Power factor correction: Can it lower your electric bill? [My Favorite Experiment]

With economic times like these, everybody is looking for ways to save money. Now, imagine how appealing it would be if we consumers could cut our electric bills by up to 50% each month. No, I'm not talking about turning the thermostat down or turning your unused lights off (which you should be doing anyway); I'm talking about a onetime investment of a couple of hundred dollars for a home power factor corrector. Heck, even a 5% savings would pay for itself in about 3 years; not a bad deal! But before you start spending your savings, run an experiment, a valid and simple examination of the facts. And if you buy the equipment, make sure it can be returned, find out the refund policy, and then run an experiment before the refund period for returning the equipment expires. Just in case it doesn't work!     

青海电视台备播系统解决方案

通过对现有闲置设备情况和性能的分析,对这些设备重新设计改造,有效利用现有设备,盘活资产,节省了大量资金,同时达到电视播出系统的备份播出要求,保障电视节目的安全播出。     

通过LAN控制TDS3032B实现脉冲参数测量

针对如何通过TDS3032B示波器的LAN接口,实现脉冲频率、脉冲宽度、脉冲延时测量问题,本文描述了利用VISA函数通过LAN接口,在LabVIEW8．5开发环境下,根据测量功能的不同,发送不同的程控命令码,实现脉冲参数测量程序设计方法,该方法节约了购买Tektronix TDS3GV模块的经费,充分开发利用了仪器本身资源,达到了通过GPIB接口控制示波器的同样效果,读者可以直接利用程序中的原代码,避免程序设计中繁琐调试过程。应用证明此方法简单实用,对程序设计者具有参考借鉴价值。     

基于VC6.0及MOXA 2151I的故障信息短信通知系统设计

针对工业控制系统中需要远程监控功能但设备安装在恶劣环境下或不便于连接以太网的问题,系统采用GSM短信通信方式,硬件由MOXA 2151I短信模块和工控机构成,通过由VC6.0编写的监控软件给2151I发送AT指令从而实现将控制现场故障信息传输到远程监控站。结合在铝电解生产过程故障监测的应用证明,本方法可以减少值班人员数量和设备巡查频率,从而为企业节省至少一半的设备巡检成本。     

一种基于Qos区分对待请求任务的研究

鉴于在当前服务器面对请求任务过多,请求任务对服务质量也不一样。为了解决这问题,运用Qos的分类,标注,优先级设置的功能,对请求任务进行分类,标注,最后优先级设置,就可以将请求任务根据服务质量的不同进行区分进行实现。本文运用了分类中4种方法中基于源IP地址进行分类,在3次握手中对第一次握手的数据包进行识别分类,之后再它进行标注,这样其他网络设备才能方便地识别这种数据。最后进行优先级设置,这样处理请求任务时也有所根据。本文特别之处是可以让用户自己定义自己要求的服务质量,能真正做到"以人为本",这样服务器和客户都可以节省很多时间和资源,真正做到双赢。     

带电量显示的太阳能充电器设计

本文介绍了带电量显示的太阳能充电器,可实现太阳能充电和直流充电两种充电方式。该设计主要由太阳能电池板、锂电池、充电模块、升压模块、锂电池保护模块和电量显示模块等几个部分组成。把充电器放在一个有阳光的地方,即可以为手持设备提供一个方便的太阳能充电点,使户外充电变得便捷。     

基于LSI403LP DSP芯片的小型VoIP网关的设计

介绍了一个基于LSl403LP DSP芯片的小型VoIP网关的设计。它可提供4路RJ11接口供传统电话机接入，1路RJ-45接口连接Internet，还有一个RS-232接口供系统程序维护与升级。使用这种VoIP网关后，可使小型企业或家庭用户方便快捷地接入Internet，直接进行语音通信，不但便捷而且经济。给出了硬件和软件的结构设计。     

