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Sensitivity of a large-scale hydrologic model to quality of input data obtained at different scales;distributed versus stochastic non-distributed modelling

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JOURNAL OF HYDROLOGY 2002年第1-4期264卷 101-112页

作者： Vachaud, G Chen, T Univ Grenoble 1 IRD INPGLab Etud Transferts Hydrol & Environm UMR 5564 CNRSLTHE F-38041 Grenoble 09 France

The amount of information available to run a spatially distributed model is often very much less than the ideal. The aim of this study is to estimate the impact of degradation of information about the spatial distribution of input parameters, and second the scale at which this information is obtained. A well defined agricultural catchment, with an important database concerning spatial and temporal observations has been used for this purpose: the agricultural catchment of la Cote St Andre, 60 km North East of Grenoble in the South East of France. The methodological framework is based on the Areal Non-point Source Watershed Environmental Response Simulation model. A 3 year simulation using georeferenced variables (crops and soil types) and annual changes in crop rotation is first developed as a reference. This is compared to simulations results obtained during the same period, with the same climatic data, but with the following degradation of quality of other inputs: firstly, the spatial distribution of soils and crop is ignored;both variables being defined by their areal coverage obtained from local information;secondly, the same inputs are deduced from a database obtained at the European scale. In both cases, a Latin Hypercube Sampler is used to stochastically generate sets of samples corresponding to the probability distribution of variables. The study is based on comparisons between modelled outputs: drainage of water and leaching of nitrate below the root zone of crops at the catchment scale. When information is local, and in absence of lateral flow (runoff), distributed modelling and purely stochastic modelling provide identical catchment average values;on the contrary, the use of the European database may introduce important biases concerning the proportion of land uses and of soils. In both cases, however, the lack of information concerning the location of sensitive areas in terms of risks of pollution may be considered as an important weakness of stochastic m

关键词： distributed modelling stochastic modelling Latin Hypercube Sampler nitrate leaching groundwater recharge catchment

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Empirically-derived capacitor characteristic formulas from distributed modelling

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IET CIRCUITS DEVICES & SYSTEMS 2007年第2期1卷 117-125页

作者： Brown, R. W. RMIT Univ Melbourne Vic 3001 Australia

Diffusion equation modelling is used to develop formulas for the normally fixed values of capacitance and resistance of the traditional capacitor equivalent circuit. The formulas define the dependence of the equivalent circuit values on metal film resistivity, capacitance per unit area, areal dimensions of the metallisation and on frequency. A multilayer capacitor topology, having both capacitor plates connected at the same end, is used for the derivation, but it is shown that the results are also representative for the more standard double-end connected topologies with some restrictions above the typical self-resonance frequency of these capacitors. The formulas allow accurate prediction of dissipation factor and input impedance according to the design parameters used in constructing the capacitor, thus providing powerful tools in capacitor design. The algorithms also facilitate the determination of internal voltages, currents and power distribution within the capacitor, thus exposing the effects, for example, of partial edge disconnection. The formulas may potentially provide a better capacitor equivalent circuit with dependent variables for circuit emulation. In the paper, the derivation process is described and the formulas tested against experimental results. A simple addition to the equivalent circuit is also included to model dielectric loss which dominantly determines the dissipation factor at low frequency.

关键词： capacitors electric resistance metallisation equivalent series resistance distributed modelling dielectric losses multilayer capacitor topology diffusion equation modelling power distribution equivalent series capacitance dielectric loss internal voltages double-end connected topologies equivalent circuit partial edge disconnection capacitance input impedance dissipation factor metal film resistivity equivalent circuits electric impedance electrical resistivity capacitor characteristic formulas internal currents

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The impact of stormwater management strategies on the flow regime of a peri-urban catchment facing urbanisation and climate change: a distributed modelling study in Lyon, France

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URBAN WATER JOURNAL 2023年第7期20卷 925-942页

作者： Bonneau, Jeremie Branger, Flora Castebrunet, Helene Lipeme Kouyi, Gislain INRAE Villeurbanne CS France Univ Lyon INSA Lyon Villeurbanne France Univ Grenoble Alpes CNRS IRD Grenoble INPIGE Grenoble France

The relative impact of urbanisation (urban sprawl), climate change (rainfall and evapotranspiration) and stormwater disconnection strategies (implementation of green infrastructure (GI)) on a peri-urban stream in the western suburbs of Lyon, France, was investigated using a distributed, physically based model (J2000P). Results showed that ambitious catchment-scale implementation of GI has the potential to mitigate some hydrological effects of urbanisation, especially a drastic reduction of combined sewer overflows. However, GI did not have a large impact on the stream flow regime, especially in the context of climate change, as the stream is dominated by non-urban contributions. Spatially distributed models have the capacity to inform river managers about the extent of implementation of GI needed to achieve given management goals and highlight some limitations of disconnection strategies. Indeed, while GI improved the resilience of sewer networks to global change, it was not sufficient to compensate for the effects of climate change on streamflow.

