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1.
<正> 1.E. A. Bender,数学模型引论,朱尧辰、徐伟宣译,科学普及出版社,1982.2.近藤次郎,数学模型,宫荣章等译,机械工业出版社,1985.3.姜启源,数学模型,高等教育出版社,1987.4.任善强,数学模型,重庆大学出版社,1987.5.M. Braun, C. S. Coleman, D. A. Drew,微分方程模型,朱煜民、周宇虹译,国防科技大学出版社,(本书为W. P. Lucas主编的Modules in Applied Mathematics一书的第一卷),1988.  相似文献   

2.
主要讨论G-凸上的广义向量拟均衡问题,推广W.O ettli,D.Sch l ger,Q.H.A nsari,I.V.K onnov,和J.C.Y ao的一些主要结果.  相似文献   

3.
一、选择题:共12小题,共60分1.sin210°()A.23B.-23C.21D.-212.函数y=|sinx|的一个单调增区间是()A.-π4,-4πB.4π,34πC.π,32πD.32π,2π3.设复数z满足1 z2i=i,则z=()A.-2 iB.-2-iC.2-iD.2 i4.下列四个数中最大的是()A.(ln2)2B.ln(ln2)C.ln2D.ln25675.在△ABC中,已知D是AB边上一点,若AD=2DB,CD=31CA λCB则λ=()A.32B.31C.-31D.-326.不等式xx2--14>的解集是()A.(-2,1)C.(-2,1)∪(2, ∞)B.(2, ∞)D.(-∞,-2)∪(1, ∞)7.已知正三棱柱ABC-A1B1C1的侧棱长与底面边长相等,则AB1与侧面ACC1A1所成角的正弦值等于()A.46B.…  相似文献   

4.
ThisprojectissupportedbytheNationalNaturalScienceFoundationofChinaandDoctoralProgramFoundationofHigherEducation.1.IntroductionLetUI,U2,'bei.i.d.randomvariableswithuniformd.f.ontheinterval(0,l),andforeveryn31,writeUt,,15'5Un,.fortheorderstatisticsofUI,'tUn.SupposethatXI1X2,'arei.i.d.observationsfromanondegenerated.f.F,anddenotebyX.,l5'5X.,.theorderstatisticsofXI,'IX,,'Withoutlossofgenerality,wewillassume0相似文献   

5.
1.IntroductionSupposethatinthelinearregressionmodelK=XIP ei.KarenotcompletelyobserVableandtheObserVationsare(X',Zi,6i),i=l,'',n,wherePandXiarepx1vectors,Zi=adn(K,Wi),6i=I(K5Wi),theresidualei'sarei.i.d.r.v.'swithunknowncommondensityfullctionj(distributionfunctionF)andthe(Wi,Xi)'sarei.i.d.randomvectorsthatareindependentofei's.Fittingthemodelwithcensoreddatahasreceivedconsiderableattentioninthestatistical.literature.TherearetWOmaintrendsinthisbodyofliterature.OnetrendistoeXtendthecompl…  相似文献   

6.
一、选择题:本大题共12小题,共60分.1.化简(12 4i)i2的结果是()A.2 iB.-2 iC.2-iD.-2-i2.li mx→1x3-x2x-1()A.等于0B.等于1C.等于3D.不存在3.若tan4π-α=3,则cotα等于()A.-2B.-12C.12D.24.已知x 33xn展开式中,各项系数的和与其各项二项式系数的和之比为64,则n等于()A.4B.5C.6D.75.若0π3xC.sinx<π42x2D.sinx>π42x26.若集合M={0,1,2},N={(x,y)|x-2y 1≥0,且x-2y-1≤0,x,y∈M},则N中元素的个数为()7.A如.图9,正方B.体6ACC.4D.21的棱长为1,过点A作平面A1BD的垂线,垂足为点…  相似文献   

7.
一、选择题(共44分,每题4分)1.-2的相反数是()A.-12B.21C.2D.-22.下列运算中,正确的是()A.4=2B.2-3=-6C.(ab)2=ab2D.3a 2a=5a23.下列根式中,与3是同类二次根式的是()A.24B.12C.23D.184.下列图形中,不是中心称图形的是()A.圆B.菱形C.矩形D.等边三角形5.据国家环保总局通报,北京市是“十五”水污染防治计划完成最好的城市.预计今年年底,北京污水处理能力可以达到每日1684000吨.将1684000吨用科学记数法表示为()A.1.684×106吨B.1.684×105吨C.0.1684×107吨D.16.84×105吨6.如图,在半径为5的⊙O中,如果弦AB的长为8,那么它的弦心距OC…  相似文献   

