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AI Expert: AI Won't Exterminate Us -- It Will Empower Us

Smidge204 Re:AI is not just a look-up program. (414 comments)

2. See that guy in the cubicle next to yours? Prove that he is "self-aware".

The guy in the cubicle next to mine spends his lunch hour browsing Fox News, Drudge Report and Townhall. I can make a very solid case that he's not.
=Smidge=

about a week ago
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Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

Smidge204 Re:Efficiency??? (103 comments)

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=

about two weeks ago
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Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

Smidge204 Re:Efficiency??? (103 comments)

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=

about two weeks ago
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Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

Smidge204 Re:Efficiency??? (103 comments)

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=

about two weeks ago
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Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

Smidge204 Re:Efficiency??? (103 comments)

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=

about two weeks ago
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Elite: Dangerous Dumps Offline Single-Player

Smidge204 Re:Even Donations Come with Obligations (473 comments)

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=

about a month ago
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Elite: Dangerous Dumps Offline Single-Player

Smidge204 Re:Buyer Beware (473 comments)

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=

about a month ago
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MARS, Inc: We Are Running Out of Chocolate

Smidge204 Re:The Fix: Buy good Chocolate! (323 comments)

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=

about a month ago
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Fusion and Fission/LFTR: Let's Do Both, Smartly

Smidge204 Re:Fission is Dead (218 comments)

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=

about 2 months ago
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Fusion and Fission/LFTR: Let's Do Both, Smartly

Smidge204 Re:Fission is Dead (218 comments)

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=

about 2 months ago
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Fusion Reactor Concept Could Be Cheaper Than Coal

Smidge204 Re:What? (315 comments)

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=

about 2 months ago
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Fusion Reactor Concept Could Be Cheaper Than Coal

Smidge204 Re:What? (315 comments)

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=

about 2 months ago
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Fusion Reactor Concept Could Be Cheaper Than Coal

Smidge204 Re:Wait... (315 comments)

He means without having to have a reaction mass the size of a star ...

'Ivy Mike' was only 54 tons - considerably less than the mass of a star.
=Smidge=

about 2 months ago
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Fusion Reactor Concept Could Be Cheaper Than Coal

Smidge204 Re:What? (315 comments)

Or... maybe we don't have fusion reactors because nobody has really made one work on any scale with any real power.

That takes money.

Raising money almost always requires some promise of payback.

Since working, sustained, energy-positive fusion has never been demonstrated, there is little promise of payback.

Chicken vs. Egg. You're going to have a tough time raising sufficient funding to build a working demonstration if a working demonstration is a prerequisite for raising money.
=Smidge=

about 2 months ago
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Living On a Carbon Budget: The End of Recreation As We Know It?

Smidge204 Re:Good luck with that. (652 comments)

Homes made in the 30s though the 50s all fall under the "30+ years" critera. It's also not so much how well they were built at the time, but how well they've held up. In either case, there are absolutely improvements that can be made without going too crazy.

Old single-glaze aluminum frame windows replaced with double glaze vinyl. Old, settled insulation in exterior walls and attics replaced or augmented with new. Using a gas furnace for a hot-air system? Replace it with a condensing furnace will bump the efficiency from ~78% to ~95% and you'll make that investment back in savings in just a few years... should be able to get one purchased and installed for ~$2k. (There's probably government incentives to help pay for it, too.) LED lighting can easily take a chunk out of your electrical bill.

If one does feel inclined to go crazy, then PV on the roof is the first and obvious choice with a payback typically 5 years or less. Heat pumps for domestic hot water and home heating and replacing gas-fired with electric appliances... savings are multiplied with PV since you're not paying much extra for the electricity. Radiant floor heating (hydronic or electric) to replace forced air or baseboard hydronic systems. Heat or energy recovery ventilation. Passive heating/cooling. Sky's the limit, really!
=Smidge=

about 2 months ago
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Living On a Carbon Budget: The End of Recreation As We Know It?

