Slashdot Mirror

This refers to more primary scholastic algebra of course. It is not the same as linear algebra but in basic ways that earliest form is closer to algebra.

The imagery looks like the actual measurements are LiDAR derived.
Similar levels of accuracy are available from the GPS system when differential GPS is used. More information about GPS here:
Continuously Operating Reference Station (CORS) http://geodesy.noaa.gov/CORS/

It is rocket science, however today not surprising. The really hard part of this is that the data is available in near real time. See the Sentinel mission website
https://sentinel.esa.int/web/sentinel/missions.

Any time a building incurs settlement like this I wounder if the foundation layer - likely some sort of clay - is a thixotropic material potentially subject to liquefaction when shaken. Reference Jan. 17, 1995 Hyogo-Ken Nanbu Earthquake:Technical Paper on Liquifaction and,Earthquake Impact on Kobe

I wonder if they teach that in those call centers in India, or those single programming courses companies make people take when they're trying to cut out the cost of programmers altogether.

Yes, they do. Not in call centers though, but in Universities across India. If your purpose was to slander Indian education system or belittle the coders there - then that's a FAIL. The guys there are as good [or bad] as they are over here. The spread is larger because of the bigger population.

In the case of Cherekov radiation the particles aren't traveling faster than C. The single particles phase velocity is traveling faster than the group velocity of the rest of the light. This causes the blue glow which is similar to an object breaking the sound barrier. But group velocity never exceeded C. Remember, light can slow down too.

As of "now" it is accepted that nothing travels faster than C.

Even this experiment did not conclude that the particle traveled faster than light. Only that the shift in quantum state of the observing electron happened before the particle entered the chamber. There's still no proof that the particle itself exceeded the speed of C.

>Like geostationary satellites.
One lucky break does not mean all his 'predictions' are legitimate. Mr Paedophile also said that , by now, we'd have cities on Mars. Do we? Will we ever? Not likely now that the USSR is gone and nobody cares about space travel anymore. Clarke was a chap who rode with the trends and fads of his generations, nothing more.

>This dispute smells of a engineer v/s theoretician catfight.

Sorry, but that won't wash.I'm an IIT alumnus, so my training background has a fair amount of engineering in it. I"ve taken core and ESO-BSO courses with engineering students. I am, in fact, very engineer-friendly. Just not NASA engineers. NASA is a political organization, not a scientific one.

Critics have raised concerns that the decision to go with the the rickshaw-powered design will deprive the citizens of Indonesia from reaping the full benefits of the internet. The openness of the rickshaw platform prevents users from achieving the level of privacy that is typically required to enjoy some of the more popular internet prOn sites.

For more information about the rickshaw powered design, you can check here :
http://www.iitk.ac.in/MLAsia/infothela.htm

I have found a bug (probably). Does any body know where to report it? I am unable to find such a place on mozilla site.

Btw, here are the screenshots of the problem: problem in scrolling down: 1 2

I have found a bug (probably). Does any body know where to report it? I am unable to find such a place on mozilla site.

Btw, here are the screenshots of the problem: problem in scrolling down: 1 2

Shown by Manindra Agrawal et al in 2002. They have a site with info.

Most probably, they have reinvented faster than light communication, but they daren't claim it.

No sarcasm intended, merely meant it as a compliment. Noticed that the upper directory had a lot of other cool math stuff, too.

(haven't gone through them - yet, merely noticed that there seemed to be a lot of good mathematical content).

You should probably read Primes is in P - good paper.

PS - There is no such thing as FBT, atleast AFAIK. Is that one of yours? Has it been published/peer reviewed?

It is considered likely by many that a polytime algorithm for deciding instances of NP-complete problems would also provide efficient keyspace search for cryptanalysis. This is a consequence of the "polytime thesis" (sorry about the crufty link, but I didn't spot anything better offhand: look way down near the end), which states that any real-world problem that has a polytime algorithm has a feasible algorithm. Note that this is both fuzzy and a thesis rather than a theorem, but I am not aware of any counter-examples. So, based on empirical evidence of past discoveries, we might well expect that if we can find a polytime algorithm for keyspace search, we can also find a feasible algorithm.

Consider the problem of deciding whether a number is prime. This problem was recently shown to be in P, but the algorithm given requires around |n|**12 steps in practice. Obviously, this is still not a feasible algorithm. Proponents of the polytime thesis, however, are not concerned: they believe that a low-order polytime algorithm will soon be found. I tend to agree with them.

The primality problem, closely related to most public-key algorithms,(since we have to decompose a big composite in two big primes),it is not even a NP problem.

Ah yes, my bad. Thanks for pointing it out! :)

I've even read a paper on this, called Primes is in P.

Agreed that the terrain is not as demanding as in Nepal (flat plains vs. extremely hilly), but the goals look similar. They also have a pretty Coverage Map

The ranges they get out of wifi links are also pretty good - 5kms is on ordinary antennas, while with properly aimed parabolic antennae (antennas?) they get upto 40 kms (25 miles)

Agreed that the terrain is not as demanding as in Nepal (flat plains vs. extremely hilly), but the goals look similar. They also have a pretty Coverage Map

The ranges they get out of wifi links are also pretty good - 5kms is on ordinary antennas, while with properly aimed parabolic antennae (antennas?) they get upto 40 kms (25 miles)

The IIT Kharagpur is giving practical lessons in electronics and robotics to the childrens residing in the villages in India. These robots are very simplistic in nature and may not be so "high-tech" but is empowering the Indian Kids and finding the "real world" application and not mere fun or educational project.The program is called Build Robots Create Science BRiCS

Prof. Manindra Agarwal and two of his students, Nitin Saxena and Neeraj Kayal (both BTech from CSE/IITK who have just joined as Ph.D. students), have discovered a polynomial time deterministic algorithm to test if an input number is prime or not. Lots of people over (literally!) centuries have been looking for a polynomial time test for primality, and this result is a major breakthrough, likened by some to the P-time solution to Linear Programming announced in the 70s.

