Monday, December 21, 2015

The rebirth of an ancient technology



Besides its obvious use, a flashlight can be toggled on and off to send Morse coded signals for requesting help and rescue.

They developed a device which could send messages using electrical signals to line up compass needles on a grid containing letters of the alphabet. Then, in 1838, Samuel Morse and his assistant, Alfred Vail, demonstrated an even more successful telegraph device which sent messages using a special code - Morse code.

..The rampage of LI FI (irrelavant adrenaline).



I look as I watching the LED light Li-Fi (Light Fidelity) is a bidirectional, high speed and fully networked wireless communication technology similar to Wi-Fi. Coined by Prof. Harald Haas,[1] Li-Fi is a subset of optical wireless communications (OWC) and can be a complement to RF communication (Wi-Fi or Cellular network), or a replacement in contexts of data broadcasting. It is so far measured to be about 100 times faster than Wi-Fi, reaching speeds of 224 gigabits per second.[2]
It is wireless and uses visible light communication or infra-red and near ultraviolet (instead of radio frequency waves) spectrum, part of optical wireless communications technology, which carries much more information, and has been proposed as a solution to the RF-bandwidth limitations.[3] A complete solution includes an industry led standardization process.
Technology details[edit]
This OWC technology uses light from light-emitting diodes (LEDs) as a medium to deliver networked, mobile, high-speed communication in a similar manner to Wi-Fi.[4] The Li-Fi market is projected to have a compound annual growth rate of 82% from 2013 to 2018 and to be worth over $6 billion per year by 2018.
Visible light communications (VLC) works by switching the current to the LEDs off and on at a very high rate, too quick to be noticed by the human eye. Although Li-Fi LEDs would have to be kept on to transmit data, they could be dimmed to below human visibility while still emitting enough light to carry data.The light waves cannot penetrate walls which makes a much shorter range, though more secure from hacking, relative to Wi-Fi.] Direct line of sight isn't necessary for Li-Fi to transmit a signal; light reflected off the walls can achieve 70 Mbit/s.
Li-Fi has the advantage of being useful in electromagnetic sensitive areas such as in aircraft cabins, hospitals and nuclear power plants[citation needed] without causing electromagnetic interference.[8][9] Both Wi-Fi and Li-Fi transmit data over theelectromagnetic spectrum, but whereas Wi-Fi utilizes radio waves, Li-Fi uses visible light. While the US Federal Communications Commission has warned of a potential spectrum crisis because Wi-Fi is close to full capacity, Li-Fi has almost no limitations on capacity. The visible light spectrum is 10,000 times larger than the entire radio frequencyspectrum.Researchers have reached data rates of over 10 Gbit/s, which is much faster than typical fast broadband in 2013.Li-Fi is expected to be ten times cheaper than Wi-Fi. Short range, low reliability and high installation costs are the potential downsides.
PureLiFi demonstrated the first commercially available Li-Fi system, the Li-1st, at the 2014 Mobile World Congress in Barcelona.
Bg-Fi is a Li-Fi system consisting of an application for a mobile device, and a simple consumer product, like an IoT (Internet of Things) device, with color sensor, microcontroller, and embedded software. Light from the mobile device display communicates to the color sensor on the consumer product, which converts the light into digital information. Light emitting diodes enable the consumer product to communicate synchronously with the mobile device.
History
Professor Harald Haas, from the University of Edinburgh in the UK, is widely recognised as the original founder of Li-Fi. He coined the term Li-Fi and is Chair of Mobile Communications at the University of Edinburgh and co-founder of pure LiFi.
The general term visible light communication (VLC), includes any use of the visible light portion of the electromagnetic spectrum to transmit information. The D-Light project at Edinburgh's Institute for Digital Communications was funded from January 2010 to January 2012. Haas promoted this technology in his 2011 TED Global talk and helped start a company to market it. PureLiFi, formerly pureVLC, is an original equipment manufacturer (OEM) firm set up to commercialize Li-Fi products for integration with existing LED-lighting systems.
In October 2011, companies and industry groups formed the Li-Fi Consortium, to promote high-speed optical wireless systems and to overcome the limited amount of radio-based wireless spectrum available by exploiting a completely different part of the electromagnetic spectrum.
A number of companies offer uni-directional VLC products       



