Although DARPA might rejigger people's appetites and metabolism to avoid the need for food, they can't avoid the the physical constraints of conservation of energy. Even if a soldier is just waiting in a fox hole, they need 2000 calories per day of energy. If the fighting is intense (the time when no eating is possible) then they might need more tha 5000 calories per day of energy.
This means a soldiers needs between 10,000 and 25,000 of energy reserves for a 5-day stint. This means that these soldiers wil need 3 to 7 pounds of excess body fat (more if the soldiers is expected to last several rounds of 5-day food deprivation). Without excess body fat, the body will start mateabolizing muscle tissue and that won't be very good for military readiness.
Maybe all those overweight American kids might make good soldiers after all.
The bill makes no mention of who will have to pay for the device, but it will most likely be auto dealers and citizens who have to sell their cars.
Car sellers will not "pay" for this device, car buyers will. If it costs $200 to add the device, you can be sure that car prices with rise $200 in New Mexico. This is the same logic that has government paying for things, when it is really the taxpayer that pays. Businesses, like governments, pass their spending on to customers and taxpayers respectively.
The only exception is if a business faces competition that does not have to install this gizmo. So we can expect to see some booming car sales on the borders near New Mexico.
People really need to stop looking at businesses and government as big money machines. These organizations may have lots of money, but they got it from someplace else.
Morse code is an early variable-length data compression stanard (similar to Huffman codes or Shannon-Fano codes). By representing common letters with shorter codes ("E = "," and "T" = "-") and rare letters with longer codes ("Z" = "--.." an "Q" = "--.-"), Morse code manages to encode the 26 letters of the alphabet in 4 bits maximum and much less than 4 bits per letter on average.
Although Morse did use letter frequencies in constructing his code, it is not a truely optimized code, from what I can tell. Numbers are encoded with a cumbersome 5 bits per digit. Also, the transmission time of messages might be further reduced with minor rearrangements of the code to use more dots (short transmission time) in more frequent letters and more dashes (long transmission time) in the less frequent letters.
Not to defend spam, but this issue of economic rationality applies to the recipients of spam too. For too many people, the cost of searching for a product exceeds the cost of clicking through a spam email. HTML email and the internet have made it too easy for the recipients of marketing material to satisfy their curiosity (and buy) from spam. In contrast, taking the initative, opening up a web page to Google, searching for a product, and reserach company reputations is too much bother for too many people.
I suspect that many people see spam-promoted products as no more disreputable than companies found by a search, so why not buy from the most convenitent channel? There may even be a perverse psychological drive that favors spam. If you get screwed by a company that you actively searched for and selected, then you feel like a complete idiot. If you get screwed by a spam compnay, then you can (at least psychologically) partially blame the company that sought you out.
As long as it is easier to click through a spam to reward a spammer (and people are lazy), spammers will be rewarded.
Large scale networks have limitations because real relationships are complex. The notion of A-is-a-friend-of-B or A-trusts-B is too simplistic for large scale networks. These connectivity relationships are not transitive in real-life (A-trusts-B & B-trusts-C does not imply A-trusts-C)
Rather, the network needs some form of role-based assertion or qualification of the relationship. I know friends that I like to go hiking with, but that I disagree with politically. I know people that I do trust to recommend software, but don't trust to recommend a restaurant. And if I trust person B to recommend software, I would probably only trust that person B to recommend another person C in a limited set of domains (like software or technical issues). Thus the real relationship is more like person-A-trusts-person-B-for-role-C.
Such a scheme of role-defined relationships could be self-organizing or predefined. The self-organizing approach would look for disjoint clusters of members in a network or use semantic analysis of the messages passed between people to infer a set of role-clusters. Predefined relationship might be OK, but could become unwieldly if the network creators force people to answer a long multiple-choice test about every relationship.
As a non-gamer I am truly curious about the impact of these latest graphics cards for regular everyday use (spreadsheets, word processing, photoshop, etc.). Do these cards do anything to improve 2-D performance (scrolling, image manipulations, large screen displays?). I would assume that the inproved memory bandwidth helps a few percent, but that all the vertex shaders & pipelines mean little to 2-D office and graphics applications.
