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Why Nissan Is Talking To Tesla Model S Owners

grqb Re:Nissan Dealers Hate the LEAF (335 comments)

Yes but what do you think this will do to their resale value after 6 years? The tesla and the volt will still have perfectly good battery packs but it's a huge question mark for the leaf considering they've already been sued over battery degradation issues.

about 5 months ago

Why Nissan Is Talking To Tesla Model S Owners

grqb Re:Nissan Dealers Hate the LEAF (335 comments)

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.

about 5 months ago

Citizen Science: Who Makes the Rules?

grqb Re:Amateur science is blocked by journals (189 comments)

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.

about 6 months ago

GNU Octave Gets a GUI

grqb Re:Is it a competitor? (166 comments)

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.

about 7 months ago

How I Compiled TrueCrypt For Windows and Matched the Official Binaries

grqb Re:Ugh, not "a software" again. (250 comments)

Translate to french and then we'll let the OP nitpick your grammar.

about 9 months ago

Fisker Lays Off Most Workers, Plans To Shop Around Remaining Assets

grqb Re:How many times do we have to go through this? (276 comments)

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).

about a year ago

iOS 6.1 Leads To Battery Life Drain, Overheating For iPhone Users

grqb Re:No problem here (266 comments)

Same here

about a year and a half ago

Woz Says iPhone Features Are 'Behind'

grqb Re:LTE (587 comments)

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.

about a year and a half ago

Forbes 2013 Career List Flamed By University Professors

grqb Re:Choice (370 comments)

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?

about a year and a half ago

Crushed Silicon Triples Life of Li-Ion Batteries In the Lab

grqb Re:Yay, another amazing new advance for batteries! (123 comments)

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.

about a year and a half ago

Ask Slashdot: How Many of You Actually Use Math?

grqb Re:Field dependent requirement (1086 comments)

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.

about 2 years ago

Ask Slashdot: How Many of You Actually Use Math?

grqb Re:Field dependent requirement (1086 comments)

To calculate the capacity used in a battery, you apply the following equation:

capacity = integral(current, dt)

So yes, this is calculus. To solve this you would use a numerical approximation to the integral, such as the trapezoidal rule.

about 2 years ago

Ask Slashdot: What's Holding Up Single Sign-On?

grqb Re:Last pass (446 comments)

I love lastpass. No need to remember login info at all (except for your master password). The _only_ problem is when using my phone/ipad, it's a bit difficult to dig up passwords.

about 2 years ago

Octave and Gnuplot Coming To Android

grqb Re:Too bad it wasn't SciPy (84 comments)


The point of Python being a "real language" doesnt apply...

Yes it does. It allows you to do something useful with your numerical codes. Maybe not needed for academia, but certainly for other industries.

more than 2 years ago

Octave and Gnuplot Coming To Android

grqb Re:Too bad it wasn't SciPy (84 comments)

I jumped from Matlab to Scipy/Numpy, skipped Octave, but I'm so happy with Scipy/Numpy that I wouldn't consider using Octave.

From a purely numerics point of view, I'm sure Octave has all the features that Scipy/Numpy has. Most of the benefits of Scipy/Numpy come from the Python programming language itself, which I have to assume is much more developed than Octave's language. Being able to write GUIs for your scientific apps using tkinter (or some other library) or reading/writing to excel formats directly or wrapping your code up using pyexe for distribution or interfacing your python code with the web or a database is just the start of the Python advantages (after a quick search I see that Octave can do some of these things, but I'm sure Octave doesn't have all the libraries that Python has).

IMHO, if scipy/numpy ever get working with PyPy, then this would truly be amazing.

more than 2 years ago

TSA's mm-Wave Body Scanner Breaks Diabetic Teen's $10K Insulin Pump

grqb Re:forced? (811 comments)

TFA didn't suggest that she was forced.It said she took the advice of the TSA worker over the advice of her doctor. The doctor's note said to avoid the body scanner, she asked the TSA worker if it was ok, and the TSA worker said yes. IMHO, a doctor has more credibility over a TSA worker in this case, I'm not sure why she didn't think so.

more than 2 years ago

Why Desktop Linux Hasn't Taken Off

grqb Re:Two Words (1264 comments)

I agree. I don't know anybody who uses a computer and doesn't rely on Microsoft Office. And crossover office is not good enough (it might work well enough, but it's not easy enough for my parents to install themselves).

