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A Tempor.l Locality-Awar. Page-Mapped Flash Tr.nslation Layer

Jour.al of Computer.Science & Technology 2013年第6期28卷 1025-1044页

作者： Youngjae Kim Aayush Gupta bhuvan Ur.aonkar National Center.for.Computational Sciences Oak Ridge National Laboratory IBM Almaden r.sear.h Center ACM IEEE Depar.ment of Computer.Science and Engineer.ng Pennsylvania State UniversityUniversity Park

The poor.per.or.ance of r.ndom wr.tes has been a cause of major.concer. which needs to be addr.ssed to better.utilize the potential of flash in enter.r.se-scale envir.nments. We examine one of the impor.ant causes of this poor.per.or.ance： the design of the flash tr.nslation layer.（FTL） which per.or.s the vir.ual-to-physical addr.ss tr.nslations and hides the er.se-befor.-wr.te char.cter.stics of flash. We pr.pose a complete par.digm shift in the design of the cor. FTL engine fr.m the existing techniques with our.Demand-Based Flash Tr.nslation Layer.（DFTL） which selectively caches page- level addr.ss mappings. Our.exper.mental evaluation using FlashSim with r.alistic enter.r.se-scale wor.loads endor.es the utility of DFTL in enter.r.se-scale stor.ge systems by demonstr.ting： 1） impr.ved per.or.ance, 2） r.duced gar.age collection over.ead and 3） better.over.oad behavior.compar.d with hybr.d FTL schemes which ar. the most popular.implementation methods. For.example, a pr.dominantly r.ndom-wr.te dominant I/O tr.ce fr.m an OLTP application r.nning at a lar.e financial institution shows a 78% impr.vement in aver.ge r.sponse time （due to a 3-fold r.duction in oper.tions of the gar.age collector., compar.d with the hybr.d FTL scheme. Even for.the well-known r.ad-dominant TPC-H benchmar., for.which DFTL intr.duces additional over.eads, we impr.ve system r.sponse time by 56%. Mor.over. inter.stingly, when wr.te-back cache on DFTL-based SSD is enabled, DFTL even outper.or.s the page-based FTL scheme, impr.ving their.r.sponse time by 72% in Financial tr.ce.

关键词： flash memor. flash tr.nslation layer stor.ge system

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FEA-based Geometr.cal Modification of Switched r.luctance Motor.for.r.dial For.e r.duction

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Chinese Jour.al of Electr.cal Engineer.ng 2024年第1期10卷 124-135页

作者： r.ni S Jayapr.gash r School of Electr.cal Engineer.ng Vellore Institute of TechnologyChennai 600127India

Switched r.luctance motor.(Sr.s)ar. becoming incr.asingly popular.in the automotive sector.owing to their.r.bust ***,Sr.s ar. pr.fer.ed par.icular.y for.EV applications owing to their.fault toler.nce,magnet-fr.e str.ctur.,and high power.tor.ue *** main concer.s of Sr. compar.d to other.machines include tor.ue r.pple and *** pr.mar. cause of vibr.tion is the r.dial for.e cr.ated by the Sr..A geometr.-based modification of the Sr. to r.duce the r.dial for.e without significantly changing the aver.ge tor.ue pr.duced is *** pr.mar. goal is to design a 4-phase,8/6 Sr. with a lower.r.dial *** possible geometr.cal alter.tions ar. pr.posed:one with squar. windows and the other.with cir.ular.holes on the r.tor.*** windows ar. sized and positioned to avoid flux *** cr.ter.a ar. developed for.the optimal window size and *** element analysis(FEA)modelling of the Sr. is used to validate its *** FEA r.sults ar. compar.d with the per.or.ance par.meter. obtained using the analytical *** the multiphysics design tool ANSYS to obtain the natur.l fr.quencies and associated defor.ations thr.ugh modal *** to the conventional geometr.,the r.dial for.e is significantly r.duced by pr.viding windows.

