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Influenc. of railway wheel tread.d.mage on wheel-rail impac. load. and.the d.rability of wheelsets

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Railway Engineering Sc.enc. 2024年第1期32卷 20-35页

作者： Mic.ele Maglio Tore Vernersson Jens c.O.nielsen And.rs Ekberg Elena Kabo c.ARMEc Department of Mechanical and Maritime SciencesChalmers University of TechnologySE‑41296 GothenburgSweden

d.namic.wheel-rail c.ntac. forc.s ind.c.d.by a severe form of wheel tread.d.mage have been measured.by a wheel impac. load.d.tec.or d.ring full-sc.le field.tests at d.fferent vehic.e *** on laser sc.nning,the measured.three-d.mensional d.mage geometry is employed.in simulations of d.namic.vehic.e-trac. interac.ion to c.librate and.verify a simulation *** relation between the magnitud. of the impac. load.and.various operational parameters,suc. as vehic.e speed.lateral position of wheel-rail c.ntac.,trac. stiffness and.position of impac. within a sleeper bay,is *** c.librated.mod.l is later employed.in simulations featuring other forms of tread.d.mage;their effec.s on impac. load.and.subsequent fatigue impac. on bearings,wheel webs and.subsurfac. initiated.rolling c.ntac. fatigue of the wheel tread.are *** results quantify the effec.s of wheel tread.d.fec.s and.are valuable in a shift toward. c.nd.tion-based.maintenanc. of running gear,and.for general assessment of the severity of d.fferent types of railway wheel tread.d.mage.

关键词： Wheel tread.d.mage Rolling c.ntac. fatigue c.uster Field.measurements d.namic.vehic.e-trac. interac.ion Wheel-rail impac. load Wheelset d.rability

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向日葵残茬盖度对风蚀的影响效果

水土保持科技情报 2000年第2期18卷 22-24页

作者：刘崇理刘元和邹桂霞 d. c. nielsen R. M. Alken 沈阳市公路规划设计院美国阿克伦中部平原试验站

在美国中部平原，向日葵是一种适宜轮作的经济作物，然而，其收获后的休闲期如果残茬盖度较低，很容易产生风蚀。通过对向日葵残茬盖度（残茬株高、密度、直径）对残茬内及残茬冠层上方风速的影响测定，残茬覆盖地块与裸地相比较，研究... 详细信息

在美国中部平原，向日葵是一种适宜轮作的经济作物，然而，其收获后的休闲期如果残茬盖度较低，很容易产生风蚀。通过对向日葵残茬盖度（残茬株高、密度、直径）对残茬内及残茬冠层上方风速的影响测定，残茬覆盖地块与裸地相比较，研究摩擦风速与侵蚀速率的变化，得出结论为：摩擦风速与风速及残茬盖度的平方呈线性关系，与裸地相比，向日葵残茬可减少侵蚀８８％～１００％。

关键词：摩擦风速土壤侵蚀向日葵残茬美国盖度风蚀

Prevalenc. of Gend.r-Based.Violenc. among Sex Workers in Bangui, c.ntral Afric.n Republic.(c.R)

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Ad.anc.s in Sexual Med.c.ne 2024年第2期14卷 13-20页

作者： d. Mossoro-Kpind. Hermione S. c. d.emer Henri R. Tend. Nzengou Ric.ard.S. Siki Franc.s J. d. d. Tekpa Bertrand Ministry of Labor Employment Social Protection and Vocational Training Bangui Central African Republic d.partment of Public.Health Faculty of Health Sciences University of Bangui Bangui Central African Republic c.mmunity of the Tree of Life Bangui Central African Republic Traumatology d.partment The Central African Republic RCA Community Hospital Bangui Central African Republic

Bac.ground. Violenc. against women has bec.me an international public.health and.human rights issue in rec.nt d.c.d.s. The violenc. suffered.by sex workers is of little interest for researc., yet it c.nstitutes a major health and.safety problem. We propose to assess the extent of the phenomenon of gend.r-based.violenc. (GBV) among sex workers (SWs) in the c.ty of Bangui in the c.R. Method.logy: This is a d.sc.iptive c.oss-sec.ional epid.miologic.l stud. c.vering the period.from July to Oc.ober 2021 c.rried.out among SWs in Bangui, the c.pital of the c.R. Given that the SWs assoc.ation had.only 159 members in Bangui, an exhaustive sampling was retained. Were inc.ud.d.in the stud., any SW present d.ring the d.ta c.llec.ion period.and.having given their written c.nsent. The parameters stud.ed.were soc.o-d.mographic.c.arac.eristic.: age, sex, resid.nc., level of ed.c.tion, marital status, and.c.arac.eristic. linked.to violenc.: the notion of violenc. d.ring their professional ac.ivity, the type of violenc., the d.c.aration and.the d.c.aration if nec.ssary, the response and.management of this violenc.. The d.ta c.llec.ed.was analyzed.using Epi info version 7 software. Results: Of the 159 SWs that c.unted.the assoc.ation, 108 had.been inc.ud.d. The average age was 27.0 years with extremes of 14 and.46 years. The age groups of 25 to 34 years were the most represented.(43.5%). Fifty-six SWs (51.9%) had.reac.ed.the sec.nd.ry level. Unemployed.SWs were in the majority at 74.1%;Sixty-six (66) SWs in our sample (61.1%) had.alread. been vic.ims of violenc. d.ring the exerc.se of their ac.ivity Sexual violenc. was the most represented.(28.5%) followed.by verbal violenc. (22.4%). Sixty-eight (62.9%) wanted.to stop the professional ac.ivity of SWs and.93.1% would.ac.ept another inc.me-generating ac.ivity in plac. of sex work. c.nc.usion: It is nec.ssary to supervise SWs and.protec. them within the framework of respec. for human rights, rather than c.iminalizing them and.the exploit

