简介:监督分类法在遥感影像分类中应用广泛,结合已有地质资料和实测地质剖面信息,将研究区岩性分为苏维依组泥岩和粗砂岩,库姆格列木群泥岩、砾岩和含砾粗砂岩,巴什基奇克组粗砂岩和砾岩,巴西改组细砂岩等8个类型,运用ENVI提供的常用监督分类方法——最大似然法,对研究区的遥感影像进行岩性分类研究。并利用混淆矩阵分别对不同影像的分类结果进行精度评价,结果表明ZY-3影像的分类总体精度达到了78.65%,Kappa系数为0.7606,能够较好地进行岩性信息提取,具有较高的可靠性,可在地质调查工作中推广,能够有效地减少面积性地质测量工作,特别适用于岩石裸露程度较高的艰苦工作区。
简介:Thispaperpresentsasemi-empiricallumpedparametermodeldevelopedforanalysingthedynamicstabilityandperformancelimitationsofapressurecompensatedvanepumpforanautomotiveapplicationwithlow-costcomponents.Themodelcalculatescontinuousdisplacementchamberpressureprofilesandinertialeffectsforthedeterminationoftheinternalforcesactingonthevanepump'spivotingcam.Measurementsconductedonacustomteststandwereusedtodefineanonlinearlyprogressivebiasspringmodelandablackboxrepresentationofthepumpcontrolsystemvalves.Analysisofthecompletemodelrevealsthattheperformancelimitationsimposedbythecontrolsystemvalves,intermsofsystemstabilityandachievablecontrollerbandwidth,aremorerestrictivethanthelimitationsimposedbythelow-costvanepumpandlimitthethatbandwidthto1.84Hz.Thecontrolsystemalsoimposeslimitationstothesystemperformancebasedonresonancephenomenawhichmaybesignificantinsomeapplications.
简介:ThispapergivesatutorialonhowtoproveLyapunovtypecriteriabyoptimalcontrolmethods.Firstly,weconsiderstabilitycriteriaonHill'sequationswithnonnegativepotential.Byoptimalcontrolmethodsdevelopedin1990s,weobtainseveralstabilitycriteriaincludingLyapunov'scriterion,Ne..gauzandLidski'scriterion.Secondly,wepresentstabilitycriteriaonHill'sequationswithsign-changingpotentialinwhichBrog'scriterionandKrein'scriterionareincluded.
简介:Thispaperpresentsasemi-empiricallumpedparametermodeldevelopedforanalysingthedynamicstabilityandperformancelimitationsofapressurecompensatedvanepumpforanautomotiveapplicationwithlow-costcomponents.Themodelcalculatescontinuousdisplacementchamberpressureprofilesandinertialeffectsforthedeterminationoftheinternalforcesactingonthevanepump'spivotingcam.Measurementsconductedonacustomteststandwereusedtodefineanonlinearlyprogressivebiasspringmodelandablackboxrepresentationofthepumpcontrolsystemvalves.Analysisofthecompletemodelrevealsthattheperformancelimitationsimposedbythecontrolsystemvalves,intermsofsystemstabilityandachievablecontrollerbandwidth,aremorerestrictivethanthelimitationsimposedbythelow-costvanepumpandlimitthethatbandwidthto1.84Hz.Thecontrolsystemalsoimposeslimitationstothesystemperformancebasedonresonancephenomenawhichmaybesignificantinsomeapplications.
简介:摘要本文章简要讨论了在数学中有关圆的不遗漏、不重复的一些问题。通过典型例题与思维方法相结合,强调了师生不要忽视这种问题。
简介:Inthispaper,withthehelpofLyapunovfunctionalapproach,sufficientconditionsfortheasymptoticstabilityofzerosolutionforacertainfourthordernon-lineardelaydifferentialequationaregiven.