Changes in the gross volumes of malware mail are irrelevant. As long as the mean time to infection (receipt of the latest malware) is on the order of or less than the mean time to patching, computers will have problems. Only when patching is much faster than malware spreading rates can we claim even partial victory.
The other issue is the damage done by the malware. One especially dangerous piece of malware, mailed once to all susceptible machines, will be far more serious than more innocuous malware mailed thousands of times.
Besides, I suspect that malware creators have turned their attentions to more nefarious activities such as phishing. Owning someone's bank account is more valuable than owning their PC or corrupting their harddrive.
One key breakthrough will be to give computers the ability to take an intentional stance (short definition or longer essay) with regard to users. If Google could infer why I am searching instead of just what I am searching, it would be able to do a much better job. This would move from search-as-data-retrieval to search-as-intelligent-dialog.
I'm not sure if this can happen by 2015, but it seems like a key goal that is much more important than adding "Genuine People Personalities" to computers
Lizard flag in early PPC machines
on
Apple Easter Egg
·
· Score: 4, Interesting
My favorite was a real-time rendered flag with a lizard that was shown against the backdrop of the Apple campus. It came on the Powermac 8500 and OS 7.5, IIRC. It was meant to be a fun little demo of the machine's power. The mouse location controlled the angle and strength of the wind and the flag would flutter and move appropriately. If you were aggressive enough with changing the direction of the wind, the flag would break off the pole and flutter to the ground.
The earliest Mac easter egg that I remember was one that got the dog-cow to say Moof on the Page Setup dialogs circa early system 7 and a hidden break-out game that also dates from the early system 7 era.
Absolutely! Especially when you consider that a substantive chunk of that energy budget is going to run the electronics 24/7 for sensors, data collection, attitude control, storage, and the on-the-surface GPS and radio communications.
Water is an amazing medium for travel, if you don't mind going slowly.
The specs for the batteries are: 13 MJ from 52 DD Li CSC cells (12 kg). If you look at the design pic, it says "56 D cell pack." Is this the lithium D cell you mentioned?
Yes, it looks like they are using Lithium Double-D cells. And now that I look more closely at the diagram and the specs I see that the bladder fills with mineral oil to change the buoyancy. That means that the change in the weight in the tail is very small - the difference between the weight of sea water and the weight an equivalent volume of mineral oil. That is why the batteries don't have to be very heavy or move very far to change the pitch of the vehicle.
According to the scheme, it's got movable ballast (the battery packs) which shift its balance and adjust pitch and roll. But how can it pitch down and still descend if the bladder is only on its tail?
As the bladder fills with water, it should start to sink tail-first -- the "PITCH" battery pack doesn't look like it can go fore enough of the robot's center to pitch it down, and the "ROLL" one can't be heavy enough to make it pitch, as that would prevent it from ascending head-first... I'm puzzled..
Thanks for the link! The answer to your question is a matter of densities. The bladder is only filled with water whereas the batteries are at least 2 times as dense as water (unless they are using lithium D cells), so their heavy weight counterbalances the water in the bladder.
It works just like a glider (wings and no propeller). By decreasing the buoyancy of the vehicle, it sinks and the downward drop of the vehicle is converted to forward motion by the wings (just like dropping a glider off a cliff). When the vehicle ascends, the same thing happens. The numbers in the article suggest a very modest glide slope of only 3.2:1. This means that each round trip to 3300 feet and back would provide 21120 feet (6.4 km) of forward travel. Do that 3 times a day, and you can make steady progress.
Changing buoyancy and gliding takes very little energy, much less than running a propeller, so the thing can run for a long time (about 300 days, according the the article).
Re:Amazon knows that people hate sales tax
on
Book 'Em, Dano
·
· Score: 1
I think it's because people hait bait-and-switch. Many online stores don't let you see the real price (including shipping and any taxes) until after you've taken the time to enter a lot of personal information. Only then, finally, do you know what the deal really is.
You are partially right. The data also showed that people avoided shipping fees, too. But they were only willing to pay, IIRC, $1.40 to avoid $1 of those bait-and-switch shipping costs. Perhaps its a matter of expectations. On the one hand, people expect to pay some shipping costs, but may jump to a more expensive retailer if that retailer promises "free shipping" or if the low-cost retailer has excessive, hidden, shipping costs. On the other hand, people don't expect to pay sales tax and always jump to another, often more expensive, retailer when faced with paying sales tax.
