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Comment: Intern at JPL, hang out in Mojave (Score 1) 283

by DesertNomad (#37813370) Attached to: Ask Slashdot: How To Enter Private Space Industry As an Engineer?

RPI is a fine school, you'll find plenty of company. Or, find a way into Caltech. JPL is a long way from your 5-hour radius, but you actually have the opportunity as an undergrad to get involved in some cool-ass stuff. JPL is a mechanical engineer's paradise, those of us who are EEs get treated OK %^).

Comment: "Hi I'm Stanley the Speed Limit Sign..." (Score 1) 115

by DesertNomad (#36782752) Attached to: Ford Demonstrates Networked Cars

"... and you are exceeding the posted speed on this highway. Your vehicle ID has been logged, and your vehicle is now being rerouted to McDonalds indicated here, "where America is lovin' it", and you will be served with a notice of infraction as well as a discount on a cup of McCoffee (limit one per violator)."

The US DOT Intelligent Transportation Systems (ITS) Program has been going on for a very long time. It's taken at least half a decade just to get to the point where there are some practical standards.

It's not your average basement-dwelling Slashdotter's Wi-Fi - this is 802.11p in the 5.9GHz band, the work for which was only completed last year.

Will be licensed restricted access, between vehicles and roadside infrastructure like talking signs and signposts, warning devices, all that happy stuff. Perhaps using multihop, traffic jams and accident scenes could get propagated out to allow motorists to recompute route before becoming mired. No one has figured out how to pay for it or what it will really do. At least in the past, there was talk about commercial organizations subsidizing the infrastructure in return for being able to advertise their service/location on the vehicle's nav system.

Comment: Morse Code over 50 LY path! (Score 1) 343

by DesertNomad (#35938182) Attached to: Brainstorming Clever Ways To Detect Alien Civilizations

Typical deep space comm channels run into the Ka-band spectrum (26-40GHz). The path loss at 32 GHz, between the two stations separated by 50 LY, is an unimaginably large 416dB. Taking the largest fully steerable dish on earth (DSN 70m dish), running at a communications frequency of 32GHz, 400kW transmitter output, and a communications bandwidth that's good enough for 20 word-per-minute Morse code, one could theoretically close the circuit between an identically equipped station 50 LY distant. You could possibly signal somewhere around 300 baud hayes modem speeds circa 1980 if you really worked at it.

Comment: Re:This is why "health insurance" is so expensive (Score 1) 138

by DesertNomad (#35108436) Attached to: Algorithm Contest Aims To Predict Health Problems

Very few medical conditions are caused purely by lifestyle choices...

You'll need to show a little proof here.

On the other hand, "Personal decisions are the leading cause of death", Dr. Ralph L. Keeney of Duke University, 2008

A discussion of his paper, with a variety of points of view, at the Operations Research Forum

And for the rest of us, the Wired article on his paper is here

Comment: Recursive self-limiting (Score 1) 305

by DesertNomad (#35099348) Attached to: Verizon To Throttle High-Bandwidth Users

Nice idea, and one that is auto-ratcheting, with the ultimate effect to drive data volumes down all across the subscriber base. This month, the top 5% get throttled. Next month, the next lower volume tier may now define the top 5%, and that gets throttled. Ultimately, data volumes approach zero, and someone still gets throttled because there's always a top 5% who are the worst. And all along, Verizon can claim it's only the worst bandwidth users getting punished. It's like the system we use here at work to get rid of the low performers... There's always a bottom 10%!

