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Comment: Re:Home of the brave? (Score 1) 586

by Smidge204 (#48624973) Attached to: Top Five Theaters Won't Show "The Interview" Sony Cancels Release

I will bet your chances of being killed in a mall go way up if there are specific threats against that mall.

No, it doesn't. The mall could have been attacked at any time with no announcement at all. The only difference is now you know somebody out there has an axe to grind.

Knowing the odds does not change the odds.

In fact, I'd argue that you might actually have a slightly LOWER chance of being killed or injured if the the intent to attack is announced. They could be bluffing. Increased security could ward off or apprehend the attackers. Law enforcement might be able to intervene and prevent the attack.

The most realistic outcome of this scenario? The mall would be closed and your appointment canceled... but assuming for the sake of argument that doesn't happen, you might as well go because your odds are certainly no worse than at any other time.
=Smidge=

Comment: Re:Efficiency??? (Score 1) 103

by Smidge204 (#48518851) Attached to: Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

150Nm is about what a typical small car engine might be capable of at peak, but torque at the wheels would typically be greater due to gear reductions. Not really relevant, though - the torque of the engine applied to the wheels is not applied to the lug nuts on the wheels as a torque, but applied to the lugs themselves as a shear.

Maybe imperial units will help?

15 Newton-meters is roughly 11 foot-pounds. Most people can comfortably apply that kind of torque with a normal wrench, and that's about twice what a strong person could do with a screwdriver.

Torque specifications for lug nuts are typically in the 80 to 120 foot-pound range, though practically nobody outside of a reputable auto shop will bother with that (and even most reputable shops will gloss over it...). Most people, including myself, either use an impact gun or step on the lug wrench, which results in slight over-tightening. Figure a 150-lb person standing on a 12" long wrench and that's 150 ft-lbs... slightly over but not too bad.

For gasoline car engines, torque (ft-lbs) seems to always be fairly close to horsepower... so 120 ft-lbs is about right for a 120hp engine, plus or minus. It boils down to the fact that most gasoline engines are designed to run at a certain RPM, which makes the math turn out that these two metrics are often within maybe 10% of each other.
=Smidge=

Comment: Re:Efficiency??? (Score 1) 103

by Smidge204 (#48516591) Attached to: Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

As the AC said, for a very limited torque; 15 Newton-Meters. For a sense of scale, the recommended torque on a lug nut for a car tire is typically around 8-10 times that.

It's also under cryogenic conditions, intended for space applications, which is a rather special case (ultra-reliable under extreme environments) where it makes makes more sense to use something exotic.

And having said that, the more I learn about it the less I'm impressed with it. Magnetic bearings are pretty old hat technologically speaking, and the harmonic drive aspect is only novel in that it uses magnetic repulsion to flex the spline cup rather than physical contact. Meh. Even their "through-wall transmission" thing is a glorified magnetic stirrer.
=Smidge=

Comment: Re:Efficiency??? (Score 1) 103

by Smidge204 (#48515899) Attached to: Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

Your argument basically boils down to "since electric motors can produce high torque, then permanent magnet couplings can also provide high torque"

My contention is you make it sound way, way simpler than it is. Also, you'll find that the really big motors are not the permanent magnet type exactly because producing a high-torque motor with permanent magnets is more difficult and expensive. It's an issue of flux density.

I'm sure you COULD design a permanent magnet coupling for any particular purpose, but that doesn't mean it makes sense to do so.
=Smidge=

Comment: Re:Efficiency??? (Score 1) 103

by Smidge204 (#48515465) Attached to: Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

If you couldn't move high forces with a transmission like this, then you also couldn't generate them with an electric motor, because you couldn't hope for the magnetic fields to turn the stator against high loads.

Electric motors can stall, and when they do so they draw a terrifyingly huge amount of power compared to when they're operating properly. Providing that static torque is very expensive and often dangerous unless the motor and controls were designed for it.

It's not that magnetic fields can't be strong enough, it's getting fields that are strong enough without additional energy input.
=Smidge=

Comment: Re:Even Donations Come with Obligations (Score 2) 473

by Smidge204 (#48409445) Attached to: Elite: Dangerous Dumps Offline Single-Player

Sure, you could conceivably sue a charity but only if there is a blatant misuse of funds. Benefit of the doubt, most Kickstarter campaigns I feel do at least have honest intentions and use the money the collect in a manner consistent with those intentions... they just completely botch it. (Of course, there are some "genuine" frauds as well...)

