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Comment Re:Range is the issue (Score 2, Informative) 258

Most of the power is going to hauling a battery around.

That's a bit of an exaggeration/misinterpretation. Yes, the battery can be heavy; on a car with a reasonably long range like the Tesla, about a quarter of the weight (1,000-1,300 pounds) is the battery. On the other hand, some of that weight gain is offset by removing things that aren't needed - like the gas tank, fuel pump and hoses, gasoline itself (about 120 pounds for a full 20-gallon tank), as well as other components that aren't needed on an EV. As another example, a V8 engine weighs around 600 pounds; the Tesla Model S motor apparently weighs about 150 pounds - or 300 pounds if you include the reduction gear and inverter.

Anyway, the reason why range is difficult is that the energy density of gasoline is far higher than that of a battery. An 85 kWh battery, at ~1,300 pounds, has an energy density of 0.24 MJ per pound. Gasoline, on the other hand, contains about 19.2 MJ per pound. Even at the abysmal efficiency of an internal combustion engine (on average, about 20%), they still need 16 times less weight in fuel than an EV does in batteries.

The car companies are solving for a complex set of variables - the volume of the car dedicated to batteries, the weight (and thus power-to-weight ratio), the cost, the range requirements of their target market, etc. Tesla is trying to make the EV people's primary car, by using a huge battery capable of brief ultra-high-power recharging; most other companies have chosen to simplify, by marketing the EV as a family's second car - good for going to work, school, and errands (and 99% of most peoples' driving); but they still have a second car for road trips.

Comment Re:Safe (Score 1) 245

Yeah, this seems true to me too. Not too long ago, I bought a house, which involved faxing a wire request to my bank (in a different state). To prove my identity, they called the number I put on the form, and asked me a series of 10 security questions; I didn't have to give a driver's license or other documentation of my identity.

Honestly, I was a little surprised by how much the bank knew about me.

Similarly, when I needed my birth certificate to get a wedding license, they would have accepted a number of other documents (which are easier to replace) in lieu of a driver's license - like a paycheck and a utility bill.

Comment Re:Security through obscurity (Score 1) 481

I would disagree conditionally; security through obscurity is bad if it is your only form of security, and it's bad against a determined, well-funded attacker, but it can still provide some amount of security. Requiring an attacker to acquire an 8-inch-floppy disk (and drive) might serve to deter $SCRIPT_KIDDIE from doing anything to your system, because frankly, it's a pain. It certainly won't do much to deter $FOREIGN_SPY; it'll be a nuisance and probably add time to their planning of an attack (which is still beneficial), but you obviously need other security measures that can prevent their access.

You might think of it like many of the forms of cryptography used online today - the whole point is to create a math problem that would be very difficult for a third party to solve backwards, where "very difficult" is defined in terms of the computation power a potential attacker might have and a period of time after which the encrypted information would no longer have value. This means that encrypted data isn't vulnerable to anybody living today; but some day, it will be. If your goal were to encrypt data for all time (or against somebody with unlimited resources), you would need a very different mechanism to "obscure" your data than today's typical encryption. Security through obscurity is obviously weaker, but it can help to prevent casual attacks. (Then again, so could all the other stuff you have to do to prevent the more determined attackers - so adding obscurity is not helpful, but having it naturally does carry some small value.)

Comment Re:Fucking Cyclists are ruining the future. (Score 1) 174

Somebody else already pointed out the link, but you should NEVER put yourself in the situation where you are stopped to let a bicycle pass on the right. Even if I'm 100% absolutely positively certain that a driver has seen me and is waiting for me, I will never pass a car on the right in a situation like that unless there is literally no other option (ie I can't slow down and move behind them or to their left). You should have been paying closer attention, and either known that you could safely turn in front of the bicycle without cutting them off, or slowed down sooner and merged into their lane behind them. The latter is by far the preferable option, since most people tend to overestimate how much time they have to pass a cyclist and make their turn safely - especially if they find their right turn blocked by a pedestrian or another car.

(There are some situations where I will pass a car on the right, like when a long line of traffic is stopped at a traffic light, however once traffic starts moving, I will slow down so that I am in between two cars - so if either of them turns right, I won't be in danger of getting hit.)

