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Comment: Re:My experience driving a Prius (Score 1) 377

by habig (#47257361) Attached to: Are US Hybrid Sales Peaking Already?

If you're a highway warrior for the forseeable future your best bet is diesel. Electric power-trains truly show their strength in city driving due to the ability to regenerate from braking. On the highway the savings are too marginal.

I've been wondering how come there's not a diesel hybrid. Get the diesel goodness on the highway, the electric bonus in the city: make use of both strengths! Not like locomotives haven't been doing this for the last hundred years or anything...

Of course, I also wonder how come pneumatic hybrids aren't being developed more (I think Citroen is the only one out there). Storing energy as compressed air is more efficient than in batteries (which don't deal well with with high inrush currents), and don't have the "nasty chemical battery pack" issues.

Comment: Re:Submarines Move (Score 4, Interesting) 75

by habig (#46585137) Attached to: Physicists Produce Antineutrino Map of the World

When the Borexino experiment was being built (under the Appenines in Italy), they calculated that if a nuclear sub parked for more than a couple weeks in the same spot in the Adriatic, they'd be able to see it using neutrinos.

Not sure if anyone's redone that calculation now that the experiment works, but the preliminary one attracted some interest from the defense side of things.

There is a reasonably well thought out set of specs for "if DoD wants to use neutrino detectors to monitor nuke activity in, say North Korea, what would they have to build". Done from the perspective of the particle physics guys saying "if we can get DoD to spend some of its semi-infinite pile of cash on some neutrino detectors we're interested in, how would we do it?". The answer turns out to be almost feasible, actually. Here's only the most recent paper I bumped across, there are many others.

Comment: Re:Scientists "know"? (Score 2) 75

by habig (#46585009) Attached to: Physicists Produce Antineutrino Map of the World

Researchers don't "know" squat. They have lots of theories, none of which have supporting data. That's what makes the heat of the Earth's core a mystery. By all rights it should not be this hot. It should be dead cold like the moon.

How about "scientists have a pretty good idea". Here's a recent review article on geoneutrinos, which does compare direct neutrino observations and the overall heat budget.

Don't know everything, but the more tools you can turn on the problem, the more clear things become. Adds up to something a bit more than "squat".

Comment: Re:Pre-Science (Not To Be Confused With Prescience (Score 1) 580

by habig (#44257775) Attached to: Math and Science Popular With Students Until They Realize They're Hard

While this would result in graduates who really knew their stuff, I'm afraid the pressure is in the opposite direction. Administrators lean on faculty to increase the institution's "4-year graduation rate". Because legislators lean on them, because the public leans on the legislators. John Q. Public wants what he's paying for, a four year degree in four years, dammit! (despite the fact that an Engineering curriculum really is five years worth of stuff: it used to be here, and still is in much of the world). Given the current huge tuition rates, certainly that's understandable though: if penny wise and pound foolish.

Some people can learn what they need in less time than others. Some subjects are harder than others. But, everyone and every subject unfortunately has to be mashed into the same timeframe.

Of course, why it's ok for the "professional" careers (as if Engineer or Scientist isn't) you mention to require more schooling is a baffling exception. Good for those fields: they get the time to teach stuff thoroughly!

Comment: Re:why no dark matter black holes? (Score 4, Insightful) 44

by habig (#43774827) Attached to: Dark Matter, WIMPS, and NASA's Alpha Magnetic Spectrometer Data

If dark matter only reacts to gravity, why doesnt collapse into hgh density clumps over the eons? Ordinary matter is stopped from doing this by the electronmagnetic repulsion of atoms for masses less than a few hundred Jupiters and by hadronic stong force for less than couple Suns.

It does, we call those clumps "galaxies".

Note that the virtue of interacting only a little bit with normal stuff (via only the weak and gravitational forces, not gravity alone) actually makes it harder for dark matter to pack in tightly. Why? it's hard for a distribution of dark matter particles to shed kinetic energy and settle down more deeply into the gravitational potential well. Ordinary matter has all sorts of electromagnetic ways to shed energy and cool down.

If this thermal argument is opaque, imagine one WIMP, with some kinetic energy. It falls down towards the center of a galaxy. But, it seldom interacts to lose any energy, so zooms right back out the other side. Sort of a tiny, frictionless pendulum with a galaxy sized amplitude.

Comment: Go North, Young Man (Score 4, Interesting) 198

by habig (#43765499) Attached to: Data Center Managers Weary of Whittling Cooling Costs

Why don't they just site their centers up north? Here in Duluth, most of the year the outside air is cooled for free by mother nature. Heck, they could sell their waste heat to nearby homes and businesses and get a negative PUE.

Don't need to be green to worry about this, it's $$, something ever company wants.

Comment: Re:Everything Fedora is, RHEL becomes. (Score 2) 458

by habig (#42662551) Attached to: Fedora 18 Installer: Counterintuitive and Confusing?

So many poorly executed steps backwards... up2date replaced by yum

Heh - I always considered "up2date" to be the original awful college laptop pandering move, and rejoiced when yum got capable enough to replace it. yum+rpm does a pretty good job of package management. yum's scripted and configurable. up2date relied on users having a throbbing blinky thing on their desktop and taking action in a way which was spookily similar to Windows Update, plus it had a bad habit of taking all your memory and CPU in the process.

the abominable excrescence that is Network Manager on a wired machine...

On the other hand, I cannot agree with you more about this. Unfortunately, this happened long enough ago that Network Manager has since also infected RHEL and derivative server distros, which is even sillier. Step #1 on server installs for me is to rip it out by the roots, something which solves many problems (and should be the default install).

Comment: Re:I have the answer (Score 1) 589

by habig (#41443829) Attached to: Scientists Speak Out Against Wasting Helium In Balloons

Since the first two produce neutrons they will create considerably more low-level nuclear waste/J than a fission plant would, meaning they'll only be in use until we can manage aneutronic fusion instead.

I don't think it will be much of a problem. Fission waste is primarily the heavy daughters of the uranium: take that thing way up on the periodic table and split it semi-randomly in two parts, you get all sorts of stuff of varying nastyness. Now take that soup of middle-sized atoms and throw more neutrons at it, more problems.

However, if all you've got is a bunch of H and He isotopes in there fusing, tacking on more neutrons to them doesn't do much. Also, the neutrons released in these reactions don't have a whole lot of energy, so don't get very far. Much less of a problem.

Comment: Autonomous Gliders (Score 1) 35

by habig (#41171643) Attached to: Wave Glider Robot Helps Forecast Hurricane Isaac's Path

This is similar to the autonomous glider the people at the Large Lakes Observatory use to get data from something that's not moored in one place like research bouys are. The unit here in Duluth cruises around Lake Superior for a few weeks at a time, but they're standard equipment for oceanographers in bigger, saltier puddles too.

It uses the same means of propulsion: turning up-and-down motion into forward motion with wings. Its power source, however, is some onboard batteries rather than a solar cell limiting its endurance (but freeing it from dragging around the solar rig, so it can go deeper and faster). All the battery does is change the volume of a swim bladder, causing the glider to float or sink. Amazing efficient!

Comment: Re:Classy (Score 3, Insightful) 402

by habig (#40735811) Attached to: Jack Daniels Shows How To Write a Cease and Desist Letter

Why can't more companies act this way towards one another?

A cynical take on why lawyers don't usually act like this: the purpose of law and lawyers is to resolve conflicts. By doing so in a jerky way, they ensure more future conflicts, ergo, job security.

That said, these guys resolved this conflict in the best way possible, kudos to them: hope they don't get disbarred for it or anything!

The moon may be smaller than Earth, but it's further away.