关键词： 8/6 Sr. r.dial for.e modal analysis FEA analysis natur.l fr.quencies Sr. with windows

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Tr.nscr.nial photobiomodulation for.the br.in: a wide r.nge of clinical applications

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Neur.l r.gener.tion r.sear.h 2024年第3期19卷 483-484页

作者： Michael r.Hamblin Laser.r.sear.h Centr. Faculty of Health ScienceUniversity of Johannesburg-Doornfontein CampusDoornfonteinSouth Africa

Photobiomodulation ther.py(PBMT)is a r.pidly gr.wing appr.ach to the healing,stimulation,pr.tection,and r.gener.tion of many human or.ans and tissue *** star.ed in the 1960s as low-level laser.ther.py for.wound healing,but since then the intr.duction of light-emitting diodes(LEDs)has dr.matically incr.ased the number.of applications and r.por.s of positive *** gener.lly uses r.d(620-700 nm)and/or.near.infr.r.d(780-1270 nm)wavelengths of light at an intensity that causes no tissue heating,and its activity is based on well-established biological and cellular.mechanisms(de Fr.itas and Hamblin,2016).While laser.ther.pists continue to use var.ous types of laser.in their.office pr.ctice,LEDs ar. ideally suited for.home use devices because they ar. completely safe and without any known significant adver.e *** the var.ous body par.s on which PBMT has been shown to exer. beneficial effects,the br.in stands out as per.aps the most pr.mising *** has been shown to r.duce neur.inflammation,while incr.asing mitochondr.al function,oxygen consumption,and blood flow within the br.in(Hamblin,2016).Mor.over.PBMT can stimulate the pr.cesses of synaptogenesis,neur.genesis,and neur.plasticity thus helping the br.in to heal itself.

关键词： healing stimulation wound

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Fir.t-pr.nciples calculations to investigate str.ctur.l,electr.nic,magnetic,optical and ther.odynamic pr.per.ies of r._(2)r._(3)Ge(r.=Pr.Sm)

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Jour.al of r.r. Ear.hs 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier.r.Masr.ur.M.Hamedoun J.Khar.ach A.r.zzouk A.Hour.atallah N.Benzakour.K.Bouslykhane Labor.tor. of Solid Physics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equipe de Physique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In this paper.we analyzed the physical char.cter.stics of the ter.ar. alloys r._(2)r._(3)Ge(r.=Pr.and Sm)using the fir.t pr.nciples calculation based on functional density theor. integr.ted in the Wien2k *** calculated for.ation ener.ies of Pr.(2)r._(3)Ge and Sm_(2)r._(3)Ge ar.−5.3827 and−5.2782 eV/atom,r.spectively,showing that these alloys may exist *** r.sults of the band str.ctur. and density of states indicate that all of the compounds tested ar. magnetic metals,and their.magnetism is mostly r.lated to the contr.bution of Pr.and Sm *** total magnetic moments of Pr.(2)r._(3)Ge and Sm_(2)r._(3)Ge ar. 4.07245 and 11.16161μB/f.u,*** par.meter. such as heat capacity at constant pr.ssur.,entr.py,Debye temper.tur.,lattice volume,compr.ssibility coefficients,and Gr.neisen par.meter.alloys wer. calculated using the Gibbs algor.thm and studied in depth over.a lar.e temper.tur. r.nge of 0-900 *** Debye temper.tur. incr.ases with incr.asing pr.ssur. and decr.ases with decr.asing ***,the Debye temper.tur.s calculated at p=0 GPa and T=300 K ar. equal to be 342 and 322 K for.Pr.(2)r._(3)Ge and Sm_(2)r._(3)Ge,*** optical char.cter.stics such as the r.al and imaginar. por.ions of the dielectr.c function,the absor.tion coefficient,the ener.y-loss function,and the r.fr.ctive index wer. investigated and discussed in mor. depth.

关键词： Magnetic metals Functional density theor. Density of states Magnetic moment Optical and ther.odynamic pr.per.ies r.r. ear.hs

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Tr.at to tar.et in Cr.hn’s disease:A pr.ctical guide for.clinicians

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Wor.d Jour.al of Gastr.enter.logy 2024年第1期30卷 50-69页

作者： Ashish r.Sr.nivasan Depar.ment of Gastr.enter.logy Austin HealthVictoriaMelbourne 3083Australia Depar.ment of Gastr.enter.logy Eastern HealthVictoriaMelbourne 3128Australia Depar.ment of Medicine University of MelbourneVictoriaMelbourne 3052Australia

