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130 个结果
  • 简介:WepresentthefirststepsofadesignoftheoptimalparametersforafullBraggX-Rayfreeelectronlaser(BX-FEL).AimingtowardsafuturesourceofcoherentX-rayradiation,operatinginthestrongComptonregime,weenvisagethesystemtobetheseedforanadvancedlightsourceorcompactmedicalX-raysource.Herewefocusonthedesignoftheacceleratorparameters:maximumgradient,optimalacceleratedcharge,maximumefficiency,and‘wakecoefficient’,whichrelatestothedeceleratingelectricfieldgeneratedduetothemotionofacharged-lineortrainofcharged-lines.Specifically,wedemonstratethatthemaximumefficiencyhasoptimalvalueandgiventhefluenceofthematerials,themaximumacceleratedchargeinthetrainisconstant.Thesetworesultsmightbeimportantinanyfuturedesign.

  • 标签: BRAGG wake-field COMPTON SCATTERING energy CONVERSION
  • 简介:由于他们的结构上的二金属的nanoparticles(NP)的化学、物理的性质的依赖,他们的结构的特征的基本理解为他们的综合体和宽应用是关键的。在这篇文章,Au-Pd二金属的NP的系统的原子水平的调查被在不同Au/Pd比率和不同尺寸与量修正Sutton陈潜力(Q-SC)使用改进粒子群优化(IPSO)进行。在IPSO,模仿的退火被介绍进古典粒子群优化(PSO)改进有效性和可靠性。另外,结构的稳定性和结构的特征上的起始的结构,粒子尺寸和作文的影响也被学习。模拟结果表明起始的结构在稳定的结构上有小效果,但是极大地影响收敛的率,并且起始的结构清楚地是的混合的集中率快核心壳和阶段比那些组织。我们发现Au-PdNP比较喜欢结构与在外部层Au富有当时在内部的Pd富有。特别,当Au/Pd比率是6:4时,nanoparticle(NP)的结构介绍标准化Pd核心Au壳结构。

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  • 简介:由Synechcoccus在Ni的简历累积上影响因素在这篇论文被学习。当到干燥重量集中ofSynechcoccus的Ni的集体比率是16-18%时,简历累积在附近是在水的solution.Bioaccumulation数量的80min的Ni的使平衡时间到达了最大值。Bioaccumulation数量与增加pH增加了。最佳pHwas9-10和更高的pH导致了Ni的降水(哦)_2。Bioaccumulation数量被在35℃到达他们的optima的温度和轻紧张也影响,无生命的水藻的3000Ixrespectively.Bioaccumulation比生活水藻的大。

  • 标签: 生物积累 矿山排水污染 环境保护
  • 简介:Inthispaperwepresentanextensionofthetopologyoptimizationmethodtoincludeuncertaintiesdur-ingthefabricationofmacro,microandnanostructures.Morespecifically,weconsiderdevicesthataremanufacturedusingprocesseswhichmayresultin(uniformly)toothin(eroded)ortoothick(dilated)structurescomparedtotheintendedtopology.ExamplesareMEMSdevicesmanufacturedusingetchingprocesses,nano-devicesmanufacturedusinge-beamlithographyorlasermicro-machiningandmacrostructuresmanufacturedusingmillingprocesses.Inthesuggestedrobusttopologyoptimizationapproach,under-andover-etchingismodelledbyimageprocessing-based'erode'and'dilate'operatorsandtheoptimizationproblemisfor-mulatedasaworstcasedesignproblem.Applicationsofthemethodtothedesignofmacrostructuresforminimumcomplianceandmicrocompliantmechanismsshowthatthemethodprovidesmanufacturingtolerantdesignswithlittledecreaseinperformance.Asapositivesideeffecttherobustdesignformulationalsoeliminatesthelongstandingprob-lemofone-nodeconnectedhingesincompliantmechanismdesignusingtopologyoptimization.

  • 标签: 拓扑优化设计 制造过程 容错 MEMS器件 宏观结构 蚀刻工艺
  • 简介:Inthispaper,LCPisconvertedtoanequivalentnonsmoothnonlinearequationsystemH(x,y)=0byusingthefamousNCPfunction-Fischer-Burmeisterfunction.NotethatsomeequationsinH(x,y)=0arenonsmoothandnonlinearhencedifficulttosolvewhiletheothersarelinearhenceeasytosolve.ThenwefurtherconvertthenonlinearequationsystemH(x,y)=0toanoptimizationproblemwithlinearequalityconstraints.AfterthatwestudytheconditionsunderwhichtheK-TpointsoftheoptimizationproblemarethesolutionsoftheoriginalLCPandproposeamethodtosolvetheoptimizationproblem.Inthisalgorithm,thesearchdirectionisobtainedbysolvingastrictconvexprogrammingateachiterativepoint,However,ouralgorithmisessentiallydifferentfromtraditionalSQPmethod.Theglobalconvergenceofthemethodisprovedundermildconditions.Inaddition,wecanprovethatthealgorithmisconvergentsuperlinearlyundertheconditions:MisP0matrixandthelimitpointisastrictcomplementaritysolutionofLCP.Preliminarynumericalexperimentsarereportedwiththismethod.

  • 标签: 最优化 非线性方程 函数 数值逼近
  • 简介:Inordertosolvetheconstrainedglobaloptimizationproblem,weusepenaltyfunctionsnotonlyonconstraintsbutalsoonobjectivefunction.Thenwithintheframeworkofintervalanalysis,anintervalBranch-and-Boundalgorithmisgiven,whichdoesnotneedtosolveasequenceofunconstrainedproblems.Globalconvergenceisproved.Numericalexamplesshowthatthisalgorithmisefficient.

