Welcome to ACM SIGMOD Record's series of interviews with distinguished members of the database community. I'm Marianne Winslett, and today I have here with me Viktor Leis who won the 2018 ACM SIGMOD Jim Gray Dissertation Award for his thesis entitled Query Processing and Optimization in Modern Database Systems. Viktor is now at the University of University of Erlangen-Nuremberg and his Ph.D. is from the Technical University of Munich, where he worked with Thomas Neumann and Alfons Kemper. So, Viktor, welcome.
This paper presents some aspects of walking machine design with a special emphasis on the three machines MAX, MORITZ and JOHNNIE, having been developed at the Technical University of Munich within the last 20 years. The design of such machines is discussed as an iterative process improving the layout with every iteration. The control concepts are event-driven and follow logical rules, which have largely been transferred from neurobiological findings. At least for the six-legged machine MAX, a nearly perfect autonomy could be achieved, whereas for the biped JOHNNIE, a certain degree of autonomy could be realized by a vision system with appropriate decision algorithms. This vision system was developed by the group of Prof. G. Schmidt, TU-München. A more detailed description of the design and realization is presented for the biped JOHNNIE.
Measurements of the coherent scattering amplitudes of various mixtures of heavy and light water are reported. By means of mirror reflection technique the coherent scattering amplitudes of the D2O and H2O molecule are determined to be 19.148±0.004 F and -1.679±0.004 F, respectively. Use of aH=-3.740±0.003 F, obtained by the same technique, yields aD=6.674±0.006 F as the bound scattering amplitude of the deuterium nucleus. This value disagrees with the widely accepted 6.21±0.04 F, reported by Bartolini et al. in 1968.
Messung der kohärenten Streuamplitude für die Neutron-Deuteron- Wechselwirkung am Neutronenschwerkraftrefraktometer des FRM / Measurement of the n-d Coherent Scattering Amplitude Using the Neutron Gravity Refractometer at the Research Reactor of the Technical University of Munich
