Domain: nrc-cnrc.gc.ca
Stories and comments across the archive that link to nrc-cnrc.gc.ca.
Comments · 45
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Re:How many of these damn things are there?
Ok - the previous 4 comments, and usually all that relate to cryptocurrency on
/., are negative and/or pessimistic.
Just an open "Ask Slashdot" since there aren't that many posts here for everyone: "Does everyone here really think BitCoin, Ethereum or Ripple are that bad?"
I have some of all of them, and obviously the sketchier ones (like bezop) are riskier, it seems like the ones above are destined for something, maybe not in the next couple of months, but certainly the next decade.
some info:
- Pfizer, AMD and Ernst & Young have joined the Enterprise Ethereum Alliance
- Samsung announced that they are manufacturing ASIC processing chips for Bitcoin (specialized mining hardware)
- RobinHood announced the addition of cryptocurrencies to their trading app. Over 1,000,000 people are now on the waiting list
- The Canadian government launched a trial to use Ethereum for the transparent administration of government contracts
Just curious to see what people think, if we're talking about losing money in cryptocurrency and there's nothing but these negative comments. -
Canada's is still going
The Canadian National Research Council's "telephone talking clock" is still active,
English: 613-745-1576
French: 613-745-9426They also run an NTP server, shortwave time broadcasts, web-based clock, modem-based "simple time service", and daily time broadcasts on CBC radio.
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2-stage SSH with X forwarding
I'll mention this because it's what I'm doing and I haven't seen anyone else suggest it yet.
What I personally do for remote help is to use SSH with X forwarding directly, without using anything like VNC. I always set up SSH servers on non-default ports and also install fail2ban "just in case" a remote attacker actually finds the SSH servers and tries to brute-force them -- of which no attempt has ever been made so far. [And I can say that because I also set up 'logcheck', tweak logcheck to filter out noise so that it only reports actual issues, and then I actually read the resulting emails it sends.] In addition I also set up a "pre-shared" ssh key with no password and copy the key to the remote router so that the password to log into the router is not passed over the 'net, and also disable root logins. (Okay -- call me paranoid.
:-P)One place I've found with simple instructions for setting up pre-shared ssh keys:
http://rcsg-gsir.imsb-dsgi.nrc-cnrc.gc.ca/documents/internet/node31.htmlAnd although I know I could do the same thing to log into the user's box through the router via pre-shared keys and ssh-agent forwarding:
http://unixwiz.net/techtips/ssh-agent-forwarding.html
instead I don't actually bother to do so, and just use a normal ssh password login to the user's box.Login steps to get to user's box:
- log in via SSH to the remote router, with X fowarding
ssh -l (normal_user_username) -X -p (port) (remote_router) # ex: ssh -l mooha -X -p 1022 router.mydomain.com
- log in via SSH (as a normal user) to the user's box, with X forwarding
- su to root on user's box
- su to that user
- tell the user to quit the program they're having a problem with
- run the specific program they're having a problem with myself and have a lookUpsides:
- secure
- gives user some privacy (can't see their screen)
- never "take over" the user's mouse
Downsides:
- can't see the user's screen
- need to know the actual program name to run, rather than using the menus in the window manager
- difficult to have a look at "non-application" programs such as desktop widgets (which is usually not a problem) -
Security
I'm sure there are going to be dozens posts about the evil conservative government and how they have all their ministries scared to say anything about anything. However, and despite all the cool stuff that the NRC does (like 3d scanners, heated concrete, etc), they do do a lot of top secret research. I'm not surprised that a request involving a foreign government organization was met with a bureaucratic response.
Here is a quick list of some of their best and most important work. Probably a much more interesting article than the fishing expedition of the Ottawa Citizen.