  • 标签: CONSTRAINED golbal OPTIMIZATION INTERVAL analysis penally
  • 简介:多重数据(SIMD)指令经常是的单个说明在现代媒介处理器实现了。尽管SIMD指令在多媒体应用程序是有用的,大多数编译器没为SIMD指令有好支持。这篇论文为媒介处理器集中于SIMD指令产生。我们在场集成于一个retargetableC编译器的一条有效代码优化途径。SIMD指令被发现产生;在程序联合一样的操作。UltraSPARC力指令集的试验性的结果证明直到2.639的一个加速因素被获得。

  • 标签: 计算机软件 编译程序 单指令多倍数据 处理器
  • 简介:Inthispapertheeffectsofthecondenserdesignparameters(suchasturbineinletcondition.turbinepowerandcondenserpressure)onheattransferarea,coolingwaterflow-rate.condensercostandspecificenergygenerationcostarestudiedforsurfacetypecondenser.Theresultsaregiveninthetextandalsoshownasdiagrams.

  • 标签: 冷凝器 能量消耗 最优化 蒸汽轮机 蒸汽动力装置
  • 简介:Experimentshaveshownthattheionenergyobtainedbylaser–ionaccelerationcanbeoptimizedbychoosingeithertheappropriatepulsedurationortheappropriatetargetthickness.WedemonstratethatthisbehaviorcanbedescribedeitherbythetargetnormalsheathaccelerationmodelofSchreiberetal.orbytheradiationpressureaccelerationmodelofBulanovandcoworkers.Thestartingpointofourconsiderationsisthattheessentialpropertyofalasersystemforionaccelerationisitspulseenergyandnotitsintensity.Maybesurprisinglyweshowthathigherionenergiescanbereachedwithreducedintensities.

  • 标签: laser–ion ACCELERATION RELATIVISTIC LASER PLASMA INTERACTION
  • 简介:AbstractThepurposeofthearticleistoformulate,underthel_∞riskmeasure,amodelofportfolioselectionwithtransactioncostsandtheninvestigatetheoptimalstrategywithintheproposed.Thecharacterizationofaoptimalstrategyandtheefficientalgorithmforfindingtheoptimalstrategyaregiven.

  • 标签: TRANSACTION COST PORTFOLIO OPTIMIZATION MODEL ALGORITHM
  • 简介:Theset-valuedoptimizationproblemwithconstraintsisconsideredinthesenseofsuperefficiencyinlocallyconvexlineartopologicalspaces.Undertheassumptionofic-cone-convexlikeness,byapplyingtheseperationtheorem,Kuhn-Tucker's,Lagrange'sandsaddlepointsoptimalityconditions,thenecessaryconditionsareobtainedfortheset-valuedoptimizationproblemtoattainitssupereffcientsolutions.Also,thesufficientconditionsforKuhn-Tucker's,Lagrange'sandsaddlepointsoptimalityconditionsarederived.

  • 标签: 集值优化 最优性条件 线性拓扑空间 优化问题 拉格朗日 分离定理
  • 简介:Thispaperpresentsnonmonotonicquasi-Newtonalgorithmsviatwopre-conditionalcurvilinearpaths,thepreconditionalmodifiedgradientpathandtheprecon-ditionaloptimalpath,forunconstrainedoptimizationproblem.WeemploythestableBunch-Parlettfactorizationmethodtoformtwocurvilinearpathsveryeasily.Thenonmonotonecriterionisusedtospeeduptheconvergenceprogressinthecontoursofobjectivefunctionwithlargecurvature.Theoreticalanalysesaregivenwhichprovethattheproposedalgorithmsaregloballyconvergentandhavealocalsuperlinearcon-vergencerateundersomereasonableconditions.Theresultsofnumericalexperimentsarereportedtoshowtheeffectivenessoftheproposedalgorithms.

  • 标签: 无约束最优化 非单调 曲线轨迹算法 最佳途径 因子分解法
  • 简介:Thispaperdealswithamethodologyforsinglegatelocationoptimizationforplasticinjectionmold.Theobjectiveofthegateoptimizationistominimizethewarpageofinjectionmoldedparts,becausewarpageisacrucialqualityissueformostinjectionmoldedpartswhileitisinfluencedgreatlybythegatelocation.Featurewarpageisdefinedastheratioofmaximumdisplacementonthefeaturesurfacetotheprojectedlengthofthefeaturesurfacetodescribepartwarpage.Theoptimizationiscombinedwiththenumericalsimulationtechnologytofindtheoptimalgatelocation,inwhichthesimulatedannealingalgorithmisusedtosearchfortheoptimum.Finally,anexampleisdiscussedinthepaperanditcanbeconcludedthattheproposedmethodiseffective.

  • 标签: 注射模拟 最优化 塑料材料 成型加工
  • 简介:Inthispaper,weextendanovelunconstrainedmultiobjectiveoptimizationalgorithm,so-calledmultiobjectiveextremaloptimization(MOEO),tosolvetheconstrainedmultiobjectiveoptimizationproblems(MOPs).Theproposedapproachisvalidatedbythreeconstrainedbenchmarkproblemsandsuccessfullyappliedtohandlingthreemultiobjectiveengineeringdesignproblemsreportedinliterature.Simulationresultsindicatethattheproposedapproachishighlycompetitivewiththreestate-of-the-artmultiobjectiveevolutionaryalgorithms,i.e.,NSGA-II,SPEA2andPAES.ThusMOEOcanbeconsideredagoodalternativetosolveconstrainedmultiobjectiveoptimizationproblems.

  • 标签: 最佳化 人工智能 工程设计 极值曲线