基于椭圆曲线密码体制的可认证的密钥协商设计与分析

椭圆曲线密码体制以其密钥短、安全强度高、速度快等优越性被广泛用于进行构建数字签名和用户身份认证方案.同样,它也可以用来构建密钥交换协议.Diffie-Hellman密钥协商协议对来自中间人的攻击是脆弱的.基于椭圆曲线离散对数难解性, 利用椭圆曲线密码体制的数字签名方案,提出了基于身份认证的密钥协商协议.该协议提供身份认证、密钥确认、完美前向安全性, 并能够防止中间人攻击.     

一类简单闭域的包含测试算法设计

自由曲面的高斯图计算中,需要对由抛物线和直线段组成的闭域进行包含检测来判断该闭域是否为最小闭域,抛物线段由逼近折线多边形表示且单调。基于点与简单闭域的拓扑关系,重新定义了“穿越边界”,设计了点与简单闭域关系判断的算法。该算法通过检测穿越闭域边界次数的奇偶性来判断点与闭域的位置关系;其中对射线与抛物线相交的处理大大减少了判断次数。可以证明算法的时间复杂度仅为o(n);实验表明,该算法简单有效可靠。     

实时监测系统中SNMP报文分析算法的实现

简单网络管理协议帮助网络管理员实现对基于TCP/IP网络的分布式系统的有效管理。管理员在本地计算机上(通常是一个工作站)使用“取—存”模式完成对代理的各种控制,而代理通过对SNMP报文的分析将通信原语转换成等价的在本地数据结构上的操作。本文从SNMP基本体系结构入手,提出了一种基于VisualC 的实时监测系统中SNMP报文分析算法的实现。     

Assistant force compensation for hand movement of patients by using exogenous signals and/or neurophysiological signals

Because functional diseases of the brain can cause disabilities related to human movement control, a compensation method was developed for improving the performance of hand movements. The compensation for human hand movements can be carried out by adding an assistant force that is generated from artificial equipment attached to a human arm. From the experiment on visual target tracking, it was found that the tracking trajectory was adequately represented by a dynamic model of the motion of an articulated industrial robot arm, and the different abilities for movement control among healthy people and patients were classified by different model parameters as position loop gain, velocity loop gain, and response delay. Dynamic force compensation was approached by considering the different control features of the patients. The effectiveness of the proposed compensation method was verified in a simulation study on an actual industrial robot arm. A human-machine interface, e.g., a brain-computer interface (BCI), for realizing the control of artificial equipment to compensate for human hand movements is also presented and discussed.     

Finite‐time formation control of multiple nonholonomic mobile robots

This paper considers finite‐time formation control problem for a group of nonholonomic mobile robots. The desired formation trajectory is represented by a virtual dynamic leader whose states are available to only a subset of the followers and the followers have only local interaction. First of all, a continuous distributed finite‐time observer is proposed for each follower to estimate the leader's states in a finite time. Then, a continuous distributed cooperative finite‐time tracking control law is designed for each mobile robot. Rigorous proof shows that the group of mobile robots converge to the desired geometric formation pattern in finite time. At the same time, all the robots can track the desired formation trajectory in finite time. Simulation example illustrates the effectiveness of our method. Copyright © 2012 John Wiley & Sons, Ltd.     

编码电缆定位技术和无线扩频通信技术在焦炉四大车自动化系统中的应用

阐述攀钢煤化工厂新1#、2#焦炉四大车自动化系统应用情况,并对编码电缆定位技术和无线扩频通信技术进行了分析与论述。     

High-Q microresonators on 4H-silicon-carbide-oninsulator platform for nonlinear photonics

The realization of high-quality (Q) resonators regardless of the underpinning material platforms has been a ceaseless pursuit, because the high-Q resonators pro...     

基于粗粒度数据流架构的稀疏卷积神经网络加速

卷积神经网络(convolutional neural network, CNN)在图像处理、语音识别、自然语言处理等领域实现了很好的性能.大规模的神经网络模型通常遭遇计算、存储等资源限制,稀疏神经网络的出现有效地缓解了对计算和存储的需求.尽管现有的领域专用加速器能够有效处理稀疏网络,它们通过算法和结构的紧耦合实现高能效,却丧失了结构的灵活性.粗粒度数据流架构通过灵活的指令调度可以实现不同的神经网络应用.基于该架构,密集卷积规则的计算特性使不同通道共享相同的一套指令执行,然而稀疏网络中存在权值稀疏,使得这些指令中存在0值相关的无效指令,而现有的指令执行方式无法自动跳过它们从而产生无效计算.同时在执行不规则的稀疏网络时,现有的指令映射方法造成了计算阵列的负载不均衡.这些问题阻碍了稀疏网络性能的提升.基于不同通道共享一套指令的前提下,根据稀疏网络的数据和指令特征增加指令控制单元实现权值数据中0值相关指令的检测和跳过,同时使用负载均衡的指令映射算法解决稀疏网络中指令执行不均衡问题.实验表明：与密集网络相比稀疏网络实现了平均1.55倍的性能提升和63.77%的能耗减少.同时比GPU(cuSparse)和Cambricon-X实现的稀疏网络分别快2.39倍(Alexnet)、2.28倍(VGG16)和1.14倍(Alexnet)、1.23倍(VGG16).     

基于几何-语义联合约束的动态环境视觉SLAM算法

传统视觉同步定位和地图构建（Simultaneous localization and mapping, SLAM）算法建立在静态环境假设的基础之上,当场景中出现动态物体时,会影响系统稳定性,造成位姿估计精度下降。现有方法大多基于概率统计和几何约束来减轻少量动态物体对视觉SLAM系统的影响,但是当场景中动态物体较多时,这些方法失效。针对这一问题,本文提出了一种将动态视觉SLAM算法与多目标跟踪算法相结合的方法。首先采用实例语义分割网络,结合几何约束,在有效地分离静态特征点和动态特征点的同时,进一步实现多目标跟踪,改善跟踪结果,并能够获得运动物体的轨迹和速度矢量信息,从而能够更好地为机器人自主导航提供决策信息。在KITTI数据集上的实验表明,该算法在动态场景中相较ORB-SLAM2算法精度提高了28%。     

钢筋混凝土框架结构施工技术

对多层框架结构施工过程中遇到的技术问题及解决方案进行论述,对做好类似工程的施工技术工作具有借鉴意义。