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  • 简介:Thisarticlepresentsagoodrobustandreal-timesystemschemeofthemobilerobotobstacledetectionandnavigation,whichprincipleofworkisbasedonthefeaturedescriptorSURF.Inthisscheme,firstly,theimageinformationofthemobilerobotpathwascapturedbythebinocularcamera;thenthefeaturepointswereextractedandcorrespondingmatchedusingSURFtothebinocularimagesastheundetectedobstacles;finallyfixedthepositionoftheobjectivebytheparallaxbetweenthematchingpointscombiningwiththebinocularvisioncalibrationmodel.Theoreticalderivationandexperimentalresultsshowthatthisschemeismoreaccurateforthedetectionandnavigationoftheinterestpoints.Ithasfastmatchingspeedandhighaccuracyandlowerror.So,ithascertainpracticaleffectandpopularizingvalueforthemobilerobotreal-timeobstacleavoidanceandnavigation.

  • 标签: 移动机器人 视觉导航 特征描述 实时避障 鲁棒性 障碍检测
  • 简介:中等范围的天气的欧洲中心从微波手足更健全的、高分辨率动力学手足预报重新分析过渡期间(时代过渡期间)气象学和大小更健全,并且在观察系统气味卫星的地球上监视仪器的臭氧被使用分析截止的动态、化学的特征低(关口)在在七月初2007的东北中国上的事件。结果在100300hPa显示出上层的温暖核心的气旋的极的同温层的起源,与塑造漏斗的对流顶层侵入进联系了就在COL中心上面中间对流层。列臭氧和臭氧侧面上的同温层的侵入的影响用卫星大小被调查。当COL的紧张在2007年7月10日达到顶点时,全部的列臭氧(TCO)增加到达了最大值(4070杜)。这能动态地被归因于两个对流顶层(75%)的降下并且向下越过对流顶层(25%)同温层的臭氧搬运。tropospheric臭氧侧面的分析在关口中心前在上层的前面区域附近越过对流顶层为充满臭氧的同温层的空气的不可逆的搬运/混合提供了证据。这臭氧侵入由上面的tropospheric风经历了下游的运输,导致由在从向经由南朝鲜的北日本海的华东延长的宽广区域上的1216杜的TCO的另外的增加。气象学的分析也在中间和更低的对流层在气旋的发展前显示出同温层的侵入的领先。

  • 标签: 中国东北地区 卫星观测 化学特性 对流层顶 数值天气预报 地球观测系统
  • 简介:ThisresearchaimstoinvestigatethewritingproficiencyofHongKongpre-serviceESLteachers,inparticularhowtheirwritingproficiencydiffersascharacterizedbydistinguishingfeaturesinherentinsuchteachers'writingperformances.Over120pre-serviceESLteachersfromvariousprogrammesinlocaluniversitiesinHongKongwererecruitedforthestudy.Resultsshowedthatthehighertheirwritinglevel,thebettertheyperformedinasettaskaswellasingrammaticalrangeandaccuracy.Thedifferentprogrammestheyenrolledincouldaffectthenumberofcohesivedevicestheytendedtouse.Modeandyearsofstudyhadaneffectontaskachievementandnumberofcohesivedevice.Pre-serviceteachersenrolledintheteachertrainingprogrammesonapart-timebasisoutperformedthoseenrolledonafull-timebasis.Teacherswithmoreteachertrainingoutperformednewlyadmittedpre-serviceteachers.TheresultsofthisstudycouldprovideempiricalevidenceforidentifyingdifferentlevelsofwritingproficiencyforHongKongpre-serviceESLteachers.Onthisbasis,thelinkbetweenthewritingproficiencyofpre-serviceESLteachersandtheirassessmentofstudentscriptscouldbesubsequentlyestablishedinafollow-upstudytoexploretheirdifferencesinscoringfocusesandstrategieswhenscoringstudents'writings.Thiscouldfurthercontributetoteacherevaluation,teachertrainingconcerninglanguageproficiency,andtheimprovementofteachers'assessmentliteracyinhigh-stakesandL2classroomwritingassessment.

