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Creating Advanced Fire-Spreading Models Using The Cd++ Toolkit, Gabriel Wainer Jul 2006

Creating Advanced Fire-Spreading Models Using The Cd++ Toolkit, Gabriel Wainer

International Congress on Environmental Modelling and Software

Recent research efforts focused on the creation of fire spreading models using Cellular models. The Cell-DEVS formalism and the CD++ toolkit allow the user to construct their applications using simple and more intuitive model specification, which can execute with high efficiency using a discrete event approach. It was shown that different environmental applications can be easily faced, allowing the study of complex problems through simulation. The use of formal base improves the development, checking and maintaining phases, facilitating the testing and reuse of their components. The utilization of a discrete event formalism such as these ones can provide better precision …

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Ten Steps Applied To Development And Evaluation Of Process-Based Biogeochemical Models Of Estuaries, Barbara J. Robson, Ian T. Webster, David P. Hamilton, Terence Chan, Teemu Kokkonen Jul 2006

Ten Steps Applied To Development And Evaluation Of Process-Based Biogeochemical Models Of Estuaries, Barbara J. Robson, Ian T. Webster, David P. Hamilton, Terence Chan, Teemu Kokkonen

International Congress on Environmental Modelling and Software

The procedures involved in model development may be set out ten-step process, beginning with defining the purpose of the model and ending with evaluation of the appropriateness and utility of the completed model. This process, recently outlined by Jakerman et al. [2006], is often iterative as model development is a continuous process that refines and improves the indented capacity of the model. Here, we show how the ten steps of model development are relevant to process-based biogeochemical modeling of aquatic systems, using examples from two case studies: a model of phytoplankton succession and nutrient concentrations in the Swan-Canning Estuary (Western …

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Optimal Regional Partitioning For Wildfire Risk Characterization, Paolo Fiorucci, F. Gaetani, R. Minciardi Jul 2006

Optimal Regional Partitioning For Wildfire Risk Characterization, Paolo Fiorucci, F. Gaetani, R. Minciardi

International Congress on Environmental Modelling and Software

The efficiency of fire prevention and fire-fighting organization are strictly related with the identification of the elementary Administrative Units, whose physical characteristics and number/quality of resources affect significantly the occurrence and the dynamics of the considered phenomenon. In fact, wildland fire risk is determined by several factors such as vegetation, local climate condition, topography, socio-economical aspects, and, of course, wildfire fighting available resources. A power law distribution can be used to represent the frequency-area relationship empirical wildfire data. Thus, it is possible to think of characterizing a region by its wildland fire regime, which can be defined by the power …

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Nesting Genetic Algorithms To Solve A Robust Optimal Experimental Design Problem, Dirk J. W. De Pauw, Peter A. Vanrolleghem Jul 2006

Nesting Genetic Algorithms To Solve A Robust Optimal Experimental Design Problem, Dirk J. W. De Pauw, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

When calibrating a (dynamic) model, one is often faced with a lack of information-rich data. Without such data, there is little hope in obtaining accurate parameter estimates. In order to improve the situation, optimal experimental design for parameter estimation (OED-PE) can be employed. The main drawback of the classical OED-PE methodology is that values for the model parameters need to be provided in order to obtain an optimal design. If the values of the model parameters are highly uncertain, robust OED-PE should be preferred, yielding a design which guarantees a certain information content given the parameter uncertainty. This approach adds …

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Rainfall–Streamflow–Air Temperature Datasets (And Catchment Information) Available Internationally To Assist With Pub Decade Top-Down Modelling, B. F. W. Croke, I. G. Littlewood, D. A. Post Jul 2006

Rainfall–Streamflow–Air Temperature Datasets (And Catchment Information) Available Internationally To Assist With Pub Decade Top-Down Modelling, B. F. W. Croke, I. G. Littlewood, D. A. Post

