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Predictive simulations of complex systems are essential for applications ranging from weather forecasting to drug design. The veracity of these predictions hinges on their capacity to capture the effective system dynamics. Massively…

Computational Physics · Physics 2021-10-20 Pantelis R. Vlachas , Georgios Arampatzis , Caroline Uhler , Petros Koumoutsakos

Multi-task learning (MTL) seeks to improve the generalized performance of learning specific tasks, exploiting useful information incorporated in related tasks. As a promising area, this paper studies an MTL-based control approach…

Systems and Control · Electrical Eng. & Systems 2024-08-01 Andres Arias , Chuangchuang Sun

Multi-task learning (MTL) has been widely adopted for its ability to simultaneously learn multiple tasks. While existing gradient manipulation methods often yield more balanced solutions than simple scalarization-based approaches, they…

Machine Learning · Computer Science 2025-09-29 Peiyao Xiao , Chaosheng Dong , Shaofeng Zou , Kaiyi Ji

In this work, we study controllability in the set of all density matrices for a two-level open quantum system driven by coherent and incoherent controls. In [A. Pechen, Phys. Rev. A 84, 042106 (2011)] an approximate controllability, i.e.,…

Quantum Physics · Physics 2025-02-21 Lev Lokutsievskiy , Alexander Pechen

We study the problem of learning a mixture of multiple linear dynamical systems (LDSs) from unlabeled short sample trajectories, each generated by one of the LDS models. Despite the wide applicability of mixture models for time-series data,…

Machine Learning · Statistics 2022-05-26 Yanxi Chen , H. Vincent Poor

The optical response of an electronic two-level system (TLS) coupled to an incident continuous wave (cw) electromagnetic (EM) field is simulated explicitly in one dimension by the following five approaches: (i) the coupled Maxwell-Bloch…

Optics · Physics 2019-03-19 Tao E. Li , Hsing-Ta Chen , Joseph E. Subotnik

We develop an algorithm for the motion and task planning of a system comprised of multiple robots and unactuated objects under tasks expressed as Linear Temporal Logic (LTL) constraints. The robots and objects evolve subject to uncertain…

Systems and Control · Electrical Eng. & Systems 2022-04-26 Christos K. Verginis , Yiannis Kantaros , Dimos V. Dimarogonas

Tunneling two-level systems (TLSs), generic to amorphous solids, dictate the low-temperature properties of amorphous solids and dominate noise and decoherence in quantum nano-devices. The properties of the TLSs are generally described by…

Disordered Systems and Neural Networks · Physics 2021-02-25 Alexander Churkin , Shlomi Matityahu , Andrii O. Maksymov , Alexander L. Burin , Moshe Schechter

This paper develops a novel machine learning-based framework using Semi-Supervised Multi-Task Learning (SS-MTL) for power system dynamic security assessment that is accurate, reliable, and aware of topological changes. The learning…

Machine Learning · Computer Science 2024-07-15 Muhy Eddin Za'ter , Amirhossein Sajadi , Bri-Mathias Hodge

This work introduces a general multi-level model for self-adaptive systems. A self-adaptive system is seen as composed by two levels: the lower level describing the actual behaviour of the system and the upper level accounting for the…

Logic in Computer Science · Computer Science 2013-05-16 Emanuela Merelli , Nicola Paoletti , Luca Tesei

Sensitivity analysis methods are important tools for research and design with simulations. Many important simulations exhibit chaotic dynamics, including scale-resolving turbulent fluid flow simulations. Unfortunately, conventional…

Chaotic Dynamics · Physics 2018-01-17 Patrick J. Blonigan , Qiqi Wang

We have demonstrated that near complete coherence can be achieved in a four level double lambda-like systems using a train of ultra-short optical pulses. The effect of the Doppler broadening has been analyzed and a scheme has been proposed…

Optics · Physics 2014-01-16 Pawan Kumar , Amarendra K. Sarma

The ground state electron density -- obtainable using Kohn-Sham Density Functional Theory (KS-DFT) simulations -- contains a wealth of material information, making its prediction via machine learning (ML) models attractive. However, the…

It is frequently observed that even at very low temperatures the number of quasiparticles in superconducting materials is higher than predicted by standard BCS-theory. These quasiparticles can interact with two-level systems, such as…

Mesoscale and Nanoscale Physics · Physics 2016-01-18 Sebastian Zanker , Michael Marthaler , Gerd Schön

We measure the coherent scattering of light by a cloud of laser-cooled atoms with a size comparable to the wavelength of light. By interfering a laser beam tuned near an atomic resonance with the field scattered by the atoms we observe a…

In this work, we present a multiple-scale perturbation technique suitable for the study of open quantum systems, which is easy to implement and in few iterative steps allows us to find excellent approximate solutions. For any time-local…

Quantum Physics · Physics 2019-04-30 D. N. Bernal-García , B. A. Rodríguez , H. Vinck-Posada

Upon the significant performance of the supervised deep neural networks, conventional procedures of developing ML system are \textit{task-centric}, which aims to maximize the task accuracy. However, we scrutinized this \textit{task-centric}…

Computer Vision and Pattern Recognition · Computer Science 2022-10-14 Kyung Ho Park , Hyunhee Chung , Soonwoo Kwon

Recent advancements in technology have established terrestrial laser scanners (TLS) as a powerful instrument in geodetic deformation analysis. As TLS becomes increasingly integrated into this field, it is essential to develop a…

Applications · Statistics 2025-10-30 Omar AbdelGafar , Selin Palaz , Yihui Yang , Christoph Holst

The low temperature physics of structurally amorphous materials is governed by two-level system defects (TLS), the exact origin and nature of which remain elusive despite decades of study. Recent advances towards realising stable…

Multidimensional coherent spectroscopy (MDCS) has been established in quantum chemistry as a powerful tool for studying the nonlinear response and nonequilibrium dynamics of molecular systems. More recently, the technique has also been…

Strongly Correlated Electrons · Physics 2025-05-12 Jiyu Chen , Philipp Werner