This is actually something that the Google car did poorly in the video; when they demonstrate yielding to a bicycle passing on the right, the car should have been on the right in the bike lane, not to the left of the dotted white line. I'm hoping that they did this just to illustrate "hey look, we can see bikes coming from behind the car!", and that the car would normally be in the bike lane/shoulder in order to turn right.

One other thing - often, bicycles need to take the lane even when there is a bike lane. Perhaps the surface in the bike lane is too rough, or there is debris, or a poorly-designed storm sewer grate, or any of a thousand other possibilities. Without knowing the particulars, I can't guess whether one of those is what's happening, or if you just happen to commute along the same route as the world's largest asshole.

That said, yes, there are many crappy bikers out there. I'd like to think that if we started designing our transportation infrastructure more for bicycles (rather than including them as an afterthought), that would go away; more bike paths with fewer grade-level road crossings would go a long way. Also, making some roads (eg residential) nearly dedicated to bicycles can help - for example, put some planter boxes in a few places across the road, so only bicycles can pass through. Car traffic is reduced to only the residents, bicycles get a quiet place to ride, and cars don't have to jockey for position with them on the main thoroughfares. That only works if the bike route is sufficiently straight, goes somewhere interesting, and doesn't have many stop lights and stop signs - otherwise some bikes will prefer riding with more cars in order to have to stop less often.

Enforcement, or even just warnings, would also help. Doubly so if the laws were also adjusted to make sense for cycling; for example, the "Idaho stop", where a cyclist is allowed to treat the stop sign as a yield if there is no traffic approaching. But I'll admit I was amused when I was stopped at a red light, and a cyclist (obviously an inexperienced, low-income, casual biker) biked through, and a cop stopped in the middle of the intersection and yelled at him. ("That other cyclist stopped for the red light. You need to stop too. I don't want to have to fill out the paperwork when you become a road pizza.") The cyclist seemed confused at why he was getting yelled at (or was perhaps just putting on the "no hablo inglés" routine), so I don't know that it made things any better, though.

  Well, one rant begets another, I suppose... ;-)

Comment Re:base it around my OS (Score 1) 386

To be fair, it's linked from the IRS's website, so you shouldn't need to know the URL or have it advertised to you. But yeah, it's a pretty lame name.

It's apparently required by the IRS's agreement with the Free File Alliance for there to be an unbranded fillable form-type option for people whose income is above the 70% threshold that is set for other free file options.

It's also not the first industry-coalition-(somewhat-unwillingly)-supported website with a stupid name - how about annualcreditreport.com for another?

Comment Re:base it around my OS (Score 1) 386

I've been using freefilefillableforms.com for the past few years for federal, and it works fairly well. Nothing fancy like remembering data from previous years, though; the fanciest thing it does is compute some of the math for you.

My state does offer a couple different e-filing options, one of which is basically a pre-populated form that's ridiculously easy. Sadly, my taxes became about an order of magnitude more difficult this year, and so I didn't qualify for any of my state's online filing options, so I downloaded the PDF forms, filled them out, and mailed it in.

Comment Re:Cue the IRS kicking my door down in 3...2...1.. (Score 1) 386

Actually, the direct deposit will go through regardless of whether you screwed up or not - they'll just come knocking in about a year and a half if they find any mistakes, and ask for you to pay the difference, plus interest.

I had that happen twice - once when I legitimately made a simple mistake (they just told me how much to pay), and one other year; first, they questioned my earnings (my employer overpaid me, took back the difference, and then reported my original earnings on my W-2, and did not submit the corrected W-2 to the IRS); then they questioned one of my credits, for which I was allowed a special rate for living in a federally-declared disaster area. After I submitted proof for each item (and waited a month or two for a reply each time), they accepted my return as originally written.

So in general, it's usually not too painful a process even if you make a mistake. But I'm sure somebody will be happy to share their story below where it WAS a painful process... :-)

Comment Re:But Terrizm! (Score 4, Informative) 233

If it's an electrical fire (or if the pilots think it might be), they would turn off all the electrical systems; so ACARS, transponder, and radio are gone. Meanwhile, they're trying to extinguish the fire - it's still under control, they're just unable to communicate for fear that the electrical systems are causing the fire. And before they can either restore partial electrical systems or land, they become incapacitated by smoke.