One solution to the monoculture problem is multi-OS architectures in which a single process is executed on multiple independent codebases within each box.
On high-reliability systems (Space Shuttle & X-29 flight controls), multiple redundant subprocessors attempt to compute the same answer. If the subprocessors get different answers, the majority-rules and the system logs the exception. If each processor ran independent code, then exploits of any one codebase would be detected and disinfected. A multi-system with one exploited/infected codebase would continue running while ignoring the output of the infected subprocessor.
The system would still have some vulnerabilties. Simultaneous attack on a majority of the codebases might succeed in redefinig the majority to suit the malware. Also, codebase independence is very hard. More than likely several codebases might share the same fault (e.g. a buffer overrun bug). Attacks on the overseer/majority-rules system might also succeed. Finally, if the standard has an exploit (e.g., decrypting WiFi WEP), then all codebases implementing the standard are vulnerable.
The biggest downside is bloat and cost. But at least it would give people a reason to buy the latest greatest chips from Intel, AMD, IBM, etc.
It's not just monoculture that makes viruses spread so quickly. The fact that any computer can send something to any computer is bad. The fact that any computer can send something to so many computers is terrible.
Even if Linus drives Microsoft products into the minority, infections would still quickly reach Microsoft machines (or machines of any leading platform). Furthermore, under non-monoculture conditions, the dilution of virus writers on any one platform would probably be matched by the dilution of anti-virus resources on that platform. Even under non-monoculture conditions, we'll still have fast-spreading infections.
Just how strong can these gravitational lenses be? Caustics would sem to create a potential for extremely high light intensification. I wonder if any exterrestrial civilizations have been accidentally killed by a gravitational lensing event. Fortunately, I suspect that this is extremely unlikely because of the distances involved (a thousand-fold amplification of a galaxy a billion light year s away is no big deal).
Still, I do wonder if an unfortunate alignment of a supernova, blackhole, and an unsuspecting planet (on a scale of a few thousnad light years)could have tragic results.
I would suspect that Open Source is limited to particular categories of work. Labor intensive, but not capital intensive, activities are ideal for open source. With capital intensive endevours, the people that own the money want to own the output. Fortunatly, the captial required for many activities is dropping. With the low cost and ubiquity of technlogy, many formly expensive activities can be done by amateurs on an open source basis (software, indie films, encyclopedias/wikis, helpdesk/help forums, etc.).
For bigger open source projects, the problem is monetization -- converting the fruits of open source into money that goes to pay the burgeoning and unavoidable expenses of a large project. The free-software, expensive service model (RedHat) or free software, expensive hardware & service model (IBM) seems popular.
But there are limits. I doubt we will ever see open source retail stores, hardware factories, or apartment buildings (except on an unusual donation basis). Probably the only capital-intensive forms of "open source" is university science -- the scientists provide the labor, release there findngs to the public, and the government provides the money for the equipment (even here, university IP people try to own the fruits of the academic labors).
And the impact on the environment?
on
Hack Your Car
·
· Score: 4, Insightful
Most cars are tuned for a compromise of fuel efficiency, low pollution, and reliability. So these mods will adversely affect these more mundane automotive goals.
On the one hand, these high performance mods probably turn the car into serious emitter of nasty gases.
On the other hand, the added stress probably shortens the lifespan of the engine and gets the car off the road that much sooner.
However, by the same token the very systems which make us "intuitive" and pattern-oriented are subject to the laws of science which are grounded in logic, no?
Absolutely true! But the issue is that I don't have know the laws of physics to catch a baseball (not that I, as a geek, can catch a baseball). So can I write "intuitive" software that catches baseballs without knowing all those complicated non-intuitive laws of physics, kinematics, control theory, etc? This leads to your second point.
I agree with you, but only temporarily - I think it's only a matter of time (more specifically, time to figure out exactly how we do this kind of thing)
Actually, I agree with you that the gulf betwen binary logic and intuitive analog reasoning is only temporary. Neurons are adaptive nonlinear statistical correlators. As such they are readily replicatable in software. The only ugly issue is efficiency -- it takes too many transistors and too many clock cycle to emulate even a small number of neurons. Thus, although I think we can create computers that emulate meatware and "think" like we do (with enough power), I'm not sure that it represents a very good use of computer power.
