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Why Open Source Matters For Sensitive Email

Michael Woodhams Trust (73 comments)

Sigh. Now somebody is going to bring up Ken Thompson's "Reflections on Trusting Trust" in 3... 2... oops, too late.

about two weeks ago
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Ask Slashdot: Making a 'Wife Friendly' Gaming PC?

Michael Woodhams Re:And... (720 comments)

This whole discussion seems to have turned into an excuse for people to trot out their sex-stereotype preconceptions about the husband and wife's personalities and the nature of their relationship.

about three weeks ago
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Ask Slashdot: Making a 'Wife Friendly' Gaming PC?

Michael Woodhams Re:And... (720 comments)

What if his wife is also a gamer?* What if there is no other suitable room? What if they feel "the living room is the wife's domain" is twaddle? What if using the large screen TV for gaming is important to them?

* disliking a very loud gaming PC is not the same as disliking all gaming PCs.

about three weeks ago
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Ask Slashdot: Making a 'Wife Friendly' Gaming PC?

Michael Woodhams silentpcreview.com (720 comments)

silentpcreview.com is a web site dedicated to quiet and silent computing, with extensive reviews and forums. They have very recently posted a sample build of a quiet gaming PC.

You can take that as a base and adjust according to taste. (For example, I'm more obsessed by quiet and less by frames per second, so my gaming PC has a single GTX760Ti GPU.) If you have questions, take them to the forums.

about three weeks ago
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Scientists Develop "Paint" To Help Cool the Planet

Michael Woodhams Re:Some details from the paper (145 comments)

Emissivity and absorptivity are the same thing. One way to look at this is the time-reversibility of physics on a microscopic scale, another is that something that was really absorptive but not emissive or vice-versa would give you a really easy way to beat the 2nd law of thermodynamics. Emissivity can, however, vary with wavelength, which is the trick here.

about three weeks ago
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Scientists Develop "Paint" To Help Cool the Planet

Michael Woodhams Re:Some details from the paper (145 comments)

I think the second photograph in the article is the researchers reflected in their piece of film, so the answer is it is reflective like a mirror. I imagine you could put some translucent layer over it at the cost of some efficiency.

about three weeks ago
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Scientists Develop "Paint" To Help Cool the Planet

Michael Woodhams Re:Some details from the paper (145 comments)

Not really - the 40Wm^2 of cooling is only useful if it is in contact with something that can move that cold to where it is needed. (Hand-wavy explanation, really we are shifting heat to the film.) It also needs to see mostly sky, which windows usually don't.
You'd put it on your roof and run water behind it to shift the heat around.

about three weeks ago
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Scientists Develop "Paint" To Help Cool the Planet

Michael Woodhams Re:the law (145 comments)

Would you care to be more specific? My explanation is pop-science simplified, but I don't see an error in it.

More detailed explanation:
In the 8-13 micron (wavelength) window, atmospheric transmittance averages about 80% (estimated from a plot in the paper.) So the energy received is about 20% of what you'd get from a black body at atmospheric temperature (plus 80% of what you'd get from space, which is negligible in comparison.) So the brightness temperature at 8-13 microns is lower than ground level atmospheric temperature. How much lower depends on the average temperature of the atmosphere along the line of sight, and where 8-13 microns falls on the black body curve at that temperature (even this is oversimplifying) and I can't be bothered figuring that out. However, if we can reflect/insulate all energy except 8-13 micron radiation, then our thermal equilibrium temperature will be the brightness temperature at 8-13 microns to which we are exposed. This is, as noted, less than atmospheric temperature at ground level.

about three weeks ago
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Scientists Develop "Paint" To Help Cool the Planet

Michael Woodhams Re:the law (145 comments)

It is possible, because the environment is not in thermal equilibrium. In particular, the film 'sees' colder temperatures at some wavelengths than at others.

Did you not think before you posted that just maybe a bunch of scientists publishing in this area and the reviewers for one of the worlds top scientific journals might possibly have a better understanding of thermodynamics than you do?

about three weeks ago
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Scientists Develop "Paint" To Help Cool the Planet

Michael Woodhams Re:Hafnium in short supply? (145 comments)

The (paywalled) research paper states: "The use of HfO2 is, however, not essential, and can be replaced with titanium dioxide (TiO2), which is less expensive."

about three weeks ago
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Scientists Develop "Paint" To Help Cool the Planet

Michael Woodhams Some details from the paper (145 comments)

For those fortunate enough to have institutional access, the research paper is here.

