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Optimization of Electric Vehicles Wireless Charging
No full textA Master of Science thesis in Mechatronics Engineering by Abdalla Gesrou entitled, “Optimization of Electric Vehicles Wireless Charging”, submitted in December 2019. Thesis advisor is Dr. Ahmed Osman and thesis co-advisor is Dr. Shayok Mukhopadhyay. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).The growth of cars purchasing power, typically gasoline cars, has been a serious contributor to greenhouse effect. Fuel usage reduction through transportation electrification is currently among the most vital research topics. Nevertheless, electric vehicle (EV) high prices and driving distance limitations, have been causing significant roadblocks to the EVs market evolution. Reducing the number of batteries in the EV would lead to lowering the EV’s price, and decreasing the car’s weight, which would increase the driving distance to charging time ratio. To make this feasible, EVs public chargers have to be widely available. This would enable users to charge their cars frequently, increasing the available driving distance. Wireless charging can be used to eliminate any risks of contact wearing or sparks during plugging/unplugging the wired charger. Wireless charging can be achieved through a transmitter embedded below the EV’s parking slot, and a receiver fixed at the bottom of the EV. This thesis focuses on optimizing wireless charging through optimizing the coils geometry, and simulating the wireless power transfer process. Optimization was done using MATLAB optimization toolbox, and was double checked through mathematical derivation. A trend was obtained through the optimization process, which indicated that equal coils diameters results in maximum power transfer. The coils were designed on ANSYS Maxwell, with nine case scenarios having different geometrical values and change in radius, and their electromagnetic behavior was simulated. The full system, including the coils and the components of the electric circuit, was simulated at resonance frequency of 100 kHz, with the aid of ANSYS Simplorer. The amount of material used in the coils was calculated, as it affects the coils’ prices. The coils weights were also calculated, as they affect the EV’s consumed power. The introduced variable change in radius resulted in a 37% decrease in the coils weights to reach 26.5 kg, and a 37% decrease in the amount of material needed to manufacture the coils, to reach 2964 cm3. The variable change in radius slightly increased the amount of power transferred by 0.75%, to reach 17.54 kW at perfect alignment between the coils, and 9 cm separation distance.College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR
Can the Full Spectrum Fitting Technique correctly detect Age Spreads in Young Star Clusters?
No full textIntegrated spectra of star clusters have proven to be accurate tools for obtaining age, metallicity and reddening of extragalactic clusters for which resolved data is not available. In this work we investigate the possibility of recovering age spreads of young star clusters (in the range log (age/year) 6.8 to 7.2) using full-spectrum fitting approach and provide the preliminary results using model spectral combinations, in order to examine whether this approach can be used for identifying age-spreads for a grid with combinations of S/N, cluster age and population mass fraction. Our preliminary results show that false age spreads might be obtained when fitting multiple ages using integrated spectra specially for the lower S/N. A more accurate experiment to determine how reliable is the recovery of the input parameters is needed
Application of Quasi-Phase Matching Concept for Enhancement of High-Order Harmonics of Ultrashort Laser Pulses in Plasmas
No full textNovel methods of coherent short-wavelength sources generation require thorough analysis for their further amendments and practical implementations. In this work, we report on the quasi-phase matching (QPM) of high-order harmonics generation during the propagation of single and two-color femtosecond pulses through multi-jet plasmas, which allows the enhancement of groups of harmonics in different ranges of extreme ultraviolet. The role of the number of coherent zones; sizes of plasma jets and the distance between them; plasma formation conditions, and the characteristics of the fundamental radiation on the harmonic effciency at quasi-phase matching (QPM) conditions are analyzed. We demonstrate the ~40X enhancement factor of the maximally-enhanced harmonic with respect to the one generated at ordinary conditions in the imperforated plasma
Path Independence of Exotic Options and Convergence of Binomial Approximations