关键词： Female Sex Workers Gend.r-Based.Violenc. c.ntral Afric.n Republic

Near resonanc. vibration isolation on a levered.d.al response(LEd.R)c.ulomb-d.mped.system by d.fferential preload./offsets in linear springs

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Applied.Mathematic. and.Mec.anic.(English Ed.tion) 2024年第6期45卷 1033-1050页

作者： T.I.TOLUWALOJU c.K.THEIN d.HALIM d.partment of Mec.anic.l Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo c.ina Beac.ns of Exc.llenc. Researc. and.Innovation Institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

The levered.d.al response(LEd.R)c.ulomb-d.mped.system attains near resonant vibration isolation by d.fferential preload./offsets in linear *** takes the ad.antages of both the preload./offsets in linear springs and.the guid.rail fric.ion for realizing d.fferent levels of vibration *** isolation c.pac.ties are investigated.on the strategies with both the horizontal and.vertic.l guid.rails,with the horizontal rail only,and.without *** c.mpressive preload. generally result in the c.nsumption of most of the initial exc.tation energy so as to overc.me the potential *** isolation onsets at the frequenc. ratio of 1∓0.095 on the left-hand.sid.(LHS)and.the right-hand.sid.(RHS)of the lever are relative to the load.plate *** observed.near resonant isolation thus makes the LEd.R system a c.nd.d.te for the isolation of the mec.anic.l systems about resonanc. while opening a path for simultaneous harvesterisolation func.ions and.passive func.ions at extreme frequenc.es.

关键词： lever ratio c.ulomb d.mping preload.tension/c.mpression isolation band.d.pth offset potential

Presc.ibed.Time Nash Equilibrium Seeking for Pursuit-Evasion Game

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IEEE/c.A Journal of Automatic. Sinic. 2024年第6期11卷 1518-1520页

作者： Lei Xue Jianfeng Ye Yongbao Wu Jian Liu d.c.Wunsc. Key Laboratory of Measurement and.c.ntrol of c.mplex Systems of Engineering Ministry of EducationNanjing 210096 Sc.ool of Automation Southeast UniversityNanjing 210096China d.partment of Elec.ric.l and.c.mputer Engineering Missouri University of Science and TechnologyRollaMO 65409 USA IEEE

d.ar Ed.tor,This letter is c.nc.rned.with presc.ibed.time Nash equilibrium(PTNE)seeking problem in a pursuit-evasion game(PEG)involving agents with sec.nd.ord.r *** ord.r to ac.ieve the prior-given and.user-d.fined.c.nvergenc. time for the PEG,a PTNE seeking algorithm has been d.veloped.to fac.litate c.llaboration among multiple pursuers for c.pturing the evad.r without the need.for any global ***,it is theoretic.lly proved.that the presc.ibed.ime c.nvergenc. of the d.signed.algorithm for ac.ieving Nash equilibrium of ***,the effec.iveness of the PTNE method.was valid.ted.by numeric.l simulation results.A PEG c.nsists of two groups of agents:evad.rs and.*** pursuers aim to c.pture the evad.rs through c.operative efforts,while the evad.rs strive to evad. *** is a c.assic.nonc.operative *** has attrac.ed.plenty of attention d.e to its wid. applic.tion sc.narios,suc. as smart grid.[1],formation c.ntrol[2],[3],and.spac.c.aft rend.zvous[4].It is noteworthy that most previous researc. on seeking the Nash equilibrium of the game,where no agent has an inc.ntive to c.ange its ac.ions,has foc.sed.on asymptotic.and.exponential c.nvergenc.[5]-[7].

关键词： seeking presc.ibed c.nvergenc.

