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Comment But why a dome? (Score 1) 62

The article lists the requirements for the structure, which include things like massive air flow, high heat density, high electrical power density, etc. Constraints like that tend to point toward structures with high surface area to volume ratios. A sphere (or section of a sphere in this case) has the MINIMUM surface area to volume ratio. So why would you want to put this structure into a dome rather than a long, low building?

(And if you really insisted on getting all fancy, architecturally, you could still make the long low building into a ring and retain most of the advantages.)

Comment Re:The Parachute Will Work (Score 5, Insightful) 55

I saw the live press release on nasa.tv (highly recommended). The principle scientists involved recognized the parachute failure, but emphasized that this is unknown territory, and the mission objectives -- which were to make an attempt and gather as much data as possible about that attempt -- were fully realized.

Yes, the parachute failed. The vehicle was going something like Mach 2 at the time, having successfully aerobraked from Mach 4.7. They got excellent video of the entire process, and only four days (or something like that) after the mission, already had revisions on the parachute in mind to prevent such failure.

This was the first of THREE planned tests. Was the mission successful this time? Absolutely not, if you expected to have a first time test succeed. But if you were looking to gather data on potential failure mechanisms, it was an overwhelming success.

And, it should be noted, the deceleration inflatable ring (which has some kitchy acronym) worked very well, and importantly, they got good data on the design and how much it deviated from perfection (1/8 of an inch deflection at Mach 4.7 ... I dare anyone to do that with rigid materials, let alone inflatables). And the blute (the droge which pulls out the main parachute) worked entirely as intended. The downside? The shape of the parachute apparently needs to be more rounded.

They are exploring entirely new territory. Who here really, really, thinks that every such testing and development mission is going to be successful? Anyone? Raise your hands, I want to see, because NASA would love to hire engineers (hell, screw NASA, *I'd* hire engineers) who have that level of talent. They're called experimental missions because the outcome is not known.

Comment Re:We're only talkin' two Red Line subway stops (Score 2) 205

Yes, it is two subway stops. And about 30 minutes of transit time each way, once you factor in the time to walk to and from the subway stations, the unpredictability of the Red Line frequency (although I must admit it has gotten heapsload better in the last few years; and major kudos to that skunk works project that brought the T administration kicking and screaming into the 20th -- yes 20th -- century by implementing time-to-next-train displays). While not an insurmountable impediment, it does mean that any given inter-campus class requires an empty slot before and after in your schedule. That too is not insurmountable, but now you're talking about two big impediments, so the motivation to attend physically has to be really high.

Here's an example from personal experience. MIT students are also allowed to cross-register at Wellesley College. As a male student at MIT, the motivations for doing so were really high when I was in school. I registered for an astronomy class at Wellesley, with the additional chance of getting some telescope time that I wanted almost as badly as to be around college gir-- I mean women. Even with all those attractions, I dropped the class because it was such a huge time sink when you factored in travel time (that and the class I had registered for was teaching stuff I had learned on my own as a kid by reading books).

So, two subway stops? Not quite close enough unless you have really motivated students. Internet attendance of lectures with once per week recitations that required physical attendance? That would work better.

Comment Re:Don't Call it Waste (Score 0) 71

At the prices medical-grade titanium goes for, it is most certainly not wasted. The machined Ti is reclaimed (or at least it would be if I were in charge). Stating that there is 80% waste is marketing hyperbole. A fairer comparison would count the unsintered powder in the 3D build machine, and would end up being unfavorable to the 3D process.

But if you're in the business of making replacement body parts, you might well be starting with a generic titanium casting (or one of a series of different sizes) and machining it down to fit. Artificial hip joints are sometimes made that way.

Don't get me wrong, 3D printing makes a lot of sense for highly-custom items... although one needs to worry about the potential infection and reaction issues given the inherent porosity of sintered material that give purchase for pathogens, and lots of surface area for irritants that will slowly leech out.

Comment Buy a Kinesis instead (Score 1) 82

1. "All the Keyboards" didn't apparently include a Kinesis. At least there isn't one visible amongst the few photos linked.

