Physical review. E最新文献

Performance at maximum figure of merit for a Brownian Carnot refrigerator 布朗卡诺制冷器的最大功勋值性能

IF 2.4 3区物理与天体物理

Physical review. E Pub Date : 2024-08-12 DOI: 10.1103/physreve.110.024123

O. Contreras-Vergara, G. Valencia-Ortega, N. Sánchez-Salas, J. I. Jiménez-Aquino

{"title":"Performance at maximum figure of merit for a Brownian Carnot refrigerator","authors":"O. Contreras-Vergara, G. Valencia-Ortega, N. Sánchez-Salas, J. I. Jiménez-Aquino","doi":"10.1103/physreve.110.024123","DOIUrl":"https://doi.org/10.1103/physreve.110.024123","url":null,"abstract":"This paper focuses on the coefficient of performance (COP) at maximum <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msup><mi>χ</mi><mi>R</mi></msup></math> figure of merit for a Brownian Carnot-like refrigerator, within the context of the low-dissipation approach. Our proposal is based on the Langevin equation for a Brownian particle bounded to a harmonic potential trap, which can perform Carnot-like cycles at finite time. The theoretical approach is related to the equilibrium ensemble average of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mrow><mo>〈</mo><msup><mi>x</mi><mn>2</mn></msup><mo>〉</mo></mrow><mi>eq</mi></msub></math> which plays the role of a statelike equation, <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>x</mi></math> being the Brownian particle position. This statelike equation comes from the macroscopic version of the corresponding Langevin equation for a Brownian particle. We show that under quasistatic conditions the COP has the same expression as the macroscopic Carnot refrigerator, while for irreversible cycles at finite time and under symmetric dissipation the optimal COP is the counterpart of Curzon-Ahlborn efficiency as also obtained for irreversible macroscopic refrigerators.","PeriodicalId":20085,"journal":{"name":"Physical review. E","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141938847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Testing for Markovian character of transfer of fluctuations in solar wind turbulence on kinetic scales 测试太阳风湍流波动在动力学尺度上的马尔可夫转移特性

IF 2.4 3区物理与天体物理

Physical review. E Pub Date : 2024-08-12 DOI: 10.1103/physreve.110.025203

Dariusz Wójcik, Wiesław M. Macek

{"title":"Testing for Markovian character of transfer of fluctuations in solar wind turbulence on kinetic scales","authors":"Dariusz Wójcik, Wiesław M. Macek","doi":"10.1103/physreve.110.025203","DOIUrl":"https://doi.org/10.1103/physreve.110.025203","url":null,"abstract":"We apply statistical analysis to search for processes responsible for turbulence in physical systems. In our previous studies, we have shown that solar wind turbulence in the inertial range of large magnetohydrodynamic scales exhibits Markov properties. We have recently extended this approach on much smaller kinetic scales. Here we are testing for the Markovian character of stochastic processes in a kinetic regime based on magnetic field and velocity fluctuations in the solar wind, measured onboard the Magnetospheric Multiscale (MMS) mission: behind the bow shock, inside the magnetosheath, and near the magnetopause. We have verified that the Chapman-Kolmogorov necessary conditions for Markov processes is satisfied for local transfer of energy between the magnetic and velocity fields also on kinetic scales. We have confirmed that for magnetic fluctuations, the first Kramers-Moyal coefficient is linear, while the second term is quadratic, corresponding to drift and diffusion processes in the resulting Fokker-Planck equation. It means that magnetic self-similar turbulence is described by generalized Ornstein-Uhlenbeck processes. We show that for the magnetic case, the Fokker-Planck equation leads to the probability density functions of the kappa distributions, which exhibit global universal scale invariance with a linear scaling and lack of intermittency. On the contrary, for velocity fluctuations, higher order Kramers-Moyal coefficients should be taken into account and hence scale invariance is not observed. However, the nonextensity parameter in Tsallis entropy provides a robust measure of the departure of the system from equilibrium. The obtained results are important for a better understanding of the physical mechanism governing turbulent systems in space and laboratory.","PeriodicalId":20085,"journal":{"name":"Physical review. E","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141938791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dispersion network-transition entropy: A metric for characterizing the complexity of nonlinear signals 分散网络-转换熵：表征非线性信号复杂性的指标

