简介:Thevehicleswithhighgravitycentrearemorepronetorollover.Thepaperdealswithamethodofdynamicsanalysisoffireengineswhichisanexampleofthesetypesofvehicle.AlgorithmsforgeneratingtheequationsofmotionhavebeenformulatedbyhomogenoustransformationsandLagrange’sequation.Themodelpresentedinthisarticleconsistsofasystemofrigidbodiesconnectedonewithanotherforminganopenkinematicchain.Roadmaneuverssuchasalanechangeandnegotiatingacirculartrackhavebeenpresentedasthemainsimulationswhenacarlosesitsstability.Themethodhasbeenverifiedbycomparingnumericalresultswithresultsobtainedbyexperimentalmeasurementsperformedduringroadtests.
简介:Thisstudyinvestigatesdata-processingmethodsandexaminestheprecipitationeffectongravitymeasurementsattheDaligravitynetwork,establishedin2005.High-qualitygravitydatawerecollectedduringfourmeasurementcampaigns.Tousethegravitydatavalidly,somegeophysicalcorrectionsmustbeconsideredcarefully.Wefirstdiscussdata-processingmethodsusingweightedleastsquaresadjustmentwiththeconstraintoftheabsolutegravitydatum.Resultsindicatethatthegravityprecisioncanbeimprovedifallabsolutegravitydataareusedasconstraintsandifcalibrationfunctionsofrelativegravimetersaremodeledwithintheobservationfunction.Usingthisdata-processingscheme,themeanpointgravityprecisionisbetterthan12lgal.Afterdeterminingthebestdata-processingscheme,wethenprocessthegravitydataobtainedinthefourmeasurementcampaigns,andobtaingravitychangesinthreetimeperiods.Resultsshowthatthegravityhasaremarkablechangeofmorethan50lgalinthefirsttimeperiodfromApr–Mayof2005toAug–Septof2007.Tointerpretthelargegravitychange,ameanwatermasschange(0.6minheight)isassumedintheETOPO1topographicmodel.Calculationsoftheprecipitationeffectongravityshowthatitcanreachthesameorderoftheobservedgravitychange.ItisregardedasamainsourceoftheremarkablegravitychangeintheDaligravitynetwork,suggestingthattheprecipitationeffectongravitymeasurementsmustbeconsideredcarefully.
简介:Thenon-tidalvariationgainedfromcontinuousgravityobservationsinstationsusuallyreflectstheregionalcontinuousgravitychanges.Inthispaperwefocusonstudyingthenon-tidalvariationofBaijiatuanstation,Beijingwheretherearetwodifferentgravimeters(namely,L&R-804andPET-031).Basedontheoriginalrawtidalrecordsoftwogravimetersfrom2008to2011,wefirstremovevariousinterferencefromrawdatabythestandardproceduresoftware-Tsoft;thenwemodelthesolidearthtides,oceantidalloadingandpoletidethroughrelatedparameters;afterthatweadoptanewsegmentedpolynomialfittingmethodbasedonTsofttofitthecomplexdriftofspringgravimeter;andfinallywecalculatetheatmosphericloadingeffectsbyalinearregressionmodel.Afteraseriesofprocessingwegainthenon-tidalvariationofthetwogravimetersatBaijiatuansite,Beijing.Furthermore,toanalyzethenon-tidalvariationpreliminarily,westudythemaincomponentofrelatedtidaldatabypowerspectraldensity.Comparingthenon-tidalvariationoftwodifferentgravimeters,wefindseasonalfluctuationsinnon-tidalresults,whichareinaccordancewiththewaterstoragechange.Therefore,wetakeintoaccounttherelevanceofgravitychangesandwaterstoragebasedonthegravitydataofGRACEandwaterdataoftheCMAPmodelfrom2003to2011atdifferentsitesintheChinesemainland(Beijing,Chengdu,ShenyangandShiquanhe),andmakeapreliminaryanalysisontherelationshipbetweengravitychangesandwaterstorage.
