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Visibilty testing server side is very straight forward it's not a hard problem. You just need basic representation of geometry via bounds and test for line intersection.

That's not based on research, that's based on actually implementing it for real games.

This is so not even close to reality. See this Stack Exchange comment for an explanation https://gamedev.stackexchange....

Additionally read answer 2 here.

I do not know Esperanto, but have had some interest in its history, adoption, and current state. I do rely on the analyses offered by others of evident expertise.

So I was in a math mood...

The most accurate looking Monopoly money template I could find in a quick Google image search has 12 bills per 8.5x11" page. Assuming you go all $500's, that's $6000 per page. $100B / $6000 = 16,666,666 pages. That's 33,333 reams of paper. Quick Amazon search shows $5.97/ream (it's an Add-on item, but I think we'll make the minimum order here). So that's about $199,000 worth of paper for $100B Monopoly money or an exchange rate of 0.00000199.

According to Stack, a ream is around 5lbs (which matches Amazon's shipping weight) and paper yields about 7000 BTU/lb or 35,000 BTUs per ream (which seems high, but second source). They're claiming that's "enough to heat the average US house for 15 weeks" which seems implausible to me? Maybe if you're assuming 100% conversion efficiency with no losses and not living somewhere the air hurts your face.

So that pile of Monopoly money yields around 1,166,655,000 BTUs or about 12,820 gallons of propane and weighs 166,665 lbs (83 tons).

If nothing else, I suspect it would hold value more consistently than most crypto coin.

Apparently it is news to people that the Irish have Semitic and North African admixture

This is true even of their traditional languages. Irish is Indo-European, while Semitic languages are in the unrelated Afro-Asiatic family. Yet the Celtic languages of Britain and Ireland share several key grammatical features with Semitic languages. Perhaps these features were shared alongside the mixture of genes.

Your friend obviously has not heard of the programmer's goto (pun unintentional) site StackOverflow or the other StackExchange sites, else he might have been able to google this post from way back in 2013 :-).

Captcha=gravely

Your friend obviously has not heard of the programmer's goto (pun unintentional) site StackOverflow or the other StackExchange sites, else he might have been able to google this post from way back in 2013 :-).

Captcha=gravely

But no one says "I received 3 mails this morning,"

The reason being mail is the SERVICE that delivers letters and parcels. You'd say "I received 3 letters this morning".

I hate to break it to you, but the rest of the world considers email to be both uncountable in the case of email as the SERVICE that delivers the email and countable as in the emails(nobody calls them letters) that is delivered via the uncountable email service.

This link explains it better than I can Explaination for emails

Prescriptivism isn't something that English speakers take kindly to you know ;)

Interestingly even at 50-60Hz it seems like it does have an effect

http://circuitcalculator.com/w...

It's 9.81 mm at 60hz, 10.7 mm at 50Hz, though if you use the formula on wikipedia you get a slightly different answer of 9.22 mm, but I'm too lazy to look it up in a proper source.

https://en.wikipedia.org/wiki/...

In Engineering Electromagnetics, Hayt points out[page needed] that in a power station a busbar for alternating current at 60 Hz with a radius larger than one-third of an inch (8 mm) is a waste of copper, and in practice bus bars for heavy AC current are rarely more than half an inch (12 mm) thick except for mechanical reasons.

If you look at these high power cables, it looks like they're made of a bunch of smaller cables, each with a diameter of about 8-10mm.

https://electronics.stackexcha...

Well, if doing so at the cost of user experience, then you can lose some users. https://bitcoin.stackexchange.... It's roughly $0.37 USD per day.

How to render the SHA-256 Pre-image collision attacks effectively moot: Check the Fucking File Size.

The attack I'm concerned about doesn't involve a hash collision. The attacker who intercepts an HTTP connection can replace both the disk image with a replacement of the same size and the hash with the hash of the replacement image. And this interception (sometimes mistakenly called "transparent proxying") is much more difficult with HTTPS than with cleartext HTTP.

This will just increase the cost of entry

Increasing the cost of interception to where only nation-states can afford it and there's evidence if they do it anyway is the entire point of HTTPS.

