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Comment Re:Science (Score 2) 63

Yes, more transceivers are better than less, thank you MIT.

But only if they're really tightly synchronized.

MIT got them to be tightly synchronized despite being in different boxes in different rooms, rather than all being in the same box, WITHOUT a lot of extra, extra-special, extra-fancy, extra-cost, hardware. This can be built with a bit more off the shelf stuff (maybe the SAME amount of the same off the shelf stuff but with a bit better firmware) and easily folded into the next generation's chips.

Comment Re:Not handy for the home (Score 1) 63

Since they are talking about many devices connecting to multiple routers it's not going to do much for the average home user then. I may have a couple of devices but only the one router.

  - If you got a second router, put it some distance away from the first, and hooked them together with a network cable, you could use two devices about as fast as you could one with one router.
  - If you had three wired routers you could use three devices close to as fast as you could use one with one router.
And so on.

Note that I'm not talking about using the devices with each near a particular router. I'm talking about the routers spread out around the room or the house and the devices also somewhat spread out - but differently (even just at different spots in the same room) and with no particular relation between the device and the router locations.

Comment Re:We're not in a mimimum yet. [Re:Of course. . .] (Score 1, Informative) 299

There is some possibility that the sun may, at some time in the future, enter another sunspot minimum similar to the Maunder minimum of 1645 to about 1715. But we're not in one now.

Actually, there was a recent development in modelling the sun, which (if I recall correctly) resulted in a model of the sunspot cycle that has a high-90s percentage match to the historical data. (The key was to model it as TWO dynamos rather than one.)

Also (again, if I recall correctly) the new model predicted that we were going into something that looked like a new Maunder Minimum, with this cycle being weak and the next one nearly nonexistent.

(Sorry I can't dig up the reference right now. Only got a couple minutes left to post.)

Combine that with orbital forcing (which has been gradually, but progressively more steeply, pushing us toward another BIG ice age since about the time humans started using agriculture and settled down to dig up stuff, including coal), and the expected exhaustion of practically-extractable fossil carbon reserves in something like four more centuries, and warming might not be our long-range climate-change issue at all.

A Maunder minimum might only cover a half-century or so. But if it brought on another "little ice age", that (at about three centuries duration) might be about right to cover the period before global freezing is more of a concern than global warming.

Comment Re:Nah (Score 1) 171

On the other hand, an electric motor can easily produce its maximum torque at stall.

Then drop off like a cliff.

Not necessarily. You're thinking of older, more basic, motor designs, connected directly to a supply (such as a series-wound motor), not a modern electrical machines with winding currents controlled by switching regulators.

Torque is proportional to the product of the stator and rotor magnetic fields, which in turn for wound magnets) are proportional to current.

In a simple motor the current is limited by the fixed voltage applied across the winding resistance, which drops as the machine speeds up due to back-EMF generated by the motor's motion.

In a switching regulator controlled winding the resistance is very low (to reduce I-squared-R losses) and the current is controlled by the switching regulator. The current at stall is potentially astronomical as a result, limited by the regulator's dwell time, not the raw supply voltage. As the motor speeds up the current (and thus the torque) can be maintained at a desired (and high) value despite the rising back-EMF, up to an RPM and back-EMF where the switch would have to be on full-time (or full half-cycle time for AC-excited windings) to push the desired current through the winding resistance.

Comment Re:Man up, NASA. (Score 4, Informative) 93

NASA lost contact with their STEREO-B satellite nearly twenty-two months ago when performing a routine test. NASA scientists are afraid to turn on the computer at this point because it may cause them to lose contact again.

What's the point of being able to talk to it if they can't turn it on and actually do stuff with it?
If they thought they lost it 22 months ago, they have nothing further to lose if it goes away again now.

Reading the article helps determine what the point is...

Seems the point is that they want to try to see if there is something they can do to point the satellite at the Sun in the 1 to 2 minutes they think they might have before the startup of the computer drains the battery and they have to wait another 6 months until the battery randomly charges up as it gets sunlight on its solar panels at the wrong angles. The sensor that keeps the satellite pointed at the sun failed, but maybe they can keep it pointed at the sun by sending commands from Earth and then they can better assess the health of the systems with more time.

Based on the article its seems they might have just enough time to give it some commands to point toward the sun and then hopefully the battery starts charging up again so they have more time to work with before it powers down.

Comment Re:Nah (Score 1) 171

Porsche 918 Spyder is 0-60 in 2.3s. Elon has a ways to go still.

On the other hand, an electric motor can easily produce its maximum torque at stall.

