Due to age, original design that is deficient by modern standards, inadequate maintenance, environmental conditions, and increasing loads, large numbers of bridges in United States and elsewhere are classified as deficient and in need of rehabilitation or replacement. According to a national bridge inventory established by the Federal Highway Administration,...
Integral representations provide a useful framework of study and simulation of fractional Browian motion, which has been used in modeling of many natural situations. In this thesis we extend an integral representation of fractional Brownian motion that is supported on a bounded interval of ℝ to integral representation that is...
Long-term durability of surface-bonded carbon fiber-reinforced polymer (CFRP) U-wraps for shear strengthening of reinforced concrete (RC) bridge members remains uncertain due to the limited field experience with these materials. This paper provides experimental results from the testing of full-scale RC bridge girder specimens after exposure to prolonged freeze-thaw cycling. CFRP...
The dissertation uses state-of-the-art structural engineering theories, in parallel with the modern and still-developing control theory of electrical engineering to mitigate the vibratory responses of a double-stayed bridge subjected to strong earthquake ground motions.
First, a nonlinear finite element model of the double-stayed bridge subjected to non-uniform (multi-support) earthquake excitations...
The flow of incompressible, viscous fluids in R³ is governed by the non-linear Navier-Stokes equations. Two common linearizations of the Navier-Stokes equations, the Stokes equations and the Oseen equations, are studied in this thesis using probabilistic methods.
The incompressibility condition presents new challenges for the well known theory relating partial...
A perfectly matched layer (PML) is widely used to model many different types of wave propagation in different media. It has been found that a PML is often very effective and also easy to set, but still many questions remain.
We introduce a new formulation from regularizing the classical Un-Split...
3D vector tomography has been explored and results have been achieved in the last few decades. Among these was a reconstruction formula for the solenoidal part of a vector field from its Doppler transform with sources on a curve. The Doppler transform of a vector field is the line integral...
Oversampling analog-to-digital and digital-to-analog converters are gaining more
popularity in many signal processing applications. Delta-sigma modulators are used in practical applications of oversampling systems because of their apparent practical advantage over other oversampling converters in terms of insensitivity to the inevitable imperfection of the analog circuitry.
In Δ∑ modulators, analog...
The degenerate nature of the metric on null hypersurfaces creates many difficulties
when attempting to define a covariant derivative on null submanifolds. This dissertation
investigates these challenges and provides a technique for defining a connection on null
hypersurfaces in some cases. Recent approaches using decomposition to define a covariant
derivative...
The study of differentiation of integrals has led to the study of maximal functions. In the development of harmonic analysis, the most powerful result connected with Lebesgue's theorem was that of the Hardy-Littlewood Maximal Theorem. This maximal theorem implies Lebesgue's theorem, and the maximal function and its variants have played...