I don't work in the black world, but the rest of the military takes decades to introduce or retire airframes. There are plenty of 70's-era airframes out there, and even the Stealth Fighter and Bomber (which I think of as fairly 'modern' designs) are 80's babies. I don't there's a really awesome 'popular science speculation worthy' plane out there, unless it is a UAV (where strides probably have been made).
Keep in mind too that active war (gulf wars I and II) is not good for military R&D because all that funding is going toward troop supplies and more copies of old stuff. Cold war is better for this, though I suppose terrorism works much the same way. DHS is probably making out like bandits...
You double-click the icon, you get music or you don't; If you didn't, it failed. You can research why it failed, it might even be easy to research, but it already failed.
Amen! I've worked as a physicist and engineer. I like to think I know quite a bit about the use of computers, and I certainly know how to use google and message boards. That doesn't mean I want to, or will willingly subject myself to that frustration. Especially now that I have a technical job with technical problems to solve, I don't wan't to waste my time troubleshooting the tool (a computer), or even worse, spend my free time at home troubleshooting something that should be fun (playing a video, mp3, game, etc). I can't imagine how much more frustrating these things would be for people who don't already have technical aptitude and interest.
Heck, I get angry just when the first thing I try doesn't work. For example, I was working with a diagramming program today. I expect that in most object-based drawing and layout programs I can select several items, right-click on one of them, and have a pop-up menu appear which allows me to group, ungroup, and align those objects. This tool chose to break convention and hide these commands somplace else. Argh! I hate fishing through menus.
The parent is right. LaTeX is largely unknown outside of Mathematics, Computer Science, and Physics. Even in bio- and chem- MS Word is the editor of choice (and the format journals accept submissions in). Sometimes expensive bibliographic management tools like EndNote are involved, but it is always Word underneath.
I was a physics major in school, and I thought LaTeX was great. I've since also learned how to properly use Word (with style sheets, autonumbering figures, etc.) and I have to admit Word is just not as bad as TeXperts would have you believe. It has the HUGE advantage too of being accessible and editable by almost anyone in the world, not just people who were math/comp/phys students.
Face it... and I can't imagine anyone on slashdot doesn't realize this -- Mathematicians, Physicists, and Computer Scientists are the odd ones, diverging wildly from the rest of society on every conceivable physical, intellectual, or social measure, including in their choice of tools.
I recently set up a computer for my sister. I only had a service pack 1 CD.
1. Install windows SP1; 2. Install motherboard, video card, DVD-RW, etc. Drivers; reboot. 3. Install wireless card and driver and reboot. 4. Download and install gazillions of patches for SP1, requiring one or two reboots, before even being allowed 5. To Download SP2, which installs by no means quickly; 6. Only now are we up to the topic of this article. Downloading a mess of updates, with repeated reboots. 7. Cleanup: going through the system, ripping out unwanted stuff like outlook express, messenger, etc. 8. Installing firefox, office, antivirus tools, etc.; running a registry cleaner (crapcleaner) to remove references to the stuff I uninstalled.
It took basically all day. I was doing other things while waiting, but it was not fun.
Last I checked, most genre fiction (including most of sci fi) is crap. I wouldn't normally include LotR in that category, but I see what you're saying. LotR, Narnia, Pan's Labrynth, Spiderwick, etc... it does seem to be a bit much! Of course, one could say the same thing about comic book movies.
As I wondered on another thread: What is this fascination with airports? Why don't the terrorists just blow up a mall or grocery store somewhere? There'd be no security to speak of, no need for identification, and it would get people in a more 'everyday' environment, which is much more personal than flying (something many of us probably don't do every day, or even every year).
Alright. I'll throw you a few bones here, about why our perspective might be different.
First: I'm young (or at least think I am): 27. I didn't fly for the first time until after 9/11, so I have no idea what pre-9/11 security was like. I'm also, by personality, very patient in queues, which no doubt annoys all the drivers around me now that I've moved to New Jersey. I will say I like traveling by train much better, though, especially at the smaller stations that only have platforms and not terminals. Walk up. Train stops, within minutes of schedule. You get on. Seconds later, train starts moving. Very nice.
