一种混沌信号去噪方法的研究

以Takens嵌入定理和影子定理为理论依据，提出一种能对混沌信号去噪的局部投影方法。该方法不需潜在动力学系统的先验知识，符合工程实用的要求。通过实验结果表明这种方法对混沌信号去噪很有效。     

精密扇形扫描稳速控制

在扇形扫描中，马达稳速的控制是通过相位补偿实现的。本文提出一种新的稳速控制方法、相位补偿控制，并介绍了相位补偿电路的设计。     

受干扰波相位测量的一种新方法

为了测量受噪声和谐波干扰的两个信号间的相位差，基于自适应带通滤波器（ABF）和测量信道交换技术，提出了一种新的测量方法。ABF采用可编程开关电容滤波器（PSCF）和锁相环，明显地抑制了噪声和谐波干扰，频率跟踪范围超过四个倍频程（0．5Hz-6kHz）。用微处理器控制4个开关来交换测量信道，可以基本上消除测量通道引入的附加相位移。两种方法结合提高了相位差的测量精度。实验说明了该测量方法的有效性，该方法也适合于被测信号为慢时变情况。     

中频数字化及数字式正交解调

本文介绍用数字式下变频法实现中频正交解调的基本原理及主要性能。     

Impurity Distribution Behavior in Caprolactam Extraction with Environmentally Benign Mixed Solvents

In a previous study a solvent mixture of heptane containing 40 mass % heptanol was selected as an alternative in the industrial extraction of caprolactam to replace benzene, toluene, or chlorinated hydrocarbons. This work reports the equilibrium distribution ratio of caprolactam and four model impurities of organic nature, namely, cyclohexanone, aniline, n‐methylcaprolactam, and cyclohexane‐carboxamide, comparing the mixed solvents with toluene as a reference. The resulting phase equilibria were interpreted using the equilibrium stage model. Based on these calculations it was found that, compared to toluene, the co‐extracted fraction of cyclohexanone and aniline was higher, that of n‐methylcaprolactam was comparable, and that of cyclohexane‐carboxamide was lower using the mixed solvent. Overall, the mixed solvent reduced the fraction of co‐extracted impurities by almost 10 %.     

Studies on the corrosion behavior of cerium-implanted zircaloy-4 with GAXRD

In order to study the influence of cerium ion implantation on the aqueous corrosion behavior of zircaloy-4, specimens were implanted by cerium ions with a fluence range from 1×10¹⁶ to 1×10¹⁷ ions/cm² at maximum 150°C, using MEVVA source at an extracted voltage of 40 kV. The valence and elements penetration distribution of the surface layer were analyzed by X-ray photoelectron spectroscopy (XPS) and auger electron spectroscopy (AES) respectively. Glancing angle X-ray diffraction (GAXRD) was employed to examine the phase transformation due to the cerium ion implantation in the oxide films. Three-sweep potentiodynamic polarization measurement was employed to value the aqueous corrosion resistance of zircaloy-4 in a 1 N H₂SO₄ solution. It was found that a significant improvement in the aqueous corrosion behavior of zircaloy-4 implanted with cerium ions compared with that of the as-received zircaloy-4. The improvement effect will declined with raising the implantation fluence. The bigger is the fluence, the less is the improvement. Finally, the mechanism of the corrosion behavior of the cerium-implanted zircaloy-4 is discussed.     

Procedure for Measuring Low Concentrations of H2 and H2S Above a Water Surface

A simple measuring procedure for low concentrations of H₂ and H₂S (at the level of ppm fractions) above the surface of water by using sensitive gas analyzers is suggested. The procedure is easily accomplished in conditions outside the laboratory (under field conditions).     

单线复用技术在水文巡测设备中的应用

为了解决水文巡测设备中数据传输的可靠性，电力载波通讯中的单频阻波器技术被应用到巡测设备上。此法简单易行，稳定可靠。     

TCA785移相控制芯片应用方法的改进

TCA785是德国西门子公司生产的一种性能优秀的移相控制芯片 ,该器件具有温度适应范围宽 ,对过零点的识别更加可靠 ,输出脉冲的整齐度更好 ,移相范围更宽等优点 ,此外 ,由于TCA785的输出脉冲宽度可以手动自由调节 ,因此 ,该器件可广泛应用在晶闸管控制系统中。文章根据TCA785芯片的使用特点以及在逆变器实际运用中可能出现的一些问题 ,提出了一种改进的设计方法     

汽车摩擦片厚度测量装置驱动电路的研究

本文通过对摩擦片厚度在线测量装置系统构成的全面分析，对其驱动电路子系统进行了理论探索和技术研究，完成了相应的电路设计、误差分析及器件选择等工作，并进行了具体的实验验证，证明该驱动电路具有良好的性能，可圆满实现摩擦片厚度在线检测和实时分析的工作任务。