No full textThe analysis of the convergence of tree methods for pricing barrier and lookback options has been the subject of numerous publications aiming at describing, quantifying, and improving the slow and oscillatory convergence in such methods. For barrier and lookback options, we find path-independent options whose price is exactly that of the original path-dependent option. The usual binomial models converge at a speed of order 1∕√ to the Black-Scholes price. Our new path-independent approach yields convergence of order 1∕. Furthermore, we derive a closed form formula for the coefficient of 1∕ in the expansion of the error of our path-independent pricing when the underlying is approximated by the Cox, Ross, and Rubinstein (CRR) model. Using this we obtain a corrected model with a convergence of order ⁻³/² to the price of barrier and lookback options in the Black-Scholes model. Our results are supported and illustrated by numerical examples
Numerical Analysis of Film Cooling Shield Formed by Confined Jet Discharging on a Flat Plate
No full textThe effects of centrifugal force and thermal conductivity on the effectiveness of a film cooling shield are investigated in this study. A confined jet with 90 degree angle is used, to inject cooling fluid into hot steam, to form a film cooling shield that protect a flat plate. Film cooling is modelled in 2D using ANSYS Fluent commercial computation fluid dynamic tool. The RNG k-ε turbulence model with enhanced wall function (EWF) is selected to capture the low-Reynolds number effects near the wall. The selected turbulence model has showed better prediction of the adiabatic film cooling effectiveness accuracy (AFCE) compared to other turbulence models. The results show that centrifugal force alters the flow field and affects the film cooling shield attachment to the flat plate. A clear drop in the AFCE is observed when positive centrifugal force acts perpendicular on the confined jet, which causes overheating in the vicinity of the jet. The effect of wall thermal conductivity on film cooling effectiveness FCE is reported using different thermal conductivity ratios between wall and fluid; mainly, 1, 10, 100, 1,000 and 10,000. The results show that thermal conductivity ratios less than 1 have almost no effect on FCE while high thermal conductivity ratios deteriorate the FCE in the vicinity of the jet
Energy diplomacy in a time of energy transition
No full textThe global energy system is undergoing a transition away from a nearly complete dependence on fossil fuels toward a greater reliance on clean and renewable energy sources. Because this low-carbon energy transition will fundamentally alter the relationship between energy producers and consumers, its geopolitical ramifications are now a key concern of global energy leaders. Among the foreign policy tools that can be leveraged to support a country in managing the geopolitical consequences of an energy transition, diplomacy is one of the most important. This paper provides an analysis of how bilateral energy diplomacy can support the interests of Gulf Cooperation Council (GCC) countries during a low-carbon energy transition. The strategic objectives of bilateral energy diplomacy for GCC countries are assessed and then considered more specifically via a case study of the United Arab Emirates (UAE). The UAE case study yields foreign policy conclusions and recommendations that are intended to serve as strategic guidance for all hydrocarbon-exporting countries. The results demonstrate the strategic importance of fostering bilateral energy diplomacy with countries that can provide security of domestic energy supply, markets for the long-term monetization of hydrocarbon resources and support for economic diversification. These strategic relations have energy at the core but should extend to joint investment and science and technology collaboration in order to have maximum value.Emirates Diplomacy Academ
4D Printed Auxetic Structures with Tunable Mechanical Properties
No full textA Master of Science thesis in Mechanical Engineering by Mohammad Hani Yousuf entitled, “4D Printed Auxetic Structures with Tunable Mechanical Properties”, submitted in June 2019. Thesis advisor is Dr. Wael Abuzaid. Soft and hard copy available.Additive manufacturing (i.e., 3D printing) has revolutionized the entire design cycle from prototyping, machining, and assembly. The majority of the materials suitable for 3D printing result in rather rigid structures with a fixed set of properties. Four-dimensional printing (4D printing) addresses this limitation through the use of active and smart materials during 3D printing. The careful selection of structural design and suitable stimulus-activated smart material enables a unique set of shapes and properties to be programmed and achieved. This deviation from rigid structures with a fixed set of properties enables novel and unique applications in robotics, deployable structures, biomedical, and aerospace industries. The current work is focused on an interesting class of structures, 2D auxetic cellular solids, which exhibit distinctive mechanical properties (e.g., negative Poisson’s ratio) due to their carefully designed porous structure. 