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Speed Estimation Using an Inertial Measurement Unit with Convolutional Neural Networks
No full textA Master of Science thesis in Electrical Engineering by Zainab Raafat Bachir entitled, “Speed Estimation Using an Inertial Measurement Unit with Convolutional Neural Networks”, submitted in May 2019. Thesis advisor is Dr. Usman Tariq. Soft and hard copy available.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
Factors Affecting the Acoustic In Vitro Release of Calcein from PEGylated Liposomes
No full textTypical methods used in cancer treatment, including chemotherapy, are debilitating because of the various adverse side effects experienced by cancer patients. The free drug injected into the patient at given doses affects both healthy and cancerous cells. Therefore, novel methods are being researched to ensure the selectivity of the treatment. The purpose of this study is to test the release of a model fluorescent drug, calcein, from echogenic stealth liposomes, triggered by lowfrequency pulsed ultrasound. Several experimental parameters related to the ultrasound (US) and the investigated liposomes were varied in order to examine their effect on the acoustic release. Upon analysis of experimental results, the study concluded that release can be maximized by optimizing the sonication frequency, power density, and US pulse duration. When a non-isothermal chamber is used to conduct the experiments, it is important to have longer ‘Off’ than ‘On’ US periods in order to avoid overheating the liposomes. Applying such pulsation pattern can also be utilized to achieve slower release rates, which safely meet the desired drug levels at the end of the session. Our study also concluded that optimizing the liposome concentration is vital to delivering desired drug doses. Additionally, the type of lipids used in the synthesis should be carefully selected to produce stable yet acoustically sensitive liposomes capable of releasing at desired rates
Graph of Linear Transformations over a Field
No full textA Master of Science thesis in Mathematics by Yasmine Ahmed El-Ashi entitled, “Graph of Linear Transformations over a Field”, submitted in June 2019. Thesis advisor is Dr. Ayman Badawi. Soft and hard copy available.This research is an attempt to introduce a connection between graph theory and linear transformations of finite dimensional vector spaces over a field F (in our case we will be considering R). Let Rᵐ, Rⁿ be finite vector spaces over R, and let L be the set of all non-trivial linear transformations from Rᵐ to Rⁿ. An equivalence relation ~ is defined on L such that two elements f, k ϵ L are equivalent, f ~ k, if and only if ker (f) = ker (k). Let V be the set of all equivalence classes of ~. We define a new graph, G([t] : Rᵐ → Rⁿ), to be the undirected graph with vertex set equal to V , such that two vertices, [x] ; [y] ϵ G([t] : Rᵐ → Rⁿ) are adjacent if and only if ker (x) ∩ ker (y) ≠ 0. The relationship between the connectivity of the graph G([t] : Rᵐ → Rⁿ) and the values of m and n has been investigated. In addition, we determine the values of m and n for a complete and totally disconnected graph, as well as the diameter and girth of the graph if connected.College of Arts and SciencesDepartment of Mathematics and StatisticsMaster of Science in Mathematics (MSMTH
Using Lactose and Ultrasound to deliver chemotherapeuitcs
No full textA Master of Science thesis in Biomedical Engineering by Rand Hasan Abusamra entitled, “Using Lactose and Ultrasound to deliver chemotherapeutics”, submitted in May 2019. Thesis advisor is Dr. Ghaleb Husseini. Soft and hard copy available.As the number of cancer patients increase, so does the number of patients that undergo chemotherapy, as well as the suffering, caused by its side effects. To solve this adversity, an innovative form of delivering chemotherapeutics and reducing their adverse effects is envisioned through the use of nanocarriers and ultrasound. Nanocarriers; dendrimers, solid lipid nanoparticles, micelles, and liposomes can be used to exploit passive targeting and the enhanced permeability and retention (EPR) effect found in cancerous tumors. For maximum accumulation at the tumor site, active targeting, and receptor-mediated endocytosis, via the conjugation of specific ligands, including carbohydrates, small molecules, proteins, and antibodies, are utilized. The controlled release of chemotherapeutics at the tumor site is then achieved by an external or internal trigger. Hepatocellular carcinoma has been found to overexpress the Asiaglycoprotein Receptor (ASGPR). Therefore, liposomes are synthesized through the lipid film hydration method and conjugated with Lactobionic acid (LA) as a targeting moiety. Infrared spectroscopy and phenol-sulfuric acid assay confirmed the attachment and molecular structure. Dynamic