排序方式: 共有7条查询结果,搜索用时 15 毫秒
1
1.
ON A LINEAR DELAY DIFFERENCE EQUATION WITH IMPULSES 总被引:2,自引:0,他引:2
IIntroductlonLet N denote the set of all Integers.FOr any a;b E N,define N(a)={a,a+1,…},N(a,b)二{a,a+1,…,b}when a<b.Consider the dlf卜巳renceequationl 凸x。+P。x。-。=0;nEN(0)andN4n。;2—“-””’”门二l0 凸X。,=~X。,,JENO);where A denotes the forward difference operator八。。=x。+l一 x。,{P。} Isa sequence ofnon-negative real numbers,{nj}Is a sequence ofnon-negativeIntegers with nj<nj+lfor j E N(1)and nj一 co as ;一 co,{4}Is a sequence。I优。且皿mb ers,… 相似文献
2.
3.
培养发散思维能力的一次教改尝试张勤勤(湖南大学应用数学系,长沙4100082)发散思维是创造性思维的核心。在数学教育中,引导学生进行发散思维的训练,对于培养创造型人才是极其重要的。所谓发散思维,即是一种从某一点出发,运用能想到的有关全部已知信息(条件... 相似文献
4.
Electrochemical, thermal, and photophysical properties of novel two- (BPODPA), four- (BBPOPA), and six-branch (TBPOA) triphenylamine chromophores are studied. The decomposition temperature of chro- mophores reaches 373 - 412 ℃. The electrochemical properties is explored by cyclic voltammetry. The ionization potential of chromophores is in the range of 5.14 - 5.18 eV. Excitation at 400 nm reveals emission peaks at 483 - 487 nm and the fluorescence quantum yields are 0.73 - 0.75 in CH2Cl2. Two-photon absorption (TPA) properties of chromophores are measured by nonlinear transmission method. The maximum TPA cross-section values are measured at 758 nm to be 20369 GM (1 GM=10^-50 cm^4 -s/photon) for TBPOA, 7024 GM for BBPOPA, and 1227 GM for BPODPA, respectively. When pumped with 800-nm laser irradiation, chromophores show strong two-photon excited blue-green fluorescence at 502 - 518 nm. These results provide a basis for understanding the electronic and optical properties of the conjugated multi-branch chromoohore in terms of the underlying molecular and electronic structures. 相似文献
5.
一类时滞神经网络差分系统周期解的吸引性 总被引:1,自引:0,他引:1
考虑一类 Mc Culloch- Pitts型信号函数的时滞神经网络差分系统周期解的吸引性 ,所得结果改进了文献 [6 ]相关结论。 相似文献
6.
考虑奇数阶中立型非线性微分方程d^n/dt^n(x(t)-P(t)g(x(t-τ)))+Q(t)h(x(t-σ))=0。本文在允许P(t)-1振动的条件下给出了该方程的几个线性化振动结果。 相似文献
7.
1