As virtual networks services emerge increasingly with higher requirement of flexibility and robust, great complex challenges caused by physical-layer impairments are presented to the elastic optical networks (EON). Aimed to solve this problem, this paper proposes a physical impairment awareness based virtual network mapping stragegy of EON. The physical impairments awareness model is established, including both of linear factors and nonlinear ones. On this basis, this paper proposes a virtual network mapping strategy with detailed procedures, combined with node importance factors during the virtual network mapping procedure. Test results show that the proposed approach is able to reduce blocking rate and enhance services supporting ability of EON.

As internet services newly emerge with diversity and complexity, great challenges and demands are presented to both IP network and optical network to support various services. Aimed to solve this problem, this paper proposes a light-weighted echo-state-network (LW-ESN) based services awareness scheme of the software defined IP and optical converged network. This LW-ESN model adopts the ring topology structure inside and generates the probability output result to determine the quality of service policy of IP and optical converged network. Moreover, the LW-ESN based service awareness engine is also designed in controller node of IP and optical converged network to perform services awareness by obtaining service traffic parameters from IP and optical layers, together with necessary working procedure. Simulation results show that the proposed approach is able to improve the services-oriented supporting ability in terms of blocking rate and delay time.

为更好地理解放电腔内等离子体物理机制, 对Kaufman型离子推力器放电腔进行了数值研究, 其中初始电子采用粒子模拟的方法处理, 二次电子和离子采用漂移-扩散流体近似描述。模拟结果与已有实验测量数据进行对比表明：所采用计算方法适用于放电腔内等离子体流动规律的数值研究;模拟得到的稳态下等离子体分布及变化规律与实验测量数据相吻合;磁场的设计对初始电子起到显著的约束作用, 有效地提高了其与工质气体的电离碰撞几率;二次电子的精确描述还需在流体方程中耦合磁场效应。

采用粒子网格单元和蒙特卡罗碰撞方法,建立了离子推力器羽流场的2维轴对称模型,对其特性进行了数值模拟,并将模拟结果与实验测量数据进行了对比分析。研究结果表明:数值模拟结果与实验测量值基本一致,模型可以很好地评估离子推力器的羽流特性;返流区离子数密度达到1014 m-3量级,会对航天器表面产生污染;背压对束流区域外电荷交换离子影响较为显著,不可忽略。