Peng, GuanghanJia, TetiKuang, HuaTan, Huili...
14页查看更多>>摘要：A novel lattice hydrodynamic model is proposed based on the delayed effect of synergistic information transmission involving density and flux. The stability condition of the novel model is further analyzed theoretically via the linear analysis. Through nonlinear analysis, the modified Korteweg-de Vries (mKdV) equation near the critical point is obtained. The changing trends of density wave, flux and energy consumption are investigated when a small perturbation is intervened into the uniform traffic flow. The results show that the delayed effect of collaborative information transmission can effectively suppress traffic congestion, reduce energy consumption, and improve the stability of the traffic system. Theoretical analysis and simulation results verify the feasibility and validity of the delayed effect of collaborative information transmission on the improvement of traffic flow. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:
NSTL
Elsevier
Jing, WenjunLi, YiZhang, XiaoqinZhang, Juping...
10页查看更多>>摘要：The heterogeneity in edge weights plays a crucial role in the spread of a rumor on networks. To investigate the effects of weight distribution on a rumor spreading, we employ an ISR pairwise model on weighted regular random networks in this paper. The basic reproductive ratio of this model is derived, and it indicates that the heterogeneity in transmission rate leads to a fall in the basic reproductive ratio when the average transmission rate is fixed. Besides, by assuming that the transmission rate is a linear function of the edge weight, numerical simulation results of the model on networks with a bimodal weight distribution show that weight heterogeneity has a complex impact on the dynamics of a rumor. When we fix the proportions of two weights but vary their values to keep a constant average weight, increasing the heterogeneity in weight distribution slows down the initial growth rate, the final size and the maximum influence of a rumor, but increases the duration for rumor spreading. However, if we change both the values and proportions of two weights, only the mean and variance of the weight distribution are not able to provide sufficient information to predict the dynamics of a rumor. Moreover, we get similar simulation results in the case of nonlinear transmission rate. (C) 2021 Published by Elsevier B.V.
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
Zhou, Bin-qianApata, Charles OmotomideZhou, Yi-fanJiang, Long...
14页查看更多>>摘要：Noise and noise propagation are vital in various biological processes. In a phenotypic transition cascade of colonic cells, there are three compartments: stem cells (SCs), transit-amplifying cells (TACs), and fully differentiated cells (FDCs). Instead of pure linear feedback (L) or pure saturation feedback (S) in regulating SCs and TACs differentiation, four coupled feedbacks including LL, LS, SL, and SS are considered to compare the impacts of different feedbacks on noise and noise propagation of cells. Rather than LL feedback and LS feedback, SL feedback and SS feedback have obvious advantages: Firstly, the characteristics of cells steady states changing with the parameter are more consistent with the tumor development. Secondly, as long as the key parameter is adjusted reasonably, the strong correlation between any two fluctuations of cells can be effectively utilized or avoided. Finally, although there is no direct interaction between SCs and FDCs, the noise in SCs can propagate to FDCs by TACs. And the transmitted noise from upstream cells can cause the large total noise of downstream cells even the number of downstream cells is large. The strong correlation and noise propagation between upstream and downstream cells may be the theoretical basis of the targeted therapy, which can achieve dual or even triple-drug targeted anti-tumor therapy by acting on different targets in the upstream or downstream pathways. Therefore, SL feedback or SS feedback may be a better choice for SCs and TACs to adjust their differentiation rather than LL feedback and LS feedback. This work is an extension and application of the elementary fluctuation theory of statistical physics in life system. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:- NSTL
- Elsevier
Dlask, MartinKukal, Jaromir
11页查看更多>>摘要：The work presents a methodology to precise simulation and parameter estimation of multidimensional fractional Brownian motion (fBm). The simulation approach uses circulant embedding algorithm and solution of Poisson equation, while generalizing it to multiple dimensions. For estimation, a method using Wishart distribution and maximum likelihood is presented and verified on simulated data. Unlike approximate methods for generating multidimensional fBm and its Hurst exponent estimation, this approach shows unbiased results for all processes with short memory and majority of cases with long memory. The methodology is applied to mammography screening images to find significant differences between benign and cancerous breast lumps. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:- NSTL
- Elsevier
Payne, ScottFuller, EdgarSpirou, GeorgeZhang, Cun-Quan...
