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Multilinear state space system identification with matrix product operators

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IFAC-PapersOnLine 2018年第15期51卷 640-645页

作者： Batselier, Kim Ko, Ching-Yun Phan, Anh-Huy Cichocki, Andrzej Wong, Ngai Electrical and Electronic Engineering Department The University of Hong Kong Hong Kong Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow Russia Systems Research Institute Polish Academy of Science Warsaw Poland

In this article, we introduce a matrix product operator, also called tensor train matrix, representation of discrete-time multilinear state space models and develop a corresponding system identification method. Using matrix product operators allows us to store the exponential number of model coefficients with a linear storage complexity. The derived system identification algorithm estimates the matrix product operator of the multilinear state space model directly from the measured data. This results in lower computational complexity compared to traditional nonlinear optimization methods. The effectiveness of our proposed model and method is demonstrated by a numerical experiment, where the identification of a degree-16 multilinear state space system in MATLAB on a standard desktop computer takes about 8 minutes with a relative validation error of 0.003%. © 2018

关键词： Matrix algebra

Magnetic-resonance-based electrical property mapping using global maxwell tomography with an 8-channel head coil at 7 Tesla: A simulation study

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arXiv 2020年

作者： Giannakopoulos, Ilias I. Serrallés, José E.C. Daniel, Luca Sodickson, Daniel K. Polimeridis, Athanasios G. White, Jacob K. Lattanzi, Riccardo Skoltech Center for Computational Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow143026 Russia Research Laboratory of Electronics Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology CambridgeMA United States Department of Radiology New York University School of Medicine New YorkNY United States Q Bio CA94063 United States

Objective: Global Maxwell Tomography (GMT) is a recently introduced volumetric technique for noninvasive estimation of electrical properties (EP) from magnetic resonance measurements. Previous work evaluated GMT using ideal radiofrequency (RF) excitations. The aim of this simulation study was to assess GMT performance with a realistic RF coil. Methods: We designed a transmit-receive RF coil with 8 decoupled channels for 7T head imaging. We calculated the RF transmit field (B1+) inside heterogeneous head models for different RF shimming approaches, and used them as input for GMT to reconstruct EP for all voxels. Results: Coil tuning/decoupling remained relatively stable when the coil was loaded with different head models. Mean error in EP estimation changed from 7.5% to 9.5% and from 4.8% to 7.2% for relative permittivity and conductivity, respectively, when changing head model without re-tuning the coil. Results slightly improved when an SVD-based RF shimming algorithm was applied, in place of excitation with one coil at a time. Despite errors in EP, RF transmit field (B1+) and absorbed power could be predicted with less than 0.5% error over the entire head. GMT could accurately detect a numerically inserted tumor. Conclusion: This work demonstrates that GMT can reliably reconstruct EP in realistic simulated scenarios using a tailored 8-channel RF coil design at 7T. Future work will focus on construction of the coil and optimization of GMT's robustness to noise, to enable in-vivo GMT experiments. Significance: GMT could provide accurate estimations of tissue EP, which could be used as biomarkers and could enable patient-specific estimation of RF power deposition, which is an unsolved problem for ultrahigh-field magnetic resonance imaging. Copyright © 2020, The Authors. All rights reserved.

关键词： Integral equations

Optimization-based approach to the calibration of mesoscale mechanical models for carbon nanotube systems

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arXiv 2019年

作者： Petrov, Vitaly Ostanin, Igor Zhilyaev, Petr Center for Design Manufacturing and Materials Skolkovo Institute of Science and Technology Moscow Russia Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow Russia

A new mesoscale mechanical model, describing elastic interactions in carbon nanotubes (CNT) and other nanofilaments, is proposed. Functional form of the developed model is based on enhanced vector model (EVM) that describes basic types of bond deformations: tension, torsion, bending and shear. Calibration of bond stiffnesses is performed by adjusting EVM parameters to reproduce both CNT's deformation energies and shape observed in a full-atomistic simulation. The parameters obtained are compared with the ones obtained from Euler-Bernoulli beam theory considerations. It is found that after certain critical length of a tested CNT specimen its stiffness parameters become length-independent and can be used in mesoscale simulations of CNTs of arbitrary length. Copyright © 2019, The Authors. All rights reserved.

