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Data-Driven Rainfall/Runoff Modelling Based On A Neuro-Fuzzy Inferential System, N. Bartoletti, F. Casagli, S. Marsili-Libelli, A. Nardi, A. Oliva, L. Palandri Jul 2016

Data-Driven Rainfall/Runoff Modelling Based On A Neuro-Fuzzy Inferential System, N. Bartoletti, F. Casagli, S. Marsili-Libelli, A. Nardi, A. Oliva, L. Palandri

International Congress on Environmental Modelling and Software

The development of rainfall/runoff models may involve extensive computation and differing platforms, including GIS. In this paper we present a simple data-driven approach which avoids the use of GIS, but is based on a combination of Principal Component Analysis (PCA) and an Adaptive Neuro Fuzzy Inference System (ANFIS) to produce a simple and effective output flow prediction based on previous rainfall/runoff data. Given the ANFIS internal complexity, the emphasis of the paper is on how to set-up the most representative and parsimonious data structure that produces an efficient output flow estimation. In the preliminary data reduction stage, the PCA approach …

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Planning Complex Agro-Ecosystems: The Case Of Analog Forestry, F. Recanati, Giorgio Guariso, M. Saini, Sergio Vilchez Mendoza Jul 2016

Planning Complex Agro-Ecosystems: The Case Of Analog Forestry, F. Recanati, Giorgio Guariso, M. Saini, Sergio Vilchez Mendoza

International Congress on Environmental Modelling and Software

Traditional agroecosystems, aimed at maximizing the short term productivity, are characterized by oversimplification of ecological structure and dependence on the use of external inputs. Moreover, intensive agriculture is one of the main cause of deforestation. The main consequence of traditional agriculture is the loss of natural ecosystems and of their precious services. Analog forestry has emerged as a sustainable productive model able to be integrated in forest contexts, without degrading their ecological functions. The obtained agro-ecosystem is characterized by an ecological structure similar to the one of forest, and by the presence of several productive species in the same area. …

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A Mathematical Procedure To Estimate Variations Between Grain-Size Distributions, Laura Calcagni, Bianca Di Lorenzo, Rossella Di Mento, Ornella Nonnis, Anna Maria Cicero Jul 2016

A Mathematical Procedure To Estimate Variations Between Grain-Size Distributions, Laura Calcagni, Bianca Di Lorenzo, Rossella Di Mento, Ornella Nonnis, Anna Maria Cicero

International Congress on Environmental Modelling and Software

Grain-size is the most fundamental property of sediment particles, its analysis is essential to understand sediment provenance, transport history and depositional conditions. In the ambit of environmental monitoring a key point is often the study of the variations of sediments composition in terms of variation of their grain-size distributions. In this work it is presented a procedure based on the computing of easy mathematical indexes useful to perform in an effective way the comparison of grain-size distributions. The developed procedure consists in two steps of analysis to quantify the dissimilarities between grain-size distributions and to characterize the typology of occurred …

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Modeling Herding Behavior On Financial Markets Affected By Exogenous Climate-Related Shocks, Dmitry V. Kovalevsky Jul 2016

Modeling Herding Behavior On Financial Markets Affected By Exogenous Climate-Related Shocks, Dmitry V. Kovalevsky

International Congress on Environmental Modelling and Software

In many economic models (including many models from economics of climate change) the agents make decisions solely on the basis of ‘objective’ information (e.g., the market price level). However, a number of alternative modeling frameworks have been developed, where individual economic agents, when making decisions, take into account the observed behavior of other economic agents. One of pioneering contributions to this research area was the Kirman’s ‘ant model’ (Kirman, 1993). While initially the model was applied to describing the collective behavior of social insects (ants), later it was extensively used for describing the ‘herding behavior’ in economic systems. Particularly, ‘herding …

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Modelling For Reproducibility, Transparency, And Continuous Learning: Revisiting Jakeman’S 10 Steps, Thorsten Arnold Jul 2016

Modelling For Reproducibility, Transparency, And Continuous Learning: Revisiting Jakeman’S 10 Steps, Thorsten Arnold

