一种新型数字SDTV信源解码器的实现

本文实现了以专用芯片STi5518为核心器件的SDTV信源解码器.该解码器可配接不同制式的前端,组成完整的机顶盒方案;可对符合MPEG-2的视频流进行解码;可对AC-3或MPEG两种音频解码;另外,本系统还实现了硬盘录像和条件接收两个有特色的功能.本文重点叙述该信源解码器的硬件设计和实现原理.     

基于SNMPv3的RIPng路由协议设计与实现

本文在探讨SNMPv3和RIPng原理及特性的基础上,提出一种利用SNMPv3的SMUX协议管理RIPng系统诸多参数的实现方案,并对向其他IPv6路由协议和其他操作系统的移植做出展望.     

Low-power state encoding for partitioned FSMs with mixed synchronous/asynchronous state memory

Partitioned finite state machine (FSM) architectures in general enable low-power implementations and it has been shown that for these architectures, state memory based on both synchronous and asynchronous storage elements gives lower power consumption compared to their fully synchronous counterparts. In this paper we present state encoding techniques for a partitioned FSM architecture based on mixed synchronous/asynchronous state memory. The state memory, in this case, is composed of a synchronous local state memory and an asynchronous global state memory. The local state memory uses synchronous storage elements and is shared by all sub-FSMs. The global state memory operates asynchronously and is responsible for handling the interaction between sub-FSMs. Even though the partitioned FSM contains the asynchronous mechanism, its input/output behaviour is still cycle by cycle equivalent to the original monolithic synchronous FSM. In this paper, we discuss the low-power state encoding method for the implementation of partitioned FSM with mixed synchronous/asynchronous state memory. For the local state assignment a, what we call, state-bundling procedure is presented to enable states residing in different sub-FSMs to share the same state codes. Based on state-bundles, two state encoding techniques, in which one is the employment of binary encoding and the other is the further optimization for low power, are compared.     

Context-aware wireless sensor networks for assisted living and residential monitoring

Improving the quality of healthcare and the prospects of "aging in place" using wireless sensor technology requires solving difficult problems in scale, energy management, data access, security, and privacy. We present AlarmNet, a novel system for assisted living and residential monitoring that uses a two-way flow of data and analysis between the front- and back-ends to enable context-aware protocols that are tailored to residents' individual patterns of living. AlarmNet integrates environmental, physiological, and activity sensors in a scalable heterogeneous architecture. The SenQ query protocol provides real-time access to data and lightweight in-network processing. Circadian activity rhythm analysis learns resident activity patterns and feeds them back into the network to aid context-aware power management and dynamic privacy policies.     

Efficient ID-based registration protocol featured with user anonymity in mobile IP networks

A secure and efficient ID-based registration protocol with user anonymity is proposed in this paper for IP-based mobile networks. The protocol minimizes the registration delay through a minimal usage of the identity (ID)-based signature scheme that eliminates expensive pairing operations. User anonymity is achieved via a temporary identity (TID) transmitted by a mobile user, instead of its true identity. Additional replay protection from a Foreign Agent (FA) is included in the registration messages to prevent a possible replay attack. A formal correctness proof of the protocol using Protocol Composition Logic (PCL) is presented. Numerical analysis and computer simulation results demonstrate that the proposed protocol outperforms the existing ones in terms of the registration delay, the registration signaling traffic, and the computational load on a Mobile Node (MN) while improving security. For example, the proposed protocol reduces the registration delay up to 49.3 percent approximately, comparing to Yang?s protocol.     

用改进变异粒子算法实现突发威胁下的无人机航迹规划

针对无人飞行器航迹规划问题,提出一种改进变异粒子群算法及航迹节点拓展法,有效解决了突发威胁下的航迹规划问题,并进行仿真验证。通过引入维量化活性度解决了粒子群算法搜索后期速度下降问题,通过相对坐标转换避免了采用一元多项式函数作为水平航迹丢失部分解的情况。仿真表明,利用改进的变异粒子群算法能够有效地提高搜索速度和精度,适用于突发威胁下的航迹规划问题。     

三元乙丙橡胶绝热层的烧蚀特性研究

基于一种半装药的高过载地面模拟试验发动机,针对不同推进剂铝粉含量和绝热层材料开展了三次发动机过载试验,获得了绝热层宏观烧蚀规律,通过电镜分析了EPDM的烧蚀模型。结果表明:(1)三元乙丙橡胶绝热层较丁羟基绝热层更抗烧蚀、抗冲刷;(2)推进剂的铝粉含量越高,燃气对三元乙丙绝热层的冲刷越严重,绝热层的烧蚀率越大;(3)通过试验分析,验证了三元乙丙绝热层的碳化、热解、基体的烧蚀模型。     

舰载软硬防雷武器综合对抗智能鱼雷方案研究

针对舰艇对抗智能声自导鱼雷的问题,提出了综合使用两型软硬防雷武器即悬浮式声诱饵和悬浮式深弹的对抗方法,确定了二者的发射顺序,给出了两种可行的布放方案;采用统计模拟的方法,对两种布放方案的对抗效果进行了仿真,通过分析仿真结果,对舰载软硬防雷武器对抗智能声自导鱼雷的方案进行了优选;通过改进悬浮式声诱饵与悬浮式深弹阵之间的布放间隔,有效提高了舰艇的生存概率,为提高软硬防雷武器综合使用的作战能力提供了决策依据。     

正癸烷云雾气液两相浓度对其燃爆参数的影响

为研究正癸烷云雾在相同粒径条件下气液两相浓度对燃爆参数的影响,用测量液雾粒径与浓度的光学测量系统和20 L二次脉冲气动喷雾多相爆炸测试系统,测量了基于相同索特平均直径D32,不同气液两相浓度的正癸烷云雾,实验研究了其燃爆参数。结果表明,在D32为38.11μm,点火能为40.32 J的条件下,正癸烷气液两相云雾燃爆下限总浓度为199.29 g·m-3,对应的液相质量浓度为151.34 g·m-3,气相体积浓度为0.77%(V/V)。在可燃浓度范围内,最大爆温峰值与最大爆压峰值分别为812℃和0.97 MPa。在D32为38.11μm的条件下,正癸烷云雾液相浓度对燃爆下限影响较小,而影响正癸烷云雾燃爆下限的主导因素是气相浓度。     

基于JAIN SLEE的业务逻辑执行环境的设计与实现

本文简要分析了下一代业务逻辑执行环境(SLEE,Service Logic Execution Environment)JAIN SLEE规范,在此基础上给出了基于规范的SLEE设计与实现.