Quickly picking some highlights:
The atmospheric transmission window is between 8 and 13 microns. They achieved 4.9C below ambient in direct sunlight at 850 watts per square metre. Cooling power was 40.1 watts per square metre. Emissivity (equivalently absorptivity) averages about 70% in the 8-13 micron window (estimated from a plot.)

Here's a quick back-of-the-envelope calculation
90% reflective white paint: absorbs 85W/m^2
97% reflective foil: absorbs 25.5W/m^2, an improvement over white paint of ~60W/m^2
This film: emits 40W/m^2, an improvement over simple foil of ~60W/m^2.
So in this scenario, the special film gives twice the benefit compared to just going for something simple and reflective. (The 90% for white paint is guess-work. The 97% for 'foil' is just matching the special film. Perhaps someone can update the calculations with better founded values.)

The summary title is highly misleading.

It is not paint, it is a manufactured film. It cools buildings, not planets. Yes, with enough you could cool the planet, but if you wanted to take that route, it would be much more cost effective to just use aluminium foil and use a marginally larger area of it (or, indeed, white paint.) Back in the real world, the way this invention cools the planet is by reducing electricity demand for air conditioning. (I saw another article about this in which one of the authors makes exactly this point.)

about three weeks ago
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I prefer my turkey ...

Michael Woodhams Re:What's with turkey anyway (189 comments)

My experience is that swans beat geese for evilness and intimidation value. Although they haven't troubled me, geese do have a fowl reputation, so I'll accept they are evil too.

about three weeks ago
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Bitcoin Is Not Anonymous After All

Michael Woodhams Every single transaction is broadcast to the world (115 comments)

And you can absolutely guarantee that the three letter agencies remember every one of them. They can look at who you've made transactions with and usually get a very good idea just from that who you are. I imagine they get more from fronts and hacked/infiltrated organizations. If they need more and you've ever transacted with a commercial entity within their jurisdiction, you are a National Security Letter or local equivalent away from being identified.

This IP address thing is like discovering that the back door is unlocked and open when the front door is secured by a piece of string.

about three weeks ago
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Former HP CEO Carly Fiorina Considering US Presidential Run

Michael Woodhams The minus 10 billion dollar woman (433 comments)

The market capitalization of Hewlett Packard leapt something like 10 billion dollars on the news that she had been fired. That is to say, the stock market values her at negative 10 billion dollars. If she enters the race, how long can it be until someone labels her 'the minus ten billion dollar woman', and how long can she stay in the race with that label?

about three weeks ago
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Ask Slashdot: Why Is the Power Grid So Crummy In So Many Places?

Michael Woodhams Re:In Finland (516 comments)

Wooden houses as opposed to what? I don't think a well built wooden house is at all a problem in an earthquake zone. It is better than brick, probably worse than reinforced concrete or steel, but who builds single dwellings from reinforced concrete or steel?

I'm from New Zealand, where we have quite high earthquake hazard, and an overwhelming majority of our houses are wooden. Fatalities in the Christchurch earthquake were (mostly? entirely?) not due to wooden buildings but to poor quality 1980s high-rise and ~100 year old brick low-rise commercial buildings. People did die in wooden houses, but in the cases I am aware of this was due to boulders or cliffs falling on them, which no reasonable house would withstand, or heavy furniture falling on them, again independent of house construction.

about a month ago
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In a Self-Driving Future, We May Not Even Want To Own Cars

Michael Woodhams Re:I'd love to have a self driving car, but... (454 comments)

Planes are essentially self-driving now, at least runway-to-runway.

No, they are not. That is like saying a company is self-running just because it has an automated production line. Much of the flight is under auto-pilot, but the human pilots are frequently changing the auto-pilot's instructions. There is a lot of training and skill maintaining in being a pilot. They aren't just there to keepen das hander in das pockets und watschen der blinkenlichten.

All take-offs are manual. Nearly all landings are manual. Mostly 'auto land' just takes the plane to just short of the runway, at which point a pilot takes over for the actual touchdown. Full auto land is possible, but with good visibility it is simply less work to manually land than to set up the auto land.

about a month ago
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What Would Have Happened If Philae Were Nuclear Powered?

Michael Woodhams Re:Ignorant Article (523 comments)

It doesn't work like that, it isn't a chemical fuel you can burn or save. The amount of Pu-238 you need is dictated by your peak power demand. How long it lasts is dictated by nuclear physics (the half life of Pu-238.) You have no control over how fast the plutonium is used up.

about a month ago
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What Would Have Happened If Philae Were Nuclear Powered?

