Now showing items 61-70 of 110
Deterministic Minimal Time Vessel Routing
(INFORMS, 1990-06)
We develop general methodologies for the minimal time routing problem of a vessel moving in stationary or time dependent environments, respectively. Local optimality considerations, combined with global boundary conditions, ...
Synchronous-Clock, One-Way-Travel-Time Acoustic Navigation for Underwater Vehicles
(Wiley, 2010-09-21)
This paper reports the development and deployment of a synchronous-clock acoustic navigation system suitable for the simultaneous navigation of multiple underwater vehicles. Our navigation system is composed of an acoustic ...
Toward extraplanetary under-ice exploration: Robotic steps in the Arctic
(Wiley Subscription Services, Inc., A Wiley Company, 2009-04)
This paper describes the design and use of two new autonomous underwater vehicles, Jaguar and Puma, which were deployed in the summer of 2007 at sites at 85°N latitude in the ice-covered Arctic Ocean to search for hydrothermal ...
Closed-form Approximations and Series Representations for Partially Saturated Ocean Acoustic Processes
(Acoustical Society of America, 1988-04)
An approximate, closed‐form expression for the value of the integral encountered in the calculation of the probability density function (PDF) of the envelope of a partially saturated ocean acoustic process is obtained. ...
An efficient finite element method for treating singularities in Laplace's equation
(Elsevier, 1991-10)
We present a new finite element method for solving partial differential equations with singularities caused by abrupt changes in boundary conditions or sudden changes in boundary shape. Terms from the local solution ...
Singular finite elements for the sudden-expansion and the die-swell problems
(John Wiley & Sons, Ltd, 1990-03)
The singular finite element method is used to solve the sudden-expansion and the die-swell problems in order to improve the accuracy of the solution in the vicinity of the singularity and to speed up the convergence. The ...
A singular finite element for Stokes flow: The stick–slip problem
(John Wiley & Sons, Ltd, 1989-11)
Abrupt changes in boundary conditions in viscous flow problems give rise to stress singularities. Ordinary finite element methods account effectively for the global solution but perform poorly near the singularity. In this ...
Velocity field measurements of cavitating flows
(Springer-Verlag, 1995-12)
A particle Image Velocimetry (PIV) system has been developed to study the microfluid mechanics of cavitating flows. Planar PIV was used to examine the non-cavitating flow in the thin boundary layer near a hydrofoil surface ...
Finite element structural redesign by large admissible perturbations
(Elsevier, 1992)
In structural redesign, two structural states are involved: the baseline (known) state S1 with unacceptable performance, and the objective (unknown) state S2 with given performance specifications. The difference between ...
Imaging Coral I: Imaging Coral Habitats with the SeaBED AUV
(Springer, 2004-01)
The SeaBED autonomous underwater vehicle (AUV) is a new imaging platform designed for
high resolution optical and acoustic sensing. This low cost vehicle has been specifically designed
for use in waters up to 2000 m to ...