Microsoft may from time to time make available for download from the Services certain images, artwork, photographs, videos, and other content (the "Downloadable Content"). Microsoft hereby grants you a limited, non-transferable, nonexclusive license to download such content solely for your personal, noncommercial use in accordance with these Terms of Use. Such license shall be limited to the specific purpose for which such Downloadable Content was made available (e.g. for use as wallpaper or poster prints, as specified in connection with the download), and you may not modify, distribute, perform, transmit , create derivative works of or otherwise use such Downloadable Content or make any commercial or public use thereof. Downloadable Content shall only include content which Microsoft specifically identifies as being available for download, and you agree not to remove of obscure any copyright notice that appears in the Downloadable Content.
Note the words "Microsoft hereby grants you a limited, non-transferable, nonexclusive license to download such content solely for your personal, noncommercial use in accordance with these Terms of Use." Microsoft granted you a license. They didn't provide a provision which allows them to revoke that license. They don't have the option, once having sold you a license, to take it back. The FTC was out to lunch during the Bush Administration, but they're back in business.
The "battle bots" are mostly the usual stupid R/C "battery-motor-wheels" stuff. But some of the humanoid hobbyist robots on display are getting good. Dynamixel servos, which have useful feedback to the controller, are taking over. (They have a 1mb/sec polled serial link shared by all the servos. It's RS-485, which is 1970s technology, but that's progress over the usual one-way PWM interface.) The latest prototype Dynamixel servos can reach 500 degrees/sec, which means there's hope of making legged running work. Some of the humanoid robots have a 6DOF inertial unit, although balancing software is way below the Big Dog level and none of the humanoids had force-sensing feet.
The better hobbyist humanoids are almost at the hardware level at which Asimo/Big Dog performance becomes possible. The more advanced robot hobbyists now understand about ZMP. We're getting there.
For better coverage, see Robots-Dreams, which also covers the Japanese hobbyist robot scene.
Something is clearly wrong with their tower firmware and this is a *recent* problem. It worked flawlessly in these same spots until just a few months ago...
Happens every spring. Foliage is opaque to gigahertz RF.
The other big problem with the teaching of mathematics is the emphasis on "puzzles". That's all wrong. Mathematics is a tool for design and analysis of things you might want to build or understand. It should be taught that way. In particular, high school calculus and high school physics should be integrated. Teach calculus as a way to understand mechanical systems and electrical circuits, and it makes much more sense.
I have (somewhere) a U.S. Navy textbook from WWII which teaches calculus from exactly that standpoint. During WWII, the Navy needed engineering technicians in a hurry, and they set up a crash training program without much input from the "educational establishment".
I've done some rather math-heavy programming. I'm one of the people who made ragdoll physics work, a painful exercise in geometry, differential equations, and error control. (If you're not real serious about the error control, your ragdolls will fly apart or launch themselves into space for no reason visible to the end user. This gets you nasty writeups in game magazines.)
I've also done proof of correctness work, using and working on automatic theorem provers. And I've done some work on sensor fusion for inertial navigation systems.
Despite this, I've never had to do a classic high-school type geometric proof since high school. High school geometry is taught that way because Euclid taught it that way two millennia ago. (A century ago, schools were still using Euclid's Elements as a textbook.) It's only taught because it's locked into college entrance exams like the SAT.
If you want to teach mathematical reasoning, that's fine. But there's no reason to teach it in the geometric domain. It's a skill that's used very, very seldom.
Stanford had a very expensive conversion to PeopleSoft a few years ago. Stanford had a huge collection of in-house systems from the 1970s and 1980s, running on either DEC PDP-10 machines or IBM mainframes. They've finally phased out all the PDP-10 based stuff at Stanford proper, although SLAC is still running some PDP-10 code.
Those are mistakes an end user would see. Here are some deeper mistakes from an engineerings standpoint.
Bus-type peripheral architecture. The IBM PC was a spinoff of the IBM Displaywriter, a dedicated word processor with no expandability. It inherited some design decisions from the Displaywriter that were reasonable for a word processor, but terrible for an expandable machine. Most notably, the IBM PC had the peripherals on the memory bus. That meant any DMA had to be on the I/O card, and thus any card could blither all over memory. Peripherals were thus trusted devices, and, in turn, drivers had to be trusted. IBM knew the right answer - channels, as on mainframes, and in the PS/2, they used a "microchannel" architecture. But it was too late - the industry had already standardized on "ISA cards". This is the fundamental reason cause of most operating system crashes - the I/O architecture gives drivers too much power.
