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1、ArtificialNeuralNetworksAbstract:TheArtificialNeuralNetwork(ANN)isafunctionalimitationofsimplifiedmodelofthebiologicalneuronsandtheirgoalistoconstructuseful‘computers’forreal-worldproblemsandreproduceintelligentdataevaluationtechniqueslikepatternreco
2、gnition,classificationandgeneralizationbyusingsimple,distributedandrobustprocessingunitscalledartificialneurons.Thispaperwillpresentasimpleapplicationoftheartificialneuralnetwork:process,designandperformanceanalysis.1.WorkingprocessofArtificialNeural
3、NetworksAnartificialneuronmodelsthedendritesofabiologicalneuronbyreceivingoneormoreinputs,thenapplyingappropriateweights(positiveornegativemultipliers)tothesignals,andpassestheweightedinputstothesoma.Thesomaorbodyofanartificialneuron,receivestheweigh
4、tedinputsandcomputesasingleoutputsignal(adiscreteorcontinuousfunctionofthesumoftheweightedinputs)byapplyingathresholdortransferfunction(Yoon,1989).Thelastsectionofeachartificialneuronisanalogoustotheaxonofabiologicalneuron,andpassestheoutputsignaltoo
5、neormoresubsequentartificialneuronsortotheoutsideworld.Everynon-trivialartificialneuralnetworkcontainsaninputlayerandanoutputlayer.Mostalsocontainoneormoreintermediateprocessinglayers.TypesofNeuralNetworks:Bothfeed-forwardandrecurrentnetworksareexamp
6、lesofsupervisedlearning.Inunsupervisedlearning,noexternalteacherisrequired.Thesystemself-organizestheinputdata,discoveringforitselftheregularitiesandcollectivepropertiesofthedata.Thesefeed-forwardnetworkshavetheabilitytolearn.Todoso,anartificialneura
7、lnetworkmustlearntoproduceadesiredoutputbymodifyingtheweightsfromitsinputs.Theprocessofhowthisisdoneissimple.2.ProblemsA.9trainingsamples,361testingsamples.B.9trainingsamples,361testingsamples.C.11*11trainingsamples,41*41testingsamples.3.DesigningWei
8、ghtedSumactivationfunctionerrorfunctionStep1:initializetheweightparametersandotherparametersdefaultpoints=50;%%隐含层节点数inputpoints=2;%%输入层节点数outputpoints=2;%%输出层节点数Testerror=zeros(1,100);%每个测试点的误差记录a=zeros(1,inputpoints);%输入层节点值y=zeros(1,outputpoints);