Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Theses

Discipline
Institution
Keyword
Publication Year
Publication Type

Articles 571 - 600 of 3460

Full-Text Articles in Engineering

A Methodology To Consolidate Transit Stops For Enhancing Transit Users Travel Times, Mohammad Nurul Hassan Jan 2013

A Methodology To Consolidate Transit Stops For Enhancing Transit Users Travel Times, Mohammad Nurul Hassan

Theses

This study develops a methodology to consolidate transit stops. It develops a mathematical model and a program which takes stop consolidation decision(s) according to users travel time savings and desired accessibility. The model iterates until the users travels time savings are maximized. The study tests this mathematical model in different hypothetical scenarios. Six factors (distance between stops, passengers’ activity, average cruising speed, and maximum walkable distance, frequency of service and percentage of decreased passengers) with multiple levels were set to build the scenarios. Three responses (percentage of consolidated stops, percentage of travel time savings and percentage of operating …


Investigation Of The Mechanical Behavior Of I-Shaped Steel Beams Strengthened By Mechanically-Fastened Frp Laminates, Hothifa Nayef Rojob Jan 2013

Investigation Of The Mechanical Behavior Of I-Shaped Steel Beams Strengthened By Mechanically-Fastened Frp Laminates, Hothifa Nayef Rojob

Theses

Retrofitting and strengthening of steel structures have gained significant importance due to the highly increasing number of deteriorated steel structures in many places around the globe. The conventional method of retrofitting or strengthening of steel structures by replacing steel members or attaching additional external steel plates are usually time-consuming, corrodible, and a cumbersome task. Many of the drawbacks of the conventional retrofitting systems can be overcome through the use of Fiber Reinforced Polymers (FRP) due to their high strength-to-weight ratio. Furthermore, FRP materials are corrosion resistant, which makes them more durable especially when environmental deterioration is a concern. In recent …


Effect Of Microwave Heating On The Migration Of Additives From Ps, Pp And Pet Container Into Food Simulants, Ruoyin Cai Jan 2013

Effect Of Microwave Heating On The Migration Of Additives From Ps, Pp And Pet Container Into Food Simulants, Ruoyin Cai

Theses

Microwave food packaging has become a tremendous element in the food manufacturing process. The purpose of any food packaging regulations concerned with the safety of the food is to control and limit the migration of substances from the packaging into the food. The main objective of this thesis is to test three different microwaving packaging materials that are the most common material in the market, viz. polystyrene (PS), polypropylene (PP), and polyethylene terephthalate (PET), migrated into four food simulant solutions. Four different simulant solutions were used based on the food type and FDA recommendations and regulations. These food simulants include …


Subwavelength Surface Plasmons Based On Novel Structures And Metamaterials, Ruoxi Yang Jan 2013

Subwavelength Surface Plasmons Based On Novel Structures And Metamaterials, Ruoxi Yang

Theses

With the rapid development of nanofabrication technology and powerful computational tools over the last decade, nanophotonics has enjoyed tremendous innovation and found wide applications in ultrahigh-speed data transmission, sensitive optical detection, manipulation of ultra-small objects, and visualization of nanoscale patterns. Surface plasmon-based photonics (or plasmonics) merges electronics and photonics at the nanoscale, creating the ability to combine the superior technical advantages of photonics and electronics on the same chip. Plasmonics focuses on the innovation of photonic devices by exploiting the optical property of metals. In particular, the oscillation of free electrons, when properly driven by electromagnetic waves, would form plasmon-polaritons …


Effects Of Openings On The Analysis And Design Of Precast Prestressed Hollow Core Slabs, Eoghan Lodge Jan 2013

Effects Of Openings On The Analysis And Design Of Precast Prestressed Hollow Core Slabs, Eoghan Lodge

Theses

Precast prestressed hollow core floors are a widely used structural element which offers increased speed of construction, reduced self-weight and many other advantages. Due to the relatively low span-to-depth ratio and the speed of construction hollow core slabs are utilised in a large number of commercial buildings. In order to carry the services to the upper floors an opening must be made within the prestressed slab. Cutting an opening in a prestressed slab has significant effects on the structural behaviour of the slab and can considerably reduce the ultimate capacity of the slab.