You may want to add this one to your list....

Primes is in P

While it *is* impressive that these people are doing this over 36 miles (56 kms) from non-commercial equipment, IIT Kanpur has already done this over 40 kms (25 miles) using ordinarily available parabolic antennae (no Pringles available ;)

And, IIRC, there was a project a while back to do the same over 72 miles (which also succeeded)

I would argue that the entrant to any of the IIT's is TECHNICALLY much more qualified than 99% of the entrants I've seen in the US. To get into the IIT's, you need to clear what is known as the Joint Entrance Examination (JEE). The examination is conducted all over India. An estimated 250000 students take the exam yearly with about an estimated 2500 getting through to the 6 campuses of IIT's. The entrance exam is grilling. It encompasses three 3-hr exams in maths, physics and chemistry. The syllabus of these exams is roughly equivalent to that of a 3-year bachelor course in science (BSc). So its like you need to be about 3 years ahead of your grade to get through. With the increasing number of applicants, the exam has been made into a two stage exam - a three hr screening multiple choice exam followed by the aforementioned three 3-hr exams. You have to clear both!! Typically students start preparing for the JEE exams atleast 2 years before they give it. School work is neglected as the syllabus for the JEE is way more advanced than the normal school. The JEE is not a joke. It is one of the toughest exams to get through. Take this as an example - two senior year students came up witha polynomial time algorithm for Primality testing.

Obviously I'm really into the whole situation of IT in Africa (they call it ICT .. the C is for communications). Here are some links for you to look at. A lot of them are really oriented towards WiFi too since I think that's the "last best hope" for the internet in Africa

Weblogs:
riptari filter

m u l t i p l i c i t y

R Alden

News

Balancing Act: Africa This looks dense but it's the BEST news source about ICT in africa and getting better all the time. Very reliable too.

Shameless plug
I wrote about using the open source model for (ICT) development here and some other stuff from here.

Stories

Laos

You've already heard about that ... but this much more story and pictures about another project:

Pictures, stories, of setting up the real thing in Bhutan a country you've maybe never even heard of ... but they have a WiFi based VoIP long-distance system that doesn't even need electrical grid to work.

I'll leave you with one that's going on right now ... the Digital Plains of India.

simon

Mathematicians described the advance -- announced at a conference in Germany -- as the most important breakthrough in the field in decades.

Personally, I think the technique for provably determining the primality of an arbitrary number in polynomial time -- "PRIMES is in P" -- was a more unexpected result. It's always seemed like the probability of a twin prime occuring on the number continuum was a limit approaching but never quite reaching 0 -- an artifact of the number of previous primes already "exposed" approaching, but never reaching infinity. But actually sitting down and proving this -- excellent! Very cool.

--Dan

How do you think the recent discovery of a formulaic test for the primality of a number might affect current cryptographic systems? Is there a way to exploit this method into a better system for factoring large primes?

I "sniff" two main arguments out of this article:

1. is that java is not reliable: eg: inherently unstable (understandable b/c its a complex problem), AND this memo exposes some of the design issues over the progressing releases of java (which they actually classify as bugs (not in runtime or anythiing, but in usability and maintainability).

2. is the performance aspect that they are whining about. (both timewise, and memorywise).

Well....for the amount of garbage collection and optimization that goes on in a JRE (like the HotSpot (tm) and what not...)its not wonder that its "big". Sheesh, it took 30 years to figure out primes in P http://www.cse.iitk.ac.in/news/primality.html , and what? its been less than 10 years since gosling has managed to convince sun that java is worth it.
Anyway, theres a reason python and eiffel are more stable...they do less optimization. Please don't argue that python is anywhere near as fast as java. The computer language shootout, OR just experience with both languages can tell you this.

Anyway, I think that ultimately, computers should have something like a co-processor for bytecoded languages. Everyone needs to get together (like the now-dying parrot project), make a SOLID standard for a bytecode and for a hardware implementation, and sit back and enjoy the ride (eg http://www.ajile.com/ ...but based on something less proprietary). Heck we have graphics cards dont we!

Finally,if sun is bailing, im sure a CS department/thinktank will pick up a grant and continue with java in a completely non-proprietary fashion (java *is* open source, just too proprietary to conflict with GNU and what not... (not like im a gnuru or anything).

Im sure theres something im forgetting. thank ya.

apparently it's been moved:
http://www.cse.iitk.ac.in/news/primality.ps

the ps version looks much better:
http://www.cse.iitk.ac.in/primality.ps

We had our own computer centre (for non CS students) at IIT Kanpur since a long-long time. They run mostly NFS with HP-UX an Solaris servers. It's really cool to have 24-hour on-campus access to a place running Linux isnt it ;-) ? IMHO , public access linux centres help to create more *nix awareness in the community, and aid tremendously in open source development by non-CS hackers.

We had our own computer centre (for non CS students) at IIT Kanpur since a long-long time. They run mostly NFS with HP-UX an Solaris servers. It's really cool to have 24-hour on-campus access to a place running Linux isnt it ;-) ? IMHO , public access linux centres help to create more *nix awareness in the community, and aid tremendously in open source development by non-CS hackers.