Engineering Commons^™

Window Thermal Performance Optimization In The Government Built Emirati Family House-Abu Dhabi Emirate., Tareq I.A Abuimara

Theses

Presently, the United Arab Emirates (UAE) has one of the world’s largest energy consumption per capita, with the building sector accounting for 70% of the consumed energy, primarily used for cooling. In the last three decades, the UAE government launched several housing programs that fit the needs of Emirati beneficiaries while recently targeting also energy efficiency.

This study aims at optimizing the window thermal performance in relation to orientation in a typical house within a representative governmental housing program. Often enough, housing orientation is governed by urban planning layout, where windows rarely show any adapted heat control treatment in relation …

Biodegradation Of Cresols Using Pseudomonas Putida Immobilized In Poly Vinyl Alcohol (Pva) Gel, Riham Mohamed Sorkatti Abu Bakr

Theses

The characteristics and viability of polyvinyl alcohol (PVA) as a support material for biomass immobilization and utilization for the biodegradation of cresols have been evaluated. PVA gel pellets were prepared by repeated freezing-thawing method using different PVA compositions. The porous structures of the PVA pellets were examined using a Compound Microscope and SEM and revealed that the matrix structure and pore size distribution were affected by PVA composition. Mechanical properties of the PVA gel were also characterized to evaluate the PVA integrity as a matrix for immobilizing microbial cells and found to be dependent on the PVA mass composition. The …

Physicochemical Characterization Of Safranal-Β-Cyclodextrin Inclusion Complexes Prepared By Supercritical Carbon Dioxide And Conventional Methods., Sanaz Abbaszadegan

Theses

Saffron (Crocus sativus. Linn) has attracted much attention over the last decade because it has a large number of potent and biologically active compounds such as crocin, crocetin, picrocrocin and safranal. Researchers have shown that safranal has high antioxidant and cytotoxicity activities against several types of tumour cells (e.g., hepatocellular carcinoma) both in-vitro and in-vivo. However, the low aqueous solubility of safranal prevents using it as a therapeutic or preventive agent.

β-cyclodextrin (β-CD) inclusion complexes are being used in pharmaceutical applications to alter physicochemical properties (e.g., solubility, volatility, stability, chemical reactivity, and bio-availability) of poorly water soluble drugs. Thus the …

Reliability-Performance Trade-Offs In Photonic Noc Architectures, Pradheep Khanna Kaliraj

Theses

Advancements in the field of chip fabrication has facilitated in integrating more number of transistors in a given area which lead to the era of multi-core processors. Interconnect became the bottleneck for the multi-core processors as the number of cores in a chip increased. The traditional bus based architectures, which are currently used in the processors, cannot scale up to support the increasing number of cores in a multi-core chip. Hence, Network-on-Chip (NoC) is the preferred communication backbone for modern multicore chips. However, the multi-hop data transmission using wireline interconnects result in high energy dissipation and latency. Hence, many alternative …

Comprehensive Mapping And Benchmarking Of Esaki Diode Performance, David John Pawlik

Theses

The tunneling-FET (TFET) has been identified as a prospective MOSFET replacement technology with the potential to extend geometric and electrostatic scaling of digital integrated circuits. However, experimental demonstrations of the TFET have yet to reliably achieve drive currents necessary to power large scale integrated circuits. Consequentially, much effort has gone into optimizing the band-to-band tunneling (BTBT) efficiency of the TFET. In this work, the Esaki tunnel diode (ETD) is used as a short loop element to map and optimize BTBT performance for a large design space. The experimental results and tools developed for this work may be used to (1) …

Construction Of Multi-Mode Fiber Modes Using Phase Masks, Alexandre Tulikumwenayo

Theses

Transverse fiber modes are the distribution of electromagnetic fields in the cross-section of an optical fiber through which light propagates in the fiber. Research is being conducted to explore the usage of fiber modes with the purpose of increasing the capacity and reach of optical fibers. Mode Division Multiplexing, an area in which reseach is being conducted with the same purpose, is a multiplexing scheme used in optical networks that maps data channels onto different modes, and multiplexes these modes into one fiber for transmission. This thesis focuses on the study of modes in multi-mode fibers, and the simulation of …