This paper outlines the limited available guidance …


Reinforced Concrete Deterioration Of A 100 Year Old Structure In A Marine Environment, Ross O'Donovan Jan 2013

Reinforced Concrete Deterioration Of A 100 Year Old Structure In A Marine Environment, Ross O'Donovan

Theses

The current study investigates the deterioration of a 100 year old bridge located in a harsh marine environment. Constructed in 1908 - 1909 the Mizen Head Footbridge was one of the oldest reinforced concrete bridges in Ireland. The demolition of the bridge in 2009 provided a unique opportunity to examine its service life and to extract samples for analysis and investigation. A review of the construction of the bridge, and its maintenance history are presented, with a view to analysing their influence on the behaviour of the concrete.

Reinforcement corrosion due to chloride attack was identified. A focused study indicates …


An Examination Of The Influence Of Pressure Management And Active Leakage Control In Establishing The Economic Level Of Leakage For An Urban Water Operational Area, Mark Callanan Jan 2013

An Examination Of The Influence Of Pressure Management And Active Leakage Control In Establishing The Economic Level Of Leakage For An Urban Water Operational Area, Mark Callanan

Theses

Leakage targets in Ireland are based on the Unaccounted for Water (UFW) performance indicator. This has been set out in the National Water Study published by the Department of Environment, Community and Local Government (DECLG) in 2000. This leakage target performance indicator has been maintained since in all government published reports and guidelines.

The use of this performance indicator has been discouraged by the International Water Association (IWA) and its use has been discontinued by the UK water industry because it can misrepresent the true level of leakage. The IWA recommends the use of the Infrastructure Leakage Index (ILl) as …


Investigation Of Wastewater Treatment Plant Sustainability Potential In Terms Of Resource Recovery Essentials, Aoife Moloney Jan 2013

Investigation Of Wastewater Treatment Plant Sustainability Potential In Terms Of Resource Recovery Essentials, Aoife Moloney

Theses

This thesis aims to explore the sustainability potential which exists in Wastewater Treatment Plants (WWTP's); particularly focusing on nutrient, energy, and water recovery and reuse. The core of the research will focus on the establishment of a sustainable Resource Recovery Treatment Plant (RRTP) plan for Limerick Main Drainage (LMD) WWTP, and potentially utilising this as a case study plant which could act as a foundation example within the sector.

There is a genuine need to investigate more sustainable options in wastewater treatment (WWT); increasing energy and sludge management costs are a real issue for non-sustainable WWTP's given that thousands of …


A Common Methodology To Assess The Sustainability Of Different Stages Of The Water Cycle In An Urban Environment In An Irish Context, Áine Mcgrath Jan 2013

A Common Methodology To Assess The Sustainability Of Different Stages Of The Water Cycle In An Urban Environment In An Irish Context, Áine Mcgrath

Theses

The project proposes to devise a common methodology to assess the sustainability of different stages of the water cycle in an urban environment in an Irish context. With the reduction in infrastructure investment by the governing bodies, the concept of sustainable development is becoming more important.

The project involves using the principals and procedures of a system analysis along with sustainable key performance indicators to assess the sustainability of water cycle system, which includes water treatment, the water distribution system, wastewater treatment and flood risk management.

A sustainability assessment of the combined stages of an urban water cycle will provide …


Preparation, Characterization And Catalytic Activity Study Of Transition Metal Doped Porous Γ-Alumina, Seham Nasser Al Hadrami Jan 2013

Preparation, Characterization And Catalytic Activity Study Of Transition Metal Doped Porous Γ-Alumina, Seham Nasser Al Hadrami

Theses

Transition-metal ions -doped γ-alumina composites with various dopant concentrations (Cr3+, Fe3+, Ce3+, Zn2+, Mn2+, V2+ and Cu2+) were prepared by straightforward tempIate-free sol-gel method. They were characterized by XRD, FTIR, SEM, NMR and N2 adsorption-desorption isotherm technique. The presence of dopant metal ions, generally, enhanced the gel formation and their behavior was dependent on the nature of the metal ion and its concentration. Certain ions, especially Fe3+, resulted in rapid formation of a transparent gel upon hydro lysis. The presence of the acetylacetonate …


