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Comment Re:200 cycles? (Score 3, Insightful) 132

On the other hand, if they're doubling capacity, then you only need half the number of cycles (it actually even works *better* than that, as li-ion cells prefer shallow charges and discharges rather than deep ones - but yes, fractional charge cycles do add up as fractional charge cycles, not whole cycles). If you have a 200km-range EV and you drive 20 kilometers a day, you're using 10% of a cycle per day. If you have a 400km-range EV and you drive 20 kilometers a day, you're using 5% of a cycle per day.

Comment Re:well then (Score 5, Insightful) 132

Top commercial li-ion capacities are about 30% more than they were 5 years ago. And today's batteries include some of the "advances" you were reading about 5 years ago.

I'm sorry if technology doesn't move forward at the pace you want. But it does move forward when you're not looking. Remember the size of cell phone batteries back in the day?

Comment Also lower power for performance (Score 1) 138

Intel's chips have been real good in terms of performance/watt these days. AMD has had real problems in that regard. Their high end chips are massive power sinks. Now in some uses, maybe that isn't important, but in a small system, it matters. You are going to have to jump though hoops to make sure you thermal system fits, is sufficient, and isn't loud anyhow, trying to put a ton more power in there isn't a winning idea.

Thus when you have the 4790k on the one hand, which is rated at 88 watts TDP, and the AMD AMD FX-9590 at 220 watts on the other hand, the choice is pretty clear. Even if performance were equal (it's not) the power savings is a clear win for a small unit.

At the moment a combination of older lithography technology and core design has AMD CPUs running pretty high power, so not the thing for SFF devices. Perhaps that will change with their next generation, we'll see.

Comment Ya pretty much (Score 1) 177

You can argue for or against various licensing, insurance, bonding, etc requirements but what it comes down to is they need to be consistent. If a given type of work has that requirements, then everyone needs to be held to it, or it needs to be removed. You can't have it where some people have to jump through the hoops, but others don't.

A more extreme example would be pharmacists. To be a pharmacists requires a great deal of training and certification, in the US at least. That is how it is: You wanna dispense prescription medication you have to have the right degree, and experience and certification. Well, we can't very well have that but then also allow someone to be a "medicine sharing service" that just has random uncertified people who dispense medications. I suppose you could argue drug dealers are that and, what do you know, the government will put them in jail.

So if you think the licensing requirements for taxi services are silly, fair enough, let's work on getting rid of them. But Uber and the like shouldn't get a pass whereas traditional taxi services have to comply. Either is is a requirement or it isn't. It should have to do with the type of work you do, not the name of the company you work for/with.

Comment From TFA: (Score 4, Insightful) 213

Taubira doesn’t actually have the power to offer asylum herself, however. She said in the interview that such a decision would be up to the French president, prime minister and foreign minister. And Taubira just last week threatened to quit her job unless French President François Hollande implemented her juvenile justice reforms.

So, basically, "not going to happen".

Comment Re:The Moon is the way to go (Score 1) 169

Why would you build a moonbase for a radiotelescope or gravity wave detector? What's the argument for dropping it into a gravity well (where it can be exposed to moonquakes and moon dust) and having people operate it when you can just have it unmanned and in space (Earth-Moon L2 for a radiotelescope, Earth-Sun L5 for a gravity wave detector) at orders of magnitude less cost and far greater effectiveness?

Every one of these sort of proposals just screams "I'm an excuse that was made up solely to give us a reason to go back to the moon". The most glaring is surely 3He mining, of course ;)

Comment Re:Part of why I didn't become an astronaut (Score 1) 169

We see the propulsion breakthroughs right now - there's a wide range of propulsion systems possible with current technology. Unfortunately, the turnaround on these sort of things is measured in decades (generally with a number well over "1"). And if it has any form of the word "nuclear" in the title, multiply the average time from conception to deployment by a large number.

Comment Re:dirt cheap rocket launches (Score 1) 169

Nobody of course is requiring rockets to be our long-term future. I have a soft spot for the Loftstrom loop concept, for example (aka, a track that holds itself up via the centrifugal force of a rapidly spinning rotor magnetically suspended in a vacuum inside it). Way more efficient and high throughput than a space elevator and requiring no unobtanium.

Comment Re:dirt cheap rocket launches (Score 1) 169

It would of course not make fuel cheap until we can learn to mine cheaply in space. And we're not even 1% to that stage. You have to pretty much relearn how to do everything you take for granted on Earth in space. Look at Philae just attempting to softly touch down at very low speeds - it had four different ways to try to stop it from bouncing (shock absorbers, ice screws, harpoon, counter-force rocket), and it still bounced way off and ended up in some rocks somewhere. And you're picturing setting up a whole refinery there? Yes, some day. But that day is not close.

The radiation issue is a big one that a lot of people downplay (they forget that the only reason the Apollo astronauts got away with as little shielding as they did was that their missions were on the order of a week or so long - and even still, they would have been in bad shape if a solar storm had hit. As it was they reported seeing regular flashes of light from cosmic rays impacting their retinas.

There've been a number of proposals for how to deal with shielding. One is to build a mini-magnetosphere around the spacecraft; my last reading on the subject was that it would be a realistic way to deflect most solar radiation but not GCR. You still really need physical shielding (which is a complex topic... beta and gamma are blocked by heavy metals far better than they are by light materials, but neutrons need to be moderated down to be stopped effectively, which means light, high scattering cross section elements like hydrogen; heavy ions tend to multiply high energy neutrons. And to make matters worse, forms of radiation switch around - betas kick off gammas due to bremmstrahlung, gammas can kick off photoneutrons or betas, betas can kick off neutrons too, neutron capture kicks off gammas, transmuted elements decay releasing gamma, beta, positrons, alphas, sometimes neutrons... It's really tough.

