近距离感染传播的蒙特卡罗模拟研究 | 网络科学论文速递39篇-集智俱乐部

本文由机器翻译,仅供参考,感兴趣请查阅论文原文

核心速递



  • 近距离感染传播的蒙特卡罗模拟研究;

  • 高效运输物流---- 奥地利城市货运的一种途径;

  • 使用变化中的变化模型,在选定的欧洲国家和美国,国家封锁对新型冠状病毒肺炎死亡的影响;

  • 监测政府干预以遏制新型冠状病毒肺炎的影响: 一个定量的方法;

  • 集群内和集群间耦合平衡对非线性网络系统性能的影响;

  • 美国、亚洲和欧洲新型冠状病毒肺炎流行的时间数据系列表明,SARS-CoV-2 Spike D614G 变异具有选择性;

  • 墨西哥的新型冠状病毒肺炎: 流行病网络;

  • 数据驱动的分析: 封锁是否遏制了新型冠状病毒肺炎在印度的传播;

  • 森林砍伐与世界人口可持续性: 定量分析;

  • 时间依赖和时间独立的 SIR 模型应用于在阿根廷、巴西、哥伦比亚、墨西哥和南非爆发的新型冠状病毒肺炎;

  • 通风减少病毒传播的必要性简单量化;

  •  Lévy 漫步超扩散开始的普遍性起源;

  • 三维湍流中速度环流的概率分布;

  • 驱动谐振子的动力学耦合了随机场中成对相互作用的伊辛自旋;

  • 基于光学偶极力阱释放和捕获的空气微粒快速质量测定技术;

  • 滑动分析中的半柔性聚合物: 凹入转变,转换和活性的作用;

  • 异常的血小板运输和脂肪尾分布;

  • 基于两国链接追踪抽样的跨国社会领域测量;

  • 隐性众包识别在线社交网络中的滥用行为;

  • 在黑暗网络中挖掘用户交互模式来预测企业网络事件;

  • 用于检索流量 Tweets 的自动查询优化;

  • 利用图形神经网络学习传染源的研究;

  • (非)稳定网络的 Nash 均衡;

  • 澳大利亚新型冠状病毒肺炎流行引起的社区情绪动态研究;

  • 考虑私有节点的随机漫步社会网络性质估计;

  • 亚洲国家的风险沟通: 新型冠状病毒肺炎在 Twitter 上的演讲;

  • 当社会影响力促进群体智慧时当社会影响力促进群体智慧时;

  • 实验耦合 logistic 映射中的分岔和滞后现象;

  • 在网络化动态系统中识别有助于产生极端事件的边界;

  • 进化油藏计算网络中的功能差异;

  • 社会信任网络中的意见最大化;

  • 监测新型冠状病毒肺炎流感大流行下的全球情绪;

  • 基于资源分配的超边界预测;

  • 青少年幸福感测量: 幼稚数字痕迹与调查数据的对应;

  • 自适应扩散下的多观测谣言源检测;

  • 心理物理学: 两个耦合的正方形脉冲神经元在临界状态下具有巨大的动态范围;

  • 英国新型冠状病毒肺炎禁闭: 对空气污染有什么影响;

  • 几何,推理,复杂性和民主;

  • 使用概率细胞自动机研究计算模型新型冠状病毒肺炎流行病;





近距离感染传播的蒙特卡罗模拟研究


原文标题:

A Monte Carlo simulation study of proximity-based infection spread

地址:

http://arxiv.org/abs/2006.12212

作者:

S. Triambak,D. P. Mahapatra


Abstract:Recent work showed that the initial COVID-19 data from China followed a subexponential power-law increase in the number of confirmed cases. This was attributed to a combination of effective containment and mitigation measures employed as well as behaviorial changes by the population. In view of this, we performed a Monte Carlo random walk study to better understand proximity-based infectious disease spread, particularly under restrictions. Our model is found to be rather robust and reproduces the observed power-law growth without relying on any external parameters. Three growth regimes (quadratic, power-law and exponential) emerge naturally from our simulations. These results suggest that the early containment of the disease within China was close to optimal and could not have been significantly improved upon. We show that reasonable agreement with other data can be attained by incorporating small-world-like connections in the simulations. The prescribed model and its generalizations might be useful for future strategies in the midst of the present pandemic.

摘要:最近的研究表明,来自中国的新型冠状病毒肺炎卫生组织的初始数据显示,确诊病例的数量呈次指数幂律增长。这是由于采取了有效的遏制和缓解措施,以及人口的行为变化。有鉴于此,我们进行了蒙特卡洛随机漫步研究,以更好地理解基于邻近的传染病扩散,特别是在限制条件下。我们的模型是相当稳健的,并重现了观察到的幂律增长而不依赖于任何外部参数。三种增长机制(二次型、幂律型和指数型)从我们的模拟中自然产生。这些结果表明,在中国早期遏制该病是接近最佳的,不可能有显着改善。我们表明,合理的协议与其他数据可以通过纳入小世界类似的连接模拟。这一规定的模式及其概括可能有助于在当前大流行期间制定今后的战略。



高效运输物流---- 奥地利

城市货运的一种途径


原文标题:

Efficient Transport Logistics, An Approach for Urban Freight Transport in Austria

地址:

http://arxiv.org/abs/2006.11377

作者:

Verena Brandstätter,Cristina Olaverri-Monreal


Abstract:To alleviate traffic congestion that results from the growth of e-commerce we propose an approach in the city of Linz, Austria by relying on shared distribution centers from different companies. We develop two algorithms to find out the optimal location for the hubs and calculate the shortest path between locations. Results showed that in an urban environment, the implementation of hubs results in a reduction of the number of delivery vehicles. It reduces driving distances from hub to the customers, and also benefits the drivers that need to return home every day.

摘要:为了减轻电子商务增长带来的交通堵塞,我们提出了一种在奥地利林茨市通过依赖于不同公司的共享配送中心的方法。我们发展了两个算法来找出枢纽的最佳位置和计算位置之间的最短路径。结果表明,在城市环境中,建立枢纽导致运输车辆数量减少。它缩短了从枢纽到客户的行车距离,也使每天需要回家的司机受益。



使用变化中的变化模型,

在选定的欧洲国家和美国,

国家封锁对新型冠状

病毒肺炎死亡的影响

原文标题:

Impact of national lockdown on COVID-19 deaths in select European countries and the US using a Changes-in-Changes model

地址:

http://arxiv.org/abs/2006.12251

作者:

Mudit Kapoor,Shamika Ravi


Abstract:In this paper, we estimate the impact of national lockdown on COVID-19 related total and daily deaths, per million people, in select European countries. In particular, we compare countries that imposed a nationwide lockdown (Treatment group); Belgium, Denmark, France, Germany, Italy, Norway, Spain, United Kingdom (UK), and the US, to Sweden (Control group) that did not impose national lockdown using a changes-in-changes (CIC) estimation model. The key advantage of the CIC model as compared to the standard difference-in-difference model is that CIC allows for mean and variance of the outcomes to change over time in the absence of any policy intervention, and CIC accounts for endogeneity in the choice of policy intervention. Our results indicate that in contrast to Sweden, which did not impose a national lockdown, Germany, and to some extent, the US were the two countries where nationwide lockdown had a significant impact on the reduction in COVID-19 related total and daily deaths per million people. In Norway and Denmark, there was no significant impact on total and daily deaths per million people relative to Sweden. Whereas in other countries; Belgium, France, Italy, Spain, and the UK, the effect of the lockdown was in the opposite direction, that is, they experienced significantly higher COVID-19 related total and daily deaths per million people, post the lockdown as compared to Sweden. Our results suggest that the impact of nationwide lockdown on COVID-19 related total and daily deaths per million people varied from one country to another.

摘要:在这篇论文中,我们估计了国家防范禁闭对欧洲某些国家每天每百万人中与新型冠状病毒肺炎有关的总死亡人数和每日死亡人数的影响。特别是,我们将实施全国防范禁闭的国家(治疗小组)、比利时、丹麦、法国、德国、意大利、挪威、西班牙、英国(英国)和美国与瑞典(控制小组)进行了比较,瑞典没有使用变更估计模型(CIC)实施全国防范禁闭。与标准差异模型相比,CIC 模型的主要优势在于,在没有任何政策干预的情况下,CIC 允许结果的均值和方差随时间而变化,CIC 解释了政策干预选择的内生性。我们的研究结果表明,与没有实施全国防范禁闭的瑞典相比,德国和在某种程度上,美国是全国防范禁闭对减少与新型冠状病毒肺炎有关的总死亡人数和每天每百万人死亡人数有显著影响的两个国家。在挪威和丹麦,与瑞典相比,每百万人的总死亡率和每日死亡率没有显著影响。然而在其他国家,比利时,法国,意大利,西班牙和英国,封锁的影响是相反的方向,也就是说,他们经历了明显更高的与新型冠状病毒肺炎有关的总数和每天每百万人的死亡,比瑞典封锁后。我们的研究结果表明,全国范围内的封锁对与新型冠状病毒肺炎有关的总死亡人数和每天每百万人的死亡人数的影响因国而异。



监测政府干预以遏制

新型冠状病毒肺炎的影响: 

一个定量的方法


原文标题:

Monitoring the Impacts of Government Interventions to Contain COVID-19: A Quantitative Approach

地址:

https://arxiv.org/abs/2006.12177

作者:

Shuo Wang,Xian Yang,Yuan Huang,Ling Li,Zhongzhao Teng,Yike Guo


Abstract:Monitoring the evolving impacts of non-pharmaceutical intervention measures requires fine-grained estimation of transmission dynamics. We propose a framework to estimate instantaneous reproduction number R_t using Bayesian inference upon a renewal process, disentangling the R_t reduction into mitigation and suppression factors for quantifying their impacts at a finer granularity. Investigating the impacts of intervention measures of European countries, the United States and Wuhan with the framework, we reveal the effects of interventions in Europe and alert that 30 states in the United States are facing resurgence risks.

摘要:监测非药物干预措施不断变化的影响需要对传播动态进行细致的估计。我们提出了一个框架来估计瞬时再生数 r t,使用贝叶斯推断在更新过程中,将 r t 约简分解为缓解和抑制因素,以便在更细的粒度上量化它们的影响。通过对欧洲国家、美国和武汉干预措施影响的框架调查,揭示了欧洲干预措施的效果,并警示美国30个州正面临复苏风险。



集群内和集群间耦合平衡

对非线性网络系统性能的影响


原文标题:

Impact of intra and inter-cluster coupling balance on the performance of nonlinear networked systems

地址:

http://arxiv.org/abs/2006.11357

作者:

Jiachen Ye,Peng Ji,David Waxman,Wei Lin,Yamir Moreno


Abstract:The dynamical and structural aspects of cluster synchronization (CS) in complex systems have been intensively investigated in recent years. Here, we study CS of dynamical systems with intra and inter-cluster couplings. We propose new metrics that describe the performance of such systems and evaluate them as a function of the strength of the couplings within and between clusters. We obtain analytical results that indicate that spectral differences between the Laplacian matrices associated with the partition between intra and inter-couplings directly affect the proposed metrics of system performance. Our results show that the dynamics of the system might exhibit an optimal balance that optimizes its performance. Our work provides new insights into the way specific symmetry properties relate to collective behavior, and could lead to new forms to increase the controllability of complex systems and to optimize their stability.

