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Wireless Networking

LA's Smart LED Street Lights Boost Wireless Connectivity ( 75

An anonymous reader writes: Los Angeles will introduce a smart street lighting system, featuring connected LEDs and fully-integrated 4G LTE wireless technology. In a collaboration between Dutch tech firm Philips and Swedish telco Ericsson, the SmartPole project aims to deliver LA citizens public lighting which is energy efficient and improves network performance in urban areas. By the close of this week, a total of 24 SmartPoles will be installed across the Hollywood area. The city plans to place 100 poles over the coming year, with a further 500 to follow.

Comment Re:"Industrial design student" (Score 1) 167

Option 1 would be consistent with much of my previous experience, if you change out "morons who also don't know" for "enthusiastically naive people who don't pause to consider." "Design" projects emphasize concepts and pretty pictures over execution, cost effectiveness, and practicality, and many of the most severely hyped ideas from that community run the gamut of unworkability from "merely completely impractical" to "would need to reverse basic physics."

Comment "Industrial design student" (Score 5, Informative) 167

Apparently the industrial design curriculum doesn't cover thermodynamics. Condensing water at room temperature requires shedding about 680 watt-hours of energy per liter, and thermoelectric coolers tend to burn off more than twice the energy they pump (depends on a few variables, but practical devices in practical situations usually fall in that ballpark). You'd need somewhere near a constant half-kilowatt to provide for one person's normal water consumption. Much more if they're exercising or in a hot environment.

Comment A thousand dollars? What the hell. (Score 1) 48

If you blow a grand on flying just a camera and tracker, you're doing something amazingly wrong. I worked on a university project that didn't cost that much, and we flew two expensive radios, a SPOT tracker, APRS tracker, Arduino Due flight computer, HD video camera, two GPS receivers, an active thermal control system, and a Kerbal, and we went into it not really knowing what the hell we were doing.

With one flight's worth of experience under my belt, I could put together a decent tracked payload with sensors and a camera for under $200, using off-the-shelf components. Less if I want to spend time making a circuit board. I'm not sure what helium costs these days, but that and a small envelope sure as hell aren't going to add $800 to the bill.

Comment Re:An EMP from a super solar flare... (Score 1) 151

Are you saying that writer doesn't know what he's talking about?

That is exactly the case. There is an infinitesimal kernel of truth at the center of that pearl of idiocy; a high-altitude nuclear detonation does produce geomagnetic field disturbances similar to, but much more violent than, a CME impact. But the effects one normally thinks of as coming from a nuclear EMP -- small electronics being suddenly destroyed by radio-frequency electromagnetic fields -- are absolutely absent from a CME-induced geomagnetic storm.

Comment Re:Backup My Data (Score 2) 151

Or, y'know, be underneath a nice, thick atmosphere. You're absurdly exaggerating the penetrating capability of solar protons. The ones in the CME that will hit on Friday aren't even very energetic, and the MeV scale protons are already here and starting to fade out after a thoroughly unremarkable S1 radiation storm.

Comment Re:"float down on Europa's atmosphere" (Score 1) 79

There's another possibility that occurred to me: That the actual mission concept does incorporate measures to address those problems, including propulsion on the chipsats, but was so magnificently mangled by the press office and reporters as to create the appearance of complete crackheadedness. This would require a slightly greater-than-usual commitment to misrepresentation and intellectual laziness on the part of the journalism majors, but is within the realm of plausibility.

Comment Re:"float down on Europa's atmosphere" (Score 1) 79

Trust me, no scientist at Draper spent months on this. It would make some damn sense if they had. It reads like a summer intern's wide-eyed ramblings after they just read about things other cubesats have done, but before they considered any of the actual engineering issues.

And sometimes, you end up with a random /.er who, though the satellite he's working on is only going to low Earth orbit, sees the potential of applying the cubesat fast/cheap/high-risk philosophy to interplanetary missions, had already quantified the problems with power generation at Jovian distances from the sun and the resources required to communicate with a miniscule power budget, and even went and read about the possibility of common materials surviving unshielded reentry a few years ago when the chipsat idea started making headlines.

There's real potential for using cubesats beyond Earth orbit. Lots and lots of people have noticed this, and they've generally also noticed the same set of problems -- power, cold, communication, and radiation. There are possible solutions to each of those, but they come with major costs and the probe described and drawn in the article incorporates none of them.

The aerodynamic entry idea is utter nonsense on that moon, though -- what passes for an atmosphere on Europa would qualify as "ultra-high vacuum" in a laboratory. It's about the same density as what the ISS is orbiting through right now. There is no structure in existence that could decelerate enough in that atmosphere to land gently. The terminal velocity of a flake of monolayer graphene is comparable to rifle muzzle velocities, and functional circuitry is a few orders of magnitude heavier than that.

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