Digital Commons Network^™

Hecke Eigenvalues And Arithmetic Cohomology, William Leonard Cocke

Theses and Dissertations

We provide algorithms and documention to compute the cohomology of congruence subgroups of the special linear group over the integers when n=3 using the well-rounded retract and the Voronoi decomposition. We define the Sharbly complex and how one acts on a k-sharbly by the Hecke operators. Since the norm of a sharbly is not preserved by the Hecke operators we also examine the reduction techniques described by Gunnells and present our implementation of said techniques for n=3.

An R Package For Implementing Multiple Evapotranspiration Formulations, Danlu Guo, Seth Westra, Holger R. Maier

International Congress on Environmental Modelling and Software

The use of multiple evapotranspiration (ET) models is critical for exploring the ambiguity in the representations of ET processes. Although ensemble ET models are increasingly used to address this ambiguity, practical issues include: 1) the diversity of process representations, which require different input data and constants; 2) the diversity of nomenclature, terminology and units used in the literature; and 3) the complexity of some formulations, requiring significant time for coding and leading to potential user errors. We describe an R package that estimates both actual and potential ET from 17 well-known formulations. Results are presented as summary text and plots, …

Rethinking Riverine Habitat Quality: Integrated Systems Modeling To Improve Watershed Habitat Management And Decision Making, Avman H. Alafifi, David E. Rosenberg

International Congress on Environmental Modelling and Software

River restoration and conservation projects use habitat quality indicators (e.g., Habitat Suitability Index) to monitor and quantify changes of one or a few habitat attributes (e.g. instream flow, bank stability, and flood regime). A more integrated approach representing broader watershed habitat components requires rethinking riverine habitat quality. Systems models provide decision makers with tools to quantify and understand interconnections between different habitat components. They help predict and account for potential changes in hydrologic, ecological, and management variables in water systems. Applying systems models in restoration practice requires developing and applying new and robust habitat quality indicators that capture dynamic hydrologic …

Modelling Similarities Of Endocrine Disruptors In Pine Needles And Human Breast Milk, Kristina Voigt, Rainer Bruggemann, Hagen Scherb, Ismet Cok, Karl-Werner Schramm

International Congress on Environmental Modelling and Software

In a recently performed monitoring project, 18 OCPs (Organochlorine pesticides) in paired samples of pine needles and human breast milk samples were analysed in different regions in the Taurus Mountains in Turkey. The aim of our data evaluation approach is to find out whether there are conformities between the paired human breast milk and pine needle samples. An appropriate data analysis method to identify such conformities and differences is the discrete mathematical method named Hasse diagram technique. The software package used is the PyHasse software. It comprises several modules, which are of great support in the evaluation of environmental data. …

Developing An Aquasim Biofilm Model To Simulate A Novel Batch Biofilm Passive Aeration Technology, Noelle Jones, Maebh Grace, Eoghan Clifford

International Congress on Environmental Modelling and Software

Mathematical modelling of biofilm reactors can be complicated and time-consuming due to the complexity of the biofilms and a wide range of models have been developed to simulate biofilm reactors.

The Pumped Flow Biofilm Reactor (PFBR) is a new biofilm-based passive aeration system (PAS) that is an example of a complex biofilm system. The PFBR is a two reactor technology that employs a unique hydraulic regime and enables aerobic, anoxic and anaerobic conditions to be sequenced . Biofilm, growing on plastic media modules within the two reactors, is aerated passively as wastewater is moved alternately between the reactors during an …

Modeling And Implementation Of A Geospatial Database For Environmental Niches And Potential Geographic Distributions, Gerardo José Zárate, Jugurta Lisboa-Filho, Carlos Frankl Sperber, Flavia Maria Da Silva Carmo

International Congress on Environmental Modelling and Software

The ecological niche of a species is defined by an array of biotic and abiotic requirements that allow organisms to live and reproduce in a geographic region. Abiotic data from the ecological niche in combination with occurrence data can be used to predict the potential geographic distribution of a species in different regions. Potential geographic distributions are useful in predicting the extent of invasive species, predict distributions as preparation for climate change and find appropriate regions for endangered species, among others. Geographic entities and environmental variables can be represented with a high-level abstraction in diagrams using formalism dedicated to model …

