物联网安全接入网关的设计与实现

文章通过分析物联网发展过程中存在的安全问题,提出了如何通过物联网安全接入网关,构建接入安全、管理可控的物联网系统架构,最后详细设计了物联网安全接入网关的功能组成和安全技术要求。     

基于井下环境的SIFT算法研究

针对煤矿环境中现有图像特征匹配算法不适用的问题,提出了新的特征匹配算法。该算法首先对图像进行Curvelet去噪预处理,然后采用SIFT进行特征向量的构建和匹配,通过RANSAC方法的优化改进去除误匹配点,通过建立投影变换模型实现图像的拼接。实验表明,该算法在噪声大、光照不均、模糊的复杂环境中有较好的鲁棒性,解决了煤矿环境中图像容易误匹配的现象,拼接效果平滑自然。     

RBF在冷轧在线监测与故障诊断中的应用

通过对某钢厂冷轧电气传动系统分析,合理选取检测信号,构建了基于组态的实时在线监测系统,实现实时数据显示、报警、样本数据的存储、数据采集、参数设定等功能。利用MATLAB的Simulink工具构建了冷轧传动中的三相异步电动机故障诊断仿真系统。将RBF神经网络技术应用于冷轧电气传动系统的故障诊断,设计了基于RBF网络的三相异步电动机故障诊断系统。通过对训练好的网络进行验证,证明所设计的诊断方法能够对传动系统中的电动机故障进行很好的预测和判断,具有良好的实际应用前景。     

基于投影直方图的文档图像快速匹配研究

如何实现文档图像间的快速匹配已成了人们日益关注的课题.针对文档图像的现有方法进行了研究,提出一种文档图像匹配的新方法.为进一步提高文档图像的匹配性能,结合用行列方向投影特征进行了文档图像的特征分析和提取工作.从而建立了特征相似匹配模t,在进行文档图像匹配时主要采用了平方差进行相似度度量和折半查找进行快速匹配的策略.实验表明随着二分法次数的增加,文档图像的相似度比较效率一定程度上得到很大的提高,匹配算法具有很好的杭倾斜和抗压缩效果.     

基于Lucene的全文检索系统的研究与实现

Lucene是一个优秀的开源全文搜索技术框架,Lucene全文检索技术是信息检索领域广泛使用的基本技术.它能非常方便地为各种应用程序加入全文索引和搜索功能,快速有效地索引企业累积的大量信息资源.文中阐述了建立全文检索系统的必要性,介绍了全文检索系统的概念并分析了Lucene的系统结构和实现机制,最后结合实际应用背景从系统设计、文挡抽取、索引的建立及执行检索等方面介绍了全文检索系统的实现过程.实践证明,该系统的查准率、查询速度等均达到了设计要求.     

Implementation and evaluation of parallel FFT on Engineering and Scientific Computation Accelerator (ESCA) architecture

The fast Fourier transform (FFT) is a fundamental kernel of many computation-intensive scientific applications.This paper deals with an implementation of the FFT on the accelerator system,a heterogeneous multi-core architecture to accelerate computation-intensive parallel computing in scientific and engineering applications.The Engineering and Scientific Computation Accelerator (ESCA) consists of a control unit and a single instruction multiple data (SIMD) processing element (PE) array,in which PEs communicate with each other via a hierarchical two-level network-on-chip (NoC) with high bandwidth and low latency.We exploit the architecture features of ESCA to implement a parallel FFT algorithm efficiently.Experimental results show that both the proposed parallel FFT algorithm and the ESCA architecture are scalable.The 16-bit fixed-point parallel FFT performance of ESCA is compared with a published work to prove the superiority of the mapping algorithm and the hardware architecture.The floating-point parallel FFT performances of ESCA are evaluated and compared with those of the IBM Cell processor and GPU to demonstrate the computing power of the ESCA system for high performance applications.     

基于CORDIC算法的高速正余弦函数实现架构

坐标旋转数字计算机算法（Coordinates Rotation Digital Computer （CORDIC） Algorithm）,其硬件结构实现简单,可以在硬件系统中实现包括乘、除、各种三角函数、自然对数和平方根在内的初等函数;针对图像处理对计算速度要求高的特点,本文采用了多级流水线的实现架构,可以明显提高CORDIC电路的工作频率;为了进一步地减少各级流水线的计算时延,电路中采用了运算速度较快的BKA加法器。基于Altera公司的FPGA（EP2C5F256C7）芯片的CORDIC算法架构综合,使其能够工作在188．38MHz的最高时钟频率。仿真结果表明本文提出的CORDIC架构能高速正确地实现CORDIC算法。     

The Design with Intent Method: A design tool for influencing user behaviour

Using product and system design to influence user behaviour offers potential for improving performance and reducing user error, yet little guidance is available at the concept generation stage for design teams briefed with influencing user behaviour. This article presents the Design with Intent Method, an innovation tool for designers working in this area, illustrated via application to an everyday human-technology interaction problem: reducing the likelihood of a customer leaving his or her card in an automatic teller machine. The example application results in a range of feasible design concepts which are comparable to existing developments in ATM design, demonstrating that the method has potential for development and application as part of a user-centred design process.     

3G SFP光发射模块设计原理与性能研究

介绍光发射模块的原理、主要光器件的选择以及设计时所要满足的性能指标,针对主要的两个性能指标平均光功率和消光比进行了研究。测试结果表明,该光发射模块满足平均光功率和消光比的要求,并且可以传输2．97 Gbps pathological信号。     

Three heuristic procedures for the stochastic,two-machine flow shop problem

Although the deterministic flow shop model is one of the most widely studied problems in scheduling theory, its stochastic analog has remained a challenge. No computationally efficient optimization procedure exists even for the general two-machine version. In this paper, we describe three heuristic procedures for the stochastic, two-machine flow shop problem and report on computational experiments that compare their effectiveness. We focus on heuristic procedures that can be adapted for dispatching without the need for computer simulation or computer-based search. We find that all three procedures are capable of quickly generating solutions close to the best known sequences, which were obtained by extensive search.