Read up on generators and how demand influences frequency.

When you're done, go read some man pages. It astounds me that someone will take the time to write a post, but not take the time to actually answer the question that was asked. How that is that insightful?

Two different purposes. Most people aren't going to learn a damn thing from reading a man page from front to back, unless you needed to run a command and don't remember the switches. Spending a half hour reading a wiki page would likely give someone a pretty good high-level understanding of a subject. To your point though, maybe a link to some material to read would have been a little more helpful. But literally googling "generators and how demand influences frequency." produces a number of links on the subject, this being the first one: https://physics.stackexchange....

I'll pitch in $10.

Flat-Earthers make me feel the way I'm sure I make climate alarmists feel, but I believe in science (the process), and I'm willing to put a few bucks towards an independent verification. And maybe a bigger factor is that if a schmuck like this can get to space, that can only mean the day is getting closer when I can too.

What does this guy have to do with science?

Back when he just wanted a rocket ride then his first test would have been a ride on a standard commercial hot-air balloon. Of course that wouldn't have been high enough as you apparently need to be about 10k up.

So now that he's apparently done the dedicated research of a 5 minute google search he's realized his rocket (which he backed out of) wouldn't get high enough, but instead of testing his hypothesis by sending up a camera for a few thousand he wants a couple million to play pretend astronaut.

He's not trying to do science, science is about trying to honestly investigate and verify your ideas. If he really was a scientist the first thing he'd do is ask a friend to hop in a sailboat and watch for a few hours, when the sailboat vanished over the horizon, exactly as predicted, he'd go "huh, so I guess the earth is round after all". Of course, if he came up with some dumb excuse for the ship vanishing like oh, it's just too far away I need a telescope then it would immediately occur to him to make two observations with a telescope, one close to sea level and one on a sea cliff. And again he'd disprove his flat earth hypothesis.

I don't believe this guy is such an idiot that I only needed 30 seconds to come up with experiments that never occurred to him in a lifetime of scientific research. Rather, I think this guy isn't a scientist, he's just a religious believer playing science, and he's deliberately avoiding doing anything to challenge his beliefs. Plus if he can get his name in the papers and bilk a bunch of people out of money that's just a bonus.

No, that's not what the study said.

https://skeptics.stackexchange...

"So having a tracker seems to make you fatter (compared to the study control group)."

Beyond that, as has already been pointed out multiple times, "fitness trackers" are worthless. They give people a false sense of how "active" they are, which causes them to be less active than without the tracker.

No, you're completely misrepresenting the results of the study. The comparison studied wasn't "fitness tracker" vs. "no fitness tracker".

It's just that the approach that required people to take their own measurements, enter them into a website themselves, and then receive intervention phone calls from the staff members, was much more successful than using the fitness tracker alone. But even though that's the case, both approaches were successful in losing weight. It's just that the second approach had participants lose more weight than the fitness tracker approach.

Also, keep in mind that the study was started in 2010, so the fitness trackers used in question were probably not that advanced to begin with.

http://skeptics.stackexchange....

No, that's not what the study said.

https://skeptics.stackexchange...

This article is missing all the context to this debate. Google sent the email in response to the Indian "Hike" messenger (now the #1 app in India), which came up with a creative use for Accessibility permission to make the app go viral at the click of a button on top of other social networks including WhatsApp.

Before they used this trick they were nowhere near the #1 spot in the Indian app store.

Flight hours only count parking brake to parking brake, if I recall correctly. Crews work more hours and spend time traveling to hubs that don't count as flight hours. Depending on the schedule a pilot could use h=their hours in a few multi day trips, after allowing for required crew rest. Training is also not counted for legal hours flown.

Cite: https://aviation.stackexchange...

He can always plead that he thought it was supposed to be in that mode to work properly. Toggles seem to be notoriously hard to design so as not to create confusion as to which state it is in.

should be safe

openssl rand n does use /dev/urandom on a Unix like OS, but it doesn't just directly read n bytes from it, it does a bit of munging, like reading a few bytes at startup and using that as a seed for its own PRNG.

https://security.stackexchange...