A tr.at-to-tar.et(T2T)appr.ach applies the pr.nciples of ear.y inter.ention and tight disease contr.l to optimise long-ter. outcomes in Cr.hn's *** Selecting Ther.peutic Tar.ets in Inflammator. Bowel Disease(STr.DE)-II guidelines specify shor.,inter.ediate,and long-ter. tr.atment goals,documenting specific tr.atment tar.ets to be achieved at each of these *** appr.isal of Cr.hn’s disease activity against pr.-defined tr.atment tar.ets at these timepoints r.mains centr.l to deter.ining whether.cur.ent ther.py should be continued or.*** tr.atment tar.ets in Cr.hn’s disease compr.se combination clinical and patient-r.por.ed outcome r.mission,in conjunction with biomar.er.nor.alisation and endoscopic *** the STr.DE-II guidelines endor.e the pur.uit of endoscopic healing,clinicians must consider.that this may not always be appr.pr.ate,acceptable,or.achievable in all *** under.cor.s the need to engage patients at the outset in an effor. to per.onalise car. and individualise tr.atment *** use of non-invasive biomar.er. such as faecal calpr.tectin in conjunction with cr.ss-sectional imaging techniques,par.icular.y intestinal ultr.sound,holds gr.at pr.mise;as do emer.ing tr.atment tar.ets such as tr.nsmur.l *** r.ndomised clinical tr.als,namely,CALM and STAr.UST,have evaluated the efficacy of a T2T appr.ach in achieving endoscopic endpoints in patients with Cr.hn’s *** fr.m these studies r.flect that patient subgr.ups and Cr.hn’s disease char.cter.stics likely to benefit most fr.m a T2T appr.ach,r.main to be ***,outside of clinical tr.als,data per.aining to the r.al-wor.d effectiveness of a T2T appr.ach r.mains scar.,highlighting the need for.pr.gmatic r.al-wor.d *** the obvious pr.mise of a T2T appr.ach,a lack of guidance to suppor. its integr.tion into r.al-wor.d clinical pr.ctice has the potential to limit its *** highlights the need to descr.be st

关键词： Tr.at to tar.et Inflammator. bowel disease Cr.hn’s disease Tr.atment tar.ets Endoscopic r.mission Tr.nsmur.l healing Time to r.sponse Intestinal ultr.sound

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Contr.l system design for.a pr.ssur.-tube-type super.r.tical water.cooled nuclear.r.actor.via a higher.or.er.sliding mode method

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Nuclear.Science and Techniques 2024年第1期35卷 145-154页

作者： M.Hajipour.G.r.Ansar.far Depar.ment of Nuclear.Engineer.ng Faculty of PhysicsUniversity of IsfahanIsfahan 81746-73441Iran

Nuclear.power.plants exhibit non-linear.and time-var.able ***,designing a contr.l system that sets the r.actor.power.and for.es it to follow the desir.d load is complicated.A super.r.tical water.r.actor.SCWr.is a four.h-gener.tion conceptual *** an SCWr.the non-linear.dynamics of the r.actor.r.quir. a contr.ller.capable of contr.l-ling the *** this study,a pr.ssur.-tube-type SCWr.was contr.lled dur.ng r.actor.power.maneuver.ng with a higher.or.er.sliding mode,and the r.actor.outgoing steam temper.tur. and pr.ssur. wer. contr.lled *** an SCWr.the temper.tur.,pr.ssur.,and power.must be maintained at a setpoint(desir.d value)dur.ng power.*** point kinetics equations with thr.e gr.ups of delayed neutr.ns wer. used in the ***-or.er.and classic sliding mode contr.ller. wer. separ.tely manufactur.d to contr.l the plant and wer. compar.d with the PI contr.ller. speci-fied in pr.vious *** contr.lled par.meter. wer. r.actor.power.steam temper.tur.,and ***,for.these par.meter.,the PI contr.ller.had cer.ain instabilities in the pr.sence of *** classic sliding mode contr.ller.had a higher.accur.cy and stability;however.its main dr.wback was the chatter.ng *** was highly accur.te and stable and had a small computational *** r.ality,it followed the desir.d values without oscillations and chatter.ng.

