December 2007, San Jose, California: It seems a long time ago. I walked into a big networking company to head their small Power over Ethernet (PoE) applications team. Surprisingly, I hardly knew anything about PoE prior to that day, having been a switching-power conversion engineer almost all my life. But it seemed a Great opportunity to widen my horizons. As you can see, one notable outcome of that seemingly illogical career choice five years ago is the book you hold in your hands today. I hope this small body of work goes on to prove worthy of your expectations and also of all the effort that went into it. Because, behind the scenes, there is a rather interesting story to relate—about its backdrop, intertwined with a small slice of modern PoE history, punctuated by a rather res- tive search for our roots and our true heroes, one that takes us back almost two centuries
上傳時間： 2020-06-07
上傳用戶：shancjb
In order to enhance the efficiency and reliability of the power grid, diversify energy resources, improve power security, and reduce greenhouse gas emission, many countries have been putting Great efforts in designing and constructing their smart grid(SG) infrastructures.Smart gridcommunicationsnetwork(SGCN) is oneof the key enabling technologies of the SG. However, a successful implementation of an efficient and cost-effective SGCN is a challenging task
上傳時間： 2020-06-07
上傳用戶：shancjb
LIKE SO MANY OTHERS , THIS BOOK WAS WRITTEN BECAUSE WE COULDN ’ T FIND ONE LIKE IT . We needed something to hand to all of those people who have come to us asking for “a good book to read on RFID.” When we looked for candidates we found some Great books, but most were aimed at electrical engineers or top-level managers, with very little for those of us who are in between. This book is for developers, system and software architects, and project managers, as well as students and professionals in all of the industries impacted by Radio Frequency Identification (RFID) who want to understand how this technology works. As the title suggests, this book is about RFID in general and not just the most recent developments; however, because so much is going on in the area of RFID for the supply chain and especially the Electronic Product Code (EPC), we have devoted consider- able space to these topics. Regardless of the type of RFID work you may be doing, we think you will find something useful here.
標簽： Essentials RFID
上傳時間： 2020-06-08
上傳用戶：shancjb
研究一種智能掃地機器人。從硬件系統控制模塊設計到主要技術調試進行了較詳細的闡述。以STM32單片機為控制核心與電機驅動、紅外線路徑識別模塊等相互協調應用。進行電路搭建和程序編寫。實現了智能掃地機器人紅外線避障和自動掃地功能,其清掃面積能達到約70%,清掃率約60%,很大程度受到自身機械機構的限制,后期將對小車的機械結構進行完善。This paper studies an intelligent sweeping robot.From the hardware system control module design to the main technical debugging are described in detail.STM32 MCU is used as the control core to coordinate with motor drive and infrared path recognition module.Conduct circuit building and programming.The functions of infrared obstacle avoidance and automatic sweeping of intelligent sweeping robot are realized.Its cleaning area can reach about 70%and the cleaning rate is about 60%.Because it is limited by its own mechanical mechanism to a Great extent,the mechanical structure of the car will be improved in the later stage.
標簽： 掃地機器人
上傳時間： 2022-03-26
上傳用戶：
摘要：本文在分析1GBT的動態開關特性和過流狀態下的電氣特性的基礎上，通過對常規的IGBT推挽驅動電路進行改進，得到了具有良好過流保護特性的IGBT驅動電路。該電路簡單，可靠，易用，配合DSP等控制芯片能達到很好的驅動效果Abstract：Based on the studies on the dynamic switching and over-current characteristics of IGBT，this paper makes some improvments to the original push-pull driving circuit，obtains a new IGBT driving circuit which has a good over-current protection function.The circuit is simple，reliable and easy to use.Combined with controlling chips such as DSP it will do a Great job in driving applications.關鍵詞：IBGT：開關特性；驅動；過流保護；Key Words:IGBT；switching characteristics；driving:over-current protection
上傳時間： 2022-06-21
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