This design will likely have higher drag than traditional supersonic aircraft. The designers cannot get around the fact that the air cannot move out of the way as quickly as the oucoming aircraft passes through it. Its just that instead of all the air piling up into a massive shockwave, it is distributed into a more gradual shock front that will be less perceptible.
The supersonic area rule tells designers how to minimize drag by shaping the profile of cross-sections (creating the right curve to the cross-sectional area). By inference, this invention does not minimize drag because it uses a different-from-optimal profile of cross-sectional areas. High drag = high fuel consumption and that will limit it's application to non-military aircraft.
I noticed a product called ThermaCare that uses an air-iron exothermic reaction to create a single-use heating pad. The description of the ingredients at ThermaCare's FAQ suggests some interesting and bad consequences of iron oxidation reactions. These include:
- the potential for generating uncontrolled levels of heat depending on the mix of iron, air, and accelerants.
- the potential for generating explosive hydrogen gas (in forming iron oxide from iron and water, hydrogen is left over).
Nanoscale iron reactions may well detoxify many pollutants. But high heat generation could volatilize solvents and explosions in and around contaminated soil don't seem wise either. I assume that some test samples would ensure that the soil was not too aerobic so that heat and hydrogen generation would be sufficiently gradual to forestall a dangerous reaction, but testing will always be imperfect.
The key to Apple's design is to:
- lower the RPM of each fan,
- lower the air flow velocity,
- lower the total CFM required by all fans, and
- reduce the turbulence of the airflow.
A single fan design has the disadvantage of having to move enough air to cover the worst case configuration of internal components and thermal loading -- ensuring that some air gets to every nook and cranny. With 9 fans in 4 thermal zones, each zone of the G5 is regulated to minimize fan speed whilst maintaining acceptable temperatures. More fans for more fan cross-sectional area also reduces noise. A single fan design requires higher velocities on the blades and airflow and creates more turbulent airflow. Thus, for example, blowing 24 CFM though a single 120 mm fan makes more noise that blowing the same 24 CFM through an array of three 90 mm fans.
The front and back mesh covers act as a acoustic diffusers and help create laminar flow (which is less noisy than turbulent flow). Finally, the flow-through design creates a uniform convective flow over the components versus other designs with more convoluted airflows that create uneven flow or dead-air zones in the case.
I guess causing a power outage is the hackerish way to test a UPS for proper operation. Its "better" than pusghing the test button or pulling the plug on the UPS itself because it ensures that you did not forget to plug the wall wart for the router into the UPS. It also simultaneously tests all the UPSes (UPI???) in the house/office. It will also tell you if your local internet connection (be it modem, DSL, cable, someone else's Wifi net, etc.) is dependent on the local grid.
It seems to me the that real problem is inadequate transmission capacity coupled with sky-rocketing demand. Everyone wants to turn on their air conditioner and power-hungry PCs, but nobody wants to have a power line in their backyard. Throw in parochial state utility regulatory boards, half-hearted attempts at deregulation, clueless execs at utilities, and Enron and you have the makings of a bigger mess than even Microsoft can create.
Its too bad we can't just double the clock rate on the power line and transmit twice as much power. Twice the clock rate = twice as fast = twice the power??? OK, so it doesn't work like that -- but then I never understood how those tiny little electrons could go through solid metal anyhow.
Yes, the emate is a very nice machine and makes my point again. The emate is another example of "obsolete" hardware besting newer products. But the emate is not pocket-sized like the Psion or Zaurus
I can only hope that some future PDA will be both truely portable and truely usable. I fear the current penchant for full compatibility with MS Bloatware means that PDA makers will continue to shoehorn hot, power hungry processors into their machines. Why does a PDA need a 400 MHz processor??? So it can display some crappy, useless Flash animation???
Another nice clamshell, too bad its worse than the 3-year-old Psion 5mx. How come nobody can make a PDA with:
- A decent keyboard
- A screen you can see in full sunlight
- Battery life of at least 20 hours (my 5mx regularly gets 30+ hrs)
- A light set of applications for basic office work?
