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Comment: Re:Jane/Lonny Eachus goes Sky Dragon Slayer (Score 1) 171

by Jane Q. Public (#47974011) Attached to: 3 Short Walking Breaks Can Reverse Harm From 3 Hours of Sitting

I never said Jane objected to a term for "electrical power". I said Jane repeatedly [slashdot.org] objects [slashdot.org] to including a term for radiation from the chamber walls in his calculation of required electrical power. And Jane continues to do this:

Apparently you did not read what I wrote:

NO!!! This is just plain bullshit. I do NOT object to a term for electrical power. I simply asserted a physical truth: in our isolated system, the electrical power to the heat source, called for by Spencer, has zero dependency on the chamber walls.

What I object to is your insane insistence that the electrical power to the heat source requires a term for the chamber walls. This is sheer nonsense. Standard, textbook physics says the thermodynamic temperature of the heat source, since it is "the hottest thing in the room", as it were, is independent of radiation from the chamber walls. Since it cannot absorb net radiative power from the chamber walls, any electrical power calculation is similarly independent.

You are attempting to add a term to "account for" radiation from the cooler chamber walls, but no such accounting is necessary according to the Stefan-Boltzmann radiation law. No net radiative power from the chamber walls is absorbed by the heat source. The chamber wall do not somehow magically cause it to output either less or more radiative power, therefore the input power is not dependent on the chamber walls. QED. I've explained this (truly) about 10 times now.

Ranting about imaginary violations of the Stefan-Boltzmann law won't help Jane understand physics. It might help Jane to draw a boundary around the heat source and think carefully about exactly why Jane keeps ignoring the heat radiated in from the chamber wells. Accounting for that radiation doesn't "violate the Stefan-Boltzmann law" but ignoring it violates conservation of energy.

There is nothing imaginary about it. I am the one who told YOU to draw your boundary around your heat source. According to the Stefan-Boltzmann radiation law, no NET RADIATIVE POWER is absorbed by the heat source from the chamber walls, and the chamber walls do not affect its radiative power out. I capitalized different words this time in a (probably vain) attempt to get you to understand what is being said here. YOU are apparently imagining some kind of magical net energy flow from less thermodynamically energetic to more thermodynamically energetic, which is a violation of the second law of thermodynamics. The chamber walls neither transfer any of their net radiative power to the heat source, nor do they cause the net radiative power of the heat source to be any less. They have NO EFFECT. Net energy flows only FROM the heat source to the walls, and the temperature of the walls effects heat transfer only, not radiative power of the heat source.

For about 100 times now, I do not claim "no radiation" is absorbed. Just no net radiative power.

Jane/Lonny Eachus can capitalize "NET" all he wants, but it doesn't change the fact that Jane's equation assumes warmer objects absorb no radiation from colder objects. Here's an equation which only says there's no NET radiative power input from cooler objects:

electrical power per square meter = (s)*(e)*(Ta^4 - Tb^4)

The above equation satisfies conservation of energy and says there's no NET radiative power input from cooler objects.

Right. Exactly. That's the Stefan-Boltzmann radiation law, as I've stated many, many times now. Note that it is an equation for heat transfer.

But Jane's equation is different:

electrical power per square meter = (s)*(e)*Ta^4

YES!!! This is a different equation! It's not an equation for heat transfer! It's the Stefan-Botlzmann RELATION between radiative power out and temperature for gray bodies. It is used for calculating RADIATIVE POWER OUT versus TEMPERATURE and vice versa. It is not for heat transfer and I'm not using it for heat transfer. YOU are the one who is getting them confused, not me. This other equation shows that radiative power is dependent ONLY on emissivity and temperature. It does not depend on other bodies. For the third time (today): it's a temperature vs. power equation, not a heat transfer equation.

Further, "electrical" is your own addition. The equation is for power. It doesn't specify "electrical".