Light Scattering (DLS) determined the size and dispersity of the lactosylated liposome and NH2 liposomes encapsulating calcein to be 85.7±1.2 nm and 89.2±2.7 nm, respectively. Controlled release of calcein (a model drug), is achieved through low-frequency Ultrasound (US) as an external trigger at 3 power intensities of 7.46, 9.85 and 17.31 mW/cm2. The release mechanism was studied using nine different mathematical kinetic models: zero-order, first-order, Higuchi, Hixon-Crowell, Korsmeyer-Peppas, Baker-Lonsdale, Weibull, Hopfenberg and Gompertz. The release data were found to follow the Weibull model, having the highest coefficient of determination (R2). Control liposomes followed first-order release Fickian diffusion and LA liposomes had a combined release of Fickian and case II diffusion with a b-value of 1.0 and 0.91, respectively. The results of this thesis show the utility of using targeted liposomes and ultrasound in cancer treatment.College of EngineeringMultidisciplinary ProgramsMaster of Science in Biomedical Engineering (MSBME
Stochastic Geometry-Based Model for Dynamic Allocation of Metering Equipment in Spatio-Temporal Expanding Power Grids
No full textWith smart grids replacing conventional power grids and rapidly expanding in both space and time, ensuring an acceptable system observability becomes a challenge in spatio-temporal expanding power grids. In addition, system operators face another challenge, namely, financial budget constraints. To address these challenges, a metering equipment allocation strategy for monitoring of the power grid state needs to be dynamic in both space and time. Unfortunately, existing metering allocation strategies are quite limited. They usually deal with static power grid topologies, and hence, do not reflect the spatio-temporal expansion of the power grid. In this paper, a spatio-temporal power grid model is proposed based on stochastic geometry, which we show that it is in a good match with real-world power grids. The proposed model enables us to carry out tractable dynamic allocation of metering equipment in a large (city-wide) and structurally evolving power grid. Using the developed model, a multi-year algorithm for the allocation of metering equipment is proposed based on finite horizon dynamic programming, given budgetary and technical constraints on system observability. Several case studies for metering allocation are demonstrated through simulation results.National Priorities Research Program (NPRP) from the Qatar National Research Fun
Data Embedding in HEVC Video by Modifying the Partitioning of Coding Units
No full textThis paper proposes a data embedding solution in HEVC videos by modifying the partitioning of Coding Units (CUs). The partitions of a CU are first represented as a sequence of binary flags. The flags pertaining to 16x16 sub CUs are used as a cover for data embedding, where 6 or 4 message bits are embedded per CU. The data embedding algorithm guarantees that a maximum of one partition is modified per message segment, therefore, in a given CU, either 0, 1 or 2 partitions are modified. The Proposed solution is assessed in terms of message payload, number of modified partitions, loss in video quality as indicated by the PSNR results, mean objective scores and excessive bitrate. The proposed solution can embed messages with up to an average payload of 32.6Kbit/s with a corresponding average distortion of less than 0.5dB. Comparisons with existing solutions reveal that the proposed solution maintains similar message payloads with less modifications of CU partitioning and at the same time resulting in less distortions for the cover video
Metallic coating thickness assessment over nonmagnetic metals using eddy current technology
No full textA Master of Science thesis in Mechanical Engineering by Zain Ali Ansari entitled, “Metallic coating thickness assessment over nonmagnetic metals using eddy current technology”, submitted in April 2019. Thesis advisor is Dr. Bassam Abu-Nabah and thesis co-advisor Dr. Maen Alkhader. Soft and hard copy available.Recent improvements in apparent eddy current conductivity (AECC) spectroscopy lends itself as a practical approach to assess metallic coating thicknesses over nonmagnetic metals. It can potentially offer one-order of magnitude improvement in coating thickness estimation when compared to existing phase-sensitive single-frequency and impedance-based multiple-frequency measurement systems. Existing methods require the lift-off distance between the sample and calibration blocks to be consistent to ensure that the obtained measurement is accurate. Building on AECC measurement capabilities, which offer a significantly reduced sensitivity to those deviations, a robust forward and inverse approach is developed in this thesis using single-frequency AECC measurements. The proposed inversion algorithm is