The Motorola MMU debacle.The Motorola 68000 first appeared in 1978, and it was a very good machine. Almost. There was a flaw. Instruction backout didn't quite work, and thus a paged MMU couldn't be added. So Motorola didn't ship an MMU with the 68000. The early UNIX workstations all used the 68000, and painful hacks were used to kludge together some kind of MMU to make it work. Apollo used two CPUs, one for the OS and one for the user, only one running at a time, to get around this. The Apple Lisa used one CPU with an Apple MMU built from many parts, and the compiler avoided generating any instructions with incrementation so that backout would work. Motorola came out with the M68010 in 1982, which fixed the bugs, but there was still no MMU. When Motorola finally shipped the 68451 MMU, it was a segmented MMU, and worse, slowed down the machine by one clock cycle per memory access. If Motorola had gotten it right by 1979 or so, the whole history of personal computing might have been Motorola-based using protected mode-UNIX.
The Intel 286 CPU. Not enough memory management for a protected mode OS, too much segmentation machinery for an unprotected OS. That powered the IBM PC/AT and a whole generation of machines with the addressing system from hell. It could run a version of UNIX, but no process could exceed 64K in protected mode, although you could put a few megabytes on the machine.
Baseband Ethernet. Coax-based Ethernet had some serious electrical problems. The thing really was unbalanced baseband, so you couldn't use capacitive coupling. The coax shield could only be grounded at one point, or you'd get ground loops. That created an electrical safety issue with the outside of coax connectors, and running coax between buildings was iffy. It was just bad electrical design. 10baseT, which is balanced, was far better from an electronics standpoint.
When you try the blind search test, the results look very similar. All the mainstream search engines are doing about equally well. There was a period in 2007 when Yahoo was substantially ahead of the others, because they had about fifty special-case recognizers for things like celebrities and movies, but now everybody has that. (And nobody noticed that Yahoo was better for the six months they had a technical edge, anyway.)
Try heavily-spammed searches like "London hotels". All the big guys are still being fooled by ad-heavy redirector sites. It's possible to do better against link spammers, but the big guys aren't trying very hard to do so. Google used to be against "search engine optimization", but some time in 2007 they went over to the dark side and started sponsoring SEO conferences. It's inevitable; Google makes their money from AdWords. Search is just a traffic builder.
The Iranian people will have to rise up and displace their government, by force if necessary.
Been there, done that. That's how we got the present situation. In 1979, Islamic militants overthrew the 2500 year old monarchy. Before, they had an oppressive right-wing monarchy.
Now, they have an oppressive Islamic theocracy.
But we both know they're all noise to cover the same ol' non-stop war for power between two kinds of creep, who keep reappearing in Mexican history under different names: the "charismatic guerrilla" leader like Villa and Zapata, who always turn into sleazy dictators once they get power, and the plain old rich landlord elite, who start out as sleazy dictators and so don't have to pretend they're anything else from the get-go. If you live anywhere in the tropics, let's face it: those are your choices, always have been and always will be. Don't blame me, I just work here. - "Gary Bretcher", the "War Nerd".
Many people have. That's why there are so many Iranian businessmen in the US. But it's harder to get into the US now.
Before Iran had an Islamic theocracy, Iran had a brutal (but pro-US) right-wing dictator, Shah Mohammad Reza Pahlavi. Iran had 2,500 years of monarchy before the Islamic revolution in 1979. Iran has never had anything like a democracy.
Probably a bad idea. This is known in the military as the "Great Squad Leader in the Sky" syndrome (a phrase coined by David Hackworth, one of the greats of small-unit combat), and has been since Vietnam. Leadership from a helicopter overlooking a combat zone sounded like a great idea; at last, the commander could see everything. In practice, it works very badly.
Piping vast amounts of imagery back to a command center is popular with commanders and politicians, but not with grunts. It's useful for finding enemy activity, but not much help once the enemy has been engaged.
It turns out that the technology the people on the ground really like is small robots. Sending in a robot first in urban warfare is very popular with the troops. Nobody likes going into a possible ambush or booby trap several times a day. Eventually the odds catch up with you.
