简介：Threekeyfactorsarediscussed,whichaffectpositioningaccuracyofrange-rangepositioningmodeandhyperbolicpositioningmode.Basedontheerrorellipticaltheory,theexpressionsofpositioningerrorandofpositioninggeometricfactorofrange-rangepositioningmodeandhyperbolicpositioningmodearederived,andthepositioningerrorandtheblindpositioningareaoftwodifferentpositioningmodesareanalyzed.Accordingtotherequirementofnavigationarea,anoptimumpositional

简介：Researchontherangeanomalysuppressionalgorithminlaserradar(ladar)rangeimagesissignificantintheapplicationanddevelopmentofladar.Butmostofexistingalgorithmscannotprotecttheedgeandlineartargetwellwhilesuppressingtherangeanomaly.Aimingatthisproblem,thedifferencesamongtheedge,lineartarget,andrangeanomalyareanalyzedandanovelalgorithmbasedonneighborhoodpixelsdetectionisproposed.Firstly,therangedifferencesbetweencurrentpixelanditsneighborhoodpixelsarecalculated.Then,thenumberofneighborhoodpixelsisdetectedbytherangedifferencethreshold.Finally,whetherthecurrentpixelisarangeanomalyisdistinguishedbytheneighborhoodpixelnumberthreshold.Experimentalresultsshowthatthenewalgorithmnotonlyhasabetterrangeanomalysuppressionperformanceandhigherefficiency,butalsoprotectstheedgeandlineartargetpreferablycomparedwithotheralgorithms.

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简介：拥有路虎揽胜几乎是所有男人的梦想，不是因为它够大够让，能满足人们的虚荣心，而是其超常的通过能力和强劲的发动机几乎能征服一切坎途，而这种不畏险阻勇于挑战的精神似乎正是所有征服者的本性。

简介：当microsatellite技术发展，精确内部卫星的测量在分布式的卫星系统显示出它的意义。在这封信，一种新奇技术为测量内部卫星的距离被建议，它采用optoelectronic回声并且有功能自我引用。回声洞有高度光谱纯净和高摆动频率。由利用积聚的扩大原则把距离的测量变换成频率的，高精确性被完成。在实验，这个测量计划有在1和6km之间的一个大测量范围(能潜在地更大)，并且精确性比1.5m好。相对精确性到达1010的水平。

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简介：Thispaperstressesthenecessityofdefiningrangeofurbanforestandprovidesthebasisforreasonablydeterminingrangeofurbanforestandsomebasicprinciplestobefollowed.

简介：Inthispaperthedevelopmentofthetechnologyofthelaserscanningissummarized.Theprinciplesoflaserrangescanningareintroduced.Basedonthelaserscanningtechnologyandmethods,whichareinvestigatedbytheauthorstosurveydepositvolume,asurveyingsystemisdevelopedandapracticalapplicationisperformed.Itisshownthatthelaser-scanningtechnologyhasobviousadvantagessuchasmeasurementprecision,automationandvisualizationofobserveddataincomparisonwiththetraditionalmethods.Asaresult,laborintensityisrelievedobviouslyandworkefficiencyispromoted.

简介：LSTOMPOWERHYDROhasannouncedthelaunchofacompleteminihydrosolution.NamedMini-Aqua,theproducthasbeendevelopedtointegratethehydroturbine,generatorandcontrolsysteminasingleandoptimisedproduct.

简介：ArangesurveydatabaseisestablishedandusedtostudythedepositionorerosionprocessesintheLowerYellowRiver(LYR).Thehugeamountofdataobtainedthroughrangesurveysovernearly50yearsismanagedbysoftware(RGTOOLS)developedforthisstudy.RGTOOLSisalsousedtoevaluatetheamountanddistributionofdepositionorerosioninLYR.Volumetricmethodisusedforcomputationoftheamountofdeposition.Spatialandtemporalvariationsofthedepositionarestudiedandillustratedwithdrawings.Itisfoundthatatotalof6.44billionm3ofsedimentweredepositedinthelowerYellowRiveroverapproximately50years.Thepatternofdepositionvariesinresponsetothevariationofoncomingflow,whichisinfluencedbynaturalclimaticvariationsandalsobyreservoiroperation.

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简介：陆虎品牌一向以性能卓越著称，2003款RarlgeRoverHSE更是具有无与伦比的越野能力和公路行驶的绝佳性能。外观新型RarigeRoverHSE将以2003款RatlgeRover的身份在北美上市．它是陆虎在31年中推出的第三个全新的RatlgeRovet。新款RatlgeRover对其原本就与众不同的外观设计做了更大的改进。通过采用风格独特的前照灯和尾灯．独特的发动机进气槽和干净利落的曲面．造就了RatlgeRover独树一帜的造型设计风格。