IF 2.4 3区物理与天体物理

Physical review. E Pub Date : 2024-08-12 DOI: 10.1103/physreve.110.024205

Bo Geng, Haiyan Wang, Xiaohong Shen, Hongwei Zhang, Yongsheng Yan

{"title":"Dispersion network-transition entropy: A metric for characterizing the complexity of nonlinear signals","authors":"Bo Geng, Haiyan Wang, Xiaohong Shen, Hongwei Zhang, Yongsheng Yan","doi":"10.1103/physreve.110.024205","DOIUrl":"https://doi.org/10.1103/physreve.110.024205","url":null,"abstract":"Extracting meaningful information from signals has always been a challenge. Due to the influence of environmental noise, collected signals often exhibit nonlinear characteristics, rendering traditional metrics inadequate in capturing the dynamic properties and complex structures of signals. To address this challenge, this study proposes an innovative metric for quantifying signal complexity—dispersion network-transition entropy (DNTE), which integrates the concepts of complex networks and information entropy. Specifically, we assign single cumulative distribution function values to network nodes and utilize Markov chains to represent links, transforming nonlinear signals into weighted directed complex networks. Subsequently, we assess the importance of network nodes and links, and employ the mathematical expression of information entropy to calculate the DNTE value, quantifying the complexity of the original signal. Next, through extensive experiments on simulated chaotic models and real underwater acoustic signals, we confirm the outstanding performance of DNTE. The results indicate that, compared to Lempel-Ziv complexity, permutation entropy, and dispersion entropy, DNTE not only more accurately reflects changes in signal complexity but also exhibits higher computational efficiency. Importantly, DNTE demonstrates optimal performance in distinguishing different categories of chaotic models, ships, and modulation signals, showcasing its significant potential in extracting effective information from signals.","PeriodicalId":20085,"journal":{"name":"Physical review. E","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141938787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Interaction between gas channels in water-saturated sands 水饱和砂中气体通道之间的相互作用

IF 2.4 3区物理与天体物理

Physical review. E Pub Date : 2024-08-12 DOI: 10.1103/physreve.110.024901

Germán Varas, Gabriel Ramos, Valérie Vidal

{"title":"Interaction between gas channels in water-saturated sands","authors":"Germán Varas, Gabriel Ramos, Valérie Vidal","doi":"10.1103/physreve.110.024901","DOIUrl":"https://doi.org/10.1103/physreve.110.024901","url":null,"abstract":"This work investigates the interaction between gas channels in a vertical Hele-Shaw cell when air is injected simultaneously from two points at a constant flow rate. Unlike single-injection experiments, this dual-point system induces the formation of numerous bubbles, thereby intensifying the interactions between air channels. We use an image analysis technique for tracking motion in the granular bed to define a flow density parameter throughout the cell. The vertical accumulation of this parameter (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>n</mi><mi>z</mi></msub></math>) reveals two specific heights, one marking a finger-to-fracture transition and another indicating the average interaction height of the air channels. Conversely, its horizontal accumulation (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>n</mi><mi>x</mi></msub></math>) assesses the extent of overlap in the fluidized zones created by each airflow. Notably, the analysis indicates that the optimum distribution of the three phases in the system is more closely related to the interaction's variability than its intensity. This finding is significant for industrial applications such as air sparging and catalytic reactors.","PeriodicalId":20085,"journal":{"name":"Physical review. E","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141938790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Variational time reversal for free-energy estimation in nonequilibrium steady states 非平衡稳态自由能估算的变分时间反演

