的最小基数。在这篇笔记中，我们将这个结果推广到任意两个非平凡完全子图的笛卡尔积。
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English: The quantum spin Hall insulator bismuthene, a two-third monolayer of bismuth
on SiC(0001), is distinguished by helical metallic edge states that are
protected by a groundbreaking 800 meV topological gap, making it ideal for room
temperature applications. This massive gap inversion arises from a unique
synergy between flat honeycomb structure, strong spin orbit coupling, and an
orbital filtering effect that is mediated by the substrate. However, the rapid
oxidation of bismuthene in air has severely hindered the development of
applications, so far confining experiments to ultra-high vacuum conditions.
Here, we successfully overcome this barrier, intercalating bismuthene between
SiC and a protective sheet of graphene. As we demonstrate through scanning
tunneling microscopy and photoemission spectroscopy, graphene intercalation
preserves the structural and topological integrity of bismuthene, while
effectively shielding it from oxidation in air. We identify hydrogen as the
critical component that was missing in previous bismuth intercalation attempts.
Our findings facilitate ex-situ experiments and pave the way for the
development of bismuthene based devices, signaling a significant step forward
in the development of next-generation technologies.
Chinese: 量子自旋霍尔绝缘体双三层的铋烯，即在SiC(0001)上的二分之一单层铋，因其具有受保护的螺旋金属边缘态而著称，这些边缘态由突破性的800 meV拓扑间隙所保护，使其非常适合室温应用。这一巨大的能隙反转来自于一个独特的协同效应，即扁平蜂窝结构、强大的自旋轨道耦合以及由基底介导的轨道过滤效应。然而，铋烯在空气中的快速氧化严重阻碍了其应用的发展，迄今为止，实验仅限于超高真空条件。在这里，我们成功地克服了这一障碍，将铋烯夹在SiC和一层保护性的石墨烯之间。正如我们通过扫描隧道显微镜和光电子能谱学所展示的那样，石墨烯的插入保持了铋烯的结构和拓扑完整性，同时有效地保护其免受空气氧化。我们确定氢是先前尝试中将铋插入石墨烯时缺失的关键成分。我们的发现促进了离体实验，并为开发基于铋烯的器件铺平了道路，标志着向下一代技术发展的重大一步。
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English: The nature of charge transport within a correlated background medium can be
described by spinless fermions coupled to bosons in the model introduced by
Edwards. Combining numerical density matrix renormalization group and
analytical projector-based renormalization methods we explore the ground-state
phase diagram of the Edwards model in one dimension. Below a critical boson
frequency any long-range order disappears and the system becomes metallic. If
the charge carriers are coupled to slow quantum bosons the Tomonaga-Luttinger
liquid is attractive and finally makes room for a phase separated state, just
as in the t-J model. The phase boundary separating repulsive from the
attractive Tomonaga-Luttinger liquid is determined from long-wavelength charge
correlations, whereas fermion segregation is indicated by a vanishing inverse
compressibility. On approaching phase separation the photoemission spectra
develop strong anomalies.
Chinese: 在关联背景介质中电荷传输的性质可以通过爱德华斯提出的模型中无自旋费米子与玻色子耦合来描述。结合数值密度矩阵重整化群和基于分析投影的重整化方法，我们探索了一维爱德华斯模型的基态相图。在临界玻色子频率以下，任何长程序都会消失，系统变为金属态。如果电荷载体与慢速量子玻色子耦合，汤姆孙-卢瑟福液体是吸引的，最终为相分离态腾出空间，就像t-J模型一样。将排斥的汤姆孙-卢瑟福液体与吸引的汤姆孙-卢瑟福液体分开的相边界由长波长电荷相关性确定，而费米子分离则由消失的逆压缩性指示。在接近相分离时，光电子能谱出现强烈异常。
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English: We consider the problem of the implementation of Stimulated Raman Adiabatic
Passage (STIRAP) processes in degenerate systems, with a view to be able to
steer the system wave function from an arbitrary initial superposition to an
arbitrary target superposition. We examine the case a $N$-level atomic system
consisting of $ N-1$ ground states coupled to a common excited state by laser
pulses. We analyze the general case of initial and final superpositions
belonging to the same manifold of states, and we cover also the case in which
they are non-orthogonal. We demonstrate that, for a given initial and target
superposition, it is always possible to choose the laser pulses so that in a
transformed basis the system is reduced to an effective three-level $\Lambda$
system, and standard STIRAP processes can be implemented. Our treatment leads
to a simple strategy, with minimal computational complexity, which allows us to
determine the laser pulses shape required for the wanted adiabatic steering.
Chinese: 我们考虑在简并系统中实现受激拉曼绝热 passage (STIRAP) 过程的问题，目的是能够将系统波函数从任意初始叠加态引导至任意目标叠加态。我们考察一个由 $N$ 能级原子系统构成的案例，该系统包含 $N-1$ 个基态，这些基态通过激光脉冲与一个共同激发态耦合。我们分析了初始和最终叠加态属于同一状态流形的一般情况，也涵盖了它们非正交的情况。我们证明，对于给定的初始和目标叠加态，总能选择激光脉冲，使得在变换后的基底下系统被简化为有效三能级 Λ 系统，从而可以实施标准 STIRAP 过程。我们的研究得出了一种计算复杂度最小的简单策略，使我们能够确定实现所需绝热引导所需的激光脉冲形状。
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English: Pooling and unpooling are two essential operations in constructing
hierarchical spherical convolutional neural networks (HS-CNNs) for
comprehensive feature learning in the spherical domain. Most existing models
employ downsampling-based pooling, which will inevitably incur information loss
and cannot adapt to different spherical signals and tasks. Besides, the
preserved information after pooling cannot be well restored by the subsequent
unpooling to characterize the desirable features for a task. In this paper, we
propose a novel framework of HS-CNNs with a lifting structure to learn adaptive
spherical wavelets for pooling and unpooling, dubbed LiftHS-CNN, which ensures
a more efficient hierarchical feature learning for both image- and pixel-level
tasks. Specifically, adaptive spherical wavelets are learned with a lifting
structure that consists of trainable lifting operators (i.e., update and
predict operators). With this learnable lifting structure, we can adaptively
partition a signal into two sub-bands containing low- and high-frequency
components, respectively, and thus generate a better down-scaled representation
for pooling by preserving more information in the low-frequency sub-band. The
update and predict operators are parameterized with graph-based attention to
jointly consider the signal's characteristics and the underlying geometries. We
further show that particular properties are promised by the learned wavelets,
ensuring the spatial-frequency localization for better exploiting the signal's
correlation in both spatial and frequency domains. We then propose an unpooling
operation that is invertible to the lifting-based pooling, where an inverse
wavelet transform is performed by using the learned lifting operators to
restore an up-scaled representation. Extensive empirical evaluations on various
spherical domain tasks validate the superiority of the proposed LiftHS-CNN.
Chinese: 池化和反池化是构建用于球面域综合特征学习的分层球面卷积神经网络（HS-CNNs）的两个基本操作。大多数现有模型采用基于下采样的池化，这不可避免地会导致信息损失，并且无法适应不同的球面信号和任务。此外，池化后保留的信息不能通过后续的反池化很好地恢复，以表征特定任务所需的特征。在本文中，我们提出了一种具有提升结构的HS-CNNs新框架，用于学习自适应球面小波进行池化和反池化，称为LiftHS-CNN，它确保了图像级和像素级任务都进行更有效的分层特征学习。具体来说，通过一个由可训练的提升算子（即更新和预测算子）组成的提升结构学习自适应球面小波。有了这个可学习的提升结构，我们可以自适应地将信号分为包含低频和高频分量的两个子带，从而通过在低频子带中保留更多信息来生成更好的下采样表示。更新和预测算子通过基于图的关注参数化，共同考虑信号的特征和底层几何。我们进一步表明，通过学习的小波具有特定的性质，确保了空间频率定位，从而更好地利用信号在空间和频率域中的相关性。然后，我们提出了一种反池化操作，它是基于提升的池化的可逆操作，通过使用学习到的提升算子执行逆小波变换来恢复上采样表示。在球面域的各种任务上的大量实证评估验证了所提出的LiftHS-CNN的优越性。
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English: Two different methods have been employed to determine the plasma temperature
in a laser-cluster fusion experiment on the Texas Petawatt laser. In the first,
the temperature was derived from time-of-flight data of deuterium ions ejected
from exploding D2 or CD4 clusters. In the second, the temperature was measured
from the ratio of the rates of two different nuclear fusion reactions occurring
in the plasma at the same time: D(d, 3He)n and 3He(d, p)4He. The temperatures
determined by these two methods agree well, which indicates that: i) The ion
energy distribution is not significantly distorted when ions travel in the
disassembling plasma; ii) The kinetic energy of deuterium ions, especially the
hottest part responsible for nuclear fusion, is well described by a
near-Maxwellian distribution.
Chinese: 在德克萨斯佩塔瓦特激光器上的激光-聚变实验中，采用了两种不同的方法来确定等离子体温度。第一种方法是通过从爆炸的D2或CD4簇中喷射出的氘离子飞行时间数据推导出温度。第二种方法是通过测量同时发生在等离子体中的两种不同核聚变反应速率之比来测量温度：D(d, 3He)n和3He(d, p)4He。这两种方法确定的温度吻合得很好，这表明：i) 当离子在分解的等离子体中移动时，离子能量分布没有显著扭曲；ii) 氘离子的动能，尤其是负责核聚变的最热部分，很好地被近麦克斯韦分布所描述。
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English: We present the temperature and polarization angular power spectra of the CMB
measured by the Atacama Cosmology Telescope (ACT) from 5400 deg$^2$ of the
2013-2016 survey, which covers $>$15000 deg$^2$ at 98 and 150 GHz. For this
analysis we adopt a blinding strategy to help avoid confirmation bias and,
related to this, show numerous checks for systematic error done before
unblinding. Using the likelihood for the cosmological analysis we constrain
secondary sources of anisotropy and foreground emission, and derive a
"CMB-only" spectrum that extends to $\ell=4000$. At large angular scales,
foreground emission at 150 GHz is $\sim$1% of TT and EE within our selected
regions and consistent with that found by Planck. Using the same likelihood, we
obtain the cosmological parameters for $\Lambda$CDM for the ACT data alone with
a prior on the optical depth of $\tau=0.065\pm0.015$. $\Lambda$CDM is a good
fit. The best-fit model has a reduced $\chi^2$ of 1.07 (PTE=0.07) with
$H_0=67.9\pm1.5$ km/s/Mpc. We show that the lensing BB signal is consistent
with $\Lambda$CDM and limit the celestial EB polarization angle to $\psi_P
=-0.07^{\circ}\pm0.09^{\circ}$. We directly cross correlate ACT with Planck and
observe generally good agreement but with some discrepancies in TE. All data on
which this analysis is based will be publicly released.
Chinese: 我们展示了由阿塔卡马宇宙望远镜（ACT）测量的宇宙微波背景（CMB）的温度和偏振角功率谱，这些数据来自2013-2016年调查的5400平方度区域，该调查覆盖了大于15000平方度的98和150 GHz频段。为了进行这项分析，我们采用了盲化策略以帮助避免确认偏差，并且在此相关方面，在解盲之前展示了大量的系统误差检查。使用宇宙学分析的似然函数，我们限制了各向异性次级源和前景辐射，并推导出一个仅包含"CMB"的谱，该谱延伸到$\ell=4000$。在大的角尺度上，150 GHz的前景辐射在我们选定的区域内约为TT和EE的1%，与普朗克卫星的结果一致。使用相同的似然函数，我们仅对ACT数据获得了$\Lambda$CDM的宇宙学参数，其先验的光学深度为$\tau=0.065\pm0.015$。$\Lambda$CDM是一个良好的拟合。最佳拟合模型具有减小的$\chi^2$值为1.07（PTE=0.07），$H_0=67.9\pm1.5$ km/s/Mpc。我们表明，透镜效应BB信号与$\Lambda$CDM一致，并将天体EB偏振角限制在$\psi_P=-0.07^{\circ}\pm0.09^{\circ}$。我们直接将ACT与普朗克进行交叉相关性分析，观察到总体上良好的一致性，但在TE方面存在一些差异。所有基于此分析的数据都将公开发布。
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English: In magnetoresistive (MR) studies of magnetic multilayers composed of
combinations of ferromagnetic (F) and non-magnetic (N) metals, the magnetic
moment (or related 'spin') of each conduction electron plays a crucial role,
supplementary to that of its charge. While initial analyses of MR in such
multilayers assumed that the direction of the spin of each electron stayed
fixed as the electron transited the multilayer, we now know that this is true
only in a certain limit. Generally, the spins 'flip' in a distance
characteristic of the metal, its purity, and the temperature. They can also
flip at F/N or N1/N2 interfaces. In this review we describe how to measure the
lengths over which electron moments flip in pure metals and alloys, and the
probability of spin-flipping at metallic interfaces. Spin-flipping within
metals is described by a spin-diffusion length,l^M(sf), where the metal M = F
or N. Spin-diffusion lengths are the characteristic lengths in the
current-perpendicular-to-plane (CPP) and lateral non-local (LNL) geometries
that we focus upon in this review. In certain simple cases, l^N(sf) sets the
distance over which the CPP-MR and LNL-MR decrease as the N-layer thickness
(CPP-MR) or N-film length (LNL) increases, and l^F(sf) does the same for
increase of the CPP-MR with increasing F-layer thickness. Spin-flipping at
M1/M2 interfaces can be described by a parameter, delta(M1/M2), which
determines the spin-flipping probability, P = 1 - exp(-delta). Increasing
delta(M1/M2) usually decreases the MR. We list measured values of these
parameters and discuss the limitations on their determinations.
