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Comment I worked on some of this. (Score 5, Informative) 159

Many *MANY* years ago I was working as a software engineer at Philips Research in the early 1980's when they were looking into ISDN systems somewhat like DSL for the UK market - the business of sending anything over twisted pair copper is a nightmare. I wasn't directly working on the electronics (I was doing software) - but I shared an office with people who did...and they had a heck of a time characterizing the wires that their signals had to go down.

As I recall, the problems mostly come where one wire is spliced into another. Much of this infrastructure was put in the 1900's and it's horrible. Sometimes wires are just twisted together and capped, sometimes twisted and taped, sometimes twisted and just left open to the elements, sometimes they are soldered. Sometimes the places where the wires are joined gets wet when it rains. Sometimes the tightness of the twisted wire connection depends on the ambient temperature. The amount of cross-talk between wires is all over the map as different kinds of insulation was used (and much of it has degraded over the years). At the subscriber end, there were all kinds of phones being used - plus ugly stuff like "Party lines" (where two houses share a phone line!) that had been abandoned leaving extra wires in the ground that were still connected to the network.

All of those things affect the ability to get a decent amount of bandwidth down a wire that was never designed to do it. So the electronics has to be smart about the signal being reflected at each splice down the line and causing 'echoes', and designing affordable circuitry to detect and cancel those echoes was a nightmare. The amount of attenuation you'll get is all over the map - everything has to self- adjust and monitor to give it any chance of working.

So, as poor as DSL can be - it's a miracle it works at all over crappy old telephone wires.

    -- Steve

Comment Re:Lost ability? (Score 1) 308

The problem isn't "going to the moon" - the problem is staying there long enough to do something useful while you're there. What was done in the original Moon missions could be done much more efficiently with robots.

The things we need people for is much more long-term - and the Apollo technology couldn't do that.

I don't buy the argument that the moon is a good stepping stone to Mars - the difficulty of creating and maintaining all the infrastructure to manufacture rocket fuel and get it up into lunar orbit (or back to Earth orbit) is way harder than just going to Mars.

Mars has more gravity, a source of CO2 for plants, a sane day length (also for plants), water (probably) just underground rather than in the shadow of the rim of some craters that never see sunlight (which might be kinda hard to work in, don't you think?)

At the very least, I'd want to see a robot crawl across a lunar crater and take a photo of the water ice piled up there before we made any kind of a judgement as to how useful the moon is.

The main reason I see to go there is to collect Helium 4 for fusion reactors...and then the water would be a bonus. That's a commercial opportunity that a big company could actually go and exploit.

Comment Re: /. editors know less science than mad scientis (Score 1) 223

I agree that the 2nd law is pretty much a statement about statistics - and the 1st law is just a restatement of the conservation laws.

The issue of whether the 1st law might be incorrect is interesting.

Obviously, science knows of no situations where mass/energy is not conserved - and discovering such a situation would be a truly monumental discovery...perhaps more important than things like relativity.

What this means for the perpetual motion nuts is more nuanced.

Firstly, the realms of physics which are attainable by amateur tinkerers are very well explored indeed - there is simply no possibility that some fiendishly clever arrangement of mechanical parts, magnets, coils, hydrogen flames, water electrolysis and so forth is going to break the most fundamental law of physics we know of. All of the science involved in those systems are far too deeply explored and well-understood for that.

If a perpetual motion machine (or anything else that breaks the 1st law) is possible - it's going to be far outside the realms of normal existence - something in the quantum range - or involving black holes and singularities of other kinds - gravity waves, dark matter/energy - things that AREN'T well-understood yet. Sadly, these are things that lie outside the range of amateur tinkerers.

It's possible to overturn major scientific laws - as Einstein did to Newton's laws of motion. But (as with Einstein) - you have to do that outside the realms that have already been tested. When Einstein proposed relativity - we did not have the ability to send super-precise clocks out into orbit to measure how they fared in reduced gravity and high relative velocities - and the flaws in Newton's laws only show up under those kinds of extreme situation.

If the flaws in Newton's laws were noticeable in the realms that amateur tinkerers could reach - they'd have been overturned a century earlier - but only with advanced technology could we actually prove that Einstein was right.

The same thing happened with conservation-of-energy - every experiment open to a Victorian scientist shows that energy is indeed perfectly conserved. It's only when you have nuclear reactors and exotic radioactive materials that the fact that energy can be interchanged with mass became evident that caused us to have to talk about "the conservation of mass/energy" instead. Again, the experimental evidence to overturn this very old "law" only came about with cutting edge instruments and experiments that the average person could never undertake.