Eliciting Stakeholder Preferences Through Nonmarket Valuation Techniques, Marit E. Kragt

International Congress on Environmental Modelling and Software

To successfully predict the impacts of environmental change, modellers need to incorporate analyses of human behaviour into their predictions. The engagement of stakeholders, including participatory model development, is now widely advocated as an approach to account for stakeholder preferences. While participatory approaches are suitable to involve targeted stakeholder groups and technical experts, it is typically prohibitively expensive to engage a wide range of communities in the model development process. Many environmental modellers may be aware of social science research methods to participatory research. Socio-economic approaches to elicit stakeholder preferences are, however, less commonly used. This paper presents three stated preference …

A Social Metamodel To Control The Participatory Process In Complex System Modelling, Michel Lample, Denis Bailly, Johanna Ballé-Béganton

International Congress on Environmental Modelling and Software

The metamodel framework is a new tool for co-construction of models involving societal or political participation. Rather than an attempt to model the social factor by numerical techniques which amounts to project the social paradigm in the model paradigm, the metamodel framework provides a way to overcome the difficulties of social behaviour by an inverse projection of the model paradigm into the social one. The framework asks for a strict methodology based on a suitable agenda, a quality process and the management by an Architect team. Furthermore, this framework accommodates lean modelling techniques that system platforms are able to provide.

Business Intelligence In Environmental Reporting Powered By Xbrl, Jiří Hřebíček, Michal Hodinka, Michael Ŝtencl, Oldřich Trenz

International Congress on Environmental Modelling and Software

The paper discusses several critical points of the whole concept of Business lntelligence (Bl) approach to environmental reporting powered by XBRL. First, and most important, is the usage of structured data delivered via XBRL. The main profit on usage of XBRL is the optimization of the Extract, Transform and Load (ETL) process and its combination commonly used best practices on data warehouse models. The whole Bl workflow could be moved further by additional data quality health checks, extended mathematical and logical data test, basics of data discovery and drill-down techniques. The state of the art on the XBRL level and …

Where Are We In Wastewater Treatment Plants Data Management? A Review And A Proposal, Manel Poch, Joaquim Comas, José Porro, Manel Garrido-Baserba, Lluis Corominas, Maite Pijuan

International Congress on Environmental Modelling and Software

Wastewater treatment plants (WWTP) are comprised of complex processes that need to be optimally managed. To attain that, in the last years an impressive effort has been made to incorporate monitoring devices able to provide from several hundred to more than ten thousand signals. With the aim to take benefit of those data, different data mining techniques have been applied to transform them into information and knowledge in order to help WWTP's managers. Furthermore, several mathematical models have been developed intending to simulate process behaviour including biomass and pollutants transformation. However, it is recognized that this it is not enough …

The Use Of Object-Oriented Programming Concepts For Documenting A Model Ensemble, Georgii A. Alexandrov

International Congress on Environmental Modelling and Software

The spread of cloud computing services gives community modelling a reasonable opportunity to become a reality in scientific research. However, even if models will be deployed in clouds, and model codes will be open for re-use, there will be little progress in community modelling in the lack of consensus standards for model documentation. This paper is to discuss a conceptual framework for developing such standards. The proposed conceptual framework is based on the idea that a new model is often a modification of an old one, and hence, the similarities between the models of the same environmental process could be …

Case Study: Prognostic Model Of Czech Municipal Waste Production And Treatment, Jiří Kalina, Jiří Hřebíček, Gabriela Bulková

International Congress on Environmental Modelling and Software

The paper introduces the application of multidimensional regression methods and a mathematically applicable waste streams structure model for the development of new complex model of municipal waste management (production and treatment) of the Czech Republic. This model was developed for purposes of the Ministry of the Environment of the Czech Republic and consequently of the European Environment Agency. It can evaluate the sustainability of environmental decisions on the national level with the focus on waste management data requirements, national strategies for waste data acquisition, management and processing to support sustainability of waste management in accordance with the European waste legislation.

