The Stability of Rare Earth-Iron-Nitrides Sm_2(Fe,M)_(17)N_y,Permanent Magnets

The effects of the partial substitution of element M(M=Cr,V,Mn,x=0.05;Zr,Ga,x=0.017;Si,x=0.15;Co,x=0.10)for Fe in samarium-iron-nitride Sm_2(Fe_(1-x)M_x)_(17)N_y compounds on their stabilitiesand Curie temperatures have been studied.It is found that Co,Ga can raise the Curie temperature of thecompounds.The initial decomposition temperatures cannot be raised significantly by all the studied elementsexcept Co.The result contradicts the formation enthalpy consideration.The final decomposition tempera-tures can be raised by all of the substitution elements.The effects of atmospheres on their decomposition be-havior were also studied.The results show that oxidation is the major reason for magnetic deterioration ofthe powder heated in air.Compared with nitrogen atmosphere,argon or vacuum helps to delay the decompo-sition of the compounds.     

智能化红外焊缝检测仪的实时信号自相关分析

详细介绍了在改进红外焊缝检测仪的过程中实时信号的一种抗干扰方法－－自相关方法。重点离自相关方法的数学模型，软件框图及设计思想，并给出了实验结果。     

Rapid calculation of the periodic steady state for electronicallyswitched, time varying power system loads

The periodic steady state of power distribution system loads is studied for electronically switched, time varying cases. Many loads of this type appear on contemporary power systems as energy saving and controllable demands. Several alternative methods of calculating the periodic steady state are discussed and a new method is proposed based on the frequency modulation property of the discrete Fourier transform. The new method is termed the gain-shift formula (GSF) because the format of the technique entails adding frequency shifted terms which represent the parameter to be calculated. An example of a triac-switched load on the distribution system is given. The main advantages of the GSF are: rapid calculation of the periodic steady state; and efficient calculation of the frequency spectrum of voltages and currents in the periodic steady state     

Steady-state weights solution to affine projection algorithm

A new expression of the weights update equation for the affine projection algorithm (APA) is proposed that improves the convergence rate of an adaptive filter,particularly for highly colored input sign...     

Stability analysis and antiwindup design of uncertain discrete-time switched linear systems subject to actuator saturation

This paper investigates the stability analysis and antiwindup design problem for a class of discrete-time switched linear systems with time-varying norm-bounded uncertainties and saturating actuators by using the switched Lyapunov function approach.Supposing that a set of linear dynamic output controllers have been designed to stabilize the switched system without considering its input saturation,we design antiwindup compensation gains in order to enlarge the domain of attraction of the closed-loop system in the presence of saturation.Then,in terms of a sector condition,the antiwindup compensation gains which aim to maximize the estimation of domain of attraction of the closed-loop system are presented by solving a convex optimization problem with linear matrix inequality(LMI)constraints.A numerical example is given to demonstrate the effectiveness of the proposed design method.     

基于嵌入式移动浏览器的QtWebkit 2.1内核研究与开发

通过对多种支持HTML5技术内核的分析,选取了Webkit内核Qtwebkit2.1。在对其进行深入分析的基础上,着重研究了它对HTML5的支持。最后选取并裁剪了基于Qtwebkit2.1内核的浏览器QtWeb,实现对MeeGo平台的移植。经实验表明,该嵌入式移动浏览器能部分支持HTML5技术规范,为以后的进一步研究奠定了良好的基础。     

入侵检测在存储区域网中的应用

从SAN(存储区域网)的安全隐患出发,分析了SAN在应用环境中受到的三种典型威胁。结合现行的入侵检测技术给出一个可行的解决方案。     

基于C#的电子文档管理系统

鉴于工作中积累了各种各样的文件,数量多、存储分散,易造成文档查找困难等问题,设计了办公电子文档管理系统,实现了资料管理、资料查阅、用户管理、打印管理和系统管理功能。实用管理的功能保证了文档资料能够最大化实现其价值,作为科研人员有力的参考资料。