Domain: utoronto.ca
Stories and comments across the archive that link to utoronto.ca.
Comments · 412
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Uptime for a Gentoo desktop machine
Here's the uptime for a Gentoo desktop machine.
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Re:At $500,000... How long to pay back the cost?
New solar cells developed with nano-technology at the University of Toronto (http://www.news.utoronto.ca/bin6/050110-832.asp ) convert light from the blue-yellow end of the spectrun down to the near-infrared (current cells work only in the bluie-yellow end of the visible spectrum). This could increase the conversion efficiency by a factor of 5. Additionally, this technology lends itself to be able to literally print the cells on a plastic substrate, significantly lowering manufacturing costs.
Currently, a typical home solar setup produces about 4.5 KW (max) and costs about US $25,000 to install. Payback takes about 20 years. If this new technology could change both numbers by a conservative factor of say, 3, you'd be looking at 13.5 KW (max) systems going for about US $8,500, and payback times of 5 years or so. Then, you'd have something. -
Re:Black hole reproduction
He gave an explanation in there as to why the antimatter was more likely to fall in than the matter; I don't remember the details offhand. A quick search reveals the following interesting sites:
http://www.upscale.utoronto.ca/GeneralInterest/Ha
r rison/BlackHoleThermo/BlackHoleThermo.html (Look in the 'Black Hole Thermodynamics' section)http://www.sciencenews.org/articles/20040925/bob9
. asp This site seems geared more towards the non-techincal reader, but it includes this paragraph, paraphrasing Stephen Hawking, which seems to support my earlier statements:Hawking came to this view when he introduced some of the elements of quantum theory to black hole physics. According to quantum theory, the vacuum of space isn't empty but seethes with pairs of elementary particles winking in and out of existence. One partner in each pair has negative energy, which keeps that particle gravitationally bound to the black hole, while the other has positive energy, which gives it enough oomph to escape from a black hole.
In short, I don't know (I am a computer nerd, not a physicist); I am simply parroting what I have read 8-)
Cheers
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In Memoriam
As a University of Toronto Engineer, I was a member of the UofT Blue Sky Solar Racing Team in 2003 and 2004. In that time, I had a lot of fun and met many great people, one of whom was Andrew Frow, who lost his life in a solar car accident in August of 2004. He was a great leader with a vision, who always kept the big picture in mind. He made every member of the team feel like they were doing something useful, even us F!rosh that didn't know anything about Engineering yet.
Aikon-
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In Memoriam
As a University of Toronto Engineer, I was a member of the UofT Blue Sky Solar Racing Team in 2003 and 2004. In that time, I had a lot of fun and met many great people, one of whom was Andrew Frow, who lost his life in a solar car accident in August of 2004. He was a great leader with a vision, who always kept the big picture in mind. He made every member of the team feel like they were doing something useful, even us F!rosh that didn't know anything about Engineering yet.
Aikon-
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Re:The other side the matterI'm sorry if I overreacted; I'm from New Zealand and the ozone hole is a big deal around here. My memory from school is that because Antarctica (a big freakin' continent), rather than frozen ocean, is at the south pole the winds are stronger, or more stable or something. So although more CFCs were released in the northern hemisphere, most of the mixing between the upper and lower atmospheres happens in Antarctica. I can't find the right query to get google to tell me precisely, but this touches on it:
http://env.chass.utoronto.ca/env200y/know/ozone.ht mlIs it possible that other processes might start to consume ozone, an Arctic ozone hole for example? We don't know. Periodically, large depletions in ozone (more than 10-20%) have been reported from the high northern latitudes. While the processes that lead to this decrease are similar to those at the Antarctic, the pattern has not been similar. The Arctic polar vortex is weaker than the Antarctic one. Stratospheric temperatures at the Arctic are not as low as those at the Antarctic, hence PSC formation is reduced. However, global warming . may strengthen the Arctic polar vortex. We already know that stratospheric temperatures are falling, so it is possible that an Arctic ozone hole could develop in the future. It would likely be smaller and weaker than the Antarctic hole, but could have serious consequences for Canadians.