摘要:近年来,人们对复杂系统中簇同步的动力学和结构性质进行了深入的研究。在这里,我们研究了具有簇内和簇间耦合的动态系统的 CS。我们提出新的度量标准来描述这些系统的性能,并将它们作为集群内部和集群之间耦合强度的函数来评估。我们得到的分析结果表明,谱差异之间的拉普拉斯矩阵相关的分割之间的内部和相互耦合直接影响系统性能的度量。我们的结果表明,系统的动态可能表现出一个最佳的平衡,以优化其性能。我们的工作对特定的对称性质与集体行为的关系提供了新的见解,并可能导致新的形式,以增加复杂系统的可控性和优化其稳定性。



美国、亚洲和欧洲新型冠状病毒肺炎

流行的时间数据系列表明,

SARS-CoV-2 Spike D614G 变异

具有选择性


原文标题:

Temporal data series of COVID-19 epidemics in the USA, Asia and Europe suggests a selective sweep of SARS-CoV-2 Spike D614G variant

地址:

http://arxiv.org/abs/2006.11609

作者:

Taima N. Furuyama,Fernando Antoneli,Isabel M. V. G. Carvalho,Marcelo R. S. Briones,Luiz M. R. Janini


Abstract:The COVID-19 pandemic started in Wuhan, China, and caused the worldwide spread of the RNA virus SARS-CoV-2, the causative agent of COVID-19. Because of its mutational rate, wide geographical distribution, and host response variance this coronavirus is currently evolving into an array of strains with increasing genetic diversity. Most variants apparently have neutral effects for disease spread and symptoms severity. However, in the viral Spike protein, which is responsible for host cell attachment and invasion, an emergent variant, containing the amino acid substitution D to G in position 614 (D614G), was suggested to increase viral infection capability. To test whether this variant has epidemiological impact, the temporal distributions of the SARS-CoV-2 samples bearing D or G at position 614 were compared in the USA, Asia and Europe. The epidemiological curves were compared at early and late epidemic stages. At early stages, where containment measures were still not fully implemented, the viral variants are supposed to be unconstrained and its growth curves might approximate the free viral dynamics. Our analysis shows that the D614G prevalence and the growth rates of COVID-19 epidemic curves are correlated in the USA, Asia and Europe. Our results suggest a selective sweep that can be explained, at least in part, by a propagation advantage of this variant, in other words, that the molecular level effects of D614G have sufficient impact on population transmission dynamics as to be detected by differences in rate coefficients of epidemic growth curves.

摘要:新型冠状病毒肺炎病毒大流行始于中国武汉,引起了 RNA 病毒 SARS-CoV-2的全球传播,SARS-CoV-2是新型冠状病毒肺炎病毒的病原体。由于其突变率,广泛的地理分布和宿主反应方差,这种冠状病毒目前正在演变为一系列的菌株增加遗传多样性。大多数变异显然对疾病传播和症状严重性有中性影响。然而,在负责宿主细胞附着和侵袭的病毒穗蛋白中,一个突变体,在614位点(D614G)含有氨基酸替代的 d 到 g,提高了病毒的感染能力。为了检验这一变异是否具有流行病学影响,我们比较了美国、亚洲和欧洲614位带 d 或 g 的 SARS-CoV-2样品的时间分布。比较了流行病学早期和晚期的流行曲线。在早期阶段,遏制措施仍然没有完全实施,病毒变异被认为是不受约束的,它的生长曲线可能接近自由病毒动力学。我们的分析表明,在美国、亚洲和欧洲,D614G 流行率和新型冠状病毒肺炎 / 艾滋病流行曲线的增长率是相关的。我们的研究结果表明,选择性扫描至少可以部分地解释这种变异的传播优势,换句话说,D614G 的分子水平效应对种群传播动力学有足够的影响,可以通过流行病增长曲线速率系数的差异来检测。



墨西哥的新型冠状病毒肺炎: 

流行病网络


原文标题:

COVID-19 in Mexico: A Network of Epidemics

地址:

http://arxiv.org/abs/2006.11635

作者:

Guillermo de Anda-Jáuregui


Abstract:Mexico, like the rest of the world, is currently facing the The COVID-19 pandemic. Given the size of its territory, the efforts to contain the disease have involved both national and regional measures. For this work, the curves of daily new cases of each municipality reported by the federal government were compared. We found that 114 municipalities form a large network of statistically dependent epidemic phenomena. Based on the network's modular structure, these 114 municipalities can be split into four distinct communities of coordinated epidemic phenomena. These clusters are not limited by geographical proximity. These findings can be helpful for public health officials for the evaluation of past strategies and the development of new directed interventions.

摘要:墨西哥和世界其他地区一样,目前正面临新型冠状病毒肺炎流感大流行。鉴于其领土面积之大,控制该疾病的努力涉及国家和区域措施。对于这项工作,每个市政府报告的每日新病例曲线进行了比较。我们发现,114个城市形成了一个庞大的网络统计依赖的流行病现象。根据网络的模块结构,这114个城市可以分为四个不同的协调流行现象社区。这些集群不受地理邻近性的限制。这些发现可以帮助公共卫生官员评估过去的战略和发展新的指导干预措施。



数据驱动的分析: 

封锁是否遏制了

新型冠状病毒肺炎在印度的传播


原文标题:

Did the lockdown curb the spread of COVID-19 infection rate in India: A data-driven analysis

地址:

http://arxiv.org/abs/2006.12006

作者:

Dipankar Mondal,Siddhartha P. Chakrabarty


Abstract:In order to analyze the effectiveness of three successive nationwide lockdown enforced in India, we present a data-driven analysis of four key parameters, reducing the transmission rate, restraining the growth rate, flattening the epidemic curve and improving the health care system. These were quantified by the consideration of four different metrics, namely, reproduction rate, growth rate, doubling time and death to recovery ratio. The incidence data of the COVID-19 (during the period of 2nd March 2020 to 31st May 2020) outbreak in India was analyzed for the best fit to the epidemic curve, making use of the exponential growth, the maximum likelihood estimation, sequential Bayesian method and estimation of time-dependent reproduction. The best fit (based on the data considered) was for the time-dependent approach. Accordingly, this approach was used to assess the impact on the effective reproduction rate. The period of pre-lockdown to the end of lockdown 3, saw a45% reduction in the rate of effective reproduction rate. During the same period the growth rate reduced from 393% during the pre-lockdown to 33% after lockdown 3, accompanied by the average doubling time increasing form 4-6 days to 12-14 days. Finally, the death-to-recovery ratio dropped from 0.28 (pre-lockdown) to 0.08 after lockdown 3. In conclusion, all the four metrics considered to assess the effectiveness of the lockdown, exhibited significant favourable changes, from the pre-lockdown period to the end of lockdown 3. Analysis of the data in the post-lockdown period with these metrics will provide greater clarity with regards to the extent of the success of the lockdown.

摘要:为了分析印度连续三次全国性封锁的有效性,我们提出了四个关键参数的数据驱动分析,降低传播率,抑制增长率,平缓流行曲线和改善卫生保健系统。这些被量化的考虑四个不同的指标,即繁殖率,生长率,倍增时间和死亡恢复率。对印度新型冠状病毒肺炎爆发的发病率数据(2020年3月2日至2020年5月31日期间)进行了分析,以寻找与疫情曲线的最佳拟合,利用指数增长、最大似然估计、序贯贝叶斯方法和时间依赖性繁殖的估计。最佳拟合(基于所考虑的数据)是时间相关的方法。因此,这种方法被用来评估对有效繁殖率的影响。从禁闭前到禁闭3结束的这段时间里45% 有效繁殖率下降。在同一时期,生长率从393% 在禁闭前33% 在禁闭3号之后,伴随着平均倍增时间的形式 4-6 天到12-14 天最后,死亡与康复的比率从0.28 到0.08 。在3号禁闭室之后。总而言之,所有评估封锁有效性的四个指标,从封锁前期到封锁3结束,都表现出了显著的有利变化。使用这些指标对封锁后期间的数据进行分析,可以更清楚地了解封锁的成功程度。



森林砍伐与世界人口可持续性: 

定量分析


原文标题:

Deforestation and world population sustainability: a quantitative analysis

地址:

http://arxiv.org/abs/2006.12202

作者:

Mauro Bologna,Gerardo Aquino


Abstract:In this paper we afford a quantitative analysis of the sustainability of current world population growth in relation to the parallel deforestation process adopting a statistical point of view. We consider a simplified model based on a stochastic growth process driven by a continuous time random walk, which depicts the technological evolution of human kind, in conjunction with a deterministic generalised logistic model for humans-forest interaction and we evaluate the probability of avoiding the self-destruction of our civilisation. Based on the current resource consumption rates and best estimate of technological rate growth our study shows that we have very low probability, less than 10% in most optimistic estimate, to survive without facing a catastrophic collapse.

摘要:本文采用统计学的观点,对当前世界人口增长与平行毁林过程的可持续性进行了定量分析。我们考虑了一个简化的模型,该模型基于连续时间随机游走驱动的随机增长过程,描述了人类的技术进化,并结合一个确定性的广义逻辑斯谛模型来描述人类与森林的相互作用,我们评估了避免人类文明自我毁灭的可能性。基于当前的资源消耗率和对技术增长率的最佳估计,我们的研究表明,我们在不面临灾难性崩溃的情况下生存的概率非常低,最乐观的估计不到10%。



时间依赖和时间独立的 SIR 模型

应用于在阿根廷、巴西、哥伦比亚、

墨西哥和南非爆发的新型冠状病毒肺炎


原文标题:

Time-dependent and time-independent SIR models applied to the COVID-19 outbreak in Argentina, Brazil, Colombia, Mexico and South Africa

地址:

https://arxiv.org/abs/2006.12479

作者:

Nana Geraldine Cabo Bizet,Damián Kaloni Mayorga Peña


Abstract:We consider the SIR epidemiological model applied to the evolution of COVID-19 with two approaches. In the first place we fit a global SIR model, with time delay, and constant parameters throughout the outbreak, including the contagion rate. The contention measures are reflected on an effective reduced susceptible populationNeff. In the second approach we consider a time-dependent contagion rate that reflects the contention measures either through a step by step fitting process or by following an exponential decay. In this last model the population is considered the one of the country N. In the linear region of the differential equations, when the total population N is large the predictions are independent of N. We apply these methodologies to study the spread of the pandemic in Argentina, Brazil, Colombia, Mexico, and South Africa for which the infection peaks are yet to be reached. In all of these cases we provide estimates for the reproduction and recovery rates. The scenario for a time varying contagion rate is optimistic, considering that reasonable measures are taken such that the reproduction factor R0 decreases exponentially. The measured values for the recovery rate γ are reported finding a universality of this parameter over various countries. We discuss the correspondence between the global SIR with effective population Neff and the evolution of the time local SIR.