Michael Woodhams Heat pollution (523 comments)

You're trying to study a temperature-sensitive environment in its natural state. An RTG produces lots of heat. (They are only about 5% efficient, so they produce twenty times as much heat as electrical power.) The presence of the RTG might perturb or destroy the environment you're there to study. I don't have the detailed knowledge to say if this is the case.

Plus the issues others have raised: mass, scarcity of suitable isotopes, and launching highly radioactive material on top of hundreds of tonnes of potentially explosive fuel is something you'd rather avoid if possible.

about a month ago

Submissions

Michael Woodhams hasn't submitted any stories.

Journals

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In principio erat Verbum.

Michael Woodhams Michael Woodhams writes  |  about 10 months ago

Here.

In the beginning was the word. Biblical, John 1:1. The full verse is
"In principio erat Verbum et Verbum erat apud Deum et Deus erat Verbum. "
"In the beginning was the Word, and the Word was with God, and the Word was God."

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Ceterum censeo Facebook esse delendam.

Michael Woodhams Michael Woodhams writes  |  1 year,25 days

Here.

Clearly derived from "Ceterum censeo Carthaginem esse delendam" which gets its own Wikipedia page.

This raises the question - how should Facebook be declined? My answer - just don't sign up for it.

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quiquid id est, timeo puellas et oscula dantes

Michael Woodhams Michael Woodhams writes  |  more than 2 years ago

Here.

By web search: "Whatever it is, I fear the girls, even when they kiss."

I can't find a source, but presumably a reference to
Vergil, Aeinid II.49
QUIDQUID ID EST, TIMEO DANAOS ET DONA FERENTES.
Whatever it is, I fear the Greeks, even bearing gifts.

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Vos nescitis quicquam...

Michael Woodhams Michael Woodhams writes  |  more than 2 years ago

vos nescitis quicquam, nec cogitatis quia expedit nobis ut unus moriatur homo pro populo et non tota gens pereat here.

Biblical, "You do not realize that it is better for you that one man die for the people than that the whole nation perish." John 11:50 (spoken by an antagonist.)

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Meus subcriptio est nocens Latin quoniam bardus populus reputo is sanus callidus

Michael Woodhams Michael Woodhams writes  |  more than 3 years ago

here.

It seems fractured, but I think
My Latin sig is criminal because I think stupid people are sane and clever.

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Carpe diem quam minimum credula postero.

Michael Woodhams Michael Woodhams writes  |  more than 4 years ago

here
Quote from Horace, the full version of more common "carpe diem".
Seize the day, trusting as little as possible in the next

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Mea navis aericumbens anguillis abundat

Michael Woodhams Michael Woodhams writes  |  more than 6 years ago

http://linux.slashdot.org/comments.pl?sid=564539&cid=23554467

My hovercraft is full of eels (again).

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Corruptissima re publica plurimae leges.

Michael Woodhams Michael Woodhams writes  |  more than 7 years ago

Here.

Translation by Google:
"The more corrupt the state is then the more numerous the laws." -- Tacitus, The Annals of Imperial Rome.

This may be a Libertarian/Conservative catch-phrase.

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Navicula hydraulica plena anguilarum est...

Michael Woodhams Michael Woodhams writes  |  more than 7 years ago

Navicula hydraulica plena anguilarum est. Omnes castelli tuus nostri sunt. Ed elli avea del cul fatto trombetta.

"Navicula hydraulica plena anguilarum est" = "the hovercraft is full of eels".
"Omnes castelli tuus nostri sunt" = "all your base are belong to us".
"Ed elli avea del cul fatto trombetta" = ?
"Words" doesn't recognize enough of this that I suspect it is not Latin.
Confirmed by websearch: It is Dante making a fart joke.

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Minutus cantorum, minutus balorum ...

Michael Woodhams Michael Woodhams writes  |  more than 7 years ago

here
Minutus cantorum, minutus balorum, minutus carborata descendum pantorum

Translation found by google:
"A little song, a little dance, a little seltzer down your pants."

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Sic transit gloria mundi; non cum clamose, sed cum illatino.

Michael Woodhams Michael Woodhams writes  |  more than 8 years ago

here.

The first phrase is famous and googlable.
"Thus passes the glory of the world; not with applause, but with bad Latin."

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Armis Exposcere Pacem.

Michael Woodhams Michael Woodhams writes  |  more than 8 years ago

Two quotes in one .sig here

Translation by Google:
"Armis Exposcere Pacem" = "They demand peace through force of arms." (A similar sentiment to "Ubi solitudinem faciunt, pacem appellant".)

"Scientia non habet inimicum nisp ignorantem" = "Science has no enemies but the ignorant."

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