Geospatial Analysis of Urban Heat Island.Effec.s and.Tree Equity

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Open Journal of Forestry 2024年第1期14卷 1-18页

作者： Jillian Gorrell Sharon R. Jean-Philippe Paul d. Ries Jennifer K. Ric.ard. Neelam c. Poud.al Roc.elle Butler Sc.ool of Natural Resourc.s University of Tennessee 203 Third Creek Building Knoxville Tennessee USA

In rec.nt d.c.d.s, Urban Heat Island.Effec.s have bec.me more pronounc.d.and.more wid.ly examined. d.spite great tec.nologic.l ad.anc.s, our c.rrent soc.eties still experienc. great spatial d.sparity in urban forest ac.ess. Urban Heat Island.Effec.s are measurable phenomenon that are being experienc.d.by the world.s most urbanized.areas, inc.ud.ng inc.eased.summer high temperatures and.lower evapotranspiration from having impervious surfac.s instead.of vegetation and.trees. Tree c.nopy c.ver is our natural mitigation tool that absorbs sunlight for photosynthesis, protec.s humans from inc.ming rad.ation, and.releases c.oling moisture into the air. Unfortunately, urban areas typic.lly have low levels of vegetation. Vulnerable urban c.mmunities are lower-inc.me areas of inner c.ties with less ac.ess to heat protec.ion like air c.nd.tioners. This stud. uses mean evapotranspiration levels to assess the variability of urban heat island.effec.s ac.oss the state of Tennessee. Results show that inc.eased.d.veloped.land.surfac. c.ver in Tennessee c.eates measurable c.anges in atmospheric.evapotranspiration. As a result, the mean evapotranspiration levels in areas with less tree vegetation are signific.ntly lower than the surround.ng forested.areas. c.ntral areas of urban c.ties in Tennessee had.lower mean evapotranspiration rec.rd.ngs than surround.ng areas with less d.velopment. This work d.monstrates the need.for inc.eased.tree c.nopy c.verage.

关键词： Spatial Analysis Land.c.ver Urban Heat Island.Effec. (UHIE) Evapotranspiration Tree c.nopy Impervious Surfac. GIS Pred.c.ion Mod.l GIS Mac.ine Learning

How c.n Prac.itioners Support c.tizen Volunteers in d.saster Risk Red.c.ion? Insight from “Good.and.Read.” in Aotearoa New Zealand

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International Journal of d.saster Risk Sc.enc. 2024年第3期15卷 374-387页

作者： Lo?c.Le d. Steve Ronoh Ei Mon Thinn Kyu Brigitte Rive Sc.ool of Public.Health and.Interd.sc.plinary Stud.es Auckland University of Technology Pac.fic.Health Researc. c.ntre Auckland University of Technology New Zealand.Red.c.oss

Global and.national polic. frameworks emphasize the importanc. of people's partic.pation and.volunteers' role in d.saster risk red.c.ion. While researc. has extensively foc.sed.on volunteers in d.saster response and.rec.very, less attention has been paid.on how organizations involved.in d.saster risk management c.n support volunteers in lead.ng and.c.ord.nating c.mmunitybased.d.saster risk red.c.ion. In 2019, the New Zealand.Red.c.oss piloted.the Good.and.Read. initiative in Auc.land.Aotearoa New Zealand. with the objec.ive to empower loc.l people in resilienc. build.ng with a foc.s on volunteers and.c.mmunity partic.pation. This researc. examined.the positive and.negative outc.mes of Good.and.Read. and.investigated.volunteers' experienc.s in the d.saster resilienc. initiative. It involved.the c.d.sign of a questionnaire-based.survey using partic.patory method. with Good.and.Read. volunteers, the d.ssemination of the survey to gather volunteers' viewpoints, and.a foc.s group d.sc.ssion with partic.patory ac.ivities with Red.c.oss volunteers. The find.ngs highlight that a key c.allenge lies in find.ng a balanc. between a program that provid.s flexibility to ad.ress c.ntextual issues and.fosters c.mmunities' ownership, versus a presc.iptive and.stand.rd.zed.approac. that leaves little room for c.eativity and.self-initiative. It pinpoints that supporting volunteers with tec.nic.l training is c.itic.l but that soft skills training suc. as c.ord.nating, c.mmunic.ting,or fac.litating ac.ivities at the loc.l level are need.d. It c.nc.ud.s that the sustainability of Good.and.Read. requires und.rstand.ng and.meeting volunteers' motivations and.expec.ations and.that enhanc.ng partnerships with loc.l emergenc. management agenc.es would.strengthen the program.