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Re:Unlikely
The objects were observed during two days, which were between 600 and 8000 km removed from earth, between the sun and the earth, as they were seen passing in front of the sun. The escape velocity in that range is 10.7 to 7.4 km/s. As we didn't have an impact and haven't developed a ring or an extra satellite they must have had at least this speed relative to earth. The article doesn't mention at what exact times the observations were made, but according to this calculator there were 13 hours of daylight on those dates at that location, so to have those observations made on two days the objects kept passing within this distance interval during at least 14.5 hours (11 hours night time plus the 3.5 hours observation time mentioned in the article). At 7.4 km/s the objects were spread out over at least 390,000 km and traveled that distance relative to the earth, and yet they all managed to pass within a distance of 600-8000 km from the earth surface, and in front of the sun seen from one observatory and not from others.
How likely is that?
For some bizarre reason the parent post was modded down, so I'm quoting it, as it's one of the most clearly thought out posts in this entire thread.
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Unlikely
The objects were observed during two days, which were between 600 and 8000 km removed from earth, between the sun and the earth, as they were seen passing in front of the sun. The escape velocity in that range is 10.7 to 7.4 km/s. As we didn't have an impact and haven't developed a ring or an extra satellite they must have had at least this speed relative to earth. The article doesn't mention at what exact times the observations were made, but according to this calculator there were 13 hours of daylight on those dates at that location, so to have those observations made on two days the objects kept passing within this distance interval during at least 14.5 hours (11 hours night time plus the 3.5 hours observation time mentioned in the article). At 7.4 km/s the objects were spread out over at least 390,000 km and traveled that distance relative to the earth, and yet they all managed to pass within a distance of 600-8000 km from the earth surface, and in front of the sun seen from one observatory and not from others.
How likely is that?
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A better link: Herzberg Institute directly
I hope this doesn't cause a slashdotting of the Herzberg Institute, but...
http://www.nrc-cnrc.gc.ca/eng/news/nrc/2010/12/08/exoplanet-marois.html -
Re:What next? Cameras?
I found a link:
Converting classic paintings to 3D geometry
They even converted a scene from 2001: A Space Odyssey
Make3D from Stanford University.
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Re:What next? Cameras?
I found a link:
Converting classic paintings to 3D geometry
They even converted a scene from 2001: A Space Odyssey
Make3D from Stanford University.
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Re:Non-Toxic inert?
Is uranium water soluble?
My understanding was that uranium was not, irradiated uranium grains have been intact for over a billion years.
Uranium oxide (UO2) is slightly soluble. (same source).
So this discovery seems not aimed at Uranium waste management, but perhaps at medical waste.
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Inefficiency of CFLs
The poor Power Factor rating of CFLs means that the power grid must provide more energy to start them. The consumer may save money at home, but unless the power factor of CFLs can be improved, the electrical grid itself will have to be upgraded if we all switch to CFLs.
But there's no "if" because governments have already legislated the elimination of incandescent bulbs!
An explanation of the power factor (search for the heading "Power
Factor and Switching")
http://irc.nrc-cnrc.gc.ca/pubs/cp/lig3_e.htmlMore summaries of problems:
http://www.cours.polymtl.ca/inf1040/2008automne/Olivier_CanadianReviewDec2007.pdf
http://sound.westhost.com/articles/incandescent.htmCurrent research:
http://qnc.queensu.ca/story_loader.php?id=49db90a6e3e3dSearch for "power factor":
http://www.bchydro.com/powersmart/technology_tips/buying_guides/lighting/compact_fluorescent_lamps.htmlHere, you'll see that the "requirement" for "Energy Star" labelling is
a power factor of only 0.50!
http://oee.nrcan.gc.ca/residential/business/manufacturers/specifications/compact-flour.cfm?attr=12 -
Panspermia
There is another article from last year regarding the meteorites found in Antarctica, which were found to be loaded with amino acids. I also remember reading something about actual microbes/bacteria that were found to have entered the atmosphere from space quite recently, but I can't remember the link. It could have been this current story, considering the paper dates from 4 years ago.
I see no reason that this could not be valid. Comets and asteroids have near misses with planets quite regularly and the occasional glancing blow will surely take some of whatever is on the planet out into space. As the paper states, these micro-organisms are viable but don't respond to culturing. Which could mean they were alive but are dormant and don't respond to conditions here on earth.