简介:作为要学习的区域拿欧洲的主要陆地,新卫星重力技术的潜力:追踪的satellite-to-satellite(SST)并且与SST模型一起改进地区性的重力场模型的精确性被调查。这些模型的缺点被讨论。与是的GPM98C参考,几个另外的模型,的严肃异例剩余最近的SST全球重力场模型(EIGEN系列和GGM系列),被计算并且比较。在选择区域,有期刊性质的一些系统的错误在EIGEN和GGM存在的比较表演的结果是在高度和顺序的S系列模型。没在经典严肃模型被显示出的一些信息在EIGEN和GGM的S系列模型的低、中间的度和顺序被检测。最后,SST模型的有效的最大的度和订单被建议。
简介:我们为f(T)严肃理论在宇宙论的限制的精确上探索SandageLoeb(SL)测试的影响。因为它在远类星体的系列在Lyman-森林里测量redshift飘移,SL测试是对当前的宇宙论的观察的重要补充,盖住2z的redshift沙漠5。避免数据矛盾,当模仿30的基准的模型嘲笑SL测试数据,我们基于当前的联合观察数据使用最好合适的模型。我们确定为f(T)严肃理论的参数评价上的这些SL测试数据的影响。二个典型f(T)模型被考虑,幂定律模型f(T)PL和指数形式的模型f(T)终止。结果证明SL测试罐头有效地打破存在在在另外的宇宙论的观察的今日的事密度m和小瘤常数H0之间的强壮的退化。为考虑f(T)模型,SL测试的30年的观察能极其改进m和H0的限制精确,但是不能有效地改进模型参数的限制精确。
简介:Thispaperaimsatinvestigationofthedynamicpropertiesofgravitycageexposedtowavesbyuseofanumericalmodel.Thenumericalmodelisdeveloped,basedonlumpedmassmethodtosetuptheequationsofmotionofthewholecage;meanwhilethesolutionsofequationsaresolvedbytheRunge-Kutta-Vernerfifth-orderandsixth-ordermethod.Physicalmodeltestshavebeencarriedouttoexaminethevalidityofthenumericalmodel.Theresultsbythenumericalsimulationagreewellwiththeexperimentaldata.
简介:这份报纸在小粒的固体的体积回答上检验严肃的影响。在这研究的装载情形包括限制压缩,杆穿入进小粒的媒介并且通过一个孔排出。类似的装载和流动条件是可能的在表土在在situ资源利用过程包括的地球外的探索活动受到的压力和变丑政体被遇到。球形、非球形的粒子用分离元素方法(DEM)被学习。虽然DEM逐渐地被用来为小粒的固体建模,模拟结果的小心的确认是相当稀罕的。因此除了探索严肃的效果,这份报纸也在陆上的状况下面把DEM模拟与实验作比较验证DEM是否能生产令人满意的预言。陆上的实验与大照顾被进行并且用DEM仔细模仿了。为粒子的关键机械、几何的性质在DEM模拟为使用在实验室测试被测量。一系列DEM计算然后在减少的严肃下面被执行在地球外的环境下面模仿这些实验。严肃没在限制压缩盒子中在力量传播上有显著效果,这被发现;在杆穿入的装载坡度与严肃线性地成正比;在地窖分泌物的集体流动率是比例的与减少严肃摆平严肃和休息增加的角度的根。这些调查结果与期望一致并且存在科学证据。
简介:Basedonunifiedequivalentharmonicloadingonseabedfoundationandenergyapproachsuggestedbytheauthors,thedevelopmentofdynamicporewaterpressureandstabilityofsoilfoundationforthevibrationofoceangravitystructuresexcitedbyrandomwaveloadingareanalysed.Itmaybeseenthatthepresentmethodforthestudyofdynamicproblemsofoceangravitystructuresoilfoundationsismorereasonableandconvenient.
简介:为测试作为这个区域拿中国,新卫星严肃技术的潜力,为改进地区性的重力场模型的精确性追踪的satellite-to-satellite被学习。与是的WDM94引用,三个模型,的严肃异例剩余最近二个优雅全球重力场模型(EIGEN_GRACE02S,GGM02S)并且EGM96,被计算并且比较。为在三个模型的剩余之中的差别的原因被讨论。在剩余之间的Thecomparison证明在选择区域,EIGEN_GRACE02S或GGM02S比在更低的度部分(不到110度)的EGM96好。通过模型严肃异例剩余的分析,另外,有期刊性质的一些系统的错误在EIGEN和GGM模型,的更高的度部分存在,这被发现结果能也在SST严肃数据的确认作为引用被拿。
简介:Spatialandtemporalvariationof gravity fieldinthecapitalregionChang-CaiHUA;(华昌才)YongGUO;(果勇)Duan-FaLIU;(刘瑞法)GangXIAO;(肖钢),J.T....
简介:Inthispaper,perturbationmethodandFourier-cosine-expansionmethodareusedtosolvea3-DnonlinearproblemofasupercavitatingflowinaninclinedfieldofgravityatlargeFroudenumbers.Byexpandingthevelocitypotentialintoapowerseriesofasmallparameter,theoriginal3-Dnonlinearproblemisreducedtoanumberof2-Dones.Thesolutionsofthefirstthreeordersarederivedindetailandexpressedintermsofthecompleteellipticintegralsofthefirstandsecondkinds.Thentheboundaryintegralequationmethodisappliedtogetthenumericalsolutionsforeachorder.Computationalresultsareprovidedforsupercavitatingflowspastconesundervariousflowconditions.