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Full-Text Articles in Engineering

Impact Of Bioparticle Recirculation In A Circulating Fluidized Bed Biofilm Reactor On Simultaneous Organic And Nitrogen Removal, Ming Li Dec 2012

Impact Of Bioparticle Recirculation In A Circulating Fluidized Bed Biofilm Reactor On Simultaneous Organic And Nitrogen Removal, Ming Li

Electronic Thesis and Dissertation Repository

The Circulating Fluidized Bed Biofilm Reactor (CFBBR), a bioparticle technology designed for biological nutrient removal, has been implemented to achieve considerable biodegradation efficiency and low sludge production, compared with activated sludge system and typical biofilm technology. The inherent advantages of bioparticle technology are enhanced substantially by the CFBBR, for example, decoupling of hydraulic retention time (HRT) from solids retention time (SRT), large specific surface area, ideal conditions for biofilm ecosystem.

In this work, bioparticle recirculation, as a novel control method for bioparticle system, was demonstrated in CFBBRs. To verify the impact of bioparticle recirculation on the reactor performance, bio-kinetics and …


Passive And Semi-Active Structure-Multiple Tuned Liquid Damper Systems, Islam Soliman Dec 2012

Passive And Semi-Active Structure-Multiple Tuned Liquid Damper Systems, Islam Soliman

Electronic Thesis and Dissertation Repository

The resonant vibration motion of tall buildings due to dynamic loading, such as wind storms and earthquakes, can be reduced by adding passive dynamic vibration absorbers (DVAs). A single sway mode of vibration is usually considered, however, for certain structures, multiple modes may need to be suppressed. Furthermore, the location of the TLD on the floor plate is important for certain modes, such as the torsional mode. As a result, a three dimensional finite element structure-TLD system model capable of dynamically analyzing a 3D structure is developed and validated. Two different nonlinear TLD models are considered. A full dynamic analysis …


Topographic Influences On Trends And Cycles In Nutrient Export From Forested Catchments On The Precambrian Shield, Samson G. Mengistu Dec 2012

Topographic Influences On Trends And Cycles In Nutrient Export From Forested Catchments On The Precambrian Shield, Samson G. Mengistu

Electronic Thesis and Dissertation Repository

This dissertation explored topographic controls on spatial and temporal patterns in water yield and nutrient (carbon, nitrogen and phosphorus) export from forested headwater catchments in the Turkey Lakes Watershed in central Ontario, where other factors contributing to differences in water yield and nutrient export, including climate, geology, forest, and soils, are relatively constant. Topographic characteristics, including (a) hydrological flushing potential (expansion of water table into nitrate-N producing areas); (b) hydrological storage potential (area of wetlands, which can alternatively allow water and nutrients to bypass wetlands when storage capacity is filled with water or to trap them when not filled); and …


Wind Field Measurements Around Photovoltaic Panel Arrays Mounted On Large Flat-Roofs, R Nicolas Pratt Dec 2012

Wind Field Measurements Around Photovoltaic Panel Arrays Mounted On Large Flat-Roofs, R Nicolas Pratt

Electronic Thesis and Dissertation Repository

An investigation of the wind field around roof-mounted PV arrays has been undertaken, utilizing synchronized TR-PIV and pressure measurements, in order to better understand the mechanisms which result in the aerodynamic loads, most importantly uplift, which act on such arrays. The mean flow is not significantly altered above the array as compared to a bare roof, while Reynolds normal and shear stresses are markedly reduced. Increasing the tilt angle of the array results in a progression from uplifts driven by vortex induced suction, which cause peak uplifts on a bare roof, towards uplifts which are driven primarily by local flow …


Monotonic And Cyclic Behaviour Of Steel Fibre-Reinforced And Frp-Steel Fibre-Reinforced Helical Pulldown Micropiles, Mahmoud Meckkey M. El Sharnouby Oct 2012

Monotonic And Cyclic Behaviour Of Steel Fibre-Reinforced And Frp-Steel Fibre-Reinforced Helical Pulldown Micropiles, Mahmoud Meckkey M. El Sharnouby

Electronic Thesis and Dissertation Repository

Helical piles are a deep foundation system that can be used to support pipelines, telecommunication and transmission towers, and low- and medium-rise buildings. Advantages of helical piles include: short installation time with minimal noise and vibration levels; can be installed with ease in limited accessibility site; and onsite quality control by measurement of installation torque.

