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Full-Text Articles in Engineering

Development Of A Novel Tio2-Polymeric Photocatalyst For Water Purification Both Under Uv And Solar Illuminations, Debjani Mukherjee Jun 2011

Development Of A Novel Tio2-Polymeric Photocatalyst For Water Purification Both Under Uv And Solar Illuminations, Debjani Mukherjee

Electronic Thesis and Dissertation Repository

Comprising about 70% of the Earth’s surface, water is undoubtedly the most precious natural resource. According to the W.H.O, around 3.5 million people are dying every year from different water related diseases. Different kinds of dyes and pharmaceutical products have been detected in drinking water, all over the world. These organic compounds being non removable by traditional water purification processes, made advanced oxidation processes come into existence. Among all kind of advanced oxidation processes, photocatalytic oxidation is the most promising one. The photocatalytic process is based on aqueous phase hydroxyl radical chemistry and couples low energy ...


Measurement Of Dynamic Temperatures And Pressures In Nuclear Power Plants, Hashem M. Hashemian Jun 2011

Measurement Of Dynamic Temperatures And Pressures In Nuclear Power Plants, Hashem M. Hashemian

Electronic Thesis and Dissertation Repository

The dynamic response of the process sensors that supply real-time data to the safety systems in nuclear power plants (NPP) play a vital role in preventing plant accidents. If a critical process temperature, pressure, level, or flow experiences a step change, for example, the sensors that measure the process variable must act quickly to actuate the safety systems that will mitigate the consequence of an undesirable process excursion. The research conducted for this dissertation has been performed to ensure the prompt response of critical sensors by advancing, refining, validating, and implementing new methods for measuring the response time of temperature ...


Functional Coatings: Superhydrophopbic And Conductive Coatings, Seyed Amirhossein Seyedmehdi Jun 2011

Functional Coatings: Superhydrophopbic And Conductive Coatings, Seyed Amirhossein Seyedmehdi

Electronic Thesis and Dissertation Repository

The natural world has many superhydrophobic and self-cleaning surfaces such as butterfly wings and lotus plant leaves, both well known examples of self-cleaning surfaces. Water droplets on these surfaces can pick up dirt particles and remove contamination. The significant self-cleaning ability of these surfaces has inspired many researchers to attempt to fabricate these superhydrophobic coatings, mimicking their self-cleaning properties, using different methods. Most of the superhydrophobic coatings described in current literature need to be cured in ovens and thus difficult to be applied and/or be maintained in the work place. Therefore, there is a need to develop room temperature ...


Supercritical Water Gasification Of Biomass & Biomass Model Compounds, Emhemmed A.E.A Youssef Jun 2011

Supercritical Water Gasification Of Biomass & Biomass Model Compounds, Emhemmed A.E.A Youssef

Electronic Thesis and Dissertation Repository

Supercritical water gasification (SCWG) is an innovative, modern, and effective destruction process for the treatment of organic compounds. Hydrogen production using SCWG of biomass or waste feedstocks is a promising approach towards cleaner fuel production while simultaneously providing novel solution for hard-to-treat organic wastes. The main premise of this work was to experimentally examine real waste biomass sources i.e. hog manure and waste biomass model compounds using SCW gasification while examining various commercial catalysts. The improvement of the SCWG process requires an understanding of the waste/biomass reaction chemistry, and thus the knowledge of the reaction mechanisms is critically ...


The Effect Of The Environment On The Corrosion Products And Corrosion Rates On Gas Transmission Pipelines, Brent Sherar Jun 2011

The Effect Of The Environment On The Corrosion Products And Corrosion Rates On Gas Transmission Pipelines, Brent Sherar

Electronic Thesis and Dissertation Repository

This thesis reports a series of investigations examining external corrosion processes along gas transmission pipelines. TransCanada PipeLines Ltd. (TCPL) has developed six proposed corrosion scenarios to describe external pipeline corrosion, based primarily on corrosion products and corrosion rates (CRs) observed at field sites. The six proposed corrosion scenarios can be divided into two groups: abiotic and biotic. The three abiotic corrosion scenarios are (1) anaerobic corrosion, (2) aerobic corrosion, and (3) anaerobic corrosion turning aerobic; while (4) anaerobic corrosion with microbial effects, (5) aerobic corrosion turning anaerobic with microbial effects, and (6) anaerobic corrosion with microbial effects turning aerobic comprise ...