An electric car, with adequately sized motors, controllers, and batteries (or other power sources) should be able to drive the tires to the traction limit from a standing start to the speed where the available power will no longer sustain that level of acceleration - well over 60 MPH. This means the acceleration is limited solely by the coefficient of friction of the tire/road contact surface - a critical parameter that can be tightly tracked, during acceleration, by drive electronics akin to non-skid brake controllers.

So an electric car should be able to get the best possible standing-start rating out of any given tire technology - and be literally unbeatable in such a contest.

IMHO the only reason (pre-Tesla) electric cars had a reputation for being underpowered creampuffs rather than unbeatable sprint sports cars, is that the automobile manufacturers thought the purchasers would all be eco-freaks, more interested in mileage and ideology than performance, and designed lower-manufacturing-cost, underpowered, cars for this market.

Comment Re:Taxis are a municipal transportation service (Score 1) 442

No, they will still drive for Uber. People are desperate, obviously. The point is that no one is going to find a $12K vehicle that lasts 130,000 miles so no one is making that $13/hr. Uber is just a bottom feeder that is taking advantage of people who have no other way of making an income. The government is trying to make sure companies treat their workers fairly but apparently Uber has worked around that.

By your numbers 100,000 miles would be about how long a car would have to last to be around the highest state minimum wage. That puts many small cars in the $12k range new, and even more if you considered used cars. Seems there is plenty of room to make what the government currently considers acceptable compensation.

I am all for a higher minimum wage of $15 or even $17 per hour, but to claim the government is trying to protect workers when so many people are wage slaves with brutal and inflexible hours below what the rate Uber is paying is absurd.

It is fairly simple to figure out what the equivalent wage is for Uber drivers. Apply the standard mileage cost estimate for the distance of the requested ride and deduct it from the compensation for Uber drivers would be making. The Uber app should be doing this before the ride using the distance estimate and the minimum wage data for the state to ensure that the price is at or above the minimum wage threshold.

Comment Re:Taxis are a municipal transportation service (Score 1) 442

People keep saying that, yet obviously there cannot be too many cars on the road. Also, you want the drivers to actually have some profit potential. This is something that is not currently happening with Uber. There was recently an independent analysis and an Uber driver will make $13 an hour *IF* they only pay $12,000 for their vehicle and it lasts 130,000 miles. That's pretty difficult circumstances to operate in.

If people can't make enough money for it to be worthwhile then they won't drive for Uber and any oversupply will go out of the market. Artificially constraining supply of individual transportation choices could put more cars on the road if the best option then becomes a car rental or owning your own car versus the periodic Uber ride.

Your $13 per hour estimate is at least 30% higher than the highest minimum wage in all 50 states.

Comment Re:Taxis are a municipal transportation service (Score 1) 442

To me it seems easier for Uber just to do the work required to fulfill a cities needs like the taxi services do. Contract some drivers to wait around like the taxis do, force them to go anywhere the fares need to go, have some cars that are up to taxi standards and regulation, and have a certain number of cars for the physically disabled. Then the whole issue goes away.

So the thing that has made Uber successful is that it went around all those regulations that were put into place to protect the politically connected medallion owners. Taxi medallions are a protection racket in restraint of trade and you can't get one unless you play in local politics.

Comment Re:Uber is not "ride sharing" (Score 1) 442

Uber is simply not engaged in "ride sharing". Ride sharing is when a driver is going to make a journey, and takes one or more people with them, in return for covering their costs on the way. No money is made, and the journey happens regardless of the extra people along for the ride.

Uber is certainly not a taxi service. They aren't allowed to just pick up people that don't have a reservation in Massachusetts and most other places with a city medallion based licensing scheme. Uber is closer to a limo service that picks up people that have reservations.

Comment Re:What political compromise looks like (Score 1) 442

This tax is a very small bone that was thrown to the taxi industry who wanted far more crippling regulation of their competition. The ride sharing companies won big in this law.

Yes, and the taxi subsidy goes away after a few years and then after that state just pockets the tax to do with whatever it wants like any other tax. Also, the state hasn't decided yet how to distribute the subsidy so it is hard to say who is going to benefit. The subsidy could go towards the rich taxi owners or be give to taxi drivers as cash. To the drivers that actually might be impacted with fewer fares and lower tips and could use the money to help transition to new jobs or retire. Or what usually happens is that it could go towards some government boondoggle projects that are designed to do nothing else but give political supporters jobs for a few years at the public expense... either way there is some spreading around money which is what compromises are made of.

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