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
上传时间: 2020-06-07
上传用户:shancjb
One of the predominant topics in the domain of the emerging Smart Grid can be seen in standardization. With the combination of existing protection and automa- tion technology with upcoming ICT-based solutions, different interoperability is- sues arise when technologies have to be combined in the infrastructure. Standards have proven to be one of the most striking solutions to actually cope with this topic. Since 2008, this topic has gained much attention in various political and technical agendas.
标签: Standardization Smart Grids in
上传时间: 2020-06-07
上传用户: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.
标签: Essentials RFID
上传时间: 2020-06-08
上传用户:shancjb
RFID networks are currently recognized as one a research area of priority. Research activities related to RFID technology have been booming recently. A number of ongoing projects are being funded in Europe, Asia, and North America. According to leading market analysts, the development of the RFID market is projected to increase from approximately $3 billion in 2005 to $25 billion in 2015. Several countries have dedicated innovation programs to support and develop RFID systems and related technologies: the RFID initiative in Taiwan, Ubiquitous Japan and the NSF SBIR program in the USA. The EU has recently advertised its Strategic Research Roadmap concerning the Internet of Things, which first of all refers to the RFID technology before being extended to commu- nicating devices as in M2M (Machine to Machine). In this roadmap, several application domains have been identified:
上传时间: 2020-06-08
上传用户:shancjb
To a quantum mechanic the whole universe is one godawful big interacting wavefunction ? but to the rest of us, it’s a world full of separate and distinguishable objects that hurt us when we kick them. At a few months of age, human children recognize objects, expect them to be permanent and move continuously, and display surprise when they aren’t or don’t. We associate visual, tactile, and in some cases audible and olfactory sensations with identifiable physical things. We’re hardwired to understand our environment as being composed of separable things with specific properties and locations. We understand the world in terms of what was where when.
上传时间: 2020-06-08
上传用户:shancjb
I can remember buying my first electronic calculator. I was teaching a graduate level statistics course and I had to have a calculator with a square root function. Back in the late 1960s, that was a pretty high-end requirement for a calculator. I managed to purchase one at the “educational discount price” of $149.95! Now, I look down at my desk at an ATmega2560 that is half the size for less than a quarter of the cost and think of all the possibilities built into that piece of hardware. I am amazed by what has happened to everything from toasters to car engines. Who-da-thunk-it 40 years ago?
上传时间: 2020-06-09
上传用户:shancjb
Artificial Intelligence (AI) has undoubtedly been one of the most important buz- zwords over the past years. The goal in AI is to design algorithms that transform com- puters into “intelligent” agents. By intelligence here we do not necessarily mean an extraordinary level of smartness shown by superhuman; it rather often involves very basic problems that humans solve very frequently in their day-to-day life. This can be as simple as recognizing faces in an image, driving a car, playing a board game, or reading (and understanding) an article in a newspaper. The intelligent behaviour ex- hibited by humans when “reading” is one of the main goals for a subfield of AI called Natural Language Processing (NLP). Natural language 1 is one of the most complex tools used by humans for a wide range of reasons, for instance to communicate with others, to express thoughts, feelings and ideas, to ask questions, or to give instruc- tions. Therefore, it is crucial for computers to possess the ability to use the same tool in order to effectively interact with humans.
标签: Embeddings Processing Language Natural in
上传时间: 2020-06-10
上传用户:shancjb
Wherever possible the overall technique used for this series will be "definition by example" withgeneric formulae included for use in other applications. To make stability analysis easy we will usemore than one tool from our toolbox with data sheet information, tricks, rules-of-thumb, SPICESimulation, and real-world testing all accelerating our design of stable operational amplifier (op amp)circuits. These tools are specifically targeted at voltage feedback op amps with unity-gain bandwidths<20 MHz, although many of the techniques are applicable to any voltage feedback op amp. 20 MHz ischosen because as we increase to higher bandwidth circuits there are other major factors in closing theloop: such as parasitic capacitances on PCBs, parasitic inductances in capacitors, parasitic inductancesand capacitances in resistors, etc. Most of the rules-of-thumb and techniques were developed not justfrom theory but from the actual building of real-world circuits with op amps <20 MHz.
标签: 运算放大器
上传时间: 2021-11-01
上传用户:
It all started rather innocuously. I walked into Dr GT Murthy’s office one fine day, andchanged my life. “Doc” was then the General Manager, Central R&D, of a very largeelectrical company headquartered in Bombay. In his new state-of-the-art electronics center,he had hand-picked some of India’s best engineers (over a hundred already) ever assembledunder one roof. Luckily, he too was originally a Physicist, and that certainly helped me gainsome empathy. Nowadays he is in retirement, but I will always remember him as athoroughly fair, honest and facts-oriented person, who led by example. There were severalthings I absorbed from him that are very much part of my basic engineering persona today.You can certainly look upon this book as an extension of what Doc started many years agoin India … because that’s what it really is! I certainly wouldn’t be here today if I hadn’t metDoc. And in fact, several of the brash, high-flying managers I’ve met in recent years,desperately need some sort of crash course in technology and human values from Doc!
标签: 开关电源
上传时间: 2021-11-23
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The PW3130 series product is a high integration solution for lithium-lion/polymer batteryprotection.PW3130 contains advanced power MOSFET, high-accuracy voltage detection circuits anddelay circuits. PW3130 is put into an ultra-small SOT23-5 package and only one external componentmakes it an ideal solution in limited space of battery pack. PW3130 has all the protection functionsrequired in the battery application including overcharging, overdischarging, overcurrent and loadshort circuiting protection etc. The accurate overcharging detection voltage ensures safe and fullutilization charging.The low standby current drains little current from the cell while in storage. Thedevice is not only targeted for digital cellular phones, but also for any other Li-Ion and Li-Polybattery-powered information appliances requiring long-term battery life
标签: pw3130
上传时间: 2022-02-11
上传用户:fliang