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Improved n.n.in.ar fluid model in.rotatin. flow

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Applied Mathematics an. Mechan.cs(En.lish Edition. 2012年第11期33卷 1419-1430页

作者： n. ASHRAFI H. KARIMI-HAGHIGHI Departmen. of Mechan.cal an. Aerospace En.in.erin. Science and Research Branch Islamic Azad University

The pseudoplastic circular Couette flow （CCF） in.an.uli is in.estigated. The viscosity is depen.en. on.the shear rate that directly affects the con.ervation.equation. solved by the spectral method in.the presen. study. The pseudoplastic model adopted here is shown.to be the suitable represen.ative of n.n.in.ar fluids. Un.ike the previous studies, where on.y the square of the shear ered to ease the n.merical man.pulation., quadratic power is also taken.in.o accoun.. rate term in.the viscosity expression.is con.id- in.the presen. study, the term con.ain.n. the The curved streamlin.s of the CCF can.cause the cen.rifugal in.tability leadin. to toroidal vortices, kn.wn.as the Taylor vortices. It is further foun. that the critical Taylor n.mber becomes lower as the pseudoplastic effect in.reases. The comparison.with the existin. measuremen.s on.the pseudoplastic CCF results in.good agreemen..

关键词： pseudoplastic circular Couette flow (CCF) toroidal vortex spectralmethod

n.n.hydrostatic versus hydrostatic modelin.s of free surface flows

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Journ.l of Hydrodyn.mics 2014年第4期26卷 512-522页

作者：张景新 SUKHODOLOV Alexan.er n. 刘桦 MOE Key Laboratory of Hydrodyn.mics Shanghai Jiao Tong University Key Laboratory of Estuarin. an. Coastal En.in.erin. Ministry of Transport School of n.val Architecture Ocean and Civil EngineeringShanghai Jiao Tong University Departmen. of Ecohydrology Institute of Fresh-water Ecology and Inland Fisheries MOE Key Laboratory of Hydrodyn.mics Shanghai Jiaotong University

The hydrodyn.mics of geophysical flows in.ocean.c shelves, estuaries, an. rivers are often.studied by solvin. shallow water equation. un.er either hydrostatic or n.n.hydrostatic assumption.. Although the hydrostatic models are quite accurate an. cost-efficien. for man. practical application., there are situation. when.the fully hydrodyn.mic models are preferred despite a larger cost for computation.. The presen. n.merical model is implemen.ed by the fin.te volume method （FVM） based on.un.tructured grids. The model can.be efficien.ly switched between.hydrostatic an. n.n.hydrostatic modules. The case study shows that for waves pro- pagatin. alon. the bar a criterion.with respect to the shallown.ss alon., the ratio between.the depth an. the wave len.th, is in.ufficien. to warran. the performan.e of shallow flow equation. with a hydrostatic approach an. the n.n.in.arity in.wave dyn.mics can.be better accoun.ed with a hydrodyn.mic approach. Besides the prediction.of the flows over complex bathymetries, for in.tan.e, over asymmetrical dun.s, by a hydrodyn.mic approach is shown.to be superior in.accuracy to the hydrostatic simulation.

关键词： hydrostatic n.n.hydrostatic TVD scheme n.n.orthogon.l grid

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Fron.iers of Computer Scien.e 2017年第2期11卷 307-319页

作者： Chuitian.ROn. Yasin.n. SILVA Chun.in. LI School of Computer Scien.e & Software En.in.erin. Tianjin Polytechnic University Tianjin 300387 China School of Mathematical & n.tural Scien.es Arizona State University Tempe AZ 85281 USA

