You have said in a really long-winded way that there's this built-in preservation of species instinct that you've got no control over. I understand. There's no need to rationalize and compare it to a sport or doing stunts, that's just silly, it's a different thing. Some people can get on top of it and overcome their instincts, some can't. No biggie. I just hate the rationalization and comparisons to breaking records... To be able to see how what you said is a rationalization, replace bearing children with your next big thing on the to-do list, then write it down, sleep over it for a week, then read it and see for yourself whether you get a chuckle out of it.
I don't buy the "sending your money out of your community to god knows who" argument. Somehow people who live in your physical proximity are more worthy of your money? That's silly.
It's NOT ridiculous to expect them to disappear completely. It IS ridiculous to expect them NOT to... because on the timeline we all live on, EVERYTHING will cease to exist at some point. Believing in the contrary is insane.
About my only complaint about electronic books is that browsing a paper version is still by my estimates an order of magnitude faster than an electronic version. You'd think they'd have solved that problem by now, but it seems that the solution -- whatever it may be -- is nowhere near. Try going into a library and browsing through a bunch of random books sitting on shelves. Then try the same feat using any available e-reader solutions. It's disappointing to say the least. And it's not a made-up, useless scenario. I enjoy going to my school's newly renovated library and just "surfing the stacks" for an hour once a month.
I don't think that's generally the case. At least if we talk about disciplines of science and engineering that have at least century-old history. The basics don't change all that much. In undergrad education in almost any subject, you could be using plenty of textbooks that are 50 years old, or more. For calculus you could use out-of-copyright stuff published in the late 1800s. Same for classical mechanics and mechanics of materials with exclusion of fracture IIRC. For chemistry, the basics are well covered by 1950s. Electronics -- here the basics are done by 1950s, too, although to learn about modern semiconductors you'd need something circa late 1970s. Physics -- again, 1950s are up-to-date enough, at least for a few semesters. Biology -- I'd be plenty happy if people who take only one semester of it were up to what was known in late 1950s. Mathematics -- unless you're into a modern applied branch of it, it's "done" by end of 19th century. General physics is IMHO current enough for undergrad courses as taught in Feynman's lectures, and those were done in late 1960s.
Of course there are outliers there. Astronomy has plenty of exciting stuff being found out every year, and I think it'd be foolish not to teach it pretty much up to 5 years ago, mentioning some newer discoveries as well. Software engineering is also a discipline where you better stayed current.
In almost every discipline you need to be current with available tools, even if the knowledge is a century old. I'd say that basic programming skills are applicable everywhere, and it'd be unhelpful if all you knew was, say, COBOL circa 1970. In any experimental discipline you should know sone scripting environment, a version control system, and how to tie it all together so that you can regenerate submittable output in minutes before deadline;) Basic software engineering practices don't hurt either, even if you're not going to be a software developer by trade.
Octave, maxima, svn, gnuplot, latex and gnu make have saved me untold grief over the years. Nothing like having an anacron entry that runs "svn co myproject; make submit" a couple minutes before the deadline (depending on how long the job takes, of course). For projects where there was more pressure, I preferred aegis over svn, as I'd at least be sure that whatever I check in builds and passes tests -- that can help a whole bunch when you've been up for 36 straight hours:)
It isn't a question of personal satisfaction... there's other forces at play there. Instinct, biological urges, hormones going haywire within peoples' systems
Look, if all that was driving me was instinct and biological urges, I'd probably have more kids with more women than I could reasonably remember. I think that being able to overcome instinct and urges is what makes us human. To think otherwise would imply that you should be OK to have teenagers fucking at every corner. If you're OK with that, then sorry, I'm barking up the wrong tree. Otherwise, what you pass for an argument doesn't fly by me so far, sorry.
Mom is passing one immunoglobulin (IgG) to the baby through placenta, sure, but isn't that a far cry from saying "someone with AIDS"? The baby's immune system is not suppressed, it will develop on its own pace and otherwise normally, just that whatever benefits IgG would have will be delayed by the 8 months or so. I'm sure the baby could be injected in-utero with IgG isolate from someone else -- perhaps the grandma could be a donor?
Breast milk contains all 5 immunoglobulins and will restore the baby's immune function very quickly. Sure the baby shouldn't nurse from an immunosuppressed mom, it will need breastmilk from other moms, or a wet nurse.
