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Comment Re:Overboard, Sad! (Score 1) 206

The ability for something to do damage depends on it's momentum, and that is highly dependent the mass and centre of gravity of the object as it applies force against something. You do a 1kg drone a serious disservice comparing it to an iron mallet. A drone is a complex shape and its weight is distributed over a comparatively large area. While crashing it will be taking a complex path to the ground. When comparing the likelihood of it killing you remember it's far more likely to be the same as a falling iron mallet, horizontally, hitting a person by the handle rather than the iron centre part. You're far more likely to get a bruise from the mallet's handle.

Not really. The primary cause of momentum is the acceleration from gravity which is essentially constant for a falling drone, air resistance is just a counter-force proportional to the velocity squared. That is to say, the reduction from air resistance only becomes significant when you're falling very fast. A skydiver has a terminal velocity of about 195 km/h, but already a high diver from a 30m height will be close to 100km/h. I know my buddy's DJI Phantom goes up to 120m by default, at that height you'll be at 90% of terminal speed. Unless it's extremely small or light like a feather or a coin, any object dropped from a big height is a lethal weapon. When the rotors stop the body of a drone is quite compact and holds a heavy battery, it'll fall pretty much straight down. You can see a good example of a drone coming down after a complete power loss here.

As for the actual impact the higher the velocity, the less it matters how it hits you or how soft or elastic it is, a stick of butter dropped from a skyscraper will still hit you like a brick. We have a pretty thick skull but the sheer momentum will be like being hit in the head with the full swing of a baseball bat, your brain will bounce around in there like the ball in a pinball game. Sure there are arguably worse things to be hit by, but for the most part we secure tall objects. There's falling coconuts and big icicles and such we can't fully control, but drones are a new threat in the hands of idiots. They're not very dangerous, but in the hands of idiots many things are dangerous.

Comment Re:Lottery? (Score 1) 160

Is there a legal reason SpaceX can't have a lottery for tickets? Seems like a good way to fund these types of things.

Well what do you do if you don't sell all the lottery tickets, is the lottery stuck? Normally the prize pool is relative to the total paid in, but either you get a seat or you don't. Also you might end up with people that for medical or mental reasons shouldn't be trapped in a tiny little space capsule for a week with no chance of assistance, sure you can disqualify them in the terms and conditions but the whole "my number came up, but I was refused" bit would be negative PR. And it's just one lucky winner, in a regular lottery people like to win a little now and then while they hope for the jackpot. The rest will really be trinkets by comparison.

And I think this is still just a joyride, not a life changer. You take a fling around the moon and then you're right back to where you were, sure it's for space nerds but hardly the mass market appeal an ordinary lottery has. I think it would be totally different if it were say a ticket to Mars. That's the kind of thing you could probably make a living off afterwards, just from selling interviews and speaking engagements and such. Then again you'd probably want to be more selective in the selection process so... I mean it would be cool, but I understand why SpaceX wouldn't do it. And it's easy to get their lottery confused with (semi-?)scams like Mars One.

Comment Re:Always Assuming... (Score 1) 135

I can't decide if you're high, crazy, stupid or just trolling. Let's just unite under one Führer, that worked so well the last time. Because what we have is clearly an anarchist's dream where everyone does exactly what they want, no laws or regulations to hold us back. And the richest parts of the world that could support the most kids have women go crazy to have a little league team each. My guess is your sarcasm meter is so broken you'll think I'm serious.

Comment Re:Isn't all of this just BS? (Score 1) 220

as far as I understand AI, it's basically plugging the program to a (insanely huge) database about the subject and help him interpolate the input and it's own data. That's computer program getting better, not getting "intelligent". Or is my definition of "AI" that off the mark?

Well it depends on how much you consider "MacGyver" style problem solving to be intelligent. As in I have a task to complete, I have a bunch of random items that can be combined/used in some way to produce a non-obvious result. Computers are great a combinatorics even to the point where they might do something that's original and never been done by a human. A lot of what humans consider creative is putting together known things in unexpected ways, or at least that this particular person has never done before. You might say that the computer is always in the box but we're trying to expanding it while at the same time guiding it so it doesn't get lost in an endless number of possibilities.

Maybe it's easier to explain with a practical example, before you gave the computer a toolbox and taught the computer that the the hammer could hammer, the saw could cut and the screwdriver screw and that was the box. Then we gave it free roam as a few hunks of wood and metal and it got totally lost. Now we give it examples of people hammering and cutting and screwing which guide it, but doesn't bind it. And we find that sometimes it does things in novel ways because nobody told it that it couldn't. The goal is to make "the box" the laws of nature, physics, chemistry, gravity, optics and so on. That we stop defining for the computer what something is and what it can do.

