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Streamflow is one of the most important variables in hydrology, but it is difficult to measure continuously. As a result, nearly all streamflow time series are estimated from rating curves that define a mathematical relationship between streamflow and some easy-to-measure proxy like water surface elevation (stage). Despite the existence of automated methods, most rating curves are still fit manually, which can be time-consuming and subjective. Although several automated methods exist, they vary greatly in performance because of the non-convex nature of the problem. In this work, we develop a parameterization of the segmented power law that works reliably with minimal data, which could serve operationally or as a benchmark for evaluating other methods. The model, along with test data and tutorials, is available as an open-source Python package called ratingcurve. The implementation uses a modern probabilistic machine-learning framework, which is relatively easy to modify so that others can improve upon it. [ABSTRACT FROM AUTHOR]

Thin films of Au ranging from 7-24 nm were grown on MoS2 at room temperature using thermal evaporation and studied using scanning tunneling microscopy and ballistic electron emission spectroscopy. Topographic images show the surface morphology of Au transitions from terraced triangles to a mix of terraced hexagonal and irregular-shaped structures as film thickness exceeded 16 nm. Raman spectra reveal the presence of tensile strain in the MoS2 with thicker Au films and is likely the driving force behind this transition. All samples exhibit a Schottky barrier significantly lower than that predicted by the Schottky-Mott model due to Fermi-level pinning at the interface. The pinning mechanism is thought to be caused, in part, by the presence of gap states induced by a weakening of the interlayer Mo-S bonding in the presence of the Au film. Although relatively consistent in thinner films, the Schottky barrier increases concurrently with structural changes on the surface. At the same time, transmission through the interface begins to drop at an increased exponential rate with film thickness. These observations are consistent with a widening separation between the Au and MoS2 that would reduce the number of gap states and cause transmission through the interface to be more characteristic of quantum tunneling. An increased separation such as this could result from changes in equilibrium conditions at the interface with increasing strain. [ABSTRACT FROM AUTHOR]