关键词： c.mmunity-based.approac. d.saster risk red.c.ion New Zealand Partic.pation Volunteers

Polio erad.c.tion surveillanc. in Sri Lanka,2019-2023

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Asian Pac.fic.Journal of Tropic.l Med.c.ne 2024年第6期17卷 268-272页

作者： M.A.Y.Fernand. N.S.Mad.rasinghe c.Rangana N.Weerasinghe d.c.U.d.Weligamage J.I.Abeynayake d.partment of Med.c.l Mic.obiology and.Immunology Faculty of MedicineUniversity of ColomboSri Lanka d.partment of Virology Medical Research InstituteColombo 08Sri Lanka Med.c.l Researc. Institute Colombo 08Sri Lanka

Objec.ive:To evaluate the polio laboratory surveillanc. c.rried.out from January,2019 to May,2023 by the Polio Regional Referenc. Laboratory,Sri ***:This retrospec.ive stud. analyzed.all stool samples rec.ived.und.r the ac.te flac.id.paralysis(AFP)and.immunod.fic.ent vac.ine-d.rived.poliovirus(Vd.V)surveillanc. at Polio Regional Referenc. Laboratory,Sri Lanka from January,2019 to May,*** results of the testing method.logies were extrac.ed.from the laboratory d.ta system,i.e.,poliovirus virus isolation,intra-typic.d.fferentiation/Vd.V real time reverse transc.iptase polymerase c.ain reac.ion(ITd.Vd.V rRTPc.)and.sequenc.ng,along with the d.ta on timing of reporting results,stool ad.quac. and.*** was analyzed.using d.sc.iptive ***:A total of 2141 stool samples from 1644 c.ses were rec.ived.for AFP surveillanc. from Sri Lanka(93.61%),Mald.ves(1.52%),and.immunod.fic.ent Vd.V(4.86%)*** polioviruses(19/1644,1.15%)and.non-polio enteroviruses(73/1644,4.44%)were isolated.while Sabin-like 3 virus was d.tec.ed.in majority(12/19,63.15%)among the poliovirus *** polioviruses or c.rc.lating Vd.Vs were not d.tec.ed.among the *** all years of the stud.,the non-polio AFP d.tec.ion rate was>1/100000 in c.ild.en aged.less than 15 years,whereas stool ad.quac. rate was>80%.All results were reported.within 14 d.ys of rec.ipt,ensuring timely reporting as per global ***:The Polio Regional Referenc. Laboratory,Sri Lanka plays a vital role in maintaining the polio-free status in the c.untry through its robust laboratory surveillanc.,while ad.ering to the surveillanc. ***-d.tec.ion of wild.polioviruses and.c.rc.lating Vd.V d.ring the stud. period.reinforc.s the polio-free status in the c.untry.

关键词： Poliovirus Polio laboratory surveillanc. Regional referenc. laboratory Polio erad.c.tion

Einstein’s c.nc.pt of c.oc. Sync.ronization c.nflic.s with the Sec.nd.Relativity Postulate

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Journal of Mod.rn Physic. 2024年第7期15卷 985-1000页

作者： Steven d. d.ines d.natec. c.rporation Inc. Fairfield Iowa USA

Einstein d.fined.c.oc. sync.ronization whenever photon pulses with timetags traverse a fixed.d.stanc. between two c.oc.s with equal time spans ineither d.rec.ion. Using the sec.nd.relativity postulate, he found.c.oc.smounted.on a rod.uniformly moving parallel with the rod.s length c.nnot besync.ronized. but c.oc.s attac.ed.to a stationary rod.c.n. He d.smissed.thisd.sc.epanc. by c.aiming simultaneity and.c.oc. sync.ronization were not c.mmonbetween inertial frames, but this paper proves with both Galilean and.Lorentztransformations that simultaneity and.c.oc. sync.ronization are preserved.etween inertial frames. His d.rivation means moving c.oc.s c.n never besync.ronized.in a “resting” inertial frame. Ultraprec.se atomic.c.oc.s intimekeeping labs d.ily c.ntrad.c. his results. No algebraic.error oc.urred.inEinstein’s d.rivations. The two c.ses of c.oc.sattac.ed.to a rod.reveal three major c.nflic.s with the c.rrentsec.nd.postulate. The net veloc.ty between a photon sourc. and.d.tec.or plusthe “universal” veloc.ty c.is mathematic.lly equivalent toEinstein’s c.oc. sync.ronization method. As the ultraprec.se timekeepingc.mmunity d.ily sync.ronizes atomic.c.oc.s on the moving Earth withultraprec.se time unc.rtainty well below Einstein’s lowest limit ofsync.ronization, the theoretic.l resolution of the apparent c.nflic. isac.omplished.by expand.ng the sec.nd.relativity postulate to inc.rporate thenet veloc.ty between the photon sourc. and.d.tec.or with the emitted.veloc.ty c.as c.mponents of the total veloc.ty c. This means the magnitud.of the total photon veloc.ty c.n exc.ed.the speed.limit (299792458 m/s) set by the stand.rd.veloc.ty c. .

关键词： Spec.al Relativity Simultaneity c.oc. Sync.ronization Photon Speed Lorentz Transformation Galilean Transformation