Evaluation Of The Effectiveness Of Portable Variable Message Signs In Improving Safety For Motorists And Workers At Construction Zones In Abu Dhabi, Khalid Ismail Al-Zoubi Dec 2012

Evaluation Of The Effectiveness Of Portable Variable Message Signs In Improving Safety For Motorists And Workers At Construction Zones In Abu Dhabi, Khalid Ismail Al-Zoubi

Theses

In March 2008, a single accident resulted in three people being killed and nearly 350 injured in a horrific crash involving over 60 vehicles on the Abu Dhabi-Dubai highway near Ghantoot. The cause of this crash was attributed to failure by motorists to adhere to severe weather conditions (fog). In response to the increasing number of accidents on Abu Dhabi roads, the Abu Dhabi Department of Transport (DoT) has deployed approximately 40 portable Variable Message Signs (PVMSs) throughout the main DOT's highway network as one of the strategies to control driver behavior and to improve road safety. The objective of …


Pvt Study Of Selected Uae Reservoir Fluids, Rashid Sher Mohammad Dec 2012

Pvt Study Of Selected Uae Reservoir Fluids, Rashid Sher Mohammad

Theses

Phase behavior modeling in crude oil includes prediction of thermodynamic properties (such as saturation pressure, density, viscosity, thermal conductivity, etc.) for the vapor and liquid phases. The aim of phase behavior modeling is to establish the accuracy and reliability of the developed equation of state model to predict various other fluid phase behavior properties at high pressure and temperature conditions.

In the first part of this work, a new and reliable phase behavior apparatus designed in Brazil was used for the two-stage recombination process and phase behavior measurements. The recombination of the surface sample fluids (first-stage separator gas and stock-tank …


Structural Performance And Economics Of High-Rise Buildings Under Seismic And Wind Loads, Nadeem Hussain Sep 2012

Structural Performance And Economics Of High-Rise Buildings Under Seismic And Wind Loads, Nadeem Hussain

Theses

High-rise buildings have a priority when considering the potential consequences from natural hazards since they represent concentrated human and monetary assets. The use of high strength materials is promoted in this class of structures to effectively use floor areas, control vibrations and expedite construction. There is a pressing need to investigate the relationship between structural performance and economics of high-rise buildings with different material strengths under lateral loads, particularly seismic loads that control the design of a wide range of buildings.

To realistically represent the modern high-rise construction, five 60-story reinforced concrete (RC) buildings with varying material strengths, ranging from …


Challenges Of Permitting Ballast Water Discharges From Commercial Vessels In U.S. Waters, Paul Rodriguez Aug 2012

Challenges Of Permitting Ballast Water Discharges From Commercial Vessels In U.S. Waters, Paul Rodriguez

Theses

On February 5, 2009, the US Environmental Protection Agency (US EPA) issued the Vessel General Permit (VGP), under the Clean Water Act (CWA), for discharges incidental to the normal operation of vessels, including ballast water discharges. This set forth permit requirements for most commercial vessel discharges within 3 nautical miles of U.S. shore. Since it will expire in December 2013, the US EPA recently issued a draft 2013 VGP. One of the significant changes is the proposal of numerical ballast water discharge standards requiring most commercial vessels to install ballast water treatment systems onboard.

The objective of this thesis is …


Gpu Implementation Of Block Transforms, Boyan Zhang Aug 2012

Gpu Implementation Of Block Transforms, Boyan Zhang

Theses

Traditionally, intensive floating-point computational ability of Graphics Processing Units (GPUs) has been mainly limited for rendering and visualization application by architecture and programming model. However, with increasing programmability and architecture progress, GPUs inherent massively parallel computational ability have become an essential part of today's mainstream general purpose (non-graphical) high performance computing system. It has been widely reported that adapted GPU-based algorithms outperform significantly their CPU counterpart.

