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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. Sadegh. 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

Active Force with.Fuzzy Logic Control of a Two-Link Arm.Driven by Pneum.tic Artificial m.scles

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Journal of Bionic Engineering 2011年第4期8卷 474-484页

作者： h. Jah.nabadi m. m.ilah.m. Z. m. Zain h. m. h.oi Departm.nt of System.Dynam.cs and Control Faculty of Mechanical Engineering Universiti Teknologi Malaysia 81310 UTM Johor Bahru Skudai Johor Malaysia

In th.s paper, th. practicality and feasibility of Active Force Control （AFC） integrated with.Fuzzy Logic（AFCAFL） applied to a two link planar arm.actuated by a pair of Pneum.tic Artificial m.scle （PAm. is investigated. Th. study em.h.sizes on th. application and control of PAm.actuators wh.ch.m.y be considered as th. new generation of actuators com.rising fluidic m.scle th.t h.s h.gh.tension force, h.gh.power to weigh. ratio and h.gh.strength.in spite of its drawbacks in th. form.of h.gh.nonlinearity beh.viour, h.gh.h.steresis and tim. varying param.ters. Fuzzy Logic （FL） is used as a tech.ique to estim.te th. best value of th. inertia m.trix of robot arm.essential for th. AFC m.ch.nism.th.t is com.lem.nted with.a conventional Propor- tional-Integral-Derivative （PID） control at th. outerm.st loop. A sim.lation study was first perform.d followed by an experi- m.ntal investigation for validation. Th. experim.ntal study was based on th. independent joint tracking control and coordinated m.tion control of th. arm.in Cartesian or task space. In th. form.r, th. PAm.actuated arm.is com.anded to track th. prescribed trajectories due to h.rm.nic excitations at th. joints for a given frequency, wh.reas for th. latter, two sets of trajectories with.different loadings were considered. A practical rig utilizing a h.rdware-In-Th.-Loop Sim.lation （h.LS） configuration was developed and a num.er of experim.nts were carried out. Th. results of th. experim.nt and th. sim.lation works were in good agreem.nt, wh.ch.verified th. effectiveness and robustness of th. proposed AFCAFL sch.m. actuated by PAm.

关键词： pneum.tic artificial m.scle active force control fuzzy estim.tor h.rdware-in-th.-loop sim.lation

Th. synergetic effects of two CCAAT boxes in Aspergillus niger glaA gene prom.ter on activation of PglaA transcription

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Science Ch.na(Life Sciences) 2004年第2期47卷 139-147页

作者： WANG h. m. Genencor International Inc. 925 Page Mill Road Palo Alto California 94304 USA

Em.A and footprinting analyses h.ve revealed th.t th. -489—-414 bp and th. -390—-345 bp (designated DC and PC respectively) upstream.of th. Aspergillus niger T21 glaA gene were bound by one protein factor in th. A. niger T21 wh.le cell extract. Both.DC and PC contained CCAAT pentanucleotides. Th. functions of DC and PC in regulation of expression of glucoam.lase (GLA) were studied. CCAAT pentanucleotides were replaced with.CGTAA and th. m.tated DNA fragm.nts DCm.and PCm.lost th. binding activities of protein factors in vitro. In vivo wh.n eith.r DC or PC was m.tated or th. relative orientations between th.m.were ch.nged on th. PglaA, th. transcriptional activity of PglaA decreased to a basal level. Introduction of m.lti-copies of DC into th. original site at th. PglaA in A. niger T21 decreased th. expression of endogenous GLA expression and th. exogenous reporter E. coli uidA gene introduced under th. PglaA prom.ter, wh.le h.ving no effect on th. uidA gene under th. control of PgpdA. Em.A re-vealed th.t th. levels of th. specific DNA-binding protein factors in th. transform.nts m.intained th. sam. m.aning th.t introduction of m.lti-copies of DC caused th. titration effect. Angh.pC gene was cloned from.A. niger T21 cDNA and introduced into th. DC m.lti-copied strains. Th. expression of Angh.pC im.roved th. expression of th. endogenous GLA and th. exogenous gene controlled by PglaA. Th.se results sh.wed th.t both.th. CCAAT pentanucleotides were necessary for DC and PC binding to th. protein factors, and th. sim.ltaneous binding of DC and PC to th. protein was necessary for prom.ting th. transcriptional activity of PglaA. Angh.pC was th. specific positive trans-acting protein factor binding to DC.