Heck, if the baby was to be formula fed only, that would still work as long as one would show a bit of initiative. Clean and abrade some skin on your forearm. Get some plasma dripping, add to the formula. Repeat every feeding. Voila, low-tech immunotranmismission. Of course maintaining a healthy wet skin abrasion for any amount of time requires some care, but it can be pulled off.
Did you just make up the 40 year "restoration period" figure in an attempt at FUD? Because that's just pure fiction.
These days, you don't even need an FPGA. Take any fast multicore chip like Parallax Propeller or fast multithreaded chip like XMOS XC-1 and you can emulate pretty much any retro 4 or 8 bit CPU at native or faster speed. With video output. All pretty much single chip -- all you need is a clock crystal and some voltage regulators. The propeller has 8 completely independent cores called cogs, each with 4 kbytes of dedicated RAM, and 32 kbytes of shared RAM in so-called hub. XC-1 has hardware multithreading with zero-overhead thread switching: it can run 8 threads in parallel, and thread switch is done after each single instruction, and those usually each take 1 cycle so you have true 400/500 MIPS performance, with 32 bit transfers.
There is a single cog Z80 implementation for Propeller, called ZiCOG, and it runs at about the speed of a Z80. Not cycle accurate, though. On XMOS, you can trivially run an order of magnitude faster, or more, and be cycle accurate at native speed. Both Propeller and XC-1 enable you to have a single-chip emulation of pretty much any 8 bit computer -- that is the CPU and everything else, with sound and video output. It's somewhat less work on XC-1 to keep it cycle accurate.
Methinks (if there's a particle physicist here, may she/he chime in) that it'd be a brand new thing if either process was observed, just that apparently momentum preserving neutrino emission is way more exotic than changing of the flavor. The latter requires a "detail" in the Standard Model to be wrong (neutrinos can't be massless as assumed until now), the former is some truly brand new physics. Perhaps even the latter would be Nobel material. Seems like they adjusted the prize to the curve recently, wink wink;)
I thought, though, that neutrinos changing flavors is pretty much a fact of life now, with MSW theory serving as a model.
I think it'd be Nobel prize material if one found neutrino-stimulated neutrino emission, as that is what you're alleging. I'm not saying it's impossible, just that IIRC my undergrad physics at all, it'd be a big discovery.
Wait a minute. The CMOS (not CCD IIRC) image sensor in the iPhone samples very, very slowly. At 30Hz, tops. The signal, to avoid problems with interference from flashing incandescents, etc, must be much faster than that. Think kilohertz. Probably the transmitter in the venue use standard 30-something kHz carrier used by remotes. You cannot sense this with a general purpose CMOS image sensor. You need a dedicated photodiode. Now of course they may go crazy and integrate a beam splitter in front of the image sensor to grab light for the diode, so that if you blind the photodiode, the image sensor is blinded too. This may add too much cost, though, so I'd think they'd slap the photodiode right next to the camera, but not in its optical path.
One thing I worry about is what sort of a transmitter optical power you need to make it reliably work. You don't want to scorch the retinas of someone who uses binoculars, for example. For that matter, there are binoculars with photo and video recording built in, even ones that look like old fashioned theater binocs;)
I agree. There were a couple semiconductor manufacturers, whose support ticket trackers had the same bug. I ended up helping out other people who had trouble with support drones. All it took was changing the ticket number in the URL. It's as trivial of a bug as it gets, yet I don't think it'll ever die out.
They didn't say if it's per a real or virtual server methinks, and I don't know if the assumption that they pay whatever anyone else would be paying holds water either. I'm sure they can get a lot more "server" for $1.5k than me or you would.
What a strawman. At this point you're either trolling or you seriously don't get my point.
In another post I've clearly stated that trucks have fairly poor braking performance and it's got nothing to do with their weight, just poor technology. A big rig's braking performance is about as good as a poorly adjusted emergency brake in your car, braking on rear wheels. Again, nothing to do with weight.
