Become a fan of Slashdot on Facebook


Forgot your password?
Check out the new SourceForge HTML5 internet speed test! No Flash necessary and runs on all devices. ×

Sorting Algorithm Breaks Giga-Sort Barrier, With GPUs 187

An anonymous reader writes "Researchers at the University of Virginia have recently open sourced an algorithm capable of sorting at a rate of one billion (integer) keys per second using a GPU. Although GPUs are often assumed to be poorly suited for algorithms like sorting, their results are several times faster than the best known CPU-based sorting implementations."

First Self-Replicating Creature Spawned In Conway's Game of Life 241

Calopteryx writes "New Scientist has a story on a self-replicating entity which inhabits the mathematical universe known as the Game of Life. 'Dubbed Gemini, [Andrew Wade's] creature is made of two sets of identical structures, which sit at either end of the instruction tape. Each is a fraction of the size of the tape's length but, made up of two constructor arms and one "destructor," play a key role. Gemini's initial state contains three of these structures, plus a fourth that is incomplete. As the simulation progresses the incomplete structure begins to grow, while the structure at the start of the tape is demolished. The original Gemini continues to disassemble as the new one emerges, until after nearly 34 million generations, new life is born.'"
The Military

Scientists Turn T-Shirts Into Body Armor 213

separsons writes "Scientists at the University of South Carolina recently transformed ordinary T-shirts into bulletproof armor. By splicing cotton with boron, the third hardest material on the planet, scientists created a shirt that was super elastic but also strong enough to deflect bullets. Xiaodong Li, lead researcher on the project, says the same tech may eventually be used to create lightweight, fuel-efficient cars and aircrafts."

Comment Re:This is BAD BAD BAD (Score 1) 226

I'm not deaf but I think that there is enough a community for deaf people that they have a cultural identity of being deaf. By implanting children with the device, they are no longer in that culture, but neither are they a "normal" fully hearing person, even when they have the device plugged in. This may actually lead to a lower self-esteem for the child than if they were surrounded by people like them (i.e. deaf).

I have a fairly significant hearing loss which caused me a great deal of difficulty when I was at school. My hearing was good enough for me to definitely not be considered deaf, but it often wasn't good enough for me to be able to reliably have conversations with my peers (how well I can hear people varies hugely from very well to not at all).

At the time, I was seriously considering whether I would have preferred to be profoundly deaf for precisely the reasons you outline. Now, my hearing loss is much less of an issue for two reasons: one is that I have better hearing aids, and have had more time to adjust to them, and the other is that I have tuned my life so that I no longer feel any particular desire to socialise, avoiding the problem completely, but at the cost of living a rather more lonely life.

I may, however, just be taking my current level of hearing for granted; I don't know.


Directed Energy Weapon Downs Mosquitos 428

wisebabo writes "Nathan Myhrvol demonstrated at TED a laser, built from parts scrounged from eBay, capable of shooting down not one but 50 to 100 mosquitos a second. The system is 'so precise that it can specify the species, and even the gender, of the mosquito being targeted.' Currently, for the sake of efficiency, it leaves the males alone because only females are bloodsuckers. Best of all the system could cost as little as $50. Maybe that's too expensive for use in preventing malaria in Africa but I'd buy one in a second!" We ran a story about this last year. It looks like the company has added a bit more polish, and burning mosquito footage to their marketing.

Comment Re:Looks interesting as replacement for Python (Score 2, Interesting) 267

The love comes from all the cool things that Python can do, for free. Dynamic typing, .append() functionality, etc. It's just awesome.

You do realize there's no dynamic typing in F#, right? It's very rigidly typed, in fact, more so than C/C#/Java - it won't let you use an int where a float is expected! (it's the price you have to pay for type inference - it doesn't play well with ambiguity)

The hate comes from the sheer lunacy that is Python syntax. Forced whitespacing doesn't suit my debugging style

F# is indentation-driven by default, much like Python (actually, more like Haskell, with more subtle rules). You can turn that off, technically, and use explicit semicolons - but that is considered legacy mode, and the community at large shuns it.

functions names like len() are just, frankly, idiotic (length() is much more readable to beginners, and takes only a few extra milliseconds to type for experienced users)

FP languages traditionally have terse names - how about the classic foldl and foldr ("fold left" and "fold right")? F# mostly follows suite - the most recent version is a tad more verbose, but you'll still be dealing with things such as Seq.mapi.

Although to be honest, I'd love to find a python front end that uses non-insane syntax and then simply precompiles it into python syntax at run-time.

On the whole, it looks like what you're looking for is actually called Ruby.

Comment Re:The optimal blend... (Score 2, Insightful) 267

So why do we have so many unique languages?

It's because we don't have a clear idea on which language features are good, and which aren't. If you ask someone (say, me ~), you'll probably get a straightforward reply, but if you ask another guy, he is quite likely to strongly disagree on many major points.

There are many arguments both for and against dynamic typing, for example. There are similarly many arguments for and against OOP. There are advantages of having code pre-compiled to native, and there are also advantages of having a VM with a JIT compiler. Tracing GC vs manual memory management (+ smart pointers). The list goes on and on...

Within the static typing camp, there are still unsolved issues with the expressivity of type systems - some believe that typeclasses (Haskell-style) are the way to go, but there are still some unresolved problems there for more complex things. Some want effect typing. Some decry both as overcomplicated, and say that they're overkill, and it's easier to simplify the code.

Then there are bleeding-edge language features. Do we need STM? Do we even want it - can it be efficiently implemented at all?

