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Arithmetic Units For The Elliptic Curve Cryptography With Concurrent Error Detection Capability, Arash Hariri Dec 2010

Arithmetic Units For The Elliptic Curve Cryptography With Concurrent Error Detection Capability, Arash Hariri

Electronic Thesis and Dissertation Repository

The elliptic curve cryptography is an important branch in public-key cryptography. In this thesis, we consider the elliptic curve cryptography over binary extension fields from two different points of view. First, we investigate the underlying arithmetic operations in the elliptic curve cryptography. The main arithmetic operation is the scalar multiplication. This operation is based on two elliptic curve operations, known as the point addition and point doubling. Implementing these two elliptic curve operations requires finite field arithmetic, specifically, finite field addition, multiplication, squaring, and inversion. We focus on two finite field operations, namely finite field multiplication and squaring. For the …


Mapping The Flip Angle In Magnetic Resonance Imaging Using The Accelerated 3d Look-Locker Sequence, Trevor P. Wade Dec 2010

Mapping The Flip Angle In Magnetic Resonance Imaging Using The Accelerated 3d Look-Locker Sequence, Trevor P. Wade

Electronic Thesis and Dissertation Repository

In the ongoing quest to extract more information from MRI images, there has arisen a need to rapidly map the flip angle. This has been primarily driven by the shift to stronger main field strengths, which bring with them improved SNR, but also new difficulties. In particular, the radio frequency field used to excite the magnetization can no longer be assumed uniform at field strengths of 3 Tesla and above. New rapid quantitative imaging techniques, such as DESPOT1 and DESPOT2, rely on accurate knowledge of the flip angle, and while this could safely be assumed to be the prescribed value …


Wake Dynamics And Passive Flow Control Of A Blunt Trailing Edge Profiled Body, Lakshmana Sampat Doddipatla Dec 2010

Wake Dynamics And Passive Flow Control Of A Blunt Trailing Edge Profiled Body, Lakshmana Sampat Doddipatla

Electronic Thesis and Dissertation Repository

Wake flows behind two-dimensional bodies are dominated mainly by two types of coherent structures, namely, the Karman Benard vortices and the streamwise vortices, also referred to as rolls and ribs respectively. The three-dimensional wake instabilities lead to distinct instability modes (mode-A, mode-B and mode-C or mode S) depending on the flow Reynolds number and geometric shape. The present investigation explores the mechanism by which the flow transitions take place to three-dimensionality in the near wake of a profiled leading edge and blunt trailing edge body. Experiments consisting of a combination of Planar Laser Induced Fluorescence visualizations and Particle Image Velocimetry …


A Step Towards Continuous Production Of Nay Zeolite In Amorphous Silica Particles Using A Dry Process, Syed Sameen Ali Zaidi Dec 2010

A Step Towards Continuous Production Of Nay Zeolite In Amorphous Silica Particles Using A Dry Process, Syed Sameen Ali Zaidi

Electronic Thesis and Dissertation Repository

This thesis is focused on the synthesis of nano-size (50-100nm) NaY zeolite crystals inside the micro/meso pores of preshaped amorphous silica particles of size 50 micrometer using a dry process, which reduced several operational steps and the zeolite synthesis time that are generally required for current in-practice processes. Three types of reactors namely; polypropylene bottles, a stainless steel tubular reactor, and a novel vibrated baffles fluidized bed (VBFB) reactor coupled with infrared radiation emitters were used to evaluate the effects of different operating parameters on the synthesis of NaY zeolite. The synthesis process took place without using any structure directing …


Nickel-Based Catalysts For Gasification Of Glucose In Supercritical Water, Muhammad Badrul Islam Chowdhury Dec 2010

Nickel-Based Catalysts For Gasification Of Glucose In Supercritical Water, Muhammad Badrul Islam Chowdhury

