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Hamiltonian Learning using Machine Learning Models Trained with Continuous Measurements

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arXiv 2024年

作者： Tucker, Kris Rege, Amit Kiran Smith, Conor Monteleoni, Claire Albash, Tameem Department of Applied Math University of Colorado Boulder United States Department of Computer Science University of Colorado Boulder United States Center for Quantum Information and Control University of New Mexico University of New Mexico AlbuquerqueNM United States Department of Electrical and Computer Engineering University of New Mexico AlbuquerqueNM United States INRIA Centre de Recherche de Paris France Center for Computing Research Sandia National Laboratories AlbuquerqueNM87185 United States

We build upon recent work on using Machine Learning models to estimate Hamiltonian parameters using continuous weak measurement of qubits as input. We consider two settings for the training of our model: (1) supervised learning where the weak measurement training record can be labeled with known Hamiltonian parameters, and (2) unsupervised learning where no labels are available. The first has the advantage of not requiring an explicit representation of the quantum state, thus potentially scaling very favorably to a larger number of qubits. The second requires the implementation of a physical model to map the Hamiltonian parameters to a measurement record, which we implement using an integrator of the physical model with a recurrent neural network to provide a model-free correction at every time step to account for small effects not captured by the physical model. We test our construction on a system of two qubits and demonstrate accurate prediction of multiple physical parameters in both the supervised and unsupervised contexts. We demonstrate that the model benefits from larger training sets establishing that it is in fact "learning," and we show robustness to errors in the assumed physical model by achieving accurate parameter estimation in the presence of unanticipated single particle relaxation. © 2024, CC BY.

关键词： Qubits

All electrical control and Temperature Dependence of the Spin and Valley Hall Effect in Monolayer WSe2 Transistors

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arXiv 2022年

作者： Li, Xintong Liu, Zhida Liu, Yihan Karki, Suyogya Li, Xiaoqin Akinwande, Deji Incorvia, Jean Anne C. Department of Electrical and Computer Engineering The University of Texas at Austin AustinTX78712 United States Department of Physics Center for Dynamics and Control of Materials The University of Texas at Austin AustinTX78712 United States

Heavy metal-based two-dimensional van der Waals materials have a large, coupled spin and valley Hall effect (SVHE) that has potential use in spintronics and valleytronics. Optical measurements of the SVHE have largely been performed below 30 K and understanding of the SVHE-induced spin/valley polarizations that can be electrically generated is limited. Here, we study the SVHE in monolayer p-type tungsten diselenide (WSe2). Kerr rotation (KR) measurements show the spatial distribution of the SVHE at different temperatures, its persistence up to 160 K, and that it can be electrically modulated via gate and drain bias. A spin/valley drift and diffusion model together with reflection spectra data is used to interpret the KR data and predict a lower-bound spin/valley lifetime of 4.1 ns below 90 K and 0.26 ns at 160 K. The excess spin and valley per unit length along the edge is calculated to be 109 μm-1 at 45 K, which corresponds to a spin/valley polarization on the edge of 6%. These results are important steps towards practical use of the SVHE. © 2022, CC BY.

关键词： Monolayers

Embedding Temporal Convolutional Networks for Energy-Efficient PPG-Based Heart Rate Monitoring

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arXiv 2022年

作者： Burrello, Alessio Pagliari, Daniele Jahier Maria Rapa, Pierangelo Semilia, Matilde Risso, Matteo Polonelli, Tommaso Poncino, Massimo Benini, Luca Benatti, Simone Department of Electrical Electronic and Information Engineering University of Bologna Emilia-Romagna Bologna40136 Italy Department of Control and Computer Engineering Politecnico di Torino Torino10129 Italy PBL Center Zurich8092 Switzerland Department of Information Technology and Electrical Engineering The ETH Zurich Zurich8092 Switzerland Department of Sciences and Methods for Engineering University of Modena e Reggio Emilia Emilia-Romagna Modena42123 Italy

Photoplethysmography (PPG) sensors allow for non-invasive and comfortable heart-rate (HR) monitoring, suitable for compact wrist-worn devices. Unfortunately, Motion Artifacts (MAs) severely impact the monitoring accuracy, causing high variability in the skin-to-sensor interface. Several data fusion techniques have been introduced to cope with this problem, based on combining PPG signals with inertial sensor data. Until know, both commercial and reasearch solutions are computationally efficient but not very robust, or strongly dependent on hand-tuned parameters, which leads to poor generalization performance. In this work, we tackle these limitations by proposing a computationally lightweight yet robust deep learning-based approach for PPG-based HR estimation. Specifically, we derive a diverse set of Temporal Convolutional Networks (TCN) for HR estimation, leveraging Neural Architecture Search (NAS). Moreover, we also introduce ActPPG, an adaptive algorithm that selects among multiple HR estimators depending on the amount of MAs, to improve energy efficiency. We validate our approaches on two benchmark datasets, achieving as low as 3.84 Beats per Minute (BPM) of Mean Absolute Error (MAE) on PPGDalia, which outperforms the previous state-of-the-art. Moreover, we deploy our models on a low-power commercial microcontroller (STM32L4), obtaining a rich set of Pareto optimal solutions in the complexity vs. accuracy space. © 2022, CC BY.

