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Comment Kindness of strangers? (Score 5, Interesting) 101

(Caution: I read the article.)

Sounds like a pretty good idea, all-told. An engineer does good with his PhD thesis, starting a non-profit company to create inexpensive MEMS-based earthquake sensors that use the cellular network for communication. Makes them cheap enough that he can deploy them all over the place. But who pays for upkeep? Who pays for electricity?

Here, we get to the problem: he depends on the kindness of strangers to bolt these small devices to their wall and plug them in -- permanently -- to an available outlet. Why would sufficiently many people do that? And since the dwelling turnover in California is so high (at least compared to the other cities I've lived in, CA residents seem to switch apartments at a furious pace), what's the plan for transferring ownership / upkeep agreements? WIth tens of thousands of sensors, that sounds like an ongoing, permanent customer service management nightmare.

Don't get me wrong, the idea's a good one. It might be easier to convince people to download an app that looks for tell tale acceleration signatures of a quake. Cell phones already have location information and the owners are already motivated for other reasons to keep them charged and maintained. The potential downside is that the data quality is likely much lower since cell phones aren't rigidly attached to terra firma.

But that, then, suggests perhaps a dual layer system that includes some company-maintained (he's running a business, after-all) sensors, say installed in a less dense mesh on telephone poles or street lights where they have ready access to (a) rigid fixation, and (b) electrical power, and, importantly, (c) won't be screwed with by the dog / kid / furniture mover. Moreover, upright structures with high aspect ratios, like streetlights, likely amplify ground movement, making detection that much easier. Use that streetlight network for coarse sampling, and the voluntarily downloaded apps as lower-grade, spatially denser sampling. And then, as Randall Munroe suggests in XKCD, monitor the twitterverse for earthquake terms. The apps have next to zero running costs, perhaps only sporadic development and a download server somewhere, the mesh network installation costs can be split between local municipalities, the state, and the NSF, with a maintenance contract to the company from the state. Heck, I'm starting to talk myself into a good business plan!

But depending on the kindness of strangers to install and maintain a thing in their house? Not such a good idea.

Comment Ring of Fire? Not Sphere of Fire? (Score 2) 37

I'm not an astrophysicist. I'm not even a physicist. I never took quantum mechanics. I don't understand GR, and many of the often-discussed effects completely baffle me. But given that accretion disks are, you know, BIG, why do all of the standard depictions I see of black holes make them look black? Shouldn't the accretion disk, spewing tons of energy as it heats up on the death spiral, obscure the black hole? Black holes -- at least ones like at Saggitarius A -- have huge accretion disks, much, much bigger than the event horizon. So won't it just look like a fuzzy bright area?

Comment Re:Instead... (Score 1) 356

I have a feature phone. I spend 40 minutes a day, over two stretches, where I'm away from a full-sized keyboard and large, readable screen. For my lifestyle, I fail to see the need to fill those additional minutes with connectivity when I might otherwise, you know, enjoy my immediate physical environment!

And feature phones still have the attractions for me that are mentioned --- relatively rugged, reliable, instantly resettable by popping out the battery, inexpensive to replace if lost or inadvertently damaged, etc --- even though I'm not out hiking.

What do I miss not having a smart phone? I don't have games at my fingertips. No big deal, I've never been too keen on computer games. I don't have a super-small screen that I can read an e-book on. No big deal, I carry a normal-sized book when I want to read something, and it's much easier to read printed text on a page. I can't keep in touch with my email. I'm not so important that being away from email for 20 minutes is a death-knell. I can't update my social media pages. Why would I want to do that on a small keyboard and screen? I can't have easy text conversations -- this is the only downside, and only because it seems most people these days spent lots of time doing that. But, instead, I can actually TALK to people (because my phone is, you know, a *phone*) that has a much higher communication bandwidth, and eliminates all of the tonal ambiguity of texting / emailing. Manufacturers can't market to me based on my instantaneous location. That's a plus. The authorities can't trace my precise travels over every waking moment. Also a plus. I need to be able to read, digest, and understand directions when driving rather than having a crutch tell me when to turn. All-told a plus, since it hones my ability to navigate by dead reckoning.

Did I forget something?

Oh, yes, I can't take decent quality photos. That's a downside. So when I know I want to take photos, I carry a camera that beats the pants off any cell phone (especially in low light), and deal with the low-quality snapshots that my feature phone takes when I forget.

Comment Re:Circumstantial much (Score 1) 342

Yes, now that I, too, read TFA, I see that. It appears that the fellow's biggest mistakes are (a) talking to other people about rootkits, and (b) buying the lottery ticket himself (or at least not wearing a disguise). Perhaps he should also have waited more than just a month to buy the ticket after rooting the machine. If he was really smart, then he might have started buying smaller wins, and became overconfident and greedy, but that's pure speculation.