Electronic Thesis and Dissertation Repository

Gasification of waste biomass to form hydrogen, H2, is a promising new source of green energy; while providing the additional benefit of treating challenging and hazardous waste streams that pollute the environment. Gasification of biomass in supercritical water (SCW) offers an attractive alternative to avoid the energy intensive drying process. In this approach, biomass is hydrolyzed by water into smaller molecules in the presence of a suitable catalyst. This study was aimed at developing an alumina supported nickel based non-noble metal catalyst suitable for biomass gasification in SCW. A lack of detailed characterization on fresh and spent catalysts in SCW …


A New Signal Processing Approach To Study Action Potential Content In Sympathetic Neural Signals, Aryan Salmanpour Nov 2010

A New Signal Processing Approach To Study Action Potential Content In Sympathetic Neural Signals, Aryan Salmanpour

Electronic Thesis and Dissertation Repository

Sympathetic nerve activity plays an essential role in the normal regulation of blood pressure in humans and in the etiology and progression of many chronic diseases. Sympathetic nerve recordings associated with blood pressure regulation can be recorded directly using microneurography. A general characteristic of this signal is spontaneous burst activity of spikes (action potentials) separated by silent periods against a background of considerable gaussian noise. During measurement with electrodes, the raw muscle sympathetic nerve activity (MSNA) signal is amplified, band-pass filtered, rectified and integrated. This integration process removes important information regarding action potential content and their discharge properties.

The first …


Motion Coordination Of Aerial Vehicles, Abdelkader Abdessameud Nov 2010

Motion Coordination Of Aerial Vehicles, Abdelkader Abdessameud

Electronic Thesis and Dissertation Repository

The coordinated motion control of multiple vehicles has emerged as a field of major interest in the control community. This thesis addresses two topics related to the control of a group of aerial vehicles: the output feedback attitude synchronization of rigid bodies and the formation control of Unmanned Aerial Vehicles (UAVs) capable of Vertical Take-Off and Landing (VTOL). The information flow between members of the team is assumed fixed and undirected. The first part of this thesis is devoted to the attitude synchronization of a group of spacecraft. In this context, we propose control schemes for the synchronization of a …


Collision Detection And Merging Of Deformable B-Spline Surfaces In Virtual Reality Environment, Harish Pungotra Nov 2010

Collision Detection And Merging Of Deformable B-Spline Surfaces In Virtual Reality Environment, Harish Pungotra

Electronic Thesis and Dissertation Repository

This thesis presents a computational framework for representing, manipulating and merging rigid and deformable freeform objects in virtual reality (VR) environment. The core algorithms for collision detection, merging, and physics-based modeling used within this framework assume that all 3D deformable objects are B-spline surfaces. The interactive design tool can be represented as a B-spline surface, an implicit surface or a point, to allow the user a variety of rigid or deformable tools. The collision detection system utilizes the fact that the blending matrices used to discretize the B-spline surface are independent of the position of the control points and, therefore, …


Atomic Force Microscopy For Better Probing Surface Properties At Nanoscale: Calibration, Design And Application, Yu Liu Oct 2010

Atomic Force Microscopy For Better Probing Surface Properties At Nanoscale: Calibration, Design And Application, Yu Liu

Electronic Thesis and Dissertation Repository

To measure force by AFM with high resolution requires accurate calibration of optic – lever detection sensitivity and spring constant. On biological AFM force mode, the coupling effects of the liquid environment, spot size of laser beam and laser spot location on AFM cantilever backside, must be considered to correlate the static sensitivities from force curves in air and in liquid for calibration. An effective model has been developed first and experimentally elucidated to calibrate the static sensitivity in liquid. The proposed model eliminates inconvenience of static sensitivity calibration in liquid with possible contamination sources.