Now going back to your first point, even if we have a NeuroPentium processor, we still need to do some serious non-intuitive engineering to create the base hardware that can intuitively interact with our world. And this issue does not even address the fact that so many business world applications (like accounting packages and tax software) represent fundamentally non-intuive problem domains.
Perhaps the deeper problem is that we humans have created a deeply nonintituive "real" world for ourselves. Our complex world of laws, budgets, money, and mass-production has gone too far beyond our old tribal hunter-gatherer origins. Even if we could create intuitive software, we could not create the applications that the current real world calls for.
Having watched many people struggle with physics, chemistry, and biology courses, I'm not sure that the real world is all that inituitive. Even in the non-scientific informal world, many people have incorrect intuitive models for how things work. For example, many people think that increasing the setting on the thermostat will make the room warm up faster (vs. warming at a constant rate, but reaching a higher temperature eventually). And my wife still thinks that turning off the TV will disrupt the functioning of the VCR.
Another problem is that the real world is both analog and approximate, while the digital world calls for hard-edged distinctions. In the real world, close-enough is good enough for many physical activities (driving inside the white lines, parking near a destination, cooking food long enough). In contrast, if I am moving or removing files from a file system, I need an algorithm that clearly distinguishes between those in the selection set and those outside it.
I like the idea of intuitive programming, but suspect that computers are grounded in logic and that logic is not an intuitive concept.
This type of discovery highlights the potential value of a distributed effort to continuously resurvey the sky. If a group of amateurs agreed to take pictures of selected (preallocated) spots in the sky, and send in the pictures, then we could find the events like comets, asteroids, novae, variable stars, etc. on a more timely basis. An amateur network could even send out re-imaging instructions or multiple-telescope coverage instructions to help disambiguate faint signals or triangulate on in-system objects.
The effort could even use a SETI-like distributed process to have idle computers do the image-to-image registration and differencing needed to detect changes in the images of the sky. Each computer would have reference images of some part of the sky and send back a "hit list" of potentially interesting image elements. The hit list would drive future observations (or reobservations) and ultimately be broadcast to the professional community for more intensive study of new astonomical phenomena.
Denser packing of powders in sintered materials should improve their strength. But I bet the ultimate properties of materials made with ellipsoidal powders will be more complex than predicted from the packing density.
Granular materials tend to be weakest at the grain interfaces. Such materials tend to fail by breaking the grain-to-grain contacts, rather than shearing through the grains themselves. Thus, the geometry of the contact points will play a big role in the material's strength. I'd bet that ellipsoidal particle aggregates have more contact points because the elongated grains reach across the aggregate to touch more other grains. This should increase strength (materialsmade from ellipsoidal powers will be eve stronger than expected).
But the story might be even more complicated if large collections of grains have correlated orientations. If all of the grains in a region are oriented in the same way, that region will have highly anisotropic properties (extra weak in some directions and extra strong in other). Parts made with ellisoidal powders may have nonuniform strength in two senses. First, the parts may be weak in some directions, stronger in others(very good or very bad depending on how the design handles strength vis a vis the particle orientations). Second, if the packing orientations vary from part to part (or within macroscopic domains in parts), then the parts may vary in strength across different parts or across batches of parts (bad because inconsistent quality is bad).
I'm sure that Microsoft now wishes that it source code files had been locked into self-expiring, heavily encrypted, copy-resistant file formats. Events like this can only increase demands for "Trusted Computing" initiatives that prevent accidental or intentional leakage of security-sensitive intellectual property.
Given that so many companies outsource or collaborate with a far-flung global network of suppliers -- I'm sure MSFT need only whisper about the threat of leaked trade secrets to get corporate IT to adopt DRM/Trusted computing for everyday use.
What the original article misses the incredible value of transparency. That anyone can examine the code for potential exploits makes open source far more secure.
Until the public can obtain a copy of the source of Windows, voting system software, etc. under FOIA (Freedom of Information Act), I suggest that governments (and others) consider the hidden insecurity of proprietary software. For closed source, it is too easy and too tempting for companies to attempt to hide exploits, bugs, and backdoors.
