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Comment Re:TI calculators are not outdated, just overprice (Score 4, Interesting) 359

Or if a competitor made such a hypothetical $25 replacement for the TI-84/86, schools could just standardize on the new model. The argument for not switching to Casio, etc. right now is that younger siblings typically get their older siblings hand-me-downs, but if the replacement model was only $25, that argument would loose a lot of weight.

Although with the Ti's current tenure, they're now getting into the range where there's likely students using their grandfather's hand-me-down calculator in class. I know students were using their parent's hand-me-down Ti calculators when I was in school.... and I'm old enough now to have kids of my own in school

Comment Automotive analogy (Score 2) 253

Because everything needs an automotive analogy.... "Car dealers should keep one of every part in stock for every car that's currently under warranty"

This would be completely unrealistic for a car dealership to do, so instead they stock only the parts used most frequently, and then just rely on the manufacturer to have an appropriate stock at regional/national warehouses. It's been this way for years, and yes it's an inconvenience for the day or two (or ten) that it takes the parts to come in, but it is what it is.

Perhaps the better plan, again taking a lesson from dealerships, would be to have "loaner" phones on hand to let you borrow while you wait for a "new" phone to come in. Of course, dealers seem to never have enough loaner cars, and I'm sure the phones would be the same thing - they'd also need to address the concern of getting the phones back (perhaps have warranty phones shipped to local store, and only given out upon receipt of the loaner?).

Comment Re: The "news for nerds" on this.... (Score 1) 961

I'll admit to having no technical reference for this - just a decade of driving and tuning race cars and reading all I can on the matter. I'd argue we're both correct - at the micro level you're absolutely correct - a more compliant suspension will both give more grip and more driver confidence.
However at the macro level a stiffer suspension will give less body roll, leading to better camber control, and thus more grip.

Comment The "news for nerds" on this.... (Score 5, Informative) 961

Since Slashdot is supposed to be a place for nerds... and nerds like to know the technical details more than just sensationalizing the latest headlines (or at least like to think so).... here's some technical information on why cars like the Porsche Carrera GT is so difficult to drive. I unfortunately don't have time to write out all the details here, but here are some basic principles of automotive suspension tuning to keep in mind:

  • There's nothing special about it being a "Porsche" in this scenerio. It's more a factor of being an aggressively tuned high-performance sportscar. Your Toyota Camry will have a VERY different handling profile than the ones you see circling at the Daytona 500 - despite both being "Toyotas". To lump the precieved "dangerous" handling of a Porsche 930 (the car that started the sensationalizing of being a "dentist killer") with a Carrera GT, just because they're both "Porsches", is almost equally absurd.
  • There's nothing unique about the Porsche Carrera GT that could cause these crashes - other than perhaps that they're headlines when they happen. It's more a factor of it being an agressively tuned chassis than anything unique to "Porsches". Most of the top-level modified "race cars" you'll see at any amateur racing event will have much the same "issues" of being hard to drive.
  • Pneumatic tires require a "slip angle" to work properly. This is defined as the angle between where the tire is pointing, and where the car is heading. Even when you're driving your Prius at 20mph around a casual bend, there will be some flex between the angle of the tire and the angle of the car (this is why your Prius tires don't last forever) - it's a very, very small angle in that case, but it critically exists.
  • In any suspension design, you'll have something resembling a basic bell curve that describes the ratio between slip angles and the amount of grip available. As you increase slip angle, you'll have more grip in your Prius... to a point, at which it will start to fall off
  • The more aggressively you tune a suspension (stiffer components, stickier tires, etc), the higher the peak of this bell curve will be.... but at the same time the steeper the drop offs on either side of that peak will be as well. This bell curve is how drifting works, and why drifting isn't the fastest way around a corner. At very high slip angles you'll have much the same grip level as at very low slip angles - meaning that your cornering speeds at large yaw angles will be very similar to our casual Prius driver.
  • Aggressive race cars will want the absolute highest peak possible, even if that means sacrificing the area under the curve. Drift cars conversely will look for maximum area under the curve, as it will allow them a larger window to play in. Street cars will be tuned for a very flat curve, as it's the most natural to the average person - they'll also need to compromise total area under the curve in the quest for comfort.
  • The stiffer components in a suspension will improve the suspension's consistency (input x = output y) and responsiveness. This increased responsiveness will also make things happen quicker (duh), so you had better have a quicker reaction time if you hope to "catch" any mistakes. In high-strung race cars (open wheel formula cars for instance), this responsiveness can become so quick that you almost have to predict the mistakes as you can't move your hands quick enough to "catch" them if you wait for them to happen before trying to adjust. Likewise, your "catches" need to be more precise, as you've got a smaller peak in that bell curve above to aim for.

As you can see... the more aggressive you tune a chassis (which the Carrera GT was designed to be very aggressive, as that's the market they were after), the less compliant the car will be, and the more apt it will bite you if you make a mistake. Is this unsafe, or just a fact of the physics involved that you can't drive an aggressive sports car and expect it to handle like your Camry?

Comment Re:No, it isn't (Score 4, Informative) 961

Lift off oversteer isn't exclusive to Porsche - pretty much any car that adheres to the laws of physics will do it. It stems from the weight transfer off the rear wheels when you lift off the throttle (due to less forward acceleration pushing the body of the car "back"), this decreases the normal force on the rear tires, causing the total grip to decrease in the rear (while the exact opposite is happening at the front end), and shifts the grip balance towards the front.

The only reason most "other" cars don't exhibit this behavior as strongly is that they aren't setup (from the factory) with such a neutral balance - they're setup to understeer so strongly that the balance window you play in goes from "more understeer" to "less understeer" - not "understeer" to "oversteer".

Comment Re:Cheating and/or paying through the nose (Score 1) 717

They've already done this...

Many "crossovers" (which are just hatchback sedans with lift kits) are being classified as "light trucks" to both improve their passenger car average (by removing the less efficient vehicles from that spectrum), and improve their light truck average (as they are "ringers" in the truck mpg category). Additionally, cars have been getting slightly longer and wider on average, as increasing this footprint gives them the same gov't break as actually increasing the fuel economy, but is much easier to do.

A classic example of this is the PT Cruiser (which is just a 4 door Neon hatchback with some "retro" styling cues) is being classified as a light truck.

Comment Re:Motion sickness (Score 2) 41

If you do get motion sickness (which is entire possible), it's also very likely to go away pretty soon. I get exactly the same feeling you describe anytime I get new glasses or contacts, but within an hour it's barely noticeable and by the next day you don't even realize it anymore.
As a regular contact lens user, I would appreciate some contacts that give you a wider field of view even just for daily wear

Comment Trust me... (Score 2) 238

"I'm an interenet expert, and I've seen what damage it can do... you don't want it"

Possible that he just self-proclaimed himself as an "internet expert" to add credibility to his claim that DPRK doesn't need or want to be on the internet? Also would add to his magical mystique - "All praise our dear leader for being so skilled on the internet to save us from it".

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