Shimizu, SeishiMatubayasi, Nobuyuki
14页查看更多>>摘要：Interactions in complex solutions that consist of multiple components can be quantified via number correlations observed within an isochoric subsystem. The fluctuation solution theory carries out a conversion between experimental data (usually measured under isobaric conditions) and the isochoric number correlations through cumbersome thermodynamic variable transformations. In contrast, we have recently demonstrated heuristically that direct transformation of statistical variables (i.e., those variables fluctuating in statistical ensembles such as volume and particle numbers) can lead to equivalent results via simple algebra. This paper reveals the geometrical basis of fluctuation and the invariants underlying the equivalence between thermodynamic and statistical variable transformations. Based on the quasi-thermodynamic fluctuation theory and the postulate that concentration and its fluctuation are invariant under ensemble transformation, we show that the thermodynamic and statistical variable transformations correspond to the change of basis on the Hessian matrix and the vectors whose elements are the deviations of statistical variables from their mean values, respectively, under which the quadratic form of fluctuation is invariant. Statistical variable transformation can also be used in cases when a set of experimental data do not belong to the same ensemble. When combined with the order-of-magnitude analysis, our formalism shows that the quasi-thermodynamic formalism of fluctuation at the thermodynamic limit is valid only for extensive variables and cannot be applied to intensive variables. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:
NSTL
Elsevier
Costa, Luciano da F.Tokuda, Eric K.Comin, Cesar H.
17页查看更多>>摘要：Hierarchical agglomerative methods stand out as particularly effective and popular approaches for clustering data. Yet, these methods have not been systematically compared regarding the important issue of false positives while searching for clusters. A model of clusters involving a higher density nucleus surrounded by a transition, followed by outliers is adopted as a means to quantify the relevance of the obtained clusters and address the problem of false positives. Six traditional methodologies, namely the single, average, median, complete, centroid and Ward's linkage criteria are compared with respect to the adopted model. Unimodal and bimodal datasets obeying uniform, gaussian, exponential and power-law distributions are considered for this comparison. The obtained results include the verification that many methods detect two clusters in unimodal data. The single-linkage method was found to be more resilient to false positives. Also, several methods detected clusters not corresponding directly to the nucleus. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:- NSTL
- Elsevier
Wang, JianweiWang, SiyuanWang, Ziwei
13页查看更多>>摘要：Different from the previous research framework of cascading failure driven by intentional attack or random failure, this paper considers the occurrence of cascading failure from a new perspective, i.e., the spontaneous phenomenon of cascading failure. When the network changes from the low peak period to the high peak period, the global distribution of load changes, which leads to the cascading failure of the network. This phenomenon is called the spontaneous phenomenon of cascading failure. We introduce the concept of reachable region and construct a new cascading failure model, which mainly focus on how the dynamic changes of reachable area drive the dynamic behavior of cascade failures. Through simulation on two infrastructure networks, we found that: (1) The size of reachable area is positively correlated with network robustness. The larger the reachable area is, the smaller the load fluctuation of the whole network is, and the cascading failures are more easily alleviated and the network robustness is higher. But when the edge load capacity increases, the robustness of the network is not necessarily improved, which indicates the existence of capacity paradox. (2) The size of reachable area is negatively correlated with network capacity redundancy. The larger the reachable area is, the lower the capacity redundancy of the whole network will be and the less network resources will be wasted. (3) Combining with the network topology and the phenomenon of "key edge" we find that the edge with less betweenness centrality usually needs to invest higher resource protection. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:- NSTL
- Elsevier
Sudakov, IvanVakulenko, Sergey A.Bruun, John T.
12页查看更多>>摘要：Species extinction is a core process that affects the diversity of life on Earth. Competition between species in a population is considered by ecological niche-based theories as a key factor leading to different severity of species extinctions. There are population dynamic models that describe a simple and easily understandable mechanism for resource competition. However, these models cannot efficiently characterize and quantify new emergent extinctions in a large population appearing due to environmental forcing. To address this issue we develop a stochastic physics-inspired approach to analyze how environmental forcing influences the severity of species extinctions in such models. This approach is based on the large deviations theory of stochastic processes (the Freidlin-Wentzell theory). We show that there are three possible fundamentally different scenarios of extinctions, which we call catastrophic extinctions, asymmetric ones, and extinctions with exponentially small probabilities. The realization of those scenarios depends on environmental noise properties and the boundaries of niches, which define the domain, where species survive. Furthermore, we describe a hysteresis effect in species extinction showing that fluctuations can lead to dramatic consequences even if an averaged resource supply is sufficient to support population survival. Our stochastic physics-inspired approach generalizes niche theory by accounting for environmental forcing and will be useful to establish, with available data, which environmental perturbations may induce extinctions. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:- NSTL
- Elsevier
Xu, GenjiuYang, YimeiSun, Hao
