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h.alth.m.nitoring of tim.-varying stoch.stic structures by latent com.onents and fuzzy expert system

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Earth.uake Engineering and Engineering Vibration 2008年第1期7卷 91-106页

作者： m. m. Ettefagh.m. h. sadeghi Vibration and m.dal Analysis Laboratory Department of Mechanical Engineering University of Tabriz Tabriz 51666 Iran

In th.s paper, a novel param.tric m.del-based decom.osition m.th.d is proposed for structural h.alth.m.nitoring of tim.-varying structures. For th.s purpose, th. advanced Functional-Series Tim.-dependent Auto Regressive m.ving Average （FS-TARm.） tech.ique is used to estim.te th. param.ters and innovation variance used in th. param.tric signal decom.osition sch.m.. Additionally, a unique feature extraction and reduction m.th.d based on th. decom.osed signals, known as Latent Com.onents （LCs）, is proposed. To evaluate th. efficiency of th. proposed m.th.d, num.rical sim.lation and an experim.ntal study in th. laboratory were conducted on a tim.-varying structure, wh.re various types of dam.ge were introduced. Th. Fuzzy Expert System.（FES） was used as a classification toot to dem.nstrate th.t th. proposed m.th.d successfully identifies different structural conditions wh.n com.ared with.oth.r m.th.ds based on non-reduced and ordinary feature extraction.

关键词： param.tric m.deling signal decom.osition feature extraction/reduction fuzzy classification

Th. Ph.ton Polarization Param.ter of 2h.n, γ）3h.reaction with.Inclusion of th. Electric Quadrupole Contribution

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Ch.nese Ph.sics Letters 2014年第9期31卷 32-35页

作者： h. sadeghi m. m.savi-Kh.nsari Departm.nt of Ph.sics Faculty of Science Arak University Arak 8349-8-38156 Iran

We use effective field th.ory （EFT） for th. calculation of neutron-deuteron radiative capture at very low energies. We present h.re th. use of EFT to calculate a low-energy ph.to-nuclear observable in th.ee-body system., th. ph.ton polarization param.ter and and fore-aft asym.etry at th.rm.l neutron energies up to next-to-next to leading order （N2 LO）, with.inclasion of th. electric quadrupole contribution. Th. ph.ton polarization param.ter in total is found to be Rc = -0.421±0.003 and is in good agreem.nt with.th. oth.r m.dern th.oretical calculations based on m.dern nucleon-nucleon potentials. In com.arison with.our previous work, a satisfactory agreem.nt with.th. available experim.ntal data is found by inclusion of th. electric quadrupole contribution.

关键词： Ph.TONS -- Polarization RESEARCh FIELD th.ory (Ph.sics) NEUTRON-deuteron interactions QUADRUPOLES Th.EE-body problem.(Ph.sics)

Th.ee-Body Calculation of 4h.（αα,γ）12C Reaction at Stellar Energies

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Ch.nese Ph.sics Letters 2015年第7期32卷 25-28页

作者： Firoozabadi m. m. sadeghi h. Departm.nt of Ph.sics University of Birjand Birjand Iran Departm.nt of Ph.sics Faculty of Science Arak University Arak 8349-8-38156 Iran

Th. triple-alph. reaction is th. key to our understanding about th. nucleosynth.sis and th. observed abundance of 12C in stars. On th. basis of our m.del, th. triple-alph. radiative capture process is studied by using th. th.ee-body Faddeev approach.as well as two- and th.ee-body electrom.gnetic currents. Th. bound and resonance states of 12 C are calculated via an inverse process： th.ee-a ph.todisintegration of a 12 C nucleus.

关键词： Th.ee-Body Calculation of C Reaction at Stellar Energies

Low-Energy Direct Capture in th. ^12C（α, γ）^16O Reaction

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Ch.nese Ph.sics Letters 2014年第6期31卷 67-71页

作者： h. sadeghi R. Gh.selni Departm.nt of Ph.sics Faculty of Science Arak University Arak 8349-8-38156 Iran

Th. spectra of ligh. nuclei provide th. first test of nuclear interaction m.dels. Th. reaction am.unt determ.nes th. relative abundance of m.st elem.nts in red giant stars, neutron stars, and black h.les. Due to th. fact th.t th.s reaction occurs at low energies, th. experim.ntal m.asurem.nt is very difficult and perh.ps im.ossible. In th.s work, th. radiative capture of th. ^12C（α, γ）^16O reaction at very low-energies is taken as a case study. Using th. m.Y potential we calculate th. astroph.sical Factor for transition E1 and E2. In com.arison with.oth.r th.oretical m.th.ds and available recent experim.ntal data, excellent agreem.nt is ach.eved for th. astroph.sical S-factor of th.s process.

关键词： INTERACTION m.del (Com.unication) COm.UNICATION -- Research ASTROPh.SICAL electric fields ASTROPh.SICAL m.gnetic fields Ph.SICAL & th.oretical ch.m.stry m.Th.m.TICAL analysis

Effective Dielectric Properties of Au-ZnS and Au-ZnO Plasm.nics Nanocom.osites in th. Terah.rtz Regim.

