UWB is great, but it is just another form of modulation. The same principles apply to the older modulation techniques apply in the same way to UWB (such as a channel's carrying capacity at a certain bandwidth, dynamic range, error rate). It ain't magic, and doesn't have any mysterious abilities (some have been postulated, none have been proved). The only real advantage I see in it is that it can be a form of modulation that is time (rather than frequency) based, so it maps well with our most common computing paradigm (a common clock, IOW synchronous). Because of this, the hardware can be made simpler-- the elimination of downconversion. I used to work with UWB and the biggest difficulty I ran across was the regulatory issues, since the entire RF regulatory machine was built around frequency based, as opposed to time based modulations (though there are UWB methods that blur the lines more thoroughly)
Yes they are illegal. Any sign posted in the public right of way without a permit is illegal (Excepting, of course roadsigns and the like, at least in Austin, TX, it is, and I assume most other places). I pull up these signs and have only seen a tiny number of them with permits (which were pasted onto the back). This also includes political signs, real estate signs, lost animal signs, and garage sale signs. I've found that the real-estate signs that get put up on weekends (and taken down by the same folks, apparently) are a great source for angle-iron. They're known as 'bandit signs', and I've filled up a 3/4 ton truck on a Sunday morning, and seen no difference the next weekend. It is usually up to code enforcement to ticket the offenders, but they are usually out doing things that the city council (often bandit sign offenders themselves) deem more important.
Please don't take this as insulting (or trying to insult you- I truly, honestly want to help people make good circuits), but this is exactly the sort of ignorance that gets me frustrated! A blanket statement like that can get you in real trouble- while your signal may just be "20MHz", since you're talking about a clock signal, you've got harmonics and lots of them. It is those harmonics that get you into trouble- you can take that bitstream and look at it with a 20MHz scope and it will look *great*, but check it out with a 1GHz scope and it will look like an ungodly mess. Yes- it may work- but if it does, chalk that up to a good design from the Silicon manufacturer.
There is no magic frequency for which a PCB is good enough and a breadboard is overkill, unfortunately. It depends on what you're trying to do, the parts you're using, and the environment you are doing the design for.
There is a ton of cool stuff you can do, but when things don't work, have a back-up plan- and for me, that back-up plan is additional knowledge from sources I can trust, people I know, books, and then, way down the line, is slashdot...
A via is a connection from one side of the board to another. They add a complex resistance (or, in other words, impedance) to the trace, and in general, that slows down the edges of traces. It is mostly capacitance, but a via can also add inductance. Poor design causes excess ground bounce, which is a real problem for high speed/ (which ends up being) high current design. Ground bounce happens because anytime you have current flowing across a resistance (impedance), you get a voltage (Ohm's law).
If there is a resistance on your ground pin, that causes a voltage on the trace leading to the ground- if the resistance/impedance there is large enough, it is like adding a transient voltage in your ground line- which screws up the ground reference for your whole chip.
In summary, what this means, at high speeds, the traces on a board are no longer 0 ohm, 0 length wires- they are transmission lines, and have to be treated as such. Many people designing with the parts that go at these real high speeds do so in ignorance of high frequency design, and end up with really screwed up circuits and then they probe it with a 20MHz scope and don't see a problem- and then blame the parts that they put down, when it is their own really poor design and ignorant use of their own tools... ok, maybe I'm putting out some of my own frustrations, but design with high MIPS parts is definitely not trivial, and when you get a 'low cost' product, you can often get what you pay for- and quality is often seen in electronics by the lack of problems- and people don't laud the high quality of a product nearly as loud as they complain about the lack of quality.
Nothing until the beginning of August, 1995- a friend registered hazmat.com for me at the end of July, 1995 (and it was free). Tried to register the.net, but at that point, you couldn't register a.net unless you were an infrastructure provider.
Where is the signal strength analysis? Electromagnetic signals reduce in proportion to the the inverse of the square of the distance, and that is for the signals that are radiated into space-- energy broadcast into space is wasted if you're trying to broadcast to your local planet, so you intentionally try not to broadcast up. Given that, what sort of signal strength can we detect? Heck, the closest star is still more than a light year away- I just did a quick calculation- and man- the signal strength difference between 1m and 1 light year is over 300dB (If I did my calculations right). We have to do very special types of processing to detect GPS signals, and they are only a few thousand miles away.
