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602
Determination of the Manning coefficient from measured bed roughness
 in natural channels: U.S. Geological Survey Water Supply Paper 1898B,
, 1970
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Characteristics of Undular Hydraulic Jumps. Experimental Apparatus and Flow Patterns
 Journal of Hydraulic Engineering, ASCE
, 1995
"... Abstract: In open channels, the transition from supercritical to subcritical flows is called a hydraulic jump. For low upstream Froude numbers, freesurface undulations develop downstream of the jump and the hydraulic jump is called an undular jump. New experiments on undular hydraulic jumps were pe ..."
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Cited by 31 (15 self)
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Abstract: In open channels, the transition from supercritical to subcritical flows is called a hydraulic jump. For low upstream Froude numbers, freesurface undulations develop downstream of the jump and the hydraulic jump is called an undular jump. New experiments on undular hydraulic jumps were performed in a rectangular channel in which the upstream flows were fully developed turbulent shear flows. In this paper, the main flow patterns are described. Visual and photographic observations indicate five types of undular jumps. One of the main flow characteristics is the presence of lateral shock waves for Froude numbers larger than 1.2. The results show that the disappearance of undular jump occurs for Froude numbers ranging from 1.5 to 2.9 and that the wave length and amplitude of the freesurface undulations are functions of the upstream Froude number and the aspect ratio yc/W.
A sediment transport model for incision of gullies on steep topography
 Water Resources Research
, 2003
"... [1] We have conducted surveys of gullies that developed in a small, steep watershed in the Idaho Batholith after a severe wildfire followed by intense precipitation. We measured gully length and cross sections to estimate the volumes of sediment loss due to gully formation. These volume estimates ar ..."
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Cited by 27 (16 self)
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[1] We have conducted surveys of gullies that developed in a small, steep watershed in the Idaho Batholith after a severe wildfire followed by intense precipitation. We measured gully length and cross sections to estimate the volumes of sediment loss due to gully formation. These volume estimates are assumed to provide an estimate of sediment transport capacity at each survey cross section from the single gullyforming thunderstorm. Sediment transport models commonly relate transport capacity to overland flow shear stress, which is related to runoff rate, slope, and drainage area. We have estimated the runoff rate and duration associated with the gullyforming event and used the sediment volume measurements to calibrate a general physically based sediment transport equation in this steep, high shear stress environment. We find that a shear stress exponent of 3, corresponding to drainage area and slope exponents of M = 2.1 and N = 2.25, match our data. This shear stress exponent of 3 is approximately 2 times higher than those for bed load transport in alluvial rivers but is in the range of shear stress exponents derived from flume experiments on steep slopes and with total load equations. The concavity index of the gully profiles obtained theoretically from the area and slope
High Order Wellbalanced Finite Volume WENO Schemes for Shallow Water Equation with Moving Water
, 2007
"... A characteristic feature of hyperbolic systems of balance laws is the existence of nontrivial equilibrium solutions, where the effects of convective fluxes and source terms cancel each other. Recently a number of socalled wellbalanced schemes were developed which satisfy a discrete analogue of th ..."
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Cited by 27 (7 self)
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A characteristic feature of hyperbolic systems of balance laws is the existence of nontrivial equilibrium solutions, where the effects of convective fluxes and source terms cancel each other. Recently a number of socalled wellbalanced schemes were developed which satisfy a discrete analogue of this balance and are therefore able to maintain an equilibrium state. In most cases, applications treated equilibria at rest, where the flow velocity vanishes. Here we present a new very high order accurate, exactly wellbalanced finite volume scheme for moving flow equilibria. Numerical experiments show excellent resolution of unperturbed as well as slightly perturbed equilibria.
