When designing machinery or constructions, deflection under load is often the limiting factor.
In those cases the stiffness of the construction is much more important than the strength of the material.
Now the stiffness of a construction is determined by both the shape and the material stiffness or Young's Modulus.
But AFAICT, little if any progress has been made in improving the Young's Modulus of alloys.
Additionally, often the ultimate strength of metals isn't really important in a design. In general designers want to make sure that the stresses in the material don't exceed the proportionality limit.
When the book came out, it was the first sci-fi book in years that I couldn't put down.
And the film stayed fairly true to the book, which is also uncommon.
Technically, you could say that the Martian is more *engineering*-fiction; it's not about discovering new principles, but making stuff work. Even in ways it was never meant to, and without the proper means. In that aspect is also great *hacking* fiction.
As an engineer myself I loved it. Especially the book. Stuff going wrong is very recognizable in engineering practice. Every experienced engineer has had their "oh, shit" moments.
Circa 1990. 368SX-16 through a discount program at school during my bachelor's. If memory serves, it had a 40 MB harddisk. Didn't buy a DX so I could buy a deskjet printer as well. Installed MS-DOS 5.0 when it came out. Looked at QBasic, but didn't like it. Mainly used it to run WordPerfect and Turbo Pascal and later Turbo C.
At school we used a 386DX to run NASTRAN on Xenix. That was my first contact with UNIX.
I upgraded components over the years until I had a 486 around 1994. Installed OS2 2.0. Used IBM's compiler, but it was buggy and expensive. Installed GCC and GNU Make. Then a friend showed me Linux.
It must have been in 1996 when I downloaded a dozen floppies worth of Slackware in the evenings using my modem, and dove right in. I've been using Linux and later FreeBSD ever since.
The problem with all these powered lift gizmos (like the Williams X-jet and the Hiller VZ-1) is that you tend to fall out ouf the sky when your engine fails... The Hiller VZ-1 which is also a ducted fan used *two* 30 kW engines, but barely flew out of the ground effect and was limited in speed. More powerful versions had other control problems.
Given the legal terror tactics employed by the MPAA and the RIAA, would it be possible to get both organizations labeled and subsequently banned as terrorist organizations?
have a lawyer draft an agreement that your employer accepts that reimbusring you for the laptop does not give them any rights whatsoever over your private data. Have your employer sign it before you accept the money.
Whatever you do, I'd advise you to keep your own and work data on separate partitions and encrypt both with different keys. Provide your employer only the key to unlock the partition with your work data. If you are running Linux, OS X or MS Windows you can use truecrypt.
If you are running Linux or *BSD and if you are feeling nasty, you can use one of the encryption schemes native to those systems. The chance that a typical windows-only IT department will ever figure out how to decrypt that are small IMHO, even with a key.
Gutmann's paper was based on 1990-era technology. And even then you didn't need all 35 passes, just the ones that correspond to the encoding used on the disk. If I read the enhanced version of the paper correctly, restoring even plainly overwritten data from a modern disk is a hopeless task.
If you read the enhanced version on his homepage, he says that he didn't update the paper because it is practically unfeasable to try and restore overwritten data from a modern disk. In the epilogue he says:
Any modern drive will most likely be a hopeless task, what with ultra-high densities and use of perpendicular recording I don't see how MFM would even get a usable image, and then the use of EPRML will mean that even if you could magically transfer some sort of image into a file, the ability to decode that to recover the original data would be quite challenging.
It depends on the dice being not biased, and the mechanics not exerting any influence.
One should test it by letting the machine rip for a couple of days, and then analyse the produced numbers for randomness, e.g. with the diehard test suite.
1) safeguard your data. The/home partition on my laptop is encrypted, so my data is inaccessible to others.
2) make the laptop unattractive to thieves Have your name and address engraved on several parts of the housing and lid. Or have some metal or plastic tags engraved and bond them securely to case and lid (or even to the screen). This will make the tags impossible to remove without replacing the case (or the lcd). This will make the laptop harder to resell.
Slashdot Mirror
When designing machinery or constructions, deflection under load is often the limiting factor. In those cases the stiffness of the construction is much more important than the strength of the material.
Now the stiffness of a construction is determined by both the shape and the material stiffness or Young's Modulus.
But AFAICT, little if any progress has been made in improving the Young's Modulus of alloys.
Additionally, often the ultimate strength of metals isn't really important in a design. In general designers want to make sure that the stresses in the material don't exceed the proportionality limit.
When the book came out, it was the first sci-fi book in years that I couldn't put down.