I've also stated that you have to do controlled comparisons: mechanical actuator, same chassis, same wheels and same stretch of road, under same conditions. It's a coincidence only that, say, an F150 with maximum load will brake over a longer distance than a Ferrari. If you were to cut said F150s weight down to that of the Ferrari, it wouldn't brake in any shorter of a distance. Then if you'd upgrade its tires to those of a Ferrari, it'd brake exactly as the Ferrari would. Really. You claim "let's look at this scientifically" -- I've already pointed you to objective data from the horse's mouth, so to speak. Both underlying physics and test resuts. Just look at the chart in the presentation I linked to in the post you reply to. Weight between 2500 and 6000 lbs has no effect on braking distance. None. That's the science you ask for.
You cannot willy nilly compare a big rig with a Ferrari, unless you first ensure that the big rig's braking performance is limited by the same thing as that of the Ferrari: road friction. Production (as opposed to test bed) big rigs can only get limited by road friction when they have ABS, hydraulic brakes and when there's no trailer.
Big rigs do brake in a much longer distance when they're loaded, but that's a consequence of their extremely poor braking system design and dynamic instability. It's not due to some imaginary physical law making braking distance get longer with load. U.S. big rigs use antiquated air-driven drum brakes, but even in Europe they still use air-driven discs. An air-based system makes for very poor ABS response, and you need ABS to stay road-friction-limited. The only sane way to do braking on a truck is to have a self-contained hydraulic brake system with a spring preload on both tractor and trailer, and an electrical link between them. At a slightly higher cost, one can have a double redundant diversity hydraulic system and then you don't need the spring preload. By "self contained" I mean having its own reserve power source, its own hydraulic pump, its own inertial sensors for stability augmentation, etc. It will stop on a dime.
From what I recall, the truck dynamics test bed I saw was braking about as good as a passenger car (under 40m from 100km/h to zero), so I would in fact gladly cut it off, stomp on the brake, and watch it stay a good distance from my back with 18 tons of load on the trailer. It's a sad state of affairs that production trucks are nowhere near that.
You will certainly feel differently because the inertia of the car changes. Again, the feel is entirely unimportant. You have to measure things, and you have to know that you're friction limited, and that can only be done with a reasonably good ABS system. That's why folks who discount ABS are quite silly IMHO.
To give you a visual aid in understanding how braking distance is unaffected by curb weight, look at a graph in this presentation (unfortunately it's PPT). You need to discount the idiotic fit they applied to the data as it's really meaningless. Cars/trucks with curb weights between 2500 and 6000 lb all stop between 100 and 150 feet, seemingly randomly distributed. I presume it's from 60mph to 0. Curb weight is pretty much unrelated to braking distance, all you see in that data is experimental error and varying tire/pavement conditions.
The SUV's tires must suck compared to passenger cars, then, as -- again -- it's not the weight but the coefficient of friction that affects the braking, assuming that friction limit is reached on all of the tires. If you'd get that Tahoe and cut off enough stuff off to make it as heavy as, say, BMW X6, it wouldn't magically stop in 30' less. It'd stop in exactly the same distance.
I do hope, though, that all those stopping distances are calculated with ABS activated, and with a mechanical actuator pushing on the brake and very quickly applying maximum pressure, as verified by recording pressure in the brake circuits. There's no uncomplicated way to make such tests with human in the loop.
Alaska's government has obeyed the letter of the law by releasing the emails. Nowhere in the law does it say that they have to release them in an easy to distribute format.
While true, what you're saying is that they can be jerks simply because there's no law about that. This is what irks me real bad. What about simply being a good person to others and also not fucking away a ton of paper simply because "there's no law against it".
Besides that, it IS customary to release FOIA documents in hard copy form, so this isn't surprising.
Yeah, it's customary for those who do the releases to be jerks because it's legal for them to be so. I mean, how effed up has one to be to have to go through all the trouble on both ends. Do all government jobs turn people into uncaring jerks with excuses for every stupid thing?
Big rigs are different since they are not, as you claim, friction limited. At friction limits on all wheels they are generally dynamically unstable. So stopping with all wheels at the friction limit causes loss of control unless you have control augmentation hardware, just like in stealth fighter planes. None of the production rigs come with it, you only get it in passenger cars, mostly as an option. Big rig brake systems AFAIK are pretty much technological relicts, kept around to cut costs only. I've seen a big rig test bed experiment with disc brakes on each wheel (in both tractor and trailer), and the controller had anti-lock and stability augmentation enabled. It was a sight to behold. You could slam the brakes, activate ABS, and the thing was going exactly where you wanted it to. There was no way to jackknife it while braking, no matter how hard you tried, and the braking distances with 18 tons of load made a joke out of a normal truck. Of course it was experimental, but still the effects that you mention are solely due to implementation choices, there's nothing fundamental about it.
