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Comment Re:RPN calcs- esp 35s (Score 1) 328

Thanks for the update.

It's the successor to the 33s, which had an odd keyboard but was otherwise ok, which in turn was the successor to the 32S/32SII. Those are still quite capable calculators if you find one around.

Here's that odd keyboard. Geez, form over function is bad enough; it's not supposed to actually hurt your eyes...

The 35s is allowed on a number of tests where fancier calculators aren't, including the NCEES. Not the cheapest, but capable. Its support for polar complex numbers covers what you seem to be asking for.

The wiki-p page for the 35s. Wow! - the first time I've seen this; looks like their classic design. Is HP back when it comes to calculators? In the Reception section of this page, among other things, we have: "While welcoming the improved handling of complex numbers compared to the 33s, the incomplete support for them has been criticised."

Notice that on the above wiki-p pages for the 33s and 35s, although in the right-hand sidebars it says "Manufacturer: HP", it also says "Design firm: (company name)". It does not say that for the 32s or the 42s. Can the sort of dedication to a product line that we miss be contracted out?

Enough people considered the 42S to be the best calculator ever made that it goes for absurd prices on ebay.

FWIW, back in the day I had a 48s - but sold it and bought a 42s because I wanted something I could more easily nudge around a desk and use 1-handed (and for nontrivial stuff I would use desktop apps). It's still within reach right now. From my cold dead hands!

Comment Re:In the footsteps of Arduino (Score 1) 42

...where-as the AVR does not have a debug protocol or JTAG, you have to replace the chip with an emulator. Have fun soldering all those wires from your emulator to your application board!

What about debugWire? Not full-blown JTAG, but it is an in-circuit debugging interface (uses the RESET pin). I believe it's now on all but the simplest of devices.

Comment Re:Can't wait (Score 1) 67

(also replying to belthize above) Earlier today I was toenailing rafters with a hammer, and yet right now I'm still glad I can rest my forearms on my desk and nudge the mouse around. (And no, it's not because I'm tired or out-of-shape!)

The difference with physical labour is that it's usually gross motor skills in short intervals. Also, you're usually benefiting from the interface being not only haptic but able to resist and support real forces, e.g.: to place a block, you only have to wrestle it in the plane; it's being supported vertically by the wall it's sitting on.

OTOH, using the Minority Report interface for the wrong task would demand fine (or medium) motor skills w/o the usual bracing of your hand against the work, piece of gear, or the tool itself when in contact with the work. So neither physical labour nor many hands-on crafts would make you immune to gorilla-arm syndrome.

Maybe only ballet could prepare you properly? But you may still want to brace your elbow on your chest while you point. Of course, this is just another case of "where appropriate", i.e. applied to quite particular industrial and/or creative tasks.

Comment Re:TAS (Score 1) 283

But if you like Kzinti, read the shared-universe series The Man-Kzin Wars from Baen Books, where Larry lets other people play in a small section of his Known Space.

Seconded. I have the first 5 or so of these books; each contains 2 or 3 novellas by various authors, some self-contained, some continuing in later books. Damn good reads!

In a preface or two, Niven tells how contributions had to stay true to the canon. Nitpick: I wish that included the cover art - Kzinti don't look like tigers; they're orange, barrel-chested, and have bat-wing ears, tanj damnit!

Comment Re:A modern drawback (Score 1) 105

Re. Schmartboard adapters, here's a 0.5 mm pitch QFP to 0.1" adapter. It's 10 bucks. OK, a BGA one is $45. But still, what are you looking at that you don't find inexpensive enough? What family of devices are you wanting to work with?

Aside from hacking some existing proto- or dev-board with the device you want to work with (e.g. with short patch cables or headers to a breadboard or other daughter proto-boards), you should consider just biting the bullet and learning to design and solder your own SMT PCB's.

Sure, you may not have a completely tested and threshed-out design on a rats-nested breadboard to work from, but OTOH designing and having fabbed simpler double-layer (or even 4-layer) moderate-speed boards is now very accessible*. Part of it is accepting that for projects you're serious about (or, of course, stuff that's "work"), the first board may not be final, so go ahead and make one that gets you up and running with an initial design (which you have the experience to be confident in) but for which you may still be patching interfaces to, etc. If you know it's not final, you can save a bit of money by skipping the silkscreen and soldermask.

*Depending on what you're doing, you will have to become acquainted with proper layout techniques re. EMI/noise to some degree.

Comment Re:Wearable computing... (Score 1) 236

Ever tried to use a watch in the winter? Tug glove down, pull-up wrist of coat, pull up wrist of jumper, pull up wrist of thermal underlayer, dig for watch.

That's what the new SmartRing is for! Tells you what hour it is! Flashes when there's a message on your smartwatch, which you then check to see what's on your smartphone!

Comment Re:Won't come close to Apollo 13 (Score 1) 97

Oh, and "micro-gravity" stems from _all_ mass, not just Earth.

To clarify, according to the Wikipedia page, most of the non-zero g forces in a microgravity environment are due to tidal and other "differential" effects. From the figures given, the effects of gravitational attraction between, say, an object and a massive part of a space station (or, I suppose, between a station and docking craft) are less significant in probably most situations.

Comment Re:Won't come close to Apollo 13 (Score 1) 97

Had to work this out... 1 lightyear ~ 1e16 m, 1 solar mass ~ 2e30 kg, acceleration due to gravity = GM / R^2. So acceleration due to sun at 2 lightyears ~ 7e-11 * 2e30 / (2e16)^2 ~ 4e-13 m/s^2 ~ 4e-14 gee. Yep, pretty much unmeasurable.

