格宾生态网在太平港河道整治工程中的运用

随着生态水利的发展,自然和谐观念的加强,常规堤防防护结构难以满足要求。格宾生态网是一种既可保护河岸、加固堤防,又可改善和维持水生态环境的生态形式防护工程。通过格宾生态网在丽水太平港河道整治工程区地层情况因地制宜,就地取材,兼有防护与环境保护两方面的功效的实例介绍,为同类工程提供相关经验。     

安徽网厂调度生产网络组网方案研究与实施

近年来安徽电力工业发展迅速,电网规模不断扩大,安徽省调与各发电厂间的信息传输和数据交换日益增多,网厂间原有的专线互联方式已不能满足现有业务需求。针对这一问题,本文提出了安徽网厂间调度生产网络组网和实施方案,保证网厂间信息传输畅通和电网的安全稳定运行。     

互信息与爬山法相结合的贝叶斯网络结构学习

针对爬山法容易陷入局部最优,而随机重复爬山法时间开销过大的问题,将互信息与爬山法相结合,提出了MI&HC贝叶斯网络结构学习算法。首先利用互信息构建初始网络结构,再从该网络结构开始利用爬山法进行贝叶斯网络结构学习。仿真结果表明:MI&HC算法,对小型稀疏网络结构的学习效果非常好,对较大型的网络结构的学习也能得到令人满意的结果;该算法不需要节点顺序这一先验信息,却能获得与K2算法相当的学习效果。     

Decentralized fault detection and diagnosis via sparse PCA based decomposition and Maximum Entropy decision fusion

This paper proposes an approach for decentralized fault detection and diagnosis in process monitoring sensor networks. The sensor network is decomposed into multiple, potentially overlapping, blocks using the Sparse Principal Component Analysis algorithm. Local predictions are generated at each block using Support Vector Machine classifiers. The local predictions are then fused via a Maximum Entropy algorithm. Empirical studies on the benchmark Tennessee Eastman Process data demonstrated that the proposed decentralized approach achieves accuracy comparable to that of the fully centralized approach, while offering benefits in terms of fault tolerance, reusability, and scalability.     

A hybrid model-based optimal control method for nonlinear systems using simultaneous dynamic optimization strategies

To improve the overall control performance of nonlinear systems, an optimal control method, based on the framework of hybrid systems, is proposed. Firstly, the nonlinear systems are approximated by a number of piecewise affine models which are produced by the nonlinear systems at the specified operating points, then the piecewise affine models are synthesized under the framework of hybrid systems, and an associated optimal control problem, in which decision variables involve not only admissible continuous control but also the scheduling of subsystem modes, is established. Secondly, the optimal control problem is transformed into a MIQP problem by discretization over the whole state space and admissible control space to obtain the numerical optimal solution. For speeding up the algorithm, the simultaneous method on finite elements is used to lower the dimensions of the MIQP problem. Consequently, a hybrid model-based MPC for nonlinear systems is designed, and the adverse effects of model mismatch resulted from simultaneous method is weakened by MPC strategy. Simulations and comparisons with soft-switching method, hard-switching method and MLD method, confirm that a satisfactory performance can be obtained using the presented approach.     

PID control performance assessment using iterative convex programming

Minimum achievable output variance (MAOV) is a common benchmark for control performance assessment. Finding the MAOV of proportional–integral–derivative (PID) control systems is computationally expensive due to the inherent non-convexity of the associated optimization problem. We present in this paper a new framework for computing the MAOV of PID control systems. The problem of estimating the MAOV of a PID control system is novelly formulated as a convex program with an additional non-convex constraint. The non-convex constraint is linearized and handled by the penalty approach. Based on this, a low-complexity algorithm, which relies on the iterative convex programming technique, is developed to solve the MAOV problem. The new algorithm is proved to be convergent. We show via numerical examples that the new approach yields close-to-optimal solutions that are better than (or as good as) the solutions generated by the existing methods.     

单片机实现海明码纠错原理的研究

介绍了海明码的编码、解码、纠错原理及其构造方法,并将纠错原理应用于单片机之间的串行通信.阐述了发送机发送程序与接收机接收程序的流程,以及单片机实现海明码软件编码、解码的具体过程,并给出了找出一位差错并进行纠正的方法.该方法用于单片机遥测和遥控系统,具有高性价比、高可靠和操作简便的优点.     

支持可变功耗的多通道串行链路管理机制

互连网络是并行计算机、存储系统和各种数据中心的重要组成部分.随着网络带宽和系统规模的增加,互连网络需要的功耗也随之提升,而且在全系统中所占比例已不容忽视.提出了一种高速串行链路管理机制,根据网络中数据流量的变化,动态调整链路中使用的通道数量.但是即使链路空闲也不会关闭该链路中的所有通道,因此在降低功耗时不会改变网络的连接关系和拓扑结构.实验结果表明,这种机制可以大大增加互连的灵活性,在提供高带宽的同时降低互连网络在空闲时的功耗,缺点是启动延迟会稍有增加.     

用DSP实现基于VQ的说话人识别系统

在TI的DSK5402平台上构建了一个主要采用VQ方法的6个说话人识别系统。该系统采用了10阶的线性预测参数、10阶的线性预测倒谱参数及基音参数,提出了一种改进的LBG算法,以避免在迭代过程中产生空胞腔,使之能适应多种距离测量。实验证明,本系统在指定文本的说话人闭集测试中取得了满意的效果。     

基于草绘辅助3D动画综述*

提高3D动画的制作效率是发展3D动画的一个关键问题,随着计算机硬件技术和辅助技术飞速发展,为解决这一问题提供了可能。基于草绘交互方式的辅助技术正受到相关研究者的关注。简要地回顾了基于草绘辅助技术的研究现状和发展历程,总结分析了其在3D动画制作中各环节的辅助技术,并对今后的发展方向进行了展望。