First experiences with the H-maser EFOS 1

The results are given on the performance measurements, on the dependence on external temperature, and on external magnetic field of a hydrogen maser. It is compared with another hydrogen maser. Details of the transportation and installation of the maser are given. The hydrogen maser frequency is compared with cesium oscillators to derive long-term behavior

Building an Agent-Based Model for exploring how informal rules impact the functioning of newly-established Water User Associations in Central Asia

International audienceIn transition countries informal institutions play a major role and often interfere with new formal institutions leading to large discrepancies between rules on paper and rules in use. We develop an agent-based model to explore the interaction between formal and informal rules and its effect on the performance of the formal institutions, based on the example of water user associations (WUA) in Uzbekistan. The model is based on field experience such as community-based work and role playing games, complemented by available literature. In this paper we present the conceptualization of the model, its empirical foundation and a first baseline scenario. We model a water user association where rules based on formal and informal institutions can be used. The baseline scenario represents the results of a totally formal WUA. In a next step we will introduce informal rules and explore how they can coexist with formal ones. Further work will bring us to question rules' implementation and roles and relationships evolution through selective rules adoption. The model will allow exploring under which conditions the institution WUA can function well and what might be mechanisms for the selection and adoption of rules by individual members

Dissipation in the superconducting state of kappa-(BEDT-TTF)2Cu(NCS)2

We have studied the interlayer resistivity of the prototypical quasi-two-dimensional organic superconductor $\kappa$-(BEDT-TTF)$_2$Cu(NCS)$_2$ as a function of temperature, current and magnetic field, within the superconducting state. We find a region of non-zero resistivity whose properties are strongly dependent on magnetic field and current density. There is a crossover to non-Ohmic conduction below a temperature that coincides with the 2D vortex solid -- vortex liquid transition. We interpret the behaviour in terms of a model of current- and thermally-driven phase slips caused by the diffusive motion of the pancake vortices which are weakly-coupled in adjacent layers, giving rise to a finite interlayer resistance.Comment: Four pages, three figure