Searched for: subject:"Backscatter"
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Gaida, T.C. (author)
With the increasing human activities in the marine environment, such as fisheries, dredging, coastal protection or construction of marine infrastructure, seabed sediment and habitat mapping have become highly relevant for the development of sustainable marine management strategies. Compared to traditional mapping methods, primarily based on bed...
doctoral thesis 2020
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Gaida, T.C. (author), van Dijk, T.A.G.P. (author), Snellen, M. (author), Vermaas, Tommer (author), Mesdag, Chris (author), Simons, D.G. (author)
Natural and man-induced coastal erosion endanger life and environment in coastal areas worldwide. For sedimentary barrier coasts, beach and underwater nourishments are an efficient coastal protection strategy. To optimize nourishments and to understand their impact on the marine environment, monitoring strategies are required. In this study,...
journal article 2020
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Majid, A.Y. (author)
Battery-free energy-harvesting devices have the potential to operate for decades, since they draw power fromvirtually unlimited energy sources, such as sunlight. However, ambient energy sources are volatile, and tiny harvesters can extract only weak power from them. Thus, small energy-harvesting devices operate intermittently: first, they charge...
doctoral thesis 2020
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Wong, H.S. (author), Poole, A.B. (author), Wells, B. (author), Eden, M. (author), Barnes, R. (author), Ferrari, J. (author), Fox, R. (author), Yio, M.H.N. (author), Copuroglu, Oguzhan (author)
Water to cement (w/c) ratio is usually the most important parameter specified in concrete design and is sometimes the subject of dispute when a shortfall in concrete strength or durability is an issue. However, determination of w/c ratio in hardened concrete by testing is very difficult once the concrete has set. This paper presents the...
journal article 2020
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Gaida, T.C. (author), Mohammadloo, Tannaz H. (author), Snellen, M. (author), Simons, D.G. (author)
Multi-frequency multibeam backscatter (BS) has indicated, in particular for fine sediments, the potential for increasing the discrimination between different seabed environments. Fine sediments are expected to have a varying signal penetration within the frequency range of modern multibeam echosounders (MBESs). Therefore, it is unknown to...
journal article 2020
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Lin, J. (author), He, Qing (author), Guo, Leicheng (author), van Prooijen, Bram (author), Wang, Zhengbing (author)
Accurate measurement of suspended sediment concentration (SSC) in highly turbid environments has been a problem due to optical or acoustic signal saturation and attenuation. The saturation returns a limited measurement range, and the attenuation raises an ambiguity problem that a low optical or acoustic output could mean a low or a high SSC....
journal article 2020
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Koop, L. (author), Amiri Simkooei, A. (author), van der Reijden, Karin J. (author), O’Flynn, Sarah (author), Snellen, M. (author), Simons, D.G. (author)
High resolution maps of sandy seafloors are valuable to understand seafloor dynamics, plan engineering projects, and create detailed benthic habitat maps. This paper presents multibeam echosounder backscatter classification results of the Brown Bank area of the North Sea. We apply the Bayesian classification method in a megaripple and sand...
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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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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Brand, Evelien (author), De Sloover, Lars (author), De Wulf, Alain (author), Montreuil, Anne Lise (author), Vos, S.E. (author), Chen, Margaret (author)
Sediment transport is a key element in intertidal beach morphodynamics, but measurements of sediment transport are often unreliable. The aim of this study is to quantify and investigate cross-shore sediment transport and the resulting topographic changes for a tide-dominated, sandy beach. Two fortnight-long field experiments were carried out...
journal article 2019
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Snellen, M. (author), Gaida, T.C. (author), Koop, L. (author), Alevizos, Evangelos (author), Simons, D.G. (author)
Obtaining an overview of the spatial and temporal distribution of seabed sediments is of high interest for multiple research disciplines. Multibeam echosounders allow for the mapping of seabed sediments with high area coverage. In this paper, the repeatability of acoustic classification derived from multibeam echosounder backscatter is addressed...
