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Digital filtering methods, with applications to spacecraft attitude determination in the presence of modelling errors. Part II: Extension of theory, and applications

Traas, C.R. (author)

The present issue is the second and final part of a report describing the results of a study about digital filtering. The first part is available as the report NLR TR 760U8 U. The report considers a number of digital filtering methods and gives examples of their application. The methods include batch processing methods and recursive methods....

report 1979

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Ontwikkeling van een statistisch model en toepassing ervan op enkele waterkwaliteitsparameters uit het Hollands Diep en Haringvliet

Groot, S. (author)

report 1979

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An analysis of longshore currents and associated sediment transport in the surf zone

Ostendorf, D.W. (author), Madsen, O.S. (author)

Two momentum based longshore current models and a preliminary longshore sediment transport model are derived, calibrated and tested in the present investigation. The Linear Longshore Current Model predicts the relatively small longshore current induced by monochromatic, two dimensional, gravity waves of finite height and near normal incidence...

report 1979

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Modellering zoutindringing Rotterdamsche Waterweg ten behoeve van de PAWN-studie

Koenis, J.P. (author)

report 1979

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Steady turbulent flow in curved rectangular channels

De Vriend, H.J. (author)

After the study of fully developed and developing steady laminar flow in curved channels of shallow rectangular wet cross-section (see earlier reports in this series), steady turbulent flow in such channels is investigated as a next step towards a mathematical model of the flow in shallow river bends. A mathematical model is developed for this...

report 1979

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Streamline curvature and bed resistance in shallow water flow

De Vriend, H.J. (author)

The relationship between streamline curvature and bed resistance in shallow water flow with little side constraint, as derived in 1970 by H.J. Schoemaker, is reconsidered. Schoemaker concluded that the bed resistance causes the curvature of a free streamline to grow exponentially with the distance along this streamline, thus giving rise to a...

report 1979

document

Processing of Meteosat attitude measurement flight data and evaluation of the performance of an adaptive filtering technique

Traas, C.R. (author), Moek, G. (author)

The attitude measurement data of the ESA geosynchronous spacecraft METEOSAT have been analyzed using an adaptive recursive filtering technique developed at NLR. The mathematical models of spacecraft dynamics and sensors have been kept very simple. Modelling errors are such that, without adaptive feed-back, strong divergence of the filtering...

report 1978

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Accurate spacecraft attitude estimation with the ESA starmapper

van Woerkom, P.T.L.M. (author), Traas, C.R. (author)

The ESA starmapper is an optical-electronic instrument with an array of photo-sensitive slits, to "be strapped down to spinning spacecraft. Recorded times of passage of known stars over these slits, together with mathematical models for spacecraft dynamics and starmapper instrument, provide the basis for recursive estimation of the spacecraft...

report 1978

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Getijgootonderzoek: Projektenbeschrijving

Dronkers, J. (author)

report 1978

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Stormvloedkering Oosterschelde: Belasting op putten ten gevolge van grondwaterstroming

Vis, F.C. (author)

report 1978

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Visual scene perception process involved in the manual approach

Wewerinke, P.H. (author)

The outside scene is often an important soiirce of information for manual control tasks. In the context of aircraft control the most important example is the visual approach scene. This study deals with modelling the visual scene perception process on the basis of linear perspective geometry and the relative motion cues and investigates its...

report 1978

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Getijgootonderzoek: Eendimensionale numerieke berekening van getijbeweging en zoutverdeling in de getijgoot

Karelse, M. (author)

report 1978

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Stormvloedkering Oosterschelde - getijmodel Oosterschelde: Berekening van stroomsnelheden bij een aantal bouwfasen van de stormvloedkering

Hartsuiker, G. (author)

report 1978

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Stormvloedkering Oosterschelde: Krachten en trillingen bij de hefschuiven in de pijlerdam : vooronderzoek met een sektiemodel, schaal 1:40 in een kleine stroomgoot

Jong, R.J. de (author)

report 1978

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Behavior of Air Bubble Screens

Tekeli, S. (author), Maxwell, W.H.C. (author)

Bubble screens have long been used for a variety of purposes, ranging from control of stratification, density currents, oil spills, shoaling, icing and wave heights, to inducing artificial mixing for augmenting convective heat and mass transfer rates, aeration and water quality control. In spite of such potential, bubble screen applications have...

report 1978

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Stormvloedkering Oosterschelde - getijmodel Oosterschelde: Invloed plaats sluitgaten op stromingstoestand in en om de sluitgaten

Wijngaarden, N.J. van (author)

report 1978

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Stormvloedkering Oosterschelde - getijmodel Oosterschelde: Onderzoek stromingstoestand in de cunetten

Wijngaarden, N.J. van (author)

report 1978

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Stormvloedkering Oosterschelde - getijmodel Oosterschelde: Randvoorwaarden bij een plaatsingsfase van de pijlers op putten in de noordelijke sluitgaten

Wijngaarden, N.J. van (author)

report 1978

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Kuantan River, Malaysia: Prediction of salinity intrusion

Farleigh, D.R.P. (author)

A mathematical model was used to simulate the long-term movements of the high water slack longitudinal salinity profile in the estuary of the Sg Kuantan, Malaysia. The proven model was then used to predict the effects on salinity of increased abstractions from the estuary under various drought conditions. The predicted longitudinal profiles were...

report 1978

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Computations of a freshwater disposal into the Eastern Scheldt estuary

Perrels, P.A.J. (author)

report 1978