And to answer your second point:
http://www.aad.gov.au/default.asp?casid=11427Scientists investigating the 2006 ozone hole have used a range of instruments to measure ozone concentrations, including satellites, balloons, and ground-based spectrometers and gas samplers. Measurements showed that the area of the hole was greatest on 24 September, with an area of approximately 29 million square kilometres, more than twice the area of Antarctica.
For those who are interested, Wikipedia tells me that the area of the United States is a tad under 10 million square miles - so the Antarctic ozone hole is three times the size of the US. -
Re:Yet another thing...
Dead serious: Before any new law may be passed, the legal code shall be reviewed in it's entirety and thoroughly checked for existing laws serving the same purpose. If any such law shall exist, the proposed law may not be passed. If multiple laws serving the same purpose are found, they shall be reconciled into one non-self-contradictory law with the eldest law taking precedence. Not only will Congress be too preoccupied by this to do any more damage, but eventually the legal code will become understandable again.
Have you heard of a lawspeaker? Here's a good article:
Rationalizing regulation: In ancient Iceland, the people would gather together in an assembly, the Althing, once each year to hear their corpus of law recited from memory by a professional lawspeaker. If a law was forgotten during the hours-long proclamation and no Icelander objected then it lost its force, limiting the number of rules that could be pronounced before the speaker dropped from exhaustion. Thus, only rules that concerned the people and advanced the public good could remain "on the books".
I'm inclined to agree with you; our laws are the legal equivalent of spaghetti code. They're poorly crafted - too permissive in places, too restrictive in others, too complicated altogether. When most citizens break laws during the course of a normal day, something's wrong with the laws.
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Re:Wait...
You really can't tell the difference between the examples you just gave and the Stella case? That's scary.
Grandparent: I think there's a reasonable expectation that spilled coffee won't cause third-degree burns, requiring third-degree burneight days of hospitalization and two years of treatment.
When you spill a cup of coffee on yourself, your expectation as a logical human being is that you will spend the next few minutes swearing, spend the rest of the day with stained trousers, and spend the rest of the week with a painful red spot on your groin. You therefore treat the cup with some caution, but not too much. You do not believe you are in real danger. If you spill the coffee, you shrug, well aware that you weren't treating it with caution, commence swearing and go on with your life. You do not expect that you will end up with a third-degree burn in five seconds. In case you were unaware of this (and I really think you must be to consider it in any way normal or sane), this is what someone with third-degree burns looks like. I urge you to look. It is not a patch of redness. It will not go away in a few days. No-one in their right mind would believe a cup of coffee could do that to someone.
There is a huge difference between someone making a foolish decision and suffering the consequences they should have expected (redness, irritation, ruined trousers) and someone making a foolish decision and suffering consequences they could not have expected (third-degree burns, skin grafts, medical treatment costing $11,000). Someone who knows they are running the risk of ruined trousers acts very differently to someone who knows they are running the risk of burning their crotch to the point of annihilation. I would cheerfully take a chance on the former (as, I suspect, would you), but never the latter. In other words, Stella was not simply a moron, but a rational person who took a calculated risk and found that the stakes were far, far higher than she had any reason to expect.
If someone takes a risk, and the consequences are not what a reasonable person would expect, and someone is at fault (as MacDonald's was at fault - they'd settled hundreds of cases for burns out of court before, so they knew there was a problem, and the coffee was well over the state-mandated maximum safe temperature), then that someone should pay. Just as if an advertisement informs you that a practice is safe, knowing that it carries a high risk of death, the advertiser is partially at fault if you die due to the practice (e.g. tobacco ads while the health risks of smoking were still under dispute).
Just a note: If MacDonald's had placed warning labels on the cups saying "WARNING: COFFEE MAY CAUSE THIRD-DEGREE BURNS", I would be siding with you. Unfortunately, they said "WARNING: COFFEE IS HOT" or words to that effect, which is simply an obvious truism - not a warning of some abnormal danger. Now, your examples of frivolous lawsuits and why I would be against them:
I think there's a reasonable expectation that car manufacturers should put coffee holders in convenient locations so that I don't decide to place hot coffee between my legs. Blame Ford.
Wrong! If Ford places the coffee holder in an inconvenient location, it's your fault if you decide not to use it. You were under no false impressions as to the risks you were taking - you knew damn well that you might spill the coffee over yourself. Ford just makes shoddy cars. They might be partially to blame if, for example, the coffee holder snapped and poured coffee all over you.
