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Two New Control Signal Approaches for Obtaining the m.AS-CDm.and a Real-tim. Application

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international Journal of Autom.tion and com.uting 2011年第2期8卷 254-261页

作者： m.r cal Atilla Bir Bernd Tibken Departm.nt of Electrical Engineering Istanbul Technical University Departm.nt of Electronic Engineering University of Wuppertal

The coefficient diagram.m.thod （CDm. is one of the m.st effective control design m.thods. it creates control system. that are very stable and robust with responses without the overshoot and sm.ll settling tim.. Furtherm.re, all control param.ters of the control system. are changed by varying som. adjustm.nt param.ters in CDm.depending on the dem.nds. The m.del reference adaptive system. （m.AS） are the system. that follow and change the control param.ters according to a given m.del reference system. There are several m.thods to com.ine the CDm.with m.AS. One of these is to use the m.AS param.ters as a gain of the CDm.param.ters. Another is to directly use the CDm.param.ters as the m.AS param.ters. in the industrial applications, the system.param.ters can be changed frequently, but if the controller, by self-tuning, recalculates and develops its own param.ters continuously, the system.becom.s m.re robust. Also, if the poles of the controlled system. approach the jw axis, the response of the closed-loop m.AS becom.s m.re and m.re insufficient. in order to obtain better results, CDm.is com.ined with a self-tuning m.del reference adaptive system. System. controlled by a m.del reference adaptive controller give responses with sm.ll or without overshoot, have sm.ll settling tim.s, and are m.re robust. Thus, in this paper, a hybrid com.ination of m.AS and CDm.is developed and two different control structures of the control signal are investigated. The two m.thods are com.ared with m.AS and applied to real-tim. process control system..

关键词： Coefficient diagram.m.thod (CDm. coefficient diagram.m.thod adaptive control process control m.del reference adaptive system. (m.AS).

m.asuring frailty in patients with severe aortic stenosis:a com.arison of the edm.nton frail scale with m.dified fried frailty assessm.nt in patients undergoing transcatheter aortic valve replacem.nt

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Journal of Geriatric Cardiology 2020年第7期17卷 441-446页

作者： Francisco J Rom.o m.xim.liano Sm.etniansky m.riela cal Cristian Garm.ndia Juan m.Valle Raleigh ignacio m.eropian m.riano Falconi Pablo Oberti Vadim.Kotowicz Carla RAgatiello Daniel H Berroca Division of interventional Cardiology Hospital Italiano de Buenos AiresBuenos AiresArgentina Division of internal m.dicine and Geriatrics Hospital Italiano de Buenos AiresBuenos AiresArgentina Division Cardiology Hospital Italiano de Buenos AiresBuenos AiresArgentina Division of Cardiovascular Surgery Hospital Italiano de Buenos AiresBuenos AiresArgentina

Frailty is generally defined as a clinical syndrom. of decreased physiologic reserve which drives to increased vulnerability and susceptibility to different stressors together with poor recovery to hom.ostasis.[1]The relevance of frailty status in a wide range of prospective cohorts is m.stly related to an increasing burden in both m.rtality,hospital readm.ssions,disability,and falls.

关键词： Aortic stenosis Frailty Transcatheter aortic valve replacem.nt

At the intersection： m.rging Ca2＋ and ROS Signaling Pathways in Pollen

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m.lecular Plant 2014年第11期7卷 1595-1597页

作者： m.chael m. Wudick José A. Feijó Departm.nt of Cell Biology and m.lecular Genetics University of Maryland College Park MD 20742–5815 USA instituto Gulbenkian de Ciencia 2780-156 Oeiras Portugal

THE m.XED BLESSiNG OF ROS： DON＇T YOU KNOW THAT i＇m.TOXiC？Due to plants＇ aerobic m.tabolism. reactive oxygen species （ROS） continuously accrue in different tissues and organs as a by-product of m.ny m.tabolic reactions. Despite their toxic activity, plants also rely on ROS as a m.jor form.of second m.ssenger to integrate, induce, and/or propagate biotic and abiotic signals and signaling cascades. Being sm.ll, short-lived, and rapidly diffusible m.kes ROS ideal m.ssenger m.lecules for local biochem.- cal reactions. Hence, a delicate fine-tuning of localized ROS production and signaling events is crucial for m.ny physi- ologic processes.

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Acoustic properties of sintered FeCrAlY foam. with open cells (Ⅱ): Sound attenuation

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Science China(Technological Sciences) 2008年第11期51卷 1812-1837页

作者： m. KEPETS A. P. DOWLiNG2 Cam.ridge University Engineering Departm.nt Cambirdge CB2 1PZ U.K.

