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Improved Bearing Fault Diagnosis by Feature Extraction Based on GLCM, Fusion of Selection Methods, and Multiclass-Naïve Bayes Classification

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Journal of Signal and Information Processing 2021年第4期12卷 71-85页

作者： Mireille Pouyap Laurent Bitjoka Etienne Mfoumou Denis Toko Energy Signal Imaging and Automation Laboratory (LESIA) University of Ngaoundere Yaounde Cameroon Division of Applied Research & Innovation Nova Scotia Community College Dartmouth Canada Department of Mechanical Engineering College of Technology University of Buea Buea Cameroon

The presence of bearing faults reduces the efficiency of rotating machines and thus increases energy consumption or even the total stoppage of the machine. It becomes essential to correctly diagnose the fault caused by the bearing. Hence the importance of determining an effective features extraction method that best describes the fault. The vision of this paper is to merge the features selection methods in order to define the most relevant featuresin the texture of the vibration signal images. In this study, the Gray Level Co-occurrence Matrix (GLCM) in texture analysis is applied on the vibration signal represented in images. Features selection based on the merge of PCA (Principal component Analysis) method and SFE (Sequential Features Extraction) method is done to obtain the most relevant features. The multiclass-Na?ve Bayesclassifier is used to test the proposed approach. The success rate of this classification is 98.27%. The relevant features obtained give promising results and are more efficient than the methods observed in the literature.

关键词： GLCM PCA SFE Naïve Bayes Relevant Features

Energy and spectral analysis of confined solar flares from radio and X-ray observations

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Research in Astronomy and Astrophysics 2021年第11期21卷 35-46页

作者： Cheng-Ming Tan Karl Ludwig Klein Yi-Hua Yan Satoshi Masuda Bao-Lin Tan Jing Huang Guo-Wu Yuan CAS Key Laboratory of Solar Activity National Astronomical Observatories of Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China Observatoire de Paris LESIA&Station de radioastronomie de Nanc¸ayUniv.PSLCNRSSorbonne Univ.Univ.de ParisUniv.d’Orl´eans5 place Jules JanssenF-92190 MeudonFrance Institute for Space-Earth Environmental Research Nagoya UniversityNagoya 464-8601Japan School of Information Science and Engineering Yunnan UniversityKunming 650091China

The energy and spectral shape of radio bursts may help us understand the generation mechanism of solar eruptions,including solar flares,coronal mass ejections,eruptive filaments,and various scales of *** different kinds of flares may have different characteristics of energy and spectral *** this work,we selected 10 mostly confined flare events during October 2014 to investigate their overall spectral behaviour and the energy emitted in microwaves by using radio observations from microwaves to interplanetary radio waves,and X-ray observations of GOES,RHESSI,and Fermi/*** found that:all the confined flare events were associated with a microwave continuum burst extending to frequencies of9.4~15.4 GHz,and the peak frequencies of all confined flare events are higher than 4.995 GHz and lower than or equal to 17 *** median value is around 9 *** microwave burst energy(or nuence)and the peak frequency are found to provide useful criteria to estimate the power of solar *** observations imply that the magnetic field in confined flares tends to be stronger than that in 412 flares studied by Nita et al.(2004).All 10 events studied did not produce detectable hard X-rays with energies above~300 keV indicating the lack of efficient acceleration of electrons to high energies in the confined flares.

关键词： Sun:solar flare Sun:radio burst Sun:energy Sun:spectral

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Full Image Inference Conditionally upon Available Pieces Transmitted into Limited Resources Context

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Journal of Signal and Information Processing 2021年第3期12卷 57-69页

作者： Rodrigue Saoungoumi-Sourpele Jean Michel Nlong David Jaurès Fotsa-Mbogne Jean-Robert Kala Kamdjoug Laurent Bitjoka Department of Mathematics and Computer Science ENSAI University of Ngaoundere Yaounde Cameroon Department of Mathematics and Computer Science Faculty of Science University of Ngaoundere Yaounde Cameroon GRIAGES Catholic University of Central Africa Yaounde Cameroon Energy Image Signal and Automation Laboratory (LESIA) ENSAI University of Ngaoundere Yaounde Cameroon