It comes down to the fact that distros like Ubuntu are still too difficult to use for normal folks. Give your parents Ubuntu and see how far they get trying to play a DVD or uploading music to an ipod.

about 2 years ago

Raspberry Pi Now Has Distributors -- and Will Soon Have Boards for All (Video)

grqb Re:Electronics supplier DDoS (304 comments)

Seems the world wants a router that's had it's wings clipped and a DVI port nailed to the top.

Actually this is exactly what I want. I need something like an Asus RTN16, but cheaper. The Raspberry Pi seems to fit this bill quite nicely.

more than 2 years ago

Chevy Volt Passes Safety Investigation

grqb Re:So, they know of no fires (200 comments)

"NHTSA in fact drains the gas tanks on gas cars (including the Volt!) BEFORE they wreck them because of the danger of the gasoline."

Do you have a reference for this? Not that I don't believe you, but if this is true, GM just got a whole load of bad press which may have set back the electric car over something that was NHTSA's fault. It's unbelievable that they wouldn't test gasoline cars and electric cars on the same footing. If they first drain the gas tank then they HAVE to drain the battery before the test for a good comparison.

more than 2 years ago


grqb hasn't submitted any stories.



Energy efficiency is the key

grqb grqb writes  |  about 9 years ago

The only way to prolong oil and gas supplies is through efficiency. We have to use the 80:20 rule and focus on the areas that are the least efficienct in our lives - in my opinnion, these are cars and meat. The US has 200 million cars that consume 2/3rds of all of its oil. The US uses 25% of the world's oil, and so cars in the US alone use 16% of the world's oil [ref].

Personal vehicles require huge amounts of energy to get from point A to point B. A normal sized car has a 120hp (89.4kW) engine, which actually consumes more gasoline the slower the car is travelling, such as in city traffic, where average speeds are around 20mph with top speeds of 56mph (this is how the EPA tests city fuel efficiency at least). Using a 120hp engine is absolutely rediculous for this application. A recent study on althetes in the Tour de France shows that cyclists require only 246 watts to travel 20mph [ref], that's 360 times less energy than what is spent in a 120hp car to go the same average speed. A bike is the most efficient personal transportation device, 117% more efficient [ref] than simply walking. Of course, not everybody has a body that can generate 246 watts for a sustained period, so we must motorize bycicles, otherwise known as motorcycles, or better still, scooters. An electric scooter is the preferred way for getting from point A to point B in the city because it uses less energy than a car, but easier to sustain than a bike.

The second thing that we have to do is reduce our consumption of meat. Beef requires about 145 times more fossil fuel to grow than potatoes [ref]. David Pimentel of Cornell University calculates that it takes nearly twice as much fossil energy to produce a typical American diet than a pure vegetarian diet which works out to be an additional 150 gallons of fossil fuels per year for a meat-eater. So, the average American is using twice as much energy on a beef diet.

Finding a better way to get around in the city and reducing our intake of meat is the best thing we can do to prolong the oil and gas supplies. But, of course, running out of oil and gas is not the problem. The problem is in fact the environmental problems we will have if we use our oil and gas. The CO2 levels right now are at 370ppm. If we burn all of the oil that we know of, then CO2 levels will be 700ppm (by volume) [David Scott, International Journal of Hydrogen Research]. This is a huge problem. We have to stop using fossil fuels.


Is social growth equal to economic growth?

grqb grqb writes  |  more than 9 years ago

Every once and a while some of my friends and I have the discussion: Is social growth equal to economic growth? My argument is always yes, but our discussion is always lively and the other side always has a strong opinion and sometimes I have second thoughts.

My view is that economic growth (and of course energy growth) is closely linked to the advancement of technology that will allow cleaner water, better drugs (as in the ones that fight disease), new and better hospitals and better ways to communicate. Technology also works to reduce the price of these items and make them more accesible to everybody.

The other side of the argument though is that growth always comes at the expense of others. For instance, the life that the developed world has come to enjoy wouldn't be possible without the undeveloped world. Also, growth is by definition not sustainable in a finite bubble such as the Earth and so ultimately, growth will destroy society.