Its an interesting breakthrough, but only from the standpoint of manufacturing high speed optical interconnect systems using standard silicon as the substrate material. It would seem that the technology still relies on standard electronic computation, but has a convenient way to convert eletronic signals into photonic ones on a standard silicon chip (versus the more exotic materials currently used for optical modulators).
Rather than create all-optical processors, this technology will be useful for building gigabit fiber interfaces directly into everyday silicon chips. I'd think that the next step for this stuff will be cheap fiber connections between peripherals and interal subsystems (Optical ATA anyone?) Then they will look to create optical traces that connect Intel processors, cache, RAM, I/O chips (if they can figure out how to mass-produce a optical fiber traces on a PCB).
This breakthrough more of an interconnection technology than a computation technology.
I once disassembled a early model of solar-powered credit card-sized calculator (one with no battery at all). While holding the circuit board near a light, I noticed a little glow ont he backside of the board. The designer had used an LED as a cheap voltage regulator. The LED lit up to dump excess energy coming from the solar cells.
I've had a couple of occassions where Soft Windows decided it needed to launch in response to some web feature or a PC file. I've never had an infection via this route, but it seems that it is possible that double-clicking on a malware.exe file on a Macintosh could lead the Mac to attempt to invoke a Windows emulator and thus infect the emulator. Perhaps this is the Mac's way of corrupting and killing the Window's emulator;)
A peculiarity in the genetics (haplodiploidy) of insects in the order Hymenoptera is the likely underlying cause of the evolution of sociality in ants, bees, and wasps. While females (all worker bees, ants, wasps, etc. are female) have two sets of chromosomes, males only have one. This affects the relatedness of individuals. In particular, haplodiploidy makes an ant, for example, more related to its sisters than to its own daughters and sons. For ants, bees, and wasps, the most selfish way to pass on your genes is to raise more sisters. As a result, social behavior appears to independently evolved as many as 11 times in Hymenopterans -- appearing several times in the ancestors of what we now know as ants, bees, and wasps.
Sometime being social is the most selfish strategy possible.
I can only hope that they update/bring back the Psion 5 series form factor. I still use, and love, my Psion 5mx every single day. IMO, the Psion design represents a near-optimium compromise for a handheld machine: usable keyboard, large display, high portability, and reasonable connectivity/expansion.
But, above all, the old Psions have outstanding battery life. If anything, the 5mx got more battery life than the original 5, despite a 2X boost in both RAM and clock speed. I routinely get more than 30 hours of actual usuable on-time. This means I can take the thing on any business trip without worrying about batteries. And the fact that it uses standard AAs means I can replace the batteries anywhere anytime (no looking for an outlet, carrying a wallwart, getting international adapter plugs, or worrying about declining recharge life as the PDA ages). So even if I had to worry about batteries, I don't have to worry about batteries.
I hate hate hate the fact that all the "newer" and "more advanced" PDAs have a no usuable keyabord and horrible battery life. Technology is supposed to improve!
It would see that aggressive TOS with an embedded email address would be an interesting way to snare spammers. With the address only available on the TOS page (and surrounded by nasty terms), any spams to that address could only occur if the spammer "read" the TOS. I don't think it would be entrapment if the terms were reasonable (e.g., a $20 reading and handling fee for use of that address).
Not true. To design something very complicated like an aircraft or Mars rover there are *many* models and experimentation done, because almost all textbook equations are only approximations of reality.
Excellent point. My heat transfer prof warned us that the equations in the textbook would get answers that had as much as 30% error (if you were lucky). And, IIRC, some theories in material science only yield answers that are within an order of magnitude (factor of 10) of the true value.
But what I was alluding to was robustness -- designs that aren't affected by approximation errors (or the inevitable measurement errors when you build and test a prototype). Some of this is a matter of factors of safety (overdesign) but the truely great engineers create designs that are insensitive to encountered variations. At some level the ability of the Rover team to correct the recent faults represents this type of robustness. Yes, they are tweaking and hacking, but it was only because of a robust, remotely fixable design that let them do this.
