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Comment: Re:Nissan Dealers Hate the LEAF (Score 2) 335

by grqb (#46328911) Attached to: Why Nissan Is Talking To Tesla Model S Owners

If I were you I would consider the battery thermal management system in the electric car. It might be a bit technical for most people, but it has a direct impact on how many years the battery will last. The Leaf doesn't have a thermal management system. The Tesla and the Volt both have sophisticated ones.

Comment: Re:Amateur science is blocked by journals (Score 1) 189

by grqb (#45818251) Attached to: Citizen Science: Who Makes the Rules?

I agree. The public needs to have access to these journal articles. Now that I've left academia I don't even have free access to the articles that I wrote myself. (of course I kept the PDFs but if I ever lose them I'd have to pay $40 for every article that I wrote). It really does hold back progress.

Comment: Re:Is it a competitor? (Score 4, Insightful) 166

by grqb (#45805927) Attached to: GNU Octave Gets a GUI

Most of those jobs are for "application engineers" and not developers. An application engineer is a little like tech support and a little like sales. They will work closely with existing customers to make Matlab work for their customers application and they'll also try to upsell new features.

Octave wouldn't have the same type of support structure but might have similar numbers of man power contributing to the development.

Comment: Re:How many times do we have to go through this? (Score 1) 276

by grqb (#43378813) Attached to: Fisker Lays Off Most Workers, Plans To Shop Around Remaining Assets

I agree. The impression that I have from Fisker is that their product was not well engineered compared to competitors like Tesla. The Fisker Karma looked nice but they did have quality problems. Using lithium-ion batteries from A123 was one of their mistakes (even before bankruptacy, A123 had problems).

Comment: Re:LTE (Score 1) 587

by grqb (#42843843) Attached to: Woz Says iPhone Features Are 'Behind'

To be honest I wouldn't say apple is behind the times when it comes to something like this. They sacrificed this feature to make the user experience better due to battery life limitations. You could argue that they should have anticipated this by coming out with a larger iphone, but IMHO, i dont want a large phone. The impression I get about apple features is that they are conservative with new features because they are paranoid about breaking the user experience, mostly battery life. I don't have first hand knowledge but I'm sure those early android LTE phones didn't have very good battery life.

Comment: Re:Choice (Score 2) 370

by grqb (#42490555) Attached to: Forbes 2013 Career List Flamed By University Professors

Here's an easy analogy: being a professor is pretty similar to running a small business. You attract funding, you manage cash flow, you pay your employees and you produce goods (ie. in the case of a professor, the goods are research output). If you don't do these things well, your lab will go bust, just like a business would. Nobody would argue that being a business owner is stress free even though you don't have a boss breathing down your back, so why would being a professor be stress free?

Comment: Re:Yay, another amazing new advance for batteries! (Score 1) 123

by grqb (#41862049) Attached to: Crushed Silicon Triples Life of Li-Ion Batteries In the Lab

Battery materials are reported in mAh/g because this way they are independent of the battery size. You could stuff say 50g of this material into a battery meant for a car or 1/2g of this material into a battery meant for testing in a lab and you can roughly estimate the energy storage abitlity of the material. Both of these cells will have a voltage of about 3.7V on average. The units of mAh/g tells you about the amount of lithium that can be stored by this particular material so that it can be compared against other materials on an equal basis.

Comment: Re:Field dependent requirement (Score 0) 1086

by grqb (#40938253) Attached to: Ask Slashdot: How Many of You Actually Use Math?

Huh? You don't consider numerical methods that approximate integrals to be true calculus?
This is true calculus. You don't need to know anything about the future voltage curve or current, just the past.

This is the equation to calculate capacity consumed in a battery (which is a numerical approximation to an integral):

capacity consumed = capacity at last check + (current + current at last check)/2*(present time - time at last check)

The equation above is the trapezoidal rule ( applied to the integral in my first post.

I hate to pull this one out, but trust me, I'm a battery scientist that makes mathematical models of batteries for a living.

All life evolves by the differential survival of replicating entities. -- Dawkins