摘要:我们考虑用两种方法将 SIR 流行病学模型应用于 covid-19的进化。首先,我们拟合一个全局 SIR 模型,具有时间延迟,并且在整个爆发过程中参数不变,包括传染率。争夺措施反映在有效减少易感种群上Neff. 在第二种方法中,我们考虑一个依赖于时间的传染率,它通过一个逐步拟合的过程或者遵循一个指数衰减来反映争论的度量。在最后一个模型中,人口被认为是国家的一部分N.我们应用这些方法来研究这种流行病在阿根廷、巴西、哥伦比亚、墨西哥和南非的传播情况,这些国家的感染高峰尚未到来。在所有这些情况下,我们提供了复制和恢复率的估计。考虑到采取了合理的措施,使再生产因素得以保留,时变传染率的假设是乐观的R0 回收率的测量值γ ,本文报道了这个参数在各国的普适性,并讨论了全局 SIR 与有效总体之间的对应关系Neff 以及时间演变的本地 SIR。



通风减少病毒传播的必要性简单量化


原文标题:

Necessity of ventilation for mitigating virus transmission quantified simply

地址:

http://arxiv.org/abs/2006.11651

作者:

Eric G. Blackman,Gourab Ghoshal


Abstract:To mitigate the SARS-CoV-2 pandemic, officials have employed social distancing and stay-at-home measures. Less attention has focused on ventilation. Effective distancing practices for open spaces may be ineffective for poorly ventilated spaces, both of which are commonly filled with turbulent air. While turbulence initially reduces the risk of infection near a virion-source, it eventually increases the exposure risk for all occupants in a space without ventilation. Here we estimate the time-scale for virions injected into a room of turbulent air to infect an occupant, distinguishing cases of low vs. high initial virion mass loads and virion-destroying vs. virion-reflecting walls. An open window typifies ventilation and we show that its minimum area needed to ensure safety depends only on the ratio of total viral load to threshold load for infection. Our order-of-magnitude estimates complement more detailed approaches.

摘要:为了缓解 SARS-CoV-2大流行,官员们采用了社会疏远和居家措施。人们很少关注通风问题。开放空间的有效距离做法可能对通风不良的空间无效,这两个空间通常都充满了湍流空气。虽然湍流最初会降低病毒源附近感染的风险,但最终会增加没有通风设备的空间中所有居住者的暴露风险。在这里,我们估计时间尺度的病毒注入一个房间的湍流空气感染一个居住者,区分情况低与高初始病毒质量负荷和病毒破坏与病毒反射墙。开窗通气是典型的通气方式,我们发现确保通气安全所需的最小面积仅取决于病毒载量与感染阈值载量的比值。我们的数量级估计补充了更详细的方法。



Lévy 漫步超扩散开始的普遍性起源


原文标题:

The origin of universality in the onset of superdiffusion in Lévy walks

地址:

http://arxiv.org/abs/2006.11932

作者:

Asaf Miron


Abstract:Superdiffusion arises when complicated, correlated and noisy motion at the microscopic scale conspires to yield peculiar dynamics at the macroscopic scale. It ubiquitously appears in a variety of scenarios, spanning a broad range of scientific disciplines. The approach of superdiffusive systems towards their long-time, asymptotic behavior was recently studied using the Lévy walk of order1<β<2, revealing a universal transition at the critical βc=3/2. Here, we investigate the origin of this transition and identify two crucial ingredients: a finite velocity which couples the walker's position to time and a corresponding transition in the fluctuations of the number of walks n completed by the walker at time t.

摘要:当微观尺度的复杂、相关和嘈杂的运动在宏观产生奇特的动力学时,就会产生超扩散。它无处不在地出现在各种各样的场景中,跨越了广泛的科学分支。研究了超扩散系统长时间渐近行为的逼近问题1<β<2,本文通过对中国传统文化的分析,揭示了中国传统文化在关键时刻的普遍转变,并对中国传统文化的发展提出了建议βc=3/2.在这里,我们研究了这种转变的起源,并确定了两个关键因素: 有限速度与步行者的位置关联到时间,以及相应的步行次数波动的转变n 由行驶完成的t。



三维湍流中速度环流的概率分布


原文标题:

Probability Distribution of Velocity Circulation in Three Dimensional Turbulence

地址:

http://arxiv.org/abs/2006.12008

作者:

Alexander Migdal


Abstract:We elaborate the statistical field theory of Turbulence suggested in the previous paper cite{M20a}. We clarify and simplify the basic Energy pumping equation of that theory and study mathematical properties of singular field configuration (instanton) which determine the tails of PDF for the velocity circulation around large loopC in isotropic turbulence at highest Reynolds numbers. Explicit analytic solution is found for the Clebsch instanton in an Euler equation for a planar loop circulation problem. This solution for vorticity is has a term proportional to a delta function in normal direction to the minimal surface bounded by the loop. The smoothing of δ functions in the vorticity in the full Navier-Stokes equations is investigated and exponential profile of smoothed singularity is found.
The PDF for circulation is now an infinite sum of decreasing exponential terms $EXP{- n |w|}sqrt{frac{n}{|w|}}$, with 
w=ΓΓ0[C], and Γ0[C]∼AC−−−√ with minimal area AC. The leading term fits with adjusted R2=0.9999 the PDF tail found in DNS over more than six orders of magnitude. The area dependence of the ratio of the circulation moments M8/M6 fits with adjusted R2=0.9996 the DNS in inertial range of square loop sizes from 100 to 500 Kolmogorov scales.
Thus, our theory explains DNS with high degree or confidence.
For a flat loop we derive two-dimensional integral equation for the dependence of the scale 
Γ0[C] of circulation as a function of the shape of the loop (aspect ratio for rectangular loop

摘要:对前人提出的湍流统计场理论进行了详细的阐述。阐明和简化了该理论的基本能量抽运方程,并研究了决定大回路周围速度环流概率密度函数(PDF)尾部的奇异场结构(瞬子)的数学性质C 在各向同性湍流中达到最高雷诺数。给出了平面环路环流问题欧拉方程中克莱布施瞬子的显式解析解。这个涡量的解决方案是有一个项成正比的三角函数在法向的最小曲面有界的回路。平滑δ 研究了全纳维-斯托克斯方程涡量中的函数,发现了光滑奇点的指数分布。

发行量的 PDF 现在是指数递减项的无穷和 $EXP {-n | w | | } sqrt { frac { n }{ | w | } $和w=ΓΓ0[C],及Γ0[C]∼AC−−−√ 最小面积AC.主要的术语适合调整R2=0.9999 。在超过6个数量级的时间内在 DNS 中定位 PDF。环流矩比值的面积相关性M8/M6 与调整过的吻合R2=0.9996 惯性范围内的正方形回路尺寸的 dn100 到500 柯尔莫哥洛夫尺度。因此,我们的理论对 DNS 的解释具有高度的可信度。

对于一个平面环,我们推导出尺度依赖性的二维积分方程Γ0[C] 矩形环的长宽比。



驱动谐振子的动力学耦合了

随机场中成对相互作用的伊辛自旋


原文标题:

The dynamics of a driven harmonic oscillator coupled to pairwise interacting Ising spins in random fields

地址:

http://arxiv.org/abs/2006.12429

作者:

Paul Zech,Andreas Otto,Günter Radons


Abstract:In general we are interested in dynamical systems coupled to complex hysteresis. Therefore as a first step we did some investigation on the dynamics of a periodically driven damped harmonic oscillator coupled to independent Ising spins with a local quenched disorder at zero temperature in the past. Although such a system does not produce hysteresis, we showed how to characterize the dynamics of such a piecewise-smooth system, specially in case of a large number of spins [P. Zech, A. Otto, and G. Radons, Phys. Rev. E101,042217 (2020)]. In this paper we want to extend our model to spins dimers, thus spins with pairwise interaction. We will show in which cases two interacting spins can show elementary hysteresis and we will give a connection to the ac{PM}, when superpose a infinite number of spin-pairs in the thermodynamic limit. We will see, that this will lead us to a dynamical system with an additional hysteretic force in form of a play operator. By using methods from general chaos theory, piecewise-smooth system theory and statistics we will investigate the chaotic behavior of the dynamical system for a few spins and also in case of larger number of spins by calculating bifurcation diagrams, fractal dimensions and self-averaging properties. In doing so we show, how the dynamical properties of the piecewise-smooth system for a large number of spins differs from the system in its thermodynamic limit.

摘要:一般来说,我们感兴趣的动力系统耦合的复杂滞后。因此,作为第一步,我们做了一些动力学的研究,周期性驱动的阻尼谐振子与独立的伊辛自旋耦合,在过去的零温下局部淬火无序。虽然这样一个系统不产生滞后,我们展示了如何刻画这样一个分段光滑系统的动力学性质,特别是在大量自旋的情况下[ p. Zech,a. Otto,和 g. Radons,Phys。101,042217(2020)]. 在这篇论文中,我们希望将我们的模型扩展到自旋二聚体,从而使自旋具有成对相互作用。我们将展示在哪些情况下相互作用的自旋可以显示出基本的滞后现象,并且我们将给出与 ac { PM }的联系,当无限多的自旋对叠加在热力学极限中时。我们将看到,这将引导我们到达一个带有额外的滞后力的动力系统。利用一般混沌理论、分段光滑系统理论和统计学的方法,通过计算分叉图、分形维数和自平均特性,研究了动力系统在少数自旋和大自旋情况下的混沌行为。在这个过程中,我们展示了大量自旋的分段光滑系统的动力学性质与其自旋热力学极限的不同之处。



基于光学偶极力阱释放和捕获

的空气微粒快速质量测定技术


原文标题:

Technique for rapid mass determination of airborne micro-particles based on release and recapture from an optical dipole force trap

地址:

http://arxiv.org/abs/2006.12429

作者:

Gehrig Carlse,Kevin B. Borsos,Hermina C. Beica,Thomas Vacheresse,Alex Pouliot,Jorge Perez-Garcia,Andrejs Vorozcovs,Boris Barron,Shira Jackson,Louis Marmet,A. Kumarakrishnan


AbstractWe describe a new method for the rapid determination of the mass of particles confined in a free-space optical dipole-force trap. The technique relies on direct imaging of drop-and-restore experiments without the need for a vacuum environment. In these experiments, the trapping light is rapidly shuttered with an acousto-optic modulator causing the particle to be released from and subsequently recaptured by the trapping force. The trajectories of both the falls and restorations, imaged using a high-speed CMOS sensor, are combined to determine the particle mass. We corroborate these measurements using an analysis of position autocorrelation functions of the trapped particles. We report a statistical uncertainty of less than 2% for masses on the order of5×10−14 kg using a data acquisition time of approximately 90 seconds.