Discovering Comprehensible Hydrogeological Profiles In The Margarita Island's Aquifers Including Post-Processing In A Data Mining Process, Conti Dante, Gibert Karina

International Congress on Environmental Modelling and Software

Groundwater wells are one of the most important water resources in the world. Control and management of these resources are of high importance due to the implicit need of water as the main resource for life. This research focuses on a hydrogeological analysis with clustering, which is one of the most popular data mining methods, including In the classical data mining scheme, last step corresponds to the effective production of knowledge. In this paper, special focus on that part is done, by means of post-processing tools. The main goal is to discover prototypical profiles from the acquifer Pedro González in …

Graph Clustering Based On Social Network Community Detection Algorithms, Enrique Campbell, David Ayala-Cabrera, Joaquín Izquierdo, Rafael Pérez-García

International Congress on Environmental Modelling and Software

Graph network clustering has been an important field of investigation in recent years with a wide spectrum of applications, including environmental, genetic and engineering studies. There are two main types of applications; their suitability depends of the modeling context. Cases where the number of subdivisions is a priori known are tackled with different techniques than those where such number is not clearly evident. The second falls within the field of community detection, which has been broadly studied by social network scientists. Traditionally, community detection in graphs has been tackled by means of hierarchical clustering, which groups nodes based on their …

Pre-Processing Techniques Applied To Automatic Taxon Identification On Fish Otoliths, Ramon Reig-Bolaño, Pere Marti-Puig

International Congress on Environmental Modelling and Software

This paper analyzes the characteristics of a rotation-invariant Feature space to be used in a classifier of fish otoliths, it is compared to two other Feature spaces, one with raw data and another with transformed data (using the Elliptic Fourier Descriptors EFD). Otoliths are found in the inner ear of fish. Their shape can be analyzed to determine sex, age, populations and species, and thus they can provide necessary and relevant information for ecological studies. The Automatic Taxon Identifier (ATI) is used to classify fish otoliths directly from a query image and is implemented on-line in a Public Database. This …

The Value Of Seasonal Productivity Forecasting In Biodiesel Plans, Giulia Fiorese, Giorgio Guariso

International Congress on Environmental Modelling and Software

Crop productivity is commonly assumed as a deterministic function when developing agricultural plans. Actual data prove however that, even for the same soil at the same location, crop productivity can be better interpreted as a random variable due to the meteorological conditions of the specific year. For the production of biodiesel, crops are easily substitutable and the farmer can chose every year between various alternatives. Without information on the seasonal meteorology, the farmers select the crop to cultivate mainly on the basis of the expected productivity. However, changes in the meteorological situation may result in a reduction in crop profitability. …

Overcoming The Obstacles Of Motion Capture, Matthew Asanuma, Brent Adams

Journal of Undergraduate Research

Facial motion capture is used to capture the intimate and subtle motions of the facial features and apply them to a digital character’s face. Animation for the character, Davy Jones, in the Pirates of the Caribbean movies was achieved using this technique. In Overcoming the Obstacles of Motion Capture, I’ve tried to develop a relatively low-cost, yet high-performing technique suitable for a target market of students and independent artists.

Modelling Spatial Relationships Between Ecosystem Services And Agricultural Production In An Agent- Based Model, Changxing Dong, Mark Brady, Yann Clough, Ullrika Sahlin, Christoph Sahrbacher, Martin Stjernman

International Congress on Environmental Modelling and Software

The collective impacts of farmers’ land management decisions on above ground ecosystem services (ES) and their implications for agriculture are poorly understood. Managing habitat to provide ES is costly but at the same time it can support higher yields through, e.g., pollination or natural pest control. Due to the mobility of ES-providers (bees, natural enemies) farmers providing habitat might also benefit their neighbours, creating interdependencies among their decisions. Interdependencies among farmers’ land-use decisions and the flow of ES in space can be considered by integrating agent-based modelling and evidence-based ES models. Such integration requires a trade-off between the land-use details …

A Simple And Effective Approach To Global Sensitivity Analysis Based On Conditional Output Distributions, Francesca Pianosi, Thorsten Wagener

