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The effect of uncertainties on the performance of real-time control of urban drainage systems

van der Werf, Job (author)

REAL-time control (RTC) is a technique used to dynamically control urban drainage systems to utilise the existing infrastructuremore optimally. It can be used to achieve a number of objectives aiming to improve the functioning of the urban drainage system, typically through the reduction of pollution. When heavy rainfall occurs, combined sewer...

doctoral thesis 2023

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The uncertainty associated with the use of copulas in multivariate analysis

Zhou, C. (author), van Nooijen, R.R.P. (author), Kolechkina, A.G. (author), Gargouri, E.F.G. (author), Slama, Fairouz (author), van de Giesen, N.C. (author)

The dependency structure between hydrological variables is of critical importance to hydrological modelling and forecasting. When a copula capturing that dependence is fitted to a sample, information on the uncertainty of the fit is needed for subsequent hydrological calculations and reasoning. A new method is proposed to report inferential...

journal article 2023

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A Rigorous Analysis of the Random Noise in Reflection Coefficients Synthesized via Mixed-Signal Active Tuners

Mubarak, F.A. (author), Muñoz Muñoz, F.A. (author), Spirito, M. (author)

In this contribution, we present a rigorous analysis based on uncertainty propagation techniques to estimate the random variation of the controlled reflection coefficient in mixed-signal load-pull test benches. A digital-to-analog converter is commonly used in these test benches to generate the baseband signal required to synthesize the high...

conference paper 2023

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A retrospective assessment of COVID-19 model performance in the USA

Colonna, Kyle J. (author), Nane, G.F. (author), Choma, Ernani F. (author), Cooke, R.M. (author), Evans, John S. (author)

Coronavirus disease 2019 (COVID-19) forecasts from over 100 models are readily available. However, little published information exists regarding the performance of their uncertainty estimates (i.e. probabilistic performance). To evaluate their probabilistic performance, we employ the classical model (CM), an established method typically used...

journal article 2022

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Early observability of EOR process effectiveness

Fatemi, S.A. (author)

This dissertation focuses on polymer flooding, as an example of an EOR process. Chemical floods such as polymer floods are EOR techniques intended to increase sweep and/or displacement efficiency. Even though the compatibility and the efficiency of the injected chemicals are thoroughly tested and validated in the laboratory, uncertainty still...

doctoral thesis 2021

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Sensitivity and uncertainty of the floris model applied on the lillgrund wind farm

van Beek, Maarten T. (author), Viré, A.C. (author), Andersen, Søren J. (author)

Wind farms experience significant efficiency losses due to the aerodynamic interaction between turbines. A possible control technique to minimize these losses is yaw-based wake steering. This paper investigates the potential for improved performance of the Lillgrund wind farm through a detailed calibration of a low-fidelity engineering model...

journal article 2021

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Benchmark PIV database for the validation of CFD simulations in a transitional cavity flow

Sciacchitano, A. (author), Arpino, F. (author), Cortellessa, G. (author)

We present an experimental benchmark database for the transitional cavity flow. The database is obtained by planar Particle Image Velocimetry measurements at the median plane of the cavity model, for Reynolds numbers between 6300 and 19,000 based on the cavity height. A detailed uncertainty analysis of the experimental results is performed...

journal article 2021

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Pupils returning to primary schools in England during 2020: Rapid estimations of punctual COVID-19 infection rates

Aspinall, W. P. (author), Sparks, R. S.J. (author), Woodhouse, M. J. (author), Cooke, R.M. (author), Scarrow, J. H. (author)

Drawing on risk methods from volcano crises, we developed a rapid COVID-19 infection model for the partial return of pupils to primary schools in England in June and July 2020, and a full return in September 2020. The model handles uncertainties in key parameters, using a stochastic re-sampling technique, allowing us to evaluate infection...

journal article 2021

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Do direct and inverse uncertainty assessment methods present the same results?

Ahmadi, Arman (author), Nasseri, M. (author)

Hydrological models are simplified imitations of natural and man-made water systems, and because of this simplification, always deal with inherent uncertainty. To develop more rigorous modeling procedures and to provide more reliable results, it is inevitable to consider and estimate this uncertainty. Although there are different approaches...

journal article 2020

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3D Ensemble Simulation of Seawater Temperature: An Application for Aquaculture Operations

Shettigar, Nithin Achutha (author), Bhattacharya, Biswa (author), Mészáros, L. (author), Spinosa, A. (author), El Serafy, G.Y.H. (author)

During the past decades, the aquaculture industry has developed rapidly, due to drop in wild fish catch. Water quality variables play major role in aquaculture operations, specifically seawater temperature has major impact on the metabolism of the fish species and therefore on the growth rate too. Since the fish farming business relies on the...