Modeling Lung Tissue Motions And Deformations: Applications In Tumor Ablative Procedures, Ali Sadeghi Naini May 2011

Modeling Lung Tissue Motions And Deformations: Applications In Tumor Ablative Procedures, Ali Sadeghi Naini

Electronic Thesis and Dissertation Repository

Various types of motion and deformation that the lung undergoes during minimally invasive tumor ablative procedures have been investigated and modeled in this dissertation. The lung frequently undergoes continuous large respiratory deformation, which can greatly affect the pre-planned outcome of the operation, hence deformation compensation becomes necessary. The first type of major deformation involved in a target lung throughout a tumor ablative procedure is the one encountered in procedures where the lung is totally deflated before starting the operation. A consequence of this deflation is that pre-operative images (acquired while the lung was partially inflated) become inaccurate for targeting the ...


Experimental And Numerical Development Of Anchor-Jointed Precast Structural Wall System And Optimum Design Of Prestressed Slabs, Mohamed El Semelawy May 2011

Experimental And Numerical Development Of Anchor-Jointed Precast Structural Wall System And Optimum Design Of Prestressed Slabs, Mohamed El Semelawy

Electronic Thesis and Dissertation Repository

Precast concrete shear walls are used to resist lateral loads in low- to medium-rise buildings. An innovative joining technique is proposed to accelerate construction process and to reduce concrete damage possibility and capital loss during an earthquake event. Panels are jointed using steel anchor bolts, therefore, the system is designated "anchor-jointed precast structural wall system". In this system, anchors are utilized as a structural fuse. Damaged anchors are easily replaced after an earthquake, thus minimizing repair costs and serviceability disruptions. In the first part of this thesis, conceptual development of the system is carried out. A research program of combined ...


Uncertainty Estimation Of Extreme Precipitations Under Climate Change: A Non-Parametric Approach, Tarana A. Solaiman May 2011

Uncertainty Estimation Of Extreme Precipitations Under Climate Change: A Non-Parametric Approach, Tarana A. Solaiman

Electronic Thesis and Dissertation Repository

Assessment of climate change impacts on hydrology at watershed scale incorporates (a) downscaling of global scale climatic variables into local scale hydrologic variables and (b) assessment of future hydrologic extremes. Atmosphere-Ocean Global Climate Models (AOGCM) are designed to simulate time series of future climate responses accounting for human induced green house gas emissions. The present study addresses the following limitations of climate change impact research: (i) limited availability of observed historical information; (ii) limited research on the detection of changes in hydrologic extremes; and (iii) coarse spatio-temporal resolution of AOGCMs for use at regional or local scale. Downscaled output from ...


Early-Age Shrinkage Of Ultra High-Performance Concrete: Mitigation And Compensating Mechanisms, Ahmed Mohammed Soliman Apr 2011

Early-Age Shrinkage Of Ultra High-Performance Concrete: Mitigation And Compensating Mechanisms, Ahmed Mohammed Soliman

Electronic Thesis and Dissertation Repository

The very high mechanical strength and enhanced durability of ultra high-performance concrete (UHPC) make it a strong contender for several concrete applications. However, UHPC has a very low water-to-cement ratio, which increases its tendency to undergo early-age shrinkage cracking with a risk of decreasing its long-term durability. To reduce the magnitude of early-age shrinkage and cracking potential, several mitigation strategies have been proposed including the use of shrinkage reducing admixtures, internal curing methods (e.g. superabsorbent polymers), expansive cements and extended moist curing durations. To appropriately utilize these strategies, it is important to have a complete understanding of the driving ...


Particle Attrition With Supersonic Nozzles In A High Temperature Fluidized Bed, Feng Li Apr 2011

Particle Attrition With Supersonic Nozzles In A High Temperature Fluidized Bed, Feng Li

Electronic Thesis and Dissertation Repository

Fluidized beds are widely used for a variety of processes such as food, pharmaceutical, petrochemical and energy production. As a typical application of fluidized beds, the fluid coking process uses thermal cracking reactions to upgrade heavy oils and bitumen from oil sands. In order to maintain a well fluidized bed and a satisfactory operation, a series of supersonic nozzles are used to inject high pressure steam in the bed to maintain the coke particle within an optimal range. Currently, the attrition nozzles consume a large florwrate of high pressure and superheated steam, which accounts for about 40 % of the total ...