I think that technology can be used to improve the life of everybody though. For example, a better way to clean and pump water isn't required by the developed world but is needed by the undeveloped world. Technology improvements go to make those water purification systems cheaper and a side effect of technology advancement is economic growth.

These discussions never have a clear answer, but it's important to think about these things.


Saudi Oil Close To Peak - So What?

grqb grqb writes  |  more than 9 years ago The cost of oil has risen by about 50% in the last year. This time in 2004 the cost per barrel of oil was about $35, now it's about $53. The reason why oil prices have spiked is because of many things: winter requires a lot of energy to heat homes, summer requires even more energy to cool homes, a good part of it is speculation that emerging countries like China and India will require more and more oil along with North America's dependence on the sweet stuff. In general, for economies to grow, they require more energy each year which means more oil. Peak oil is what happens when oil can't be extracted at a faster rate and so the demand for oil continues to grow but the supply of oil flattens out. Respected analysts such as those at John S. Herold Inc, the first analysts to call BS on Enron, have gone so far as to predict when each of the big oil companies will peak, which they think will all happen by 2009 (Total S.A by 2007, Exxon Mobil, ConocoPhillips, BP, Royal Dutch/Shell and Eni S.p.A by 2008, ChevronTexaco by 2009). A recent report by David Coxe, an analyst working for the Bank of Montreal, said that the worlds largest oil field, Gharwar in Saudi Arabia, has started to decline, or peak. Other analysts such as Matt Simmons and Colin Campbell, the head of the Association for the study of Peak Oil (Aspo) all agree.

Of course Saudi rejects all notion that their oil fields will ever run out of oil, but promises by them to increase production last year failed to materialise and the recent 500,000 barrels per day increase was not Saudi Light crude as expected, instead the new oil was heavy, sulphurous oil that only a few refineries can use and is common when oil fields start to decline.

So, what does peak oil mean for all of us? According to James Howard Kunstler in Rolling Stone Magazine, it'll mean that we'll all have to move out of suburbia, grow our own food and accept that life will never be the way we once knew it. He also says that alternative energies won't help the US ween off of oil because they're not developing fast enough. This notion that alternative energies are underdeveloped was reiterated by a French bank, Ixis-CIB, who recently warned that oil could hit $380 per barrel by 2015. The analysts argue that this is possible because alternatives are not developed yet and the world will rely on oil no matter what the cost. The analysts also said existing new oilfield projects would not be enough to satisfy unprecedented growth in demand from developing economies, particularly China.

To help curve the dependence on oil, the International Energy Agency has also advised that all oil consuming nations remove subsidies that they give to oil. Theses subsidies distort the oil market and removing them will promote the development of alternative energies since they would appear to be cheaper.


The Importance of energy in our lives

grqb grqb writes  |  more than 9 years ago

Check out for more energy discussion.

Energy is pretty important to the quality of our lives. Just to give you a sense of how important energy really is, the BBC was interviewing somebody from Iraq a couple of weeks ago and he could have been complaining about the kidnapings, the shootings, the corruption, but he was complaining about the fact that he only had electricity for a couple of hours a day. And imagine if you didn't have electricity, what would you do? You wouldn't be able to read slashdot, that's for sure. You wouldn't be able to have a shower or flush the toilet. If we didn't have enough electricity, we wouldn't be able to build or run hospitals. Basically, the difference between the developed world and the undeveloped world is that the developed world has energy and the un-developed world has no electricity. A person in Africa has only 500 watts of power on average. My girlfriends hairdryer alone uses 1000 watts of power.

An abundant and uninterrupted supply of energy is what allows our economies to grow, it's what allows people to have jobs, earn money, send their kids to school so that their kids can live a happy life and increase their standard of living. We're at a point now where our standard of living will have to change very soon because we just don't have enough energy to maintain our current rate of growth. This is why it is important for everybody to start conserving energy. If you want your children and their children to have a better life than you did, everybody has to stop wasting energy today. It's easy to do, just turn off your lights at home, dry your clothes outside instead of in the clothes dryer, try not to drive so much when you could be walking or biking and try to buy food that wasn't grown halfway across the world. Simple things done today will go a long way to ensuring a good future for you and your children.

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