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Submission + - Arduino Chip-maker Atmel bought by rival Microchip 1

DrJamesSmith @YorkU writes: Microchip, maker of the classic PIC micro controllers, has bought rival Atmel, maker of the processors found on most Arduinos. Microchip beat out Dialog Semiconductor in the process. This follows last year's acquisition of Freescale by NXP. This is an exciting time for change in the maker and microcontroller communities.

Submission + - What's the smallest biggest number you can think of?

serviscope_minor writes: If you think exponentials, factorials or even Ackermann's function grow fast, then you're thinking too small. For truly huge, but well defined, numbers, you need to enter the realm of non computability.

The Busy Beaver function BB(n) is the largest number of steps that an n state Turing machine will run for when fed with a blank tape excluding non halting programs. It grows faster than any computable series but starts off as the rather pedestrian 1, 6, 21, 107. By BB(7) it reaches at least 10^10^10^10^10^7 and at some point becomes non computable. It must be non computable because if it wasn't, you could run a program for BB(N+extra states needed to encode the initial tape state)+1 steps, and if it gets that far then you know it never halts, so you've solved the Halting Problem. So, at some point it must transition from numbers that can be computed to ones that can't be.

And now there's some new and rather interesting insight into that which essentially reduces the problem to code golf or the International Obfuscated Turing Code Contest (as if there is any other sort). Imagine you have an axiomatic system, say ZFC (which underlies almost all of modern maths), and you know you can't prove it's consistent (you can't). If you write a program that systematically evaluates and tests hypothesis based on the axioms, you can't prove it will halt or not since that's equivalent to proving consistency.

This insight and first upper bound is the program proving that BB(7918) is noncomputable comes from this new paper. It turns out that writing a ZFC axiom evaluator directly in a Turing machine is rather tricky and long winded, so the authors wrote a small interpreter for a higher level language then wrote the axiom evaluator in that. Now finding a smaller uncomputably larger number is a question of writing even smaller programs which attempt to compute undecidable things. Think you can do better? A good starting point would probably be the existing code on github.

(I hope I've got the explanation at least half way right!)

Submission + - Apparently Slashdot Mobile Pushed Malvertising Back In January (softpedia.com)

An anonymous reader writes: Crooks used malicious ads (malvertising) to push a fake Android Marshmallow update to Android users accessing a series of high-profile news sites. The malicious ads were found on the mobile versions of reputable sites such as Slashdot and Android Police, but also on local news sites in France (20 Minutes) and Germany (SPON).

This campaign was unique compared to other mobile malvertising waves because it used a never seen before trick which auto-downloaded the fake Android 6.0 upgrade package on the devices without any kind of user interaction.

Submission + - Could the U.S. Navy's unmanned drone warship be hacked at sea?

JustAnotherOldGuy writes: The U.S. Navy and the Defense Advanced Research Projects Agency (DARPA) are now testing a new unmanned drone warship. The drone ship is a 132-foot ACTUV (Antisubmarine warfare Continuous Trail Unmanned Vessel) known as Sea Hunter, which cost around $120 million to build. But some are concerned that with no humans at the controls, these “robot ships” could be hacked, pwned remotely, and used by America's enemies to attack the United States. Military officials have been working on hacker-proof protections and have gone so far as to say that it's possible to make drone ships cyber-secure. Given all of the exploits that appear daily, is this the most optimistic statement you've heard in a while, or should be get ready for hacked drone warships sinking everything in sight? What would Lizard Squad or Anonymous do if they managed to get control of one of these armed drone ships?

Submission + - How Intel Knocked Itself Out Of the Smartphone Chip Market (cio.com)

itwbennett writes: Remember back in 2007 when Intel passed on making chips for the iPhone? In hindsight, that was probably not the best move (Former CEO Paul Otellini admitted as much in a 2013 interview with The Atlantic). But it also wasn't the company's only mistake. The company placed a high priority on the now-declining tablet market. Intel CEO Brian Krzanich, who replaced Otellini, set a goal to ship 40 million tablet chips by the end of 2014 using heavy subsidies on Atom chips. The company shipped 46 million chips that year, but the effort hurt Intel's profitability, and Krzanich decided not to repeat that strategy with smartphones. Late last month the company cancelled its upcoming Atom chip lines for smartphones, including Broxton and the Sofia 3GX, Sofia LTE and Sofia LTE2 commercial platforms. Instead, it's looking for redemption in 5G technology, which won't be limited to mobile devices.

Submission + - Ask slashdot: Clusters on the cheap?

serviscope_minor writes: Dear Slashdotters,

A friend of mine has recently started a research group. As usual with these things, she is on a shoestring budget and has computational demands. The computational task is very parallel (but implementing it on GPUs is an open research problem and not the topic of research), and very CPU bound.

Can slashdotters advise on a practical way of getting really high bang for buck? The budget is about 4000 GBP (excluding VAT/sales tax), though it is likely that the system will be expanded later.

The computers will probably end up running a boring Linux distro and Sun GridEngine to manage batch processing (with home directories shared over NFS?).

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