Shy nag: Second Staging, Bergen 2015

Systems Education at Bergen

At the University of Bergen in Norway, educating students to use computer models and to think systemically about social and economic problems began in the 1970s. The International Masters Program in System Dynamics was established in 1995, and a Ph.D. program began a few years later. Student enrolment doubled in 2010 with the establishment of the European Master Program in System Dynamics. Inte...

Once bitten, twice shy.

B : Multivariable Calculus , Second Quarter , Winter 2015

The Second Reactive Synthesis Competition (SYNTCOMP 2015)

ion Refinement for Synthesis The idea of the abstraction-refinement algorithm is that, given an abstraction, we classify states into one of three categories: winning, losing, and unknown. If we discover that the entire initial set is winning, we know that the original game is winning and we can terminate. Dually, if we discover any initial state that is losing, we know that the entire initial s...

Network Timing and the 2015 Leap Second

Using a testbed with reference timestamping, we collected timing data from public Stratum-1 NTP servers during the leap second event of end-June 2015. We found a wide variety of anomalous serverside behaviors, both at the NTP protocol level and in the server clocks themselves, which can last days or even weeks after the event. Out of 176 servers, only 61% had no erroneous behavior related to th...