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Model intercomparison studies are carried out to test and compare the simulated outputs of various model setups over the same study domain. The Great Lakes region is such a domain of high public interest as it not only resembles a challenging region to model with its transboundary location, strong lake effects, and regions of strong human impact but is also one of the most densely populated areas in the USA and Canada. This study brought together a wide range of researchers setting up their models of choice in a highly standardized experimental setup using the same geophysical datasets, forcings, common routing product, and locations of performance evaluation across the 1×106 km2 study domain. The study comprises 13 models covering a wide range of model types from machine-learning-based, basin-wise, subbasin-based, and gridded models that are either locally or globally calibrated or calibrated for one of each of the six predefined regions of the watershed. Unlike most hydrologically focused model intercomparisons, this study not only compares models regarding their capability to simulate streamflow (Q) but also evaluates the quality of simulated actual evapotranspiration (AET), surface soil moisture (SSM), and snow water equivalent (SWE). The latter three outputs are compared against gridded reference datasets. The comparisons are performed in two ways – either by aggregating model outputs and the reference to basin level or by regridding all model outputs to the reference grid and comparing the model simulations at each grid-cell. The main results of this study are as follows: The comparison of models regarding streamflow reveals the superior quality of the machine-learning-based model in the performance of all experiments; even for the most challenging spatiotemporal validation, the machine learning (ML) model outperforms any other physically based model. While the locally calibrated models lead to good performance in calibration and temporal validation (even outp

Environmental models are used extensively to evaluate the effectiveness of a range of design, planning, operational, management and policy options. However, the number of options that can be evaluated manually is generally limited, making it difficult to identify the most suitable options to consider in decision-making processes. By linking environmental models with evolutionary and other metaheuristic optimization algorithms, the decision options that make best use of scarce resources, achieve the best environmental outcomes for a given budget or provide the best trade-offs between competing objectives can be identified. This Introductory Overview presents reasons for embedding formal optimization approaches in environmental decision-making processes, details how environmental problems are formulated as optimization problems and outlines how single- and multi-objective optimization approaches find good solutions to environmental problems. Practical guidance and potential challenges are also provided., Accepted Author Manuscript, Sanitary Engineering

Recent advances in SiC power devices and high temperature magnetic and insulation materials has led to an increase in activity to develop compact, high switch rate power system components that can operate at temperatures in excess of 200 degrees C. These efforts have highlighted the need to develop capacitor technology for high power, high frequency power filter applications, which can experience cycling over a wide range of temperature (-55 degrees C to 250 degrees C). A modeling and simulation capability was used to investigate device architecture and electrical performance relationships for a select group of wound and stacked devices, which were then evaluated for use in a power conditioning application. A finite element analysis of the device architectures was used to develop a better understanding of how magnetic fields and thermal profiles affect the performance of the capacitors in maintaining a low ripple voltage at high switch rates (>20 kHz). Both predicted electrical properties and empirical data were utilized as SPICE simulation input parameters to evaluate the performance of the different capacitors in an interleaved DC-DC boost converter model. Of interest is developing a better understanding of how the device architecture and its electrical properties affect its performance as a filtering device in a high power, high frequency application., Submitted for Publication in the Proceedings of the High Temperature Electronics Conference (HITEN) 2010, held in Albuquerque, NM on 11-13 May 2010. The original document contains color images. All DTIC reproductions will be in black and white.