journal article 2020

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A Multi-Objective Approach for the Analysis of a Water-Food-Ecosystems Nexus at Basin Scale

Farrokhzadeh, S. (author), Abraham, E. (author), Ertsen, M.W. (author)

poster 2019

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Using Vine Copulas to Generate Representative System States for Machine Learning

Konstantelos, Ioannis (author), Sun, Mingyang (author), Tindemans, Simon H. (author), Issad, Samir (author), Panciatici, Patrick (author), Strbac, Goran (author)

The increasing uncertainty that surrounds electricity system operation renders security assessment a highly challenging task; the range of possible operating states expands, rendering traditional approaches based on heuristic practices and ad hoc analysis obsolete. In turn, machine learning can be used to construct surrogate models...

journal article 2019

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Uncertainty analysis in a large-scale water quality integrated catchment modelling study

Moreno Rodenas, A. (author), Tscheikner-Gratl, F. (author), Langeveld, J.G. (author), Clemens, F.H.L.R. (author)

Receiving water quality simulation in highly urbanised areas requires the integration of several processes occurring at different space-time scales. These integrated catchment models deliver results with a significant uncertainty level associated. Still, uncertainty analysis is seldom applied in practice and the relative contribution of the...

journal article 2019

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Geotechnical installation design of suction buckets in non-cohesive soils: A reliability-based approach

Remmers, J. (author), Reale, C. (author), Pisano, F. (author), Raymackers, Sylvie (author), Gavin, Kenneth (author)

This study presents a probabilistic analyses of suction bucket installation in cohesionless soils. The spatial variability of soil properties is quantified using a representative survey dataset from practice. Vertical random field modelling is used to model cone resistance variability and probability density functions are fitted using drained...

journal article 2019

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Discerning in-situ performance of an EOR agent in the midst of geological uncertainty I: Layer cake reservoir model

Fatemi, S.A. (author), Jansen, J.D. (author), Rossen, W.R. (author)

An enhanced-oil-recovery (EOR) pilot test has multiple goals, among them to demonstrate oil recovery, verify the properties of the EOR agent in-situ, and provide the information needed for scale-up to an economic process. Given the complexity of EOR processes and the inherent uncertainty in the reservoir description, it is a challenge to...

journal article 2017

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A Monte Carlo approach to the ship-centric Markov decision process for analyzing decisions over converting a containership to LNG power

Kana, A.A. (author), Harrison, B.M. (author)

A Monte Carlo approach to the ship-centric Markov decision process (SC-MDP) is presented for analyzing whether a container ship should convert to LNG power in the face of evolving Emission Control Area regulations. The SC-MDP model was originally developed as a means to analyze uncertain, sequential decision making problems. However, the...

journal article 2017

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Performance evaluation of a smart buffer control at a wastewater treatment plant

van Daal-Rombouts, P.M.M. (author), Benedetti, L (author), Jonge, J (author), Weijers, S (author), Langeveld, J.G. (author)

Real time control (RTC) is increasingly seen as a viable method to optimise the functioning of wastewater systems. Model exercises and case studies reported in literature claim a positive impact of RTC based on results without uncertainty analysis and flawed evaluation periods. This paper describes two integrated RTC strategies at the wastewater...

journal article 2017

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Performance evaluation of real time control in urban wastewater systems in practice: Review and perspective

van Daal-Rombouts, P.M.M. (author), Gruber, Günter (author), Langeveld, J.G. (author), Muschalla, Dirk (author), Clemens, F.H.L.R. (author)

Real time control (RTC) is generally viewed as a viable method for optimising the performance of urban wastewater systems. A literature review on the performance evaluation of RTC demonstrated a lack of consensus on how to do this. Two main deficiencies were identified: omitting uncertainty analysis and applying limited evaluation periods. A...

journal article 2017

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Uncertainty Analysis of Phytoplankton Dynamics in Coastal Waters

Niu, L. (author)

There is an increasing concern about the interactions between phytoplankton and coastal ecosystems, especially on the negative effects from coastal eutrophication and phytoplankton blooms. As the key indicator of the coastal ecosystem, phytoplankton plays an important role in the whole impact-effect chain. Primary production by phytoplankton...

doctoral thesis 2015

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The Copula Bayesian Network with mixed discrete and continuous nodes to forecast railway disruption lengths

Zilko, A.A. (author), Kurowicka, D. (author), Hanea, A.M. (author), Goverde, R.M.P. (author)

The highly uncertain nature of a railway disruption complicates the tasks carried by the Dutch Operational Control Centre Rail (OCCR) in the Netherlands. A good prediction of disruption length is believed to help the decision making in dealing with the disruption. Zilko, et al. [Non-Parametric Bayesian Network to Forecast Railway Disruption...

conference paper 2015