11页查看更多>>摘要：We investigate the evolution of cooperation with a bilaterally-agree partner switching mechanism in which two players rather than one determine whether to break a link. In this mechanism, we define an edge game to describe this bilateral consultation process. Through analyzing the Pure Nash Equilibrium of this game, we find that defectors intend to keep in touch with cooperators while cooperators prefer to break links with defectors in most cases. However, introducing such a mechanism results in that a defector would transfer part of his payoff to his cooperative neighbors conditionally, which maintains the link between cooperators and defectors. Besides, this transfer narrows the payoff gap between the two types of players and therefore promotes the propagation of cooperation. Our results highlight the importance of consultation on the realization of global cooperation. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:- NSTL
- Elsevier
Ghosh, AritraBandyopadhyay, MalayBhamidipati, Chandrasekhar
12页查看更多>>摘要：We develop a geometric formalism suited for describing the quantum thermodynamics of a certain class of nanoscale systems (whose density matrix is expressible in the McLennan-Zubarev form) at any arbitrary non-equilibrium steady state. It is shown that the non-equilibrium steady states are points on control parameter spaces which are in a sense generated by the steady state Massieu-Planck function. By suitably altering the system's boundary conditions, it is possible to take the system from one steady state to another. We provide a contact Hamiltonian description of such transformations and show that moving along the geodesics of the friction tensor results in a minimum increase of the free entropy along the transformation. The control parameter space is shown to be equipped with a natural Riemannian metric that is compatible with the contact structure of the quantum thermodynamic phase space which when expressed in a local coordinate chart, coincides with the Schlogl metric. Finally, we show that this metric is conformally related to other thermodynamic Hessian metrics which might be written on control parameter spaces. This provides various alternate ways of computing the Schlogl metric which is known to be equivalent to the Fisher information matrix. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:- NSTL
- Elsevier
Zheng, Yi-DanMao, ZhuZhou, Bin
9页查看更多>>摘要：We theoretically propose a dense coding scheme based on an infinite spin-1/2 Ising-XXZ diamond chain, where the Heisenberg spins dimer can be considered as a quantum channel. Using the transfer-matrix approach, we can obtain the analytical expression of the optimal dense coding capacity chi. The effects of anisotropy, external magnetic field, and temperature on chi in the diamond-like chain are discussed, respectively. It is found that chi is decayed with increasing the temperature, while the valid dense coding (chi > 1) can be carried out by tuning the anisotropy parameter. Additionally, a certain external magnetic field can stimulate the enhancement of dense coding capacity. In an infinite spin-1/2 Ising-XXZ diamond chain, it has been shown that there exist two kinds of quantum phase transitions (QPTs) in zero-temperature phase diagram, i.e., one is that the ground state of system changes from the unentangled ferrimagnetic state to the entangled frustrated state and the other is from the entangled frustrated state to the unentangled ferromagnetic state. Here, we propose that optimal dense coding capacity chi can be regarded as a new detector of QPTs in this diamond-like chain, and the relationship between chi and QPTs is well established. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:- NSTL
- Elsevier
Huang, HaichaoChen, JingyaSun, RuiWang, Shuang...
15页查看更多>>摘要：Traffic flow decomposition is an alternative method to explore the composition of traffic flow and improve prediction accuracy. However, most of them suffer from the inability to fully utilize the character of traffic data. This paper presents a novel framework for traffic flow decomposition and modeling named Time Series Decomposition (TSD). The traffic flow is adaptively decomposed into periodic component, residual component and volatile component which are modeled respectively. Empirical Mode Decomposition (EMD) is applied to extract the intrinsic mode functions (IMFs) of traffic flow, the periodic patterns are intuitively presented via Hilbert transform in terms of frequencies. Then the periodic component can be described as a Fourier series based on obtained frequencies. Meanwhile, the residual component is presented by IMF with the lowest frequency. The remaining part is the volatile component modeled by supervised learning. The proposed hybrid model is evaluated on the real-world dataset and compared with classical baseline models. The results demonstrate that TSD can unearth the underlying periodic patterns and provide an explicable composition of the traffic flow. Furthermore, the volatile component ensures the accuracy of single-step prediction while periodic and residual components show promising abilities in improving the multi-step prediction accuracy of short-term traffic flow. (C) 2021 The Author(s). Published by Elsevier B.V.
原文链接:- NSTL
- Elsevier
Venditti, ClaudiaAdrover, AlessandraGiona, Massimiliano
18页查看更多>>摘要：The motion of non-interacting Brownian particles in the washboard potential is investigated in inertial regimes, when the overdamped approximation does not yield accurate predictions. The analysis is based on homogenization methods, deriving closed-form expressions for the long-term transport properties, i.e. effective velocity and diffusion coefficient. Different reduced models of increasing complexity, improving the overdamped approximation, are developed starting from the basic assumption that the velocity variable can be split into an "almost" deterministic and a fully stochastic contribution. The almost deterministic velocity term can be estimated from a fully deterministic or from a stochastic slow inertial manifold. The latter approach provides accurate predictions for all the asymptotic transport properties. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:- NSTL
- Elsevier
Li, YumengZheng, LeiLi, YouqiZhou, Jingsai...
7页查看更多>>摘要：The evolutionary ultimatum game is a powerful paradigm to study the evolution of fairness. Most studies to date assume that a player adopts the same strategy against all his/her opponents. Apart from these works, there are also works exploring the evolution of fairness when various psychological and social factors influence strategies, but celebrity has never been considered. In this paper, we introduce the effect of celebrity, under which a player behaves more generous or stingier when faces different opponents. The celebrity of individuals in a social network is defined as their degree, and ordinary people have small degrees while celebrities have large degrees. The result shows that if ordinary people tend to be more generous to celebrities and celebrities are stingier to the ordinary, fairness will be enhanced first and gradually evolves to an over-fair level. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:- NSTL
- Elsevier