I think there's a reasonable expectation that a cigarette lighter will not set fire to my hair which hangs in my face as I light my cigarette. Blame Bic.
Now that's just bullshit. As you yourself indicate, any reasonable person would think there was a high probability of your hair catching fire. Not the case with the coffee. -
Re:This just in: It's 5 Billion, not a TrillionOur galaxy, the Milky Way Galaxy, is part of a small cluster of about 45 galaxies known as the Local Group. The Milky Way is the second largest galaxy in the Local Group. The largest is M81 (aka Andromeda), and is hurtling toward us at 186 miles/sec, and is going to smash into our galaxy in about 3 trillion years.
Oh the horror.
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Re:What's wrong with that?
"P.S.
/. strips sarcasm tags. For the terminally holier-than-thou set, the above was indeed sarcasm."
HTML entities are your <friend> ;)
http://www.utoronto.ca/webdocs/HTMLdocs/NewHTML/is o_table.html -
Re:Too many syllables!
Funny, I learned this as:
There once was a lady named Bright,
who traveled much faster than light.
She left one day, in a relative way,
and returned on the previous night.
But the original is so:
There was a young lady named Bright
Whose speed was far faster than light;
She set out one day,
In a relative way
And returned on the previous night.
followed by:
To her friends said the Bright one in chatter,
"I have learned something new about matter:
My speed was so great,
Much increased was my weight,
Yet I failed to become any fatter!"
Ah, synoptic limericks! -
Re:Sad Day in the UK
America is seen as a strange, nutty, violent backwater by the rest of the world
"These people are social outcasts whose career or class ambitions haven't been fulfilled," he explains. "They blame their failure on a particular group that they feel is responsible for excluding them from their proper place in society. They begin fantasizing about a campaign of vengeance against the group -- which in a tiny proportion of cases -- ends, tragically, in actual violence."
- Elliott Leyton, -
Re:missing the point?
Actually the technique of using a "parallax screen" on an LCD to get a "3d"/stereogram image was proposed 3 years ago. here we go. In practice it wasn't that great. Also I believe the technique was also independently discovered by an art student a year or two ago. I'm not sure I understand why this is news now...
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Cheating detection program for CompSci (MOSS)
University of Toronto has had a cheating detection program called MOSS running against student program assignments for several years now. How many other schools have something similar?
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It's called antagonistic pleiotropy
It's called antagonistic pleiotropy http://en.wikipedia.org/wiki/Antagonistic_Pleiotr
o py. The fitness curve at it's simplest has a central maximum, and drops off towards the extremes. The location of the maximum will depend on a number of things - for one examination see http://medbiograd.sa.utoronto.ca/pdfs/vol2num1/10. pdf (page down to the start of the article) -
Re:A Species lasts ...While a nice naturalistic point of view, it's not really true. It's a lie that people with agendas push. Animals can, and do in fact "hate" and "kill another member of [their] own species through hatred". In particular, here's a short mention of one incident where one "tribe" of chimpanzees waged war against another "tribe" and exterminating the other tribe:
As late as the early 70s, it still appeared plausible that the "pre-cultural" paradise on earth whose potential existence haunted the European imagination long before the birth of Rousseau manifested itself in its pristine form in the social life of the chimpanzee. It was man, separate from all the animals, who would kill conspecifics, who was insanely aggressive because of the rapid and unpredictable growth of his cortex; because of the pathological effect of his culture; because of his capacity for language (and ideology) and tool-use. But then in the depths of the Combe National Park in Tanzania Figan, Humphrey and their "Kasekala" compatriots moved out of their habitual territory and attacked and mortally wounded Godi, a member of the "Kahama" group. Initially perceived as an aberration, this pattern of behavior soon came to appear common, if not defining. Less than two months after the attack on Godi, De was dispatched, in the same manner then, a year later, Goliath and so on, until all seven of the adult Kahama males (and some of the females) were killed.
From http://www.psych.utoronto.ca/~peterson/primate/chi mps.htm
So, no, humans aren't even exceptional in the capacity for murder. -
Re:Wii only gets 16% marketshare?!?
