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1.
复杂系统的演化过程,n(n-1)律,自聚集   总被引:3,自引:2,他引:1  
研究一类复杂系统的演化过程,给出一个网络模型,由此导出f(n)=n(n-1),用以在某种程度上定性地描写演化过程中聚集与功能变化的规律。这里n表示agents的聚集数量。熟知的关系式1+1>2是n=2时的特例。当n为小数时,n的增减对系统整体功能的影响显著,此情况将称为“小n机制”。当n充分大时,系统的整体功能将有大跃升,并可用n2度量,称此为“n2效应”。一般情况下,n(n-1)描写聚集-相互作用-功能跃升的模式,用此模式可对不同领域的演化过程作某种解释。  相似文献   

2.
ANALYSISOFBOUNDARYSHAPEOFSOLUTIONSOFNONLINEARPERTURBATIONPROBLEM¥HECheng;ZHANGWeitao(InstituteofSystemsScience,AcademiaSinica...  相似文献   

3.
ThisresearchissupportedbythePostdoctoralGrantofChina.1.IntroductionLetW(t)for05t相似文献   

4.
对一种改进层次分析法误导的理论分析   总被引:4,自引:2,他引:2  
揭示了基于最优传递矩而建立的改进层次分析法产生误导的原因,从理论上否定了该法的一些错误论断。  相似文献   

5.
CONVERGENCYOFTHEMAXIMUMOFPERIODOGRAM¥HEShuyuan(DepartmentofProbabilityandStatistics,PekingUniversity,Beijing100871,China)Abst...  相似文献   

6.
In this paper,admissibility and inadmissibility results of simultaneous estimation oflosses of multivariate normal mean estimators are given.Admissible estimators for losses ofusual estimators of multivariate gamma parameters,multivariate binomial parameters andPoisson parameters are obtained respectively.  相似文献   

7.
By use of maximum principle and auxiliary function method, the paper dis-cusses the blow-up sets of the solutions of the ignition model in two cases. It is obtained that the solutions blow up in single point in nonsymmetric case and that the solutions blow up totally or at a couple of points in symmetric case.  相似文献   

8.
APROPERTYOFPRODUCTSOFNEWGENERALIZEDFUNCTIONSLIYaqing(InstituteofSystemsScience,AcademiaSinica,Beijing100080,China)APROPERTYOF...  相似文献   

9.
Todeterminethesignofdivergenceatcriticalpointsisanimportantstepininvestigatingthestabilityofseparatrixloopsandthatoflimitcyclesgeneratedfromsuchloops(see[1--3]).JiangI4]hassolvedthisproblemforthequadraticsystemoftype(II)andaspecialboundedsystem.Thispaperwillcompletelysolvethisproblemforthegeneralcase.Themethodusedhereissimplerthanthatin[4].Considerthefollowingquadraticsystemoftype(ill):x=--y 6x lxa mad y',gi~x(l ax by),(1)whereb/0.Weconsiderthecasea/0,andwithoutlossofgenerality,wemadassumea<…  相似文献   

10.
ON A CLASS OF WEIGHT HIERARCHIES OFTERNARY LINEAR CODES OF DIMENSION 4   总被引:3,自引:0,他引:3  
The possible weight hierarchies of ternary codes of dimension 4 satisfying thealmost chain condition are completely determined in this paper.  相似文献   

11.
本文以无源LCF、有源RCF和有源SCF为主线,介绍了滤波器的发展过程、概况、设计方法及特点,讨论了滤波器的演变机理,并着重阐述了无源LCF到有源RCF,和有源RCF到有源SCF的两次重大飞跃,以及无源LCF到有源SCF的直接过渡,还展望了滤波器发展的前景。  相似文献   

12.
In this paper we prove that the distributions of their sojourn time and hitting time at one special state for random walks which are allowed to be finite or infinite and Markov chains on star-graphs with discrete time can uniquely determine the probability distribution of the whole chains. This result also suggests a new statistical method for Markov chains.  相似文献   

13.
Let F be a field and let resA=rank(A-I) for any A in GLnF.We prove that every matrix in SLnF is a product of at most [resA/2] 2 commutators of reflections for n≥2 except for n=2 and F=F2.  相似文献   

14.
1.IntroductionLetXI,X2,''tX.beani.i.d.randomsamplewithcommondistributionfunction(c.d.f.)F(unknown),andFibetheempiricaldistributionfunction(e.d.f.)basedonthesample.ConsiderthefollowingfunctionalofFwhereF--'(t)ginf{x:F(x)2t}istheinversefunctionofF(inversef…  相似文献   

15.
层次分析积因子方法的保序性   总被引:6,自引:0,他引:6  
在应用传统的层次分析方法时,不论采用相对测量还是绝对测量,都存在逆序现象。而产生逆育现象的根源是决策方案集的封闭性及反映决策者主观认识的判断方法对客观存在的决策方案集的严重依赖性。文章介绍了一种保存的层次分析方法-积因子法,证明了在一定的条件下,积因子法是唯一可选用的保序方法。  相似文献   

16.
ESTIMATION OF A KIND OF JUMP REGRESSION FUNCTION   总被引:1,自引:0,他引:1  
Research on jump regression func(?)ons has not been adequate yet According to theinformation about the number of jumps,their positions and jump magnitudes,jump regressionfunctions can be classified into eight types.This paper deals especially with the secondjump regression function.First of all,a concept of trimmed spline estimate is proposed andwith it an L~2-consistent estimate of the smoothing part of the jump regression function isobtained.This along with the L~2-consistent estimate of jump magnitude constitutes an estimateof the second jump regression function.This paper discusses also the case that the jumppositions have some indeterminacy.A new criterion is suggested and its unique solutionderived.In the end,a few numerical results are given.  相似文献   

17.
1. PerfaceIn paper [l], we have established the partial differential equation based on assets develop-mental process. In this paper we will consider the kind of distributed parameter system. Hence,we study the solution of the following problem (K):where a represents the age of productive assets, t represellts time, K(a, t) is the age--distributiondensity function of the productive assets at time t. p(a) is relative depreciation rate of assets. ris the accumulation rate of assets, A(t) means t…  相似文献   

18.
STRONGCONSISTENCYOFM-ESTIMATESOFMULTIPLEREGRESSIONCOEFFICIENTSCHENXiru(GraduateSchooloftheChineseAcademyofSciences,Beijing100...  相似文献   

19.
1.IntroductionConsideringthefollowingsystemoflinearequationsAx~b(l.1)whereAisannxnM-matrix,bisanndimensionalvectorandbeRang(A).Theresearchonthesolutionofequation(1.1)isveryimportantinLeontiefmodelofinput-outputanalysis(see[1,2]).G.St..k.ma[Zjstudiestheabo…  相似文献   

20.
In this paper, we study the problem on the fixed points of the lth power of linear differential polynomials generated by second order linear differential equations. Because of the control of differential equation, we can obtain some precise estimate of their fixed points.  相似文献   

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