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Comment: Re:Scare them with China, make it a contest again (Score 1) 287

by dabridgham (#48744443) Attached to: Should We Be Content With Our Paltry Space Program?

Mostly I'm a fan of orbital colonies but lunar bases do have some advantages. Gravity is helpful for a lot of things but the moon doesn't have so much gravity that it's terribly difficult getting out of it. So basically the moon would make a good launch platform for access to the rest of the solar system. Manufacturing that can use gravity goes on the moon while the rest is done in free-fall. Leave the Earth as a bio-preserve; it's the only one we have so far.

Lunar farside is a great place to site optical and radio telescopes. A nice stable platform to anchor to and shielded from the noise of Earth. Not so good for the infrared telescopes.

Also, the regolith is handy as a radiation shield.

Comment: Consensus is for Quakers (Score 0) 770

by dabridgham (#47853149) Attached to: How Scientific Consensus Has Gotten a Bad Reputation

Years ago, a friend told me that the word consensus should only be used by Quakers; they were the only ones who knew what it meant. I scoffed. No, it was far too useful a concept and not that difficult to understand. The global warming debate has changed my mind. Only Quakers may use the word consensus.

Comment: there are no cuts (Score 1) 277

by dabridgham (#42978087) Attached to: How Sequestration Will Affect Federal Research Agencies

The things is, as far as I can tell there are no actual cuts in spending. It's simply that they're going to get a 5% increase in spending instead of an 8% increase and they're calling that a 3% cut and claiming the sky will fall. It shouldn't surprise me that we fall for this but it does.

Comment: Re:Assault Rifles (Score 1) 1435

by dabridgham (#42460597) Attached to: Newspaper That Published Gun-Owners List Hires Armed Guards

It's probably pointless to repeat this since accuracy in language is likely lost, but I'll try anyway.

"Assault rifle" is a technical term and means a rifle that has select-fire. For instance, the M16 that you refer to.

"Assault weapon" is a legal term and while its exact definition varies some from jurisdiction to jurisdiction, it basically means a semi-automatic rifle that looks like an assault rifle.

So you can see that there is, in fact, no such thing as a semi-automatic assault rifle. If it's semi-automatic, it's not an assault rifle because it doesn't have select-fire. And if it's an assault rifle, it's not semi-automatic, it's full automatic.

Comment: Re:The critics can learn a thing or two about emac (Score 2) 127

by dabridgham (#40072329) Attached to: Emacsy: An Embeddable Toolkit of Emacs-like Functionality

You can hardly blame Emacs that programs which came years later chose different keyboard commands.

As for not being keyboard-centric rather than mouse-centric, some of us consider that a feature. Being created before mice has something to do with that of course but having to pull your hands off the keyboard to find the mouse is terribly slow. Yes, there's a bit of effort needed to learn enough to make running Emacs comfortable but when you're there you'll find how painful mice are. By the way, C-/ is only harder than C-z if your right hand is stuck over on the mouse.

And finally variable-width fonts. I sort-of agree with you there. They'd be useful for some thing.

Comment: Re:Answer, in brief: (Score 1) 556

by dabridgham (#38707304) Attached to: Can NASA Warm Cold Fusion?

I've never heard of that. As far as I know, the word means what it means from physics even if you're talking about energy sources. A 3kW generator can deliver 3kW for as long as its energy source holds out. In other words, saying it's a 3kW source really is not a complete description of the energy you can get out of it. You need to know how big the fuel tank is.

A 3kW hydro-generator can deliver 3kW for so long as the water keeps flowing. A 3kW diesel generator can produce 3kW of electrical power so long as the diesel tank is not empty (and it doesn't break). And a 3kW battery . . . Oops. That would be exactly the error we're all trying to explain to you. Battery capacity is measured in kW-hours or amp-hours (with the battery voltage implied to convert it to an energy unit). In other words, when you want to talk about energy capacity you need to switch to units of energy not units of power.

Comment: Re:Answer, in brief: (Score 1) 556

by dabridgham (#38707110) Attached to: Can NASA Warm Cold Fusion?

Interesting how you can get all this right and be completely wrong everywhere else.

Yes, 1 kWh is 1,000 J/s for 3,600 s. Notice if you multiply those together, including the units, the seconds in the numerator and denominator cancel and you end up with 3.6 million Joules. 1kWh = 3.6MJ.

Joules is a unit of energy just like kWh and unlike kW, which is a unit of power. Power is how fast energy is being used (consumed or generated).

Comment: Re:Answer, in brief: (Score 1) 556

by dabridgham (#38706400) Attached to: Can NASA Warm Cold Fusion?

Yes, I'd noticed the order of magnitude disparity in pricing between his large system and his small. I think he's claiming that since he'll mass produce the small units, they'll come out 10 times cheaper per kW than a large installation.

Hey, I didn't say I believed any of this. I just wanted to point out the common error of confusing kW (unit of power) with kW-hr (unit of energy). Saying that $150/kW is a lot more than the cents/kW-hr you buy electricity off the grid is a nonsensical comparison until you start taking in a lot of other factors, as you did in your post.

At the source of every error which is blamed on the computer you will find at least two human errors, including the error of blaming it on the computer.