Of course, that is assuming that "our way" communication by RF modulation is what the alien civilizations would use.
They should not block Wikipedia, for sure, but if the child gets something wrong from their research, they should be marked down since they didn't do their research properly. Even Encyclopedia Britannica can be wrong- if they find a discrepancy between two sources, they should be required to investigate additional sources until they at least gather a consensus, and properly attribute it. Making a single observation and declaring it the absolute truth is faulty science, no reason that online research should be any different.
This isn't an issue with the computer itself- (if there is a problem) it is a problem with the power supply- there shouldn't be anything above about 20V DC coming from the power supply itself. If the supply if double insulated (read no ground pin) there will always be a voltage between "ground" and the chassis of the computer- There is nothing magic about ground- it is just the common 0V reference, with enough insulation- it just doesn't matter. Seems to me that when you give someone a tool (VOM) and not enough understanding of electronics, you can create lots of hype...
Actually, it is pretty surprising how much current Gigabit takes- The output drives usually work in a current mode, and they draw 40mA per pair- since gigabit uses 4 pairs, that's 160mA on each end of a gigabit link. *But* the big difference is in what happens when the link is idling- 10mbit only puts through link test pulses, but 100Mbit and Gigabit both keep up idle patterns that are basically encoded strings of no information- this keeps both ends of the link ready to accept data- 10Mbit has to transmit a synchronization series of pulses to make sure both ends are clocking at the same rate. For 100 and gig, at least to the output drivers, they draw the same amount idling or transmitting at line-speed.
The biggest problem is that POE is limited to 13W at 48V- you'll have to have some sort of converter in there. I don't think that you would have much problem powering small scale things like APs and cameras, but it doesn't scale up very well.
There is little that can be said, other than just make stuff. Most components are cheap- find some local surplus place or just learn to pull parts off of old PCB boards. When it comes to the fundamentals, at this stage, make sure you understand Ohms law (V=I*R). Ohms law is behind *everything* in electronics, not just DC. AC makes it more complicated (with AC R is a "complex" value, otherwise termed as Z, or impedance, which is where capacitance and inductance come in). No matter what, the voltage is equal to the product of the current and impedance.
If you measure something and it doesn't make sense... most likely you didn't make some ground breaking discovery- it is probably a problem with your understanding of the circuit, or a limitation of your tool- A prime example of this is measuring with a scope- a scope has limited bandwidth- if you try to measure a 100 MHz signal with a 20 MHZ analog scope, you won't see anything- it isn't the circuit that is broken, it is a matter of not using the appropriate tool for the job. Digital scopes have their own issues- the biggest one being aliasing. Since the inputs usually have a much wider bandwidth than the sampling rate (with no anti-aliasing filters), you can get *really* confused.
If it doesn't make sense, find out why!
Getting an EE degree is a good way to learn about electronics, but frankly, just a part of the journey. I've seen way too many EEs that don't know which end of a soldering iron to grab. (I have a BSEE ('91), a MSEE ('97), electronics is a vocation and an avocation for me.) A degree, by itself, won't get you there- the best resource is a mentor (also known as an 'Elmer' for the ham radio types).
I'm not a Computer Scientist- I'm an EE- and I may be biased towards the engineering type courses, but I think some digital signal processing type courses would be incredibly useful (beyond just engineers). Of course, there are a whole bunch of prerequisites, including calculus, differential equations, signals, and probability/stochastic processes. Not every CS major is going to be working on making new OSes- there has to be some application processing going on, and if you are working on data derived from meatspace, DSP and all the prerequisites are vital.
There are lots of electrical engineers forced into programming because the Computer Science guys just don't have the math background- and what we often end up with is pretty poorly done code because the coursework behind the engineering degree is lots of math and relatively little code. What I'd really like to see is a combination of better code and better systems to run that code.
I was going to say something on the order of what you said- and I agree with you. Maybe I'm biased (but in a reasonable way). I'm a former employee of Dell. The place is cut throat, but they make good computers as inexpensively as possible. I'm glad I don't work there, but I still buy Dell computers and network hardware because they have good prices and good quality. Dell designs and builds a lot of its stuff, buys it from others when the price is right. What so many of the vocal slashdot-type crowd don't take into account is the costs beyond the physical hardware. Support is expensive, so it is in a company's best interest to make their parts appropriately reliable. Don't expect top of the line components in the $300 special- it just won't happen if the company wants to stay in business.