关键词： distributed modelling urbanisation green infrastructure climate change combined sewer overflows

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A distributed modelling approach to assess the use of Blue and Green Infrastructures to fulfil stormwater management requirements

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LANDSCAPE AND URBAN PLANNING 2018年 173卷 60-63页

作者： Versini, P. -A. Kotelnikova, N. Poulhes, A. Tchiguirinskaia, I. Schertzer, D. Leurent, F. Ecole Ponts ParisTech HMCo Champs Sur Marne France Ecole Ponts ParisTech LVMT Champs Sur Marne France

Blue and Green Infrastructures (B&GI) are nature-based solutions considered as particularly efficient to reduce the potential impact of new and existing developments with respect to stormwater issues. In order to assess their performance at some large scales compatible with urban projects, adapted distributed rainfall-runoff models are required. The latest advancements of the Multi-Hydro platform have made possible the representation of such B &GI. Applied in a virtual new urban development project located in the Paris region, Multi-Hydro has been used to simulate the impact of B&GI implementation, and their ability to fulfil regulation rules authorizing the connexion to the sewer network. The results show that a combination of several B&GI, if they are widely implemented, could represent an efficient tool to meet regulations at the parcel scale, as they can reduce runoff volume about 90%.

关键词： Blue green infrastructures Stormwater management distributed modelling

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Semi-distributed modelling of Stormwater Drains Using Integrated Hydrodynamic EPA-SWM Model 4th

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4th International Conference on Harmony Search, Soft Computing and Applications (ICHSA)

作者： Sinha, M. K. Baier, K. Azzam, R. Baghel, T. Verma, M. K. Chhattisgarh Swami Vivekanand Tech Univ Bhilai India Rhein Westfal TH Aachen Dept Engn Geol & Hydrogeol Aachen Germany

ISBN: (纸本)9789811307614;9789811307607

After becoming a capital city of Chhattisgarh state in 2001, the city Raipur in India has been rapidly growing in terms of population as well as areal expansion. With the process of urbanization and alteration of the natural drainage system, the existing stormwater drainage system became insufficient to drain the area, resulting in a higher risk of flooding. In this study, the effect of urbanization on the runoff generation and peak flow and their impact on the stormwater drainage system have been investigated. Digital land-use data from aerial photograph, satellite images and Differential Global Positioning System (DGPS) survey were used to detect and analyse the shift in land-uses since the evolution of Raipur city. For the same periods, total generated runoff and peak flow as well as flood-prone locations along the drainage network have been simulated. The results showed an increase in build-up area of 99.2, 22.0 and 0.6%, respectively. Agricultural areas increased by 210.8, 157.5 and 0.6%, respectively. Forests and tree covers almost completely disappeared. The higher share of build-up areas led to an increase in total runoff generation and peak flows. The maximum runoff increased by 87.92 x 10(6) L and maximum peak flows changed from 11.03 to 14.09 m(3)/s. The results show significant increase in runoff and peak discharge in the study area due to human intervention, since Raipur city started altering natural drainage system. Moreover, the model can be used for future flood forecasting in Raipur city, and the results from this study can be utilized to develop flood mitigation measured as best management practices in Raipur.

关键词： distributed modelling Urbanization impacts Stormwater management Hydrological uncertainty

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Comparative study of conceptual versus distributed hydrologic modelling to evaluate the impact of climate change on future runoff in unregulated catchments

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JOURNAL OF WATER AND CLIMATE CHANGE 2020年第2期11卷 341-366页

作者： Al-Safi, Hashim Isam Jameel Kazemi, Hamideh Sarukkalige, P. Ranjan Southern Tech Univ Tech Inst Shatrah Dept Irrigat & Drainage Tech Dhi Qar Iraq Curtin Univ Dept Civil Engn Perth WA Australia