Comment: Re:Bluetooth is gone eh? (Score 3, Informative) 78

by DesertNomad (#34020856) Attached to: Wi-Fi Direct Gets Real With Product Certification

Actually, Bluetooth 3.0 uses IEEE802.11, not Wi-Fi, as the underlying carrier technology. Wi-Fi is a superset of 802.11 features. Wi-Fi brings broad interoperability, higher level functionality and mandated conformance to established standards. BT 3.0 uses 802.11 as an Alternate MAC/PHY (AMP) layer, has a fixed signaling rate of 24Mbps, and does the "networking" using the BT radio and BT protocols, not Wi-Fi. It is not necessary for a 802.11 radio that is set up to run in BT3.0 mode to be compatible with a standard Wi-Fi access point, as BT3.0 is really supposed to be used to allow higher speed data transfer (about 8x) between two BT3.0-enabled devices, like a cameraphone and a notepad. Wi-Fi Direct is direct competition to BT 3.0, but does it more simply with the one radio, technology and protocol rather than two radios and a mix of protocols that are very different and more costly.

As some of you might remember from way back in 2005, originally the high-speed AMP was going to be Ultrawide Band (UWB), but the BTSIG took a bet on the WiMedia Alliance's MB-OFDM quasi-UWB technology and lost when WiMedia folded its tent in early 2009, after probably a dozen manufacturers had failed to get MB-OFDM silicon to work as promoted.

Bluetooth is not gone, in fact BT Classic (the 2.1 stuff) is in the majority of all cellular handsets sold in the world today, and I think each week something like 20 million BT chips are shipped in product, 90++% of that in cellular handsets and headsets. However, the actual usage of BT is pretty low since most people don't really seem to take to headsets, or if they do use a headset, it's often wired since that eliminates the need to charge two batteries. Like I saw somewhere else, BT seems like the IRDA of the 21st Century, ubiquitous yet little used

That having been said, Since 2004 or so I've been using BT headsets (5-6 models now), multiple BT-enabled phones, even a BT-enabled PDA (remember the old Sony Clie), and am generally satisfied by the convenience and performance. Pairing has gotten way better with 2.1, my phone (BB) only forgets about my headset (Jabra) every second week or three, requiring a repairing effort. But I'm an engineer, and have some tolerance for touchy gadgetry... And no, I'm not a member of either the BTSIG or the Wi-Fi Alliance.

Comment: The end of the Bio Break? (Score 1) 434

by DesertNomad (#33799994) Attached to: Google Patent Proposes $2 Fee To Skip Commercials
In the good ol' days, that 10 minutes of commercials before would allow me time to hit the head, make a sandwich, grab a beer. But, I'm sure they'd make it so that the view time would be **interactive**, so I'm going to have to train my robot monkey to hit the mouse button the exact number of times required to get through that 10 minutes. Well, I guess that's an opportunity for new business!

Comment: Re:Top Speed ? (Score 5, Informative) 229

by DesertNomad (#32934056) Attached to: Ikaros Spacecraft Successfully Propelled In Space
Barely distinguishable? Jupiter is only 5 times Earth's distance from the Sun. Outside Earth's atmosphere, solar insolation averages around 1370 watts per square meter. At Jupiter's orbital distance, it's about 50 watts per sq meter. That's a huge amount of power. At Jupiter's distance, the Sun is well over a million times brighter than Sirius, the brightest star in the Terran sky. Barely distinguishable? Bah.

Comment: Re:Cheaper astronomy (Score 4, Informative) 59

by DesertNomad (#32397898) Attached to: SOFIA Sees Jupiter's Ancient Heat
Um, they do and do so regularly. Balloons hoisting 2000kg+ payloads, up for weeks at a time, at elevations over 30-35km. When working in the 90's at JPL in Southern California, I would occasionally have lunch with a guy responsible for launching huge skids of scientific equipment at Palastine, TX, at the National Balloon Facility. Palastine is convenient due to the large amount of helium produced as a waste product from the wells in the area. Palastine's accomplishments notwithstanding, Southern California is also home to cutting-edge balloon experimenters.

Comment: Re:1st (Score 2, Informative) 63

On any standard XGA and higher-res LCD display, there's a fair chance that at least one pixel has a problem of some sort. Each OEM has their own QA guidelines which they really don't want to share unless you push. This site gives some idea of the thresholds.

Speed of a tortoise breaking the sound barrier = 1 Machturtle