Chinese: 在由铁磁体（F）和非磁性体（N）金属组合而成的磁性多层膜的研究中，每个导电电子的磁矩（或相关的“自旋”）起着至关重要的作用，补充了其电荷的作用。尽管对这类多层膜中磁阻（MR）的初始分析假设每个电子的自旋方向在电子穿过多层膜时保持固定，但我们现在知道这仅在特定条件下成立。通常，自旋会在一个与金属特性、纯度和温度相关的特征距离内“翻转”。它们也可以在F/N或N1/N2界面处翻转。在本综述中，我们描述了如何测量纯净金属和合金中电子矩翻转的长度，以及金属界面处自旋翻转的概率。金属内部的自旋翻转由自旋扩散长度l^M(sf)描述，其中金属M = F或N。自旋扩散长度是本综述中我们关注的电流垂直于平面（CPP）和非局域横向（LNL）几何形状中的特征长度。在某些简单情况下，l^N(sf)决定了随着N层厚度（CPP-MR）或N膜长度（LNL）的增加，CPP-MR和LNL-MR减少的距离，而l^F(sf)则对随F层厚度增加而增加的CPP-MR起相同作用。M1/M2界面处的自旋翻转可以用一个参数delta(M1/M2)来描述，该参数决定了自旋翻转概率P = 1 - exp(-delta)。增加delta(M1/M2)通常会导致MR降低。我们列出了这些参数的测量值，并讨论了其测定的局限性。
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English: Galactic binary neutron stars (BNSs) are a unique laboratory to probe the
evolution of BNSs and their progenitors. Here, we use a new version of the
population synthesis code SEVN to evolve the population of Galactic BNSs, by
modeling the spin up and down of pulsars self-consistently. We analyze the
merger rate $\mathcal{R}_{\rm MW}$, orbital period $P_{\rm orb}$, eccentricity
$e$, spin period $P$, and spin period derivative $\dot{P}$ of the BNS
population. Values of the common envelope parameter $\alpha=1 - 3$ and an
accurate model of the Milky Way star formation history best reproduce the BNS
merger rate in our Galaxy ($\mathcal{R}_{\rm MW}\approx{}30$ Myr$^{-1}$). We
apply radio-selection effects to our simulated BNSs and compare them to the
observed population. Using a Dirichlet process Gaussian mixture method, we
evaluate the four-dimensional likelihood in the $(P_{\rm orb}, e, P, \dot{P})$
space, by comparing our radio-selected simulated pulsars against Galactic BNSs.
Our analysis favours an uniform initial distribution for both the magnetic
field ($10^{10-13}$ G) and the spin period ($10-100$ ms). The implementation of
radio selection effects is critical to match not only the spin period and
period derivative, but also the orbital period and eccentricity of Galactic
BNSs. According to our fiducial model, the Square Kilometre Array will detect
$\sim 20$ new BNSs in the Milky Way.
Chinese: 银河系双中子星（BNSs）是研究双中子星及其前体的演化的独特实验室。在这里，我们使用SEVN代码的新版本，通过自洽地模拟脉冲星的加速和减速来演化银河系双中子星种群。我们分析了双中子星种群的合并率$\mathcal{R}_{\rm MW}$、轨道周期$P_{\rm orb}$、偏心率$e$、自转周期$P$和自转周期导数$\dot{P}$。公共包层参数$\alpha=1 - 3$和银河系恒星形成历史的精确模型最佳地再现了我们银河系中的双中子星合并率（$\mathcal{R}_{\rm MW}\approx{}30$ Myr$^{-1}$）。我们将射电选择效应应用于我们模拟的双中子星，并与观测种群进行比较。使用Dirichlet过程高斯混合方法，我们通过将我们的射电选择模拟脉冲星与银河系双中子星进行比较，在$(P_{\rm orb}, e, P, \dot{P})$空间中评估四维似然。我们的分析支持磁场（$10^{10-13}$ G）和自转周期（$10-100$ ms）的均匀初始分布。射电选择效应的实施对于匹配银河系双中子星的自转周期和周期导数，以及轨道周期和偏心率至关重要。根据我们的参考模型，平方公里阵列将在银河系中探测到约20个新的双中子星。
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English: The switch chain is a well-studied Markov chain which can be used to sample
approximately uniformly from the set $\Omega(\boldsymbol{d})$ of all graphs
with a given degree sequence $\boldsymbol{d}$. Polynomial mixing time (rapid
mixing) has been established for the switch chain under various conditions on
the degree sequences. Amanatidis and Kleer introduced the notion of strongly
stable families of degree sequences, and proved that the switch chain is
rapidly mixing for any degree sequence from a strongly stable family. Using a
different approach, Erd\H{o}s et al. recently extended this result to the
(possibly larger) class of P-stable degree sequences, introduced by Jerrum and
Sinclair in 1990. We define a new notion of stability for a given degree
sequence, namely $k$-\emph{stability}, and prove that if a degree sequence
$\boldsymbol{d}$ is 8-stable then the switch chain on $\Omega(\boldsymbol{d})$
is rapidly mixing. We also provide sufficient conditions for P-stability,
strong stability and 8-stability. Using these sufficient conditions, we give
the first proof of P-stability for various families of heavy-tailed degree
sequences, including power-law degree sequences, and show that the switch chain
is rapidly mixing for these families.
We further extend these notions and results to directed degree sequences.
Chinese: 交换链是一个研究得很好的马尔可夫链，可用于从具有给定度序列 $\boldsymbol{d}$ 的所有图构成的集合 $\Omega(\boldsymbol{d})$ 中近似均匀地采样。在各种度序列条件下，已经为交换链建立了多项式混合时间（快速混合）。Amanatidis和Kleer引入了度序列强稳定性的概念，并证明了对于强稳定度序列集中的任何度序列，交换链都是快速混合的。采用不同的方法，Erd\H{o}s等人最近将这一结果扩展到Jerrum和Sinclair于1990年引入的（可能更大的）P-稳定性度序列类。我们为给定的度序列定义了一个新的稳定性概念，即$k$-\emph{稳定性}，并证明了如果度序列 $\boldsymbol{d}$ 是8-稳定的，那么交换链在 $\Omega(\boldsymbol{d})$ 上是快速混合的。我们还提供了P稳定性、强稳定性和8稳定性的充分条件。利用这些充分条件，我们首次为各种重尾度序列族（包括幂律度序列族）证明了P稳定性，并表明对于这些族，交换链是快速混合的。
我们进一步将这些概念和结果扩展到有向度序列。
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English: We give the solution of the Monge-Kantorovitch problem on the Wiener space
for the singular Wasserstein metric which is defined with respect to the
distance of the underlying Cameron-Martin space. We show, under the hypothesis
that this distance is finite, the existence and the uniquness of the solutions,
that they are supported by the graphs of the weak derivatives of H-convex
Wiener functionals. then we prove the more general situation, where the
measures are not even necessarily absolutely continuous w.r.to the Wiener
measure. We give sufficient conditions for the hypothesis about the Wassestein
distance is finite with the help of the Girsanov theorem. Finally we give the
solutions of the Monge-Ampere equation using the classical Jacobi
representation and/or the Ito parametrization of the Wiener space.
Chinese: 我们给出了Wiener空间上关于奇异Wasserstein度量的Monge-Kantorovitch问题的解，该度量是相对于底层Cameron-Martin空间的距离定义的。我们证明了，在假设这种距离是有限的情况下，解的存在性和唯一性，以及它们是由H-凸Wiener泛函的弱导数的图形支持的。然后我们证明了更一般的情况，其中度量甚至不一定是相对于Wiener测度绝对连续的。我们借助Girsanov定理给出了关于Wasserstein距离有限的假设的充分条件。最后，我们使用经典的Jacobi表示和/或Wiener空间的Ito参数化给出了Monge-Ampere方程的解。
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English: In a recent table-top experiment we demonstrated the compatibility of three
advanced interferometer techniques for gravitational wave detection, namely
power-recycling, detuned signal-recycling and squeezed field injection. The
interferometer's signal to noise ratio was improved by up to 2.8 dB beyond the
coherent state's shot-noise. This value was mainly limited by optical losses on
the squeezed field. We present a detailed analysis of the optical losses of in
our experiment and provide an estimation of the possible nonclassical
performance of a future squeezed field enhanced GEO600 detector.
Chinese: 在最近的一个桌面实验中，我们展示了三种用于探测引力波的高级干涉仪技术的兼容性，即功率回收、信号回收和相干态压缩场注入。干涉仪的信噪比提高了2.8 dB，这主要是由于压缩场的光学损失所限制的。我们提供了实验中光学损失的详细分析，并对未来压缩场增强的GEO600探测器的可能非经典性能进行了估计。
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English: Often, the storage and computational constraints of embeddeddevices demand
that a single on-device ASR model serve multiple use-cases / domains. In this
paper, we propose aFlexibleTransducer(FlexiT) for on-device automatic speech
recognition to flexibly deal with multiple use-cases / domains with different
accuracy and latency requirements. Specifically, using a single compact model,
FlexiT provides a fast response for voice commands, and accurate transcription
but with more latency for dictation. In order to achieve flexible and better
accuracy and latency trade-offs, the following techniques are used. Firstly, we
propose using domain-specific altering of segment size for Emformer encoder
that enables FlexiT to achieve flexible de-coding. Secondly, we use Alignment
Restricted RNNT loss to achieve flexible fine-grained control on token emission
latency for different domains. Finally, we add a domain indicator vector as an
additional input to the FlexiT model. Using the combination of techniques, we
show that a single model can be used to improve WERs and real time factor for
dictation scenarios while maintaining optimal latency for voice commands
use-cases
Chinese: 通常，嵌入式设备的存储和计算限制要求单个设备上的自动语音识别（ASR）模型服务于多个用例/领域。在本文中，我们提出了一种灵活的转换器（FlexiT），用于设备上的自动语音识别，以灵活地处理具有不同精度和延迟要求的多个用例/领域。具体来说，使用单个紧凑模型，FlexiT可以为语音命令提供快速响应，并实现准确的转录，但为口述提供了更多的延迟。为了实现灵活的以及更好的精度和延迟权衡，采用了以下技术。首先，我们提出使用针对特定领域的段大小调整Emformer编码器，使FlexiT能够实现灵活的解码。其次，我们使用对齐限制的RNNT损失，以实现对不同领域标记发射延迟的灵活细粒度控制。最后，我们将一个领域指示向量作为额外的输入添加到FlexiT模型中。通过技术的组合，我们表明单个模型可以用于提高口述场景的词错误率（WER）和实时因子，同时保持语音命令用例的最优延迟。
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English: Superfluid $^{3}$He experiments show strong deviation from the weak-coupling
limit of the Ginzburg-Landau theory, and this discrepancy grows with increasing
pressure. Strong-coupling contributions to the quasiparticle interactions are
known to account for this effect and they are manifest in the five
$\beta$-coefficients of the fourth order Ginzburg-Landau free energy terms. The
Ginzburg-Landau free energy also has a coefficient $g_{z}$ to include magnetic
field coupling to the order parameter. From NMR susceptibility experiments, we
find the deviation of $g_{z}$ from its weak-coupling value to be negligible at
all pressures. New results for the pressure dependence of four different
combinations of $\beta$-coefficients, $\beta$_{345}, $\beta$_{12},
$\beta$_{245}, and $\beta$_{5} are calculated and comparison is made with
theory.
Chinese: 超流 $^{3}$He 实验表明，其与 Ginzburg-Landau 理论的弱耦合极限存在显著偏差，并且这种偏差随着压力的增加而增大。已知强耦合对准粒子相互作用的贡献可以解释这一效应，并且它们在四阶 Ginzburg-Landau 自由能项的五个 $\beta$ 系数中表现出来。Ginzburg-Landau 自由能还有一个系数 $g_{z}$，用于包括磁场与序参数的耦合。从核磁共振磁化率实验中，我们发现 $g_{z}$ 与其弱耦合值的偏差在所有压力下都可以忽略不计。计算了四个不同 $\beta$ 系数组合的压力依赖性新结果，即 $\beta$_{345}、$\beta$_{12}、$\beta$_{245} 和 $\beta$_{5}，并与理论进行了比较。
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English: One of the most popular approaches to understanding feature effects of modern
black box machine learning models are partial dependence plots (PDP). These
plots are easy to understand but only able to visualize low order dependencies.