Everyone that thinks the controller is innovative and is the key to the Wii's success needs to remember (Chances are, they probably weren't even born then) that Nintendo tried this exact same approach nearly 15 years ago with the http://individual.utoronto.ca/roninkengo/pictures
/ powerglove.jpgPowerglove. They even marketed a movie about it ffs. This was the most embarassing device ever released for the NES, followed closely by the Rob the Robot. Seriously, thank G-d that there was still an option to use a brick controller with a 4 way direction pad and two red buttons, it was like a hundred times better than the glove. -
Re:Great, just great...
I hate to break it to you, but that "10k rock" is really worth something like $50 (should free markets actually work in real life). Only thanks to DeBeers' amazing ability to mess with people's heads and wallets, would you, or any otherwise intelligent and reasonable person, go simply gaga and part with 10k for it. But then again the world is full of mass delusions and con-artists willing to make a buck on them. Pet rock anyone?
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Re:Who's regressive?
It's not a troll. Rural India is anything but progressive regarding the equality of women.
http://www.law-lib.utoronto.ca/diana/puneannotatio ns.htm
And the perception that many countries would like to limit Internet access (and uncensored news) to their populace is neither new nor paranoid.
If you hand a MILLION laptops with built in WiFi and mesh networking to children they are going to see a bigger part of the big picture. It will lead to change. Change makes control more difficult. For details ask the RIAA. -
Re:nice
There have been experimental verifications of General Relativity for quite some time now. IIRC, Einstein himself noted how his theory accounted for a slight deviation in Mercury's orbit that Newtonian mechanics could not. And, if you don't consider astronomy quite "experimental" enough, there have been experiments with clocks and other such things. The first Google hit got me this page, which looks like an understandable enough summary.
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GSA's CITA
Contact the GSA's CITA (http://www.gsa.gov/Portal/gsa/ep/contentView.do?
c ontentId=9815&contentType=GSA_OVERVIEW) and let them know what issues you are having. They can probably tell you about some devices you haven't heard about before.
http://www.utoronto.ca/atrc/reference/tech/altmous e.html
http://web.mit.edu/atic/www/tools/mice.html
~Gildas (too lazy to log in) -
It turns out that Netscape was evil, too...
I too loved Netscape back in the days of the war with M$. But back then, I loved it not because it was better than IE, but because it was the best out of about 10 browsers that were competing fairly in the market.
Then, Netscape became evil (in the way that Google wants not to). They had earned their lead in the market, but with it they added non-standard features, making simple HTML viewing too hard for any small company. There are many examples of this. Here's the top one I found from Google:
http://www.utoronto.ca/webdocs/HTMLdocs/NewHTML/ne tscape.html
They embedded a custom scripting language (Javascript), and added hooks for every darned thing you can imagine. They even tried to get M$ to work with them to drive out all the little guys. In short, they used monopolistic practices to drive out the competition. In doing so, they stupidly handed over the whole market to M$.
With Firefox, the evil motives are gone, so it's no wonder that it's catching on. I love it. Rock on Firefox! -
Re:Money transfers?There is no spoon.. uh, Comma Splice.
Solution 4: Use a subordinating conjunction.
Subordinating conjunctions are similar to coordinating conjunctions in that they allow you to indicate the logical relationship between two independent clauses. However, unlike coordinating conjunctions, subordinating conjunctions lay unequal stress on the two parts of the new sentence. We can use the subordinating conjunction although to solve our comma splice problem, and we can do so in two distinct ways
I completed my essay, although I have not submitted it.
Although I completed my essay, I have not submitted it.As the word subordinating suggests, we place less stress on the clause introduced by the subordinating conjunction. In the first example, the fact that I have not submitted the essay appears as an afterthought; in the second example, it is the point.
There are a great many subordinating conjunctions in the English language. Here are a few of the more common ones:
while, although, because, if, since, unless, whether, when, why, as, before, after, if, whether, that, once
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On the same day...
http://www.news.utoronto.ca/bin6/060612-2365.asp
... related? -
Sender is Sent; Receiver is Received
Marshall McLuhan used to say that in electric communications (thinking of telegraph, radio, and television) the sender is sent. The effects of that type of communication was very much different than a book or a letter by post, both of which could also be sent, but sent as a proxy for the author.