However, according to Wikipedia the sun is about 30 000 lightyear ~ 3e20 m from the galactic core and is moving at about 240 km/s = 2.4e5 m/s relative to the core, so if we simply assume that's fully tangential, radial acceleration a = v^2 / R ~ 2e-10 m/s^2 ~ 2e-11 gee. That would be the acceleration due to the gravity of the rest of the stars in our galaxy, and is 500x stronger than the above figure (but as a force m*a on a person still probably not directly measurable).

Of course, getting yourself out there wouldn't really get you "more zero G" in practical terms, since as others have pointed out, free-fall is free-fall. (Although you wouldn't have to worry as much as to whether your trajectory will hit something, and there would probably be effectively no "microgravity" tidal-like effects.) But I'd better stop now before I start discussing the Equivalence Principle...

Comment Re:Why is this a story? (Score 1) 194

...And a bigger problem is that teachers nowadays focus more on teaching the procedures than the concepts.

...which is obviously related to the problem of elementary teachers not having enough of a math background, on average. From the linked WSJ article, regarding a discussion with the head of a tutoring firm:

Many students are confused by the terms often used to describe fractions, such as "common denominator," so tutors offer clearer, more concrete names.

Denominators, for example, are "the name of the fraction," rather than simply "the bottom number"... This helps kids understand why they can't add ½ and 1/3 and get 2/5, he says. Tutors explain, "One apple plus one apple is two apples. One banana plus one banana is two bananas. But one apple plus one banana isn't two banapples."

Kids have to resort to extra tutoring to hear that comparison?! Something like that should come up several times on the first day of doing fractions. But perhaps not, if the teacher is following the script of that flashy new unit, without the creativity (or confidence?) to "teach between the lines".

As others have pointed out, a good teacher will use many real-world examples of fractions - to focus too much on this vs that, or to continually revamp / reinvent math instructional methods, is to try and solve the wrong problem.

Comment Re:Please ruin it like you did Star Trek (Score 1) 376

...THAT was a big plot hole, albeit not as big as time travel related ones, which are endemic throughout the original movies and series.

Indeed - and all those "gadzooks we've been wormholed to $SOMEWHEREPLACE" trips (and trips to "fix the timeline") leave the Trek universe with so many patched-up potential paradoxes that someone only has to look at someone wrong and the whole thing will collapse into a fuzz of GR technobabble.

Comment Re:Must we call him a genius? (Score 1) 163

The vast majority of people can actively enjoy music in the background *and* pay attention to what they're doing -- it doesn't become "white noise" just because we're not focusing all of our attention on it. Music also actually helps us enter the 'zen' state that results in markedly improved performance; at that point, we'll be focused on the task, but fall right back out of the zen state if someone shuts the music off. That's why music is commonly found playing in situations that require a great deal of concentration: performing surgery, playing a tough video game, writing fiction, etc.

For me it is the exact opposite, and I'm coming to accept I'm in the minority. If I need to concentrate (e.g. soldering, writing code, or doing math), I need silence. Even when I worked as a bike mechanic, I had to exact compromise on the radio volume from my coworkers*.

*The only way I could explain it was that it "grabs my brain" or "pushes things out of my brain". Say I'm working on a bike: I notice something I must check next, after I'm done what I'm doing. Then I notice something else that must be checked, but any time later. (I'll jot the 2nd one down when I get the chance, but right now I can't let go of what I'm in the middle of.) Now I realize I need to choose a more appropriate tool for what I'm doing right now (notice my stack is now 3 deep), so I turn to the workbench, just as the radio blares out the even more annoying part of that song or a sponsor starts yelling about used cars, and - BLAM, I've lost one of those 3 items. I have to go back physically and mentally to the same point and quickly rerun things to try and get it back. In short, it breaks the continuity or "flow" and I'm less efficient. (And more "on edge" too, as I try to tune it out.)

I know it also reduces my skills of observation - e.g. when doing something mechanical, noticing defects or that a manual process didn't go as properly as it should have.

And forget about doing anything clerical - most music (or esp. annoying commercial radio) "pushes numbers out of my brain" that you need to keep a hold of for several seconds at a time.

At another workplace, a colleague in the next cubicle was working on ACAD drawings - while rocking his head to something heavy metal-like. I just can't get that. Meanwhile, I'm working on some technical document, and had to ask him to turn it down.

Aside from the volume, in general it may be that music with vocals is worse for this effect.

Comment Re:So.... (Score 1) 169

Exactly as well. I did have a few profs that did an excellent job within the usual lecture mold, but I have wondered about a format where the lecture hours were more tutorial-like. The main reason is: when do you learn something, really learn something? Sure, while following some derivation in a lecture you may think "oh, cool"; but the true "aha" moments come at unexpected times later when, say, you're working a problem (not a turn-the-crank type) or reading another treatment of that tricky section, etc. - the key point being that you're in a more self-directed or iterative mode of learning when it happens. A tutorial format where one can focus on or re-approach particular issues, rather than a monolothic linear lecture, would seem to be more consistent with this.

Comment Re:So.... (Score 1) 169

Quite. Students have always been told to do pre-lecture reading, but it's very rarely enforced. In fact, all my lecturers seemed to run on the assumption that we wouldn't, so lectures gave the information from the ground up, rather than starting where the reading left off.

...which induces one to not read ahead of time, since (a) you're going to have to be there for the entire from-the-ground-up hour anyway (for that odd gem or comment you don't want to miss), so you may as well spend the time on another problem set that's due; and (b) doing the assigned problem sets (in what I called "assignment cloning sessions", which you'd better latch onto even if you want to do them yourself) (and exam based on the problem sets) sometimes seemed a bit orthogonal to understanding the material at the level of dedication that may include pre-reading.

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