摘要:本文介绍了一种快速测定自由空间光学偶极力阱中粒子质量的新方法。该技术依赖于直接成像的跌落和恢复实验,而不需要一个真空环境。在这些实验中,捕获光被声光调制器快速关闭,粒子被释放出来,随后被捕获力重新捕获。利用一个高速 CMOS 传感器成像,将跌落和修复的轨迹结合起来,以确定粒子的质量。我们通过分析囚禁粒子的位置自相关函数来证实这些测量结果。我们报告的统计不确定性小于2% 的群众的秩序5×10−14 kg,使用大约90秒的数据采集时间。



滑动分析中的半柔性聚合物:

凹入转变,转换和活性的作用


原文标题:

Semiflexible polymer in a gliding assay: reentrant transition, role of turnover and activity

地址:

http://arxiv.org/abs/2006.11603

作者:

Amir Shee,Nisha Gupta,Abhishek Chudhuri,Debasish Chaudhuri


Abstract:We consider a model of an extensible semiflexible filament moving in two dimensions on a motility assay of motor proteins represented explicitly as active harmonic linkers. Their heads bind stochastically to polymer segments within a capture radius, and extend along the filament in a directed fashion before detaching. Both the extension and detachment rates are load-dependent and generate an active drive on the filament. The filament undergoes a first order phase transition from open chain to spiral conformations and shows a reentrant behavior in both the active extension and the turnover, defined as the ratio of attachment-detachment rates. Associated with the phase transition, the size and shape of the polymer changes non-monotonically, and the relevant autocorrelation functions display double-exponential decay. The corresponding correlation times show a maximum signifying the dominance of spirals. The orientational dynamics captures the rotation of spirals, and its correlation time decays with activity as a power law.

摘要:我们考虑一个可扩展的半柔性灯丝在二维运动的模型上的运动测定的马达蛋白显式表示为活跃的谐波连接器。它们的头随机地绑在捕获半径范围内的聚合物环节上,在分离之前沿着细丝定向延伸。伸展速率和分离速率都与载荷有关,并在灯丝上产生主动驱动。丝状体经历了从开链到螺旋构象的一级相变过程,在有效扩展和周转过程中都表现出重入行为,这种行为被定义为附着-分离率的比值。聚合物的尺寸和形状随相变呈非单调变化,相应的自相关函数呈双指数衰减。相应的相关时间显示了螺旋占主导地位的最大值。定向动力学捕获螺旋旋转,其相关时间随活动呈幂律衰减。



异常的血小板运输和脂肪尾分布


原文标题:

Anomalous Platelet Transport & Fat-Tailed Distributions

地址:

http://arxiv.org/abs/2006.11755

作者:

Christos Kotsalos,Karim Zouaoui Boudjeltia,Ritabrata Dutta,Jonas Latt,Bastien Chopard


Abstract:The transport of platelets in blood is commonly assumed to obey an advection-diffusion equation. Here we propose a disruptive view, by showing that the random part of their velocity is governed by a fat-tailed probability distribution, usually referred to as a L'evy flight. Although for small spatio-temporal scales, it is hard to distinguish it from the generally accepted "red blood cell enhanced" Brownian motion, for larger systems this effect is dramatic as the standard approach may underestimate the flux of platelets by several orders of magnitude, compromising in particular the validity of current platelet function tests.

摘要:血小板在血液中的运输通常被认为遵循一个平流-扩散方程。在这里,我们提出了一个破坏性的观点,通过展示它们速度的随机部分是由厚尾概率分布控制的,通常被称为 l‘ evy 飞行。虽然对于小的时空尺度,很难区分它与普遍接受的“红细胞增强”布朗运动,对于较大的系统,这种效应是戏剧性的,因为标准的方法可能低估血小板的流量几百万数量级,特别是降低了当前血小板功能测试的有效性。



基于两国链接追踪抽样

的跨国社会领域测量


原文标题:

Measuring transnational social fields through binational link-tracing sampling

地址:

https://arxiv.org/abs/2006.11380

作者:

Marian-Gabriel Hâncean,Miranda J. Lubbers,José Luis Molina


Abstract:We advance binational link-tracing sampling design, an innovative data collection methodology for sampling from transnational social fields, i.e., transnational networks embedding migrants and non-migrants. This paper shows the practical challenges of such a design, the representativeness of the samples and the qualities of the resulted networks. We performed 303 face-to-face structured interviews on sociodemographic variables, migration trajectories and personal networks of people living in a Romanian migration sending community (Dâmboviţa) and in a migration receiving Spanish town (Castellón), simultaneously in both sites. Inter-connecting the personal networks, we built a multi-layered complex network structure embedding 4,855 nominated people, 5,477 directed ties (nominations) and 2,540 edges. Results indicate that the participants' unique identification is a particularly difficult challenge, the representativeness of the data is not optimal (homophily on observed attributes was detected in the nomination patterns), and the relational and attribute data allow to explore the social organization of the Romanian migrant enclave in Castellón, as well as its connectivity to other places. Furthermore, we provide methodological suggestions for improving link-tracing sampling from transnational networks of migration. Our research contributes to the emerging efforts of applying social network analysis to the study of international migration.

摘要:我们提出了两国链接追踪抽样设计,这是一种创新的数据收集方法,用于跨国社会领域的抽样,即包含移民和非移民的跨国网络。本文指出了这种设计的实际挑战,样本的代表性和由此产生的网络的质量。我们进行了303次面对面的结构化访谈,内容涉及社会人口变量、移民轨迹和个人网络,这些人生活在罗马尼亚移民输出社区(d ^ ambovi c { t } a)和移民接收西班牙城镇(Castell‘ on) ,同时在这两个地点进行。通过个人网络的相互连接,我们建立了一个多层次的复杂网络结构,包括4855个提名人,5477个有向联系(提名)和2540个边。结果表明,参与者的独特身份识别是一个特别困难的挑战,数据的代表性不是最佳的(在提名模式中发现了观察到的属性的同相性) ,关系和属性数据允许探索 Castell‘ on 罗马尼亚移民飞地的社会组织及其与其他地方的连通性。此外,我们还为改进跨国移民网络中的链接追踪抽样提供了方法上的建议。我们的研究有助于将社会网络分析应用于国际移民研究。



隐性众包识别

在线社交网络中的滥用行为


原文标题:

Implicit Crowdsourcing for Identifying Abusive Behavior in Online Social Networks

地址:

https://arxiv.org/abs/2006.11456

作者:

Abiola Osho,Ethan Tucker,George Amariucai


Abstract:The increased use of online social networks for the dissemination of information comes with the misuse of the internet for cyberbullying, cybercrime, spam, vandalism, amongst other things. To proactively identify abuse in the networks, we propose a model to identify abusive posts by crowdsourcing. The crowdsourcing part of the detection mechanism is implemented implicitly, by simply observing the natural interaction between users encountering the messages. We explore the node-to-node spread of information on Twitter and propose a model that predicts the abuse level (abusive, hate, spam, normal) associated with the tweet by observing the attributes of the message, along with those of the users interacting with it. We demonstrate that the difference in users' interactions with abusive posts can be leveraged in identifying posts of varying abuse levels.

摘要:随着在线社交网络用于信息传播的增加,网络被滥用于网络欺凌、网络犯罪、垃圾邮件、破坏公物等等。为了主动识别网络中的滥用行为,我们提出了一个通过众包识别滥用帖子的模型。检测机制的众包部分是隐式实现的,通过简单地观察遇到消息的用户之间的自然交互。我们研究了 Twitter 上信息的节点到节点的传播,并提出了一个模型,通过观察消息的属性以及与之交互的用户的属性,来预测与该消息相关的滥用程度(辱骂、仇恨、垃圾邮件、正常)。我们证明,用户与滥发帖子互动的差异可以用来识别不同程度的滥用帖子。



在黑暗网络中挖掘用户

交互模式来预测企业网络事件


原文标题:

Mining user interaction patterns in the darkweb to predict enterprise cyber incidents

地址:

https://arxiv.org/abs/1909.11592

作者:

Soumajyoti Sarkar,Mohammad Almukaynizi,Jana Shakarian,Paulo Shakarian


Abstract:With rise in security breaches over the past few years, there has been an increasing need to mine insights from social m。edia platforms to raise alerts of possible attacks in an attempt to defend conflict during competition. In this study, we attempt to build a framework that utilizes unconventional signals from the darkweb forums by leveraging the reply network structure of user interactions with the goal of predicting enterprise related external cyber attacks. We use both unsupervised and supervised learning models that address the challenges that come with the lack of enterprise attack metadata for ground truth validation as well as insufficient data for training the models. We validate our models on a binary classification problem that attempts to predict cyber attacks on a daily basis for an organization. Using several controlled studies on features leveraging the network structure, we measure the extent to which the indicators from the darkweb forums can be successfully used to predict attacks. We use information from 53 forums in the darkweb over a span of 17 months for the task. Our framework to predict real world organization cyber attacks of 3 different security events, suggest that focusing on the reply path structure between groups of users based on random walk transitions and community structures has an advantage in terms of better performance solely relying on forum or user posting statistics prior to attacks.