Consequently, you get different languages, depending on which of the above (and many other) points are emphasized. Lately, we're starting to get more "kitchen sink" languages combining all approaches in hope that all of them are useful to one extent or another. F# is actually such a language, in a sense, being hybrid FP/OO (it also has "duck typing" member access, though no means to define true dynamic classes as in Python or Ruby). Scala is even more so.

Existing languages are also heading in the same direction - C# is a good example of that, starting its life as Java-like OO language, then getting some FP features in 2.0, a major FP'esque facelift in 3.0, and now duck typing in the upcoming 4.0.

By the way, F# isn't really a new language. The base language is ML, which is over 30 years old now. The specific ML dialect from which F# is derived is OCaml - that one is still in active development, but got started 14 years ago.

Comment Re:Let 'em sink... (Score 1) 265

We go over there to give them aid, and they get mad because we weren't there sooner. When we actually are there, they shoot at us and steal our things.

Obviously you're grossly over-generalising, etc, etc. But more to the point, this is predictable, and it's not their faults. If you dine in front of a starving person, expect them to get angry. If you go on a spending spree in front of a homeless person, expect them to get pissed.

I don't know enough about the incident in question to respond directly to it, but I'm responding to your comment in general. They ("they" referring to the people in Haiti who have been affected by the disaster) do not have perfect information (they don't know whether the rest of the world is helping, or whether we're too busy with our trivial lives (which, incidentally, for the most part, we are)). If they see some folk who look like tourists, surrounded by life's luxuries, cruise by in a van, they're going to get angry. Sure, it'd be nice if they approached the situation more logically---maybe querying the tourists as to their purpose there---but in their situation, I'm betting emotions are going to come first.

Despite the fact that I strongly disagreed with her previous post, girlintraining made a good point about helping a drowning person. They're likely to cling to you, probably endangering you both. But that _doesn't_ mean you shouldn't help them, and that _doesn't_ make them a bad person. It's an understandable and predictable response. It means you should factor it in when trying to help them. If you want to help a lion with a thorn in its paw, don't be surprised if it tries to eat you first.

Comment Re:Try to give them help and this is what they get (Score 1) 265

If there's no law enforcement left, just how are the emergency supplies that are moving all to slowly going to wind up in the right hands?

The "right hands"? That's rather arrogant of you.

No, it's not. The emergency supplies should be distributed as evenly as possible, with bias in favour of those who need it most. If you're in the sort of situation that people in Haiti are in, and you see a van full of everything you need to survive, you're quite possibly going to do whatever you need to do to get at it (as you yourself mention). Allowing this to happen is _not_ in the best interest of the population as a whole. Don't get me wrong, I'm not in the slightest blaming, judging or harbouring negative thoughts against these people---quite the opposite. But what I am saying is that to help them requires proper organisation, and not recklessly sparking a riot, during which supplies will be wasted, and distributed to only a fraction of the number of people which could be allowed to benefit from them.

Notice that just because I am writing this in the comfort of my armchair does not make it any less true. If I were in their position, I would probably do the same. If you read this as anything even resembling an attack on the people in question, then you read this wrong (or I explained it wrong, or whatever).


Radio Hams Fired Upon In Haiti 265

Bruce Perens writes "A team of radio ham volunteers from the Dominican Republic visited Port-au-Prince to install VHF repeaters, only to be fired upon as they left the Dominican embassy. Two non-ham members of the party were hit, one severely. ARRL is sending equipment, and there is confusion as unfamiliar operators in government agencies join in on ham frequencies."

Comment Re:Netherlands (Score 1) 494

it will be stolen someday. (~750.000 stolen bikes per year, on 15 million people).

My understanding is that most of these bikes have built-in locks which go around the back wheel. These are extremely convenient, but provide almost no real security. Thus, your statistics probably don't apply to people who use a decent lock. So, if you want to ride an expensive bike in the Netherlands, use a decent lock.


The Year of the E-Bicycle 494

theodp writes "Electric bicycles have been around for more than a century, but they have never quite captured the imagination of auto-obsessed Americans. That may be about to change. At CES this month, Sanyo showed off its sleek, lightweight Eneloop Hybrid Bicycle. Priced at $2,300, the e-bike sports a black lithium-ion battery strapped to the frame beneath the seat. Press a button on the left handlebar, and a 250-watt motor kicks in, providing about twice as much power as your own pedaling. Some basic e-bike models, like the Ezip Trailz can be had for as low as $500. Both Trek and Schwinn began selling e-bikes last year, and Best Buy is offering e-bikes in three test markets: Los Angeles, San Francisco, and Portland, OR."

The Weird Science of Tossing Stones Into a Lake 89

Interoperable writes "Researchers in Spain and the Netherlands add another piece to a centuries-old puzzle in physics: the dynamics of an object falling into water. This common occurrence has a complex anatomy that includes a thin 'crown splash' around the perimeter of the impact, a deep cavity of air following the impactor, and a high, narrow jet of water that results from the collapse of the cavity. The new research, recently published in Physical Review Letters, demonstrates that airflow through the neck of the collapsing cavity reaches supersonic speeds despite low relative pressures between the air in the cavity and ambient pressure. Such an effect has no analogue in aerospace engineering or other sciences because of the highly dynamic nature of the collapsing nozzle structure." It's funny that the APS wants to charge non-subscribers $25 to download what is available for free on the arXiv.

Nano-Scale Robot Arm Moves Atoms With 100% Accuracy 266

destinyland writes "A New York professor has built a two-armed nanorobotic device with the ability to place specific atoms and molecules where scientists want them. The nano-scopic device is just 150 x 50 x 8 nanometers in size — over a million could fit inside a single red blood cell. But because of its size, it's able to build nanoscale structures and machines — including a nanoscale walking biped and even sequence-dependent molecular switch arrays!"

Slashdot Top Deals

System checkpoint complete.