Christopher Ronnewinkel

Learn More
We present a multipopulation concept that detaches global from local search. A search population constantly searches for new regions of high fitness, whereas colonies track already found fitness peaks. The colonies interact via a parameterless speciation criterion. In a performance test on multiple stochastically moving fitness peaks on the hypercube, we(More)
We study self-replicating molecules under externally varying conditions. Changing conditions such as temperature variations and/or alterations in the environment's resource composition lead to both non-constant replication and decay rates of the molecules. In general, therefore, molecular evolution takes place in a dynamic rather than a static fitness(More)
The influence of time-dependent fitnesses on the infinite population dynamics of simple genetic algorithms (without crossover) is analyzed. Based on general arguments, a schematic phase diagram is constructed that allows one to characterize the asymptotic states in dependence on the mutation rate and the time scale of changes. Furthermore, the notion of(More)
The quasispecies theory is studied for dynamic replication landscapes. A meaningful asymptotic quasispecies is defined for periodic time dependencies. The quasispecies' composition is constantly changing over the oscillation period. The error threshold moves towards the position of the time averaged landscape for high oscillation frequencies and follows the(More)
We study the evolution of asexual microorganisms with small mutation rate in fluctuating environments, and develop techniques that allow us to expand the formal solution of the evolution equations to first order in the mutation rate. Our method can be applied to both discrete time and continuous time systems. While the behavior of continuous time systems is(More)
Many real-world optimization problems are non-deterministic and subject to changes over time with respect to the objective function, decision variables, and/or environmental parameters. For dynamic optimization problems, the goal of an optimization algorithm is no longer to find a (stationary) optimal solution, but to continuously track the optimum in the(More)
The quasispecies model is studied for the special case of externally varying replication rates. Most emphasis is laid on periodic time dependencies, but other cases are considered as well. For periodic time dependencies, the behavior of the evolving system can be determined analytically in several limiting cases. With that knowledge, the qualitative phase(More)
  • 1