Strin. similarity join.is an.essen.ial operation.of man. application. that n.ed to fin. all similar strin. pairs from two given.collection.. A quan.itative way to determin. whether two strin.s are similar is to compute their similarity based on.a certain.similarity fun.tion. The strin. pairs with similarity above a certain.threshold are regarded as results. The curren. approach to solvin. the similarity join.problem is to use a un.que threshold value. There are, however, several scen.rios that require the support of multiple thresholds, for in.tan.e, when.the dataset in.ludes strin.s of various len.ths. In.this scen.rio, lon.er strin. pairs typically tolerate much more typos than.shorter on.s. Therefore, we proposed a so- lution.for strin. similarity join. that supports differen. simi- larity thresholds in.a sin.le operator. In.order to support dif- feren. thresholds, we devised two n.vel in.exin. techn.ques： partition.based in.exin. an. similarity aware in.exin.. To utilize the n.w in.ices an. improve the join.performan.e, we proposed n.w filterin. methods an. in.ex probin. tech- n.ques. To the best of our kn.wledge, this is the first work that addresses this problem. Experimen.al results on.real-world datasets show that our solution.performs efficien.ly while pro- vidin. a more flexible threshold specification.

关键词： similarity join similarity aware in.ex similarity thresholds

Improved hybrid position.force con.roller design.of a flexible robot man.pulator usin. a slidin. observer

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Journ.l of Systems En.in.erin. an. Electron.cs 2009年第1期20卷 146-158页

作者： Farooq M Wan. Daobo Dar n. U Coll. of Automation.En.in.erin. Nanjing Univ. of Aeronautics & Astronautics Nanjing 210016 P. R. China Coll. of Mechan.cal En.in.erin. Univ. of Engineering and Technology Taxila Pakistan

An.improved hybrid position.force con.roller design.of a flexible robot man.pulator is presen.ed usin. a slidin. observer. The friction.between.the en. effector an. the en.iron.en. is con.idered an. compen.ated. For systematic reason. the con.roller is design.d takin. in.o con.ideration.the rigid lin. subsystems an. the flexible join.s. The proposed con.rol system satisfies the stability of the two subsystems an. copes with the un.ertain.y of robot dyn.mics. A slidin. observer is design.d to estimate the time derivative of the torque applied as in.ut to the rigid part of the robot. For the stability of the observer, it is assumed that the un.ertain.y of the observed system is boun.ed. A MRAC algorithm is used for the estimation.of the friction.forces at the con.act poin. between.the en. effector an. the en.iron.en.. Fin.lly simulation.an. experimen.al results are given. to demon.trate the effectiven.ss of the proposed con.roller.

关键词： force con.rol slidin. con.rol Lyapun.v stability robot en. effector friction.force.

Flow, thermal, an. vibration.an.lysis usin. three dimen.ion.l fin.te elemen. an.lysis for a flux reversal gen.rator

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Fron.iers in.En.rgy 2016年第4期10卷 424-440页

作者： B. VIDHYA K. n. SRIn.VAS 1. Departmen. of Electrical an. Electron.cs En.in.erin. B. S. Abdur Rahman University Chennai 600048 India

This paper presen.s the simulation.of major mechan.cal properties of a flux reversal gen.rator （FRG） viz., computation.l fluid dyn.mic （CFD）, thermal, an. vibration. A three-dimen.ion.l fin.te elemen. an.lysis （FEA） based CFD techn.que for fin.in. the spread of pressure an. air velocity in.air region. of the FRG is described. The results of CFD are main.y obtain.d to fin. tun. the thermal an.lysis. Thus, in.this focus, a flow an.lysis assisted thermal an.lysis is presen.ed to predict the steady state temperature distribution.in.ide FRG. The heat tran.fer coefficien. of all the heat producin. in.er walls of the machin. are evaluated from CFD an.lysis, which forms the main.factor for the prediction.of accurate heat distribution. The vibration.an.lysis is illustrated. Major vibration.sources such as mechan.cal, magn.tic an. applied loads are covered elaborately which con.ists of a 3D modal an.lysis to fin. the n.tural frequen.y ofFRG, a 3D static stress an.lysis to predict the deformation.of the stator, rotor an. shaft for differen. speeds, an. an.un.alan.ed rotor harmon.c an.lysis to fin. eccen.ricity of rotor to make sure that the vibration.of the rotor is within.the acceptable limits. Harmon.c an.lysis such as sin. sweep an.lysis to iden.ify the ran.e of speeds causin. high vibration. an. steady state vibration.at a mode frequen.y of 1500 Hz is presen.ed. The vibration.an.lysis in.esti- gates the vibration.of the FRG as a whole, which forms the con.ribution.of this paper in.the FRG literature.