developed using the Bisection method, a numerical interpolation technique used for approximating solutions where determining the exact answer is not possible. The logarithmic nature of the problem as well as the requirement of two initial guesses to start the iteration process while covering the entire coating thickness range of interest further justifies the use of the selected method. This not only reduces AECC spectroscopy measurements from a broad frequency range to single-frequency measurements, but also reduces the coil diameter by one-order of magnitude while complying with the plane-wave approximation in the lift-off range of interest. The accuracy in estimating coating thicknesses using both single- and multiple-frequency AECC measurement techniques are compared numerically and experimentally in agreement with the plane-wave approximation for different coating thicknesses relevant to the industry. It is demonstrated that AECC measurement technology delivers 3% uncertainty in metallic coating thickness estimation over nonmagnetic metals in a ±25.4 μm liftoff range. This makes it a practical approach to replace commercially available measurement systems while offering one-order of magnitude improvement in coating thickness estimation.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Selective Removal of Dual Dyes from Aqueous Solutions Using Metal Organic Framework (MIL-53(Al))
No full textA Master of Science thesis in Chemical Engineering by Miral Osama Yacoub Al Sharabati entitled, “Selective Removal of Dual Dyes from Aqueous Solutions Using Metal Organic Framework (MIL-53(Al))”, submitted in November 2019. Thesis advisor is Dr. Rana Sabouni. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).Organic dyes released from many industries such as textile, leather, and paper industries can be a threat to the environment and living creatures. Adsorption stands out as one of the favorite dye removal methods among the countless tried-and-tested techniques due to its excelling capability to remove nearly any kind of dyes. In the last two decades, there has been an ongoing research on Metal Organic Frameworks (MOFs) for the removal of dyes from wastewater owing to their extraordinary properties, high adsorption capacities, high stability and regenerability. In this thesis, the adsorption process of the cationic dye Malachite Green (MG) and the anionic dye Methyl Orange (MO) onto a MOF, namely, MIL-53(Al) was studied under several experimental parameters. Batch experiments were performed to investigate the feasibility of this MOF as possible adsorbent for the removal of MG and MO from both single and binary-dye aqueous solutions. Experimental results revealed that MIL-53(Al) can quickly bind to both types of dyes with high removal efficiency of more than 95%. The effects of different parameters such as adsorbent dosage, initial concentration of dye solution, pH of the solution, and temperature on the adsorption process were examined. Adsorption kinetic data were then fitted using pseudo first-order, pseudo second-order, elovich, and intraparticle diffusion models, showing that pseudo second-order model had the best fit for both dyes among the other models in both single and binary-dye systems with R2>0.996. Moreover, adsorption isotherm models of Langmuir and Freundlich were studied and the isotherm data was found to be in good agreement with the Freundlich isotherm for both dyes. Thermodynamics studies of change in Gibbs free energy, enthalpy, and entropy were carried out and showed that the adsorption of both dyes was endothermic and spontaneous. The selectivity test for an equimolar binary-dye solution containing both MG and MO suggested the higher affinity of MIL-53(Al) towards MO over MG, as it reached a value of 13.582 at the optimum conditions. Finally, excellent reusability of MIL-53(Al) was shown by utilizing it for 4 cycles of adsorption-desorption with almost no reduction in the adsorption capacity, bringing about additional examination of its applicability.College of EngineeringDepartment of Chemical EngineeringMaster of Science in Chemical Engineering (MSChE
Shear Strengthening of Reinforced Concrete Beams Using CFRP Wraps
