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Scale-Covariant Theory of Gravitation Through Self-Similarity

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Chinese Physics Letters 2012年第5期29卷 33-36页

作者： jose Antonio Belinchon Department of Nuclear Molecular and Atomic PhysicsUniversity Complutense of MadridE-28040Spain

We study the scale-covariant theory of gravitation proposed by Canuto under the self-similar *** considering the matter collineation approach,we deduce the form of the main quantities and obtain some restrictions on the behavior of the gauge function,φ(t).We apply the obtained results to study the Bianchi I,Ⅶo,Ⅸ and Kantowsky Sachs models,and arrive at the conclusion that instead of considering a varying G theory,the solution is only valid for a particular value of the parameter of the equation of state,γ,.This leads us to obtain φ(t) =const,and by taking into account the external condition,Gφ2 =const,we may arrive at the conclusion that G=***,all the obtained solutions are the same as the ones obtained in the framework of general relativity.

关键词： const conclusion considering

High-repetition-rate source of nanosecond duration kA-current pulses driven by relativistic laser pulses

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High Power Laser Science and Engineering 2024年第3期 111-120页

作者： Michael Ehret Jakub Cikhardt Philip Wykeham Bradford Iuliana-Mariana Vladisavlevici Tomas Burian Diego de Luis jose Luis Henares Rubén Hernández Martín Jon Imanol Api?aniz Roberto Lera JoséAntonio Pérez-Hernández Jo?o Jorge Santos Giancarlo Gatti Centro de Láseres Pulsados (CLPU) Czech Technical University in Prague Faculty of Electrical Engineering Univ. Bordeaux-CNRS-CEA Centre Lasers Intenses et Applications (CELIA) Department of Radiation and Chemical Physics FZU-Institute of Physics of the Czech Academy of Sciences Univ. Bordeaux-CNRS-CEA Centre Lasers Intenses et Applications (CELIA)

We report the first high-repetition-rate generation and simultaneous characterization of nanosecond-scale return currents of kA-magnitude issued by the polarization of a target irradiated with a PW-class high-repetition-rate titanium:sapphire laser system at relativistic *** present experimental results obtained with the VEGA-3 laser at intensities from5×1018to 1.3×1020W cm-2.A non-invasive inductive return-current monitor is adopted to measure the derivative of return currents of the order of kA ns-1and analysis methodology is developed to derive return *** compare the current for copper,aluminium and Kapton targets at different laser *** data show the stable production of current peaks and clear prospects for the tailoring of the pulse shape,which is promising for future applications in highenergy-density science,for example,electromagnetic interference stress tests,high-voltage pulse response measurements and charged particle beam *** compare the target discharge of the order of hundreds of nC with theoretical predictions and a good agreement is found.

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Microwave photonics

Science China(Information Sciences) 2022年第12期65卷 49-112页

作者： Jianping YAO jose CAPMANY Microwave Photonics Research Laboratory School of Electrical Engineering and Computer Science University of Ottawa ITEAM Research Institute Universitat Politècnica de València iPronics Programmable Photonics

Microwave photonics, an interdisciplinary field that combines microwave engineering and photonic technology for the generation, transmission, processing, and control of microwave signals, to take advantage of the broad bandwidth, high frequency, and low loss offered by modern photonics, has been intensively researched for the last few decades, and numerous solutions have been proposed and demonstrated. In this article, an overview about microwave photonics is provided which covers the basic concepts of microwave photonics, photonic-assisted microwave signal generation, photonic-assisted microwave signal processing, and true time delay beamforming. The implementation of microwave photonic systems based on photonic integrated circuits is also reviewed, including the design, fabrication, and material platforms, application-specific photonic integrated circuits for microwave photonics, and programmable integrated microwave *** challenges and future applications of microwave photonics are also discussed.

关键词： microwave photonics photonic integrated circuits microwave photonic link microwave photonic signal processor optoelectronic oscillator radio over fiber

Single-shot incoherent optical processing of microwave signals： opening the path to low cost high performance analog photonics

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Science Bulletin 2017年第9期62卷 652-653页

作者： jose Capmany ITEAM Research Institute Universitat Politecnica de Valencia Camino de Vera s/n 46022 Valencia Spain

Incoherent optical processing of microwave signals,where low-coherence broadband light sources are employed instead of costly mode locked lasers,has attracted great interest thanks to its wide applications in microwav... 详细信息

关键词： Single-shot incoherent optical processing of microwave signals:opening the path to low cost high performance analog photonics high MZM SNR mode SLD

Application of micro-morphology in the physical characterization of urban road dust

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Particuology 2021年第1期19卷 146-155页

作者： Jithin jose B.Srimuruganandam School of Civil Engineering Vellore Institute of TechnologyVellore 632014Tamil NaduIndia

Urban road dust was collected from Vellore City,Tamil Nadu,India,and *** electron microscopy(SEM)was used to examine road dust from nine sampling locations in the study *** image analysis was used to identify various shape factors of collected dust *** equivalent spherical diameter of most particles was between 10μm and 30μ*** particles had greater concentrations at locations with higher traffic *** were categorized into four classes based on their shape factors,viz.,spherical,mineral,elongated,or *** particles had the smallest mean equivalent diameter(1.95μm)and mineral particles had the largest diameter(33.3μm).Spherical particles made up the smallest portion of road dust(0-12%)in the study region and mineral particles made up the largest(45-65%).Elongated and irregular particles,each made up 23-30%of road *** dispersive X-ray spectroscopy analysis was used to identify the elemental composition of dust *** particles were mostly from combustion sources and mineral particles were largely of crustal *** individual source was found for irregular and elongated *** debris was the major source of irregular particles.