Personally I'd be much happier if they simply let you enter your zip code once to show accurate, complete prices throughout the site.
I agree 110%. Some retailers do a good job of this and I tend to use them more. Curiously, in my experience, Amazon does not do a good job on this where the order is being routed to one of Amazon's partners.
What is Amazon's fair share of sales tax?
on
Book 'Em, Dano
·
· Score: 1
well, some of the customers ARE just plain stupid.
Agreed! And a smart business gives its customers what they want, even if that is stupid.
and so bezos can pull their legs, it's not amazons police service that's supposed to be paid with the sales taxes. It's the customers police protection that the cash is going to.
You don't think local retailer get any benefit from police protection? I would imagine that crime against tax-paying retailers is a big deal, too. Armed robbery, shoplifting, embezzlement aren't crimes against customers. Amazon gets no benefit from police protection against crimes against retailers. In fact, it would be in Amazon's interests if local retailers become more frequent targets of crime as that would drive more customers to Amazon.
Sales tax pays for other services that a local retailer benefits from such as tourism promotion, local festivals, parking (if not metered), and downtown rejuvenation projects. One can even argue that sales taxes for stadiums are, at least a partially, for the benefit of local businesses that get a boost from tourism. If local governments stopped maintaining the infrastructure of the downtown and shopping areas, that would hurt local retailers and help Amazon.
You are right that sales tax does pay for services that go to the customer, but its not 100%. Some fraction of the sales tax subsidizes local retailers abilities to do business and attract customers. I can see why Amazon would not want to fund the competition, especially as Amazon (and its employees) have no vote in local elections.
Amazon knows that people hate sales tax
on
Book 'Em, Dano
·
· Score: 4, Interesting
I know why Amazon does not want to pay sales tax and its not just the small price difference of the tax or the administrative headaches. The fact is that people really really hate paying taxes to the point of irrationality. I saw the results from an e-commerce study done by MIT on people's on-line spending habits. It showed that a person would rather go with a more expensive online store in order to avoid paying sales tax. In fact, the data suggested that people would pay $5 more for the product to avoid $1 of sales tax.
I'm not sure what the solution is, but I'm sure that Amazon knows that being tax-free means more than it seems when it comes to consumer behavior.
With the current wave of outsourcing, privatization, and government use of commercial contractors, I wonder if Amazon or Google don't have a major role to play in the process of cataloging/archiving/serving digital content in the future.
Although LOC could never be replaced by a Google or Amazon, these private companies could provide services that augment or reduce the cost of LOC-like services. For example, if Amazon scans a book, why should LOC scan it too?
As far as I can tell (IANAP) so many of these scientific gnashings of teeth involve discrepancies between observations and intuitive notions for "how things should work." The human mind seems to really like simple laws and fixed constants. But what if the constants aren't and the "laws" are convoluted, contingent, or stochastic?
I'm not saying that we should not keep trying to create a self-consistent understanding of the universe, only that we be careful about foisting our human predilections for tidy explanations on to the developing theories and accumulating data.
I wonder how this will work if you give an Amazon-bought book to someone? As the registered buyer of the book, the gift giver would, presumably, have access to the electronic copy even as the give up the physical copy.
That way you can give the book and read it too.
I suppose the solution is a transferable ownership certificate (paper receipt with code or online transfer process -- yay, another claim for a patent), but I wonder how many people will actually bother to keep/give/input the certificate.
Most Plant genomes are crazy complex. Besides that, polyploidy is often the norm in plant chromosomes. With that much genetic material to work with, i guess you'd be bound to find a 'do-over' someplace.
Exactly, and there's a reason for that crazy complexity. The core challenge for a plant is that it cannot move. It has to handle all the processes of life whilst living where ever it happened to sprout. If the sunlight is intense or shaded; if the ground is wet or dry; if a caterpillar munches on the plant; if the soil is laced with silicon or deficient in phosphorus; or whatever, the plant can't do much about it but activate/deactivate genes. As a result, they have evolved a more complex genome with a greater number of IF-THEN or CASE statements built-in.
