Article
Physics, Multidisciplinary
A. McDonald, A. A. Clerk
Summary: In this paper, we demonstrate how the presence of continuous weak symmetry can be used to analytically diagonalize the Liouvillian of a class of Markovian dissipative systems with strong interactions or nonlinearity. This method enables an exact description of the full dynamics and dissipative spectrum, providing a powerful new tool for the study of complex driven-dissipative quantum systems.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Ovidiu Patu, Dmitri Averin
Summary: This study investigates the persistent currents in the fermionic one-dimensional Hubbard model under strong-interacting conditions. The researchers find that the current can change its flux period and sign as a function of temperature, in addition to an unexpected increase in magnitude with temperature. The decay rate also varies depending on the polarization of the system.
PHYSICAL REVIEW LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Maxim Dzero, Alex Levchenko
Summary: We study a two-dimensional electron system with short-ranged nonmagnetic disorder potential, Coulomb interactions, and Rashba spin-orbit coupling. By employing the path-integral approach within the Keldysh formalism, we derive the kinetic equation for the semiclassical Green's function and use it to calculate the spin current within the linear response theory. The frequency dependence of the spin Hall conductivity is examined, and the role of electron interactions at finite temperatures in both ballistic and diffusive transport regimes is explained.
Article
Mathematics
Changchun Liu, Ming Mei, Jiaqi Yang
Summary: This paper focuses on a class of nonlocal reaction-diffusion equations with time-delay and degenerate diffusion. It is shown that the Cauchy problem of the equation possesses a Holder-continuous solution affected by the degeneracy of diffusion. Additionally, non-critical traveling waves are proven to be globally L-1-stable, with a derived time-exponential convergence rate. The approach used for the proof combines technical L-1-weighted energy estimates with compactness analysis, incorporating new developments.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2022)
Article
Mathematics, Applied
Quanjun Lang, Fei Lu
Summary: In this paper, we propose a nonparametric algorithm to learn the interaction kernels of mean-field equations for first-order systems of interacting particles. The algorithm efficiently learns the kernel in data-adaptive hypothesis spaces using least squares with regularization. A key aspect of the algorithm is a probabilistic error functional derived from the likelihood ratio of the mean-field equation's diffusion process. The estimator converges in a weighted L2 space at a rate determined by the trade-off between the numerical error and approximation error.
SIAM JOURNAL ON SCIENTIFIC COMPUTING
(2022)
Article
Mathematics, Applied
Bingtao Han, Daqing Jiang
Summary: In this paper, two stochastic vegetation-water dynamic systems are proposed and studied. The first system focuses on the deterministic case and analyzes the equilibria and stability. The second system perturbed by Gaussian white noise is investigated to establish conditions for the existence and uniqueness of ergodic stationary distribution. The paper also explores the extinction criteria and stationary distribution in the presence of both white and colored noise.
COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION
(2023)
Article
Mathematics, Applied
Min Zhu, Dezhi Liu
Summary: This work focuses on the convergence rate of the Euler-Maruyama scheme for distribution-independent and distribution-dependent stochastic differential equations with unbounded and Dini continuous drifts. The study introduces a new Zvonkintype transformation to investigate the convergence rate of the Euler-Maruyama scheme for stochastic differential equations with singular coefficients and unbounded drifts. In addition, the approximation issue of a class of distribution-dependent stochastic differential equations with singular drifts is analyzed using interacting particle systems.
COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION
(2023)
Article
Materials Science, Multidisciplinary
Tianci Zhou, Andrew Guo, Shenglong Xu, Xiao Chen, Brian Swingle
Summary: The FKPP equation provides a mean-field theory for out-of-time ordered commutators in quantum chaotic systems. The fractional-derivative FKPP equation offers a mean-field theory for systems with power-law interactions. However, the fractional FKPP description is subject to strong quantum fluctuation effects, and its effectiveness for generic chaotic systems with power-law interactions is unclear. This study investigates this problem using a model of coupled quantum dots and demonstrates that the parameters of the effective theory can be chosen to reproduce the previously found butterfly light cone scalings.
Article
Environmental Sciences
S. S. Prijith, M. V. R. Sesha Sai
Summary: This study quantifies trends in free-tropospheric aerosol loading over the Indian landmass using multi-satellite observations and reanalysis data. It finds increasing trends in free-tropospheric aerosol abundance over most regions and seasons, with the strongest positive trend seen in post-monsoon. Dust aerosol loading decreases while smoke aerosol concentration increases. Northwest India plays a significant role in aerosol production, with aerosols transported through the Indo Gangetic Plain and causing enhancement in free-tropospheric aerosol loading over central India and southern peninsula in post-monsoon. These findings are important for understanding the impact of free-tropospheric aerosols on the atmosphere.
ATMOSPHERIC ENVIRONMENT
(2022)
Article
Materials Science, Multidisciplinary
Laila A. Al-essa, Wafa F. Alfwzan, F. M. Aldosari, A. -B. A. Mohamed, H. Eleuch
Summary: The dynamics of the Wigner distribution function (WDF) of time-dependent resonator coherent field states produced by a flux qubit's interaction with a resonator-field is analyzed in this study. The non-classicality of the WDF, associated with the mixedness resonator entropy dynamics, can be controlled by varying the qubit-resonator interaction, detuning, and decoherence. The intrinsic decoherence significantly affects the non-classicality of the WDF, as indicated by the negative values of the WDF.