The main objective of the current research is to assess the performance of steel fibre-reinforced helical pulldown micropiles (RHPM), and fibre-reinforced polymer-steel fibre- reinforced pulldown micropiles (FRP-RHPM) under axial and lateral monotonic and cyclic loading conditions.

The research methodology involved conducting full scale field testing …


Comparison Between Three Types Of Cable Stayed Bridges Using Structural Optimization, Olfat Sarhang Zadeh Oct 2012

Comparison Between Three Types Of Cable Stayed Bridges Using Structural Optimization, Olfat Sarhang Zadeh

Electronic Thesis and Dissertation Repository

Cable stayed bridges have good stability, optimum use of structural materials, aesthetic, relatively low design and maintenance costs, and efficient structural characteristics. Therefore, this type of bridges are becoming more and more popular and are usually preferred for long span crossings compared to suspension bridges. A cable-stayed bridge consists of one or more towers with cables supporting the bridge deck. In terms of cable arrangements, the most common type of cable stayed bridges are fan, harp, and semi fan bridges. Because of their large size and nonlinear structural behaviour, the analysis of these types of bridges is more complicated than …


Load-Sharing Of Toe-Nailed, Roof-To-Wall Connections Under Extreme Wind Loads In Wood-Frame Houses, Mohammad Khan Oct 2012

Load-Sharing Of Toe-Nailed, Roof-To-Wall Connections Under Extreme Wind Loads In Wood-Frame Houses, Mohammad Khan

Electronic Thesis and Dissertation Repository

A typical wood frame house roof consists of trusses which are nailed to the top-plates of the wall assembly. These are known as roof-to-wall connections (RTWCs). A load-sharing mechanism is developed between adjacent RTWCs via roof elements such as roof-sheathing, fascia beams, etc., during high wind loads. An experimental setup was developed to observe the load-sharing behavior between seven connections. To mimic the roof bending stiffness in the direction perpendicular to the trusses, two steel beams with representative bending stiffness were connected across the RTWCs in a simple way. Identical ramp and identical fluctuating wind loads were applied to all …


Electrokinetic Dewatering Of Oil Sands Tailings, Yu Guo Sep 2012

Electrokinetic Dewatering Of Oil Sands Tailings, Yu Guo

Electronic Thesis and Dissertation Repository

Oil sands tailings are the final product of oil sands processing and in the form of slurry with very low solid content. After sedimentation, due to a low hydraulic conductivity of the tailings, both dewatering and consolidating the tailings are difficult. Since electrokinetic (EK) is an effective method to consolidate low permeability soils, the objective of this study is to assess the effectiveness and efficiency of EK dewatering of MFT, a man-made geomaterial. Two series of tests were conducted in this study. In the first series, four EK cell tests were performed on oil sands tailings to measure the electroosmotic …


Influence Of Oceanic Forcing On Fate Of Nutrients In A Near-Shore-Aquifer, Nawrin Anwar Aug 2012

Influence Of Oceanic Forcing On Fate Of Nutrients In A Near-Shore-Aquifer, Nawrin Anwar

Electronic Thesis and Dissertation Repository

A reactive groundwater transport model has been developed to investigate the fate of nutrients (ammonium, nitrate, and phosphate) in a near-shore coastal aquifer subject to oceanic forcing (tides and waves) and their subsequent discharge to coastal waters. The model is developed by combining the variable-density groundwater flow model SEAWAT-2005 with the reactive multi-component transport model PHT3D v2.10. The influence of tides and waves are typically neglected in prior studies that have examined the transport and transformation of nutrients in coastal aquifers. Oceanic forcing however can induce a highly dynamic surficial salt-freshwater mixing and reaction zone in a near-shore aquifer and …