International Congress on Environmental Modelling and Software

One of the purposes of the Top-Down modelling Working Group (TDWG) within the Prediction in Ungauged Basins (PUB) Initiative of the International Association of Hydrological Sciences (IAHS) is to use available data (including new datasets – e.g. remote sensing products) to test existing rainfall-runoff models and develop new models. As such, effort has been made to collate data for a wide variety of catchments distributed over the globe. The first datasets obtained are for the UK, USA and Australia, yielding a total of 830 catchments. This paper describes the datasets, and presents an example of data analysis techniques that are …

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Moira-Plus: A Decision Support System For The Management Of Complex Fresh Water Ecosystems Contaminated By Radionuclides And Heavy Metals, Luigi Monte, Lars Håkanson, D. Hofman, John Brittain, Eduardo Gallego, Antonio Jimenez, Giacomo Angeli Jul 2006

Moira-Plus: A Decision Support System For The Management Of Complex Fresh Water Ecosystems Contaminated By Radionuclides And Heavy Metals, Luigi Monte, Lars Håkanson, D. Hofman, John Brittain, Eduardo Gallego, Antonio Jimenez, Giacomo Angeli

International Congress on Environmental Modelling and Software

The accidental release of radioactive substances into the environment leads to the necessity of applying suitable countermeasures for the restoration of the polluted environment. However, despite their obvious benefits, such interventions may result in detrimental effects of economic, ecological and social nature that must be carefully evaluated. MOIRA–PLUS is a PC-based user-friendly, Computerised Decision Support System (CDSS) that helps decision makers to choose optimal countermeasure strategies for different kinds of aquatic ecosystems and contamination scenarios. CDSS MOIRA-PLUS is based on: a) Validated models to evaluate the behaviour of radionuclides in contaminated water bodies and biota and to assess the effect …

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A Multi-Objective Approach For Sustainable Municipal Solid Waste (Msw) Management, R. Minciardi, Massimo Paolucci, M. Robba, Roberto Sacile Jul 2006

A Multi-Objective Approach For Sustainable Municipal Solid Waste (Msw) Management, R. Minciardi, Massimo Paolucci, M. Robba, Roberto Sacile

International Congress on Environmental Modelling and Software

A multi-objective approach to sustainable Municipal Solid Waste (MSW) management is presented, with the aim of supporting the decisions about the optimal flows of solid waste to be sent to landfill, recycling and to the different treatment plants. To achieve this goal, an approach is proposed in which the decision makers (DMs) are interactively involved in the decision process, following the reference point methodology [Wierzbicki et al, 2002]. The method can be viewed as an integration/modification of techniques already introduced in the literature. The purpose of the DMs is to determine the various flows of the different materials in the …

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The Role Of Artificial Neural Network Models In Developing A Regional Wastewater Reclamation Facility For Beaufort, Sc, Usa, Paul A. Conrads, Edwin Roehl, William Martello, Edward Saxon Jul 2006

The Role Of Artificial Neural Network Models In Developing A Regional Wastewater Reclamation Facility For Beaufort, Sc, Usa, Paul A. Conrads, Edwin Roehl, William Martello, Edward Saxon

International Congress on Environmental Modelling and Software

Beaufort and Jasper Counties are two rapidly growing coastal counties in South Carolina. According to the 2000 census, the region grew by 40 percent during the preceding 10 years. The population growth has increased the quantity of wastewater in the area. The Beaufort River is a complex tidal river system that is home to shellfish grounds, fisheries nursery habitats, and extensive recreation by the local community. The river also serves as receiving water for treated wastewater from military and civilian wastewater reclamation facilities (WRF). Although not uncommon for coastal areas, the river is on the South Carolina list of impaired …

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Evaluation Of The Scale Dependence Of A Spatially-Explicit Hillslope Sediment Delivery Ratio Model, A. E. Kinsey-Henderson, D. A. Post Jul 2006

Evaluation Of The Scale Dependence Of A Spatially-Explicit Hillslope Sediment Delivery Ratio Model, A. E. Kinsey-Henderson, D. A. Post

