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Domain: bestweb.net
Stories and comments across the archive that link to bestweb.net.
Comments · 14
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$10 Thermal Imager from a porch lightI was looking for an inexpensive option for thermal imaging and I came across this project for a $10 thermal imager using a automatic porch light and a frensel lense.
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Re:Parachuting
None of the space shuttles have ever had ejector seats, they were rejected as too expensive, bulky and heavy.
The WWP member (see his other posts, propoganda and check the link too) has it quite wrong again.
They were used on STS-1, STS-2, STS-3, and STS-4 -
Re:Shuttle Emergency Egress systems.
The Soviet Buran shuttles had ejection seats for four crew.
Another slashdot reader mentioned the ejection system of the F-111 . So I looked it up. The crew of the F-111 didn't have separate ejection seats. The whole crew compartment gets ejected. IIRC a crew compartment ejection seat was considered for the shuttle.
Question: If the shuttle was built for the USAF, not for NASA, would the extra money for a capsule ejection system have seemed worthwhile?
Mind you, even a whole capsule ejection system would only have worked at certain altitudes and speeds. But it would have been much more likely to save lives than the egress pole that was added after the Challenger disaster.
(I am listening to a NASA press conference as I type this. The spokesperson answered a question about flight data recorders. The shuttle doesn't have a hardened "black box".)
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However, his later jump......was a bit faster:
His later jumps were much more stable, and with a functioning 6 foot drogue, he achieved a terminal velocity of 702 MPH! He is still the holder of several world records, including longest (4.5 minutes) and highest freefall (81,000 feet) as well as highest bailout.
Source: The Ejection Site -
Re:Awesome.
According to this page, Ultrix was a BSD derivative. The versions of Unix that ran on PDP's and Vaxes were probably from AT&T and then later BSD.
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Not that great
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French Impressionist?
or Van Gogh? Rembrandt? Max Fleischer?
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NASA's Official RepsonseRead NASA's Official Repsonse
Danno Marx
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When two joke branches of science collide. . . .
Astrophysics and abiogenetical biology are the two most FUBAR branches in all of Science. Both branches religiously attempt to rectify random creation with probability. When the attempt fails, they brush aside the entire problem, as they believe their models are the only possible explanation short of God. The fact of the matter is that we know nothing about how our universe came into existence, or how life began in the Universe, save that all our current models could not be true. Unfortunately, instead of trying to find new models, we have defended them with a fervor rivaling the most devout zealots of any religion (with less excuse for doing so than any religious person.)
What many people forget is that one solid piece of negative evidence absolutely refutes a theory, regardless of how much favorable evidence that theory has behind it. For example, the equation:
(bn - 1)/(b - 1) = b(n-1) +
works for all b and n. Well, all b and n except b = 1, and all n > 0. That's an incredible success rate for the equation. There are literally infinte conditions it satisfies. Yet, Mathematicians would rightfully scorn anyone who suggested that the formula was viable and that just because it didn't work in a few anonomalous circumstances doesn't mean that it shouldn't be adopted as a general rule. To suggest such a thing shows a fundamental misunderstanding of the Scientific Method.
Yet the great majority of astrophysicists and geneticists/evolutionists (whom I collectively called abiogenetical biologists, those who concern themselves with the origins of life from nonlife) carry this misunderstanding. I will list some general problems with which the two branches have yet to contend (and will never be able to do so as long as they adhere to their current models) and then--for the dimmer of you--explain why basic flaws in our models mean that the conjecture about a "habitable zone" is a waste of our time, bandwidth, and brainpower.
From the Realm of Astrophysics
I have seen many posts attempting to describe planetary surface temperature as a function of atmospheric gases and distance from the sun. This has been tried with Venus (viz. Sagan et al.) and has failed miserably. Sagan attempted to explain Venus' 800 degrees Fahrenheit surface temperature by attributing it to a "Super Greenhouse" effect. Gunnar Heinsohn had a nice response to that absurdity:
If the Venus gases enable a runaway greenhouse effect of 800 degrees F wouldn't that allow us to solve all our energy problems, i.e., wouldn't that give us a perpetuum mobile? Shouldn't we put a Venus gas mix in a glass box, expose it to the sun and, then, reach a temperature sufficient to heat steam up to the level of driving turbines? Wouldn't we even have an advantage over Venus which, after all, cannot put a glass lid on its atmosphere?
I am not attempting to suggest that planetary surface temperature as a function of distance from the sun and atmospheric makeup is always false. The Earth seems to perform fairly well under the function. However, one solid piece of evidence negating the calculus is enough to render the entire thing moot. It would be senseless to use such a method to try to estimate appropriate planetary distances for conditions favorable to life.On an even more roguish note, we don't even understand gravity (for those of you who don't understand nerd-authored physics, see this simplification), much less are we prepared to use our understanding to calculate life-favoring gravitational conditions as a functions of planetary size and density. If someone attempts to dispute this, I will be happy to illustrate further with tangible examples.