Dell, as a publicly traded company, has a responsibility to its shareholders. Not to the customer or the employee, but to the owners. There is value in not alienating a customer, but there are some customers that may just be too expensive. Don't think that people at Dell are unaware of open source and Linux- it is in use in the halls and the labs and the cubes. Dell doesn't write/port OSes. They do sell systems. They agressively collect the parts (hardware and software) put them together, test them, haggle the prices, and sell the system with support. For consumer level computers, Linux doesn't make economic sense. Why do I think that way? Because if it did, Dell would sell it. In the places where Linux does make sense (servers and workstations) Dell does pre-install Linux. Those customers know what they want and are willing to pay for it.
Testing and support are far more expensive than most people expect. Dell occupies a vital niche that many people aren't aware of- the computers they sell generally are released when the chipset is released- Dell has been instrumental in debugging the chipsets for Intel, which means they get to sell it before the other lower cost ("white box") manufacturers can push the price down to a narrow margin. But in that time, Dell has sold a *HUGE* volume, made their money, and moved on. In that time, they have been continuously debugging and improving the parts, which is shared with Intel (under NDA, of course), and Intel's (and the other chip manufacturers) parts get better. Because Dell (and the other Major OEMs) have invested so much in improving the parts and designs, the white box OEMs end up getting a very well debugged design that they can work their own magic upon (generally pushing the price down even further). They don't have to spend immense amounts of money to test the systems, because others did it for them.
I really do trust in the folks behind wikipedia- they want to keep the project going, but at a certain point, someone has to pay for this stuff.
Why not set up two servers with the same content- one supported wholly by donations (with no ads), the other supported by ads (a la adwords), give them different (but close) URLs and see how it works out? If the free server gets plenty of donations, they will be able to support more users/bandwidth, on the other hand, maybe the ad supported site will get more money and be able to support more users/bandwidth.
Overall, the most important piece is that the raw data be now *and forever* free to anyone that wants it. Can't the licensing be limited to preventing the forking of a proprietary (non-free) but publicly accessable database?
I've got some weird triggers for my asthma- like dishwasher detergent and dryer sheets- but sometimes there is no apparent cause- it happens at virtually any time of the year in varied circumstances. This makes me think that my asthma isn't 100% allergy related. The most controversial thing about the treatment that Dr. Mirkin recommends is the length of the treatment- something like 6 months to a year on a powerful antibiotic, even though symptoms may subside, to truly clear the infection, you have to maintain the dosage. It seems that the lungs are a particularly difficult area to treat.
I would love to be truly cured of this- It does interfere with my life, and the idea of suffocating to death because of asthma is absolutely terrifying. I've only had one episode where I felt my life was at risk, but it was enough not to go through it again. But the doctors throw up their hands and say 'learn to live with it.'
I suffer from "Adult Onset Asthma"- the first symptoms happened when I was about 27. Every doctor I've talked to about it wants me to get allergy shots, take antihisthamenes, and bronchodialators. At best, these things have just served to mask some of my symptoms. There is big business in maintainence medicines for asthma- keep treating the symptoms, and they are on your medicine for life. The only drug that was truly effective was an inhaler based medicine called Serevent. This medicine got pulled because of the "non-ozone friendly" propellant- at what looks like a time shortly before the patent was about to expire (and go generic). Right on the heels of that, came "Advair" - which is a mixture of the medicine that worked for me from Serevent, plus an anti-inflammatory (steroid- which I've taken, but don't help me much), with brand new patent protection.
On the other hand, there is a radio Doctor that I used to listen to, Dr. Gabe Mirkin that has preached for years about treating adult onset asthma with anti-biotics. As far as I'm aware, he's not an internist- but he does read a lot of medical journals with a doctor's eye, so he was one of the early ones to pick up on the work on ulcers and infection, and preach about that on his radio show. Unfortunately, I haven't been able to find any doctors that were willing to try and treat my Asthma with antibiotics. I can only hope that sometime before the asthma kills me, I at least get a shot at trying to cure this disease, rather than just playing catch-up with the symptoms.
