摘要：Many researchers have developed new calculation methods to analyze seismic slope stability problems, but the conventional pseudo-static method is still widely used in engineering design due to its simplicity. Based on the Technical Code for Building Slope Engineering（GB 50330-2013） of China and the Guidelines for Evaluating and Mitigating Seismic Hazards in California（SP117）, a comparative study on the pseudo-static method was performed. The results indicate that the largest difference between these two design codes lies in determination of the seismic equivalence reduction factor( f;). The GB 50330-2013 code specifies a single value for f;of 0.25. In SP117, numerous factors,such as magnitude and distance, are considered in determining f;. Two case studies show that the types of slope stability status evaluated by SP117 are in agreement with those evaluated by the seismic time-history stability analysis and Newmark displacement analysis. The factors of safety evaluated by SP117 can be used in practice for safe design. However, the factors of safety evaluated by GB 50330-2013 are risky for slope seismic design.

摘要：针对冗余惯性测量单元(inertial measurement unit,IMU)姿态估计问题,通过采用不变扩展卡尔曼滤波器结构,将被估计系统动态特性建模为矩阵李群和偏差向量的混合模型,从而设计基于协方差在线校正的局部IMU姿态估计器.在此基础上,采用对数映射将李群不确定性映射到向量空间,进而构造依赖于局部姿态估计器参数的分布式融合问题,从而设计基于李群的鲁棒协方差交叉融合准则.特别地,为解决局部估计器之间互协方差未知的问题,通过引入先验容差来约束未知互协方差,从而提供低保守性的协方差上界以提高融合估计性能,形成一种具有双层结构的冗余IMU姿态估计方法.最后在下肢外骨骼康复机器人平台上验证所提出算法的有效性.

摘要：为在试验水池中精确模拟以"波浪谱"描述的海浪不规则波,给出了直接生成造波机运动控制所需的离散时间序列数的计算模型.基于通用计算机的开放式多轴运动控制器设计了电机伺服驱动的模拟不规则波造波控制系统,采用数字比例、积分、微分(PID)及速度前馈控制技术解决了系统所要求的高精度伺服位置控制和多电机同步控制问题,通过对离散时间序列数的样条光顺使伺服电机具有加速度连续的良好运动特性.系统的控制模型以自学习的方法对比反馈的实际波形进行输出位置量的矫正,以获得准确的模拟波浪.

摘要：To evaluate the therapeutic efficiency of tissue-engineered human corneal endothelia (TE-HCEs) on rabbit primary corneal endotheliopathy (PCEP),TE-HCEs reconstructed with monoclonal human corneal endothelial cells (mcHCECs) and modified denuded amniotic membranes (mdAMs) were transplanted into PCEP models of New Zealand white rabbits using penetrating *** TE-HCEs were examined using diverse techniques including slit-lamp biomicroscopy observation and pachymeter and tonometer measurements in vivo,and fluorescent microscopy,alizarin red staining,paraffin sectioning,scanning and transmission electron microscopy observations in *** corneas of transplanted eyes maintained transparency for as long as 200 d without obvious edema or immune *** corneal thickness of transplanted eyes decreased gradually after transplanting,reaching almost the thickness of normal eyes after 156 d,while the TE-HCE non-transplanted eyes were turbid and showed obvious corneal *** polygonal corneal endothelial cells in the transplanted area originated from the TE-HCE *** intact monolayer corneal endothelium had been reconstructed with the morphology,cell density and structure similar to those of normal rabbit corneal *** conclusion,the transplanted TE-HCE can reconstruct the integrality of corneal endothelium and restore corneal transparency and thickness in PCEP *** TE-HCE functions normally as an endothelial barrier and pump and promises to be an equivalent of HCE for clinical therapy of human PCEP.