RESULTS IN PHYSICS
(2023)
Article
Physics, Multidisciplinary
Vasily E. Tarasov
Summary: This paper generalizes a simple model of quantum mechanics and statistics to incorporate power-law nonlocality, utilizing fractional differential equations and fractal distribution of states. It addresses the complex properties of systems such as power-law spatial nonlocality, long-range interactions, and fractal distribution of permitted states. The proposed quantum statistical model successfully accounts for power-law nonlocality, long-range interactions, and fractal distribution of quantum states.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2021)
Article
Physics, Mathematical
Paul Dupuis, Georgi S. Medvedev
Summary: In this article, we utilize the weak convergence approach to study the large deviation principle in W-random graphs and extend it to interacting dynamical systems. We demonstrate the continuous dependency of solutions on the underlying graphs in the cut-norm topology and apply the contraction principle for the translation.
COMMUNICATIONS IN MATHEMATICAL PHYSICS
(2022)
Article
Engineering, Environmental
Gopinathan R. Abhijith, Avi Ostfeld
Summary: The complexity of modeling water quality variations in water distribution systems is discussed in this article. The existing macroscale models have limitations in representing reaction mechanisms and intermediate formation. To overcome these limitations, a new approach based on metabolic network modeling principles is proposed.
Article
Automation & Control Systems
Hao Ma, Henk A. P. Blom
Summary: This paper investigates the application of the interacting particle system (IPS) approach in probability estimation for general stochastic hybrid systems (GSHS). The paper analyzes two basic simulation methods for GSHS execution and identifies an unobservable state component introduced by the transformation from spontaneous jumps to forced jumps. To address this issue, the paper proposes an enriched GSHS transformation and demonstrates the improved IPS reach probability estimation through simulation results for a simple GSHS example.
NONLINEAR ANALYSIS-HYBRID SYSTEMS
(2023)
Article
Engineering, Multidisciplinary
Pascal Weinmueller, Thomas Takacs
Summary: This paper develops and studies the construction of approximately smooth bases for isogeometric analysis over two-patch domains, focusing on achieving C-1 conditions in isogeometric spaces and optimizing convergence under h-refinement by introducing local functions of higher polynomial degree and lower regularity.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Automation & Control Systems
Mauro Franceschelli, Paolo Frasca
Summary: This article discusses open multiagent systems (OMASs), where an indefinite number of agents may join or leave the network at any time. A novel theoretical framework is proposed to study the dynamical properties of OMASs, focusing on stability and deriving sufficient conditions for it. The analysis considers the arrival/departure of agents as a disturbance and requires bounded effects of arrivals/departures for stability, also requiring OMASs to be contractive in the absence of arrivals/departures.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2021)
Article
Engineering, Civil
Vittorio Giammarino, Simone Baldi, Paolo Frasca, Maria Laura Delle Monache
Summary: Field experiments on ring roadways with human-driven vehicles or a mix of human-driven and autonomous vehicles have been conducted, leading to the proposal of a new interconnected stability notion named weak ring stability. This new stability concept, combined with classical stability, aims to explain phenomena observed in field experiments and highlight possibilities and limitations of traffic control via sparse autonomous vehicles. By designing AV controllers with improved string stability specifications, it may be possible to control traffic flow effectively, albeit with a reduction in the number of autonomous vehicles operating.
IEEE TRANSACTIONS ON INTELLIGENT TRANSPORTATION SYSTEMS
(2021)
Article
Physics, Mathematical
Giacomo Dimarco, Andrea Tosin, Mattia Zanella
Summary: In this paper, second order hydrodynamic traffic models are derived from kinetic-controlled equations for driver-assist vehicles, taking into account two main control strategies. The presence of driver-assist vehicles leads to an aggregate homogenisation of mean flow speed, optimizing flow and traffic stabilisation.
JOURNAL OF STATISTICAL PHYSICS
(2022)
Article
Automation & Control Systems
Denis Nikitin, Carlos Canudas-de-Wit, Paolo Frasca
Summary: This article discusses the problem of controlling the average state of a large-scale linear network to a constant reference value, and proposes a design for an output-feedback controller that does not require information about the state vector or system matrices. By satisfying a sign condition on the system matrices, this controller can have arbitrary positive gains. To ensure that the network states are close to the average state, a novel extremum seeking algorithm is used to solve the deviation minimization problem.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2022)
Article
Multidisciplinary Sciences
Nadia Loy, Matteo Raviola, Andrea Tosin
Summary: In this paper, a Boltzmann-type kinetic description for opinion formation on social networks is proposed, taking into account a general connectivity distribution of the individuals. The structure of the social network is described statistically, and it is found that a non-zero correlation between the initial opinions and the connectivity of the individuals is necessary to observe a polarization switch.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2022)
Article
Engineering, Civil
Francesco Acciani, Paolo Frasca, Geert Heijenk, Anton A. Stoorvogel
Summary: This paper discusses achieving stable vehicle platooning using Cooperative Adaptive Cruise Control in the presence of unreliable communication and message losses. By modeling communication losses as independent random events and proposing a novel design for the cooperative controller, the effects of the losses are effectively mitigated. The control design explicitly considers the stochastic nature of the losses, leading to both plant stability and string stability of the average error dynamics while minimizing the variance of trajectories around their average. Simulation results demonstrate that the proposed controller can compensate for losses even under high loss probabilities.
