Modeling NOx emissions from coal-fired utility boilers using support vector regression with ant colony optimization

Modeling NO_x emissions from coal fired utility boiler is critical to develop a predictive emissions monitoring system (PEMS) and to implement combustion optimization software package for low NO_x combustion. This paper presents an efficient NO_x emissions model based on support vector regression (SVR), and compares its performance with traditional modeling techniques, i.e., back propagation (BPNN) and generalized regression (GRNN) neural networks. A large number of NO_x emissions data from an actual power plant, was employed to train and validate the SVR model as well as two neural networks models. Moreover, an ant colony optimization (ACO) based technique was proposed to select the generalization parameter C and Gaussian kernel parameter γ. The focus is on the predictive accuracy and time response characteristics of the SVR model. Results show that ACO optimization algorithm can automatically obtain the optimal parameters, C and γ, of the SVR model with very high predictive accuracy. The predicted NO_x emissions from the SVR model, by comparing with the BPNN model, were in good agreement with those measured, and were comparable to those estimated from the GRNN model. Time response of establishing the optimum SVR model was in scale of minutes, which is suitable for on-line and real-time modeling NO_x emissions from coal-fired utility boilers.     

无线传感器网络在风力发电中的应用研究

为解决风力发电场中现有测控方法存在的成本高、维护难等问题,通过对无线传感器网络和风力发电场特点进行研究,设计了一种基于无线传感器网络的传输平台.该平台使用基于ZigBee技术的CC2420芯片进行数据传输,并利用OPNET软件对其网络传输特性进行网络仿真.仿真结果有力地证明了无线传感器网络应用于风力发电场的可行性,该网络平台能够很好地完成风力发电场的数据检测和数据传输任务.     

A study of the optimal measurement placement for parameter identification of orthotropic composites by the boundary element method

This paper concentrates on the design of the optimal measurement placement for the parameter identification of two-dimensional orthotropic composites, which is modeled by the boundary element. From the analysis of the well-posedness of the parameter identification processes using the Levenberg–Marquardt method, a performance indicator and an estimation of the maximum bias of identified parameters are deduced. Based on these results, a method for selecting the optimal measurement placement is proposed. The validity of this method is illustrated by some numerical examples. These examples reveal that the measurement placement has significant influence on identification results. Furthermore, an iterative process of selecting measurement placement is suggested for practical implementation.     

南京长江第四大桥航行条件数值模拟研究

结合二维水流数学模型和船舶运动数学模型,研究了拟建南京长江第四大桥对通航水流条件的影响,分析了桥墩周围的水流条件变化,模拟了船队在建桥前后通过桥区河段的航迹线,得到了航行过程中的航行参数,综合分析认为南京四桥修建对通航水流条件影响很小,对船舶航行也无明显影响。     

PNX0101及其在便携式MP3播放器中的应用

目前,便携式MP3播放器的发展十分迅速。用户对便携式MP3播放器的音质、体积、功耗等方面提出了越来越高的要求。Philips公司推出的32位ARM+DSP双核结构的PNX0101芯片因其一流的音质表现、更小的尺寸、更小的功耗等特点成为解码芯片领域的热点。本文介绍了PNX0101的结构和特点,分析了它具有竞争力的优异性能,并对基于PNX0101设计的便携式MP3播放器及其电源管理进行了讨论。     

TMS320F206与TLC320AD50C接口电路的设计

介绍了TI公司数字信号处理器TMS320F206的同步串行接口的特点，及∑-△型A／D、D／A转换芯片TLC320AD50C的结构和通信方式，详细叙述了两者的接口电路、软件设计方法。     

基于LabWindows/CVI的计算机图形动态模拟技术

计算机图形动态模拟是动态测试CAT系统的重要组成部分，本文提出了利用Labwindows/CVI实现动态模拟的基本原理与方法，并给出了拖拉机动态测试系统中仿真控制的实例，动态模拟功能设计成为相对独立的模块，有利于实现测试系统的自动化监控和操纵。     

用层次分析法安排电力系统事故后火电机组恢复的次序

在电力系统事故恢复过程中，火电机组的恢复复次序对电力系统的恢复有重大影响本文在分析了影响火电机组恢复及出力的各种因素后，将定性与定量分析方法组合，建立了火电机组恢复的层次模型，最后给出了算例。     

汽气共生热电气联产技术的研究

本文介绍了一种汽气共生热电气三联产新工艺．该工艺是以现有循环流化床技术为基础，集燃烧和气化工艺于一体，能同时产生民用煤气、蒸汽、电力．在小型热态试验以架上进行的一系列试验已成功地证实了该技术的可行性．在此基础上，一台蒸汽产量为７５ｔ／ｈ的热电气三联产装置已完成设计，正在实施之中．