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Angular Dependence of Lateral and Levitation Forces in Asym.etric Sm.ll m.gnet/Superconducting System.

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Ch.nese Ph.sics Letters 2007年第9期24卷 2700-2703页

作者： h. m. al-khateeb m. K. alqadi F. Y. alzoubi N. Y. Ayoub Departm.nt of Ph.sics Jordan University of Science and Technology Irbid Jordan Sch.ol of Applied Natural Sciences German Jordanian University Amman Jordan

Th. dipole-dipole interaction m.del is used to calculate th. angular dependence of lateral and levitation forces on a sm.ll perm.nent m.gnet and a cylindrical superconductor in th. m.issner state lying laterally off th. sym.etric axis of th. cylinder. Under th. assum.tion th.t th. lateral displacem.nt of th. m.gnet is sm.ll com.ared with.th. ph.sical dim.nsions of th. system. we obtain analytical expressions for th. lateral and levitation forces as functions of geom.trical param.ters of th. superconductor as well as th. h.igh., th. lateral displacem.nt and th. orientation of m.gnetic m.m.nt of th. m.gnet. Th. effect of th.ckness and radius of th. superconductor on th. levitation force is sim.lar to th.t for a sym.etric m.gnet/superconducting cylinder system. but with.n th. range of lateral displacem.nt. Th. splitting in th. levitation force increases with.th. increasing angle of orientation of th. m.gnetic m.m.nt of th. m.gnet. For a given lateral displacem.nt of th. m.gnet, th. lateral force vanish.s wh.n th. m.gnetic m.m.nt is perpendicular to th. surface of th. superconductor and h.s a m.xim.m.value wh.n th. m.m.nt is parallel to th. surface. For a given orientation of th. m.gnetic m.m.nt, th. lateral force h.s a linear relationsh.p with.th. lateral displacem.nt. Th. stability of th. m.gnet above th. superconducting cylinder is discussed in detail.

关键词： Th.N SUPERCONDUCTING DISKS m.ISSNER STATE m.GNETIC-LEVITATION PERm.NENT-m.GNET CERAm.CS CYLINDER SAm.LE

Vibrations in m.gnet/Superconductor Levitation System.

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Ch.nese Ph.sics Letters 2006年第6期23卷 1641-1644页

作者： F. Y. alzoubi h. m. al-khateeb m. K. alqadi N. Y. Ayoub Departm.nt of Ph.sics Jordan University of Science and Technology Irbid Jordan Departm.nt of Ph.sics Yarmouk University Irbid Jordan Sch.ol of Applied Natural Sciences German Jordanian University Amman Jordan

Th. problem.of a sm.ll m.gnet levitating above a very th.n superconducting disc in th. m.issner state is analysed. Th. dipole-dipole interaction m.del is em.loyed to derive analytical expressions for th. interaction energy, levitation force, m.gnetic stiffness and frequency of sm.ll vibrations about th. equilibrium.position in two different configurations, i.e. with.th. m.gnetic m.m.nt parallel and perpendicular to th. superconductor. Th. results sh.w th.t th. frequency of sm.ll vibrations decreases with.th. increasing levitation h.igh. for a particular radius of th. superconducting disc, wh.ch.is in good agreem.nt with.th. experim.ntal results. h.wever, th. frequency increases m.notonically up to saturation by increasing th. radius of th. disc for a particular h.igh. of th. m.gnet. In addition, th. frequency of vibrations is h.gh.r wh.n th. system.is in th. vertical configuration th.n th.t wh.n th. system.is in th. h.rizontal configuration.

关键词： m.ISSNER STATE Sm.LL m.GNET FORCE STIFFNESS SUPERCONDUCTORS SIZE

Levitation and lateral forces between a point m.gnetic dipole and a superconducting sph.re

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Ch.nese Ph.sics B 2016年第5期25卷 453-456页

作者： h.m.al-khateeb m.K alqadi F Y alzoubi B albiss m.K h.san (Qaseer) N Y Ayoub Departm.nt of Ph.sics Jordan University of Science and Technology Sch.ol of Basic Sciences and h.m.nities German Jordanian University

Th. dipole–dipole interaction m.del is em.loyed to investigate th. angular dependence of th. levitation and lateral forces acting on a sm.ll m.gnet in an anti-sym.etric m.gnet/superconducting sph.re system. Breaking th. sym.etry of th. system.enables us to study th. lateral force wh.ch.is im.ortant in th. stability of th. m.gnet above a superconducting sph.re in th. m.issner state. Under th. assum.tion th.t th. lateral displacem.nt of th. m.gnet is sm.ll com.ared to th. ph.sical dim.nsions of our proposed system. analytical expressions are obtained for th. levitation and lateral forces as a function of th. geom.trical param.ters of th. superconductor as well as th. h.igh., th. lateral displacem.nt, and th. orientation of th. m.gnetic m.m.nt of th. m.gnet. Th. dependence of th. levitation force on th. h.igh. of th. levitating m.gnet is sim.lar to th.t in th. sym.etric m.gnet/superconducting sph.re system.with.n th. range of proposed lateral displacem.nts. It is found th.t th. levitation force is linearly dependent on th. lateral displacem.nt wh.reas th. lateral force is independent of th.s displacem.nt. A sinusoidal variation of both.forces as a function of th. polar and azim.th.l angles specifying th. orientation of th. m.gnetic m.m.nt is observed. Th. relationsh.p between th. stability and th. orientation of th. m.gnetic m.m.nt is discussed for different orientations.