International Congress on Environmental Modelling and Software

Numerical modelling has become the standard tool to evaluate vast amounts of data, both for the public management of natural resources by government agencies and to understand environmental interactions within academia. While an ever-increasing amount of software tools is being developed and approaches are formulated how modellers should interact with stakeholders, the modelling community has not yet addressed criteria how these tools and approaches are applied cost effectively. Across the board, public agencies and academia continue to experience budget and time overruns that are systematic and need to be addressed if environmental modelling shall provide the benefits that modellers claim. …

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From Climate Change Awareness To Energy Efficient Behaviour, Leila Niamir, Tatiana Filatova Jul 2016

From Climate Change Awareness To Energy Efficient Behaviour, Leila Niamir, Tatiana Filatova

International Congress on Environmental Modelling and Software

Understanding and predicting how climate will change, and whether and how a transition to low-carbon economies will develop over the next century is of vital importance. Nowadays there is high competition between countries to achieve a low-carbon economy. They are examining different ways e.g. different energy efficient technologies and low-carbon energy sources, however they believe that human choices and behavioural change has a crucial impact, which is many times discussed in the literature as well. In this paper, we aim to discuss challenges related to modelling behavioural changes on the demand side and show effect of the demand side activation …

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Assessing Input-Output Relations In Environmental Data By Means Of Fuzzy Clustering And Bayesian Inference, L. Bigozzi, E. El Basri, F. Ianniciello, S. Marsili-Libelli, I. Simonetti Jul 2016

Assessing Input-Output Relations In Environmental Data By Means Of Fuzzy Clustering And Bayesian Inference, L. Bigozzi, E. El Basri, F. Ianniciello, S. Marsili-Libelli, I. Simonetti

International Congress on Environmental Modelling and Software

When dealing with complex environmental datasets, it is also difficult to establish the strength of the input-output relation among variables. Correlation analysis may yield a preliminary indication, but is limited to the linear case. Mutual Information (MI) is a more powerful method which can establish input-output dependence regardless of the nature of their interaction. However, to avoid the heavy computational demand of MI, a simple method is presented based on fuzzy clustering and Bayes’ rule. After a preliminary conditioning phase, the data are grouped by fuzzy clustering and approximated with the value of the most relevant centroid. Then the prior …

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Randomness Representation In Turbulent Flows With Bed Roughness Elements Using The Spectrum Of The Kolmogorov Complexity, D. T. Mihailović, G. Mimić, P. Gualtieri, I. Arsenić, C. Gualtieri Jul 2016

Randomness Representation In Turbulent Flows With Bed Roughness Elements Using The Spectrum Of The Kolmogorov Complexity, D. T. Mihailović, G. Mimić, P. Gualtieri, I. Arsenić, C. Gualtieri

International Congress on Environmental Modelling and Software

One feature of turbulent flow in relation to randomness is quantified. Experimental data from a turbulent flow collected in a laboratory channel with bed roughness elements of different densities are used. An analysis based on a classical turbulence statistics is performed, using a simple empirical model for estimating the relative sizes of mixing lengths representing the typical scale of an eddy in the corresponding surface layer, to describe the turbulence in terms of irregular or random flow. Instead of such description a quantification of the turbulence flow using measures based on the spectrum of the Kolmogorov complexity (KC) is proposed.

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Modelling Socio-Ecological Problems With Delay. Case Study On Environmental Damage, Veronika Novotná, Bedřich Půža, Jiří Hřebíček Jul 2016

Modelling Socio-Ecological Problems With Delay. Case Study On Environmental Damage, Veronika Novotná, Bedřich Půža, Jiří Hřebíček

International Congress on Environmental Modelling and Software

The paper presents modelling complex socio-ecological problems, where relations among individual quantities vary in time. This includes dynamics of processes in the model, which enables to understand time as a continuous quantity and to describe dynamic processes by a system of differential equations with delay. Implementation of these models in Maple system enables both analytic and numerical solutions and their visualizations. The Maple solution of the specific example of the model with delayed argument is shown, where all input parameters can be interactively changed during the solution process, i.e. delay, interval of the solution, or other parameters which have an …

