基于STL文件的Laplacian网格优化算法

针对直接重构得到且以STL文件格式存储的网格模型质量不高的问题, 提出了一种基于Laplacian坐标的网格模型全局优化算法。该算法在提高三角面片质量的同时可以很好地保持原网格模型的局部几何特征, 其核心思想是通过在最小二乘意义下求解由权重控制的包含顶点位置和拉普拉斯坐标双重约束的线性系统来对网格顶点进行重新定位。从实验结果可以看出, 该算法较以往的Lapacian优化算法在对网格细节特征的保持上有一定优势。     

LTE小区搜索中一种新的SSS检测算法

主要研究了SSS检测, 提出一种新的SSS检测算法。该算法首先利用滑动平均窗修正接收的PSS处估计出的信道频率响应, 并用修正后的信道频率响应对接收的SSS序列进行信道补偿; 其次, 算法对信道补偿后的序列进行实数提取操作, 消除虚部数据干扰; 最后算法联合两个连续的SSS接收序列进行检测进一步提高检测性能。TDD和FFD两种模式下的仿真结果表明：该算法可以较好地实现SSS检测且比现有几种SSS检测算法在低信噪比（SNR<0 dB）条件下具有更好的检测性能。     

计算机网络安全与防护技术研究

本文主要对计算机网络安全产生的根源和存在的风险进行了初步分析,对目前常用的网络安全技术进行了较为深入的研究,并阐述了防火墙技术与入侵检测技术在计算机网路中联合部署的方法和步骤.     

计算机数据文件安全防范措施探讨

在计算机数据文件安全问题方面,有着相当一部分问题都是由于计算机操作人员安全意识不高、计算机安全操作制度不完善等原因引起的。本文对于计算机数据文件安全问题的重要性进行了分析,并且阐述了计算机数据文件安全方法措施。     

基于BT技术的局域网文件传输

随着网络技术的不断发展,网络传输的速度越来越快,随之文件的体积也就越来越大,如果局域网内部还是采用传统的HTTP或FTP进行文件传输,就会对服务器性能要求越来越高,这种模式已经不能满足大规模的文件分享和传输,本文设计了基于BT技术的局域网文件传输模型。     

Synchronization in heterogeneous networks of discrete‐time introspective right‐invertible agents

This paper studies output synchronization problem, formation problem, and regulated synchronization problem for a heterogenous network of discrete‐time introspective right‐invertible agents. We first propose a decentralized control scheme to solve the output synchronization problem for a set of communication topologies. Moreover, if the synchronization trajectories are assumed to be bounded, a universal controller can be constructed for all communication topologies, which contain a directed spanning tree. The design can be applied to solve the formation problem with arbitrary formation vectors. In the regulated synchronization problem, we assume only the root receives information from exosystem. We then design a decentralized controller to solve the problem for a set of communication topologies. Copyright © 2013 John Wiley & Sons, Ltd.     

银企互联中对账文件动态生成机制

针对银企互联中格式多样的对账文件,该文提出了两种动态文件生成机制。一种是基于结构体的动态文件生成机制,它利用了C语言中的结构体成员内存连续的原理,适用于对账明细数据源表固定的情况,但不适合多数据表的联合处理。另外一种是与动态SQL结合的文件生成机制,该机制不再局限于同一个数据源表,可以多表联合查询处理,同时又具备文件格式灵活配置的优点,适应范围更广,灵活度更高。     

A general method for modified function projective synchronization

This paper investigates the modified function projective synchronization,which means that the drive system and the response system are synchronized up to a desired scale matrix of function. By the active control scheme,a general method for modified function projective synchronization is proposed. Numerical simulations on chaotic Rssler system and hyper-chaotic Chen system are presented to verify the effectiveness of the proposed scheme.     

OFDM系统相关矩阵的分块结构及同步算法

根据载波加权可增强OFDM系统周期平稳性,实现系统盲同步的基本原理,分析了OFDM系统相关矩阵的分块结构,给出相应系统的盲同步算法.该方法通过检测相关矩阵的分块Toep litz矩阵结构,实现系统定时和载频偏差的估计.同时,在特定系统同步性能交换误码率的情况下通过分析载波加权、系统误码率和载频同步误差之间的互相制约关系,进一步给出了载波加权的确定方法.实验仿真结果表明,采用分块相关矩阵的同步方案与采用循环谱的同步方案相比,可获得更好的系统载频和定时同步效果.     

Synchronization and channel estimation for MIMO OFDM wireless LAN systems

A new preamble structure is designed for wireless LAN based on MIMO OFDM systems, which can be used for both synchronization and channel estimation. Modulatable orthogonal polyphase sequence is utilized in training symbol design regarding its correlation properties. The time synchronization and channel estimation are achieved by measuring the correlation between the received training sequence and the locally generated training sequence. Repeated training symbols are used to get carrier frequency offset (CFO) estimation. It is shown from the analysis that the accuracy of frequency synchronization is close to the Cramér-Rao lower bound. The training sequences are optimal for channel estimation based on the minimum mean square error (MMSE).