简介：Inordertoobtainthethreedimensional(3D)fluorescencespectradirectlyandrapidlybyinsituandinvivophytoplanktonmonitoring,aprototypeoceanlidarsystemwiththeabilityofmeasuring3Dfluorescencespectraisdeveloped,inwhichanopticalparametricoscillator(OPO)andagratingspectrometerareemployed.Usingthesystem,the3Dfluorescencespectraoffivetypicalred-tidespeciesintheEastChinaSeaaremeasuredinlab.Thepreliminaryexperimentalresultsshowthefeasibilityofmonitoringandclassifyingphytoplanktonbythisoceanlidar.

简介：Thepath-followingcontroloftheasymmetryunderactuatedunmannedsurfacevehicle(USV)underexternaldisturbancessuchasunknownconstantandirrationaloceancurrentsisdiscussed,andanadaptivesliding-modepath-followingcontrolsystemisproposed,whichcomprisesapath-variableupdatedlaw,amodifiedintegralline-of-sight(ILOS)guidancelawbasedonatime-varyinglookaheaddistanceandadaptivefeedbacklinearizingcontrollerscombinedwithsliding-modetechnique.AmoreaccurateUSVmodelwithouttheassumptionofhavingdiagonalinertiaanddampingmatricesisfirstpresented,aimingatimprovingtheperformanceofthepath-followingcontrol.Next,thecoordinatetransformationisadoptedtodecoupletheswaydynamicfromtherudderangle,andthepath-followingerrorsdynamicswithoutnon-singularproblemarepresentedinthemovingFrenet-Serretframe.Then,basedonthecascadedtheoremandtheadaptivesliding-modemethod,theadaptivecontrollawofpositionerrorsandcourseerroraredesigned,amongwhichthelookaheaddistanceandintegralgainareallcomputedasdifferentfunctionsofcross-trackerrortoestimateandcompensatethesideslipanglecausedbyexternaldisturbancesadaptively.Finally,accordingtotheLyapunovandcascadedtheorem,thecontrolsystemproposedisprovedtobeuniformgloballyasymptoticstability(UGAS)anduniformsemiglobalexponentialstability(USGES)whenthecontrolobjectivesareallachieved.Simulationresultsillustratetheprecisionandhigh-qualityperformanceofthisnewcontroller.