Analysis Of Connecting Rod Bearing Design Trends Using A Mode-Based Elastohydrodynamic Lubrication Model, Travis M. Blais

Theses

Available design trends for big end connecting rod bearings utilize widely adopted rapid methods for prediction of minimum film thickness due to their superior speed and ease of use. However, they impose unrealistic assumptions such as surface rigidity, which could compromise the accuracy of results. The significance of structural elasticity and updated models was investigated using a mode based elastohydrodynamic lubrication model which includes body forces, mass conserving cavitation, and surface roughness. Eight physical connecting rods were modeled using finite element methods and simulated over a variety of conditions, varying engine speed, bearing clearance, and oil viscosity. The results show …

Segmentation And Model Generation For Large-Scale Cyber Attacks, Steven E. Strapp

Theses

Raw Cyber attack traffic can present more questions than answers to security analysts. Especially with large-scale observables it is difficult to identify which packets are relevant and what attack behaviors are present. Many existing works in Host or Flow Clustering attempt to group similar behaviors to expedite analysis; these works often phrase the problem directly as offline unsupervised machine learning. This work proposes online processing to simultaneously model coordinating actors and segment traffic that is relevant to a target of interest, all while it is being received. The goal is not just to aggregate similar attack behaviors, but to provide …

Optical And Mechanical Investigation Of Inas /Gaas Quantum Dots Solar Cells And Inas Nanowires For The Application Of Photovoltaic Device, Yushuai Dai

Theses

Self-assembled quantum dots (QDs) and nanowires (NWs) are currently the subjects of extensive study due to their promising applications in optoelectronic devices. In order to enhance understanding of the short circuit current improvement in InAs/GaAs quantum dots solar cell (QDSC), the mechanisms of carrier escape by thermal activation and tunneling from InAs quantum dots (QDs) confinements in InAs/GaAs QDSCs are investigated. The fitted activation energy of electrons from temperature dependent photoluminescence (TDPL) is 114 meV. Using this fitted activation energy, calculated thermal escape time and tunneling time of electrons from the ground state of the QDs are 10-12 seconds and …

Performance Of Reinforced Concrete Beams Strengthened With Mechanically-Fastened Composite System Under Corrosive Environment, Amna Zaid Suwaid Al Nassibi

Theses

This study examines the effects of corrosion exposure on the flexural response of reinforced concrete (RC) beams strengthened with a powder-actuated fastened (PAF) composite system. Twenty-one RC beams were constructed and tested to failure under four-point bending. The corroded beams were subjected to 30, 60, and 100 days of accelerated corrosion that corresponded to measure tensile steel mass losses of 6, 11 and 18% respectively. Other test parameters included width of fiber reinforced polymer (FRP) composite strip, fastener length, and number of fasteners rows.

For the non-corroded beams, the PAF-FRP system resulted in up to 24% increase in beam flexural …

A Data Link Layer Protocol For Hybrid Vehicular Sensor Networks Using Practical Mobility Models With Real Maps, Sarah Madi

Theses

Safety applications in Hybrid Vehicular Sensor Networks (HVSN) require robust transmission of messages in order to deliver safety to roads and drivers as intended. Since moving vehicles are equipped with wireless sensors that utilize and share the unreliable wireless channel for communication, the transmission of safety messages must be coordinated to minimize or completely eliminate collision of exchanged packets. The first step on the way of achieving that is through the Media Access Control (MAC) layer which is responsible for managing the access to the shared media safely and without collisions.

This thesis aims at designing and implementing a HVSN …

Conductive Polymer Blends And Their Use In Memory Devices, Mohammad Yousef Al-Haik

Theses

The aim of this project is to synthesize and characterize conductive polymers made out of blending nonconductive polymers with ionic liquids. An application to demonstrate the use of these novel conductive polymers is to create an organic memory device.