Nine-eleven happened when I was in college, and at the time I got quite a bit worked up over the government's response. I'm still worked up about many parts of it, in particular the conflation of 9/11 and Iraq, and the president's use of the word 'crusade' in a public speech. I think kind of insensitivity and carelessness could and should get you fired from most jobs. The fear that the US would become some sort of soft-core police state never really materialized, though (at least on US soil). With the exception of the blogs (not credible) and a few nationally publicized stories, I haven't heard of actual, real-world people running afoul of post-9/11 bureaucracy, with one exception: foreign researchers studying in the US were having delays in their re-entry visas after visiting their homes on holiday. Don't get me wrong, that's very bad for America, but no was honestly surprised. My colleagues from Iran, Pakistan, and China chose to take their holiday here instead until the next year (when things were better straightened out).
But I'm probably different from you in other ways as well. For one, I use my credit card for every purchase I make (excepting vending machines and monthly rent). Though I find it disturbing the amount of information they (the credit card companies) collect, the convenience far out-weighs that concern. For another, I work for a government contractor. I've already had to open my life to much more exposure than I would have initially thought myself willing. The experience and 'timeliness' of the process taught me though that the government is really too inefficient and apathetic to do anything with its information. I'm actually more concerned about the credit card companies and insurance companies, and they at least have a market incentive to keep my data private.
What is freedom, though? Maybe I don't push the boundaries enough to run into the problems, and I'm just not being imaginative enough. I can travel anywhere I want in the US without anyone's permission. I can live anywhere I can afford the property, and work anywhere I am qualified. I can say or write whatever I want, especially on line. I don't have to pretend to like politicians. I can attend church or not. What freedom have I really lost?
What the terrorists want is to disrupt our lives, and cause fear. They have succeeded beyond their wildest dreams. We have already lost the "war."
Whoa! Has your life really been disrupted? Are you really afraid? Maybe I'm in the minority here, but my life has not been disrupted at all by 9/11 or any of the policies that have followed. To be honest, I'm not even sure the war has affected my life at all, except in the abstract economic sense, or the empathy for the fallen I feel when I hear their names read at church. I'd like to think I'm more globally-conscious and active than that, but the truth is it is really hard to think anything special or unusual is going on when it impacts my life so little. Maybe I should watch more TV news.
I've never found the security procedures at airports to be that frustrating -- unnecessary or misguided perhaps, but nothing worth getting angry about. Yeah, if my laptop were confiscated, I'd be annoyed, but I doubt that is happening with any frequency. Heck, if we're talking personal anecdotes and fringe cases in this thread (what else is slashdot about?), I'd say my experience has been the opposite. For my employer I've carried defense system components in my carry-on and I've avoided having them inspected just be politely indicating they were fragile.
As far as fear goes... Who honestly is afraid of a terrorist attack? Maybe people in NYC, who had to live through it, god bless them, but everyone else knows the chance of being hurt in a US terrorist attack is minuscule -- partly thanks law enforcement, don't think I'm ungrateful. At the very least, it's not something I ever have to think about..
Unless you want to make people afraid of flying in particular. I'm not sure what strategic purpose that would serve.
Think about why terrorism has the word terror in it. That might make things clearer.
I wasn't clear. I was questioning why it would be worth to make people afraid of traveling by plane when you could launch a more general campaign on the ground. Why would you want to make people afraid of flying in particular when you could make them afraid of just existing in the US?
Those are the shoulder-launched missiles of Russian and Chinese fame.
Hm, the first name that comes to mind is "Stinger". Not exactly Russian or Chinese.
Ok. I'll take that correction. Maybe Stingers are more famous. I tend to hear more about 'russian/chinese arms that have slipped out of the former USSR/China'. But you're right, it's always stingers on TV, in books, and computer games.
What you are talking about I think are 'manpads' - 'man portable air defense systems'. Those are the shoulder-launched missiles of Russian and Chinese fame. But if you're a terrorist, and already in the US, why not just blow something else up? As the grandfather poster suggested, if you just want to kill people, there are far easier ways, especially if you are already on the ground in the target country. Unless you want to make people afraid of flying in particular. I'm not sure what strategic purpose that would serve.
I thought part of the argument in the article was that even inspiration that appears to come in flashes has its genesis in a serious, time-intensive committment -- e.g. staying literate in your field and others from which you draw inspiration, spending time thinking about the problem, learning how to recognize a good idea when you see it, etc.
I don't think the article is claiming that problem-solving-by-flash never happens, but that the public perception of that style ignores the amount of work involved a) in getting yourself to a place where the flash of inspiration is possible and b) the work to implement an idea.
There is no and never will be (in the foreseeable future) a substitute for printed paper books.