And of course openssl works on OSs that don't have a /dev/urandom at all - e.g. on Win32 it calls Win32 crypto function to get a seed and then uses that for its own PRNG.

Basically the openssl guys don't seem to trust /dev/urandom to be random. E.g. the stack exchange source says

You do not want to trust that the random source is random. /dev/urandom in particular is not trustworthy because in guaranteeing that it wiill not block on low-entropy conditions, it fails to guarantee that the output is actually random. The manpage man 4 urandom has more information on this, including a cryptic allusion to an attack some government body may or may not have predicated on this condition. Suitability tests can be conducted on this data, or it can be mutated in some way to concentrate entropy, or different sources can be combined.

Which I think is a reference to this

https://linux.die.net/man/4/ur...

A read from the /dev/urandom device will not block waiting for more entropy. As a result, if there is not sufficient entropy in the entropy pool, the returned values are theoretically vulnerable to a cryptographic attack on the algorithms used by the driver. Knowledge of how to do this is not available in the current unclassified literature, but it is theoretically possible that such an attack may exist. If this is a concern in your application, use /dev/random instead.

And essentially running the output of openssl rand through sha512 a couple of times does a bit more munging. And running it through sha512 a random number of times and then encrypting with a per device RSA private key does even more munging.

As with most things in life you have to decide what level of munging you feel comfortable with and code to that level. Personally I use the maximum level, though of course it's debatable whether this is overkill or not.

It may well be that just reading from /dev/urandom on your OS is good enough.

In baseball, the criterion is the ball's angle of travel across the plate. Ideally you want it so the batter can't get a clean look at the ball, and so his bat can't make square contact.

https://sports.stackexchange.c...

It isn't open to argument, though I do concede it is common for people to be confused about this. If one to were define emulation the way you are defining it then every C++ compiler that implements the STL would be an STL emulator. WINE implements the Windows API. It does not emulate it. You can learn more about the difference between emulation and implementation, specifically as it relates to WINE, here.

Older Macbook Pro have this "feature", too, with their 85W power supply. Happened to me on my 2012 15" Macbook Pro, and it seems I was not the only one. For example, just a simple Google search shows discussions like https://discussions.apple.com/... or https://apple.stackexchange.co...

Some of the open-source software I wrote ...

You may consider it "open-source", but it's not really "open source" in the sense that most people think of the term. That is, your license does not conform to the Open Source Initiative's definition of "open source" (in particular, it fails Point 5: "No Discrimination Against Persons or Groups".) Such "crayon licenses"* severely hamper other people using and building on your work. Anyone who wants to use your work can't do so in any environment where it needs to be Open Source or Free Software.

That may be okay with you. You might not care that people can't use it that way. That's fine: it's your software, and you're free to license it however you wish. -- Just be honest with yourself and others. It's not really "open source". It's a proprietary license which just happens to permit people to redistribute the source ("source available" rather than "open source"). Attempting to grab some of the Open Source/Free Software movement's laurels by claiming it's "open source", though, is a bit too much.

* And yes, a "modified BSD-license with some additional restrictions" is no longer a BSD license - it's a crayon license

Other than the fact that it has been extensively security reviewed by independent people...
https://security.stackexchange...
https://www.androidauthority.c...
https://www.reddit.com/r/linux...

Why not shut spotlight down or limit it through settings>Spotlight>Search results/Privacy? If it's _that_ bad it's what I'd do.

Been there, done that. I don't use Apple Mail or any of the apps it wanted to index, so of course I turned those off; same for iCloud. I do use spotlight, so shutting it down entirely would not be an option.

You _have_ attempted to see if a clean install (with no apps/files copied over) has the same issues?

Well, then the 2011's GPU died, and I couldn't get it to boot into a usable state to get files off of it (I did eventually pull the drive and get at the files before wiping the drive and installing Ubuntu on it) and I ran out and bought this machine, that's how I started with this machine. I expected indexing and whatnot for a couple of days, especially given that I the first thing I did was install my IDE (fresh copy downloaded form the vendor) and clone the rather large Git repo I was working on; I also expected that to die down within a week and it did not.