Your test, when done on a car, must be always done with triggering ABS, on all wheels. Otherwise it's not valid -- there's no way for you to tell how close you are to becoming friction limited otherwise. If your emergency brake affects rear wheels, you can stagger ABS activation by adding a preload on the rear brakes. Then when you press the brake pedal you'll first hear rear brakes pulsing, then fronts will join in as you add more braking force. You can adjust the preload to get a good indication for how close you are to getting front ABS coming on.
To a first approximation, friction (thus braking torque, when you're friction limited) is proportional to the normal load -- the weight of the vehicle. That's the basic physics. A heavier vehicle automatically provides you with more available friction force. The AASHTO braking distance equation only depends on initial end final speed, and on coefficient of friction. The coefficient of friction does depend somewhat on tires, of course, so you cannot have an ultimate comparison with different tire types and sizes, unfortunately. You're pretty much bound to testing with one vehicle, with one set of tires, and different loads.
Whatever effects you're seeing are second-order and thus should be small, and relate IIRC first to tire contact area. You could compensate for the latter by adjusting the tire pressure to obtain same axle-to-ground distance. If you are still seeing an effect, then your tire's design is "poor" in that the effective coefficient of friction of tire vs. pavement depends on load; that's -- again IIRC -- due to changes in the geometry of the rubber elements that contact the pavement while being sheared. They deform due to shear in such a way that the effective friction coefficient changes, usually decreasing. I've seen plenty of variation in that effect in different tires. The more the tire is worn, the less pronounced the effect. Whatever we're talking of here is minuscule stuff in single percents. Nothing that will double your braking distance.
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You have said in a really long-winded way that there's this built-in preservation of species instinct that you've got no control over. I understand. There's no need to rationalize and compare it to a sport or doing stunts, that's just silly, it's a different thing. Some people can get on top of it and overcome their instincts, some can't. No biggie. I just hate the rationalization and comparisons to breaking records... To be able to see how what you said is a rationalization, replace bearing children with your next big thing on the to-do list, then write it down, sleep over it for a week, then read it and see for yourself whether you get a chuckle out of it.
You mean rednecks will take over? Shit.
I don't buy the "sending your money out of your community to god knows who" argument. Somehow people who live in your physical proximity are more worthy of your money? That's silly.
It's NOT ridiculous to expect them to disappear completely.
It IS ridiculous to expect them NOT to... because on the
timeline we all live on, EVERYTHING will cease to exist
at some point. Believing in the contrary is insane.
Amen.
About my only complaint about electronic books is that browsing a paper version is still by my estimates an order of magnitude faster than an electronic version. You'd think they'd have solved that problem by now, but it seems that the solution -- whatever it may be -- is nowhere near. Try going into a library and browsing through a bunch of random books sitting on shelves. Then try the same feat using any available e-reader solutions. It's disappointing to say the least. And it's not a made-up, useless scenario. I enjoy going to my school's newly renovated library and just "surfing the stacks" for an hour once a month.
I don't think that's generally the case. At least if we talk about disciplines of science and engineering that have at least century-old history. The basics don't change all that much. In undergrad education in almost any subject, you could be using plenty of textbooks that are 50 years old, or more. For calculus you could use out-of-copyright stuff published in the late 1800s. Same for classical mechanics and mechanics of materials with exclusion of fracture IIRC. For chemistry, the basics are well covered by 1950s. Electronics -- here the basics are done by 1950s, too, although to learn about modern semiconductors you'd need something circa late 1970s. Physics -- again, 1950s are up-to-date enough, at least for a few semesters. Biology -- I'd be plenty happy if people who take only one semester of it were up to what was known in late 1950s. Mathematics -- unless you're into a modern applied branch of it, it's "done" by end of 19th century. General physics is IMHO current enough for undergrad courses as taught in Feynman's lectures, and those were done in late 1960s.
Of course there are outliers there. Astronomy has plenty of exciting stuff being found out every year, and I think it'd be foolish not to teach it pretty much up to 5 years ago, mentioning some newer discoveries as well. Software engineering is also a discipline where you better stayed current.
