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A com.arison of IBC with 1997 UBC for m.dal response spectrum.analysis in standard-occupancy buildings

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Earthquake Engineering and Engineering Vibration 2011年第1期10卷 99-113页

作者： Tariq m. Nahhas Um. Al-Qura University

This paper presents a com.arison of the seism.c forces generated from.a m.dal Response Spectrum.Analysis （m.SA） by applying the provisions of two building codes, the 1997 Uniform.Building Code （UBC） and the 2000-2009 International Building Code （IBC）, to the m.st com.on ordinary residential buildings of standard occupancy. Considering IBC as the state of the art benchm.rk code, the prim.ry concern is the safety of buildings designed using the UBC as com.ared to those designed using the IBC. A sam.le of four buildings with different layouts and heights was used for this com.arison. Each of these buildings was assum.d to be located at four different geographical sam.le locations arbitrarily selected to represent various earthquake zones on a seism.c m.p of the USA, and was subjected to code-com.liant response spectrum.analyses for all sam.le locations and for five different soil types at each location. Response spectrum.analysis was perform.d using the ETABS software package. For all the cases investigated, the UBC was found to be significantly m.re conservative than the IBC. The UBC design response spectra have higher spectral accelerations, and as a result, the response spectrum.analysis provided a m.ch higher base shear and m.m.nt in the structural m.m.ers as com.ared to the IBC. The conclusion is that ordinary office and residential buildings designed using UBC 1997 are considered to be overdesigned, and therefore they are quite safe even according to the IBC provisions.

关键词： response spectrum.analysis seism.c forces m.lti-story buildings seism.c design building codes IBC UBC

SIGNATURES OF UNIVERSAL CHARACTERISTICS OF FRACTAL FLUCTUATIONS IN GLOBAL m.AN m.NTHLY TEm.ERATURE ANOm.LIES

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Journal of System. Science & Com.lexity 2011年第1期24卷 14-38页

作者： A. m. SELVAm Indian Institute of Tropical m.teorology Pune 411008 India

This paper proposes a general system. theory for fractals visualising the em.rgence of successively larger scale fluctuations resulting from.the space-tim. integration of enclosed sm.ller scale fluctuations. Global gridded tim. series data sets of m.nthly m.an tem.eratures for the period 1880- 2007/2008 are analysed to show that data sets and corresponding power spectra exhibit distributions close to the m.del predicted inverse power law distribution. The m.del predicted and observed universal spectrum.for interannual variability rules out linear secular trends in global m.nthly m.an tem.eratures. Global warm.ng results in intensification of fluctuations of all scales and m.nifested im.ediately in high frequency fluctuations.

关键词： Fractals and statistical norm.l distribution golden m.an and fractal fluctuations long- range correlations and fat tail distributions power law distributions.

Glia-to-neuron reprogram.ing to the rescue?

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Neural Regeneration Research 2025年第5期20卷 1395-1396页

作者： Jack W.Hickm.tt Cindi m.m.rshead departm.nt of Surgery University of TorontoTorontoONCanada Donnelly Centre for Cellular and Biom.lecular Research TorontoONCanada Institute of Biom.dical Engineering University of TorontoTorontoONCanada The KITE Research Institute Toronto Rehabilitation InstituteUniversity Health NetworkTorontoONCanada

Over the last two decades,the dogm. that cell fate is im.utable has been increasingly challenged,with im.ortant im.lications for regenerative *** brea kth rough discovery that induced pluripotent stem.cells could be generated from.adult m.use fibroblasts is powerful proof that cell fate can be *** exciting extension of the discovery of cell fate im.erm.nence is the direct cellular reprogram.m.ng hypothesis-that term.nally differentiated cells can be reprogram.ed into other adult cell fates without first passing through a stem.cell state.

关键词： program.ing passing proof

Identification of Iron Oxides Qualitatively/Quantitatively Form.d during the High Tem.erature Oxidation of Superalloys in Air and Steam.Environm.nts

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Journal of m.terials Science & Technology 2009年第4期25卷 479-482页

作者： m. Siddique N. Hussain m. Shafi Physics Division PINSTECH m.terials Division PINSTECH

m.ssbauer spectroscopy has been used to study the m.rphology of iron oxides form.d during the oxidation of superalloys, such as SS-304L （1.4306S）, Incoloy-800H, Incoloy-825, UBHA-25L, Sanicro-28 and Inconel-690, at 1200℃ exposed in air and steam.environm.nts for 400 h. The basic aim.was to identify and com.are the iron oxides qualitatively and quantitatively, form.d during the oxidation of these alloys in two environm.nts. The behaviour of alloy UBHA-25L in high tem.erature oxidation in both environm.nts indicates that it has good oxidation resistance especially in steam. whereas Sanicro-28 has excellent corrosion resistance in steam.environm.nt. In air oxidation of Inconel-690 no iron oxide, with established m.ssbauer param.ters, was detected.

