The best way to do it is just look at the watermark and or security ribbon. That detects even washed and reprinted bills, though those are more the realm of, say, Russia than someone off the street. If you get a UV light, the security ribbon will fluoresce different colors depending on the bill. It's quicker than looking through the bill, but might not actually be as effective in the sun (I gather that the $100s are particularly troublesome to fluoresce/see).
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> Nobody wants to pay for claims arising from behavior riskier than their own.
Well of course! Because when bad things happen to other people it's because of their risky behavior, and when they happen to you it's "bad luck".
On a related note, I wonder how many more accidents happen because of "safe" behavior done mindlessly than "risky" behavior done safely...
> First off, almost nobody is missing steps in their cheap 3D printers. They simply do not move fast enough for that to happen.
> And if they are missing steps you have a bigger issue, usually lots of friction somewhere.
Well, keep in mind that not moving fast enough is a bit circular: One reason they don't move fast enough is to prevent them from skipping steps. Of course, on hobby machines rigidity is probably a bigger issue so it's not terribly helpful in that regard.
(I will say, though, that steps can be missed outside normal operation if the machine crashes. Feedback is nice for identifying that quickly!)
> Secondly, 200 steps per rotation is normal for motors. However, the drivers everyone is using do 16x microstepping,
> good for 3200 steps per revolution. Accurate steps per revolution. That's better then 4096 +- 2 steps.
No. Microstepping (and indeed stepping at all!) is a zero torque accuracy. In a motor, torque is only generated when the magnetic fields are unaligned, a situation known as "slip". If the fields are aligned (zero slip), there is no force and so no torque, but the rotor is exactly where you expect it. Maximum torque occurs at 90 degrees from the poles, and if that is exceeded you lose a step. The idea of the stepper is that the poles are so close that the maximal 90deg slip (+/- 1/4 step) is insignificant (usually only a degree or less) and therefore you can infer an amount of positioning based on that. All microstepping does is rotate the poles; you will still have the same uncertainty because the width of the poles is unaffected.
Granted, if the stepper in providing much more torque than is needed the slip will be pretty small. However, unless you have very low friction and zero other torque you can usually expect to always be a least a (16x) microstep or two off your expected rotation. Haven't you ever wondered why the advent of cheap microstepping drives hasn't killed small step steppers and encoders? You're still only as accurate as your physical step size.
In addition, steppers are generally used with minimal gearing. Other motors will usually have to be geared down pretty significantly which means that a motor mounted encoder will provide a "geared up" precision. Yes, backlash can be a problem but it's actually not a much as people like to think (for reasons beyond the scope of this discussion).
So to compare:
A) 200 step stepper, 16x microstepping, direct-drive : ~1000 counts per rev
B) Brushless DC motor with 4096 encoder and 10:1 gear box: ~20000 counts per rev.
> I'm also willing to argue that it's more expensive.
You better believe it! Brushless DC motors are less expensive than steppers, usually, but steppers are a one piece solution. All you need is a single chip driver and a shaft coupling are you're done. If you want to use a DC motor, you need all that and a gearbox (which could maybe be a low pitch ball screw in this application), an encoder, an encoder reader (a microcontroller is fine, but one per axis!). You also need better control software too.
In the end, though, you get what you pay for and that setup will beat the tar out of a stepper directly driving a timing belt. However, it's also far better than your average reprap mechanics, which will lack to rigidity to actually use it to its fullest. So now you have to build a better frame, etc, etc. And all of a sudden you've got a $20k industrial machine and not a $1k hobby one.
So, I agree that for the application there is nothing at all to see here. Cheap servos for a cheap machine are pointless and steppers are the right solution. After all, the difference between 1k and 100k counts per rev doesn't really matter if your extruded plastic is +/-0.1mm. However, for a better machine a closed loop servo is really the only way to go.
Yeah pretty much.