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Although DARPA might rejigger people's appetites and metabolism to avoid the need for food, they can't avoid the the physical constraints of conservation of energy. Even if a soldier is just waiting in a fox hole, they need 2000 calories per day of energy. If the fighting is intense (the time when no eating is possible) then they might need more tha 5000 calories per day of energy.
This means a soldiers needs between 10,000 and 25,000 of energy reserves for a 5-day stint. This means that these soldiers wil need 3 to 7 pounds of excess body fat (more if the soldiers is expected to last several rounds of 5-day food deprivation). Without excess body fat, the body will start mateabolizing muscle tissue and that won't be very good for military readiness.
Maybe all those overweight American kids might make good soldiers after all.
The bill makes no mention of who will have to pay for the device, but it will most likely be auto dealers and citizens who have to sell their cars.
Car sellers will not "pay" for this device, car buyers will. If it costs $200 to add the device, you can be sure that car prices with rise $200 in New Mexico. This is the same logic that has government paying for things, when it is really the taxpayer that pays. Businesses, like governments, pass their spending on to customers and taxpayers respectively.
The only exception is if a business faces competition that does not have to install this gizmo. So we can expect to see some booming car sales on the borders near New Mexico.
People really need to stop looking at businesses and government as big money machines. These organizations may have lots of money, but they got it from someplace else.
Morse code is an early variable-length data compression stanard (similar to Huffman codes or Shannon-Fano codes). By representing common letters with shorter codes ("E = "," and "T" = "-") and rare letters with longer codes ("Z" = "--.." an "Q" = "--.-"), Morse code manages to encode the 26 letters of the alphabet in 4 bits maximum and much less than 4 bits per letter on average.
Although Morse did use letter frequencies in constructing his code, it is not a truely optimized code, from what I can tell. Numbers are encoded with a cumbersome 5 bits per digit. Also, the transmission time of messages might be further reduced with minor rearrangements of the code to use more dots (short transmission time) in more frequent letters and more dashes (long transmission time) in the less frequent letters.
Not to defend spam, but this issue of economic rationality applies to the recipients of spam too. For too many people, the cost of searching for a product exceeds the cost of clicking through a spam email. HTML email and the internet have made it too easy for the recipients of marketing material to satisfy their curiosity (and buy) from spam. In contrast, taking the initative, opening up a web page to Google, searching for a product, and reserach company reputations is too much bother for too many people.
I suspect that many people see spam-promoted products as no more disreputable than companies found by a search, so why not buy from the most convenitent channel? There may even be a perverse psychological drive that favors spam. If you get screwed by a company that you actively searched for and selected, then you feel like a complete idiot. If you get screwed by a spam compnay, then you can (at least psychologically) partially blame the company that sought you out.
As long as it is easier to click through a spam to reward a spammer (and people are lazy), spammers will be rewarded.
Large scale networks have limitations because real relationships are complex. The notion of A-is-a-friend-of-B or A-trusts-B is too simplistic for large scale networks. These connectivity relationships are not transitive in real-life (A-trusts-B & B-trusts-C does not imply A-trusts-C)
Rather, the network needs some form of role-based assertion or qualification of the relationship. I know friends that I like to go hiking with, but that I disagree with politically. I know people that I do trust to recommend software, but don't trust to recommend a restaurant. And if I trust person B to recommend software, I would probably only trust that person B to recommend another person C in a limited set of domains (like software or technical issues). Thus the real relationship is more like person-A-trusts-person-B-for-role-C.
Such a scheme of role-defined relationships could be self-organizing or predefined. The self-organizing approach would look for disjoint clusters of members in a network or use semantic analysis of the messages passed between people to infer a set of role-clusters. Predefined relationship might be OK, but could become unwieldly if the network creators force people to answer a long multiple-choice test about every relationship.
As a non-gamer I am truly curious about the impact of these latest graphics cards for regular everyday use (spreadsheets, word processing, photoshop, etc.). Do these cards do anything to improve 2-D performance (scrolling, image manipulations, large screen displays?). I would assume that the inproved memory bandwidth helps a few percent, but that all the vertex shaders & pipelines mean little to 2-D office and graphics applications.
I'm just curious.