I'm not saying the Psion 5mx is perfect, but you would think that with all the miracles of modern technology that someone could have made a device at least as good. Maybe Moore's Law is being bested by Gate's Law -- new products must have every feature imaginable, even if that makes no feature actually usable.
Patented = Published = DCMA Unconstitutional?
on
Cracking GSM
·
· Score: 4, Interesting
If this cracking method is indeed patented then it must be publicly released for anyone to read and understand. But public release would seem to violate DCMA and stifling the publication would seem to violate the constitutional underpinnings of the patent system (to encourage innovation by both granting monopolies and making inventions publicly accessible for further innovation). Does this make DCMA unconstitutional???
Confusing Science vs. Engineering vs. Adoption
on
What's Always Next?
·
· Score: 2, Insightful
Articles like these always confuse the role of science in society -- anything futuristic or techie is lumped under the rubric of science. Yet science really has so little to do with any of this. Scientists discover the laws, engineers develop products that make use of the laws, and businesses/governments/consumers invest in those products to adopt the fruits of the laws.
Science was done with the laws that underpin videophones, moving sidewalks, and fly cars several decades ago -- how many articles on flying cars make it into scholarly science journals these days? Engineers have been using those laws to make prototypes of the products or (more importantly) low cost approaches to manufacturing and deploying these products for quite a while.
Its the people that invest and adopt that hold up most "scientific" inventions long after science to done with the topic. Until the product is cheap enough and perceived as useful enough, all the science and engineering in the world is irrelevant. This is where marketing to cosnumers or lobbying to governments comes into play.
I don't know why people think games need to work at becoming more mainstream. Games and movies offer very different styles of entertainment to match the different moods of different people. Sometimes some people want passive entertainment -- a vicarious thrill, an interesting plot, some nice characters, or just some pleasing scenery or special effects. Sometimes some people want active entertainment -- a tough mental puzzle, intense competition, a world you can put yourself into, or just a chance to open up a big can of whoopass on some monsters.
The notion that games should be more like moves or movies should be more like games is not necessarily going to increase marketshare. Trying to merge the two is just another example of going for the lowest common denominator.
Leaving aside the humorous notion of a plurality of betas, the existence of betas and technology demos are no gaurantee that the project is not getting out of hand. Multiple major slippages of the schedule are a really bad sign. And if the time between versions grows too large, the development team spends too much of the latter part of the effort fixing the obsolete parts created in the early part of the effort.
Also, betas and demos are no substitute for widespread adoption and usage of the OS because the people that look at betas & demos are markedly different from the mainstream computer-using public. Being wrapped in a cocoon of its own coders and developer devotees is likely to create code that is geek-approved and user-hated. Four years between OS versions is a long way to go without true feedback from the average user.
I'm not necessarily saying that MS does not know what they are doing or that they don't have good reasons for changing the release date. They just need to be careful that Longhorn does not turn into something like Apple's Copland.
The problem is that the actual person may also have a really tough time reproducing the same speeds, patterns, etc. in their signature.
That is the entire point of a modal analysis of the signature. It captures not only the central tendency of the signature, but also the characteristic modes of variation. The idea is that everyone's signature varies in amounts and ways that are unique to that person. Some people might vary more on the first letter, the heights of letters, the shapes of loops, slant, the spacing where the hand scoots over, etc. Analyzing a population of samples from the person gives the system a good idea about what parts of the signature vary, how they vary, and how much they vary.
The reasons for this are especially apparent when you look at the handwriting of people like myself whose fine motor control (like many guys) is not so "fine"
Like you, I too was born without an analog plotter interface. A person like myself or jtheory will simply get logged by the system as being more variable than a person like Ms. Ima Caligrapher. If a forger or mouselogger tries to replicate our signature, they will be flagged as being too perfect.
Obviously if someonce can log the mouse motions with an accurate timestamp, then they can replicate the signature. But then EVERY computer-connected biometric ID system is potentially susceptable to interception/replay of the biometric key signal.
