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Comment Re:this write-up is wrong (Score 1) 106

Perhaps I should be more specific in my criticism of lunars.

At the time, you could get good accuracy out of either clocks or lunar distances. However, it required either really really highly trained trained and disciplined crew (for lunars), or very very expensive clocks. If you're just using lunars, you have to be quick about it to get a good fix, and then you have to do a good job of your dead reckoning to track your position until you get another absolute fix. In any sort of poor conditions, your dead reckoning quality will go down, and your ability to take another absolute fix goes down. That is, you have to dead reckon for longer periods (potentially a few days). Further, over time your dead reckoning estimates will drift by as much as your clock is bad (since you must have some sort of clock to dead reckon even if you get your longitude from the moon).

With an expensive (frightfully so!) clock, you get a better initial absolute fix, depending on how expensive your clock was. However, you can get location fixes more often, with less visible sky, so you don't have to dead reckon for as long as often. You also find dead reckoning easier, since you have a good clock to base your estimates on.

The admiralty found the lunar distance method acceptable because they were already dependent on highly disciplined and trained crews for fighting, and for their existing navigation. The only real problem they ever had with clocks was the expense. Even so, for more important voyages (e.g. James Cook's exploration of the Pacific) and larger flotillas, they paid up. Once the prices dropped, clocks won out.

Comment Re:this write-up is wrong (Score 1) 106

Um... Maskelyne's method is the lunar distance method. Although he also used observations of the moons of Jupiter for measuring fixed locations on earth. Maskelyne was in charge of running the tests for several longitude methods, but the only two that were taken seriously for use at sea after the first trials (indeed, even during the first trials) were the lunar distance method and good clocks (specifically that made by Harrison).

Comment Re:this write-up is wrong (Score 4, Informative) 106

You do not need a clock to determine longitude. In fact, a sextant can be used, as long as you have the appropriate tables that map various celestial angles to the correct date and time. These tables were originally overseen by Nevil Maskelyne, one of Harrison's rivals to the longitude prize.

I was going to bring up myself that technically, you don't need a clock, because of the lunar distance method. However, that's only a "technically"; the lunar distance method was never really practical for use at sea.

The two methods are an early instance of the closed-tech vs open-tech argument we're so used to now.

To call it open vs closed is a little bit of an overstatement. Harrison disclosed how his clocks worked and their method of manufacture. He did have patents on some of the techniques, but for the speed technology moved at the time, the length of the patents were quite reasonable. (Also, IIRC the admiralty was allowed to licence it out to others for a fixed rate).

The big thing is that longitude is hard. To this day a mechanical clock which can keep time well enough for accurate navigation is an expensive and specialized thing. Irrespective of patents, such clocks were simply expensive to build. However, once you bought one, they were easy to use. The lunar distance method required little in the way of equipment (that is, it had low capital outlay). However, it required highly accurate relative measures of many astrological features in a short time. From the deck of a rolling ship. With finicky table lookups. At night. With a bunch of finicky calculations afterwards. And of course, if it was partly cloudy and you couldn't make all of your measurements, well, you'd better hope your sand watch (that is, hourglass) had good holdover. That is, even with the lunar distance method, you still had to have good timekeeping to figure out your in between positions.

The insurance companies (that is, Lloyd's and their subgroups) eventually forced mercantile adoption of Harrison's clocks. And of course, today we just use clocks. Atomic clocks moving in relativistic conditions, but still easier than the lunar distance method.

Comment Re:Stupid FUD (Score 1) 303

If a malicious user gain physical access to your network, a high-voltage attack is the least of your worries. Network sniffers and other tools can quickly own your entire network doing far more monetary damage then some fried networking equipment.

To say that a high voltage attack is the least of your worries is a complete understatement. If I have that level of physical access to your system, you have a lot more to worry about. Suppose, for instance, I invite my friends Messrs. Smith and Wesson along....

Comment Re:Oh, Christ, here we go... (Score 1, Troll) 223

I'm going to agree in part and disagree in part.

I'll agree: whining endlessly about microagressions (micro == 10E-6 == very small; what is there to whine about?) is counterproductive. It destracts from the real issue.

The Ada Initiative was spawned (in part) because of a very much non-micro agression. That is, a full, no-SI prefix, shoulda-been-a-year-in-jail-for-assault aggression. Hands in the pants is flat out unreasonable. Full stop, schlusspunkt... Period. Fucking. Dot.