With the acceleration due to the instantaneity of Internet-enabled communications, there is a reversal effect (as described in McLuhan's Laws of Media: The new science). With email, the receiver is received. That is, the person who receives the email imposes her/his own context, mood, and emotion to the received email, as if it was received in a face-to-face (i.e., oral-like) communication. It is the effect of the instant (as in f-t-f), but with the asynchonicity of proxy communication (as in book or post). Until one become acclimatized to the apparent incongruity, misinterpretation is bound to happen.
I remember experiencing the exact same effects when fax was new, and when email was new, both in a business context. When a customer became irate with what I thought was a civil fax, I was confused. When it happened again with the initial email some years later, I remembered the fax incident and thought there might be a pattern here. Now that I've spent the past few years studying, working, and consulting in media theory, I understand why it happens.
It's not the content; the medium is the message! -
FUD, misinformed, or true?
"None of the prominent desktop applications that can create and save documents in OpenDocument currently work well with screen readers, magnifiers and other assistive technologies -- at least at a level comparable to that of products from Microsoft, whose 40-person Accessibility Technology Group is now widely praised by disabilities advocates"
I'm curious. I am not disabled but I've noticed many system wide accessibility features in linux in the various installs I've performed and a google of the web shows significant commitment and development to achieve accessibility in linux.
I'd like to hear some specifics on what is wrong with the current state of accessibility in linux and what is wrong with the current commitment.
The current argument is accessibility in ODF capable linux applications. Some of the accessibility projects are designed from the OS level up so I find it hard to believe there is no support in the applications when it is provided by the OS, so what is specifically wrong with what is there?
I also find it interesting that Windows accessibility required "kicking and screaming" to get 40 developers inside a multi-billion dollar corporation and yet the FOSS community appears to have a significant number of accessibility developers and the kicking and screaming just started. Is the whining justified or did Winske get an earful from the local MS rep?
http://larswiki.atrc.utoronto.ca/wiki/LinuxUnixAcc essibilitySoftware#OperatingSystemEnhancements
http://developer.gnome.org/projects/gap/
http://accessibility.kde.org/ -
Linux Adaptability
It's been a while since I've had to look into speech recognition for linux, but this link should help you get started: Linux Accessibility Resource Site
Read down to the section about speech recognition. I hope that helps. -
Re:Blowing Hot Air
Consider the simple fact, drawn from the official temperature records of the Climate Research Unit at the University of East Anglia, that for the years 1998-2005 global average temperature did not increase (there was actually a slight decrease, though not at a rate that differs significantly from zero).
Full story here There IS a problem with global warming... it stopped in 1998.
Well, that position is not without its critics. There is evidence to suggest that the way the data was collected was not adjusted for changes in the technology they used to gather it, and when it was collected -- specifically, how the heat-shielding to rule out the effects of sunlight warming has been improved over time without that being factored into the analysis.
This blog gives a nice summary of what happened, as well as a bunch of relevant links. (The author is an astrophysicist, so he's not without some ability to read science papers and follow the math.)
From this article:Dr Sherwood argues that it is not. In particular, changes in radiosonde design intended to reduce the original problem of over-heating have not always been accommodated by reductions in the correction factors for more recently collected data. Those data have thus been over-corrected, reducing the apparent temperature below the actual temperature.
Dr Sherwood and his colleagues hit on a ruse to test this idea. Because weather stations around the world release their balloons simultaneously, some of the measurements are taken in daylight and some in darkness. By comparing the raw data, the team was able to identify a trend: recorded night-time temperatures in the troposphere (night being the ultimate form of shade) have indeed risen. It is only daytime temperatures that seem to have dropped. Previous work, which has concentrated on average values, failed to highlight this distinction, which seems to have been caused by over-correction of the daytime figures.
In short, since the heat shielding on the measuring devices became more effective, the daytime measurements were skewed downward, while the nighttime readings showed a warming trend.
So if the improved technology skews the data, you need to look a little harder at the way the data was generated.
This issue is by no means settled, but what you cite is one possible interpretation which may not fully fit the inherent issues in the way the data was collected.