Smidge204 Re:Good luck with that. (652 comments)

Better insulation to curb heat loss?

Better construction standards to reduce or eliminate infiltration of unconditioned air?

More efficient heating appliances? (Anything over ~10 years old can absolutely be upgraded)

More efficient heating/cooling strategies? (e.g. zoning)

There's absolutely more that can be done with a typical suburban home to reduce energy use. A 60% reduction on an older (30+ year old) home could actually be pretty easy if it hasn't already been renovated.
=Smidge=

about 2 months ago
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Living On a Carbon Budget: The End of Recreation As We Know It?

Smidge204 Re:Good luck with that. (652 comments)

A typical american could use 1/3rd or down to 1/4th of the energy he uses and the whole country could cut down to 1/10th and no one would realize any difference.

This, I think, is the most important thing to keep in mind; When discussing "quality of life" in terms of energy, we can reframe it of in terms of energy*efficiency. We can lower energy use without reducing QoL by improving efficiency.

Not impressed? Was not meant to impress you. That is per year not per month.

I'd be more impressed if that was per month... it would be nearly three times as much energy as my entire house uses, which is roughly four times the size of your apartment. And I have all electric appliances!

Anyway, at some point in time your energy will be green, and your energy demand will drop and then you have to fight the power companies about: why can it be that my electricity is so expensive when YOU get it for 'free'?

An argument easily won: I'm charging you for "free" green power because it costs me money to build and maintain the infrastructure that harnesses and delivers it to you.

It's kind of like asking why gasoline is so expensive when the oil is available for free, just sitting under the ground.
=Smidge=

about 2 months ago
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Energy Utilities Trying To Stifle Growth of Solar Power

Smidge204 Re:So? (488 comments)

Our government has backed an expensive and inefficient renewable energy tech - that's the only reason we're even having this conversation.

As opposed to our government backing an even more expensive and inefficient incumbent system?

By subsidizing solar power for domestic installations, that tax money is effectively being put back into the hands of the general public through savings, rather than into the coffers of multi-million dollar, often international corporations where it can further corrupt the system.

And I'd be happy to pay a "road use tax" even though I don't drive an EV (yet...). I figure I pay about $130/yr in gasoline tax, which if I switched to an EV I'd save about four or five times that easily.
=Smidge=

about 3 months ago
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Scientists Seen As Competent But Not Trusted By Americans

Smidge204 Re:Americans trust science too much (460 comments)

If you can cite a study to prove your point you have won the argument.

That's not trusting science too much, that's laziness. Usually the person citing the study has a tenuous grasp of what it really says, and in all but a handful of cases they are betting on the fact that few people will bother to look it up and read it themselves.

You can tell this is what's going on, because it only further polarizes people; if the "study" reinforces their existing view, then it's the best thing ever, and if not then the scientists who did it are clearly corrupt or they're just plain wrong. No attempt to understand, nothing changes, just reinforcement of bias.
=Smidge=

about 3 months ago

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More info from Nissan LEAF Tour

Smidge204 Smidge204 writes  |  more than 4 years ago

Nissan's national tour of their new electric vehicle offering, the LEAF, recently completed its last stop at the Liberty Science Center in Jersey City, New Jersey. Nissan representatives were on hand answering questions about the car and their plans to bring it to market, and I was able to collect a lot of good information which the Slashdot community might find interesting and useful. Below is a fact-dense summary of everything I was able to tease out of them.

The LEAF is a 5 passenger, 4-door hatchback bearing a striking resemblance to the currently available Versa, although once you see it in person it becomes obvious that the car is an entirely new platform designed specifically as an electric car, rather than a tweak of an existing vehicle. First impressions, shared by other visitors I met, was the vehicle was much bigger than the phrase "electric car" brings to mind.