The trouble, of course, isn't that people are too stupid or too obstinate to understand, it's that the case being made it setting off BS alarms everywhere. Global warming is a hard sell when Al Gore is guzzling gas flying around the world to talk about how bad it is and how people need to cut back. Anyone is going to look at that and see "cutting back" as what the poor need to do to sustain the lifestyles of the rich, and 'carbon credits' as the excuse. People know that nuclear power doesn't emit CO2, but the fact that it isn't being pursued as a solution indicates that global warming isn't as scary as nuclear power. And rather than reuse-reuse-recycle programs, we get consume-more programs like cash for clunkers and cell phone kill switches.
The problem isn't with communication, it's about leadership. Show people that you're concerned, and maybe they'll start to believe you. Or don't and just fuck them over... it's a nice win-win for those in charge.
> I don't know why forcing everybody in the United States to buy managed healthcare plans would improve the situation at all.
It's not; it's more of a deal with the devil, if you will. Forcing people to buy insurance is mostly the corporate handout part of the bill, made in exchange for things like the insurance companies loosening pre-existing condition restrictions, etc. (Whether it's a good deal is certainly up for debate, but I don't think it was.)
As I mentioned above, hospitals must help people too poor to pay, and they loose a lot of money; by forcing people to buy insurance, they can get paid. And, of course, the insurance companies are paid too, because they ultimately change more than the cost (that's how insurance works). Because the poor get subsidies, it's mostly taxpayer money fueling that machine. Additionally, it forces young people to buy insurance which is a generally quite profitable area since problems in young people are generally much less frequent and expensive to treat.
At the end of the day, though, it doesn't really do anything to fix the anti-free-market effects that created the problems to begin with. It just cements the protection racket in place (particularly with the pervasive deductible plans): pay an insurance company or pay 3x the fair price when you see a doctor.
> This ALWAYS this you crybabies whine about right up until it is your ASS being left out front of the hospital. Then it is all about SAVE ME!
Prior to ACA hospitals were required to provide emergency medical care regardless of the person's ability to pay under the EMTALA. Granted it might not be great care, but the idea that someone would be left out of a hospital if they had a serious problem is just FUD. Theoretically people are still responsible for paying any care they receive, but in practice so often they are low income with a lot of debt already and the hospital will just write it off.
In fact, one of the reasons for ACA was because the EMTALA was a huge problem. It was estimated that about 55% of emergency care goes uncompensated. By forcing people to carry insurance, hospitals will be less on the hook for emergency care.
So to your point, with or without ACA you wouldn't be left out of a hospital, but now with ACA they can better make you pay.
The 16th amendment is extremely dangerous. It gives the federal government the constitution power to tax your income without limit or restriction. While a "free speech tax" per se might be ruled unconstitutional, when it comes to freedom regarding your money the rule is quite clear: pay your taxes or else.
So, you are "free" to not pay the insurance companies, of course, but the government is allowed to tax you as much as they want if you don't (well, if you do too, but for less at least). Maybe it might be worth it to you at some penalty level, but that can always change.
> People with religious delusions want everything to be about their cults, but reality doesn't work that way.
Way to flamebait. Good thing you're on the party line or you'd have gotten modded down.
The simple fact of the matter is, that everyone wants everything to be about their beliefs, "cult" or not. In a democratic society we work out (or are supposed to) something that works as a good enough compromise, but at the end of the day it's basically all arbitrary crap. I doubt you'll find a law on the books that derives itself from anything much like pure reason... They're really all there because people didn't like one thing or another, and wanted to make sure that wasn't allowed. "That's annoying" "That's mean" "That's weird" "That cost me money", etc. Really, "against my religion" is probably one of the rarer reasons for a law to be on the books. When it comes to gay marriage, I quite honestly think that more people are against it because "That's gross" rather than any religious reason; they just use religion as an easier point of debate.
Microwaves are pretty much totally on my point because:
A) They cost like $50 for a cheap model
B) Meals are cheaper than the cheapest restaurant
If 3D printers get to that point, they may become mainstream.
> More like the fact that CAD software packages cost many thousands of dollars, and no good free alternatives exist.
> Or that mechanical design is inherently challenging and is an expensive skill to develop.
I'd say that these are not "mainstream" issues but rather content creation issues (and creators are quite niche). While text documents are pretty easy to create for a normal printer, once you move past those content creation becomes much more challenging and niche. DVD burners are pretty mainstream, but home mainstream is movie production? Etc.