Being previously undiscovered doesn't really prove anything as the Amazon is full of insects and other life that have yet to be "discovered" by man, but this is not definitively disproving panspermia. IMHO, this is one of the prime reasons for humans to visit Mars, as it is very difficult to get a robot to be able to spot these kinds of organisms, especially if they are not currently alive. The conditions on Mars are not favourable for large organisms, but if there is water ice, then you have the capability of getting H2 and O2 at the least. And as Mars has no magnetic field (to speak of), there would be large amounts of mutating cosmic rays hitting the surface continually for billions of years. It would be odd if nothing came of it.
I've been reading some of Asimovs later scientific essays, and he describes how you can predict with some certainty which planets are likely to have a magnetosphere. Basically, you need a reasonably rapid rotation, and a molten or high temperature metallic core which "sloshes" about as the planet spins. This core acting against the outer layers of the planet causes the magnetic field. The only real reason our planet is special, regarding life, is that we have an exceptionally large moon, too large in fact as conventional wisdom goes, to have been formed by capturing passing debris. We are almost a binary planet system, and that is pretty rare. So the possibility of life forming actually in space (rather than on another planetary body) has to be considered.
If we send men to Mars and they find similar micro-organisms there, then it is possible they came from space rather than evolved natively. Especially if there are no other traces of activity that can be construed as being the result of living organisms.
Interesting stuff, which can never be verified while we sit here exploring from a distance. -
Correct URL
The correct URL of the COPE study is:
http://irc.nrc-cnrc.gc.ca/ie/cope/index_e.html -
The reversals frozen in the mid-Alantic ...
out flowings aren't due to flips of the Earth's magnetosphere?
mmm... Geologists have been claiming magnetic flips since Warner. From the National Research Council of Canada:
http://www.nrc-cnrc.gc.ca/eng/education/astronomy/tapping/2007/2007-05-29.htmlThe Atlantic Ocean is getting a few centimetres wider each year. Molten rock is emerging from the Earth's mantle at the Mid-Atlantic Ridge, providing new seabed, and as it solidifies, records the magnetic field. As we move away from the Mid-Atlantic Ridge, we encounter progressively older rocks, forming a continuous record many millions of years long. It turns out that on the average, the Earth's magnetic field reverses every 500,000 years or so. The rocks tell us the last reversal happened about 780,000 years ago, making the next reversal overdue. At the point of transition the Earth's magnetic field vanishes, along with our protection. Strange changes in the magnetic field in the South Atlantic could indicate the transition has started. If this is true, what can we expect?
The literature if filled with research using magnetic reversals to prove various hypotheses. Also, the magnetic reversal is sited as a proof against Creationists contention that the Earth is less than 25K years old and the magnetic field hasn't reversed itself.
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Re:Close mindedness.
Microsoft development tools are not top-notch. They have a few nice features, like intellisense, which Microsoft developers get addicted to and then can't live without.
Since you mentioned Orcas, am I going to be able to use it with VS2005 solution files? Or will it convert the solution files into it's own format, preventing me from working with people who haven't upgraded yet? Backwards compatibility is the Achilles heel of Microsoft dev tools. Will it work with VS6 projects?
Speaking of solution files, when will they be in a format that is easy to understand, so if someone else modifies it at the same time I do, I can merge the changes together before committing? Or will I still have to revert my changes, re-do what I just did, and pray that nothing breaks?
And why on earth, when I have two 21 inch LCD screens, do I still need to have all my project files in a single window? X-code lets me separate them and scatter them all over the screen. If I'm using emacs I can open a different window for each source file. Even ED will let me do that, for crying out loud. Why did Visual Studio ruin the one thing that ED got right? (of course I'm assuming you can open up more than one terminal window. If you can't, then you have no hope with VS anyway).
If you can look at more than one file at a time, and your code is well written, you don't even need intellisense. And as for the class libraries, spend a year programming on Cocoa before you start claiming how good they are. Microsoft developers only think .net is good because windows before .net was so extremely bad (when you have to say myStruct.size = sizeof(myStruct) so the system can know which version you are using, things are just out of control).