Improvement Of Total Sulphur Measurement Techniques For Management Of Reactive Mine Tailings, Adnan Hossain Khan Aug 2012

Improvement Of Total Sulphur Measurement Techniques For Management Of Reactive Mine Tailings, Adnan Hossain Khan

Electronic Thesis and Dissertation Repository

A sample preparation method for total sulphur measurement in reactive mine tailings was developed by ultrasound assisted digestion (USAD) and inductively coupled plasma-optical emission spectroscopy (ICP-OES) technique. KZK-1, asericite schist, was selected as the certified reference material (CRM) and Musselwhite gold mine tailings were used as tailings sample. Experimental factors (i.e. digestion time, temperature and acid-oxidant combination) were studied in two steps. In the first step, a two-level and three-factor (23) full factorial design of experiment was applied and the total sulphur was measured by USAD and ICP-OES technique. The best result at 95% confidence level (P …


Water Treatment Using Advanced Oxidation Processes: Application Perspectives, Charles R. Gilmour Aug 2012

Water Treatment Using Advanced Oxidation Processes: Application Perspectives, Charles R. Gilmour

Electronic Thesis and Dissertation Repository

Advanced oxidation processes (AOPs) using hydroxyl radicals and other oxidative radical species are being studied extensively for removal of organic compounds from various waste streams. However, large scale applications of these highly effective technologies in water and wastewater treatment are still very limited due to cost and inadequate information about the resultant water quality. This study focuses on the evaluation of the upstream processing and downstream post treatment analysis of selective AOPs. In the first stage of research, the performance of a proprietary catalyst (VN-TiO2) was compared with the industry standard P25 TiO2, for the use …


Flexural Behaviour Of Steel Fibre Reinforced Concrete Tunnel Linings, Martin Blazejowski Aug 2012

Flexural Behaviour Of Steel Fibre Reinforced Concrete Tunnel Linings, Martin Blazejowski

Electronic Thesis and Dissertation Repository

The promotion of steel fibre reinforced concrete (SFRC) as a construction material for tunnel linings has prompted a number of researchers to focus on methods of evaluating their flexural strength and stiffness. This thesis presents the results of an experimental and numerical investigation of the flexural behaviour of full-scale steel fibre reinforced concrete tunnel lining segments. A series of a three-point flexure tests were performed to evaluate the maximum load carrying capacity, the load-deformation behaviour and crack propagation characteristics of these segments. The material properties of the steel fibre reinforced concrete were also studied, using both destructive and non-destructive methods. …


Analytical And Experimental Study Of A Three Dimensional Internal Hydraulic Jump In A Shallow Channel Of Limited Width, Zoheb Nasir Aug 2012

Analytical And Experimental Study Of A Three Dimensional Internal Hydraulic Jump In A Shallow Channel Of Limited Width, Zoheb Nasir

Electronic Thesis and Dissertation Repository

The main objective of this thesis is to study the hydraulic behaviour of a surface heated discharge in a shallow channel, which is wider than the discharge of thermal waste, and connected to a colder water body. An internal hydraulic jump characterized by mixing (dilution) of hot and cold water was observed in the channel. Similar to the single-layer hydraulic jump, the internal hydraulic jump in a two-layer system is a rapid transition from supercritical to subcritical flow.

The study involved analytical and experimental analyses of the flow in the channel. The analytical analysis showed that the critical dilution initially …


Disinfection Of Low Uv Transmittance Fluids: Fundamentals And Applications, Housyn Mahmoud Aug 2012

Disinfection Of Low Uv Transmittance Fluids: Fundamentals And Applications, Housyn Mahmoud

Electronic Thesis and Dissertation Repository

Modern consumer demands for tasty, safe and healthier liquid foods and beverages. Chemical preservatives are usually added to foods to extend their shelf life and to protect against food borne pathogens. Application of ultraviolet (UV) light is gaining more attention as an alternative technology to disinfect fluids with low UV transmittance replacing classical chemical or thermal procedures due to growing negative public reaction over chemicals added. UV light irradiation has a positive consumer image as it is a physical non-thermal method efficient against microbial hazards, chemicals free cost effective and energy efficient methods and has been approved by regulatory agencies. …


