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简介：InthisnoteasimpleproofofthefamousFermat-Torricelliproblemisgiven.Fortheverticesofagiventriangle,FermatasksforafourthpointsuchthatthesumofitsEuclideandistancestothethreegivenpointsisminimized.ManyauthorspresentgeometricapproachestotheFermat-Torricelliproblem.Wesolvetheproblembyanalyticandgeometricalmethodandextendittothesphere.wealsocharacterizethemedianpointPonthegeneralregularsurface.

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简介：IntheBigBangtheory,primordialnucleosynthesiswasfinishedduringfirsthalfhouroftheuniverse’sexistence.Thisprocessyieldedthemainlightelementsincludinghydrogen,deuterium,heliumandlithium.Thetheoreticalpredictionsmatchverywelltheobserveddeuteriumandheliumabundance,butthe7Liabundanceisoverpredictedbyafactorathree[1].Thisinconsistencyiscalled“cosmologicallithiumproblem”.Inthepastdecade,manyattemptstosolvethisproblemusingconventionalastrophysicsandnuclearphysicsfailed.Recently,weproposedanewsolutiontolithiumproblembyintroducingnon-extensivestatisticsintoBigBangnucleosynthesis[2].

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简介：Inthispaper,byusingtheGuo-Krasnoselskii'sfixed-pointtheorem,weestablishtheexistenceandmultiplicityofpositivesolutionsforafourth-ordernonlineareigenvalueproblem.Thecorrespondingexamplesarealsoincludedtodemonstratetheresultsweobtained.

简介：Theplatformschedulingprobleminbattlefieldisoneoftheimportantproblemsinmilitaryoperationalresearch.Itneedstominimizemissioncompletingtimeandmeanwhilemaximizethemissioncompletingaccuracywithalimitednumberofplatforms.Thoughthetraditionalcertainmodelsobtainsomegoodresults,uncertainmodelisstillneededtobeintroducedsincethebattlefieldenvironmentiscomplexandunstable.Anuncertainmodelisprposedfortheplatformschedulingproblem.Relatedparametersinthismodelaresettobefuzzyorstochastic.Duetotheinherentdisadvantageofthesolvingmethodsfortraditionalmodels,anewmethodisproposedtosolvetheuncertainmodel.Finally,thepracticabilityandavailabilityoftheproposedmethodaredemonstratedwithacaseofjointcampaign.

简介：Thepurposeofthispaperistointroduceasplitgeneralizedmixedequilibriumproblem(SGMEP)andconsidersomeiterativesequencestofindasolutionofthegeneralizedmixedequilibriumproblemsuchthatitsimageunderagivenboundedlinearoperatorisasolutionofanothergeneralizedmixedequilibriumproblem.Weobtainsomeweakandstrongconvergencetheorems.

简介：perspective-three-point(P3P)的一个完全的答案分类问题被使用Gr给?bner基础方法。P3P问题推出的多项式系统的解决方案空格的结构能被计算全面Gr获得?bner系统。与概括判别式的性质结合定序，作者给明确的条件决定P3P问题的不同真实积极答案的数字。几个例子被提供说明建议条件的有效性。

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简介：Byapplyingiterativetechnique,weobtaintheexistenceofpositivesolutionsforasingularRiemann-Stieltjesintegralboundaryvalueprobleminthecasethatf(t,u)isnon-increasingrespecttou.

简介：Coalitional技巧比赛(CSG)是在每个代理人有被要求完成许多任务的一套技巧的不明确的环境的合作的一个简单模型，每项任务要求一套技巧被完成，但是每技巧是很难的被确定并且能仅仅是表示的品质上。因此远，包围CSG的许多计算问题被学习了。就我们的知识而言，作为CSG的一个中央问题，然而，联盟结构产生问题(CSGP)是极其挑战性的并且很好没被解决。到这个目的，二个不同计算智力算法此处被评估：二进制粒子群优化(BPSO)和二进制微分进化(BDE)。特别地，我们与二维的二进制代码编码开发二个随机的搜索算法并且相应为单个修理启发式。在那以后，我们讨论一些基本性质求婚启发式。最后，我们为在CSG解决CSGP把改进BPSO和BDE与最先进的算法作比较。试验性的结果证明我们的算法能与存在途径在最佳的答案附近发现一样，但是花极其短的时间，特别在大问题尺寸下面。

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简介：在这份报纸，我们由输出反馈控制学习分离线性时间延期系统的输出规定问题。我们为连续线性时间延期系统的产量规定问题建立了一些结果平行到那些。

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简介：Thispaperdiscussesastatisticalsecond-ordertwo-scale(SSOTS)analysisandcomputationforaheatconductionproblemwitharadiationboundaryconditioninrandomporousmaterials.Firstly,themicroscopicconfigurationforthestructurewithrandomdistributionisbrieflycharacterized.Secondly,theSSOTSformulaeforcomputingtheheattransferproblemarederivedsuccessivelybymeansoftheconstructionwayforeachcell.Then,thestatisticalpredictionalgorithmbasedontheproposedtwo-scalemodelisdescribedindetail.Finally,somenumericalexperimentsareproposed,whichshowthattheSSOTSmethoddevelopedinthispaperiseffectiveforpredictingtheheattransferperformanceofporousmaterialsanddemonstratingitssignificantapplicationsinactualengineeringcomputation.

简介：Concerningthespecificdemandonsolvingthelong-termconjugateheattransfer(CHT)problem,anewalgorithmoftheglobaltightly-coupledtransientheattransferbasedonthequasi-steadyflowfieldisfurtherputforward.Comparedtothetraditionalloosely-coupledalgorithm,thecomputationalefficiencyisfurtherimprovedwiththegreatlyreducedupdatefrequencyoftheflowfield,andmoreovertheupdatestepoftheflowfieldcanbereasonablydeterminedbyusingtheengineeringempiricalformulaoftheNusseltnumberbasedonthechangesoftheinletandoutletboundaryconditions.Takingaductheatedbyinnerforcedairflowheatingprocessasanexample,thecomparingresultstothetightly-coupledtransientcalculationbyFluentsoftwareshowsthatthenewalgorithmcansignificantlyimprovethecomputationalefficiencywithareasonableaccuracyonthetransienttemperaturedistribution,suchasthecomputingtimeisreducedto22.8%and40%whiletheductwalltemperaturedeviationare7%and5%respectivelyusingtwoflowupdatetimestepof100sand50sonthevariableinlet-flowrateconditions.

简介：摘要目的探究以问题为基础的教学法（Problem-BasedLearning，PBL）在普外科实习生带教中的应用效果。方法以80名在我院普外科实习的实习生作为研究对象（属于2013年9月-2016年9月期间），随机分成2组，40名/组。对照组采取传统教学法，观察组实施PBL教学法。将两组的理论知识测试成绩、综合能力考核成绩以及问卷指标评分进行对比。结果观察组的上述各项成绩、评分均高于对照组（p＜0.05）。结论PBL教学法在普外科实习生带教中的应用效果较好。