Dynamic Prediction based Multi Queue (DPMQ) drop policy for probabilistic routing protocols of delay tolerant network

Two most important issues should be considered to achieve data delivery in DTN networking: routing protocols for the network and intelligent buffer management policy for everyone node in the network. The routing scheme decides which messages should be forwarded when nodes meet, and the buffer management policy determines which message is purged when the buffer overflows in a node. This study proposes a buffer management policy named as Dynamic Prediction based Multi Queue (DPMQ) for probabilistic routing protocols. It works by classification of local buffer into three queues of messages, which are DCTL, HPTL and LPTL. The simulation results have proven that the DPMQ performs well as compared to DLA, DOA, MOFO, LIFO, LEPR and LIFO in terms of reducing the message relay, message drop, hop counts average and overhead while rising in the delivery probability.     

基于ANSYS的滚水坝稳定与应力分析

以碗牛坝水利工程为例分别利用刚体极限平衡法和有限元法计算溢流重力坝沿坝基面的抗滑稳定,并对这两种方法的分析结果进行了对比,总结两种方法各自的优缺点,同时对坝体基底应力进行简要分析,并提出了需要进一步研究和解决的问题。     

立体视频分级网络传输码率平滑方法

立体视频视角分级后会造成各视角码流的码率波动过大的现象,对网络传输及终端造成冲击.为解决该问题,提出一种自适应双缓冲码率平滑策略实现视角分级后的码率平滑.该方法根据视角分离后码率抖动的特点,在发送端对各视角码流进行两级缓冲码率平滑.不同视角的码流经过视角分离后存入各自缓冲区中并按帧率向第2级发送码流进行第1级平滑,经过...     

CDNs基于缓存区预测机制的负载均衡算法

提出了一种基于缓存队列长度动态预测机制的请求重定向（BMP）算法,采用M/M/1排队模型对分布式内容分发网络的负载均衡算法进行了描述,基于队列长度预测的机制减少了分发请求过程中不必要的重定向,同时可以克服单点过载问题.仿真分析结果显示,相比于之前的负载均衡控制策略算法,所提出的BMP算法对服务器缓存区队列长度的均衡效果更优;同时,由于减少了不必要的重定向,也降低了请求响应过程的时延成本.     

弹性缓冲结构在被动式液压加载系统研制中的应用研究

提出在被动式电液伺服加载系统的设计中应用弹性缓冲结构来减缓加载过程中因对象运动而产生的多余力矩对系统性能的影响。讨论了弹性缓冲结构的引入方式、分析了弹性缓冲的作用 ,并对采用弹性缓冲结构的被动式电液伺服加载系统进行了数字仿真和实验研究。结果表明在被动式电液伺服加载系统中采用弹性缓冲结构可以达到有效抑制多余力矩、提高系统性能的作用。     

转盘减震系统在桥吊结构中的应用

在常遇地震荷载作用下，桥吊需要保证其结构稳定性，满足抗倾覆的稳定性要求，满足正常的生产使用。但桥吊结构是严重偏心的结构，当不采取适当的抗震措施时往往会引起陆侧腿抬起，海侧腿压力太大而发生失稳破坏。文章在对桥吊中转盘结构的抗震减震效果分析的基础上，提出了采用转盘结构进行减震设计时的评价指标，并对影响这些评价指标的变量进行了参数分析，说明转盘减震系统中阻尼器系统和弹簧系统正确选用的重要性。并以一实例说明了转盘减震系统的效果。为此类结构的减震设计提供了依据。     

Distinguishing crystallographic misorientations of lanthanum zirconate epilayers on nickel substrates by electron backscatter diffraction

Electron backscatter diffraction (EBSD) was used for distinguishing crystallographic orientations and local lattice misfits of a La₂Zr₂O₇ (LZO) buffer layer epitaxially grown on a cube textured Ni-5.%W (Ni-W) substrate for a YBCO superconductor film. Orientation data were obtained from the LZO epilayer using low energy primary electrons (5 keV) and from the Ni-W substrate by increasing the voltage to 15 keV. In-plane and out-of-plane orientations of the LZO epilayer were revealed with respect to its Ni-W substrate. A strong {1 0 0} 〈0 1 1〉 rotated-cube texture in the LZO epilayer was formed on the {1 0 0} 〈0 0 1〉 cube-textured Ni-W substrates. LZO and Ni in-plane crystallographic axes are related by an expected 45° rotation. The step-misorientations and the local misfit strains between the LZO epilayer and the substrate were also analyzed.     

Finite-time boundedness filtering for discrete-time Markovian jump system subject to partly unknown transition probabilities

This paper investigates the problem of finite-time boundedness filtering for discrete-time Markovian jump system subject partly unknown transition probabilities. By using the multiple Lyapunov function approach, a novel sufficient condition for finite-time bounded of _H∞$H_{\infty }$ filtering is derived and the system trajectory stays within a prescribed bound during a specified time interval. Finally, an example is provided to illustrate the usefulness and effectiveness of the proposed method.     

砂-膨润土混合物膨胀力影响因素的研究

在放射性废料地质处置中，砂－膨润土混合物可用作缓冲回填材料，因而引起了人们对其性能的更加关注。通过室内试验，初步研究了砂－膨润混合物在不同含水量（4％－17．9％）、膨润土含量（10％－50％）和干密度（1．35－1．84g/cm^2）状态下的膨胀性能。通过对试验结果的分析，获得了一些有意义的结论。试验研究表明：砂－膨润土混合物的膨胀性能取决于其干密度、膨润土含量和含水量。含水量小于塑限含水量时，其膨胀稳定后的影响因素的分析中，使用蒙脱石的填充率这一参数来描述膨胀力。把粘土矿物含量、干密度的影响都统一到蒙脱石填充率对膨胀力的影响，建立了蒙脱石密度与膨胀力的函数关系。     

野三关地下暗河分布及其对隧道的影响

根据野三关隧道区多阶段的水文地质调查、钻探、示踪试验和地下水观测等成果及开挖揭示,对该区地下暗河的发育进行了重新分析和总结,全面阐述了暗河对隧道的影响,为正在施工的隧道提供参考。