Dirkjan Krijnders is heading the Cognitive Systems Group. His specialization is sound event recognition and classification in open environments. One of his projects is the development of a sensor network for recording and interpreting the sounds of Sensor City Assen. Dirkjan did his Ph.D. at the Auditory Cognition Group of the University of Groningen. He worked on sound source recognition of environmental sounds in arbitrary acoustical circumstances. Dirkjan developed a signal processing technique to reliably extract tones and pulses for audio signals. The title of this thesis was Signal-driven sound processing for uncontrolled environments. Dirkjan earned his master’s degree in Applied Physics from the University of Twente in Enschede. His master’s thesis was on vibrations in stay cables on bridges. The experimental work was done at the Swiss Federal Laboratories for Materials Science and Technology (EMPA).