In the case of this system, an arms race between the forger/loggers and the ID systems company would then ensue. The first countermeasure to mouse-loggers would be rejection of identical traces (as others have suggested). To this forgers would add statistical noise to the trace. The ID company would then need to create a more sophisticated statistical test that rejects traces that did not vary enough while staying within the statistical bounds of the 20 training samples that the systems asks for. An SVD on some transform of the sample signatures would help uncover both the strongest and weakest modes of variation. Signatures that did not match on the main pattern and did not vary sufficiently in expected way would be rejected. This would prevent either direct play-back or a simplistic addition of noise to the mouse trace.
The presence of both a predicable static pattern (the "average" signature) and modes of variation (because people don't actually sign their name identically to the nanometer/nanosecond) makes this biometric key better than other more invariant biometric features that can be copied.
This looks like a variation on what the folks at Cybersign do. Their technology is based on matching the dynamical pattern of motion, not just the X-Y coordinate trace. A forger would have a hard time copying the variations in speed that the actual person uses even if the forger traces the same path or tries to "get good" at the signature.
Longhorn sounds like an OS development effort that is spinning out of control. Microsoft could always copy the strategy that Apple used when Apple's Copland effort blew up in 1996 -- buy a company with a Unix-based OS and switch everyone to that.
Should Microsoft call it Visual Linux#.NET or OS XP?
With a good high-gain antenna, they should be able to access wireless LANs for quite a distance. Were I in the vicinty, I would be honored to have them posting their progress through my network.
Yes and no. Fatigue WAS a major issue in the early years of aviation, but now it is well understood. As long as you have a proper understanding of the material's properties and the stresses induced by the application, then you can design to forestall or eliminate fatigue cracking. Some materials (certain types of steel) actually have infinite fatigue resistance as long as the stresses are below a critical threshold. Stress cracks are not an issue where one can employ a combination of good design, good "life" testing, good operator training, and good inspection/maintenance procedures. I'm not saying that bad things can't happen, just that they are preventable.
Ornithopters do and will work. Materials fatigue, control issues, mechanical design, aerodynamic optimization are are solvable problems. Flapping flight exploits some important aerodynamic properties that provide much higher lift than is possible with fixed wings with steady-flow. Unsteady flow aerodynamics explains the very successful flight abilities of the Bumblebee, despite the assumption-laden proofs against this fuzzy little nectar collecter.
But whether ornithopers will ever carry humans in any quantity is doubtful because the ride will, to say the least, be sickeningly bumpy. The unsteady flows over the flapping wings mean cyclic forces on the fuselage and cyclic accelerations for the passengers. The ride will be much much worse than that of a helicopter and more like the ride in a small boat riding a very rough swell. Other flapping organism don't mind the vibration and cyclic motion of flight as they are evolved to tolerate it. In contrast the human propioception system will definitely hurl when subjected to the "graceful" up and down motion of a large-scale flapping machine.
Ornithopters will make really cool recon drones, whether over battlefields or Mars, but they will make horrible passenger vehicles
Newer news was is Science News in August 9, 2003 in "Electric Foam" (sorry, I don't have a link to the full text). Its a way to make piezoelectric polypropylene foam. Although the material needs more development (it losses its piezoelectric properties at temperatures that might occur in a car glove box), the new foam could expand the use piezoelectric materials in consumer products.
Cool. I know that the CNAPs chip actually had 80 transputers per chip, of which only 64 would be enabled.
It seems to me that a relatively dense, but semirregular interconnect architecture would provide the greatest flexibility for morphing the TRIPS grid to both handle different types of code and to route around internal damage. Admittedly, more complex physical topologies raise the cost of dynamically optimising the logical topology. Have you ever looked into notions like Golumb rulers to set the physical interconnection design?