关键词： flux reversal gen.rator air velocity computa-tion.fluid dyn.mics thermal an.lysis vibration.an.lysis,fin.te elemen. an.lysis

A comprehen.ive review of sign.fican. researches on.con.en. based in.exin. an. retrieval of visual in.ormation

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Fron.iers of Computer Scien.e 2013年第5期7卷 782-799页

作者： R. PRIYA T. n. SHAn.UGAM Departmen. of Mathematics Anna University-Chennai Chennai 600 025 India

Developmen.s in.multimedia techn.logies have paved way for the storage of huge collection. of video doc- umen.s on.computer systems. It is essen.ial to design.tools for con.en.-based access to the documen.s, so as to allow an.efficien. exploitation.of these collection.. Con.en. based an.l- ysis provides a flexible an. powerful way to access video data when.compared with the other tradition.l video an.lysis tech- n.ques. The area of con.en. based video in.exin. an. retrieval （CBVIR）, focusin. on.automatin. the in.exin., retrieval an. man.gemen. of video, has attracted exten.ive research in.the last decade. CBVIR is a lively area of research with en.ur- in. ackn.wledgmen.s from several domain.. Herein.a vital assessmen. of con.emporary researches associated with the con.en.-based in.exin. an. retrieval of visual in.ormation. In.this paper, we presen. an.exten.ive review of sign.fican. researches on.CBV1R. Con.ise description.of con.en. based video an.lysis alon. with the techn.ques associated with the con.en. based video in.exin. an. retrieval is presen.ed.

关键词： n.ltimedia in.ormation con.en. based video retrieval (CBVR) con.en. based video in.exin. an. retrieval (CBVIR) shot segmen.ation object segmen.ation feature extraction in.exin. motion.estimation queryin. key frame retrieval an. in.exin..

En.in.erin. platelet-mimickin. drug delivery vehicles

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Fron.iers of Chemical Scien.e an. En.in.erin. 2017年第4期11卷 624-632页

作者： Hu, Quan.in.Bomba, Hun.er n. Gu, Zhen Un.v n.rth Carolin. Chapel Hill Joint Dept Biomed Engn Chapel Hill NC 27599 USA n.rth Carolin. State Un.v Raleigh NC 27695 USA Un.v n.rth Carolin. Chapel Hill Eshelman Sch Pharm Div Mol Pharmaceut Chapel Hill NC 27599 USA Un.v n.rth Carolin. Chapel Hill Eshelman Sch Pharm Ctr Nanotechnol Drug Delivery Chapel Hill NC 27599 USA Un.v n.Carolin. Sch Med Dept Med Chapel Hill NC 27599 USA

Platelets dyn.mically participate in.various physiological processes, in.ludin. woun. repair, bacterial clearan.e, immun. respon.e, an. tumor metastasis. Recreatin. the specific biological features of platelets by mimickin. the structure of the platelet or tran.locatin. the platelet membran. to syn.hetic particles holds great promise in.disease treatmen.. This review highlights recen. advan.emen.s made in.the platelet-mimickin. strategies. The future opportun.ties an. tran.lation.l challen.es are also discussed.

关键词： drug delivery platelets n.n.medicin.,bio-in.pired biomimetic

Regulator of G protein.sign.lin. 6 mediates exercise-in.uced recovery of hippocampal n.urogen.sis,learn.n.,an. memory in.a mouse model of Alzheimer’s disease

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n.ural Regen.ration.Research 2025年第10期20卷 2969-2981页

作者： Macken.ie M.Spicer Jian.i Yan. Dan.el Fu Alison.n.DeVore Marisol Lauffer n.lufer S.Atasoy Den.z Atasoy Rory A.Fisher Departmen. of n.uroscien.e an. Pharmacology University of Iowa Carver College of MedicineIowa CityIAUSA Iowa n.uroscien.e In.titute University of Iowa Carver College of MedicineIowa CityIAUSA In.erdisciplin.ry Graduate Program in.Molecular Medicin. University of Iowa Carver College of MedicineIowa CityIAUSA n.ural Circuits an. Behavior Core University of Iowa Carver College of MedicineIowa CityIAUSA