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Study On The Buoyancy Plume Model Coupling With The Effects Of Temperature, Salinity And Sediment, Shen Zia, Huang Juping, Yan Zhongluan, Li Ran, Feng Jingjie Jul 2016

Study On The Buoyancy Plume Model Coupling With The Effects Of Temperature, Salinity And Sediment, Shen Zia, Huang Juping, Yan Zhongluan, Li Ran, Feng Jingjie

International Congress on Environmental Modelling and Software

The paper developed a three-dimensional model for buoyancy plume coupling with the comprehensive effects of different temperature, sediment and salinity. The model includes mass continuity equation, momentum equation and energy equation, state equation, Renormalization Group (RNG) κ-ε turbulence transport equation, sediment scour equation, salinity advection equation. The discretization scheme of Finite Difference Method (FDM) is used to solve Reynolds-Averaged Navier-Stokes (RANS) equation, combining the discretization method of the central difference scheme and the upwind scheme. A method called Generalized Minimal Residual Algorithm (GMRES) is used to solve velocity-pressure term of discrete equation. The volume of fluid (VOF) method is adopted …

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Spatial And Dynamic Sensitivity Analysis Of A Biophysical Model Of Nitrogen Transfers And Transformations At The Landscape Scale., Jordi Ferrer Saval, Pierre Barbillon, Cyril Benhamou, Patrick Durand, Marie-Luce Taupin, Hervé Monod, Jean-Louis Drouet Jul 2016

Spatial And Dynamic Sensitivity Analysis Of A Biophysical Model Of Nitrogen Transfers And Transformations At The Landscape Scale., Jordi Ferrer Saval, Pierre Barbillon, Cyril Benhamou, Patrick Durand, Marie-Luce Taupin, Hervé Monod, Jean-Louis Drouet

International Congress on Environmental Modelling and Software

Modelling complex systems such as agroecosystems often requires the quantification of a large number of input factors. Sensitivity analyses are useful to fix the appropriate spatial and temporal resolution of models and to reduce the number of input factors to be measured or estimated accurately. Comprehensive spatial and dynamic sensitivity analyses were applied to the Nitroscape model, a deterministic spatially distributed model describing nitrogen transfers and transformations in a rural landscape. Simulations were led on a virtual landscape that represented five years of farm management in an intensive rural area of 3 km². Cluster analyses were applied to summarize the …

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Analyzing Regime Shifts In Agent-Based Models With Equation-Free Analysis, Romina Martin, Spencer Angus Thomas Jul 2016

Analyzing Regime Shifts In Agent-Based Models With Equation-Free Analysis, Romina Martin, Spencer Angus Thomas

International Congress on Environmental Modelling and Software

Conventional tools to analyze regime shifts in ecosystems, e.g. stable state and bifurcation analyses, are increasingly adapted to investigate social-ecological systems. The challenge lies in combining the analysis of system dynamics with the analysis of transient dynamics emerging from adaptive and heterogeneous agents. A typical question is, to which extent do micro level interactions contribute to a macro level outcome? We demonstrate the application of a new tool, equation-free analysis, for evaluating the state space from an agent-based model (ABM) on lake restoration. By sidestepping the requirement of an equation describing a systems macroscopic behavior, equation free analysis enables system …

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Numerical Simulation Of A New Three-Dimensional Non-Hydrostatic Model, Ling Kang, Shangwen Jiang Jul 2016

Numerical Simulation Of A New Three-Dimensional Non-Hydrostatic Model, Ling Kang, Shangwen Jiang

International Congress on Environmental Modelling and Software

The hydrostatic pressure assumption has been widely applied in hydrodynamic numerical simulation in rivers and lakes, but it has been found inappropriate in various cases where the vertical acceleration is significant. To this end, this paper proposes a new three-dimensional, non-hydrostatic hydrodynamic model. Based on Navier-Stokes equations with the σ-coordinate transformation, rectangular grid is adopted as the approximation of the study region. For numerical solution, the process includes two steps, the estimated step and the modified step. The FDM is adopted to derive the discretization of the governing equations, and the θ method is employed for equations solution. A numerical …