摘要:在过去的几年里,随着数字证书认证机构数量的上升,人们越来越需要从社交媒体平台中挖掘洞察力,提高对可能发生的攻击的警报,以便在竞争中保护冲突。在这项研究中,我们尝试建立一个框架,利用黑暗网络论坛的非常规信号,利用用户交互的回复网络结构,以预测企业相关的外部网络攻击。我们同时使用无监督模型和监督式学习模型来解决缺乏企业攻击元数据进行实地验证以及培训模型的数据不足所带来的挑战。我们在一个二元分类问题上验证了我们的模型,该问题试图每天为组织预测网络攻击。通过对网络结构特征的一些受控研究,我们测量了来自黑暗网络论坛的指标能够成功用于预测攻击的程度。我们在17个月的时间里使用了53个论坛的暗网信息来完成这项任务。我们的框架预测现实世界组织的3个不同的安全事件的网络攻击,建议关注用户组之间的回复路径结构基于随机漫步过渡和社区结构的优势在于更好的性能完全依赖于论坛或用户发布攻击前的统计数据。



用于检索流量 Tweets 的自动查询优化


原文标题:

Automatic Query Optimization for Retrieving Traffic Tweets

地址:

https://arxiv.org/abs/2006.11887

作者:

Emory Hufbauer,Hana Khamfroush


Abstract:Twitter, like many social media and data brokering companies, makes their data available through a search API (application programming interface). In addition to filtering results by date and location, researchers can search for tweets with specific content with a boolean text query, using {it AND}, {it OR}, and {it NOT} operators to select the combinations of phrases which must, or must not, appear in matching tweets. This boolean text search system is not at all unique to Twitter and is found in many different contexts, including academic, legal, and medical databases, however it is stretched to its limits in Twitter's use case because of the relative volume and brevity of tweets. In addition, the semi-automated use of such systems was well studied under the topic of Information Retrieval during the 1980s and 1990s, however the study of such systems has greatly declined since that time. As such, we propose updated methods for automatically selecting and refining complex boolean search queries that can isolate relevant results with greater specificity and completeness. Furthermore, we present preliminary results of using an optimized query to collect a sample of traffic-incident-related tweets, along with the results of manually classifying and analyzing them.

摘要:像许多社交媒体和数据代理公司一样,Twitter 通过一个搜索 API (应用程序编程接口)提供数据。除了按日期和位置过滤结果,研究人员还可以通过布尔文本查询搜索具有特定内容的 tweets,使用{ it AND }、{ it OR }和{ it NOT }操作符来选择必须或不能出现在匹配 tweets 中的短语组合。这个布尔型文本搜索系统并不是 Twitter 独有的,可以在很多不同的环境中找到,包括学术、法律和医疗数据库,然而在 Twitter 的使用案例中,由于推文的相对数量和简洁性,它已经达到了极限。此外,在20世纪80年代和90年代,这种系统的半自动化使用在信息检索的主题下得到了很好的研究,然而自那时以来,这种系统的研究已经大大减少了。因此,我们提出了更新的方法,自动选择和精炼复杂的布尔搜索查询,可以隔离相关的结果更具有特异性和完整性。此外,我们提出了初步的结果,使用优化的查询收集交通事件相关的 tweets 样本,以及手动分类和分析的结果。



利用图形神经网络学习传染源的研究


原文标题:

Finding Patient Zero: Learning Contagion Source with Graph Neural Networks

地址:

https://arxiv.org/abs/2006.11913

作者:

Chintan Shah,Nima Dehmamy,Nicola Perra,Matteo Chinazzi,Albert-László Barabási,Alessandro Vespignani,Rose Yu


Abstract:Locating the source of an epidemic, or patient zero (P0), can provide critical insights into the infection's transmission course and allow efficient resource allocation. Existing methods use graph-theoretic centrality measures and expensive message-passing algorithms, requiring knowledge of the underlying dynamics and its parameters. In this paper, we revisit this problem using graph neural networks (GNNs) to learn P0. We establish a theoretical limit for the identification of P0 in a class of epidemic models. We evaluate our method against different epidemic models on both synthetic and a real-world contact network considering a disease with history and characteristics of COVID-19. % We observe that GNNs can identify P0 close to the theoretical bound on accuracy, without explicit input of dynamics or its parameters. In addition, GNN is over 100 times faster than classic methods for inference on arbitrary graph topologies. Our theoretical bound also shows that the epidemic is like a ticking clock, emphasizing the importance of early contact-tracing. We find a maximum time after which accurate recovery of the source becomes impossible, regardless of the algorithm used.

摘要:找到流行病的源头,或者说零号病人(P0) ,可以对感染的传播过程提供关键的洞察力,从而实现有效的资源配置。现有的方法使用图论中心性度量和代价高昂的消息传递算法,需要了解底层动态及其参数。本文利用图神经网络(GNNs)学习 P0,重新研究了这个问题。建立了一类传染病模型中 P0判别的理论极限。我们评估我们的方法针对不同的传染病模型在合成和现实世界接触网络考虑一个疾病的历史和特点的新型冠状病毒肺炎。我们观察到 GNNs 能够识别接近理论界限的精度,没有明确的输入动力学或其参数。此外,GNN 比传统的图拓扑推理方法快100倍以上。我们的理论界限还表明,这种流行病就像一个滴答作响的时钟,强调了早期接触追踪的重要性。我们发现一个最大的时间之后,准确恢复源变得不可能,无论使用的算法。



(非)稳定网络的 Nash 均衡


原文标题:

Nash Equilibria on (Un)Stable Networks

地址:

https://arxiv.org/abs/1901.00373

作者:

Anton Badev


Abstract:In response to a change, individuals may choose to follow the responses of their friends or, alternatively, to change their friends. To model these decisions, consider a game where players choose their behaviors and friendships. In equilibrium, players internalize the need for consensus in forming friendships and choose their optimal strategies on subsets of k players - a form of bounded rationality. The k-player consensual dynamic delivers a probabilistic ranking of a game's equilibria, and, via a varying k, facilitates estimation of such games. Applying the model to adolescents' smoking suggests that: (a.) the response of the friendship network to changes in tobacco price amplifies the intended effect of price changes on smoking, (b.) racial desegregation of high-schools decreases the overall smoking prevalence, (c.) peer effect complementarities are substantially stronger between smokers compared to between non-smokers. (d.) the magnitude of the spillover effects from small scale policies targeting individuals' smoking choices are roughly double compared to the scale of these policies.

摘要:作为对变化的回应,个体可能会选择跟随他们朋友的回应,或者,改变他们的朋友。为了建立这些决定的模型,考虑一个游戏,其中玩家选择他们的行为和友谊。在均衡状态下,玩家在建立友谊时内在地需要达成共识,并在 k 个玩家子集上选择他们的最佳策略,这是一种有限理性的形式。K- 玩家一致同意动态提供了一个游戏均衡的概率排名,并通过变化的 k,促进了这类游戏的估计。将该模型应用于青少年吸烟的研究表明: (a)友谊网络对烟草价格变化的反应放大了价格变化对吸烟的预期影响; (b)高中取消种族隔离降低了总体吸烟率; (c)吸烟者之间的同伴效应互补性明显高于非吸烟者。(d)针对个人吸烟选择的小规模政策的溢出效应大致是这些政策规模的两倍。



澳大利亚新型冠状病毒肺炎

流行引起的社区情绪动态研究


原文标题:

Examination of community sentiment dynamics due to covid-19 pandemic: a case study from Australia

地址:

https://arxiv.org/abs/2006.12185

作者:

Jianlong Zhou,Shuiqiao Yang,Chun Xiao,Fang Chen


Abstract:The outbreak of the novel Coronavirus Disease 2019 (COVID-19) has caused unprecedented impacts to people's daily life around the world. Various measures and policies such as lock-down and social-distancing are implemented by governments to combat the disease during the pandemic period. These measures and policies as well as virus itself may cause different mental health issues to people such as depression, anxiety, sadness, etc. In this paper, we exploit the massive text data posted by Twitter users to analyse the sentiment dynamics of people living in the state of New South Wales (NSW) in Australia during the pandemic period. Different from the existing work that mostly focuses the country-level and static sentiment analysis, we analyse the sentiment dynamics at the fine-grained local government areas (LGAs). Based on the analysis of around 94 million tweets that posted by around 183 thousand users located at different LGAs in NSW in five months, we found that people in NSW showed an overall positive sentimental polarity and the COVID-19 pandemic decreased the overall positive sentimental polarity during the pandemic period. The fine-grained analysis of sentiment in LGAs found that despite the dominant positive sentiment most of days during the study period, some LGAs experienced significant sentiment changes from positive to negative. This study also analysed the sentimental dynamics delivered by the hot topics in Twitter such as government policies (e.g. the Australia's JobKeeper program, lock-down, social-distancing) as well as the focused social events (e.g. the Ruby Princess Cruise). The results showed that the policies and events did affect people's overall sentiment, and they affected people's overall sentiment differently at different stages.

摘要:2019年新型冠状病毒病的爆发对世界各地人们的日常生活造成了前所未有的影响。新型冠状病毒肺炎病毒感染是一种传染病。各国政府实施了各种措施和政策,如封锁和社会疏远,以在大流行期间防治该疾病。这些措施和政策以及病毒本身都可能对人们造成不同的心理健康问题,如抑郁、焦虑、悲伤等。在这篇论文中,我们利用 Twitter 用户发布的大量文本数据来分析澳大利亚新南威尔士州(NSW)流感大流行期间人们的情绪动态。不同于现有的主要集中在国家层面和静态情绪分析的工作,我们分析情绪动态在细粒度的地方政府领域(lga)。根据对新南威尔士州不同地区的18.3万用户在5个月内发布的大约9400万条推文的分析,我们发现新南威尔士州的人们表现出了一种总体上积极的情感极性,新型冠状病毒肺炎流行病在流行期间减少了总体上积极的情感极性。对 LGAs 中情绪的细致分析发现,尽管在研究期间的大多数日子里,积极情绪占主导地位,但一些 LGAs 经历了从积极到消极的重大情绪变化。这项研究还分析了 Twitter 上热门话题所传递的情感动态,比如政府政策(比如澳大利亚的“就业守护者”计划、封锁、社会疏远)以及重点社会事件(比如“红宝石公主邮轮”)。结果表明,政策和事件确实影响了人们的整体情绪,并且在不同的阶段对人们的整体情绪有不同的影响。



考虑私有节点的

随机漫步社会网络性质估计


原文标题:

Estimating Properties of Social Networks via Random Walk considering Private Nodes

地址:

https://arxiv.org/abs/2006.12196

作者:

Kazuki Nakajima,Kazuyuki Shudo


AbstractAccurately analyzing graph properties of social networks is a challenging task because of access limitations to the graph data. To address this challenge, several algorithms to obtain unbiased estimates of properties from few samples via a random walk have been studied. However, existing algorithms do not consider private nodes who hide their neighbors in real social networks, leading to some practical problems. Here we design random walk-based algorithms to accurately estimate properties without any problems caused by private nodes. First, we design a random walk-based sampling algorithm that comprises the neighbor selection to obtain samples having the Markov property and the calculation of weights for each sample to correct the sampling bias. Further, for two graph property estimators, we propose the weighting methods to reduce not only the sampling bias but also estimation errors due to private nodes. The proposed algorithms improve the estimation accuracy of the existing algorithms by up to 92.6% on real-world datasets

