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Comment Re:Efficiency. (Score 1) 937

You can actually get a very good measure of how your engines would do in a lighter vehicle by comparing recent Mustangs and F150s. The 5.0L Coyote engine is available in both and gets significantly different highway mileage and slightly different city mileage. The F150 is the less efficient in both cases. There is some slightly different tuning to take into account and I don't know how much of the difference should be attributed to that.

Comment Re:Efficiency. (Score 1) 937

I believe it is. My wife's car is a family 4 door that supposedly gets good fuel efficiency at 55mph. The extreme drop off in efficiency causes the non-performance cars to rapidly drop below the performance cars in MPG as you increase MPH, which is essentially what Top Gear demonstrated.

Comment Re:Efficiency. (Score 1) 937

In this instance, I'm pretty confident they were accurate. My own personal experience having gotten my first driving license on european hatchbacks and over the years upgrading through typical family 4 doors and on to more powerful performance cars, I found that hatchbacks/family 4 doors do great around the city, but once you're up to motorway speeds (70+mph), the extra high gears combined with the higher HP in the performance cars tend to produce better fuel efficiency. The drop off in efficiency for non-performance cars once you go over about 55mph is really extreme. I spent a long drive in my wife's car playing with her cruise control. Her car has real time MPG reporting. The drop off in efficiency between 55mph and 65mph was like a cliff. The drop off in efficiency for performance cars appears, in my experience at least, to be less extreme.

Comment Re:Efficiency. (Score 3, Informative) 937

Top gear did a good episode demonstrating fuel efficiency where they put something like a Ford Focus (some small "economical" hatchback) up against a BMW M3 on their track. The requirement was the Focus had to race the track, the M3 just had to keep pace, whoever drove the greater distance on a single gallon of fuel won. The M3 thrashed the Focus.

The Focus at 75mph (typical motorway speed in the UK) is running at a much higher RPM (probably 4000+RPM, I can't say for sure but my old Peugeot 306 ran about that) than the M3, which is practically idling at that speed. It's part gearing, if you gave those hatchbacks an extra top gear they could get great efficiency at real motorway speeds. It's also horsepower. If you generate more HP per revolution, you don't need so many revolutions to maintain a speed. Obviously there's a balance as increasing HP typically means decreasing MPG.

Comment Handel-C (Score 1) 365

I don't know how easy it would be to port your specific algorithm, but I did my masters thesis around a language called Handel-C. It's a super-set of C that provides a high level FPGA programming interface. That might get you some distance in determining the number of gates. Disclaimer: I was working with it a few years back and the documentation/support was appalling, I don't know if it's become any better.

Comment Re:What's that smell? (Score 1) 103

I went to college with the the guy. He has been working on this for coming up on 4 years now. The games I've seen so far are simple platformers reminiscent of the first Mario games, but everything has to start somewhere. That 3D Ludum Dare entry is a step up. It's all very legitimate, but I don't see it generating an RPG any time soon. Simple Mario/Doom clones though are bread and butter.

Comment Re:I wish I could say "none" (Score 2) 312

There is always enough space to maintain a braking distance, the traffic may just have to travel a little slower. The only issue I've seen with it is drivers cutting each other off because they don't understand braking distances or how to safely maneuver between lanes. I manage to maintain safe braking distances, I probably just average 5 mph slower than the traffic around me, which in reality is the result of matching speed with the car in front of me, then having to slow down when somebody gets between us to again increase the space to a safe distance. Doing that has saved me from an accident on exactly 2 occasions since I moved to the US; both times the traffic in my lane only (supposedly the "fast" leftmost lane), stopped very abruptly, then moved off again with no apparent indications as to what had caused the stop in the first place. On one of those occasions, had I not left an appropriate braking distance, I would certainly have hit the car in front of me as I was tired and reacted slowly.

Comment Re:I wish I could say "none" (Score 5, Interesting) 312

I moved to California from the UK a few years back and frankly, the CA driving test is a joke compared to the UK test. I didn't have to do any reversing, I was not tested on any maneuvers (3 point turn, parallel parking, etc...), and I passed the written component having only done the sample tests on the dmv website. For the UK theory test (identical in style to the written component of the CA test, but done on a computer) you have to know things like average braking distances for a typical car at 10mph speed increments from 20mph to 70mph. Might see a bit less tailgating and fewer multi-car pileups if CA drivers knew those numbers.

Comment Some good Sci-fi/Fantasy (Score 1) 796

  • Good Omens - Terry Pratchett and Neil Gaiman. A comedy about the coming of the anti-christ. Very British humour.
  • Nine Tomorrows - A collection of shorts by Asimov. Some very interesting visions of the future that have been the basis for a number of more recent authors' work.
  • Snow Crash - Neal Stephenson. The backdrop is an interesting vision of a hyper-privatised world.
  • Foundation - Asimov, the whole trilogy. At a deep level, it observes the cycles of civilization and the optimal methods of control exerted at different stages of development.
  • The Marching Morons - Cyril Kornbluth. Sometimes I feel this is where the world is headed.

Intel CPUs are not defective, they just act that way. -- Henry Spencer