International Congress on Environmental Modelling and Software

Approximately 90-95% of soil eroded on a hillslope is redeposited and does not enter a stream. However, sediment transport models such as SedNet require an estimate to be made of the actual delivery of sediment from a hillslope into a stream based on predictions of hillslope erosion. In a companion paper in this volume (Post et al. 2006) we have developed a spatially explicit hillslope delivery model based on travel time and applied it to erosion estimates (based on the Revised Universal Soil Loss Equation, RUSLE) for a small subcatchment of the Burdekin River, Weany Creek (13.5km2), at 5m grid …

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Identification Of Alternatives Strengths And Weaknesses During The Conceptual Design Of Environmental Systems, Xavier Flores Alsina, Manel Poch, Laureano Jiménez, Rene Bañares-Alcántara, Ignasi Rodríguez Roda Jul 2006

Identification Of Alternatives Strengths And Weaknesses During The Conceptual Design Of Environmental Systems, Xavier Flores Alsina, Manel Poch, Laureano Jiménez, Rene Bañares-Alcántara, Ignasi Rodríguez Roda

International Congress on Environmental Modelling and Software

The objective of this paper is to present a systematic procedure to support environmental engineers during the evaluation of alternative options, identifying both, the strong and weak points of their decisions. The evaluation of alternative options in the design of environmental systems is complex because several objectives must be considered simultaneously (e.g. environmental, technical, economical, legal), i.e. the problem is multicriteria. The systematic procedure presented consists of three steps: 1) multicriteria decision analysis (MCDA), where the best alternative is selected among the most promising options by evaluating the degree of accomplishment of several design objectives; 2) sensitivity analysis, where multidimensional …

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Neural Identification Of Fuzzy Anomalies In Pressurized Water Systems, Joaquín Izquierdo, R. Pérez, P. A. López, P. L. Iglesias Jul 2006

Neural Identification Of Fuzzy Anomalies In Pressurized Water Systems, Joaquín Izquierdo, R. Pérez, P. A. López, P. L. Iglesias

International Congress on Environmental Modelling and Software

The objective of a Water Supply System (WSS) is to convey treated water to consumers through a pressurized network of pipes. A number of meters and gauges are used to take continuous or periodic measurements that are sent via a telemetry system to the control and operation centre and used to monitor the network. Using this typically limited number of measures together with demand predictions the state of the system must be assessed. Suitable state estimation is of paramount importance in diagnosing leaks and other anomalies in WSS. But this task can be really cumbersome, if not unattainable, for human …

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Current Trends In Environmental Modelling With Uncertainty., Jiří Hřebíček, Jan Pesl Jul 2006

Current Trends In Environmental Modelling With Uncertainty., Jiří Hřebíček, Jan Pesl

International Congress on Environmental Modelling and Software

The important characteristic feature of environmental modelling is the complexity and uncertainty of its mathematical representation (uncertainty of formula). Imprecision of its input data is another characteristic feature, where it is not possible to omit influences of primary monitoring (e.g. gaps of data, errors of measuring facilities, human factor, etc). Many parameters in algorithms and their mathematical formulations are substituted by empirical constants in praxis, although it is well known that their values are very volatile and input data are not validated. Nowadays, information and communication technology (ICT) capabilities are growing rapidly and applied mathematical software (e.g. computer algebra systems, …

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Uncertainty In Environmental Decision-Making: Issues, Challenges And Future Directions, Holger R. Maier, James C. Ascough Ii Jul 2006

Uncertainty In Environmental Decision-Making: Issues, Challenges And Future Directions, Holger R. Maier, James C. Ascough Ii

International Congress on Environmental Modelling and Software

Environmental decision-making is complicated by the complexity of natural systems and the often competing needs of multiple stakeholders. Modelling tools are often used to assist at various stages of the environmental decision-making process. If such models are to provide effective decision support, the uncertainties associated with all aspects of the decision-making process need to be taken into account explicitly. However, as models become more complex in order to better represent integrated environmental, social and economic systems, achieving this goal becomes more difficult. Some of the important issues that need to be addressed in relation to the incorporation of uncertainty in …