Structured cabling comes of age

Structured cabling has emerged as a basic building utility, comparable to heating and air conditioning, electricity or plumbing. it forms the essential communications infrastructure of a business's IT system, and is every bit as important as the equipment connected to each end of a piece of cable. Cabling is often overlooked or taken for granted, but a little time and effort in the choice of cabling system will save time, money and frustration in the near term, and, in the longer term, minimise the need for disruptive upgrades. A key objective for any structured cabling system is the capacity to handle with speed and reliability the huge data streams encountered in modern Internet and e-commerce applications. The system should also be capable of fast installation and deployment, which means that cabling components need to be modular, simple to use and, ideally, supplied in pre-qualified form. The author reviews the role of structured cabling in enabling the office IT infrastructure-today and into the future     

基于Verilog的I^2C控制器的设计与综合

为满足嵌入式系统中专用芯片功能不能达到系统要求的现状．设计出一种功能可扩展的I^2C sLave控制器,这种控制器与传统的专用I^2C芯片不同。专用的I^2C片的功能具有固定性,只能实现一种或两种功能,而这种控制器是在FPGA上实现的。由于FPGA本身就具有可编程性,因此这种控制器也可以实现不同的功能,采满足在嵌入式系...     

Setting up as a consultant the devil is in the details

Making a success of a consultancy means finding a niche where you can offer clients an edge over competing consultants. You cannot be all things to all people. If, for instance, you want to function as a customer's representative reviewing process designs, project economics and schedules, be sure to portray yourself as such. If you want to specialize in particular unit operations, you should emphasize that forte. Among other choices, you may intend to make your name as an expert witness, or as an economic and market analyst, an adviser on educational curricula, a counselor to government or nongovernmental organizations, or to equipment vendors or technology licensors; whatever the choice, be sure to advertise yourself specifically as such. In any case, be objective and never stretch the facts as to your capabilities. Later in this article, we give recommendations on how to market your services.     

河钢唐钢烧结主抽风机变频节能改造与实践

能源短缺和环境污染是人类当前共同面临的世纪性难题.我国自然资源总量排世界第七位,能源资源总量约4万亿吨标准煤,居世界第三位,但我国人口众多,能源资源相对匮乏.而作为我国在电力方面重点推广的节能技术之一的高压大功率变频调速技术,对于节能方面有着明显的效果.我国高压电动机总容量在1.5亿千瓦以上(不包括低压电动机),大部分为风机泵类负载,这些电动机大都由6kV/10kV驱动,它们大多工作在高能耗、低效率状态.如可根据所需的流量调节转速,就可获得很好的节电效果,一般可节电20％～50％.     

基于FPGA圆阵超声自适应波束形成的设计

设计了一种适于FPGA实现的圆阵数字自适应波束形成系统结构,系统采用FIR架构及延迟最小均方算法(DLMS),其中复数乘加模块采用循环移位乘加算法,自适应模块采用并行乘法器及时更新权系数。仿真结果表明基于FP-GA芯片实现数字自适应波束形成(DABF)具有实时性好,结构简单,易于实现等优点。     

基于语音识别技术的交际软件设计与实现

随着当今社会经济的发展与进步,国内外交流日益频繁,英语作为世界第一大语言,学好并掌握英语的重要性不言而喻。文章设计的基于语音识别技术的英语口语交际软件主要通过语音识别模块、情景对话数据库模块、语音合成模块、发音以及语境评测模块等共同作用,在突出情景口语教学的基础上再结合移动设备的便携性,提高学习者学习兴趣,不仅能够让使用者沉浸在英语对话氛围中提升语感,而且能够利用智能移动设备的便携性节省大量时间,进而提高使用者对英语的学习兴趣。     

基于LabVIEW的虚拟电路实验的设计

文中应用LabVIEW设计了电路课程中常见的实验模块,每个模块都给出了具体的程序设计方案,并最终成功进行了运行调试.基于虚拟仪器的引入,不但可以节约成本,而且更新和调整的实验方法和手段使得实验室的教学设备保持其先进性,提高了实验教学和科研的质量与效率,是实验教学的一个新的发展方向,促进了实验室技术的进步.     