关键词： Carbon nanotubes

AA-ICP: Iterative closest point with anderson acceleration

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AA-ICP: Iterative closest point with anderson acceleration

2018 IEEE International Conference on Robotics and Automation, ICRA 2018

作者： Pavlov, Artem L. Ovchinnikov, Grigory W.V. Derbyshev, Dmitry Yu. Tsetserukou, Dzmitry Oseledets, Ivan V. Skolkovo Institute of Science and Technology Skolkovo Innovation Center Space Center Moscow143026 Russia Skolkovo Institute of Science and Technology Computational and Data-Intensive Science and Engineering Russia Moscow Institute of Physics and Technology Russia Skolkovo Institute of Science and Technology Space Center Russia Skolkovo Institute of Science and Technology Center for Computational and Data-Intensive Science and Engineering Russia

ISBN: (纸本)9781538630815

Iterative Closest Point (ICP) is a widely used method for performing scan-matching and registration. Being simple and robust, this method is still computationally expensive and may be challenging to use in real-time applications with limited resources on mobile platforms. In this paper we propose a novel effective method for acceleration of ICP which does not require substantial modifications to the existing code. This method is based on an idea of Anderson acceleration which is an iterative procedure for finding a fixed point of contractive mapping. The latter is often faster than a standard Picard iteration, usually used in ICP implementations. We show that ICP, being a fixed point problem, can be significantly accelerated by this method enhanced by heuristics to improve overall robustness. We implement proposed approach into Point Cloud Library (PCL) and make it available online. Benchmarking on the real-world data fully supports our claims. © 2018 IEEE.

关键词： Iterative methods

Author Correction: Employing fingerprinting of medicinal plants by means of LC-MS and machine learning for species identification task

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Scientific reports 2020年第1期10卷 11482页

作者： Pavel Kharyuk Dmitry Nazarenko Ivan Oseledets Igor Rodin Oleg Shpigun Andrey Tsitsilin Mikhail Lavrentyev Skolkovo Institute of Science and Technology Center for Computational and Data-Intensive Science and Engineering Moscow 143026 Russia. kharyuk.pavel@***. Institute of Numerical Mathematics of the Russian Academy of Sciences Moscow 119991 Russia. kharyuk.pavel@***. Lomonosov Moscow State University Faculty of Chemistry Moscow 119991 Russia. dmitro.nazarenko@***. Skolkovo Institute of Science and Technology Center for Computational and Data-Intensive Science and Engineering Moscow 143026 Russia. Institute of Numerical Mathematics of the Russian Academy of Sciences Moscow 119991 Russia. Lomonosov Moscow State University Faculty of Chemistry Moscow 119991 Russia. All-Russian Research Institute of Medicinal and Aromatic Plants (VILAR) Moscow 117216 Russia. Saratov State University Department of Botanics and Ecology Saratov 410012 Russia.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

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Model Predictive Path Integral Control for Car Driving with Autogenerated Cost map Based on Prior Map and Camera Image

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Model Predictive Path Integral Control for Car Driving with ...

International Conference on Intelligent Transportation

作者： Alexander Buyval Aidar Gabdullin Konstantin Sozykin Alexandr Klimchik Center for Technologies in Robotics and Mechatronics Components Innopolis University Innopolis Russia Skolkovo Institute of Science and Technology (Skoltech) Center for Computational and Data-Intensive Science and Engineering (CDISE) Russia

ISBN: (纸本)9781538670255

Model Predictive Path Integral (MPPI) algorithm is an efficient approach to control an autonomous car. However, it requires a cost map. Preparing a cost map in advance is a task that can be completed only for a static closed unchanging environment, but impossible for real city conditions where the environment is dynamic. In this work, we present a method for automatic creation of the cost map based on map data and image from a camera mounted on a self-driving car. The described approach was tested on the Kia Soul car.

关键词： Cameras Automobiles Fires Roads Image segmentation Prediction algorithms Heuristic algorithms

The Multiband Imaging Survey for High-Alpha PlanetS (MISHAPS) I: Preliminary Constraints on the Occurrence Rate of Hot Jupiters in 47 Tucanae