The application of two distinctively different hydrologic models, (conceptual-HBV) and (distributed-BTOPMC), was compared to simulate the future runoff across three unregulated catchments of the Australian Hydrologic Reference Stations (HRSs), namely Harvey catchment in WA, and Beardy and Goulburn catchments in NSW. These catchments have experienced significant runoff reduction during the last decades due to climate change and human activities. The Budyko-elasticity method was employed to assign the influences of human activities and climate change on runoff variations. After estimating the contribution of climate change in runoff reduction from the past runoff regime, the downscaled future climate signals from a multi-model ensemble of eight global climate models (GCMs) of the Coupled Model Inter-comparison Project phase-5 (CMIP5) under the Representative Concentration Pathway (RCP) 4.5 and RCP 8.5 scenarios were used to simulate the future daily runoff at the three HRSs for the mid-(2046-2065) and late-(2080-2099) 21st-century. Results show that the conceptual model performs better than the distributed model in capturing the observed streamflow across the three contributing catchments. The performance of the models was relatively compatible in the overall direction of future streamflow change, regardless of the magnitude, and incompatible regarding the change in the direction of high and low flows for both future climate scenarios. Both models predicted a decline in wet and dry season's streamflow across the three catchments.

关键词： Budyko equation climate change conceptual modelling distributed modelling human activities hydrologic reference stations

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Clinical utility of distributed source modelling of interictal scalp EEG in focal epilepsy

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CLINICAL NEUROPHYSIOLOGY 2010年第10期121卷 1726-1739页

作者： Plummer, C. Wagner, M. Fuchs, M. Vogrin, S. Litewka, L. Farish, S. Bailey, C. Harvey, A. S. Cook, M. J. St Vincents Hosp Ctr Clin Neurosci & Neurol Res Fitzroy Vic 3065 Australia Univ Melbourne Dept Med Parkville Vic 3052 Australia Compumed Neuroscan D-20255 Hamburg Germany Royal Childrens Hosp Dept Neurol Parkville Vic 3052 Australia Univ Melbourne Dept Paediat Parkville Vic 3052 Australia

Objective: Assess the clinical utility of non-invasive distributed EEG source modelling in focal epilepsy. Methods: Interictal epileptiform discharges were recorded from eight patients - benign focal epilepsy of childhood (BFEC), four;mesial temporal lobe epilepsy (MTLE), four. EEG source localization (ESL) applied 48 forward-inverse-subspace set-ups: forward - standardized, leadfield-interpolated boundary element methods (BEMs, BEMi), finite element method (FEMi);inverse - minimum norm (MNLS), L1 norm (L1), low resolution electromagnetic tomography (LORETA), standardized LORETA (sLORETA);subspace - whole volume (3D), cortex with rotating sources (CxR), cortex with fixed sources (CxN), cortex with fixed extended sources (patch). Current density reconstruction (CDR) maxima defined 'best-fit'. Results: From 19,200 CDR parameter results and 2304 CDR maps, the dominant variables on best-fit were inverse model and subspace constraint. The most clinically meaningful and statistically robust results came with sLORETA-CxR/patch (lower Rolandic in BFEC, basal temporal lobe in MTLE). Computation time was inverse model dependent: sub-second (MNLS, sLORETA), seconds (L1), minutes (LORETA). Conclusions: From the largest number of distributed ESL approaches compared in a clinical setting, an optimum modelling set-up for BFEC and MTLE incorporated sLORETA (inverse), CxR or patch (subspace), and either BEM or FEMi (forward). Computation is efficient and CDR results are reproducible. Significance: distributed source modelling demonstrates clinical utility for the routine work-up of unilateral BFEC of the typical Rolandic variety, and unilateral MTLE secondary to hippocampal sclerosis. (C) 2010 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

关键词： EEG source localization distributed modelling Dipole BFEC MTLE Focal epilepsy

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Depth-averaged, spatially distributed flow dynamic and solute transport modelling of a large-scaled, subtropical constructed wetland

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HYDROLOGICAL PROCESSES 2010年第19期24卷 2724-2737页

作者： Min, Joong-Hyuk Wise, William R. Univ Florida Dept Soil & Water Sci Gainesville FL 32611 USA Univ Florida Dept Civil & Coastal Engn Gainesville FL 32611 USA

