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Connected Components-based Colour Image Representations of Vibrations for a Two-stage Fault Diagnosis of Roller Bearings Using Convolutional Neural Networks

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Chinese Journal of Mechanical Engineering 2021年第3期34卷 73-93页

作者： Hosameldin o.A.Ahmed Asoke K Nandi Department of Electronic and Electrical Engineering Brunel University LondonUxbridge UB83PHUK School of Mechanical Engineering Xi’an Jiaotong UniversityXi’anChina

Roller bearing failure is one of the most common faults in rotating *** techniques for bearing fault diagnosis based on faults feature extraction have been *** feature extraction from fault signals requires expert prior information and human ***,deep learning algorithms have been applied extensively in the condition monitoring of rotating machines to learn features automatically from the input *** its robust performance in image recognition,the convolutional neural network(CNN)architecture has been widely used to learn automatically discriminative features from vibration images and classify health *** paper proposes and evaluates a two-stage method RGBVI-CNN for roller bearings fault *** first stage in the proposed method is to generate the RGB vibration images(RGBVIs)from the input vibration *** begin this process,first,the 1-D vibration signals were converted to 2-D grayscale vibration *** the conversion was completed,the regions of interest(RoI)were found in the converted 2-D grayscale vibration ***,to produce vibration images with more discriminative characteristics,an algorithm was applied to the 2-D grayscale vibration images to produce connected components-based RGB vibration images(RGBVIs)with sets of colours and texture *** the second stage,with these RGBVIs a CNN-based architecture was employed to learn automatically features from the RGBVIs and to classify bearing health *** cases of fault classification of rolling element bearings are used to validate the proposed *** results of this investigation demonstrate that RGBVI-CNN can generate advantageous health condition features from bearing vibration signals and classify the health conditions under different working loads with high ***,several classification models trained using RGBVI-CNN offered high performance in the testing results of the overall classification accura

关键词： Bearing fault diagnosis Image representation of vibrations Deep learning Convolutional neural networks

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The amazing world of light nuclei

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Science Bulletin 2024年第21期69卷 3303-3304页

作者： AslıKuşoğlu Department of Physics Faculty of ScienceIstanbul UniversityVezneciler/Fatih34134 IstanbulTurkey

Light nuclei are few-body quantal systems and historically their spectra were theﬁrst to be studied *** a recent review,the existing experimental data from the stable N¼Z doubly-odd nuclei and spectroscopic studies have been discussed,as well as the b decay of the corresponding isobaric multiplets[1].The description of nuclear many-body systems derived fromﬁrst principles remains one of the most challenging research areas over the past decades because of the complex nature and limited knowledge of fundamental forces among nucleons,emerging from either meson-exchange theory or quantum chromodynamics(QCD).

关键词： meson decay spectroscopic

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Measuring the Adiabatic Ignition Delay of n-Pentane Mixture using Rapid Compression Machine

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Journal of Thermal Science 2022年第2期31卷 552-560页

作者： J.A.Piehl o.Samimi-Abianeh Mechanical Engineering Department of Wayne State University DetroitMIUnited States of America

Recent combustion research has focused on low temperature combustion to meet engine emission regulations and to advance the development of low temperature homogenous compression ignition *** studies in this temperature regime are primarily performed by Rapid Compression Machines(RCMs)which are sensitive to the heat transfer characteristics of the experimental *** are widely used to measure autoignition data such as ignition delay and species *** ignition delays from RCMs are typically reported at an adiabatic condition;however,this assumption may produce a systematic error in ignition delay measurement as heat transfer is observed to reduce the pressure and temperature during the autoignition process,e.g.,a longer ignition delay has a greater pressure and temperature *** are custom built and have unique design characteristics that affect the heat transfer during the autoignition *** addition,depending on the diluent composition(e.g.,helium versus nitrogen or argon),different heat transfer characteristics are *** a result,autoignition results at similar conditions may vary from facility to facility or depending on the used *** dependency of the measured data on the used facility or diluent may produce uncertainty in the data which impact the development of high-fidelity combustion *** this work,a new method is developed and utilized to eliminate heat transfer from the ignition delay *** evaluate the new method,the autoignition of n-pentane mixtures in the low temperature regime were investigated using an *** vary the heat transfer,the compression ratio of the RCM was changed and the ignition delays were measured at similar pressure and temperature *** tests were performed at an equivalence ratio of approximately one and nitrogen and argon as *** applying the new method,the effect of heat transfer on the ignition delays were eliminated successfully and ignitio

关键词： heat transfer Rapid Compression Machine(RCM) n-pentane autoignition ignition delay

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Synthesis and Some Properties of Metal organic Chemical Vapour Deposited Molybdenum oxysulphide Thin Films

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Journal of Materials Science & Technology 2010年第6期26卷 552-557页