Investigation On Rheology Of Oil Well Cement Slurries, Anjuman Shahriar Apr 2011

Investigation On Rheology Of Oil Well Cement Slurries, Anjuman Shahriar

Electronic Thesis and Dissertation Repository

The rheology of OWC slurries is generally more complicated than that of conventional cement paste. In order to contend with bottom hole conditions (wide range of pressure and temperature), a number of additives are usually used in the OWC slurries and the slurry shows different characteristics depending on the combination of admixture used. The objective of this research is to develop a fundamental understanding on the important mechanisms that affects the rheology of cement slurry incorporating various chemical and mineral admixtures. The thesis aimed at developing cement slurries by partial replacement of oil well cement using different mineral admixtures, offering ...


Audible Acoustic Emissions For Monitoring High-Shear Granulation, Erin M. Hansuld Apr 2011

Audible Acoustic Emissions For Monitoring High-Shear Granulation, Erin M. Hansuld

Electronic Thesis and Dissertation Repository

High-shear wet granulation is a size enlargement process commonly used by the pharmaceutical industry to improve powder properties for downstream processes, such as tabletting. Granule growth however, is difficult to predict because the final product is sensitive to raw material properties and processing conditions. Development of process analytical technologies (PATs) is recommended by regulators to improve process understanding and monitor quality online.

This work investigates the robustness of AAEs as PAT for high-shear granulation. Condenser microphones suspended in the air exhaust were used to collect AAEs from granulation. Applying power spectral density (PSD) analysis, trends related to wetting and end-point ...


Fabrication, Modification And Application Of Visible Light Responsive Tio2 Nanotubes, Tayirjan Taylor Isimjan Apr 2011

Fabrication, Modification And Application Of Visible Light Responsive Tio2 Nanotubes, Tayirjan Taylor Isimjan

Electronic Thesis and Dissertation Repository

The highly ordered TiO2 nanotube arrays have demonstrated remarkable properties that include solar cells, hydrogen sensors, drug eluting surfaces, hydrogen generation, and water purification along with numerous other applications. Built upon a suitable fabrication approach that enable significant differences in reproducibility as well as the large scale production with low cost plus investigation of the effective way to increase its visible light response so that create environmental friendly alternative energy sources were the motivations of this work, Since the field has grown so rapidly as to make it difficult to summarize the scope of all related work, some key ...


Biological Nutrient Removal From Municipal And Industrial Wastewater Using A Twin Circulating Fluidized Bed Bioreactor, Mehran Andalib Apr 2011

Biological Nutrient Removal From Municipal And Industrial Wastewater Using A Twin Circulating Fluidized Bed Bioreactor, Mehran Andalib

Electronic Thesis and Dissertation Repository

Biological nutrient removal (BNR) refers to removal of carbon (C), nitrogen (N) and phosphorus (P) from wastewater (WW) by the aid of various microorganisms. Because of the public concern for the environment C, N and P effluent standards have become stricter. Different BNR processes such as suspended growth and attached growth have been studied during the last three decades in order to meet the increasingly stringent discharge standards.

In this work, two novel processes called Twin Fluidized Bed Bioreactor (TFBBR) and Twin Circulating Fluidized Bed Bioreactor (TCFBBR) were developed and tested for BNR from municipal WW. Both TFBBR and TCFBBR ...


Image-Guided Robot-Assisted Techniques With Applications In Minimally Invasive Therapy And Cell Biology, Mahdi Azizian Apr 2011

Image-Guided Robot-Assisted Techniques With Applications In Minimally Invasive Therapy And Cell Biology, Mahdi Azizian

Electronic Thesis and Dissertation Repository

There are several situations where tasks can be performed better robotically rather than manually. Among these are situations (a) where high accuracy and robustness are required, (b) where difficult or hazardous working conditions exist, and (c) where very large or very small motions or forces are involved. Recent advances in technology have resulted in smaller size robots with higher accuracy and reliability. As a result, robotics is fi nding more and more applications in Biomedical Engineering. Medical Robotics and Cell Micro-Manipulation are two of these applications involving interaction with delicate living organs at very di fferent scales.
Availability of a ...


