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Comment: Re:is it an engine or a display model? (Score 1) 54

by Rei (#49148083) Attached to: Researchers Create World's First 3D-Printed Jet Engines

Microturbines are one of those few things where 3d printing might actually prove an economical means of production - the keys being small, intricate, and very expensive.

I wonder how effective it'd be to print out one of these, minus the windings. They've got crazy power output (up to 100kW sustained / 200kW peak) and efficiency (up to 98%) in a motor small enough (20kg; significantly less without the windings) to make a 3d printing service (or more realistically in this case, a custom CNC milling service) cost effective. Buying them commercially, they're something like $4k USD each. But there's a 3d model available, so....

All I can say is, I'd love an electric car with one of those driving each wheel....

Comment: Re:is it an engine or a display model? (Score 2) 54

by Rei (#49147893) Attached to: Researchers Create World's First 3D-Printed Jet Engines

Laser sintering of titanium is a well established process and should produce excellent turbine blades. 3d printing plus thermal spraying (a new one I've seen uses a form of laser spraying) might actually be able to produce parts better than would be possibly by any other means (such as machining cast metal) because you're not only heating the grains to join them together, but compacting them at high velocity.

Even for the more "primitive" 3d printing metal techs, they're just lost wax casting where the original mold is 3d printed. So the results are no worse than any other lost wax cast metal.

And yes, I was hopeful that this was a fully finished, working product. And that I'd be able to download the model. There's little that I'd be willing to pay the premium of laser titanium sintering for, but a micro jet turbine is one of those things. ;)

Comment: Re:Like some baby bees with that? (Score 2) 128

by Rei (#49135489) Attached to: Inventors Revolutionize Beekeeping

It's an American thing

And anyway, given how the device works, the concept that baby bees if present are going to flow out doesn't sound realistic. The device robs honey by opening up a small rift in the plastic comb that honey can slowly trickle through. Unless we're talking microscopic baby bees here, I can't see them passing through with the honey.

Comment: Re:Fad Ahead? (Score 1) 128

by Rei (#49133325) Attached to: Inventors Revolutionize Beekeeping

I live in a country where beekeeping is juuuust starting to take off. The prevalence of diseases - at present - is probably little to none. And we're highly geographically isolated. So if disease and pest control is normally the biggest challenge, then we've got that taken care of (our main challenges here are cold, windy weather and a long winter; supplimental winter feeding is a must)

Comment: Re:What would a Nurse Do (Score 5, Funny) 162

by Rei (#49128075) Attached to: Should a Service Robot Bring an Alcoholic a Drink?

The summary did call the person in question the robot's owner.

I think the robot should obey the owner's wishes and get them the drink. But it should sigh audibly when asked to and mumble under its breath while giving it to them. Maybe occasionally snipe at them in a passive-aggressive manner. "Should I cancel all productive activities that you had scheduled on your calendar for today?" "Would you like vodka in a glass or should I set it up as an IV drip into your arm?" "Would you like me to make a bunch of regrettable drunken Facebook posts for you, or would you rather do it yourself?"

Comment: Re:Not very effective. (Score 1) 132

by Rei (#49118055) Attached to: Pakistanis Must Provide Fingerprints Or Give Up Cellphone

I would agree in general but I see a big potential loophole. What about foreign sim cards? Does Pakistan plan to apply the same restrictions to people who visit the country? If so then I would think that this might provide a significant hindrance to international tourism and trade - "no cell phone for you unless you go register it with the government while you're here!" On the other hand, if they don't do it, then lawbreakers will just get foreign sim cards.

Maybe the government could make a fairly painless process for foreign visitors.. for example, sim card registration at the point of entry to the country, for those willing to do it (and for those not willing to, they just can't use their phone).

I thought about other potential loopholes, such as phone / sim card theft, but one presumes those cards would be rapidly disabled when reported. A rather nasty possible workaround to the problem would be to kidnap and murder people, steal their phones, and continue making payments in the deceased's name until someone catches on. That could of course carry a risk that if someone did catch on, instead of disabling the stolen phone they may just use it as a beacon to catch you. Satellite phones would work, of course, but they're a lot more expensive, both in terms of hardware and service. And someone not associated with the government in Pakistan using a sat phone is probably as it stands immediately be flagged on the watch list of anti-terrorism task forces the world over.