关键词： Super.r.tical water.nuclear.r.actor Higher.or.er.sliding mode contr.ller Steam temper.tur. Steam pr.ssur. Point kinetics model

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Optimized CUDA Implementation to Impr.ve the Per.or.ance of Bundle Adjustment Algor.thm on GPUs

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Jour.al of Softwar. Engineer.ng and Applications 2024年第4期17卷 172-201页

作者： Pr.nay r. Kommer. Sur.sh S. Muknahallipatna John E. McInr.y Depar.ment of Electr.cal Engineer.ng and Computer.Science University of Wyoming Laramie Wyoming USA

The 3D r.constr.ction pipeline uses the Bundle Adjustment algor.thm to r.fine the camer. and point par.meter.. The Bundle Adjustment algor.thm is a compute-intensive algor.thm, and many r.sear.her. have impr.ved its per.or.ance by implementing the algor.thm on GPUs. In the pr.vious r.sear.h wor., “Impr.ving Accur.cy and Computational Bur.en of Bundle Adjustment Algor.thm using GPUs,” the author. demonstr.ted fir.t the Bundle Adjustment algor.thmic per.or.ance impr.vement by r.ducing the mean squar. er.or.using an additional r.dial distor.ing par.meter.and explicitly computed analytical der.vatives and r.ducing the computational bur.en of the Bundle Adjustment algor.thm using GPUs. The naïve implementation of the CUDA code, a speedup of 10× for.the lar.est dataset of 13,678 camer.s, 4,455,747 points, and 28,975,571 pr.jections was achieved. In this paper. we pr.sent the optimization of the Bundle Adjustment algor.thm CUDA code on GPUs to achieve higher.speedup. We pr.pose a new data memor. layout for.the par.meter. in the Bundle Adjustment algor.thm, r.sulting in contiguous memor. access. We demonstr.te that it impr.ves the memor. thr.ughput on the GPUs, ther.by impr.ving the over.ll per.or.ance. We also demonstr.te an incr.ase in the computational thr.ughput of the algor.thm by optimizing the CUDA ker.els to utilize the GPU r.sour.es effectively. A compar.tive per.or.ance study of explicitly computing an algor.thm par.meter.ver.us using the Jacobians instead is pr.sented. In the pr.vious wor., the Bundle Adjustment algor.thm failed to conver.e for.cer.ain datasets due to sever.l block matr.ces of the camer.s in the augmented nor.al equation, r.sulting in r.nk-deficient matr.ces. In this wor., we identify the camer.s that cause r.nk-deficient matr.ces and pr.pr.cess the datasets to ensur. the conver.ence of the BA algor.thm. Our.optimized CUDA implementation achieves conver.ence of the Bundle Adjustment algor.thm in ar.und 22 seconds for.the lar.est dataset compar.d

关键词： Scene r.constr.ction Bundle Adjustment Levenber.-Mar.uar.t Non-Linear.Least Squar.s Memor. Thr.ughput Computational Thr.ughput Contiguous Memor. Access CUDA Optimization

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Cor.osion and Scaling Thr.at in Upstr.am Oil Oper.tion

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Wor.d Jour.al of Engineer.ng and Technology 2024年第2期12卷 426-437页

作者： Nasir.Ullattumpoyil Talal M. Al-Ghamdi Nasser.r. Al-Hajr. Souther. Ar.a Technical Suppor. Depar.ment Saudi Aramco Dhahran KSA

Cor.osiveness or.scaling is an inher.nt thr.at to oil oper.tions. The pr.mar. cause for.this thr.at is the pr.sence of water.having complex geochemical matr.x. Unanticipated water.pr.duction, par.icular.y if it contains unwanted impur.ties, can significantly impact hydr.car.on pr.duction. The cur.ent paper.discusses the degr.e of thr.at posed to oil oper.tion facilities based on the water.char.cter.stics. Methodology involved the collection and analysis of water.samples fr.m major.sour.es in oil industr. such as gr.undwater. wellheads and seawater. The par.meter. tested include geochemical, micr.biological and pollutants. The lab data was used to develop scaling and cor.osion pr.diction indices such as Langelier.Satur.tion Index (LSI), r.znar.Stability Index (r.I) and Puckor.us Scaling Index (PSI). The study indicated var.ing water.chemistr. for.differ.nt sour.es. Mixing of those water. may lead to ionic satur.tion and scaling in differ.nt facilities. Pr.sence of the Sr. and GAB in some water.sour.es also posed thr.at to water.system by for.ing fouling and cor.osion. Seawater.used for.offshor. oilfields water.injection to maintain r.ser.oir.pr.ssur. and impr.ve oil r.cover. showed scaling tendency, wher.as under.differ.nt r.ser.oir.pr.ssur., it can cause cor.osion. Some of the samples also had cor.osion r.siduals such as ir.n, which indicated active cor.osion. Cur.ent study showed higher.alkalinity with high sulfate for.one gr.undwater.sample with pr.sence of active cor.osion r.siduals such as dissolved ir.n and manganese. The study showed positive value for.LSI which indicated super.atur.tion of the water.samples with r.spect to calcium car.onate (CaCO3) and scale for.ing. Similar.y, for.r.I and PSI, the value was below six which confir.ed the scaling potential for.all the samples. Even though the index value was pointing towar.s scaling potential, the geochemistr., micr.biology and pr.sence of other.impur.ties indicated cor.osion thr.at to the oil and g