关键词： Deep learning

Three-Phase D-STATCOM with Digital Current control Strategy in abc-Reference Frame 3

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Three-Phase D-STATCOM with Digital Current Control Strategy ...

3rd International Conference on Computing, Mathematics and engineering Technologies, iCoMET 2020

作者： Busarello, Tiago Davi Curi Zeb, Kamran Sarwar, Muhammad Asim Kim, Hee Je Federal University of Santa Catarina - UFSC Depart. Control Automation and Computation Engineering Blumenau Brazil National University of Sciences and Technology School of Electrical Engineering School of Electrical Engineering and Computer Science Pusan National University Busan Korea Republic of Sukkur IBA University Department of Electrical Engineering Pakistan Pusan National University School of Electrical Engineering Busan Korea Republic of

ISBN: (纸本)9781728149707

This paper proposes a Three-phase D-STATCOM with digital current control strategy in abc- reference frame. The proposal D-STATCOM does not use a PLL and the reactive power is transferred to the grid through controlling the D-STATCOM output current. The current controller has one zero and two poles. This type of controller is also known as Type-2 controller. The procedure to tune the controller is explained. The Conservative Power Theory (CPT) is used to compute the reactive power of the loads. A case study shows the behavior of the D-STACOM during initialization, during load transitions and during steady-state conditions. The results show the efficacy of the proposed D-STATCOM. © 2020 IEEE.

关键词： Static synchronous compensators

Decoherence limiting the cost to simulate an anharmonic oscillator

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Physical Review A 2023年第6期108卷 062219-062219页

作者： Tzula B. Propp Sayonee Ray John B. DeBrota Tameem Albash Ivan H. Deutsch Center for Quantum Information & Control University of New Mexico Albuquerque New Mexico 87131 USA Department of Physics and Astronomy University of Waterloo Ontario N2L 3G1 Canada Department of Electrical and Computer Engineering University of New Mexico Albuquerque New Mexico 87131 USA Department of Physics and Astronomy University of New Mexico Albuquerque New Mexico 87131 USA

We study how decoherence increases the efficiency with which we can simulate the quantum dynamics of an anharmonic oscillator governed by the Kerr effect. As decoherence washes out the fine-grained sub-Planck structure associated with phase-space quantum interference in the closed quantum system, open quantum dynamics can be more efficiently simulated using a coarse-grained finite-difference numerical integration. We tie this to the way in which decoherence recovers the semiclassical truncated Wigner approximation, which strongly differs from the exact closed-system dynamics at times when quantum interference leads to cat states and more general superpositions of coherent states. The regression in quadrature measurement statistics to semiclassical dynamics becomes more pronounced as the initial amplitude of the oscillator grows, with implications for the quantum advantage that might be accessible as system size grows in noisy quantum devices. Lastly, we show that this regression does not have the form of a convex noise model, such as for a depolarizing noise channel. Instead, closed quantum system effects interact with the open-system effects, giving rise to distinct open-system behavior.

关键词： Cavity quantum electrodynamics Open quantum systems & decoherence computational complexity Phase space dynamics Semiclassical methods

Nanoplasmonic magneto-optical isolator [Invited]

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Chinese Optics Letters 2021年第8期19卷 130-137页

作者： Vahid Foroughi Nezhad Chenglong You Georgios Veronis School of Electrical Engineering and Computer Science Louisiana State UniversityBaton RougeLouisiana 70803USA Center for Computation and Technology Louisiana State UniversityBaton RougeLouisiana 70803USA Department of Physics and Astronomy Louisiana State UniversityBaton RougeLouisiana 70803USA

We introduce a nanoplasmonic isolator that consists of a cylindrical resonator placed close to a metal-dielectric-metal(MDM) waveguide. The material filling the waveguide and resonator is a magneto-optical(MO) material, and the structure is under an externally applied static magnetic field. We theoretically investigate the properties of the structure and show that the cavity mode without MO activity splits into two modes when the MO activity is present. In addition, we find that the presence of the MDM waveguide leads to a second resonance due to the geometrical asymmetry caused by the existence of the waveguide. We also show that, when MO activity is present, the cavity becomes a traveling wave resonator. Thus, the transmission of the structure depends on the direction of the incident light, and the proposed structure operates as an optical isolator.