Experimental & Empirical Correlations For The Determination Of The Overall Volumetric Mass Transfer Coefficients Of Carbon Dioxide In Stirred Tank Bioreactors, Syeda Anam Kazim Aug 2012

Experimental & Empirical Correlations For The Determination Of The Overall Volumetric Mass Transfer Coefficients Of Carbon Dioxide In Stirred Tank Bioreactors, Syeda Anam Kazim

Electronic Thesis and Dissertation Repository

One of the most important parameters to cultivate microalgae is carbon dioxide absorption by microalgae. Therefore, it is necessary to determine the overall volumetric mass transfer coefficient (KLa) of carbon dioxide to quantify CO2 transfer from the gaseous to the liquid phase. Until now, finding KLa of CO2 for microalgae cultivation has been a challenge as there is not much information available about it in the literature and most of the time the CO2 transfer to microalgae is approximated. In this study, correlations to directly calculate KLa of CO2 in …


Thermal And Electrical Behaviors Of Selected Geomaterials, Joon Kyu Lee Aug 2012

Thermal And Electrical Behaviors Of Selected Geomaterials, Joon Kyu Lee

Electronic Thesis and Dissertation Repository

Geomaterials can be often classified into two groups: virgin geomaterials such as soil and rock, and by-product materials such as mine tailings, coal fly/bottom ash, foundry sand, kiln dust, blast furnace/steel slag, reclaimed concrete and asphalt. Studies on these materials and their mixtures have been carried out extensively for geoengineering applications, including the characterization of mechanical properties such as the strength, compressibility, compactivity and permeability, as well as mineralogical and geochemical properties. The goal of this study is to investigate the thermal and electrical properties of selected geomaterials and their mixtures for enhancement of knowledge and engineering applications. The thesis …


Solar And Visible Light Driven Photocatalysis For Sacrificial Hydrogen Generation And Water Detoxification With Chemically Modified Ti02, Pankaj Chowdhury Aug 2012

Solar And Visible Light Driven Photocatalysis For Sacrificial Hydrogen Generation And Water Detoxification With Chemically Modified Ti02, Pankaj Chowdhury

Electronic Thesis and Dissertation Repository

Photocatalysis is a recognized approach where light energy is employed to excite the semiconductor material producing electron/hole pair which eventually involves in the detoxification of pollutants and/or water splitting producing hydrogen. Existing photocatalysts suffer from poor activity or no activity in visible light irradiation which restricts them from solar light utilization. This work is focused on two key applications of photocatalysis (i) sacrificial hydrogen generation, and (ii) phenol degradation in visible and/or solar light. Platinum was loaded on TiO2 photocatalyst by solar photo-deposition method. Eosin Y dye was used as a sensitizer for sensitization of platinum loaded TiO2 …


An Investigation Of Monotonic And Cyclic Behaviour Of Leda Clay, Kimberly K. Rasmussen Jul 2012

An Investigation Of Monotonic And Cyclic Behaviour Of Leda Clay, Kimberly K. Rasmussen

Electronic Thesis and Dissertation Repository

The behaviour of a sensitive clay from Ottawa is investigated though strain- and stress-controlled cyclic simple shear, and resonant column tests. Strain-controlled tests were performed at frequencies 0.1 to 10Hz, and amplitudes 0.1% to 5%. Over this range of strain amplitudes there are large drops in stiffness. Strain amplitude has a greater effect on the generation of pore-pressures than frequency. Stress-controlled tests performed at a yield stress ratio of 1 had higher strength at low N but degraded more readily than a test at YSR =2. A novel method of remoulding clay and measuring the remoulding energy is also presented. …