Comment Re:No surprise... (Score 1) 218

Intel appears to edge out in single core performance, but by less than 5-10% depending on processor and we still haven't seen single core performance of Ryzen 5 or 3.

Well so far AMD has intentionally only compared their own 8C chips with Intel's 8C desktop chips that have been clocked very conservatively, all the good chips go to the way more profitable server market and not against the far more price-similar quads. So the quad core i7-7700k is still king of the hill in single threaded with Ryzen 1800X trailing offering about 80% performance (2.02 vs 1.62) in Cinebench single threaded. Of course 8x80% is much more than 4x100% so if your applications use multithreading well Ryzen leaves the 7700k in the dust by a substantial margin. It will be interesting to see if they can bump frequency further on quads, it's a bit the Phenom x6 again with more cores at lower speeds. But a much better attempt at that.

Comment Re:Good grief (Score 2) 332

SLS is up to 2.5 times the LEO capacity of a Falcon Heavy, which SpaceX has never actually launched. SLS is in a different class.

The block 2 version that's at least a decade away, yes. The one they plan to launch late next year is in pretty much the same class (70 vs 54 tons), by the time the 130 ton version is ready SpaceX should have a Raptor-based competitor to match. Maybe not ITS-size, that's a bit megalomania (300 ton reusable, 550 ton expendable) but even a "Raptor 9" would give NASA a run for the money. But yeah... I want to see the Falcon Heavy fly now too, it's been pushed back quite a few times.

Comment Re:This won't fly. (Score 1) 281

The proposal is only a wipe. If this happened accidentally you can log back into icloud or your google account and resync. Crisis averted.

So to protect all your information, put it in the cloud. The NSA loves you.

How would they know the code?

Well what should happen when you type the wrong code over and over? Here it's company mandated that four wrong attempts = wipe. Somebody's figured out the hard way what happens when the kid gets hold of your phone, bye bye vacation photos (abroad, too expensive to cloud sync).

Comment Re:Maybe, but maybe not (Score 1) 322

Sure but my Uber account works in 20+ countries worldwide, I don't have to sign up for the local transit whatever. That's a huge plus. (...) As someone traveling in Hawaii, California, Texas, London and Hungary might be in a niche market. Everything you said about billing sure but for most people most the time it's a very limited geographical area. You can search for "taxi <city>" and install the local app ten times waiting to get off the plane, not that airports lack taxi queues. And I usually pay by a credit card that's linked to the travel and expense system no matter what the currency is, it not only works for taxi rides it works for everything else. I'm not saying it's not nice to have... but in terms of make or break for Uber's business model I think it's totally irrelevant.

Comment Re:Too good to be true. (Score 1) 202

This seems to be an incredible invention that will be a game changer. Passive cooling on the order of what this article talks about would seem to be too good to be true. If it is true these guys should be filthy rich soon.

Well the article certainly lacks critical sense:

And because it can be made cheaply at high volumes, it could be used to passively cool buildings and electronics such as solar cells, which work more efficiently at lower temperatures.

Cool solar cells.... by blocking the sunlight *facepalm*. Also I'm thinking how big a deal is the "not blocked by the atmosphere" really, I mean it's not like heat reflected of a little building significantly changes the ambient temperature. And finally production cost is one thing, but how it works in real dust-covered conditions and if it can survive being exposed to the weather all year long is another matter. I don't think it's quite as revolutionary as the article might suggest.

Comment Re:Not really a success for the AI (Score 1) 76

No, this is like a self-driving car that only works in GTA because it has a pipe into the hard data for locations of obstacles and other vehicles etc.

Wouldn't that still mean you've reduced an AI problem into a computer vision/identification problem? Like making a video recording of a chess board and saying if we could identify where the pieces are, we'd know what to play. I imagine the computer could look at the framebuffer and "derender" the picture back into game state a lot faster than a human, then feed that into the same algorithm. Would that really be meaningfully different?

Comment Re:They did it to themselves (Score 5, Insightful) 259

When you make HUGE price tags to repair items, people are going to repair it themselves. I previously worked for Lenovo/Asus repair depot. To replace an LCD was over $300. Part on eBay is about$60 takes maybe 10 mins depending on the model. So when you flease the customer long enough, they attempt it themselves because the $300+tax or buy a new one for $400. Most think I'll give it a shot for $50.