Mod parent up. Most of this is already standard, and mandated by the FCC. The new stuff is just some iPhone-specific problems that Apple has to deal with. All the nonessential guck in the phone needs to be switched off during emergency calls.
911 calls have at least the following FCC-mandated features.
Billing problems must be bypassed. 911 calls must go through even if the cell phone has no account, the billing system is down, the phone is roaming out of area, or the local provider can't contact the home provider for billing passthrough.
Transmit power management is disabled. Cell phones go to full power in emergency mode. (Yes, battery drain goes up.)
If the phone cannot connect to a cell site of its own system, after 17 seconds it must try to connect to any cell site of any system it can reach. Phones used to fall over to analog roam when necessary, before analog AMPS went down.
GPS information is transmitted.
A higher QoS is specified within the cell phone network, so emergency calls get in ahead of non-emergency traffic.
The call is not easily disconnected until the emergency operator releases it, although there's usually some way to force disconnect from the cell phone end.
It's not like Apple just invented "emergency mode".
What worries me is an attack that takes Wall Street down for three weeks. When it comes back up, the US will no longer be the financial center of the world. Singapore, Beijing, and Dubai will have taken up the load.
That wasn't possible in 2001, by the way; the other trading centers didn't have the capacity or the capital backing. Now they do.
Then again, Beijing is going to displace New York within a decade anyway. The US is now a debtor nation, and trading moves away from debtor nations.
Lee Smolin, the physicist, writes that "Smart people should not program". He used to program, and at one point insisted that his department continue to teach physics students programming. But then he realized that the needed functionality was either available off the shelf or could be written by lower level people. So he now recommends against wasting students' time on programming.
This isn't likely to work for anything that needs to be architected, or is at all complex.
What you're going to get, at best, is a collection of un-integrated features in search of a design. Of course, for some applications, that's good enough.
PyPy, the Python implementation written in Python, was developed in big "sprints". Six years on, it still doesn't work well enough to be used for anything.
There are too many bad programmers out there for "crowdsourcing" to work well. I put a moderately simple job on Rent-A-Coder once - I wanted an open source Python program to read WHOIS data from any registrars. This requires a tiny module for each registrar, and after writing a few myself I decided to outsource the next hundred registrar-specific modules. Four "Rent-A-Coder" programmers failed on that job.
The next generation of military robots
on
Wired for War
·
· Score: 1
(Wasn't this book reviewed once before on Slashdot?)
That book is all about the previous generation of military robots. Take a look at the
next generation:
The Legged Squad Support System. This is the next generation of "Big Dog" - fully militarized, no more annoying two-cycle engine noise, stronger, faster, more range, about the same size. This isn't even considered a research project; it's on the weapons deployment track.
The Multi-Robot Pursuit System. Packs of robots to hunt down uncooperative humans. Your tax dollars at work.
Wait until China starts cranking out these things by the millions.
Print media sometimes drops to Twitter level
on
One-Tweet Wonders
·
· Score: 1
At least there's a length limit on Twitter.
Yesterday, this article by Jon Caroll appeared in the San Francisco Chronicle. This guy is a paid columnist.
He wrote about forty column-inches about taking his car to a car wash. Nothing exciting happened; he just washed his car. This is how far down the print media have come.
The Chronicle is considering shutting down their print version. This guy may not have much of a career left.
Disney used to have an official "crap sequels division", called "Disneytoons". Disneytoons was responsible for Sleeping Beauty 2, Mulan 2, Jungle Book 2, etc., direct-to DVD efforts designed to wring the last dollar out of each franchise. When Disney bought Pixar, Disneytoons was shut down. This was just as well. Sequels from Disneytoons were far, far worse than the originals.
It looks like Pixar is being given Disneytoons' job. "Cars 2" is being made because about $5 billion in "Cars" merchandise has been sold, and with another Cars movie, another few million tons of injection-molded plastic can be shipped out. There's no other reason for another "Cars" movie; the story was complete in itself.
Apparently they're not doing another "Incredibles" movie. That concept has more franchise potential than "Cars". But it wouldn't move the injection-molded plastic.
Right. NASA didn't do much in the semiconductor area. The USAF put tons of money into basic research into transistors and ICs, but not NASA. (I still remember the whining from the Air Force types in the 1980s, when the commercial market finally pulled ahead of the military one.)
NASA sometimes takes credit for Teflon, but that was a spinoff of the Manhattan Project, which needed a sealant resistant to uranium hexafluoride.