In a context marked by the proliferation of smartphones and multimedia applications, the processing and transmission of images have become a real problem. Image compression is the first approach to address this problem, it nevertheless suffers from its inability to adapt to the dynamics of limited environments, consisting mainly of mobile equipment and wireless networks. In this work, we propose a stochastic model to gradually estimate an image upon information on its pixels that are transmitted progressively. We consider this transmission as a dynamical process, where the sender pushes the data in decreasing significance order. In order to adapt to network conditions and performances, instead of truncating the pixels, we suggest a new method called Fast Reconstruction Method by Kalman Filtering (FRM-KF) consisting of<

关键词： Progressive Image Transmission Bitplane Coding Kalman Filtering Fast Reconstruction

Cortical Arousal Strategies in Left-Handers during the Aural Perception and Manual Playback of Mono-and Polyphonic Rhythmical Patterns

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Journal of Life Sciences 2012年第12期6卷 1408-1413页

作者： Pavlovych Olga Sergiyivna Morenko Alevtyna Grigorivna Kotyk Olena Adamivna Vlasjuk Svitlana Sergiyivna lesia Ukrainka Volyn National University Lutsk *** Ukraine

The actual purpose of this study is to establish the cortical arousal strategies (according to the power of the EEG (electroencephalogram) α-oscillations) during the aural perception as well as manual playback of mono- and polyphonic rhythmical patterns in men with left profile. The study involved 35 men from 19 to 21 years old with the left profile of the manual and aural asymmetries. EEG was recorded in the functional status of rest: during the aural perception and playback of mono- and polyphonic rhythmical patterns with the left and right hand fingers. The monophony in the rhythmical pattern sounding relative to monophonic patterns is followed by more expressed and widespread cortical processes of the EEG α-oscillation depression. Given patterns indicate a greater intensity of ascending nonspecific arousal strategies of data processing by men on conditions of the sound and harmonious complications of the pattern structure. The aural perception and playback of rhythmical patterns with both hands were accompanied by the increased significance of arousal processes in the right hemisphere. This may be due to the dominant role of the hemisphere during the formation of the innervation impacts on the left-hander"s neuro-motor apparatus. More differentiated changes in the cerebral cortex were installed during the left hand activation.

关键词：听觉感知左撇子播放手动韵律模式和弦皮层大脑皮质

Detecting exoplanets with FAST?

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Research in Astronomy and Astrophysics 2019年第2期19卷 71-76页

作者： Philippe Zarka Di Li Jean-Mathias Grie?meier Laurent Lamy Julien N.Girard Sbastien L.G.Hess T.Joseph W.Lazio Gregg Hallinan lesia CNRS – Observatoire de Paris National Astronomical Observatories Chinese Academy of Science CAS Key Laboratory of FAST National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Science University of Chinese Academy of Sciences LPC2E CNRS – Universit d'Orlans Universit Paris VII AIM/Irfu/SAp/CEA-Saclay Orme des Merisiers ONERA – DESP JPL–California Institute of Technology California Institute of Technology

We briefly review the various proposed scenarios that may lead to nonthermal radio emissions from exoplanetary systems(planetary magnetospheres, magnetosphere-ionosphere and magnetospheresatellite coupling, and star-planet interactions), and the physical information that can be drawn from their detection. The latter scenario is especially favorable to the production of radio emission above 70 MHz. We summarize the results of past and recent radio searches, and then discuss FAST characteristics and observation strategy, including synergies. We emphasize the importance of polarization measurements and a high duty-cycle for the very weak targets that radio-exoplanets prove to be.

关键词： plasmas radiation mechanisms:non-thermal methods:observational telescopes(radio) planets and satellites:magnetic fields radio continuum:planetary systems

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Accretion in strong field gravity with eXTP

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Science China(Physics,Mechanics & Astronomy) 2019年第2期62卷 45-73页