Attempts to synthesize conductive polymers have been reported in the literature; several of these approaches include doping a polymer with arsenic or iodine based dopant. In this work, ionic liquids, known as plasticizer, are sued as the dopant for non-conductive polymers. There are several advantages of employing the ionic liquids over other dopants, including the maintenance of organic based blends (both …

Enzymatic Production Of Biodiesel From Fats Extracted From Lamb Meat Using Supercritical Co2, Hanifa Easa Taher

Theses

Due to the reduction in fossil fuel reserves and associated environmental impacts from using petroleum fuels, biodiesel has been presented as a feasible alternative because it is sustainable and environmentally friendly. In this study, it is proposed to investigate the feasibility of enzymatic production of biodiesel from waste animal fats using supercritical fluid technology for the extraction and reaction. The operating conditions that resulted in the optimum extraction and biodiesel production yield were identified. To the best of my knowledge of the investigators, the waste animal fat extracted by supercritical CO₂ (SC-CO₂) for the production of biodiesel …

Fpga Hardware Accelerators - Case Study On Design Methodologies And Trade-Offs, Matthew V. Ryan

Theses

Previous research has shown that the performance of any computation is directly related to the architecture on which it is performed. As a result, the performance of compute intensive applications can be improved using heterogeneous systems. These systems consist of various processor architectures such as CPU, FPGA, DSP, and GPU. Individual computations can be performed in parallel on different processor architecrues within the heterogeneous system. Computations are performed by utilizing existing designs from implementation libraries. There is a lack of FPGA accelerators for use in these libraries and as such additional implementations need to be designed.

Different design methodologies for …

Measurement Of Gas Flow Through Porous Structures Using Thz Spectroscopy, Yihui Wang

Theses

Comparing THz transmission through a sample with the transmission through free-space allows one to calculate the THz absorbance of a sample. Previous studies have focused on using THz absorbance to measure the diffusion of liquid through materials. In this study, the ability of THz spectroscopy to measure the flow of gas in a porous material, packaging foam, is investigated. Specifically, Terahertz spectroscopy from 0.5 to 0.7 THz is used to measure the THz absorption of 1, 1 -difluoroethane. Several experiments are performed to test the ability of THz spectroscopy to measure the flow of gas in a porous material: (1) …

Finite Element Modeling Of Temperature Elevation Due To Nir Exposure In Neural Tissue, Atabek Can Yucel

Theses

Near infrared (NIR) lasers have been used in various types of medical applications. Heating is one of the most important concerns in the neural tissue when illuminated with NIR light. Rodent models are frequently used to study laser-tissue interactions. As a part of ongoing research project in the neural interface laboratory, direct measurements of temperature in the rat brain cortex as a response to a pulsed sequence of NIR laser beam are available. In this thesis, finite element modeling approach is used to model and simulate the temperature elevation in neural tissue under the effect of NIR laser pulsing. Steady …

Effect Of Scan Time On Resting State Parameters, Dhruti Patel

Theses

In the past decade the interest in studying the spontaneous low-frequency fluctuations (LFF) in a resting-state brain has steadily grown. By measuring LFF (< 0.08 Hz) in blood-oxygen-level-dependent (BOLD) signals, resting-state functional magnetic resonance imaging (rs-fMRI) has proven to be a powerful tool in exploring brain network connectivity and functionality. Rs-fMRI data can be used to organize the brain into resting state networks (RSNs). In this thesis, rs-fMRI data are used to determine the minimum data acquisition time necessary to detect local intrinsic brain activity as a function of both the amplitude of low frequency fluctuations (ALFF) and the fractional amplitude of low frequency fluctuations (fALFF) in BOLD signals in healthy subjects. The data are obtained from 22 healthy subjects to use as a baseline for future rs-fMRI analysis. Voxel-wise analysis is performed on the whole brain, gray matter volume, and two previously established RSNs: the default mode network (DMN) and the visual system network, for all the subjects in this study.

Pearson’s correlation coefficients (r-values) are calculated from each subject. The entire time series for one subject is divided into 31 subsections and the r-values are calculated between each consecutive subsection in a subject. In total, there are 30 r- values. To better understand what the results mean across subjects and within subjects Fisher transformations are applied to the 30 calculated r-values for each subject to get a normal z-distribution. The mean across 22 subjects’ z-values is …

Nir Light Transmission Through Skin And Muscle, Deniz Ozgulbas

Theses

Light has been used extensively in the medical field for both therapeutic and diagnostic applications. Tissue optical window or therapeutic window defines the range of wavelengths where the light has the maximum transmittance through tissue. In this range, absorption and scattering effects are relatively lower when compared to the visible or middle infrared wavelengths. Knowledge of the transmittance through tissue can help determine the effective light intensities in medical applications.