In contrast, most animals are nicely mobile, if they don't like their environment, they move to a better location. As such animals don't need as complex a genome because they spend most of their lives in their chosen micro-climate.
For projects below a certain complexity level, I've always found scripting languages to be more productive for the programmer (very fast edit-run-debug cycles) even if they are less efficient for the CPU. And with the advent of JIT compilers, the efficiency of scripting is much improved.
Given the low-cost of fast CPUs and high-cost of programmers, I'd rather waste CPU cycles than waste developer labor.
Programmable calculators, especially the gems created by HP in its calculator hey-day, do below on the list. The HP-65, introduced in 1974, was billed as the "smallest programmable computer ever" It had mass storage (magnetic cards), assembly language, a stack, registers, everything you need for basic computing.
Early programmable calculators were surprisingly powerful for their day and you could learn all the basics of computing from them. (Plus on ones like the HP-67 and HP-25 you could write a program that flashed "ShELL.OiL" "SELLS" "BOILED.OIL" when you held the calculator upside down)
Replication: Science thrives on replicable results. If researchers don't publish everything, others cannot replicate the results and the original findings become suspect.
Knowledge Sharing: If the point of publicly funded academic research is to advance human understand of the world, then open access to methods (code) is a key part of that.
Reduce/Eliminate Stealth Patents: Releasing knowledge into the public domain will help nip patents in the bud.
Preserve Fair Use: University's trends toward turning research into money is threatening the basis of fair use for researchers. How long will it take intellectual property owners to get regulations on "fair use" because academic research has turned into another big, for-profit, corporate enterprise.
Arguments against open-source science:
Replication: Science thrives on replicable results. But the key is independent verification. If one scientist simply reuses another scientist's code, there is a chance (high, some would argue) that faults in that original code would corrupt both scientists' results. Closed-source forces independent verification.
Commercialization: If the point of publicly funded academic research is to create widely-used products and services, then the system needs some scheme for protecting the value of intellectual assets. Where the cost of bringing the product to market is very high (e.g., pharma), the company/investors needs some assurance that another company can't just copy the results when the product comes out.
Maggots (or some other little parasitic vermiform beastie) would seem to be an excellent starting point for medical biobots. They have all the machinery for motion inside a living body and a neat little tool for slurping up flesh. Perhaps a bit of genetic engineering would give the critters a taste for tumor tissues or fat cells (and an abhorrence for critical tissues such as nerve cells, muscle tissue, or blood vessels).
After all the problems with spoofed emails, you would think that the people that create VOIP standards would specify something more secure. Doesn't anybody learn any lessons?
Perhaps all standards-setting bodies need a "Red Team" group of people that try to find the holes before the standard is set.
I fear that this trend will lead to the use of image compression for movies. I find the MPEG compression artifacts in most digital video (e.g., TiVo, DVDs, and digital cable) to be obnoxious -- digital quality is often an oxymoron due to aggressive compression.
Digital video may avoid analog noise and be capable of perfect copies, but if the sender uses too high a compression ratio (and you know they will to save on bandwidth and storage) then the image is permanently corrupted. And if film makers switch to digital video that does not use loss-less compression during filming, then all is lost.
I can only hope that falling prices for bandwidth and storage will let companies ease off the compression ratio sometime in the future.
Apart from some hard-wired devices (simple sound clip recorders) or downclocked low-end devices, I don't see how defective chips can be used. The article suggests that the occasional error is OK for audio and video, but how do you ensure that the faulty chip never has to handle code, memory pointers, configuration files, hashes, passwords, encrypted data, or compressed data. I suspect that modern-day audio and video datastreams are becoming more fragile as they carry more metadata, highly compressed data, DRM, software, etc.
Something tells me that the manufacturers that use semi-defective chips are going to lose all their savings on product returns, warranty costs, and technical support. Given the low cost of most consumer electronics chips and the high cost of service labor, I doubt they will want the hassles of unreliable products.
As an ever-evolving, ever-accumulating storehouse of knowledge, the articles are never done and thus never "full-length." A more meaningful statistic might be the total number of words, cross-links, and articles. A nice measure of the incompleteness would be the number of red links denoting pages that have yet to have an entry.
A copy of a 10-year-old OS does everything it did when it was first compiled and installed (and maybe a bit more with the right add-ons). It is the software-industry (and virus writers) that reset peoples expectations and make the old OS seem decrepit.