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Implication Of Density-Dependent Flow On Numerical Modelling Of Sw-Gw Interactions, Sina Alaghmand, Philip Brunner, Thomas Graf, Craig Simmons Jul 2016

Implication Of Density-Dependent Flow On Numerical Modelling Of Sw-Gw Interactions, Sina Alaghmand, Philip Brunner, Thomas Graf, Craig Simmons

International Congress on Environmental Modelling and Software

With the growing interest in the last decades in the modelling of hydrogeological processes involved in the water resources management, it has been recognized that the assumption of constant-properties water is no longer adequate in the analysis and simulation of the flow considered in these cases. In recent years, many studies used simplistic approaches that may not represent the aquifer flow dynamics realistically by not accounting for changing fluid density. This study explore the importance of understanding the impact of density-dependent flow on SW-GW interactions. To this aim two synthetic models was developed at large and small scales and various …

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Improving Multi-Objective Management Of Water Quality Tipping Points: Revisiting The Classical Shallow Lake Problem, Julianne Quinn, Patrick Reed, Klaus Keller Jul 2016

Improving Multi-Objective Management Of Water Quality Tipping Points: Revisiting The Classical Shallow Lake Problem, Julianne Quinn, Patrick Reed, Klaus Keller

International Congress on Environmental Modelling and Software

Recent multi-objective extensions of the classical shallow lake problem are useful for exploring the conceptual and computational challenges that emerge when managing irreversible water quality tipping points. Building on this work, we explore a four objective version of the lake problem where a hypothetical town derives economic benefits from polluting a nearby lake, but at the risk of irreversibly tipping the lake into a permanently polluted state. The trophic state of the lake exhibits non-linear threshold dynamics; below some critical phosphorus (P) threshold it is healthy and oligotrophic, but above this threshold it is irreversibly eutrophic. The town must decide …

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The Delayed Oscillator Model For Climate Variability: A Review And An Application To The Atlantic Meridional Mode, F. Mesmin Awo, Gaël Alory, Ezinvi Baloïtcha Jul 2016

The Delayed Oscillator Model For Climate Variability: A Review And An Application To The Atlantic Meridional Mode, F. Mesmin Awo, Gaël Alory, Ezinvi Baloïtcha

International Congress on Environmental Modelling and Software

Understanding climate variability in the tropical Pacific and Atlantic oceans is a considerable challenge for climate scientists. Interannual to decadal climate variability is dominated in these regions by the El Niño-Southern Oscillation (ENSO), the North Atlantic Oscillation, the tropical Atlantic zonal and meridional modes. These climatic modes are mainly driven by competing positive and negative feedback processes that involve ocean-atmosphere interactions. The delayed oscillator, a conceptual model that include these processes, has been developed to explain the cyclic nature of ENSO in the Pacific Ocean. We review its successful applications in the Atlantic Ocean and present our own application of …

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Global Monitoring Plan Data Warehouse As A Tool For Worldwide Assessment Of Persistent Organic Pollution, Jiří Kalina, Jiří Hřebíček, Richard Hůlek, Jana Borůvková, Jana Klánová Jul 2016

Global Monitoring Plan Data Warehouse As A Tool For Worldwide Assessment Of Persistent Organic Pollution, Jiří Kalina, Jiří Hřebíček, Richard Hůlek, Jana Borůvková, Jana Klánová

International Congress on Environmental Modelling and Software

In 2004 the Stockholm Convention came into force, which eliminates a manufacture and use of persistent organic pollutants. Global Monitoring Plan is an important executive component of the convention, providing framework for an evaluation of its effectiveness. It ensures collection of comparable monitoring data on POPs from around the world in order to identify changes in POPs concentrations over time and their eventual transport. There are several programs focused on a monitoring of persistent organic pollutants in diverse environmental matrices over the globe, each working with a different methodology of sampling and analyses. Results of these programs are reported in …