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Construction Of A Degree-Day Snow Model In The Light Of The Ten Iterative Steps In Model Development, Teemu Kokkonen, Harri Koivusalo, Tony Jakeman, J. P. Norton Jul 2006

Construction Of A Degree-Day Snow Model In The Light Of The Ten Iterative Steps In Model Development, Teemu Kokkonen, Harri Koivusalo, Tony Jakeman, J. P. Norton

International Congress on Environmental Modelling and Software

Jakeman et al. (2005) discuss minimum standards for model development and reporting and offer an outline of ten iterative steps to be used in model development. They present the main steps and give examples of what each step might include (especially what choices are to be made), without attempting the formidable task of compiling a comprehensive check list of the model-development process. This study reports construction of a simple degree-day snowmelt model in the light of the ten iterative steps. Such a modelling approach has been widely used in operational hydrology, where the motivation is to produce as reliable as …

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Creating Advanced Fire-Spreading Models Using The Cd++ Toolkit, Gabriel Wainer Jul 2006

Creating Advanced Fire-Spreading Models Using The Cd++ Toolkit, Gabriel Wainer

International Congress on Environmental Modelling and Software

Recent research efforts focused on the creation of fire spreading models using Cellular models. The Cell-DEVS formalism and the CD++ toolkit allow the user to construct their applications using simple and more intuitive model specification, which can execute with high efficiency using a discrete event approach. It was shown that different environmental applications can be easily faced, allowing the study of complex problems through simulation. The use of formal base improves the development, checking and maintaining phases, facilitating the testing and reuse of their components. The utilization of a discrete event formalism such as these ones can provide better precision …

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Supporting Multidisciplinary Model-Based Water Management Projects: A User Perspective, Huub Scholten, Ayalew Kassahun Jul 2006

Supporting Multidisciplinary Model-Based Water Management Projects: A User Perspective, Huub Scholten, Ayalew Kassahun

International Congress on Environmental Modelling and Software

Multidisciplinary model-based water management is a complex process. Projects that have to follow this process may encounter many problems, related to miscommunication, malpractice, misuse of the model, insufficient knowledge of the modeled problems and overselling of model capabilities. This leads to model projects, which are not transparent and difficult to audit. The knowledge-based system consists of an ontological knowledge base (KB) with ‘best modelling practices’ for teams, which members have different disciplinary backgrounds and play different roles in a project, and a Modelling Support Tool (MoST). MoST generates and presents guidelines from the KB on what to do. MoST also …

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Integrated Assessment Of Agricultural And Environmental Policies – Towards A Computerized Framework For The Eu (Seamless-If), Martin Van Ittersum, Frank Ewert, Johanna Alkan Olsson, Erling Andersen, Irina Bezlepkina, Floor Brouwer, Marcello Donatelli, Guillermo Flichman, Thomas Heckelei, Lennart Olsson, Alfons Oude Lansink, Andrea-Emilio Rizzoli, Tamme Van Der Wal, Jacques Wery Jul 2006

Integrated Assessment Of Agricultural And Environmental Policies – Towards A Computerized Framework For The Eu (Seamless-If), Martin Van Ittersum, Frank Ewert, Johanna Alkan Olsson, Erling Andersen, Irina Bezlepkina, Floor Brouwer, Marcello Donatelli, Guillermo Flichman, Thomas Heckelei, Lennart Olsson, Alfons Oude Lansink, Andrea-Emilio Rizzoli, Tamme Van Der Wal, Jacques Wery

International Congress on Environmental Modelling and Software

Agricultural systems continuously evolve and are forced to change as a result of a range of global and local driving forces. Agricultural and environmental policies are increasingly designed to contribute to the sustainability of agricultural systems and to enhance contributions of agricultural systems to sustainable development at large. The effectiveness and efficiency of such polices in realizing desired contributions could be greatly enhanced if it were possible to perform ex-ante assessments. The European Commission has recently introduced impact assessment of its policies as an essential step in policy development. This paper presents the design and first prototype of a computerized …

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Scenario Analysis In Water Resources Management Under Data Uncertainty, Antonio Manca, Giovanni M. Sechi, Andrea Sulis, Paola Zuddas Jul 2006

