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Comment Re:Recently in an airport. (Score 1) 196

They're checking for TATP or something similar, even though no sane person would carry it in liquid form.

You have it backwards. TATP is a solid explosive compound that can be produced from liquid acetone, liquid hydrogen peroxide, and an acid. If TSA is afraid of TATP, then it makes sense to check that people aren't carrying hydrogen peroxide.

Comment Re:Probably Not Enforceable Anyway (Score 1) 260

My practice with hotels is to find the cheapest one available, and then only sleep there. ... What do you do with hotels that requires you to actually study up on reviews beforehand?

I followed this strategy plenty of times and my experience is that I will end up with a smelly room (body odor and/or smoke absorbed into the carpet and curtains), excessive street noise, a half-broken water knob(*) in the shower, noisy/drunk neighbors who also went for the cheapest option, and/or a really greasy breakfast.

I would actually prefer to stay in a hostel, but alas my SO doesn't like the idea of bunk beds and shared bathrooms.

(*) Why does each and every hotel bathroom have a different system for adjusting the water flow and temperature of the shower that involves unlabeled knobs and that requires two minutes of fiddling to figure out?

Comment Re:Android (Score 2) 31

The problem with Android permissions is that a lot of apps request internet and sdcard access and there is no way to know what kind of data is going to be exchanged. Benign usage would be downloading ads and dynamic content, for the apps that are just a wrapper for a website. But for all I know, an app could be scanning the sd card for interesting data and feeding it to big brother.

Comment Re:1 in 1000? (Score 1) 49

"... if they took the 22,000 wire tap orders and an estimated 22 million phones and came up with that figure. That may not be accurate."

The letter states that there were 25k wire-tap orders over 2012 and that this is explicitly not the number of suspects, since some suspects use "very many" phone numbers. The letter doesn't mention 1 in 1000; that's the media spin on it.

Why does slashdot post an artocle about Netherlands at midnight local time?

Comment Irish tar (Score 1) 142

I just returned from holiday in Ireland and apparently temperatures were exceptionally high. One day, my shoe soles were essentially paved (they looked like road surface) because the roads I had walked on were molten. I wonder whether this droplet has anything to do with the weather conditions.

By the way: exceptional weather means a week of sunny weather with 24-28 degrees C temperatures. Irish asphalt is probably optimized for cooler and rainier weather. :-)

Comment Re:I liked the thing (Score 1) 550

word processor that you're using that does all those things BETTER than MS Word

The main difference with some of my coworkers is that I note the problems myself, curse, and fix them before asking someone else to read my work. Over time I found a work flow that tends not to generate too many issues (print to PDF via cutePDF, avoid copy/paste of text with references as much as possible, don't deal with the equation editor, don't convert back and forth between .doc and .docx).

And if I write something with lots of equations and I'm sure that coworkers will not need to revise future versions (i.e. a write-once document), I do it in LaTeX. That has its own set of disadvantages, but I find myself cursing a lot less if I use it.

Comment Re:I liked the thing (Score 1) 550

... anti-ms trolls are always careful not to include a SINGLE fact ...

The documents that we deal with here contain company-secret information, so I am not going to share any problematic documents just to convince you. However, I can tell you that they are usually rather old (Office 2003) macro-enabled templates that are now being used with Office 2010. I'm sure the "error reference not found" result from bad copy/paste actions by the user, but I consider it an design error of MS Word that I never see any warning about broken references.

By the way, libreoffice (my version is about 2 years old) invariably chokes on our company Office templates (Word, Excel, Powerpoint) as well.

Comment Re:I liked the thing (Score 4, Insightful) 550

Also, Word works reasonably well. For example, right now I have a nearly 80,000 word document that it handles well enough

Strange; where I am sitting, I hear of and see endless numbers of problems with Word with my colleagues: Word crashing on or garbling documents with too many floating figures, equations that suddenly turn into un-editable bitmapped images, documents full of "Error reference not found" (try remembering exactly what you wanted to refer to a month ago...), "save as PDF" generating pages with a gray toner-wasting background.