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Investigating The Street Canyon Vegetation Effects Using The Moment Method, Viktor Šíp, Luděk Beneš Jul 2016

Investigating The Street Canyon Vegetation Effects Using The Moment Method, Viktor Šíp, Luděk Beneš

International Congress on Environmental Modelling and Software

In this paper we investigate the effects of the vegetation inside a street canyon. Flow through and around the standalone street canyon is calculated using a CFD solver based on the Reynoldsaveraged Navier-Stokes equations. The dispersion of the pollutant is computed using the moment method that models the behaviour of the particle size distribution. Resulting pollutant concentrations for several wind conditions and for configurations without and with the trees are compared to the wind tunnel measurements. Using the deposition velocity model for the moment method, the effect of the dry deposition on the vegetation is then assessed. Three modes of …

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From Raw Material To Biofuel Demand: The Agraf Model, Coline Assaiante, Pierre-Alain Jayet, Frédérick Lantz Jul 2016

From Raw Material To Biofuel Demand: The Agraf Model, Coline Assaiante, Pierre-Alain Jayet, Frédérick Lantz

International Congress on Environmental Modelling and Software

The search for energetic independence, for boosting local economies and for reducing polluting emissions, has supported bioenergy’s development and biofuels in particular. Mandatory biofuels incorporation rates have been recently established in several countries, including the European Union, in order to promote the use of renewable energetic resources in spite of several criticisms toward biofuels relating to their impacts on food security, the environment and the conflicts associated with resource allocations. To study existing concerns on the growth, the profitability, the limiting factors biofuels, as well as the impacts of current policies in force, a highly parameterized operational modelling tool (AGRAF) …

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Constraint Programming Versus Mip For Lca-Based Multi-Objective Optimization Of Sustainable Potable Water Production Plants, Florin Capitanescu, Antonino Marvuglia, Enrico Benetto, Aras Ahmadi, Ligia Tiruta-Barna Jul 2016

Constraint Programming Versus Mip For Lca-Based Multi-Objective Optimization Of Sustainable Potable Water Production Plants, Florin Capitanescu, Antonino Marvuglia, Enrico Benetto, Aras Ahmadi, Ligia Tiruta-Barna

International Congress on Environmental Modelling and Software

Many real-world multi-objective optimization (MOO) problems rely on computationally expensive simulators of industrial processes and require solutions within a limited time budget. In this context, we propose a heuristic approach which aims at building a surrogate problem model, solvable by computationally efficient optimization methods, in order to quickly provide a sufficiently accurate estimation of the Pareto front. The proposed approach generates a multi-objective mixed-integer programming (MO-MIP) proxy model of the MOO problem using sensitivity-based piece-wise linear approximation of objectives and constraints. The approximation of the Pareto front is obtained by applying the ε-constraint method to the multi-objective surrogate problem, …

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Time Series Analyst: Interactive Online Visualization Of Standards Based Environmental Time Series Data, Jeffery S. Horsburgh, Amber Spackman Jones, Maurier Ramírez, Juan Caraballo Jul 2016

Time Series Analyst: Interactive Online Visualization Of Standards Based Environmental Time Series Data, Jeffery S. Horsburgh, Amber Spackman Jones, Maurier Ramírez, Juan Caraballo

International Congress on Environmental Modelling and Software

Visualization is a common need of many researchers, organizations, and projects that collect and use environmental sensor data. Web-based tools can provide screening-level visualization and data analysis functionality for users with a range of technical expertise. However, it is difficult to integrate data from multiple sources due to syntactic and semantic differences in data formats and different data delivery mechanisms that are not always interoperable. We developed an open-source time series visualization tool called the Time Series Analyst (TSA) that integrates data from multiple sources using web service interfaces and a standardized data encoding format. The TSA provides multiple types …

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Number Of Patterns In Lempel-Ziv Algorithm Applied To Iterative Maps And Measured Time Series, G. Mimić, I. Arsenić, D. T. Mihailović Jul 2016