摘要：连续混沌调频雷达的发射信号采用连续混沌信号实现信号调频,其性能逼近噪声调频信号,避免了离散调频设计中存在的前提限制(如:脉冲持续时间长、频率跳变等).基于混沌动力学理论,提出了连续混沌调频雷达的波形设计方法.该方法根据连续混沌调频信号的动力学模型,设定时间尺度变换函数,调制处于正弦振荡的Colpitts电路频率,可实现任意频谱结构的目标波形输出.该文结合设计实例给出了具体的设计步骤,并分析了设计性能,仿真结果表明该方法是有效可行的.

摘要：提出了基于连续混沌时间尺度变换的连续混沌调频信号动力学设计理论,并以Colpitts电路为例给出了具体的实现模型.通过吸引子重构和Lyapunov指数分析,阐述了连续混沌调频信号的动力学特性.结果显示连续混沌调频信号的最大Lyapunov指数与混沌信号的最大Lyapunov指数相同;连续混沌调频信号的动力学设计实现方式简单且系统参数易于控制,同时信号形式与数学意义上的连续混沌调频信号保持一致.

摘要：传统搜索引擎通常靠抓取全文关键词进行分析,由此带来三大缺陷:缺乏语义描述导致查准率低;检索结果冗余模糊导致检索效率低;检索途径不足.基于DC元数据描述网络资源的优越性,课题组设计了一个基于DC元数据的网络搜索引擎系统DCSE,力图克服传统搜索引擎的上述缺陷.DCSE系统自动抓取含DC描述的Web网页,把DC描述信息存入到数据库,排序索引后提供用户检索.检索界面设计成以15个DC元素为检索项的多项逻辑组合检索,检索结果以各DC元素的描述内容来显示,如标题、创建者、描述、日期等.用户通过多项组合检索提高查准率,并通过清晰的结果显示对所需信息做出快速判断、选择,从而达到提高检索效率的目的.

摘要：量子点发光二极管(QLEDs)具有色饱和度和色纯度高等优点,在照明与显示领域具有广泛应用前景,成为发光领域研究的热点之一。由于器件采用多层结构,表面和界面问题成为制约QLEDs发展的一个棘手问题。本文使用原子层沉积技术在氧化锌(ZnO)电子传输层和量子点(QDs)发光层之间插入不同厚度的二氧化钛(TiO_(2))薄层,对ZnO和QDs发光层之间的界面进行修饰。发现插入0.270 nm的TiO_(2)后,器件的漏电流降低约一个量级,激子的平均寿命从15.94 ns增加到16.61 ns,说明插入TiO_(2)修饰层可以有效降低QDs发光层中激子猝灭,从而提高器件在低驱动电压下的电流效率(约提高15%)。上述结果有望为QLEDs在照明和显示领域的产业化提供参考。

摘要：提出一种飞机座舱综合显示系统中基于现场可编程门阵列(FPGA)的2D图形硬件加速引擎设计方案,将图形分解为一系列基本的点和水平线输出。为避免图形加速引擎直接对SDRAM的零碎操作导致的存储器操作瓶颈,引入图形缓存机制,并根据图形像素的存储特点,提出远区域优先(FAF)图形缓存页面淘汰算法。讨论图形加速引擎内部各模块的逻辑结构及其逻辑设计,在对模块进行波形仿真的基础上,实现系统级仿真结果的可视化验证。仿真及实际应用结果表明,所提出的图形加速引擎提高了图形显示性能,满足当前飞机中对2D图形实时显示及飞控系统的可靠性要求。

摘要：基于改进的Euclid算法,提出了一种仅含两个折叠计算单元的结构,并用三级流水线结构整体实现以提高吞吐率.将常规有限域乘法器转化到复合域中实现,降低了芯片的复杂性和关键路径延迟.以RS(255,239)为例,基于TSMC 0.18标准单元库的译码器电路规模约为20 614门,在相同纠错能力下,该结构相比较于传统的并行脉动阵列结构,其硬件复杂度可减少60%左右.