One solution to the monoculture problem is multi-OS architectures in which a single process is executed on multiple independent codebases within each box.
On high-reliability systems (Space Shuttle & X-29 flight controls), multiple redundant subprocessors attempt to compute the same answer. If the subprocessors get different answers, the majority-rules and the system logs the exception. If each processor ran independent code, then exploits of any one codebase would be detected and disinfected. A multi-system with one exploited/infected codebase would continue running while ignoring the output of the infected subprocessor.
The system would still have some vulnerabilties. Simultaneous attack on a majority of the codebases might succeed in redefinig the majority to suit the malware. Also, codebase independence is very hard. More than likely several codebases might share the same fault (e.g. a buffer overrun bug). Attacks on the overseer/majority-rules system might also succeed. Finally, if the standard has an exploit (e.g., decrypting WiFi WEP), then all codebases implementing the standard are vulnerable.
The biggest downside is bloat and cost. But at least it would give people a reason to buy the latest greatest chips from Intel, AMD, IBM, etc.
It's not just monoculture that makes viruses spread so quickly. The fact that any computer can send something to any computer is bad. The fact that any computer can send something to so many computers is terrible.
Even if Linus drives Microsoft products into the minority, infections would still quickly reach Microsoft machines (or machines of any leading platform). Furthermore, under non-monoculture conditions, the dilution of virus writers on any one platform would probably be matched by the dilution of anti-virus resources on that platform. Even under non-monoculture conditions, we'll still have fast-spreading infections.
Connectivity is the real driver of infection.
Just how strong can these gravitational lenses be? Caustics would sem to create a potential for extremely high light intensification. I wonder if any exterrestrial civilizations have been accidentally killed by a gravitational lensing event. Fortunately, I suspect that this is extremely unlikely because of the distances involved (a thousand-fold amplification of a galaxy a billion light year s away is no big deal).
Still, I do wonder if an unfortunate alignment of a supernova, blackhole, and an unsuspecting planet (on a scale of a few thousnad light years)could have tragic results.
I would suspect that Open Source is limited to particular categories of work. Labor intensive, but not capital intensive, activities are ideal for open source. With capital intensive endevours, the people that own the money want to own the output. Fortunatly, the captial required for many activities is dropping. With the low cost and ubiquity of technlogy, many formly expensive activities can be done by amateurs on an open source basis (software, indie films, encyclopedias/wikis, helpdesk/help forums, etc.).
For bigger open source projects, the problem is monetization -- converting the fruits of open source into money that goes to pay the burgeoning and unavoidable expenses of a large project. The free-software, expensive service model (RedHat) or free software, expensive hardware & service model (IBM) seems popular.
But there are limits. I doubt we will ever see open source retail stores, hardware factories, or apartment buildings (except on an unusual donation basis). Probably the only capital-intensive forms of "open source" is university science -- the scientists provide the labor, release there findngs to the public, and the government provides the money for the equipment (even here, university IP people try to own the fruits of the academic labors).
Most cars are tuned for a compromise of fuel efficiency, low pollution, and reliability. So these mods will adversely affect these more mundane automotive goals.
On the one hand, these high performance mods probably turn the car into serious emitter of nasty gases.
On the other hand, the added stress probably shortens the lifespan of the engine and gets the car off the road that much sooner.
However, by the same token the very systems which make us "intuitive" and pattern-oriented are subject to the laws of science which are grounded in logic, no?
Absolutely true! But the issue is that I don't have know the laws of physics to catch a baseball (not that I, as a geek, can catch a baseball). So can I write "intuitive" software that catches baseballs without knowing all those complicated non-intuitive laws of physics, kinematics, control theory, etc? This leads to your second point.
I agree with you, but only temporarily - I think it's only a matter of time (more specifically, time to figure out exactly how we do this kind of thing)
Actually, I agree with you that the gulf betwen binary logic and intuitive analog reasoning is only temporary. Neurons are adaptive nonlinear statistical correlators. As such they are readily replicatable in software. The only ugly issue is efficiency -- it takes too many transistors and too many clock cycle to emulate even a small number of neurons. Thus, although I think we can create computers that emulate meatware and "think" like we do (with enough power), I'm not sure that it represents a very good use of computer power.