The LEAF's technical specifications are no less impressive, though still somewhat tentative as production is not scheduled to begin until this fall:

80kW (107.3 HP) synchronous AC motor producing 380 ft-lbs (280Nm) torque. 24kWh worth of air-cooled, modular (48 modules, 192 cells total), laminated lithium-magnesium batteries located under the floor and rear seats giving a listed driving range of 100 miles (as tested under LA4 methods, aka "the city test") and a max speed of over 90MPH (144KPH). Curb weight is approximately 3300 pounds (1500 kg) including the 480 pound (217 kg) main battery pack. The main battery is rated for full capacity from -30ÂF to +100ÂF (-34ÂC to +38ÂC) and has a life expectancy of 7 to 10 years, with "end of life" defined as capacity degraded to 70% of the original. The LEAF comes with four wheel disc brakes and two stage regenerative braking which can recover up to 30% of the vehicle's kinetic energy in most situations. Brakes are hydraulic (w/ electric booster) and steering is drive-by-wire. A cable operated parking brake is also included.

Power from the main battery is cut in the event of an accident for safety. It is not known if a separate kill switch for disconnecting the battery manually will be provided.

The LEAF is capable of three charging options: it comes standard with a 110v outlet charging cord, allowing you to plug your car into any 15 amp outlet for charging via the charger incorporated into the vehicle itself. Charge time for 0% to 100% is estimated at 16 hours using 110v. Alternatively, you can charge the car using 208v using a required "charging station" in about 8 hours from 0% to 100%. Both of these methods use the same J1772 socket, recently made a standard by SAE International, meaning this and all other vehicles that plug in to charge will use the same connectors.

The 208v "charging station" is, I was told, simply a surge protector and over-current protection device which must be professionally installed and certified for code compliance and liability issues. While Nissan plans to offer Nissan-brand charging stations, you will not be obligated to buy one as the 110v charging cord is supplied with the car. Charging stations may also become available from third party manufacturers since they do not contain anything proprietary, and like the J1772 connector should be compatible with any plug-in car on the market.

The third "quick charge" option uses 480v connection through a second, dedicated socket and connector and can charge a dead battery to 80% in just under 30 minutes. Quick charging is halted at 80% to prevent damage to the battery. There are no plans to offer quick charging stations to the general public since very few houses have 480v electric service available. Nissan is working with private companies to install both 208v and 480v public charging stations for general use.

The LEAF includes, as standard equipment, an integrated GPS navigation system which helps you plan routes that pass near by public charging stations. Monthly updates to the navigation system will be provided for free. Also included is 3G communications which allow the on-board computer to send and receive data via the internet. The computer can be configured to send e-mail status updates, and various features such as charging schedules and heat/air conditioning operation can be done remotely via internet connected PC or cell phone. When asked about privacy concerns, the reps said that Nissan plans to collect usage data via an opt-in program only from their initial test users. There are no long-term plans to monitor driving and charging habits.

Other standard features include heated seats and steering wheel, air conditioning, power locks and windows, AM-FM/CD stereo with aux input for portable players, keyless entry/startup and 24/7 roadside assistance. All vehicle lights are LED. Features that are not offered include power seats, sun roof and spare tire.

The "ignition" is a large power button located just below and to the right of the steering column. The rep said there is no delay turning off - meaning you don't have to hold the button - but she never tried it "at speed" so it is unclear exactly what will happen if you turn the vehicle off while driving.

There is no set price yet, but I was given a target range of $28,000 to $33,000 before rebates and incentives. Official pricing is due to be announced in April. At present, the LEAF qualifies for $7,500 in federal tax rebates, along with 50% of the install cost for the 208v charging station (up to $4,000). Additional rebates and incentives may be available from your state government as well. Nissan plans to offer buy and lease options, but they can not offer battery-only leases due to federal laws. The federal government considers the battery to be part of the drive train, and it is illegal to sell a car without a functioning drive train.

Production is scheduled to start in Japan this fall, with a portion of those vehicles being imported to the US for test markets and early adopters. Official announcements are scheduled for December of this year. By 2012 Nissan plans to have a vehicle and battery manufacturing plant operating in Tennessee with a capacity of 150,000 vehicles and 200,000 battery packs per year.

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