So these tinkerers with magnets and such are really wasting their time. It's probably impossible to make a perpetual motion machine - but if there will EVER be a machine that breaks the 1st law of thermodynamics, it'll have something exceedingly exotic going on inside...and it'll come from the bowels of a research lab - or perhaps a cosmologist's telescope.

Comment Re: /. editors know less science than mad scientis (Score 4, Interesting) 223

OK - so how about http://www.genchem.net/thermo/... or http://www.physlink.com/Educat... or https://www.grc.nasa.gov/www/k...

None of them are talking only about heat engines - they carefully point out that historically, thermodynamics was all about steam engines. But nowadays, it's realized that the laws are far more universal than that.

Not one of them talks about "the triple of volume, pressure and temperature" - that stuff is a tiny, tiny subset of what modern thermodynamics covers. You're still back in the Victorian era of steam engines.

Anyway - I'm done arguing with you. I guess that 99% of other people here agree with me.

Comment Re:I'm one of these guys... (Score 1) 223

Sure, you can build machines that store energy and release it slowly - or store it slowly and release it rapidly - or convert energy from one form to another. But the difference between that and a machine that'll run "perpetually" is more definitely a black and white distinction. The former is merely some kind of clever system - possibly interesting, possibly beautiful, possibly useful. But the latter would shatter the laws of physics and require a radical re-think of everything we think we know about the universe.

The existence of a for-real perpetual motion machine would be astounding - more surprising than the arrival of a starship full of aliens, more surprising than the proof of God. Nobel prize material for sure. The inventor could be an overnight billionaire (well, assuming (s)he could manage to patent the beast - which might be a challenge!) - world energy markets would be in total upheaval.

Coming within 99.999999999999% of making a perpetual motion machine ain't that.

You don't live in a grey area - there is no grey area. It's a very clear, bright-line distinction.

Comment Re: /. editors know less science than mad scientis (Score 2) 223

Hmmm - Wikipedia has an article entitled "Laws of thermodynamics" and it says:

    "First law of thermodynamics: When energy passes, as work, as heat, or with matter,
      into or out from a system, its internal energy changes in accord with the law of
      conservation of energy. Equivalently, perpetual motion machines of the first kind
      are impossible."

    "Second law of thermodynamics: In a natural thermodynamic process, the sum of
      the entropies of the interacting thermodynamic systems increases. Equivalently,
      perpetual motion machines of the second kind are impossible."

It backs up those statements with no less than five scholarly references.

No mention of heat engines there...and an explicit statement that conservation of energy and the first law are equivalent. So, no - you're wrong - it's equally valid to discuss the first law and conservation...but conservation laws don't forbid perpetual motion machines of the second kind (the kind that operate perpetually - but produce no energy output) - so talking about thermodynamics makes a little more sense in this context.

Comment YouTube "science" (Score 1) 223

About a year ago, I watched 100 randomly chosen "Science Demo" videos on YouTube.

80% of them were faked, misleading or failed to demonstrate some kind of wild claim.

Of the remaining 20% about half did a "Oooohhh! Cooooool!" kind of a demo - but didn't say what was going on.

So, honestly - you have about a one in ten chance of learning some actual science by watching YouTube videos - and about an 80% chance of being mislead by idiots. This is even worse odds than watching Fox News!

Comment ...profit. (Score 2) 256

1) Sell all of your bitcoins.
2) Tell everyone that the system has failed - watch confidence disintegrate and the price plummet.
3) Buy back all of your bitcoins.
4) Wait for 1e6 people to point out that you're an idiot, thereby allowing confidence (and the price) to recover.
5) Profit!

Hmmm...eh...there should be a "..." bit in there someplace. Sorry!

Comment LGPL as a middle-ground. (Score 1) 208

Stallman is indeed a fundamentalist. His goals are just fine - but he's about as remote from what a typical software engineer is as it's possible to be. That's OK, he's the idealist - and that lets the rest of us be pragmatists.

GPL is great for complete software packages - emacs, gcc...that kind of thing. But for libraries, it sucks. That's why we have LGPL. Sadly, there is a lot of anti-LGPL rhetoric out there https://www.gnu.org/licenses/w...

I think we need something like that for OpenHardware. The ability to use a piece of OpenHardware design in a closed-hardware ensemble without hiding the open part of the design...putting a BeagleBone inside my (commercial) 3D printer perhaps.