If you delve further into the project ( http://www.cs.utexas.edu/users/cart/trips/ ) then you will see that the problem of latency is the #1 motivation for the project. TRIPs appraoch to reconfiguring a grid of ALUs should help it maximize utilization. Even so, I doubt that TRIPs is a panacea because so many software problems feature patterns of execution that are undecidable without access to a large space of memory (thus the desire for huge high-speed caches). Yet a more flexible, configurable set of ALU cores and interconnecting pipes might let a computer rebalance itself for maximum performance on a wide range of different tasks including (in their words) workloads as diverse as control-bound integer codes, highly parallel threaded codes, and regular, computationally intensive streaming codes. This ability to perform well, not perfectly, on a wide range of tasks should help the design deliver good performance on mixed and variable environments such as desktop computing and complex database-driven webserving applications. Certainly, TRIPs should be superior to the more rigidly fixed designs of current CPUs or the modestly flexible VLIW-like architecture embodied in Itanium.
Those that think that multiple cores on a single die mean low yields are assuming that each core must be a multi-million transistor monstrosity like those in current desktop CPUs. They forget that you can create a useful CPU in under 100,000 transistors (e.g., the 68000). Indeed I know of one company, back in the early 90s, that sold a parallel processing board that contained 64 simple, operational transputer cores per chip(CNAPS 1064-64). Moreover, the morphware concept in TRIPs should be able to handle some density of defects in the grid of cores, including end-of-life failures, by remapping the processor net to route around dead/dying ALUs.
When I first saw this topic I chuckled -- yes the Internet is declining in quality, but it does not seem so bad. Then I went to do a quick search for what I partially remember about an old toy from my youth. A nice specific 6-term search on Google yielded a manageable 238 hits. So then I started looking at the hits.
GRRR! 80-90% of the hits where those odious faked search hit pages that spew a bunch of popular words on a page while trying to get you to come to some e-commerce site. They claim to be "Product Comparison" sites. But its gets worse than that. They all had names with 3 patterns: a fruit theme (e.g. cherryblossom, plumwind, etc.) a street/weather theme (e.g, foggyavenue, windyexpressway, etc.); or a named couple theme (samanddiane, jenniferandvictor, etc.) all prefixed with a variety subdomains like "www" "info" etc. But its gets worse than that. I visited one of the pages and found a long list of links that simply crosslink to other sites in this little corner of e-commerce hell.
So, we have an entire corner of the internet that was probably generated in software -- a cute little combinatorial program that generates a bunch of domain names and a set of heavily cross-linked webpages that are assured of getting a high rank in Google. If someone ever shuts it down, the owner only need hit the "run" button to recreate the entire web of sites.
The real problem with the Internet is that everything is too cheap and easy. It is too cheap and easy for spammers to churn out e-mail messages, too cheap and easy for e-commerce sites to combinatorially generate a thousand domain names and cross-linked site pages.
When the cost of creating and distributing information is zero, the bulk of that information is worth zero. Meanwhile the cost to the recipient climbs without bounds. So paradoxically, the low cost of the internet will mean the death of the internet.
If Symantec, M$, et al really care about consumers, then they should change when consumer's credit cards are charged for buying the product. If the box and CD are useless until product activation, then consumers should not have to pay until they have successfully run the activation procedure.
I have nothing against antipiracy/product activation per se. But I do object to schemes that force people to pay up front and then jump through a series of hoops that have a non-zero probability of failure. Until a company delivers value, it should not expect consumers to deliver payment.
Point taken. As long as current is flowing through a voltage drop, there are I^2R losses.
Perhaps the problem is that we are both right. One the one hand, a fast-switch would reduce the I^2R losses through the junction during the switch from near infinite impedences to neear-zero impedance. It is true that these losses would drop with increasing speed in the semiconductor. One the other hand, losses from charging/discharging junction and trace capacitance would be still be proportional to clock-speed. So which dominates in CPUs of today? And what really limits the clockspeed in complex digital circuits -- the on-off transition time of the gate or the R/C time constant into the fan-out of the downstream junctions?