The focus of the thesis is to utilize NVIDIA CUDA GPUs to implement orthogonal transforms such as signal dependent Karhunen-Loeve Transform and signal independent Discrete Cosine Transform. GPU architecture and programming model are examined. …


Optimization Of Co2 Wag Processes In A Selected Carbonate Reservoir: Laboratory Study, Mohamed Elwy Abdalla Amin Jun 2012

Optimization Of Co2 Wag Processes In A Selected Carbonate Reservoir: Laboratory Study, Mohamed Elwy Abdalla Amin

Theses

Miscible gas flooding using carbon dioxide is currently investigated as a possible EOR process for a number of United Arab Emirates (UAE) reservoirs. The major factors affecting the implementation of CO2 floods are the availability of CO2 at economic prices and the net utilization ratio of CO2 per barrel of additional oil recovered.Minimizing net utilization requires controlling the high mobility ratio which causes lower sweep. To control the mobility ratio, the Water-Alternating CO2-gas (WAG) technique is proposed.

The objective of this work is to experimentally assess the recovery of oil with CO2 injection in …


Bridgeless Step/Up Unity Power Factor Rectifier For High Voltage Applications, Aysha Kemadish Al-Kaabi Jun 2012

Bridgeless Step/Up Unity Power Factor Rectifier For High Voltage Applications, Aysha Kemadish Al-Kaabi

Theses

Power electronic devices with front- end rectifier are widely used in computer, communication and electric vehicle industries. These rectifiers are nonlinear in nature and generate current harmonics which pollute utility power. International harmonic standards (e.g., IEC 61000-3-2 and EN 61000-3-2) have been put in place to confine power pollution. These standards limit the current harmonics generated by loads to a specified threshold depending on load power and application. In other words, a high power factor is required.

Power supplies with active power factor correction (PFC) techniques are becoming necessary for many types of electronic equipment to meet the harmonic regulations …


Quantifying Prehension In Persons With Stroke Post Rehabilitation, Saumya Sara Puthenveettil May 2012

Quantifying Prehension In Persons With Stroke Post Rehabilitation, Saumya Sara Puthenveettil

Theses

This study describes the analysis of reaching and grasping abilities of the hemiparetic arm and hand of patients post stroke after a series of interactive virtual reality (VR) simulated training sessions and conventional physical therapy of similar intensity. Six subjects participated in VR training and five subjects in clinical rehabilitation for two weeks. Subjects’ finger joint angles were measured during a kinematic reach to grasp test using CyberGlove® and arm joint angles were measured using the trackSTARTM system prior to training and after training. Downward force applied to the object during grasping was assessed using Nano17TM, a force/torque sensor system …


Analysis Of Tissue Engineering Strategies For Bone-Related Applications, Timothy Buirkle May 2012

Analysis Of Tissue Engineering Strategies For Bone-Related Applications, Timothy Buirkle

Theses

Over the past few decades, tissue engineering approaches have pushed their way to the forefront of biotechnological research and development, serving a wide variety of applications. This research utilizes quantitative methods to analyze the outcome of two bone tissue engineering studies. In an in vivo study, the use of Negative Pressure Wound Therapy (NPWT) in combination with stem cell-loaded scaffolds was investigated for the repair of large bone defects. Quantitative histological analysis was performed by determining both the percentage of cells proliferating (BrdU), as well as cells expressing bone-specific markers of alkaline phosphatase (A L P) in the defect. Total …


Hydrodynamic Effects Of An Arch-Shaped Fiber Optic Probe In A Dissolution Testing Apparatus 2, Yiran Zhang May 2012

Hydrodynamic Effects Of An Arch-Shaped Fiber Optic Probe In A Dissolution Testing Apparatus 2, Yiran Zhang

Theses

Dissolution testing is widely used in the pharmaceutical industry to evaluate newly developed drug formulations and as a quality control method to insure that solid dosage forms have consistent dissolution property. Typically, samples are manually drawn from the dissolution vessel prior to analysis. An approach to overcome the limitations of manual sampling consists in the use of sampling probes, such as fiber optic probes, permanently inserted in the dissolution medium and continually sampling the drug concentration in it as the solid dosage form dissolves. Despite their advantages, permanently inserted fiber optic probes can alter the normal fluid flow within the …


