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Multi-criteria Evaluations (multi-criteria + evaluation)
Selected AbstractsTowards a simple dynamic process conceptualization in rainfall,runoff models using multi-criteria calibration and tracers in temperate, upland catchmentsHYDROLOGICAL PROCESSES, Issue 3 2010C. Birkel Abstract Empirically based understanding of streamflow generation dynamics in a montane headwater catchment formed the basis for the development of simple, low-parameterized, rainfall,runoff models. This study was based in the Girnock catchment in the Cairngorm Mountains of Scotland, where runoff generation is dominated by overland flow from peaty soils in valley bottom areas that are characterized by dynamic expansion and contraction of saturation zones. A stepwise procedure was used to select the level of model complexity that could be supported by field data. This facilitated the assessment of the way the dynamic process representation improved model performance. Model performance was evaluated using a multi-criteria calibration procedure which applied a time series of hydrochemical tracers as an additional objective function. Flow simulations comparing a static against the dynamic saturation area model (SAM) substantially improved several evaluation criteria. Multi-criteria evaluation using ensembles of performance measures provided a much more comprehensive assessment of the model performance than single efficiency statistics, which alone, could be misleading. Simulation of conservative source area tracers (Gran alkalinity) as part of the calibration procedure showed that a simple two-storage model is the minimum complexity needed to capture the dominant processes governing catchment response. Additionally, calibration was improved by the integration of tracers into the flow model, which constrained model uncertainty and improved the hydrodynamics of simulations in a way that plausibly captured the contribution of different source areas to streamflow. This approach contributes to the quest for low-parameter models that can achieve process-based simulation of hydrological response. Copyright © 2009 John Wiley & Sons, Ltd. [source] Weighting methodologies in multi-criteria evaluations of combined heat and power systemsINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 12 2009Jiang-Jiang Wang Abstract Several combined heat and power (CHP) system options are presented to assess and compare with respect to the end users' requirements. According to the obtained data from literature, 16 kinds of CHP systems are evaluated using gray relational method in multi-criteria, such as technology, economy, environment, and society. The results depend greatly on the criteria weights in multi-criteria evaluations. Aiming to obtain rational result, this paper reviews the weighting method briefly and proposes an optimal combined weighting method to consider the subjectivity of decision-maker and the objectivity of measurement data. The singular value decomposition aggregation method is employed to verify the rationality of evaluation result. Through multi-criteria evaluation and discussions, the combination weighting method is recommended to be used in the selection of CHP schemes. Finally, the best CHP system is selected and the most conspicuous factors having great impact on CHP system with respect to the users' requirements are given out. Copyright © 2009 John Wiley & Sons, Ltd. [source] | ||||||||||