Screaming for help is not a top priority. The priority is Aviate, Navigate, Communicate; first, you fly the plane, because that gives you time to do everything else. Then, you figure out where you're going; if you fail at this, you might end up somewhere unexpected, but at least you're alive. Finally, you communicate; if you're alive, it would probably be useful to tell somebody where you are and what's going on. Telling ATC that your plane is on fire and you're about to die of smoke inhalation is useless - FIRST you get the smoke and fire under control, at least long enough for you to navigate to an airport or piece of flat ground. Once that is manageable, THEN you communicate your distress. Even if they had communicated their distress early on, there's nothing that could have been done; there's no way for firefighters to board the plane and extinguish the fire while in midair, obviously.

If you listen to the "Miracle on the Hudson" ATC recording, the pilot is very brief and succinct; he communicates that he lost both engines and is returning, then that he is unable to return, then asks what the airport is on his right side, and then that he can't make it to that airport either and is heading for the Hudson River. There's lots of dead air when ATC asks him a question and he doesn't have time to respond.

I think the fire scenario is a pretty reasonable explanation, but it's by no means the only possibility.

Comment Re:no groping please? (Score 1) 141

This is all good advice. To that, I would add this: Pay attention to what causes you to get slowed down as you're going through. I've carried a number of odd items that have caused the TSA to flag me for a bag check - cheese, a game that contains hundreds of playing cards, a bowling ball, etc. When I'm carrying one of these items, I remove it from my bag and place it separately in a bin; if the X-ray operator can see it on its own, they usually won't call a bag check. Even if they do ask for a bag check, it only applies to that item by itself, which might get re-run or swabbed for explosive residue or something - meanwhile, your other bags make it through and you can start putting your shoes on and packing up your liquids while $agent does a brief check of $item (without having to search your bag for it).

As an example, take some cheese. (I was visiting home in Wisconsin, and needed my fix of good, inexpensive cheese, dammit!) It looks a bit like a liquid or an explosive. I can leave it packed in my carry-on bag, and sometimes they'd ignore it, but more often than not they won't. They call a bag check, so I have to wait for an agent to come over, then they have to wait for me to grab the rest of my items to meet them at the table. They dig into my bag looking for what the X-ray operator found (although they won't normally tell you what). Once they find it, they'll look over it a bit to make sure it's safe, then send both the bag and the item back through the X-ray, and then send me on my way if both look OK the second time through. On the other hand, if I take 10 seconds to pull it out of my bag BEFORE the X-ray, (and especially if I mention to the operator or agent next to the operator that I'm putting cheese through) then they don't need to do any extra inspection, although they may glance at the item on its way in or out of the X-ray tunnel.

Of course, all this is neglecting the best way to make it through: don't bring anything with you. Go to the airport barefoot, with no coat, belt, watch, or anything else. Check all your bags - hopefully you're flying Southwest so you don't have to pay for checked bags. The less you have, the less they are able to inspect. (Obviously, it's probably pretty difficult to do it to this extreme - but if you check a bag with your coat and liquids and belt, and only carry a tablet onboard with you, it's more likely to go quickly.)

Comment Re:well i'm reassured! (Score 2) 393

There are *vast* stretches of highway that are just as the GP described them - completely and without any barriers other than the median. Apparently you have driven on a select few roads in this country. I've driven many very long distance trips, and about the only region I have yet to drive through is the PacNorthwest.

Yes, of course there are many locations without barriers. In my area, there is insufficient space to have a grass median, and so every highway has a barrier between directions. It's a calculated equation of cost of land versus cost of a barrier, along with accident rates and traffic density. Of course, these aren't always updated, since the interstate system was designed so long ago and receives only few updates due to funds that are typically limited. I'm sure many places would warrant barriers now that did not when originally designed.

Thanks, Captain Obvious. I think the GP already stated "while driving the posted speed limit or less". I've hydroplaned at speeds of 15 mph in extremely heavy flow on I-35 near Dallas. Do you think either I or the GP continued to drive at that speed?

The point is, neither of you should have been driving that speed in the first place.

For normal traffic, there's no need to travel at 80 mph. In fact, it reduces gas mileage usually to go significantly above 55 or so, because air resistance increases much more rapidly and you have to fight that at high speeds.

