Yeah, I'd be more concerned about the "over the air" updates.

If he wanted you dead, all he has to do is push an update that tells the car to not brake or tell the suspension to slam you into the ground.. or to overdraw the batteries causing a fire.. or take over the steering and slam you into a wall. Or discharge all the airbags while you're traveling highway speeds... you get the idea.

I wonder what kind of security that communication system has.

Dumb it down for me.. how many library of congresses is 2 pints?

I never meant to imply that sorting a list is a hard problem to parallelize. I was just demonstrating that some problems will introduce overhead for interprocess/inter-thread communication.

A better example might be simulating heat transfer inside of an oven with some stuff inside. You can divide up the volume of space into N equal chunks, but at each iteration the processes must communicate their boundaries to neighbouring chunks. The smaller you make the chunks (ie the more processes) then the more of this boundary condition communications that are necessary and it eats into your speed up.

Hrm... how many oxen could you buy for the price of 1024 chickens?

I'd love to redline a ferrari to get the groceries, but where do I put the child seat?

Parallelization does introduce it's own overhead. Some problems can be made to run parallel very easily without much effort. For example, lets say you have an unordered database of names and you want to count how many letter "A"s are in each name. You can very easily divide the database into eight equal parts and send it off to eight cores for processing and they will happily churn away until you have your answer with almost no additional overhead.

However, different problems cant be as easily parallelized. For example, lets say you take the same database of names and you want to sort it alphabetically. You can send each chunk of the database off to be sorted on each core, but now you have 8 pieces of the database that are all sorted and need to be merged back into the original list. This extra work of merging and communicating becomes the overhead.

This is a very simple example, but for many problems the speed gained by parallelization is reduced for every new thread. So you might get an almost 50% speedup by adding a second core, but the third core will give you maybe only 20% speedup, and the fourth 15%, etc...

And as mentioned by others, parallelization is almost always done to improve performance, not efficiency. It would be more power efficient for the one core to do the job if you are measuring efficiency by something like cycles per watt. This doesnt make much sense in a mobile device whose paramount concern is to run a long time on a battery.

I've just got my 3D printer working quite well. I bought a kit second hand from someone who didn't have time to finish it and after building my own electronics and writing my own firmware for it, I'm probably in to it about $300.

I never really had the intention of printing enough stuff to pay for the printer, but it may still do that. One of the things I'm currently working on printing (printing out a piece a night) is a solder fume extractor. This is a relatively simple tool that sucks solder fumes through a carbon filter and normally costs ~$150 - $300. The one I'm printing should be just as good and will cost maybe $20 including plastic, fan, and filters.

Also, if you want to try and pay off your printer, you could print new printer kits and sell them online or to friends. But, it is ONLY going to "pay" for itself if you don't value your own time, since you will spend a lot of time nitpicking, calibrating, babysitting. Although babysitting isnt as big of a deal, I just try and check on it every half hour to an hour. Many people will even just let stuff print out over night, but I'm not quite at that level of trust just yet. It's not that I care about wasting plastic, but that I don't want to die in a fire while I sleep.

The real advantage to a 3D printer is that you can design and build your own stuff very quickly. If I want to design and build a small robot, I can draw up some wheels, a frame, some servo mounts, etc.. and have a very nice professional looking toy robot in a couple of days. Or if I want to make a simple enclosure for an electronics project I can import a 3D representation of the circuit board, draw a box around it, cut out holes for switches, connectors, LEDs, and print.

It is also technically possible to generate fuels from captured atmospheric carbon and water. Although this takes vast amounts of energy that is currently unavailable and uneconomical. Although, it will likely remain uneconomical so long as we can continue to pump energy out of the ground.

As someone who enjoys tinkering with the hardware, it would be even cooler to have one team develop the robot hardware and the other develop the software. The software should be designed such that it can easily be ported to a new robot platform using the same inputs/outputs.

They are likely doing both. The full body scanners and X-Ray machines are probably meant to detect these types of non-metal weapons.
It does make sense though that they ask legitimate manufacturers to include a metal slug since it doesn't harm legal users and could increase the detection of illegal users.

Well, I could see it being a problem simply because they are plastic. Think of all of the places where you have to pass through metal detectors for security. This "gun" will not set off a detector (unless the maker was kind enough to include the chunk of metal designed to set off detectors).

Desperate people may not care that the gun isn't very safe or usable; all it takes is one bullet to assassinate someone, one bullet to kill somebody in a prison, one bullet to hijack a plane (maybe not quite doable on a plane, but maybe with more than one person with these plastic weaposn?). It also would make an excellent untraceable murder weapon. Build gun which just has to fire one round, do your business, and then toss the gun into a fire where it can be completely destroyed.

Yup.. the more I think about it, the more gimicky and stupid this "invention" seems. They just want people to buy it so that they can say to friends they have a high tech sci-fi gun.

Better yet, why not make it so that there is an iris scanner in the barrel... just point the gun at your eye and it will disable the safety.

I was working under the assumption that once "unlocked", the gun would continue to fire until "locked" again.
Not sure if this is the case, but I would imagine while hunting you would unlock it when you first enter the woods, and lock again when you're leaving for home.

Presumably because people buy guns for security, not just for entertainment at a range.

If you're about to be attacked/killed by a burglar and you reach for your gun and pull the trigger you want to make sure as hell that the gun works. If it doesn't work, for whatever reason, you're in a worse position than you started because now the burglar has reason to incapacitate/kill you.

I cant see this being useful for a security gun. If you reach for your gun you'll have to very consciously "unlock" it with your fingerprint. If your nervous, it's dark, or whatever, it might not recognize you. Even in the best case scenario, this unlocking will take time. Couple that with requiring a battery, and it could be trouble.

However, if this is just being used to secure less crucial weapons such as hunting rifles, or the kind that you might only ever use at a range, I could see the fingerprint being scanner being useful. It would help to prevent children or thieves from using your weapon and when you're hunting or at the range, you presumably have the time to check the batteries and swipe your finger a second time if it fails to register you the first go.

I suppose it is opinion. It just doesn't make any sense to me that our purpose is to have no impact on the universe. Not only my quoted above statement an opinion, it is also ambiguous as there is no great consensus on what it means to "improve" the world and universe. Just because the basis of my argument is an ambiguous opinion doesn't mean that my argument should carry no weight.

In my opinion, an engineered reef is better than a dead one. So it makes sense to try provided that we can have some reasonable assurance that any human engineered reef isnt going take over the entire ocean or squeeze out native reefs (or other species for that matter). This is not a trivial problem, but I don't think its worth abandoning all-together simply because anything we make is not "natural".