关键词： plasmonics metal optics magneto-optic systems

IF: Iterative Fractional Optimization 29

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IF: Iterative Fractional Optimization

29th European Symposium on Artificial Neural Networks, computational Intelligence and Machine Learning, ESANN 2021

作者： Chatterjee, Sarthak Das, Subhro Pequito, Sérgio Department of Electrical Computer and Systems Engineering Rensselaer Polytechnic Institute TroyNY United States MIT-IBM Watson AI Lab IBM Research CambridgeMA United States Delft Center for Systems and Control Delft University of Technology Netherlands

ISBN: (纸本)9782875870827

Most optimization problems lack closed-form solutions of the argument that minimizes a given function, and even if these were available it might be prohibitive to compute it. As such, we rely on iterative numerical algorithms to find an approximate solution. In this paper, we propose to leverage fractional calculus in the context of time series analysis methods to devise a new iterative algorithm. Specifically, we propose to leverage autoregressive fractional-order integrative moving average time series, whose coefficients encode a proxy for local spatial information. We provide evidence that our algorithm is efficient and particularly suitable for cases where the Hessian is ill-conditioned. © 2021 ESANN Intelligence and Machine Learning. All rights reserved.

关键词： Time series analysis

Detailed Investigation of Bio-Foam Characteristics of Piggery Wastewater Reveals Novel Foaming Mechanisms

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SSRN

SSRN 2023年

作者： Cheng, Peijin Zhang, Jianming Zhang, Kaiji Liu, Yang Xu, Xiangyang Zhu, Liang Institute of Environment Pollution Control and Treatment Department of Environmental Engineering Zhejiang University Hangzhou310058 China Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety Hangzhou310058 China Zhejiang Provincial Engineering Laboratory of Water Pollution Control Hangzhou310058 China Hangzhou Xiaokai Technology Co. Ltd. Hangzhou310000 China Innovation Center of Yangtze River Delta Zhejiang University Jiashan314100 China Department of Electrical and Computer Engineering Samueli School of Engineering University of California Los AngelesCA United States Department of Environmental Engineering Zhejiang University No. 866 Yuhangtang Road Hangzhou310058 China

Biological foam has seriously troubled the wastewater treatment process and brings major challenges to effluent quality, process efficiency, and operation safety. This study systematically analyzed bio-foam characteristics from three piggery wastewater treatment stations to reveal potential foaming mechanisms. The low surface tension for piggery wastewater led to strong foaming capacity, and high viscosity and Zeta potential contributed to foam stability. The long-chain fatty acids (LCFAs) in wastewater were proved to be the key components responsible for foaming: the decrease of surface tension caused by LCFAs directly induced strong foaming ability (physicochemical path);moreover, LCFAs favored the enrichment of non-filamentous foam-related microbes like Hydrogenophaga and Pseudomonas to secrete extracellular polymeric substances, increasing the viscosity and Zeta potential to maintain foam stability (biological paths). Based on the revealed foaming mechanism dominated by LCFAS, this study provided novel insight and valuable guidance for the efficient and safe treatment of piggery wastewater. © 2023, The Authors. All rights reserved.

关键词： Surface tension

Effective Two-Stage Double Auction for Dynamic Resource Trading in Edge Networks via Overbooking

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arXiv 2025年

作者： Wu, Sicheng Liwang, Minghui Wang, Deqing Wang, Xianbin Wu, Chao Tang, Junyi Li, Li Jiao, Zhenzhen The School of Informatics Xiamen University Fujian China The Department of Control Science and Engineering The National Key Laboratory of Autonomous Intelligent Unmanned Systems Tongji University Shanghai China Frontiers Science Center for Intelligent Autonomous Systems Ministry of Education Tongji University Shanghai China The Department of Electrical and Computer Engineering Western University ON Canada The School of Public Affairs Zhejiang University Hangzhou310027 China School of Information Science and Engineering Lanzhou University Lanzhou China The iF-Labs Beijing Teleinfo Technology Co. Ltd. CAICT China

To facilitate responsive and cost-effective computing resource scheduling and service delivery over edge-assisted mobile networks, this paper investigates a novel two-stage double auction methodology via utilizing an interesting idea of resource overbooking to overcome dynamic and uncertain nature from edge servers (sellers) and demand from mobile devices (as buyers). The proposed auction integrates multiple essential factors such as social welfare maximization and decision-making latency (e.g., the time for determining winning seller-buyer pairs) reduction, by introducing a stagewise strategy: an overbooking-driven pre-double auction (OPDAuction) for determining long-term cooperations between sellers and buyers before practical resource transactions as Stage I, and a real-time backup double auction (RBDAuction) for handling residual resource demands during actual transactions. In particular, by applying a proper overbooking rate, OPDAuction helps with facilitating trading contracts between appropriate sellers and buyers as guidance for future transactions, by allowing the booked resources to exceed supply. Then, since pre-auctions may cause risks, our RBDAuction adjusts to real-time market changes, further enhancing the overall social welfare. More importantly, we offer an interesting view to show that our proposed two-stage auction can support significant design properties such as truthfulness, individual rationality, and budget balance. Through extensive experiments, we demonstrate good performance in social welfare, time efficiency, and computational scalability, outstripping conventional methods in dynamic edge computing settings. Copyright © 2025, The Authors. All rights reserved.

关键词： Budget control