DSP+FPGA数据处理系统的研究与应用

针对铣削加工中心主轴刚度检测系统实时性的要求,重点阐述了DSP FPGA的数字硬件系统和流水线结构的CORDIC算法在FPGA中的实现,并通过仿真和实验对CORDIC算法的理论值和计算数值进行对比分析,结果表明,计算数值非常接近理论值.     

美国流体动力工程研究中心简介

本文简要介绍了美国国家流体动力工程中心的基本情况、研究方向和教学计划.在此基础上对我国流体动力传动与控制的科研单位和企业的发展提出了一些看法.     

增量式旋转轴定向的应用实例

绝对值编码器能够准确地保持坐标位置,因此在需要定位或定向时常选用这种编码器.但某些时候由于改造的机械或者资金情况的限制只能使用增量式编码器,文中旨在讨论在这种情况下如何实现旋转轴的定向和定位.     

"认知"是信息化应用的绊脚石——访中国航天时代电子公司第十六研究所、七一七一厂信息处处长徐四海

此次航空航天信息化的大型选题报道让记者有幸来到地处关中平原,沃野千里,依山傍水,是与罗马并称为世界古都的"西安"进行一线采访.经过一夜的风雨洗礼,让西安这座古城尤显清新爽朗,仿佛这场风雨是特意为迎接我们而将这座城市冲刷地如此洁净,街道两旁郁郁葱葱的热带植物让你犹如置身南方小城一般.而我们此行的第一站便是位于西安市南郊航天城的中国航天时代电子公司第十六研究所、七一七一厂(以下简称7171厂).     

清理沼气废液废渣仅用五分钟

7月25日上午,江苏省农机具开发应用中心陈新华副主任、农业部南京农机化研究所陈永生主任等5人,来到江苏涟水县与农机局有关人员一起进行沼气清渣车清渣试验.研制成功的清渣车在小李集办事处胡楼村吴国成家中现场进行沼气池清渣,一池沼气废液废渣清理完毕,仅用5分钟,省时,省工,安全,效果很好.     

AJAX核心技术解析

AJAX是Asynchronous JavaScript and XML的缩写,是一种新的Web开发技术.AJAX使客户端能在后台访问服务器并可按需求取回数据,从而避免了整个页面的刷新.这为交互较多、频繁读数据的Web应用提供了一个很好的解决方案.     

船舶ERP选型:集成性是关键

当前,信息化已经渗透到世界船舶工业的设计、生产、管理、服务等方方面面,其应用的深度与广度决定了行业综合水平的高低,成为大至一个国家的船舶工业、小至一个船舶企业能否在市场中生存和发展的关键.当造船业已经普遍意识到,以"信息化推动造船现代化"是中国造船工业追赶国际先进水平的最后机遇时,造船业的生存发展与IT厂商的策略几乎在同一时间不谋而合,在造船业竞争的搏奕中厂商的相助少不了.     

2007年中国机床工具行业十大新闻

1.中央和地方省市主要领导频繁视察机床行业企业,国家为数控机床产业发展创造了空前良好的发展环境 胡锦涛、吴邦国、温家宝、贾庆林、李长春等党和国家领导人以及辽宁、黑龙江、山东、江苏、云南、湖北、广东、陕西、浙江、天津、重庆等省市主要领导相继视察了机床工具厂和数控系统厂.各级领导频繁视察,为数控机床产业的发展创造了空前良好的发展环境.     

走区域应用示范与技术创新服务体系新模式

东营市位于黄河入海口,是黄河三角洲的中心城市,是在石油矿区基础上建设起来的新兴工业城市.近年来,除石油工业外,石油化工、盐化工、造纸、机电、轻纺、建材及生物医药等制造业门类得到较快发展,涌现出一批实力较强的企业集团,制造业逐步在东营市经济发展中占据了重要地位.     

时尚消费中畅销产品的设计

畅销产品具有引导潮流的创意、造型和功能的统一,能够满足情感价值、是艺术品般的产品等特征,所有这些特征都是以消费者为中心的,归根到底是满足了消费者希望拥有的产品诉求.     

便携式可见分光光度计测定桂圆中二氧化硫

采用便携式可见分光光度计测定桂圆中二氧化硫含量。结果表明,二氧化硫在0~120mg/kg范围内线性关系为y=0.99Abx-0.007,相关系数为0.999;重复性为9.0%。与实验室检测数据相比偏差为2.2%~9.0%。实验证明便携式可见分光光度计测定桂圆中二氧化硫的结果与实验室测定结果相当,可以用于桂圆中二氧化硫含量。     

Sulphur emissions from engine oil: Information from the sulphur emission index

Data published by the Institute of Materials including information on the volatility, sulphur content, and sulphur volatility of 913 engine oils were compiled. These engine oils were collected in three geographic regions: North America, Europe, and Asia. The volatility data were generated using a Selby—Noack instrument in which all volatilised material is collected for the further analysis of phosphorus and sulphur content. It was found that under the normal Noack test exposure conditions of 250°C for one hour, the sulphur emission index (a measure of sulphur volatility in mg/l) varied markedly among the engine oils. In a correlation study, a minor correlation of up to %R²= 15 was found between sulphur volatility and oil volatility while a greater correlation of up to %R² = 39 was found between sulphur volatility and sulphur content of the formulated engine oils. A new concept and application of the sulphur volatility ratio may be useful in explaining the observations concerning sulphur volatility dependence.     

