基于涡流技术的检测系统设计

以一种新型的管道爬行器系统为平台,研制出一套涡流检测系统.该系统基于脉冲涡流技术对油气管道腐蚀状况进行评价,从而在不拆卸管道包履层的前提下,探测管道的壁厚减薄区域.企业应用表明,该系统能够实现所要求的检测功能,打破了国外同类设备对中国市场的垄断.     

生活垃圾填埋场对地下水的污染研究

从分析河北省生活垃圾及其渗沥液化学成分入手,确定生活垃圾及其渗沥液的主要成分。通过实例,采用污染指数法,分析研究生活垃圾填埋场对地下水的污染情况,并总结河北省18个生活垃圾填埋场对地下水的污染规律。结果表明:生活垃圾填埋场总体上已对地下水造成了较严重污染,其污染程度因垃圾填埋场所处的地貌单元不同而有差别。     

新型中心波长稳定的高效率L波段掺铒光纤超荧光光源

采用后向抽运的两级级联的掺铒光纤超荧光光源的新型结构,运用同步抽运技术对两级光纤按比例进行后向抽运,从而实现高效率且中心波长稳定的L波段超荧光光源输出.研究了光纤总长度、两级光纤长度分配以及抽运比例对超荧光光源输出特性参数的影响.结果表明,通过采用两级级联后向结构可以将光谱从C波段有效地转移到L波段,而且能够实现在高抽运功率下具有中心波长对抽运功率波动不敏感的特性.在290 mW功率1:1抽运下,实验获得了输出功率97 mW,线宽47.3 nm,中心波长稳定的L波段超荧光光源.     

基于STC89C52单片机的荧光舞设计

本产品是由STC89C52单片机作为处理模块加载以程序控制的闪光带,通过各种形状的LED光带、程序控制和舞蹈表演的完美结合向观众呈现光与影的神奇表演-荧光舞的设计。详细介绍了系统的硬件设计和软件流程,其模块化设计使得系统设计及后期的改进更容易掌控。     

Real-time human blood pressure measurement based on laser self-mixing interferometry with extreme learning machine

In this paper, we present a method based on self-mixing interferometry combing extreme learning machine for real-time human blood pressure measurement. A signal processing method based on wavelet transform is applied to extract reversion point in the self-mixing interference signal, thus the pulse wave profile is successfully reconstructed. Considering the blood pressure values are intrinsically related to characteristic parameters of the pulse wave, 80 samples from the MIMIC-II database are used to train the extreme learning machine blood pressure model. In the experiment, 15 measured samples of pulse wave signal are used as the prediction sets. The results show that the errors of systolic and diastolic blood pressure are both within 5 mmHg compared with that by the Coriolis method.     

F-P标准具间距高精度测量

提出一种通过测量F-P标准具透射峰移动个数与F-P标准具入射角度改变的对应关系,从而求得F-P标准具间距的高精度测量方法。当角度测量精度为30″,光谱仪精度为2 GHz时,该方法测量F-P标准具间距的相对误差为4×10~(-4).     

基于单片机的微型飞行器高度计

介绍了一种新型微型飞行器高度计的设计技术,主要是利用微型数字压力传感器和PIC单片机串行通信,读取传感器中压力、温度值及补偿参数,用软件进行温度补偿和高度计算;经试验室测试,其相对高度误差<±3m。且该高度计具有体积小、重量轻、功耗低、工作可靠等特点。     

基于DSP的微型飞行器空速计

介绍了一种采用微差压传感器、微型放大器、微功耗数字信号处理器(DSP)设计的新型微型飞行器空速计。为了提高仪表低量程端测量精度,采用分段直线拟合法消除器件的非线性引起的误差;经实验室测试,空速在0~30m/s范围内,误差为±1.5m/s。且该空速计具有体积小、重量轻、功耗低、工作可靠等特点。     

120OKW防爆导热油电加热控制系统设计

根据1200KW防爆导热油电加热工艺要求,设计了一种基于PLC和触摸屏的控制系统,实现对导热油出口温度的控制,并具有完善保护和报警功能。该设备现场运行情况表明：控温精度较高,人机对话界面友好,功能全面,运行可靠,满足工艺要求。     

Laser self-mixing interferometer with scalable fringe precision based on phase multiplication algorithm

In this paper, we present a phase multiplication algorithm (PMA) to obtain scalable fringe precision in laser self-mixing interferometer under a weak feedback regime. Merely by applying the double angle formula on the self-mixing signal multiple times, the continuously improved fringe precision will be obtained. Theoretical analysis shows that the precision of the fringe could be improved to λ/2n+1. The validity of the proposed method is demonstrated by means of simulated SMI signals and confirmed by experiments under different amplitudes. A fringe precision of λ/128 at a sampling rate of 500 kS/s has been achieved after doing 6th the PMA. Finally, an amplitude of 50 nm has been proved to be measurable and the absolute error is 3.07 nm, which is within the theoretical error range. The proposed method for vibration measurement has the advantage of high accuracy and reliable without adding any additional optical elements in the optical path, thus it will play an important role in nanoscale measurement field.