Number Of Patterns In Lempel-Ziv Algorithm Applied To Iterative Maps And Measured Time Series, G. Mimić, I. Arsenić, D. T. Mihailović

International Congress on Environmental Modelling and Software

Some tests with information measure based on Kolmogorov complexity, using Lempel-Ziv algorithm, were performed. Information measure, which indicates randomness, was applied on the modeled and measured time series. The logistic map iterations were used as the modeled time series and the measurements of velocity data from the turbulent flow collected in a laboratory channel, were used as the measured one. The complexity counter, indicating the number of distinct patterns in the time series, was computed. An analysis has shown that the number of patterns in the measured time series is increasing with the time series length, but having a saturation …

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Desired Precision In Multi-Objective Optimization: Epsilon Archiving Or Rounding Objectives?, Masoud Asadzadeh Jul 2016

Desired Precision In Multi-Objective Optimization: Epsilon Archiving Or Rounding Objectives?, Masoud Asadzadeh

International Congress on Environmental Modelling and Software

Multi-objective optimization (MO) aids in supporting the decision making process in environmental engineering and design problems. One of the main goals of solving a MO problem is to archive a set of solutions that are well-distributed across a wide range of all the design objectives. To this end, some of the state-of-the-art MO algorithms use the epsilon dominance concept to define a mesh-grid with pre-defined grid-cell size (often called epsilon) in the objective space and archive at most one solution in each grid-cell. Moreover, epsilon archiving helps the MO algorithm control the number of archived solutions. This is particularly important …

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An Experimental Comparison Of Methods To Handle Missing Values In Environmental Datasets, A. D. Maldonado, P. A. Aguilera, A. Salmeron Jul 2016

An Experimental Comparison Of Methods To Handle Missing Values In Environmental Datasets, A. D. Maldonado, P. A. Aguilera, A. Salmeron

International Congress on Environmental Modelling and Software

This paper reports on a comparison of different techniques to handle missing data in a real environmental dataset containing missing values. In particular, we handled a dataset related to a surface water quality index. The chosen techniques were regression imputation by linear regression, a model tree and a Bayesian network; multiple imputation by chained equations; and data augmentation by a Bayesian network. The models were tested by analyzing the predictive maps and by comparing the density function of the predicted variable with the observed one. The experimental results showed that the imputation by linear regression and the multiple imputation by …

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On The Use Of Finite-Difference Model To Evaluate The Impact Of Underground Water Overexploitation, Hani A., Bougherira N., Djabri L., Chaffai H., Lallahem S. Jul 2016

On The Use Of Finite-Difference Model To Evaluate The Impact Of Underground Water Overexploitation, Hani A., Bougherira N., Djabri L., Chaffai H., Lallahem S.

International Congress on Environmental Modelling and Software

The potentiometric surface in the Annaba basin, which covers an area of 264 km2, has declined significantly since 1995. A transient multilayer model has been developed to synthesise the hydrologic data. The groundwater flow was modelled using the finite difference method with a horizontal dimension of 500 x 500 m for the cells. The model consists of two layers, the first corresponding to the alluvial phreatic aquifer and the second to the deep confined aquifer, and is calibrated against the steady state groundwater heads recorded before 1996. Under steady-state conditions, the correspondence between simulated and observed water levels …

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Decision Support System For Waste Management, Jiří Hřebíček, Jiří Kalina, Jana Soukopová, Jiří Valta, Jan Prášek Jul 2016

Decision Support System For Waste Management, Jiří Hřebíček, Jiří Kalina, Jana Soukopová, Jiří Valta, Jan Prášek

International Congress on Environmental Modelling and Software

The paper presents a prototype of the integrated decision support system DECWASTE developed to support decision making in waste management in the Czech Republic. It uses linked open data of eGovernment systems of the Czech Republic. It consists of six sub-modules: PARSER, which downloads the appropriate data from the eGovernment systems to its databases; PREVENT, which calculates the prevention impact on waste generation; FORECAST, which forecasts waste generation for a given time period using developed mathematical forecast models based on the DPSIR (Driving forces-Pressures-States-Impacts-Responses) framework including past time series of waste stream generation; TREATMENT, which forecasts waste treatment for the …