Response Of Foundations To Random Cyclic Loads, Alireza Varshoi Jul 2012

Response Of Foundations To Random Cyclic Loads, Alireza Varshoi

Electronic Thesis and Dissertation Repository

Variable amplitude cyclic loads due to natural phenomena are common for laterally loaded piles. A series of small scale cyclic model test have been performed in the Boundary Layer Wind Tunnel Laboratory. Random loads from a boundary layer wind field were applied to a model consisting of a pile, pole and plate. The same setup was also tested under static conditions for comparison. Hyperbolic projection was used to represent the load – displacement relations. Initial stiffness and hyperbolic capacity were obtained from this method. The number of load cycles was found to affect the behavior of the laterally loaded piles. …


Bayesian Analyses Of Metal-Loss Corrosion On Energy Pipeline Based On Inspection Data, Mohammad Al-Amin Jun 2012

Bayesian Analyses Of Metal-Loss Corrosion On Energy Pipeline Based On Inspection Data, Mohammad Al-Amin

Electronic Thesis and Dissertation Repository

Bayesian models are developed to calibrate the accuracies of high-resolution in-line inspection (ILI) tools for sizing metal-loss corrosion defects and to characterize the growth of individual defects on energy pipelines. Moreover, a methodology is proposed to evaluate the time-dependent system reliability of a segment of a pressurized pipeline containing multiple active corrosion defects. The calibration of ILI tools is carried out by comparing the field-measured depths and ILI-reported depths for a set of static defects. The proposed methodology is able to quantify the measurement errors of multiple ILI tools simultaneously and evaluate the correlation between random errors associated with different …


Consistent Density Scanning And Information Extraction From Point Clouds Of Building Interiors, Kuldeep Kumar Sareen Jun 2012

Consistent Density Scanning And Information Extraction From Point Clouds Of Building Interiors, Kuldeep Kumar Sareen

Electronic Thesis and Dissertation Repository

Over the last decade, 3D range scanning systems have improved considerably enabling the designers to capture large and complex domains such as building interiors. The captured point cloud is processed to extract specific Building Information Models, where the main research challenge is to simultaneously handle huge and cohesive point clouds representing multiple objects, occluded features and vast geometric diversity. These domain characteristics increase the data complexities and thus make it difficult to extract accurate information models from the captured point clouds.

The research work presented in this thesis improves the information extraction pipeline with the development of novel algorithms for …


Performance Of Hollow Bar Micropiles Under Axial And Lateral Loads In Cohesive Soils, Ahmed Yehia Abd El-Aziz Jun 2012

Performance Of Hollow Bar Micropiles Under Axial And Lateral Loads In Cohesive Soils, Ahmed Yehia Abd El-Aziz

Electronic Thesis and Dissertation Repository

The use of hollow core bars in micropiles has greatly increased over the past ten years. Hollow core construction, also known as “self drilled”, is becoming a popular option because it allows a faster installation processes and ground improvement at the same time. Despite the growing demand for hollow bar micropiles, little work has been devoted to evaluating the nominal bond strength between the micropile grout and the surrounding soil, especially in clayey soils. Moreover, the performance of such micropiles under different kinds of loading is still largely unknown and needs to be investigated.

In this study, a research methodology …


Synergistic And Environmental Benefits Of Using Cement Kiln Dust With Slag And Fly Ash In Cemented Paste Tailings, Amajd Tariq May 2012

Synergistic And Environmental Benefits Of Using Cement Kiln Dust With Slag And Fly Ash In Cemented Paste Tailings, Amajd Tariq

Electronic Thesis and Dissertation Repository

Many researchers have validated the phenomenon of internal sulphate attack in ordinary Portland cement (CSA Type GU) based cemented paste tailings containing sulphide minerals and have observed secondary gypsum as an ubiquitous phase in such matrices. The secondary gypsum, due to its soft nature and swelling and expansive properties, is principally considered to be the sole culprit responsible for subsequent internal cracking and strength degradation of sulphidic paste at later stages. High Portland cement cost and its apparent poor performance in the long-term in sulphate rich environments advocate for the formulation of resilient cemented paste tailings using economical but efficient …


A Study On The Turbulent Characteristics Within The Hurricane Boundary Layer, Sunwei Li May 2012

A Study On The Turbulent Characteristics Within The Hurricane Boundary Layer, Sunwei Li