The paper is about the question 'How much can we see?': A framework is
developed to quantify the explainability of arbitrary machine learning models,
i.e. up to what degree the visualization as given by a PDP is able to explain
the predictions of the model. The result allows for a judgement whether an
attempt to explain a black box model is sufficient or not.
Chinese: 理解现代黑盒机器学习模型特征效应的最流行方法之一是部分依赖图（PDP）。这些图易于理解，但只能可视化低阶依赖关系。本文探讨的问题是"我们能看到多少？": 开发了一个框架来量化任意机器学习模型的可解释性，即由PDP提供的可视化结果能够在多大程度上解释模型的预测。该结果允许判断解释黑盒模型的努力是否充分。
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English: It is well known that the vacuum in the Einstein gravity, which is linear in
the Riemann curvature, is trivial in the critical (2+1=3) dimension because
vacuum solution is flat. It turns out that this is true in general for any odd
critical $d=2n+1$ dimension where $n$ is the degree of homogeneous polynomial
in Riemann defining its higher order analogue whose trace is the nth order
Lovelock polynomial. This is the "curvature" for nth order pure Lovelock
gravity as the trace of its Bianchi derivative gives the corresponding analogue
of the Einstein tensor \cite{bianchi}. Thus the vacuum in the pure Lovelock
gravity is always trivial in the odd critical (2n+1) dimension which means it
is pure Lovelock flat but it is not Riemann flat unless $n=1$ and then it
describes a field of a global monopole. Further by adding Lambda we obtain the
Lovelock analogue of the BTZ black hole.
Chinese: 众所周知，在爱因斯坦引力中，真空解与黎曼曲率线性相关，在临界维度（2+1=3）中是平凡的，因为真空解是平直的。结果发现，这在任何奇数临界维度$d=2n+1$中都是普遍成立的，其中$n$是定义黎曼曲率的高阶类似物的齐次多项式的次数，其迹是第$n$阶洛夫洛克多项式。这是第$n$阶纯洛夫洛克引力的“曲率”，因为其比安基导数的迹给出了对应的爱因斯坦张量的类似物\cite{bianchi}。因此，纯洛夫洛克引力在奇数临界维度（2n+1）中的真空总是平凡的，这意味着它是纯洛夫洛克平直的，但除非$n=1$，否则它不是黎曼平直的；当$n=1$时，它描述了一个全局单极子的场。进一步地，通过添加$\Lambda$，我们得到了BTZ黑洞的洛夫洛克类似物。
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English: The string-matching problem, ubiquitous in computer science, can
significantly benefit from quantum algorithms due to their potential for
greater efficiency compared to classical approaches. The practical
implementation of the quantum string matching (QSM) algorithm requires
fault-tolerant quantum computation due to the fragility of quantum information.
A major obstacle in implementing fault-tolerant quantum computation is the high
cost associated with executing T gates. This paper introduces the
relative-phase Fredkin gate as a strategy to notably reduce the number of T
gates (T-count) necessary for the QSM algorithm. This reduces the T-count from
14N^(3/2) log_2 N-O(N^(3/2)) to 8N^(3/2) log_2 N-O(N^(3/2)), where N represents
the size of the database to be searched. Additionally, we demonstrate that our
method is advantageous in terms of other circuit costs, such as the depth of T
gates and the number of CNOT gates. This advancement contributes to the ongoing
development of the QSM algorithm, paving the way for more efficient solutions
in the field of computer science.
Chinese: 字符串匹配问题，在计算机科学中普遍存在，由于量子算法在效率上可能远超经典方法，因此在量子计算背景下，该问题能显著受益。实现量子字符串匹配（QSM）算法的实用实施需要容错量子计算，因为量子信息非常脆弱。实现容错量子计算的主要障碍之一是执行T门的高成本。本文引入相对相位弗雷德金门作为策略，显著减少了QSM算法所需的T门数量（T-count）。这将T-count从14N^(3/2) log_2 N-O(N^(3/2))减少到8N^(3/2) log_2 N-O(N^(3/2))，其中N表示要搜索的数据库大小。此外，我们证明了我们的方法在其他电路成本方面，如T门的深度和CNOT门的数量上具有优势。这一进展对QSM算法的持续发展做出了贡献，为计算机科学领域更高效的解决方案铺平了道路。
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English: Word error rate (WER) and character error rate (CER) are standard metrics in
Speech Recognition (ASR), but one problem has always been alternative
spellings: If one's system transcribes adviser whereas the ground truth has
advisor, this will count as an error even though the two spellings really
represent the same word.
Japanese is notorious for ``lacking orthography'': most words can be spelled
in multiple ways, presenting a problem for accurate ASR evaluation. In this
paper we propose a new lenient evaluation metric as a more defensible CER
measure for Japanese ASR. We create a lattice of plausible respellings of the
reference transcription, using a combination of lexical resources, a Japanese
text-processing system, and a neural machine translation model for
reconstructing kanji from hiragana or katakana. In a manual evaluation, raters
rated 95.4% of the proposed spelling variants as plausible. ASR results show
that our method, which does not penalize the system for choosing a valid
alternate spelling of a word, affords a 2.4%-3.1% absolute reduction in CER
depending on the task.
Chinese: 词语错误率（WER）和字符错误率（CER）是语音识别（ASR）中的标准指标，但是一直存在的问题是不同的拼写方式：如果某个系统将advisor转录为adviser，而真实情况是advisor，这将被计为错误，尽管这两种拼写实际上代表的是同一个词。日语因其“缺乏正字法”而臭名昭著：大多数单词可以有多种拼写方式，这给准确的ASR评估带来了问题。在本文中，我们提出了一种新的宽容评估指标，作为日语ASR中更具防御性的CER度量。我们创建了一个参考转录可能重拼的格网，结合了词汇资源、一个日语文本处理系统以及一个用于从平假名或片假名重建汉字的神经机器翻译模型。在人工评估中，评分者将95.4%的提议拼写变体评为可能的。ASR结果表明，我们的方法，即不对系统选择一个单词的有效替代拼写进行惩罚，根据任务的不同，CER绝对降低了2.4%-3.1%。
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English: We prove that the 1D Schr\"odinger equation with derivative in the nonlinear
term is globally well-posed in $H^{s}$, for $s>2/3$ for small $L^{2}$ data. The
result follows from an application of the ``I-method''. This method allows to
define a modification of the energy norm $H^{1}$ that is ``almost conserved''
and can be used to perform an iteration argument. We also remark that the same
argument can be used to prove that any quintic nonlinear defocusing
Schr\"odinger equation on the line is globally well-posed for large data in
$H^{s}$, for $s>2/3$ .
Chinese: 我们证明，对于小规模的$L^{2}$数据，具有非线性项导数的1D薛定谔方程在$H^{s}$空间中全局有界，当$s>2/3$时。这一结果源于对“$I$方法”的应用。这种方法允许定义一个修改后的能量范数$H^{1}$，该范数是“几乎守恒”的，并且可以用于进行迭代论证。我们还指出，同样的论证可以用来证明任何一线性五次非线性非聚焦薛定谔方程在$H^{s}$空间中对于大数据全局有界，当$s>2/3$时。
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English: We study one-dimensional motions of polytropic gas governed by the
compressible Euler equations. The problem on the half space under a constant
gravity gives an equilibrium which has free boundary touching the vacuum and
the linearized approximation at this equilibrium gives time periodic solutions.
But it is not easy to justify the existence of long-time true solutions for
which this time periodic solution is the first approximation. The situation is
in contrast to the problem of free motions without gravity. The reason is that
the usual iteration method for quasilinear hyperbolic problem cannot be used
because of the loss of regularities which causes from the touch with the
vacuum. Interestingly, the equation can be transformed to a nonlinear wave
equation on a higher dimensional space, for which the space dimension, being
larger than 4, is related to the adiabatic exponent of the original
one-dimensional problem. We try to find a family of solutions expanded by a
small parameter. Applying the Nash-Moser theory, we justify this expansion.The
application of the Nash-Moser theory is necessary for the sake of conquest of
the trouble with loss of regularities, and the justification of the
applicability requires a very delicate analysis of the problem.
Chinese: 我们研究多态气体在一维下的运动，这些运动由可压缩欧拉方程组所控制。在半空间下受恒定重力作用的定态问题提供了一个自由边界与真空接触的平衡状态，在这个平衡状态下进行的线性化近似给出了时间周期解。但要证明存在长时间真实解，其中这个时间周期解作为第一级近似，则并不容易。与无重力自由运动问题的情况相反，原因在于通常用于拟线性双曲型问题的迭代方法不能使用，因为与真空接触会导致正则性的损失。有趣的是，这个方程可以变换到更高维空间上的非线性波动方程，其中空间维度，由于大于4，与原问题的单维问题的绝热指数有关。我们尝试找到一个以小参数为展开的解的家族。应用Nash-Moser理论，我们证明了这一展开。
应用Nash-Moser理论是必要的，以克服正则性损失的困难，而证明适用性需要非常精细的问题分析。
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English: In this paper, we study commutative zero-divisor semigroups determined by
graphs. We prove a uniqueness theorem for a class of graphs. We show two
classes of graphs that have no corresponding semigroups. In particular, any
complete graph $K_n$ together with more than three end vertices and any
complete bipartite graph together with more than one end vertices have no
corresponding semigroups. We also determine all possible zero-divisor
semigroups whose zero-divisor graph is the com- plete graph $K_3$ together with
two end vertices.
Chinese: 在本文中，我们研究由图决定的交换零因子半群。我们证明了一类图的唯一性定理。我们表明有两类图没有对应的半群。特别是，任何具有超过三个端点的完全图$K_n$以及任何具有超过一个端点的完全二部图都没有对应的半群。我们还确定了所有可能的零因子半群，其零因子图是完全图$K_3$与两个端点。
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English: When testing a set of data for randomness according to a probability
distribution that depends on a parameter, access to this parameter can be
considered as a computational resource. We call a randomness test Hippocratic
if it is not permitted to access this resource. In these terms, we show that
for Bernoulli measures $\mu_p$, $0\le p\le 1$ and the Martin-L\"of randomness
model, Hippocratic randomness of a set of data is the same as ordinary
randomness. The main idea of the proof is to first show that from
Hippocrates-random data one can Turing compute the parameter $p$. However, we
show that there is no single Hippocratic randomness test such that passing the
test implies computing $p$, and in particular there is no universal Hippocratic
randomness test.
Chinese: 在根据依赖于参数的概率分布来测试数据集是否随机的过程中，访问这个参数可以被视为一种计算资源。我们称一个随机性测试为希波克拉底测试，如果它不允许访问这个资源。按照这些术语，我们表明对于伯努利度量$\mu_p$，$0\le p\le 1$以及马丁-洛夫随机性模型，数据集的希波克拉底随机性等同于普通随机性。证明的主要思想是首先证明从希波克拉底随机数据可以图灵计算参数$p$。然而，我们表明不存在单一的希波克拉底随机性测试，使得通过测试意味着计算$p$，特别是不存在通用希波克拉底随机性测试。
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English: We present a new method to transform an expanded class of non-selfadjoint
advection-diffusion operators into self-adjoint operators. The transform is
based on a combination of a point transform and Lie transform in conjunction
with an asymptotic expansion in terms of the diffusivity. We illustrate the
method in the context of simple shear flow where the expansion is exact and all
transformation steps can be performed explicitly.
Chinese: 我们提出了一种将一类非自伴对流扩散算子转化为自伴算子的新方法。该变换基于点变换和Lie变换的组合，并结合扩散率的渐近展开。我们在简单剪切流的背景下说明了该方法，在该背景下展开是精确的，并且所有变换步骤都可以明确执行。
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English: We present observations of SCP 06F6, an unusual optical transient discovered
during the Hubble Space Telescope Cluster Supernova Survey. The transient
brightened over a period of ~100 days, reached a peak magnitude of ~21.0 in
both i_775 and z_850, and then declined over a similar timescale. There is no
host galaxy or progenitor star detected at the location of the transient to a 3
sigma upper limit of i_775 = 26.4 and z_850 = 26.1, giving a corresponding
lower limit on the flux increase of a factor of ~120. Multiple spectra show
five broad absorption bands between 4100 AA and 6500 AA and a mostly
featureless continuum longward of 6500 AA. The shape of the lightcurve is
inconsistent with microlensing. The transient's spectrum, in addition to being
inconsistent with all known supernova types, is not matched to any spectrum in
the Sloan Digital Sky Survey (SDSS) database. We suggest that the transient may
be one of a new class.