N.B.: Dr. Mirkin was also one of the early people to preach about using Fen-Phen for weight loss. While it was effective for some, it could also be dangerous. I think this is the risk of any new treatment- but unless we take some risks, we will never have progress in medicine.
People buy Tivo- the box is theirs. Where are the people hacking stuff onto it? I've seen plenty of links/books based on hacking into the Tivo, but I can't remember any that involved totally replacing the whole OS. Can it be done? Has it been done?
Big monitors can display the higher resolutions- if you're powering up a machine that has its default video setting to 1600x1200- your 5 year old 15" monitor may not be able to display it- which leaves you without a display on a machine you're troubleshooting. In my last job, I had a really nice LCD (17") on my bench- it was great when it came to saving bench space, but it wouldn't display anything better than 1280x1024 and just kept a black screen (or a message that it couldn't display the image) if you tried to plug in a higher resolution. Which means... fiddling with the default resolution or finding the appropriate monitor and lugging it to your bench- both of which mean additional time.
I see your point- but keeping the disclosure of the flaw under wraps may be more effective at keeping the black hats out- in the short term. Ultimately, it seems that the Internet as a whole would be better off if the disclosure was kept away from the black hats until it is reported in the wild- which I would guess would be the responsibility of a trusted source (CERT?). Once it is reported and there is a way to stop it- hell yes, full disclosure, ASAP.
The problem I have with full, immediate disclosure is that it makes the flaw impossible to contain *before* it is fixed (and fully tested). Containment is important- because while there are conscientious admins out there- there are plenty that aren't.
Ultimately, I think the place we disagree is the extent of testing- from my experience, QA is vital- primarily because I want to make sure that new holes aren't opened up. It sounds like you are more willing to take the risk- just think about this- if they screwed it up the first time, what is to prevent them screwing up the fix?
If there is a way to block access to the vulnerable service without disclosing the flaw- that is by far the best- but ultimately knowledge (any knowledge) is the important fact in understanding the flaw. To keep the black hats out, we have to resort to security through obscurity for a time- it is overall a flawed model- but denial of information is still a powerful tool.
Ultimately, if you don't like the way that some organization does (or does not) disclose their flaws- you do have the option to not use their product. Part of their product is how they maintain and support it. I see that as the biggest flaw in open source- due to the licensing , if it is screwed up- it's all your fault- even if you try to sue, you've got a couple individuals , but a corporation- there can be big money there- and they need to protect it, so they have more incentive to make it right (lest they lose their stockholder's money). Kind of a screwed up system, but that's the system we have.
At the very least, I believe in full disclosure to the company that writes the software- but public disclosure opens up too many risks- yes, someone else may find it, but I really don't think that Microsoft purposely leaves out fixes- they have lots of fixes to put in, and they have to prioritize them. Yes, if it is public, it gets higher priority, but they have finite resources to investigate the fix, find it, fix it, and then test to make sure that they don't break anything else.
I think that what the open source community fails to realize is the huge amount of effort that goes into testing. I used to work for one of the big computer manufacturers- (rhymes with Hell), and the software that is released on a system (my experience is with servers) is usually frozen months in advance so that the different phases of test can pound on it, not just so that they can find errors, but so that they can characterize those errors. The fix for a critical error may be done in a day, but the testing may take weeks- to test with different hardware, system software, amount of RAM, HD, different processors... the list is long- but ultimately what they are trying to make sure is that a fix for one thing doesn't cause something else to break in a worse way. This is particularly important when you are maintaining code someone else wrote- you may not fully realize why it was done that way... until it is too late.
Unfortunately, the IP issues often force companies not to reveal what they are doing. Every single person I worked with was extremely conscientious about their work, they take flaws very seriously, but remember, their priorities are not the same as yours, and if you could see the scope of what they are working on, you might be able to better understand why their priorities are where they are. On the other hand, they don't know you from Adam, and you might just be one of those black hats- so they can't reveal the HUGE GAPING HOLE they just found, to show you that they really do care about the tiny (but significant) hole you found.
A bus is much more efficient per passenger mile than the SUV (or probably even the Prius that eco-mom drives). 30 students moved 10 miles (at say, 10 mpg) takes 1 gallon, move those same 30 students 10 miles in individual cars that get 50 mpg would take (30*10/50)=6 gallons of gas, or in other words, you would have to pack 5 kids in each 50mpg hybrid to match the transportation efficiency of the ugly yellow bus.
