A numerical model for induction heating processes coupling electromagnetism and thermomechanics

This paper presents a mathematical and numerical model developed for coupling the various physical phenomena (electromagnetic, thermal and mechanical) taking place in axisymmetrical induction heating processes. All three electromagnetic, thermal and mechanical models are time dependent and take full account of the electromagnetic and thermal non‐linear effect especially with magnetic materials. The electromagnetic problem is discretized and solved in the workpiece, air and inductors. The heat transfer equation and the mechanical equilibrium equations are solved in the workpiece only, both using a finite element method. The mechanical model can take into account thermoelastic–plastic behaviour for the part. The model has been successfully applied to several cases of induction heating. Comparisons between numerical and experimental results show an excellent agreement. Copyright © 2003 John Wiley & Sons, Ltd.     

FAFFA加速的PO-MM研究复杂金属载体上线天线电磁特性

本文提出了一种快速远场近似(FAFFA)加速的混合物理光学矩量法(POMM),利用FAFFA加速计算矩阵方程中的矩阵矢量积,明显提高了计算效率.对物体表面上的远场组之间的耦合作用推导出了一组简洁的计算公式,并分析了计算复杂度.复杂金属组合体上线天线输入导纳、互导纳和方向性图的计算结果与文献结果一致.利用该方法分析计算了一个舰船模型上线天线的电磁特性.数值结果表明了这种方法的正确性和工程应用中的有效性.     

降低雷达接收机中噪声的几种方法

噪声是影响雷达接收机灵敏度的重要因素。本文通过讨论雷达接收机噪声的来源，分析并提出了集中降低雷达接收机内部和外部噪声的几种方法，具有一定的实际意义。     

Mixture of probability distributions as a basic component in simulating measurement accuracy

A stochastic model is proposed for a basic mechanism in the formation of uncertainties in physical quantity measurements. __________ Translated from Izmeritel'naya Tekhnika, No. 1, pp. 12–17, January, 2006.     

基于参考模型的自适应话音处理

本文讨论了一种带有参考通道的自适应话音消噪滤波器原理，该滤波器采用最小均方差(心幅)算法。将此滤波器应用于复杂噪音背景的话音信号提取，能很好地抑制背景噪声，从而获得清晰的话音信号。     

Interconnected power systems with superconducting magnetic energy storage

The objective of this work is to discuss the concept of back‐to‐back interconnection systems with energy storage, especially with a Superconducting Magnetic Energy Storage (SMES) incorporated into a back‐to‐back DC link. In this case, each converter of the back‐to‐back system is used as a power conditioning system for the SMES coils. Since the AC–DC converter can be designed independently of the frequency of the power system, a two‐way switch is connected to the AC side of each converter. This two‐way switch can select the interconnected power systems. By using the two‐way switches, this system can provide the stored energy in the SMES system to each interconnected power system through two AC–DC converters. For instance, lower‐cost power of each power network can be stored through two converters during the off‐peak hours and made available for dispatch to each power network during periods of demand peak. Then this system increases the reliability of electric power networks and enables the economical operations depending on the power demand. This paper describes the unique operations of the back‐to‐back interconnection with SMES and discuses the optimal SMES configuration for a 300‐MW‐class back‐to‐back interconnection. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 164(2): 37–43, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20482     

USL和USK系列振动筛防噪技术分析

为了改善筛分机械的使用环境，降低筛分机械的噪声，从噪声源入手，从内因和外因两个方面分析了筛分机噪声的形成原因。论述了USL和USK系列振动筛在降低噪声方面所采取的先进技术措施。     

奇异值分解压制随机噪声的方法及应用

针对随机噪声压制问题，通过对多项式确定的同相轴形状重新选取数据矩阵，再对新选取的数据矩阵进行SVD滤波，从而压制随机噪声。通过对矩阵奇异值分解的研究，揭示了奇异值分解的原理和SVD滤波原理，将一个多道地震记录看作一个图，它可分解为由一系列正交的子图，通过对子图适当选择并结合其它手段，从而达到提高信噪比的目的，为奇异值分解在地球物理中的进一步应用提供了理论依据。实际数据应用表明，该方法去噪手段灵活、保真性好、分辨率高，对一些突然的脉冲干扰、侧反射、以及其他的反向干扰有明显效果。     

自适应相干噪声衰减技术

去除噪声是必需的地震数据处理过程。由于地表条件和地震波激发、传播以及接收条件等诸多方面的原因，时常引起地震记录上出现各种相干干扰波。本文主要针对地震数据处理中地震剖面上存在的各种相干噪声，提出了时问一空间域自适应相干噪声衰减技术，以进行信噪分离。这种方法把噪声在整个处理平面上的视速度近似看作常量(正值或负值)，可以有效地消除地震剖面上的线性噪声、面波以及多次波等，并且对信号的保真度高。本文方法是复杂地区低信噪比地震数据处理的一种理想的噪声去除方法，具有运算速度快、压制噪声效果好等优点。     

单片机在产生特殊复合磁场系统中的应用

探讨了在电磁铸轧中采用单片机作为核心监控装置的工作原理，论述了用单片机实现函数信号发生的硬件设计和软件流程，实现了对感应器产生特殊复合磁场的控制，并提出了一种新的随机数的产生方法。