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  • 简介:AbstractObjective:Neurosyphilis is challenging to diagnose, especially in patients with human immunodeficiency virus (HIV)/syphilis co-infection. The aim of this study was to profile the clinical features of neurosyphilis and evaluate the correlation between neurosyphilis and clinical or laboratory factors among patients with HIV/syphilis co-infection.Methods:We retrospectively analyzed the data of 479 HIV/syphilis co-infected patients examined between August 2009 and September 2018. A multivariate logistic regression model was used to identify factors correlated with neurosyphilis.Results:The overall prevalence of neurosyphilis was 21.7%. The prevalence of neurosyphilis differed among patients with primary (11.1%), secondary (20.1%), and latent syphilis (29.1%). The prevalences of neurosyphilis in patients with serological non-response and serofast patients were 26.1% and 6.3%, respectively, while 12.5% of patients with serological relapse had neurosyphilis. Patients with secondary and latent syphilis had serum rapid plasma reagin (RPR) titers (per unit) of 1.44-fold [95% confidence interval (CI): 1.08-1.93, P= 0.014] and 2.73-fold (95% CI: 1.49-5.00, P= 0.001), respectively, which increased the risk of confirmed neurosyphilis. Among patients with latent syphilis, a serum RPR titer of ≥1:32 and peripheral blood CD4 cell count of ≤350/mL were significantly associated with neurosyphilis, with adjusted odds ratios of 9.45 (95% CI: 1.86-48.03, P= 0.007) and 3.75 (95% CI: 1.11-12.66, P= 0.033), respectively.Conclusion:A serum RPR titer of ≥1:32 and a peripheral blood CD4 cell count of ≤350/mL have predictive value in screening for neurosyphilis among HIV-positive patients with latent syphilis.

  • 标签: human immunodeficiency virus syphilis neurosyphilis correlated factors
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  • 简介:Throughdensifiedsurfacesamplingofforaminiferaandaccurateelevationmeasurementalongthreetransectlinesinopen-coasttidalsalt-marshofJianchuan,particularsalt-marshforaminiferaassemblageswerefound.Thesalt-marshforaminiferaassemblagesaredistributedinwell-definedverticalzonationswithrespecttoelevationandcloselyparallelmarshfloralzonations.Atthetopoftheverticalzonationallforaminiferadisappearabruptlywhichareaccuratelylocatedatthehighesthighwaterdatum.Thisdistributionpatterncanbeusedtorelocateformersealevelsaccurately(toanaccuracyofwithin±5cm).Amodemregionalcriterionofforaminiferaforrelocatingtheformersealevelsinhighresolutioninourcountryisprovided,anddeficienciesofstudyingtheverticalzonationonlyinshelteredcoastsalt-marshabroadarefilledup.

  • 标签: Jianchuan of North Jiangsu Province open-coast
  • 简介:ItisanacceptedfactthatthemainsolidphasesupportforpotassiumintheSichuanBasinispolyhalite[K2MgCa2(SO4)4·2H2O]ratherthansylvineis(KCl)(GongDXetal.,2015).Themineraltypes,occurrencecharacteristicsandmetasomatismofthepolyhalitebearingore-bedwereidentifiedandtheoriginofthepolyhalitewasdiscussed.ThepolyhalitesampleswereobtainedfromthecoreofZ12,locatedinDalongVillage,Guang'anCityofcentralSichuan.Thesamplingdepthswere2974m(s-1),3023m(s-2)and3106m(s-3).Themicrobeamanalysisofback-scatteringimageswascarriedoutusingaShimadzuEPMA-1720Serieselectronprobemicro-analyzer,supplementedbyaquantitativespectrumanalysisthatdeterminedthemineraltypes.

  • 标签: FEATURES of MICRO-FABRIC the GENETIC study
  • 简介:Remnantoceanbasinisakeytounderstandtheplatesuturingandsubsequentupliftanderosionoforogen.TheBayofBengalBasin(BOBB)providesatypicalexampletoanalyzetheremnantoceanbasinstructures,evolution,andrelationshipsbetweendepositionalfillingandupliftingoftheHimalayanOrogen.Thirty-nineseismicprofilesaswellasintervalvelocitiesofwellBODC3wereusedtocompileisopachmapsofthebasin.Amongtheseismicdata,26seismicprofileswereappliedtoestablish8crosssections.Thecrosssectionssuggestthebasinisasymmetric,boundedtothewestbytheeasterncontinentalmarginofIndia(ECMI)withgraben-horstandtotheeastbytheSundaconvergencemargindominatedbytrench-arcsystem.TheBOBBischaracterizedbyaprominentdownflexurestructurescausedbyhugeamountofBengalfanturbiditesedimentsaccumulation.OurisopachmapsandchronologydatacollectedfromadjacentregionsrevealtheinitialdevelopmentandfastsouthwardgrowthoftheBengalfanwererelatedtotheearlyandmajorstageupliftanderosionoftheHimalayanOrogen,respectively.TheBOBBhasexperiencedacriticaltransitionfromanoceanbasintoaremnantoceanbasinatLateOligocene.SuchbasinstructuresandevolutionfeaturesindicatetheBOBBprovideswholerecordsofobliqueconvergenceoftheIndiaandAsiaplates,andtheearlyandmajorstageevolutionoftheHimalayanOrogen.