Cheers. -
IQ does predict success
Research has demonstrated a strong correlation between IQ and sucess in all levels of jobs as well as marriage and other areas of life. The correlation is not equal to 1, so there will be smart people who fail and less smart people who succeed. The best article I could find quickly which supports this is from Scientific American: The General Intelligence Factor
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It's a plasma, contained by magnetic fields.However, it's not a simple plasma. It would have to be a high energy density plasma, in order to look solid and act solid.
The example I found of a Tocamac plasma is only red, but is 20-30 million degrees C. However, the lightsabers in the original (and therefore One True) Star Wars were white. This means they must be considerably hotter. The page I found on near-solid high energy density plasmas also talks about tens of millions of degrees - my gut feeling would be that to produce totally solid white plasma would require 40-50 million degrees C.
Now, plasmas at that kind of temperature could quite reasonably be expected to slice through almost anything - steel included. Furthermore, anything that was vaporised would be repelled by the magnetic field and thus travel AWAY from the wielder. This does mean that if you are fighting someone with a lightsaber, you will get sprayed with high-energy plasma every time they hit something.
There is one minor problem, though. Energy. If you want to maintain something at 50 million degrees, AND a containment field, a couple of duracel batteries won't cut it. Even lithium batteries will go flat very quickly. My guess is that the handle of the lightsaber, therefore, contains a wormhole linked to a gigantic anti-matter reactor.
All you REALLY need to do, then, is find out where your opponent's reactor is hidden and turn it off. Their lightsaber will then be useless. -
Mirrors for the files you need to do this......
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Re:just to remind that
This is not what the parent was trying to get at, but the melting of the ice sheets will cause the water level to drop in far northernly and southernly regions because of the gravitational pull caused by the ice masses themselves.
See here: http://www.newsandevents.utoronto.ca/bin2/020328c. asp -
"DRM"-hobbled garbageSays the article:
"Every other form of media has gone digital -- music, newspapers, movies,"
True. Music has gone digital, mostly because people take their un-copy-restricted CDs and rip them into MP3s. Then they can use the MP3 on as many computers and devices as they want, give it to friends, and have backups. Newspapers exist as un-copy-restricted HTML pages, which may be printed, sent to friends, and stored digitally without restriction.
What the publishing industry is peddling right now is copy-restricted garbage. It will be locked to a particular computer or device. I can't have backups of the text or lend it to a friend. Often I can't even print it. If the Microsoft operating system that stores the text wipes it out, oh well, go buy another one. Meanwhile the publishing industry salivates at the thought of copy-restricted electronic textbooks that expire after a single semester!
This copy-restricted garbage will not take off. If I want digital content, I'll go for something that does not have these ridiculous restrictions. Such unrestricted media can and will take off, because it has advantages--i.e. it's searchable, and cheap to distribute. For example, Wikipedia is far superior to its dead-tree equivalents for these two reasons alone. Also, the Amazon Shorts model looks promising. But I'll take a dead tree over copy-restricted garbage anyday.
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Re:Makes you wonder
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Re:Understanding protein structure..
Apparently, medical companies are in a rush to find protein structures that may lead to medical developments and patent them wildly.
The Welcome Trust funds several projects around the world that try and find as many structures before they are patented, and release them to public domain.
The way they do it is by massive trial and error. They test many environments for crystallization in parallel using robots and some neat tech. -
overbilled?
Don't these people know how hard it is to boot Windows on an AN/UYK-7(v)?
We should be in awe of Unisys, not arguing over who billed who. -
Run Our Own Internet Via CanX-2 nanosatellite
Imagine combining - Canada's University of Toronto's CanX-2 nanosatellite - which is the size of a carton of milk (shot out of a high veolcity canon - also a Canadian invention) - with WiMax. No more phone lines (also a Canadian invention) for the new publicly owned controlled internet.
Now we know the crazies in the USA shadow government will try to jam the system - but I am sure that a 15 yr. old hacker could solve those issues in a few days.
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Re:lol. political awards anyone?Ummm, yes and no?