That's a ridiculous thing to say. Haven't we learned using words like 'never' and 'always' is dangerous? I heard an editor from the New York Times say the same thing about printed newspapers not a week ago, and he's already wrong. Maybe there will still be a market for books indefinitely, but I doubt it will because there is a lack of replacements.
Most of the advantages of books that I can see: 1. Easier to read because of higher resolution, contrast, reflective vs. backlit display, higher quality typography, etc. 2. Don't depend on batteries or proximity to civilization. 3. Are a durable, physical good. 4. Have a re-sale market 5. Have an old-timey 'aesthetic' that some people enjoy.
However...
1. Just a question of technology; already progress is being made. 2. Hasn't stopped ipod. 3. Hasn't stopped online music sales or online piracy. 4. Likewise. Many people apparently don't care about this. 5. Yes, and there is a market for LPs and turntables. But not because there isn't a replacement.
Modern displays have decent color, but as long as we are limiting ourselves to red / green / blue color sources, this will always be distinguishable from real (real cyan is not a 50/50 mixture of blue and green light, it is a single wavelength between the two).
Well, there's some refining to do to be sure, but the human eye is not a laboratory spectrometer. We have a finite number of types of color receptors that have their own sensitivity curves. You don't need to replicate every wavelength on the spectrum to replicate reality; you only need to stimulate the eye's color receptors to the same degree (and in the same ratios) that the reality does. That's why RGB displays work at all. Now, with current technology, and the current standards, RGB only covers a subset of the human-perceivable color space. But that's not to say it is impossible to do so with only a few color sources.
It depends where you are. I've found turning signal use drops at both ends of the population-density spectrum. That is, in very rural areas, you see poor signal useage, and in very urban/populated areas, you see poor signal useage. I understand getting lazy about your signaling if you drive where you only encounter another vehicle once every few miles, but I don't understand the jack-arsery of... oh, North New Jersey drivers, for example.
IR is absorbed by water. It won't specifically damage your retina. A high power beam might, however, burn up your eyeballs, and/or body. It would just happen from the outside in.
On the other hand, the sort of personal disclosure we see on facebook may grow into a cultural, society-wide phenomenon. Presumably most people are concerned about information disclosure because of consequences of that disclosure. If there are few consequences, how many people will care? Sure, the HR director who hired me probably looked for my facebook page. But I came across his facebook page entirely by accident, and his is way more revealing of his personal life than mine is. Once the college students of today rise to power, I think personal internet disclosure will be more socially acceptable.
The FBI's behavior analysis unit, or whatever it is called, put together some documents on predicting school shootings and the like. Though there is some good advice in there, I couldn't help but read a lot the profiles of shooters as 'profiles of adolescents.'
There's a lot of people who are little bit wacky, especially when teenagers, who are not actually dangerously wacky. Being angry, or fascinated with death, or interested in fringe groups, or being emotionally unstable in general, etc., are pretty common teenager traits.
Normally if you are surfing slashdot, e-bay, google, yahoo, and other popular sites you wont end up with worms and malware on your computer.
Indeed. This is what I tell people whenever I am asked to clean their computers: You don't get viruses from Disney.com.
I've run windows for years without spyware or virus problems (though I do have zone alarm and AVG should my arrogance bite me). But I don't surf dodgy sites, or install random executables on my computer.
I've rarely found things cheaper on ebay than I could elsewhere, especially things like electronics which other people want (high demand) and don't know how to shop for. As you said, ebay only works if
1. You are bidding on a rare item that you simply can't find elsewhere 2. You are rare person bidding on an item no one else cares about. (essentially what you're hoping for in #2 in the parent post)
Mind you, this covers plenty of circumstances, but you're leaving out a lot of people: 1. People who enjoy ebay's search features. Maybe it is more convenient, even if it isn't cheaper. 2. People who have heard ebay is a good place to get cheap stuff and don't investigate whether there's a way to get cheaper stuff. 3. People who like the visceral pleasure of winning an auction or 'getting a deal'.
I agree, advertising doesn't distract the 'rational ebay user' demographic, who has already considered all non-auction retail venues before placing a bid. But it might distract people who are unfamiliar with the alternatives.
Look for my earlier post with the links. I think they are using a system similar to, if not identical to, this 'dtec' or 'dted' system produced by a company in a UK.
That system uses 1550nm telecommunications band light, which passes well enough through glass, but is absorbed by human skin. The UK system looks for dark areas which match certain size/shape limits that qualify as likely human faces.