By the way, reading your post, I just realized your post completely lacks substance. You didn't mention one good thing about MS, you didn't mention one bad thing about anything else. Did you actually have something real to complain about, or were you just flaming? -
New molecules...
Well, being a chemist, making a few new molecules in my undergrad thesis was a very cool thing to do, of course now I have to do it all the time, but every once in a while you make something really cool.
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not a single Linux desktop ..
"no Linux desktops have yet been installed"
It strikes me that thay attempted a roll out of a Linux desktop solution with no previous experience. They would have been occupied in bringing in an experienced company to do the job.
"half-a-million-pound cost of designing and implementing the system cost more than the estimated cost for a Windows XP installation"
What were they implimenting on the Suse desktop that required spending half a million pounds.
"usability problems with the original Gnome interface .. staff ripped out Gnome and replaced it with KDE"
Like what, Gnome is specifically designed to provide a rich user interface. Either of them can be replaced by a Windows look alike.
"For instance, existing Windows 3.1 public terminals used a program called Deepfreeze that rebooted the system at the end of each session, something that had to be re-engineered for Linux"
He's kidding, put a line in .bash_logout 'shutdown -r 0 now' and that's it. And besides which, why do you need to reboot at logout.
"Staff also found that the OS was storing information about the contents of public users' removable media, and for privacy purposes had to develop a script to delete this information"
Like where and how, Linux mostly uses /tmp to store temp files all you have to do is add another line to .bash_logout 'find /tmp/ -user $user -exec rm -r {} \;'. Or else put /tmp in a ramdisk and flush it to logout. -
Re:Talking about google maps...
Whereas Google Earth and the like, obviously, have more data they are still stored as separate images... (not sure why they needed to connect this one up into one image either, but it must be easier for them to analyse like that)
Maybe they couldn't get their hands on one of these. -
Re:Why no intercontinental cooperation?
Sure, the US could push for a multilateral approach to space exploration. Now, stop and think about the current state of affairs in the 'states and you'll see why this isn't likely to happen.
We do cooperate on some things, like the International Virtual Observatory Alliance.
Which amongst others includes contributions from :
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Re:Only solves 50% of the problem
Actually as you go deeper underground the temperature of the soil gets closer and closer to the average yearly temperature in that area as shown here
How fast the temperature approaches the yearly average as depth increases depends on the type (and moisture content) of the soil, but as a rough guide, at 8m depth the temperature is very close to the yearly average.
Note that this is not valid for extreme depth (or vulcanic areas) for the obvious reason ;)
BTW, the graphic was taken from here - if you want to know the depth at which the yearly variation of temperature has 1% of the amplitude of the variation outside, look for "Table I. Depth of Penetration of Diurnal and Annual Temperature Cycles" (sorry, no anchor in doc) and check the column "Depth Year (m)" -
Re:Only solves 50% of the problem
Actually as you go deeper underground the temperature of the soil gets closer and closer to the average yearly temperature in that area as shown here
How fast the temperature approaches the yearly average as depth increases depends on the type (and moisture content) of the soil, but as a rough guide, at 8m depth the temperature is very close to the yearly average.
Note that this is not valid for extreme depth (or vulcanic areas) for the obvious reason ;)
BTW, the graphic was taken from here - if you want to know the depth at which the yearly variation of temperature has 1% of the amplitude of the variation outside, look for "Table I. Depth of Penetration of Diurnal and Annual Temperature Cycles" (sorry, no anchor in doc) and check the column "Depth Year (m)" -
the website
err, perhaps a link to the actual Nanotech Institute website would be helpful? http://nint-innt.nrc-cnrc.gc.ca/home/index_e.html
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Re:Reducing the energy usageYou make a fluorescent bulb that isn't ugly and depressing, I'll replace my incandescents.
No one ever talks about the aesthetics of lighting a home. They are important. It is important to light your home beautifully. Most people recognize this instinctively and use the incandescent. Fluorescent lights are ugly, ugly, ugly. If you're saying we should all live in some sort of dystopian nightmare of completely artificial light, please say it clearly.
