SAN多协议路由器流控机制的设计与实现

为了保障SAN多协议路由器高速稳定的运行并提高系统的兼容性,提出一种存储区域网络下的流控机制。SAN多协议路由器底层与上层软件间采用基于门阈的流控,进行速率匹配,使系统能够正常运行。与连接的设备间采用基于credi(t接收缓冲区数量)的流控以保证SAN路由器系统与连接设备间速率相匹配。实验结果表明引入流控机制后SAN路由器能与各种磁盘阵列及hba卡等设备正常通信,具备很好的兼容性,并能保证在最高2Gbps高速情况下稳定运行。     

案例教学法在电机与拖动教学中的应用研究

针对自动化专业电机与拖动专业课课堂教学中的常规教学法,提出了"案例式"教学法。相对于常规教学法中学生被动地接受教师传授的知识的缺点,"案例式"教学法能让学生主动接受教师所传授的知识,激发学生学习的积极性,同时能提高学生课堂听课效率。     

IPTV及手机电视换台加速策略初探

网络电视及手机电视的换台时延如果较长,就容易影响到用户的收视体验.本文从这一问题出发,给出了一种方法,即通过为组播复制点等网络节点添加缓存资源,用于暂存节目数据,并以突发的形式传递给STB(机顶盒)或手机终端,从而实现换台加速的目的.     

高硼硅3.3玻璃和可伐合金的激光封接界面研究

采用多道激光透射封接技术,对大尺寸3.3高硼硅玻璃-可伐合金封接工艺进行了探索性研究,采用正交实验方法,实现了两种材料的可靠封接.确定了优化工艺参数:扫描速度为25mm/s,激光功率为1OOW,离焦量为+40mm,扫描次数2次.通过使用SEM.EDX以及激光共聚焦显微镜观测硼硅玻璃-可伐合金的激光封接断面,对比相图,就结合界面的特征和机理进行了初步分析,Fe2SiO4化合物的形成是两者能够可靠封接的主要原因,确定了两种材料的激光可封接性.     

Throughput-based fair bandwidth allocation in OBS networks

Fair bandwidth allocation (FBA) has been studied in optical burst switching (OBS) networks, with the main idea being to map the max-min fairness in traditional IP networks to the fair-loss probability in OBS networks. This approach has proven to be fair in terms of the bandwidth allocation for differential connections, but the use of the ErlangB formula to calculate the theoretical loss probability has made this approach applicable only to Poisson flows. Furthermore, it is necessary to have a reasonable fairness measure to evaluate FBA models. This article proposes an approach involving throughput-based-FBA, called TFBA, and recommends a new fairness measure that is based on the ratio of the actual throughput to the allocated bandwidth. An analytical model for the performance of the output link with TFBA is also proposed.     

Stimulation of negative magnetoresistance by an electric field and light in silicon doped with boron and manganese

It is experimentally ascertained that light stimulates the negative magnetoresistance observed in a high electric field in silicon doped with boron and manganese. The optimum conditions (the electric field, temperature, illumination, and resistivity of the material) for observation of the largest magnitude of negative magnetoresistance in (Si:B):Mn are determined. The dependence of the negative magnetoresistance on the concentration of compensating impurity is established.     

Optimal block boundary pre/postfiltering for wavelet-based image and video compression.

This paper presents a pre/postfiltering framework to reduce the reconstruction errors near block boundaries in wavelet-based image and video compression. Two algorithms are developed to obtain the optimal filter, based on boundary filter bank and polyphase structure, respectively. A low-complexity structure is employed to approximate the optimal solution. Performances of the proposed method in the removal of JPEG 2000 tiling artifact and the jittering artifact of three-dimensional wavelet video coding are reported. Comparisons with other methods demonstrate the advantages of our pre/postfiltering framework.     

New cross-Layer design approach to ad hoc networks under Rayleigh fading

We propose a new cross-layer design employing the predictability of Rayleigh channels to improve the performance of ad hoc networks. In addition, we propose a Markov model for Rayleigh channels and an innovative Markov model for IEEE 802.11 distributed coordination function. By combining these two models, we derive the theoretical expressions for network throughput, packet processing rate, packet loss probability, and average packet delay under Rayleigh channels. The simulation of the proposed cross-layer design is also carried out. It is shown that the new approach improves the network throughput, reduces unnecessary packet transmissions and therefore reduces packets lost. We also show that there is a close match between the analytical and the simulation results which confirms the validity of the analytical models.     

竞速

从造型个性的数码摄像机XL1S的一鸣惊人到EOS 300D犹如泰山压顶之势占领市场，佳能总是比别人领先了一步，这次200万像素级家用摄像机MVS 1Si的登场又让人感觉到佳能的领先速度了。[编者按]     

(111)晶向碲锌镉晶片双面腐蚀的对比

通过对材料减薄，并采用红外透射显微镜观察的手段，实现了对A面和B面腐蚀坑的同时观察.结果发现采用标准腐蚀剂在同一晶片的（111) A和（111) B面上形成的腐蚀坑大都不存在对应关系，深度腐蚀的实验也发现，表面腐蚀坑所对应的缺陷只局限于10μm的表层内，这表明大部分腐蚀坑所对应的不是通常认为的穿越位错. 进一步分析的结果表明，不同腐蚀剂形成的腐蚀坑所对应的缺陷有可能是不同类型的位错，甚至也可能起源于微沉淀物，通常将碲锌镉材料的腐蚀坑所对应的缺陷简单地归结为材料的位错是缺乏实验依据的.