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Makris, K. (author), Langeveld, J.G. (author), Clemens, F.H.L.R. (author)Polyvinyl chloride (PVC) has become one of the dominant construction materials for sewer systems over the past decades, as a result of its reputed merits. However, since PVC sewer pipes have operated for decades in a hostile environment, concern over their longevity has been lately raised by sewer managers in the Netherlands. Towards that...journal article 2019
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Panasiuk, Oleksandr (author), Hedström, Annelie (author), Langeveld, J.G. (author), de Haan, Cornelis (author), Liefting, Erik (author), Schilperoort, Remy (author), Viklander, Maria (author)Infiltration and inflow (I/I) into sewers cause negative effects on the sewer system, wastewater treatment plant and environment. Identifying the causes and locating the inflows is necessary in order to address the I/I problem. This paper focuses on using distributed temperature sensing (DTS) for identifying, locating and characterising I/I...journal article 2019
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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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Beekers, D.I. (author), Lattwein, Kirby R. (author), Kouijzer, Joop J.P. (author), Langeveld, Simone A.G. (author), Vegter, M. (author), Beurskens, Robert (author), Mastik, F. (author), Verduyn Lunel, Rogier (author), van der Steen, A.F.W. (author), de Jong, N. (author)Controlling microbubble-mediated drug delivery requires the underlying biological and physical mechanisms to be unraveled. To image both microbubble oscillation upon ultrasound insonification and the resulting cellular response, we developed an optical imaging system that can achieve the necessary nanosecond temporal and nanometer spatial...journal article 2019
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Moreno Rodenas, A. (author), Langeveld, J.G. (author), Clemens, F.H.L.R. (author)Water quality environmental assessment often requires the joint simulation of several subsystems (e.g. wastewater treatment processes, urban drainage and receiving water bodies). The complexity of these integrated catchment models grows fast, leading to potentially over-parameterised and computationally expensive models. The receiving water body...journal article 2019
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Moreno Rodenas, A. (author), Bellos, V. (author), Langeveld, J.G. (author), Clemens, F.H.L.R. (author)This work presents a method to emulate the flow dynamics of physically based hydrodynamic simulators under variations of time-dependent rainfall and parametric scenarios. Although surrogate modelling is often employed to deal with the computational burden of this type of simulators, common techniques used for model emulation as polynomial...journal article 2018
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Nieuwenhuis, E.M. (author), Post, J.A.B. (author), Duinmeijer, S.P.A. (author), Langeveld, J.G. (author), Clemens, F.H.L.R. (author)The accumulation of FOG (Fat, Oil and Grease) deposits in sewer pumping stations results in an increase in maintenance costs, malfunctioning of pumps and, a potential increase of wastewater spills in receiving open water bodies. It is thought that a variety of parameters (e.g. geometry of the pump sump, pump operation, socioeconomic...journal article 2018
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van Bijnen, J.A.C. (author), Korving, J.L. (author), Langeveld, J.G. (author), Clemens, F.H.L.R. (author)Due to a variety of contaminants in floodwater, exposure to urban pluvial flooding may pose a health risk to humans. In-sewer defects may cause increased pluvial flooding, possibly increasing health risks. This paper addresses the impact of in-sewer defects on urban pluvial flooding and, subsequently, on infection probabilities for humans. As...journal article 2018
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Meijer, D.H. (author), van Bijnen, J.A.C. (author), Langeveld, J.G. (author), Korving, J.L. (author), Post, J.A.B. (author), Clemens, F.H.L.R. (author)Underground water infrastructure is essential for life in cities. The aging of these infrastructures requires maintenance strategies to maintain a minimum service level. Not all elements are equally important for the functioning of the infrastructure as a whole. Identifying the most critical elements in a network is crucial for formulating...journal article 2018
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Cecinati, Francesca (author), Moreno Rodenas, A. (author), Rico-Ramirez, Miguel A. (author), ten Veldhuis, Marie-claire (author), Langeveld, J.G. (author)In urban hydrological models, rainfall is the main input and one of the main sources of uncertainty. To reach sufficient spatial coverage and resolution, the integration of several rainfall data sources, including rain gauges and weather radars, is often necessary. The uncertainty associated with rain gauge measurements is dependent on...journal article 2018
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Moreno Rodenas, A. (author), Cecinati, Francesca (author), Langeveld, J.G. (author), Clemens, F.H.L.R. (author)Integrated Catchment Modelling aims to simulate jointly urban drainage systems, wastewater treatment plant and rivers. The effect of rainfall input uncertainties in the modelling of individual urban drainage systems has been discussed in several studies already. However, this influence changes when simultaneously simulating several urban...journal article 2017
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Kraaikamp, C. (author), Langeveld, Niels (author)In this paper we consider continued fraction (CF) expansions on intervals different from [0,1]. For every x in such interval we find a CF expansion with a finite number of possible digits. Using the natural extension, the density of the invariant measure is obtained in a number of examples. In case this method does not work, a Gauss–Kuzmin...journal article 2017
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- Hendriks, A.T.W.M. (author), Langeveld, J.G. (author) journal article 2017
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Langeveld, J.G. (author), van Daal-Rombouts, P.M.M. (author), Schilperoort, Remy (author), Nopens, Ingmar (author), Flameling, Tony (author), Weijers, Stefan (author)Wastewater treatment plants (WWTP) typically have a service life of several decades. During this service life, external factors, such as changes in the effluent standards or the loading of the WWTP may change, requiring WWTP performance to be optimized. WWTP modelling is widely accepted as a means to assess and optimize WWTP performance. One of...journal article 2017
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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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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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Post, J.A.B. (author), Langeveld, J.G. (author), Clemens, F.H.L.R. (author)The performance of lateral house connections has a direct impact on sewer serviceability. Despite the potential consequences of a blockage, these components are generally maintained with a reactive approach. As inspection data on the condition of lateral house connections are scarce, this study adopts a statistical procedure to support...journal article 2016
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van Daal-Rombouts, P.M.M. (author), Sun, Siao (author), Langeveld, J.G. (author), Bertrand-Krajewski, J.-L. (author), Clemens, F.H.L.R. (author)Optimisation or real time control (RTC) studies in wastewater systems increasingly require rapid simulations of sewer systems in extensive catchments. To reduce the simulation time calibrated simplified models are applied, with the performance generally based on the goodness of fit of the calibration. In this research the performance of three...journal article 2016
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van Riel, W. (author), Post, J.A.B. (author), Langeveld, J.G. (author), Herder, P.M. (author), Clemens, F.H.L.R. (author)Operational decision-making processes for networked infrastructure management often occur as a multi-actor planning problem, implying these are based on negotiations between different stakeholders in addition to available system quality information. As such, does more accurate data about actual structural condition lead to other or better...journal article 2016
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Stanic, N. (author), Langeveld, J.G. (author), Salet, Theo (author), Clemens, F.H.L.R. (author)Drill core samples are taken in practice for an analysis of the material characteristics of concrete pipes in order to improve the quality of the decision-making on rehabilitation actions. Earlier research has demonstrated that core sampling is associated with a significant uncertainty. In this paper, the results of core samples are compared...journal article 2016