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AT Black Knight Transformer Hits the Road and Takes a Hop

strack electric (33 comments)

Why would you not have just one bigger engine powering a generator, and electric engines for the rotors and wheels?

about a week ago
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NASA Halts Non-ISS Work With Russia Over Ukraine Crisis

strack Re:"needs to end" (291 comments)

The current administration has bloody well succeeded by waiting for commercial manned spaceflight to fill the role. And trust me, the Shuttle needed to die. It was a politically compromised design which led to it being expensive and unsafe. And if the current administration didnt sit on their hands, any crew carrying rocket they made would probably squeeze the likes of spacex out of contention. Not on price or efficiency mind you, but on government mandated usage by NASA. Much like the shuttle did for 30 years.

about two weeks ago
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U.S. Court: Chinese Search Engine's Censorship Is 'Free Speech'

strack fair enough (284 comments)

Yeah. They to have the right to censor their search results if they want to, being a private entity in the U.S. Though, if they don't make clear that they are censoring search results, then I imagine they open themselves up to being sued for false advertising if they claim to be a 'internet search engine'.

about three weeks ago
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Anti-Game-Violence Legislator Arrested, Faces Gun Trafficking Charges

strack Re:What party was that again... (234 comments)

So thats a study that says that psychologists discriminate against colleagues with conservative views. I dont understand how that translates into "hatred against white Christian men". Seems they just dont like collegues with a political view that supports creationism over evolution in schools, ignorance of climate change research, and a general anti-science bent in their policies. Sounds like scientists being rational actors.

about three weeks ago
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Eric Schmidt On Why College Is Still Worth It

strack Re:Mod parent up! (281 comments)

Am Australian compsci grad, can confirm. Its called HECS
P.S. you guys are getting fuuuuuucked.

about a month ago
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The Era of Facebook Is an Anomaly

strack Monopoly (260 comments)

It appears that MS disapproves of monopolies and lock-in in proprietary systems when there not the ones doing it. Worlds tiniest violin etc. etc.

about a month ago
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Sulfur Polymers Could Enable Long-Lasting, High-Capacity Batteries

strack Re:Dat envelope (131 comments)

well its true, i dont know the conversion from mah/g to kwh/kg here, but im going on that 1005mah/g figure stated, and its comparison to the 200mah/g for a current lithium ion battery. and im being conservative, using the 4x multiplier instead of 5x. And since they say charge-discharge cycles, i presume they measured the energy coming out of the battery.

about a month and a half ago
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Sulfur Polymers Could Enable Long-Lasting, High-Capacity Batteries

strack Re:Still a ways to go...until we get where? (131 comments)

well, you attached your name to some sarcastic pablum, and it still didnt make it worthwhile to say. But hey, at least now you know 1 more thing than you did before. have a gold star.

about a month and a half ago
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Sulfur Polymers Could Enable Long-Lasting, High-Capacity Batteries

strack Re:Dat envelope (131 comments)

actually, i should probably lop off about 30km range to account for energy losses from the electric engine.

about a month and a half ago
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Sulfur Polymers Could Enable Long-Lasting, High-Capacity Batteries

strack Dat envelope (131 comments)

Lets see what the range on a typical light aircraft would be if you ripped out the full fuel tanks and gasoline engine and stuffed it with a equivalent power electric engine and these new batteries to the same weight. So it says it will store 4-5 times as much energy as todays best lithium-ion batteries. the best li-ion today is lithium cobalt, at about 165 wh/kg. So x4 of that is 660 wh/kg.

now, lets take a light plane for which I can find enough info to do this with, the jabiru j160D ok. so the fuel in it weighs (135L * 0.72kg/L) = 97.2kg. Now, the engine in it, the Jabiru 2200cc Aircraft Engine, weighs 62.8kg, and has a max power output of 60kw, and cruises at 75% power, so lets assume 50kw cruise power to account for takeoff and landing. So in total, engine and fuel weight 97.2 + 62.8 = 160kg

so lets rip that 160kg out and replace it with a EMRAX228 Brushless AC electric Motor with a 100kw power output and weighing in at 11.9kg, leaving us 148.1 kg worth of batteries, with a energy storage capacity of 148.1 * 0.66 = 97.746 kwh. so, at the cruise speed of 100knots = 185.2km/h, your looking at a range of (97.746kwh / 50kw) * 185.2km/h = 362km in about 2 hours.

The gasoline version can fly at the same speed for 8.5 hours. So, sure, the range is a quarter of the gasoline one, but you could ditch a passenger, chuck another 100kg of batteries in there and get that up to about 3.5 hours and 630km of range. Pretty damn good for a few dollars of electricity, negligible maintainence costs on a electric engine vs gasoline engine. sure as hell beats the $100+ youll pay for fuel alone for that same 3.5 hour trip.

about a month and a half ago
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Sulfur Polymers Could Enable Long-Lasting, High-Capacity Batteries

strack Re:Still a ways to go...until we get where? (131 comments)

Um, what? Specific energy is wh/kg, and is much more important than the amount of volume the battery takes up. Pushing extra battery weight around takes more energy, extra volume isnt that hard to deal with.

about a month and a half ago
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Sulfur Polymers Could Enable Long-Lasting, High-Capacity Batteries

strack Re:Still a ways to go...until we get where? (131 comments)

If you get it to the point that you can drive the car all day on a full battery, the "overnight" part wont matter so much.

about a month and a half ago
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Sulfur Polymers Could Enable Long-Lasting, High-Capacity Batteries

strack Re:Still a ways to go...until we get where? (131 comments)

I guess he doesn't know. I imagine there's a lot of things he doesn't know.

about a month and a half ago
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Sulfur Polymers Could Enable Long-Lasting, High-Capacity Batteries

strack Re:Still a ways to go...until we get where? (131 comments)

Don't forget that gasoline engines typically turn only about 20-30% of the chemical energy into mechanical energy, whereas electric motors are about 90%. And you get rid of a heavy gasoline engine.

about a month and a half ago
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SpaceX Testing Landing Legs On Next Falcon9 Rocket

strack Re:SpaceX (73 comments)

Thats adorable. "a whole 2 launches!". Meanwhile the grasshopper VTVL test rocket did 7 jumps, while using a merlin D engine. This isnt your daddys shuttle main engine.

about 2 months ago
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SpaceX Testing Landing Legs On Next Falcon9 Rocket

strack Re:SpaceX (73 comments)

Elon Musk has stated in the past that "a little seawater" wouldnt harm the engines.

about 2 months ago
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SpaceX Testing Landing Legs On Next Falcon9 Rocket

strack Re:SpaceX (73 comments)

Are you sure about that reconditioning? your comparing it to the space shuttle engine, that needed to be torn down, inspected, and rebuilt after every flight. But that was because it was built to razor thin engineering tolerances. The merlin engine is quite a bit more durable.

about 2 months ago
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First New Generic Top Level Domains Opening

strack why do we need generic top level domains anyway. (198 comments)

why do we even have .com or .org or .net on the end. Surely the classification of organization at a address can be stored in some other way, and not be so important as to need to be typed in every time you go to that url. I mean, why cant i just type 'slashdot' in the address bar. Damn near everyone defaults to .com anyway.

about 3 months ago
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Doctors Say Food Stamp Cuts Could Cause Higher Healthcare Costs

strack Re:As someone on food stamps... (1043 comments)

Its so fucking awesome that we have a enlightened individual such as yourself to convey these revelations to all the poor people. Well apart from the fact that per calorie, processed and sugary drinks cost less. If your gonna be a sanctimonious, patronizing ass, the least you could do is be not wrong.

about 3 months ago

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