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Simons, G.W.H. (author), Bastiaanssen, W.G.M. (author), Cheema, M.J.M. (author), Ahmad, B. (author), Immerzeel, W.W. (author)Increasing irrigation efficiencies remains the focus of numerous efforts to mitigate water scarcity. In reality, higher local efficiencies do often not reduce water scarcity, but instead cause a redistribution of water flows when the entire irrigation scheme or river basin is considered. Insufficient understanding of consumed fractions and non...journal article 2020
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Mohammadloo, Tannaz H. (author), Snellen, M. (author), Simons, D.G. (author)Realistic predictions of the contribution of the various sources affecting the quality of the bathymetric measurements prior to a survey are of importance to ensure sufficient accuracy of the soundings. To this end, models predicting these contributions have been developed. The objective of the present paper is to assess the performance of...journal article 2020
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Merino Martinez, R. (author), Neri, Eleonora (author), Snellen, M. (author), Kennedy, John (author), Simons, D.G. (author), Bennett, Gareth J. (author)The noise emissions of a full-scale nose landing gear (NLG), measured in a wind tunnel and obtained from computational simulations, are compared with those of three regional aircraft types recorded in flyover measurements. A comparison is made with the noise prediction models of Fink, Guo, and German Aerospace Center (DLR). A good agreement...journal article 2020
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Koop, L. (author), van der Reijden, Karin J. (author), Mestdagh, S.M.F. (author), Ysebaert, Tom (author), Govers, Laura L. (author), Olff, Han (author), Herman, P.M.J. (author), Snellen, M. (author), Simons, D.G. (author)Backscatter data from multibeam echosounders are commonly used to classify seafloor sediment composition. Previously, it was found that the survey azimuth affects backscatter when small organized seafloor structures, such as sand ripples, are present. These sand ripples are too small to be detected in the multibeam bathymetry. Here, we show that...journal article 2020
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Simons, G.W.H. (author), Droogers, Peter (author), Contreras, Sergio (author), Sieber, Jack (author), Bastiaanssen, W.G.M. (author)Water managers around the world face the increasingly challenging task to evaluate the impacts of technological measures and policy mechanisms from the local to the river basin scale. A toolset providing quantitative, actionable information on dependencies and trade-offs between upstream and downstream water users is currently lacking. Yet,...journal article 2020
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Brown, B. E. (author), Dunne, R. P. (author), Somerfield, P. J. (author), Edwards, A. J. (author), Simons, W.J.F. (author), Phongsuwan, N. (author), Putchim, L. (author), Anderson, L. (author), Naeije, M.C. (author)Effects of combined rising sea temperature and increasing sea level on coral reefs, both factors associated with global warming, have rarely been addressed. In this ~40 y study of shallow reefs in the eastern Indian Ocean, we show that a rising relative sea level, currently estimated at ~11 mm y−1, has not only promoted coral cover but also has...journal article 2019
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Mohammadloo, Tannaz H. (author), Snellen, M. (author), Simons, D.G. (author), Dierikx, Ben (author), Bicknese, Simon (author)Methods for gridding multibeam echo sounder (MBES) measurements to equidistant grids are proposed as alternatives to the shallowest measured depth, which is affected by outliers. The approaches considered use a combination of mean and standard deviation of soundings and the regression coefficient from the best fitted plane. These methods...journal article 2019
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Vieira, A.E. (author), Snellen, M. (author), Malgoezar, A.M.N. (author), Merino Martinez, R. (author), Simons, D.G. (author)Engine noise shielding is an important measure towards low-noise aircraft configurations. Such designs are supported by prediction tools that indicate high values for shielding of engine noise. Most prediction models approximate the complex nature of engine noise to simple noise sources such as monopoles or dipoles. This work compares...journal article 2019
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Amiri Simkooei, A. (author), Koop, L. (author), van der Reijden, Karin J. (author), Snellen, M. (author), Simons, D.G. (author)Seafloor characterization using multibeam echosounder (MBES) backscatter data is an active field of research. The observed backscatter curve (OBC) is used in an inversion algorithm with available physics-based models to determine the seafloor geoacoustic parameters. A complication is that the OBC cannot directly be coupled to the modeled...journal article 2019