In almost every discipline you need to be current with available tools, even if the knowledge is a century old. I'd say that basic programming skills are applicable everywhere, and it'd be unhelpful if all you knew was, say, COBOL circa 1970. In any experimental discipline you should know sone scripting environment, a version control system, and how to tie it all together so that you can regenerate submittable output in minutes before deadline ;) Basic software engineering practices don't hurt either, even if you're not going to be a software developer by trade.
Octave, maxima, svn, gnuplot, latex and gnu make have saved me untold grief over the years. Nothing like having an anacron entry that runs "svn co myproject; make submit" a couple minutes before the deadline (depending on how long the job takes, of course). For projects where there was more pressure, I preferred aegis over svn, as I'd at least be sure that whatever I check in builds and passes tests -- that can help a whole bunch when you've been up for 36 straight hours :)
It isn't a question of personal satisfaction... there's other forces at play there. Instinct, biological urges, hormones going haywire within peoples' systems
Look, if all that was driving me was instinct and biological urges, I'd probably have more kids with more women than I could reasonably remember. I think that being able to overcome instinct and urges is what makes us human. To think otherwise would imply that you should be OK to have teenagers fucking at every corner. If you're OK with that, then sorry, I'm barking up the wrong tree. Otherwise, what you pass for an argument doesn't fly by me so far, sorry.
"oxytocin which stimulates the brain to form love and bonding connections" is that fiction, or do you have anything to support that?
Is a need for personal satisfaction something that cannot be overcome?
Mom is passing one immunoglobulin (IgG) to the baby through placenta, sure, but isn't that a far cry from saying "someone with AIDS"? The baby's immune system is not suppressed, it will develop on its own pace and otherwise normally, just that whatever benefits IgG would have will be delayed by the 8 months or so. I'm sure the baby could be injected in-utero with IgG isolate from someone else -- perhaps the grandma could be a donor?
Breast milk contains all 5 immunoglobulins and will restore the baby's immune function very quickly. Sure the baby shouldn't nurse from an immunosuppressed mom, it will need breastmilk from other moms, or a wet nurse.
Heck, if the baby was to be formula fed only, that would still work as long as one would show a bit of initiative. Clean and abrade some skin on your forearm. Get some plasma dripping, add to the formula. Repeat every feeding. Voila, low-tech immunotranmismission. Of course maintaining a healthy wet skin abrasion for any amount of time requires some care, but it can be pulled off.
Did you just make up the 40 year "restoration period" figure in an attempt at FUD? Because that's just pure fiction.
These days, you don't even need an FPGA. Take any fast multicore chip like Parallax Propeller or fast multithreaded chip like XMOS XC-1 and you can emulate pretty much any retro 4 or 8 bit CPU at native or faster speed. With video output. All pretty much single chip -- all you need is a clock crystal and some voltage regulators. The propeller has 8 completely independent cores called cogs, each with 4 kbytes of dedicated RAM, and 32 kbytes of shared RAM in so-called hub. XC-1 has hardware multithreading with zero-overhead thread switching: it can run 8 threads in parallel, and thread switch is done after each single instruction, and those usually each take 1 cycle so you have true 400/500 MIPS performance, with 32 bit transfers.
There is a single cog Z80 implementation for Propeller, called ZiCOG, and it runs at about the speed of a Z80. Not cycle accurate, though. On XMOS, you can trivially run an order of magnitude faster, or more, and be cycle accurate at native speed. Both Propeller and XC-1 enable you to have a single-chip emulation of pretty much any 8 bit computer -- that is the CPU and everything else, with sound and video output. It's somewhat less work on XC-1 to keep it cycle accurate.
Methinks (if there's a particle physicist here, may she/he chime in) that it'd be a brand new thing if either process was observed, just that apparently momentum preserving neutrino emission is way more exotic than changing of the flavor. The latter requires a "detail" in the Standard Model to be wrong (neutrinos can't be massless as assumed until now), the former is some truly brand new physics. Perhaps even the latter would be Nobel material. Seems like they adjusted the prize to the curve recently, wink wink ;)
I thought, though, that neutrinos changing flavors is pretty much a fact of life now, with MSW theory serving as a model.
