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One-dimensional perturbed neutral delay differential equations of the form (x(t)−P(t,x(t−τ)))′=f(t,xt)+g(t,xt) are considered assuming that f satisfies −v(t)M(φ)?f(t,φ)?v(t)M(−φ), where M(φ)=max{0,maxs∈[−r,0]φ(s)}. A typical result is the following: if ‖g(t,φ)‖?w(t)‖φ‖ and , then the zero solution is uniformly asymptotically stable providing that the zero solution of the corresponding equation without perturbation (x(t)−P(t,x(t−τ)))′=f(t,xt) is uniformly asymptotically stable. Some known results associated with this equation are extended and improved. 相似文献
134.
周英告 《高校应用数学学报(英文版)》2003,18(1):53-58
§ 1 IntroductionConsiderthenonautonomousdelaylogisticdifferenceequationΔyn =pnyn( 1 - yτ(n) ) ,n =0 ,1 ,2 ,...,( 1 1 )wherepn ∞n =0 isasequenceofpositiverealnumbers ,τ(n) ∞n =0 isanondecreasingsequenceofintegers,τ(n) <nandlimn→∞τ(n) =∞ ,Δyn=yn +1- yn.Motivatedbyplausibleapplications… 相似文献
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HAO YingHang GONG YuBing LIN Xiu & WANG Li School of Physics Ludong University Yantai China 《中国科学B辑(英文版)》2011,(5)
The spiking behavior with varying time delay in scale-free networks of Hodgkin-Huxley neurons with non-Gaussian noise has been studied,and the effect of non-Gaussian noise on the delay-induced spiking behavior is discussed. It was found that multiple spatio-temporal resonances occur when the delay lengths are integer multiples of the spiking periods,and the resonances may be strengthened when the non-Gaussian noise is appropriate. This result shows that time delays can optimize the spiking temporal regulari... 相似文献
137.
二层信用策略下部分延期付款的库存模型 总被引:1,自引:0,他引:1
当前二层信用期相关文献考虑的都是零售商提供给其顾客相同的信用期,但现实中零售商往往会根据物品的种类不同提供给顾客不同的信用期.为研究此问题,建立了优化供货周期使零售商平均相关成本最小的库存模型,证明了最优供货周期的存在性,并给出实例加以说明. 相似文献
138.
In this paper, the issue of finite-time lag synchronization of coupled reaction–diffusion systems with time-varying delay (CRDSTD) is considered. A periodically intermittent controller is designed such that drive system and corresponding response system can achieve finite-time lag synchronization. By using graph theory and Lyapunov method, two sufficient criteria are presented to guarantee the finite-time lag synchronization of CRDSTD. Moreover, the time of achieving lag synchronization of CRDSTD is estimated. Finally, a numerical example is given to show the effectiveness of the proposed results. 相似文献
139.
Relative position determination of a lunar rover using high-accuracy multi-frequency same-beam VLBI 总被引:2,自引:0,他引:2
LIU QingHui CHEN Ming XIONG WeiMing QIAN ZhiHan LI JinLing HAO WangHong WANG GuangLi ZHENG WeiMin GUAN Di ZHU RenJie WANG WeiHua ZHANG XiuZhong JIANG DongRong SHU FengChun PING JinSong & HONG XiaoYu Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China Center for Space Science Applied Research Beijing Lunar Explorer Engineering General Department Beijing ... 《中国科学:物理学 力学 天文学(英文版)》2010,(3)
Multi-frequency same-beam VLBI means that two explorers with a small separation angle are simultaneously observed with the main beam of receiving antennas. In the same-beam VLBI, the differential phase delay between two explorers and two receiving telescopes can be obtained with a small error of several picoseconds. The differential phase delay, as the observable of the same-beam VLBI, gives the separation angular information of the two explorers in the celestial sphere. The two-dimensional relative position on the plane-of-sky can thus be precisely determined with an error of less than 1 m for a distance of 3.8×105 km far away from the earth, by using the differential phase delay obtained with the four Chinese VLBI stations. The relative position of a lunar rover on the lunar surface can be determined with an error of 10 m by using the differential phase delay data and the range data for the lander when the lunar topography near the rover and the lander can be determined with an error of 10 m. 相似文献
140.
一类积分微分方程概周期解的存在性和唯一性 总被引:1,自引:0,他引:1
考虑具无穷时滞的非线性积分微分方程概周期的存在性和唯一性问题,利用矩阵测度和不动点方法获得了一类方程的概周期的存在性和唯一性的充分条件,推广了相应文献的结果. 相似文献