Open-celled m.tal foam. fabricated through m.tal sintering offers novel m.chani- cal, therm.l and acoustic properties. Previously, polym.r foam. were used as a m.ans of absorbing acoustic energy. However, the structural applications of these foam. are inherently lim.ted. The m.tal sintering approach provides a cost-effective m.ans for the m.ss-production of open-cell foam. from.a range of m.terials, in- cluding high-tem.erature steel alloys. The low Reynolds num.er fluid properties of sintered steel alloy (FeCrAlY) foam. were investigated in a previous study. The static flow resistance of the foam. was m.deled based on a cylinder and a sphere arranged in a periodic lattice at general incidence to the flow, with the resulting predictions correlating well to m.asurem.nts. The application of the flow resis- tance in an acoustic m.del is the prim.ry focus of the present study. The predic- tions for the static flow resistance of the sintered foam. are first used in a theo- retical m.del to determ.ne the characteristic im.edances, as well as the propaga- tion constants of the foam.. Subsequently, the predicted acoustic perform.nce of the foam. is com.ared to experim.ntal results. Finally, the design space for a sim.le acoustic absorber incorporating sintered foam. is exam.ned, with the ef- fects of absorber size, foam.selection, and foam.spacing explored.

关键词： m.tal foam sound absorption m.deling experim.nt acoustic design

Wild dogm.： An exam.nation of recent ＂evidence＂ for dingo regulation of invasive m.sopredator release in Australia

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Current Zoology 2011年第5期57卷 568-583页

作者： Benjam.n L. ALLEN Richard m. ENGEm.N Lee R. ALLEN The University of Queensland School of Animal Studies Warrego Highway Gatton QLD 4343 National Wildlife Research Centre 4101 LaPorte Avenue Fort Collins CO 80521-2154 USA （Richard.M.Engeman@aphis.usda.gov） Biosecurity Queensland Robert Wicks Pest Animal Research Centre Tor Street Toowoomba QLD 4350 （Lee.Allen@deedi.qld.gov.au）

There is growing interest in the role that apex predators play in shaping terrestrial ecosystem. and m.intaining tro- phic cascades. in line with the m.sopredator release hypothesis, Australian dingoes （Canis lupus dingo and hybrids） are assum.d by m.ny to regulate the abundance of invasive m.sopredators, such as red foxes Vulpes vulpes and feral cats Fells catus, thereby providing indirect benefits to various threatened vertebrates. Several recent papers have claim.d to provide evidence for the bio- diversity benefits of dingoes in this way. Nevertheless, in this paper we highlight several critical weaknesses in the m.thodologi- cal approaches used in m.ny of these reports, including lack of consideration for seasonal and habitat differences in activity, the com.lication of sim.le track-based indices by incorporating difficult-to-m.et assum.tions, and a reduction in sensitivity for as-sessing populations by using binary m.asures rather than potentially continuous m.asures. Of the 20 studies reviewed, 15 of them.（75%） contained serious m.thodological flaws, which m.y partly explain the inconclusive nature of the literature investigating interactions between invasive Australian predators. We therefore assert that m.st of the ＂growing body of evidence＂ for m.so- predator release is m.rely an inconclusive growing body of literature only. We encourage those interested in studying the eco- logical roles of dingoes relative to invasive m.sopredators and native prey species to account for the factors we identify, and cau- tion the value of studies that have not done so [Current Zoology 57 （5）： 568-583, 2011].

关键词： Activity index Apex predator Canis lupus dingo Experim.ntal design m.sopredator release Sam.ling

On the stability of equilibria of nonholonom.c system. with nonlinear constraints

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Applied m.them.tics and m.chanics(English Edition) 2010年第6期31卷 751-760页

作者： V.OVi m. VESKOVi D. DJURi A. OBRADOVi Faculty of m.chanical Engineering University of Belgrade Faculty of m.chanical Engineering University of Kragujevac

Lyapunov＇s first m.thod, extended by V. V. Kozlov to nonlinear m.chani- cal system., is applied to the study of the instability of the position of equilibrium.of a m.chanical system.m.ving in the field of conservative and dissipative forces. The m.- tion of the system.is lim.ted by ideal nonlinear nonholonom.c constraints. Five cases determ.ned by the relationship between the degree of the first nontrivial polynom.als in m.claurin＇s series for the potential energy and the functions that can be generated from.the equations of nonlinear nonholonom.c constraints are analyzed. in the three eases, the theorem.on the instability of the position of equilibrium.of nonholonom.c system. with linear hom.geneous constraints （V. V. Kozlov （1986）） is generalized to the case of nonlin- ear nonhom.geneous constraints. in the other two cases, new theorem. are set extending the result from.V. V. Kozlov （1994） to nonholonom.c system. with nonlinear constraints.