journal article 2018
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Liu, Shengnan (author), Sotomi, Yohei (author), Eggermont, Jeroen (author), Nakazawa, Gaku (author), Torii, Sho (author), Ijichi, Takeshi (author), Onuma, Yoshinobu (author), Serruys, Patrick W. (author), Lelieveldt, B.P.F. (author), Dijkstra, J. (author)
An important application of intravascular optical coherence tomography (IVOCT) for atherosclerotic tissue analysis is using it to estimate attenuation and backscatter coefficients. This work aims at exploring the potential of the attenuation coefficient, a proposed backscatter term, and image intensities in distinguishing different...
journal article 2017
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Ghodrat, S. (author), Riemslag, A.C. (author), Kestens, L.A.I. (author)
Orientation contrast microscopy (i.e., electron backscattered diffraction, EBSD) was employed to monitor the plastic strain in loaded tensile samples of aluminium alloy Al6061 in T4 condition. The kernel average misorientation (KAM) is known to be an appropriate parameter in orientation contrast microscopy which has the potential to characterise...
journal article 2017
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Naghdy, Soroosh (author), Pirgazi, Hadi (author), Verleysen, Patricia (author), Petrov, R.H. (author), Kestens, L.A.I. (author)
International Union of Crystallography. The aim of this paper is to examine the morphological and crystallographic anisotropy that develops during high-pressure torsion (HPT) processing. Commercially pure aluminium was subjected to monotonic HPT deformation at room temperature. The microstructure and texture were studied by large-area electron...
journal article 2017
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Liu, Shengnan (author), Eggermont, Jeroen (author), Wolterbeek, Ron (author), Broersen, Alexander (author), Busk, Carol A.G.R. (author), Precht, Helle (author), Lelieveldt, B.P.F. (author), Dijkstra, Jouke (author)
Intravascular optical coherence tomography (IVOCT) is an imaging technique that is used to analyze the underlying cause of cardiovascular disease. Because a catheter is used during imaging, the intensities can be affected by the catheter position. This work aims to analyze the effect of the catheter position on IVOCT image intensities and to...
journal article 2016
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Martinez Bueno, P. (author), Martinez, M.J. (author), Rans, C.D. (author), Benedictus, R. (author)
The primary objective of this research study was to evaluate the capabilities for measuring strain of a composite UAV wing with an embedded optical fiber connected to a Rayleigh backscattering distributed sensing system. This research paper summarizes the manufacturing procedure used during the instrumentation of the composite UAV wing. In...
journal article 2016
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Pirgazi, H. (author), Glowinski, K. (author), Morawiec, A. (author), Kestens, L.A.I. (author)
Five macroscopic boundary parameters can be extracted from three-dimensional orientation maps. Serial sectioning, which includes consecutive steps of material removal, and electron backscatter diffraction (EBSD) measurement were employed to extract a stack of two-dimensional sections of a pure nickel sample. The EBSD patterns were collected from...
journal article 2015
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De Knijf, D. (author), Nguyen-Minh, T. (author), Petrov, R.H. (author), Kestens, L.A.I. (author), Jonas, J.J. (author)
The orientation dependence of the austenite-to-martensite transformation during uniaxial tensile testing was modelled using the phenomenological theory of martensite crystallography and the mechanical driving force. It was validated experimentally by means of electron backscatter diffraction measurements on a pre-defined zone of a quenched and...
journal article 2014
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Eilander, D.M. (author), Annor, F.O. (author), Iannini, L. (author), Van de Giesen, N.C. (author)
Multipurpose small reservoirs are important for livelihoods in rural semi-arid regions. To manage and plan these reservoirs and to assess their hydrological impact at a river basin scale, it is important to monitor their water storage dynamics. This paper introduces a Bayesian approach for monitoring small reservoirs with radar satellite images....
journal article 2014
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Snellen, M. (author), Eleftherakis, S. (author), Amiri-Simkooei, A. (author), Koomans, R.L. (author), Simons, D.G. (author)
This contribution presents sediment classification results derived from different sources of data collected at the Dordtse Kil river, the Netherlands. The first source is a multi-beam echo-sounder (MBES). The second source is measurements taken with a gamma-ray scintillation detector, i.e., the Multi-Element Detection System for Underwater...
journal article 2013
Searched for: subject:"Backscatter"
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