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Ch.nese Ph.sics Letters 2014年第10期31卷 96-99页

作者： A. Zolanvar h. sadeghi A. Ranjgar Departm.nt of Ph.sics Faculty of Science Arak University Arak 8349-8-38156 Iran

Com.osite m.terials based on plasm.nic nanoparticles allow building m.tam.terials with.very large effective perm.ttivity （positive or negative）. m.reover, if clustered or com.ined with.oth.r nanoparticles, it is also possible to generate effective m.gnetic perm.ability （positive or negative）, and an ad-h.c design would result in th. generation of double negative m.terials, and th.refore backward wave propagation. In th.s work, th. optical properties such.as th. effective perm.ttivity, perm.ability and refractive index of Au-ZnS and Au-ZnO nanocom.osites in a broad frequency range are studied. Th. enh.ncem.nt is attributed to energy transfer from.ZnS or ZnO to Au followed by a large local electrom.gnetic field on or near th. surface of th. Au nanoparticles. Local surface plasm.n resonance could be th. key＂ reason for th.s enh.ncem.nt. Th. surface plasm.n, in response to ch.nges in th. refractive index of th. local environm.nt, also depends on th. type of m.tal th.ough.th. bulk plasm. wavelength.and th. nano-particle com.ositions and geom.try.

关键词： DIELECTRIC properties NANOCOm.OSITE m.terials SUBm.LLIm.TER waves PERm.TTIVITY m.asurem.nt SURFACE plasm.n resonance ELECTROm.GNETIC fields

S-Factor of th. ^(3)h.α,γ)^(7)Li Reaction at Astroph.sical Energies

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Ch.nese Ph.sics Letters 2013年第10期30卷 59-62页

作者： h.sadeghi Departm.nt of Ph.sics Faculty of ScienceArak UniversityArak 8349-8-38156Iran

Th. astroph.sical S-factor forα-^(3)h.radiative capture is calculated at astroph.sical *** construct conserved two-and th.ee-body electrom.gnetic currents,using m.nim.l substitution in th. explicit m.m.ntum.dependence of th. two-and th.ee-nucleon *** realistic Argonne v_(18) two-nucleon and Urbana IX or Tucson–m.lbourne th.ee-nucleon interactions are considered for *** extrapolation of results for th. astroph.sical S-factor at zero energy,th. energy in th. order of 1 keV and less is found to be S(0)=0.107(0.112)keV·b,with.with.ut)th.ee-body interactions in satisfactory agreem.nt with.oth.r th.oretical results and experim.ntal data.

关键词： calculation substitution m.m.ntum

Structure of A=11 double-Λ h.pernuclei studied with.th.ee-body forces

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Ch.nese Ph.sics C 2013年第5期37卷 22-27页

作者： h. sadeghi Sh. Nah.dinejad K. Bah.am.nejad Departm.nt of Ph.sics Faculty of Science Arak University

Th. energy levels and AA bond energy of th. double-A h.pernucleus nBe are calculated considering two- and th.ee-nucleon forces. Th. interactions between th. constituent particles are contact interactions th.t reproduce th. low-energy binding energy of th. nuclei. Effective action is constructed to involve th. th.ee-body forces. In th.s paper, we com.are th. binding energy result th.t is obtained with.th. experim.ntal and oth.r m.dern nucleon- nucleon potentials. Th. results of all th. sch.m.s agree very well, sh.wing th. h.gh.accuracy of our present ability to calculate th. m.ny-nucleon bound state with.th.ee-body forces. Th. experim.ntal value of BAA（Be）=20.83 m.V seem. to be m.re com.atible with.our calculated value of BAA（Be）=-19.31 m.V in com.arison with.th. calculated result of 18.23 m.V by h.yam. et al.

关键词： five-body cluster A=11 double-A h.pernuclei binding energy th.ee-body forces

Ph.ton Linear Polarization Coefficient of th. Radiative Capture Process ^(2)h.p,γ)^(3)h. at Th.rm.l Energies

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Ch.nese Ph.sics Letters 2012年第12期29卷 52-56页

作者： h.sadeghi Departm.nt of Ph.sics Faculty of ScienceArak UniversityArak 8349-8-38156Iran

Th. ph.ton polarization param.ter of th. proton-deuteron radiative capture process at th.rm.l proton energies is calculated up to leading order(LO),using pionless effective field th.ory(EFT).In order to m.ke a com.arative study of th.s m.del,we com.are our results for th. ph.ton polarization param.ter with.th. realistic Argonne(AV14)and Argonne v18(AV18)m.dern nucleon-nucleon potentials and Urbana IX or Tucson-m.lbourne th.ee-nucleon *** th.oretical description of th. ^(2)h.p,γ)^(3)h. reaction at th.rm.l energies is com.licated by th. presence of th. Coulom. *** th. s-wave capture contribution to th. th.rm.l energy of th.s reaction is ***-body currents give sm.ll but significant contributions to som. of th. observables in th. proton-deuteron radiative capture cross section at th.rm.l neutron *** result is in good agreem.nt with.th. available experim.ntal data and potential m.dels'calculation at th.s order.

关键词： interaction. radiative Polarization

Plasm.nic Nanostructured Electrom.gnetic m.terials

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Ch.nese Ph.sics Letters 2012年第9期29卷 133-137页

作者： h.sadeghi h.Kh.lili m.Goodarzi Departm.nt of Ph.sics Faculty of ScienceArak UniversityArak 8349-8-38156Iran

We study th. m.terials th.t are com.osed of m.tals and *** plasm.nic and non-plasm.nic m.terials are ordered in geom.tric arrangem.nts with.dim.nsions th.t are fractions of th. wavelength.of ligh..A th.oretical m.del is developed to sim.late th. refractive index of th.se nano-structured electrom.gnetic m.terials wh.ch.support surface plasm.n *** contributing to th. refractive index sensitivity are explored *** with.size param.ters sm.ller by m.ch.less th.n 1 h.ve optical properties accurately predicted by th. quasi-electrostatic th.ory wh.le particles with.larger size param.ters necessitate *** sim.late a type of refractive index m.terial com.osed of m.tal and insulating dielectric nano-sph.res,wh.ch.are able to sustain th. propagation of infrared or visible frequency electrom.gnetic waves known as surface plasm.n polaritons.

关键词： refractive size arrangem.nt