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
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The continuous progress in modern power device technology is increasingly supported by power-specific modeling methodologies and dedicated simulation tools. These enable the detailed analysis of operational principles on the the device and on the system level; in particular, they allow the designer to perform trade- off studies by investigating the operation of competing design variants in a very early stage of the development process. Furthermore, using predictive computer simulation makes it possible to analyze the device and system behavior not only under regularoperatingconditions, but also at the rim of the safe-operatingarea and beyond of it, where destructive processes occur that limit the lifetime of a power system.
標(biāo)簽: POWERHVMOS_Devices_Compact_Modeli ng
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Thepredecessorvolumeofthisbookwaspublishedin1996.Intheyears since then, some things have changed and some have not. Two of the things that have not changed are the desire for better models and faster simulations. I performed the original simulations on my “hyperfast” 133-MHz computer! At the time, I thought if I could just getafastercomputer,allofourSPICEproblemswouldbehistory,right? TodayIamsimulatingonacomputerthathasa2.6-GHzprocessorwith 512 MB of RAM, and I would still say that simulations run too slow. The computer technology has evolved, but so have the models. In 1996 wewereperformingsimulationson100-kHzpowerconverters,whereas today I routinely see 1- and 2-MHz power converters.
標(biāo)簽: Switch-Mode Simulation Supply Power
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Sensors are points ofcontact betweenthe material world ofatoms, mass, andenergy and the seemingly immaterial world of information, computation, and cognition. Linking these two domains more tightly yields all sorts of practical benefits, such as improvedinputdevicesforcomputers,moreeffectivemedicaldevices(implantedor worn), more precise agricultural operations, better monitored buildings or bridges, more secure payment systems, and more reliable sensor–actuator control systems. There are many settings in which tighter coupling between digital and physical planes can enhance safety, security, performance, and reliability.
標(biāo)簽: Computational RFID
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Identification is pervasive nowadays in daily life due to many complicated activities such as bank and library card reading, asset tracking, toll collecting, restricted access to sensitive data and procedures and target identification. This kind of task can be realized by passwords, bio- metric data such as fingerprints, barcode, optical character recognition, smart cards and radar. Radiofrequencyidentification(RFID)isatechniquetoidentifyobjectsbyusingradiosystems. It is a contactless, usually short distance, wireless data transmission and reception technique for identification of objects. An RFID system consists of two components: the tag (also called transponder) and the reader (also called interrogator).
標(biāo)簽: Processing Digital Signal RFID for
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Radio frequency identifi cation (RFID) technology is a wireless communication technology that enables users to uniquely identify tagged objects or people. RFID is rapidly becoming a cost-effective technology. This is in large part due to the efforts of Wal-Mart and the Department of Defense (DoD) to incorporate RFID technology into their supply chains. In 2003, with the aim of enabling pallet-level tracking of inventory, Wal-Mart issued an RFID mandate requiring its top suppliers to begin tagging pallets and cases, with Electronic Product Code (EPC) labels. The DoD quickly followed suit and issued the same mandate to its top 100 suppliers. This drive to incorporate RFID technology into their supply chains is motivated by the increased ship- ping, receiving and stocking effi ciency and the decreased costs of labor, storage, and product loss that pallet-level visibility of inventory can offer.
標(biāo)簽: A_Guide_to_Radio_Frequency_IDenti fication RFID
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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(biāo)簽: Essentials RFID
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Radio frequency identification (RFID) and Wireless sensor networks (WSN) are the two key wireless technologies that have diversified applications in the present and the upcoming systems in this area. RFID is a wireless automated recognition technology which is primarily used to recognize objects or to follow their posi- tion without providing any sign about the physical form of the substance. On the other hand, WSN not only offers information about the state of the substance and environment but also enables multi-hop wireless communications.
標(biāo)簽: Architecture Integrated RFID-WSN
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With more than two billion terminals in commercial operation world-wide, wire- less and mobile technologies have enabled a first wave of pervasive communication systems and applications. Still, this is only the beginning as wireless technologies such as RFID are currently contemplated with a deployment potential of tens of billions of tags and a virtually unlimited application potential. A recent ITU report depicts a scenario of “Internet of things” — a world in which billions of objects will report their location, identity, and history over wireless connections.
標(biāo)簽: Internet Things From The RFI of
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This book is about global navigation satellite systems (GNSS), their two main instru- ments, which are a receiver and a simulator, and their applications. The book is based on an operational off-the-shelf real-time software GNSS receiver and off-the-shelf GNSS signalsimulator.Theacademicversionsofthesetoolsarebundledwiththisbookandfree for readers to use for study and research.
標(biāo)簽: Navigation Geophysics Satellite Digital and
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