I think the biggest issue for any repair shop is they can't deliver "I'll give it a shot" service. If it doesn't work, people aren't very likely to pay you $50 or even believe you really tried at all. If it turns out something else is broken too, they won't be very happy being stuck with a bill and a still broken machine. In fact you could end up in an argument about what was broke or if you broke it. If you do it yourself as a last-ditch attempt before throwing it in the trash you got nothing to lose, but deliver it to a repair shop and the customer will never accept that. They want a quote and a repaired machine for that price and you're burdened with the risk of delivering that. If those parts on eBay turns out to be faulty or shoddy knock-offs that don't quite work right or have quality issues that could become your problem too. Also if bad shit happens shortly after it comes from your shop they'll try to blame it on your repair, whether it's actually correct or not.

All of this starts amounting to quite a bit of overhead, if someone comes in with a machine you probably can't make an off the cuff estimate. First you have to figure out roughly what's wrong, what parts costs, the time you'll spend and the risk you're taking then give a quote based on that. And very often the customer will say it's not worth it and go buy a new machine and that time is lost. And then you'll have customers who want time estimates or worse yet guarantees and you have supply chain issues you'll spend time dealing with customer complains and they might haggle or cancel their business and you might get stuck with the bill. And you will have all the ordinary business overhead of having a shop, maintaining an inventory and billing system, taxes etc. and people that don't ever come to collect or pay. And if you're shipping you will spent time wrapping and unwrapping, collecting and delivering, dealing with transport damage etc.

I have some friends that are in the construction industry, they say pretty much the same. If you take away all the overhead, preparation and cleanup and just look at the time the handyman actually does this craft the hourly rate looks bizarre. But after dealing with "everything else" it's not like they walk away with that much per hour worked. It's the cost of doing it as a business, if they were just working on their own house they could do it way, way cheaper. It's simply a matter of trust and risk management, like I rented an apartment from an ex-classmate some years ago. Even though we weren't exactly friends he'd much rather rent to me than to some stranger, simply because he knew I'd be a no fuss tenant. The money is in easy business, dealing with complex and unique situations lie half-broken machines is often unreasonably time consuming and thus expensive. Getting a "known good" one off the assembly line often wins on simplicity.

Comment Re:Not a problem at all (Score 2) 1105

There are dicks everywhere. People of all religions, ethnicities, colors, and even financial backgrounds don't like and/or trust other people who are not like them.

Well yes, but using extremes can often lead to a sort of moral relativism where everybody is equally bad even though one is a fringe movement and the other a mainstream sentiment. I'm sure there were a few black supremacists, but nothing like the KKK. I'm sure some Jews hated the Nazis, but nothing like the Holocaust. I don't know if it's been listed as a fallacy but the appeal to indifference certainly should be, like they were probably just as bad as us. No, they probably weren't.

Comment Re:Not really a success for the AI (Score 5, Insightful) 76

No, the purpose of AI should be that it can problem solve and adapt to a situation as well, or better than us. With an unfair reaction benefit it can actually problem solve worse, yet still win simply because it has an external advantage. That doesn't sound like a win for AI to me.

If a self-driving car can drive better than you because it's got 360 degree vision, millisecond reaction time and the capacity to focus on ten different factors at once is that "cheating"? I think that's a matter of perspective, limiting it to the wheel's turning rate and the pedals' actuation force sounds like unreasonably hampering the performance. Maybe that's not a "fair" fight, but I'd say we probably want the computer to play to its strengths and not mimic our weaknesses.

Comment Re:git was written when SHA-1 attacks were publish (Score 1) 197

If you think that SHA-3 somehow magically makes everything more secure for verifying data have not been modified in transit (e.g., installer gets corrupted while being downloaded) because you replaced all the SHA-2 hashes with SHA-3 hashes on the installer download page which is served over insecure HTTP, then I suspect you may not fully understand what threats you are trying to protect against.

The point is that if you're trying to use a hash instead of a checksum, it'll actually work as advertised. If you only care about random bit flips CRC32 will work very well and be much faster than MD5 or SHA-1. If you're doing major overkill you might not care that a hash doesn't function as a hash because you don't actually need a hash but that's no reason to use a bad hash. You should either use a good hash or use a lesser solution that doesn't pretend to make promises it can't hold.

Comment Re:And you should learn to read before replying. (Score 1) 150

The postal workers, who ship mail for a living, really should have advised him better.

That's like saying the people taking orders at McDonald's make food for a living. While there's of course exceptions I generally assume retail clerks don't have any real experience with any other part of the business than pointing out where things are, pushing the products and accessories the company wants to sell and working the cash register. The real skilled people are often working somewhere else, the front line staff is often temps and extras or quite happy with jobs where they don't have to think so hard. Not that I really blame them, but I'd rather set my expectations low and be positively surprised instead of the other way around.

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"It ain't so much the things we don't know that get us in trouble. It's the things we know that ain't so." -- Artemus Ward aka Charles Farrar Brown