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arXiv 2024年

作者： Crisp, Alison L. Klüter, Jonas Newman, Marz L. Penny, Matthew T. Beatty, Thomas G. Cleeves, L. Ilsedore Collins, Karen A. Johnson, Jennifer A. Johnson, Marshall C. Lund, Michael B. Martínez-Vázquez, Clara E. Ness, Melissa K. Rodriguez, Joseph E. Siverd, Robert Stevens, Daniel J. Villanueva, Steven Ziegler, Carl Department of Physics & Astronomy Louisiana State University Baton RougeLA70803 United States Department of Astronomy The Ohio State University ColumbusOH43210 United States Center for Computation & Technology Louisiana State University Baton RougeLA70803 United States Department of Astronomy University of Wisconsin – Madison MadisonWI53706 United States Department of Astronomy University of Virginia CharlottesvilleVA22904 United States Department of Chemistry University of Virginia CharlottesvilleVA22904 United States Harvard-Smithsonian Center for Astrophysics CambridgeMA02138 United States Center for Cosmology & Astro Particle Physics The Ohio State University ColumbusOH43210 United States NASA Exoplanet Science Institute California Institute of Technology PasadenaCA91125 United States Gemini North Observatory NOIRLab HiloHI96720 United States Department of Astronomy Columbia University New YorkNY10027 United States Simons Center for Computational Astrophysics Flatiron Institute New YorkNY10004 United States Center for Data Intensive and Time Domain Astronomy Department of Physics & Astronomy Michigan State University East LansingMI48824 United States Institute for Astronomy University of Hawai’i at Mānoa HonoluluHI96822 United States Department of Physics & Astronomy University of Minnesota – Duluth DuluthMN55812 United States Exoplanets & Stellar Astrophysics Laboratory NASA Goddard Space Flight Center GreenbeltMD20771 United States Department of Physics Engineering & Astronomy Stephen F. Austin State University NacogdochesTX75962 United States

The first generation of transiting planet searches in globular clusters yielded no detections, and in hindsight, only placed occurrence rate limits slightly higher than the measured occurrence rate in the higher-metallicity Galactic thick disk. To improve these limits, we present the first results of a new wide field search for transiting hot Jupiters in the globular cluster 47 Tucanae. We have observed 47 Tuc as part of the Multiband Imaging Survey for High-Alpha Planets (MISHAPS). Using 24 partial and full nights of observations taken with the Dark Energy Camera on the 4-m Blanco telescope at CTIO, we perform a search on 19,930 stars in the outer regions of the cluster. Though we find no clear planet detections, by combining our result with the upper limit enabled by Gilliland et al.’s (2000) Hubble search for planets around an independent sample of 34,091 stars in the inner cluster, we place the strongest limit to date on hot Jupiters with periods of 0.8 ≤ P ≤ 8.3 days and 0.5 RJup ≤ RP ≤ 2.0 RJup of fHJ © 2024, CC BY.

关键词： Stars

DronePick: Object picking and delivery teleoperation with the drone controlled by a wearable tactile display

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arXiv 2019年

作者： Ibrahimov, Roman Tsykunov, Evgeny Shirokun, Vladimir Somov, Andrey Tsetserukou, Dzmitry Intelligent Space Robotics Laboratory Skolkovo Institute of Science and Technology Moscow Russia Center for Computational and Data-Intensive Science and Engineering Skolkovo Institute of Science and Technology Moscow Russia

We report on the teleoperation system DronePick which provides remote object picking and delivery by a human-controlled quadcopter. The main novelty of the proposed system is that the human user continuously gets the visual and haptic feedback for accurate teleoperation. DronePick consists of a quadcopter equipped with a magnetic grabber, a tactile glove with finger motion tracking sensor, hand tracking system, and the Virtual Reality (VR) application. The human operator teleoperates the quadcopter by changing the position of the hand. The proposed vibrotactile patterns representing the location of the remote object relative to the quadcopter are delivered to the glove. It helps the operator to determine when the quadcopter is right above the object. When the "pick" command is sent by clasping the hand in the glove, the quadcopter decreases its altitude and the magnetic grabber attaches the target object. The whole scenario is in parallel simulated in VR. The air flow from the quadcopter and the relative positions of VR objects help the operator to determine the exact position of the delivered object to be picked. The experiments showed that the vibrotactile patterns were recognized by the users at the high recognition rates: the average 99% recognition rate and the average 2.36s recognition time. The real-life implementation of DronePick featuring object picking and delivering to the human was developed and tested. Copyright © 2019, The Authors. All rights reserved.

关键词： Remote control

An adaptive algorithm for quantum circuit simulation

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arXiv 2019年

作者： Schutski, Roman Oseledets, Ivan Lykov, Danil Center for Computational and Data-Intensive Science and Engineering Skoltech Skolkovo Innovation Center Moscow Region121205 Moscow Institute of Physics and Technology Dolgoprudny Moscow Region141701

Efficient simulation of quantum computers is essential for the development and validation of near-term quantum devices and the research on quantum algorithms. Up to date, two main approaches to simulation were in use, based on either full state or single amplitude evaluation. We propose an algorithm that efficiently interpolates between these two possibilities. Our approach elucidates the connection between quantum circuit simulation and partial evaluation of expressions in tensor algebra. Copyright © 2019, The Authors. All rights reserved.

关键词： Circuit simulation