The CS4HS workshop at Sydney will include short talks by some of Australia's leading academics. Each talk will be followed by a practical lab with materials and activities teachers can use in a classroom setting.
These were some of the topics covered in the first Sydney University CS4HS workshop, run in April 2012.
Peter Eades – P, NP, and Complexity
Some computer programs are efficient, some are not. Some problems can be solved by computer, other problems cannot. In this talk we examine what computers can and cannot do.
Sanjay Chawla – The maths of search engines
Everyday we use search engines like Google, Yahoo! and Bing. Often we are still surprised by how these search engines can find highly relevant stuff as if they can “almost read our mind.” I will talk about the underlying mathematics of how search engines rank documents in response to a search query. The mathematics is spectacularly easy (solving simultaneous equations) but is clouded by a scary name: eigen-decomposition of a random walk matrix.
Bernhard Scholz – Parallel Computing
Moore’s law is still intact; the numbers of transistors on a chip is still doubling every two years. However, since 2005 we have observed that the performance of sequential CPUs is stagnating, even though the number of transistors has increased. To overcome this problem, computer architectures have become parallel; instead of having a single CPU, several CPUs are working in concert. Recent simulations have shown that the parallelisation of architectures cannot be increased arbitrarily. Hence, in the future, the only foreseeable way to obtain faster programs is to devise better algorithms.
Masa Takatsura – Information/Knowledge Visualization
This talk will present how Self-Organizing Maps (one of Artificial Neural Networks) help visualising complex information that is typically very difficult understand. In particular, the talk will introduce 1) the benefit of this computional process in improving Analytical Reasoning process, 2) analytic methods using SOM and other visualization/computer vision techniques, 3) examples of knowledge visualisation.
Julian Mestre – Showing off your knowledge without giving it away
Suppose a friend of yours challenges you to solve a puzzle. After working hard on it, you manage solve it. Now you would like to show her that you know the answer, but without giving it away. This seemingly impossible task can actually be accomplished using an interactive protocol, a key concept in cryptography. In this lecture, we will see such a protocol in action for sudoku puzzles.
Michael Charleston – Nothing evolves in isolation.
Parasites and pathogens evolve with their hosts, genes evolve within the organisms that house them, and languages even evolve with people. But there are complications. Parasites and pathogens switch hosts: it's been estimated that about 75% of emergent diseases in humans have come from other species (all the big ones: HIV, malaria, SARS, ebola and so on). Languages die out. Genes duplicate, possibly many times in a single species. Species hybridise. Figuring out what went on in the past between two groups of co-evolving species becomes a computationally very hard problem. In this talk I'll go through some of the ways we've come up with to tackle this fascinating and important problem.