摘要:准确地分析社会网络的图形属性是一个具有挑战性的任务,因为对图形数据的访问受到限制。为了应对这一挑战,人们研究了几种通过随机游动从少数样本中获得无偏估计的算法。然而,现有的算法没有考虑到隐藏在真实社会网络中邻居的私有节点,这就导致了一些实际问题。在这里,我们设计了基于随机漫步的算法,以准确地估计属性没有任何问题所造成的私有节点。首先,我们设计了一个基于随机游走的抽样算法,包括邻居选择,以获得具有马尔可夫性的样本,并计算每个样本的权重来校正抽样偏差。进一步,对于两个图的性质估计,我们提出了加权方法,以减少抽样偏差和估计误差由于私有节点。在真实数据集上,该算法的估计精度提高了92.6%。



亚洲国家的风险沟通: 

新型冠状病毒肺炎在 Twitter 上的演讲


原文标题:

Risk Communication in Asian Countries: COVID-19 Discourse on Twitter

地址:

https://arxiv.org/abs/2006.12218

作者:

Sungkyu Park,Sungwon Han,Jeongwook Kim,Mir Majid Molaie,Hoang Dieu Vu,Karandeep Singh,Jiyoung Han,Wonjae Lee,Meeyoung Cha


Abstract:COVID-19 has become one of the most widely talked about topics on social media. This research characterizes risk communication patterns by analyzing the public discourse on the novel coronavirus from four Asian countries: South Korea, Iran, Vietnam, and India, which suffered the outbreak to different degrees. The temporal analysis shows that the official epidemic phases issued by governments do not match well with the online attention on COVID-19. This finding calls for a need to analyze the public discourse by new measures, such as topical dynamics. Here, we propose an automatic method to detect topical phase transitions and compare similarities in major topics across these countries over time. We examine the time lag difference between social media attention and confirmed patient counts. For dynamics, we find an inverse relationship between the tweet count and topical diversity.

摘要:新型冠状病毒肺炎已经成为社交媒体上被广泛讨论的话题之一。这项研究通过分析来自四个亚洲国家: 韩国、伊朗、越南和印度的关于新型冠状病毒的公共话语来描述风险传播模式。时间分析表明,政府发布的官方流行病阶段并不能很好地匹配网上对新型冠状病毒肺炎的关注。这个发现需要通过新的方法来分析公共话语,比如时事动态。在这里,我们提出了一种自动检测局部相变的方法,并随着时间的推移比较这些国家的主要议题的相似性。我们调查了社交媒体关注度和确诊患者数量之间的时滞差异。在动态方面,我们发现了推文数量和主题多样性之间的反比关系。



当社会影响力促进群体智慧时


原文标题:

When social influence promotes the wisdom of crowds

地址:

https://arxiv.org/abs/2006.12471

作者:

Abdullah Almaatouq,M. Amin Rahimian,Abdulla Alhajri


Abstract:Questions regarding whether, and if so, under what conditions, groups exhibit ''crowd wisdom'' have spurred numerous studies in many disciplines, including management and organizational science, psychology, sociology, complex systems, and computer science. Substantial effort in previous research on these questions has focused on investigating the role of social influence in promoting the wisdom of the crowd or, conversely, leading the crowd astray. Specifically, many previous studies have sought to infer the importance of social influence network attributes (such as influence centralization) to explain the accuracy of collective estimates. In this paper, we argue that this approach is limited and can lead to inconsistent conclusions. Based on our theoretical analysis, numerical simulation, and reanalysis of four previously published experiments (which included a total of 4,002 human participants, organized in 131 independent groups), we demonstrate that the wisdom of crowds in estimation tasks depends on the interaction between the following two factors: (i) centralization of the social influence network, and (ii) the features of the estimation context---i.e., the distribution of the initial (pre-influence) estimates. Specifically, we find that centralized influence is desirable in situations where a crowd is predisposed to overestimation bias and/or have a high likelihood of committing egregious errors. By adopting a framework that integrates both the structure of social influence and the estimation context, we bring the previously conflicting results under one theoretical framework and clarify the effects of influence centralization on the quality of crowd wisdom.

摘要:关于是否,如果是,在什么条件下,群体表现出“群体智慧”的问题已经激发了许多学科的大量研究,包括管理和组织科学、心理学、社会学、复杂系统和计算机科学。以前对这些问题的大量研究都集中在调查社会影响力在提升群体智慧中的作用,或者相反,引导群体误入歧途。具体来说,许多以前的研究都试图推断社会影响网络属性(如影响集中)的重要性来解释集体估计的准确性。在本文中,我们认为这种方法是有限的,并可能导致不一致的结论。基于我们的理论分析、数值模拟以及对以前发表的四个实验的重新分析(包括总共4002个人参与者,组织在131个独立的小组中) ,我们证明了群体在评估任务中的智慧取决于以下两个因素之间的相互作用: (i)社会影响网络的集中性,和(ii)评估环境的特征——即初始(预影响)评估的分布。具体来说,我们发现,在人群倾向于过高估计偏差和 / 或犯下严重错误的可能性很高的情况下,集中影响是可取的。通过采用一个整合了社会影响力结构和评价语境的框架,我们把以前相互冲突的结果放在一个理论框架下,阐明了影响力集中对群体智慧质量的影响。



实验耦合 logistic 映射中

的分岔和滞后现象


原文标题:

Observation of bifurcations and hysteresis in experimentally coupled logistic maps

地址:

https://arxiv.org/abs/2006.11378

作者:

Caracé Gutiérrez,Cecilia Cabeza,Nicolás Rubido


Abstract:Initially, the logistic map became popular as a simplified model for population growth. In spite of its apparent simplicity, as the population growth-rate is increased the map exhibits a broad range of dynamics, which include bifurcation cascades going from periodic to chaotic solutions. Studying coupled maps allows to identify other qualitative changes in the collective dynamics, such as pattern formations or hysteresis. Particularly, hysteresis is the appearance of different attracting sets, a set when the control parameter is increased and another set when it is decreased -- a multi-stable region. In this work, we present an experimental study on the bifurcations and hysteresis of nearly identical, coupled, logistic maps. Our logistic maps are an electronic system that has a discrete-time evolution with a high signal-to-noise ratio (∼106), resulting in simple, precise, and reliable experimental manipulations, which include the design of a modifiable diffusive coupling configuration circuit. We find that the characterisations of the isolated and coupled logistic-maps' dynamics agrees excellently with the theoretical and numerical predictions (such as the critical bifurcation points and Feigenbaum's bifurcation velocity). Here, we report multi-stable regions appearing robustly across configurations, even though our configurations had parameter mismatch (which we measure directly from the components of the circuit and also infer from the resultant dynamics for each map) and were unavoidably affected by electronic noise.

摘要:最初,逻辑地图作为人口增长的简化模型而流行起来。尽管它看起来简单,但是随着人口增长率的增加,这个映射展示了一个广泛的动力学范围,其中包括从周期解到混沌解的分叉级联。研究耦合映射允许识别集体动力学的其他定性变化,如图案形成或滞后。特别地,滞后是指不同吸引集的出现,控制参数增加时出现的滞后现象,控制参数减少时出现的滞后现象——多稳定区域。在这项工作中,我们提出了一个实验研究分岔和滞后的几乎相同,耦合,逻辑斯谛映射。我们的逻辑地图是一个电子系统,具有离散时间演变的高信噪比(∼106), 设计了一种可变扩散耦合结构电路,实现了简单、精确、可靠的实验操作。我们发现孤立和耦合 logistic 映射的动力学特征与理论和数值预测(如临界分岔点和 Feigenbaum 分岔速度)非常吻合。在这里,我们报告了多稳定区域在配置上表现强劲,尽管我们的配置有参数不匹配(我们直接从电路的元件测量,并从每个映射的结果动力学推断) ,并且不可避免地受到电子噪声的影响。



在网络化动态系统中识别

有助于产生极端事件的边界


原文标题:

Identifying edges that facilitate the generation of extreme events in networked dynamical systems

地址:

https://arxiv.org/abs/2006.11410

作者:

Timo Bröhl,Klaus Lehnertz


Abstract:The collective dynamics of complex networks of FitzHugh-Nagumo units exhibits rare and recurrent events of high amplitude (extreme events) that are preceded by so-called proto-events during which a certain fraction of the units become excited. Although it is well known that a sufficiently large fraction of excited units is required to turn a proto-event into an extreme event, it is not yet clear how the other units are being recruited into the final generation of an extreme event. Addressing this question and mimicking typical experimental situations, we investigate the centrality of edges in time-dependent interaction networks. We derived these networks from time series of the units' dynamics employing a widely used bivariate analysis technique. Using our recently proposed edge centrality concepts together with an edge-based network decomposition technique, we observe that the recruitment is primarily facilitated by sets of certain edges that have no equivalent in the underlying topology. Our finding might aid to improve the understanding of generation of extreme events in natural networked dynamical systems.

摘要:Fitzhugh-nagumo 单元复杂网络的集体动力学表现出罕见的高振幅反复事件(极端事件) ,这些事件之前发生所谓的原始事件,在此期间某些单元被激发。虽然众所周知,要把一个原始事件变成一个极端事件,需要一小部分激发单位的足够大,但是其他单位是如何被招募到一个极端事件的最后一代中还不清楚。针对这个问题,模拟典型的实验情况,我们研究了依赖时间的交互网络中边缘的中心性。我们利用广泛使用的双变量分析技术,从单位动态的时间序列中推导出这些网络。使用我们最近提出的边缘中心性概念和基于边缘的网络分解技术,我们观察到招募主要是由某些边的集合促成的,这些边在底层拓扑中没有等价物。我们的发现可能有助于提高对自然网络动力系统中极端事件产生的理解。



进化油藏计算网络中的功能差异


原文标题:

Functional differentiations in evolutionary reservoir computing networks

地址:

http://arxiv.org/abs/2006.11507

作者:

Yutaka Yamaguti,Ichiro Tsuda


Abstract:We propose an extended reservoir computer that shows the functional differentiation of neurons. The reservoir computer is developed to enable changing of the internal reservoir using evolutionary dynamics, and we call it an evolutionary reservoir computer. To develop neuronal units to show specificity, depending on the input information, the internal dynamics should be controlled to produce contracting dynamics after expanding dynamics. Expanding dynamics magnifies the difference of input information, while contracting dynamics contributes to forming clusters of input information, thereby producing multiple attractors. The simultaneous appearance of both dynamics indicates the existence of chaos. In contrast, sequential appearance of these dynamics during finite time intervals may induce functional differentiations. In this paper, we show how specific neuronal units are yielded in the evolutionary reservoir computer.