Electronic Thesis and Dissertation Repository

As the medium between the sea surface and the upper atmosphere in a hurricane, the Hurricane Boundary Layer (HBL) plays a key role in the overall dynamics of a tropical cyclone, and therefore turbulence exchanges within the HBL deserve a thorough investi- gation. However, since it is dangerous and difficult to take direct measurements within the HBL, studies of the HBL turbulence processes based on direct observations are rare. Thanks to the newly developed dropwindsonde equipped with a Global Position System (GPS) receiver, it is now possible to measure wind velocities and other meteorological variables with an unprecedented accuracy and …


Fuzzy Differential Evolution Algorithm, Dejan Vucetic May 2012

Fuzzy Differential Evolution Algorithm, Dejan Vucetic

Electronic Thesis and Dissertation Repository

The Differential Evolution (DE) algorithm is a powerful search technique for solving global optimization problems over continuous space. The search initialization for this algorithm does not adequately capture vague preliminary knowledge from the problem domain. This thesis proposes a novel Fuzzy Differential Evolution (FDE) algorithm, as an alternative approach, where the vague information of the search space can be represented and used to deliver a more efficient search. The proposed FDE algorithm utilizes fuzzy set theory concepts to modify the traditional DE algorithm search initialization and mutation components. FDE, alongside other key DE features, is implemented in a convenient decision …


Enhancement Of Local Buckling Behaviour Of Steel Structures Retrofitted Through Bonding Gfrp Plates, Mohammad Al Amin Siddique Apr 2012

Enhancement Of Local Buckling Behaviour Of Steel Structures Retrofitted Through Bonding Gfrp Plates, Mohammad Al Amin Siddique

Electronic Thesis and Dissertation Repository

An effective technique involving the use of glass fiber reinforced polymer (GFRP) plates to enhance the local buckling behaviour of steel plates, beams, and moment resisting frames is presented in this Thesis. The enhancement in buckling capacity is achieved by bonding GFRP plates to the steel sections. These steel/GFRP joints have the advantages of ease of application, low cost, high strength-to-weight ratio, and resistance to corrosion. An interface element that simulates the behaviour of the adhesive bonding the steel and GFRP elements is developed and is implemented into an in-house developed finite element model to represent steel/GFRP joints. The model …


Investigation Of Bio-Hydrogen And Bio-Methane Production From Thin Stillage, Noha El-Sayed Nasr Apr 2012

Investigation Of Bio-Hydrogen And Bio-Methane Production From Thin Stillage, Noha El-Sayed Nasr

Electronic Thesis and Dissertation Repository

An evaluation of single-stage and two-stage anaerobic digestion processes for biomethane and biohydrogen production using thin stillage was performed to assess the viability of biohydrogen production from thin stillage and the impact of separating the acidogenic and methanogenic stages on anaerobic digestion with hydrogen production in the first stage. A comparative evaluation of anaerobic digester sludge (ADS) and acclimatized anaerobic digester sludge (AADS) for biohydrogen production was performed at various S°/X° ratios. The optimum range of S°/X° ratio for hydrogen production was found to be 1 to 2 gCOD/gVSS using conventional ADS and 3 to 6 gCOD/gVSS using AADS. Maximum …


Application Of A K-Nearest Neighbour Weather Generator For Simulation Of Historical And Future Climate Variables In The Upper Thames River Basin, Leanna M. King Jan 2012

Application Of A K-Nearest Neighbour Weather Generator For Simulation Of Historical And Future Climate Variables In The Upper Thames River Basin, Leanna M. King

Electronic Thesis and Dissertation Repository

Climate change has the potential to significantly alter the hydrologic cycle, changing the frequency and intensity of precipitation events in an area. It is necessary to quantify these effects to effectively manage water resources in the future. Atmosphere-Ocean coupled Global Circulation Models (AOGCMs), often used in climate change research, have spatial resolutions that are too large to capture the local climate characteristics of a watershed. As a result, several downscaling tools have been developed, including stochastic weather generators. A methodology for the simulation of historical and future climate data using a nonparametric K-Nearest Neighbour block resampling weather generator with perturbation …