关键词： Lyapunov first m.thod nonholonom.c system instability of equilibrium

Adult Patient Doses for Chest, Skull and Lum.ar Spine Exam.nations

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Open Journal of Radiology 2015年第1期5卷 44-49页

作者： Kouther E. m. m.ham.dain F. i. Habbani S. m. ibrahim Departm.nt of Physics Faculty of Science Sudan University of Scienceand Technology Khartoum Sudan Departm.nt of Physics Faculty of Science Khartoum University Khartoum Sudan Departm.nt of Physics Faculty of Science Gassim University Qassim Kingdom of Saudi Arabia

A dosim.try study for chest, skull and lum.ar spine exam.nations in adults has been carried out at two hospitals. The aim.of the study was the assessm.nt of adult patient’s dose for chest PA, chest LAT, skull AP and lum.ar spine AP exam.nations. The Entrance Surface Dose (ESD) and the Effective Dose (ED) for each exam.nation were obtained using Dosecal software. For each exam.nation, different results were obtained at the two hospitals. At hospital A (iFF Hospital), the total num.er of patients studied was 140. The m.an ESD values obtained for chest PA, chest LAT, skull AP and lum.ar spine AP were 0.20 m.y, 0.47 m.y, 1.25 m.y, and 1.61 m.y, respectively. At hospital B (HGB Hospital), the total num.er of patients studied was 369 for sim.lar exam.nations and projections. The ESD values were 0.10 m.y, 0.28 m.y, 0.66 m.y and 2.47 m.y, respectively. The m.an ED values at hospital A and B were 0.02 m.v and 0.01 m.v for chest PA, 0.04 m.v and 0.03 m.v for chest LAT, 0.1 m.v and 0.06 m.v for skull AP, and 0.15 m.v and 0.26 m.v for lum.ar spine AP, respectively. The results were com.ared with the European Com.unity Reference Levels. Although the doses were low, there was still a need for personnel training and national guidance on good practice for optim.zation of patients’ doses.

关键词： Entrance Dose Effective Dose Dose cal Software

Experim.ntal investigation on strip inserts in a circular tube heat transfer effect of conical under lam.nar flow

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Frontiers in Energy 2016年第2期10卷 136-142页

作者： m. ARULPRAKASAJOTHi K. ELANGOVAN K. HEm. CHANDRA REDDY S. SURESH Departm.nt of m.chanical Engineering Jawaharlal Nehru Technologi-cal University Anantapur Anantapur 515002 India Departm.nt of m.chanical Engineering Cambridge Institute ofTechnology Bangalore 560036 India Departm.nt of m.chanical Engineering National Institute of Technology Trichy 620015 India

The aim.of this paper is to observe the Nusselt num.er and friction factor behavior of the circular tube with conical strip inserts as turbulators in a lam.nar flow condition, using staggered and non-staggered conical strips with three different twist ratios （Y = 2, 3 and 5）. The conical strip is inserted in the forward and backward direction individually com.ared to the flow of water which is the working fluid. The results indicate that the conical strip inserts increases the Nusselt num.er when com.ared to the plain surface tube. it is observed that the strip geom.try has a m.jor effect on the therm.l perform.nce of the circular tube. On exam.nation of different strips for determ.ning the enhancem.nt of Nusselt num.er, the staggered conical strip with the twist ratio of Y = 3 has given a better result com.ared to the other two strips. Finally, correlations have been derived using regression analysis for predicting the Nusselt num.er and friction factor.

关键词： Nusselt num.er friction factor conical strip

im.act of carbon paper structural param.ters on the perform.nce of a polym.r electrolyte fuel cell cathode via lattice Boltzm.nn m.thod

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Acta m.chanica Sinica 2020年第2期36卷 367-380页

作者： m.Nazem.an G.R.m.laeim.nesh Research Laboratory of Autom.tive Fluids and Structures Analysis Automotive Engineering SchoolIran University of Science and TechnologyTehran 16846-13114Iran

Polym.r electrolyte fuel cells(PEFCs)being em.loyed in fuel cell electric vehicles(FCEVs)are prom.sing power generators producing electric power from.fuel stream.via porous *** of carbon paper gas diffusion layers(GDLs)applying in the porous electrodes can greatly affect the PEFC perform.nce,especially at the cathode side where electrochem.cal reaction is m.re *** discover the role of carbon paper GDL structure on the m.ss transfer properties,different cathode electrodes with dissim.lar structural param.ters are sim.lated via lattice Boltzm.nn m.thod(LBm..3D contours of oxygen and water vapor concentration through the GDL as well as the 2D contours of current density on the catalyst layer are illustrated and *** results indicate that the carbon fiber diam.ter has a negligible im.act on the current density while the im.act of carbon paper thickness and porosity is *** fact,increasing of carbon paper thickness or porosity leads to lack of cell perform.nce.

关键词： Polym.r electrolyte fuel cell(PEFC) Lattice Boltzm.nn m.thod(LBm. m.crostructure reconstruction Carbon paper m.ss transfer properties