摘要:我们提出了一个扩展的储备计算机,显示神经元的功能分化。油藏计算机是利用演化动力学来实现油藏内部变化的,我们称之为演化油藏计算机。为了发展神经元单位以显示特异性,根据输入信息,控制内部动力学,在扩展动力学后产生收缩动力学。扩展的动力学放大了输入信息的差异,而收缩的动力学有助于形成输入信息的集群,从而产生多个吸引子。这两种动力学的同时出现表明混沌的存在。相反,在有限的时间间隔内,这些动力学的连续出现可能诱导功能分化。在这篇文章中,我们展示了特定的神经元单位是如何在进化储备计算机中产生的。



社会信任网络中的意见最大


原文标题:

Opinion Maximization in Social Trust Networks

地址:

https://arxiv.org/abs/2006.10961

作者:

Pinghua Xu,Wenbin Hu,Jia Wu,Weiwei Liu


Abstract:Social media sites are now becoming very important platforms for product promotion or marketing campaigns. Therefore, there is broad interest in determining ways to guide a site to react more positively to a product with a limited budget. However, the practical significance of the existing studies on this subject is limited for two reasons. First, most studies have investigated the issue in oversimplified networks in which several important network characteristics are ignored. Second, the opinions of individuals are modeled as bipartite states(e.g., support or not) in numerous studies, however, this setting is too strict for many real scenarios. In this study, we focus on social trust networks(STNs), which have the significant characteristics ignored in the previous studies. We generalized a famed continuous-valued opinion dynamics model for STNs, which is more consistent with real scenarios. We subsequently formalized two novel problems for solving the issue in STNs. Moreover, we developed two matrix-based methods for these two problems and experiments on real-world datasets to demonstrate the practical utility of our methods.

摘要:社交媒体网站现在正成为产品推广或营销活动的重要平台。因此,有广泛的兴趣,确定如何指导网站反应更积极的产品与有限的预算。然而,由于两个方面的原因,现有研究的现实意义有限。首先,大多数研究都是在过分简化的网络中进行研究,忽略了一些重要的网络特征。其次,在许多研究中,个人的意见被建模为两部分的状态(例如,支持与否) ,然而,这种设置对于许多真实的场景来说过于严格。本研究以社会信任网络为研究对象,以往的研究忽略了其重要特征。我们推广了一个著名的连续值观点动力学模型,该模型更符合实际场景。随后,我们将两个新问题正式化,以解决在 stn 中的问题。此外,我们还针对这两个问题开发了两种基于矩阵的方法,并在实际数据集上进行了实验,以证明我们的方法的实用性。



监测新型冠状病毒肺炎

流感大流行下的全球情绪


原文标题:

SenWave: Monitoring the Global Sentiments under the COVID-19 Pandemic

地址:

https://arxiv.org/abs/2006.10842

作者:

Qiang Yang,Hind Alamro,Somayah Albaradei,Adil Salhi,Xiaoting Lv,Changsheng Ma,Manal Alshehri,Inji Jaber,Faroug Tifratene,Wei Wang,Takashi Gojobori,Carlos M. Duarte,Xin Gao,Xiangliang Zhang


Abstract:Since the first alert launched by the World Health Organization (5 January, 2020), COVID-19 has been spreading out to over 180 countries and territories. As of June 18, 2020, in total, there are now over 8,400,000 cases and over 450,000 related deaths. This causes massive losses in the economy and jobs globally and confining about 58% of the global population. In this paper, we introduce SenWave, a novel sentimental analysis work using 105+ million collected tweets and Weibo messages to evaluate the global rise and falls of sentiments during the COVID-19 pandemic. To make a fine-grained analysis on the feeling when we face this global health crisis, we annotate 10K tweets in English and 10K tweets in Arabic in 10 categories, including optimistic, thankful, empathetic, pessimistic, anxious, sad, annoyed, denial, official report, and joking. We then utilize an integrated transformer framework, called simpletransformer, to conduct multi-label sentimental classification by fine-tuning the pre-trained language model on the labeled data. Meanwhile, in order for a more complete analysis, we also translate the annotated English tweets into different languages (Spanish, Italian, and French) to generated training data for building sentiment analysis models for these languages. SenWave thus reveals the sentiment of global conversation in six different languages on COVID-19 (covering English, Spanish, French, Italian, Arabic and Chinese), followed the spread of the epidemic. The conversation showed a remarkably similar pattern of rapid rise and slow decline over time across all nations, as well as on special topics like the herd immunity strategies, to which the global conversation reacts strongly negatively. Overall, SenWave shows that optimistic and positive sentiments increased over time, foretelling a desire to seek, together, a reset for an improved COVID-19 world.

摘要:自从世界卫生组织发布第一个预警(2020年1月5日)以来,新型冠状病毒肺炎已经向180多个国家和地区传播。截至2020年6月18日,总共有超过8,400,000个病例和超过450,000个相关死亡。这导致全球经济和就业机会大量减少,限制了全球约58% 的人口。在本文中,我们介绍 SenWave,一个新颖的情感分析工作,使用收集的1.05亿条推特和微博信息来评估全球在新型冠状病毒肺炎流感大流行期间情感的兴衰。为了对我们面对这场全球健康危机时的感受进行细致的分析,我们将10K 条推文用英语注释,10K 条推文用阿拉伯语注释,分为10个类别,包括乐观、感恩、同情、悲观、焦虑、悲伤、烦恼、否认、官方报告和开玩笑。然后,我们利用一个集成的变换器框架,称为简单变换器,进行多标签情感分类,通过微调前训练语言模型的标记数据。与此同时,为了进行更全面的分析,我们还将带注释的英文 tweets 翻译成不同的语言(西班牙语、意大利语和法语) ,以生成用于构建这些语言的情感分析模型的培训数据。因此,SenWave 揭示了流行病传播之后,全球对话在新型冠状病毒肺炎上以6种不同语言(包括英语、西班牙语、法语、意大利语、阿拉伯语和中文)进行的情绪。随着时间的推移,在所有国家,以及在诸如群体免疫策略这样的特殊话题上,全球对话都会产生强烈的负面反应,这种对话显示出一种非常相似的快速上升和缓慢下降的模式。总的来说,SenWave 显示乐观和积极的情绪随着时间的推移而增长,预示着一种共同寻求改善新型冠状病毒肺炎世界的愿望。



基于资源分配的超边界预测


原文标题:

HPRA: Hyperedge Prediction using Resource Allocation

地址:

https://arxiv.org/abs/2006.10842

作者:

Tarun Kumar,K Darwin,Srinivasan Parthasarathy,Balaraman Ravindran


Abstract:Many real-world systems involve higher-order interactions and thus demand complex models such as hypergraphs. For instance, a research article could have multiple collaborating authors, and therefore the co-authorship network is best represented as a hypergraph. In this work, we focus on the problem of hyperedge prediction. This problem has immense applications in multiple domains, such as predicting new collaborations in social networks, discovering new chemical reactions in metabolic networks, etc. Despite having significant importance, the problem of hyperedge prediction hasn't received adequate attention, mainly because of its inherent complexity. In a graph withn nodes the number of potential edges is O(n2), whereas in a hypergraph, the number of potential hyperedges is O(2n). To avoid searching through such a huge space, current methods restrain the original problem in the following two ways. One class of algorithms assume the hypergraphs to be k-uniform. However, many real-world systems are not confined only to have interactions involving k components. Thus, these algorithms are not suitable for many real-world applications. The second class of algorithms requires a candidate set of hyperedges from which the potential hyperedges are chosen. In the absence of domain knowledge, the candidate set can have O(2n) possible hyperedges, which makes this problem intractable. We propose HPRA - Hyperedge Prediction using Resource Allocation, the first of its kind algorithm, which overcomes these issues and predicts hyperedges of any cardinality without using any candidate hyperedge set. HPRA is a similarity-based method working on the principles of the resource allocation process. In addition to recovering missing hyperedges, we demonstrate that HPRA can predict future hyperedges in a wide range of hypergraphs.

摘要:许多现实世界的系统涉及到高阶的相互作用,因此需要复杂的模型,如超图。例如,一篇研究论文可能有多个合作作者,因此合作作者网络最好用超图来表示。本文主要研究超边界预测问题。这个问题在多个领域有着广泛的应用,例如在社交网络中预测新的合作,在新陈代谢网络中发现新的化学反应等。超边缘预测问题虽然具有重要的意义,但由于其固有的复杂性,一直没有得到足够的重视。在一个带有n 节点的位势边的数目是O(n2), 然而在超图中,势超边的个数是O(2n). 为了避免在这样一个巨大的空间中进行搜索,现有的方法主要从以下两个方面来抑制原问题。一类算法假设超图是k- 统一。然而,许多现实世界的系统并不只局限于包括k 组件。因此,这些算法不适用于许多现实世界的应用。第二类算法需要一组候选超边,从中选择潜在的超边。在没有领域知识的情况下,候选集可以具有O(2n) 可能是超边,这使得这个问题很棘手。本文提出了一种基于资源分配的 HPRA-超边预测算法,该算法克服了这些问题,不需要使用任何候选超边集就可以预测任意基数的超边。Hpra 是一种基于相似性的方法,它遵循资源分配过程的原则。除了恢复丢失的超边外,我们证明了 HPRA 能够在广泛的超图中预测未来的超边。



青少年幸福感测量:

幼稚数字痕迹与调查数据的对应


原文标题:

Measuring Adolescents' Well-being: Correspondence of Naive Digital Traces to Survey Data

地址:

https://arxiv.org/abs/2006.11176

作者:

Elizaveta Sivak,Ivan Smirnov


Abstract:Digital traces are often used as a substitute for survey data. However, it is unclear whether and how digital traces actually correspond to the survey-based traits they purport to measure. This paper examines correlations between self-reports and digital trace proxies of depression, anxiety, mood, social integration and sleep among high school students. The study is based on a small but rich multilayer data set (N = 144). The data set contains mood and sleep measures, assessed daily over a 4-month period, along with survey measures at two points in time and information about online activity from VK, the most popular social networking site in Russia. Our analysis indicates that 1) the sentiments expressed in social media posts are correlated with depression; namely, adolescents with more severe symptoms of depression write more negative posts, 2) late-night posting indicates less sleep and poorer sleep quality, and 3) students who were nominated less often as somebody's friend in the survey have fewer friends on VK and their posts receive fewer "likes." However, these correlations are generally weak. These results demonstrate that digital traces can serve as useful supplements to, rather than substitutes for, survey data in studies on adolescents' well-being. These estimates of correlations between survey and digital trace data could provide useful guidelines for future research on the topic.

