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kiram9

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I grew up fixing electronics and learning from those engineers who designed stuff that broke. Now I get to design products every day and I love it!

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The US Grid is split into three relatively unconnected grids, east coast, west coast, and texas. Each section has one plant designated to keep the frequency, sort of a "master plant" that is used to balance instant load. All of these are synchronized across the US using phaser measurement units that are timed to GPS.

The other cool thing about AC power is that you can send power based on the relative phase of a node on the grid. This means that a node at a lower AC voltage can send power to another node at a higher voltage by adjusting the relative phase. Mostly this is done by switching capacitor banks at various transmission nodes to adjust the reactive power component at that node.

There is a standard to keep time on LANs now: IEEE-1588 which is built into a lot of new network cards. It enables the NIC to time stamp incoming packets which can be used to achieve sub microsecond timing.

Normally it can be implemented with a single GPS receiver on the network that then feeds all servers/devices. It is starting to become very common in broadcast applications as a reference. Furthermore most manufactures already offer some application notes/libraries to make use of it. And linux offers PTPd which implements the standard.

http://ptpd.sourceforge.net/

http://en.wikipedia.org/wiki/Precision_Time_Protocol

http://www.nist.gov/el/isd/ieee/ieee1588.cfm

One of the traditional big inhibitors for laser projection in the USA is the FDA. Previously any public venue that uses laser projection requires special certification to operate which prohibits many theaters from rolling out these projectors. See: http://www.barco.com/en/News/Post/2014/4/15/US-FDA-product-v...

I am excited to see the technology progresses. Including expanded color spaces that can handle projection of higher dynamic range images with brighter highlights. Some of the new UHD standard proposes a new color space that will allow the dynamic range to increase dramatically. However lots of standards are coming out that should replace some of the existing digital standards such as BT.709 (HDTV) or perhaps even surpass BT.2020 with more dynamic range!

my optimus card in my w520 works perfectly in 14.04 - and there are task bar widgets for switching now (logout required). After installing 14.04 my external monitors and display switching work perfectly! I was really happy as I was stuck with a non functional gfx card in linux for a few years and now it finally works.