Scenario Analysis In Water Resources Management Under Data Uncertainty, Antonio Manca, Giovanni M. Sechi, Andrea Sulis, Paola Zuddas

International Congress on Environmental Modelling and Software

In water resources management problems, uncertainty is mainly associated with the value of hydrological exogenous inflows and demand patterns. Deterministic models are inadequate to represent these problems and traditional stochastic optimization models cannot be used if there is insufficient statistical information to support the model. In this paper the uncertainty is modelled by a scenario approach in a multistage environment which includes different possible system configurations in a wide time horizon. A robust chance optimization model is used in order to obtain a so-called barycentric value with respect to decision variables. The successive reoptimization step, based on this barycentric solution, …

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Ten Iterative Steps In Development And Evaluation Of Environmental Models, A. J. Jakeman, R. A. Letcher, J. P. Norton Jul 2006

Ten Iterative Steps In Development And Evaluation Of Environmental Models, A. J. Jakeman, R. A. Letcher, J. P. Norton

International Congress on Environmental Modelling and Software

Models are increasingly being relied upon to inform and support natural resource management. They are incorporating an ever broader range of disciplines and now often confront people without strong quantitative or model-building backgrounds. These trends imply a need for wider awareness of what constitutes good model-development practice, including reporting of models to users and sceptical review of models by users. To this end the paper outlines ten basic steps of good, disciplined model practice. The aim is to develop purposeful, credible models from data and prior knowledge, in consort with end-users, with every stage open to critical review and revision. …

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Modelling Lava Flow To Assess Hazard On Mount Etna (Italy). From Geological Data To A Preliminary Hazard Map, E. Bertino, M. L. Damiani, G. Groppelli, G. Norini, B. Aldighieri, S. Borgonovo, F. Comoglio, G. Pasquaré Jul 2006

Modelling Lava Flow To Assess Hazard On Mount Etna (Italy). From Geological Data To A Preliminary Hazard Map, E. Bertino, M. L. Damiani, G. Groppelli, G. Norini, B. Aldighieri, S. Borgonovo, F. Comoglio, G. Pasquaré

International Congress on Environmental Modelling and Software

In this paper we present a systematic approach to the development of the lava flow hazard map forthe Mount Etna, the most important active volcano in Europe. The basic idea is to determine the hazard zonesby simulating the lava flows originated from a number of sample points localized in regions at high densityof vents, called eruption zones. The key choice is the adoption of a probabilistic model for the simulation ofthe lava flow. In the paper we outline the characteristics of the model, called ELFM, and how it has beenvalidated. On the other side, for the determination of the eruption …

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Air Quality Modelling: State-Of-The-Art, R. San José, A. Baklanov, R. S. Sokhi, Kostas Karatzas, J. L. Pérez Jul 2006

Air Quality Modelling: State-Of-The-Art, R. San José, A. Baklanov, R. S. Sokhi, Kostas Karatzas, J. L. Pérez

International Congress on Environmental Modelling and Software

Air quality modeling is an area with a significant progress and interest during the last two decades. It covers all aspects related to pollution dispersion and impact on different ecosystems. It is very much related to the meteorological field since the atmosphere is governed by the general laws derived by the Navier-Stokes equation system. Progress in computer capabilities during the last decades has impulse substantially the research on air quality modeling in a parallel way. Air pollution modeling covers a very complex and interdisciplinary area where we include remote sensing – land use impact -, initial and boundary conditions, data …

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Impacts Of Agriculture And Dairy Farming On Groundwater Quality: An Optimization Problem, Tomaz Dentinho, R. Minciardi, M. Robba, Roberto Sacile, V. Silva Jul 2006

Impacts Of Agriculture And Dairy Farming On Groundwater Quality: An Optimization Problem, Tomaz Dentinho, R. Minciardi, M. Robba, Roberto Sacile, V. Silva