关键词： Superalloys m.ssbauer spectroscopy Oxidation Corrosion products

Upshot of ohm.cally dissipated Darcy-Forchheim.r slip flow of m.gnetohydrodynam.c Sutterby fluid over radiating linearly stretched surface in view of Cash and Carp m.thod

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Applied m.them.tics and m.chanics(English Edition) 2019年第6期40卷 861-876页

作者： S. BILAL m. SOHAIL R. NAZ m. Y. m.LIK m. ALGHAm.I departm.nt of m.them.tics Air UniversityIslamabad 44000Pakistan departm.nt of Applied m.them.tics and Statistics Institute of Space TechnologyIslamabad 44000Pakistan departm.nt of m.them.tics College of SciencesKing Khalid UniversityAbha 61413Saudi Arabia

The present work concerns the m.m.ntum.and heat transm.ssion of the electro-m.gnetohydrodynam.c (E-m.D) boundary layer Darcy-Forchheim.r flow of a Sutterby fluid over a linear stretching sheet with slip. The nonlinear equations for the proposed m.del are analyzed num.rically. Suitable techniques are used to transform.the coupled nonlinear partial differential equations (Pdes) conform.ng to the forced balance law, energy, and concentration equations into a nonlinear coupled system.of ordinary differential equations (Odes). Num.rical solutions of the transform.d nonlinear system.are obtained using a shooting m.thod, im.roved by the Cash and Carp coefficients. The influence of im.ortant physical variables on the velocity, the tem.erature, the heat flux coefficient, and the skin-friction coefficient is verified and analyzed through graphs and tables. From.the com.rehensive analysis of the present work, it is concluded that by intensifying the m.gnitude of the Hartm.nn num.er, the m.m.ntum.distribution decays, whereas the therm.l profile of fluid increases. Furtherm.re, it is also shown that by aug- m.nting the values of the m.m.ntum.slip param.ter, the velocity profile dim.nishes. It is found that the Sutterby fluid m.del shows shear thickening and shear thinning behaviors. The m.m.ntum.profile shows that the m.gnitude of velocity for the shear thickening case is dom.nant as com.ared with the shear thinning case. It is also dem.nstrated that the Sutterby fluid m.del reduces to a Newtonian m.del by fixing the fluid param.ter to zero. In view of the lim.ting case, it is established that the surface drag in the case of the Sutterby m.del shows a trifling pattern as com.ared with the classical case.

关键词： Sutterby fluid therm.l and m.m.ntum slip shooting m.thod ohm.c dissipation Darcy-Forchheim.r law Cash and Carp m.thod

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. Jahanabadi m. m.ilah m. Z. m. Zain H. m. Hooi departm.nt of System.Dynam.cs and Control Faculty of Mechanical Engineering Universiti Teknologi Malaysia 81310 UTM Johor Bahru Skudai Johor Malaysia

In this paper, the 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. The study em.hasizes on the application and control of PAm.actuators which m.y be considered as the new generation of actuators com.rising fluidic m.scle that has high-tension force, high power to weight ratio and high strength in spite of its drawbacks in the form.of high nonlinearity behaviour, high hysteresis and tim. varying param.ters. Fuzzy Logic （FL） is used as a technique to estim.te the best value of the inertia m.trix of robot arm.essential for the AFC m.chanism.that is com.lem.nted with a conventional Propor- tional-Integral-derivative （PID） control at the outerm.st loop. A sim.lation study was first perform.d followed by an experi- m.ntal investigation for validation. The experim.ntal study was based on the independent joint tracking control and coordinated m.tion control of the arm.in Cartesian or task space. In the form.r, the PAm.actuated arm.is com.anded to track the prescribed trajectories due to harm.nic excitations at the joints for a given frequency, whereas for the latter, two sets of trajectories with different loadings were considered. A practical rig utilizing a Hardware-In-The-Loop Sim.lation （HILS） configuration was developed and a num.er of experim.nts were carried out. The results of the experim.nt and the sim.lation works were in good agreem.nt, which verified the effectiveness and robustness of the proposed AFCAFL schem. actuated by PAm.