Back on topic; How about offline play with an option to update at each launch? Seems like a good compromise; You don't *need* an internet connection to play, but you can still keep in synch with updates. "Always on" single player is complete bullshit, and I defy you to provide one example where a constant connection to the internet for single player has actually provided a benefit to game play that could not be achieved through a player-invoked update function.
=Smidge=

Comment: Re:Buyer Beware (Score 4, Insightful) 473

by Smidge204 (#48409055) Attached to: Elite: Dangerous Dumps Offline Single-Player

you just get a possibly sketchy promise of a "reward" for your investment.

Kickstarter is NOT an investment. An investment is when you put in a small amount of capital with the expectation that you will get some slightly larger amount of capital back after a period of time. You do not "own" anything when you give money to a Kickstarter project. You are not a stakeholder. You are not entitled to or owed anything.

Kickstarter is best described as a donation. Being more generous, Kickstarter is an advanced purchase, but since there is no guarantee to delivery it's not really that either.
=Smidge=

Comment: Re:The Fix: Buy good Chocolate! (Score 1) 323

by Smidge204 (#48397787) Attached to: MARS, Inc: We Are Running Out of Chocolate

Two things cross my mind;

One, it's amazing the things some people would rather have than money. People pay through the nose for tiny portions of animal products most people would consider dog food. I can totally see enough people buying chocolate at $0.40/gram or more (resulting in $15+ bars) regardless of ACTUAL quality. It's all branding.

Two, if there really does end up being a global cocoa shortage, you might not have much of a choice.
=Smidge=

Comment: Re:Fission is Dead (Score 1) 218

by Smidge204 (#48216981) Attached to: Fusion and Fission/LFTR: Let's Do Both, Smartly

Just to be absolutely clear, the dam was not built to generate electricity. That was just a nice side benefit.

Electricity was more than just a side benefit - it was a planned feature from the beginning.

And my original post was, of course, more than a bit tounge-in-cheek.

The point being that the storage of a large quantity of energy in the form of contained water, and the subsequent catastrophic release of that energy in the form of a structural failure, is absolutely a danger that needs to be considered but often is not, at least by the general public. However, the ACTUAL threats to public safety and environmental quality are greatly overstated for nuclear power - not to say they aren't real threats, but statistically speaking there are much more dangerous things out there. (Using Banqiao as the counterexample was the toung-in-cheek part in case you missed it.)
=Smidge=

Comment: Re:Fission is Dead (Score 5, Insightful) 218

by Smidge204 (#48171765) Attached to: Fusion and Fission/LFTR: Let's Do Both, Smartly

Safer than hydroelectric.

Including Chernobyl, there have been something like 56 direct fatalities, 4000+ deaths from cancer attributed to the radiation, and 350,000+ displaced peoples due to fission reactor failures. I'm not aware of any deaths *directly* attributed to Fukushima but let's round that off to an even 60.

Banqiao hydroelectric dam collapse: 26,000 drowned, 145,000 dead from disease and famine, 11+ million displaced.

Adjusted for GW capacity, hydroelectric power (970GW) is an order of magnitude more dangerous than nuclear (372GW).

Ban hydro power! ;)
=Smidge=

Comment: Re:What? (Score 1) 315

by Smidge204 (#48106899) Attached to: Fusion Reactor Concept Could Be Cheaper Than Coal

But the problem is that it's not just NG and peanuts, there's also soy, sunflower, corn oil, all sorts of things. And soy will always be cheaper than peanuts.

This is demonstrably false, otherwise any power plant ever built would use the cheapest and ONLY the cheapest source of fuel. Clearly that is not the case, is it?

You said it yourself: "And you don't use inferior tech if you have a choice." The problem is you might not fully appreciate what makes a particular technology "inferior" or "superior." Hydro electric power is by far the cheapest electricity there is, so by your reasoning every power plant would be a hydro plant... except that's not really the case. The reason why has to do with the more nuanced underpinnings of what makes a particular technology superior in a given situation.