The Canadian Research Council says this about CFL:The Colour Rendering Index (CRI) of a lamp reflects how accurately the colour of an object can be determined under a given light source. Compact fluorescent lamps have a CRI of 82 (out of 100), which is considered excellent for fluorescent sources and good for artificial light in general. Incandescent lamps have a CRI of 97. Incandescent lamps provide excellent colour rendering because of the full spectrum of colour wavelengths present in the light they produce.
Naturallighting.com offers fluorescent and CFL lamps with a CRI of 91, which is better, but still not the 97 you get out of a regular incandescent bulb. Vita-lites cost seventeen dollars, compared with 4-7 bucks for a GE CFL, and under a dollar for the regular old incandescent. GE's CFL offerings (the type normally available in stores) are the soul-destroying 82 CRI variety and are thus unacceptable.
The CFL savings calc shows that even using the Vita-lites, you'd save money over the course of a year. I'm going to order one of those Vita-lites to see if it passes the aesthetic test. -
Machine Learning of Semantic RelationsPeter Turney's Learning Analogies and Semantic Relations falsifies the Ellerman's assertion that semantics is out of the reach of engineering. Turney's more recent Human-Level Performance on Word Analogy Questions by Latent Relational Analysis (Warning: PDF) shows an engine performing about as well as college-bound seniors taking the SAT verbal analogies test.
For a review of Peter Turney's group's accomplishment see "AI Breakthrough or the Mismeasure of Machine?"
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Re:Ack!
While I'm sure other countries will get in on a project of this magnitude, I think both the
/. summary and the original article in the Toronto Star are incorrect, I've never heard of a U.S. Herzberg Institute for Astrophysics, and I would be very surprised if one existed, since Gerard Herzberg was a Nobel Prize (chemistry) winning Canadian scientist. Not only there, there is already a National Research Council of Canada Herzberg Institute for Astrophysics in Victoria. A quick google search also didn't show any "U.S. Herzberg Institute".
Shame on The Star. -
Re:A standardized second.
The second is one of seven SI base units. It is defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom at zero kelvins.
The definition is made in terms of the most accurate way we have of measuring it - with the atomic clock. There's a description of how they work here.
In the future the definition may change - there are developments to produce "optical clocks" which are more accurate even than atomic clocks. Read about them here or here (subscription required). Of course, any new definition will be chosen to be compatible with the previous definitions, to within the accuracy afforded by those definitions.
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Re:I'd like to region-code my personal dataThat idea has been proposed in research literature, dubbed Privacy Rights Management (PRM):
Korba, Larry and Kenny, Steve (2002): Towards Meeting the Privacy Challenge: Adapting DRM. NRC paper number NRC 44956, November 2002, http://iit-iti.nrc-cnrc.gc.ca/iit-publications-it
i /docs/NRC-44956.pdfI have an interest in this and am looking at alternative approaches:
http://goanna.cs.rmit.edu.au/~crpearce/research/p
u blications/ifip-sec2005.pdfPS: Long time reader, but first post (loooong overdue!)
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Heated ConcreteWhat might be very interesting is if this technology could be combined with the conductive concrete developed by the Institute for Research in Construction which is part of the Canadian National Research Council. This technology was awarded a top prize by Popular Science Magazine in 1997.
These two technologies together might constitue a concrete used for roads that is both very flexible and also featured automatic snow and ice removal!
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Heated ConcreteWhat might be very interesting is if this technology could be combined with the conductive concrete developed by the Institute for Research in Construction which is part of the Canadian National Research Council. This technology was awarded a top prize by Popular Science Magazine in 1997.
These two technologies together might constitue a concrete used for roads that is both very flexible and also featured automatic snow and ice removal!
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Heated ConcreteWhat might be very interesting is if this technology could be combined with the conductive concrete developed by the Institute for Research in Construction which is part of the Canadian National Research Council. This technology was awarded a top prize by Popular Science Magazine in 1997.