8.
一、选择题(本大题共10小题,每小题3分,共30分)1.方程x2-5x=0的根()A.0B.0,5C.5,5D.52.甲乙两人在相同的条件下各射靶10次,他们的环数的方差分别为S2甲=2.4,S2乙=3.2,则射击稳定程序是()A.甲高B.乙高C.两人一样D.不能确定的3.抛物线y=x2-2x 3的对称轴是直线()A.x=-2B.x=2C.x=-1D.x=14.如果α是锐角,且sinα=54,那么cos(90°-α)=()A.54B.43C.53D.515.若关于x的方程x2 2x k=0有实数根,则()A.k<1B.k≤1C.k≤-1D.k≥-16.下列命题中,假命题是()A.两条弧的长度相等,它们是等弧B.等弧所对的圆周角相等C.直径所对的圆周角是直角D.一条弧…  相似文献   

9.
于秀源 《数学学报》1985,28(4):545-556
<正> 代数函数与代数数的某些性质的相似性,引起人们的兴趣.在 B.P.Gill,C.F.Osgood,W.M.Schmidt,S.Uchiyama 及 R.C.Mason 等人的文章中,就研究了关于代数函数的 Thue-Siegel 方程等问题.  相似文献   

10.
1.IntroductionAswellknown,RQI(RayleighQuotientiteration)isapracticalalgorithmforeigen-valueproblemsofsymmetricmatrices.In1974,B.N.ParlettprovedthatthesequencegeneratedbyRQIalwaysconvergestoaneigenvectorforalmostallofinitialvectorsifthematrixinquestionisanormalone.NamelythesetofvectorsinR",forwhichRQIdiverges,hajszeromeasure.Nevertheless,healsopointedouttheconvergelitspeedbeingcubicone[1].In1989,S.BarttsonandJ.SmillieconsideredRQIforsymmetricmatrixagain.Theydiscoveredthatthedynamicsof…  相似文献   

11.
信用传染违约Aalen加性风险模型   总被引:1,自引:0,他引:1  
田军  周勇 《应用数学学报》2012,35(3):408-420
本文考虑了基于加性风险模型的信用风险违约预报模型,不但考虑了宏观因素和公司个体因素,并且通过引入行业因素来刻画公司间可能存在的不同于宏观因素的信用传染效应,由此克服了以往模型对违约相关性的低估.本文在参数加性风险模型下给出极大似然估计及渐近性,提出两种估计方法并比较二者表现,得到最优权估计更加有效.同时本文还考虑了半参数的风险模型,并基于鞅的估计方程得到其估计及渐近性,均得到不错的结果.  相似文献   

12.
Optimal control of nonlinear evolution inclusions   总被引:1,自引:0,他引:1  
In this paper, we study the optimal control of nonlinear evolution inclusions. First, we prove the existence of admissible trajectories and then we show that the set that they form is relatively sequentially compact and in certain cases sequentially compact in an appropriate function space. Then, with the help of a convexity hypothesis and using Cesari's approach, we solve a general Lagrange optimal control problem. After that, we drop the convexity hypothesis and pass to the relaxed system, for which we prove the existence of optimal controls, we show that it has a value equal to that of the original one, and also we prove that the original trajectories are dense in an appropriate topology to the relaxed ones. Finally, we present an example of a nonlinear parabolic optimal control that illustrates the applicability of our results.This research was supported by NSF Grant No. DMS-88-02688.  相似文献   

13.
We consider the estimation of error variance in the analysis of experiments using two level orthogonal arrays. We address the estimator which is the minimum of all the estimators which we obtain by pooling some sums of squares for factorial effects. Under squared error loss, we discuss whether or not this estimator uniformly improves upon the best positive multiple of error sum of squares. We show that when we have two factorial effects, we obtain uniform improvement. However, we show that when we have more than two factorial effects, we cannot necessarily obtain uniform improvement. Further, the above results are applied to the problem of estimating the smallest scale parameter of chi-square distributions.  相似文献   