That happens automatically. Jane's equation violates conservation of energy by completely ignoring the term describing radiative "power in" from the chamber walls. So Jane's equation says warmer objects absorb no radiation from colder objects.

"Jane's equation" is the textbook equation for calculating temperature from radiative power of a gray body, and vice versa. It is not an equation for heat transfer and therefore doesn't have to account for the chamber walls. At steady-state, it is independent of other bodies. Period. Look it the hell up.

But Jane's equation is nonsense, because absorption is controlled by absorptivity. So we could only ignore the power radiated from the chamber walls if the source's absorptivity = 0. But then its emissivity = 0, so it also couldn't emit any radiation, so it couldn't be a heat source.

RIGHT HERE is where you contradict yourself. You cite the S-B radiation law, above, saying no NET radiative power is absorbed by the warmer body. Apparently you don't understand the concept of NET, even though you have derided me for supposedly "ignoring" it.

I do not claim no radiation is absorbed. I claimed no NET RADIATIVE POWER is absorbed. Those are not the same things. The effect is as if all incident radiation from cooler bodies is reflected, scattered, or transmitted. But since these are diffuse gray bodies of significant mass, they don't transmit. So draw your precious boundary around the heat source. All incoming radiation from the chamber walls is reflected or scattered and goes right back out, so you have no net power IN through your boundary. This is at least the second time I have explained this in detail.

There is no magical flow of NET power into your heat source from the chamber walls. That would violate the second law of thermodynamics. Therefore I do not need to account for radiation from the chamber walls in calculating the temperature of the heat source. That is nothing but imaginary nonsense on your part. The Stefan-Boltzmann RELATION (not radiation law) for gray bodies has only 2 variables: emissivity and temperature.

And that is why, when calculating power needs, I use the appropriate equation for temperature versus power, not the one for heat transfer.

This is textbook stuff, and you just aren't getting it straight. Are you sure you're a physicist?

But Jane's equation is nonsense, because absorption is controlled by absorptivity. So we could only ignore the power radiated from the chamber walls if the source's absorptivity = 0. But then its emissivity = 0, so it also couldn't emit any radiation, so it couldn't be a heat source.

Look at your S-B equation above. What does it say? No net radiative power is absorbed by warmer bodies from cooler bodies. You said so yourself. But NOW, you're claiming that it is. You contradict yourself.

I will repeat: I did not and do not claim that no radiation is absorbed. Just no net radiative power. Any that does get absorbed is just re-transmitted, with a total power (and therefore heat transfer) effect of ZERO. That's why it is not necessary to account for cooler bodies in the temperature versus power out equation.

Jane/Lonny Eachus can capitalize "NET" all he wants, but it doesn't change this fact. Unless Jane/Lonny Eachus would like to correct his equation for required electrical heating power and derive an answer other than 82 W/m^2?

The second equation you cited above is the STANDARD equation for calculating radiative power out of a gray body. I showed you where it was in Wikipedia. It also just happens to be in my heat transfer textbooks. The answer is 82.12 W/m^2. It is the textbook answer. It isn't going to change. Why don't you look it up in a textbook and discover that for yourself?

The first equation you cite, and claim to be using, is an equation for heat transfer between two bodies. It is not the equation for radiant power output of a single body. It is the wrong equation for this calculation.

I repeat: if you truly don't understand this, due to your "greenhouse gas religion" or something, that's just too bad. I'm using textbook physics for situations like this. You are not. You are espousing magical net power transfer from cold to hot, rather than actual physics.

Radiative power out of the warmer body is dependent ONLY on emissivity and thermodynamic temperature. Anything else violates the second law of thermodynamics. It isn't controlled or mitigated by nearby cooler bodies. All else being equal, energy doesn't spontaneously travel from cooler to warmer. That's complete bullshit. Doesn't happen.

Knock off the fantasy physics and pick up a textbook.

