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简介：In2016,thepowersupplyinCSRmwasdigitalizedtofurtherimprovethereliabilityofoperation.Anewvectorrecticationtechniqueisdevelopedfortheresearchofadvancedpowersupplyandelectricalrelatedtechnologies.AnumberofEMCandelectricalsafetytestingitemsforHIMMWuweipowersupplieshasbeencompleted.DigitalizationupgradeofthepowersupplyCSRmpowersupply,including30setsquadrupolemagnetpowersupply,6setssextupolemagnetpowersupplyand8setsbipolarcorrectmagnetpowersupply,weretransformedbyusingofdigitalcontrollersbasedonFPGA.Fig.1displaysthemeasurementresultsofthenewdigitalpowersupplyofquadrupolemagnet,thecurrenterror(attop)was1.7610?5,thetrackinger-rorwas5.2810?5.Theperformanceandreliabilityofthepowersupplyhavebeengreatlyimproved.

简介：近来大家都在谈论面向21世纪的物理教育。从牛顿到爱因斯坦，标志着从经典物理到近代物理的转变，大约用了300年，知识更新的时间尺度以百年计。本世纪以来，科学技术的进步是加速发展的。如果说上半个世纪发展的时间常数还有三四十年，则下半个世纪已缩短

简介：自跟踪馈源网络被广泛应用在测控、通信、雷达系统中，作为核心部件，随着系统需求的日益增长，对自跟踪馈源的性能要求越来越高。在自跟踪馈源网络中，跟踪精度高、结构紧凑并具有良好定向性和耦合特性的TE2l模耦合器是最常见的设计选择之一。

简介：本文分析了现行高等师范院校物理教学模式存在的弊端与不足，然后从教学思想，教学观念，教学内容，教学方法以及教学手段诸方面提出了新的高师物理教学模式。

简介：2011年全国初中应用物理知识竞赛已落下帷幕，掩卷沉思，切实感受到试题具有贴近生活实际、突出物理知识应用、重视学生动手能力和科学探究的特点，有利于提高学生的科学素养，培养创新精神．

简介：Futuremultimediacommunicationsystemshavetosupporttheuser'sneeds,theterminalcapabilities,thecontentspecificationandtheunderlyingnetworkingtechnologies.Therelatedprotocolsandapplicationsmustbedesignedfromthisintegrationperspectiveinacross-layercentricmanner.Inthispaper,weproposeanimplementationofastreamingservice(e.g.,TelevisionoverIPservice)withaunifiedQoSmanagementconceptthatenablesanIPdrivenintegrationofdifferentsystemcomponents(terminal,user,content,andnetwork).TheMPEG-21frameworkisusedtoprovideacommonsupportforimplementingandmanagingtheend-to-endQoS.Themainfocusofthispaperisonthearchitecturedesign,protocolsspecificationandimplementationevaluation.PerformanceevaluationsusingPSNRandSSIMobjectivevideoqualitymetricsshowthebenefitoftheproposedMPEG-21-enabledcross-layeradaptation.

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简介：Singlecrystal(100)InPsamplesand(0001)GaNepitaxiallayerswereirradiatedattheHeavyIonResearchFacilityinLanzhou(HIRFL)with86Krionsatroomtemperature.Theionfluencewasvariedfrom5×1010to1×1012cm?2.Additionally,thinaluminumfoilswithdifferentthickness(sometensofmicrometers)wereplacedinfrontofsomesamplestodeceleratetheSHI's.Ionbeamscanningwasusedtoirradiatethewholesamplesurfaceinauniformwayandmaintainednormalincidence.Topreventsampleheatingduringhigh-energyirradiation,thefluxwaskeptconstantbelow1.3×1010cm?2s?1.ThemodificationsofthesampleswereinvestigatedbyXRD.

简介：Lifetimemeasurementsoflow-lyingexcitedstatesin^87Zrhavebeenperformedviaβ-γcoincidences.The127MeV^32SbeamwasdeliveredfromtheSector-FocusingCyclotron(SFC)oftheHeavyIonResearchFacilityinLanzhou(HIRFL).Theparentnuclei^87Nbwereproducedbythereaction58Ni(32S,2p1n),atabeamenergy127MeVthrougha8umAldegrader.A200ug/cm^2layerof58Nievaporatedontoa200ug/cm^2thickcarbonfoilwasemployedasthetarget.Afterevaporationresidueswereseparatedfromtheprojectilebeamsbythegas-filledrecoilseparatorSHANS[1],thenucleiofinterest87Zrcanbeobtainedwithahigherpurityandthenwereimplantedintoa300umsilicondetector.

简介：ThecompressionbehaviourofPd39Ni10Cu30P21bulkmetallicglassisivestigatedatroomtemperatureupto23.5GPausinginsituhighpressureenergydispersivex-raydiffractionwithasynchrotronradiationsource.Pressureinducedstrucuralrelaxationofthebulkmetallicglassisexhibitedwithinthepressurerange.Itisfoundthatbelowabout5GPa,theexistenceofexcessfreevolumecontributestorapidstructuralrelaxation,whichgivesrisetorapidvolumeticchange.Underhigherpressure,furtherrelaxationresultsinstructuralstiffness.

简介：本文通过对2017年全国高考理综（I）卷第21题的若干种解法分析,旨在增强高考复习时分析题目的意识,倡导通过一题多解,发散学生的思维,引导学生去寻求发现巧解、妙解,让学生在比较与讨论中找出最简便的解法和独特的富有新意的解题思路,真正培养学生对多种解题方法的认识.利用一题多解既能让学生复习归纳知识,也能让学生在头脑中建立不同知识之间的联系,完善学生的知识认知结构体系,真正促进学生的综合能力的发展.