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931.
LIU Zhenrong 《系统科学与复杂性》1992,(4)
In this paper a mathematical model of chemical systems is investigated.We present the conditions for the existence and local stability of the steady statesand the periodic solution of the Hopf type.Specifically,we show by using an ana-lytical method that there may exist two or four Hopf bifurcation points separatedat a finite distance from each other;at the same time,a technique for studying theHopf bifurcation value is given. 相似文献
932.
WANG Jianyu 《系统科学与复杂性》1997,(1)
1.IntroductionBentFunctionsformaveryimportantclassofbooleanfunctionsincryptographybecauseoftheirperfectnonlinearity,buttheyareneitherbalancednorthefirstordercorrelationimmune,andveryfewofthemareknown.In[1],Carlet,C.gavethedefinitionofPartiallyBentFunction… 相似文献
933.
A new DNA algorithm to solve graph coloring problem 总被引:1,自引:0,他引:1
Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R). 相似文献
934.
YIN Chuancun 《系统科学与复杂性》1997,(4)
1.IntroductionLet(xt,y,n)bethestandardBrownianmotioninad,denotebyTthefirsteasttimeofacfromD,whereDisaregulardomaininad.LetpEGKd(generalizedKatoclasses)withIll(D)相似文献
935.
Yuan Zhencai~ Zhang Xuefeng~ Deng Yunqing~ Wu Chengkui~ Cao Ruiling~ Peng Quansheng~ 《中国工程科学》2007,5(1)
1IntroductionThe constructors entering the plateau fromthehinterland,a series of compensation andadaptability and change in its organism will takeplace[1-5],because of the coldinfluence whichisshort of suchabominable environments as oxygen,low pressure,et… 相似文献
936.
TheEvaluationModelofGovernmentIntervention(GI)anditsOptimization¥YANGFenglin;CHENJinxian(SchoolofManagementXi'anJiaotongUnive... 相似文献
937.
Anisotropy and Corotation of Galactic Cosmic Rays 总被引:1,自引:0,他引:1
Based on some billion cosmic ray events collected from to by the Tibet Air Shower Array experiment 《中国科学基金(英文版)》2007,15(2):18-20
Based on some 40 billion cosmic ray events collected from 1997 to 2005 by the Tibet Air Shower Array experiment (a major scientific collaboration between China and Japan) operating at the YangBaJing Cosmic Ray Observatory (90.522 E, 30. 102 N; 4300 m above sea level) near Lhasa in Tibet, a two-dimensiondl cosmic-ray intensity map in the sky was obtained with very high directional granularity and unprecedented precision in intensity at a level of 10-4. 相似文献
938.
LUO Ping 《系统科学与复杂性》1997,(1)
1.IntroductionItiswellknownthattheextrapolationmethodscanimprovetheaccuracyoffiniteelementsolutionandarewellstudiedinmanypapers.Wereferto[1--4]forafundamentalworkonasymptoticerrorexpansionsandextrapolationsandto[5]forasurveyonextrapolationtechniques.Forth… 相似文献
939.
940.
LIU Guizhen 《系统科学与复杂性》1992,(2)
Let T(G)be the tree graph of a simple graph G.It is proved that ifT and T′are two vertices of T(G)such that d_T(G)(T)(?)d_T(G}(T′),then there ared_T(G)(T) internally disjoint paths in T(G) joining T and T′. 相似文献