The objective of this thesis is to determine the NIR light transmission through different thicknesses of animal tissue and its spatial spread due to the scattering effect. Primarily pork skin …

Hydrodynamic Effects Of A Cannula In A Usp Dissolution Testing Apparatus 2, Qianqian Liu

Theses

Dissolution testing is routinely used in the pharmaceutical industry to provide in vitro drug release information for drug development and quality control purposes. The USP Testing Apparatus 2 is the most common dissolution testing system for solid dosage forms. Usually, sampling cannulas are used to take samples manually from the dissolution medium. However, the inserted cannula can alter the normal fluid flow within the vessel and produce different dissolution testing results.

The hydrodynamic effects introduced by a permanently inserted cannula in a USP Dissolution Testing Apparatus 2 were evaluated by two approaches. Firstly, the dissolution tests were conducted with two …

Research On Mppt Methods For Photovoltaic System Based On Microgrid, Jingchu Ji

Theses

This thesis introduces some basic concepts about a microgrid. Then it discusses the structure of photovoltaic system (PVS) which contains a solar panel and simplified PV models. Next, it discusses and compares different methods for Maximum Power Point Tracking (MPPT) with PVS. It presents three types of DC-DC converters -- Buck, Boost and Buck-Boost converter. This work proposes to apply a DC-DC converter of Buck-Boost type to make PVS controllable because this type of converter has the largest range for operational region so that it can get the best result on MPPT. Finally, this thesis presents a kind of new …

Engineering Spores To Display G Protein-Coupled Receptors For Directed Evolution, Alyssa Misoo Kim

Theses

All human cells are surrounded by a plasma membrane made from a phospholipid bilayer, which is responsible for maintaining a biologically active species, while stopping entry of deleterious substances from the outside. G protein-coupled receptors (GPCRs) are the membrane proteins, which transmit signals across the cell membrane. GPCRs are involved in almost every physiological process, and irregular control leads to pathological conditions. Therefore, they are major drug targets. Crystal structure determination is required to understand the molecular details of activation/deactivation. However, GPCRs are difficult to crystallize because of stability issues. An efficient protein engineering system needs to be developed. The …

Study Of Poly (L-Lactic Acid)/Poly (D-Lactic Acid) Stereocomplex As Nucleating Agent For Poly (L- Lactic Acid) Crystallization, Yuan Lao

Theses

Poly (lactic acid) (PLA) is a biodegradable polymer with good renewability and processability. However, it has some drawbacks. The Poly (lactic acid) (PLA) stereocomplex formed via the interaction between optical isomers Poly (L-lactic acid) (PLLA) and Poly (D-lactic acid) (PDLA), provides improvements on PLA thermomechanical properties. To investigate the nucleating effect brought by the PLA stereocomplex, samples of PLLA blended with different content of PDLA are prepared by the solution casting method. With different cooling rates (5, 15, 25 °C/min), DSC non-isothermal crystallization experiments are performed. The results suggest that in the presence of the stereocomplex, the PLLA crystallization temperatures …

Admittance Control Of The Intelligent Assist Robot Manipulator For People With Duchenne Muscular Dystrophy, Madeline Corrigan

Theses

Duchenne muscular dystrophy (DMD), a neuromuscular disease with a prevalence of 1 in 3500 male births, results in characteristic muscle weakness which is progressive with age and leads to loss of independence. And, in this population, maintaining optimal quality of life depends on the preservation of self-sufficiency. Despite the loss of function, non-ambulant people with DMD retain some muscle strength, just not sufficient strength to overcome the force of gravity. There are a number of upper-limb passive and active orthotic devices that attempt to augment the loss of upper limb function in people with DMD by taking advantage of this …

Power Dissipation And Mixing Time In A Partially Filled Pharmaceutical Reactor Equipped With A Retreat-Blade Impeller At Different Fill Ratios, Aniruddha Banerjee

Theses

Glass-lined, stirred reactors and tanks are of significant industrial importance, especially in the pharmaceutical and fine chemical industries. These reactors are manufactured with a “glass-lining,” i.e., a glass layer applied to the agitator, the inside of the reactor/tank and to any of the surfaces in contact with its contents in order to maximize corrosion resistance, facilitate reactor cleaning, and minimize product contamination. Because of glass-lining fabrication issues, a retreat blade impeller with a low impeller clearance off the tank bottom is commonly used in glass-lined reactors. In addition, since wall baffles cannot be easily mounted on the wall of glass-lining …

Model Predictive Control For Building Temperature Regulation, Weiqiang Dong

Theses

With the rapid increase in human consumption of energy, global warming is becoming an urgent problem. According to the past research, a significant part of greenhouse gas release and electricity consumption has been connected to buildings. Heating systems are the major contributor to high energy consumption of buildings. Better methods for decreasing energy consumption of buildings should be proposed and applied.