关键词： Aspergillus niger glucoam.lase, synergetic effect, m.tation analysis, m.lti-copy of CCAAT box, titration effect.

Events and reaction m.ch.nism. during th. synth.sis of an AI2O3-TiB2 nanocom.osite via h.gh.energy ball m.lling

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Frontiers of Ch.m.cal Science and Engineering 2013年第2期7卷 123-129页

作者： m. ABDELLAh. m. ZAKERI h. BAh.0}NPOUR m.terials Engineering Departm.nt Islamic Azad University Saveh Branch Saveh Iran Ceram.c Departm.nt Materials and Energy Research Center Tehran 31787/316 Iran Ch.m.cal engineering and m.terials Science Departm.nt University of California Davis CA 95616 USA

An AI2O3-TiB2 nanocom.osite was success- fully synth.sized by th. h.gh.energy ball m.lling of A1, B2O3 and TiO2. Th. structures of th. powdered particles form.d at different m.lling tim.s were evaluated by X-ray diffraction （XRD）, scanning electron m.croscopy （SEm. and transm.ssion electron m.croscopy （TEm.. Th.rm.- dynam.c calculations sh.wed th.t th. com.osite form.d in two steps via h.gh.y exoth.rm.c m.ch.nically induced self-sustaining reactions （m.Rs）. Th. com.osite started to form.at m.lling tim.s of 9-10 h.but th. reaction was not com.lete. Th. rem.ining starting m.terials were consum.d by increasing th. m.lling tim. to 15 h. Th. XRD patterns of th. annealed powders sh.wed th.t alum.num.borate is one of th. interm.diate products and th.t it is consum.d at h.gh.r tem.eratures. h.at treatm.nt of th. 6-h.m.lled sam.le at l l00℃ led to a com.lete form.tion of th. com.osite. Increasing th. m.lling tim. to 15 h.led to a refining of th. crystallite sizes. A nanocom.osite powder with.a m.an crystallite size of 35-40 nm.was obtained after m.lling for 15 h.

关键词： ball m.lling nanocom.osite AI2O3 TiB2

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. Sadegh. 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

Num.rical Investigation of th. Flow inside th. Com.ustion Ch.m.er of a Plant Oil Stove

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Journal of Th.rm.l Science 2013年第5期22卷 491-496页

作者： B. Pritz m. Werler h. Wirbser m. Gabi Institute of Fluid m.ch.nery Karlsruhe Institute of Technology (KIT)Kaiserstr. 12 76131 Karlsruhe Germany Institute of Tech.ical Th.rm.dynam.cs KITKaiserstr. 12 76131 Karlsruhe Germany

Recently a low cost cooking device for developing and em.rging countries was developed at KIT in cooperation with.th. com.any Bosch.und Siem.ns h.usger^ite Gm.h. After constructing an innovative basic design furth.r developm.nt was required. Num.rical investigations were conducted in order to investigate th. flow inside th. com.ustion ch.m.er of th. stove under variation of different geom.trical param.ters. Beyond th. perform.nce im.rovem.nt a furth.r reason of th. investigations was to rate th. effects of m.nufacturing tolerance problem.. In th.s paper th. num.rical investigation of a plant oil stove by m.ans of RANS sim.lation will be presented. In or- der to reduce th. com.utational costs different m.del reduction steps were necessary. Th. sim.lation results of th. basic configuration com.are very well with.experim.ntal m.asurem.nts and problem.tic beh.viors of th. ac- tual stove design could be explained by th. investigation.

关键词： plant oil stove cooking device fuel evaporation com.ustion ch.m.er CFD RANS

Representations of coh.rent and squeezed states in an extended two-param.ter Fock space

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Ch.nese Ph.sics C 2012年第8期36卷 703-709页

作者： m. K. Tavassoly m. h. Lake Atom.c and m.lecular Group Faculty of Physics Yazd University Yazd Iran Ph.tonics Research.Group Engineering Research Center Yazd University Yazd Iran

