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Weber (unit) From Wikipedia, the free encyclopedia Jump to: navigation, search In physics, the weber (symbol: Wb;  /ˈveɪbər/, /ˈwɛbər/, or /ˈwiːbər/) is the SI unit of magnetic flux. A flux density of one Wb/m2 (one weber per square meter) is one tesla. The weber is named for the German physicist Wilhelm Eduard Weber (1804–1891). [edit] Definition

The weber may be defined in terms of Faraday's law, which relates a changing magnetic flux through a loop to the electric field around the loop. A change in flux of one weber per second will induce an electromotive force of one volt (produce an electric potential difference of one volt across two open-circuited terminals). Officially,

Weber (unit of magnetic flux) — The weber is the magnetic flux which, linking a circuit of one turn, would produce in it an electromotive force of 1 volt if it were reduced to zero at a uniform rate in 1 second.[1]

Public switched telephone network

is the network of the world's public circuit-switched telephone networks. It is a worldwide network of telephone lines, fiberoptic cables, microwave transmission links, cellular networks, communications satellites, and undersea telephone cables connected by switching centers, which allows any telephone in the world to communicate with any other. Originally a network of fixed-line analog telephone systems, the PSTN is now almost entirely digital in its core and includes mobile as well as fixed telephones.

(PSTN)

by Philip J. Corso

Contents Forward Introduction Chapter 01 - The Roswell Desert Chapter 02 - Convoy to Fort Riley Chapter 03 - The Roswell Artifacts Chapter 04 - Inside the Pentagon at the Foreign Technology Desk Chapter 05 - The Cover-up Chapter 06 - The Strategy Chapter 07 - The EBE Chapter 08 - The Project Gets Under Way Chapter 09 - The Project Had Officially Begun Chapter 10 - The U2 Program and Project Corona - Spies in Space Chapter 11 - Project Moon Base Chapter 12 - The Integrated Circuit Chip - From the Roswell Crash Site to Silicon Valley Chapter 13 - The Laser Chapter 14 - The Antimissile Missile Project Chapter 15 - My Last Year in R&D - The Hoover Files, Fiber Optics, Supertenacity, and Other Artifacts Chapter 16 - 'Tesla’s Death Ray' and the Accelerated Particle Beam Weapon Chapter 17 - Star Wars Afterword

Near field communication (NFC) is a set of standards for smartphones and similar devices to establish radio communication with each other by touching them together or bringing them into close proximity, usually no more than a few centimetres. Present and anticipated applications include contactless transactions, data exchange, and simplified setup of more complex communications such as Wi-Fi.[1] Communication is also possible between an NFC device and an unpowered NFC chip, called a "tag".[2]

NFC standards cover communications protocols and data exchange formats, and are based on existing radio-frequency identification (RFID) standards including ISO/IEC 14443 and FeliCa.[3] The standards include ISO/IEC 18092[4] and those defined by the NFC Forum, which was founded in 2004 by Nokia, Philips and Sony, and now has more than 160 members. The Forum also promotes NFC and certifies device compliance.[5

What is Arduino?

Arduino is a tool for making computers that can sense and control more of the physical world than your desktop computer. It's an open-source physical computing platform based on a simple microcontroller board, and a development environment for writing software for the board.

Inexpensive - Arduino boards are relatively inexpensive compared to other microcontroller platforms. The least expensive version of the Arduino module can be assembled by hand, and even the pre-assembled Arduino modules cost less than $50