From the Realm of Abiogenesis
Planetary conditions can never be suitable for the spotaneous generation of life. At least, not so long as our Universe is only 20 billion years old. I cut and paste from this site, which is a discussion of abiogenesis by Alexander Mebane:
Dismissing as unrealistic the idea that either DNA or RNA could ever have spontaneously "evolved", because of the complexity of those purine base + sugar + phosphoric acid structures,t he asks what could have been the simplest possible "pre-living" chemical assemblage that might have been able to generate the essential quality of life, self-replication. Generously oversimplifying to the maximum degree credible (or beyond), he proposes (p. 296) that the first "proto-life" might conceivably have emerged from a set of as few as ten very small "primitive enzymes", each one a mini-protein of only 25 links, and all constructed from a set of only four amino acids, rather than the twenty that Nature now employs. Assuming for the purpose the real natural occurrence of a "primordial soup" that consisted exclusively of those four amino acids (which is of course, a simply ridiculous postulate), he proceeds to show that, under these absurdly favorable conditions, the probability of "spontaneously", or accidentally, forming the requisite set of molecules would be about 1 in 10^150. So, if something like 10^150 random trials were available, the thing might really have happened. But he had previously calculated (p. 126) that, if one assumes that the Earth was covered by a 10-km-deep layer of "soup", and that random trials went on at the rate of one billion per second in every cubic micrometer (billionth of a cubic millimeter) of that ocean for one billion years (the maximum time that really elapsed before life appeared), only 1.5 x 10^62 separate tries could be made. (I have checked this calculation, and found it correct.) This number is so invisibly tiny compared to 10^150 (far tinier than a bacterium compared to the whole Solar System!) that the spontaneous natural formation of the ten mini-enzymes is thus demonstrated to be strictly impossible. This amounts to a proof that, even when making the most favorable assumptions conceivable, one is simply forbidden to take seriously the proposition that "Life on Earth must have arisen spontaneously, in some natural and unintentional way...
Conclusion
Now, for those of you who don't understand why all of these problems with the methods of the scientists who dedicated themselves to this frivolous study render the study a complete waste of human resources, I will explain. This kind of conjecture is much like man's early attempts to fly by pasting feathers onto one's arms and jumping off a cliff. This was a waste of time, perfectly good paste and feathers, and a waste of a (debatably) valuable human life. No scientific progress was gained by performing this feat. It was based upon erroneous presuppositions. The only good it did was to serve as an example of what not to do.
Leave conjecture to SciFi writers. They're better at it (and they don't spend nearly so much time or energy doing so.)
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Monocular HMD and YopyI was in the Daeyang/Yopy Booth at Comdex. They showed a monocular display hooked up to the Yopy. Here is a picture it: monocular headset
Daeyang is making the Yopy headsets. They are the first portable products to use a new kind of display technology: LCOS.
LCOS stands for Liquid Crystal on Silicon, and is essentially liquid crystals smeared on the top surface of a computer chip, with coverglass ontop of this sandwich. It allows very high resolution displays, with small diagonals and thus low cost. The power consumption is also very low (as low as 20mW for an SVGA-like display). Daeyang is using LCOS devices from my company: MicroDisplay Corp.
We, MicroDisplay Corp, are making these LCOS chipsets in the East Bay of San Francisco and are the only company in the world shipping LCOS product out the door daily!
Also, at COMDEX, Daeyang previewed their line of cell-phones that will be released running IMT-2000 mid-2001: SVGA resolution cellphones
The yopy is listing for $500. The binolcular HMD by Daeyang is listing for 800$. They have a new monocular and binocular headmount that use folded optics; the monocular one will be priced at significantly less than the binocular product: prism optics
Here is a picture of the binocular one: binocular headset
We also supply LCOS devices to MicroOptical and other headmount companies, one doing augmented reality for surgeons.
___________________________
Dr. Mary Lou Jepsen
Chief Technology Officer
MicroDisplay Corp
3055 Research Drive
San Pablo, CA 94806
http://www.microdisplay.com
mlj@microdisplay.com
+1.510.243.9515 (ph)
+1.510.243.9522 (fax)
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Monocular HMD and YopyI was in the Daeyang/Yopy Booth at Comdex. They showed a monocular display hooked up to the Yopy. Here is a picture it: monocular headset
Daeyang is making the Yopy headsets. They are the first portable products to use a new kind of display technology: LCOS.
LCOS stands for Liquid Crystal on Silicon, and is essentially liquid crystals smeared on the top surface of a computer chip, with coverglass ontop of this sandwich. It allows very high resolution displays, with small diagonals and thus low cost. The power consumption is also very low (as low as 20mW for an SVGA-like display). Daeyang is using LCOS devices from my company: MicroDisplay Corp.
We, MicroDisplay Corp, are making these LCOS chipsets in the East Bay of San Francisco and are the only company in the world shipping LCOS product out the door daily!