To be sold in the US, the laptop has to pass FCC certification- there are similar requirements for every other country. The FCC requires that emissions be below a certain level, so that they don't interfere with legitamate users of the airwaves- so there has been testing that has shown that the power level out is pretty low (usually in the microwatts or lower).
But the biggest reason why I wouldn't be concerned is simply the conservation of energy- all of the energy in the laptop is consumed some way- ultimately as some sort of EM radiation (RF out, light out of the display, and heat) Laptop makers are extremely concerned about battery life- if you were transmitting 40W of power as 2.4GHz RF- that's 40W of power that wouldn't be consumed by the CPU- and that much less total operational time while on the battery.
Slashdot Mirror
UWB is great, but it is just another form of modulation. The same principles apply to the older modulation techniques apply in the same way to UWB (such as a channel's carrying capacity at a certain bandwidth, dynamic range, error rate). It ain't magic, and doesn't have any mysterious abilities (some have been postulated, none have been proved). The only real advantage I see in it is that it can be a form of modulation that is time (rather than frequency) based, so it maps well with our most common computing paradigm (a common clock, IOW synchronous). Because of this, the hardware can be made simpler-- the elimination of downconversion.
I used to work with UWB and the biggest difficulty I ran across was the regulatory issues, since the entire RF regulatory machine was built around frequency based, as opposed to time based modulations (though there are UWB methods that blur the lines more thoroughly)
Yes they are illegal. Any sign posted in the public right of way without a permit is illegal (Excepting, of course roadsigns and the like, at least in Austin, TX, it is, and I assume most other places). I pull up these signs and have only seen a tiny number of them with permits (which were pasted onto the back). This also includes political signs, real estate signs, lost animal signs, and garage sale signs. I've found that the real-estate signs that get put up on weekends (and taken down by the same folks, apparently) are a great source for angle-iron. They're known as 'bandit signs', and I've filled up a 3/4 ton truck on a Sunday morning, and seen no difference the next weekend. It is usually up to code enforcement to ticket the offenders, but they are usually out doing things that the city council (often bandit sign offenders themselves) deem more important.
Please don't take this as insulting (or trying to insult you- I truly, honestly want to help people make good circuits), but this is exactly the sort of ignorance that gets me frustrated! A blanket statement like that can get you in real trouble- while your signal may just be "20MHz", since you're talking about a clock signal, you've got harmonics and lots of them. It is those harmonics that get you into trouble- you can take that bitstream and look at it with a 20MHz scope and it will look *great*, but check it out with a 1GHz scope and it will look like an ungodly mess. Yes- it may work- but if it does, chalk that up to a good design from the Silicon manufacturer.
There is no magic frequency for which a PCB is good enough and a breadboard is overkill, unfortunately. It depends on what you're trying to do, the parts you're using, and the environment you are doing the design for.
There is a ton of cool stuff you can do, but when things don't work, have a back-up plan- and for me, that back-up plan is additional knowledge from sources I can trust, people I know, books, and then, way down the line, is slashdot...
A via is a connection from one side of the board to another. They add a complex resistance (or, in other words, impedance) to the trace, and in general, that slows down the edges of traces. It is mostly capacitance, but a via can also add inductance. Poor design causes excess ground bounce, which is a real problem for high speed/ (which ends up being) high current design. Ground bounce happens because anytime you have current flowing across a resistance (impedance), you get a voltage (Ohm's law).
If there is a resistance on your ground pin, that causes a voltage on the trace leading to the ground- if the resistance/impedance there is large enough, it is like adding a transient voltage in your ground line- which screws up the ground reference for your whole chip.
In summary, what this means, at high speeds, the traces on a board are no longer 0 ohm, 0 length wires- they are transmission lines, and have to be treated as such. Many people designing with the parts that go at these real high speeds do so in ignorance of high frequency design, and end up with really screwed up circuits and then they probe it with a 20MHz scope and don't see a problem- and then blame the parts that they put down, when it is their own really poor design and ignorant use of their own tools... ok, maybe I'm putting out some of my own frustrations, but design with high MIPS parts is definitely not trivial, and when you get a 'low cost' product, you can often get what you pay for- and quality is often seen in electronics by the lack of problems- and people don't laud the high quality of a product nearly as loud as they complain about the lack of quality.