2. The new keyboard looks an awful lot like a Kinesis.

3. I stopped watching the video after the first 10 seconds because it was too awful.

4. The web site shows a keyboard with what appears to be a metal case, and the text references aluminum, as does the blog. Wood isn't part of the equation here. Maybe in the early prototypes, but not in the production models, apparently.

5. Any decent keyboard driver (and there are lots of aftermarket add-ons) support macro definitions. Nice that this new keyboard supports it, but certainly not a defining characteristic.

6. Just go buy a Kinesis. It's been in production for a long time, and they work great.

Comment Re:Same business model, different business (Score 1) 401

"The little yellow rabbits with the red eyes told me to cancel. There are so many of them here now."
"I need to tie up some loose ends before heading over to the Comcast office with my AK-47."
Switch to German. If the CSR speaks German, switch to French. Then Portuguese. Russian. Greek. Etc.
"Oh, that's really interesting, please tell me more [wait for reply] REALLY? That's so interesting. Please tell me more. [wait for reply] I didn't quite understand that, could you repeat it? ..."
"Zorg said it must be done."
"The CIA keeps sneaking into my house through the Internets to read my mind while I sleep."
"What did you say your name was? [type, type, type] OK, then, I've updated your Facebook page for you. Hope you like the new photos -- boy that sex toy sure is big!"
"Oh, can you wait a sec? There's someone at the door." [leave phone on table by loud, badly tuned radio, and walk away for a good 40 minutes]
Go to the bathroom and make appropriate noises as if defecating with some difficulty and repeatedly flushing, but continue to hold the conversation.
Hand the phone to your 5 year old.
Aim an air horn at the microphone.
"Each time I try to move the cable box, the electrons keep spilling out."
"When I use the Internet at my friend's house, it's OK, but at my house, all the photos are upside down."
"I need to spend more special time with my hamster."
"I'm dead."
"I've just had enough of the sparks."
"It interferes with my hair dryer."
"This chick said she'd sleep with me if I cancel my cable."
"The Internet is too big."

Comment Re:IKEA's name is the big deal (Score 1) 207

Tax avoidance makes more sense than any other speculation in this discussion.

Were IKEA organized as a normal for-profit venture, then anyone with half a brain at IKEA would see the utility of IkeaHackers and do one of a handful of things:

1. Buy them outright.
2. Obtain favorable advertising terms in exchange for licensing (eg, ikeahackers gets to keep running ads, but 50% of the spots must be filled with IKEA adverts, and sales-active links to the official items mentioned in each article must be included).
3. Think they're cute, and provide gratis branding coaching (including direction on proper use of their logo, precise color usage, etc) in exchange for disclaimers, and big, obvious links back to IKEA.
4. Sign an exclusive advertising deal: ikeahackers.com gets to keep operating, but must only carry IKEA adverts, with some affiliate payment structure for completed sales that originate on ikeahackers.com so that the site can continue to live on.
5. Similar mutually-beneficial arrangements . . .

IKEA have an enthusiastic fan base who, inspired by reading the blog, will likely go out to buy more IKEA product. This is not just a good demographic, but a great big juicy one. These are the people they *want* shopping in their stores, the people they *want* to reach through media campaigns.

So why turn them away? The only conditions that come to mind are when bringing the web site into the fold has larger, more threatening implications to the corporate structure, as the parent post suggests.

Comment Re:Might be the perfect tablet for academia (Score 1) 136

Paper. I have lab notebooks from my undergraduate years (through the present) that I refer to, because it's easy to do so. If I need to find something, and don't recall exactly where it is, a simple flipping of the pages, and I've found it in a matter of seconds.

Call me a luddite, but electronic lab books don't have sufficient usability yet. My post-doc uses one, and he's far less efficient with it (and writes much less as a result) than I am with pen and paper. Importantly, human memory is at least partially (some would argue primarily, and I wouldn't dispute that) visually based, and not having that aspect of where you wrote something on the page, or in what color ink, or with what size handwriting, etc., makes a big difference to usability. The closest I've seen to viable electronic notebooks are the specialized pens that have small internal cameras that require special paper to use. Last I checked, though, they were prohibitively expensive compared to a traditional pen and lab book.