4D printing of such structures using smart materials allows for changes in the unit cell shape and dimensions to be made and thus resulting in tunable structural stiffness, Poisson’s ratio, and rigidity. This work aims to experimentally investigate the tunability of stiffness and Poisson’s ratio in 4D printed auxetic structure through utilization of programming and shape recovery properties found in Shape-Memory Polymers (SMP). Auxetic honeycomb structures with tunable mechanical properties were successfully manufactured and evaluated in this work. The attained structural stiffness was tuned in the range of 0.179-0.242 kN/mm while the Poisson’s ration was controlled from -0.33 up to even positive magnitudes of +0.69. This wide range of elastic properties was obtained from a single structure programmed to different deformation levels. Experimental evaluation of 4D printed SMP structures under constant cyclic programming/recovery conditions induced residual strains which consequently affected the mechanical properties by degrading the Poisson’s and structural stiffness. The magnitude of induced residual strains depend on the level of applied deformation during programing and the number of applied programing/recovery cycles. At the local level, full-field measurements revealed the localization of strains within the complex heterogeneous structure of the axially loaded auxetic honeycomb samples.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Space Elevators: Orbital Ring System
No full textA poster submitted in ENG 207 taught by Dr. Philip McCarthy for the Spring 2019 semester.The main purpose of a space elevator is to carry payloads into space as an alternative to conventional rockets. The following poster showcases the feasible version of the Space Elevator: The Orbital Ring System
Liposomes in Active, Passive and Acoustically-Triggered Drug Delivery
No full textCancer has become one of the most deadly noncommunicable diseases globally. Several modalities used to treat cancer patients exist today yet many have failed to prove high efficacy with low side effects. The most common example of such modalities is the use of chemotherapeutic drugs to treat cancerous cells and deter their uncontrolled proliferation. In addition to the destruction of cancerous tissues, chemotherapy destroys healthy tissues as it lacks the specificity to annihilate cancerous cells only and preferentially, which result in adverse side effects including nausea, hair fall and myocardial infarction. To prevent the side effects of non-selective chemotherapy, cancer therapy research has been focused on the implementation of nanocarrier systems that act as vehicles to encapsulate drugs and selectively transport their agent to the tumor site. In this paper, we shed light on liposomes along with three anticancer drug delivery approaches: passive, active and ultrasound-triggered drug delivery
Lipsome-coated metal organic frameworks as a new drug nanocarrier
No full textA Master of Science thesis in Biomedical Engineering by Omnia A. Mohamed entitled, “Lipsome-coated metal organic frameworks as a new drug nanocarrier”, submitted in December 2019. Thesis advisor is Dr. Rana Sabouni and thesis co-advisor is Dr. Ghaleb Husseini. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).Cancer has emerged to become one of the predominant diseases ever known to humanity, with chemotherapeutic agents as leading methods for treating it. However, this blind-sighted treatment method that targets all cells; healthy and cancerous, has led to a broad spectrum of side effects that include fatigue, hair loss, nausea and even heart problems. Although potential drug nanocarriers are currently used in the market, e.g., liposomes, yet, their drug loading capacity is still a challenging aspect limiting their usage. This work aims to investigate the development of a novel hybrid nanocarrier from liposomes and Metal-Organic Frameworks (MOFs). In this work, a successful coating of MOFs with liposomes was established by fusion during the preparation of the liposomes. The liposomal coating was verified using several techniques namely, Dynamic Light Scattering (DLS), Cryogenic transmission electron microscopy (Cryo- TEM) and zeta potential. DLS measurements showed a change in the diameter of liposomes from 150±0.82 nm to 163.1±2.16 nm for coated MOFs. Cryo -TEM also showed an increase in the diameter from 155.55 nm for Fe-BTC MOFs and 169.23 nm for coated MOFs. The zeta potential showed charge difference of unloaded, loaded and coated MOFs from a high negative value of -39.33±0.42 mv for loaded MOFs to a relatively neutral charge of 6.23±0.47 mv for coated MOFs. Low-frequency ultrasound (US) at 35 kHz was used as a stimulus to trigger drug release from coated and uncoated MOFs. The ultrasound triggered release reached up to 70% and 50% for coated and uncoated MOFs, respectively. Furthermore, comparing release profiles with and without US, showed statistically significant difference indicating that US can drastically increase the drug release. The effect of US on MOFs structure in terms of crystallinity and composition was analyzed via Fourier Transform Infrared (FTIR) and X-ray powder diffraction (XRD). The FTIR patterns showed a significant change in some of the pore bonds, thus indicating that US alters some pores in the MOFs. The XRD patterns showed that the ultrasound maintained the crystallinity of the MOFs. Further modelling of the release kinetics with ultrasound for both coated and uncoated MOFs was conducted.College of EngineeringMultidisciplinary ProgramsMaster of Science in Biomedical Engineering (MSBME