International Congress on Environmental Modelling and Software

Predictions of environmental models are affected by unavoidable and potentially large uncertainty. When models are applied to understand dominant controls of the system under study, uncertainties will reduce our ability to choose between competing hypotheses. When they are used to support decision-making, uncertainties will reduce our ability to discriminate between different management options and undermine the defensibility of the decision-making process. Global Sensitivity Analysis (GSA) provides quantitative information about the contribution to the uncertainty in the model output arising from different input factors like, for instance, model parameters, boundary conditions or forcing data. GSA thus provides insights into the model …

Activated Sludge With Total Solids Retention: Modified-Asm1 Modelling And Simulation, Cheikh Fall, Anabel Jimenez-Zarate, Ericka Millan-Lagunas, Yves Comeau

International Congress on Environmental Modelling and Software

There are many new strategies put forward for minimizing excess sludge generation in biological wastewater treatment. Some of them were developed within the context of dynamic activated sludge modelling (ASM). A number of means can be used to eliminate the traditional waste activated sludge flow and the build-up of inert solids in the aeration tanks. This includes the use of fine screens to remove the inert particulate organic fraction (X_I), hydrocyclones to lower the inorganic suspended solids (ISS), and different kinds of on-line digesters to further biodegrade the endogenous residues (X_P), via the return activated sludge …

A Model Component For Simulating The Seasonal Cycle Of Heterotrophic Respiration, G. A. Alexandrov

International Congress on Environmental Modelling and Software

Heterotrophic respiration, an important item in ecosystem carbon balance, is the process which is addressed in the global carbon cycle models and Earth system models. The seasonal cycle of the het- erotrophic respiration is determined by seasonal changes in climatic conditions and in the storage of litter (i.e., in the amount of organic substrate available as a food source for organisms composing the heterotrophic community). The model component presented in this paper is focussing at effects produced by seasonal depletion in litter storage. The seasonal changes in litter storage are modelled by ordinary differential equa- tions, which are solved analytically …

Global Sensitivity Analysis In Environmental Water Quality Modelling: Where Do We Stand?, Giorgio Mannina, Alida Cosenza, Manandraitsiory Randrianantoandro, Franҫois Anctil, Marc B. Neumann, Peter A. Vanrolleghem

International Congress on Environmental Modelling and Software

Global sensitivity analysis (GSA) is a valuable tool to support the use of mathematical models for environmental systems. During the last years the water quality modelling field has embraced the use of GSA. Environmental water quality modellers have tried to transfer the knowledge and experience acquired in other disciplines. The main objective of this paper is to provide an informed problem statement of the issues surrounding GSA applications in the environmental water quality modelling field. Specifically, this paper aims at identifying, for each GSA method, the potential use, the critical issues to be solved and the limits identified in a …

Applications Of Quantitative Microbial Risk Assessment (Qmra) To Regulatory Decision Making, Adam W. Olivieri, Edmund Y. Seto, Richard E. Danielson, Jeffrey A. Soller, Robert C. Cooper

International Congress on Environmental Modelling and Software

Intelligent risk-based decision-making requires a clear and transparent framework, and as part of that framework, includes a tractable analysis and balancing of various qualities of information from numerous sources. The purpose of this paper is to provide a number of examples on the application of QMRA, and how the information was utilized to aid and facilitate decision-making as part of the regulatory process for evaluating water recycling and municipal treatment plant discharges.

Accounting For Groups Of Animals In Qmra Of Recreational Waters, Richard W. Muirhead, Vanessa M. Cave

International Congress on Environmental Modelling and Software

The development of QMRA for recreational waters often involves assessing the inputs from multiple sources, including human sewage, agricultural sources and wild animals. The concentrations of microorganisms in faeces from individual animals are highly variable leading to a broad spectrum of risk. When modelling the load of faecal microbes from a group of animals, based on data from individuals, the group distribution must be correctly accounted for. A further complication to QMRA is that pathogen concentrations in faeces have a high proportion of non-detects making them difficult to model using standard mathematical distributions. Moreover, when only limited concentration data are …

The Qmra Wiki: A Social Media Tool For Interdisciplinary And Interagency Collaboration For Quantitative Microbial Risk Assessment, Jade Mitchell, Mark H. Weir, Wietske Van Osch, Joan Rose

