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Kumar, Kavisha (author), Labetski, A. (author), Arroyo Ohori, G.A.K. (author), Ledoux, H. (author), Stoter, J.E. (author)LandInfra is a relatively new open standard for modelling and representing land and infrastructure features. As it overlaps with other open standards in BIM (IFC) and 3D GIS (CityGML), it has been recognised as a potential candidate to bridge the gap between the two domains. However, the knowledge of this standard in both communities is low, and...journal article 2019
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Hajizad, O. (author), Kumar, A. (author), Li, Z. (author), Petrov, R.H. (author), Sietsma, J. (author), Dollevoet, R.P.B.J. (author)Wheel–rail contact creates high stresses in both rails and wheels, which can lead to different damage, such as plastic deformation, wear and rolling contact fatigue (RCF). It is important to use high-quality steels that are resistant to these damages. Mechanical properties and failure of steels are determined by various microstructural...journal article 2019
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Liu, Z. (author), Ghatkesar, M.K. (author), Sudhölter, Ernst J. R. (author), Singh, Binder (author), Kumar, N. (author)Surfactants have the ability to mobilize residual oil trapped in pore spaces of matrix rocks by lowering the oil-water interfacial tension, resulting in a higher oil recovery. However, the loss of surfactants by adsorption onto the rock surface has become a major concern that reduces the efficiency of the surfactant flooding process. In this...journal article 2019
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Haaring, Robert (author), Kumar, N. (author), Bosma, D. (author), Poltorak, L. (author), Sudhölter, Ernst J. R. (author)The ability to study the adsorption behavior of surfactant species is of interest in the field of enhanced oil recovery (EOR), especially pertaining to alkaline surfactant flooding. In this work, a calcite model mineral surface was obtained by electrochemically assisted deposition. This was achieved via the nitrate and/or oxygen...journal article 2019
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Kumar, Kavisha (author), Labetski, A. (author), Ledoux, H. (author), Stoter, J.E. (author)The Level of Detail (LOD) concept in CityGML 2.0 is meant to differentiate the multiple representations of semantic 3D city models. Despite the popularity and general acceptance of the concept by the practitioners and stakeholders in 3D city modelling, there are still some limitations. While the CityGML LOD concept is well defined for buildings,...journal article 2019
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Kumar, Kavisha (author), Labetski, A. (author), Agugiaro, G. (author), Stoter, J.E. (author)GIS has become an important part of many disciplines and supports a vast range of applications. It is used everywhere, from agriculture to public health care. Furthermore, with the advances in technologies, the availability of GIS data and software support has grown exponentially. In this paper, we present the results of our international survey...journal article 2019
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Kumar, P. (author), Fanzio, P. (author), Sasso, L. (author), Langelaar, Matthijs (author)The concept and synthesis approach for planar Compliant Fluidic Control Structures (CFCSs), monolithic flexible continua with embedded functional pores, is presented in this manuscript. Such structures are envisioned to find application in biomedicine as tunable microfluidic devices for drug/nutrient delivery. The functional pores enlarge and...journal article 2019
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Kumar, A. (author), Agarwal, G. (author), Petrov, R.H. (author), Goto, S. (author), Sietsma, J. (author), Herbig, M. (author)The formation of White (WEL) and Brown Etching Layers (BEL) on rail raceways during service causes the initiation of microcracks which finally leads to failure. Detailed characterization of the WEL and the BEL in a pearlitic rail steel is carried out from micrometer to atomic scale to understand their microstructural evolution. A...journal article 2019
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Goulas, C. (author), Kumar, A. (author), Mecozzi, M.G. (author), Castro-Cerda, Felipe Manuel (author), Herbig, Michael (author), Petrov, R.H. (author), Sietsma, J. (author)Atomic-scale investigation was performed on 51CrV4 steel, isothermally held at different temperatures within the bainitic temperature range. Transmission electron microscopy (TEM) analysis revealed three different morphologies: lower, upper, and inverse bainite. Atom Probe Tomography (APT) analysis of lower bainite revealed cementite...journal article 2019
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Saxena, A.K. (author), Kumar, A. (author), Herbig, M. (author), Brinckmann, S. (author), Dehm, G. (author), Kirchlechner, C. (author)The fracture behavior of a white etching layer formed on the rail surface in pearlitic steels during the rail-wheel contact is investigated using indentation-based microcantilever fracture tests. The sample thickness is in the order of 5 μm. The local fracture toughness of the white etching layer, its neighboring brown etching layer, martensite...journal article 2019
