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User: cwsumner

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  1. Re:It needs a killer app. on Why MakerBot Didn't Kickstart A 3D Printing Revolution (backchannel.com) · · Score: 1

    And the killer app would be shoes. Imagine being able to print custom running shoes exactly to the size/shape of your foot.

    Or at least be able to print foamy insoles and have that new shoe feeling every month.

    That's an excellent idea. It is something that would maybe justify the machine.

    Microcomputers, and computers in wide use, were launched by the first "killer app", computerized spreadsheets. Supercalc, Visicalc, long before microsoft had anything but Basic. All the ideas before that were like the current ideas for 3D Printers, mostly toys.

    The term "Killer app" was first used by the people trying to make the next big launch, after that. But it was not so easy.

  2. Leading edge on Why MakerBot Didn't Kickstart A 3D Printing Revolution (backchannel.com) · · Score: 1

    There is a reason that the leading edge of technology is called the "Bleeding Edge".

  3. Re:!Revolution on Why MakerBot Didn't Kickstart A 3D Printing Revolution (backchannel.com) · · Score: 1

    Um, yes he does. Especially computers. Overpriced, feature-poor and unreliable were the hallmarks of some of the first gen microcomputers I used in the late 70s and early 80s. ...

    That was actually second generation (of micro-computers, not mini or mainframe). I had a CP/M computer in 1980 that worked fine and even had disk drives. Eight inches across! 8-)

    What you are describing was 60's and 70's, the Imsai computers were early 70's, as I remember. The first Altair was in mid 60's.

    I had Compuserve Micronet, that was a bit cheaper. The Internet based on HTML was later, though.

    Compuserve still has a website up. I still have a Compuserve email address, but it really goes somewhere else. It's been so long that people don't even ask if it is old anymore! 8-)

  4. Re:I am amazed that there is no current limiter on The 'USB Killer' Has Been Mass Produced -- Available Online For About $50 (arstechnica.com) · · Score: 1

    .... The protection diodes found within the USB host are only designed for ESD-like voltages and currents. They can not handle a high voltage being applied for a long time. ...

    Electrostatic Discharge can be around 20,000 volts. What do you think makes the spark and the "snap" sound?
    But it might be shorter than this thing, it depends on how big the caps are. And how long the devices can endure the overage.

  5. It never ceases to amaze me how different people can be from each other. Something that tastes good to some people tastes awful to others. For you, Splenda "doesn't taste like sugar", yet for me it is the only artificial sweetener I will use because it takes just like sugar (to me). ...

    That's true, even the same person's tastes can change over time, sometimes just a few minutes is enough.

    To me "Splenda" tases like used motor oil and sugar is almost as bad, maybe because I eat so little of it now.

    Artificial sweetners also tend to upset my stomach. It seems to be related to type 2 diabetes. So be careful giving stuff with artificial sweetners to anyone who has that...

  6. ... hmm tasty, any one ready for that ever so tasty chocolate flavoured soylent green bar, ...

    Fixed that for you... 8-}

  7. Re:All you flight software noobies.. on ESA: European Mars Lander Crash Caused By 1-Second Glitch (space.com) · · Score: 1

    ...
    4) Fault handling is tricky - you can easily go down a rat maze of low probability events generating code (and hardware) to handle obscure corner cases, thereby increasing your test costs and time, and potentially introducing other faults. For a lot of plausible error scenarios, it's likely you're going to fail for other reasons, so there's no point in trying to do things like estimate state from other sensors. ...

    That's true, but it can also encourage a habit of lazyness in the designs. And, an exceleration spike when the parachute opens or the landing gear locks, is not something that has low probability. It sounds like a lot of "not my job".

  8. Re:Filter or not on ESA: European Mars Lander Crash Caused By 1-Second Glitch (space.com) · · Score: 1

    When the altitude stops changing for a whole second the filter is going to have to be a long one! And that ain't desirable for responsive control.

    The real question is how could the sensory processor have overloaded in the first place? ...

    ... When I heard about the crash landing I literally said to a friend of mine, "I bet the subroutine that cuts the parachute loose so it doesn't land on top of the payload detected the thump of the parachute strings going-taught, determined that meant it was on the ground, and cut the parachute." ...

    Mechanical devices can have really long "bounce" times, when it includes a parachute and riser lines it can easily be over a second.

    Not only was their mechanical testing lacking, their simulation software should have also picked this up. And they had a similar failure when the landing gear opened, in a previous lander.

    It sounds like they had a lot of scientists, but no engineers!

  9. Re:its a lie on President Obama Says He Can't Pardon Snowden (arstechnica.com) · · Score: 1

    Obama didn't say it's illegal to pardon Snowden, he said he can't. He may well have meant that as in when you ask someone to marry you on the first date and she says "I can't."

    Saying something to a crowd that are of one opinion, that is going to make them angry, when they outnumber your security, is not good tactics!
    Try standing in front of a crowd and saying something like that, likely your own instincts will not let you say it!
    I didn't vote for Obama, but jeeze, cut the guy some slack! 8-)

  10. Re:And Obama once again is a blatant liar on President Obama Says He Can't Pardon Snowden (arstechnica.com) · · Score: 1

    Trump needed news coverage, and not releasing the taxes gave him lots of free news coverage. Like "Hollywood" says, "there is no such thing as bad publicity!"
    And it worked. Bet that when the taxes are finally released, it will turn out there was nothing wrong with them at all? After all, he has some very good accountants. ;-)

  11. I have to wonder if our country, or maybe the world, is under a "divide and conquer" attack. An attack that uses psychological warfare operations, through the news systems and media services (including social media).

