首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 359 毫秒
1.
本文建立了外环轴水平放置的重力对称陀螺仪的运动方程.将非自由陀螺仪转子的质心位置作为扰动,利用Melnikov方法和KAM理论研究了陀螺仪的运动,研究结果表明:在 螺仪转子的质心与支架中心不重合且充分接近时,或 螺仪能量充分大时,陀螺仪运动的Poincare映射既出现Smale马蹄意义下的混沌,又存在KAM不变环面和不变闭曲线。  相似文献   

2.
20 0 0年 1 0月号问题解答(解答由问题提供人给出 )1 2 76 设I为△ABC的内心 ,K、L、M分别为△ABC的内切圆在BC ,CA ,AB上的切点 .过B且与MK平行的直线分别与直线LM及LK交于R及S ,点J在BI上 ,试证明 :∠RJS是锐角 ,当且仅当BJ >12 (AB BC-AC) .(山东枣庄市立新学校 孔令恩  2 771 0 2 )证明 如图所示 ,IB⊥MKRS∥MK IB ⊥RS∠ABI=∠CBI ∠RBM =∠SBK∠RMB =∠AML =90°- A2∠BSK =∠MKL =90°- A2 ∠RMB=∠BSK △RBM ∽△SBK BRBK …  相似文献   

3.
题目 设I为△ABC的内心,K、L、M分别为△ABC的内切圆在BC、CA、AB上的切点,已知通过点B与MK平行的直线分别与直线LM及LK交于R、S两点,求证∠RIS为锐角.证明 记△ABC的内切圆半径为r,∵ RS∥MK且△MKL为切点三角形,故 ∠RSK=∠MKL=∠LMA,∴ S、L、M、B四点共圆.故 RB·RS=RM·RL.但R是圆I外一点,RM·RL=RI2-r2,∴  RB·RS=RI2-r2(1)同理可知 SB·SR=SI2-r2(2)由(1)、(2)有RI2+SI2-2r2=RS…  相似文献   

4.
第一天大田 ,2 0 0 0年 7月 19日时间 :4小时 30分每题 7分  问题 1 圆Γ1 和圆Γ2 相交于点M和N .设l是圆Γ1 和Γ2 的两条公切线中距离M较近的那条公切线 .l与圆Γ1 相切于点A ,与圆Γ2 相切于点B .设经过点M且与l平行的直线与圆Γ1 还相交于点C ,与圆Γ2 还相交于点D .直线CA和DB相交于点E ;直线AN和CD相交于点P ;直线BN和CD相交于点Q .证明 EP =EQ .解答 令K为MN和AB的交点 .根据圆幂定理 ,AK2 =KN·KM =BK2 ,换言之K是AB的中点 .因为PQ∥AB ,所以M是PQ的中点 .故只需证明E…  相似文献   

5.
定义了一种三角域上Meyer-K[AKoD]nig-Zeller算子,并研究其在C度量下的逼近性质。  相似文献   

6.
三角域上Meyer-K?nig-Zeller算子   总被引:5,自引:0,他引:5  
定义了一种三角域上Meyer-K[AKo‥D]nig-Zeller算子,并研究其在C度量下的逼近性质。  相似文献   

7.
1引言格子Boltzmann方法(LBM)是近几年发展起来的一种模拟复杂系统的新方法[1][2][3]这种方法已经在流体力学各领域得到应用.最近,许多研究工作集中于用LBM模型计算可压缩流体流动.Alexander和Chen等[4]提出了可以计算激波的等温模型,模型中的音速是可以选择的.Qian和Orszag[5]分析了LBGK模型在可压缩区域内的非线性偏差,给出了激波结构的LBM结果.Qian和Orszag[6]也计算了弱可压缩的高Re数问题,并用于计算Kol-mogorov流.Ancona[…  相似文献   

8.
对有限型李代数g(A),相应于每个根a的反射ra均在g(A)的Weyl群W中,当g(A)为可对称化的不定型Kac-Moody代数时,若a为一虚根且(a,a)〈0,则亦可定义反射ra,并有ra∈-W或ra是-W中元与一个图自同构之积,本文给出了一类秩为3的广义Kac-Moody代数的虚根系,然后讨论了一类特殊的广义Kac-Moody代数的虚根决定的反射与Weyl群之间的关系。  相似文献   