22页查看更多>>摘要：The Automatic Quasi-Clique Merger algorithm is a new algorithm adapted from early work published under the name QCM (introduced by Ou and Zhang (2007)). The AQCM algorithm performs hierarchical clustering in any data set for which there is an associated similarity measure quantifying the similarity of any data i and data j. Importantly, the method exhibits two valuable performance properties: (1) the ability to automatically return either a larger or smaller number of clusters depending on the inherent properties of the data rather than on a parameter. (2) the ability to return a very large number of relatively small clusters automatically when such clusters are reasonably well defined in a data set. In this work we present the general idea of a quasiclique agglomerative approach, provide the full details of the mathematical steps of the AQCM algorithm, and explain some of the motivation behind the new methodology. The main achievement of the new methodology is that the agglomerative process now unfolds adaptively according to the inherent structure unique to a given data set, and this happens without the time-costly parameter adjustment that drove the previous QCM algorithm. For this reason we call the new algorithm automatic. We provide a demonstration of the algorithm's performance at the task of community detection in a social media network of 22,900 nodes. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:- NSTL
- Elsevier
Shi, YihanXu, JieZhang, HuiJia, Limin...
18页查看更多>>摘要：As bottlenecks of walking facilities in subway stations, merging passages are prone to congestion when passengers walk and evacuate under daily operation and emergency conditions. The general social force model (SFM) can accurately reproduce the self-organization phenomena of passenger crowds, such as the strip and lane formation. However, the SFM cannot model the overtaking behaviors of individuals who try to avoid collisions with the preceding walkers. To depict the walking behaviors of passengers in merging passages, the SFM is improved by considering the overtaking behaviors of passengers (OSFM) in this paper. Firstly, the trajectories of heterogeneous passengers are abstracted from video footages including the processes of overtaking behaviors. Next, the principle of overtaking, which leads passenger to detour with the shortest route and avoid colliding with the preceding passenger, is put forward to reproduce the overtaking processes of heterogeneous passengers in merging passages. The OSFM is verified to be more accurate than the social force model with only a centripetal force appended (ISFM). Then, the probability of overtaking behavior is estimated based on analysis of the simulation scenarios with various population densities. Finally, some simulation experiments of heterogeneous passengers with different arrival intervals in the merging passages are conducted based on the OSFM. The results show that when population density is below 0.08 ped/m(2) or exceeds 1.56 ped/m(2), the overtaking behavior scarcely occurs, but when the density is in the range of 0.25-0.4 ped/m(2), the overtaking behaviors are mostly likely to occur. The probability of overtaking behavior will decrease with the density increasing when the density exceeds 0.4 ped/m(2). What is more, the total passing time and walking speeds are more sensitive to the change of layouts of merging passages when the arrival interval of passengers obeys exponential distribution. (C) 2021 Published by Elsevier B.V.
原文链接:- NSTL
- Elsevier
Levashov, V. A.Ryltsev, R. E.Chtchelkatchev, N. M.
13页查看更多>>摘要：We investigate the degree of local structural similarity between the parent-liquid and children-crystal states for a model soft-matter system of particles interacting through the harmonic-repulsive pair potential. At different pressures, this simple system crystallizes into several significantly different crystal structures. Therefore, the model is well suited for addressing the question under consideration. In our studies, we carefully analyze the developments of the pair and triple correlation functions for the parent-liquid as the pressure increases. In particular, these considerations allow us to address the similarities in the orientational orderings of the corresponding liquid and solid phases. It is demonstrated that the similarities in the orientational ordering between the two states extend beyond the first and second neighbors. Currently, it is widely accepted that orientational ordering is important for understanding the behaviors of liquids, supercooled liquids, and the development of detailed theories of the crystallization process. Our results suggest that, up to a certain degree, it might be possible to predict the structures of the children-solids from studies of the parent-liquids. Our results raise anew a general question of how much insight into the properties of the liquid-state can be gained from drawing a parallel with the solid-state. (C) 2021 Elsevier B.V. All rights reserved.
原文链接:- NSTL
- Elsevier
Ji, ZhaoxuFan, PeiruZhang, Huanguo
24页查看更多>>摘要：We introduce a class of two-level multi-particle Greenberger-Horne-Zeilinger (GHZ) states, and study entanglement swapping between two systems for Bell states and the class of GHZ states in qubit systems, respectively. We give the formulas for the entanglement swapping of Bell states and GHZ states in any number of qubit systems. We further consider entanglement swapping between any number of Bell states and between any number of the introduced GHZ states, and propose a series of entanglement swapping schemes in a detailed way. We illustrate the applications of such schemes in quantum information processing by proposing quantum protocols for quantum key distribution, quantum secret sharing and quantum private comparison. (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