Nothing until the beginning of August, 1995- a friend registered hazmat.com for me at the end of July, 1995 (and it was free). Tried to register the .net, but at that point, you couldn't register a .net unless you were an infrastructure provider.
Where is the signal strength analysis? Electromagnetic signals reduce in proportion to the the inverse of the square of the distance, and that is for the signals that are radiated into space-- energy broadcast into space is wasted if you're trying to broadcast to your local planet, so you intentionally try not to broadcast up. Given that, what sort of signal strength can we detect? Heck, the closest star is still more than a light year away- I just did a quick calculation- and man- the signal strength difference between 1m and 1 light year is over 300dB (If I did my calculations right). We have to do very special types of processing to detect GPS signals, and they are only a few thousand miles away.
Of course, that is assuming that "our way" communication by RF modulation is what the alien civilizations would use.
Generally, to refer to something as dead, it must have first been alive.
They should not block Wikipedia, for sure, but if the child gets something wrong from their research, they should be marked down since they didn't do their research properly. Even Encyclopedia Britannica can be wrong- if they find a discrepancy between two sources, they should be required to investigate additional sources until they at least gather a consensus, and properly attribute it. Making a single observation and declaring it the absolute truth is faulty science, no reason that online research should be any different.
This isn't an issue with the computer itself- (if there is a problem) it is a problem with the power supply- there shouldn't be anything above about 20V DC coming from the power supply itself. If the supply if double insulated (read no ground pin) there will always be a voltage between "ground" and the chassis of the computer- There is nothing magic about ground- it is just the common 0V reference, with enough insulation- it just doesn't matter. Seems to me that when you give someone a tool (VOM) and not enough understanding of electronics, you can create lots of hype...
Actually, it is pretty surprising how much current Gigabit takes- The output drives usually work in a current mode, and they draw 40mA per pair- since gigabit uses 4 pairs, that's 160mA on each end of a gigabit link. *But* the big difference is in what happens when the link is idling- 10mbit only puts through link test pulses, but 100Mbit and Gigabit both keep up idle patterns that are basically encoded strings of no information- this keeps both ends of the link ready to accept data- 10Mbit has to transmit a synchronization series of pulses to make sure both ends are clocking at the same rate. For 100 and gig, at least to the output drivers, they draw the same amount idling or transmitting at line-speed.
The biggest problem is that POE is limited to 13W at 48V- you'll have to have some sort of converter in there. I don't think that you would have much problem powering small scale things like APs and cameras, but it doesn't scale up very well.
There is little that can be said, other than just make stuff. Most components are cheap- find some local surplus place or just learn to pull parts off of old PCB boards. When it comes to the fundamentals, at this stage, make sure you understand Ohms law (V=I*R). Ohms law is behind *everything* in electronics, not just DC. AC makes it more complicated (with AC R is a "complex" value, otherwise termed as Z, or impedance, which is where capacitance and inductance come in). No matter what, the voltage is equal to the product of the current and impedance.
If you measure something and it doesn't make sense... most likely you didn't make some ground breaking discovery- it is probably a problem with your understanding of the circuit, or a limitation of your tool- A prime example of this is measuring with a scope- a scope has limited bandwidth- if you try to measure a 100 MHz signal with a 20 MHZ analog scope, you won't see anything- it isn't the circuit that is broken, it is a matter of not using the appropriate tool for the job. Digital scopes have their own issues- the biggest one being aliasing. Since the inputs usually have a much wider bandwidth than the sampling rate (with no anti-aliasing filters), you can get *really* confused.
If it doesn't make sense, find out why!
Getting an EE degree is a good way to learn about electronics, but frankly, just a part of the journey. I've seen way too many EEs that don't know which end of a soldering iron to grab. (I have a BSEE ('91), a MSEE ('97), electronics is a vocation and an avocation for me.) A degree, by itself, won't get you there- the best resource is a mentor (also known as an 'Elmer' for the ham radio types).
I'm not a Computer Scientist- I'm an EE- and I may be biased towards the engineering type courses, but I think some digital signal processing type courses would be incredibly useful (beyond just engineers). Of course, there are a whole bunch of prerequisites, including calculus, differential equations, signals, and probability/stochastic processes. Not every CS major is going to be working on making new OSes- there has to be some application processing going on, and if you are working on data derived from meatspace, DSP and all the prerequisites are vital.