NASTRAN, the finite-element analysis program, is considered perhaps the most useful spinoff of the space program.
That's a great article by William Langewiesche. Note that he makes the point that Flight 1549 was able to make a smooth engines-out landing in the Hudson because the flight control computers were helping all the way to the water. The computers kept the aircraft just above stall (which is very tough with no engine power) and allowed a slow descent and a slow landing speed (which are competing goals for an aircraft).
The people who have nothing to say are all on Facebook now. The remaining blogs are typically either from people who are serious writers, or those who simply need a place to post operational info like software updates.
That's been tried many times, especially in concurrent FORTRAN variants. The problem is that it doesn't help with locking and interlocking unless the compiler is able to determine that "parallel" tasks really are independent. In some number-crunching applications, that's possible. If the "parallel" tasks are allowed to have any access to shared data, more structure is needed in the program.
It's easy to say that you want something done in parallel. The problem is detecting race conditions, providing the locking necessary to deal with them, and figuring out the invariants of the shared data.
Many, many ideas have been tried in this area. Most of them break down when there's a need for complex interaction between threads, as in a window system, browser, or MMORPG server. Partitioning of problems like inverting big matrices in parallel is well understood. But that's not why most people get multi-core CPUs today.
Slashdot Mirror
All I could see when I read that was the big honking word "LIMITED".
Limited to time? Sure. Availability? Why not!
Because ambiguity in a contract is construed against the drafter of the contract. Provided you meet the limits explicitly specified ("personal, noncommercial use") you can do anything you want with the content, and Microsoft is barred from imposing further restrictions after the fact.
Microsoft seems to be violating their own Zune EULA:
Microsoft may from time to time make available for download from the Services certain images, artwork, photographs, videos, and other content (the "Downloadable Content"). Microsoft hereby grants you a limited, non-transferable, nonexclusive license to download such content solely for your personal, noncommercial use in accordance with these Terms of Use. Such license shall be limited to the specific purpose for which such Downloadable Content was made available (e.g. for use as wallpaper or poster prints, as specified in connection with the download), and you may not modify, distribute, perform, transmit , create derivative works of or otherwise use such Downloadable Content or make any commercial or public use thereof. Downloadable Content shall only include content which Microsoft specifically identifies as being available for download, and you agree not to remove of obscure any copyright notice that appears in the Downloadable Content.
Note the words "Microsoft hereby grants you a limited, non-transferable, nonexclusive license to download such content solely for your personal, noncommercial use in accordance with these Terms of Use." Microsoft granted you a license. They didn't provide a provision which allows them to revoke that license. They don't have the option, once having sold you a license, to take it back. The FTC was out to lunch during the Bush Administration, but they're back in business.
So if you have a Zune, and it won't play something you paid for, go to the Federal Trade Commission online complaint page and start filling out the form.
The FTC was out to lunch during the Bush Administration years, but that's over. They're back in business.
The "battle bots" are mostly the usual stupid R/C "battery-motor-wheels" stuff. But some of the humanoid hobbyist robots on display are getting good. Dynamixel servos, which have useful feedback to the controller, are taking over. (They have a 1mb/sec polled serial link shared by all the servos. It's RS-485, which is 1970s technology, but that's progress over the usual one-way PWM interface.) The latest prototype Dynamixel servos can reach 500 degrees/sec, which means there's hope of making legged running work. Some of the humanoid robots have a 6DOF inertial unit, although balancing software is way below the Big Dog level and none of the humanoids had force-sensing feet.
The better hobbyist humanoids are almost at the hardware level at which Asimo/Big Dog performance becomes possible. The more advanced robot hobbyists now understand about ZMP. We're getting there.
For better coverage, see Robots-Dreams, which also covers the Japanese hobbyist robot scene.
Something is clearly wrong with their tower firmware and this is a *recent* problem. It worked flawlessly in these same spots until just a few months ago...
Happens every spring. Foliage is opaque to gigahertz RF.
The other big problem with the teaching of mathematics is the emphasis on "puzzles". That's all wrong. Mathematics is a tool for design and analysis of things you might want to build or understand. It should be taught that way. In particular, high school calculus and high school physics should be integrated. Teach calculus as a way to understand mechanical systems and electrical circuits, and it makes much more sense.