Now going back to your first point, even if we have a NeuroPentium processor, we still need to do some serious non-intuitive engineering to create the base hardware that can intuitively interact with our world. And this issue does not even address the fact that so many business world applications (like accounting packages and tax software) represent fundamentally non-intuive problem domains.
Perhaps the deeper problem is that we humans have created a deeply nonintituive "real" world for ourselves. Our complex world of laws, budgets, money, and mass-production has gone too far beyond our old tribal hunter-gatherer origins. Even if we could create intuitive software, we could not create the applications that the current real world calls for.
Having watched many people struggle with physics, chemistry, and biology courses, I'm not sure that the real world is all that inituitive. Even in the non-scientific informal world, many people have incorrect intuitive models for how things work. For example, many people think that increasing the setting on the thermostat will make the room warm up faster (vs. warming at a constant rate, but reaching a higher temperature eventually). And my wife still thinks that turning off the TV will disrupt the functioning of the VCR.
Another problem is that the real world is both analog and approximate, while the digital world calls for hard-edged distinctions. In the real world, close-enough is good enough for many physical activities (driving inside the white lines, parking near a destination, cooking food long enough). In contrast, if I am moving or removing files from a file system, I need an algorithm that clearly distinguishes between those in the selection set and those outside it.
I like the idea of intuitive programming, but suspect that computers are grounded in logic and that logic is not an intuitive concept.
This type of discovery highlights the potential value of a distributed effort to continuously resurvey the sky. If a group of amateurs agreed to take pictures of selected (preallocated) spots in the sky, and send in the pictures, then we could find the events like comets, asteroids, novae, variable stars, etc. on a more timely basis. An amateur network could even send out re-imaging instructions or multiple-telescope coverage instructions to help disambiguate faint signals or triangulate on in-system objects.
The effort could even use a SETI-like distributed process to have idle computers do the image-to-image registration and differencing needed to detect changes in the images of the sky. Each computer would have reference images of some part of the sky and send back a "hit list" of potentially interesting image elements. The hit list would drive future observations (or reobservations) and ultimately be broadcast to the professional community for more intensive study of new astonomical phenomena.
Denser packing of powders in sintered materials should improve their strength. But I bet the ultimate properties of materials made with ellipsoidal powders will be more complex than predicted from the packing density.
Granular materials tend to be weakest at the grain interfaces. Such materials tend to fail by breaking the grain-to-grain contacts, rather than shearing through the grains themselves. Thus, the geometry of the contact points will play a big role in the material's strength. I'd bet that ellipsoidal particle aggregates have more contact points because the elongated grains reach across the aggregate to touch more other grains. This should increase strength (materialsmade from ellipsoidal powers will be eve stronger than expected).
But the story might be even more complicated if large collections of grains have correlated orientations. If all of the grains in a region are oriented in the same way, that region will have highly anisotropic properties (extra weak in some directions and extra strong in other). Parts made with ellisoidal powders may have nonuniform strength in two senses. First, the parts may be weak in some directions, stronger in others(very good or very bad depending on how the design handles strength vis a vis the particle orientations). Second, if the packing orientations vary from part to part (or within macroscopic domains in parts), then the parts may vary in strength across different parts or across batches of parts (bad because inconsistent quality is bad).
Interesting story, but more research is needed.
I'm sure that Microsoft now wishes that it source code files had been locked into self-expiring, heavily encrypted, copy-resistant file formats. Events like this can only increase demands for "Trusted Computing" initiatives that prevent accidental or intentional leakage of security-sensitive intellectual property.
Given that so many companies outsource or collaborate with a far-flung global network of suppliers -- I'm sure MSFT need only whisper about the threat of leaked trade secrets to get corporate IT to adopt DRM/Trusted computing for everyday use.
What the original article misses the incredible value of transparency. That anyone can examine the code for potential exploits makes open source far more secure.
Until the public can obtain a copy of the source of Windows, voting system software, etc. under FOIA (Freedom of Information Act), I suggest that governments (and others) consider the hidden insecurity of proprietary software. For closed source, it is too easy and too tempting for companies to attempt to hide exploits, bugs, and backdoors.