作者： B.olofinjana G.o.Egharevba M.A.Eleruja C.Jeynes A.V.Adedeji o.o.Akinwunmi B.A.Taleatu C.U.Mordi E.o.B.Ajayi Department of Physics Obafemi Awolowo UniversityIle-IfeNigeria Department of Chemistry Obafemi Awolowo UniversityIle-IfeNigeria Department of Electronic and Electrical Engineering University of SurreyGuildfordSurrey GU2 5XHUK Department of Chemistry and Physics Elizabeth City State UniversityElizabeth CityNC 27909USA

Molybdenum oxodithiocarbamate was prepared as thin films which were deposited on sodalime glass a single solid source precursor for molybdenum oxysulphide substrates using metal organic chemical vapour deposition （MoCVD） technique at a temperature of 420~C. Rutherford backscattering spectroscopy （RBS） was used to determine the elemental composition of the film which showed that the films contained large amounts of oxygen. The large amount of oxygen was attributed to the large abundance of oxygen in the starting material. A direct optical energy gap of 3.31 eV was obtained from the analysis of the absorption spectrum. The scanning electron microscopy （SEM） micrographs of the films showed that the films were continuous and porous. An estimated average size of the grains was below 5 #m. X-ray diffraction （XRD） showed that the deposited films were crystalline in nature.

关键词： Molybdenum oxodithiocarbamate Molybdenum oxysulphide Metal organic chemical vapour deposition (MoCVD) Thin film

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Simplification of Double Folding Model Calculations in Study of Interaction Between Two Deformed Nuclei

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Communications in Theoretical Physics 2010年第6期53卷 1140-1144页

作者： o.N.Ghodsi Science Faculty Departyment of Physics University of Mazandaran P.O.

The Double Folding （DF） model calculation of the internuclear potential in heavy-ion interactions when the participant nuclei are deformed in their ground states involves a six-dimensional integral. Using the multipole expansion in these calculations, the DF six-dimensional integral reduce to the sum of the products of three single-dimensional integrals. In this paper we have presented a procedure for the calculation of the radius dependent functions in the multipole expansion of the nuclear density and their Fourier transforms. We have also reduced the DF model integrals to the sum of the single dimensional integrals using the obtained relations for the radius dependent functions in the multipole expansion and their Fourier transforms.

关键词： double folding model deformed nuclei internuclear potential

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VARIoUS NoTIoNS oF oRTHoGoNALITY IN NoRMED SPACES

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Acta Mathematica Scientia 2013年第5期33卷 1387-1397页

作者： N.B.oKELo J.o.AGURE P.o.oLECHE School of Mathematics and Actuarial Science Jaramogi Oginga Odinga University of Science and Technology School of Mathematics Statistics and Actuarial Science Maseno University

In this paper, we present various notions and aspects of orthogonality in normed spaces. Characterizations and generalizations of orthogonality are also consid- ered. Results on orthogonality of the range and the kern... 详细信息

关键词： orthogonality normed space elementary operator

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Vibrational, rotational, and triaxiality features in extended o(6) dynamical symmetry of IBM using three-body interactions

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Nuclear Science and Techniques 2020年第5期31卷 44-56页

作者： A.M.Khalaf Azza o.El-Shal M.M.Taha M.A.El-Sayed Physics Department Faculty of ScienceAl-Azhar UniversityCairoEgypt Mathematics and Theoretical Physics Department Nuclear Research CenterAtomic Energy AuthorityCairo 13759Egypt

The shape transition between the vibrational U(5)and deformed c-unstable o(6)dynamical symmetries of sd interacting boson model has been investigated by considering a modified o(6)Hamiltonian,providing that the coefficients of the Casimir operator of o(5)are N-dependent,where N is the total number of *** modified o(6)Hamiltonian does not contain the number operator of the d boson,which is responsible for the vibrational *** addition,the deformation features can be achieved without using the SU(3)limit by adding to the o(6)dynamical symmetry the three-body interaction[QQQ]^(0),where Q is the o(6)symmetric quadrupole ***,triaxiality can be generated through the inclusion of the cubic d-boson interaction[d+d+d+]^(3)·∣ddd∣^(3).The classical limit of the potential energy surface(PES),which represents the expected value of the total Hamiltonian in a coherent state,is studied and *** modified o(6)model is applied to the even–even^124-132 Xe *** parameters for the Hamiltonian and the PESs are calculated using a simulated search program to obtain the minimum root mean square deviation between the calculated and experimental excitation energies and B(E2)values for a number of low-lying levels.A good agreement between the calculations and experiment results is found.

