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Comments

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Limiting the Teaching of the Scientific Process In Ohio

TigerNut Re:This is good! (511 comments)

Maybe they're just not that smart....?

Sorry.

...

Perhaps they are behind where you were in terms of rote numeracy, but perhaps they have a deeper understanding of numerical objects than you did at that age?

I've spent pretty much my entire engineering career (25 years and counting) doing digital signal processing for realtime systems (voice coders, radio modulation and demodulation, GPS, inertial navigation, and graphics tomfoolery) and over time I've developed a pretty good grasp on numerical objects, algebra, and calculus, in fixed point, floating point, and modular field arithmetic. Certainly I know that stuff a lot better now than when I graduated, and I can think back through my schooling and see what was and what wasn't effective, from the basics through to a decently high level of applied math.

What I see my kids being taught, is basically a shotgun approach; but they spend so much time blasting them with alternate methods for doing things, that there is no time to teach the kids the underlying fundamentals which might help them tie things together; and the kids get confused between the different parts of the different methods so that instead of learning one or two methods fully and practicing it until they have it cold, they learn five methods superficially and forget the solution processes two days after the math unit ends.

yesterday
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Limiting the Teaching of the Scientific Process In Ohio

TigerNut Re:This is good! (511 comments)

My kids went through the same thing with the multiple methods of doing multiplication... holy sh!t did it frustrate the hell out of the younger one because once he had figured out a method that was intuitive to him, all the other methods were just, in his opinion, superfluous wastes of time. Now I hear that the "new thought" is that, for some things such as basic single digit multiplication, rote memorization is in fact the most effective method and it leaves time free to work on higher level problems.

FWIW, I did my grade school curriculum in the Netherlands in the 70's and it was like this (from a math perspective): Grade1: Addition/subtraction; Grade2: Multiplication tables. Lots of recitation to drive the numbers into your head. Grade 3: Long division. Grade 4: Fractions. Grade 5: Decimals and bigger numbers. Grade 6: Common factor elimination in fractional expressions.

My kids are three to four years behind that timeline because of the unnecessary fluffery that seems to pervade North American education.

yesterday
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Limiting the Teaching of the Scientific Process In Ohio

TigerNut Re:This is good! (511 comments)

Rote memorization is enough for math, hey? As others have already remarked, that will not work so well with division. Or algebra, or any other form of applied math. Or pure math. But I guess Ohio doesn't need to produce any math prodigies from here on. If you say "well, we can teach math methods so our kids don't have to be dumber than birds" then you have to teach logic (induction/deduction etc) so the kids can do proofs. Logical methods applied to everyday events (why do things fall?) begat the scientific method.

2 days ago
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Wikipedia's Lamest Edit Wars

TigerNut Re:Years ago, I was involved in an edit war. (219 comments)

Having recently been involved in somewhat of an edit war (well, more of a "spirited discussion"... I'm in it for the long haul on behalf of my fellow Sunbeam Tiger owners), the "reliable citation" requirement is pretty much a nuclear handgrenade. Information is considered "reliable" if it's in a printed and published book by a "reliable source" which can be taken to mean "someone that writes a lot" - regardless of whether or not their writings are well researched in general or in particular. In our particular case, even appeals to demonstrable fact were treated with disdain because it was "original research" which is not permitted.

about 8 months ago
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Boston Officials Did Not Shut Down Cell Network After Marathon Bombing

TigerNut Re:That is the best use of text messaging (211 comments)

But they're not. SMS messages are sent over the control channel on the cellular network (which is why they use much less of the system infrastructure than a voice call, which requires assignment of a voice/data channel, etc.) and they can stay fully within the cellular phone system infrastructure. No email relays involved.

about a year ago
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The History of Visual Development Environments

TigerNut Suntools (181 comments)

I used Suntools to create windowed apps on their workstations in about 1988... the first bunch were done by handcoding the panels, then someone came out with 'Tooltool' - and that basically did what most of the current form-creator GUIs do.

about a year and a half ago
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NASA Satellite Snaps First Image of Target Asteroid

TigerNut Re:Push the asteroid at the earth plz k thx bye (57 comments)

Ummm... orbital velocity is inversely proportional to its altitude above the earth. For LEO stuff, it's about 17,000 MPH (sorry about the units). If you want a faster velocity, you have to orbit lower, and then atmospheric drag would take it out within a few orbits. The moon's tangential velocity, relative to the earth, is only about 2700 km/h (or 1700 MPH).

more than 3 years ago
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In the last 24 hours, I've consumed ...

TigerNut Re:Still consuming (496 comments)

Consider also, that you need some amount of nutrients... trace minerals and some proteins that the body doesn't synthesize itself. You can be fat from overeating simple carbs, and malnourished from a lack of essential minerals at the same time.

