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292 个结果
  • 简介:Basedontheextendedmappingdeformationmethodandsymboliccomputation,manyexacttravellingwavesolutionsarefoundforthe(3+1)-dimensionalJMequationandthe(3+1)-dimensionalKPequation.Theobtainedsolutionsincludesolitarysolution,periodicwavesolution,rationaltravellingwavesolution,andJacobianandWeierstrassfunctionsolution,etc.

  • 标签: 非线性偏微分方程 JM函数 行进波 精确解
  • 简介:本文介绍了对MJ—l型静电场实验仪的一种改进方法.改进后的仪器能直接记录电位线。

  • 标签: 探针 滑块 模拟静电场
  • 简介:Withthehelpofanextendedmappingapproach,anewtypeofvariableseparationexcitationwiththreearbitraryfunctionsofthe(2+1)-dimensionaldispersivelong-waterwavesystem(DLW)isderived.Basedonthederivedvariableseparationexcitation,abundantnon-propagatingsolitonssuchasdromion,ring,peakon,andcompactonetc.arerevealedbyselectingappropriatefunctionsinthispaper.

  • 标签: 映射展开逼近 局部激发 DLW系统 水波色散 非线性物理模型
  • 简介:TheextendedRiccatimappingapproachisfurtherimprovedbygeneralizedRiccatiequation,andcombineitwithvariableseparationmethod,abundantnewexactcomplexsolutionsforthe(2+1)-dimensionalmodifieddispersivewater-wave(MDWW)systemareobtained.Basedonaderivedperiodicsolitarywavesolutionandarationalsolution,westudyatypeofphenomenonofcomplexwave.

  • 标签: 广义RICCATI方程 系统 水波 色散 复合波 变形
  • 简介:π-/π+ratiowasfoundtobeasensitiveprobetothehigh-densitybehaviorofthesymmetryenergybyusingseveraltransportmodels.However,asshowninFig.1,atbeamenergiesbelowthepionproductionthreshold,theeffectsofin-mediumnucleon-nucleonscatteringcrosssection(whichisstillcontroversial)stronglyaffectthevalueofπ??/π+ratio[1].Itisthusnecessarytodoacomparativestudyoftheeffectsofthein-mediumNNcrosssectionandtheeffectsofthesymmetryenergyonpionproductioninheavy-ioncollisionsatlowerbeamenergies.

  • 标签: NUCLEAR SYMMETRY ENERGY
  • 简介:Basedonthedensity-functionaltheory,thispaperstudiesthegeometricandmagneticpropertiesofTinO(n=1-9)clusters.TheresultinggeometriesshowthattheoxygenatomremainsonthesurfaceofclustersanddoesnotchangethegeometryofTinsignificantly.Thebindingenergy,second-orderenergydifferenceswiththesizeofclustersshowthatTi7Oclusterisendowedwithspecialstability.ThestabilityofTinOclustersisvalidatedbytherecenttime-of-flightmassspectra.ThetotalmagneticmomentsforTinOclusterswithn=1-4,8-9areconstantwith2anddroptozeroatn=5-7.Thelocalmagneticmomentandchargepartitionofeachatom,andthedensityofstatesarediscussed.ThemagneticmomentoftheTinOisclearlydominatedbythelocalized3delectronsofTiatomswhiletheoxygenatomcontributesaverysmallamountofspininTinOclusters.

  • 标签: 钛氧化合物 稳定性 密度函数理论 磁矩
  • 简介:对称一(2+1)维的浅水波浪系统,最新通过使用分析力学的变化原则被构造,在这篇论文被研究。谎言对称和相应减小借助于古典谎言组途径被获得。(1+1)维的排水量当特殊对称参数被选择时,浅水波浪方程能从减小被导出。

  • 标签: 对称性 空间 浅水波 李群 群论
  • 简介:UsingthestandardtruncatedPainlevexpansion,theresidualsymmetryofthe(2+1)-dimensionalmodifieddispersivewater-wavesystemislocalizedintheproperlyprolongedsystemwiththeLiepointsymmetryvector.Somedifferenttransformationinvariancesarederivedbyutilizingtheobtainedsymmetries.ThesymmetriesofthesystemarealsoderivedthroughtheClarkson-Kruskaldirectmethod,andseveraltypesofexplicitreductionsolutionsrelatetothetrigonometricorthehyperbolicfunctionsareobtained.Finally,somespecialsolitonsaredepictedfromoneofthesolutions.

  • 标签: DISPERSIVE water-wave system SYMMETRY reduction EX
  • 简介:Usingafurthermodifiedextendedtanh-functionmethod,richnewfamiliesoftheexactsolutionsforthe(2+1)-dimensionalBroer-Kaup(BK)system,comprisingthenon-travelingwaveandcoefficientfunctions'soliton-likesolutions,singularsoliton-likesolutions,periodicformsolutions,areobtained.