作者： Alessandra De Rosa Phil Uttley LiJun Gou Yuan Liu Cosimo Bambi Didier Barret Tomaso Belloni Emanuele Berti Stefano Bianchi Ilaria Caiazzo Piergiorgio Casella Marco Feroci Valeria Ferrari Leonardo Gualtieri Jeremy Heyl Adam Ingram Vladimir Karas FangJun Lu Bin Luo Giorgio Matt Sara Motta Joseph Neilsen Paolo Pani Andrea Santangelo XinWen Shu JunFeng Wang Jian-Min Wang YongQuan Xue YuPeng Xu WeiMin Yuan YeFei Yuan Shuang-Nan Zhang Shu Zhang Ivan Agudo Lorenzo Amati Nils Andersson Cristina Baglio Pavel Bakala Altan Baykal Sudip Bhattacharyya Ignazio Bombaci NiccolóBucciantini Fiamma Capitanio Riccardo Ciolfi Wei K.Cui Filippo D'Ammando Thomas Dauser Melania Del Santo Barbara De Marco Tiziana Di Salvo Chris Done Michal Dovciak Andrew C.Fabian Maurizio Falanga Angelo Francesco Gambino Bruce Gendre Victoria Grinberg Alexander Heger Jeroen Homan Rosario Iaria JiaChen Jiang ChiChuan Jin Elmar Koerding Manu Linares Zhu Liu Thomas J.Maccarone Julien Malzac Antonios Manousakis Frédéric Marin Andea Marinucci Missagh Mehdipour Mariano Méndez Simone Migliari Cole Miller Giovanni Miniutti Emanuele Nardini Paul T.O'Brien Julian P.Osborne Pierre Olivier Petrucci Andrea Possenti Alessandro Riggio Jerome Rodriguez Andrea Sanna LiJing Shao Malgosia Sobolewska Eva Sramkova Abigail L.Stevens Holger Stiele Giulia Stratta Zdenek Stuchlik Jiri Svoboda Fabrizio Tamburini Thomas M.Tauris Francesco Tombesi Gabriel Torok Martin Urbanec Frederic Vincent QingWen Wu Feng Yuan Jean J.M.in't Zand Andrzej A.Zdziarski XinLin Zhou INAF-Istituto di Astrofisica e Planetologie Spaziali Via Fosso del Cavaliere Anton Pannekoek Institute for Astronomy University of Amsterdam National Astronomical Observatories Chinese Academy of Science Institute of High Energy Physics Chinese Academy of Science Center for Field Theory and Particle Physics and Department of Physics Fudan University IRAP Universitéde ToulouseCNRSUPSCNES INAF-Osservatorio Astronomico di Brera Department of Physics and Astronomy The University of MississippiUniversity Dipartimento di Matematica e Fisica Universitàdegli studi Roma Tre University of British Columbia INAF-Osservatorio Astronomico di Roma INFN-Roma 2 c/o Dipartimento di Fisica II Universit?di Roma"Tor Vergata" Dipartimento di Fisica Universitàdegli Studi di Roma"La Sapienza"&Sezione INFN Roma1 Department of Physics University of OxfordClarendon Laboratory Astronomical Institute Academy of Sciences School of Astronomy and Space Science Nanjing University MIT Kavli Institute for Astrophysics and Space Research Institut für Astronomie und Astrophysik Eberhard Karls Universität Department of Physics Anhui Normal University Department of Astronomy and Institute of Theoretical Physics and Astrophysics Xiamen University CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of China Instituto de Astrofísica de Andalucia(CSIC) Glorieta de la Astronomía s/n INAF-Istituto di Astrofisica Spaziale e Fisica cosmica di Bologna Mathematical Sciences and STAG Research Centre University of Southampton New York University Abu Dhabi Institute of Physics and Research Centre for Computational Physics and Data Processing Faculty of Philosophy&ScienceSilesian University in OpavaíBezru?ovo nám. Department of Physics Middle East Technical University Department of Astronomy and Astrophysics Tata Institute of Fundamental Research Dipartimento di Fisica Universit?di Pisa&INFN INAF-Osservatorio Astrofisico di Arcetri INAF-Osservatorio Astronomico di Padova INFN-TIFPA Trento Ins

In this paper we describe the potential of the enhanced X-ray Timing and Polarimetry(eXTP) mission for studies related to accretion flows in the strong field gravity regime around both stellar-mass and supermassive black-holes. eXTP has the unique capability of using advanced "spectral-timing-polarimetry" techniques to analyze the rapid variations with three orthogonal diagnostics of the flow and its geometry, yielding unprecedented insight into the inner accreting regions, the effects of strong field gravity on the material within them and the powerful outflows which are driven by the accretion process.

