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Comment Re:Want to know the truth about Skype? Read on. (Score 1) 150

CALEA's "Second Report & Order" states it's providers that must foot the bill. If our government paid for MS to acquire Skype perhaps there are shady deals afoot, but the US law states providers must pay the costs of snooping: the aforementioned shady deals would be very bad behavior from the US of A government, paying to acquire CALEA compliance.

The costs of running a couple thousand Linux nodes & paying bandwidth can not be that bad. MS certainly knew they'd have to remake Skype when they bought them, that the old P2P structure would have to go. I would want to think no grand conspiracy was involved, that what happened, the remodeling to a snoop-friendly infrastructure was simply due. It will be interesting to see going forwards, with the tentative thumbs up given to Skype plus the upcoming WebRTC technologies, how CALEA enforcement can be maintained: WebRTC certainly suggests decentralized models, although of course STUN & the various tunneling protocols are ripe for deliberately avoiding the easiest P2P routes & tunneling through glassboxes.

Comment JWST, Mass (Score 2) 224

Yet another place the JWST (James Webb Space Telescope) would be fantastically useful!

Also, how seriously would the presence of previously undetectable ultra-cool stars affect the search for dark matter? Aren't we looking for energy/matter based off some energy level, and might that mass be tucked away in the form of ultra-cool stars, just to cool to detect?

Comment rhel/SPICE (Score 2) 498

http://www.redhat.com/virtualization/rhev/desktop/spice/
http://www.spicespace.org/

it's pretty aggressive. just found out about it a couple months ago. QEMU based. they're doing some cool stuff with virtual devices; qxl is their accelerated graphics driver for Linux & Windows, and is probably gonna end up taking over for NX client now that they're closed source. and yes, i am aware there is a difference between a remote desktop and vm.

interested to see how RHEL manufacture disk images for the individual clients; needing a dedicated disk image for each OS is pretty bogus, but fairly common practice.

Comment axial flow (Score 1) 570

a normal two stroke has recirculating air in the combustion chamber. when you exhaust you dump some fuel. when you intake you mix with existing fuel/air. air is coming and going from the same general area.

axial flow is the key to opposing piston. the chamber is shuffling a little forwards and backwards in opposed piston design, exposing intake and exhaust ports at opposite ends of the chamber. since air is moving in a net direction, circulation can be much more tightly controlled. there's huge potential to get air behaving according to design and engineering wishes-- the trick, the reason these guys are spending money and this hasnt taken over already, is that this timing is incredibly difficult and exacting. if done right, you get a two stroke that breathes as well as a four stroke. it's just not easy.

opposed piston's been championed for high efficiency and high power density since the 1950's. this is why. given the tooling we now have at our disposal to understand complex factors like airflow and thermal dynamics, it should be no surprise these things are gonna see a huge resurgence.

Comment Re:Titanium horseshoes (Score 1) 570

i agree on everything except your conclusion. yes this is old tech. wikipedia lists examples as far back as 1907: http://en.wikipedia.org/wiki/Opposed-piston_engine .

however it's old tech that was the leader in power density and efficiency, right up until they got upstaged by gas turbine. axial flow keeps air moving in one direction and not recirculating, which can go a huge way to mitigate the down sides of the two stroke design, while playing to two strokes natural power density advantage. coupled with increased kinetic capture (% of combustion surface which is piston v. chamber), opposed piston makes a lot of sense.

as far as replacements go, the only viable example i can think of is Fuel Cell, and frankly we arent energy rich enough to throw power away compressing and processing inputs to supply ourselves with a fuel replacement. fuel cell will make more economic sense in fifty years when petrofuels are expensive and grid power is cheap. for now, we have nearly a billion vehicles on the road and doubling the power/weight and fuel efficiency of the next ones we build makes a lot of sense.

also, power density has it's own merits at times, and these are unparalleled, being extremely efficient two strokes.

the fact is ICE has a lot of life left, and a lot of strengths. given that absolute 100% fact, this tech is sensible and ought be pursued.

Comment history downscaled (Score 2, Interesting) 570

Yes opposed piston is an old idea. For a time they were popular for high power density applications, and high efficiency applications (awesome axial flow properties). The reason this old creation fell out of favor is that, for the high-density extreme-efficiency uses fulfilled, there was an all around better replacement: gas turbines.

Gas turbines, however, have their own host of issues which make them unsuitable for all applications. Captone's 30kW microturbine, for example, is itself small, but has a sizable host of systems to support it and deal with the high temperatures, and costs a decent fraction of a million dollars last I checked. It and it's upsized bretheren are found in buses, and the occasional exotic-- see the CMT-380: a car custom built around the sizable & demanding microturbine power plant.

Given the challenges of using gas turbines, EcoMotors opting to dust off and enhance the next best thing makes some sense. There's big opportunity to evolve this already uber efficient two stroke's airflow with modern techniques and tooling. You've pointed out a number of mechanical challenges, but these seem to me considerably more mundane than the challenges of adapting a gas turbine to an every day machine. It may be old tech, but it's considerably better than what powers nearly a billion motorized vehicles on the roads and in the fields today.

I'd say the revival is both well timed and worth pausing to examine. Please feel free to contribute alternative reasons for their having fallen out of favor; would be most interesting to collect more facts or anecdotes.

Comment gratuitous waste and DLNA alternatives (Score 1) 171

i would've much rather someone developed a UPnP/DLNA realtime screen encoder, and then have used something like WiGig to wirelessly shuffle that completely bog standard DLNA stream to whatever series of displays it needs to go to. i'm sure there are advantages to one off'ing a wireless protocol, but i'd rather have had a standard for generic wireless communication, and a separate standard for system to system media sharing. all that really was needed to make that possible was, as i've said, realtime encoding of the screen into a DLNA compatible stream. that would've been much more flexible: any UPnP/DLNA device could consume the stream, assuming it has enough bandwidth to read all the bits. instead, you have to go out and buy dedicated transmitter and receivers just for this. truly a gratiutous waste of wideband, and media streaming.

Comment WiDi (Score 2, Interesting) 171

keep in mind, WiDi requires an Intel Core processor and special software on the computer doing the realtime encoding. Can anyone confirm whether Wireless Display is compatible with the existing spec called Wireless HD? Wikipedia forwards WiDi to WirelessHD, but my understanding was Intel's spec was not inter-compatible.

Comment Re:That's Expensive (Score 2, Insightful) 208

1% of Google's CPU load.... that's 1% of the biggest collection of the largest data centers on the planet. Find a real metric for SSL cost, including any additional latency full end to end induces on each request, or GTFO.

Conversely, people saying "it's expensive" should have some numbers as well. Both on cpu utilization, request latency, effects on http pipelining, &c &c &c. SSL has numerous "costs", including places where full end to end encryption is not permitted. Ultimately the argument that seals the deal is the last one: this is an authentication problem, a trivial MITM attack; that doesnt require end to end encryption, that just requires authentication (see: Kerberos). Cookies, by themselves, just happen to not cut it there.

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