  • 标签: 双曲正切函数 修正展开法 BK系统 精确解 周期孤波
  • 简介:ResourcesonacomputationalGridaregeographicallyistributed,heterogeneousinnature,ownedbydifferentindividualsororganizationswiththeirownschedulingpolicies,havedifferentaccesscostmodelswithdynamicallyvaryingloadsandavailabilityconditions.Thismakertraditionalapproachestoworkloadmanagement,loadbalancingandschedulinginappropriate.Thefirstworkpackage(WP1)oftheEU-fundedDataGridprojectisadddressingtheissueofoptimzingthedistributionofjobsontoGridresourcesbasedonaknowledgeofthestatusandcharacteristicsoftheseresourcesthatisnecessarilyout-of-date(collectedinafiniteamonutoftimeataverylooselycoupledsite).WedescribetheDataGridapproachinintegratingexistingsoftwarecomponents(fromCondor,GGlobus,etc.)tobuildaGridResourceBroker,andtheearlyeffortstodefineaworkableschedulingstrategy.

  • 标签: 软件工具 GRID工具 计算方法
  • 简介:激光极管由于体积小、重量轻、转换效率高、容易实现光纤传输等优点,已经广泛应用于军事、科研、工业等各个领域。由于激光极管是一种具有极高量子效率的器件,微小的电流变化将导致光功率输出的极大变化和器件参数(如波长、噪声性能、模式跳动等)的变化,这些变化直接影响激光器件的安全工作和应用要求。激光点火系统需要激光极管以脉冲方式工作。因此,需要设计出恒流特性稳定、脉宽控制准确、抗干扰能力强,并具有防过冲、反冲和浪涌的保护电路的驱动电源,以保证激光器稳定工作、性能可靠和使用寿命长。

  • 标签: 激光二极管 激光点火系统 电源设计 驱动电源 器件参数 噪声性能
  • 简介:全氘代聚合物泡沫作为一种特殊的低密度、微孔聚合物泡沫,在激光惯性约束聚变(ICF)研究中除了直接用于ICF靶材料,以增加单位靶中热核燃料的密度外,还可用在冷冻靶中以提高液体氘氚的浸润性及分布的均匀性,减小瑞利一泰勒界面不稳定性,以加强中子和分光镜的测量,研究和诊断内爆物理实验等。

  • 标签: 二乙烯基苯 泡沫 氘代 激光惯性约束聚变 微孔聚合物 制备
  • 简介:韩国研究人员发现,经过精心设计的白光发光极管有助于优化个人的生理节律。韩国国民大学JiHyeOh及其同事研究了四组白光LED,其中包括荧光粉转换型红光LED、黄橙光LED、绿光LED和蓝光LED,以及一个长波长粉色镜。他们把这些装置与各种传统形式的照明装置做比较,发现这四组LED设计的照明效率高,

  • 标签: 白光发光二极管 色彩效果 白光LED 视觉 照明装置 红光LED
  • 简介:TogaindeepinsightintotheMorphologicaleffectofNixMg1-xOcatalystsonthereactionofCO2reformingwithmethane,wedesignedandfabricatedthreedifferentspatialstructuralNixMg1-xOcatalysts.TheseNixMg1-xOcatalystswithspecificmodelssuchasrod,sheetandsphere,exhibitedvariousactivityandstabilityinCO2reformingreaction.HereinNixMg1-xOnanorodsdisplayedhighercatalyticactivity,inwhichmethaneconversionwasupto72%andCO2conversionwas64%at670°Cwithaspacevelocityof79,200mL/(gcath),comparedwithnanosheetandnanospherecounterparts.Furthermore,bothcatalystsofNixMg1-xOnanorodandnanosheetshowedahighresistancetowardcokedepositionandsinteringofactivesitesintheprocessofCO2reformingofmethane.

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  • 简介:由考虑(2+1)维的non-isospectral分离零个弯曲方程,(2+1)维的non-isospectralToda格子层次在这篇文章被构造。因而一些减小(2+1)维的Toda格子层次被给。最后,(2+1)联合Toda格子层次的系统的维的integrable通过扩大被获得光谱问题。

  • 标签: 空间 晶格 曲率 方程 计算方法
  • 简介:BasedontheGrammianandPfaffianderivativeformulae,GrammianandPfaffiansolutionsareobtainedfora(3+1)-dimensionalgeneralizedshallowwaterequationintheHirotabilinearform.Moreover,aPfaffianextensionismadefortheequationbymeansofthePfaffianizationprocedure,theWronski-typeandGramm-typePfaffiansolutionsoftheresultingcoupledsystemarepresented.

  • 标签: 浅水方程 广义 双线性形式 过程方程 耦合系统
  • 简介:Thebilinearformofthe(2+1)-dimensionalnon-isospectralAKNSsystemisderived.ItsN-solitonsolutionsareobtainedbyusingtheHirotamethod.Asareduction,a(2+1)-dimensionalnon-isospectralSchrdingerequationanditsN-solitonsolutionsareconstructed.

  • 标签: 孤立子解 Hirota法 等光谱 SCHRODINGER方程