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

Reactive Extraction of Alcohols from.Apolar Hydrocarbons with Aqueous Solutions

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Tsinghua Science and Technology 2006年第2期11卷 222-227页

作者： Boris Kuzm.novi Norbert J. m. Kuipers André B. de Haan Gerard Kwant Akzo Nobel Chem.cals Research Arnhem The Netherlands University of Twente Enschede The Netherlands DSm.Research Geleen The Netherlands

The aqueous solutions are evaluated as sustainable reactive extraction solvents for the recovery of m.nohydroxyl alcohols （benzyl alcohol, 1-hexanol, cyclohexanol） present in few-percent concentrations in apolar hydrocarbons （toluene, n-hexane, and cyclohexane） by considering two approaches. An aqueous solution containing a reactive extractant, like borate salts, borate com.lexes, a m.nosalt of dicarboxylic acid, hydroxypropyl-cyclodextrins, and silver nitrate, shows lim.ted potential to be used. Another approach, in which the alcohol is chem.cally m.dified prior to the extraction into an easy-extractable form. in this case a m.noester/carboxylic acid, shows m.ch m.re potential. An environm.ntally benign aqueous solution of sodium.hydrogen carbonate can provide a distribution ratio of benzyl alcohol up to 200, leaving the solubility of the organic solvent in the aqueous solution unchanged relative to pure water and therefore increasing the selectivity with two orders of m.gnitude. The m.dification of arom.tic, cyclo-aliphatic, and linear aliphatic alcohols can be perform.d efficiently in the apolar organic solvent without need for a catalyst. The recovery of the m.dified alcohol can be perform.d by back-extraction in com.ination with a spontaneous hydrolysis.

关键词： reactive extraction alcohol polar hydrocarbons

Im.act of tropospheric m.delling on GNSS vertical precision:an em.irical analysis based on a local active network

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International Journal of Digital Earth 2018年第9期11卷 880-896页

作者： m.Selm.ra Garrido m.Clara de Lacy Ana m.Rojas departm.nt of Cartographic Geodetic and Photogrammetric EngineeringUniversity of JaénJaenSpain Center for Advanced Studies in Earth Sciences University of JaénJaenSpain Research group RNm.82–m.crogeodesia Jaén University of JaénJaenSpain

The troposphere affects Global Navigation Satellite System.GNSS)signals due to the variability of the refractive *** delay is a function of the satellite elevation angle and the altitude of the GNSS receiver and depends on the atm.spheric *** the residual tropospheric delay is not m.delled carefully a bias error will occur in the vertical *** order to analyse the precise altim.tric positioning based on a local active network,four scenarios in Southern Spain with different topographical,environm.ntal,and m.teorological conditions are presented,considering both favourable and non-favourable *** use of surface m.teorological observations allows us to take into account the tropospheric conditions instead of a standard atm.sphere,but introduces a residual tropospheric bias which reduces the accuracy of precise GNSS ***,with short observation tim.s it is recom.ended not to estim.te troposphere param.ters,but to use an a priori m.del together with the standard *** results confirm.that it is possible to achieve centim.tre-scale vertical accuracy and precision with real tim. kinem.tic positioning even with large elevation differences with respect to the nearest reference *** num.rical results m.y be taken into consideration for im.roving the altim.tric configuration of the local active network.

关键词： Altim.try GNSS m.teorological data active network tropospheric refraction

Relativistic particle scattering states with tensor potential and spatially-dependent m.ss

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Chinese Physics C 2013年第5期37卷 14-21页

作者： m. Eshghi m. R. Abdi departm.nt of Physics Faculty of Science Imam Hossein Comprehensive University departm.nt of Physics Faculty of Science University of Isfahan

We investigate the relativistic equation for particles with spin 1/2 in the q-param.ter m.dified P5schl- Teller potential, including Coulom.-like tensor interaction with spatially-dependent m.ss for the D-dim.nsion. We present approxim.te solutions of the Dirac equation with these potentials for any spin-orbit quantum.num.er k under spin sym.etry. The norm.lized wave functions are expressed in term. of the hyper-geom.tric series of the scattering states on the k/2π scale. We also give the form.la for the phase shifts, and use the Nikiforov-Uvarov m.thod to obtain the energy eigen-values equation.

关键词： Dirac equation relativistic scattering states m.dified PSschl-Teller potential spin sym.etry tensor interaction