关键词： lateral and levitation forces m.issner effect dipole–dipole interaction m.del superconductor

Local Sim.larity Relationsh.ps of Non-Dim.nsional Wind and Tem.erature Gradient in th. Tower-Layer Atm.sph.re over Beijing City

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Advances in Atm.sph.ric Sciences 2000年第4期17卷 636-648页

作者：徐玉貌钱永甫 al-Jiboori m. h. Departm.nt of Atm.sph.ric Science Nanjing University Nanjing Nanjing University Japan

m.crom.teorological data for wind and tem.erature from.a 325 m.h.gh.tower in Beijing City are analyzed by use of local sim.larity th.ory. Non-dim.nsional wind and tem.erature gradients, Ph.(m. and Ph.(h., are determ.ned by th.ee tech.iques called, respectively, eddy-correlation, m.an profiles and inertia-subrange cospectra (ISC) m.th.d for a wide range of atm.sph.ric stratification from.unstable to stable conditions. Average dissipation rate Ph.(e) of turbulent kinetic energy (TKE) is evaluated from.u-spectrum. as a quantity required in th. last tech.ique. Ratio of th. eddy transfer coefficients, alph.(= K-h./ K-m., is calculated from.Ph.(m. and Ph.(h. estim.tions. Th. results from.various tech.iques are com.ared with.each.oth.r and with.som. available em.irical results in th. tower-layer, It is sh.wn th.t th. em.irical relationsh.ps determ.ned by m.an profiles and ISC m.th.ds in th. lower-layer turbulence ore in agreem.nt with.each.oth.r and with.som. oth.r results.

关键词： local sim.larity non-dim.nsional gradients of wind and tem.erature dissipation rate ratio of eddy diffusivities spectra and cospectra

m.lecular aspects of m.RS-CoV

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Frontiers of m.dicine 2017年第3期11卷 365-377页

作者： ali A. Rabaan ali m. Bazzi Sh.m.ah.h. al-Ah.ed Jaffar A. al-Tawfiq m.lecular Diagnostic Laboratory Johns Hopkins Aramco HeaIthcare Dhahran 31311 Saudi Arabia m.crobiology Laboratory JohnsHopkins Aramco Healthcare Dhahran 3131i Saudi Arabia Specialty Paediatric m.dicine Qatif CentralHospitaL Qatif 32654 Saudi Arabia Specialty Internal m.dicine Johns Hopkins Aramco Healthcare Dhahran 31311 Saudi Arabia Indiana University Sch.ol of m.dicine Indianapolis IN 46202 USA

m.ddle East respiratory syndrom. coronavirus （m.RS-CoV） is a betacoronavirus wh.ch.can cause acute respiratory distress in h.m.ns and is associated with.a relatively h.gh.m.rtality rate. Since it was first identified in a patient wh. died in a Jeddah.h.spital in 2012, th. World h.alth.Organization h.s been notified of 1735 laboratory-confirm.d cases from.27 countries, including 628 death.. m.st cases h.ve occurred in Saudi Arabia. m.RS-CoV ancestors m.y be found in Old World bats of th. Vespertilionidae fam.ly. After a proposed bat to cam.l switch.ng event, transm.ssion of m.RS-CoV to h.m.ns is likely to h.ve been th. result of m.ltiple zoonotic transfers from.drom.dary cam.ls. h.m.n-to-h.m.n transm.ssion appears to require close contact with.infected persons, with.outbreaks m.inly occurring in h.spital environm.nts. Outbreaks h.ve been associated with.inadequate infection prevention and control im.lem.ntation, resulting in recom.endations on basic and m.re advanced infection prevention and control m.asures by th. World h.alth.Organization, and issuing of governm.nt guidelines based on th.se recom.endations in affected countries including Saudi Arabia. Evolutionary ch.nges in th. virus, particularly in th. viral spike protein wh.ch.m.diates virus-h.st cell contact m.y potentially increase transm.ssion of th.s virus. Efforts are on-going to identify specific evidence-based th.rapies or vaccines. Th. broad-spectrum.antiviral nitazoxanide h.s been sh.wn to h.ve in vitro activity against m.RS-CoV. Synth.tic peptides and candidate vaccines based on regions of th. spike protein h.ve sh.wn prom.se in rodent and non-h.m.n prim.te m.dels. GLS-5300, a proph.lactic DNA-plasm.d vaccine encoding S protein, is th. first m.RS-CoV vaccine to be tested in h.m.ns, wh.le m.noclonal antibody, m.36 h.s given prom.sing results in anim.l m.dels and h.s potential for use in outbreak situations.

关键词： m.RS-CoV Saudi Arabia spike protein transm.ssion evolution vaccine

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.

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.ic 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.0}ltz 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.