International Congress on Environmental Modelling and Software

A decision model for groundwater quality preservation in areas affected by intensive agriculture and dairy farming, with specific reference to the Azores islands, is presented. In these islands, the exigency to find appropriate instruments to support decisions in Integrated Water Management (IWM) is particularly felt because the increase of tourism and the dairy farming have increased water demands and depletion of water quality. An optimization problem, in terms of decision variables, objectives, and constraints is formalized. The physical/chemical/ecological models are embedded as constraints in the decision model. Specifically, four types of models (hydraulic model, chemical model, agricultural model, and dairy …

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Bayesian Decision Networks - Going Beyond Expert Elicitation For Parameterisation And Evaluation Of Ecological Endpoints., C. A. Pollino, Barry T. Hart Jul 2006

Bayesian Decision Networks - Going Beyond Expert Elicitation For Parameterisation And Evaluation Of Ecological Endpoints., C. A. Pollino, Barry T. Hart

International Congress on Environmental Modelling and Software

Ecological and integrative analyses routinely involve the synthesis of a range of information sources into a single model. Bayesian decision networks (BDN) are increasingly being used for this purpose because they are flexible, transparent and relatively easy to use. Indeed, BDNs offer a scientific and pragmatic approach to improve decision-making in environmental management, directly addressing management needs, while promoting stakeholder participatory processes. However, despite their advantages, many BDNs developed to meet such needs are not being developed or applied to their full potential. The majority of BDNs published to date rely only on expert opinion to parameterise and evaluate ecologically …

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Hydrological Characterisation Of Four Brazilian Catchments Using A Simple Rainfall-Streamflow Model, I. G. Littlewood, R. T. Clarke, W. Collischonnb, B. F. W. Croke Jul 2006

Hydrological Characterisation Of Four Brazilian Catchments Using A Simple Rainfall-Streamflow Model, I. G. Littlewood, R. T. Clarke, W. Collischonnb, B. F. W. Croke

International Congress on Environmental Modelling and Software

A rainfall–streamflow model featuring a unit hydrograph component is applied to four Brazilian catchments to characterise and quantify their quite different dynamic rainfall–streamflow behaviours. Using only catchment size (km2) and time series of daily rainfall, streamflow and air temperature, six dynamic response characteristics (DRCs) are estimated for each catchment. The DRCs include decay time constants for dominant quick- and slow-response components of streamflow, a time-averaged relative volumetric contribution to streamflow from slow flow (i.e. a slow flow index, SFI) and the size of a conceptual catchment wetness store. The six DRCs are compared for the four catchments in the context …

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Avoiding The Finite Difference Sensitivity Analysis Deathtrap By Using The Complex-Step Derivative Approximation Technique, Dirk J. W. De Pauw, Peter A. Vanrolleghem Jul 2006

Avoiding The Finite Difference Sensitivity Analysis Deathtrap By Using The Complex-Step Derivative Approximation Technique, Dirk J. W. De Pauw, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

In this paper, the complex-step derivative approximation technique will be used for calculating local sensitivity functions. This technique is compared to the finite difference approximation, probably the most used local sensitivity analysis technique. For this comparison, 4 biotechnological models with varying model complexity were used. A well known problem of the finite difference approximation is the choice of a suitable perturbation factor in order to avoid non-linear model effects or numerical errors due to the subtraction of almost equal numbers. The main advantage of the complex-step derivative approximation technique is that it is not susceptible to errors introduced by small …

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Rank-Equivalence Method For Sensitivity Analysis Of An Integrated Model Of A River Catchment, J. K. Ravalico, Graeme C. Dandy, Holger R. Maier Jul 2006

Rank-Equivalence Method For Sensitivity Analysis Of An Integrated Model Of A River Catchment, J. K. Ravalico, Graeme C. Dandy, Holger R. Maier