关键词： X-ray black holes physics accretion

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The Giant Radio Array for Neutrino Detection(GRAND):Science and design

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Science China(Physics,Mechanics & Astronomy) 2020年第1期Mechanics & Astronomy) .卷 5-47页

作者： Jaime álvarez-Mu?iz Rafael Alves Batista Aswathi Balagopal V. Julien Bolmont Mauricio Bustamante Washington Carvalho Jr. Didier Charrier Isma?l Cognard Valentin Decoene Peter B.Denton Sijbrand De Jong Krijn D.De Vries Ralph Engel Ke Fang Chad Finley Stefano Gabici Quan Bu Gou Jun Hua Gu Claire Guépin Hong Bo Hu Yan Huang Kumiko Kotera Sandra Le Coz Jean-Philippe Lenain Guo Liang Léü Olivier Martineau-Huynh Miguel Mostafá Fabrice Mottez Kohta Murase Valentin Niess Foteini Oikonomou Tanguy Pierog Xiang Li Qian Bo Qin Duan Ran Nicolas Renault-Tinacci Markus Roth Frank G.Schr ?der Fabian Schüssler Cyril Tasse Charles Timmerman Matías Tueros Xiang Ping Wu Philippe Zarka Andreas Zech B.Theodore Zhang Jian Li Zhang Yi Zhang Qian Zheng Anne Zilles Departamento de Física de Partículas & Instituto Galego de Física de Altas Enerxías Universidad de Santiago de Compostela Instituto de Astronomia Geofísica e Ciências Atmosféricas Universidade de S?o Paulo Department of Physics—Astrophysics University of Oxford DWB Institute of Experimental Particle Physics (ETP) Karlsruhe Institute of Technology (KIT) Laboratoire de Physique Nucléeaire et de Hautes Energies (LPNHE) Sorbonne Université Université Paris Diderot Sorbonne Paris Cité Niels Bohr International Academy and DARK Niels Bohr Institute Discovery Center Niels Bohr Institute Center for Cosmology and Astro Particle Physics (CCAPP) & Department of Physics Ohio State University Universidade de Santiago de Compostela SUBATECH Institut Mines-Telecom Atlantique – CNRS/IN2P3 – Université de Nantes Laboratoire de Physique et Chimie de l’Environnement et de l’Espace LPC2E CNRS-Université d’Orléans Station de Radioastronomie de Nan?cay Observatoire de Paris Sorbonne Université UMR 7095 Institut d’Astrophysique de Paris Institute for Mathematics Astrophysics and Particle Physics (IMAPP) Radboud Universiteit Nationaal Instituut voor Kernfysica en Hoge Energie Fysica (NIKHEF) IIHE/ELEM Vrije Universiteit Brussel Institute for Nuclear Physics (IKP) Karlsruhe Institute of Technology (KIT) Einstein Fellow Stanford University Department of Astronomy University of Maryland Joint Space-Science Institute Oskar Klein Centre Stockholm University Department of Physics Stockholm University Astro Particule et Cosmologie (APC) Université Paris Diderot CNRS/IN2P3 CEA/Irfu Observatoire de Paris Institute of High Energy Physics Chinese Academy of Sciences National Astronomical Observatories Chinese Academy of Sciences School of Physical Science and Technology Xinjiang University Center for Particle and Gravitational Astrophysics Pennsylvania State University Department of Physics Pennsylvania State University Department of Astronomy & Astrophysics Pennsylvania State University LUTH Observatoire de Paris

The Giant Radio Array for Neutrino Detection（GRAND） is a planned large-scale observatory of ultra-high-energy（UHE） cosmic particles, with energies exceeding 10～8 Ge V. Its goal is to solve the long-standing mystery of the origin of UHE cosmic rays. To do this, GRAND will detect an unprecedented number of UHE cosmic rays and search for the undiscovered UHE neutrinos and gamma rays associated to them with unmatched sensitivity. GRAND will use large arrays of antennas to detect the radio emission coming from extensive air showers initiated by UHE particles in the atmosphere. Its design is modular: 20 separate, independent sub-arrays, each of 10000 radio antennas deployed over 10000 km2. A staged construction plan will validate key detection techniques while achieving important science goals early. Here we present the science goals, detection strategy, preliminary design, performance goals, and construction plans for GRAND.

