高温箱内空气循环对热测试的影响与对策

通过热测试和热仿真试验来验证高温箱内空气循环对自冷设备高低温环境试验的影响。查阅相关的国内外标准并结合多年的热测试经验,提出一套标准试验程序和简易的测试方法,对自冷设备热测试或高低温环境试验有指导作用和应用价值。     

Effect of laser focus in two-color synthesized waveform on generation of soft x-ray high harmonics

Synthesis of multi-color laser pulses has been developed as a promising way to improve low conversion efficiency of high-order harmonic generation (HHG). Here we systematically study the effect of laser focus in a two-color waveform on generation of macroscopic HHG in soft x-rays. We find that the dependence of HHG yields on laser focus at low or high gas pressure is sensitive to the characteristics of single-atom harmonic response, in which "short"-or "long"-trajectory emissions can be selectively controlled by changing the waveform of two-color synthesized laser pulse. We uncover the phase-matching mechanism of HHG in the gas medium by examining the propagation of the two-color waveform and the evolution of time-frequency emissions of high-harmonic field. We further reveal that the nonlinear effects, such as geometric phase, atomic dispersion, and plasma defocusing, are responsible for modification of two-color waveform upon propagation. This work can be used to find better macroscopic conditions for generating soft x-ray HHG by employing two-color optimized waveforms.     

基于Flotherm阻尼模型3G通讯设备系统热仿真

文章介绍一种基于Flodlerm阻尼模黧系统热仿真的实用方法,并以某3G通讯设备系统热仿真为例,详细阐述该方法设计过程,通过系统热测试验证系统热仿真相关指标达到工程设计要求,从两证明系统热仿真的正确性。该方法对于复杂通讯设备系统热仿真其有很强指导作用和应用价值。     

高温箱内空气循环对自冷设备高低温环境试验影响与对策

文章通过热测试和热仿真试验验证高温箱内空气循环对自冷设备高低温环境试验的影响,针对此问题查阅相关国内外标准并结合笔者多年热测试经验。提出一套标准试验和简易测试方法,对自冷设备热测试或高低温环境试验有很强的指导作用和应用价值。     

通信设备的能效评估

节能减排正越来越多地被一些国家或地区作为市场准入的门槛,例如,在欧盟,EuP指令已经生效并被纳入CE认证体系;在美国,Verizon等主流运营商也推出了自己的能效标准,09年1月1日起实施;在中国,政府和众多采购商都在强势推出产品节能的要求。然而,实际能效评价标准却非常欠缺,特别是如何评价通信系统设备的能效还是众多厂商的一个难题。本文以美国Verizon最新发布的能效标准为基准,对通信设备的能效评估相应的分析和介绍,旨在让同行更多地了解国外新兴的市场准入要求和能效评估方法。