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Comment Egress Problem is easily solved (Score 1) 102

How hard can this be... when you request a pickup, the self-driving car begins driving to you, and a pin is placed on the map where it *thinks* it should pick you up. You review the pin, and move it to whatever door / street corner you want. The self-driving car then re-routes to pick you up where you placed the pin.

On future visits through the same provider, it will remember where you dropped the map pin and default to picking you up there. If you choose to move the pin again (say, you're coming out of a door the other side of the building) it then obeys that, and the app prompts you to give "friendly" names to those two points. Next time you choose to be picked up from the same vicinity, you are presented with a simple dropdown that offers you three options:
"The Green Door"
"The Other Side With The Cafe"
"Choose Another Location"


Am I missing something that makes this problem unsolvable with today's tech?

Comment Re:Science (Score 2) 61

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) 61

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.

Actually:
  - 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 2) 289

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.

Science

Bill Nye Explains That the Flooding In Louisiana Is the Result of Climate Change (qz.com) 289

Reader mspohr writes: Our favorite science guy has an interview (and video) in Quartz where he explains how Louisiana flooding is due to climate change:
"As the ocean gets warmer, which it is getting, it expands," Nye explained. "Molecules spread apart, and then as the sea surface is warmer, more water evaporates, and so it's very reasonable that these storms are connected to these big effects."
The article also notes that a National Academy of Sciences issued a report with the same findings: "Scientists from around the world have concurred with Nye that this is exactly what the effects of climate change look like, and that disasters like the Louisiana floods are going to happen more and more. According to a National Academy of Sciences report published earlier this year, extreme flooding can be traced directly to human-induced global warming. As the atmosphere warms, it retains more moisture, leading to bouts of sustained, heavy precipitation that can cause floods."

Comment Re:You know I could get in to something like this (Score 1) 81

Well personally I've been quite happy with a number of the new features. Also security isn't irrelevant to me, given that I do work to keep my device secure by updating it, by running security software, and be screening what I install and only installing things I need.

I am talking about MY interest in something and ya, having new versions of software is something that I consider. If I'm getting a new device that is something I want.

Comment Re:The end justifies the means (Score 4, Insightful) 293

Somewhere around 20-40% of the info in these documents will turn out to be wrong or misleading in some critical way.

I'm sure that will be a great comfort to the alleged witches as they drown.

Also, just because some personal data is correct, that doesn't mean the entire world has any right or need to know. People suffer unfair discrimination or worse because of perfectly legitimate personal matters all the time, which is the most compelling argument for the importance of privacy.

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.

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