These two technologies together might constitue a concrete used for roads that is both very flexible and also featured automatic snow and ice removal!
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Re:Desktop fusion is not new...
I'm sorry if my original post sounded arrogant or accusatory. I'm honestly interested in knowing more about this technology. I'm happy to be corrected when I'm wrong, but it really helps to have sources to check.
With regard to flux, as far as I can tell, no one has reported a Fusor-style setup with a flux higher than 1E8 neutrons/second or perhaps 1E10 neutrons/second (example, example). Assuming an operating distance of 1 m, that's less than 1E5 n/(cm^2 s).
By comparison, modern reactor setups achieve 2E15 n/(cm^2 s) flux, and spallation sources can achieve 1E17 n/(cm^2 s) (see Fig 1 here). This is why I characterized a Fusor as "low flux." The flux of a Fusor is useful for some things, but for most applications of neutron beamlines, it is too weak. (Of course, more than flux matters: energy distribution also matters.)
From what I know, Fusors are great for studying some aspects of fusion reactions and maybe conducting experiments on neutron properties. I've also heard of using it for neutron interrogation (example), where you irradiate a sample and see what happens (for instance for characterizing nuclear samples, material identification, bomb detection). So, yes, it is a neutron source. However, it is not competitive with high-flux sources, and is (I think!) too weak for neutron scattering, diffraction, and imaging experiments. This is why I claimed that a fusor was not a general-purpose neutron source.
This is also why no Fusor sources are listed on any "worldwide neutron source" lists, as far as I can tell:
http://neutron.nrc-cnrc.gc.ca/links.html
http://www.ncnr.nist.gov/nsources.html
http://www.neutron.anl.gov/facilities.html
http://neutron.neutron-eu.net/n_users/n_where_the_ facilities/n_worldwide
http://www.sciner.com/Neutron/neutron_facilities_w orldwide.htm
With regard to the universities you mentioned, it looks like the PULSTAR at North Carolina State is a reactor. The TRIGA at University of Illinois at Urbana-Champaign is also a reactor. If those were not what you were referring to, then I apologize.
To recap: I relent and agree that a Fusor is indeed a viable neutron source. However, I would like to point out that its flux is much lower than other sources, making it unsuitable for many types of neutron beamline experiments. If I'm wrong about any of this, please correct me. -
Re:Damn...
wannabes - its really called 'ed'.
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Re:Sponsored by the NRC?
I don't know if they're sponsors but it seems the NRC has put a bunch of papers in these conferences. I did a search for Systemics (a good choice because it's essentially a buzzword that wouldn't appear in many other places) and got a bunch of conference related hits.
I'm going to write something to the NRC. It certainly isn't good for their credibility to be publishing in bullshit conferences like this. -
Sponsored by the NRC?
Heh... it says that the NRC is a "technical co-sponsor" of the WMSCI 2005 on their web page, however, I can't seem to find ANY mention of WMSCI 2005 on NRC's website.
Why do you suppose that is I wonder? -
DRM for Privacy
I'd accept DRM technologies... for corporations, that is, to use our personally identifiable information in ways that owners deem fit. This paper suggests that DRM might work (though there are obvious difficulties wrt getting corporations and government to use it):
Korba, L., Kenny, S. "Towards Meeting the Privacy Challenge: Adapting DRM," 2002 ACM Workshop on Digital Rights Management, Held in Conjunction with the Ninth ACM Conference on Computer and Communications Security. Washington, District of Columbia, USA. November 18-22, 2002. NRC 44956.
Thoughts? -
Re:Good Use for Importing Stationary Objects"Educationally, people could truly "walk around" in a virtual museum."
True, though I don't think this is the right technology for that. Don't get me wrong, I think this is impressive and interesting, though it isn't the first or only 3D model from video motion software. However, for hi-fidelity virtualization of museums or artifacts I'm far more impressed with other approaches.
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Re:It's because....Hello again, here's some bits & pieces dug up with some cursory Google searches. Search for more on the lake name (Lak Ojibway) & I'm sure you'll find more on the 8200 BCE event.