Chinese: 我们展示了对SCP 06F6的观测结果，这是一个在哈勃太空望远镜星团超新星调查中发现的不寻常的光学瞬变体。该瞬变体在约100天的时间内变亮，在i_775和z_850波段均达到峰值星等~21.0，然后又在这个相似的时间尺度上变暗。在瞬变体的位置没有探测到宿主星系或前体恒星，其i_775波段的上限为26.4，z_850波段的上限为26.1，这给出了相应的通量增加下限约为120倍。多个光谱显示在4100 Å到6500 Å之间有五个宽吸收带，而在6500 Å之后的光谱连续谱几乎没有特征。该瞬变体的光变曲线形状与微引力透镜效应不符。除了与所有已知超新星类型都不符之外，该瞬变体的光谱也没有与斯隆数字天空调查（SDSS）数据库中的任何光谱相匹配。我们建议该瞬变体可能属于一种新的类型。
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English: In recent work, we developed a method to construct invertible and
non-invertible symmetries of finite-group gauge theories as topological domain
walls on the lattice. In the present work, we consider abelian and non-abelian
finite-group gauge theories in general spacetime dimension, and demonstrate how
to realize these symmetries as condensation defects, i.e., as suitable
insertions of lower dimensional topological operators. We then compute the
fusion rules and action of these symmetries using their condensation expression
and the algebraic properties of the lower dimensional objects that make them.
We illustrate the discussion in $\mathbb{Z}_N$ gauge theory, where we derive
the correspondence between domain walls, labeled by subgroups and actions for
the doubled gauge group, and higher gauging condensation defects, labeled by
subalgebras of the global symmetry. As a primary application, we obtain the
condensation expression for the invertible symmetries of abelian gauge theories
defined by outer automorphisms of the gauge group. We also show how to use
these ideas to derive the action for certain non-abelian groups. For instance,
one can obtain the action for the Dihedral group $\mathbb{D}_4$ by gauging a
swap symmetry of $\mathbb{Z}_2\times\mathbb{Z}_2$ gauge theory.
Chinese: 在最近的工作中，我们发展了一种构建有限群规范理论的可逆和非可逆对称性的方法，这些对称性作为拓扑域墙出现在格子上。在本文中，我们考虑一般时空维度的可交换和不可交换有限群规范理论，并展示如何实现这些对称性作为凝聚缺陷，即作为适合插入的低维拓扑运算符的适当插入。然后我们使用凝聚表达和这些低维对象使其成为的代数性质来计算这些对称性的融合规则和作用。我们通过 $\mathbb{Z}_N$ 规范理论来阐明讨论，其中我们推导了域墙与双倍规范群的子群和作用之间的对应关系，以及全局对称性的子代数标记的高阶凝聚缺陷。作为一个主要应用，我们得到了由规范群的群外自同构定义的交换对称性的凝聚表达式。我们还展示了如何使用这些想法来推导某些非交换群的作用。例如，通过规范 $\mathbb{Z}_2\times\mathbb{Z}_2$ 规范理论的交换对称性，可以推导出二面体群 $\mathbb{D}_4$ 的作用。
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English: We reconsider the study of the geometric transitions and brane/flux dualities
in various dimensions. We first give toric interpretations of the topology
changing transitions in the Calabi-Yau conifold and the $Spin(7)$ manifold. The
latter, for instance, can be viewed as three intersecting Calabi-Yau conifolds
according to $\cp^2$ toric graph. Orbifolds of such geometries are given in
terms of del Pezzo complex surfaces. Second we propose a four-dimensional
F-theory interpretation of type IIB geometric transitions on the Calabi-Yau
conifold. This gives a dual description of the M-theory flop in terms of toric
mirror symmetry. In two dimensions, we study the geometric transition in a
singular $Spin(7)$ manifold constructed as a cone on SU(3)/U(1). In particular,
we discuss brane/flux duality in such a compactification in both type IIA and
type IIB superstrings. These examples preserve one supercharge and so have
${\cal N}= 1/2$ supersymmetry in two dimensions. Then, an interpretation in
terms of F-theory is given.
Chinese: 我们重新考虑了在不同维度下几何过渡和膜/流形对称性的研究。首先，我们给出了Calabi-Yau锥体和$Spin(7)$流形拓扑变化过渡的拓扑解释。例如，根据$\cp^2$拓扑图，后者可以被视为三个相交的Calabi-Yau锥体。这些几何的对偶形式可以用del Pezzo复曲面来表示。其次，我们提出了在Calabi-Yau锥体上，四维F理论对IIB几何过渡的解释。这给出了M理论翻转的对偶描述，基于托里奇镜对称。在二维中，我们研究了作为SU(3)/U(1)锥体构造的奇异$Spin(7)$流形上的几何过渡。特别是，我们讨论了在两种类型的超弦（IAA和IIB）中这种紧致化过程中的膜/流形对称性。这些例子保持了一个超荷，因此在二维中具有${\cal N}= 1/2$超对称性。然后，我们给出了F理论的解释。
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English: While Reinforcement Learning ( RL) has made great strides towards solving
increasingly complicated problems, many algorithms are still brittle to even
slight environmental changes. Contextual Reinforcement Learning (cRL) provides
a framework to model such changes in a principled manner, thereby enabling
flexible, precise and interpretable task specification and generation. Our goal
is to show how the framework of cRL contributes to improving zero-shot
generalization in RL through meaningful benchmarks and structured reasoning
about generalization tasks. We confirm the insight that optimal behavior in cRL
requires context information, as in other related areas of partial
observability. To empirically validate this in the cRL framework, we provide
various context-extended versions of common RL environments. They are part of
the first benchmark library, CARL, designed for generalization based on cRL
extensions of popular benchmarks, which we propose as a testbed to further
study general agents. We show that in the contextual setting, even simple RL
environments become challenging - and that naive solutions are not enough to
generalize across complex context spaces.
Chinese: 虽然强化学习（RL）在解决日益复杂的问题上取得了巨大进步，但许多算法对环境中的微小变化仍然非常脆弱。上下文强化学习（cRL）提供了一个框架，以原则性的方式模拟这些变化，从而实现灵活、精确和可解释的任务规范和生成。我们的目标是展示cRL框架如何通过有意义的基准和关于泛化任务的有序推理来提高RL中的零样本泛化能力。我们证实了这样的见解：在cRL中，最优行为需要上下文信息，正如其他部分可观察性的相关领域一样。为了在cRL框架中实证验证这一点，我们提供了各种扩展上下文的常见RL环境版本。它们是第一个基准库CARL的一部分，该库基于对流行基准的cRL扩展而设计，我们将其作为进一步研究通用代理的测试平台。我们表明，在上下文设置中，即使是简单的RL环境也变得具有挑战性——而简单的解决方案不足以在复杂上下文空间中进行泛化。
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English: Motivated by numerical continuation studies of coupled mechanical
oscillators, we investigate branches of localized time-periodic solutions of
one-dimensional chains of coupled oscillators. We focus on Ginzburg--Landau
equations with nonlinearities of Lambda-Omega type and establish the existence
of localized synchrony patterns in the case of weak coupling and weak-amplitude
dependence of the oscillator periods. Depending on the coupling, localized
synchrony patterns lie on a discrete stack of isola branches or on a single
connected snaking branch.
Chinese: 受耦合机械振荡器数值延拓研究的启发，我们研究了一维耦合振荡器链的局域化时间周期解分支。我们关注具有Lambda-Omega型非线性的Ginzburg-Landau方程，并在振荡器周期对振幅的依赖性较弱的情况下，证明了局域同步模式的存在性。根据耦合强度，局域同步模式位于离散的孤立分支堆栈上，或位于单条连通的蛇形分支上。
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English: Effects of heterogeneity in the suspected-infected-susceptible model on
networks are investigated using quenched mean-field theory. The emergence of
localization is described by the distributions of the inverse participation
ratio and compared with the rare-region effects appearing in simulations and in
the Lifschitz tails. The latter, in the linear approximation, is related to the
spectral density of the Laplacian matrix and to the time dependent order
parameter. I show that these approximations indicate correctly Griffiths Phases
both on regular one-dimensional lattices and on small world networks exhibiting
purely topological disorder. I discuss the localization transition that occurs
on scale-free networks at $\gamma=3$ degree exponent.
Chinese: 使用淬火平均场理论研究了在网络上疑似感染易感模型中异质性的影响。局域化的出现由逆参与比率的分布来描述，并与模拟和Lifschitz尾部中出现的稀疏区域效应进行比较。后者在线性近似中与拉普拉斯矩阵的谱密度以及时间依赖的序参量相关。我表明，这些近似正确地指示了在规则的一维晶格和表现出纯粹拓扑无序的小世界网络上的Griffiths相。我讨论了在γ=3度指数的尺度自由网络上发生的局域化转变。
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English: We investigate cross-quality knowledge distillation (CQKD), a knowledge
distillation method where knowledge from a teacher network trained with
full-resolution images is transferred to a student network that takes as input
low-resolution images. As image size is a deciding factor for the computational
load of computer vision applications, CQKD notably reduces the requirements by
only using the student network at inference time. Our experimental results show
that CQKD outperforms supervised learning in large-scale image classification
problems. We also highlight the importance of calibrating neural networks: we
show that with higher temperature smoothing of the teacher's output
distribution, the student distribution exhibits a higher entropy, which leads
to both, a lower calibration error and a higher network accuracy.
Chinese: 我们研究了跨质量知识蒸馏（CQKD），这是一种知识蒸馏方法，其中从使用全分辨率图像训练的教师网络中提取的知识被传递到以低分辨率图像作为输入的学生网络。由于图像大小是计算机视觉应用计算负载的决定性因素，CQKD显著降低了要求，仅在推理时使用学生网络。我们的实验结果表明，CQKD在大型图像分类问题中优于监督学习。我们还强调了校准神经网络的重要性：我们表明，通过教师输出分布的更高温度平滑，学生的分布表现出更高的熵，这导致校准误差更低和网络精度更高。
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English: A highly sensitive refractive index sensor based on grating-assisted strip
waveguide directional coupler is proposed. The sensor is designed using two
coupled asymmetric strip waveguides with a top-loaded grating structure in one
of the waveguides. Maximum light couples from one waveguide to the other at the
resonance wavelength, and the change in resonance wavelength with the change in
refractive index of the medium in the cover region is a measure of the
sensitivity. The proposed sensor would be an on-chip device with a high
refractive index sensitivity of ~ 104 nm/RIU, and negligible temperature
sensitivity (< 1nm/0C). The sensor configuration offers a low propagation loss,
thereby enhancing the sensitivity. Variation of the sensitivity with the
waveguide parameters of the proposed sensor have been studied to optimize the
design.
Chinese: 一种基于光栅辅助条形波导方向耦合器的高度灵敏折射率传感器被提出。该传感器采用两个耦合的非对称条形波导，其中一个波导中具有顶部加载的光栅结构。在谐振波长处，最大光从一条波导耦合到另一条波导，而覆盖区域介质折射率的变化与谐振波长的变化是灵敏度的衡量标准。所提出的传感器将是一个芯片上的设备，具有高达 ~ 104 nm/RIU 的折射率灵敏度，并且温度灵敏度可忽略不计（< 1nm/0C）。该传感器配置提供了低传播损耗，从而增强了灵敏度。已经研究了所提出的传感器的波导参数与灵敏度变化的关系，以优化设计。
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English: Trapped atomic ion crystals are a leading platform for quantum simulations of
spin systems, with programmable and long-range spin-spin interactions mediated
by excitations of phonons in the crystal. We describe a complementary approach
for quantum simulations of bosonic systems using phonons in trapped-ion
crystals, here mediated by excitations of the trapped ion spins. The scheme
features a high degree of programability over a dense graph of bosonic
couplings and is suitable for hard problems such as boson sampling and
simulations of long range bosonic and spin-boson Hamiltonians.
Chinese: 被捕获的原子离子晶体是量子模拟自旋系统的领先平台，通过晶体内声子的激发介导可编程和长程的自旋-自旋相互作用。我们描述了一种互补的方法，用于利用被捕获离子晶体中的声子进行玻色子系统的量子模拟，该方法是通过被捕获离子自旋的激发来实现的。该方案在玻色子耦合的密集图中具有高度的编程能力，并且适用于玻色子采样以及模拟长程玻色子和自旋-玻色子哈密顿量等难题。
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English: The Web of Life (www.web-of-life.es) provides a graphical user interface,
based on Google Maps, for easily visualizing and downloading data on ecological
networks of species interactions. It is designed and implemented in a
relational database management system, allowing sophisticated and user-friendly
searching across networks. Users can access the database by any web browser
using a variety of operating systems. Data can be downloaded in several common
formats, and a data transmission webservice in JavaScript Object Notation is
also provided.
Chinese: 生命之网（www.web-of-life.es）提供了一个基于谷歌地图的图形用户界面，用于轻松可视化并下载物种相互作用生态网络的数据。它设计并实现在一个关系型数据库管理系统上，允许在网络上进行复杂且用户友好的搜索。用户可以通过任何支持多种操作系统的网络浏览器访问数据库。数据可以以几种常见的格式下载，并提供了一个基于JavaScript对象表示法的Web服务数据传输。
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English: Extra cellular alkaline protease producing species is an isolate from soil
which was characterized and identified as Streptomyces pulvereceus MTCC 8374.
