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Comment Re:Uh... anyone check electric grid capacity? (Score 2) 327

The best cars in the World Solar Challenge average about 100 km/h, for 9 hours a day, using the full days' sunlight. (They start charging at dawn, finish at dusk, but Challenge rules only allow them to drive for 9 hours a day.) So that's 900 km per day, every day, off 6 square metres of cells. A parking space is at least 12 square metres.

Comment Self-reproducing (Score 1) 83

The RepRap project is an initiative to develop a 3D printer that can print most of its own components.

Until now, RepRap have been stymied by an inability to print any of the systems that control the printer. But, no longer! Simply print a mechanical computer to drive your 3D printer, and the goal of a self-reproducing device will be fulfilled!

Might be large, though.

Comment Re:I travel with 2 27" apple cinema displays... (Score 1) 141

relative light weight

In my experience, custom-made transit cases of this style (plywood panels with thin aluminium sheets over them and aluminium corner and edge pieces) are heavier and more expensive than a similarly sized Pelikan cases.

If you left out the plywood and used something like Ayres composite panels, you could save a lot of weight, though.

Comment OKCupid does something like this (Score 1) 193

Dating site OKCupid does something like the negative of this:

  • Anyone can become a user.
  • Any user can post a profile, photo, etc.
  • Any user can flag a profile, photo, etc. as inappropriate.
  • Flagged content goes to a subset of those who have volunteered as moderators. (Only experienced users may moderate.)
  • Moderators mark the content either for deletion or retention.
  • Items marked by enough moderators for deletion are given a second look by OKCupid employees, then deleted where appropriate.

This is not terribly different from the moderation system here at /. in that all content is initially visible and is only moderated after publishing. But it's similar to the academic case in that items go to anonymous peer review and then to a non-anonymous editor for final decision.

Comment Re:Killing anonymity (Score 1) 88

Perth SmartRider does indeed use MiFare Classic, and the cards are indeed insecure. But there's some server-side smarts which will (eventually) notice a cloned card, and deactivate it. I expect it also (eventually) notices if you top up your card yourself for free.

The idea is that although the system can be exploited at a small scale, it isn't worth the hassle. Provided their server-side stuff prevents exploits going commercial and becoming widespread, it's good enough.

Comment Re:Peak demand for oil happened in 2008 (Score 1) 398

Yep; that's why I said "oil dug up out of the ground". I agree that there's a very good chance we will continue to use gasoline/petrol and diesel in applications like transport for quite some time, by manufacturing them from something other than fossil oil. That something else might be coal, or bioreactor algae, or some other option.

Liquid hydrocarbons have a fabulously high energy density and are easy to transport, internal combustion engines have a lot of desirable properties, and we've got all this existing infrastructure.

But the stuff dug out of the ground? Gone in a century.

Comment Re:Peak demand for oil happened in 2008 (Score 1) 398

I'm hoping for a very slow slide down the oil production graph instead of a sudden drop to nothing

Typically production of a limited resource is approximately symmetric, so you can expect production of oil to tail off over about the same time period that it ramped up. There's no point at which we "finish" the "last" of it, but expect us to be mostly done with oil dug up out of the ground somewhere in the 22nd century.

https://en.wikipedia.org/wiki/Peak_oil

https://en.wikipedia.org/wiki/Hubbert_peak_theory

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