The static sensitivity based on …


Numerical Assessment Of Roof Panel Uplift Capacity Under Wind Load, Weixian He Oct 2010

Numerical Assessment Of Roof Panel Uplift Capacity Under Wind Load, Weixian He

Electronic Thesis and Dissertation Repository

ABSTRACT

The integrity of the roof system is essential for ensuring the safety of inhabitants and preventing excessive damage to light-frame wood structures. The uplift capacity of fastened roof panels has been investigated using experimental tests and numerical models, where monotonic uniform static pressures are often applied to the roof panel models. The verification is needed for the adequacy of using static uniformly distributed pressure representing the wind load. Moreover, the uncertainty of nail withdrawal behaviour has not been included in existing numerical models, and the effect due to construction errors has not been addressed rationally.

A nonlinear Finite Element …


Ontological View-Driven Semantic Integration In Open Environments, Yunjiao Xue Sep 2010

Ontological View-Driven Semantic Integration In Open Environments, Yunjiao Xue

Electronic Thesis and Dissertation Repository

In an open computing environment, such as the World Wide Web or an enterprise Intranet, various information systems are expected to work together to support information exchange, processing, and integration. However, information systems are usually built by different people, at different times, to fulfil different requirements and goals. Consequently, in the absence of an architectural framework for information integration geared toward semantic integration, there are widely varying viewpoints and assumptions regarding what is essentially the same subject. Therefore, communication among the components supporting various applications is not possible without at least some translation. This problem, however, is much more than …


Response Of A Two-Story Residential House Under Realistic Fluctuating Wind Loads, Murray J. Morrison Sep 2010

Response Of A Two-Story Residential House Under Realistic Fluctuating Wind Loads, Murray J. Morrison

Electronic Thesis and Dissertation Repository

Severe wind storms such as tropical cyclones, tornados, downbursts etc. can cause significant damage to infrastructure. Damage surveys following these events have shown that the roofs of residential, wood-frame construction are particularly vulnerable to failures. While damage surveys provide detail information of what components fail, they cannot provide the loads at which these failures occurred or how they initiated. Wind tunnel pressure models provide detailed information of the wind loads on buildings, however, they are not able to predict failures or how these loads are transferred through the structure. In order to better understand the response of wood framed houses …


Addressing Computational Complexity Of Electromagnetic Systems Using Parameterized Model Order Reduction, Majid Ahmadloo Aug 2010

Addressing Computational Complexity Of Electromagnetic Systems Using Parameterized Model Order Reduction, Majid Ahmadloo

Electronic Thesis and Dissertation Repository

As operating frequencies increase, full wave numerical techniques such as the finite element method (FEM) become necessary for the analysis of high-frequency and microwave circuit structures. However, the FEM formulation of microwave circuits often results in very large systems of equations which are computationally expensive to solve. The objective of this thesis is to develop new parameterized model order eduction (MOR) techniques to minimize the computational complexity of microwave circuits. MOR techniques provide a mechanism to generate reduced order models from the detailed description of the original FEM formulation. The following contributions are made in this thesis:

1. The first …


Controlled Delivery Of Serp-1 Protein From Poly(Vinyl Alcohol) Hydrogel, Karen L. Kennedy Aug 2010

Controlled Delivery Of Serp-1 Protein From Poly(Vinyl Alcohol) Hydrogel, Karen L. Kennedy

Electronic Thesis and Dissertation Repository

Poly(vinyl alcohol) (PVA) was selected and evaluated as a controlled drug delivery matrix for Serp-1, a potential new therapeutic with anti-inflammatory properties for control of restenosis. PVA hydrogels, containing a high water content, can be formed by physical crosslinking via a process involving freezing and thawing the material in multiple cycles. PVA, being a well known biomaterial, is suited for biomedical applications and the high water content and hydrophilicity provides a friendly environment for the delivery of large protein based drugs. Using bovine serum albumin (BSA) as a model protein, the controlled release properties of PVA were investigated. Release profiles …


Virtual And Augmented Reality Techniques For Minimally Invasive Cardiac Interventions: Concept, Design, Evaluation And Pre-Clinical Implementation, Cristian A. Linte Aug 2010

Virtual And Augmented Reality Techniques For Minimally Invasive Cardiac Interventions: Concept, Design, Evaluation And Pre-Clinical Implementation, Cristian A. Linte

Electronic Thesis and Dissertation Repository

While less invasive techniques have been employed for some procedures, most intracardiac interventions are still performed under cardiopulmonary bypass, on the drained, arrested heart. The progress toward off-pump intracardiac interventions has been hampered by the lack of adequate visualization inside the beating heart.