Cite your sources for this often repeated tripe. My own MPG continues to rise until it peaks when my speed exceeds 110 mph. Most any car that I've owned (and none of them were your big honking pointless SUVs or any other sort of passenger truck) continued to increase in performance up to at least 80 mph. Even in the case of a Toyota Prius, the efficiency won't peak until approximately 75 mph. This statistic that you quote is a relic of the 1970's oil embargo years and the types of cars typically driven at that time. I somehow doubt it even applies to diesel big rigs these days either.

I would suggest a high school physics class. Aerodynamic drag at high speeds is proportional to the square of your velocity; so going from 55 to 110 mph doesn't double your drag, it quadruples it.

Also, I drive a Prius. There is a direct correlation between low speed and high mpg. Somebody even made this handy dandy graph of mpg at a variety of constant speeds in his Prius. The faster you go, the worse your fuel economy, full stop.

It is true that the optimal speed for mpg varies by vehicle; a lot of things go into the calculation, but you typically want to be at the lowest efficient speed in your highest gear; the efficient speed may be higher if your engine is particularly inefficient at low speeds. A good example of this was Top Gear's "race" of a Prius versus a BMW, with the Prius at top speed (~110 mph) getting 17 mpg, compared to the BMW which was getting 19 mpg (because it is optimized to run at much higher speeds).

So it may be possible that your car does very well at high speeds, because they optimized it for high speeds (did you buy some type of sports car?). But most passenger vehicles are optimized for the speeds that people normally drive - or rather, they're optimized for the EPA test cycle, which in turn is meant to be representative of what people normally drive.

Comment Re:Except for the fact that... (Score 1) 114

Yeah, this. The real "acoustic equivalent of one-way glass" would be to play some loud noise near the people who shouldn't be able to hear you - they have to yell really loudly to hear each other, which everybody else (including you) can hear over the noise. But they can't distinguish sounds you make from the noise because the noise is much closer and louder than you.

Comment Re:Questionable Numbers? (Score 1) 397

Not likely. I don't know a single EE that has gone for flipping burgers when unemployed (especially when unemployment in your field is still below 5%), although I'm sure that a few do. There are certainly lots of possibilities here; retirement, moving to management or another field, moving to a different country, measurement inaccuracies, etc. The point is, they don't say. They use the "10.4% of jobs were lost" to prop up the 1.4% unemployment increase as significant, but it's really not clear that it is.

Comment Re:Questionable Numbers? (Score 4, Informative) 397

Yeah, there's more too: Last year, there were 335k employed EEs with 3.4% unemployment, so about 347k EEs total. This year, there are 300k employed EEs with 4.8% unemployment, so about 315k EEs total. So by their numbers, sure, jobs declined by 10%, but the people looking for said work declined by 9% as well.

It's also worth noting that in their linked article from the year before, job numbers were up 25k; so the net from 2011 is a loss of 10k. Also, this variability makes me wonder if their method of counting is subject to a lot of noise, and we should be looking more at long-term average trends rather than year-to-year variability.

Comment Re:Shocking (Score 1) 409

Wages are NEVER on individual merit, unless your HR department is incompetent (given the generally-accepted definition of competency). The company's goal with setting wages is to pay each employee the minimum amount that will keep them happy. A star performer from the midwest or India (of any race) or anywhere else with a low cost of living probably has lower salary expectations than a mediocre performer from, say, California. The HR department is perfectly justified in coming up with a number to offer that they think will meet the individual's expectations - it's up to the individual to do their own research and decide if it is a fair wage or not. If it is fair to them, great. If it's not, then it's up to them to say "hey, I know other people in this position get paid $60k; I want that much too, plus I want relocation assistance and a bonus for uprooting myself and moving to a new country." This is called negotiation.

This is why almost nobody will publicly list all their employees' salaries; it's very demoralizing to find out that the schmuck next to you who stinks at his job did a better job at negotiating and is being paid 10% more than you are, despite your superior performance.

There are some exceptions to this rule; the idea is that the tradeoff of paying their employees more (to match both their expectations and their performance) might buy additional loyalty or satisfaction. I have no idea if this has been proven, but I doubt it. It probably just makes some ethically-minded executive feel better about the whole process. Meanwhile, the vast majority of executives know that ethics has no place in an efficient workplace.

(My university, which is a public state university, also published its employee salaries, as part of a state law requiring every agency to publish employee salaries for all state jobs. This was very helpful to the other universities so they could find the best and brightest, and offer a 10% raise to move.)

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