Solution: Eat more-than-moderate amounts of different kinds of minimally processed vegetable, meats, and fruit, and then exercise off the excess calories. You can drop the meat, if you are diligent about making up the shortfall in easily available iron, other minerals, and protein.

more than 3 years ago
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$1M Prize For Finding Cause of Unintended Acceleration

TigerNut Re:Me thinks (690 comments)

OP clearly said, "... that CAN lock the wheel...", not, that *will* lock the wheel. The brakes should under all circumstances be able to provide enough torque on the wheels in order to stop the car, including being able to lock the wheels. How much of the ultimate stopping ability gets used, should be up to the driver or the ABS system. The failsafe on the ABS, by the way, should be (and as far as I know, this IS the case) that it cuts itself out of the loop and allows the driver to apply full hydraulic pressure to the brakes.

A problem with current driver ed is that people are still being taught to pump the brakes to prevent a skid. With ABS, this is counterproductive. Without ABS, it can help, but it's not as effective as threshold braking. The thing with pumping the brakes is that everytime you pump, you use some of the stored vacuum in the brake booster system. If you have the throttle wide open (as in a 'stuck accelerator' case) then the vacuum is not being replenished, and you probably have only one or two assisted stops worth of vacuum in the booster circuit, and the right thing to do is to get on the brakes HARD and then switch off the ignition, taking care not to click the key all the way through to where it locks the steering column. This is a technique that can easily be practiced in a wide open parking lot or driver's ed facility and it would save lives, or at the least some cars.

more than 4 years ago
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One Way To Save Digital Archives From File Corruption

TigerNut Re:It's that computer called the brain. (257 comments)

One thing that helps is to specifically look at damage mechanisms and then come up with a strategy that offers the best workaround. As an example, in the first-generation TDMA digital cellular phone standard, it was recognized that channel noise was typically bursty. You could lose much of one frame of data, but adjacent frames would be OK. So they encoded important data with a 4:1 forward error correction scheme, and then interleaved the encoded data over two frames. If you lost a frame, the de-interleaving process followed by a maximum-likelyhood data detector would still properly decode the data.

On a disk, a similar approach might be to use a 2:1 or 3:1 forward error correction and then interleave data over multiple sectors. If you wipe out a sector, you'd still have the data from the other sectors to recover from.

This would, of course, be implemented best at a low level on the disk drive controller. At high throughput rates, the amount of computation required for this scheme is substantial. But you don't get something for nothing.

more than 4 years ago
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My resting pulse, as of today, is ...

TigerNut ob: First pulse? (329 comments)

FWIW, the proper way to measure this is just after you've woken up, while you're sitting down or lying down...

more than 4 years ago
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Microsoft Patents Sudo's Behavior

TigerNut Re:claims (657 comments)

Remember that they all have to apply. This isn't exactly sudo.

Not correct. Of the claims you listed, 1, 2, and 9 are independent claims and can stand alone. A competitive product that incorporated just the elements of, say, claim 9, would violate this patent. A prior art product that included the elements of claim 1 would invalidate claim 1 as an independent claim, but not necessarily the combinations of claim 1 and claim 13 or claim 1 and claim 14. Unless the dependent claims 13 and 14 were subsequently judged to be obvious in light of the earlier product that demonstrated claim 1.

To an aggressive patent prosecutor, "exactly" has nothing to do with it. The approach is "We've got this patent, see? Pay us the money or we'll sue until you're out of business".

more than 4 years ago
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2 Companies Win NASA's Moon-Landing Prize Money

TigerNut Re:armadillo placed second! (110 comments)

Armadillo completed the challenge several months ago, but their landing accuracy was slightly worse than Masten's attempt. Masten completed the challenge only one day before the expiration of the contest, and was able to do it only because another competitor failed and the X prize foundation allowed Masten to use their launch window (they'd earlier used up their scheduled time slots without doing a successful flight). Armadillo didn't have time or launch permits to go back and improve their accuracy.

John Carmack was understandably disappointed in losing the $500K but is taking the long view that Masten needs the money more than they do, and they've already moved on to new projects.

more than 4 years ago
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Where Should We Focus Our Space Efforts?

TigerNut Re:The Moon (703 comments)

If I interpret this correctly, Jupiter exerts 400 times as much tidal effect as Mars does. So doubling Mars' mass would have some slight effect, but it would still be overwhelmed by what Jupiter does to us.

If you actually had to move Mercury to Mars in real (non-wormhole) space, then you'd have to figure out a trajectory where Venus and Earth were each at opposition when you were trying to sneak Mercury by those planets' orbital radius. And you'd want Mars to be waiting when you got out to that orbit, too. The motion of the four involved planets is out of synchrony enough that there's probably a suitable window every couple of decades... if only you had enough energy available to get Mercury moving and then stopped.

more than 4 years ago
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Where Should We Focus Our Space Efforts?