Pen and paper have had thousands of years of development. It's going to take a while longer before the electronic version is usable.

Comment Re:Uh... (Score 1) 208

I don't buy the thermodynamic argument. That's an epiphenomenon (i.e., correlation not causation).

Basic mathematics does not consider time. Nor does it really consider sequential ordering properly until it deals with the notion of state, State begets the field of Computational Theory. Before a proper wrangling of the ideas at the core of Computational Theory (as embodied in Turing Machines, for example), there was a horrific thrashing-about that was particularly inelegant, such as the attempts in First Order Logic to capture the meaning of state.

Now, when you talk about infinity, you are effectively saying that results from Computational Theory are being computed by a machine that takes zero time to get from one state to the next. Nothing in the physical universe takes zero time, and so infinity is considered to be ill-supported by Nature. That's the crux of the Constructionist objections.

Now why should mathematics be beyond time? It describes space pretty well. Why should time be exempt?

Comment Re:Uh... (Score 1) 208

There are a fair handful of constructionists (aka finitists, or number theorists who do not like infinities) who would care to disagree.

Although I'm not a constructionist, I am related to one by birth, and nearly always find something off-putting about mathematical arguments that rely on infinities. Sure, they're fun to play with, but reasoning about them means you're essentially being fast-and-loose with time, and I've not been convinced that's OK.

Comment Re:How to get the lenses (Score 1) 83

Feh. So the news article says he's using industrial grit. The presumably more authoritative arXiv paper states

Ball Lenses.
The ball lenses used in constructing Foldscopes included material types borosilicate, BK7 borosilicate, sapphire, ruby, and S-LAH79. The vendors included Swiss Jewel Co, Edmund Optics, and Winsted Precision Ball. Part numbers for some select lenses include: 300m sapphire lens from Swiss Jewel Co. (Model B0.30S), 200m sapphire lenses from Swiss Jewel Co. (Model B0.20S), 2.4mm borosilicate lenses from Winsted Precision Ball (P/N 3200940F1ZZ00A0), 300m BK7 borosilicate lenses from Swiss Jewel Co. (Model BK7-0.30S), and 1.0mm BK7 borosilicate lenses from Swiss Jewel Co. (Model BK7-1.00). Note that half-ball lenses from both Edmund Optics and Swiss Jewel Co. were also tested for use as condenser lenses for the LEDs.

So they aren't exactly industrial grit, but very tiny lenses that look like they were originally intended for the telecommunications industry. The question of how does one get these lenses is answered by, "pick up the phone and call one of the listed suppliers who specialize in micro-spheres of clear, hard stuff."

Comment Re:How to get the lenses (Score 5, Insightful) 83

If you read the article (I know, I know) you'll learn that he uses industrial grit, also known as glass beads, which are tiny bits of glass that are reasonably spherical and ridiculously cheap. The quoted lens cost in the article is $0.17, but unless I'm misunderstanding something, like how special the grit is that he's using, or what kind of secondary selection process is required to pick out beads that will make good lenses, that should be closer to 0.17 cents, not 0.17 dollars.

Comment Re:What would NASA say to it? (Score 1) 166

So because they are no longer new, we should abandon the Mars Rovers, Cassini, the Viking probes, and other projects just because they are beyond their mission lifetime?

We should stop measuring lunar albedo just because it's always the same? We should stop the pitch drop experiment? We shouldn't have measured the cosmic background radiation to look for spatial variations? We shouldn't have measured continental drift because it can't possibly happen and mountains don't move? Just because something appears static (and without comparing against previous measurements, we have no means for verifying that), does not mean it isn't changing over longer time scales that are still very important.

I'll repeat my thesis: we are so data-poor about the solar system that the feed from any single working probe is vital. The cost of receiving data is trivial compared to the cost of construction and launch.

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