To whit:

Got a lot of vacuum tubes that need replacement? None? Maybe because transistors are cheaper, more reliable, smaller and more powerful?

Vacuum tubes are still widely used in new equipment. For some applications their performance is unrivaled by silicon devices. And I don't mean audiophile bullshit either;

http://news.sciencemag.org/phy...

While lighter-than-air vehicles have largely (but not completely) been displaced for human and cargo transport, blimps and balloons are still used routinely because they are more practical and economical for certain situations. Balloons can reach altitudes that are extremely difficult for heavier-than-air craft and can do so for a fraction of the cost.

The only example you mention that has any merit is punchcards - but paper based scan sheets for data entry is still widely used because it's practical for some situations. The ubiquitous "scan-tron" exam answer sheet is an immediately recognizable example, and voting machines still use literal punch cards as a means to store information for later input into a computer. Even some electronic voting machines use scanned ballot sheets.

That's the problem when you speak in absolutes; it's very easy to prove them wrong.

And you have utterly failed to demonstrate that fusion power would necessarily be more expensive than any particular alternative, so even if the very premise of your argument worked in the real world, you still can't apply it to fusion.

Not there's only one: raising prices. Unless you are going to weasel-word your definition of "value", of course.

No weaseling here; you increase the value of a commodity by refining it into higher-valued commodities.

Let's use peanuts as your example. Not sure where you got $1/kg - probably another number you just made up - but they actually sell for about $420/ton. But why do they sell for even that much? Because they have a use! And if we increase the number of uses and/or the value of those uses, then the price will necessarily go up because of demand, barring government intervention/market manipulation.

Electricity is just like every other commodity. If you come up with new ways to use electricity that are otherwise superior to existing technologies, then the value of electricity is increased.

Value, of course, is not to be confused with price. They are related but not the same. Higher value can command a higher price, though...

Building a device that produces energy for higher prices does not lead to cheaper energy.

You haven't demonstrated that it would be at a higher price. Such a determination is impossible until we have a working technology, and even then it would be a tentative conclusion since future innovation might bring the cost down.

You're probably going to try to make a point about the billion-dollar price tag of ITER, but you'd be wrong for doing so because it's a research project and not a commercial endeavor. Thought I'd save you the trouble.

BTW, thanks for your post, I got a definite uptick in readers as soon as you posted it, Mr Streisand.

0 + 1 = 1. That's like an infinity-squared increase in viewership! But hey, at least you admitted to what's really important in this discussion.
=Smidge=

Comment: Re:What? (Score 1) 315

by Smidge204 (#48104593) Attached to: Fusion Reactor Concept Could Be Cheaper Than Coal

No design *ever* made can demonstrate that it can generate more *money* than it takes to run. This is important.

I assume you mean this statement only pertaining to fusion devices, and not in general... otherwise you deserve mockery. However, even if you did intend such a narrow application of that statement, you're still likely to be wrong as nearly everyone who made bald assertions about the limits of technology have been, given enough time.

The device does not need to have an economic value exceeding the value of the energy it produces, it just needs to be more advantageous than available alternatives within its lifespan. This argument is kind of absurd in its own right - there are lots of ways to make the energy it produces more valuable, and cheaper energy will actually tend to increase consumption as more applications become economically viable.

As for your sucky blog; I'll just point out one major nit to pick... there is no hard and fast rule that says you have to use tritium as a fuel. Most of what you wrote kind of hinges on tritium being a factor, and the ITER design in particular, and things start to fall apart once you explore other options.

I also like how you picked, seemingly arbitrarily, the highest dollar value for lithium ($4,500/t) you could find even from your own citation-less source article. You also completely gloss over the fact that if using lithium as a fuel source you'd need to use Lithium-6, which may or may not need to be enriched for natural Lithium.

But all that aside, best I can figure, one tonne of metallic lithium consumed in an ideal D-T fusion reaction will yield about 78 TWh. That's more than the daily consumption of *all* energy types in the US. $4,500 per day seems cheap when you put it that way.

There are a lot of very genuine technical reasons why fusion power might never come to be. It's a real shame you dropped out of your degree in physics or you could have stuck with those and had a blog post worth reading.
=Smidge=

C for yourself.

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