Slashdot Mirror
This design will likely have higher drag than traditional supersonic aircraft. The designers cannot get around the fact that the air cannot move out of the way as quickly as the oucoming aircraft passes through it. Its just that instead of all the air piling up into a massive shockwave, it is distributed into a more gradual shock front that will be less perceptible.
The supersonic area rule tells designers how to minimize drag by shaping the profile of cross-sections (creating the right curve to the cross-sectional area). By inference, this invention does not minimize drag because it uses a different-from-optimal profile of cross-sectional areas. High drag = high fuel consumption and that will limit it's application to non-military aircraft.
I noticed a product called ThermaCare that uses an air-iron exothermic reaction to create a single-use heating pad. The description of the ingredients at ThermaCare's FAQ suggests some interesting and bad consequences of iron oxidation reactions. These include:
- the potential for generating uncontrolled levels of heat depending on the mix of iron, air, and accelerants.
- the potential for generating explosive hydrogen gas (in forming iron oxide from iron and water, hydrogen is left over).
Nanoscale iron reactions may well detoxify many pollutants. But high heat generation could volatilize solvents and explosions in and around contaminated soil don't seem wise either. I assume that some test samples would ensure that the soil was not too aerobic so that heat and hydrogen generation would be sufficiently gradual to forestall a dangerous reaction, but testing will always be imperfect.
The key to Apple's design is to:
- lower the RPM of each fan,
- lower the air flow velocity,
- lower the total CFM required by all fans, and
- reduce the turbulence of the airflow.
A single fan design has the disadvantage of having to move enough air to cover the worst case configuration of internal components and thermal loading -- ensuring that some air gets to every nook and cranny. With 9 fans in 4 thermal zones, each zone of the G5 is regulated to minimize fan speed whilst maintaining acceptable temperatures. More fans for more fan cross-sectional area also reduces noise. A single fan design requires higher velocities on the blades and airflow and creates more turbulent airflow. Thus, for example, blowing 24 CFM though a single 120 mm fan makes more noise that blowing the same 24 CFM through an array of three 90 mm fans.
The front and back mesh covers act as a acoustic diffusers and help create laminar flow (which is less noisy than turbulent flow). Finally, the flow-through design creates a uniform convective flow over the components versus other designs with more convoluted airflows that create uneven flow or dead-air zones in the case.
I guess causing a power outage is the hackerish way to test a UPS for proper operation. Its "better" than pusghing the test button or pulling the plug on the UPS itself because it ensures that you did not forget to plug the wall wart for the router into the UPS. It also simultaneously tests all the UPSes (UPI???) in the house/office. It will also tell you if your local internet connection (be it modem, DSL, cable, someone else's Wifi net, etc.) is dependent on the local grid.
It seems to me the that real problem is inadequate transmission capacity coupled with sky-rocketing demand. Everyone wants to turn on their air conditioner and power-hungry PCs, but nobody wants to have a power line in their backyard. Throw in parochial state utility regulatory boards, half-hearted attempts at deregulation, clueless execs at utilities, and Enron and you have the makings of a bigger mess than even Microsoft can create.
Its too bad we can't just double the clock rate on the power line and transmit twice as much power. Twice the clock rate = twice as fast = twice the power??? OK, so it doesn't work like that -- but then I never understood how those tiny little electrons could go through solid metal anyhow.
120 Hz anyone?
Yes, the emate is a very nice machine and makes my point again. The emate is another example of "obsolete" hardware besting newer products. But the emate is not pocket-sized like the Psion or Zaurus
I can only hope that some future PDA will be both truely portable and truely usable. I fear the current penchant for full compatibility with MS Bloatware means that PDA makers will continue to shoehorn hot, power hungry processors into their machines. Why does a PDA need a 400 MHz processor??? So it can display some crappy, useless Flash animation???
Another nice clamshell, too bad its worse than the 3-year-old Psion 5mx. How come nobody can make a PDA with:
- A decent keyboard
- A screen you can see in full sunlight
- Battery life of at least 20 hours (my 5mx regularly gets 30+ hrs)
- A light set of applications for basic office work?