TigerNut Re:The Moon (703 comments)

So, you also create a wormhole between Mercury and Mars... and transport Mercury over to Mars. Since Mercury is basically a big nearly-melted metal ingot it will add some much needed mass, as well as enough metal content to hopefully give Mars a magnetic field that will be useful in deflecting the solar wind. It might take a couple millennia for the surface of the new planet to settle, but the impact energy should keep things warm for a while. Boosting Mercury to Mars' orbit and matching orbital parameters with Mars would be quite a challenge. Don't forget that you need to somehow arrange for the angular momentum of the new planet to be correct so that you keep a reasonable daylength.

more than 4 years ago
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Open Access To Exercise Data?

TigerNut Re:Why? (188 comments)

Collecting exercise data and keeping it for later analysis or comparison can be a great motivational tool especially when you're in the early stages of an exercise program. On a day to day basis it may not feel like you're getting any more fit or going faster, but you can look at a trend line based on a month's data and clearly see that you're going farther, faster, and at a lower perceived effort level (or with a lower heart rate).

Some fitness metrics are hard to quantify based on a single exercise session, so it's worth it to have data for different days, doing different things.

Disclosure: I design and test fitness monitoring products for one of the companies mentioned by several of the posters. As a group we're some of the fittest nerds around.

more than 4 years ago
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Supercharged solar cells span the visible spectrum

TigerNut Re:Wavelengths are messed up... (3 comments)

You know it's bad when paraphrasing actually corrects the "facts" presented in the tech tabloids. Thanks for pulling up the correct quote (and figuring out the correct interpretation).

about 5 years ago
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Supercharged solar cells span the visible spectrum

TigerNut Wavelengths are messed up... (3 comments)

They state "long UV wavelengths and short IR wavelengths", both in the linked article and the EE Times parent. I'm sure the researchers have it the right way around... this should be a great enhancement to the overall usefulness of solar cells.

about 5 years ago
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How Artificial Leaves Could Generate Clean Hydrogen

TigerNut Re:Since when is methanol "clean"? (101 comments)

The problem with any internal combustion engine is it's hard to control the combustion process so completely that you don't get any intermediate products out the tailpipe.

The GP said "the combustion products of methanol are relatively harmless" and that's the part I'm taking issue with - I think that because methanol can be cheaply synthesized from a number of different feedstocks, it's a good candidate for a gasoline substitute, and I've actually used M-85 blend in my race car. The higher octane number of methanol allows you to bump the compression ratio way up and gain some efficiency that way.

One of the reasons that methanol and ethanol produce fewer emissions than gasoline is that either of those alcohols is a much simpler molecule (just one or two carbons) while gasoline is actually a blend of 6- to 9-chain carbons, with varying amounts of branching. The reference "octane" molecule that has an octane number of 100 is actually a pentane with three methyl branches. So the number of intermediate products that are possible in gasoline combustion just boggles the mind, where methanol combustion really only has a couple of possibilities. I'm guessing that if methanol becomes a more common fuel in the future we'll see methanol specific catalysts in the exhaust and they will take care of the aldehyde problem... but in the meantime, methanol exhaust is not "relatively harmless".

about 5 years ago

Submissions

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Near-earth asteroid, Monday June 27

TigerNut TigerNut writes  |  more than 3 years ago

TigerNut (718742) writes "Asteroid 2011 MD was discovered on June 22 by LINEAR, and its flight path will take it within 8000 miles (12000 km) of Earth. Orbital predictions indicate that its flight path will be significantly altered by this close approach."
Link to Original Source

Journals

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Echo mileage

TigerNut TigerNut writes  |  more than 6 years ago 723.4 km, 40.49 litres. Down a bit from last time. Didn't get the oil changed but I did get new tires installed. If running Nokian WR's reduces the mileage over the old rock-hard Michelins that's just going to have to be the way it is... I also installed the new front springs (Springtech). Lowered the front of the car about an inch, and because they're higher rate, the ride is noticeably firmer.

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Echo mileage

TigerNut TigerNut writes  |  more than 6 years ago Got gas tonight. 759.5 km on 40.325 litres. I have to do an oil change pretty soon so I'll try Mobil 1 and see what that does.

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Toyota Echo gas mileage

TigerNut TigerNut writes  |  about 7 years ago I bought an Echo earlier this year in order to reduce the cost of commuting (compared to my daily-driver 2000 Tundra)... I live about 15 km from work and doing that twice a day, plus running around to pick up the kids, adds up. So far I've had to fill it up three times.

First tank, I got 720 km on about 40 litres. That works out to 18 km/litre, or about 40 US MPG, or 5.55 litres/100km.

Second tank, I went 735 km on 41.6 litres. Midway through this tank I changed out the air filter.

Third tank was mid-grade gas (89 octane RON/MON average) and I went 745 km on 41.07 litres.

So mileage is good... how to make it better? I have some lowering springs for the front (already installed some on the rear, dropped the car about 5/8 in.). Lowering the car may cut the wind resistance profile a little, and since most of my commute is done at 80 to 100 km/h that's going to matter. Synthetic lubes will start going in as I do maintenance (current odo reading is about 60,000 km) and from past experience with the Tundra that may make 5% difference. I'll keep posting mods/mileage as things develop...

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