This thesis describes the development, assessment, and pre-clinical implementation of a mixed reality environment that integrates pre-operative imaging and modeling with surgical tracking technologies and real-time ultrasound imaging. The intra-operative echo images are augmented with pre-operative representations of the cardiac anatomy and virtual models of the delivery instruments tracked in real time using magnetic tracking technologies. As …


The Effect Of Particle Size On Hydrolysis And Modeling Of Anaerobic Digestion, Saad Aldin May 2010

The Effect Of Particle Size On Hydrolysis And Modeling Of Anaerobic Digestion, Saad Aldin

Electronic Thesis and Dissertation Repository

Batch experiments were performed to investigate the effect of particulate protein particle size on the hydrolysis of casein in anaerobic degradation. While particle size did not affect the ultimate protein degradation efficiency, the hydrolysis rate coefficient increased from 0.034 to 0.298 d-1 with the change in specific surface area from 0.01 to 0.192 m2/g. The maximum methane production rate was affected by the particle size change, although the ultimate amount of methane produced was approximately the same despite the change in specific surface area. A mathematical relationship between the hydrolysis rate coefficient and specific surface area was developed and a …


Catalytic Steam Gasification Of Biomass Surrogates: A Thermodynamic And Kinetic Approach, Enrique Salaices Mar 2010

Catalytic Steam Gasification Of Biomass Surrogates: A Thermodynamic And Kinetic Approach, Enrique Salaices

Electronic Thesis and Dissertation Repository

Gasification of biomass is an environmentally important technology that offers an alternative to the direct use of fossil fuel energy. Steam gasification is getting increased attention as a potential source of renewable energy since it produces a gaseous fuel suitable for industrial applications in highly efficiently power/heat energy production, transport fuel, and as a feedstock for chemical synthesis. Furthermore, catalytic steam gasification has other advantages hence (i) it produces a gas with higher heating value; (ii) it reduces the diluting effect of N2 from air; (iii) it eliminates the need of cleaning, upgrading and/or conditioning the product gas for certain …


Applications Of Ultrafine Powder Coatings, A.S. Mohammad Sayem Mozumder Jan 2010

Applications Of Ultrafine Powder Coatings, A.S. Mohammad Sayem Mozumder

Digitized Theses

Powder coatings have emerged as an alternative to the conventional liquid coatings when environmental regulations become stricter every year. The advantage of powder coatings mainly renders to their solvent-free formulations, because solvent(s) used in liquid coatings are to be evaporated to environment contributing to the total volatile organic compounds (VOCs) emissions. Although advantageous, until recently, powder coating was not able to provide surface finishes comparable to the liquid coatings. However, when ultrafine powders (particularly, in the size range of 15-25 µm) becomes flowable with the aid of nano-additive(s), ultrafine powder coatings (UPCs) came into business with its thinner and smoother …


Optimum Design Of Cable-Stayed Bridges, Mahmoud M. Hassan Jan 2010

Optimum Design Of Cable-Stayed Bridges, Mahmoud M. Hassan

Digitized Theses

Owing to their excellent structural characteristics, aesthetic appearance, low maintenance cost, and efficient use of structural materials, cable-stayed bridges have gained much popularity in recent decades. Stay cables of a cable stayed bridge are post-tensioned to counteract the effect of the bridge dead load. The solution for an optimum distribution of post-tensioning cable forces is considered one of the most important and difficult tasks in the design of cable-stayed bridges. A novel approach that utilizes the finite element method, B-spline curves, and real coded genetic algorithm to determine the global optimum post-tensioning cable forces is developed. The effect of geometric …