Alterations In Brain Connectivity After Spinal Cord Injury Using Functional Mri, Yamin Ahmed Noor May 2012

Alterations In Brain Connectivity After Spinal Cord Injury Using Functional Mri, Yamin Ahmed Noor

Theses

Every year, approximately 50 people per million of inhabitants are inflicted by Spinal Cord Injury (SCI). The long-term impairment of the SCI patients has led researchers to investigate different rehabilitation and treatment efforts that require careful observations to be made on reliable markers. Presently, a number of neuropsychological assessments are used for SCI rehabilitation and research purposes. However, there is a need for the discovery of sensitive biomarkers that can be used to characterize SCI. Altered functional connectivity in the brain has been observed in a number of neurological patient populations. Hence, it was hypothesized that such alterations in brain …


Magnetic Targeted Drug Delivery System In Gene Therapy, Weilong Lu May 2012

Magnetic Targeted Drug Delivery System In Gene Therapy, Weilong Lu

Theses

Drug delivery system is a method to transport the drug of the required amount accurately to the targeted diseased part. Recently, the concept of Magnetic Targeted Drug Delivery System (MTDDS), based upon magnetic particles under the action of an external magnetic field, exhibits considerable potential for a wide range of medical applications. Gene therapy is the insertion of genes into an individual's cells and tissues to treat diseases. As the recombinant virus vector has many limits and problems, more studies turn to the nonvirus vectors, which have transfection efficiency and low cytotoxicity. PLLA(poly(L lactic acid)) can be biodegradable and has …


Moxon Based Rfid Tag Reader And Gps Antenna, Haojiong Liu May 2012

Moxon Based Rfid Tag Reader And Gps Antenna, Haojiong Liu

Theses

Modern communication applications at UHF frequencies require antennas with wide band, high forward gain, low backward radiation, high cross-polarization, small size and low manufacture cost. The Moxon antenna based on a two element Yagi-Uda antenna over the ground reflector is one of the most favorite antennas for HAM operators which can produce outstanding front to back ratio of radiated power, good match over the desired band and relatively low elevation height.

A sequence of topologies has been proposed from a single vertical element to two vertical elements of the Moxon arms, until the lately patented Broadband Circularly Polarized Moxon Based …


High-Performance Matrix Multiplication On Intel And Fgpa Platforms, Gang Li May 2012

High-Performance Matrix Multiplication On Intel And Fgpa Platforms, Gang Li

Theses

Matrix multiplication is at the core of high-performance numerical computation. Software methods of accelerating matrix multiplication fall into two categories. One is based on calculation simplification. The other one is based on increasing the memory access efficiency. Also matrix multiplication can be accelerated using vector processors. In this investigation, various matrix multiplication algorithms and the vector-based hardware acceleration method are analyzed and compared in terms of performance and memory requirements. Results are shown for Intel and Xilinx FPGA platforms. They show that when the CPU is fast, Goto's algorithm runs faster than Strassen's algorithm because the data access speed is …


Magnetic Iron Oxide Nanoparticles: Synthesis, Characteristics, Magnetic Behavior, And Biomedical Applications, Chengyin Fu May 2012

Magnetic Iron Oxide Nanoparticles: Synthesis, Characteristics, Magnetic Behavior, And Biomedical Applications, Chengyin Fu

Theses

Magnetic iron oxide nanoparticles are attracting increasing attention due to their interesting properties that can be applied in a great number of applications such as catalysis and biomedicine. This thesis focuses on the synthesis, characteristics, and biomedical applications of iron oxide nanoparticles. The two most common iron oxides, including magnetite and maghemite, are discussed in this thesis.

