演讲人: Freek van Walderveen

讲座时间: 12月4日 下午14:30-15:30

讲座地点: 信息楼417

讲座内容: Title: Handling Massive Terrain Data Subtitle: Using topological structure to design efficient terrain algorithms and data structures Abstract Many interesting problems related to digital terrain elevation models can be solved by first understanding their topological nature. The topological structure of terrains can be expressed as, for example, a contour tree capturing how contour lines drawn at different heights nest inside each other. This tree turns out to have important applications in for example simplifying terrain data (e.g. removing small depressions), and constructing maps of flood risk from extreme rain events.The basic mathematical concepts in this area have been known for some time, but existing algorithms would not work on the extremely large amounts of data in modern, highly detailed digital elevation models. Biography Freek van Walderveen is a research scientist at Scalable Algorithmics (SCALGO) in Denmark. SCALGO is a spin-off of the Massive DataAlgorithmics centre (MADALGO) of Aarhus University in Denmark, and aims at bringing cutting-edge massive terrain data-processingtechnology to market. Freek obtained his PhD degree from MADALGO / Aarhus University, and his masters degree in Computer Science and Engineering fromEindhoven University of Technology in the Netherlands. Freek is broadly interested in the general area of algorithms and computational geometry, as well as algorithm engineering. He has workedon both theoretical algorithm design (e.g. graph algorithms in external memory) and implementation of e.g. external-memory algorithms andhigh-performance architectures for serving hydrological analysis data on the web (seescalgo.com/live).