关键词： Nuclear structure Extended o(6)of IBM Three-body interactions Coherent state

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The inhibitive study of egg shell powder on uns n08904 austenitic stainless steel corrosion in chloride solution

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Defence Technology（防务技术） 2018年第5期14卷 463-468页

作者： o.Sanni A.P.I.Popoola o.S.I.Fayomi Tshwane University of Technology Department of Chemical Metallurgical and Materials Engineering

The effect of egg shell powder(ES) as an environmental friendly inhibitor was studied for its corrosion inhibitive tendency on N08904 austenitic stainless steel in simulated saline(3.5% NaCl) solution using potentiodynamic polarization, weight loss, and SEM/EDX at room temperature. The experimental data explained the effective performance of ES with values of 57%-100% inhibition efficiency, at 2 g-10 g inhibitor concentration from weight loss tests due to the inhibition of stainless steel. The electrochemical action was as a result of the ionized particles which inhibit the compound influencing the redox reaction mechanism causing surface corrosion. ES's best performance was achieved when 6 g of the inhibitor concentration was added to the saline medium. Corrosion rate value decreased progressively with the presence of inhibitor because of anions adsorption at the interface of the metal film. Corrosion potential(Ecorr) value was found to decrease from-0.3991 V to-0.3447 V in the presence of inhibitor at 2 g concentration, decreasing gradually to-0.2048 at 6 g inhibitor concentration. The compounds identified in the ES completely adsorbed onto the surface of stainless steel as observed from the EDX analysis. The ES adsorption on stainless steel surface obeyed Langmuir adsorption isotherm. A corroded morphology with pits was observed in the SEM results without ES which contrast the images obtained with the presence of ES.

关键词： Austenitic stainless steel Corrosion Inhibition Egg shell Chloride Langmuir

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Effect of thermal load on performance parameters of solar concentrating photovoltaic:High-efficiency solar cells

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Energy and Built Environment 2022年第2期3卷 201-209页

作者： Ali.o.M.Maka Tadhg S o’Donovan Institute of Mechanical Process and Energy EngineeringSchool of Engineering and Physical SciencesHeriot-Watt UniversityEdinburgh EH144ASUnited Kingdom

The triple-junction solar cell is designed to exploit a wide range of the solar spectrum *** triple-layers consisting of GaInP/GaInAs/Ge,it is monolithically stacked,leading to high conversion *** describe and understand it’s operating behaviour,this paper presents a performance analysis of a triple-junction solar cell,based on estimation modelling.A model was developed to determine the performance characteristic of the solar ***,the J-V curve is characterising the performance of solar cells,which used to optimise and improve the design of the *** has been discussed the effects of thermal load related to cell temperature increases on the cell’s operating performance *** temperature increases from 25 to 125℃ have resulted variances,which causes a significant decrease in efficiency to approximately−17%,open circuit voltage by−15%and fill factor by−4.5%.on the other hand,the current density slightly increased by+5.5%.Finally,ought to consider the thermal management while designing and developing solar CPV technology;therefore,it’s significant to improve cell efficiency and to maintain cell integrity from thermal damage.

关键词： Performance parameters Temperature rises Triple-junction solar cells Performance analysis Cell temperature

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Caregivers＇ Perceptions of Causes and Treatment of Fever and Diarrhea among Under-Fives in Ile Ife

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Journal of Pharmacy and Pharmacology 2018年第9期6卷 854-858页

作者： T. E. babalola K. T. Ijadunola T. T. oyetoke K. o. oyeniyi A. A. Shittu S. A. Salawu Department of Paediatrics and Child Health Obafemi Awolowo University Teaching Hospitals Complex Ile-Ife Osun State220005 Nigeria Department of Community Health Obafemi Awolowo University Teaching Hospitals Complex Ile-Ife Osun State 220005Nigeria Department of Paediatrics State Specialist Hospital Asubiaaro Osogbo Osun State 00176 Nigeria Department of Surgery University of llorin Teaching Hospital Ilorin Kwara State 23401 Nigeria Department of psychiatry Lagos University Teaching Hospital Idi-Araba Lagos 100254 Nigeria

Introduction： Fever and diarrhoea account for a significant portion of under-five mortality in Nigeria. This might be related to file perceptions of caregivers on the causes, which could influence file treatment they proffer. The study was conducted among caregivers in Ife central Local Government. Results： Most mothers perceived that fever could be caused by malaria, teething, hot weather, cough and that diarrhea could be caused by teething, eating contaminated food, drink and water, dirty environment and feeding bottles. Illness behavior was poor, as most waited at least one day after the onset of symptoms before taking any action. Choice of treatment was mostly influenced by health education messages received from health workers and mass media. Discussion and conclusions： Caregivers had a fairly correct perception of the causes of fever, but had incorrect perceptions of the causes of diarrhea. There is need to educate caregivers on the causes of diarrhea, and appropriate treatment measures.

关键词： Caregivers fever diarrhea perception

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