I'm not saying the Psion 5mx is perfect, but you would think that with all the miracles of modern technology that someone could have made a device at least as good. Maybe Moore's Law is being bested by Gate's Law -- new products must have every feature imaginable, even if that makes no feature actually usable.
If this cracking method is indeed patented then it must be publicly released for anyone to read and understand. But public release would seem to violate DCMA and stifling the publication would seem to violate the constitutional underpinnings of the patent system (to encourage innovation by both granting monopolies and making inventions publicly accessible for further innovation). Does this make DCMA unconstitutional???
Articles like these always confuse the role of science in society -- anything futuristic or techie is lumped under the rubric of science. Yet science really has so little to do with any of this. Scientists discover the laws, engineers develop products that make use of the laws, and businesses/governments/consumers invest in those products to adopt the fruits of the laws.
Science was done with the laws that underpin videophones, moving sidewalks, and fly cars several decades ago -- how many articles on flying cars make it into scholarly science journals these days? Engineers have been using those laws to make prototypes of the products or (more importantly) low cost approaches to manufacturing and deploying these products for quite a while.
Its the people that invest and adopt that hold up most "scientific" inventions long after science to done with the topic. Until the product is cheap enough and perceived as useful enough, all the science and engineering in the world is irrelevant. This is where marketing to cosnumers or lobbying to governments comes into play.
I don't know why people think games need to work at becoming more mainstream. Games and movies offer very different styles of entertainment to match the different moods of different people. Sometimes some people want passive entertainment -- a vicarious thrill, an interesting plot, some nice characters, or just some pleasing scenery or special effects. Sometimes some people want active entertainment -- a tough mental puzzle, intense competition, a world you can put yourself into, or just a chance to open up a big can of whoopass on some monsters.
The notion that games should be more like moves or movies should be more like games is not necessarily going to increase marketshare. Trying to merge the two is just another example of going for the lowest common denominator.
Betas and technology demos are given regularly.
Leaving aside the humorous notion of a plurality of betas, the existence of betas and technology demos are no gaurantee that the project is not getting out of hand. Multiple major slippages of the schedule are a really bad sign. And if the time between versions grows too large, the development team spends too much of the latter part of the effort fixing the obsolete parts created in the early part of the effort.
Also, betas and demos are no substitute for widespread adoption and usage of the OS because the people that look at betas & demos are markedly different from the mainstream computer-using public. Being wrapped in a cocoon of its own coders and developer devotees is likely to create code that is geek-approved and user-hated. Four years between OS versions is a long way to go without true feedback from the average user.
I'm not necessarily saying that MS does not know what they are doing or that they don't have good reasons for changing the release date. They just need to be careful that Longhorn does not turn into something like Apple's Copland.
The problem is that the actual person may also have a really tough time reproducing the same speeds, patterns, etc. in their signature.
That is the entire point of a modal analysis of the signature. It captures not only the central tendency of the signature, but also the characteristic modes of variation. The idea is that everyone's signature varies in amounts and ways that are unique to that person. Some people might vary more on the first letter, the heights of letters, the shapes of loops, slant, the spacing where the hand scoots over, etc. Analyzing a population of samples from the person gives the system a good idea about what parts of the signature vary, how they vary, and how much they vary.
The reasons for this are especially apparent when you look at the handwriting of people like myself whose fine motor control (like many guys) is not so "fine"
Like you, I too was born without an analog plotter interface. A person like myself or jtheory will simply get logged by the system as being more variable than a person like Ms. Ima Caligrapher. If a forger or mouselogger tries to replicate our signature, they will be flagged as being too perfect.
Obviously if someonce can log the mouse motions with an accurate timestamp, then they can replicate the signature. But then EVERY computer-connected biometric ID system is potentially susceptable to interception/replay of the biometric key signal.