;) I certainly can't explain it well. (Googles)http://www.upscale.utoronto.ca/GeneralInterest/Ha
r rison/BlackHoleThermo/BlackHoleThermo.htmlhttp://imagine.gsfc.nasa.gov/docs/ask_astro/answe
r s/011125b.htmlhttp://library.thinkquest.org/C007571/english/adv
a nce/core3.htm -
Re:Radiation - Seems to be a recurring problem.
I'm afraid nothing that currently exists can shield gammas and at the same time let RF out. Microwaves are relatively long wavelengths (compared to light), so screens can be made to let visible light through but block the microwaves. For gamma radiation (much, much shorter wavelengths than microwaves), the only shield is thick pieces of "high-Z" material such as lead or steel. Cobalt-60 has fairly high evergy gammas (~1 "MeV" in energy), so you'd need a good-sized plate of Pb to block it (e.g. see http://www.utoronto.ca/safety/RadTraining/Module7
. htm; in it they show that a 1.1cm thick lead sheet will reduce the gamma intensity from a Co60 source by 50%). Steel is worse...I *think* you'd be looking at ~ 1" thick for 50% reduction. As the reduction is exponetial with thickness, you'd need many times this quoted thickness to drop the intensity to e.g. 1% (1/2 * 1/2*1/2*.....). -
Re:Marginal Cases
to take the word processor analogy: paragraphs, not characters.
I'm sure that e. e. cummings ("paragraph? what's a paragraph?") wouldn't have liked that "feature"...
Eric
View your HTTP headers here -
Re:I never understood the communication aspect...
Without going into a long winded explanation, we know that 'spooky action at a distance' (more technically called non-locality) is a real phenomenon based on a theorem called 'Bell's inequality'.
Here's what that theorem says, in fairly simple terms:
If the system is merely the measuring of characteristics that pre-exist, but are unknown (like your pennies), there is a certain statistical distribution that will occur over a series of measurments of those characteristics.
Quantum mechanics predicts a different distribution of the series of measurements.
A substantial number of experiments have demonstrated that the statistical results confirm the non-local explanation of events.
There's a pretty good overview (if a bit technical) of Bell's Theorem here . -
Introduction to Quantum Computer
While we are on the subject of Quantum Mechanics. Check out Caltech's website on Quantum Computers.
I would also like to put you towards HP's Research on it.
The future is quantum mechanics, no matter the subject. -
Re:Setec Astronomy
Funny you should mention the discrete logarithm problem, given the fact that this scheme has suffered the same fate as factoring.
From the article referenced in the link:A major breakthrough in understanding the power of quantum computers came in 1994, when Shor showed how, with a quantum computer, one can factor large numbers using a number of computational steps comparable to the number of steps needed to multiply two numbers. In other words, if we allow quantum computational steps, we can factor efficiently. Many public-key encryption systems in use today require that factoring large numbers is exponentially harder than multiplying. That is, we need that encoding the information is roughly as easy as multiplying, but cracking the code is exponentially harder and thus infeasible. Another widely used class of public-key encryption systems assumes that finding discrete logarithms in various mathematical groups is hard, but Shor also came up with an efficient algorithm for finding discrete logarithms. This algorithm can easily be generalized in order to crack any of the discrete logarithm based cryptographic systems. Shor won the 1999 Godel prize for this work. His factoring algorithm was the topic of his first distinguished lecture.
People here seem to think that this breakthrough is limited to factoring, when it's apparent that it's equally applicable to all one-way functions. All that's needed is to construct the appropriate algorithm, and have a quantum computer to run it on. -
Re:Question About Discrete Logarithm
Found this snippet here:A major breakthrough in understanding the power of quantum computers came in 1994, when Shor showed how, with a quantum computer, one can factor large numbers using a number of computational steps comparable to the number of steps needed to multiply two numbers. In other words, if we allow quantum computational steps, we can factor efficiently. Many public-key encryption systems in use today require that factoring large numbers is exponentially harder than multiplying. That is, we need that encoding the information is roughly as easy as multiplying, but cracking the code is exponentially harder and thus infeasible. Another widely used class of public-key encryption systems assumes that finding discrete logarithms in various mathematical groups is hard, but Shor also came up with an efficient algorithm for finding discrete logarithms. This algorithm can easily be generalized in order to crack any of the discrete logarithm based cryptographic systems. Shor won the 1999 Godel prize for this work. His factoring algorithm was the topic of his first distinguished lecture.
