On May 8 2001, Jaap Seidel passed away. This volume of the European Journal of Combinatorics is dedicated to his memory. Jaap Seidel loved Mathematics. He wanted to learn it, to understand it, and most of all to teach it. In his courses and personal contacts he was very inspiring. Many mathematicians, especially young ones, were influenced by Jaap. Besides being a teacher, he was also very inte...

Analysis of Time Delays in Synchronous and Asynchronous Control Loops Björn Wittenmark, Ben Bastian , and Johan Nilsson email: [email protected], [email protected], and [email protected] Department of Automatic Control, Lund Institute of Technology Box 118, SE-221 00 Lund, Sweden Abstract In this paper we describe how to determine the time delays caused by synchronous and asynchronous co...