I don't think you get much cleaner of an install than a freshly opened box. This has been an issue from day 1.

Further tests by manually adding in your files and then apps gradually?

Indeed, as explained above I didn't immediately pull the drive from the 2011; I installed just what was needed for my work. When I did pull the drive, a couple weeks later, I used it as an external (USB) drive for a while to get a feel for what I might actually need off that drive and was very selective in what I kept.

Are you sufficiently technical to use dtrace?

Given the nature of my work, I should hope so. Given the fact that I needed a system I could do actual work on and not a full-time maintenance job, the Mac became a secondary machine by the time I might have cared to dig that far into it.

Have you attempted to reset the SMC? Some weird problems can be SMC related.

SMC and PRAM both, for unrelated issues.

As for the powerd issue, well, I'm not the only one seeing it. In fact, a lot of people are. Likewise for the issue and kernel_task RAM and CPU usage.

Given how you are seeing strange issues I begin to wonder if you might have a problem with stowaways.

You mean malware? That thing we've been told over and over doesn't exist on Macs? I'd find it quite ironic if that were the case, given that I have a security background myself and have never had an issue with it on Windows, despite that platform's reputation. That said, I have never seen any odd processes running and rkhunter and clam both report a clean system. I ditched clam and ran WebRoot for a while but it caused its own issues -- but also reported a clean system.

If, by stowaways, you mean holdovers and cruft from a prior OS installation, unless it came that way from the factory we can rule that out right out of the gate. I haven't upgraded this machine past Yosemite, which was the current version when the machine fell out of daily use; and I had these same issues on Mavericks, which the machine shipped with. Yosemite was a clean install, as well.

I'm about to repurpose this machine, so it may see High Sierra (also as a clean install) soon. We'll see if that fixes things, but I won't hold my breath.

That said, Linux does not belong in safety systems, and I hope it never ends up in ... spacecraft.

Too late. Linux is already the Falcon 9 spacecraft.

I found it interesting when I read that the SEC considers it NOT insider trading to cancel an order based on insider information.

See an article about it here:
https://space.stackexchange.co...

Because theoretical physicists say they have mathematical proof you can, in fact, stop aging

3. Connect your smartphone or tablet to the Internet.

Not everyone has WiFi I'm afraid. Still locked out.

If cellular is unavailable, and WI-Fi is unavailable, the remaining option I can think of is wired networking. This can be done in one of three ways:

A. Plug a USB OTG NIC into the phone and an open Ethernet jack.
B. Plug a battery-powered access point into an open Ethernet jack.
C. Plug a USB cable into the phone and friend's computer, tell the phone to emulate a NIC, and tell the friend's computer to bridge the connections. Here, the phone is using the PC's Internet connection, unlike tethering which is the other way around.

As I wrote earlier, I concede an advantage of TOTP over SQRL in situations where neither the cellular network nor the existing WLAN nor a battery-powered WLAN nor a USB NIC nor sharing of the PC's connection is possible. But how often will end users encounter all five of these situations?

3. Connect your smartphone or tablet to the Internet.

Not everyone has WiFi I'm afraid. Still locked out.

If cellular is unavailable, and WI-Fi is unavailable, the remaining option I can think of is wired networking. This can be done in one of three ways:

A. Plug a USB OTG NIC into the phone and an open Ethernet jack.
B. Plug a battery-powered access point into an open Ethernet jack.
C. Plug a USB cable into the phone and friend's computer, tell the phone to emulate a NIC, and tell the friend's computer to bridge the connections. Here, the phone is using the PC's Internet connection, unlike tethering which is the other way around.

As I wrote earlier, I concede an advantage of TOTP over SQRL in situations where neither the cellular network nor the existing WLAN nor a battery-powered WLAN nor a USB NIC nor sharing of the PC's connection is possible. But how often will end users encounter all five of these situations?

Here is a perfectly cromulent explanation of what the expression means, and where it came from: https://english.stackexchange.com/questions/34793/what-is-the-origin-of-the-phrase-cut-and-dried

The use of past tense is important to the explanation in that 'dried' implies completion where 'dry' does not.

