厄米-双曲余弦-高斯光束的瞄准稳定性

用失调叠加积分的方法 ,对厄米双曲余弦高斯光束的瞄准稳定性作了研究 ,得到了厄米双曲余弦高斯光束失调因子 ηm2 的精确解析公式和近似解析公式 ,并用数值计算了相对横向偏移和相对角向偏移对失调因子ηm2 的影响以及对精确解析公式和近似解析公式的适用范围作了分析和说明。     

抽吸和压力梯度在层流边界层转捩过程中的作用

用空间模式的二次稳定性理论研究了抽吸和压力梯度对边界层三维亚谐扰动流动稳定性的影响．数值结果表明，固体边界上的抽吸有明显的层流控制作用，逆压梯度则有较强的不稳定作用．     

STABILITY NUMBER IN SUBCLASSES OF P5-FREE GRAPHS

Two new hereditary classes of P5-free graphs where the stability number can be found in polynomial time are proposed. They generalize several known results.     

瑞福特荣登电子政务IT百强榜

2004年第三届IT100强排行榜近日在北京揭晓．在2000多个参选企业中选出电子政务业务实力最强的100家企业。在视讯行业．深圳瑞福特信息技术公司凭借在电子政务方面的出色业绩成功入围．成为少数进八该排行榜的中国本土视讯企业之一。瑞福特发展步伐惊人．短短几年内已经发展成为大中华     

二阶变系数线性微分方程组的稳定性

本文讨论方程组的零解的稳定性,推广了文[2]的相应结果.     

会聚圆偏振强激光作用下的原子行为

文中考虑了在会聚的圆偏振强激光作用下的原子行为,结果表明,圆偏振强激光下的原子势,在r≤R₀时为一由R₀∝I^1/2ω^-2决定的均匀势场,而在r≥R₀时仍表现为Coulomb势.在此基础上,求解了原子能级移位和波函数的空间分布问题.可以看出,原子束缚能级随激光强度的加大而变浅和分裂,波函数的空间分布也随之剧烈扩大.文中还讨论了一些相关的物理问题.     

色屏蔽效应与重子谱

利用从格点规范理论计算得出的,包括色屏蔽效应的禁闭位势;研究了重子结构,计算了重子谱及相应状态下的夸克分布的均方根半径.     

有理同时Chebyshev逼近的一致强唯一性

本文研究了广义有理同时 Chebyshev 逼近的一致强唯一性.首先,我们举例说明经典的 Chebyshev 逼近的结果不能直接推广到同时 Chebyshev 逼近情形,其次给出了使 inf_(F∈Γ)γ(F)>0的充分条件.其中γ(F)是 F 的广义有理同时 Chebyshev 逼近的强唯一常数.最后,我们研究了所给条件的必要性.     

EXPONENTIAL STABILITY AND PERIODIC SOLUTION OF HYBRID BIDIRECTIONAL ASSOCIATIVE MEMORY NEURAL NETWORKS WITH DISCRETE DELAYS

In this paper, we study the existence, uniqueness, and the global exponential stability of the periodic solution and equilibrium of hybrid bidirectional associative memory neural networks with discrete delays. By ingeniously importing real parameters di > 0 (i = 1,2, …, n) which can be adjusted, making use of the Lyapunov functional method and some analysis techniques, some new sufficient conditions are established. Our results generalize and improve the related results in [9]. These conditions can be used both to design globally exponentially stable and periodical oscillatory hybrid bidirectional associative neural networks with discrete delays, and to enlarge the area of designing neural networks. Our work has important significance in related theory and its application.     

PERSISTENCE AND GLOBAL STABILITY FOR TWO-SPECIES NONAUTONOMOUS PREDATOR-PREY SYSTEM WITH DIFFUSION AND TIME DELAY

In this paper, a non-autonomous predator-prey model with diffusion andcontinuous time delay is studied, where the prey can diffuse between two pat-ches of a heterogeneous environment with barriers between patches, but for thepredator, the diffusion does not involve a barrier between patches, further itis assumed that all the parameters are time-dependent. It is shown that thesystem can be made persistent under some appropriate conditions. Moreover,sufficient conditions that guarantee the existence of a unique periodic solutionwhich is globally asymptotic stable are derived.