简要介绍网络模拟软件N S(N etw ork S im u lator),分析网络模拟软件N S在教学中应用的优点。认为N S应用于计算机网络课程进行辅助教学和辅助实验具有经济性、方便性、针对性和可重复性等优点。提出应用网络模拟软件N S进行课堂演示、实验比较、设计开发三种教学。这样可以让学生通过观看网络运作动画、分析网络性能结果和设计简单网络实体,能让学生更容易、深入地理解网络协议和算法的复杂行为,收到更好的教学效果。
This paper studies the Kapchinsky-Vladimirsky (K-V) beam through a triangle periodic-focusing magnetic field by using the particle-core model. The beam halo-chaos is found, and an idea of Gauss function controller is proposed based on the strategy of controlling the halo-chaos. It performs multiparticle simulation to control the halo by using the Gauss function control method. The numerical results show that the halo-chaos and its regeneration can be eliminated effectively, and that the radial particle density is uniform at the centre of the beam as long as the control method and appropriate parameter are chosen.