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Integration Of Land Use And Land Cover Models: Coupling Two Existing Models To Improve The Simulation Of Location Choice, Harutyun Shahumyana, Rolf Moeckel, Peter Claggett, Frederick Ducca Jul 2016

Integration Of Land Use And Land Cover Models: Coupling Two Existing Models To Improve The Simulation Of Location Choice, Harutyun Shahumyana, Rolf Moeckel, Peter Claggett, Frederick Ducca

International Congress on Environmental Modelling and Software

Single models do not usually provide all answers required for complex policy decisions, so an integrated modelling is often applied to inform policy makers and urban planners. Developing a fully integrated model is an expensive and time consuming task, thus, coupling existing models is often used for model integration. The paper provides an overview of potential model integration approaches, briefly describes the Simple Integrated Land Use Orchestrator (SILO) model and the Chesapeake Bay Land Change Model (CBLCM), and focuses on the integration method applied to link those models. Particularly, Python wrappers were developed to loosely couple SILO and CBLCM; while …

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Simulation Of Guozheng Lake Temperature By Using A New Water Temperature Model, Ling Kang, Zheng Jing Jul 2016

Simulation Of Guozheng Lake Temperature By Using A New Water Temperature Model, Ling Kang, Zheng Jing

International Congress on Environmental Modelling and Software

Water temperature in lakes plays an important role in aquatic ecosystem. Wind sheltering effect has an important influence on water temperature distribution. An improved wind sheltering model, which was developed to quantify wind sheltering effect, was coupled to vertical one dimensional heat conduction model to create a new water temperature model. Based on the relationship between the wind direction and obstacle location, as well as the characteristics of wind variation downwind from the obstacle, the wind sheltering model could calculate a time-dependent wind sheltering coefficient. For numerical solution, a new operator-splitting method was adopted. To compensate for the deviation caused …

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Multispecies Granular Biofilm Modelling For Simultaneous Anammox And Denitrification Processes In Batch Systems, Mohammad Azari, Manfred Lȕbken, Martin Denecke Jul 2016

Multispecies Granular Biofilm Modelling For Simultaneous Anammox And Denitrification Processes In Batch Systems, Mohammad Azari, Manfred Lȕbken, Martin Denecke

International Congress on Environmental Modelling and Software

The nitrogen removal pathways in anaerobic ammonium oxidation (anammox) process where anaerobic ammonium-oxidizing bacteria and denitrifying heterotrophs convert ammonium and nitrite directly to dinitrogen gas under anoxic conditions were investigated using a mathematical model. The Activated Sludge Model No. 1 (ASM1) was modified with two step denitrification and one-step anaerobic ammonia oxidation. A one dimensional granular biofilm model was implemented in Aquasim 2.1v (EAWAG, Switzerland) in order to describe a series of batch processes operated in a bioreactor treating synthetic wastewater. A sophisticated statistical method was used for parameter estimation. The model was not sensitive with respect to the detachment …

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Evidence Of Contaminant Storage At The Soil/Vadose Zone Interface And Implication For Nitrate Residence Time Modeling In Groundwaters, E. Viel, M. Dedewanou, Yves Coquet, S. Binet Jul 2016

Evidence Of Contaminant Storage At The Soil/Vadose Zone Interface And Implication For Nitrate Residence Time Modeling In Groundwaters, E. Viel, M. Dedewanou, Yves Coquet, S. Binet

International Congress on Environmental Modelling and Software

The “Beauce” limestone aquifer is contaminated by nitrate and pesticides mostly coming from agricultural activities. In this region the vadose zone can extend to more than 20 m in depth, appears to be highly heterogeneous and plays a significant role in the retention and/or release of pollutants to aquifers and wells. In order to gain insight into contaminant transfer in the vadose zone, tracer experiments were conducted in a pit, 4 meters wide, 1.6 meters deep, using (1) 30 L of brilliant blue (BB) at a concentration of 6 g/L to map the preferential flow along the percolation profile and …

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