浅析机电一体化技术的现状和发展趋势

机电一体化是现代科学技术发展的必然结果,该文简述了机电一体化技术的基本概要和发展背景,综述了国内外机电一体化技术的现状,分析了机电一体化技术的发展趋势。     

GOEBEL分切机卸辊车改造

主要介绍了恒丰纸业股份有限公司从德国引进的GOEBEL OPTIMA-1650盘纸分切机卸辊装置的改进,实现了机械自动卸辊,大大降低了劳动强度,提高了工作效率。     

机场中心变电所二次系统设计要点

结合某机场35kV中心变电所的二次接线系统设计，对继电保护、自动装置、闭锁、特殊操作系统等项目的设计要点进行了介绍。说明建立完备的变电所二次接线系统是保障变电所可靠运行的重要环节。     

黄金冶炼生产工艺现状及发展

黄金冶炼行业发展十分迅速,不断有新的生产技术和工艺涌现。文中主要阐述了黄金冶炼生产工艺中的选矿、预处理、浸出、提取与回收、精炼等过程单元的技术现状与发展,同时分析了各个过程单元中主流工艺的特点。     

Grapevine canopy response to a high‐temperature event during deficit irrigation

Background and Aims: Despite much anecdotal evidence, there has been little scientific investigation of the potential effects of a high‐temperature event on grapevines during deficit irrigation. This study examined the interaction between temperature and water status on leaf physiology. Methods and Results: Two experiments used Cabernet Sauvignon cuttings grown in a glasshouse at approximately 27–30°C before deficit irrigation treatments were imposed. When water stress was apparent, a 2‐day high‐temperature event with maximum daytime temperatures of approximately 40–45°C was generated. Leaf damage, stomatal conductance and water potential of deficit‐irrigated vines were all affected to a greater extent than in the well‐watered vines. Conclusions: The negative effects of a high‐temperature event on vine physiology were more severe in vines experiencing water stress than in well‐watered vines, but recovery was rapid even without re‐watering. Significance of the Study: An increase in the use of deficit irrigation will lead to a greater likelihood of vines being water stressed on hot days, and the observed responses indicate that this will result in greater damage to the vine.     

煤矿瓦斯巡检管理系统的原理及设计

为及时发现矿井瓦斯的安全隐患,降低事故的发生率,采用热催化原理,通过数据传输接口设计连接到计算机,把巡检的数据信息发送到计算机处理的煤矿瓦斯巡检管理系统,可以有效地协助煤矿做好瓦斯检查管理工作。重点介绍该系统的原理,主要组成和功能。     

人防地下室通风设计若干问题的分析

针对平战结合五、六级附建式人防地下室通风设计过程中出现的一些常见问题,结合实例进行分析,提出解决问题的办法和建议。     

Direct parameter-extraction method for MOSFET noise model from microwave noise figure measurement

A new method for the determination of the four noise parameters of the metal oxide semiconductor field effect transistors (MOSFETs) based on the noise figure measurement system without microwave tuner is presented. The noise parameters are determined based on a set of analytical expressions of noise parameters by fitting the measured noise figure of the active device. These expressions are derived from an accurate small signal and noise equivalent circuit model, which takes into account the substrate parasitics, pad capacitances, and series inductances. On-wafer experimental verification is presented and a comparison with tuner based method is given. Good agreement is obtained between simulated and measured results for 0.5 × 5 × 16 μm, 0.35 × 5 × 16 μm and 0.18 × 5 × 16 μm (gate length × number of gate fingers × unit gate width) MOSFETs.     

嵌入式Linux中的Nand Flash驱动详解

在嵌入式设备中,Nand Flash的应用十分广泛并且不可缺少,该文从设备的注册到驱动加载对Nand Flash控制器的驱动进行深入分析,同时阐述了Linux内核中的相关机制,为NandFlash等设备驱动的移植及编写提供指导.     

劣弧半径的测量工装

提出了对劣弧半径测量的必要性,并介绍了一种新的采用工装测量来计算劣弧半径的方法,而且对此工装的测量和公式的依据进行了详细的解释及推导,这种测量方式可在工厂的实际应用中得到推广。