9.
Reliability bounds in DFRA class with known mean and variance   总被引:1,自引:0,他引:1  
RELIABILITYBOUNDSINDFRACLASSWITHKNOWNMEAN AND VARIANCECHENGKAN(程侃)(InstituteofAppliedMathematics,theChineseAcademyofScience,B...  相似文献   

10.
蒋美跃  裴明亮 《数学进展》1994,23(2):97-114
本文介绍Aubry-Mather理论近年来的发展情况。文章讨论了该理论与KAM理论、保面积映射不动点理论的联系,简单地介绍了它的一些推广。作为该理论的应用,对平面Hamil-ton系统Mather集的存在性给出了一些结果。  相似文献   

11.
As early as in 1990, Professor Sun Yongsheng, suggested his students at Beijing Normal University to consider research problems on the unit sphere. Under his guidance and encouragement his students started the research on spherical harmonic analysis and approximation. In this paper, we incompletely introduce the main achievements in this area obtained by our group and relative researchers during recent 5 years (2001-2005). The main topics are: convergence of Cesaro summability, a.e. and strong summability of Fourier-Laplace series; smoothness and K-functionals; Kolmogorov and linear widths.  相似文献   

12.
In this paper we study best local quasi-rational approximation and best local approximation from finite dimensional subspaces of vectorial functions of several variables. Our approach extends and unifies several problems concerning best local multi-point approximation in different norms.  相似文献   

13.
In this paper, we study the commutators generalized by multipliers and a BMO function. Under some assumptions, we establish its boundedness properties from certain atomic Hardy space Hb^p(R^n) into the Lebesgue space L^p with p 〈 1.  相似文献   

14.
15.
<正>August 10-14,2015Beijing,ChinaThe International Congress on Industrial and Applied Mathematics(ICIAM)is the premier international congress in the field of applied mathematics held every four years under the auspices of the International Council for Industrial and Applied Mathematics.From August 10 to 14,2015,mathematicians,scientists  相似文献   

16.
<正>May 26,2014,Beijing Science is a human enterprise in the pursuit of knowledge.The scientific revolution that occurred in the 17th Century initiated the advances of modern science.The scientific knowledge system created by  相似文献   

17.
Let P(z)=∑↓j=0↑n ajx^j be a polynomial of degree n. In this paper we prove a more general result which interalia improves upon the bounds of a class of polynomials. We also prove a result which includes some extensions and generalizations of Enestrǒm-Kakeya theorem.  相似文献   

18.
Shanzhen  Lu  Lifang  Xu 《分析论及其应用》2004,20(3):215-230
In this paper, the authors study the boundedness of the operator [μΩ, b], the commutator generated by a function b ∈ Lipβ(Rn)(0 <β≤ 1) and the Marcinkiewicz integrals μΩ, on the classical Hardy spaces and the Herz-type Hardy spaces in the case Ω∈ Lipα(Sn-1)(0 <α≤ 1).  相似文献   

19.
Given the Laplace transform F(s) of a function f(t), we develop a new algorithm to find an approximation to f(t) by the use of the classical Jacobi polynomials. The main contribution of our work is the development of a new and very effective method to determine the coefficients in the finite series expansion that approximation f(t) in terms of Jacobi polynomials. Some numerical examples are illustrated.  相似文献   

20.
In applications it is useful to compute the local average empirical statistics on u. A very simple relation exists when of a function f(u) of an input u from the local averages are given by a Haar approximation. The question is to know if it holds for higher order approximation methods. To do so, it is necessary to use approximate product operators defined over linear approximation spaces. These products are characterized by a Strang and Fix like condition. An explicit construction of these product operators is exhibited for piecewise polynomial functions, using Hermite interpolation. The averaging relation which holds for the Haar approximation is then recovered when the product is defined by a two point Hermite interpolation.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号