International Congress on Environmental Modelling and Software

Integrated Assessment Modelling (IAM) incorporates knowledge from different disciplines to provide an overarching assessment of the impact of different management decisions. Integrated models generally require numerous parameters from varying sources, many not known with certainty. Rapid increases in model size and complexity, particularly in the case of integrated models for decision-making, pose new challenges for effective sensitivity analysis. Some of the identified shortcomings of existing sensitivity analysis methods in the context of IAM include: computational inefficiency, failure to assess parameter interactions, excessive data requirements (e.g. requiring parameter probability distributions), assumptions of model linearity and monotonicity and, in particular, difficulty of …

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Intelligent Configuration Of Numerical Solvers Of Environmental Ode/Dae Models Using Machine Learning Techniques, Petra Claeys, Peter A. Vanrolleghem Jul 2006

Intelligent Configuration Of Numerical Solvers Of Environmental Ode/Dae Models Using Machine Learning Techniques, Petra Claeys, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

The models considered in this work contain combinations of a large number of non-linear differential equations and algebraic equations, which have to be solved numerically. Because of this, running simulation experiments on a computer can be very time-consuming, i.e. it can last for days or even weeks. On top of that, some solvers are not appropriate for solving certain of these systems. For example, stiff solvers are only appropriate for stiff systems while they are not the best choice for non-stiff systems. Choosing the appropriate solver and solver settings for a certain initialized model can significantly shorten the computation time. …

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Tornado: A Versatile And Efficient Modelling And Virtual Experimentation Kernel For Water Quality Systems, Filip Claeys, Dirk J. W. De Pauw, Lorenzo Benedetti, Ingmar Nopens, Peter A. Vanrolleghem Jul 2006

Tornado: A Versatile And Efficient Modelling And Virtual Experimentation Kernel For Water Quality Systems, Filip Claeys, Dirk J. W. De Pauw, Lorenzo Benedetti, Ingmar Nopens, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

Recently, a new kernel for modelling and virtual experimentation (i.e. any evaluation of a model) in the domain of water quality management was developed. This kernel was named “Tornado” and will be included in the new generation of the WEST product family, as well as in several other products (e.g. DHI’s MOUSE-TRAP) and projects. Most important issues during development were versatility and efficiency. This paper focuses mainly on the rationale for the new development, and the major features of the resulting kernel. It is argued that classical approaches (such as the adoption of MATLAB/SIMULINK, custom FORTRAN codes and/or domain-specific simulators) …

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Deriving A Spatially-Explicit Hillslope Sediment Delivery Ratio Model Based On The Travel Time Of Water Across A Hillslope, D. A. Post, A. E. Kinsey-Henderson, R. Bartley, A. Hawdon Jul 2006

Deriving A Spatially-Explicit Hillslope Sediment Delivery Ratio Model Based On The Travel Time Of Water Across A Hillslope, D. A. Post, A. E. Kinsey-Henderson, R. Bartley, A. Hawdon

International Congress on Environmental Modelling and Software

To derive a sediment budget at the catchment scale, sediment transport models such as SedNet typically require an estimate to be made of the input of sediment to each stream link for each defined sub-catchment. This requires an estimate of both the erosion and delivery of sediment from every pixel within each sub-catchment. The total erosion within each pixel is calculated using the Universal Soil Loss Equation (USLE), while the delivery of sediment from that pixel to the nearest stream is based on a hillslope delivery ratio (HSDR). At large scales (250 m), a constant HSDR is typically used, however …

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Confronting Edss-Maintenance Validation, Clàudia Turon, Joaquim Comas, Ulises Cortés, Manel Poch Jul 2006

Confronting Edss-Maintenance Validation, Clàudia Turon, Joaquim Comas, Ulises Cortés, Manel Poch

International Congress on Environmental Modelling and Software

Daily operation and maintenance tasks are needed to guarantee the correct performance of Constructed Wetlands (CWs). The definition of these activities is a complex task since these actions vary according to the technology, the configuration and the design of the wastewater treatment plant, the community characteristics and the features of the receiving media. To support the definition of these actions an Environmental Decision Support System (EDSS) has been constructed (EDSS-maintenance). The methodology used to develop EDSS-maintenance is based on the following 5 steps: environmental problem analysis, data and knowledge acquisition, model selection, model implementation and validation. The first 4 steps …

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