Keep that in mind - while I consider why LGPL is a good thing for *parts* of systems.

I get paid for writing software - I need that money to by food, clothing, housing, transport, etc. When I put something out into the public domain it's because I expect to get a fair trade out of it - I give you my software - some of you give me back bug fixes, improvements, etc. My gift to you is repaid to me - possibly in just a small way - but possibly many, many times over...it's a fair trade for some kinds of software - but not for others.

Yet when I open-source a game (I've actually done this) - I got 300,000 downloads in the first month - a lot of thanks and ego-boosting praise - but almost zero actual tangible benefits in return (one guy - a musician - sent me a new, original music track). But if I open-source a library (and I've done that too, on many occasions), then with only a tenth the number of downloads - for years to come, my library was polished, fixed and improved - for free! That's because users of libraries are software engineers, and they are capable of helping out - players of games are typically not.

I learned my lesson - and I mostly OpenSource library code - or complete applications that programmers are likely use the most - these things give me a return on my work.

With a library, we need to allow the maximum number of people to use it in order to get constructive input. If I use GPL, it effectively causes all users of my library to have to license their application via GPL (or similar) too. That cuts out 100% of all commercial users and a large chunk of potential OpenSource users. The only people who can use my code are those who are working on GPL'ed applications - and those are a small minority. With LGPL, I can force the library sources to remain free - while allowing the maximum possible number of users to want to help with the maintenance. This gives me my best return on investment.

So it makes sense to have an LGPL-like license for hardware components - the BeagleBone inside my 3D printer design, for example. Keep the BeagleBone "open" and "free" while allowing me to use it in some larger project that I can sell to keep the lights on.

But for Stallman, this is a religious matter - he's trying to get me to use GPL on my library in an effort to leverage more GPL'ed applications out there. That's a nice goal - but it not one that a typical working programmer can rationally cope with. Closed source code pays the rent.

    -- Steve

Comment Re:It eould be nice, but... (Score 1) 208

The big problem is security. There are too many places for exploitable bugs, deliberate back doors, key loggers, side channels and other forms of pwnware to hide in modern processors. Do you know where all the components in your PC were fabricated?

That's "security by obscurity" - which is no security at all. If you want to avoid all of those exploits, you have to allow the good guys to find, report and fix them before the bad guys find, hide and exploit them.

Comment Re:Wrong... (Score 4, Insightful) 208

What is being discussed is not "free" (as in "free-beer!") chunks of physical hardware, Indeed, that would be tough to do because physical objects are made of atoms - and atoms are not generally zero cost items - so they cannot be copied and distributed for free. We're talking about "free" (as in freedom) hardware that can be understood for $0 and (at some cost/difficulty) copied. The design of the hardware is free (as in beer and as in freedom) but the hardware itself is only free as in freedom.

To look at it another way - if I design and build a house - I can offer the plans for free under a GPL-like license. You can then look at my plane, improve them and you can use the plans to build yourself a house - all without without paying me a cent...but you still have to buy the bricks and pay the builder. You *do* have to pay for your own "copying". That's actually the same with software - if I want a copy of emacs, even though it's GPL'ed, I have to pay for the bandwidth and disk space to make myself a copy of it (the GPL even allows the author to charge me a reasonable amount for making that copy - which is something that almost never happens!) The distinction between copying GPL'ed emacs and copying my GPL'ed house is in the cost of copying the item (fractions of a penny versus hundreds of thousands of dollars). That's not a conceptual difference - it's just a matter of scale - and it's not even necessarily larger. I've downloaded hundreds of Gigabytes of stuff that cost me many dollars worth of disk space to store - and I've downloaded the open-hardware design for a bracket for my "lasersaur" laser cutter that cost pennies to manufacture.

The problem we're discussing with hardware that depends on "binary blobs" is in no way different from writing software that requires an external library for which you don't have source code.

The issue is whether the software library is free (as in beer) or not. If you have to link some GPL'ed program to DirectX in order to run it under Windows - the software can still usefully be GPL'ed because even though DirectX is a closed source "binary blob" - people who run Windows all have a copy of it already. So it's effectively free-as-in-beer. However, if you write your own closed-source middle-ware package and charge people $100 to license it - then creating some GPL'ed application that requires that middle-ware isn't a very constructive thing to do. Of course we'd prefer that all of the libraries we use are also GPL'ed - but that's not an absolute requirement - and it's not a particularly reasonable one out here in the "real world".