International Congress on Environmental Modelling and Software

This study presents a web-based social media system that supports quantitative microbial risk assessment (QMRA) and collaboration among interdisciplinary scientists and interagency stakeholders, namely the QMRA wiki. The QMRA wiki is intended to aid the development of risk assessments by providing a collection of raw data, models and calculators as well as a platform for exchange and cross-fertilization between the QMRA community and its stakeholders. The wiki is organized around the exploration of the QMRA paradigm including the following five components: hazard identification, dose-response assessment, exposure assessment, risk characterization and risk management. Additionally, the wiki houses a number of case …

Sensitivity And Uncertainty Analysis Of A Plant-Wide Model For Carbon And Energy Footprint Of Wastewater Treatment Plants, Giorgio Mannina, Alida Cosenza, Riccardo Gori, Reza Sobhani, Manel Garrido, Diego Rosso

International Congress on Environmental Modelling and Software

This paper presents the sensitivity and uncertainty analysis of a mathematical model for Greenhouse gas (GHG) and energy consumption assessment from wastewater treatment plants (WWTPs). The model is able to simultaneously describe the main biological and physical-chemical processes in WWTP. Specifically, the mathematical model includes the main processes of the water and sludge lines influencing the methane (CH₄), nitrous oxide (N₂O), and carbon dioxide (CO₂) emissions. Further, the process energy demand and the energy recovery are also taken into account. The main objective of this paper is to analyze the key factors and sources …

App2adapt: Using Tablet Technology To Elicit Conditional Probabilities For Bayesian Belief Network Modelling, Russell Richards, Oz Sahin, Marcello Sano, Jan-Olaf Meynecke, Rachel Tiller

International Congress on Environmental Modelling and Software

The aim of this study is to use touch-screen computer tablet technology (e.g. iPAD) and its interactive flight console capabilities (e.g. touch screen 'sliders') as an improved method to stakeholder­ driven climate change adaptation research. Climate change vulnerability and adaptation have strong human dimensions meaning that the experiences of stakeholders often plays an important role when assessing adaptation options and/or the determinants of adaptive capacity. Methods such as Bayesian belief networks {BBNs) can draw upon the extensive knowledge and beliefs of stakeholders in a straightforward manner yet are underpinned by a robust mathematical framework (i.e. Bayes theory). This is critically …

Defining The Spatiotemporal Surveillance Space For Alien Species' Invasions Using Approximate Bayesian Computation, Grant Hamilton, Rune Rasmussen, Jana Mullerova, Jan Pergl, Petr Pysek

International Congress on Environmental Modelling and Software

The spatiotemporal dynamics of an alien species invasion across a real landscape are typically complex. While surveillance is an essential part of a management response, planning surveillance in space and time present a difficult challenge due to this complexity. We show here a method for determining the highest probability sites for occupancy across a landscape at an arbitrary point in the future, based on occupancy data from a single slice in time. We apply to the method to the invasion of Giant Hogweed, a serious weed in the Czech republic and throughout Europe.

The Data Processing Inequality And Environmental Model Prediction, Steven V. Weijs

International Congress on Environmental Modelling and Software

Prediction in environmental systems, such as hydrological streamflow prediction, is a challenging task. Although on a small scale, many of the physical processes are well described, accurate predictions of macroscopical (e.g. catchment scale) behavior with a bottom-up mechanistic approach often remains elusive. On the other hand, conceptual or purely statistical models fitted to data often perform surprisingly well for prediction. The data processing inequality, from the field of information theory, says that processing data with statistical procedures can only decrease, and not increase the information content of the data. This seems to contradict the intuition that our knowledge of physical …

Sand Sea Extents And Sediment Volumes On Titan From Dune Parameters, Karl D. Arnold

Theses and Dissertations

Linear dunes are one of the most abundant and important features on the surface of Titan. We present a model for estimating the volume of dune sediment using the area coverage of Titan's sand seas along with dune widths, spacings, and heights. This helps to reveal local sediment transport and deposition. We refine global dune area estimates from Cassini SAR (Synthetic Aperture RADAR) of 20 million km2 or 24 ± 3% of Titan's surface based on ~50% Cassini RADAR global coverage. Additionally, the global area of sand seas is estimated from a joint analysis of Cassini SAR and ISS (Imaging …