目前,已经有许多的机遇速率的流量控制方法应用于 ABR 网络。这些方法中大多都能提高主动连接的公平性和连接利用率。同时,也给交换机带来更大的复杂性。本文中提出了一个流量控制方法,将部分速率计算工作从交换机转移到终端系统中进行...目前,已经有许多的机遇速率的流量控制方法应用于 ABR 网络。这些方法中大多都能提高主动连接的公平性和连接利用率。同时,也给交换机带来更大的复杂性。本文中提出了一个流量控制方法,将部分速率计算工作从交换机转移到终端系统中进行。结果表明,该方法能减少交换机的速率计算工作及交换复杂性,还降低了交换机在每一时间间隔内计算每条链路负载因子的难度,使占用队列长度保持在稳定状态。仿真结果表明该方法具有比 ERICA+算法更好的运行效果。展开更多
The paper studies a kind of improved photonic crystal fiber gratings fabricated by CO2 laser heating method. The effective refractive index of cladding induced by periodic air hole deformation is computed using multip...The paper studies a kind of improved photonic crystal fiber gratings fabricated by CO2 laser heating method. The effective refractive index of cladding induced by periodic air hole deformation is computed using multipole method, and the rela-tionship between the effective refractive index and the collapse of air-holes is discussed, thereby the modulation expression of effective refractive index is obtained. The grating transmission characteristics are simulated. The results indicate that with the diameter of air-holes increasing from 3.3 ~m to 3.7 μm, the resonance wavelength shows blue-shift, the resonance peak intensifies, and the bandwidth becomes narrow. As the collapse degree of cladding enhances, the resonance wave- length shows red-shift, the transmission increases, and the bandwidth tends to narrow.展开更多
文摘目前,已经有许多的机遇速率的流量控制方法应用于 ABR 网络。这些方法中大多都能提高主动连接的公平性和连接利用率。同时,也给交换机带来更大的复杂性。本文中提出了一个流量控制方法,将部分速率计算工作从交换机转移到终端系统中进行。结果表明,该方法能减少交换机的速率计算工作及交换复杂性,还降低了交换机在每一时间间隔内计算每条链路负载因子的难度,使占用队列长度保持在稳定状态。仿真结果表明该方法具有比 ERICA+算法更好的运行效果。
基金supported by the National Basic Research Pragram of China (973 Pragram) (No.2010CB327801)the Natural Science Foundation of Hebei Province (No.F2010001286)the Applied Basic Research Programs of Hebei Province (No.10963526D)
文摘The paper studies a kind of improved photonic crystal fiber gratings fabricated by CO2 laser heating method. The effective refractive index of cladding induced by periodic air hole deformation is computed using multipole method, and the rela-tionship between the effective refractive index and the collapse of air-holes is discussed, thereby the modulation expression of effective refractive index is obtained. The grating transmission characteristics are simulated. The results indicate that with the diameter of air-holes increasing from 3.3 ~m to 3.7 μm, the resonance wavelength shows blue-shift, the resonance peak intensifies, and the bandwidth becomes narrow. As the collapse degree of cladding enhances, the resonance wave- length shows red-shift, the transmission increases, and the bandwidth tends to narrow.