There are lots of electrical engineers forced into programming because the Computer Science guys just don't have the math background- and what we often end up with is pretty poorly done code because the coursework behind the engineering degree is lots of math and relatively little code. What I'd really like to see is a combination of better code and better systems to run that code.
Dell, as a publicly traded company, has a responsibility to its shareholders. Not to the customer or the employee, but to the owners. There is value in not alienating a customer, but there are some customers that may just be too expensive. Don't think that people at Dell are unaware of open source and Linux- it is in use in the halls and the labs and the cubes. Dell doesn't write/port OSes. They do sell systems. They agressively collect the parts (hardware and software) put them together, test them, haggle the prices, and sell the system with support. For consumer level computers, Linux doesn't make economic sense. Why do I think that way? Because if it did, Dell would sell it. In the places where Linux does make sense (servers and workstations) Dell does pre-install Linux. Those customers know what they want and are willing to pay for it.
Testing and support are far more expensive than most people expect. Dell occupies a vital niche that many people aren't aware of- the computers they sell generally are released when the chipset is released- Dell has been instrumental in debugging the chipsets for Intel, which means they get to sell it before the other lower cost ("white box") manufacturers can push the price down to a narrow margin. But in that time, Dell has sold a *HUGE* volume, made their money, and moved on. In that time, they have been continuously debugging and improving the parts, which is shared with Intel (under NDA, of course), and Intel's (and the other chip manufacturers) parts get better. Because Dell (and the other Major OEMs) have invested so much in improving the parts and designs, the white box OEMs end up getting a very well debugged design that they can work their own magic upon (generally pushing the price down even further). They don't have to spend immense amounts of money to test the systems, because others did it for them.
> Donations usually don't cut it. People say a lot of things, but don't follow through...
At least if there is an alternate ad supported site, it still exists- it doesn't die an unglorious death due to non-payment of bandwidth fees.
Why not set up two servers with the same content- one supported wholly by donations (with no ads), the other supported by ads (a la adwords), give them different (but close) URLs and see how it works out? If the free server gets plenty of donations, they will be able to support more users/bandwidth, on the other hand, maybe the ad supported site will get more money and be able to support more users/bandwidth.
Overall, the most important piece is that the raw data be now *and forever* free to anyone that wants it. Can't the licensing be limited to preventing the forking of a proprietary (non-free) but publicly accessable database?
I would love to be truly cured of this- It does interfere with my life, and the idea of suffocating to death because of asthma is absolutely terrifying. I've only had one episode where I felt my life was at risk, but it was enough not to go through it again. But the doctors throw up their hands and say 'learn to live with it.'
On the other hand, there is a radio Doctor that I used to listen to, Dr. Gabe Mirkin that has preached for years about treating adult onset asthma with anti-biotics. As far as I'm aware, he's not an internist- but he does read a lot of medical journals with a doctor's eye, so he was one of the early ones to pick up on the work on ulcers and infection, and preach about that on his radio show. Unfortunately, I haven't been able to find any doctors that were willing to try and treat my Asthma with antibiotics. I can only hope that sometime before the asthma kills me, I at least get a shot at trying to cure this disease, rather than just playing catch-up with the symptoms.
N.B.: Dr. Mirkin was also one of the early people to preach about using Fen-Phen for weight loss. While it was effective for some, it could also be dangerous. I think this is the risk of any new treatment- but unless we take some risks, we will never have progress in medicine.
Austin Robot Technology's Entry is an Isuzu Vehicross based robot named Marvin.
People buy Tivo- the box is theirs. Where are the people hacking stuff onto it? I've seen plenty of links/books based on hacking into the Tivo, but I can't remember any that involved totally replacing the whole OS. Can it be done? Has it been done?
Big monitors can display the higher resolutions- if you're powering up a machine that has its default video setting to 1600x1200- your 5 year old 15" monitor may not be able to display it- which leaves you without a display on a machine you're troubleshooting. In my last job, I had a really nice LCD (17") on my bench- it was great when it came to saving bench space, but it wouldn't display anything better than 1280x1024 and just kept a black screen (or a message that it couldn't display the image) if you tried to plug in a higher resolution. Which means... fiddling with the default resolution or finding the appropriate monitor and lugging it to your bench- both of which mean additional time.