关键词： Road dust Scanning electron microscopy Shape factors Silt load Size distribution Particle shapes

Acoustic streaming and Sun's meridional circulation

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Research in Astronomy and Astrophysics 2016年第9期16卷 101-106页

作者： jose Manuel Valverde Faculty of Physics University of Seville

A vast number of physical processes involving oscillations of a bounded viscous fluid are relevantly influenced by acoustic streaming. When this happens a steady circulation of fluid develops in a thin boundary adjacent to the interface. Some examples are refracted sound waves, a fluid inside a spherical cavity undergoing torsional oscillations or a pulsating liquid droplet. Steady streaming around circular interfaces consists of a hemispherically symmetric recirculation of fluid from the equatorial plane to the polar axes closely resembling the meridional circulation pattern observed in the Sun＇s convection zone that determines the solar cycle. In this paper, it is argued that the acoustic pulsations exhibited by the Sun would lead to acoustic streaming in the boundary of the convection zone. A simple estimation using a typical dominant frequency of 3 mHz and the observed surface oscillation amplitude yields a steady streaming velocity Us - 10 m s^-1, which is on the order of the meridional circulation velocity observed in the Sun＇s convection zone.

关键词： Sun general -- Sun helioseismology -- Sun granulation -- Sun oscillations -- Sun fun-damental parameters -- Sun activity

Super d-antimagic Labelings of Disconnected Plane Graphs

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Acta Mathematica Sinica,English Series 2010年第12期26卷 2283-2294页

作者： Martin BAA Mirka MILLER Oudone PHANALASY Andrea SEMANIOV-feOVKOV Department of Applied Mathematics Technical University School of Electrical Engineering and Computer Science The University of Newcastle Department of Mathematics University of West Bohemia Department of Computer Science King's College London Department of Mathematics National University of Laos

This paper deals with the problem of labeling the vertices, edges and faces of a plane graph in such a way that the label of a face and the labels of the vertices and edges surrounding that face add up to a weight of that face, and the weights of all s-sided faces constitute an arithmetic progression of difference d, for each s that appears in the graph. The paper examines the existence of such labelings for disjoint union of plane graphs.

关键词： Plane graph d-antimagic labeling super d-antimagic labeling disjoint union of graphs

Magnetic field assisted fluidization:A modified Richardson-Zaki equation

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China Particuology 2007年第1期5卷 61-70页

作者： jose Manuel Valverde Antonio Castellanos Faculty of Physics Universidad de Sevilla Avenida Reina Mercedes s/n 41012 Sevilla Spain

Magnetic particles can be uniformly fluidized by coupling the gas flow with an externally imposed magnetic field. Interparticle forces generated by the magnetic field cause aggregation of the particles in chain-like structures preferentially oriented along the magnetic field lines. In the present paper, we study the implications of the formation of these special types of aggregates on the empirical Richardson-Zaki （RZ） equation, originally proposed to describe the expansion of fluidized beds of non-aggregated particles. We have addressed two important issues, namely the flow regime, which is a function of the size of the aggregates, and the effect of shape and orientation of the chain-like aggregates with respect to gas flow on fluid drag. We propose a modified RZ equation （MRZE） in which the velocity scale, given by the terminal settling velocity of the individual aggregates, and the RZ exponent are predetermined as a function of the chain length. The chain length depends on the ratio of the magnetic energy to gravitational energy, and is estimated from the magnetic field intensity, and particle magnetization, size and density. Predictions of the MRZE are successfully compared with published results in the literature on the expansion of magnetic particles in the presence of externally applied magnetic fields.

关键词： Fluidization Geldart B Magnetic particles Aggregation Richardson-Zaki equation

Extending dynamic models of mining subsidence

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中国有色金属学会会刊：英文版 2011年第S3期21卷 536-542页

作者： Andrew JAROSZ jose SAAVEDRA-ROSAS Western Australian School of Mines Curtin University

The movement and deformation processes of the overburden strata and ground surface, induced by underground mining, are affected by mining method, spatial relationships, geotechnical conditions of the rock strata and time. The authors reviewed and extended an existing classical prediction model of the dynamic subsidence, and proposed potential new research avenues offered by Cellular Automata (CA) models. The Knothe's influence function model and the significance of subcritical mining geometry were analyzed. The prediction results were verified against the subsidence field survey data to assess their quality and acceptability.

关键词： dynamic subsidence subsidence prediction cellular automata