Tradeoffs among watershed model calibration targets for parameter estimation

La Functional Urban Area (FUA) di Milano è un’area densamente popolata (2.254.263 abitanti) dove l’approvvigionamento idrico è garantito esclusivamente mediante prelievi idrici sotterranei. Per questa ragione la protezione della qualità delle falde rientra tra le priorità delle politiche ambientali di Regione Lombardia. Recentemente è stato avviato un programma di studi ed interventi aventi lo scopo d’individuare i principali plumes di contaminazione da solventi clorurati distinguendone l’impatto da quello legato all’inquinamento diffuso. In questo articolo si presenta il modello di flusso sviluppato per il settore NE della FUA di Milano, settore utilizzato quale area pilota per sviluppare e testare una nuova metodologia che combina statistica e modellistica al fine di distinguere il contributo delle fonti di contaminazione puntuale rispetto a quelle diffuse.

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Global optimization for watershed model calibration

Water Science and Application - Calibration of Watershed Models ◽

10.1029/ws006p0089 ◽

2003 ◽

pp. 89-104 ◽

Cited By ~ 23

Author(s):

Qingyun Duan

Keyword(s):

Global Optimization ◽

Model Calibration ◽

Watershed Model

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Cavitation Model Calibration Using Machine Learning Assisted Workflow

Mathematics ◽

10.3390/math8122107 ◽

2020 ◽

Vol 8 (12) ◽

pp. 2107

Author(s):

Ante Sikirica ◽

Zoran Čarija ◽

Ivana Lučin ◽

Luka Grbčić ◽

Lado Kranjčević

Keyword(s):

Machine Learning ◽

Parameter Estimation ◽

Model Calibration ◽

Three Dimensional ◽

Test Case ◽

Assessment Methodology ◽

Cavitation Model ◽

Universal Solution ◽

Thrust And Torque ◽

Empirical Constants

Conventional cavitation assessment methodology in industrial and scientific applications generally depends on cavitation models utilizing homogeneous mixture assumption. These models have been extensively assessed, modified and expanded to account for deficiencies of their predecessors. Unfortunately, none of the proposed models can be classified as the universal solution for all engineering applications, with usage mainly directed by experience or general availability of the models. In this study we propose a workflow through which the empirical constants governing the phase change of the Kunz mixture cavitation model can be calibrated for a given application or a series of problems, with machine learning as a tool for parameter estimation. The proposed approach was validated on a three-dimensional propeller test case with results in excellent agreement for the case in question. Results for thrust and torque were within 2% with cavity extents differing by up to 20%. This is a significant improvement when compared to previously proposed parameters. Despite the lack of generalization due to the limited nature of the dataset on which the model was trained, the proposed parameters entail acceptable results for similar cases as well. The overall methodology is applicable to other problems as well and should lead to more accurate cavitation predictions.

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Assessment on activated sludge models for acetate biodegradation under aerobic conditions

Water Science & Technology ◽

10.2166/wst.2009.446 ◽

2009 ◽

Vol 60 (4) ◽

pp. 983-994 ◽

Cited By ~ 2

Author(s):

M. A. Hoque ◽

V. Aravinthan ◽

N. M. Pradhan

Keyword(s):

Parameter Estimation ◽

Activated Sludge ◽

Model Calibration ◽

Aerobic Biodegradation ◽

Batch Experiments ◽

Storage Model ◽

Biodegradation Process ◽

Ammonia Degradation ◽

And Storage ◽

Activated Sludge Models

A comparison of four different established models along with parameter estimation was carried out in order to explain the aerobic biodegradation of acetate in an activated sludge system. These models were investigated using experimental OUR data from batch experiments of three different concentration studies. Model calibration reveals that ASM1 model is not suitable to explain the observed experimental OUR during the famine phase implying storage compounds could play an important role during that stage. Besides, the model corresponds to the accumulation concept and is not well fitted for all concentrations studies though it includes the storage phenomena. Both the ASM3 model and the model for simultaneous storage and growth on substrate can well describe the acetate biodegradation process, however the OUR data alone is not sufficient to justify the suitability of those models. Simulated profiles using the model outputs demonstrate that storage is overestimated while ammonia degradation is underestimated in ASM3 compared to simultaneous growth and storage model. The current study also gives reasonable outcomes related to parameter estimation as compared with previous study which is statistically interpreted in this paper.

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Hydrological modeling of the Ribeirão das Posses – An assessment based on the Agricultural Ecosystem Services (AgES) watershed model

Ambiente e Agua - An Interdisciplinary Journal of Applied Science ◽

10.4136/ambi-agua.2073 ◽

2017 ◽

Vol 12 (3) ◽

pp. 351 ◽

Cited By ~ 1

Author(s):

Patrícia Porta Nova da Cruz ◽

Timothy R. Green ◽

Ricardo De Oliveira Figueiredo ◽

Anderson Soares Pereira ◽

Holm Kipka ◽

...

Keyword(s):

Ecosystem Services ◽

Model Calibration ◽

Native Species ◽

Hydrological Modeling ◽

Stream Water ◽

Southeastern Brazil ◽

Water Yield ◽

Watershed Model ◽

Agricultural Ecosystem ◽

Daily Streamflow

Southeastern Brazil has recently experienced drought conditions that have impacted watershed conservation and the management of water quality and quantity for agricultural and urban demands. The Ribeirão das Posses watershed is being monitored as a headwater of the Jaguarí River, which is one of the contributing rivers of the Cantareira Reservoir Complex in the state of São Paulo. The landscape has changed over the last century from native forests to more homogeneous vegetation for pastures, crops and some forest plantations of eucalyptus, which have cumulative impacts on water yield and quality. Currently, the Projeto Conservador das Águas (Water Conservationist Project) has planted small areas with native species vegetation in order to recover degraded areas. The objective of this study was to evaluate the quantity of water in the Ribeirão das Posses Basin by both measurements and by simulating hydrological responses. The Agricultural Ecosystem Services (AgES) watershed model was applied to simulate water movement and storage among land areas. The simulation period was from 2009 to 2014, because the daily streamflow and meteorological data were available for model calibration and testing. We discuss data input requirements, model calibration to fit measured streamflow, and sensitivity to spatially variable rainfall inputs. The calibrated model may be used to estimate streamflow during periods of missing data, and in the future to estimate impacts of land use changes on stream water quantity and quality. Such information can be used in programs of payments for ecosystem services.

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