Studies on submerged fermentation revealed that maximum level of enzyme
production was during early stationary phase. Optimum pH, inoculum and
temperature were 9.0, 3 percent and 33 C respectively. Among carbon sources 0.3
peccent starch gave a maximum production followed by maltose, xylose and
fructose. High yield of protease production was reported with 1.0 percent
casein followed by soybean meal, yeast extract and malt extract. Further, it
was optimized with 0.5 percent, 1.0 percentand 1.5 percent of NaCl among which
1 percent NaCl resulted in maximum level of protease. The protease profile of
the isolate shows its potential as a good source for industrial application.
Chinese: 产生胞外碱性蛋白酶的物种是一种从土壤中分离的菌株，该菌株被鉴定为Streptomyces pulvereceus MTCC 8374。对深层发酵的研究表明，酶产量的最大值出现在稳定期的早期。最适pH值、接种量和温度分别为9.0、3%和33°C。在碳源中，0.3%的淀粉产生了最高的产量，其次是麦芽糖、木糖和果糖。报告称，1.0%的酪蛋白产生了高蛋白酶产量，其次是豆粕、酵母提取物和麦芽提取物。进一步优化后，使用0.5%、1.0%和1.5%的NaCl，其中1%的NaCl导致蛋白酶产量达到最大值。该菌株的蛋白酶特性表明，它具有作为工业应用良好来源的潜力。
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English: Extremely magnetized neutron stars with magnetic fields as strong as $\sim
10^{15-16}$ G, or magnetars, have received considerable attention in the last
decade due to their identification as a plausible source for Soft Gamma
Repeaters and Anomalous X-ray Pulsars. Moreover, this class of compact objects
has been proposed as a possible engine capable of powering both Long and Short
Gamma-Ray Bursts, if the rotation period in their formation stage is short
enough (~1 ms). Such strong fields are expected to induce substantial
deformations of the star and thus to produce the emission of gravitational
waves. Here we investigate, by means of numerical modeling, axisymmetric static
equilibria of polytropic and strongly magnetized stars in full general
relativity, within the ideal magneto-hydrodynamic regime. The eXtended
Conformally Flat Condition (XCFC) for the metric is assumed, allowing us to
employ the techniques introduced for the X-ECHO code [Bucciantini & Del Zanna,
2011, Astron. Astrophys. 528, A101], proven to be accurate, efficient, and
stable. The updated XNS code for magnetized neutron star equilibria is made
publicly available for the community (see
www.arcetri.astro.it/science/ahead/XNS). Several sequences of models are here
retrieved, from the purely toroidal (resolving a controversy in the literature)
or poloidal cases, to the so-called twisted torus mixed configurations,
expected to be dynamically stable, which are solved for the first time in the
non-perturbative regime.
Chinese: 具有高达$\sim 10^{15-16}$ 高斯（G）的强磁场的中子星，即磁星，在过去十年中受到了广泛关注，因为它们被认为是软伽马重复器和异常X射线脉冲星的一种可能来源。此外，这类致密天体还被提议为一种可能引擎，能够驱动长时标和短时标伽马射线暴，前提是它们在形成阶段的自转周期足够短（约1毫秒）。如此强的磁场预计将导致恒星发生显著变形，从而产生引力波。在这里，我们通过数值模拟方法，在全广义相对论框架下，在理想磁流体动力学范围内研究了多极性和强磁场恒星的对称静态平衡。假设度规满足扩展平坦条件（XCFC），使我们能够采用为X-ECHO代码[Giulio Bucciantini & Gianluca Del Zanna, 2011, Astron. Astrophys. 528, A101]引入的技术，该技术已被证明是精确、高效且稳定的。更新的用于磁化中子星平衡的XNS代码已向社区公开（见www.arcetri.astro.it/science/ahead/XNS）。这里检索了多个模型序列，从纯环向（解决文献中的一场争议）或极向情况，到所谓的扭曲环向混合配置，预计是动力学稳定的，这些配置在非扰动状态下首次得到求解。
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English: A recent debate has ensued over the claim by Pikovski et al. [Nat. Phys. 11,
668 (2015)] that systems with internal degrees of freedom undergo a universal,
gravity-induced, type of decoherence that explains their quantum-to-classical
transition. This decoherence is supposed to arise from the different
gravitational redshifts experienced by such systems when placed in a
superposition of two wave packets at different heights in a gravitational
field. Here we investigate some aspects of the discussion with the aid of
simple examples. In particular, we first resolve an apparent conflict between
the reported results and the equivalence principle by noting that the static
and free-fall descriptions focus on states associated with different
hypersurfaces. Next, we emphasize that predictions regarding the observability
of interference become relevant only in the context of concrete experimental
settings. As a result, we caution against hasty claims of universal validity.
Finally, we dispute the claim that, at least in the scenarios discussed by
Pikovski et al., gravitation is responsible for the reported results, and we
question the alleged ability of decoherence to explain the quantum-to-classical
transition. In consequence, we argue against the extraordinary assertion by
Pikovski et al. that gravity can account for the emergence of classicality.
Chinese: 最近，关于Pikovski等人[Nat. Phys. 11, 668 (2015)]提出的声称，具有内部自由度的系统经历了一种普遍的、由引力引起的退相干类型，这种退相干解释了它们的量子到经典过渡。这种退相干被认为源于当这些系统被放置在重力场中不同高度的波包叠加中时，所经历的不同引力红移。在这里，我们借助简单的例子来探讨讨论的一些方面。特别是，我们首先通过注意到静态和自由落体描述关注的是与不同超曲面相关的状态，从而解决了报告结果与等效原理之间明显的冲突。接下来，我们强调，关于可观测性干涉的预测只有在具体的实验设置背景下才变得相关。因此，我们警告不要匆忙地声称普遍有效性。最后，我们质疑Pikovski等人声称的引力至少在讨论的场景中负责报告结果，并质疑退相干解释量子到经典过渡的能力。因此，我们反对Pikovski等人提出的非凡断言，即引力可以解释经典性的出现。
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English: Analysts often make visual causal inferences about possible data-generating
models. However, visual analytics (VA) software tends to leave these models
implicit in the mind of the analyst, which casts doubt on the statistical
validity of informal visual "insights". We formally evaluate the quality of
causal inferences from visualizations by adopting causal support -- a Bayesian
cognition model that learns the probability of alternative causal explanations
given some data -- as a normative benchmark for causal inferences. We
contribute two experiments assessing how well crowdworkers can detect (1) a
treatment effect and (2) a confounding relationship. We find that chart users'
causal inferences tend to be insensitive to sample size such that they deviate
from our normative benchmark. While interactively cross-filtering data in
visualizations can improve sensitivity, on average users do not perform
reliably better with common visualizations than they do with textual
contingency tables. These experiments demonstrate the utility of causal support
as an evaluation framework for inferences in VA and point to opportunities to
make analysts' mental models more explicit in VA software.
Chinese: 分析师们经常对可能的数据生成模型做出视觉因果推断。然而，视觉分析（VA）软件往往将这些模型隐含在分析师的思维中，这引发了人们对非正式视觉“洞察”的统计有效性的怀疑。我们通过采用因果支持——一种给定某些数据学习替代因果解释概率的贝叶斯认知模型——作为因果推断的规范性基准，正式评估了从可视化中得出的因果推断的质量。我们贡献了两个实验，评估了众包工作者如何检测（1）治疗效果和（2）混杂关系。我们发现，图表用户的因果推断往往对样本大小不敏感，以至于它们偏离了我们的规范性基准。虽然交互式地在可视化中交叉过滤数据可以提高敏感性，但平均而言，用户在常见可视化中的表现并不比他们在文本列联表中的表现更可靠。这些实验证明了因果支持作为VA中推断评估框架的效用，并指出了使分析师在VA软件中的心理模型更加明确的机会。
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English: The MUonE experiment aims at providing a novel determination of the leading
hadronic contribution to the muon anomalous magnetic moment through the study
of elastic muon-electron scattering. Since the initial-state electrons are
bound in a low-$Z$ atomic target, the interaction between the incoming muons
and the nuclei is expected to be the main source of experimental background. In
this article, we study the production of a real lepton pair from the
muon-nucleus scattering, discussing its numerical impact in the MUonE kinematic
configuration. The process is described as a scattering of a muon in an
external Coulomb field with the addition of a form factor to describe the
nuclear charge distribution. The calculation is implemented in the fully
differential Monte Carlo event generator MESMER, without introducing any
approximation on the angular variables.
Chinese: MUonE实验旨在通过研究弹性μ子-电子散射，提供对μ子反常磁矩主导强子贡献的新确定。由于初始态电子被束缚在低$Z$原子靶中，预计入射μ子与核之间的相互作用将是实验背景的主要来源。在这篇文章中，我们研究了从μ子-核散射中产生真实电子对的产生过程，讨论了其在MUonE动力学配置中的数值影响。该过程被描述为μ子在外部库仑场中的散射，并添加了一个形式因子来描述核电荷分布。计算在完全微分蒙特卡洛事件生成器MESMER中实现，没有在角变量上引入任何近似。
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English: We demonstrate that partonic correlations that would traditionally be
identified as subleading on the basis of a generalized TMD-factorization
conjecture can become leading-power because of TMD-factorization breaking that
arises in hadron-hadron collisions with large transverse momentum back-to-back
hadrons produced in the final state. General forms of TMD-factorization fail
for such processes because of a previously noted incompatibility between the
requirements for TMD-factorization and the Ward identities of non-Abelian gauge
theories. We first review the basic steps for factorizing the gluon
distribution and then show that a conflict between TMD-factorization and the
non-Abelian Ward identity arises already at the level of a single extra soft or
collinear gluon when the partonic subprocess involves a TMD gluon distribution.
Next we show that the resulting TMD-factorization violating effects produce
leading-power final state spin asymmetries that would be classified as
subleading in a generalized TMD-factorization framework. We argue that similar
extra TMD-factorization breaking effects may be necessary to explain a range of
open phenomenological QCD puzzles. The potential to observe extra transverse
spin or azimuthal asymmetries in future experiments is highlighted as their
discovery may indicate an influence from novel and unexpected large distance
parton correlations.
Chinese: 我们展示了部分子关联，这些关联传统上被认为在基于广义TMD因子化猜想的子导级上，可以在有大量横动量反向对撞的末态产生的回对回质子中，由于TMD因子化破坏而成为主导级。一般形式的TMD因子化对于这样的过程不成立，因为此前注意到TMD因子化要求与非Abelian规范理论的Ward恒等式之间存在不兼容。我们首先回顾因子化胶子分布的基本步骤，然后展示当部分子过程涉及TMD胶子分布时，TMD因子化与非AbelianWard恒等式之间的冲突在单个额外的软或准直光子级别上已经出现。接下来，我们展示由此产生的TMD因子化违反效应会产生主导级末态自旋不对称性，这些效应在广义TMD因子化框架中被归类为子导级。我们认为，类似的额外的TMD因子化破坏效应可能也是解释一系列开放现象学QCD谜题所必需的。在未来的实验中可能观察到额外的横向自旋或方位不对称性，它们的发现可能表明有来自新颖和意外的长距离部分子关联的影响。
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English: A Hilbert space embedding for probability measures has recently been
proposed, wherein any probability measure is represented as a mean element in a
reproducing kernel Hilbert space (RKHS). Such an embedding has found
applications in homogeneity testing, independence testing, dimensionality
reduction, etc., with the requirement that the reproducing kernel is
characteristic, i.e., the embedding is injective.
In this paper, we generalize this embedding to finite signed Borel measures,
wherein any finite signed Borel measure is represented as a mean element in an
RKHS. We show that the proposed embedding is injective if and only if the
kernel is universal. This therefore, provides a novel characterization of
universal kernels, which are proposed in the context of achieving the Bayes
risk by kernel-based classification/regression algorithms. By exploiting this
relation between universality and the embedding of finite signed Borel measures
into an RKHS, we establish the relation between universal and characteristic
kernels.
Chinese: 最近提出了一种概率测度的希尔伯特空间嵌入方法，其中任何概率测度都被表示为一个再生核希尔伯特空间（RKHS）中的均值元素。此类嵌入已在同质性测试、独立性测试、降维等领域得到应用，其要求再生核具有特征性，即嵌入是单射的。
在本文中，我们将这种嵌入推广到有限有符号波雷测度，其中任何有限有符号波雷测度都被表示为一个RKHS中的均值元素。我们证明，所提出的嵌入是单射的当且仅当核是普遍的。因此，这为普遍核提供了一种新的表征方法，普遍核是在基于核的分类/回归算法实现贝叶斯风险的过程中提出的。通过利用普遍性与有限有符号波雷测度嵌入到RKHS之间的关系，我们建立了普遍核与特征性核之间的关系。
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English: We report here on a new heat treatment to prepare both dense polycrystalline
and single crystal MgB2 high quality samples in one single process. Resistivity
measurements for polycrystalline part of the sample gives a residual
resistivity ratio RRR=16.6 and a very low normal state resistivity rho(40K)=
0.28 microOhmcm. Both SEM and SQUID study on polycrystals reveal the high
quality, dense character and well coupling of grain boundaries. On the other
hand, the high quality single crystals have a unique shape that resembles the
hexagonal crystal structure. SQUID measurements reveals very weak flux pinning
character implying our single crystals to be very clean. In this study, we
conclude that heat treatment is playing a major rule on the characteristics of
both polycrystalline and single crystal MgB2. Samples are thoroughly
characterized by x-ray, resistivity, dc SQUID and SEM.
