The usage of reclaimed water can efficiently mitigate water crises, but it may cause groundwater pollution. To clearly understand the potential influences of long-term reclaimed water usage, a total of 91 samples of shallow and deep groundwater were collected from a typical reclaimed water use area during the dry and rainy seasons. The results suggest both shallow and deep groundwater are mainl...

Underwater acoustic signal processing aims to reconstruct the shallow water acoustic channel from both direct arrival and delayed multipath reflections. This enables accurate acoustic communications in shallow water, such as between underwater autonomous vehicles (UAVs), which are essential for coastal surveillance and other applications. In this work, we take a previously implemented algorithm...

The ability to predict sound propagation in shallow water is limited by the knowledge of the geoacoustic properties of the ocean bottom. The long term goals of this research are: (1) to develop full field inversion methods for estimating parameters of geoacoustic models of the ocean bottom and the associated uncertainties in the model parameter values; and (2) to evaluate the performance of the...

Shallow water acoustics and the performance of sonar systems in littoral environments are critical areas of interest to the US Navy. In response to this, the Office of Naval Research sponsored a series of acoustics experiments in the East and South China Seas, hereafter referred to as ASIAEx. One of the components of these experiments was a study of shallow water reverberation. The long-term go...

A well balanced numerical scheme based on stationary waves for shallow water flows with arbitrary topography has been introduced by Thanh et al. [18]. The scheme was constructed so that it maintains equilibrium states and tests indicate that it is stable and fast. Applying the well-balanced scheme for the one-dimensional shallow water equations, we study the early shock waves propagation toward...

Data from a 10-month monitoring study during 2007 in the Everglades ecosystem provide insight into the variation of delta(18)O, deltaD, and ion chemistry in surface water and shallow groundwater. Surface waters are sensitive to dilution from rainfall and input from external sources. Shallow groundwater, on the other hand, remains geochemically stable during the year. Surface water input from ca...

The initial data and bottom topography, used as inputs in shallow water models, are prone to uncertainty due to measurement errors. We model this uncertainty statistically in terms of random shallow water equations. We extend the Multi-Level Monte Carlo (MLMC) algorithm to numerically approximate the random shallow water equations efficiently. The MLMC algorithm is suitably modified to deal wit...

We study the modulational instability of a shallow water model, with and without surface tension, which generalizes the Whitham equation to include bi-directional propagation. Without surface tension, the small amplitude periodic traveling waves are modulationally unstable if their wave number is greater than a critical wave number predicting a Benjamin-Feir type instability and the result qual...

In this paper we investigate the performance of the weighted essential non-oscillatory (WENO) methods based on different numerical fluxes, with the objective of obtaining better performance for the shallow water equations by choosing suitable numerical fluxes. We consider six numerical fluxes, i.e., Lax-Friedrichs, local Lax-Friedrichs, Engquist-Osher, Harten-Lax-van Leer, HLLC and the first-or...

A shallow water spectral wave prediction model based on a numerical solution of the radiative transfer equation is presented. The model is second generation and uses a simple yet effective representation for the nonlinear source term. In addition, the model pays particular attention to the shallow water processes of refraction, shoaling, bottom friction, and wave breaking. The flexibility of th...