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The Future of Optical Fibre

An anonymous reader writes "An Australian researcher has come up with a novel way of developing optical fibres. Steven Manos, a researcher at the Optical Fibre Technology Centre in Sydney, Australia has developed a method of using genetic algorithims for discovering optimal designs of optical fibres. An article on his work had this to say "The problem with designing optical fibres is starting with a specific set of criteria and then coming up with a design to fit this. The computer program developed by Manos, which is run on supercomputers, does this by mimicking the process of evolution. The computer program combines two patterns to create a third fibre 'offspring', which Manos described as "similar but a bit different". This process is repeated thousands of times with the 10 designs best suited for the particular application chosen to 'breed' again." Another case of "When in doubt, use brute force"?"

13 of 139 comments (clear)

  1. Brute force? Not exactly by haluness · · Score: 5, Insightful

    I'd rather not think of the method as brute force. Ok, its not like a design from first principles, but its still way to search the parameter space without having to test all coimbinations of parameters

    1. Re:Brute force? Not exactly by neilmoore67 · · Score: 5, Insightful

      I'd rather not think of the method as brute force.

      Well said. Brute force would be enumerating every possible optical fibre and then testing them.

      This method is more subtle and converges to a close-to-optimal solution with less computer power having to be applied.

      --
      You've probably noticed that people's noses get bigger as they get older. That's because old people are huge liars.
    2. Re:Brute force? Not exactly by N+Monkey · · Score: 4, Insightful

      I'd rather not think of the method as brute force.
      I'll agree with that. Brute force searching would go though all the parameters a la ..

      for(parameter1 = min limit ...)
      for(parameter2 = min limit ...)
      for(parameter3... )
      etc....
      Evaluate(parameter1, param2, ....)

      Genetic algorithms try to limit the search space by starting with "probably good" sets of parameter values and trying to generate other "probably good but hopefully better" parameter combinations.

      It won't necessarily find the absolute best set of parameters but it might find some reasonable ones.

    3. Re:Brute force? Not exactly by Anonymous Coward · · Score: 1, Insightful

      Wrong wrong wrong.

      GA is not guaranteed to converge to a "close-to-optimal solution". With results from a GA you do NOT know the solution is optimal. The **hope** is that by wiggling around somewhat in parallel with your genetic inputs that you have a better chance to find a global optima. That is just a hope.

    4. Re:Brute force? Not exactly by essreenim · · Score: 2, Insightful

      I agree. Brute force on its own is inefficient and predominantly useless.
      Even at tasks it can be applied to - like key cracking etc, it is still practiacally uselless without a bit of intelligence build in.
      Even the best prime generators dont doa brute iteration through all integers > 0 to infinity - that would be pointless. You need to know where to look as well, or your waisting your time.
      I hope as computers continue to advance we dont forget this and simply rely on computing power. Because no matter how far computing powere progresses, we still need to use our own brains with it, not have them replaced alltogether, if we did that we wouldn't get anywhere ...

  2. What the... by eddy · · Score: 2, Insightful

    Another case of "When in doubt, use brute force"?

    Evolutionary search isn't "brute force", you id... At least not for meaningful definitions of 'brute force'

    Brute force would be starting at one end of design space and evaluating each design in turn.

    --
    Belief is the currency of delusion.
  3. GA's are not brute force by jdrugo · · Score: 5, Insightful

    ..as they don't search the state space exhaustively. Going through all possible combinations of parameters would be brute force, but in this case, as the parameters are real-valued, this is even impossible (if ignoring the possibility of quantisation)

    Evolutionary Algorithms provide informed search as they perform competition among the individuals (each representing one possible solution) in the population. Their performance is way above exhaustive search techniques (which _are_ brute force) but below classical search techniques. In this case, however, such classical techniques cannot be applied as the problem space is not well-defined.

  4. No, Taco, No by neoshroom · · Score: 5, Insightful

    Another case of "When in doubt, use brute force"?"

    No, Taco, No.

    From the 'brute force' entry in Wikipedia:

    In computer science, Brute Force, sometimes called the Naive Method, is a term used to refer to the simplest, most intuitive, most spontaneous, and usually most inefficient methods of accomplishing a task.

    This is exactly what a genetic algorhthem is not. If you have a million numbers brute force would be to go from the first to the last in order. Using a genetic algorhythem provides a shortcut though Design Space wherein you need to try far fewer combinations in order to come to a successful result.

    C'mon Taco, of all people, you should know this!

    --
    Big apple, new Yorik, undig it, something's unrotting in Edenmark.
  5. Re:Brute force breeding by Anonymous Coward · · Score: 0, Insightful

    You may be trolling, but I'll point it out anyway: evolution doesn't have an end point. It is a path - a path with many branches and dead-ends - and not a destination. And I'm not being all metaphysical and hippy-ish about it.

  6. this guy is way too confident by kjba · · Score: 3, Insightful
    No other algorithm can come up with a design for optical fibres that are cheap to make and transmit data at a high rate, Manos said.

    How can anyone make a claim like this? Just the fact that one can't think of any other algorithm doesn't mean no such algorithm exists. For many problems that can be solved by genetic algorithms, other (problem-specific) algorithms exists (or may exists) that are way more efficient. The nice thing about genetic algorithms is that it is a standard tool that often works, not that it is an exceptionally smart way of doing things.

    1. Re:this guy is way too confident by geeber · · Score: 4, Insightful

      Well, actually lot's of algorithms exist for designing optical fiber, and they do it efficiently and very accurately. I use a number of in house proprietary programs for designing optical fibers all the time. And I can tell you we don't waste time messing around with GA's

      So why don't you hear a great deal about such algorithms? Well, for one, they don't have cool names like "Genetic Algorithms". Also, they are highly prized and considered extremely valuable intellectual property for the companies that actually make optical fiber. We are not going to publicise all the details the most fundamental design tools of our business.

      GA's are not the future of optical fiber. They are, however, excellent for generating academic papers, which in turn are highly useful for getting tenure.

  7. What's so great about meat? by szquirrel · · Score: 3, Insightful

    This process is repeated thousands of times with the 10 designs best suited for the particular application chosen to 'breed' again." Another case of "When in doubt, use brute force"?

    More like another case of computer science being fascinated by meat.

    Remember when neural networks were the next big thing? Everyone was applying them to everything, whether or not it made sense to solve the problem that way. It's neural! Just like our brains! Our brains are smart, they will make our computers smart!

    I'm sure genetic algorithms will eke out a useful place in the computer science toolkit, I just doubt it will be as broad as the current fashion of applying them to everything from optical fiber to race cars to compilers.

    --
    Never approach a vast undertaking with a half-vast plan.
  8. Re:Brute force? No way? by ortholattice · · Score: 2, Insightful
    ...so long as you dont care that... b) Some alternative minima are missed

    The problem of local minima is often significant. A good analogy is real genetics - each species has evolved into a "local minima" for likelihood of extinction. If the wings on a given type of butterfly become slightly larger or smaller there will typically be a survivability penalty of some kind, and wing size has stabilized at the optimum for that species. But look at the difference in possible local minima: in one case it results in a whale, and in another it results in toenail fungus. Neither could survive if suddenly given some of the characteristics of the other. A beautiful orchid is a local minimum, and so is pond slime. Your genetic algorithm could decide that pond slime is the optimal product, and the difference can impact your ornamental plant business due to subjective things like beauty that can't be quantified.