A Device for Ozone Production and Deactivation of Smoke Gases Based on an Electric Discharge Developing in the Runaway-Electrons Mode

A device for ozone production and deactivation of smoke gases has been designed. It is based on a high-voltage nanosecond electric discharge developing in the mode of runaway electrons at atmospheric pressure. The first experiments have shown high efficiency in the device operation. The specific energy consumption in the ozone production was 3.3 × 10⁷ J/kg. Purification from smoke requires an energy consumption of 1.3 × 10^–18 J per molecule of sulphur dioxide at a 50% degree of purification. Improvement of the device is planned.     

基于高压水射流清洗技术的研究

高压水射流技术发展迅速,并广泛的应用于工业清洗、除锈、切割等方面.高压水射流清洗技术因其无污染、成本低、应用广而备受人们重视.为了更加有效应用高压水射流进行表面清洗,本文分析了高压水射流清洗技术的优点、清洗原理、清洗参数的确定、高压水系统装置的组成,为更好地应用高压水射流提供了设计依据.     

高压变频技术在电弧炉除尘系统中的应用

在分析了电弧炉设备的运行现状和研究了电弧炉除尘系统特点的基础上，通过Harsvert—A型高压变频器在某炼钢厂除尘系统改造中的应用实例，介绍了高压变频技术在炼钢厂电弧炉除尘系统中的成功应用。实例证明，该变频技术在节能降耗、提高自动化控制水平方面具有很好的应用前景。     

核心网联合跟踪技术原理与实现

联合跟踪技术实现了对故障的快速定位和深入分析,是一种有效的定点排除故障的手段.概述了设备支持的2种跟踪方式,分析了MSC收到消息参数之后的跟踪流程、HLR的功能及其在联合跟踪技术中的作用,并举例进行分析.     

Corrosive effect of acrylic acid on magnetic head and media of an operating hard disk drive

Magnetic heads and media in a magnetic hard disk drive are often attacked by corrosive gases, such as hydrochloric acid, sulphur dioxide and acrylic acid, ect. In this paper, we investigate the corrosion progress of heads and media subject to contact-start-stop (CSS) operation under diluted acrylic acid vapor attack. It is found that under elevated temperature and humidity, acrylic acid vapor not only accelerates the magnetic hard disk media corrosion rate at carbon overcoat pinhole locations, but also induces new corrosion products such as cobalt acrylate and nickel acrylate. Different corrosion pattern at tribological contact area and non-contact area in an operating hard disk drive are observed and the related corrosion mechanism is discussed. This paper presents a view of corrosion products and corrosion progress at the different locations of magnetic heads and media under the diluted acrylic acid vapor attack in an operating hard disk drive.     

核心网联合跟踪技术原理与实现

联合跟踪技术实现了对故障的快速定位和深入分析,是一种有效的定点排除故障的手段。概述了设备支持的2种跟踪方式,分析了MSC收到消息参数之后的跟踪流程、HLR的功能及其在联合跟踪技术中的作用,并举例进行分析。     

A practical device for processing Polaroid 55 P-N film used with scanning electron microscopes

Nematodes and mildew-infected barley leaves when examined in the scanning electron microscope after critical point drying (CPD) from sulphur dioxide (critical temperature 157–7°C) showed no obvious physical damage, but the specimens had a surface deposit which was probably heat damaged natural waxes. The nematode Caenorhabditis elegans and clover roots (Trifolium subterraneum) showed no physical or heat damage after CPD from monochlorodifluoromethane (Freon 22, critical temperature 96°C). The hyphæ and conidia of unfixed mildew on barley were damaged after CPD from Freon 22, probably due to the Freon extracting lipids from the cell walls. Freon 22 was preferred for most specimens as it is cheap, easy to get and not very toxic.     

自动电位滴定法测定馏分燃料中的硫醇硫及银-硫化银电极的制备

测定燃料中的硫醇硫含量是评价馏分燃料质量的一个重要指标.国家标准GB 1792-88规定采用手动电位滴定法测定馏分燃料中的硫醇硫,滴定过程较难控制.本文采用电位滴定法,操作简易,测量结果准确.对滴定所用指示电极银一硫化银电极的制备方法作了改进.