Also, at COMDEX, Daeyang previewed their line of cell-phones that will be released running IMT-2000 mid-2001: SVGA resolution cellphones
The yopy is listing for $500. The binolcular HMD by Daeyang is listing for 800$. They have a new monocular and binocular headmount that use folded optics; the monocular one will be priced at significantly less than the binocular product: prism optics
Here is a picture of the binocular one: binocular headset
We also supply LCOS devices to MicroOptical and other headmount companies, one doing augmented reality for surgeons.
___________________________
Dr. Mary Lou Jepsen
Chief Technology Officer
MicroDisplay Corp
3055 Research Drive
San Pablo, CA 94806
http://www.microdisplay.com
mlj@microdisplay.com
+1.510.243.9515 (ph)
+1.510.243.9522 (fax)
-
Monocular HMD and YopyI was in the Daeyang/Yopy Booth at Comdex. They showed a monocular display hooked up to the Yopy. Here is a picture it: monocular headset
Daeyang is making the Yopy headsets. They are the first portable products to use a new kind of display technology: LCOS.
LCOS stands for Liquid Crystal on Silicon, and is essentially liquid crystals smeared on the top surface of a computer chip, with coverglass ontop of this sandwich. It allows very high resolution displays, with small diagonals and thus low cost. The power consumption is also very low (as low as 20mW for an SVGA-like display). Daeyang is using LCOS devices from my company: MicroDisplay Corp.
We, MicroDisplay Corp, are making these LCOS chipsets in the East Bay of San Francisco and are the only company in the world shipping LCOS product out the door daily!
Also, at COMDEX, Daeyang previewed their line of cell-phones that will be released running IMT-2000 mid-2001: SVGA resolution cellphones
The yopy is listing for $500. The binolcular HMD by Daeyang is listing for 800$. They have a new monocular and binocular headmount that use folded optics; the monocular one will be priced at significantly less than the binocular product: prism optics
Here is a picture of the binocular one: binocular headset
We also supply LCOS devices to MicroOptical and other headmount companies, one doing augmented reality for surgeons.
___________________________
Dr. Mary Lou Jepsen
Chief Technology Officer
MicroDisplay Corp
3055 Research Drive
San Pablo, CA 94806
http://www.microdisplay.com
mlj@microdisplay.com
+1.510.243.9515 (ph)
+1.510.243.9522 (fax)
-
Monocular HMD and YopyI was in the Daeyang/Yopy Booth at Comdex. They showed a monocular display hooked up to the Yopy. Here is a picture it: monocular headset
Daeyang is making the Yopy headsets. They are the first portable products to use a new kind of display technology: LCOS.
LCOS stands for Liquid Crystal on Silicon, and is essentially liquid crystals smeared on the top surface of a computer chip, with coverglass ontop of this sandwich. It allows very high resolution displays, with small diagonals and thus low cost. The power consumption is also very low (as low as 20mW for an SVGA-like display). Daeyang is using LCOS devices from my company: MicroDisplay Corp.
We, MicroDisplay Corp, are making these LCOS chipsets in the East Bay of San Francisco and are the only company in the world shipping LCOS product out the door daily!
Also, at COMDEX, Daeyang previewed their line of cell-phones that will be released running IMT-2000 mid-2001: SVGA resolution cellphones
The yopy is listing for $500. The binolcular HMD by Daeyang is listing for 800$. They have a new monocular and binocular headmount that use folded optics; the monocular one will be priced at significantly less than the binocular product: prism optics
Here is a picture of the binocular one: binocular headset
We also supply LCOS devices to MicroOptical and other headmount companies, one doing augmented reality for surgeons.
___________________________
Dr. Mary Lou Jepsen
Chief Technology Officer
MicroDisplay Corp
3055 Research Drive
San Pablo, CA 94806
http://www.microdisplay.com
mlj@microdisplay.com
+1.510.243.9515 (ph)
+1.510.243.9522 (fax)
-
State of the art callbacks are signal/slots.What you are describing is C callbacks. Please read my glossary of terms for my callback library. You will find that I know exactly what a signal/slot is. Signal/Slot is little more than an abstraction of a Caller and a Callee, with the additional concept of multiplicity. It can be done as a simple extension of Hickey's callback model when combined with lists.
My comparison is completely fair as I was comparing a signal/slot implementation with another signal/slot implementation from the Gtk--. Both have multi-callbacks. Both have signal concept. Gtk-- skips the slot concept, but any function can be used as a slot. One just happens to be 30 times faster. Since they do the exact same thing, I can definately say although Qt is a very nice library, it is not the most efficient C++ library out there.
For independent confirmation of what I have said please read this usenet post. That user found a 25 times difference between template based (gtk--) and string based (Qt) signal/slot implementations. We have improved since then.
But you are quite capable of testing it out for yourself. Grab my library, libsigc++. I think you will be surprised by exactly how much a callback system can do. Qt was only scratching the surface.
--Karl