"I guess if you are going to make electricity dangerous, you might as well go all the way."

Mate, domestic 120V is just as lethal as domestic 240V.

An [unreliable] source.

Even if you can cross-compile, you can't ensure that the cross-compiler binary is free of Ken Thompson's self-propagating "trusting trust" attack unless you bootstrapped it from an independently developed compiler.

Here:- https://scifi.stackexchange.co...

Actually, you could generate artificial magnetic shielding for Mars using a specialized craft at its L1 Lagrangian point. Expensive as heck, but doable and involves technology and structures available today and not some impossible megastructures, but something sized more like Skylab.

After the American media helped to drum up preparation for the war in Iraq, completely spun up and twisted upside down most issues related to say war in Syria, and took decisively the side of the Democratic presidential candidate last year, I sure can certainly trust our mainstream media a whole lot these days.

I think in the not to distant past, the fourth estate could get away with influence-peddling without too much effort. When the wealthy & powerful began consolidating marginally profitable news outlets, it should've been clear to even the casual observer there was possibly some ulterior benefit.

Has the 4th estate lost power to the 5th estate because of their complacency? Traditionally successful periodicals seemed slow on the uptake; "This internet thing will never catch on."

They certainly didn't diversify the information delivery method as fast as their competitors.

In terms of fuel economy, large airliners beat cars in fuel consumption per passenger-mile

We aren't talking about airplanes. We are talking about something that'd need to fly slower than an airplane most of the time and hover a decent part of the time. In other words, a 'copter of some sort.

Plagiarized from a Aviation Stack Exchange,

When helicopters are traveling slow, they need more energy to hold their weight. When traveling fast (according to their standards), the rotor drag is very high. This is the primary reason they need more power. More Power = More Fuel.

Conventional aircraft have much less drag at a given weight and speed than a chopper.

Helicopters travel slow. When they burn more fuel per hour and travel slowly, fuel consumption per mile is much worse. They also stay low. Most have turbine engines, turbines burn lots of fuel at low altitudes.

https://aviation.stackexchange...

I assume the concern for the size of the leak is that with a large leak, the "emergency air supply" will run out quickly? Nonsense.

Learn a lesson from aircraft cabin depressurization response, and run the emergency air supply to face masks.

If you don't try to keep the whole cabin pressurized, you (a) don't fight whatever caused the loss of pressure in the first place, and (b) don't continue adding air into the tube outside the passenger compartment, which has the double bad effect of increasing drag (not really a problem for the amount of air leaking, considering the huge volume of the tube) and turning every leak into a mini-thruster which may be forcing the opposite side of the capsule to drag on the tube walls!!!

I think the problem isn't the lack of oxygen but rather the lack of pressure. A facemask would only be effective if you can keep the cabin pressure above 120millibars and likely needs to be even higher than that to avoid fatalities: https://biology.stackexchange....

Here is a link to a question that sheds some light on aspects pretty much always overlooked in discussions. Most people don't seem to understand what the issue is because very few people participating in these discussions own patents or ever thought much about it.

https://law.stackexchange.com/questions/14337/q-about-consequences-of-a-software-license-amendment-regarding-patents-facebook

Basically, the issue is this:

If a company, let's say a biotech company, owns patents - not on software, on _anything_ - finds that Facebook infringes on their patent they cannot sue them if they happen to use one of Facebook'S projects. So if Facebook were to start a spinoff that uses IP from the biomedical company they can do so, they wrote a blank check fro themselves. You have to trust them not to do that.

The above is not a statement of fact, it's the question that still is open (see link). The one answer there from yesterday (the Q itself is from Oct 2016) does not actually answer it either.

capitalize "Physics" it is a subconscious clue to readers that you're nuts.

You assume that someone is crazy just because of having written "Physics" rather than "physics"? Can you understand irony or is it too difficult for you too?