Looks like the algorithm has already been found...just waiting for the hardware to run it on at this time. -
Re:Sure bash on...
Here's something for you to read.
http://www.news.utoronto.ca/inthenews/archive/2005 _06_17.html
Toronto has had record number of smog days this year. So your ideas of dropping pollution levels are certainly wrong. Smog days mean that particulate matter is passing above a threshold value at which breathing becomes difficult. Much of the smog "arrive here in prevailing winds from Illinois, Indiana, Kentucky, Michigan, Minnesota, New York, Ohio, Pennsylvania and Tennessee". So it is coming from a fair distance away.
And I CAN say the US Govt isn't doing anything because it has pulled out from the Kyoto Protocol for the sake of $$$
Here
Here
and here
If you knew anything about the middle class of the Chinese, you would know that it is near impossible to own a car given the wages, the prices and the taxes. The middle class isn't the same as the middleclass in Western societies. Middleclass over there means you're just not peasant class. Which is hardly anything to be proud of.
In a global society, you can't point at others until you've pointed at yourself first. -
Many corrections... (check the official site!)
This entry is wrong! Canada is a quarter partner in what will be the world's largest telescope when it is complete in 2014. The telescope, which is in preliminary design stages will be 30 m in diameter and consist of over 700 mirror segments that will work together to create a telescope that will be capable of producing Hubble Telescope type images from Earth. A lot of groundbreaking adaptive optics work is being carried out at the National Research Council Herzberg Institute of Astrophysics in Victoria, B.C. and AMEC Dynamic Structures which is designing the telescope's dome and other components. The Official Canadian Website is at http://tmt.astro.utoronto.ca
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Official Canadian Site
The official site of the Canadian aspect of the project can be found here: http://tmt.astro.utoronto.ca/
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Re:Obnoxiously Large Telescope
I assume the original article is referring to the joint US-Canadian venture entitled whose working title is TMT (Thirty Meter Telescope). In which case you can relax, they have picked an inflation-proof name.
http://lot.astro.utoronto.ca/ -
What are you, retarded?The UN is not far from al Qaida?
Try reading a little, you freaking moron. You can start with the Universal Declaration of Human Rights, which reads in part:Article 1. All human beings are born free and equal in dignity and rights.They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood.
Article 2. Everyone is entitled to all the rights and freedoms set forth in this Declaration, without distinction of any kind, such as race, colour, sex, language, religion, political or other opinion, national or social origin, property, birth or other status. [...]
Article 3. Everyone has the right to life, liberty and security of person.
Article 4. No one shall be held in slavery or servitude; slavery and the slave trade shall be prohibited in all their forms.
Article 5. No one shall be subjected to torture or to cruel, inhuman or degrading treatment or punishment.
Article 6. Everyone has the right to recognition everywhere as a person before the law.
Yeah, I think Osama bin Laden wrote that.
The UN has saved billions of lives through the World Health Organization and Unicef. BILLIONS. You remember smallpox, right? Maybe you don't. That's because it's the only major disease that has been effectively eradicated from the planet. Smallpox killed 300 - 500 million people in the 20th century, and you know who killed smallpox? The effing UN! (Why do I doubt you'll even read that link?)
This isn't saying that the UN is blameless or perfect. Like any large organization, the UN has to wrestle with bureaucracy, and the UN has challenges that are unique to any organization. But by any standard at all, the UN is one of the most powerful achievements for freedom, liberty, equality, justice, and health that humanity has ever known. Take some time and learn about what the UN does and about its record for success from people other than Bill O'Reilly. Please. Billions of people around the world whose lives are improved by the work the UN does will thank you for it.
You can be against the UN administration of the Internet without saying stupid shit like the "UN is not far from Al Quaeda". Sorry about the anger of this post, but seeing such blatant ignorance and lies getting modded up really agitates me. -
The best results..
Are achieved when the lie is plausible. And a behemoth of an organization is always slow to respond. You can compare any large organization to a garbage can! Lyndon et al have discussed this model for explaining strange behaviour of large organizations. http://choo.fis.utoronto.ca/mgt/DM.garbage.html
Basically change must be incremental for it too succeed in a garbage can.