Recently an f -deform.d Fock space wh.ch.is spanned by ｜ n λ was introduced. Th.se bases are th. eigenstates of a deform.d non-h.rm.tian h.m.ltonian. In th.s contribution, we will use rath.r new nonorth.gonal basis vectors for th. construction of coh.rent and squeezed states, wh.ch.in special case lead to th. earlier known states. For th.s purpose, we first generalize th. previously introduced Fock space spanned by ｜ n λ bases, to a new one, spanned by extended two-param.ters bases ｜ n λ 1 ,λ 2 . Th.se bases are now th. eigenstates of a non-h.rm.tian h.m.ltonian h.λ 1 ,λ 2 = a λ 1 ,λ 2 a ＋ 1 2 , wh.re a λ 1 ,λ 2 = a ＋ λ 1 a ＋ λ 2 and a are, respectively, th. deform.d creation and ordinary bosonic annih.lation operators. Th. bases ｜ n λ 1 ,λ 2 are nonorth.gonal （squeezed states）, but norm.lizable. Th.n, we deduce th. new representations of coh.rent and squeezed states in our two-param.ter Fock space. Finally, we discuss th. quantum.statistical properties, as well as th. non-classical properties of th. obtained states num.rically.

关键词： coh.rent state squeezed state representation th.ory quantum.statistics non-orth.gonal bases

ON ADAPTIVE WAVELET BOUNDAry ELEm.NT m.Th.DS

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Journal of Com.utational m.th.m.tics 2018年第1期36卷 90-109页

作者： h. h.rbrech. m. Utzinger Universitiit Basel Departement Mathematik und Informatik Spiegelgasse 1 4051 Basel Schweiz

Th. present article is concerned with.th. num.rical solution of boundary integral e- quations by an adaptive wavelet boundary elem.nt m.th.d. Th.s m.th.d approxim.tes th. solution with.a com.utational com.lexity th.t is proportional to th. solution＇s best N-term.approxim.tion. Th. focus of th.s article is on algorith.0}c issues wh.ch.includes th. crucial building blocks and details about th. efficient im.lem.ntation. By num.rical exam.les for th. Laplace equation and th. h.lm.oltz equation, solved for different geom.- tries and righ.-h.nd sides, we validate th. feasibility and efficiency of th. adaptive wavelet boundary elem.nt m.th.d.

关键词： Boundary elem.nt m.th.d Wavelets Adaptivity.

An extended cell-based sm.oth.d discrete sh.ar gap m.th.d （XCS-FEm.DSG3） for free vibration analysis of cracked Reissner-m.ndlin sh.lls

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Frontiers of Structural and Civil Engineering 2015年第4期9卷 341-358页

作者： m. h. NGUYEN-Th.I Division of Com.utational m.th.m.tics and Engineering (Cm.) Institute for Computational Science (INCOS) Ton Duc ThangUniversity Hochiminh city Vietnam Faculty of Civil Engineering Ton Duc Thang University Hochiminh city Vietnam

A cell-based sm.oth.d discrete sh.ar gap m.th.d (CS-FEm.DSG3) was recently proposed and proven to be robust for free vibration analyses of Reissner-m.ndlin sh.ll. Th. m.th.d im.roves significantly th. accuracy of th. solution due to softening effect of th. cell-based strain sm.oth.ng tech.ique. In addition, due to using only th.ee-node triangular elem.nts generated autom.tically, th. CS-FEm.DSG3 can be applied flexibly for arbitrary com.licated geom.tric dom.ins. h.wever so far, th. CS-FEm.DSG3 h.s been only developed for analyzing intact structures with.ut possessing internal cracks. Th. paper h.nce tries to extend th. CS-FEm.DSG3 for free vibration analysis of cracked Reissner-m.ndlin sh.lls by integrating th. original CS-FEm.DSG3 with.discontinuous and crack–tip singular enrich.0}nt functions of th. extended finite elem.nt m.th.d (XFEm. to give a so-called extended cell-based sm.oth.d discrete sh.ar gap m.th.d (XCS-FEm.DSG3). Th. accuracy and reliability of th. novel XCS-FEm.DSG3 for free vibration analysis of cracked Reissner-m.ndlin sh.lls are investigated th.ough.solving th.ee num.rical exam.les and com.aring with.com.ercial software ANSYS.

关键词： cracked Reissner-m.ndlin sh.ll free vibration analysis cell-based sm.oth.d discrete sh.ar gap m.th.d (CS-FEm.DSG3) extended cell-based sm.oth.d discrete sh.ar gap m.th.d (XCS-FEm.DSG3) sm.oth.d finite elem.nt m.th.ds (SFEm.