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31.
1.INTRODUCTIONThealgorithmforconstrainedoptimizationincomplexsystemscanbedividedintotwoclasses:exactandheuristicmethods.Theexactmethods,whicharepartlysummarizedbyTitanetal.[1],havecomputationalrequiremeatsthatgrowexponentiajlywiththesizeoftheproblem.AlthoughheuristicmethodshavemodestcomputationalrequirementsandareeasytoAnplemellt,theyaregenerallyforredundancyallocation[2-4].2.S~EMENTOFProBLEM2.1NotationN:nUmberofcomponents;M:numberofconstraints;Rs:systemreliability;Rj:thereliabili… 相似文献
32.
1.INTRODUCTION2-statesystemreliabilityoftenassumesthatthesystemisrepresentedbyaprobabilisticgraphG=(V,E),withasetV~{yi,v2,'',}ofvenicesandasetE~{el,e2,'',}ofedges(orlinks,branches)containedinit.Thesystemisfunctioningifthereexistsapathfromtheinputnodetotheoutputnode.Thusthereliabilityisconsideredwithamatterofconnectivityonlyandthereliabilityanalysishasbeenprimarilyconcernedwiththeenumerationofpathesorcutsinthereferences[1-4].Butinmanyphysicalsystemsuchaspowertransmissionsystems,oilorwat… 相似文献
33.
Rong Ximin 《系统工程与电子技术(英文版)》1999,(4)
1.INTRODUCTIONInsurancepricingisaneternalthemeinthestudyofinsurance.Whenwedesignainsuranceproduct,wemusttogiveapricefortheproductinordertoselltheproductininsurancemarkets.Whatiscalledinsurancepricingisactuallytomakeinsurancepremiumofinsuranceproduct.Reasonablepricingofinsuranceproductisofutmostimportancefortheexistenceanddevelopmentofinsurancecompany.Ifpremiumismadetoohigh-priced,althoughinsurancecompanycanobtainhighprofitofunderweightingadcanheightencapacityofinsurancecompanyinpaymentofd… 相似文献
34.
Mallam Zaji Bunuq 《系统科学与系统工程学报(英文版)》1999,(1)
1IntroductionThedecisionmakingprocessinWaterResourcesPlanningandMallagement(WRPM)isapublicplanningprocessandtheoptimumsolutionmustbeacceptedbydecisionmakerswhoinawayrepresentthegeneralPublic(Miloradov,M.etal.,1990).WRPMwithinaMulticriteriaAnalysis(MA)isacomplexanddynamoicprocessinwhichtwodecisionlevelsmaybedistinguished.Theupperleveldefinesthegoals,identifiesthecriteriaandchoosesthefinaloptimumsolution.Thesecondlevelistheengineeringlevelofatechnicalnature;itdefinesalternativesandpoin… 相似文献
35.
1IntroductionArrow'sproofforarrow'sgeneralpossibilitytheorem(GPT)standsontheconditionthatsocialchoiceisdefinedoverailpairsofalternativesl'l,whereas,inmosteconomicproblems,thesetoffeasiblealternativescontainsmorethantwoelements.IthasbeensuspectedthattherootoftheaggregationproblemsencounteredinthetheoryofsocialchoicedoesnotlieinthisspecialaspectofArrow'sframework.Thismotivatesthesearchfornonbinaryimpossibilitytheoremsl2].Inadelicatepaper,GretherandPlotthaveshownthatArrow'sGPTholdswhenailfini… 相似文献
36.
YU Xijun 《系统科学与复杂性》1999,(4)
1.IntroductionItiswellknowthattheconvection-dictionproblemsareakindofveryimportalprob-lems,particularlylthenonlinearconvection-diffusionproblexns.Inthepaper[1],asinglestepcharacteristicflutedmerencemethodisgivenforsolvingtwcadimensionalnonlinearconvection-dilhaionproblemswiththeconvectivecoefficientsdominating.HereweshallgiveamultistepcharactersticamrencemethodbasedonthelinearandquadraticinterpolationsforsolvingtwcadAnensionalnonlinearconvection-~ionproblemsinordertoincreasetheaccuracyofapprot… 相似文献
37.
<正> This paper shows how the so called von Karman model can be obtained as a singular limitof a modified Mindlin-Timoshenko system when the modulus of elasticity in shear k tends to infinity,provided a regularizing term through a fourth order dispersive operator is added.Introducing dampingmechanisms,the authors also show that the energy of solutions for this modified Mindlin-Timoshenkosystem decays exponentially,uniformly with respect to the parameter k.As k→∞,the authors obtainthe damped von Karman model with associated energy exponentially decaying to zero as well. 相似文献
38.
Lijie Zhang Jianguo Huang Yong Jin Yunshan Hou Min Jiang Qunfei Zhang .College of Marine Northwestern Polytechnical University Xi’an P.R.China .Yichang Testing Technique Research Institute Yichang 《系统工程与电子技术(英文版)》2010,21(2):186-190
A new monostatic army system taking advantage of diverse waveforms to improve the performance of underwater target localization is proposed.Unlike the coherent signals between different elements in common active array,the transmitted signals from different elements here are spatially orthogonal waveforms which allow for array processing in the transit mode and result in an extension of array aperture.The mathematical derivation of Capon estimator for this sonar system is described in detail.And the performance of this orthogonal-waveform based sonar is analyzed and compared with that of its phased-array counterpart by water tank experiments.Experimental results show that this sonar system could achieve 12 dB-15 dB additional array gain over its phased-array counterpart,which means a doubling of maximum detection range.Moreover,the angular resolution is significantly improved at lower SNR. 相似文献
39.
Red Qingsheng 《系统工程与电子技术(英文版)》2000,11(3)
1. INTSODUCTIONThe common illteger programming (lP) is a mathematical model which is designed to find aset of non-negative variables to medmize (or minimize) a nonlinear objective function whilesatisfying a set of constraints under integer restrictions of variables. An lP model with somevariables reqllired to be real is a mixed integer programming (MIP).The history of solving lP/MIP problems is not very old. According to reference [1], ageneral method for solvillg such problems may not… 相似文献
40.
Family change, when adults depart or arrive around children, raises policy issues. Its measurement depends upon the evidence collected and from whom. This paper compares British children's histories obtained from fathers and mothers. The evidence, on one birth cohort of parents, comes from two sources: the National Child Development Study and the ONS Longitudinal Study. The resulting account of family change is not substantially different between parents. There is some under-reporting of children not living with their fathers. This is due to under-reporting by those included in the studies and to under-representation in them of absent fathers and lone parents. 相似文献