Sometimes maintaining an old OS for an old system can be the best use of time and money. I have a 10-year-old machine that does a great job scanning old slides, negatives, and photos. And another 10-year-old laptop ($20 for the laptop, $2 for a WiFi card for it) that is perfect for light editing jobs and running a much-loved application that is no longer supported on newer machines (and that has no modern counterpart). So many common computing tasks don't need GHz speed or the latest OS.
Sometimes the best tool for the job is an old tool because old software never wears out (and old hardware is so delightfully cheap).
The core objection is that ultrawideband steps on other people's spectrum used by other applications such as cell phones, satellite broadcasts, GPS, etc. Proponents claim that because the technology is ultrawideband, it deposits very little energy in any narrow slice of spectrum used by these other users. Opponents worry about what happens when a UWB transmitter is near one of there devices (yes, it can interfere with GPS) or if the world becomes saturated with UWB devices.
The problem is that each UWB device will raise the noise level in all the spectral bands that it covers. With enough UWB devices (or short enough distances to a UWB device), the utility of these other bands will drop. If you paid 5 billion dollars for something, you might scream if someone else started degrading the performance of your investment.
I think self-replicating machines might be further in the future that this article suggests. I notice, for example, that the little robot contains several crucial non-self-replicated components such as the chips, motors, rubber tires, and batteries. This leads to thoughts of a complete list of the materials needed for a true self-replicator. These materials, and the self-replicating systems to handle them, must provide capabilties that include:
Structure: The core parts of the device need a strong, stable material that can hold everything together.
Motion: The device needs materials that convert energy into mechanical motion. These materials might include electromagnetics, electrostatics, piezoelectrics, shape-memory alloys, chemo-dynamic protein muscles, thermodynamic cycle systems, etc. Each of these types of motion-creating materials has special needs/chemicals that might require special handling devices that, in turn, must be made out of the materials in the self-replicating device. Motion is often tricky because it requires specialized assemblies of materials (think of the complexity of a simple DC electric motor or the gears and linkages in a robotic arm).
Control: The device needs some form of logic that can read some analog of a blue-print, ROM, DNA, etc. and direct the fabrication process. If based on standard electronics, this would include materials that act as insulators, conductors, and semiconductors.
Power: This may be the trickiest because creating sufficient power requires purified, highly engineered materials. Self-replicating a modern alkaline battery would be quite a feat. Perhaps the semiconductor technology of the control materials could be leveraged for solar panels.
I suspect that one of the trickiest part of all this is in handling and converting bulk materials (usually a liquid, powder, or solid ingot) into a shaped and controlled component or assembly. The replicator must interface with raw materials supplies, move bulk materials to a fabrication point, and convert the bulk material into a usable component in its offspring. Space exploring self-replicators face an even greater challenge of processing raw space materials (moon rock, asteroidal metals, etc.) into refined feed-stocks for replication.
Its a tricky problem, but one that we will eventually solve.
Slashdot Mirror
Changes in the gross volumes of malware mail are irrelevant. As long as the mean time to infection (receipt of the latest malware) is on the order of or less than the mean time to patching, computers will have problems. Only when patching is much faster than malware spreading rates can we claim even partial victory.
The other issue is the damage done by the malware. One especially dangerous piece of malware, mailed once to all susceptible machines, will be far more serious than more innocuous malware mailed thousands of times.
Besides, I suspect that malware creators have turned their attentions to more nefarious activities such as phishing. Owning someone's bank account is more valuable than owning their PC or corrupting their harddrive.
One key breakthrough will be to give computers the ability to take an intentional stance (short definition or longer essay) with regard to users. If Google could infer why I am searching instead of just what I am searching, it would be able to do a much better job. This would move from search-as-data-retrieval to search-as-intelligent-dialog.
I'm not sure if this can happen by 2015, but it seems like a key goal that is much more important than adding "Genuine People Personalities" to computers
My favorite was a real-time rendered flag with a lizard that was shown against the backdrop of the Apple campus. It came on the Powermac 8500 and OS 7.5, IIRC. It was meant to be a fun little demo of the machine's power. The mouse location controlled the angle and strength of the wind and the flag would flutter and move appropriately. If you were aggressive enough with changing the direction of the wind, the flag would break off the pole and flutter to the ground.
