To boldly go:an occam-π mission to engineer emergence

Future systems will be too complex to design and implement explicitly. Instead, we will have to learn to engineer complex behaviours indirectly: through the discovery and application of local rules of behaviour, applied to simple process components, from which desired behaviours predictably emerge through dynamic interactions between massive numbers of instances. This paper describes a process-oriented architecture for fine-grained concurrent systems that enables experiments with such indirect engineering. Examples are presented showing the differing complex behaviours that can arise from minor (non-linear) adjustments to low-level parameters, the difficulties in suppressing the emergence of unwanted (bad) behaviour, the unexpected relationships between apparently unrelated physical phenomena (shown up by their separate emergence from the same primordial process swamp) and the ability to explore and engineer completely new physics (such as force fields) by their emergence from low-level process interactions whose mechanisms can only be imagined, but not built, at the current time

The resonant structure of Jupiter's trojan asteroids-II. What happens for different configurations of the planetary system

In a previous paper, we have found that the resonance structure of the present Jupiter Trojan swarms could be split up into four different families of resonances. Here, in a first step, we generalize these families in order to describe the resonances occurring in Trojan swarms embedded in a generic planetary system. The location of these families changes under a modification of the fundamental frequencies of the planets and we show how the resonant structure would evolve during a planetary migration. We present a general method, based on the knowledge of the fundamental frequencies of the planets and on those that can be reached by the Trojans, which makes it possible to predict and localize the main events arising in the swarms during migration. In particular, we show how the size and stability of the Trojan swarms are affected by the modification of the frequencies of the planets. Finally, we use this method to study the global dynamics of the Jovian Trojan swarms when Saturn migrates outwards. Besides the two resonances found by Morbidelli et al (2005) which could have led to the capture of the current population just after the crossing of the 2:1 orbital resonance, we also point out several sequences of chaotic events that can influence the Trojan population

Capturing pattern bi-stability dynamics in delay-coupled swarms

Swarms of large numbers of agents appear in many biological and engineering fields. Dynamic bi-stability of co-existing spatio-temporal patterns has been observed in many models of large population swarms. However, many reduced models for analysis, such as mean-field (MF), do not capture the bifurcation structure of bi-stable behavior. Here, we develop a new model for the dynamics of a large population swarm with delayed coupling. The additional physics predicts how individual particle dynamics affects the motion of the entire swarm. Specifically, (1) we correct the center of mass propulsion physics accounting for the particles velocity distribution; (2) we show that the model we develop is able to capture the pattern bi-stability displayed by the full swarm model.Comment: 6 pages 4 figure

Distribution and transmission of American foulbrood in honey bees

The distribution of Paenibacillus larvae spores, the causative agent of American foulbrood, was studied on three different levels in the honey bee system; the apiary level, the colony level and the individual honey bee level. The increased understanding of spore distribution has been used to give recommendations regarding sampling of adult honey bees. The vertical transmission of P. larvae spores through natural swarms has been described for the first time and artificial swarming as a method for control of American foulbrood have been evaluated. The results demonstrated that there is no practical difference in spore load between supers and brood chambers, and that the spore load in samples of adult honey bees on the different levels correspond to the clinical disease status of the colony. The study on individual bees showed that spores are unequally distributed among the bees and that as more bees get contaminated each positive bee also contains more spores. This may present a problem when sampling from colonies with low levels of clinical disease, although the study on colony and apiary level showed no false negatives. A model for calculating the number of bees that needs to be sampled to detect P. larvae in a composite sample of adult bees, given certain detection levels and proportions of positive honey bees in the sample, was developed The swarm study demonstrated vertical transmission of P. larvae spores. Furthermore, the artificial swarm study showed that single and double shaking are equally effective treatment methods, and that the original disease status is of little importance for the spore load decrease