Constructed wetlands are being utilized worldwide to effectively reduce excess nutrients in agricultural runoff and wastewater. Despite their frequency, a multi-dimensional, physically based, spatially distributed modelling approach has rarely been applied for flow and solute transport in treatment wetlands. This article presents a two-dimensional hydrodynamic and solute transport modelling of a large-scaled, subtropical, free water surface constructed wetland of about 8 km(2) in the Everglades of Florida, USA. In this study, MIKE 21 was adopted as the basic model framework. Field monitoring of the time series hydrological and chloride data, as well as spatially distributed data such as bathymetry and vegetation distribution, provided the necessary model input and testing data. Simulated water level profiles were in good agreement with the spatio-temporal variations of measured ones. On average, the root-mean-square error of model calibration on annual water level fluctuations was 0.09 m. Manning's roughness coefficients for the dense emergent and submerged aquatic vegetation areas, which were estimated as a function of vegetation type, ranged from 0.67 to 1.0 and 0.12 to 0.15 s/m(1/3), respectively. The solute transport model calibration for four monitoring sites agreed well with the measured annual variations in chloride concentration with an average percent model error of about 15%. The longitudinal dispersivity was estimated to be about 2 m and was more than an order of magnitude higher than the transverse one. This study is expected to play the role of a stepping stone for future modelling efforts on the development and application of more advanced flow and transport models applicable to a variety of constructed wetland systems, as well as to the Everglades stormwater treatment areas in operation or in preparation. Copyright (c) 2010 John Wiley & Sons, Ltd.

关键词： free water surface constructed wetland hydrodynamics solute transport distributed modelling hydraulic resistance dispersivity

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distributed numerical rainfall-runoff modelling in an arid region using thematic mapper data and a geographical information system

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HYDROLOGICAL PROCESSES 1996年第9期10卷 1229-1242页

作者： Sharma, KD Menenti, M Huygen, J Fernandez, PC Central Arid Zone Research Institute Jodhpur 342003 India DLO — The Winand Staring Centre for Integrated Land Soil and Water Research (SC-DLO) 6700 AC Wageningen the Netherlands Centro Regional Andino — INCYTH 5500 Mendoza Argentina [*]Central Arid Zone Research Institute Jodhpur 342003 India

The rainfall-runoff process consists of an excess rainfall process and a runoff concentration process. A transient one-dimensional finite difference model describing the partitioning of precipitation between surface runoff, soil moisture storage and deep percolation, through the coupling of saturated-unsaturated zones, has been implemented in a geographical information system including data on vegetation cover derived from the Landsat Thematic Mapper. The model has been used to simulate both the rainfall excess and the resultant outflow hydrographs for a small arid zone drainage basin in the Andean region of Argentina. The overall hydrograph shape, peak discharge, runoff volume and flow duration are predicted within a relative squared error of 13.2%. The spatial input data and the model structure are discussed and suggestions for applications to larger complex basins and for future refinements in the technique are presented.

关键词： remote sensing distributed modelling SWAMREG vegetation index runoff hydrograph geographical information systems

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Flood modelling with GIS-derived distributed unit hydrographs

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HYDROLOGICAL PROCESSES 1996年第10期10卷 1401-1409页

作者： Muzik, I Professor of Civil Engineering The University of Calgary Calgary Alberta T2N 1N4 Canada [*]Professor of Civil Engineering The University of Calgary Calgary Alberta T2N 1N4 Canada

The concept of a spatially distributed unit hydrograph is based on the fact that the unit hydrograph can be derived from the time-area curve of a watershed by the S-curve method. The time-area diagram is a graph of cumulative drainage area contributing to discharge at the watershed outlet within a specified time of travel. Accurate determination of the time-area diagram is made possible by using a GIS. The GIS is used to describe the connectivity of the links in the watershed flow network and to calculate distances and travel times to the watershed outlet for various points within the watershed. Overland how travel times are calculated by the kinematic wave equation for time to equilibrium;channel flow times are based on the Manning and continuity equations. To account for channel storage, travel times for channel reaches are increased by a percentage depending on the channel reach length and geometry. With GIS capability for rainfall mapping, the assumption of a uniform spatial rainfall distribution is no longer necessary;hence the term, spatially distributed unit hydrograph. An example of the application for the Waiparous Creek in the Alberta Foothills is given. IDRISI is used to develop a simple digital elevation model of the 229 km(2) watershed, using 1 km x 1 km grid cells. A grid of how directions is developed and used to create an equivalent channel network. Excess rainfall for each I km x 1 km cell is individually computed by the Soil Conservation Service (SCS) runoff curve method and routed through the equivalent channel network to obtain the time-area curve. The derived unit hydrograph gave excellent results in simulating an observed flood hydrograph. The distributed unit hydrograph is no longer a lumped model, since it accounts for internal distribution of rainfall and runoff. It is derived for a watershed without the need for observed rainfall and discharge data, because it is essentially a geomorphoclimatic approach. As such, it allows the derivation of

关键词： unit hydrograph time-area diagram lumped modelling distributed modelling geographic information system hydrology flood prediction

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