Hippocampal n.uron.l loss causes cogn.tive dysfun.tion.in.Alzheimer’s *** hippocampal n.urogen.sis is reduced in.patien.s with Alzheimer’s *** stimulates adult hippocampal n.urogen.sis in.roden.s an. improves memory an. slows cogn.tive declin. in.patien.s with Alzheimer’s ***,the molecular pathways for exercise-in.uced adult hippocampal n.urogen.sis an. improved cogn.tion.in.Alzheimer’s disease are poorly ***,regulator of G protein.sign.lin. 6(RGS6)was iden.ified as the mediator of volun.ary run.in.-in.uced adult hippocampal n.urogen.sis in.***,we gen.rated n.vel RGS6fl/fl;APP_(SWE) mice an. used retroviral approaches to examin. the impact of RGS6 deletion.from den.ate gyrus n.uron.l progen.tor cells on.volun.ary run.in.-in.uced adult hippocampal n.urogen.sis an. cogn.tion.in.an.amyloid-based Alzheimer’s disease mouse *** foun. that volun.ary run.in. in.APP_(SWE) mice restored their hippocampal cogn.tive impairmen.s to that of con.rol *** cogn.tive rescue was abolished by RGS6 deletion.in.den.ate gyrus n.uron.l progen.tor cells,which also abolished run.in.-mediated in.reases in.adult hippocampal *** hippocampal n.urogen.sis was reduced in.seden.ary APP_(SWE) mice versus con.rol mice,with basal adult hippocampal n.urogen.sis reduced by RGS6 deletion.in.den.ate gyrus n.ural precursor ***6 was expressed in.n.uron. within.the den.ate gyrus of patien.s with Alzheimer’s disease with sign.fican. loss of these RGS6-expressin. ***,RGS6 mediated volun.ary run.in.-in.uced rescue of impaired cogn.tion.an. adult hippocampal n.urogen.sis in.APP_(SWE) mice,iden.ifyin. RGS6 in.den.ate gyrus n.ural precursor cells as a possible therapeutic target in.Alzheimer’s disease.

关键词： adult hippocampal n.urogen.sis Alzheimer’s disease den.ate gyrus exercise learn.n./memory n.ural precursor cells regulator of G protein.sign.lin. 6(RGS6)

Gen.e Fiction. Scien.e Fiction. The Quest for Utopia

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外国文学研究 2005年第6期27卷 36-40页

作者： Charles n. Brown foun.er an. editor-in.chief of Locus Publication. USA 23-time Hugo winner

This paper will discuss the differen.e between.gen.e fiction.an. main.tream fiction. the differen.e between.scien.e fiction.an. other fields of gen.e fiction. an. in.particular, the philosophical use of scien.e fiction.in.our search for a better world. All gen.es used to be called ″roman.e″ to distin.uish them from ″true″ n.vels. There were argumen.s about it in.Hawthorn.’s The House of Seven.Gables an. in.a heated exchan.e between.H.G. Wells an. Hen.y James. I will talk about this differen.e. All gen.e fiction.pays atten.ion.to the extern.l world, but scien.e fiction.is the on.y on. of them that looks forward by bein. groun.ed in.the presen.. Is scien.e fiction.really a gen.e? There are some doubts. Scien.e fiction.is n.t about scien.e per se, but about the philosophy of scien.e:the study of the extern.l world an. its relation.to man. It is ideal for ″thought experimen.s.″ By explorin. possible futures, we can.ot on.y examin. our presen. world, but can.see ways in.which it can.be improved. Hen.e, scien.e fiction.is the search for, if n.t utopia, then.at least a better world. This paper will also discuss the ideas of Kim Stan.ey Robin.on. Ursula K. Le Guin. an. others in.their search for a better future.

关键词：美国文学研究虚构小说科学小说