Most proposals call for using fuel, water, oxygen, etc as part (but not all) of the shielding - it's particularly good against neutrons, as all of these things are generally composed of CHON, all of which are good moderators (especially the hydrogen). A common proposal is to have the heaviest shielding around the beds, as you get better bang for your kilogram that way. I've pondered a more advanced version of that, having significantly more fuel / water / etc tankage space than you need (the extra mass would be part of your shielding anyway, so it's not really a "penalty") and having a computer system intelligently pump it around to where people are at any given point in time and where the sun is / what the current solar radiation flux is / etc. I wouldn't be surprised if you could cut the radiation dose to less than half in that manner, possibly a lot less. You'd need durable, reliable pumps, of course.

Comment Re:Little does we know... (Score 3, Interesting) 169

Are you kidding? I can't help but picture the MST3K characters ribbing it the whole time.

The main character is a "scientist" who doesn't use a single scientific term, instead using 50s pop-sci-fi style terms like "Oxygenator". I mean, here we have a botanist on Mars who doesn't even know the word "regolith" or understand why you'd have solar panels tilted at a particular angle. But don't worry, the book is full of such award-winning prose as phrases like "My asshole is doing as much to keep me alive as my brain". Seriously, it reads like a 13 year old boy.

But that's minor compared to how on pretty much every page we have Weir demonstrating his complete lack of knowledge of even the most basic aspects of every field of science he covers. Here, let's just pull up a random one:

Not because of the perfect landing, but because he left so much fuel behind. Hundreds of liters of unused Hydrazine. Each molecule of Hydrazine has four hydrogen atoms in it. So each liter of Hydrazine has enough hydrogen for *two* liters of water

High school chemistry, anyone? (Morbo Voice) Stoichiometry Does Not Work That Way! Weir again and again mixes up volume, mass, and moles. (For anyone not seeing it yet: hydrazine is 1,021g/cm^3, hydrogen makes up 12,5% of the mass, or 0,128 g/cm^3; water under STP conditions is 1 g/cm^3 and hydrogen makes up 11% of its mass, or 0,11 g/cm^3. 1 liter of hydrazine gives you 1,16 liters of water under STP conditions, not 2).

Here, let's grab another one of these from just a couple pages earlier:

"Once I get that hooked up to the Hab's power, it'll give me half a liter of liquid CO2 per hour, indefinitely. After 5 days it'll have made 125L of CO2, which will make 125L of O2 after I feed it through the Oxygenator."

Brilliant - not only do we have him once again confusing volume and moles, but we also have "liquid CO2", meaning that for some reason on a planet where a mere shiny bucket will hold frozen CO2 indefinitely, they've decided for no apparent reason to store it as a superfluid in heavy pressurized tanks at dozens to hundreds of atmospheres and elevated temperatures.

Oh, here's a great one: at one point he starts a diary entry by noting that he's now hiding out in a rover because he screwed up and didn't notice that his hydrogen levels in his habitat were climbing and his oxygen levels were dropping over the course of many days until he checked a meter. How much? The hydrogen went up to 64% and the oxygen levels to 9%. Really, the high squeaky voice didn't clue you in? The anoxic unconsciousness didn't clue you in? *Facepalm* Did this guy not get *anyone* to proofread?

The most mind-bogglingly glaringly bad stuff is of course the plants. As we all know, the sun is an incredibly energetic source. Look at the light in your living room for a few seconds. Notice how you're not blind. Now try it with the sun. Yeah, there's a bit of a difference. WIth the sun high overhead on a clear day the ground on Earth receives about 1000 W/m^2 of light energy. Now picture the brightest CFL you can find on the market - maybe one of those giant 40-watters? To match the light output of the noon sun would take 150 to 200 of them per square meter. Even taking into account angles, night, clouds, etc, it's a ton of energy. To grow the couple hundred meters of potatoes to feed a person? Well, you do the math.

So how does our hero plan to grow his plants? Here's Wier's entire justification

Also, the internal lights will provide plenty of 'sunlight''.

That's it. That's his entire justification on how he plans to provide enough light for his potatoes - normal interior lighting powered by a little solar farm on a dusty planet that receives half the light of Earth. Not even normal yields of potatoes, but super yields of potatoes! In regolith that he does nothing to remove the perchlorates or salts from (never mind that he does nothing to shield his electronics in his 100% ventilation-free canister from the humidity which he describes as raining down). And with Weir's humorously bad misunderstanding understanding of gardening we get his interpretation of potato mounding (aka, packing up soil around potatoes once they get to a large enough size to keep them focused on storing starch rather than going to flower):

Also, as their flowering bodies breach the surface, I can replant them deeper, then plant younger plants above them.

You see, the entire part of the potato plant that breaches the surface is merely a "flowering body". You can reuse space just by planting plants successively on top of each other like cordwood! Trust me, I'm a botanist!

Seriously, this thing is MST3K in book form. Hopefully the movie won't be this terrible. Or maybe it'd be best if it was...

Comment So long as you are ok with the other half (Score 1) 242

That the government, to avoid that, can use force to reduce the numbers. Specifically forcing industry and citizens to produce less CO2. Things like checks to see how much you drive and prison if you go over, forced shutdown of industry, etc.

If you aren't ok with that, then you can't very well say the government should be arrested. After all, they themselves don't produce all the CO2, society at large does. They can't magic it away, meaning the only thing they can do is force citizens to comply.

Comment Re:Movie? (Score 1) 41

Which is why you combine the chroma data from MVIC with the luminance data from LORRI. When you don't have both of the same image then you turn the chroma data into a sphere map and generate the appropriate chroma data to map over your luminance data.

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