Comment Anti-reflective with fingerprints? (Score 4, Interesting) 175

Anti-reflection coatings by themselves are nothing new. AR coatings that are scratch-resistant might be more tricky. But I would be really impressed if they can make it anti-reflective even when covered with fingerprints.

AR coatings are based on thin layers with thicknesses tuned and accurate to 20 nm or less and well defined refractive indices, matched to the refractive index of the air on one side and the glass on the other side. It's hard if not impossible to make a coating that keeps working even with an undefined number of micrometers of skin grease on top.

My glasses (eyewear) have a very nice AR coating, but fingerprints turn it into a colorful reflector.

Comment Re:Too Bright (Score 2) 924

"I ALWAYS turn my phone and any other devices COMPLETELY OFF at important events"

I used to have a Nokia N82 that would wake up from the "completely off" state to sound an alarm. Only removing the battery would do the job.

Fortunately I didn't discover this while attending a concert (or worse: while being one of the performers in a choir).

I'm actually not sure whether Android doesn't do this. Nowadays I always check that there is no alarm set at an inconvenient time before going to silent mode.

Comment Re:Simple panoramic camera? (Score 2) 108

"to use a single, vertically oriented digital camera with a hyperboloid mirror in front of it,"

Assuming that you mean a camera with a lens looking into the hyperboloid reflector: that would not work because such a mirror would not produce a real or virtual image plane onto which the camera could focus. Parabolic or hyperbolic reflectors can only image a point to another (virtual) point, not a plane to a plane.

In other words, you get a blurry image; in order to unblur, you would need to know the angular distribution of light intensity on each pixel; if you had such a sensor, you could just as well leave out the lens.

The blurring might be manageable if the lens is small (like a phone camera) and the reflector is very large (like a meter), but then you'd run into problems with sensor noise and resolution for a 360 degree image and there woild be no gain in portability.

Comment Re:Coal ash is highly radioactive (Score 1) 319

There was a "study" that claimed this (coal power emits more radioactivity), but for the comparison they took the most radioactive coal that exists, orders of magnitude higher than average.

Moreover, there is no point in comparing against emitted radioactivity from a correctly functioning nuclear plant, as it is pretty close to zero. The problem is when a nuke breaks.

Comment Re:Mass and Weight are different (Score 2) 78

force equals *mass* times acceleration. ... the acceleration would be the same but the force experienced by Curiosity's tires would be ~3x larger (ignoring any shock absorption).

You do have a point -- I don't agree with some of the other responders who talk about traction forces being smaller as well. Just to make it clear: what you say applies to a cart on wheels, having constant horizontal velocity and approaching a bump in an otherwise flat surface. A larger mass of the cart will result in a larger force at the wheels the moment the cart hits the bump, regardless of gravity.

However, this force is roughly F = m v^2/L, where v is the horizontal velocity of the cart, L is the travel of the suspension, and m is the moving mass. The moving mass can be just a single wheel; in that case L is the leeway in the tire rubber (less than a millimeter), or m can refer to the entire car, with L the travel of the wheel suspension.

Now, the issue of inertia is only relevant if the instantaneous extra force is larger than the gravitational force. Given that this Mars Rover has a maximum speed of 0.025 m/s, the maximum inertia-driven acceleration is about 1 m/s^2, even assuming only 0.5 mm of suspension travel. This is much less than the gravitational acceleration (10 m/s^2); therefore inertia does not make a significant difference in the wear on the wheels.

Comment Re:So many extra fees (Score 1) 91

In Europe ... So no tipping in many places (or minimal tipping) as people get payed by their boss for the work that they do.

You can't generalize that across all of Europe, unless "minimal tipping" means anything less than 15% in a restaurant. Tipping conventions vary quite a bit over Europe (based on the travel guides that I've seen). And for instance, in the UK, the 10% service charge on restaurant bills seems to be optional in some cases, although I don't visit the UK often enough to grasp the substle details here.

Comment Re:psst... your ignorance is showing (Score 1) 1105

Probably you as an AC won't read this two days later, but I don't understand why you changed the subject from "in the 1490's" into the present one, in response to my post. The original subject is a reference to Columbus (that's earlier than Galileo) and in that era the only other Christian church would have been the Eastern Orthodox church.

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