OpenHardware that requires use of a binary blob is no different from software that requires some complicated library. If the binary blob is legally copyable (free as in beer) - we can still usefully make our own copy of the hardware. But if the binary blob is either not legally copyable or requires a license fee to copy - then we're in the same situation we were in with software that needs a pay-to-license middleware library.

Viewed in this way, OpenHardware is no different at all from OpenSoftware - EXCEPT that the cost of copying it is higher because it's made of atoms instead of bits.

Comment I wish it was...therefore it is. (Score 1) 311

I don't know what the formal term is but "I wish it was...therefore it is." seems to be a common one these days. It's like "Fixing global warming is going to be a real pain - and I wish we didn't have to - so despite mountains of evidence, I'm going to assume that it's all nonsense." - I see this all over the place.

I blame all of those parents and the media telling kids Disneyesque messages like "If you can dream it, it will come true!" (complete bullshit) - or "You can do or be anything if you want it enough!" (utter nonsense).

    -- Steve

Comment Response menu: (Score 4, Funny) 228

How would you like to respond to this request for information:

[1] Provide information
[2] Deny information

Congratulations! You've decided to "Deny information".

What kind of form letter would you like to respond with:

[1] Military secret
[2] Medical privacy
[3] Area 51-related incident
[4] The dog ate our report
[5] Major government coverup of unspecified nature

Do you wish to include additional information?

[1] No
[2] Yes

Please enter additional information:


Ready to send?

[1] No
[2] Yes

Comment Based on what criteria? (Score 1) 358

This is *soooo* bogus!

According to TFA: "The ratings are based on the number of skilled engineers world-wide, courses and third party vendors."

So - it's NOT based on the number of lines of code written in the last year, or the number of lines of code currently present in actively maintained projects, or the number of programmers (programmer != "skilled engineer") using it, or the number of programmers who are using it by choice rather than reluctantly due to external pressures, or the number who are using it who would much prefer to be using something else.

I find it very, very hard to believe that there are more Java programmers than JavaScript programmers out there - I would be extremely suprised to find any working Java programmers who don't also use JavaScript. I'd be very surprised if there were more Java lines-of-code or Java programs out there than JavaScript. Just about every website out there has some JavaScript code in it - and the web designers use it who do not self-identify as "skilled (software) engineers' - do those people not count in this popularity contest?

Why are we calculating "number of ... third party vendors". Just because there are a lot of junk libraries out there that you need to pay money for doesn't make a language more popular than one with a bunch of open-sourced libraries - or one that has one truly spectacularly good library that everyone uses.

A very popular programming language might well be one that so easy to pick up that nobody much needs to run courses on it, which doesn't need third party libraries and such - and which lots of informal non-engineers use. This claim would entirely miss an insanely popular language that met those criteria.

There are some incredibly unpopular things out there which everyone none-the-less uses because they have little choice (PHP, for example!).

A large number of those Java courses must be "Comp Sci 101" in high schools and further education that are required courses for something else (one of my kids recently did one as a required part of her pharmacy degree - and it was *total* junk). Most of the people who attend them have never seen another programming language and so can't have formed an opinion as to whether they prefer Java - and 99% of those people will never write another program in their lives. Those shouldn't reasonably count in a popularity contest.

How do you count "skilled engineers"? People with some kind of formal accreditation? I've been working as a programmer for over 40 years - and I don't think I've ever worked with someone with a formal language accreditation.

How did they score a "skilled engineer" versus a "course" versus a "3rd party vendor"? Do you score 1 point for a programmer, 10 for a course and 100 for a vendor? Is it 10 points for a programmer, 1 point for a course and 3,14159 points for a vendor? I'm quite sure that tweaking those numbers changes the outcome drastically.

So I simply don't buy the criteria this study used. I don't know how you could know what's "most popular" - because the terms are so incredibly vague.

This is junk science...disregard it.

    -- Steve

Comment Re:Not always a good idea (Score 2) 543

OK - you can't have it both ways! If you think the H1B guys are good enough to come here and take your jobs - then they are good enough to do the same job in whichever other country will physically house them. If it turns out that those guys are best able to do the job - then you can either pay them to come here and do it (and thereby claim their taxes and have them spend their earnings in the US economy) - or you can pay them to work someplace cheaper and spend all of their earnings and pay all of their taxes over there.

If you want less overseas workers doing your work - then you have to either get better at it - or get paid less. It's a market economy and with the Internet, you can't force tech jobs to stay in a particular physical location by passing laws that only operate in other physical locations.

So - better education or lower wages...you choose.

    -- Steve

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