Robust continuoustime and discretetime flow control of a dam–river system. (II) Controller design
, 1999
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Exponential stability and transfer functions of processes governed by symmetric hyperbolic systems. ESAIM: Control, Optimisation and Calculus of Variations, 7, 421–442. Ababacar Diagne received a Graduate Degree in Applied Mathematics and Computer Science
, 2002
"... Abstract. In this paper we study the frequency and time domain behaviour of a heat exchanger network system. The system is governed by hyperbolic partial dierential equations. Both the control operator and the observation operator are unbounded but admissible. Using the theory of symmetric hyperboli ..."
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Cited by 26 (1 self)
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Abstract. In this paper we study the frequency and time domain behaviour of a heat exchanger network system. The system is governed by hyperbolic partial dierential equations. Both the control operator and the observation operator are unbounded but admissible. Using the theory of symmetric hyperbolic systems, we prove exponential stability of the underlying semigroup for the heat exchanger network. Applying the recent theory of wellposed innitedimensional linear systems, we prove that the system is regular and derive various properties of its transfer functions, which are potentially useful for controller design. Our results remain valid for a wide class of processes governed by symmetric hyperbolic systems. Mathematics Subject Classication. 93D09, 93D25, 80A20, 35L50.
A segmentation and classification approach of IKONOS2 imagery for land cover mapping to assist flood risk and flood damage assessment
 International Journal of Applied Earth Observation and Geoinformation
, 2003
"... Abstract Various regions in Europe have suffered from severe flooding over the last decennium. Earth observation techniques can contribute toward more accurate flood hazard modelling and they can be used to assess damage to residential properties, infrastructure and agricultural crops. For this stu ..."
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Cited by 26 (0 self)
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Abstract Various regions in Europe have suffered from severe flooding over the last decennium. Earth observation techniques can contribute toward more accurate flood hazard modelling and they can be used to assess damage to residential properties, infrastructure and agricultural crops. For this study, detailed land cover maps were created by using IKONOS2 high spatial resolution satellite imagery. The IKONOS2 image was first divided into segments and the land cover was classified by using spectral, spatial and contextual information with an overall classification accuracy of 74%. In spite of the high spatial resolution of the image, classes such as residential areas and roads are still fairly difficult to identify. The IKONOS2derived land cover map was used as input for the flood simulation model LISFLOODFP to produce a Manning roughness factor map of inundated areas. This map provides a more accurate spatial distribution of Manning's roughness factor than maps derived from land cover datasets such as the EU CORINE land cover dataset. CORINEderived roughness maps provide only averaged, lumped values of roughness factors for each mapping unit and are hence less accurate. Next, a method to produce a property damage map after flooding is presented. The detailed land cover map, water depth estimates resulting from the LISFLOODFP model, and known relations between water depth and property damage yielded a map of estimated property damage for the 1995 flood which affected the villages of Itteren and Borgharen in the southern part of The Netherlands. Such a map is useful information for decision makers and insurance companies.
Martian floods at Cerberus Fossae can be produced by groundwater discharge, Geophys
 Res. Lett
, 2004
"... Mars. In order to determine whether subsurface aquifers can discharge water sufficiently fast to explain these flood features, I develop a model that couples groundwater flow in a subcryosphere aquifer with flow through a fissure that penetrates from the surface to the aquifer. The model is constra ..."
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Cited by 22 (2 self)
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Mars. In order to determine whether subsurface aquifers can discharge water sufficiently fast to explain these flood features, I develop a model that couples groundwater flow in a subcryosphere aquifer with flow through a fissure that penetrates from the surface to the aquifer. The model is constrained by estimates of peak discharge, and the distance water flowed uphill from the fissure. Aquifer permeabilities similar to those of young basalt aquifers on the Earth, 109 m2, can produce inferred discharges of 106 m3/s [Burr et al., 2002a] but probably require multiple floods to create
Boundary control of hyperbolic conservation laws using a frequency domain approach
 In: Automatica 45.3 (2009
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Discontinuous galerkin methods for modeling hurricane storm surge
 Advances in Water Resources
, 2011
"... This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. ..."
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Cited by 18 (6 self)
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This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.