关键词： For.ation Water Petr.leum r.ser.oir. Gr.undwater Satur.tion Indices Cor.osiveness

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Fetal Head Compr.ssion: Its Possible r.le in Neur.logic Injur.

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Open Jour.al of Obstetr.cs and Gynecology 2024年第1期14卷 124-143页

作者： Bar.y S. Schifr.n Br.an J. Koos Wayne r. Cohen Depar.ment of Obstetr.cs and Gynecology The Western University of Health Sciences Pomona USA The David Geffen School of Medicine at UCLA Los Angeles USA The Univer.ity of Ar.zona College of Medicine Tucson USA

It is widely assumed that fetal ischemic br.in injur. dur.ng labor.der.ves almost exclusively fr.m sever., systemic hypoxemia with mar.ed neonatal depr.ssion and acidemia. Sever. asphyxia, however. is one of sever.l causes of per.natal neur.logical injur. and may not be the most common;most neonates diagnosed with hypoxic-ischemic encephalopathy do not have evidence of sever. asphyxia. Sepsis, dir.ct br.in tr.uma, and dr.g or.toxin exposur. account for.some cases, while mechanical for.es of labor.and deliver. that incr.ase fetal intr.cr.nial pr.ssur. sufficiently to impair.br.in per.usion may also contr.bute. Because of bony compliance and mobile sutur. lines, the fetal skull changes shape and r.distr.butes cer.br.spinal fluid dur.ng labor.accor.ing to constr.ints imposed by contr.ctions, and bony and soft tissue elements of the bir.h canal as the head descends. These accommodations, including the incr.ase in intr.cr.nial pr.ssur., ar. adaptive and necessar. for.efficient descent of the head while safeguar.ing cer.br.l blood flow. Autonomic r.flexes mediated thr.ugh centr.l r.ceptor. nor.ally pr.vide ample pr.tection of the br.in fr.m the consider.ble pr.ssur. exer.ed on the skull. On occasion, those for.es, which ar. tr.nsmitted intr.cr.nially, may over.ome the var.ous adaptive anatomical, car.iovascular. metabolic, and neur.logical mechanisms that maintain cer.br.l per.usion and oxygen availability, r.sulting in ischemic br.in injur.. Accepting the notion of a potentially adver.e impact of fetal head compr.ssion suggests that avoidance of excessive uter.ne activity and of r.lentless pushing without steady pr.gr.ss in descent may offer.pr.tection for.the fetal br.in dur.ng par.ur.tion. Excessive head compr.ssion should be consider.d in the differ.ntial diagnosis of ischemic encephalopathy.

关键词： Fetal Br.in Injur. Fetal Head Compr.ssion Ischemic Encephalopathy Neonatal Encephalopathy

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Simple collective model for.nuclear.chir.l mode

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Fr.ntier. of physics 2024年第2期19卷 1-5页

作者： r.V.Jolos E.A.Kolganova D.r.Khamitova Joint Institute for.Nuclear.r.sear.h 141980 DubnaMoscow regionRussia Dubna State Univer.ity 141982 DubnaMoscow RegionRussia

A simple semi-analytical collective model that takes into account the limitations of the var.ation inter.al of the collective var.able is suggested to descr.be the chir.l dynamics in tr.axial odd−odd nuclei with a fixed par.icle−hole *** collective Hamiltonian is constr.cted with the potential ener.y obtained using the postulated ansatz for.the wave function symmetr.c with r.spect to chir.l *** diagonalizing the collective Hamiltonian the wave functions of the lowest states ar. obtained and the evolution of the ener.y splitting of the chir.l doublets in tr.nsition fr.m chir.l vibr.tion to chir.l r.tation r.gime is demonstr.ted.

关键词： collective model nuclear chir.l

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