around flashing the flaming torch on everything the cold feeling deep inside the pits of my under arm. Closing the door I shut out the rain and pull Samantha over, close to me, close to my knife. The main room is rather stupid, the throne is somewhat have these little descriptions explaining the items above, written in older Hebrew, the suit of armor is metallic alloy with the flipper on the helmet. Strangely, I don’t feel nothing in my gut.Nothing but anger, no sadness, just an empty numbness. The bitch stumbling weekly as I pull her along, like we’ve been walking for ages, unlocking the hall’s door, I pull it open there the garden, a bunch of bushes and flowers. The rain is crashing down while I lead the way to the forest beyond. Back inside I close the door, Samantha continue to look around she think this is the place where she is going to die, the numbness still inside me, it worse than anything I felt before, I would be using a muffler or as an heartless rapist weather it suit me at the moment, I’m on rampage now, on my feet, I storm throughout the dungeon, screaming, ranting, Samantha backed into the corner, screaming in horror, terrifies as I throw the iron maiden over, kick the pillory down, kicking them while screeching up a storm more violent than outside. “Fuck you.” In a sharp shift, I go barreling down on her, she recoils, unable to raise her hands defensively, backed into the corner next to the utility door crying out in panic.. I’m on rampage how.This hormone is produced by the adrenal glands which lie at the tops of the kidneys. Normally a small amount of adrenaline is produced and this helps to ... Adrenaline….. I’m on rampage now…

         , which is not the same as Li-Fi.[citation needed]
VLC technology was exhibited in 2012 using Li-Fi.[24] By August 2013, data rates of over 1.6 Gbit/s were demonstrated over a single color LED.[25] In September 2013, a press release said that Li-Fi, or VLC systems in general, do not require line-of-sight conditions.[26] In October 2013, it was reported Chinese manufacturers were working on Li-Fi development kits.[27]
In April 2014, the Russian company Stins Coman announced the development of a Li-Fi wireless local network called BeamCaster. Their current module transfers data at 1.25 gigabytes per second but they foresee boosting speeds up to 5 GB/second in the near future.[28] In 2014 a new record was established by Sisoft (a Mexican company) that was able to transfer data at speeds of up to 10Gbps across a light spectrum emitted by LED lamps[
Standards[edit]
Like Wi-Fi, Li-Fi is wireless and uses similar 802.11 protocols; but it uses visible light communication (instead of radio frequency waves), which has much wider bandwidth.
One part of VLC is modeled after communication protocols established by the IEEE 802 workgroup. However, the IEEE 802.15.7 standard is out-of-date, it fails to consider the latest technological developments in the field of optical wireless communications, specifically with the introduction of optical orthogonal frequency-division multiplexing (O-OFDM) modulation methods which have been optimized for data rates, multiple-access and energy efficiency.[30] The introduction of O-OFDM means that a new drive for standardization of optical wireless communications is required.
Nonetheless, the IEEE 802.15.7 standard defines the physical layer (PHY) and media access control (MAC) layer. The standard is able to deliver enough data rates to transmit audio, video and multimedia services. It takes into account optical transmission mobility, its compatibility with artificial lighting present in infrastructures, and the interference which may be generated by ambient lighting. The MAC layer permits using the link with the other layers as with the TCP/IPprotocol.[citation needed]
The standard defines three PHY layers with different rates:
·         The PHY I was established for outdoor application and works from 11.67 kbit/s to 267.6 kbit/s.
·         The PHY II layer permits reaching data rates from 1.25 Mbit/s to 96 Mbit/s.
·         The PHY III is used for many emissions sources with a particular modulation method called color shift keying (CSK). PHY III can deliver rates from 12 Mbit/s to 96 Mbit/s.


The modulation formats recognized for PHY I and PHY II are on-off keying (OOK) and variable pulse position modulation(VPPM). The Manchester coding used for the PHY I and PHY II layers includes the clock inside the transmitted data by representing a logic 0 with an OOK symbol "01" and a logic 1 with an OOK symbol "10", all with a DC component. The DC component avoids light extinction in case of an extended run of logic 0's.[citation needed]
The first VLC smartphone prototype was presented at the Consumer Electronics Show in Las Vegas from January 7–10 in 2014. The phone uses SunPartner's Wysips CONNECT, a technique that converts light waves into usable energy, making the phone capable of receiving and decoding signals without drawing on its battery. A clear thin layer of crystal glass can be added to small screens like watches and smartphones that make them solar powered. Smartphones could gain 15% more battery life during a typical day. This first smartphones using this technology should arrive in 2015. This screen can also receive VLC signals as well as the smartphone camera. The cost of these screens per smartphone is between $2 and $3, much cheaper than most new technology.
Philips lighting company has developed a VLC system for shoppers at stores. They have to download an app on their smartphone and then their smartphone works with the LEDs in the store. The LEDs can pinpoint where they are located in the store and give them corresponding coupons and information based on which aisle they are on and what they are looking at.

Wednesday, February 11, 2015

..........The well of Saint Geneve



In 1245, Innocent IV issued bulls and sent an envoy in the person of Giovanni da Pian del Carpine (accompanied byBenedict the Pole) to the "Emperor of the Tartars" The message asked the Mongol ruler to become a Christian and stop his aggression against Europe. The Khan Güyük replied in 1246 in a letter written in Persian that still rests in the Vatican Library, demanding the submission of the Pope and the other rulers of Europe.



The well with pulleys