摘要:数字痕迹经常被用作调查数据的替代品。然而,目前还不清楚数字痕迹是否以及如何与他们声称要测量的基于调查的特征相对应。本文研究了高中生自我报告与抑郁、焦虑、情绪、社会整合和睡眠的数字痕迹代理之间的相关性。这项研究是基于一个小而丰富的多层数据集(n = 144)。这些数据包括情绪和睡眠测量数据,在4个月的时间里每天进行评估,同时还包括两个时间点的调查测量数据,以及俄罗斯最受欢迎的社交网站 VK 提供的有关在线活动的信息。我们的分析表明: 1)社交媒体帖子中表达的情绪与抑郁症有关; 也就是说,抑郁症症状更严重的青少年写的负面帖子更多; 2)深夜发帖意味着睡眠更少、睡眠质量更差; 3)在调查中被提名为朋友的学生在 VK 上的朋友更少,他们的帖子得到的“赞”也更少 然而,这些相关性普遍较弱。这些结果表明,在青少年幸福研究中,数字痕迹可以作为调查数据的有用补充,而不是替代。这些关于调查和数字痕迹数据之间相关性的估计可以为今后关于这一主题的研究提供有用的指导。



自适应扩散下的多观测谣言源检测


原文标题:

Rumor source detection with multiple observations under adaptive diffusions

地址:

https://arxiv.org/abs/2006.11176

作者:

Miklos Z. Racz,Jacob Richey


Abstract:Recent work, motivated by anonymous messaging platforms, has introduced adaptive diffusion protocols which can obfuscate the source of a rumor: a "snapshot adversary" with access to the subgraph of "infected" nodes can do no better than randomly guessing the entity of the source node. What happens if the adversary has access to multiple independent snapshots? We study this question when the underlying graph is the infinited-regular tree. We show that (1) a weak form of source obfuscation is still possible in the case of two independent snapshots, but (2) already with three observations there is a simple algorithm that finds the rumor source with constant probability, regardless of the adaptive diffusion protocol. We also characterize the tradeoff between local spreading and source obfuscation for adaptive diffusion protocols (under a single snapshot). These results raise questions about the robustness of anonymity guarantees when spreading information in social networks.

摘要:最近,在匿名消息传递平台的推动下,引入了自适应扩散协议,这种协议可以模糊谣言的来源: 有权访问“被感染”节点子图的“对手快照”只能随机猜测源节点的实体。如果对手可以访问多个独立的快照会发生什么?当底图是无穷大时,我们研究这个问题d- 普通树。我们证明: (1)在两个独立的快照情况下,仍然可能存在一种弱形式的源混淆,但是(2)已经有了三个观察值,有一个简单的算法,不管自适应扩散协议如何,都可以找到具有常数概率的谣言源。我们还刻画了自适应扩散协议在本地扩散和源模糊之间的权衡(在单个快照下)。这些结果提出了关于在社会网络中传播信息时匿名保证的稳健性的问题。



心理物理学: 

两个耦合的正方形脉冲神经元

在临界状态下具有巨大的动态范围


原文标题:

Physics of Psychophysics: two coupled square lattices of spiking neurons have huge dynamic range at criticality

地址:

https://arxiv.org/abs/2006.11254

作者:

Emilio F. Galera,Osame Kinouchi


Abstract:Psychophysics try to relate physical input magnitudes to psychological or neural correlates. Microscopic models to account for macroscopic psychophysical laws, in the sense of statistical physics, are an almost unexplored area. Here we examine a sensory epithelium composed of two connected square lattices of stochastic integrate-and-fire cells. With one square lattice we obtain a Stevens's lawρ∝hm with Stevens's exponent m=0.254 and a sigmoidal saturation, where ρ is the neuronal network activity and h is the input intensity (external field). We relate Stevens's power law exponent with the field critical exponent as m=1/δh=β/σ. We also show that this system pertains to the Directed Percolation (DP) universality class (or perhaps the Compact-DP class). With stacked two layers of square lattices, and a fraction of connectivity between the first and second layer, we obtain at the output layer ρ2∝hm2, with m2=0.08≈m2, which corresponds to a huge dynamic range. This enhancement of the dynamic range only occurs when the layers are close to their critical point.

摘要:心理物理学试图将物理输入量与心理或神经相关联。用微观模型来解释宏观的心理物理定律,在统计物理学的意义上,是一个几乎未被探索的领域。在这里,我们检查一个感觉上皮组成的两个连接的方格随机积分和火细胞。对于一个正方形点阵,我们得到了一个斯蒂文斯定律ρ∝hm 史蒂文斯的指数m=0.254 和相似的饱和度,其中ρ 是是神经元网络活动,h 是 输入强度 ,我们将斯蒂文斯的幂律指数与场临界指数关系如下:m=1/δh=β/σ.我们还证明了该系统属于定向 Percolation (DP)普适性类(或者可能属于 compact-DP 类)。通过叠加两层正方形晶格,以及第一层和第二层之间连通性的一小部分,我们可以在输出层获得ρ2∝hm2, m2=0.08≈m2,相当于一个巨大的动态范围。这种动态范围的增强只发生在层接近其临界点的时候。



英国新型冠状病毒肺炎禁闭: 

对空气污染有什么影响


原文标题:

UK COVID-19 Lockdown: What are the impacts on air pollution

地址:

https://arxiv.org/abs/2006.10785

作者:

J. E. Higham,M. A. Green,C. Acosta Ramirez


Abstract:A country-wide `lock-down' imposed on the 23red March 2020 in the UK had a significant impact on the UK's anthropogenic movements. The closure of work-places and restrictions imposed on visiting friends and family has radically reduced the amount of traffic on the roads. In this short communication, we use data from UK air-quality sensors to quantify air pollution trends pre- and post-lock-down. While we detect large falls in nitrogen dioxide at levels not seen over the last decade, trends in other pollutants were mixed especially when compared to historical data. It suggests that the implication that lock-down was beneficial for the environment was not so obvious.

摘要:2020年3月23日,英国实施了全国范围的“封锁” ,对英国的人为活动产生了重大影响。工作场所的关闭以及对探望朋友和家人的限制大大减少了道路上的交通量。在这个简短的交流中,我们使用来自英国空气质量传感器的数据来量化封锁前后的空气污染趋势。虽然我们检测到二氧化氮的水平大幅下降,但是其他污染物的趋势却好坏参半,尤其是与历史数据相比。这表明,封锁有利于环境的含义并不是那么明显。



几何,推理,复杂性和民主


原文标题:

Geometry, Inference, Complexity, and Democracy

地址:

https://arxiv.org/abs/2006.10879

作者:

Jordan S. Ellenberg


Abstract:Decisions about how the population of the United States should be divided into legislative districts have powerful and not fully understood effects on the outcomes of elections. The problem of understanding what we might mean by "fair districting" intertwines mathematical, political, and legal reasoning; but only in recent years has the academic mathematical community gotten directly involved in the process. I'll report on recent progress in this area, how newly developed mathematical tools have affected real political decisions, and what remains to be done. This survey represents the content of a lecture presented by the author in the Current Events Bulletin session of the Joint Mathematics Meetings in January 2020.

摘要:关于如何将美国人口划分为立法区的决定对选举结果产生了强大而又未被充分理解的影响。理解我们所说的“公平分区”是什么意思的问题将数学、政治和法律推理联系在一起; 但是直到最近几年,学术数学界才直接参与到这个过程中来。我将报告这一领域的最新进展,新开发的数学工具如何影响真正的政治决策,以及还需要做什么。本调查是作者在2020年1月数学联席会议的时事简报会上发表的一次演讲的内容。



使用概率细胞自动机研究

计算模型新型冠状病毒肺炎流行病


原文标题:

Computational model on COVID-19 Pandemic using Probabilistic Cellular Automata

地址:

https://arxiv.org/abs/2006.11270

作者:

Sayantari Ghosh,Saumik Bhattacharya


Abstract:Coronavirus disease (COVID-19) which is caused by SARS-COV2 has become a pandemic. This disease is highly infectious and potentially fatal, causing a global public health concern. To contain the spread of COVID-19, governments are adopting nationwide interventions, like lockdown, containment and quarantine, restrictions on travel, cancelling social events and extensive testing. To understand the effects of these measures on the control of the epidemic in a data-driven manner, we propose a probabilistic cellular automata (PCA) based modified SEIQR model. The transitions associated with the model is driven by data available on chronology, symptoms, pathogenesis and transmissivity of the virus. By arguing that the lattice-based model captures the features of the dynamics along with the existing fluctuations, we perform rigorous computational analyses of the model to take into account of the spatial dynamics of social distancing measures imposed on the people. Considering the probabilistic behavioural aspects associated with mitigation strategies, we study the model considering factors like population density and testing efficiency. Using the model, we focus on the variability of epidemic dynamics data for different countries and point out the reasons behind these contrasting observations. To the best of our knowledge, this is the first attempt to model COVID-19 spread using PCA that gives us both spatial and temporal variations of the infection spread with the insight about the contributions of different infection parameters.

摘要:由 SARS-COV2引起的冠状病毒病(新型冠状病毒肺炎)已经成为一种流行病。这种疾病具有高度传染性,可能致命,引起全球公共卫生关注。为了遏制新型冠状病毒肺炎的蔓延,各国政府正在采取全国性的干预措施,如封锁、隔离和隔离、限制旅行、取消社会活动和广泛的检测。为了以数据驱动的方式理解这些措施对流行病控制的影响,我们提出了一种基于概率元胞自动机(PCA)的改进 SEIQR 模型。与该模型相关的转变是由关于病毒的年代学、症状、发病机制和传播率的数据驱动的。通过论证基于格子的模型捕获了动力学的特征以及存在的波动,我们对模型进行了严格的计算分析,以考虑强加在人们身上的社会距离措施的空间动力学。考虑到与减灾策略相关的概率行为方面,我们研究了考虑种群密度和测试效率等因素的模型。利用该模型,我们重点关注不同国家的流行病动态数据的可变性,并指出这些对比观察背后的原因。据我们所知,这是第一次尝试使用 PCA 模型来模拟新型冠状病毒肺炎传播,该模型通过洞察不同感染参数的作用,为我们提供了感染传播的时空变化。


来源:集智斑图
编辑:王建萍



近距离感染传播的蒙特卡罗模拟研究 | 网络科学论文速递39篇-集智俱乐部


集智俱乐部QQ群|877391004

商务合作及投稿转载|swarma@swarma.org

◆ ◆ 

搜索公众号:集智俱乐部


加入“没有围墙的研究所”

近距离感染传播的蒙特卡罗模拟研究 | 网络科学论文速递39篇-集智俱乐部

让苹果砸得更猛烈些吧!