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Comment Re: What's the deal... (Score 3, Insightful) 262

Again, using human power to turn a generator to fill a battery is a fool's errand. You're better off doing opportunistic regeneration on downhill and letting the person rest. Forcing a rider to output an extra 50 watts so that you can collect 30 watts in the battery is just idiotic. But the point was that even without regeneration, a single 26550 battery @ 98 gram and a 100 watt motor @ 50 grams is more than enough to win a race.

Comment Re: What's the deal... (Score 3, Interesting) 262

Regen on flat pedaling is stupid and goes along the lines of a perpetual motion machine. Much of the energy you pedal into the motor is lost in the form of heat and you won't get out what you put in. Reg on downhill would work and you don't need a more complex motor. All Brushless DC motors can regen when they're being forced to turn.

Comment Re:Why this is special (Score 4, Informative) 133

WiTricity has been demoing the only feasible technology (resonant inductive power transfer) since 2009. They can actually reach out a few feet without worrying about getting blocked by clothing or body parts or orientation of the receiver. But the media has forgotten them in favor of utterly unworkable solutions like Ultrasonic Power Transfer which can't go through objects and require exact receiver orientation and alignment to work.

The challenge is whether WiTricity can deliver useful range range and sufficiently shrink the receivers to be thin enough to be in a smartphone. Useful range is likely a few feet which means it's much shorter than a typical cable. We're also looking at a minimum of 50% losses which might be acceptable for a smartphone, but we know there are plenty of people who have no qualms charging their 400 watt HDTV or 40000 watt car like this.

The real revolution we're seeing in smartphone charging is USB-C with a higher Power Deliver profile. Next generation Samsung phones coming out can be charged in around 20 minutes which means a charge rate of 3C. Batteries can be pushed up to 5C to get charge times times down to 12 minutes which means 6 minutes can fill up most semi-discharged smartphones. Fast charging is far more useful than being stuck in a 3-foot area for 2 hours waiting for the phone to fill up.

Comment Re: What's the deal... (Score 5, Interesting) 262

A pro competitor at Tour de France averages 450 watts. Casual fit rider averages 220. That means having a mere half a horse power would let the casual rider win the Tour de France though you likely wouldn't be able to put in that much battery capacity for the entire ride unless you swapped the battery along the way. For competitive riders, just having a 100 watt motor that can turn on 10 minutes is enough to go from last place to first.

Comment How about sharing a little with your employees? (Score 1) 842

Notch's Mojang was supposedly different from your typical greedy corporation and it was more family. In the end he sold out and left all his employees hanging. Out of that $2500 million dollars, would it be so hard to allocate $50 million into a trust fund such that every one of his 50 employees could have an interest-only income of $50,000 per year indefinitely? Yet he couldn't even sacrifice 2% of his payout?

Comment Re:Magic Pill - Self Discipline (Score 0) 153

"what if we eat so much crap food that the wholesome hearty foods stop being produced"

There really isn't a clear line between "wholesome hearty food" and "crap food". The dosage is the problem and some foods like deserts, candy, and chips are just so calorically dense and so tasty that they're almost assured to be overeaten by the majority of people.

Comment Interviewer is extremely ignorant on power (Score 3, Informative) 92

At one point the interviewer asks "how much money you gonna save on electricity for 50 computers, $50/year"? It's clear he's never even attempted to do the math. An extra 100 watts in California is going to cost $314.91 per year at the typical rate (above baseline) of 35.949 cents per year. That's just the savings on one computer system much less 50 computers.

Comment 0.74% atmospheric pressure and trace oxygen levels (Score 1) 104

To properly test a prototype, you would need to fly a prototype helicopter (probably with very large rotor and very powerful turbine) to 33,000 meters altitude on Earth to test equivalent atmospheric pressures. The current altitude record for helicopters is only 12,442 meters.

There's another major problem posed by Mars. 96% of the atmosphere is comprised of CO2 and there is only trace amounts of oxygen. That means not only would you have to carry fuel, but you would need to carry your own oxidizer as well which adds a lot of weight.

Comment Cisco is only describing the IETF standard (Score 1) 337

"A July 1999 IETF specification (RFC 2638) discusses paid prioritization by saying: “It is expected that premium traffic would be allocated a small percentage of the total network capacity, but that it would be priced much higher.” Another specification (RFC 2475) published half a year earlier says that setting different priorities for packets will “accommodate heterogeneous application requirements and user expectations” and “permit differentiated pricing of Internet service.” (An RFC is a policy document, often accepted as standards, published by the IETF.)"

I would also add that the abstract of RFC 2474 says:

“Differentiated services enhancements to the Internet protocol are intended to enable scalable service discrimination in the Internet

Comment Re:The title is a bit misleading (Score 1) 32

Capacity matters a lot in Wi-Fi as well as cellular data. Very rarely will you see mobile devices be able to leverage 2x MIMO or better because they only have one antenna. Capacity is effective peak performance for most situations. Peak throughput is great for marketing benchmarks and occasionally real life performance when it comes to wireless bridging.

Comment Re:The title is a bit misleading (Score 1) 32

MU-MIMO does effectively offer higher speeds than SU-MIMO in practice. Since most client devices are single antenna devices and only a few that are dual-antenna, MU-MIMO effectively increases the per-client throughput by improving overall capacity. If four single-antenna clients can be concurrently served by a MU-MIMO access point with 4 antennas, each client can have up to 4 times more throughput than the same 4 clients being served by a 4-antenna SU-MIMO access point. The SU-MIMO 4-antenna AP can't speed up operation for a single 1-antenna client.

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