    Or maybe it's just the political parties doing it? Nah... they are not smart enough. 8-P

    Am I just kidding? You tell me, I don't know for sure. 8-)
     

  12. Re:If confirmed, does this make it realistic? on Final NASA Eagleworks Paper Confirms Promising EM Drive Results (hacked.com) · · Score: 1

    I have seen half a dozen test descriptions, of different people's tests, over the last several months. Plus those ones on youtube, which are a bit "ad-hoc". One is even talking about a test in orbit "soon", but that one was not NASA.

    A superconducting cavity, or just a gold lined cavity, would probably increase efficiancy by an order of magnitude or more (much more). And since the RF at that frequency does not penitrate the metal very much at all, a thin electroplate might be enough.

    Should be interesting... 8-)

    (Lets just hope that it does not have an "exhaust/side effect" that is the combination of indetectable and harmfull !)

  13. Re:The Unintended Consequences of Bad Math on Snopes.com Editor on Fake News: Social Media Is Not the Problem (backchannel.com) · · Score: 1

    You are, no doubt, familiar with the idea that a minimum sample size is necessary to generalize results to the population?

    Well, what no-one seems to know is that the math works both ways, the results can not reliably be applied to any group -smaller- than the required sample size.

    When you are faced with a single person, statistics cannot tell you -anything at all- about them!
    This mistake is the cause of most racism and prejudice.

  14. One of the biggest lies is that all conservatives are in those group-names, that the left uses to smear their enemies. And you bought it, hook, line and sinker!
    Before you talk about reality, try coming out of your Urbmon Monad... 8-P

  15. Re:Back That Truck Up on Snopes.com Editor on Fake News: Social Media Is Not the Problem (backchannel.com) · · Score: 1

    From what I have seen, the older Snopes editors are more "even handed" in their articles, but the new hires have a noticable left bias. They probably don't even realize it, because most of the people that taught them considered it normal, or at least justified. But read several articles and it becomes noticable.

    So it depends. But anyone can tell when a news service has a problem, because similar subjects from different sources are treated quite differently.

    However, Snopes is not as bad as many others. And as pointed out above, the description of the research is most of the value of the site. When in doubt, skip the conclusion and read the research. (As with any kind of research reports.)

  16. Most people don't. Most people find single opinion and then only look at things that back that opinion up.

    Most people don't do what "most people" do! Don't drink that "coolaid"...

  17. I'm led to understand reality has a pretty strong left wing bias, also.

    No, that's just part of the fake news. It's just that some parts of the left have been doing it longer, and had special training at it.

  18. Sorry, it doesn't work quite -that- good... ;-)

  19. Re:The great hope! on Final NASA Eagleworks Paper Confirms Promising EM Drive Results (hacked.com) · · Score: 1

    That's true. But we had this discussion months ago, and the experiments are still there. And growing...

  20. Re:Numbers in perspective on Final NASA Eagleworks Paper Confirms Promising EM Drive Results (hacked.com) · · Score: 1

    This one is an experimental setup, not a production design. There are already experiments of this that can produce more thrust.

  21. Re:Let's just start testing already on Final NASA Eagleworks Paper Confirms Promising EM Drive Results (hacked.com) · · Score: 1

    Admittedly, this probably isn't breaking physics, we just don't fully understand it. But I think the best way is to may build some small probes, launch them, and see what happens. ...

    Just don't send something like that out of the solar system, if we even -look- like we are launching a "Von Neuman Plague" our neighbors might gang-up and nuke our planet, just in case! 8-{

  22. Re:If confirmed, does this make it realistic? on Final NASA Eagleworks Paper Confirms Promising EM Drive Results (hacked.com) · · Score: 1

    What are you talking about "continue to verify"? There has been no verification _at_ _all_ at this time. Just the same team likely making the same measurement error time and again. That is not "verification".

    Not true, there are several teams and it is far enough that they are arguing about what shape is more efficient. This is just the first to bother to publish in one of the old journals.

    Hell, people on youtube are doing experiments in their apartments. If they are not all hoaxes, they are getting results well above noise level.

  23. Re:Read the Paper on Final NASA Eagleworks Paper Confirms Promising EM Drive Results (hacked.com) · · Score: 1

    ... We recently had an example on how to do this right: The case where some physicists measures FTL particle transmission. What they did was to publish everything, and explain that they did not actually believe this was indeed FTL and asking for help to find the source of the error. That way they remained committed to a proper scientific approach. In the end, this turned out to be a faulty connector, but it was very hard to find that flaw and needed help from a lot of smart people.

    They already did that, and this is one of the experiments trying to find the flaw or error. This has been in process for a number of experiments by several organizations.

  24. Re:If confirmed, does this make it realistic? on Final NASA Eagleworks Paper Confirms Promising EM Drive Results (hacked.com) · · Score: 1

    Agreed.
    It is possible to do a better experiment. With a superconducting cavity, you can get probably 10^6X the circulating power, and (based on their surprising linear slow slope of thurst vs power) a very large thrust.

    This is a moderately expensive experiment (few million $), but would be very definitive. Lots of labs, including mine could do this.

    It's already been done with higher power, check YouTube. It's also about the fourth or fifth expiriment, and one of the recent ones might have used superconducting cavity, but it isn't published yet.

    This experiment was just the one looking for errors and side effects.

  25. Re:If confirmed, does this make it realistic? on Final NASA Eagleworks Paper Confirms Promising EM Drive Results (hacked.com) · · Score: 1

    ... Said EM powered craft shoots off at unexpectedly relativistic speeds.

    Meanwhile, the Earth has stopped rotating on its axis...

    Oops!

    This is an actual concern. After all, Madam Curie died of radiation poisoning. And other reaserchers have suffered side effects of their research.

    Be cautious about doing your own experiments with this stuff. 8-}