Evaluation Of Wind-Induced Resuspension On The Performance Of A Mine Tailings Storage Facility, Laxmi Kant Kachhwal Apr 2011

Evaluation Of Wind-Induced Resuspension On The Performance Of A Mine Tailings Storage Facility, Laxmi Kant Kachhwal

Electronic Thesis and Dissertation Repository

Proper management of sulphide rich reactive mine tailings is a growing concern for mining industries. Oxidation of tailings can release acids and toxic metals into the surroundings, which can potentially pollute the ecosystem. Confining tailings under shallow water covers is one of the most successfully applied technologies for long-term storage. The water has lower solubility and diffusivity of oxygen than air and can significantly reduce the influx of oxygen to the bed tailings. However, wind-induced waves and currents in the water can resuspend bed tailings and ultimately result in oxidation.

Extensive field investigations were carried out to evaluate the performance ...


Optical-Wimax Hybrid Networks, Abdou R. A. Ahmed Apr 2011

Optical-Wimax Hybrid Networks, Abdou R. A. Ahmed

Electronic Thesis and Dissertation Repository

The emergence of bandwidth-intensive Internet services, such as
circuit-quality voice transfer and interactive video gaming, create
a high demand for a very qualified next-generation access network.
In addition to high bandwidth, these future access networks should
also provide improved network availability, flexibility, mobility,
reliability, failure protection, quality of service (QoS) support
and cost-effective access. The integration between optical networks
and Worldwide Interoperability for Microwave Access (WiMAX) is a
promising solution for future access networks. Accordingly, a few
different architectures and MAC protocol components have recently
been proposed for the integration between the Ethernet Passive
Optical Network (EPON) and WiMAX. However ...


Investigation Of Ash Deposition During Co-Firing Biomass/Peat With Coal In A Pilot-Scale Fluidized-Bed Reactor, Yuanyuan Shao Apr 2011

Investigation Of Ash Deposition During Co-Firing Biomass/Peat With Coal In A Pilot-Scale Fluidized-Bed Reactor, Yuanyuan Shao

Electronic Thesis and Dissertation Repository

Biomass, a promising alternative to fossil fuels, has been applied widely for energy generation by co-firing technology in recent year particularly in the EU countries. In this thesis, a key issue of biomass co-firing technology - ash deposition in combustion, co-combustion and gasification, was comprehensively investigated in a pilot-scale bubbling fluidized bed reactor. A custom-designed, air-cooled probe was installed in the freeboard zone of the reactor to simulate the heat-transfer surface and collect ash deposits from the process. A local lignite coal, a woody biomass (white pine), and a Canadian peat were involved in the tests. The main varying operating parameters ...


Impact Of Geomagnetically Induced Currents On Power Transformers, Jonathan E. Berge Apr 2011

Impact Of Geomagnetically Induced Currents On Power Transformers, Jonathan E. Berge

Electronic Thesis and Dissertation Repository

This thesis deals with the impact of Geomagnetically Induced Current (GIC) on power transformers in electrical power systems. A simulator to calculate the flows of GIC in an electrical power network, based on an assumed or measured induced geoelectric potential is proposed. This simulator includes all needed mapping techniques to handle a system that cover a large geographical area.

A correlation between GIC and the reactive power absorbed in the core of the saturated transformer is proposed. That correlation is used to estimate GIC in a transformer utilizing existing reactive power measuring infrastructure within the electrical grid without the need ...


Control And Power Supply For Resistance Spot Welding (Rsw), Meranda Salem Apr 2011

Control And Power Supply For Resistance Spot Welding (Rsw), Meranda Salem

Electronic Thesis and Dissertation Repository

In the automobile industry, Resistance Spot Welding (RSW) is widely used for its low cost, high speed, simple mechanism and applicability for automation. RSW has become the predominant means of auto body assembly, resulting in two to six thousands spot welds performed on each manufactured car. In the North American automobile industry there are approximately 100 billion spot welds, which are done every year.

RSW is the joining of two or more metal parts together in a localized area by resistive heating and pressure. Small Scale RSW (SSRSW) is commonly used for medical devices and electronic components, because the welded ...


The Behaviour Of Cement Stabilized Clay At High Water Contents, Saeed Sasanian Mar 2011

The Behaviour Of Cement Stabilized Clay At High Water Contents, Saeed Sasanian

Electronic Thesis and Dissertation Repository

Artificial cementation of soft clays has been used for several years for different ground improvement projects. Although considerable work has been done to develop advanced machinery and techniques for the implementation of artificial cementation, less knowledge is available on the mechanisms involving the formation of the artificial structure and the resulting mechanical behaviour. The primary objectives of the present work were to investigate the formation of microstructure in artificially cemented material with Portland cement, find the relationships between cementitious bonding and clay mineralogy, and create constitutive frameworks for predicting the mechanical behaviour of cement-treated clays.