IEEE TRANSACTIONS ON INTELLIGENT TRANSPORTATION SYSTEMS
(2022)
Article
Automation & Control Systems
Denis Nikitin, Carlos Canudas-de-Wit, Paolo Frasca
Summary: In this article, a continuation method is presented to transform spatially distributed ODE systems into continuous PDE. The method is applicable to both linear and nonlinear systems, including multidimensional, space-varying, and time-varying systems. The method is illustrated with multiple examples and successfully applied to the continuousization of a Newtonian system and the control problem of multiagent systems.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2022)
Article
Automation & Control Systems
Wilbert Samuel Rossi, Jan Willem Polderman, Paolo Frasca
Summary: This article analyzes a model of user interaction with an online news aggregator, highlighting the feedback loop between user opinions, personalized recommendations, and opinion evolution. The study shows that personalized recommendations have a significant impact on opinion evolution and tend to result in more extreme opinions.
IEEE TRANSACTIONS ON CONTROL OF NETWORK SYSTEMS
(2022)
Article
Automation & Control Systems
Massimo Bini, Paolo Frasca, Chiara Ravazzi, Fabrizio Dabbene
Summary: This article discusses a dynamic model for competition in a social network, presenting more refined heuristics for optimal targeting problems. By leveraging analytical solutions and electrical analogies, the proposed approach offers more effective solutions compared to traditional greedy methods, particularly for tree-like and sparse graphs. This new algorithm accelerates the selection of optimal solutions on trees and performs well in both randomly generated and real social networks when compared to zero-cost heuristics.
IEEE TRANSACTIONS ON CONTROL OF NETWORK SYSTEMS
(2022)
Article
Engineering, Civil
Cristina Magnetti Gisolo, Maria Laura Delle Monache, Francesco Ferrante, Paolo Frasca
Summary: In this study, the collective vehicle dynamics of a group of homogeneous vehicles traveling on a ring road are investigated using the Optimal Velocity Model. The stability and safety aspects of the equilibrium motion regime are analyzed through linearization and solving suitable Linear Matrix Inequalities.
IEEE TRANSACTIONS ON INTELLIGENT TRANSPORTATION SYSTEMS
(2022)
Article
Automation & Control Systems
Tommaso Toso, Alain Y. Kibangou, Paolo Frasca
Summary: Nowadays, many car drivers use navigation apps to decide which route to take. These apps increasingly rely on real-time data instead of historical data for efficiency. However, due to the necessary steps of data collection, communication, and processing, delay is inevitable. To address this, a macroscopic dynamic traffic assignment model is introduced to describe driver behavior in choosing routes. The model assumes that some drivers follow a navigation app's directions, which are based on delayed traffic data. Through stability analysis, the excessive delay in traffic data is shown and quantified, revealing its negative impact on network efficiency through oscillating trajectories and unsatisfied demand.
IEEE CONTROL SYSTEMS LETTERS
(2023)
Article
Mathematics, Applied
Felisia Angela Chiarello, Andrea Tosin
Summary: This study examines the derivation of macroscopic traffic models from optimal speed and follow-the-leader particle dynamics, and investigates the correspondence between particle models and their macroscopic limits through numerical simulations.
KINETIC AND RELATED MODELS
(2022)
Article
Mathematics, Interdisciplinary Applications
Rossella Della Marca, Nadia Loy, Andrea Tosin
Summary: This study investigates the impact of viral load on the transmission and progression of epidemics from a theoretical perspective. A stochastic particle model is proposed to describe infection transmission and individual physiological processes of the disease. Evolution equations for the distribution of viral load in each compartment are derived, and macroscopic equations for densities and viral load momentum are obtained through upscaling procedures. The results can be used for quantitative analysis of the macroscopic dynamics of epidemics.
NETWORKS AND HETEROGENEOUS MEDIA
(2022)
Article
Mathematics, Applied
Nadia Loy, Andrea Tosin
Summary: This paper proposes a Boltzmann-type kinetic description of mass-varying interacting multi-agent systems, deriving general kinetic equations and analyzing a model for infectious disease contagion.
KINETIC AND RELATED MODELS
(2021)
Article
Computer Science, Artificial Intelligence
Di Liu, Simone Baldi, Vishrut Jain, Wenwu Yu, Paolo Frasca
Summary: This paper proposes an adaptive protocol for synchronized merging in a cyclic communication scenario, which can handle uncertain driveline time constants to ensure well-posedness of control inputs. The protocol utilizes a set of adaptive control strategies and is experimentally validated in a benchmark merging scenario.
IEEE TRANSACTIONS ON INTELLIGENT VEHICLES
(2021)