The earliest Mac easter egg that I remember was one that got the dog-cow to say Moof on the Page Setup dialogs circa early system 7 and a hidden break-out game that also dates from the early system 7 era.
The vehicle has an amazing fuel efficiency!
Absolutely! Especially when you consider that a substantive chunk of that energy budget is going to run the electronics 24/7 for sensors, data collection, attitude control, storage, and the on-the-surface GPS and radio communications.
Water is an amazing medium for travel, if you don't mind going slowly.
The specs for the batteries are: 13 MJ from 52 DD Li CSC cells (12 kg). If you look at the design pic, it says "56 D cell pack." Is this the lithium D cell you mentioned?
Yes, it looks like they are using Lithium Double-D cells. And now that I look more closely at the diagram and the specs I see that the bladder fills with mineral oil to change the buoyancy. That means that the change in the weight in the tail is very small - the difference between the weight of sea water and the weight an equivalent volume of mineral oil. That is why the batteries don't have to be very heavy or move very far to change the pitch of the vehicle.
According to the scheme, it's got movable ballast (the battery packs) which shift its balance and adjust pitch and roll. But how can it pitch down and still descend if the bladder is only on its tail?
As the bladder fills with water, it should start to sink tail-first -- the "PITCH" battery pack doesn't look like it can go fore enough of the robot's center to pitch it down, and the "ROLL" one can't be heavy enough to make it pitch, as that would prevent it from ascending head-first... I'm puzzled..
Thanks for the link! The answer to your question is a matter of densities. The bladder is only filled with water whereas the batteries are at least 2 times as dense as water (unless they are using lithium D cells), so their heavy weight counterbalances the water in the bladder.
It works just like a glider (wings and no propeller). By decreasing the buoyancy of the vehicle, it sinks and the downward drop of the vehicle is converted to forward motion by the wings (just like dropping a glider off a cliff). When the vehicle ascends, the same thing happens. The numbers in the article suggest a very modest glide slope of only 3.2:1. This means that each round trip to 3300 feet and back would provide 21120 feet (6.4 km) of forward travel. Do that 3 times a day, and you can make steady progress.
Changing buoyancy and gliding takes very little energy, much less than running a propeller, so the thing can run for a long time (about 300 days, according the the article).
I think it's because people hait bait-and-switch. Many online stores don't let you see the real price (including shipping and any taxes) until after you've taken the time to enter a lot of personal information. Only then, finally, do you know what the deal really is.
You are partially right. The data also showed that people avoided shipping fees, too. But they were only willing to pay, IIRC, $1.40 to avoid $1 of those bait-and-switch shipping costs. Perhaps its a matter of expectations. On the one hand, people expect to pay some shipping costs, but may jump to a more expensive retailer if that retailer promises "free shipping" or if the low-cost retailer has excessive, hidden, shipping costs. On the other hand, people don't expect to pay sales tax and always jump to another, often more expensive, retailer when faced with paying sales tax.
Personally I'd be much happier if they simply let you enter your zip code once to show accurate, complete prices throughout the site.
I agree 110%. Some retailers do a good job of this and I tend to use them more. Curiously, in my experience, Amazon does not do a good job on this where the order is being routed to one of Amazon's partners.
well, some of the customers ARE just plain stupid.
Agreed! And a smart business gives its customers what they want, even if that is stupid.
and so bezos can pull their legs, it's not amazons police service that's supposed to be paid with the sales taxes. It's the customers police protection that the cash is going to.
You don't think local retailer get any benefit from police protection? I would imagine that crime against tax-paying retailers is a big deal, too. Armed robbery, shoplifting, embezzlement aren't crimes against customers. Amazon gets no benefit from police protection against crimes against retailers. In fact, it would be in Amazon's interests if local retailers become more frequent targets of crime as that would drive more customers to Amazon.
Sales tax pays for other services that a local retailer benefits from such as tourism promotion, local festivals, parking (if not metered), and downtown rejuvenation projects. One can even argue that sales taxes for stadiums are, at least a partially, for the benefit of local businesses that get a boost from tourism. If local governments stopped maintaining the infrastructure of the downtown and shopping areas, that would hurt local retailers and help Amazon.