Comment Re:Not a surprise (Score 1) 250

It's the nature of the legal system in it's bend over backwards to protect the rights of criminals and assuring that their due process rights are protected.

And yet each of the multiple requests to move the trial to a less blatantly biased location were denied. The poor fellow might be guilty as hell, but the cards were still stacked against him. Personally, I'd like to see the judge disbarred and the verdict vacated. Even the appellate court told the judge to get with the program and move the trial.

Putting aside Tsarnaev's culpability, this trial was as bad as those we rail against in banana republics and oppressive regimes with high and mighty tones. It was purely a political show, and therefore, an insult to justice.

Comment Re:And yet, no one understands Git. (Score 2) 203

The team I was on was using cvs for a long time (quite successfully) and then switched to git. I could never use git without having a page of cheat-sheet notes in front of me. There were some good things about it, some really good things (the code merger was magic), but you had to stay on top of the state of your code in a way that CVS never required.

Comment Re:We aready have this (Score 1) 33

Lots of flux is important. We found that using just gobs and gobs of it, made for really pretty easy soldering that avoided solder bridges and reliably gave us beautiful connections. And by gobs and gobs, I mean enough that the leads are submersed. Naturally, that much of it needs to be cleaned up afterwards, but some alcohol and a toothbrush works well. I worry a little about the flux that gets trapped under each IC, though.

However, when we, on occasion, needed to remove some components, especially ICs, we discovered that there was absolutely no molten solder incursion under the leads. We're using gold-plated boards from OSH Park, so it's easy to see where the solder has flowed and where it hasn't. I suppose if we were even more serious about prototype manufacturing, we'd get some solder paste to lay down first, but we haven't made it to that level of sophistication, yet.

Comment Re:We aready have this (Score 2) 33

Given today's bent towards surface mount, which comes with a whole new garage full of expensive equipment to really do the right way, it is just better to send your boards out to a third party to be etched, drilled, stuffed and soldered.

We've been doing some prototyping in my lab. I've been trained on old-school point-to-point prototypes. They work very well, are usually pretty good models for actual performance, and when its all said and done, take just about as much time as anything else.

My employee, a younger fellow, built a prototype with a breadboard. Egad, I remember those from undergraduate years, and how much I hated them. I spent more time debugging that mess of wires than it would have taken to build it point-to-point from the start.

Except that now everything is surface mount. We were getting ready to buy a rework station. And build one of those hotplate / toaster oven processing things. Then, I found a couple of videos showing people soldering SMT devices with a hand-held iron just fine thankyouverymuch. And, you know, it works great. The key is a steady hand (which I have, even though my assistant does not) and -- critically -- a stereo microscope. Assembling boards can be done pretty fast. In ways, it's faster than through-hole, and heaps less frustrating 'cause you don't need to keep flipping the board back and forth all the time.

The best part is that it's become ridiculously inexpensive to get PCBs made of medium size, with free (as in beer), or nearly free, tools that are really pretty good (and I've used the $25K/seat stuff, too). I've got three full-custom PCBs in front of me that, other than the ECOs from being prototypes, are professional grade. While they weren't free, they were affordable, and much more so than, say, 10 years ago.

So who needs one of these print-you-own circuits? Not me. Or a setup to etch boards myself? No thank you, I'll stay clear of those chemicals. I'm much happier spending a little more to have my boards come back perfect, with real vias, and even four layers if I want! But a garage full of specialized equipment? Nope. Just the old bench, iron, solder, wick, flux, with the addition of a microscope.

Comment Re:SpaceShipTwo (Score 1) 447

An interesting note is that we do have cockpit video of the SpaceShipTwo disaster because no such union was involved, and it did seem to result in useful information. Still not sure which side of the issue I land on. I know I wouldn't want to be videotaped 24/7 at work.

I bet your work doesn't involve being responsible for the lives of hundreds of people.

Comment Re:Non-linear gravity (Score 1) 236

We're trying to explain inflation and the motions of stars orbiting galaxies not matching our naive model.... couldn't a non-linear gravity model explain all this without the dark energy/matter hocus pocus?

Gravity is non-linear, or maybe you didn't notice that distance is in the denominator? It's linear in mass but really very non-linear in distance. m1*m2/r^2. Not even remotely linear.

To review: double m1, you get double the force: linear in m1. Double m2, you get double the force: linear in m2. Double r and, WHOA NELLIE you get 1/4 the force: massively (pun intended) non-linear!

Comment Re:No one is forcing anyone to do anything (Score 3, Insightful) 536

Heck, he could, you know, rent an OFFICE to conduct his business from that has connectivity. There are tons and tons of incubator spaces that would be happy to have his business.

I've conducted business from home. It sucks. There are many good reasons to separate work and home.

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