Additionally, that capitalisation rule doesn't seem as evident as you are suggesting. Apparently, it is a matter of context and "Physics" might also be valid. BTW, I only believe in science and in what I can reasonably explain, but have no idea how to explain consciousness; In fact, nobody can. Accepting the limitations of our current understanding is pretty much the opposite of believing in magic. On the other hand, not accepting that fact and blindly assuming that science can certainly explain whatever issue does seem to suggest a magic-prone attitude.

The MITM could insert malicious code into files transferred through FTP. Even if the file looks like a video, several video containers such as WMV have contained functionality to download DRM code to obtain a license needed to decrypt the video in the WMV file. This functionality can be and has been used for dropping trojans.

I do in fact.
Here's a citation:
https://en.wikipedia.org/wiki/Entropy_in_thermodynamics_and_information_theory#Information_is_physical
and the relevant portion:

Using a phase-contrast microscope equipped with a high speed camera connected to a computer, as demon, the principle has been actually demonstrated.[3] In this experiment, information to energy conversion is performed on a Brownian particle by means of feedback control; that is, synchronizing the work given to the particle with the information obtained on its position. Computing energy balances for different feedback protocols, has confirmed that the Jarzynski equality requires a generalization that accounts for the amount of information involved in the feedback.

Additional links:
http://physicsworld.com/cws/ar...
https://physics.stackexchange....
https://www.newscientist.com/a...

-natch

When there's a "working from home" option, you're one step away from being outsourced.

Personally I enjoy going into work. I like my coworkers, I find that some collaboration in-person is extremely important, and working from home is distracting.

You haven't met the "Help Vampire" yet.

I can't say that I agree or see anything that's inherently better about Fortran than C.

Assuming that by 'better' you mean resulting program running faster: array handling and lack of opaque pointers.

In C, array is just a memory block with bit of fancy access syntax. In Fortran, array is a a construct understood as such on compiler level and because you cannot do so many tricks with pointers, compilers is allowed to do certain optimalizations impossible in C. Example - it can change layout of array to better fit cache lines on CPU.

https://scicomp.stackexchange....

Yes, contemporary C compilers achieve a lot - but it requires a lot of handcrafting (tagging memory blocks with builtin_aligned etc) and trial and error (sometimes innocent looking line can change your code from 4-way optimized vector code into old MMX era style due to some compiler quirk). But even with that, cache layout optimalization is left for you to do manually (and you end up seeing code with things like pad0,pad1,pad2,pad3,pad4 etc).

1. The US has plenty of state-funded institutes of higher education. In fact, many of the top US universities are state-funded (probably even state-owned although I'm not sure).
2. "Cheap" in what way?
3. Costs of private higher ed are also "socialized" but in a different way: They're covered by a group of people with typically no savings nor sufficient income - young students. In my humble AC opinion, that's ridiculous and sad.

Finally, you can say many things about the education systems of various European countries, but they do seem to do a better job in terms of assuring people are not totally clueless.

First, ob disclaimer (in Bones' voice) : I'm a doctor, Jim, not an orbital mechanics expert.

all by itself unless acted upon by an outside force.

- That's the whole purpose of the ISS being in such a low orbit : there's still a significant (although extremely tiny) outside force in the form of atmospheric drag.
This has the immense benefit that this orbit is more or less cleaned of debris thanks to the drag.
But it also means that the ISS needs to regularly do compensations.

- There might still be other outside force that are necessary :
I suppose that once in a while, ISS must do small correction of its orbit to be sure not to be on a collision course if the debris observation network notices one not yet cleared debris of significant mass/size.
(Now, I don't have the faintest idea how much time in advance are these dangerous objects detected, and thus how long is the window of opportunity to do the manoeuvre so that later, once the ISS and the debris are in close vicinity, the risks of collision have been successfully reduced under the acceptable limit by the earlier manoeuvre).

- Last but not least : I'm pretty sure that the maintenance of the complex equipment (including all the various life support systems) is not just a lone astronaut's job but is a big team collaboration involving all the people directly in the station AND all lots of people on the ground. The non availability of ground crew can probably make some class of problems that might happen much more difficult to solve for the small crew currently in orbit.

https://skeptics.stackexchange...

Saying he lied on his resume, he's not a PhD, etc: https://chess.stackexchange.co...