Comment: Re:Changing for you maybe (Score 2) 420

by Rei (#49111079) Attached to: What If We Lost the Sky?

Quite true. Last spring I went to the US (Indiana and Texas) from Iceland with my then-fiance to show him where I grew up and went to school (he grew up in Iceland). It was too bright for him in Indiana, and in Texas it was downright painful for him.

We don't get much of that "sun beating down straight overhead" stuff here that you get in the states, it more sort of rotates around you, with really long sunrises / sunsets (sometimes with multiple sunrises / sunsets in a day as it moves past mountains).

Comment: Re:Changing for you maybe (Score 1) 420

by Rei (#49111025) Attached to: What If We Lost the Sky?

Waaah. I live in Iceland, don't complain to me about a lack of winter sunlight.

I wasn't excusing anything - I don't support any geoengineering that works by increasing the albedo, for many different reasons. But it's simply fact that a large portion of the world's people live in areas that get proportionally little sun. And contrary to myth, they don't have higher suicide rates or anything like that.

The US (where many if not most slashdotters live) is actually an unusually sunny country, by first-world standards. Even Seattle is sunnier than Berlin, which is sunnier than London, which is sunnier than Glasgow...

Comment: Re:Changing for you maybe (Score 5, Informative) 420

by Rei (#49110739) Attached to: What If We Lost the Sky?

Yeah, a lot of people already live in the sort of environments that they're warning against. This line got me:

And the sky is one of the few sources of that experience that's available to almost everybody

Is that a joke? People's ability to see the night sky varies vastly depending on where they are. In big metro area, all you can see are the brightest of stars. There's little to no majesty to it. It's when you get out into the deep, deep countryside and look up at the uncountable multitude above you that you feel little and insignificant compared to the cosmos around you. There's nothing universal about ready access to a dark sky. And it's getting rarer and rarer.

Comment: Re: Umm... Lulz.... (Score 1) 253

by Rei (#49110593) Attached to: Will Greek Finance Minister Varoufakis Support Cryptocurrency In Greece?

If they create an exchange with a current crypto currency and conver all their money to it except what is needed from day to day, then drop out of the Eurozone and create their own dollar, each crypto dollar will be the value of the crypto currency used.

Sorry, but unless there's hard assets behind it, it's going to float. And the float will be way down, just the same as any other Greek currency. Greece's creditors and exporters don't want New Drachmas, CryptoDrachmas, or anything of the sort: they want dollars and euros. To get dollars and euros, Greece has to make and export goods and services at a rate competitive with their rate of imports. For their government to get dollars and euros, they actually have to stamp out corruption, tax evasion, and so forth. Greece's inability to do these things is the reason they're in the bind they are today.

Comment: Re:How useless is Slashdot (Score 3, Interesting) 33

by Rei (#49110531) Attached to: Rocket Flown Through Northern Lights To Help Unlock Space Weather Mysteries

You mean this article? Albeit the summary was poor, but it covers the firmware hacking.

And FYI, if anyone actually takes the time to read the Kaspersky report they'd catch that the infection is believed to have been done on thousands to tens of thousands of computers, NOT "most HDDs". The firmware has the capability to infect most HDDs, but most HDDs are not infected - according to the very source report itself.

Which should be obvious. Because if you're the NSA and you're writing a super-infection to use against top-level targets, the last thing you want to do is have it on every last computer in the world, increasing your likelihood of being found by many orders of magnitude. The NSA's preferred method of infection is interdiction - intercepting objects while in transit to targets, such as CDs or hard drives, infecting them, then letting them continue on their way.

Once again, the NSA doesn't give a rat's arse if you're going to the Pirate Bay to download I Am Legend. It has far more important things to worry about, like people building atomic bombs and invading other countries.

Comment: Re: Umm... Lulz.... (Score 2) 253

by Rei (#49108551) Attached to: Will Greek Finance Minister Varoufakis Support Cryptocurrency In Greece?

Whatever they convert it into, New Drachmas or Cryptodrachmas, it's still going to devalue like crazy. Both, being backed by the same entity (the state) will have the same credibility problem. Except even moreso for the cryptocurrency because of all of the concerns that carries with for many investors.

Nothing is more admirable than the fortitude with which millionaires tolerate the disadvantages of their wealth. -- Nero Wolfe