简介：AbstractBackgrounds:Cervical posterior decompression surgery is used to relieve ventral compression indirectly by incorporating a backward shift of the spinal cord, and this indirect decompression is bound to be limited. This study aimed to determine the decompression limit of posterior surgery and the effect of the decompression range.Methods:We retrospectively reviewed the data of 129 patients who underwent cervical open-door laminoplasty through 2008 to 2012 and were grouped as follows: C4-C7 (n = 11), C3-C6 (n = 61), C3-C7 (n = 32), and C2-C7 (n = 25). According to the relative location of spinal levels within a decompression range, the type of decompression at a given level was categorized as external decompression (ED; achieved at the levels located immediately external to the decompression range margin), internal decompression (ID; achieved at the levels located immediately internal to the decompression range margin), and central decompression (CD; achieved at the levels located in the center, far from the decompression range margin). The vertebral-cord distance (VCD) was used to evaluate the decompression limit. The C2-C7 angle and VCD on post-operative magnetic resonance images were analyzed and compared between groups. The relationship between VCD and decompression type was analyzed. Moreover, the relationship between the magnitude of the ventral compressive factor and the probability of post-operative residual compression at each level for different decompression ranges was studied.Results:There was no significant kyphosis in cervical curvature (>-5°), and there was no significant difference among the groups (F = 2.091, P = 0.105). The VCD of a specific level depended on the decompression type of the level and followed this pattern: ED < ID < CD (P < 0.05). The decompression type of a level was sometimes affected by the decompression range. For a given magnitude of the ventral compressive factor, the probability of residual compression was lower for the group with the larger VCD at this level.Conclusions:Our study suggests that the decompression range affected the decompression limit by changing the decompression type of a particular level. For a given cervical spinal level, the decompression limit significantly varied with decompression type as follows: ED < ID < CD. CD provided maximal decompression limit for a given level. A reasonable range of decompression could be determined based on the relationship between the magnitude of the ventral compressive factor and the decompression limits achieved by different decompression ranges.

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简介：1IntroductionPetrogenesisofMesozoicgranitoidsinMongoliathatcomprisetheMongol-Okhotskfoldbeltwasstudiedduringmorethan40years.ThisbeltiswellknownprovinceoftheMesozoicmagmatismandmineralizationincludinggold,copperandmolybdenum,tinandtungsten,leadandzinc,andfluorite.Inthemiddleofthe1950'sChenGuodaproposedthediwatheorytoexplaintectonicactivityinChineseplatform.InRussianFarEastforsimilarprocessestheactivization(revivation)theorywasproposedwhichexplainedintracontinentaleventsintheMongol-okhotskfoldbwlt.

简介：Wepresentanovelandsimplemethodtoobtainanultrawidefreespectralrange(FSR)siliconringresonatortogetherwithatuningrangecoveringtheentirespectrumfrom1500to1600nm.AringresonatorwithalargeFSRtogetherwithahighQfactor,hightuningefficiency,andlowfabricationcostandcomplexityisdesiredformanyapplications.Inthispaper,weintroduceanovelwaytomakesucharingresonator,whichtakesadvantageofthewell-knownresonance-splittingphenomenon.ItisasingleringresonatorwithanFSRofmorethan150nmaround1550nmandwhichhasaneasythermo-optictunabilitythatcanproduceatuningrangearound90nmorevenmore.Moreover,thedeviceissimpletoimplementandcanbefabricatedinstandardcomplementarymetal-oxidesemiconductortechnologywithoutrequiringanykindofcomplicatedprocessingorextramaterials.Thepotentialapplicationsincludesinglemodelasercavities,wavelengthdivisionmultiplexingfilters,(de)multiplexers,opticalsensors,andintegratedreflectors.

简介：Todaythecowboyseemstobegivingupwearingthebandannahandkerchief.Perhapshethinksitmakeshimlooktoomuchlikeamoviecowboy.Maybehehasfoundsomethingmoreusefultotakeitsplace.Butnotlongago,hefeltthatitwasalmostasnecessaryapartofhisoutfitasarope.Andithadalmostasmanydifferentuses.Hecouldnotgetalongwithoutit.

简介：Weproposeanddemonstrateamultifunctionallocation-dependentmetamaterialintheterahertz(THz)rangeinwhichtheunitcellconsistsoftwopairsofcoupledresonators.Experimentalandsimulationresultsofourdevicesrevealthatbothpairsofthecoupledresonatorswillkeeptheirindividualresonancemodeswhentheyjointogether.Thus,theoveralltransmissionspectrumisacombinationoffrequencyresponsespectraofitscorrespondingconstituentparts.Whilechangingthelocationsoftheinnerresonatorsinourstructure,controllablewidthoftransmissionwindowandchangeablenumberoftransmissiondipscanberealized.Ourdesignprovidesafeasiblestructureformultifunctionalmicroelectromechanicaldevices.

简介：A31kmlongrangedistributedopticalfiberRamanphotontemperaturesensor(DOFRPTS)systemhavebeendevelopedbasedontemperatureeffectoftheamplifiedspontaneousRamanscatteringinfiber,andusingfiberlaserasapumpedsource.Theresultsshowthattemperaturemeasuringuncertaintyis±2°C,temperatureresolutionis0.1°C,measurementtimeis432s,spatialresolutionislessthan4m.

简介：Themechanismofγ-rayradiationinducedabsorptionlossoftheopticalfiberinvisiblerangeisanalyzed.Accordingtothemechanism,thequantitativerelationbetweenlossinopticalfiberandγ-raycumulationdoseisfoundbyuseofmethodsofsolidphysicsandstatisticphysics.Thisquantitatierelationiscertifiedintermsoftheresultsofradiationexperiment.