Qualitative and quantitative microstructural characterisation ...


Advances In Internal Model Principle Control Theory, Jin Lu Feb 2011

Advances In Internal Model Principle Control Theory, Jin Lu

Electronic Thesis and Dissertation Repository

In this thesis, two advanced implementations of the internal model principle (IMP) are presented. The first is the identification of exponentially damped sinusoidal (EDS) signals with unknown parameters which are widely used to model audio signals. This application is developed in discrete time as a signal processing problem. An IMP based adaptive algorithm is developed for estimating two EDS parameters, the damping factor and frequency. The stability and convergence of this adaptive algorithm is analyzed based on a discrete time two time scale averaging theory. Simulation results demonstrate the identification performance of the proposed algorithm and verify its stability.

The ...


Synthesis Of One-Dimensional And Two-Dimensional Carbon Based Nanomaterials, Mihnea Ioan Ionescu Feb 2011

Synthesis Of One-Dimensional And Two-Dimensional Carbon Based Nanomaterials, Mihnea Ioan Ionescu

Electronic Thesis and Dissertation Repository

Particular physical and chemical properties of carbon based nanomaterials (CBNs) have promised and exhibited great applications in manufacturing various nanodevices such as electron field emitters, sensors, one-dimensional conductors, supercapacitors, reinforcing fibres, hydrogen storage devices, and catalyst support for fuel cells electrodes. Despite these amazing technical progresses, many challenges still remain in the development of synthesis methods suitable for commercial applications and fabricating novel functional nanostructures with complex architecture.

In this Ph.D. thesis, one-dimensional (1D), two-dimensional (2D) carbon nanostructures, and 1D/2D hybrid of carbon nanostructures have been synthesized using various chemical vapour deposition (CVD) methods. The objective of this ...


Development Of An Active Elbow Motion Simulator And Coordinate Systems To Evaluate Kinematics In Multiple Positions, Louis M. Ferreira Jan 2011

Development Of An Active Elbow Motion Simulator And Coordinate Systems To Evaluate Kinematics In Multiple Positions, Louis M. Ferreira

Electronic Thesis and Dissertation Repository

Elbow disorders are common as a consequence of both traumatic and degenerative conditions. Relative to disorders of the lower limb, there is comparatively little evidence to direct the treatment of many elbow disorders. Biomechanical studies are required to develop and validate the optimal treatment of elbow disorders prior to their application in patients. Clinically relevant simulation of elbow motion in the laboratory can be a powerful tool to advance our knowledge of elbow disorders. This work was undertaken with the rationale that simulation and quantification of elbow motion could be improved significantly. This treatise includes the development and evaluation of ...


Numerical Simulation Of Tornado-Like Vortices, Diwakar Natarajan Jan 2011

Numerical Simulation Of Tornado-Like Vortices, Diwakar Natarajan

Electronic Thesis and Dissertation Repository

The thesis investigates by numerical simulation the flow characteristics of tornado like vortices produced by three types of vortex generators, namely, Ward-type Tornado Vortex Chamber (TVC), WinDEEE Dome and Atmospheric Vortex Engine (AVE).

Laboratory scale (Ward-type TVC) tornado-like vortices were simulated for swirl ratios 0.1 to 2.0 using the CFD code Fluent 6.3. The simulations with Reynolds stress model compare well with past experimental results. Multiple vortices were observed for high swirl ratios in LES simulation. These simulations have generated a comprehensive benchmark data for future modelers and experimenters.

The effects of translation and surface roughness on ...


A Usability Maturity Model For Open Source Software, Arif Raza Jan 2011

A Usability Maturity Model For Open Source Software, Arif Raza

Electronic Thesis and Dissertation Repository

User satisfaction has always been a major factor in the success of software, regardless of whether the software is closed proprietary or open source software (OSS). Although user-centered designs are gaining recognition among the OSS community, many design scenarios still do not incorporate usability as one of their primary goals. Accordingly, many individuals believe that if OSS was more usable, its popularity would increase tremendously. Although there are strong examples of usable open source software, there is still potential to improve the usability of OSS. The usability assessment of open source projects is an area where relatively little research has ...


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 ...


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 ...


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 ...


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 ...