MPEG 2实时解码中的输入缓冲器控制

分析了ＭＰＥＧ２ 的时序模型，研究了理想解码器的输入缓冲器工作过程以及实际实时解码器解码开始的时刻、解码非瞬时、码流非平稳等因素对输入缓冲器的影响，指出实际解码器的输入缓冲器必须增大。在输入缓冲器容量受限制的情况下，给出了输入缓冲器控制策略。该策略已经成功地应用于作者研制的高清晰度电视功能样机中。

基于GA-BP神经网络对控制棒水力缓冲器的性能预测和结构参数优化

为通过遗传算法(GA)改进的反向传播(BP)神经网络模型预测控制棒组件水力缓冲器的缓冲性能,并实现结构参数优化,本研究对一种特定的控制棒组件水力缓冲器静水中的落棒进行模拟试验,变换试验可调参数,设置不同的试验工况,获取了大量的试验数据,通过GA-BP神经网络对控制棒组件落棒过程的最大冲击力进行预测,并构建优化数学模型,使用非线性规划函数(fmincon)进行求解,获得更优的结构参数组合。结果表明:GA-BP神经网络模型相较于BP神经网络模型具有更高的预测精度,通过fmincon函数可以实现对控制棒组件最大冲击力优化数学模型的快速求解。因此,本文的优化方法可为水力缓冲器的结构优化设计提供一定的参考。

Influence of Buffering Pressure Characteristics on Shift Clutch Engagement Process

The dynamic math model of shift clutch in engagement process was determined on the basis of hydraulic buffering valve and shift clutch of a power shift steering transmission. The influence of buffering pressure characteristic on shift clutch engagement process was analyzed. The study results could be used to the characteristics match of the shift clutch with the hydraulic system of the high speed tracked vehicle power shift steering transmission and the performance prediction.

STUDY AND ENHANCEMENT ON BUFFER MANAGEMENT FOR SMOOTH HANDOVER IN MIPV6

For improving Transfer Control Protocol (TCP) performance in mobile environment,smooth handover with buffer management has been proposed to realize seamless handovers. However in our simulation, even if smooth handover in Mobile IPv6 (MIPv6) is implemented, TCP can not always achieve better performance due to packets forwarding burst. Based on the study of buffer management for smooth handover, this paper proposes an enhanced buffer management scheme for smooth handover to improve TCP performance. In this scheme, a packet-pair probing technology is adopted to estimate the available bandwidth of the new path from Previous router (Prtr) to Mobile Node (MN), which will be used by Prtr to control the buffered packets forwarding. The simulation results demonstrate that smooth handover with this scheme can achieve better TCP performance than the original scheme.