I think it'd be Nobel prize material if one found neutrino-stimulated neutrino emission, as that is what you're alleging. I'm not saying it's impossible, just that IIRC my undergrad physics at all, it'd be a big discovery.
Wait a minute. The CMOS (not CCD IIRC) image sensor in the iPhone samples very, very slowly. At 30Hz, tops. The signal, to avoid problems with interference from flashing incandescents, etc, must be much faster than that. Think kilohertz. Probably the transmitter in the venue use standard 30-something kHz carrier used by remotes. You cannot sense this with a general purpose CMOS image sensor. You need a dedicated photodiode. Now of course they may go crazy and integrate a beam splitter in front of the image sensor to grab light for the diode, so that if you blind the photodiode, the image sensor is blinded too. This may add too much cost, though, so I'd think they'd slap the photodiode right next to the camera, but not in its optical path.
One thing I worry about is what sort of a transmitter optical power you need to make it reliably work. You don't want to scorch the retinas of someone who uses binoculars, for example. For that matter, there are binoculars with photo and video recording built in, even ones that look like old fashioned theater binocs ;)
I agree. There were a couple semiconductor manufacturers, whose support ticket trackers had the same bug. I ended up helping out other people who had trouble with support drones. All it took was changing the ticket number in the URL. It's as trivial of a bug as it gets, yet I don't think it'll ever die out.
They didn't say if it's per a real or virtual server methinks, and I don't know if the assumption that they pay whatever anyone else would be paying holds water either. I'm sure they can get a lot more "server" for $1.5k than me or you would.
What a strawman. At this point you're either trolling or you seriously don't get my point.
In another post I've clearly stated that trucks have fairly poor braking performance and it's got nothing to do with their weight, just poor technology. A big rig's braking performance is about as good as a poorly adjusted emergency brake in your car, braking on rear wheels. Again, nothing to do with weight.
I've also stated that you have to do controlled comparisons: mechanical actuator, same chassis, same wheels and same stretch of road, under same conditions. It's a coincidence only that, say, an F150 with maximum load will brake over a longer distance than a Ferrari. If you were to cut said F150s weight down to that of the Ferrari, it wouldn't brake in any shorter of a distance. Then if you'd upgrade its tires to those of a Ferrari, it'd brake exactly as the Ferrari would. Really. You claim "let's look at this scientifically" -- I've already pointed you to objective data from the horse's mouth, so to speak. Both underlying physics and test resuts. Just look at the chart in the presentation I linked to in the post you reply to. Weight between 2500 and 6000 lbs has no effect on braking distance. None. That's the science you ask for.
You cannot willy nilly compare a big rig with a Ferrari, unless you first ensure that the big rig's braking performance is limited by the same thing as that of the Ferrari: road friction. Production (as opposed to test bed) big rigs can only get limited by road friction when they have ABS, hydraulic brakes and when there's no trailer.
Big rigs do brake in a much longer distance when they're loaded, but that's a consequence of their extremely poor braking system design and dynamic instability. It's not due to some imaginary physical law making braking distance get longer with load. U.S. big rigs use antiquated air-driven drum brakes, but even in Europe they still use air-driven discs. An air-based system makes for very poor ABS response, and you need ABS to stay road-friction-limited. The only sane way to do braking on a truck is to have a self-contained hydraulic brake system with a spring preload on both tractor and trailer, and an electrical link between them. At a slightly higher cost, one can have a double redundant diversity hydraulic system and then you don't need the spring preload. By "self contained" I mean having its own reserve power source, its own hydraulic pump, its own inertial sensors for stability augmentation, etc. It will stop on a dime.
From what I recall, the truck dynamics test bed I saw was braking about as good as a passenger car (under 40m from 100km/h to zero), so I would in fact gladly cut it off, stomp on the brake, and watch it stay a good distance from my back with 18 tons of load on the trailer. It's a sad state of affairs that production trucks are nowhere near that.
Your gut feel is entirely wrong. Sorry.
You will certainly feel differently because the inertia of the car changes. Again, the feel is entirely unimportant. You have to measure things, and you have to know that you're friction limited, and that can only be done with a reasonably good ABS system. That's why folks who discount ABS are quite silly IMHO.