I would be interested in knowing what wavelengths they are using since I am sure anything close to the midwave will be blocked by the car's windows and there won't be much blackbody radiation emitted in the near IR.
Hmmm. I would be interested too. (googles...)
A similar product uses 1550nm light. Fiber telecommunications band. Still near IR. I figured it had to be something like that to keep the laser costs down.
There's a theory, which may or may not be correct, but which is popularly credited with fixing New York City. It goes something like:
Vigorously enforcing minor but ubiquitous and highly visible crimes (turnstile jumping, graffiti, etc.) eventually causes a societal shift whereby more serious but less visible crimes are reduced. I think it was a 'tipping point' theory or somesuch.
Anyway, I've never seen anyone arrested for not paying on a train. I've seen people offered a chance to buy a ticket. When they refused, they were thrown off at the next stop. Maybe a repeat offender might get the cops called, I don't know.
Slashdot Mirror
I don't work in the black world, but the rest of the military takes decades to introduce or retire airframes. There are plenty of 70's-era airframes out there, and even the Stealth Fighter and Bomber (which I think of as fairly 'modern' designs) are 80's babies. I don't there's a really awesome 'popular science speculation worthy' plane out there, unless it is a UAV (where strides probably have been made). Keep in mind too that active war (gulf wars I and II) is not good for military R&D because all that funding is going toward troop supplies and more copies of old stuff. Cold war is better for this, though I suppose terrorism works much the same way. DHS is probably making out like bandits...
The parent is right. LaTeX is largely unknown outside of Mathematics, Computer Science, and Physics. Even in bio- and chem- MS Word is the editor of choice (and the format journals accept submissions in). Sometimes expensive bibliographic management tools like EndNote are involved, but it is always Word underneath.
I was a physics major in school, and I thought LaTeX was great. I've since also learned how to properly use Word (with style sheets, autonumbering figures, etc.) and I have to admit Word is just not as bad as TeXperts would have you believe. It has the HUGE advantage too of being accessible and editable by almost anyone in the world, not just people who were math/comp/phys students.
Face it... and I can't imagine anyone on slashdot doesn't realize this -- Mathematicians, Physicists, and Computer Scientists are the odd ones, diverging wildly from the rest of society on every conceivable physical, intellectual, or social measure, including in their choice of tools.
I hope he just wasn't familiar with the acronym.
I can't believe I'm seeing what is essentially relationship advice on slashdot.
If you want to talk painful...
I recently set up a computer for my sister. I only had a service pack 1 CD.
1. Install windows SP1;
2. Install motherboard, video card, DVD-RW, etc. Drivers; reboot.
3. Install wireless card and driver and reboot.
4. Download and install gazillions of patches for SP1, requiring one or two reboots, before even being allowed
5. To Download SP2, which installs by no means quickly;
6. Only now are we up to the topic of this article. Downloading a mess of updates, with repeated reboots.
7. Cleanup: going through the system, ripping out unwanted stuff like outlook express, messenger, etc.
8. Installing firefox, office, antivirus tools, etc.; running a registry cleaner (crapcleaner) to remove references to the stuff I uninstalled.
It took basically all day. I was doing other things while waiting, but it was not fun.
Last I checked, most genre fiction (including most of sci fi) is crap. I wouldn't normally include LotR in that category, but I see what you're saying. LotR, Narnia, Pan's Labrynth, Spiderwick, etc... it does seem to be a bit much! Of course, one could say the same thing about comic book movies.
As I wondered on another thread: What is this fascination with airports? Why don't the terrorists just blow up a mall or grocery store somewhere? There'd be no security to speak of, no need for identification, and it would get people in a more 'everyday' environment, which is much more personal than flying (something many of us probably don't do every day, or even every year).
Alright. I'll throw you a few bones here, about why our perspective might be different.
First: I'm young (or at least think I am): 27. I didn't fly for the first time until after 9/11, so I have no idea what pre-9/11 security was like. I'm also, by personality, very patient in queues, which no doubt annoys all the drivers around me now that I've moved to New Jersey. I will say I like traveling by train much better, though, especially at the smaller stations that only have platforms and not terminals. Walk up. Train stops, within minutes of schedule. You get on. Seconds later, train starts moving. Very nice.
