基于WAEEMD和MSB的滚动轴承故障特征提取

针对调制信号双谱（MSB）方法仅能处理平稳信号的不足,提出了一种基于加权平均集成经验模态分解（WAEEMD）和MSB的滚动轴承故障特征提取方法。首先,利用WAEEMD将滚动轴承的非平稳振动信号分解成一系列具有平稳特性的固有模态函数（IMF）;然后,开发了一种基于Teager能量峭度（TEK）的加权平均方法以强调敏感IMF的重要性,并将加权后的IMF重构为WAEEMD滤波信号;最后,应用MSB分解WAEEMD滤波信号中的调制分量并提取故障特征频率。仿真和实验结果表明,相对于快速谱峭度（FK）和EEMD-MSB方法,WAEEMD-MSB方法能更准确地获取故障特征,从而验证了WAEEMD-MSB方法的有效性。     

用TEK2714频谱分析仪测量网络的主要指标

本文介绍了测量C／N、C／CTB、C／CSO的三种方法。简要谈了CTB、CSO的频点选取。提出了使用TEK2714频谱分析仪．用工程常规测量法熟练测量C／N、C／CTB、C／CSO的方法。     

数字存储示波器现状初探

本文着重分析了数字存储示波器(DSO)的工作原理．功能与特点。最后．并以TEK(USA)、LeCroy(USA)两公司产品为例，介绍了当前高端数字存储示波器的现状。     

STORAGETEK2925磁带机子系统的工作原理

目前，ＳＴＯＲＡＧＥＴＥＫ２９２５磁带机广泛地用于野外地震采集系统中，由于在使用过程中故障率较高，文中通过介绍磁带机子系统的框图，分析ＭＴＳ及构成系统各板的工作原理，功能和作用及ＣＰ板在系统工作时的作用，来及时诊断和排除故障。     

基于本土主义的设计

Looking to Globally Important Agricultural Heritage Systems (GIAHS) sites and traditional ecological knowledge-based infrastructures (Lo–TEK), we find nature-based systems that symbiotically work with the environment. This article suggests that by hybridizing Lo–TEK with high-tech systems, the GIAHS sites could offer designers a toolkit towards economically, ecologically, culturally, and technologically innovative systems that can improve productivity and resilience. Whereas urban development results in the erasure of history, identity, culture and nature, this idea explores how urbanization can be an agent for the migration and reapplication of agricultural heritage systems, rather than their greatest threat. Cities can leap-frog the typical Western model of displacing indigenous diversity for homogenous high-tech. Instead, catalyzing localized, agricultural heritage landscapes like those designated as globally important agricultural heritage systems, as scalable, productive and resilient climate change solutions and technologies. It requires a shift in the thinking about traditional agriculture and about the relationship to Nature, from superior to symbiotic.