You are right that sales tax does pay for services that go to the customer, but its not 100%. Some fraction of the sales tax subsidizes local retailers abilities to do business and attract customers. I can see why Amazon would not want to fund the competition, especially as Amazon (and its employees) have no vote in local elections.
I know why Amazon does not want to pay sales tax and its not just the small price difference of the tax or the administrative headaches. The fact is that people really really hate paying taxes to the point of irrationality. I saw the results from an e-commerce study done by MIT on people's on-line spending habits. It showed that a person would rather go with a more expensive online store in order to avoid paying sales tax. In fact, the data suggested that people would pay $5 more for the product to avoid $1 of sales tax.
I'm not sure what the solution is, but I'm sure that Amazon knows that being tax-free means more than it seems when it comes to consumer behavior.
With the current wave of outsourcing, privatization, and government use of commercial contractors, I wonder if Amazon or Google don't have a major role to play in the process of cataloging/archiving/serving digital content in the future.
Although LOC could never be replaced by a Google or Amazon, these private companies could provide services that augment or reduce the cost of LOC-like services. For example, if Amazon scans a book, why should LOC scan it too?
As far as I can tell (IANAP) so many of these scientific gnashings of teeth involve discrepancies between observations and intuitive notions for "how things should work." The human mind seems to really like simple laws and fixed constants. But what if the constants aren't and the "laws" are convoluted, contingent, or stochastic?
I'm not saying that we should not keep trying to create a self-consistent understanding of the universe, only that we be careful about foisting our human predilections for tidy explanations on to the developing theories and accumulating data.
I wonder how this will work if you give an Amazon-bought book to someone? As the registered buyer of the book, the gift giver would, presumably, have access to the electronic copy even as the give up the physical copy.
That way you can give the book and read it too.
I suppose the solution is a transferable ownership certificate (paper receipt with code or online transfer process -- yay, another claim for a patent), but I wonder how many people will actually bother to keep/give/input the certificate.
Most Plant genomes are crazy complex. Besides that, polyploidy is often the norm in plant chromosomes. With that much genetic material to work with, i guess you'd be bound to find a 'do-over' someplace.
Exactly, and there's a reason for that crazy complexity. The core challenge for a plant is that it cannot move. It has to handle all the processes of life whilst living where ever it happened to sprout. If the sunlight is intense or shaded; if the ground is wet or dry; if a caterpillar munches on the plant; if the soil is laced with silicon or deficient in phosphorus; or whatever, the plant can't do much about it but activate/deactivate genes. As a result, they have evolved a more complex genome with a greater number of IF-THEN or CASE statements built-in.
In contrast, most animals are nicely mobile, if they don't like their environment, they move to a better location. As such animals don't need as complex a genome because they spend most of their lives in their chosen micro-climate.
For projects below a certain complexity level, I've always found scripting languages to be more productive for the programmer (very fast edit-run-debug cycles) even if they are less efficient for the CPU. And with the advent of JIT compilers, the efficiency of scripting is much improved.
Given the low-cost of fast CPUs and high-cost of programmers, I'd rather waste CPU cycles than waste developer labor.
Programmable calculators, especially the gems created by HP in its calculator hey-day, do below on the list. The HP-65, introduced in 1974, was billed as the "smallest programmable computer ever" It had mass storage (magnetic cards), assembly language, a stack, registers, everything you need for basic computing.
Early programmable calculators were surprisingly powerful for their day and you could learn all the basics of computing from them. (Plus on ones like the HP-67 and HP-25 you could write a program that flashed "ShELL.OiL" "SELLS" "BOILED.OIL" when you held the calculator upside down)
Arguments against open-source science:
I'm sure there are arguments on both sides.
Maggots (or some other little parasitic vermiform beastie) would seem to be an excellent starting point for medical biobots. They have all the machinery for motion inside a living body and a neat little tool for slurping up flesh. Perhaps a bit of genetic engineering would give the critters a taste for tumor tissues or fat cells (and an abhorrence for critical tissues such as nerve cells, muscle tissue, or blood vessels).
After all the problems with spoofed emails, you would think that the people that create VOIP standards would specify something more secure. Doesn't anybody learn any lessons?
Perhaps all standards-setting bodies need a "Red Team" group of people that try to find the holes before the standard is set.