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Kumar, Kavisha (author), Labetski, A. (author), Arroyo Ohori, G.A.K. (author), Ledoux, H. (author), Stoter, J.E. (author)The relatively new Open Geospatial Consortium (OGC) standard LandInfra documents in its data model land and civil engineering infrastructure features. It has a Geography Markup Language (GML) implementation, OGC InfraGML, which has essentially no software support and is rarely used in practice. In order to share the benefits of LandInfra (and...journal article 2019
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Messaadi, M. (author), Oomen, Matthijs (author), Kumar, A. (author)Bainitic steels are gaining popularity for application in the railway switches and crossing, thanks to their better rolling contact fatigue (RCF) and wear resistance. The rail degradation caused by RCF and wear could be also reduced by the use of friction modifiers (FM) through their ability to reduce the lateral load during wheel passage....journal article 2019
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Agarwal, G. (author), Kumar, A. (author), Richardson, I.M. (author), Hermans, M.J.M. (author)Solidification cracking susceptibility during laser welding was studied experimentally and numerically in advanced high strength steel sheets, namely transformation-induced plasticity (TRIP) and dual phase (DP) steel. Using the same heat input, laser bead-on-plate welding was carried out on single sided clamped specimens at various starting...journal article 2019
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Valdes-Tabernero, M. A. (author), Celada-Casero, Carola (author), Sabirov, I. (author), Kumar, A. (author), Petrov, R.H. (author)This work focuses on the effect of soaking time on the microstructure during ultrafast heat treatment of a 50% cold rolled low carbon steel with initial ferritic-pearlitic microstructure. Dilatometry analysis was used to estimate the effect of heating rate on the phase transformation temperatures and to select an appropriate inter-critical...journal article 2019
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Li, Bailing (author), Rodell, Matthew (author), Kumar, Sujay (author), Beaudoing, Hiroko Kato (author), Getirana, Augusto (author), Zaitchik, Benjamin F. (author), de Goncalves, Luis Gustavo (author), Cossetin, Camila (author), Steele-Dunne, S.C. (author)The scarcity of groundwater storage change data at the global scale hinders our ability to monitor groundwater resources effectively. In this study, we assimilate a state-of-the-art terrestrial water storage product derived from Gravity Recovery and Climate Experiment (GRACE) satellite observations into NASA's Catchment land surface model ...journal article 2019
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Kumar, A. (author), Saxena, A. K. (author), Kirchlechner, C. (author), Herbig, M. (author), Brinkmann, S. (author), Petrov, R.H. (author), Sietsma, J. (author)Failure in engineering materials like steels is strongly affected by in-service deleterious alterations in their microstructure. White Etching Layers (WELs) are an example of such in-service alterations in the pearlitic microstructure at the rail surface. Cracks initiate in the rails due to delamination and fracture of these layers and...journal article 2019
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Labetski, A. (author), Kumar, Kavisha (author), Ledoux, H. (author), Stoter, J.E. (author)While there exist international standards for geospatial metadata (ISO 19115), these are rarely used in practice for 3D datasets, and one of the OGC standards for 3D city models, CityGML, does not offer a mechanism to store metadata in a structured way. Having metadata in CityGML files, which are in practice often very large and complex, would...journal article 2018
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Kumar, P. (author), Luo, P. (author), Gaspar, Francisco J. (author), Oosterlee, C.W. (author)A multilevel Monte Carlo (MLMC) method for Uncertainty Quantification (UQ) of advection-dominated contaminant transport in a coupled Darcy–Stokes flow system is described. In particular, we focus on high-dimensional epistemic uncertainty due to an unknown permeability field in the Darcy domain that is modelled as a lognormal random field....journal article 2018
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Sharifi Dehsari, Hamed (author), Kumar, Manasvi (author), Ghittorelli, Matteo (author), Glasser, Gunnar (author), Lenz, Thomas (author), de Leeuw, D.M. (author), Torricelli, Fabrizio (author), Asadi, Kamal (author)Solution-processed memory diodes based on phase separated blends of ferroelectric and semiconducting polymers in the low resistance on-state operate similar to a vertical field-effect transistor at the pinch-off. Numerical simulations have shown that the performance of the diode is dominated by the conduction of charge carriers at the...journal article 2018
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Kelly, Elizabeth A. (author), Feng, Zhixuan (author), Gidley, Maribeth L. (author), Sinigalliano, Christopher D. (author), Kumar, Naresh (author), Donahue, Allison G. (author), Reniers, A.J.H.M. (author), Solo-Gabriele, Helena M. (author)When beach water monitoring programs identify poor water quality, the causes are frequently unknown. We hypothesize that management policies play an important role in the frequency of fecal indicator bacteria (FIB) exceedances (enterococci and fecal coliform) at recreational beaches. To test this hypothesis we implemented an innovative...journal article 2018