Comment: Re:This has been discussed for so long... (Score 1) 197

by MightyMartian (#47971359) Attached to: Outlining Thin Linux

I have six or seven Debian servers, none of which have GUIs, let alone music players. Now it is true that a few servers do have audio capabilities on the motherboards, so an audio driver is being loaded. If I want so squeeze a bit more RAM out of the machines, I could disable those modules, but other than that they are very minimal installs. Basic userland, Samba, maybe LAMP and a few other useful tools and that's about it. I don't know how much smaller you can get without moving to embedded variants like DD-WRT, which have only a subset of a typical *nix user land. Far less useful as servers, mind you.

Comment: Re:Jane/Lonny Eachus goes Sky Dragon Slayer (Score 1) 171

by Jane Q. Public (#47970839) Attached to: 3 Short Walking Breaks Can Reverse Harm From 3 Hours of Sitting

Ironically, Jane's still insisting that warmer objects absorb no radiation from colder objects. Otherwise Jane wouldn't repeatedly [slashdot.org] object [slashdot.org] to including a term for radiation from the chamber walls in his calculation of required electrical power.

NO!!! This is just plain bullshit. I do NOT object to a term for electrical power. I simply asserted a physical truth: in our isolated system, the electrical power to the heat source, called for by Spencer, has zero dependency on the chamber walls.

It is this nonsense dependency on the chamber walls that I have disputed, nothing else. That is a violation of the Stefan-Boltzmann law.

So just to be clear: I don't object to a term for "electrical power" and never have. My only objection is your insistence that the power input to the heat source is somehow related to radiation from the chamber walls. If these are treated as gray bodies: just no. That's a violation of Stefan-Boltzmann.

You are VERY good at trying to make it appear I have been saying things I actually haven't. But it isn't going to fly. It's just bullshit.

Ironically, Jane's still insisting that warmer objects absorb no radiation from colder objects. Otherwise Jane wouldn't repeatedly object to including a term for radiation from the chamber walls in his calculation of required electrical power. Since Jane doesn't even include that term, Jane's assuming that warmer objects absorb no radiation from colder objects.

NO!!! Repeat, for about the 100th time now: no NET radiative power input from cooler objects. That is ALL I have claimed, and it's a direct result of the Stefan-Botlzmann radiation law. Why do you keep disputing textbook physics laws?

Stop lying. Because that's all you're doing now.

Comment: Re:MAD (Score 1) 288

by MightyMartian (#47970799) Attached to: US Revamping Its Nuclear Arsenal

MAD prevented WWIII. I don't care whether the people who build them or the people who authorize their construction are corrupt, or worship a giant statue of a sexually aroused Beelzebub, the fact is that we are kept largely secure from would be Napoleons, Hitlers and Stalins by the mere fact that these weapons exist.

Comment: Re:Yes, just like that. (Score 1, Flamebait) 197

by MightyMartian (#47970679) Attached to: Outlining Thin Linux

Who said anything about open source? Even the old direct Unix server variants all ran Bourne shell or c shell and their descendants. For chrissakes, a CLI-based server OS running a scriptable shell is decades old, predating Windows and FOSS by decades. This idea that Server 2012 is doing anything unique boggles the mind of anyone with even a basic understanding of operating system development and administration for the last half century. Maybe the Microsoft-funded diploma mills churn out admins who actually believe that Server 2012 is some revolutionary step, but for those of us who have been in the industry for oh, over seven or eight years, seeing somebody claim "we tossed out *nix and put in Server 2012 'cause it wuns with just a CLI" is liking seeing some fuckwit claim "I just invented the toothbrush!"

If you threw out *nix servers because you like the modern Windows toolset, then great! No prob. I have a network that runs a Server 2012 AD domain and a couple of Hyper-V servers, so it's not like I'm allergic to Windows. But fuck man, reading the parent's post (I dunno, maybe it's your post, I can understand why you would go AC to write such an incredible retarded post), with the underlying notion that Server 2012 is doing something revolutionary, and yeah, I start seeing red. Server 2012 is merely Microsoft, after twenty fucking years, getting the fucking hint.