Chinese: 我们在此报告了一种新的热处理方法，该方法可以在一个单一过程中制备出致密的和多晶的MgB2以及单晶的高质量样品。对样品的多晶部分的电阻率测量给出了一个残留电阻率比RRR=16.6以及非常低的正常状态电阻率ρ(40K)=0.28微欧姆厘米。对多晶的SEM和SQUID研究揭示了高质量、致密的特性和良好的晶界耦合。另一方面，高质量的单晶具有独特的形状，类似于六方晶体结构。SQUID测量显示非常弱的通量钉扎特性，暗示我们的单晶非常纯净。在本研究中，我们得出结论，热处理对多晶和单晶MgB2的特性起着重要作用。样品通过X射线、电阻率、直流SQUID和SEM进行了彻底表征。
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English: Using the entire OPAL LEP1 on-peak Z hadronic decay sample, Z -> qbarq gamma
decays were selected by tagging hadronic final states with isolated photon
candidates in the electromagnetic calorimeter. Combining the measured rates of
Z -> qbarq gamma decays with the total rate of hadronic Z decays permits the
simultaneous determination of the widths of the Z into up- and down-type
quarks. The values obtained, with total errors, were Gamma u = 300 ^{+19}_{-18}
MeV and Gamma d = 381 ^{+12}_{-12} MeV. The results are in good agreement with
the Standard Model expectation.
Chinese: 使用整个OPAL LEP1高峰Z强子衰变样本，通过在电磁量能器中标记孤立光子候选者来选择Z -> qbarq gamma衰变。将测量的Z -> qbarq gamma衰变率与强子Z衰变的总率相结合，可以同时确定Z衰变到上型和下型夸克的宽度。获得的总误差值分别为Gamma u = 300 ^{+19}_{-18} MeV和Gamma d = 381 ^{+12}_{-12} MeV。结果与标准模型预期相符。
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English: In this note we study type II superstring theory on the direct product of
AdS3, the squashed three-sphere and a four-torus (AdS3 \times SqS3 \times T4).
We derive explicitly the Green-Schwarz action and discuss in detail the hidden
integrable structure corresponding to local and non-local currents. We find
that the model is classically integrable and that the currents generate a full
psu(1, 1|2) superalgebra, even though the corresponding spacetime isometries
are broken by the squashing.
Chinese: 在这篇笔记中，我们研究了AdS3、压缩的三球面和四环（AdS3 × SqS3 × T4）的直接积上的II型超弦理论。我们明确地推导了格林-斯瓦茨作用量，并详细讨论了对应于局部和非局部电流的隐藏可积结构。我们发现该模型在经典上是可积的，并且这些电流生成一个完整的psu(1, 1|2)超代数，尽管相应的时空等变度被压缩所破坏。
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English: Carbon is an essential element for the existence and evolution of life on
Earth. Its abundance in Earth's crust and mantle (the Bulk Silicate Earth, BSE)
is surprisingly high given that carbon is strongly siderophile (metal-loving)
at low pressures and temperatures, and hence should have segregated almost
completely into Earth's core during accretion. Estimates of the concentration
of carbon in the BSE lie in the range 100-260 ppm and are much higher than
expected based on simple models of core-mantle differentiation. Here we show
through experiments at the putative conditions of Earth's core formation (49-71
GPa and 3600-4000 K) that carbon is significantly less siderophile at these
conditions than at the low pressures ($\leq$13 GPa) and temperatures
($\leq$2500 K) of previous large volume press studies, but at least an order of
magnitude more siderophile than proposed recently based on an experimental
approach that is similar to ours. Using our new data along with previously
published results, we derive a new parameterization of the pressure-temperature
dependence of the metal-silicate partitioning of carbon. We apply this
parameterization in a model that combines planet formation and core-mantle
differentiation that is based on astrophysical N-body accretion simulations.
Because differentiated planetesimals were almost completely depleted in carbon
due to sublimation at high temperatures, almost all carbon in the BSE was added
by the accretion of fully-oxidized carbonaceous chondrite material from the
outer solar system. Carbon is added to the mantle continuously throughout
accretion and its concentration reaches values within the BSE range (e.g.
140$\pm$40 ppm) at the end of accretion. The corresponding final core and bulk
Earth carbon concentrations are 1270$\pm$300 ppm and 495$\pm$125 ppm
respectively.
Chinese: 碳是地球上生命存在和演化的基本元素。尽管在低压力和温度下碳具有很强的亲铁性（金属爱好者），因此应几乎完全分离到地球核心中，但碳在地壳和地幔（总体硅酸盐地球，BSE）中的丰度却出奇地高。BSE中碳的浓度估计在100-260 ppm之间，这比基于核-幔分异简单模型预期的浓度要高得多。在这里，我们通过在地球核心形成假想条件（49-71 GPa和3600-4000 K）下的实验表明，在这些条件下碳的亲铁性比之前在低压力（≤13 GPa）和温度（≤2500 K）下的大体积压实验研究中要低得多，但至少比最近基于与我们类似实验方法的提出要高一个数量级。利用我们的新数据以及之前发表的结果，我们推导出碳在金属-硅酸盐分配中的压力-温度依赖性的新参数化。我们将此参数化应用于一个结合行星形成和核-幔分异的模型，该模型基于天体物理N体吸积模拟。由于分异行星体因高温升华而几乎完全耗尽碳，因此BSE中的几乎所有碳都是通过从外太阳系吸积完全氧化的碳质球粒陨石材料而添加的。在整个吸积过程中，碳不断地添加到地幔中，其浓度在吸积结束时达到BSE范围内的值（例如140±40 ppm）。相应的最终核心和总体地球碳浓度分别为1270±300 ppm和495±125 ppm。
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English: We consider equivalent mechanical model of liquid sloshing in
partially-filled cylindrical vessel; the model treats both the regime of linear
sloshing, and strongly nonlinear sloshing regime. The latter is related to
hydraulic impacts applied to the vessel walls. These hydraulic impacts are
commonly simulated with the help of high-power potential and dissipation
functions. For the sake of analytic exploration, we substitute this traditional
approach by treatment of an idealized vibro-impact system with
velocity-dependent restitution coefficient. The obtained reduced model is
similar to recently explored system of linear primary oscillator with attached
vibro-impact energy sink. The ratio of modal mass of the first sloshing mode to
the total mass of the liquid and the tank serves as a natural small parameter
for multiple-scale analysis. In the case of external ground forcing,
steady-state responses and chaotic strongly modulated responses are revealed.
All analytical predictions of the reduced vibro-impact model are validated
against direct numerical simulations of initial equivalent model with
high-power smooth potential and dissipation functions, and good agreement is
observed.
Chinese: 我们考虑了一个部分充液圆柱形容器内液体晃动等效的力学模型；该模型既包括线性晃动的模式，也考虑了与容器壁接触的水力冲击相关的强非线性晃动模式。后者涉及对容器壁施加的水力冲击，这些水力冲击通常通过使用高功率势能和耗散函数来模拟。为了便于分析探索，我们用一个具有速度依赖的恢复系数的理想化振荡-冲击系统的处理方法取代了这一传统方法。得到的降阶模型与最近探索的线性主振荡器附加的振荡-冲击能量耗散器的系统类似。第一晃动模态的模态质量与液体和容器总质量的比值作为多尺度分析中的自然小参数。在外部地面激励的情况下，揭示了稳态响应和混沌强调制的响应。降阶振荡-冲击模型的所有分析预测都通过直接数值模拟初始等效模型与高功率光滑势能和耗散函数得到了验证，并且观察到了良好的一致性。
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English: The ability to map challenging subarctic environments opens new horizons for
robotic deployments in industries such as forestry, surveillance, and open-pit
mining. In this paper, we explore possibilities of large-scale lidar mapping in
a boreal forest. Computational and sensory requirements with regards to
contemporary hardware are considered as well. The lidar mapping is often based
on the SLAM technique relying on pose graph optimization, which fuses the
Iterative Closest Point (ICP) algorithm, Global Navigation Satellite System
(GNSS) positioning, and Inertial Measurement Unit (IMU) measurements. To handle
those sensors directly within the ICP minimization process, we propose an
alternative approach of embedding external constraints. Furthermore, a novel
formulation of a cost function is presented and cast into the problem of
handling uncertainties from GNSS and lidar points. To test our approach, we
acquired a large-scale dataset in the Foret Montmorency research forest. We
report on the technical problems faced during our winter deployments aiming at
building 3D maps using our new cost function. Those maps demonstrate both
global and local consistency over 4.1km.
Chinese: 能够对严峻的亚北极环境进行测绘，为林业、监控和露天采矿等行业的机器人部署开辟了新的前景。本文探讨了在北方森林中进行大规模激光雷达测绘的可能性。同时，我们也考虑了与当代硬件相关的计算和感知需求。激光雷达测绘通常基于SLAM技术，该技术依赖于姿态图优化，融合了迭代最近点（ICP）算法、全球导航卫星系统（GNSS）定位和惯性测量单元（IMU）测量。为了直接在ICP最小化过程中处理这些传感器，我们提出了一种嵌入外部约束的替代方法。此外，我们还提出了一种新的成本函数形式，并将其转化为处理GNSS和激光雷达点的不确定性的问题。为了测试我们的方法，我们在蒙特莫朗西研究森林中获取了一个大规模数据集。我们报告了在冬季部署过程中遇到的挑战，这些部署旨在使用我们新的成本函数构建3D地图。这些地图在4.1公里的区域内展示了全局和局部的连贯性。
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English: In the recent decade, it has been discovered that QKD systems are extremely
vulnerable to side-channel attacks. In particular, by exploiting the internal
working knowledge of practical detectors, it is possible to bring them to an
operating region whereby only certain target detectors are sensitive to
detections. Crucially, the adversary can use this loophole to learn everything
about the secret key without introducing any error to the quantum channel. In
this work, as a step towards overcoming detector blinding attacks, we focus on
an experimentally convenient countermeasure, where the efficiency of the
detectors is randomly varied.
Chinese: 在最近十年中，人们发现量子密钥分发（QKD）系统极易受到侧信道攻击。特别是，通过利用实际检测器的内部工作知识，可以将它们带入一个操作区域，在这个区域中，只有某些目标检测器对检测敏感。关键的是，攻击者可以利用这个漏洞了解关于密钥的所有信息，而不会向量子信道引入任何错误。在这项工作中，作为克服检测器盲化攻击的一步，我们关注了一种实验上方便的对策，即随机改变检测器的效率。
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English: The diffusion of iodine defects has been considered the most important
degradation mechanism of methylammonium lead iodine (MAPI) in solar cells. The
present study demonstrates the importance of the pressure inside this material
on the dynamics of iodine defects, using molecular dynamics simulations. It is
known that the diffusion coefficient of an iodine vacancy is an order of
magnitude higher than that of interstitial iodine. We show that this difference
systematically increases with increased tensile strain and that both diffusion
coefficients tend to zero when a compressive strain is applied. This result
suggests that compression of the MAPI can be a good solution to reduce its
degradation rate. %Also, different methods of determining the diffusion
coefficient, including mean squared displacement (MSD) and velocity
auto-correlation function, are discussed and applied to the case of ${\rm
V}_{\rm I}$. Besides, the statistical aspect of deriving the diffusion
coefficient from the mean squared displacement (MSD) is discussed in terms of
the initial conditions (positions and velocities) of the atoms and the
simulation time, considering different seeds of the pseudo-random number
generator used in the simulations performed with the LAMMPS software.
Chinese: 碘缺陷的扩散被认为是太阳能电池中甲基铵铅碘（MAPI）降解的最重要机制。本研究通过分子动力学模拟证明了该材料内部压力对碘缺陷动力学的重要性。已知碘空位的扩散系数比间隙碘的扩散系数高一个数量级。我们表明，这种差异随着拉伸应力的增加而系统地增加，并且当施加压缩应力时，两个扩散系数都趋于零。这一结果表明，压缩MAPI可以是一种减少其降解速率的好方法。此外，还讨论并应用了确定扩散系数的不同方法，包括平均平方位移（MSD）和速度自相关函数，这些方法被用于${\rm V}_{\rm I}$的情况。此外，还讨论了从平均平方位移（MSD）推导扩散系数的统计方面，这涉及到原子（位置和速度）的初始条件以及模拟时间，考虑到在LAMMPS软件进行的模拟中使用的伪随机数生成器的不同种子。
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English: We study the generation of superpositions of N00N states by overlapping
few-photon-subtracted squeezed vacuum states and coherent states on a 50/50
beam splitter. Assuming parameters that are feasible with current technology
results in output states with mean photon numbers of several tens. We show that
the generated quantum states violate local realism even in the presence of
considerable loss. The occurrence of strong quantum correlations for mesoscopic
quantum states of light is particularly beneficial for coupling light and
matter quantum systems.