关键词： radio telescopes neutrinos in astronomical observations cosmic rays in astronomical observations radiowave radiation: sources galactic and extragalactic cosmic rays

The Giant Radio Array for Neutrino Detection(GRAND):Science and design

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Science China(Physics,Mechanics & Astronomy) 2020年第1期63卷 1-43页

作者： Jaime Alvarez-Muniz Rafael Alves Batista Aswathi Balagopal V. Julien Bolmont Mauricio Bustamante Washington Carvalho Jr. Didier Charrier Ismael Cognard Valentin Decoene Peter B.Denton Sijbrand De Jong Krijn D.De Vries Ralph Engel Ke Fang Chad Finley Stefano Gabici Quan Bu Gou Jun Hua Gu Claire Guépin Hong Bo Hu Yan Huang Kumiko Kotera Sandra Le Coz Jean-Philippe Lenain Guo Liang Léü Olivier Martineau-Huynh Miguel Mostafá Fabrice Mottez Kohta Murase Valentin Niess Foteini Oikonomou Tanguy Pierog Xiang Li Qian Bo Qin Duan Ran Nicolas Renault-Tinacci Markus Roth Frank G.Schroder Fabian Schüssler Cyril Tasse Charles Timmerman Matías Tueros Xiang Ping Wu Philippe Zarka Andreas Zech B.Theodore Zhang Jian Li Zhang Yi Zhang Qian Zheng Anne Zilles Departamento de Fisica de Particulas&lnstituto Galego de Fisica de Altas Enerxias Universidad de Santiago de CompostelaSantiago de Compostela 15782Spain Instituto de Astronomia Geofisica e Ciencias AtmosfericasUniversidade de Sao PauloSao Paulo-SP 05508-090Brazil Department of Physics-Astrophysics University of OxfordDWBOxford 0X13RHUK Institute of Experimental Particle Physics(ETP) Karlsruhe Institute of Technology(KIT)Karlsru he D-76021Germany Laboratoire de Physique Nucleeaire et de Hautes Energies(LPNHE) Sorbonne UniversiteUniversite Paris DiderotSorbonne Paris CiteCNRS place Jussieu F-75252Paris Cedex 5France Niels Bohr International Academy and DARK Niels Bohr InstituteCopenhagen 2100Denmark Discovery Center Niels Bohr InstituteCopenhagen 2100Denmark Center for Cosmology and AstroParticle Physics(CCA.PP)&Department of Physics Ohio State UniversityColumbus OH 43210USA Universidade de Santiago de Compostela Santiago de Compostela 15782Spain 0SUBATECH Institut Mines-Telecom Atlantique-CNRS/IN2P3-Universite de NantesNantes 44300France Laboratoire de Physique et Chimie de KEnvironnement et de VEspace LPC2E CNRS-Universite d'Orleans Orleans F-45071France Station de Radioastronomie de Nancay Observatoire de ParisCNRS/INSU F-18330 NangayFrance Sorbonne Universite UMR 7095Institut d'Astrophysique de Paris98 bis bd AragoParis 75014France Institute for Mathematics Astrophysics and Particle Physics(IMAPP)Radboud UniversiteitNijmegen 6500Netherlands Nationaal Instituut voor Kemfysica en Hoge Energie Fysica(NIKHEF) Amsterdam NL-1009Netherlands IIHE/ELEM Vrije Universiteit BrusselPleinlaan 2Brussels 1050Belgium Institute for Nuclear Physics(IKP) Karlsruhe Institute of Technology(KIT)Karlsruhe D-76021Germany Einstein Fellow Stanford UniversityStanford CA 94305USA Department of Astronomy University of MarylandCollege Park MD 20742-2421USA Joint Space-Science Institute College Park MD 20742-2421USA Oskar Klein Centre Stockholm UniversityStockholm SE-10691Sweden Department of Phy

The Giant Radio Array for Neutrino Detection(GRAND)is a planned large-scale observatory of ultra-high-energy(UHE)cosmic particles,with energies exceeding 10~8 Ge *** goal is to solve the long-standing mystery of the origin of UHE cosmic *** do this,GRAND will detect an unprecedented number of UHE cosmic rays and search for the undiscovered UHE neutrinos and gamma rays associated to them with unmatched *** will use large arrays of antennas to detect the radio emission coming from extensive air showers initiated by UHE particles in the *** design is modular:20 separate,independent sub-arrays,each of 10000 radio antennas deployed over 10000 km^2.A staged construction plan will validate key detection techniques while achieving important science goals *** we present the science goals,detection strategy,preliminary design,performance goals,and construction plans for GRAND.

关键词： radio telescopes neutrinos in astronomical observations cosmic rays in astronomical observations radiowave radiation:sources galactic and extragalactic cosmic rays:galactic and extragalactic