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Comment Re: Too extreme (Score 1) 306

I was also talking about working conditions. A lead-acid battery can work decently well in conditions right down to -60F. I've started a car that was stored in conditions that will leave the lithium-ion batteries as useful as a brick. (A few days ago, my wife's car started at -25F (~-30C) without any heat to the battery or engine.) About 15 years ago, I was working on a power cart intended to provide continuous cathodic protection to a pipeline in arctic conditions. We were able to design the system so that (with a small margin) the batteries could be stored outdoors without additional heat down to temperatures of -70F. Again, these are working conditions at which lithium ion batteries can't be made to work without difficult and potentially costly adaptations. You may think these fringe cases, but for me these are quite common conditions.

Comment Re: Too extreme (Score 1) 306

. . .and yet the electrolyte in a fully charged lead acid battery doesn't freeze until about -90F (~-65C). The battery continues to provide lesser current down to the freezing point. I can personally attest that there's enough juice in a good battery to start a car at -55F without either having been warmed or charged. (I only started a car that cold once.) My wife forgot to plug her car into the timer last night, and I started it this morning at -25F.

Lithium-ion batteries stop functioning at -40C, and are pretty useless at temperatures below -20C. Despite the recommendations you cite, lead-acid has a safe working range that covers a pretty darn wide temperature range.

p.s. I went looking and found a pretty chart for you: https://i2.wp.com/mathscinotes.... The chart shows a slightly lower freezing temperature than I recollect.

Comment Re:Not news until his salary is $0 (Score 1) 336

Go to the macsales home page. Don't click through to the detail page that the image of the product links to, though. Go ahead, I'll wait.
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On the front page, and only on the front page is a picture that shows a little bridge joining one of the Mac's ports with the DEC. Every other picture that I've seen omits that little detail.

Comment Re: Metric / Imperial (Score 2) 167

Name them.

een
twee
drie
vier
vijf
zes
zeven
acht
negen
tien
elf

Happy now?

The Amsterdam foot (voet) consisted of 11 Amsterdam inches (duim). It was more complex than just 11 inches to the foot, though: Dutch feet varied from 10 to 13 inches depending on local laws. The variability in units of measure varied this way throughout Europe.

Comment Re:Why avoid again? (Score 1) 84

My wife and I both have an iphone 6s and use different carriers. I'm on a regional GSM carrier (GCI) while she uses Verizon (CDMA). We occasionally travel to Chena Hot Springs, where there is a single CDMA tower owned by GCI. (GCI recently bought the Alaska Communications System cell network, which is CDMA.) My wife has a signal, while I have nilch. I won't call this confirmation that a t-mobile phone won't roam onto a Verizon CDMA network, but it's suggestive. Isn't the spectrum also different?

Comment Re:Collusion is illegal (Score 1) 585

Ha! I'm still running a 9 year old Q9400 as my desktop, and a 14 year old AMD CPU is taking care of media. Neither of them are fast, but I also prefer Linux. (Windows is there for a few games, Rosetta Stone and to back up my phone.)

I must admit, though, that I'm thinking of upgrading. I'm a bit disappointed, though, by the news as I was thinking of a nice, shiny Zen processor in January and I'd prefer to stick with Window 7 for now. I find it easiest to keep my Windows version in sync with what's prevalent at work. Ah well; maybe I'll just dump Windows and figure out something for the little bit I use it for.

Submission + - Jeff Bezos, of Amazon.com and Blue Origin, wants to move heavy industry to space (blastingnews.com)

MarkWhittington writes: SpaceX’s Elon Musk wants to settle Mars. To be sure, Musk’s rival, Jeff Bezos, CEO of both Blue Origin and Amazon.com, thinks that is pretty cool too. But he has just as an ambitious vision for the future. He would like to move all heavy industry into space, according to Recode. The Earth would be rezoned for residential and light commercial use.

Comment Re:Moronic to say the least (Score 1) 602

. . .but I think the idea is to actually have less accidents. . .

And you're wrong to think so. Crashes are generally classified by type with a cost assigned to each: fatal, major injury, minor injury and property damage only (PDO). An uncontrolled intersection may have on average 0.25 fatal crashes per year, and through examination of similar intersections we might predict that adding controls will change that to 5 minor injury and PDO crashes per year. Because the monetary cost assigned to the fatal accident is so (justifiably) high, the controls should be added even though the total number of crashes increases.

Comment Re:More nation-wrecking idiocy (Score 4, Informative) 602

Here's a well-traveled street straddling Beverly Hills and Los Angeles. It has no longitudinal traffic markings, and particularly from 3:00PM to 7:00PM has heavy traffic. The accident rate is modest, particularly given its narrow width and placement parallel to and between two major arterials.

Here's a well-traveled street in Fairbanks, AK. From October until April there is regularly snow that can quite effectively cover lane markings for days or months at a time. For example: I noticed this morning, only because the packed snow and ice had finally worn away enough to make the markings faintly visible, that I was driving through a painted median. A week ago I noticed three cars side-by-side to make left turns into two receiving lanes because snow had obscured the lane markings; they worked it out when the light changed and nobody died.

Three years ago, as the traffic & safety engineer, I was designing the signs and markings for a rural two-lane road that hadn't been previously paved. One discussion was the necessity of the inclusion of longitudinal markings. In the end, we painted the center lines and excluded the edge lines.

In the US, the MUTCD establishes a base requirement for center line markings on roads "that have a traveled way of 20 feet or more in width and an ADT of 6,000 vehicles per day or greater" or on two-way roads "that have three or more lanes for moving motor vehicle traffic." On many roads, center lane lines are already optional and their exclusion isn't an inherent problem. I might argue differently about reactionary idiots, however.

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