Model predictive control is widely used in building temperature regulation. Each model predictive control has its advantage. Through the comparison of several methods, this thesis discusses their respective features. The combination of a Matlab-based modeling system CVX and model …

Production Of Stable Bcs Class Ii Drug Suspensions By Melt Emulsification And Subsequent Incorporation Into Polymer Strip Films, Emanuel Joseph Vizzotti

Theses

One of the ways to improve the dissolution rate of poorly water-soluble drugs is to produce fine drug particles with increased surface area. This increase will lead to bioavailability enhancement. However, smaller drug particles are thermodynamically unstable and tend to aggregate or grow. Therefore, proper formulation and process parameters must be chosen to keep the particles small. In this study, fine drug particles of two model drugs, fenofibrate and ibuprofen, are prepared by the melt emulsification technique. The influence of suspension formulation (i.e., the inclusion of polymers and surface-active agents) on particle stability is investigated. Moreover, different agitation techniques during …

Batch Foaming Of Hot Melt Extruded Excipient/Disintegrant/Api Pharmaceutical Formulations And The Study Of The Effects Of The Resulting Cellular Structures On Api Dissolution, Na Yao

Theses

This thesis focuses on the impact of a disintegrant included in a foamed immediate release system composed of a polymer excipient and an Active Pharmaceutical Ingredient (API). Indomethacin (INM) is used as model API; Eudragit® EPO (EPO) is used as polymer excipient; AcDiSol and Crospovidone (Cros) are used as two kinds of disintegrant. The main objectives are to gain an understanding of the resulting morphologies, as well as the impact of disintegrants on drug release from foamed polymeric matrices.

In the first part of this research, the Hot Melt Extrusion (HME) process is used to compound the following pharmaceutical formulations: …

Heterogeneous Combustion Of Condensed Particles In Transition Regime, Deniz Yildiz

Theses

A steady-state model of heterogeneous combustion for a spherical particle is developed accounting for the transition regime of heat and mass transfer. The model assumes formation of condensed products and reaction rate controlled by the transport of oxidizer to the particle surface. The model is based on the Fuchs’ limiting sphere approach. Calculations are performed for combustion of zirconium particles of different sizes. Temperature and oxygen concentration profiles are calculated and compared to those predicted by the continuous medium transfer model. It is shown that for particles in the range from 100 nm up to 30 gm heat and mass …

Effect Of Tablet Compression On The Dissolution Of Aspirin Tablets Using A Novel Off-Center Paddle Impeller (Opi) Dissolution Testing System, Chuan Sun

Theses

In the pharmaceutical industry, dissolution testing is routinely carried out to determine the dissolution rate of oral solid dosage forms. Among several testing devices, the USP Dissolution Apparatus 2 is the device most commonly used. However, despite its widespread use, this apparatus has been shown to produce test failures and to be very sensitive to a number of small geometry changes.

The objective of this study was to determine whether a novel dissolution system termed “OPI” for “off-center paddle impeller” was sensitive enough to determine differences in tablet dissolution profiles caused by different compression pressure during the tablet manufacturing process. …

Brain Computer Interface Based Neurorehabilitation Technique Using A Commercially Available Eeg Headset, Abhineet Mishra

Theses

Neurorehabilitation has recently been augmented with the use of virtual reality and rehabilitation robotics. In many systems, some known volitional control must exist in order to synchronize the user intended movement with the therapeutic virtual or robotic movement. Brain Computer Interface (BCI) aims to open up a new rehabilitation option for clinical population having no residual movement due to disease or injury to the central or peripheral nervous system. Brain activity contains a wide variety of electrical signals which can be acquired using many invasive and non-invasive acquisition techniques and holds the potential to be used as an input to …