Chinese: 我们研究通过在50/50分束器上重叠少量光子减去的压缩真空态和相干态来生成N00N态的叠加。假设的参数与当前技术可行，导致输出态的平均光子数达到几十个。我们表明，生成的量子态即使在存在相当大的损耗的情况下也违反了局域实在论。对于光的中观量子态的强量子相关性特别有利于耦合光和物质量子系统。
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English: We study the influence of the isospin asymmetry on the phase structure of
strongly interacting quark matter near the critical point (CP) using a
Ginzburg-Landau approach. The effect is found to be drastic, not only bringing
about the shift of the location of the CP, but resulting in a rich phase
structure in the vicinity of the CP. In particular, new tricritical and triple
points emerge as soon as the isospin density becomes finite. Moreover, we find
the CP being washed out from the phase diagram due to the stabilization of a
homogeneous charged pion condensate when the isospin chemical potential exceeds
a critical value. We derive a model-independent universal relation between the
critical isospin chemical potential and the chiral condensate at the CP. We
also study the effect of the $\mathrm{U}(1)_\mathrm{A}$ anomaly on the phase
transition to the pion condensate in the vicinity of chiral crossover.
Chinese: 我们使用Ginzburg-Landau方法研究同位旋不对称性对临界点（CP）附近强相互作用夸克物质相结构的影響。研究发现，这种影响是显著的，不仅导致了CP位置的偏移，而且在CP附近产生了丰富的相结构。特别是，当同位旋密度变得有限时，新的三重临界点和三重点立即出现。此外，我们发现当同位旋化学势超过临界值时，由于均匀带电π介子凝聚态的稳定，CP从相图中消失。我们推导出一个与模型无关的普适关系，该关系描述了临界同位旋化学势与CP处的手征凝聚态之间的关系。我们还研究了$\mathrm{U}(1)_\mathrm{A}$异常对接近手征交叉过渡相变到π介子凝聚态的影响。
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English: The raw coronagraphic performance of current high-contrast imaging
instruments is limited by the presence of a quasi-static speckle (QSS)
background, resulting from instrumental non-common path errors (NCPEs). Rapid
development of efficient speckle subtraction techniques in data reduction has
enabled final contrasts of up to 10-6 to be obtained, however it remains
preferable to eliminate the underlying NCPEs at the source. In this work we
introduce the coronagraphic Modal Wavefront Sensor (cMWS), a new wavefront
sensor suitable for real-time NCPE correction. This pupil-plane optic combines
the apodizing phase plate coronagraph with a holographic modal wavefront
sensor, to provide simultaneous coronagraphic imaging and focal-plane wavefront
sensing using the science point spread function. We first characterise the
baseline performance of the cMWS via idealised closed-loop simulations, showing
that the sensor successfully recovers diffraction-limited coronagraph
performance over an effective dynamic range of +/-2.5 radians root-mean-square
(RMS) wavefront error within 2-10 iterations. We then present the results of
initial on-sky testing at the William Herschel Telescope, and demonstrate that
the sensor is able to retrieve injected wavefront aberrations to an accuracy of
10nm RMS under realistic seeing conditions. We also find that the cMWS is
capable of real-time broadband measurement of atmospheric wavefront variance at
a cadence of 50Hz across an uncorrected telescope sub-aperture. When combined
with a suitable closed-loop adaptive optics system, the cMWS holds the
potential to deliver an improvement in raw contrast of up to two orders of
magnitude over the uncorrected QSS floor. Such a sensor would be eminently
suitable for the direct imaging and spectroscopy of exoplanets with both
existing and future instruments, including EPICS and METIS for the E-ELT.
Chinese: 当前高对比度成像仪的原始光栅性能受到准静态斑纹（QSS）背景的限制，这种背景是由仪器非共光路误差（NCPEs）引起的。数据降采样中高效斑纹减除技术的快速发展使得最终对比度达到了10-6，然而，在源头消除潜在的NCPEs仍然是更可取的。在这项工作中，我们引入了光栅模式波前传感器（cMWS），这是一种适合实时NCPE校正的新波前传感器。该瞳孔平面光学元件结合了消光相位板光栅和全息模式波前传感器，以使用科学点扩展函数同时提供光栅成像和焦平面波前传感。我们首先通过理想化的闭环模拟来表征cMWS的基线性能，显示该传感器在2-10次迭代内成功恢复到有效动态范围±2.5弧度均方根（RMS）波前误差的衍射极限光栅性能。然后，我们展示了在威廉·赫歇尔望远镜上的初步天文测试结果，并证明该传感器能够在实际视宁度条件下以10nm RMS的精度检索注入的波前像差。我们还发现，cMWS能够在50Hz的采样率下实时测量未经校正的望远镜子孔径的大气波前方差。当与合适的闭环自适应光学系统结合时，cMWS有望将原始对比度提高两个数量级，超过未经校正的QSS地板。这样的传感器非常适合使用现有和未来的仪器直接成像和光谱分析系外行星，包括EPICS和METIS等E-ELT仪器。
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English: The innovation provided by network virtualization in 5G, together with
standardization and openness boosted by the Open Radio Access Network (O-RAN)
Alliance, has paved the way to a collaborative future in cellular systems,
driven by flexible network sharing. Such advents are expected to attract new
players like content providers and verticals, increasing competitiveness in the
telecom market. However, scalability and trust issues are expected to arise,
given the criticality of ownership traceability and resource exchanging in a
sharing ecosystem. To address that, we propose integrating blockchain
technology for enabling mobile operators and other players to exchange RAN
resources (e.g., infrastructure) in the form of virtual network functions (VNF)
autonomously and dynamically. Blockchain will provide automation, robustness,
trustworthiness, and reliability to mobile networks, thus bringing confidence
to open RAN environments. In particular, we define a novel O-RAN-based
blockchain-enabled architecture that allows automating RAN sharing procedures
through either auction or marketplace-based mechanisms. The potential
advantages of the proposed solution are demonstrated through simulation
results. The used simulation platform is openly released.
Chinese: 5G网络虚拟化带来的创新，以及由开放无线接入网络（O-RAN）联盟推动的标准化和开放性，为基于灵活网络共享的蜂窝系统协作未来铺平了道路。此类新技术的出现预计将吸引内容提供商和垂直行业等新参与者，增强电信市场的竞争力。然而，鉴于共享生态系统中所有权可追溯性和资源交换的关键性，可扩展性和信任问题预计将会出现。为了解决这个问题，我们提出集成区块链技术，使移动运营商和其他参与者能够以虚拟网络功能（VNF）的形式自主和动态地交换RAN资源（例如基础设施）。区块链将为移动网络提供自动化、鲁棒性、可信度和可靠性，从而为开放RAN环境带来信心。特别是，我们定义了一种基于O-RAN的区块链赋能架构，该架构允许通过拍卖或基于市场的机制自动化RAN共享流程。所提出的解决方案的潜在优势通过仿真结果得到了验证。使用的仿真平台已公开发布。
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English: The results reported by Gambini, Pullin and Rastgoo in (2010 Class. Quantum
Grav. 27 025002) are special cases of a general treatment of canonical
variables for dilaton gravity models published in (2009 Class. Quantum Grav. 26
035018).
Chinese: 由Gambini、Pullin和Rastgoo在(2010 Class. Quantum Grav. 27 025002)报道的结果，是发表于(2009 Class. Quantum Grav. 26 035018)的稀释引力模型正则变量一般处理中的特例。
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English: The conventional linear polarizer only allows the electric component parallel
to the polarizer axis to pass through whereas prohibits the vertical component.
We propose that a specially-designed single-layer plasmonic polarizer can
couple both parallel and vertical electric components to the transmission, thus
breaking the classical law of Malus. A variety of anomalous polarization
effects, such as the asymmetric polarization-angle dependence, enhanced
polarization filtering with wide polarization angle, and tunable polarization
rotation from 0o to 90o, can be resulted. To understand the effects, the
generalized law of Malus,originating from the superposition principle, has been
presented and analyzed. This provides a basis for studying the
interference-type plasmonic polarizers, where the interference effect and
polarization effect are combined together. The difference between the plasmonic
and conventional polarizers is of both fundamental and practical interests.
Chinese: 传统的线性偏振器仅允许平行于偏振器轴的电分量通过，而禁止垂直分量通过。我们提出一种特别设计的单层等离子体偏振器能够将平行和垂直的电分量都耦合到传输中，从而打破了马吕斯定律的经典法则。可以产生一系列异常偏振效应，例如偏振角依赖的非对称性、宽偏振角度增强的偏振滤波以及从0°到90°可调偏振旋转，等等。为了理解这些效应，基于叠加原理提出了马吕斯定律的广义形式，并对其进行了分析。这为研究干涉型等离子体偏振器提供了基础，其中干涉效应和偏振效应被结合在一起。等离子体偏振器和传统偏振器之间的差异在理论和实践中都具有重要意义。
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English: Supermassive black holes (SMBHs) reside at the center of every massive galaxy
in the local Universe with masses that closely correlate with observations of
their host galaxy implying a connected evolutionary history. The population of
binary SMBHs, which form following galaxy mergers, is expected to produce a
gravitational wave background (GWB) detectable by pulsar timing arrays (PTAs).
PTAs are starting to see hints of what may be a GWB, and the amplitude of the
emerging signal is towards the higher end of model predictions. Simulated
populations of binary SMBHs can be constructed from observations of galaxies
and are used to make predictions about the nature of the GWB. The greatest
source of uncertainty in these observation-based models comes from the
inference of the SMBH mass function, which is derived from observed host galaxy
properties. In this paper, I undertake a new approach for inferring the SMBH
mass function starting from a velocity dispersion function rather than a galaxy
stellar mass function. I argue that this method allows for a more direct
inference by relying on a larger suite of individual galaxy observations as
well as relying on a more "fundamental" SMBH mass relation. I find that the
resulting binary SMBH population contains more massive systems at higher
redshifts than previous models. Additionally, I explore the implications for
the detection of individually resolvable sources in PTA data.
Chinese: 超大质量黑洞（SMBHs）存在于本星系团中每个大型星系的中心，其质量与宿主星系的观测结果密切相关，暗示着一种相互关联的演化历史。通过星系合并形成的双星超大质量黑洞群体预计会产生可被脉冲星计时阵列（PTAs）探测到的引力波背景（GWB）。PTAs开始观测到可能存在的GWB迹象，且当前出现的信号振幅处于模型预测的高值范围。通过观测星系构建的双星超大质量黑洞模拟群体可用于预测GWB的性质。这些基于观测的模型中最大的不确定性来源在于超大质量黑洞质量函数的推断，该函数基于观测到的宿主星系属性推导。本文提出了一种新的推断超大质量黑洞质量函数的方法，该方法从速度弥散函数而非星系恒星质量函数出发。我主张这种方法能够通过依赖更大规模的单个星系观测以及更“基本”的超大质量黑洞质量关系来实现更直接的推断。我发现，由此产生的双星超大质量黑洞群体在更高红移处包含更致密的系统，这与之前的模型不同。此外，我还探讨了PTA数据中可分辨单个源的探测所产生的影响。
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English: We study a stochastic differential game in a ruin theoretic environment. In
our setting two insurers compete for market share, which is represented by a
joint performance functional. Consequently, one of the insurers strives to
maximize it, while the other seeks to minimize it. As a modelling basis we use
classical surplus processes extended by dynamic reinsurance opportunities,
which allows us to use techniques from the theory of piecewise deterministic
Markov processes to analyze the resulting game. In this context we show that a
dynamic programming principle for the upper and lower value of the game holds
true and that these values are unique viscosity solutions to the associated
Bellman-Isaacs equations. Finally, we provide some numerical illustrations.