  • 标签: 原型盆地 海洋盆地 孟加拉湾 构造特征 喜马拉雅造山带 盆地构造演化
  • 简介:统计分析从1949~1996基于历史的记录在过去的50年西北太平洋台风的climatological特征被进行了。学习的目标包括年变化,到季节和紧张的分发,和运动的范畴。另外的调查用台风怎么以在紧张和来源区域之间的产生和关系的地理地点变化做的。大多数强壮的台风在125°E的水东方上发源,这被揭示,与来自马里亚纳群岛的最强壮的组一起。而且,打台风的分发关于季节和纬度被给。在点的中央压力的统计乍见陆地建议在浙江和福建的省上做landfalls的台风不比在华南经常,但是有相对高的紧张。

  • 标签: TROPICAL cyclone. noFthwest PACIFIC climatological FEATURES
  • 简介:Basedonthedataoftemperatureandsalinityofthe137°Esectioninthewintersandsummersfrom1967to1995,thegeo-strophiccurrentofthesectioniscalculatedandanalyzed,andthedriftingtracksofthesatellitetrackingdriftbuoydistributedonthe144°Esectionarealsoanalyzed.InlightofthesurfacedynamicheightdistributionintheCSKatlas,thispapercomparessomefeaturesoftheSubtropicalCountercurrent,theNorthEquatorialCurrentandtheNorthEquatorialCountercurrent.Themainresultsareasfollows:1.TheSubtropicalCountercurrent,theNorthEquatorialCurrentandtheNorthEquatorialCountercurrentarenotsimplesinglecurrents,buthavetwobranchesormore.Oneofthecommonfeaturesofthethreecurrentsmentionedaboveis"multi-branching"ofthecurrent.2.Thezonaldistributionoftheflowvelocitystructure,thealternateandintermittentoccurrenceoftheeastwardandwestwardflows,withashallowerflowlayerandbelongingtothesurfacefloworsubsurfacef

  • 标签: the SUBTROPICAL Countercurrent the NORTH EQUATORIAL
  • 简介:TheEastKunlunfaultzoneislocatedinthenorthernmarginoftheBayanHarblock.ThestudyofearthquakerupturebehaviorinthefaultzoneisofimportanceforunderstandingthefutureseismicriskinnorthwestSichuan.Anumberofgeologicalfieldinvestigations,typicalmicrotopographyDGPSmeasurementsandsampledatingshowthattheearthquakeactivityoftheEastKunlunfaultzoneextendstothenorthboundaryofZoigebasin,asegmentknownastheLuochasegmentofTazangfault.Inthesatelliteimage,thesegmentisseenclearlyasgrayandyellowstrips.Theearthquakedeformationzonemainlyfeaturesfaultscarp,valleysontheslope,offsetgulliesandterraces,lineardistributionofplants,waterfall,faultspring,faultsagpond,andlandslide,collapseandtalusassociatedwithsurfacerupturing.Thesephenomenaaredistributedintermittentlyalongthere-existingfaultandforma~50km-longinverseL-shapeddeformationzone.Faultactivitiescausedleft-lateraloffsetofgulliesandterraces,withhorizontaldisplacementconcentratedat5.5m~6m,18m~23m,68m~75m,and200m~220m,respectively.Therecentearthquakeoccurredbetween340±30~500±30BP.Themacroepicenterislocated5km~7kmnorthwestofBenduovillage,withmagnitudeofMW7.3~7.4,maximumcoseismicdisplacementof6m,horizontaldisplacement5.5m~6mandverticaldisplacement0.2m~0.5m,beinginaproportionof5∶1~10∶1.ThesephenomenashowthattheTazangfaultisthecausativefaultofthisearthquake.ThefaultisaHoloceneactivefaultandwasdominatedrecentlybyleft-lateralmovementwithasmallamountofthrustcomponentundercompressiveshearstress.ThischaracteristicissimilartothemovementinothersegmentsoftheEastKunlunfaultzone.Theresultsofthisstudysupportthe"continentalescape"model.

