低压变频器中的温升及其试验方法

低压变频器（交流进线l000V以下）越来越广泛的深入到人们的生活和生产中，我们正确认识及使用变频器，尤其是其工作环境以及散热问题，对变频器的可靠性的影响是非常大的。本文分析了变频器发热的主要原因，并重点介绍了变频器的温升重点部位及试验方法，以利于变频器用户掌握了解变频器温升及温升试验。     

黑龙江移动GSM网络交换设备搬迁建设方案探讨

着重论述了在全网交换设备搬迁过程中，对交换及配套传输工程所采取的关键技术、建设思路、建设方案、阶段安排以及流程分析等，并详细探讨了在搬迁中遇见的问题及解决方案。     

高功率脉冲氙灯的动态PSpice模型研究

根据气体放电相关理论建立高功率脉冲氙灯仿真模型,阐述了放电回路设计的基本原理,采用建立的模型通过计算机对TIL及NIF装置进行仿真,给出了放电回路的仿真结果,与装置运行实际数据比较发现仿真模型及过程可靠,为高功率激光装置的电子计算机辅助设计和分析提供了一种新途径。     

MIMO-OFDM系统Turbo接收机中的限幅非线性失真迭代对消法

在多入多出的正交频分复用系统中,常采用Turbo接收以保证系统性能。在正交频分复用系统中,限幅技术是常见的峰值平均功率比抑制技术,但限幅带来的非线性失真会造成带内失真和带外辐射,从而恶化系统性能。本文提出可以利用Turho接收机的先验信息进行限幅非线性失真的迭代对消,从而在引入少量复杂度的基础上,对抗限幅带来的影响。仿真结果表明,引入限幅非线性失真迭代对消算法可以有效提高系统性能,限幅门限越低效果越明显。     

GaAs/AlGaAs量子阱红外探测器噪声特性分析

分析了第一激发态在势垒以上的ＧａＡｓ／ＡｌＧａＡｓ量子阱红外探测器中存在的几种基本噪声,讨论了它们对探测器性能的影响。     

深亚微米低压CMOS IC的ESD保护方法

详述了目前用于亚微米ＣＭＯＳＩＣ的静电放电保护方法,比较了它们各自的特点,并详细阐述了栅耦合ＰＭＯＳ触发／ＮＭＯＳ触发横向可控硅ＥＳＤ保护电路的工作原理。     

Thermodynamic Modeling of Actinide Complexation with Acetate and Lactate at High Ionic Strength

The stability constants of NpO ₂ ⁺ , UO ₂ ²⁺ Am³⁺, and Th⁴⁺ with acetate and lactate anions has been measured in 0.3–5.0m NaCl media at 25°C by the solvent extraction technique. For the 1:1 complexation, the values of the stability constants increased in the order: NpO ₂ ⁺ < Am³⁺ < ₂ ²⁺ < Th⁴⁺, in accordance with the actinide charge density and reflecting the strongly ionic bonding of the complexes. The Pitzer ionic interaction parameters were calculated and used to estimate the thermodynamic stability constants at I = 0. Because our data were collected mainly in the high ionic strength region values of ⁽¹⁾ were estimated from values reported in the literature. For all stability constants the Pitzer model gives an excellent representation of the data using three interaction parameters ⁽⁰⁾, ⁽¹⁾, and COn leave from Institute of     

On a class of operators with finiterank self-commutators

This paper studies the class of pure operatorsA on a Hilbert space satisfying dimK _A <, where . The main tool is a pair of matrices and . A reproducing kernel Hilbert space model is introduced for a subclass of this class of operators. Some theorems are established for some subnormal operators as well as hyponormal operators in this class.     

Gd掺杂对Bi2Sr2Ca1-xGdxCu2Oy单晶载流子浓度和各向异性电阻率的影响

系统地研究了Gd掺杂对Bi2Sr2Ca1-xGdxCu2Oy单晶超导电性及各向异性电阻率的影响.Tc满足Tc/Tc,max=1-82.6(ax+b)2,并随Gd含量的增加而下降,这是由于Gd掺杂引起载流子浓度减小所导致.在x≥0.19时,ρab(T)在Tc附近有类半导体行为,dρab/dT随Gd含量增大而增大.ρc(T)呈半导体行为,并可用唯象公式ρc(T)=(a/T)exp(Δ/T)+bT+c加以描述.电阻率各向异性ρc/ρab随掺杂浓度增大而增大.     

A note on difference methods for the prediction of band-limitedsignals from past samples

Recent results are extended on difference methods for the prediction of bandlimited signals, obtained by D.H. Mugler and W. Splettstosser (1986, 1987) and by D.H. Mugler (1990), are extended to generalized bandlimited signals defined by M. Zakai (1965) and A.J. Lee (1975, 1976). This makes the difference method applicable to a wider class of signals