Nine-eleven happened when I was in college, and at the time I got quite a bit worked up over the government's response. I'm still worked up about many parts of it, in particular the conflation of 9/11 and Iraq, and the president's use of the word 'crusade' in a public speech. I think kind of insensitivity and carelessness could and should get you fired from most jobs. The fear that the US would become some sort of soft-core police state never really materialized, though (at least on US soil). With the exception of the blogs (not credible) and a few nationally publicized stories, I haven't heard of actual, real-world people running afoul of post-9/11 bureaucracy, with one exception: foreign researchers studying in the US were having delays in their re-entry visas after visiting their homes on holiday. Don't get me wrong, that's very bad for America, but no was honestly surprised. My colleagues from Iran, Pakistan, and China chose to take their holiday here instead until the next year (when things were better straightened out).
But I'm probably different from you in other ways as well. For one, I use my credit card for every purchase I make (excepting vending machines and monthly rent). Though I find it disturbing the amount of information they (the credit card companies) collect, the convenience far out-weighs that concern. For another, I work for a government contractor. I've already had to open my life to much more exposure than I would have initially thought myself willing. The experience and 'timeliness' of the process taught me though that the government is really too inefficient and apathetic to do anything with its information. I'm actually more concerned about the credit card companies and insurance companies, and they at least have a market incentive to keep my data private.
What is freedom, though? Maybe I don't push the boundaries enough to run into the problems, and I'm just not being imaginative enough. I can travel anywhere I want in the US without anyone's permission. I can live anywhere I can afford the property, and work anywhere I am qualified. I can say or write whatever I want, especially on line. I don't have to pretend to like politicians. I can attend church or not. What freedom have I really lost?
Whoa! Has your life really been disrupted? Are you really afraid? Maybe I'm in the minority here, but my life has not been disrupted at all by 9/11 or any of the policies that have followed. To be honest, I'm not even sure the war has affected my life at all, except in the abstract economic sense, or the empathy for the fallen I feel when I hear their names read at church. I'd like to think I'm more globally-conscious and active than that, but the truth is it is really hard to think anything special or unusual is going on when it impacts my life so little. Maybe I should watch more TV news.
I've never found the security procedures at airports to be that frustrating -- unnecessary or misguided perhaps, but nothing worth getting angry about. Yeah, if my laptop were confiscated, I'd be annoyed, but I doubt that is happening with any frequency. Heck, if we're talking personal anecdotes and fringe cases in this thread (what else is slashdot about?), I'd say my experience has been the opposite. For my employer I've carried defense system components in my carry-on and I've avoided having them inspected just be politely indicating they were fragile.
As far as fear goes... Who honestly is afraid of a terrorist attack? Maybe people in NYC, who had to live through it, god bless them, but everyone else knows the chance of being hurt in a US terrorist attack is minuscule -- partly thanks law enforcement, don't think I'm ungrateful. At the very least, it's not something I ever have to think about..
I wasn't clear. I was questioning why it would be worth to make people afraid of traveling by plane when you could launch a more general campaign on the ground. Why would you want to make people afraid of flying in particular when you could make them afraid of just existing in the US?
Ok. I'll take that correction. Maybe Stingers are more famous. I tend to hear more about 'russian/chinese arms that have slipped out of the former USSR/China'. But you're right, it's always stingers on TV, in books, and computer games.
What you are talking about I think are 'manpads' - 'man portable air defense systems'. Those are the shoulder-launched missiles of Russian and Chinese fame. But if you're a terrorist, and already in the US, why not just blow something else up? As the grandfather poster suggested, if you just want to kill people, there are far easier ways, especially if you are already on the ground in the target country. Unless you want to make people afraid of flying in particular. I'm not sure what strategic purpose that would serve.
I thought part of the argument in the article was that even inspiration that appears to come in flashes has its genesis in a serious, time-intensive committment -- e.g. staying literate in your field and others from which you draw inspiration, spending time thinking about the problem, learning how to recognize a good idea when you see it, etc.
I don't think the article is claiming that problem-solving-by-flash never happens, but that the public perception of that style ignores the amount of work involved a) in getting yourself to a place where the flash of inspiration is possible and b) the work to implement an idea.
That's a ridiculous thing to say. Haven't we learned using words like 'never' and 'always' is dangerous? I heard an editor from the New York Times say the same thing about printed newspapers not a week ago, and he's already wrong. Maybe there will still be a market for books indefinitely, but I doubt it will because there is a lack of replacements.
Most of the advantages of books that I can see:
1. Easier to read because of higher resolution, contrast, reflective vs. backlit display, higher quality typography, etc.
2. Don't depend on batteries or proximity to civilization.
3. Are a durable, physical good.
4. Have a re-sale market
5. Have an old-timey 'aesthetic' that some people enjoy.
However...