I have (somewhere) a U.S. Navy textbook from WWII which teaches calculus from exactly that standpoint. During WWII, the Navy needed engineering technicians in a hurry, and they set up a crash training program without much input from the "educational establishment".
I've done some rather math-heavy programming. I'm one of the people who made ragdoll physics work, a painful exercise in geometry, differential equations, and error control. (If you're not real serious about the error control, your ragdolls will fly apart or launch themselves into space for no reason visible to the end user. This gets you nasty writeups in game magazines.)
I've also done proof of correctness work, using and working on automatic theorem provers. And I've done some work on sensor fusion for inertial navigation systems.
Despite this, I've never had to do a classic high-school type geometric proof since high school. High school geometry is taught that way because Euclid taught it that way two millennia ago. (A century ago, schools were still using Euclid's Elements as a textbook.) It's only taught because it's locked into college entrance exams like the SAT.
If you want to teach mathematical reasoning, that's fine. But there's no reason to teach it in the geometric domain. It's a skill that's used very, very seldom.
Stanford had a very expensive conversion to PeopleSoft a few years ago. Stanford had a huge collection of in-house systems from the 1970s and 1980s, running on either DEC PDP-10 machines or IBM mainframes. They've finally phased out all the PDP-10 based stuff at Stanford proper, although SLAC is still running some PDP-10 code.
This is a good reason to block all ad sites at your corporate firewall. You'll probably cut your Internet bandwidth usage in half, too.
Those are mistakes an end user would see. Here are some deeper mistakes from an engineerings standpoint.
When you try the blind search test, the results look very similar. All the mainstream search engines are doing about equally well. There was a period in 2007 when Yahoo was substantially ahead of the others, because they had about fifty special-case recognizers for things like celebrities and movies, but now everybody has that. (And nobody noticed that Yahoo was better for the six months they had a technical edge, anyway.)
Try heavily-spammed searches like "London hotels". All the big guys are still being fooled by ad-heavy redirector sites. It's possible to do better against link spammers, but the big guys aren't trying very hard to do so. Google used to be against "search engine optimization", but some time in 2007 they went over to the dark side and started sponsoring SEO conferences. It's inevitable; Google makes their money from AdWords. Search is just a traffic builder.
The Iranian people will have to rise up and displace their government, by force if necessary.
Been there, done that. That's how we got the present situation. In 1979, Islamic militants overthrew the 2500 year old monarchy. Before, they had an oppressive right-wing monarchy. Now, they have an oppressive Islamic theocracy.
But we both know they're all noise to cover the same ol' non-stop war for power between two kinds of creep, who keep reappearing in Mexican history under different names: the "charismatic guerrilla" leader like Villa and Zapata, who always turn into sleazy dictators once they get power, and the plain old rich landlord elite, who start out as sleazy dictators and so don't have to pretend they're anything else from the get-go. If you live anywhere in the tropics, let's face it: those are your choices, always have been and always will be. Don't blame me, I just work here. - "Gary Bretcher", the "War Nerd".
Leave. Now. While you still can.
Many people have. That's why there are so many Iranian businessmen in the US. But it's harder to get into the US now.
Before Iran had an Islamic theocracy, Iran had a brutal (but pro-US) right-wing dictator, Shah Mohammad Reza Pahlavi. Iran had 2,500 years of monarchy before the Islamic revolution in 1979. Iran has never had anything like a democracy.
Probably a bad idea. This is known in the military as the "Great Squad Leader in the Sky" syndrome (a phrase coined by David Hackworth, one of the greats of small-unit combat), and has been since Vietnam. Leadership from a helicopter overlooking a combat zone sounded like a great idea; at last, the commander could see everything. In practice, it works very badly.
Piping vast amounts of imagery back to a command center is popular with commanders and politicians, but not with grunts. It's useful for finding enemy activity, but not much help once the enemy has been engaged.
It turns out that the technology the people on the ground really like is small robots. Sending in a robot first in urban warfare is very popular with the troops. Nobody likes going into a possible ambush or booby trap several times a day. Eventually the odds catch up with you.
Mod parent up. Most of this is already standard, and mandated by the FCC. The new stuff is just some iPhone-specific problems that Apple has to deal with. All the nonessential guck in the phone needs to be switched off during emergency calls.
911 calls have at least the following FCC-mandated features.
It's not like Apple just invented "emergency mode".
they can take my SD CRT television when they pry it from my cold, dead hands.