鱼油萃取过程自动监控系统设计

萃取法具有操作可连续化,生产周期短,对热敏物质破坏少,保证鱼油良好品质的优点,但目前萃取法提取鱼油的控制系统相对落后。文章在分析鱼油萃取工艺过程的基础上,根据工艺要求设计自动监控系统,整个监控系统包含上位机和下位机两个部分,上位机实现对过程的远程监控、报警显示以及数据记录等功能,下位机以PLC为核心,实现现场控制、数据采集与转换以及回路调节等功能。系统自动化程度高、操作方便、可以为企业节省大量人力成本。     

低WSN服务能耗的MAC协议实现

为解决WSN服务能耗和服务质量问题,提出了一种无线传感器网络介质访问控制协议WTRP-S,分析比较了WTRP-S,WTRP和IEEE802.15.4MAC的性能,建立了节点启动调度模型。仿真结果表明:在数据业务大的网络中,该协议既能保证服务质量,在节点关闭通信模块中能够节省更多能量,使得整体能耗降低,WTRP-S适用于能量受限的无线传感器网络。     

测试用例自动生成方法的现状及研究

软件测试数据生成在软件系统开发费用中占很大比重。如果该过程能自动实现,则会极大地减少软件开发的周期和费用。测试用例的生成工作包含选定被测任务、分析输入数据、确定其取值并分析对应的输出数据。其中分析对应的输出数据是决定测试是否成功的关键环节。测试用例选取的一个中心原则,就是以用最少的测试用例找到尽可能多的错误。目前的工具尚不能完成自动生成测试用例这个环节,往往是只能采用人工选取的方法。按所采用的方法和研究对象的不同,将测试用例自动生成方法主要分为5类:基于有限状态集的测试,基于标注的转换系统的测试,针对面向模型的需求规格说明的测试,针对面向对象软件的测试,以及运用模型检查生成测试用例的方法。在简单介绍前4种方法之后,重点对模型检查的方法进行详细的分析和探讨。     

Dealing effectively with job loss-a unique approach to rebuilding your life

Are you one of the growing army of unemployed? Or are you afraid you might be soon? If so, you are one of millions in today's business world whose emotional structure has either collapsed or is in danger of collapsing. Your ability to cope, to function optimally, and to enjoy your life may, indeed, be in danger in the current business scene. In times like these, it is normal to feel a great sense of loss. As a result, you may even feel depressed. In order to pull yourself out of the doldrums and get on with your life, you'll need to find a way to regain some measure of stability so that you can replenish your confidence in yourself. This is a vital step that must be taken before you go out to find another job... the right job. If you don't pull yourself together, you will jeopardize the very result you want so badly: to get back into the workforce and reestablish your identity as a responsible, earning, worthwhile individual. The author briefly outlines a concept from her book 'Dealing effectively with job loss' on rebuilding the emotional and physical structure of your life.     

How much Reliability

Individually, we may be concerned about a smal portion of the reliability program, Such as probability of success, or economic considerations, or systems effectiveness, or one of the many other reliablility factors, when we should be looking at the whole picture. Reliability is not something that you buy by the piece or pound erdezem and just attach to the equipment, it is something that is inherent in the disian. This places a great responsibility on the design engineer. He must know the safety factor of each and every part, how they can fail, and how to compensate for all the variables. There is no part answer to ``how much reliability;' it involves many trade-offs, and the final decision will be made as a result of these trade-offs. When figuring ``how much reliability,' we must consider the routin engineering practices, then add how much it would cost using good reliability practices. Afte this is determined, one must assign a useful Iife span to the equipment, determine the cost of maintenance, the cost of owning the equipment, and the cost of idle equipment. From this informtion, good decisions can be made. There is no quick ans wer to ``how much reliability,' but it can easly be evalupted and the determination, made.     

无市电光缆站空调系统设计

在通信电源系统太阳能电池极板配置充分的条件下,利用其夏季富余的太阳能,为无市电光缆无人中继站的空调供中,既能达到降低站风温度、确保设备正常运行,提高通信系统可靠性的目的;同时又是对经济、实用绿色节能方法的探索。