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Merino Martinez, R. (author), Sijtsma, P. (author), Snellen, M. (author), Finez, A. (author), Herold, G. (author), Malgoezar, A.M.N. (author), Pereira, A. (author), Sarradj, E. (author), Simons, D.G. (author)Phased microphone arrays have become a well-established tool for performing aeroacoustic measurements in wind tunnels (both open-jet and closed-section), flying aircraft, and engine test beds. This paper provides a review of the most well-known and state-of-the-art acoustic imaging methods and recommendations on when to use them. Several...journal article 2019
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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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Amiri Simkooei, A. (author), Koop, L. (author), Snellen, M. (author), Simons, D.G. (author)In the last two decades, the use of multibeam echosounders has been growing for seafloor mapping and characterization. The former uses bathymetry data whereas the latter makes use of backscatter data. The use of backscatter data has been the subject of intensive research to gain insight into seafloor composition using either empirical or model...conference paper 2019
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- Riva, R.E.M. (author), Nijholt, N. (author), Simons, W.J.F. (author) poster 2019
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Malgoezar, A.M.N. (author), Vieira, A.E. (author), Snellen, M. (author), Simons, D.G. (author), Veldhuis, L.L.M. (author)Ducted propellers are an interesting design choice for unmanned aerial vehicle (UAV) concepts due to a potential increase of the propeller efficiency. In such designs, it is commonly assumed that introducing the duct also results in an overall noise reduction. The objective of this work is to experimentally analyze and quantify noise of a...review 2019
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Mohammadloo, Tannaz H. (author), Snellen, M. (author), Amiri Simkooei, A. (author), Simons, D.G. (author)Nowadays Multi-Beam Echo-Sounder (MBES) systems are used for obtaining information of the sea/river bed bathymetry and sediment composition. For the latter, use is usually made of the backscatter strength and depth derivatives, such as depth residuals. However, the depth derivatives are affected by the uncertainties inherent to the MBES varying...conference paper 2019
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Simons, L.P.A. (author), van den Heuvel, Wouter A C (author), Jonker, C.M. (author)WhatsApp was evaluated as a peer coach group support tool in a healthy lifestyle intervention with 15 young professionals. These individuals were time-constrained professionals, so two design challenges were to create enough attractiveness and quality in the peer group interactions. There were three main health domains: food, physical activity,...book chapter 2019
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Mohammadloo, Tannaz H. (author), Snellen, M. (author), Amiri Simkooei, A. (author), Simons, D.G. (author)Nowadays Multi-Beam Echo-Sounder (MBES) derived bathymetry is used for a large range of applications. However, these measurements are affected by the uncertainties inherent to the MBES. Since the development of the depth uncertainty prediction model, MBES systems have been improved noticeably. The present contribution addresses the importance of...conference paper 2019
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Luesutthiviboon, S. (author), Malgoezar, A.M.N. (author), Merino Martinez, R. (author), Snellen, M. (author), Sijtsma, P. (author), Simons, D.G. (author)The recently introduced high-resolution (HR)-CLEAN-SC algorithm for acoustic imaging provides ‘super-resolution’, i.e. the ability to discern sound sources located closer than the Rayleigh resolution limit. This is achieved by allowing the source markers to be relocated from the actual source locations within a certain constraint to avoid the...journal article 2019
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Merino Martinez, R. (author), Vieira, A.E. (author), Snellen, M. (author), Simons, D.G. (author)Aircraft noise is an increasingly important issue that causes annoyance and complaints for the communities living in the vicinity of airports. The conventional sound metrics (such as the A–weighted sound pressure level) typically used for assessing the impact of aircraft noise often fail to conveniently represent the actual annoyance...conference paper 2019
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Sambell, K.A.M. (author), Smets, P.S.M. (author), Simons, D.G. (author), Snellen, M. (author), Evers, L.G. (author)Continuous long-term sound sources are recorded at hydroacoustic station H03S, a threeelement hydrophone array south of Robinson Crusoe Island between 2014 April 23 and 2017 August 20. The origin of the signal between 3 and 20 Hz is investigated by using cross-correlation, array processing using plane wave beamforming and spectral analysis....journal article 2019