1. Just a question of technology; already progress is being made.
2. Hasn't stopped ipod.
3. Hasn't stopped online music sales or online piracy.
4. Likewise. Many people apparently don't care about this.
5. Yes, and there is a market for LPs and turntables. But not because there isn't a replacement.
There's a very obvious reason for that, you know...
Well, there's some refining to do to be sure, but the human eye is not a laboratory spectrometer. We have a finite number of types of color receptors that have their own sensitivity curves. You don't need to replicate every wavelength on the spectrum to replicate reality; you only need to stimulate the eye's color receptors to the same degree (and in the same ratios) that the reality does. That's why RGB displays work at all. Now, with current technology, and the current standards, RGB only covers a subset of the human-perceivable color space. But that's not to say it is impossible to do so with only a few color sources.
It depends where you are. I've found turning signal use drops at both ends of the population-density spectrum. That is, in very rural areas, you see poor signal useage, and in very urban/populated areas, you see poor signal useage. I understand getting lazy about your signaling if you drive where you only encounter another vehicle once every few miles, but I don't understand the jack-arsery of... oh, North New Jersey drivers, for example.
IR is absorbed by water. It won't specifically damage your retina. A high power beam might, however, burn up your eyeballs, and/or body. It would just happen from the outside in.
On the other hand, the sort of personal disclosure we see on facebook may grow into a cultural, society-wide phenomenon. Presumably most people are concerned about information disclosure because of consequences of that disclosure. If there are few consequences, how many people will care? Sure, the HR director who hired me probably looked for my facebook page. But I came across his facebook page entirely by accident, and his is way more revealing of his personal life than mine is. Once the college students of today rise to power, I think personal internet disclosure will be more socially acceptable.
The FBI's behavior analysis unit, or whatever it is called, put together some documents on predicting school shootings and the like. Though there is some good advice in there, I couldn't help but read a lot the profiles of shooters as 'profiles of adolescents.'
There's a lot of people who are little bit wacky, especially when teenagers, who are not actually dangerously wacky. Being angry, or fascinated with death, or interested in fringe groups, or being emotionally unstable in general, etc., are pretty common teenager traits.
Indeed. This is what I tell people whenever I am asked to clean their computers: You don't get viruses from Disney.com.
I've run windows for years without spyware or virus problems (though I do have zone alarm and AVG should my arrogance bite me). But I don't surf dodgy sites, or install random executables on my computer.
I've rarely found things cheaper on ebay than I could elsewhere, especially things like electronics which other people want (high demand) and don't know how to shop for. As you said, ebay only works if
1. You are bidding on a rare item that you simply can't find elsewhere
2. You are rare person bidding on an item no one else cares about. (essentially what you're hoping for in #2 in the parent post)
Mind you, this covers plenty of circumstances, but you're leaving out a lot of people:
1. People who enjoy ebay's search features. Maybe it is more convenient, even if it isn't cheaper.
2. People who have heard ebay is a good place to get cheap stuff and don't investigate whether there's a way to get cheaper stuff.
3. People who like the visceral pleasure of winning an auction or 'getting a deal'.
I agree, advertising doesn't distract the 'rational ebay user' demographic, who has already considered all non-auction retail venues before placing a bid. But it might distract people who are unfamiliar with the alternatives.
Look for my earlier post with the links. I think they are using a system similar to, if not identical to, this 'dtec' or 'dted' system produced by a company in a UK.
That system uses 1550nm telecommunications band light, which passes well enough through glass, but is absorbed by human skin. The UK system looks for dark areas which match certain size/shape limits that qualify as likely human faces.
A similar product uses 1550nm light. Fiber telecommunications band. Still near IR. I figured it had to be something like that to keep the laser costs down.
http://www.vehicleoccupancy.com/ http://technology.newscientist.com/channel/tech/motoring-tech/dn12384-infrared-vision-promises-more-road-tolls.html
There's a theory, which may or may not be correct, but which is popularly credited with fixing New York City. It goes something like:
Vigorously enforcing minor but ubiquitous and highly visible crimes (turnstile jumping, graffiti, etc.) eventually causes a societal shift whereby more serious but less visible crimes are reduced. I think it was a 'tipping point' theory or somesuch.
Anyway, I've never seen anyone arrested for not paying on a train. I've seen people offered a chance to buy a ticket. When they refused, they were thrown off at the next stop. Maybe a repeat offender might get the cops called, I don't know.