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Comment: Re:Death traps. (Score 1) 451

by Alioth (#49291863) Attached to: Lyft CEO: Self-Driving Cars Aren't the Future

You are somewhat the rarity with your vintage car. For most people, drive by wire is already a thing. The throttle has been drive by wire for years on most cars, and some of today's cars are steer by wire. (Yes, there is manual reversion if it fails, but in normal driving you have no mechanical connection between the steering wheel and the wheels of the car). Many cars can brake independently of the driver. Even my 2007 Civic has traction control and ABS fitted as standard.

Comment: Re:Buggy whip makers said automobiles aren't... (Score 1) 451

by Alioth (#49291749) Attached to: Lyft CEO: Self-Driving Cars Aren't the Future

Traffic would probably flow considerably better in a city full of self driving cars. A lot of the chaos of city driving is because of human error and human reaction delays.

You only have to fly over a traffic jam on a major highway to see problems that could be significantly alleviated by self driving cars that communicate with each other. Quite often you see traffic jams with no explanation - a mile of stationary traffic, but there's no obstacle in front and none behind. What happened is two hours earlier someone slammed on their brakes, someone following too close had to brake harder, and eventually the whole highway stops. As long as traffic is not leaving the stopped area faster than it is arriving, you get a self-sustaining traffic jam long after the original cause has gone away. The self driving car will reduce the instances in the first place of the cause, and if it does happen will be able to as a group moderate their speed in such a way that you don't end up with a mile of stopped cars. Instead of the next car only starting after it has seen the previous one begin to move + reaction delay, all cars will be able to start moving at once or nearly so.

Comment: Re:Unicomp Keyboard (Score 2) 452

by Alioth (#49274333) Attached to: Ask Slashdot: Good Keyboard?

I have a Unicomp at home.

Our department is constantly criticised for "being lacksadasical", "not having enough urgency"... because our jobs involve sitting down and thinking a lot. (The finance director suggested we "walk quickly" to get rid of this perception).

My suggestion is we kit the entire department with Unicomp buckling spring keyboards. Not only will we enjoy typing more, but we will sound like an old fashioned typing pool, and we will sound hugely productive.

Comment: Re:I must have the math wrong somewhere... (Score 1) 328

by Alioth (#49249439) Attached to: New Crop of LED Filament Bulbs Look Almost Exactly Like Incandescents

I have dozens of LEDs and had so far only one failure in 4 years (I thought I had a new failure the other day, but there's a bad connection in the lighting circuit - the lamp works fine when put in another fixture), so "rarely last more than 4 years" seems unlikely at this stage.

The colour rendering is good enough, I replaced my kitchen lights with LEDs about 4 years ago and have not noticed any issues with colour rendering. A turn-on delay of 100ms is functionally instant (I can't imagine any case in my home where 100ms for a light to turn on will be significant - and tungsten bulbs will require at least this long to warm up and glow at full brightness), and they are full brightness immediately (unlike GU10 CFLs that take 4-5 minutes to warm up). The EM emissions are utterly trivial. At the frequencies the current regulation electronics works at, there is nothing on the internal circuit board that is long enough to act as anything remotely close to an efficient antenna, and none of the lights I have bought are "dodgy" - they have all been tested for conformance to EM emission standards. They do not interfere with any radio equipment I have.

Comment: Re:This is a bug not a feature (Score 1) 328

by Alioth (#49249015) Attached to: New Crop of LED Filament Bulbs Look Almost Exactly Like Incandescents

My bike light is a seriously bright LED headlight (and tail light). The headlight is as bright as a car's headlight, and I ride on quite a few unlit roads. Once I've been out of streetlights for a while in the very white pool of light the LED headlight gives me, whenever a car comes the other way, their lights look as orange as sodium lights. Normally I'd see the lights of oncoming cars as more or less white.

Comment: Re:I'll never give up incandescents. EVER. (Score 1) 328

by Alioth (#49248979) Attached to: New Crop of LED Filament Bulbs Look Almost Exactly Like Incandescents

The system as a whole is far from 100% efficient. Once you add transmission losses and generation losses, electric resistive heating will be probably below 25% for the system as a whole, as most of the heat will be getting made outside of the building that's being heated.

Gas heating would be far more efficient as a system, since the losses in shipping the gas to your house to burn will be less than shipping the gas to the power station, burning it there to make heat, turning that into electricity, transmitting the electricity, then turning what's left back to heat in the building.

Comment: Re:Slow Down (Score 1) 117

by Alioth (#49248903) Attached to: Huge Ocean Confirmed Underneath Solar System's Largest Moon

That's surface temperature. This ocean is deep under the surface.

So the follow-up question would be: if it's deep under the surface, how will sunlight get there?

The answer is that sunlight isn't what's needed, it's the right amount of energy that's needed. The energy can come from a lot of other places. Tidal forces for example can heat the interior of the moon, radioactive decay can heat the core of a moon etc. so there may be quite a bit of subsurface energy. For example, if you look at the bottom of the oceans on Earth where there is no sunlight, there are oases of life around volcanic vents on the ocean floor (which are spewing all kinds of useful chemicals into the environment). So while the surface might be cold and lifeless, it's possible that there are significant amounts of subsurface liquid water at a temperature that's compatible with life of some description.

Fools ignore complexity. Pragmatists suffer it. Some can avoid it. Geniuses remove it. -- Perlis's Programming Proverb #58, SIGPLAN Notices, Sept. 1982