For most of their applications, the magnetic behavior of iron oxide nanoparticles in a fluid is very important, especially, the high gradient magnetic separation of the particles from a nonmagnetic liquid medium, such as blood in the human body. A 2D model, which …


Experimental Evaluation Of Near Infrared Light Penetration Into Neural Tissue, Ujwal Anil Parikh May 2012

Experimental Evaluation Of Near Infrared Light Penetration Into Neural Tissue, Ujwal Anil Parikh

Theses

Near infrared (NIR) lasers find applications in medicine both for diagnostic and treatment purposes. Penetration depth into the tissue is a critical parameter to be considered in these NIR laser applications. Published data on the optical properties of rodent neural tissue are rare, despite the frequent use of rats as animal models. The aim of this study was to directly measure the light intensity profile inside the rat brain gray matter that is illuminated by an NIR laser beam. The local light intensities were sampled using an optical fiber inserted into the brain. The intensity profile in the axial direction …


Simulation Of Polymer Solar Cell Characteristics By Amps-1d, Lu Zhang May 2012

Simulation Of Polymer Solar Cell Characteristics By Amps-1d, Lu Zhang

Theses

Simulation of polymer solar cell characteristics is presented in this study. The solar cells are made of materials such as the following: Poly (3-hexylthiophene): [6, 6]-phenyl C61- butyric acid methylester (P3HT: PCBM) and poly[2,1,3-benzothiadiazole-4,7-diyl[4,4- bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b']dithiophene-2,6-diyl]]: [6, 6]-phenyl C61- butyric acid methylester (PCPDTBT: PCBM) are used as active layer materials. Analysis of Microelectronic and Photonic Structures One Dimension (AMPS-1D) is a computer simulation tool for solar cell device characteristics. The first part of this study focuses on the performance and comparison of current-voltage (I-V) simulations of indium oxide (In2O3) and tin oxide (SnO2) …


Fmri Assessment Of Ischemic Stroke In Humans, Rui Yuan May 2012

Fmri Assessment Of Ischemic Stroke In Humans, Rui Yuan

Theses

Cerebral ischemia, or brain ischemia is a kind of stroke where the blood flow is insufficient to the metabolic demand of brain. The lack of oxygen supply will directly lead to the death of brain tissue. There are two major injury regions: the infarct and penumbra. Mostly, since the infarct regions became dead tissues rapidly after stroke, there is a tiny possibility to rescue them in time. But penumbra parts are different. Tissues there will be viable for hours after ischemia. Hence, both theoretically and practically, it is possible to salvage those cells in the penumbra region. Diffusion weighted image …


Three-Dimensional Magnetic Field Sensor In Ibm 0.18Μm Cmos Technology, Gang Wang May 2012

Three-Dimensional Magnetic Field Sensor In Ibm 0.18Μm Cmos Technology, Gang Wang

Theses

This work presents a compact three-dimensional Magnetic Field Sensor (MFS) designed in standard Complementary Metal-Oxide-Semiconductor (CMOS) technology. A circular Vertical Hall Device (VHD) for horizontal magnetic field detection and a split- drain Horizontal Hall Device (HHD) for the vertical magnetic field detection are integrated to implement the three-dimensional M FS. This merged design has the advantage of smaller area and lower power consumption. The sensitivity of the vertical hall device (ring-shaped magneto-resistor) and the horizontal hall device (Split-Drain Magnetic Field-Effect Transistor (SD-MAGFET)) is estimated as 0.11V/T and 2.88V/T respectively. The vertical direction of the magnetic field detection demonstrates a higher …


Microencapsulation Of The Non-Steroidal Anti-Inflammatory Drugs Into Biodegradable Polymers Using Supercritical Fluid Technology, Safaa Mohamad Al Mahdi Ali Yousif May 2012

Microencapsulation Of The Non-Steroidal Anti-Inflammatory Drugs Into Biodegradable Polymers Using Supercritical Fluid Technology, Safaa Mohamad Al Mahdi Ali Yousif

Theses

Osteoarthritis is a disease that attacks human bones especially in older people and usually nonsteroidal anti-inflammatory drugs (NSAIDS) are being prescribed for patients with Osteoarthritis. These kinds of drugs usually have low aqueous solubility and in order to have their therapeutic effects, their solubility should be enhanced. The purpose of this study was to find solution for this problem and one way to do that is to reduce the particle size by forming micro particles. In this project, one of these types of drugs ibuprofen (isobutyl-propanoicphenolic Acid) was encapsulated into a polymer (PVP polyvinylpyrrolidone) using supercritical fluid technology (Supercritical CO …