I see your point- but keeping the disclosure of the flaw under wraps may be more effective at keeping the black hats out- in the short term. Ultimately, it seems that the Internet as a whole would be better off if the disclosure was kept away from the black hats until it is reported in the wild- which I would guess would be the responsibility of a trusted source (CERT?). Once it is reported and there is a way to stop it- hell yes, full disclosure, ASAP.
The problem I have with full, immediate disclosure is that it makes the flaw impossible to contain *before* it is fixed (and fully tested). Containment is important- because while there are conscientious admins out there- there are plenty that aren't.
Ultimately, I think the place we disagree is the extent of testing- from my experience, QA is vital- primarily because I want to make sure that new holes aren't opened up. It sounds like you are more willing to take the risk- just think about this- if they screwed it up the first time, what is to prevent them screwing up the fix?
If there is a way to block access to the vulnerable service without disclosing the flaw- that is by far the best- but ultimately knowledge (any knowledge) is the important fact in understanding the flaw. To keep the black hats out, we have to resort to security through obscurity for a time- it is overall a flawed model- but denial of information is still a powerful tool.
Ultimately, if you don't like the way that some organization does (or does not) disclose their flaws- you do have the option to not use their product. Part of their product is how they maintain and support it. I see that as the biggest flaw in open source- due to the licensing , if it is screwed up- it's all your fault- even if you try to sue, you've got a couple individuals , but a corporation- there can be big money there- and they need to protect it, so they have more incentive to make it right (lest they lose their stockholder's money). Kind of a screwed up system, but that's the system we have.
At the very least, I believe in full disclosure to the company that writes the software- but public disclosure opens up too many risks- yes, someone else may find it, but I really don't think that Microsoft purposely leaves out fixes- they have lots of fixes to put in, and they have to prioritize them. Yes, if it is public, it gets higher priority, but they have finite resources to investigate the fix, find it, fix it, and then test to make sure that they don't break anything else.
I think that what the open source community fails to realize is the huge amount of effort that goes into testing. I used to work for one of the big computer manufacturers- (rhymes with Hell), and the software that is released on a system (my experience is with servers) is usually frozen months in advance so that the different phases of test can pound on it, not just so that they can find errors, but so that they can characterize those errors. The fix for a critical error may be done in a day, but the testing may take weeks- to test with different hardware, system software, amount of RAM, HD, different processors... the list is long- but ultimately what they are trying to make sure is that a fix for one thing doesn't cause something else to break in a worse way. This is particularly important when you are maintaining code someone else wrote- you may not fully realize why it was done that way... until it is too late.
Unfortunately, the IP issues often force companies not to reveal what they are doing. Every single person I worked with was extremely conscientious about their work, they take flaws very seriously, but remember, their priorities are not the same as yours, and if you could see the scope of what they are working on, you might be able to better understand why their priorities are where they are. On the other hand, they don't know you from Adam, and you might just be one of those black hats- so they can't reveal the HUGE GAPING HOLE they just found, to show you that they really do care about the tiny (but significant) hole you found.
A bus is much more efficient per passenger mile than the SUV (or probably even the Prius that eco-mom drives). 30 students moved 10 miles (at say, 10 mpg) takes 1 gallon, move those same 30 students 10 miles in individual cars that get 50 mpg would take (30*10/50)=6 gallons of gas, or in other words, you would have to pack 5 kids in each 50mpg hybrid to match the transportation efficiency of the ugly yellow bus.
To be sold in the US, the laptop has to pass FCC certification- there are similar requirements for every other country. The FCC requires that emissions be below a certain level, so that they don't interfere with legitamate users of the airwaves- so there has been testing that has shown that the power level out is pretty low (usually in the microwatts or lower).
But the biggest reason why I wouldn't be concerned is simply the conservation of energy- all of the energy in the laptop is consumed some way- ultimately as some sort of EM radiation (RF out, light out of the display, and heat) Laptop makers are extremely concerned about battery life- if you were transmitting 40W of power as 2.4GHz RF- that's 40W of power that wouldn't be consumed by the CPU- and that much less total operational time while on the battery.