In the case of this system, an arms race between the forger/loggers and the ID systems company would then ensue. The first countermeasure to mouse-loggers would be rejection of identical traces (as others have suggested). To this forgers would add statistical noise to the trace. The ID company would then need to create a more sophisticated statistical test that rejects traces that did not vary enough while staying within the statistical bounds of the 20 training samples that the systems asks for. An SVD on some transform of the sample signatures would help uncover both the strongest and weakest modes of variation. Signatures that did not match on the main pattern and did not vary sufficiently in expected way would be rejected. This would prevent either direct play-back or a simplistic addition of noise to the mouse trace.
The presence of both a predicable static pattern (the "average" signature) and modes of variation (because people don't actually sign their name identically to the nanometer/nanosecond) makes this biometric key better than other more invariant biometric features that can be copied.
This looks like a variation on what the folks at Cybersign do. Their technology is based on matching the dynamical pattern of motion, not just the X-Y coordinate trace. A forger would have a hard time copying the variations in speed that the actual person uses even if the forger traces the same path or tries to "get good" at the signature.
Longhorn sounds like an OS development effort that is spinning out of control. Microsoft could always copy the strategy that Apple used when Apple's Copland effort blew up in 1996 -- buy a company with a Unix-based OS and switch everyone to that.
Should Microsoft call it Visual Linux#.NET or OS XP?
With a good high-gain antenna, they should be able to access wireless LANs for quite a distance. Were I in the vicinty, I would be honored to have them posting their progress through my network.
Yes and no. Fatigue WAS a major issue in the early years of aviation, but now it is well understood. As long as you have a proper understanding of the material's properties and the stresses induced by the application, then you can design to forestall or eliminate fatigue cracking. Some materials (certain types of steel) actually have infinite fatigue resistance as long as the stresses are below a critical threshold. Stress cracks are not an issue where one can employ a combination of good design, good "life" testing, good operator training, and good inspection/maintenance procedures. I'm not saying that bad things can't happen, just that they are preventable.
Ornithopters do and will work. Materials fatigue, control issues, mechanical design, aerodynamic optimization are are solvable problems. Flapping flight exploits some important aerodynamic properties that provide much higher lift than is possible with fixed wings with steady-flow. Unsteady flow aerodynamics explains the very successful flight abilities of the Bumblebee, despite the assumption-laden proofs against this fuzzy little nectar collecter.
But whether ornithopers will ever carry humans in any quantity is doubtful because the ride will, to say the least, be sickeningly bumpy. The unsteady flows over the flapping wings mean cyclic forces on the fuselage and cyclic accelerations for the passengers. The ride will be much much worse than that of a helicopter and more like the ride in a small boat riding a very rough swell. Other flapping organism don't mind the vibration and cyclic motion of flight as they are evolved to tolerate it. In contrast the human propioception system will definitely hurl when subjected to the "graceful" up and down motion of a large-scale flapping machine.
Ornithopters will make really cool recon drones, whether over battlefields or Mars, but they will make horrible passenger vehicles
This is soo old news. This vibrations-to-power technoogy was already on the market in 2002 in self-powered structural integrity systems in tennis rackets. A similar system is used in some makes of snow skis to help dampen vibrations.
Newer news was is Science News in August 9, 2003 in "Electric Foam" (sorry, I don't have a link to the full text). Its a way to make piezoelectric polypropylene foam. Although the material needs more development (it losses its piezoelectric properties at temperatures that might occur in a car glove box), the new foam could expand the use piezoelectric materials in consumer products.
Cool. I know that the CNAPs chip actually had 80 transputers per chip, of which only 64 would be enabled.
It seems to me that a relatively dense, but semirregular interconnect architecture would provide the greatest flexibility for morphing the TRIPS grid to both handle different types of code and to route around internal damage. Admittedly, more complex physical topologies raise the cost of dynamically optimising the logical topology. Have you ever looked into notions like Golumb rulers to set the physical interconnection design?
Best wishes with the project.
LOL! So True, So True! Too many places still suffer under the monopolistic thumbs of legacy telecomm companies.
;)
Perhaps its time to build a high-gain WiFi antenna and point it toward the Dulles terminal for a little long-range wardriving.