> Or that the printers themselves for commercial grade machines also cost many thousands of dollars.
That's the real issue. From a mainstream, consumer perspective, what's the value of a 3D printer? If you aren't a creator making sculptures or parts for other creations, what do you make? And what's the savings vs buying it or something quite similar?
There are enough people in this world that basically every generally useful product is cheaply mass produced and widely available. When it comes to consumers, 3D printers are a solution looking for a problem. Until they cost only a couple hundred bucks and can produce sporks for cheaper than you can buy them at Walmart, there just isn't enough utility for them to go mainstream.
I'm skeptical of those numbers anyway: There have been times where the total number of humans was less than 40k with some speculation that there were as few as 2k for a while. That discounts, say, early settles to regions that then became the native people. How large a group traveled through the Bering Strait to the Americas? With current knowledge, we could screen the initial people for genetic diseases and organize breeding programs to maintain diversity, so we could probably be successful with even less.
Anyways, the ability to freeze bits (sperm, eggs, embryos) already exists and the projected lifetime of sperm at least would easily cover the journey plus the formative years. Heck, it's probably a better solution than legions of people even from a purely genetic perspective as you could probably better control radiation damage.
So that means genetics aren't really going to be as important as:
*) Builders - You aren't going to grandma's. You'll need able-bodies people to build you colony. Robots can help, but it's still going to require a decent crew. Even if you don't maintain this size group throughout the journey, you'll need it when you arrive, meaning the ship needs to have facilities for them to grow up in.
*) Parents - You need to keep people alive to teach new people what being people is. Books and other media will help, but you need a decent assortment to give an understanding of 'society' and prevent one bad egg over the 300 years from spoiling the bunch.
*) Society - Kinda tied to the last point, but you can't just have 10 people playing poker for 300 years. You need some ability to socialize, have friends, create, consume, etc.
I'd side with the anthropologist on this one: 150ish, a small village worth. Genetics are basically a solved problem and pretty much a footnote on the laundry list of problems that colonizing would face. Heck we don't even know if Proxima Centauri has a planet!
> If I run a website, I'm not allowed to control or limit what comments and content other people put on it?
Of course you are, but only if you actually want to. If the government tells you to control it or else they'll drag you through audits/courts/etc until you do then that's a problem.
Granted, said government in this case is the Chinese, so I'm not surprised the case was thrown out but I can understand why it was brought.
Sure content providers may not always know what's going on, but they are most certainly not so out of touch as to think that ripping steams is a real concern. Well, maybe in so far as an end user tool to save the stream might be a threat, but realistically DVD and BR are easily rippable and better quality so I doubt the concern is that great.
Ridiculously high is right.... 11 nines uptime works out to be less than a millisecond per year. At that level if you're going to need to specify allowable ping times.
In reality, Google only offers 99.9% per month (99% for "reduced availability", I'm not sure what these prices are for) and the value of the guarantee is pathetic: they credit (not even refund) you a maximum of half your bill that month if availability is =95%. They could be down a full day and only knock 25% of you bill next month. That can barely be considered an SLA.
Also, given that consumer internet is 100% (to be generous!) you're basically guaranteed better uptime in the common case (accessing your data at home) storing it locally. If you're hosting via, say, ownCloud for use by your phone then, sure, Google Drive may have better uptime.
Anyways, given the premium over a hard drive as the parent pointed out, you just buy (and power) two and run as RAID0. You could even buy a spare or two which could be used as a backup until one of the primaries failed.
Regardless of whether or not 20TB is hording / excessive / inefficient, what it almost certainly is is replaceable. Let's face it, you aren't CERN, most of you data is probably media that you can reacquire with relative ease. It's not being stored because it's irreplaceable it's being stored because it's convenient. A RAID isn't too bad, but add in managing backups and where has that convenience gone? If it costs $10+/month to backup your ripped/downloaded movies, why not just sign up for Netflix?
Just make a list of all the replaceable data (e.g. videos you have the original disc for) you have and then buy an external hard disk / Blurays to back up the rest. If you lose your RAID, well, it'll be annoying to rebuild, but you built it once... (Besides, I doubt you could restore 20TB over residential internet less time!)