  • 标签: 东昆仑断裂带 地震危险性 故障原因 地表破裂 大地构造意义 破裂特征
  • 简介:氧化物分散加强了铜合金由于他们热、电的传导性,高温度的力量和微观结构稳定性的优秀联合是吸引人的。迄今为止,到他们的制造的state-of-art是内部氧化(IO)过程。在这份报纸,氧化铝分散加强了铜(ADSC)Cu-2.5vol%Al2O3的名字的作文的粉末被反应milling(RM)生产是一个在原处煤气固体的反应过程的过程。为电、机械的性质调查的体积ADSC合金被sintering并且此后获得热挤出。在热巩固过程以后,充分使增加密度的粉末协议能被获得。单个-Al2O3阶段和侧面拓宽效果根据X光检查衍射(XRD)的结果是明显的;ADSC的HRB坚硬能象95一样高;结果应该在铜矩阵在脱臼和谷物边界上被归因于nano-Al2O3的卡住的效果。ADSC合金的电的传导性是55%IACS(国际退火铜标准)。热巩固的材料的房间温度坚硬近似在在900点为1h退火以后被维持

  • 标签: 弥散强化铜合金 反应球磨 微观结构 高硬度 特征和 热分散
  • 简介:AbstractBackground:Glioma is the most common malignant brain tumor in adults. The standard treatment scheme of glioma is surgical resection combined alternative radio- and chemotherapy. However, the outcome of glioma patients was unsatisfied. Here, we aimed to explore the molecular and biological function characteristics of GPX7 in glioma.Methods:The multidimensional data of glioma samples were downloaded from Chinese Glioma Genome Atlas (CGGA). RT-qPCR method was used to identify the expression status of GPX7. Kaplan-Meier curves and Cox regression analysis were used to explore the prognostic value of GPX7. Gene Set Enrichment Analysis (GSEA) was applied to investigate the GPX7-related functions in glioma.Results:The results indicated that the expression of GPX7 in glioma was higher compared to that in normal brain tissue. Univariate and multivariate Cox regression analyses confirmed that the expression value of GPX7 was an independent prognostic factor in glioma. The GSEA analysis showed that GPX7 was significantly enriched in the cell cycle pathway, ECM pathway, focal adhesion pathway, and toll-like receptor pathway.Conclusions:The GPX7 was recommended as an independent risk factor for patients diagnosed with glioma for the first time and GPX7 could be potentially used as the therapy target in future. Furthermore, we attempted to explore a potential biomarker for improving the diagnosis and prognosis of patients with glioma.

  • 标签: GPX7 Glioma Biomarker Survival
  • 简介:Bead-on-plateCO2laserweldingof1000MPagradetransformationinducedplasticity(TRIP)steelwasconductedunderdifferentweldingpowers,weldingspeedsandshieldgases.Themacrostructuralandmicrostructuralfeaturesoftheweldedjointwereinvestigated.Theincreaseofweldingspeedreducedthewidthoftheweldbeadandtheporositiesintheweldbeadresultingfromthedifferentflowmodeofmeltedmetalinweldpool.ThedecreaseofweldingpoweroruseofshieldgasofheliumalsocontributedtothereductionofporosityinBead-on-plateCO2laserweldingof1000MPagradetransformationinducedplasticity(TRIP)steelwasconductedunderdifferentweldingpowers,weldingspeedsandshieldgases.Themacrostructuralandmicrostructuralfeaturesoftheweldedjointwereinvestigated.Theincreaseofweldingspeedreducedthewidthoftheweldbeadandtheporositiesintheweldbeadresultingfromthedifferentflowmodeofmeltedmetalinweldpool.Thedecreaseofweldingpoweroruseofshieldgasofheliumalsocontributedtothereductionofporosityintheweldbeadduetothealleviationofinducedplasmaformation,thusstabilizingthekeyhole.TheporosityformationintimatelycorrelatedwiththeevaporationofalloyelementMninthebasemetal.Thelaserweldedmetalhadsamemartensitemicrostructureasthatofwater-quenchedbasemetal.Theweldingparameterswhichincreasedcoolingrateallledtofinemicrostructuresoftheweldbead.

  • 标签: 二氧化碳激光焊接 塑性钢 宏观结构 微观结构