Chinese: 我们研究了一个在破产理论环境下的随机微分博弈。在我们的设定中，两家保险公司为了市场份额而竞争，市场份额由一个联合性能泛函表示。因此，一家保险公司努力最大化它，而另一家则寻求最小化它。作为建模的基础，我们使用了扩展了动态再保险机会的经典盈余过程，这使得我们可以使用分段确定性马尔可夫过程理论的技术来分析产生的博弈。在这种情况下，我们证明了博弈的上值和下值动态规划原理是成立的，并且这些值是相关Bellman-Isaacs方程的唯一粘性解。最后，我们提供了一些数值示例。
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English: Deep learning based fusion methods have been achieving promising performance
in image fusion tasks. This is attributed to the network architecture that
plays a very important role in the fusion process. However, in general, it is
hard to specify a good fusion architecture, and consequently, the design of
fusion networks is still a black art, rather than science. To address this
problem, we formulate the fusion task mathematically, and establish a
connection between its optimal solution and the network architecture that can
implement it. This approach leads to a novel method proposed in the paper of
constructing a lightweight fusion network. It avoids the time-consuming
empirical network design by a trial-and-test strategy. In particular we adopt a
learnable representation approach to the fusion task, in which the construction
of the fusion network architecture is guided by the optimisation algorithm
producing the learnable model. The low-rank representation (LRR) objective is
the foundation of our learnable model. The matrix multiplications, which are at
the heart of the solution are transformed into convolutional operations, and
the iterative process of optimisation is replaced by a special feed-forward
network. Based on this novel network architecture, an end-to-end lightweight
fusion network is constructed to fuse infrared and visible light images. Its
successful training is facilitated by a detail-to-semantic information loss
function proposed to preserve the image details and to enhance the salient
features of the source images. Our experiments show that the proposed fusion
network exhibits better fusion performance than the state-of-the-art fusion
methods on public datasets. Interestingly, our network requires a fewer
training parameters than other existing methods. The codes are available at
https://github.com/hli1221/imagefusion-LRRNet
Chinese: 基于深度学习的融合方法在图像融合任务上已取得显著成效。这主要归因于在融合过程中起关键作用的架构设计。然而，通常来说，指定一个良好的融合架构是一个挑战，因此融合网络的构建仍是一门艺术，而非科学。为了解决这个问题，我们通过数学方法来建模融合任务，并建立了其最优解与能够实现它的网络架构之间的联系。这种方法引领我们在论文中提出了一种构建轻量级融合网络的新方法。它避免了通过试验和错误策略进行耗时的经验网络设计。特别地，我们采用了针对融合任务的可学习表示方法，其中融合网络架构的构建由优化算法产生的可学习模型引导。低秩表示（LRR）目标函数是我们可学习模型的基础。矩阵乘法，作为解决方案的核心，被转化为卷积操作，而优化算法的迭代过程被替换为一种特殊的前馈网络。基于这种新颖的网络架构，我们构建了一个端到端的轻量级融合网络，用于融合红外和可见光图像。一个细节到语义信息损失函数被提出，该函数有助于促进网络的训练，该函数旨在保留图像细节并增强源图像的显著特征。我们的实验表明，提出的融合网络在公共数据集上比最先进的融合方法表现更好。有趣的是，我们的网络需要的训练参数比其他现有方法更少。代码可从https://github.com/hli1221/imagefusion-LRRNet获取。
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English: We report on two X-ray observations of the transient source XTE J0421+560
performed by BeppoSAX, and on a series of observations performed by the 0.7m
Teramo-Normale Telescope. Outburst peak occurrence time and duration depend on
photon energy: the outburst peak is achieved first in the X-ray band, then in
the optical and finally in the radio. An exponential decay law fits well the
X-ray data except in the TOO2 0.5-1.0 keV band, where erratic time variability
is detected. During TOO1 the e-folding time scale decreases with energy up to ~
20 keV, when it achieves a saturation; during TOO2 it decreases up to ~ 2 keV
and then increases. This change is correlated with a spectral change,
characterized by the onset of a soft (< 2 keV) component in TOO2 (Orr et al.
1998). This component might originate from the relativistic jets, while the
hard component is more likely associated to processes occurring in the
circumstellar matter and/or near the compact object. Optical observations show
that the object appears intrinsically red even during the outburst. The nature
of the compact object is discussed.
Chinese: 我们报告了由BeppoSAX进行的两次X射线观测，以及由0.7米特拉莫-诺尔马望远镜进行的一系列观测。爆发峰值出现时间和持续时间依赖于光子能量：爆发峰值首先在X射线波段实现，然后在光学波段，最后在射电波段。除了TOO2 0.5-1.0 keV波段，X射线数据很好地拟合指数衰减定律，检测到时间变异性不规则。在TOO1中，指数衰减时间尺度随能量增加至约20 keV，之后达到饱和；在TOO2中，指数衰减时间尺度降至约2 keV然后增加。这种变化与光谱变化相关，特征是TOO2中出现一个较软的（<2 keV）成分（Orr等人，1998年）。这个成分可能来源于相对论喷流，而较硬的成分更可能与发生在周围星周物质和/或紧致物体附近的物理过程有关。光学观测表明，即使在爆发期间，目标也呈现出内在的红色。紧致物体的性质进行了讨论。
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English: In this work, we present a generalization to varieties and sheaves of the
fundamental ideal of the Witt ring of a field by defining a sheaf of
fundamental ideals $\tilde{I}$ and a sheaf of Witt rings $\tilde{W}$ in the
obvious way. The Milnor conjecture then relates the associated graded of
$\tilde{W}$ to Milnor K-theory and so allows the classical invariants of a
bilinear space over a field to be extended to our setting using \'etale
cohomology. As an application of these results, we calculate the Witt ring of a
smooth curve with good reduction over a non-dyadic local field.
Chinese: 在这项工作中，我们通过定义一个基本理想的层 $\tilde{I}$ 和一个Witt环的层 $\tilde{W}$，以明显的方式将域的Witt环的基本理想推广到簇和层上。随后，米尔诺猜想将 $\tilde{W}$ 的关联梯度与米尔诺K理论联系起来，从而允许利用概形上同调将域上双线性空间的传统不变量扩展到我们的设置中。作为这些结果的应用，我们计算了在非二进制局部域上具有良约化性质的平滑曲线的Witt环。
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English: Objective: To examine the moderation effects of hormonal factors on the
associations between vascular risk factors and white matter hyperintensities
(WMH) in men and women, separately. Methods: WMH were automatically segmented
and quantified in the UK Biobank dataset (N = 18,294). Generalised linear
models were applied to examine 1) the main effects of vascular (body mass
index, hip to waist ratio, pulse wave velocity, hypercholesterolemia, diabetes,
hypertension, smoking status) and hormonal (testosterone levels, contraceptive
pill, hormone replacement therapy, menopause) factors on WMH, and 2) the
moderation effects of hormonal factors on the relationship between vascular
risk factors and WMH volumes. Results: In men with testosterone levels one
standard deviation (SD) higher than the mean value, increased body mass index
and pulse wave velocity, and smoking were associated with higher WMH volumes.
The association between body mass index and WMH was more significant in the
periventricular white matter regions, whilst the relationship between pulse
wave velocity and WMH was restricted to deep white matter regions. Men with low
testosterone levels (one SD below the mean level) showed a significant
association between hypercholesterolemia and higher deep WMH volumes.
Hypertensive women showed higher WMH volumes than women without hypertension
regardless of whether hormone replacement therapy was used. However, higher WMH
volumes, especially in the deep white matter regions, were found in women who
did not use hormone replacement therapy or use it for a shorter duration.
Conclusion: These findings highlighted the importance of considering hormonal
risk factors in the prevention and management of WMH.
Chinese: 目标：分别检查激素因素对血管风险因素与白质高信号（WMH）之间关联的调节作用。方法：在英国生物样本库数据集中（N = 18,294），自动分割和量化了WMH。应用广义线性模型来检验1）血管（体重指数、臀围与腰围比、脉搏波速度、高胆固醇血症、糖尿病、高血压、吸烟状况）和激素（睾酮水平、避孕药、激素替代疗法、更年期）因素对WMH的主要影响，以及2）激素因素对血管风险因素与WMH体积之间关系的调节作用。结果：在睾酮水平比平均值高一个标准差（SD）的男性中，增加的体重指数、脉搏波速度和吸烟与更高的WMH体积相关。体重指数与WMH之间的关联在脑室周围白质区域更为显著，而脉搏波速度与WMH之间的关系仅限于深层白质区域。睾酮水平低（低于平均值一个SD）的男性显示出高胆固醇血症与更高的深层WMH体积之间的显著关联。无论是否使用激素替代疗法，高血压女性的WMH体积都高于无高血压的女性。然而，在未使用激素替代疗法或使用时间较短的妇女中，尤其是在深层白质区域，WMH体积更高。结论：这些发现强调了在预防和治疗WMH时考虑激素风险因素的重要性。
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English: The primary issue in inverse halftoning is removing noisy dots on flat areas
and restoring image structures (e.g., lines, patterns) on textured areas.
Hence, a new structure-aware deep convolutional neural network that
incorporates two subnetworks is proposed in this paper. One subnetwork is for
image structure prediction while the other is for continuous-tone image
reconstruction. First, to predict image structures, patch pairs comprising
continuous-tone patches and the corresponding halftoned patches generated
through digital halftoning are trained. Subsequently, gradient patches are
generated by convolving gradient filters with the continuous-tone patches. The
subnetwork for the image structure prediction is trained using the mini-batch
gradient descent algorithm given the halftoned patches and gradient patches,
which are fed into the input and loss layers of the subnetwork, respectively.
Next, the predicted map including the image structures is stacked on the top of
the input halftoned image through a fusion layer and fed into the image
reconstruction subnetwork such that the entire network is trained adaptively to
the image structures. The experimental results confirm that the proposed
structure-aware network can remove noisy dot-patterns well on flat areas and
restore details clearly on textured areas. Furthermore, it is demonstrated that
the proposed method surpasses the conventional state-of-the-art methods based
on deep convolutional neural networks and locally learned dictionaries.
Chinese: 逆调色中的主要问题是去除平坦区域的噪点，并在纹理区域恢复图像结构（例如线条、图案）。因此，本文提出了一种结合两个子网络的结构感知深度卷积神经网络。一个子网络用于图像结构预测，另一个用于连续色调图像重建。首先，通过训练包含连续色调块和通过数字调色生成的相应调色块的块对来预测图像结构。随后，通过将梯度滤波器与连续色调块卷积来生成梯度块。给定调色块和梯度块，使用小批量梯度下降算法训练图像结构预测子网络，其中调色块和梯度块分别输入到子网络的输入层和损失层。接下来，包含图像结构的预测图通过融合层堆叠在输入调色图像的顶部，并输入到图像重建子网络，使整个网络能够自适应于图像结构进行训练。实验结果证实，所提出的结构感知网络能够在平坦区域很好地去除噪点图案，并在纹理区域清晰地恢复细节。此外，实验表明，所提出的方法超越了基于深度卷积神经网络和局部学习字典的传统最先进方法。
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English: The physics of interacting quantum wires has attracted a lot of attention
recently. When the density of electrons in the wire is very low, the strong
repulsion between electrons leads to the formation of a Wigner crystal. We
review the rich spin and orbital properties of the Wigner crystal, both in the
one-dimensional and quasi-one-dimensional regime. In the one-dimensional Wigner
crystal the electron spins form an antiferromagnetic Heisenberg chain with
exponentially small exchange coupling. In the presence of leads the resulting
inhomogeneity of the electron density causes a violation of spin-charge
separation. As a consequence the spin degrees of freedom affect the conductance
of the wire. Upon increasing the electron density, the Wigner crystal starts
deviating from the strictly one-dimensional geometry, forming a zigzag
structure instead. Spin interactions in this regime are dominated by ring
exchanges, and the phase diagram of the resulting zigzag spin chain has a
number of unpolarized phases as well as regions of complete and partial spin
polarization. Finally we address the orbital properties in the vicinity of the
transition from a one-dimensional to a quasi-one-dimensional state. Due to the
locking between chains in the zigzag Wigner crystal, only one gapless mode
exists. Manifestations of Wigner crystal physics at weak interactions are
explored by studying the fate of the additional gapped low-energy mode as a
function of interaction strength.
Chinese: 相互作用量子线的物理性质近来引起了广泛关注。当线中的电子密度非常低时，电子之间的强排斥力会导致维格纳晶体的形成。我们回顾了维格纳晶体在一维和准一维体系中的丰富自旋和轨道性质。在一维维格纳晶体中，电子自旋形成具有指数小交换耦合的反铁磁海森堡链。在存在引线的情况下，电子密度的不均匀性导致自旋-电荷分离的破坏。因此，自旋自由度会影响线的电导率。随着电子密度的增加，维格纳晶体开始偏离严格的一维几何结构，转而形成之字形结构。在此体系中，自旋相互作用主要由环交换主导，所得之字形自旋链的相图包含多个无极化相以及完全和部分自旋极化的区域。最后，我们讨论了从一维状态向准一维状态转变附近的轨道性质。由于之字形维格纳晶体中链之间的锁定，仅存在一个无隙模式。通过研究附加的带隙低能模式随相互作用强度的变化，探索了弱相互作用下维格纳晶体物理现象的表现。
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English: We study the pure and thermal states of quantized scalar and tensor
perturbations in various epochs of Universe evolution. We calculate the density
matrix of non-relativistic particles in an environment of these perturbations.
We show that particle's motion can be described by a stochastic equation with a
noise coming from the cosmological environment. We investigate the squeezing of
Gaussian wave packets in different epochs and its impact upon the noise of
quantized cosmological perturbations.
Chinese: 我们研究宇宙演化各个时期中量子标量和张量扰动的纯态和热态。我们计算了这些扰动环境中的非相对论粒子的密度矩阵。我们表明，粒子的运动可以用一个随机方程来描述，其噪声来自宇宙环境。我们研究了不同时期高斯波包的压缩及其对量子宇宙扰动噪声的影响。
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