If you delve further into the project ( http://www.cs.utexas.edu/users/cart/trips/ ) then you will see that the problem of latency is the #1 motivation for the project. TRIPs appraoch to reconfiguring a grid of ALUs should help it maximize utilization. Even so, I doubt that TRIPs is a panacea because so many software problems feature patterns of execution that are undecidable without access to a large space of memory (thus the desire for huge high-speed caches). Yet a more flexible, configurable set of ALU cores and interconnecting pipes might let a computer rebalance itself for maximum performance on a wide range of different tasks including (in their words) workloads as diverse as control-bound integer codes, highly parallel threaded codes, and regular, computationally intensive streaming codes. This ability to perform well, not perfectly, on a wide range of tasks should help the design deliver good performance on mixed and variable environments such as desktop computing and complex database-driven webserving applications. Certainly, TRIPs should be superior to the more rigidly fixed designs of current CPUs or the modestly flexible VLIW-like architecture embodied in Itanium.
Those that think that multiple cores on a single die mean low yields are assuming that each core must be a multi-million transistor monstrosity like those in current desktop CPUs. They forget that you can create a useful CPU in under 100,000 transistors (e.g., the 68000). Indeed I know of one company, back in the early 90s, that sold a parallel processing board that contained 64 simple, operational transputer cores per chip(CNAPS 1064-64). Moreover, the morphware concept in TRIPs should be able to handle some density of defects in the grid of cores, including end-of-life failures, by remapping the processor net to route around dead/dying ALUs.
When I first saw this topic I chuckled -- yes the Internet is declining in quality, but it does not seem so bad. Then I went to do a quick search for what I partially remember about an old toy from my youth. A nice specific 6-term search on Google yielded a manageable 238 hits. So then I started looking at the hits.
GRRR! 80-90% of the hits where those odious faked search hit pages that spew a bunch of popular words on a page while trying to get you to come to some e-commerce site. They claim to be "Product Comparison" sites. But its gets worse than that. They all had names with 3 patterns: a fruit theme (e.g. cherryblossom, plumwind, etc.) a street/weather theme (e.g, foggyavenue, windyexpressway, etc.); or a named couple theme (samanddiane, jenniferandvictor, etc.) all prefixed with a variety subdomains like "www" "info" etc. But its gets worse than that. I visited one of the pages and found a long list of links that simply crosslink to other sites in this little corner of e-commerce hell.
So, we have an entire corner of the internet that was probably generated in software -- a cute little combinatorial program that generates a bunch of domain names and a set of heavily cross-linked webpages that are assured of getting a high rank in Google. If someone ever shuts it down, the owner only need hit the "run" button to recreate the entire web of sites.
The real problem with the Internet is that everything is too cheap and easy. It is too cheap and easy for spammers to churn out e-mail messages, too cheap and easy for e-commerce sites to combinatorially generate a thousand domain names and cross-linked site pages. When the cost of creating and distributing information is zero, the bulk of that information is worth zero. Meanwhile the cost to the recipient climbs without bounds. So paradoxically, the low cost of the internet will mean the death of the internet.
If Symantec, M$, et al really care about consumers, then they should change when consumer's credit cards are charged for buying the product. If the box and CD are useless until product activation, then consumers should not have to pay until they have successfully run the activation procedure.
I have nothing against antipiracy/product activation per se. But I do object to schemes that force people to pay up front and then jump through a series of hoops that have a non-zero probability of failure. Until a company delivers value, it should not expect consumers to deliver payment.
Point taken. As long as current is flowing through a voltage drop, there are I^2R losses.
Perhaps the problem is that we are both right. One the one hand, a fast-switch would reduce the I^2R losses through the junction during the switch from near infinite impedences to neear-zero impedance. It is true that these losses would drop with increasing speed in the semiconductor. One the other hand, losses from charging/discharging junction and trace capacitance would be still be proportional to clock-speed. So which dominates in CPUs of today? And what really limits the clockspeed in complex digital circuits -- the on-off transition time of the gate or the R/C time constant into the fan-out of the downstream junctions?