Its an interesting breakthrough, but only from the standpoint of manufacturing high speed optical interconnect systems using standard silicon as the substrate material. It would seem that the technology still relies on standard electronic computation, but has a convenient way to convert eletronic signals into photonic ones on a standard silicon chip (versus the more exotic materials currently used for optical modulators).
Rather than create all-optical processors, this technology will be useful for building gigabit fiber interfaces directly into everyday silicon chips. I'd think that the next step for this stuff will be cheap fiber connections between peripherals and interal subsystems (Optical ATA anyone?) Then they will look to create optical traces that connect Intel processors, cache, RAM, I/O chips (if they can figure out how to mass-produce a optical fiber traces on a PCB).
This breakthrough more of an interconnection technology than a computation technology.
The activiation temperature of battery testers is a pleasantly toasty 100-120 F.
I once disassembled a early model of solar-powered credit card-sized calculator (one with no battery at all). While holding the circuit board near a light, I noticed a little glow ont he backside of the board. The designer had used an LED as a cheap voltage regulator. The LED lit up to dump excess energy coming from the solar cells.
I've had a couple of occassions where Soft Windows decided it needed to launch in response to some web feature or a PC file. I've never had an infection via this route, but it seems that it is possible that double-clicking on a malware .exe file on a Macintosh could lead the Mac to attempt to invoke a Windows emulator and thus infect the emulator. Perhaps this is the Mac's way of corrupting and killing the Window's emulator ;)
A peculiarity in the genetics (haplodiploidy) of insects in the order Hymenoptera is the likely underlying cause of the evolution of sociality in ants, bees, and wasps. While females (all worker bees, ants, wasps, etc. are female) have two sets of chromosomes, males only have one. This affects the relatedness of individuals. In particular, haplodiploidy makes an ant, for example, more related to its sisters than to its own daughters and sons. For ants, bees, and wasps, the most selfish way to pass on your genes is to raise more sisters. As a result, social behavior appears to independently evolved as many as 11 times in Hymenopterans -- appearing several times in the ancestors of what we now know as ants, bees, and wasps.
Sometime being social is the most selfish strategy possible.
I can only hope that they update/bring back the Psion 5 series form factor. I still use, and love, my Psion 5mx every single day. IMO, the Psion design represents a near-optimium compromise for a handheld machine: usable keyboard, large display, high portability, and reasonable connectivity/expansion.
But, above all, the old Psions have outstanding battery life. If anything, the 5mx got more battery life than the original 5, despite a 2X boost in both RAM and clock speed. I routinely get more than 30 hours of actual usuable on-time. This means I can take the thing on any business trip without worrying about batteries. And the fact that it uses standard AAs means I can replace the batteries anywhere anytime (no looking for an outlet, carrying a wallwart, getting international adapter plugs, or worrying about declining recharge life as the PDA ages). So even if I had to worry about batteries, I don't have to worry about batteries.
I hate hate hate the fact that all the "newer" and "more advanced" PDAs have a no usuable keyabord and horrible battery life. Technology is supposed to improve!
It would see that aggressive TOS with an embedded email address would be an interesting way to snare spammers. With the address only available on the TOS page (and surrounded by nasty terms), any spams to that address could only occur if the spammer "read" the TOS. I don't think it would be entrapment if the terms were reasonable (e.g., a $20 reading and handling fee for use of that address).
Not true. To design something very complicated like an aircraft or Mars rover there are *many* models and experimentation done, because almost all textbook equations are only approximations of reality.
Excellent point. My heat transfer prof warned us that the equations in the textbook would get answers that had as much as 30% error (if you were lucky). And, IIRC, some theories in material science only yield answers that are within an order of magnitude (factor of 10) of the true value.
But what I was alluding to was robustness -- designs that aren't affected by approximation errors (or the inevitable measurement errors when you build and test a prototype). Some of this is a matter of factors of safety (overdesign) but the truely great engineers create designs that are insensitive to encountered variations. At some level the ability of the Rover team to correct the recent faults represents this type of robustness. Yes, they are tweaking and hacking, but it was only because of a robust, remotely fixable design that let them do this.