14.
In this article, we consider a newly modified two-component Camassa–Holm equation. First, we establish the local well-posedness result, then we present a precise blow-up scenario. Afterwards, we derive a new conservation law, by which and the precise blow-up scenario we prove three blow-up results and a blow-up rate estimate result.  相似文献   

15.
We wish to explore all edges of an unknown directed, strongly connected graph. At each point, we have a map of all nodes and edges we have visited, we can recognize these nodes and edges if we see them again, and we know how many unexplored edges emanate from each node we have visited, but we cannot tell where each leads until we traverse it. We wish to minimize the ratio of the total number of edges traversed divided by the optimum number of traversals, had we known the graph. For Eulerian graphs, this ratio cannot be better than two, and two is achievable by a simple algorithm. In contrast, the ratio is unbounded when the deficiency of the graph (the number of edges that have to be added to make it Eulerian) is unbounded. Our main result is an algorithm that achieves a bounded ratio when the deficiency is bounded. © 1999 John Wiley & Sons, Inc. J Graph Theory 32: 265–297, 1999  相似文献   

16.
In this paper we study nonlinear elliptic boundary value problems with monotone and nonmonotone multivalued nonlinearities. First we consider the case of monotone nonlinearities. In the first result we assume that the multivalued nonlinearity is defined on all ℝ. Assuming the existence of an upper and of a lower solution, we prove the existence of a solution between them. Also for a special version of the problem, we prove the existence of extremal solutions in the order interval formed by the upper and lower solutions. Then we drop the requirement that the monotone nonlinearity is defined on all of ℝ. This case is important because it covers variational inequalities. Using the theory of operators of monotone type we show that the problem has a solution. Finally in the last part we consider an eigenvalue problem with a nonmonotone multivalued nonlinearity. Using the critical point theory for nonsmooth locally Lipschitz functionals we prove the existence of at least two nontrivial solutions (multiplicity theorem).  相似文献   

17.
基于跳扩散过程的可转换债券的定价   总被引:2,自引:0,他引:2  
本文标的股票的方程采用跳扩散方程,首先规定一个跳跃的涨跌区间,这样就可以很快的找出跳跃点,我们根据跳跃点将股价聚类,然后把各个类看成是总体中抽取出来的一个样本,我们就可以估计出跳扩散方程中的所有参数.由于我们的标的股票的方程是含跳过程,因此无法找出完全保值的自融资策略,但我们可以根据风险最小化的原理给出可转换债券的价格,最后运用Monte Carlo模拟计算出了南京水运转债在0时刻的价格。  相似文献   

18.
If every subring of an integral domain is atomic, we say that the latter is hereditarily atomic. In this paper, we study hereditarily atomic domains. First, we characterize when certain direct limits of Dedekind domains are Dedekind domains in terms of atomic overrings. Then we use this characterization to determine the fields that are hereditarily atomic. On the other hand, we investigate hereditary atomicity in the context of rings of polynomials and rings of Laurent polynomials, characterizing the fields and rings whose rings of polynomials and rings of Laurent polynomials, respectively, are hereditarily atomic. As a result, we obtain two classes of hereditarily atomic domains that cannot be embedded into any hereditarily atomic field. By contrast, we show that rings of power series are never hereditarily atomic. Finally, we make some progress on the still open question of whether every subring of a hereditarily atomic domain satisfies ACCP.  相似文献   

19.
This article provides an algebraic study of intermediate inquisitive and dependence logics. While these logics are usually investigated using team semantics, here we introduce an alternative algebraic semantics and we prove it is complete for all intermediate inquisitive and dependence logics. To this end, we define inquisitive and dependence algebras and we investigate their model-theoretic properties. We then focus on finite, core-generated, well-connected inquisitive and dependence algebras: we show they witness the validity of formulas true in inquisitive algebras, and of formulas true in well-connected dependence algebras. Finally, we obtain representation theorems for finite, core-generated, well-connected, inquisitive and dependence algebras and we prove some results connecting team and algebraic semantics.  相似文献   

20.
本文首先对IPA算法进行了修正,并证明了修正IPA算法的收敛性,然后将修正后的IPA应用到不等式约束凸优化问题中得到新的内点算法,并与传统的障碍函数法作了比较,从理论上体现了新算法的优势,并给出了其工程解求解法以及收敛性的证明.  相似文献   

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