And the film stayed fairly true to the book, which is also uncommon.
Technically, you could say that the Martian is more *engineering*-fiction; it's not about discovering new principles, but making stuff work. Even in ways it was never meant to, and without the proper means. In that aspect is also great *hacking* fiction.
As an engineer myself I loved it. Especially the book. Stuff going wrong is very recognizable in engineering practice. Every experienced engineer has had their "oh, shit" moments.
Circa 1990. 368SX-16 through a discount program at school during my bachelor's. If memory serves, it had a 40 MB harddisk. Didn't buy a DX so I could buy a deskjet printer as well. Installed MS-DOS 5.0 when it came out. Looked at QBasic, but didn't like it. Mainly used it to run WordPerfect and Turbo Pascal and later Turbo C.
At school we used a 386DX to run NASTRAN on Xenix. That was my first contact with UNIX.
I upgraded components over the years until I had a 486 around 1994. Installed OS2 2.0. Used IBM's compiler, but it was buggy and expensive. Installed GCC and GNU Make. Then a friend showed me Linux.
It must have been in 1996 when I downloaded a dozen floppies worth of Slackware in the evenings using my modem, and dove right in. I've been using Linux and later FreeBSD ever since.
Good times. :-)
Their rocket blew up, they've been trying to find out why.
(Not uncommon in that business)
Is anybody surprised that this costs a lot of money?
Looking at the video frame by frame, it looks like the explosion starts between the rocket and the tower...
A fitting tribute! Thank you for sharing it.
And thank you Sir Terry, for your wonderful stories.
A flash website in 2013?
The problem with all these powered lift gizmos (like the Williams X-jet and the Hiller VZ-1) is that you tend to fall out ouf the sky when your engine fails... The Hiller VZ-1 which is also a ducted fan used *two* 30 kW engines, but barely flew out of the ground effect and was limited in speed. More powerful versions had other control problems.
Given the legal terror tactics employed by the MPAA and the RIAA, would it be possible to get both organizations labeled and subsequently banned as terrorist organizations?
I want a Dennis Ritchie day!
Second that. Dennis Ritchie's legacy is way more important.
Why is this even news?
Using the same "logic" they can't use Republic either, because it has republican in it.
If Apple is not the author of a work, are they allowed to impose additional terms on its usage and distribution?
IANAL, but I don't think so. That right is usually restricted to the owner of the copyright.
Professor Randy Pausch's last lecture.
This is a very interesting and moving lecture that he essentially put together for his children when he was dying of cancer.
I think the trailer looks pretty well for an animated movie made in a limited time and budget.
I think that you basically have two choices:
Whatever you do, I'd advise you to keep your own and work data on separate partitions and encrypt both with different keys. Provide your employer only the key to unlock the partition with your work data. If you are running Linux, OS X or MS Windows you can use truecrypt.
If you are running Linux or *BSD and if you are feeling nasty, you can use one of the encryption schemes native to those systems. The chance that a typical windows-only IT department will ever figure out how to decrypt that are small IMHO, even with a key.
Gutmann's paper was based on 1990-era technology. And even then you didn't need all 35 passes, just the ones that correspond to the encoding used on the disk. If I read the enhanced version of the paper correctly, restoring even plainly overwritten data from a modern disk is a hopeless task.
If you read the enhanced version on his homepage, he says that he didn't update the paper because it is practically unfeasable to try and restore overwritten data from a modern disk. In the epilogue he says:
The core of this invention seems to be that an on-screen keyboard with more space between the keys leads to less typing errors.
Well, duh!
<sarcasm>
I've got an "invention" too! (written in English, because I don't speak Patentese):
</sarcasm>
It depends on the dice being not biased, and the mechanics not exerting any influence.
One should test it by letting the machine rip for a couple of days, and then analyse the produced numbers for randomness, e.g. with the diehard test suite.
The trailer looks good.
Then why not go for a powered paraglider? In case of engine failure it has a decent glide ratio.
It is also much more efficient. A paraglider can fly with a 20 HP engine, instead of 200!
You can get a new powered paraglider for around US$ 8000 instead of US$100K.
Anyone remember Cairo? ;-)
If the engine dies, so do you.
1) safeguard your data. /home partition on my laptop is encrypted, so my data is inaccessible to others.
The
2) make the laptop unattractive to thieves
Have your name and address engraved on several parts of the housing and lid. Or have some metal or plastic tags engraved and bond them securely to case and lid (or even to the screen). This will make the tags impossible to remove without replacing the case (or the lcd). This will make the laptop harder to resell.