I fear that this trend will lead to the use of image compression for movies. I find the MPEG compression artifacts in most digital video (e.g., TiVo, DVDs, and digital cable) to be obnoxious -- digital quality is often an oxymoron due to aggressive compression.
Digital video may avoid analog noise and be capable of perfect copies, but if the sender uses too high a compression ratio (and you know they will to save on bandwidth and storage) then the image is permanently corrupted. And if film makers switch to digital video that does not use loss-less compression during filming, then all is lost.
I can only hope that falling prices for bandwidth and storage will let companies ease off the compression ratio sometime in the future.
Apart from some hard-wired devices (simple sound clip recorders) or downclocked low-end devices, I don't see how defective chips can be used. The article suggests that the occasional error is OK for audio and video, but how do you ensure that the faulty chip never has to handle code, memory pointers, configuration files, hashes, passwords, encrypted data, or compressed data. I suspect that modern-day audio and video datastreams are becoming more fragile as they carry more metadata, highly compressed data, DRM, software, etc.
Something tells me that the manufacturers that use semi-defective chips are going to lose all their savings on product returns, warranty costs, and technical support. Given the low cost of most consumer electronics chips and the high cost of service labor, I doubt they will want the hassles of unreliable products.
As an ever-evolving, ever-accumulating storehouse of knowledge, the articles are never done and thus never "full-length." A more meaningful statistic might be the total number of words, cross-links, and articles. A nice measure of the incompleteness would be the number of red links denoting pages that have yet to have an entry.
A copy of a 10-year-old OS does everything it did when it was first compiled and installed (and maybe a bit more with the right add-ons). It is the software-industry (and virus writers) that reset peoples expectations and make the old OS seem decrepit.
Sometimes maintaining an old OS for an old system can be the best use of time and money. I have a 10-year-old machine that does a great job scanning old slides, negatives, and photos. And another 10-year-old laptop ($20 for the laptop, $2 for a WiFi card for it) that is perfect for light editing jobs and running a much-loved application that is no longer supported on newer machines (and that has no modern counterpart). So many common computing tasks don't need GHz speed or the latest OS.
Sometimes the best tool for the job is an old tool because old software never wears out (and old hardware is so delightfully cheap).
The core objection is that ultrawideband steps on other people's spectrum used by other applications such as cell phones, satellite broadcasts, GPS, etc. Proponents claim that because the technology is ultrawideband, it deposits very little energy in any narrow slice of spectrum used by these other users. Opponents worry about what happens when a UWB transmitter is near one of there devices (yes, it can interfere with GPS) or if the world becomes saturated with UWB devices.
The problem is that each UWB device will raise the noise level in all the spectral bands that it covers. With enough UWB devices (or short enough distances to a UWB device), the utility of these other bands will drop. If you paid 5 billion dollars for something, you might scream if someone else started degrading the performance of your investment.
- Structure: The core parts of the device need a strong, stable material that can hold everything together.
- Motion: The device needs materials that convert energy into mechanical motion. These materials might include electromagnetics, electrostatics, piezoelectrics, shape-memory alloys, chemo-dynamic protein muscles, thermodynamic cycle systems, etc. Each of these types of motion-creating materials has special needs/chemicals that might require special handling devices that, in turn, must be made out of the materials in the self-replicating device. Motion is often tricky because it requires specialized assemblies of materials (think of the complexity of a simple DC electric motor or the gears and linkages in a robotic arm).
- Control: The device needs some form of logic that can read some analog of a blue-print, ROM, DNA, etc. and direct the fabrication process. If based on standard electronics, this would include materials that act as insulators, conductors, and semiconductors.
- Power: This may be the trickiest because creating sufficient power requires purified, highly engineered materials. Self-replicating a modern alkaline battery would be quite a feat. Perhaps the semiconductor technology of the control materials could be leveraged for solar panels.
I suspect that one of the trickiest part of all this is in handling and converting bulk materials (usually a liquid, powder, or solid ingot) into a shaped and controlled component or assembly. The replicator must interface with raw materials supplies, move bulk materials to a fabrication point, and convert the bulk material into a usable component in its offspring. Space exploring self-replicators face an even greater challenge of processing raw space materials (moon rock, asteroidal metals, etc.) into refined feed-stocks for replication.Its a tricky problem, but one that we will eventually solve.