IF 2.4 3区物理与天体物理

Physical review. E Pub Date : 2024-08-12 DOI: 10.1103/physreve.110.024120

Jorge L. Rosa-Raíces, David T. Limmer

引用次数: 0

Dynamic flexoelectric instabilities in nematic liquid crystals 向列液晶中的动态柔电不稳定性

IF 2.4 3区物理与天体物理

Physical review. E Pub Date : 2024-08-12 DOI: 10.1103/physreve.110.024701

E. S. Pikina, A. R. Muratov, E. I. Kats, V. V. Lebedev

{"title":"Dynamic flexoelectric instabilities in nematic liquid crystals","authors":"E. S. Pikina, A. R. Muratov, E. I. Kats, V. V. Lebedev","doi":"10.1103/physreve.110.024701","DOIUrl":"https://doi.org/10.1103/physreve.110.024701","url":null,"abstract":"Electrohydrodynamic phenomena in liquid crystals constitute an old but still very active research area. The reason is that these phenomena play the key role in various applications of liquid crystals and due to the general interest of the physical community in out-of-equilibrium systems. Nematic liquid crystals (NLCs) are ideally representative for such investigations. Our article aims to study theoretically the linear NLCs dynamics. We include into consideration orientation elastic energy, hydrodynamic motion, external alternating electric field, electric conductivity, and flexoelectric polarization. We analyze the linear stability of the NLC film, determining dynamics of perturbations with respect to the homogeneous initial state of the NLC. For the purpose we compute eigenvalues of the evolution matrix for a period of the external alternating electric field. These eigenvalues determine the amplification factors for the modes during the period. The instability occurs when the principal eigenvalue of the evolution matrix becomes unity by its absolute value. The condition determines the threshold (critical field) for the instability of the uniform state. It turns out that one might expect various types of the instability, only partially known and investigated in the literature. Particularly, we find that the flexoelectric instability may lead to two-dimensionally space-modulated patterns exhibiting time oscillations. This type of the structures was somehow overlooked in the previous works. We formulate conditions needed for the scenario to be realized. We hope that the results of our work will open the door to a broad range of further studies. Of especial importance would be a comprehensive understanding of the role of various material parameters and nonlinear effects which is a key step for the rational design of NLCs exhibiting the predicted in this publication multidimensional oscillating in time patterns.","PeriodicalId":20085,"journal":{"name":"Physical review. E","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141969156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fast decisions reflect biases; slow decisions do not 快速决策反映偏见，缓慢决策不反映偏见

IF 2.4 3区物理与天体物理

Physical review. E Pub Date : 2024-08-12 DOI: 10.1103/physreve.110.024305

Samantha Linn, Sean D. Lawley, Bhargav R. Karamched, Zachary P. Kilpatrick, Krešimir Josić

引用次数: 0

Self-organization of anti-aligning active particles: Waving pattern formation and chaos 反排列活性粒子的自组织：挥舞图案的形成与混沌

IF 2.4 3区物理与天体物理

Physical review. E Pub Date : 2024-08-12 DOI: 10.1103/physreve.110.024603

Daniel Escaff

引用次数: 0

Heat capacity of periodically driven two-level systems 周期性驱动两级系统的热容量

IF 2.4 3区物理与天体物理

Physical review. E Pub Date : 2024-08-12 DOI: 10.1103/physreve.110.024121

Elena Rufeil Fiori, Christian Maes

引用次数: 0

Self-limiting stacks of curvature-frustrated colloidal plates: Roles of intraparticle versus interparticle deformations 曲率受挫胶体板的自限制堆叠：粒子内变形与粒子间变形的作用

IF 2.4 3区物理与天体物理

Physical review. E Pub Date : 2024-08-09 DOI: 10.1103/physreve.110.024602

Kyle T. Sullivan, Ryan C. Hayward, Gregory M. Grason

{"title":"Self-limiting stacks of curvature-frustrated colloidal plates: Roles of intraparticle versus interparticle deformations","authors":"Kyle T. Sullivan, Ryan C. Hayward, Gregory M. Grason","doi":"10.1103/physreve.110.024602","DOIUrl":"https://doi.org/10.1103/physreve.110.024602","url":null,"abstract":"In geometrically frustrated assemblies local intersubunit misfits propagate to intra-assembly strain gradients, giving rise to anomalous self-limiting assembly thermodynamics. Here we use theory and coarse-grained simulation to study a recently developed class of “curvamer” particles, flexible shell-like particles that exhibit self-limiting assembly due to the build up of curvature deformation in cohesive stacks. To address a generic, yet poorly understood aspect of frustrated assembly, we introduce a model of curvamer assembly that incorporates both intraparticle shape deformation as well as compliance of interparticle cohesive gaps, an effect we can attribute to a finite range of attraction between particles. We show that the ratio of intraparticle (bending elasticity) to interparticle stiffness not only controls the regimes of self-limitation but also the nature of frustration propagation through curvamer stacks. We find a transition from uniformly bound, curvature-focusing stacks at small size to gap opened, uniformly curved stacks at large size is controlled by a dimensionless measure of inter- versus intracurvamer stiffness. The finite range of interparticle attraction determines the range of cohesion in stacks that are self-limiting, a prediction which is in strong agreement with numerical studies of our coarse-grained colloidal model. These predictions provide critical guidance for experimental realizations of frustrated particle systems designed to exhibit self-limitation at especially large multiparticle scales.","PeriodicalId":20085,"journal":{"name":"Physical review. E","volume":null,"pages":null},"PeriodicalIF":2.4,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141938792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0