So be it. After midnight tonight, it will never work again.
What worries me is an attack that takes Wall Street down for three weeks. When it comes back up, the US will no longer be the financial center of the world. Singapore, Beijing, and Dubai will have taken up the load.
That wasn't possible in 2001, by the way; the other trading centers didn't have the capacity or the capital backing. Now they do.
Then again, Beijing is going to displace New York within a decade anyway. The US is now a debtor nation, and trading moves away from debtor nations.
Lee Smolin, the physicist, writes that "Smart people should not program". He used to program, and at one point insisted that his department continue to teach physics students programming. But then he realized that the needed functionality was either available off the shelf or could be written by lower level people. So he now recommends against wasting students' time on programming.
This isn't likely to work for anything that needs to be architected, or is at all complex. What you're going to get, at best, is a collection of un-integrated features in search of a design. Of course, for some applications, that's good enough.
PyPy, the Python implementation written in Python, was developed in big "sprints". Six years on, it still doesn't work well enough to be used for anything.
There are too many bad programmers out there for "crowdsourcing" to work well. I put a moderately simple job on Rent-A-Coder once - I wanted an open source Python program to read WHOIS data from any registrars. This requires a tiny module for each registrar, and after writing a few myself I decided to outsource the next hundred registrar-specific modules. Four "Rent-A-Coder" programmers failed on that job.
(Wasn't this book reviewed once before on Slashdot?)
That book is all about the previous generation of military robots. Take a look at the next generation:
Wait until China starts cranking out these things by the millions.
At least there's a length limit on Twitter.
Yesterday, this article by Jon Caroll appeared in the San Francisco Chronicle. This guy is a paid columnist. He wrote about forty column-inches about taking his car to a car wash. Nothing exciting happened; he just washed his car. This is how far down the print media have come.
The Chronicle is considering shutting down their print version. This guy may not have much of a career left.
Disney used to have an official "crap sequels division", called "Disneytoons". Disneytoons was responsible for Sleeping Beauty 2, Mulan 2, Jungle Book 2, etc., direct-to DVD efforts designed to wring the last dollar out of each franchise. When Disney bought Pixar, Disneytoons was shut down. This was just as well. Sequels from Disneytoons were far, far worse than the originals.
It looks like Pixar is being given Disneytoons' job. "Cars 2" is being made because about $5 billion in "Cars" merchandise has been sold, and with another Cars movie, another few million tons of injection-molded plastic can be shipped out. There's no other reason for another "Cars" movie; the story was complete in itself.
Apparently they're not doing another "Incredibles" movie. That concept has more franchise potential than "Cars". But it wouldn't move the injection-molded plastic.
Right. NASA didn't do much in the semiconductor area. The USAF put tons of money into basic research into transistors and ICs, but not NASA. (I still remember the whining from the Air Force types in the 1980s, when the commercial market finally pulled ahead of the military one.)
NASA sometimes takes credit for Teflon, but that was a spinoff of the Manhattan Project, which needed a sealant resistant to uranium hexafluoride.
NASTRAN, the finite-element analysis program, is considered perhaps the most useful spinoff of the space program.
That's a great article by William Langewiesche. Note that he makes the point that Flight 1549 was able to make a smooth engines-out landing in the Hudson because the flight control computers were helping all the way to the water. The computers kept the aircraft just above stall (which is very tough with no engine power) and allowed a slow descent and a slow landing speed (which are competing goals for an aircraft).
The people who have nothing to say are all on Facebook now. The remaining blogs are typically either from people who are serious writers, or those who simply need a place to post operational info like software updates.
And the, of course, there's Twitter.
sequential as opposed to parallel
That's been tried many times, especially in concurrent FORTRAN variants. The problem is that it doesn't help with locking and interlocking unless the compiler is able to determine that "parallel" tasks really are independent. In some number-crunching applications, that's possible. If the "parallel" tasks are allowed to have any access to shared data, more structure is needed in the program. It's easy to say that you want something done in parallel. The problem is detecting race conditions, providing the locking necessary to deal with them, and figuring out the invariants of the shared data.
Many, many ideas have been tried in this area. Most of them break down when there's a need for complex interaction between threads, as in a window system, browser, or MMORPG server. Partitioning of problems like inverting big matrices in parallel is well understood. But that's not why most people get multi-core CPUs today.