Comment: Re:Yes, just like that. (Score 4, Insightful) 197

by MightyMartian (#47970629) Attached to: Outlining Thin Linux

Windows sysadmins amaze. For fifteen years I listened to them rattle on about how the GUI in Windows NT and its descendants was absolutely necessary, that it opened up servers to people who couldn't or wouldn't learn how to work from a CLI. So a few server distros put the head on their installs, worked like mad dogs to build GUI and web-based management systems like Webmin, and now suddenly all those Windows sysadmin flunkies are declaring Server 2012 is the bestest ever because you can run in headless with a CLI.

Listen you fucking asshole. *nix has been running CLI longer than most people posting here have been alive. It had mature toolsets and script libraries when Windows was a 16-bit cooperative multitasking layer on top of fucking MS-fucking-DOS. Generations of system administrators have lived and fucking died while Windows was forcing a clunky GUI toolset that you couldn't fucking script properly, and that you ended up having to go to REGEDIT and a bazillion GPO entries to fine tune.

Oh no, but Windows is so fucking cutting edge because in the last seven or eight years has developed a fucking shell that you can properly fucking script (even if the scripting language in question is a verbose and unbelievably slow executing piece of shit that is in almost every way the exact opposite of the elegance of *nix).

Well congrat-u-fuck-ulations Mr. "We paid a bazillion dollars to Redmond in licensing fees so we could have a scriptable CLI-based OS in our data center". I bet you even think you did an amazing thing.

Fucking Windows admins. Arrogance, stupidity and a total lack of knowledge of their own fucking operating systems incredibly dubious history as a Server OS.

Meanwhile, in the time it takes you to type out the name of a Powershell scriptlet and its arguments to import a CSV and puke it out as a SQL script, I can do write the code in awk or Perl in a bash wrapper. But hey, I must be stupid and you must the be the super fucking genius.

Comment: Re:min install (Score 2) 197

by MightyMartian (#47970583) Attached to: Outlining Thin Linux

If you want a real thin install, pick something like Gentoo and Slackware. You can build minimal installs from the kernel up. In ye olden days when I was working on pretty minimal hardware (low RAM, slow CPUs, small drives), I used to install minimum base on top of a very small kernel (only the hardware found on the machine, plus a few generic IDE drivers just in case I had to move the HD and fire it up on another computer). It's a pain in the rear, and with even low-end hardware having huge amounts of RAM and storage space, I don't bother.

The whole point of the net install version of Debian is that it installs a very base version of Linux; and then you build on top of it. If you really need some sort of unique kernel variant, most fine tuning can be done in /boot or /proc.

I'll be blunt, if you claim to be a sysadmin who works with Linux, and you don't know how to build an optimized small footprint server, then you're talking bullshit, and whoever has hired or contracted you should give you the boot really fast.

Comment: Re:Your employer (Score 2) 171

by Just Some Guy (#47965635) Attached to: Ask Slashdot: Who Should Pay Costs To Attend Conferences?

You're going to the wrong conferences and for the wrong reasons. I go to a pretty well known one each year that I can and my employer gets huge returns on it. The value isn't from going to the training seminars - honestly, I know more about the subject than most of the presenters. The huge win is in identifying ecosystem trends ("oh, I guess we've collectively decided to follow this path now") and rubbing elbows with peers from other companies ("we had that problem, too, and this is how we solved it").

Conferences are probably inefficient at training, but that's not really what you'd want to attend one.

Comment: Re:A few hundred extrasolar planets (Score 1) 80

I see, so you're dislike of a theory somehow should be fed into whether that theory is legitimate or not.

Every piece of evidence gathered over the last century shows the universe is expanding, and that it was once much hotter and denser. The evidence for Big Bang cosmology and inflation are overwhelming, whether that pleases you or not.

If you aren't rich you should always look useful. -- Louis-Ferdinand Celine

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