I'm happy that you've not had such a problem. Apparantly you're batting a thousand; even as a guy, I've been harrassed. I don't want to speak ill of the dead, but one of the more senior employees at a previous job hit on me and then felt me up. "De mortuis nihil nisi bonum", and I've forgiven her long ago, but nobody should have to deal with that. And the rate of "dealing with that" for women in tech is far too high.

So, yeah, I agree in part and disagree in part. People should stop whining about stuff that doesn't matter; similarly we should pay attention to a real problem.

Comment Re:It's unfortunate they have to shut down (Score 1) 223

So, "its work to continue," is a misnomer then. It's more accurate to state that other organizations with similar objectives will continue to pursue them even though this organization has bowed-out. It's not like the closing of this organization is directly causing its resources and specific pursuits to be applied post-mortem.

You're correct: their donors and volunteers and supporters won't automatically transfer to another organization, and that this the most unfortunate part of the Ada Initiative shutting down. Hence, I feel compelled to suggest other, like-minded organizations. My personal favorite "best match" is the Anita Borg Institute, but ACM-W or SWE run close seconds (in my mind at least). Indeed, I met "Val Henson", and still have trouble remembering her name change to "Valarie Anita Aurora".... perhaps Val can chime in herself about which charity she would prefer people support, but I'd put money on ABI.

Comment It's unfortunate they have to shut down (Score 1) 223

I've met Valarie personally; she's quite driven, smart, and focused. I can understand how running an organization like that can be draining, and it's sad yet understandable why they're shutting down.

I might suggest, though, on top of the other organizations listed as successors to support, the Anita Borg Institute.

Comment Bureaucrats, so late, and still so wrong (Score 2) 157

I'm surprised it took this long for the bureaucrats to issue silly regulations. I mean, they're only 20 years behind.

Having looked at the proposed regs, they kinda make sense.... if every Tom, Dick, and Harry were to be driving a self-driving car. If any schmuck with a bit of disposable income had a self-driving car, then overbearingly specific regulations might make sense. However (outside of a perhaps very rare to nonexistent hobbyist (this ain't a cheap game)), all of the self driving cars are owned and operated by large institutions. Since these institutions 1) have deep pockets, and 2) care greatly about their reputation, I can write appropriate regulations in a tweet:

"Self-driving cars shall be bonded for 2 million dollars each against damage to life and property, burden of proof lying against the owner."

Tweak the amount per currency or the value you place on life as you see fit, so long as the amount of the bond is whinging enough to keep out rich fools.

Comment Worst ever serious language (Score 1) 166

When discussing stupid/nasty/unpleasant programming languages, INTERCAL and Brainf*ck typically come up. However, both of those are artificial languages designed to be unpleasant. They are jokes.

I wish MUMPS was a joke.

MUMPS makes both APL and BAFLL seem sensible. The classic DailyWTF article, A Case of the MUMPS, really explains it all. Including things like an 8 character function name limit (even C fixed that, although not before we got the "creat" system call).

MUMPS is just as bad as it sounds.

Comment Re:Bad sportmanship, or lawyers? (Score 1) 107

The even more disgusting thing is that the motor doesn't even need to be running to make a cross-channel flight.

The aircraft in question has a 15:1 glide ratio and a 16,000 foot service ceiling (per spec). That means it can do a 45 mile glide. At the Straights of Dover the channel is only 20 miles wide; that's a over a factor of 2 safety factor. Wind could be an issue, but if there are headwinds, they could run the engine to make the crossing against the wind, but abort backwards *with the wind helping them* if there were an engine failure.

I think this just confirms my dislike of Airbus; they've had a good number of shady dealings in the past, and given the extensive time period such things have gone on, I don't think that leopard is going to change its spots.

Comment A new plan to keep editors honest (Score -1, Offtopic) 172

Record when they F up. Because of course they'll silently fix it w/out notice.

Amazon has a new plan to keep authors honest: a href=''>they're only going to pay them when someone actually reads a page. Peter Wayner at the Atlantic explores how this is going to change the lives of the authors — and the readers. Fat, impressive coffee table books are out if no one reads them. Thin, concise authors will be bereft. Page turners are in.

Hence, a record. Seriously, just leave off the opening < on a href? And then post it?

Comment Re:Cut the write enable line? (Score 1) 145

A two minute check

A three minute check shows they claim a power savings over having no AV installed at all. They claim 4.43 KwH/day for no AV, and 4.39 KwH/day for Abatis. Unless there is some "new math" reason that 4.43 is smaller than 4.39, it would appear to me that they are claiming to have lower power than no AV.

Yes, surprise surprise, I actually RTFA... and not just skimmed, but truly read it.

"You must have an IQ of at least half a million." -- Popeye