To give you a visual aid in understanding how braking distance is unaffected by curb weight, look at a graph in this presentation (unfortunately it's PPT). You need to discount the idiotic fit they applied to the data as it's really meaningless. Cars/trucks with curb weights between 2500 and 6000 lb all stop between 100 and 150 feet, seemingly randomly distributed. I presume it's from 60mph to 0. Curb weight is pretty much unrelated to braking distance, all you see in that data is experimental error and varying tire/pavement conditions.
No shit, Sherlock. And we expected what else, exactly?
Good point.
The SUV's tires must suck compared to passenger cars, then, as -- again -- it's not the weight but the coefficient of friction that affects the braking, assuming that friction limit is reached on all of the tires. If you'd get that Tahoe and cut off enough stuff off to make it as heavy as, say, BMW X6, it wouldn't magically stop in 30' less. It'd stop in exactly the same distance.
I do hope, though, that all those stopping distances are calculated with ABS activated, and with a mechanical actuator pushing on the brake and very quickly applying maximum pressure, as verified by recording pressure in the brake circuits. There's no uncomplicated way to make such tests with human in the loop.
I'm not so sure. Ever seen a plasma cutter go through steel blades that are many inches thick? You can stand fairly close to it.
Alaska's government has obeyed the letter of the law by releasing the emails. Nowhere in the law does it say that they have to release them in an easy to distribute format.
While true, what you're saying is that they can be jerks simply because there's no law about that. This is what irks me real bad. What about simply being a good person to others and also not fucking away a ton of paper simply because "there's no law against it".
Besides that, it IS customary to release FOIA documents in hard copy form, so this isn't surprising.
Yeah, it's customary for those who do the releases to be jerks because it's legal for them to be so. I mean, how effed up has one to be to have to go through all the trouble on both ends. Do all government jobs turn people into uncaring jerks with excuses for every stupid thing?
Big rigs are different since they are not, as you claim, friction limited. At friction limits on all wheels they are generally dynamically unstable. So stopping with all wheels at the friction limit causes loss of control unless you have control augmentation hardware, just like in stealth fighter planes. None of the production rigs come with it, you only get it in passenger cars, mostly as an option. Big rig brake systems AFAIK are pretty much technological relicts, kept around to cut costs only. I've seen a big rig test bed experiment with disc brakes on each wheel (in both tractor and trailer), and the controller had anti-lock and stability augmentation enabled. It was a sight to behold. You could slam the brakes, activate ABS, and the thing was going exactly where you wanted it to. There was no way to jackknife it while braking, no matter how hard you tried, and the braking distances with 18 tons of load made a joke out of a normal truck. Of course it was experimental, but still the effects that you mention are solely due to implementation choices, there's nothing fundamental about it.
Your test, when done on a car, must be always done with triggering ABS, on all wheels. Otherwise it's not valid -- there's no way for you to tell how close you are to becoming friction limited otherwise. If your emergency brake affects rear wheels, you can stagger ABS activation by adding a preload on the rear brakes. Then when you press the brake pedal you'll first hear rear brakes pulsing, then fronts will join in as you add more braking force. You can adjust the preload to get a good indication for how close you are to getting front ABS coming on.
To a first approximation, friction (thus braking torque, when you're friction limited) is proportional to the normal load -- the weight of the vehicle. That's the basic physics. A heavier vehicle automatically provides you with more available friction force. The AASHTO braking distance equation only depends on initial end final speed, and on coefficient of friction. The coefficient of friction does depend somewhat on tires, of course, so you cannot have an ultimate comparison with different tire types and sizes, unfortunately. You're pretty much bound to testing with one vehicle, with one set of tires, and different loads.
Whatever effects you're seeing are second-order and thus should be small, and relate IIRC first to tire contact area. You could compensate for the latter by adjusting the tire pressure to obtain same axle-to-ground distance. If you are still seeing an effect, then your tire's design is "poor" in that the effective coefficient of friction of tire vs. pavement depends on load; that's -- again IIRC -- due to changes in the geometry of the rubber elements that contact the pavement while being sheared. They deform due to shear in such a way that the effective friction coefficient changes, usually decreasing. I've seen plenty of variation in that effect in different tires. The more the tire is worn, the less pronounced the effect. Whatever we're talking of here is minuscule stuff in single percents. Nothing that will double your braking distance.
How thick must one be not to understand something that I have repeatedly stated. Sigh.