- RealClimate piece mentioning the event.
- Google search that finds lots of info
- Abstract of a paper discussing the event
- looks like a map of the lake (PDF)
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Re:LED litA standard fluorescent bulb flickers at 60 Hz.
But an electronic ballasted compact flourescent that screws into a standard lamp base flickers at 25-40kHz. The compact flourescent technology causes no visible flicker, is smaller than the old magnetic ballast (which operated at the frequency of house wiring, 60Hz), and improved efficiency overall, losing less energy to heat in the ballast.
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Re:LED lit
>With a full wave recrifier, it will be off for tiny amount of time between pulses; almost certainly faster than the LED can turn off
Considering LEDs are used in TOSLINK circuits (and heck, gigabit fibre circuit), I really hope that isn't true!
An LED should shut off nearly instantly. I mean, how can one expect it to stay on but the rectifier diodes to turn off? :-)
>Also, the human eye can't detect a 120Hz flicker, the limit is around 48Hz
Directly, yes. Indirectly, the debate is still out there. -
Re:Out of curiousity...Not really true. Lidars and Ladars use time of flight (TOF) methods and phase shifting. These are used for long distance measurements (tens of meters to kilometers). Current accuracy of TOF is about 1 cm, with improvements using phase shifting. But measuring close objects can be hard and less accurate because the flight time gets so short.
Most laser scanners for close scanning (cm to several meters) use triangulation. Wide FOV versions can have ~1 mm precision and cover medium volumes. Narrow FOV versions can be precise to ~0.025-0.1 mm but often can only see at very close range (~10 cm to 1 m) over small volumes. One exception is the autosyncronous scanner from NRC of Canada that can measure on the order of 25 microns (~0.025 mm) over large volumes and a wide FOV, by using a narrow FOV camera that automatically follows the laser spot across a wide FOV. This also makes it "random access" which means it doesn't have to do raster scans (but can) but can trace out any shape you want.
Neptec Design Group has developed one of these for use in space. Right now, Neptec's laser scanner is being included as a required 3D scanner for analyzing the shuttle thermal protective system on orbit (tiles, RCC panels) for return-to-flight, as a result of the Columbia Accident Investigation Board report.
A good review of TOF and triangulation scanners (and structured light / fringe), including commercially available ones, is given in this paper, and here is a good list of some scanners and their type.
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Carbin? Deer Slaishdought eddyterrs...
... plllez eddyt obveeus spalyng erurrz. Carbon
:) -
Re:USA 2nd World?
When you have socialized healthcare you get what you pay for. That's why no medical advancements come out of nations with such systems.
Nonsense.
I work at Canada's National Research Council and can tell you that you're 100% wrong on this. -
Re:Wind Farms ain't necessarily all goodYou were joking I hope... because of all the buildings in all the cities of all the world, none interfere with the wind.
Are you joking? Have you ever seen a series of high-rise buildings that channel the wind and create a wind-tunnel effect? Read this report for some info about how Canada is dealing with this common effect.
You seem to miss my argument completely. Wind turbines are purposely designed to extract as much kinetic energy from the wind as possible.
Buildings, on the other hand, are (mostly) static objects that can channel and redirect wind. They don't take away it's kinetic energy (except a tiny fraction through friction from shear flows).
If you have any documentation that will demonstrate that the reduced convective flows will not affect regional temperatures or tailwinds used for migratory birds, or other large-scale environmental impacts, then please show me. I haven't seen any reports refuting these concerns, and windfarm advocates sidestep this issue.
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Re:How about 110v Light Bulb Replacements?
"Full spectrum" lighting is a scam. See FAQ about Lighting, Mood, and Performance.
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Re:not sure who to cheer for...
That a computer filed the application?
When I worked at the NRC, we were developing some software that tried to find holes in a knowledge-base. We once discussed the scenario of creating something good enough that it could find patentable ideas, and then just letting it run and generate IP for the NRC.
Of course, we never got that far..:-)
-Rob