No full textThe need to retrofit existing reinforced concrete (RC) structures have increased over the decades due to corrosion of steel reinforcement inside the concrete, neglect and overuse, and increased loading. Experimental and numerical studies in this research field showed that using fiber-reinforced Polymer (FRP) materials to strengthen RC members in shear, flexure, and column confinement applications is an effective method to retrofit RC structures. This strengthening technology has numerous advantages over conventional steel plating, such as providing high strength-to-weight ratio, versatility, durability, and ease of use to strengthen RC members. The purpose of this paper is to study the effect of strengthening shear deficient RC beams with externally bonded (EB) carbon fiber-reinforced polymer (CFRP) sheets with different wrapping configurations. Two shear strengthening wrapping schemes of CFRP sheets will be investigated; U-Wrapped and completely Wrapped. Although the completely wrapped scheme is more effective, however, due to its limitations, the U-Wrapped scheme became the most commonly used method in shear strengthening of RC structures. The drawback of this strengthening scheme is the premature failure caused by debonding of the CFRP laminates, without utilizing its full strength. The main aim of this study is to compare the performance of a U-Wrapped T-beam with two completely wrapped rectangular beams. The first strengthened rectangular specimen (WBR1) has a depth equivalent to the T-beam’s web height, while the second strengthened rectangular specimen (WBR2) has a depth equivalent to the T-beam’s total depth. In addition, a control T-beam and two rectangular beams were cast and tested as benchmark specimens. The experimental test results showed that the beam strengthened by U-Wrapped CFRP sheets increased the control beam’s shear strength by 114.82%, while the increase in shear capacity of the completely wrapped equivalent WBR1 and WBR2 beams over their control unstrengthened specimens was 69.28% and 201.63%, respectively. In addition, the completely wrapped scheme provided more ductility compared to that of the U-Wrapped T-beam specimen, that failed by CFRP sheets debonding in a brittle manner. Thus, it could be concluded that an ideal way to increase the shear capacity and ductility of RC beams is to completely wrap the beams using CFRP sheets. However, if the completely wrapping scheme is not possible due to geometrical obstructions, U-wrapping scheme could be effective in increasing the shear capacity of RC beams but will fail in a brittle mode by sheet debonding without utilizing its full strength. Anchoring the CFRP U-Wraps could be a viable solution to enhance the performance of strengthened RC beams that should be investigated in future research studies
Evaluation of Microplastics in Beach Sediments along the Coast of Dubai, U.A.E
No full textA Master of Science thesis in Civil Engineering by Huda Aslam entitled, “Evaluation of Microplastics in Beach Sediments along the Coast of Dubai, U.A.E”, submitted in May 2019. Thesis advisor is Dr. Tarig Ali and thesis co-advisor is Dr. Md. Mortula. Soft and hard copy available.The unprecedented increase in consumption in conjunction with poor management of plastic waste have resulted in global contamination of both terrestrial and marine environments. Plastic debris undergoes fragmentation, resulting in the formation of microplastics, a synthetic polymers less than 5 mm in size. Significant amounts of microplastics have been globally observed in beach sediments. However, no studies have addressed microplastic contamination of marine sediments and/or coastal water in the United Arab Emirates. In this study, microplastic contamination in beach sediments of sixteen beaches along the Arabian Gulf coast in Dubai have been studied. Five samples of beach sediment were collected approximately from 1 cm below the surface from each beach along a 100 m stretch using a 0.5 m by 0.5 m, steel quadrant along the wrack lines. Density separation was used to extract microplastics from the sediment samples. The number of pieces of microplastics were identified under a 40X dissecting microscope and categorized by color and shape. Furthermore, microplastics polymer types were identified through FT-IR analysis. The results showed that the average weight of microplastic is 0.33 mg. g⁻¹ of sediment (or 953 mg.m⁻²) and the number of microplastic is 59.71 items.kg⁻¹ of sediment (or 165 items.m⁻²) in the study area. A total of 3366 pieces of microplastic were found in the 80 samples with 10 different colors; blue, red, green, yellow, black, white, grey, orange, pink, and transparent. The analysis showed that blue microplastics are more abundant in terms of numbers, while white ones are most abundant in terms of the number of microplastics per square meter (items.m⁻²) and number of microplastics per kg dry weight of sediment (items.kg⁻¹). Furthermore, four shapes of microplastics were identified including fiber (most dominant), string, pieces, and polystyrene spheres. FT-IR analysis was conducted to identify the polymer type of fibers and strings that were large enough to handle using forceps which were 1396 microplastics. 63.67% of the samples were identified to be polyethylene and 32.94% were found to be polypropylene. XRF analysis identified 14 heavy metals on the extracted microplastics including Cr, Ni, Cu, Zn, and Pb, which are classified as priority pollutants by EPA.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE