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Behavior of FRP-RC Columns Using BFRP Ties under Concentric Loading
No full textA Master of Science thesis in Civil Engineering by Khaled Obeidat entitled, “Behavior of FRP-RC Columns Using BFRP Ties under Concentric Loading”, submitted in December 2019. Thesis advisor is Dr. Farid Abed. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).Several studies have investigated the use of Fiber-Reinforced Polymers (FRP) rebars in reinforced concrete (RC) flexural members. However, not enough depth of understanding is currently available with regards to their use in compression members. This research aims at investigating the structural performance of square concrete columns longitudinally-reinforced with Glass FRP (GFRP) and Basalt FRP (BFRP) bars. The use of BFRP ties as a replacement to steel transverse reinforcement in FRP and steel RC columns is also examined. A total of 20 short columns with a cross-section of 180 mm × 180 mm are cast and tested under concentric loading. The specimens included 6 BFRC RC columns, 6 GFRC RC columns and 8 steel RC columns. Half of the columns were transversely-reinforced with BFRP ties while the other similar 10 specimens were reinforced with steel ties. The parameters investigated include: (a) longitudinal reinforcement type (steel versus BFRP versus GFRP), (b) transverse reinforcement type (BFRP versus steel ties), and (c) transverse reinforcement spacing. The effects of the test parameters on the overall response of FRP RC columns including axial load capacity, failure modes, confinement efficiency (EC), ductility, strength contribution of longitudinal rebars, and deformation capacities are discussed and scrutinized. The results showed comparable performance in terms of capacity and ductility between FRP and steel RC columns and between BFRP and steel ties. The contribution of longitudinal steel reinforcement to the ultimate capacity of columns was found to be larger than the contribution of FRP rebars. However, reducing ties spacing by one-third increased the contribution of FRP bars up to 41.6% and consequently improved columns ultimate capacity and ductility. Furthermore, replacing the steel ties with BFRP ties slightly decreased the ductility and the ultimate capacity of FRP and steel RC columns. The main failure mode of all columns was compression-controlled attributed to concrete crushing at strains close to 0.003.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
A Strategic Framework for a Smart Campus: American University of Sharjah Case Study
No full textA Master of Science thesis in Engineering Systems Management by Karam Hani AbuAlnaaj entitled, “A Strategic Framework for a Smart Campus: American University of Sharjah Case Study”, submitted in November 2019. Thesis advisor is Dr. Vian Ahmed. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).As the term smart campus attracts the professionals and academics from multiple disciplines, and the technology keeps intervening in every aspect of life; it becomes inevitable for the smart campus to take place and contribute in the future vision of smart cities. As a first step to achieve this vision, it is very important to develop a clear understanding of what is a smart campus. To date, there is still no clear perception of how would a smart campus look like, or what are the main components that can form a smart campus. In this study, an intensive research is conducted to explore and compile the recent accomplishments in the fields of: smart cities, internet of things and smart campus; to utilize these recent studies into a coherent entity called ‘The Smart Campus’. The objective of this research is to propose a conceptual framework for the Smart Campus that underpins the most important criteria from the campus end users’ perception. The main criteria are defined from literature review, and a case study is conducted on the American University of Sharjah campus end users to assess the designated criteria. This exploratory research relies on both qualitative and quantitative methods to perform the analysis, taking into consideration the perceptions of students, faculties, and IT service providers. The results of the case study shows that 10 smart application scored High Importance level (H) (0.8 ≤ RII ≤ 1) based on the Relative Importance Index, and 15 other application are in the High-Medium importance level (H–M) (0.6 ≤ RI ≤ 0.8) based on the same index. Moreover, the case study shows that students prefer to deploy respectively the application of Smart Cards, Smart Classrooms, Smart Energy Management, and Smart Transportation in their campus life, and 60% of them believe that their university is capable to do the smart transformation. Nevertheless, professors and IT professionals confirmed the proposed smart criteria, and highlighted the main obstacles in: implementation cost, buildings’ reliability, and resistance to change. Finally, having defined and evaluated the criteria that underpins the smart campus framework, a set of recommendations are drawn to guide the utilization of a smart campus within higher education settings. This research opens the doors for future studies to gain a deeper insight into the type of decisions that need to be made in order to transform a traditional campus to a smart campus.College of EngineeringDepartment of Industrial EngineeringMaster of Science in Engineering Systems Management (MSESM
Teaching the world to sing - cross-cultural considerations
No full textIn 2016, I accepted a position teaching voice at the American University of Sharjah (AUS) in the United Arab Emirates (UAE). Sharjah is known as the "cultural and educational emirate," while nearby Dubai strives to be known as the "commercial, or business emirate." AUS has a higher percentage of international students than any other world-ranked institution, according to an analysis of the UK-based Times Higher Education data. Some 84% of the university's student body is made up of international students, who come from nearly 100 different countries including but not limited to India, the United States, Canada, Egypt, Jordan, Syria, Saudi Arabia, Africa, Pakistan, Southeast Asia, and the UAE. Every lesson I teach, every learning interaction in or out of the classroom, is encountered and shared through these multicultural lenses. This amazing experience has challenged me to reduce my teaching to the most universally accessible concepts I can find; consequently, I have created a way to reformulate my tried and- true-in-the-US methods to encompass the diversity of the students I now teach
On Some Applications of the Maximum Principles to a Variety of Elliptic and Parabolic Problems
No full textA Master of Science thesis in Mathematics by Sajan K. Samuel entitled, “On Some Applications of the Maximum Principles to a Variety of Elliptic and Parabolic Problems”, submitted in July 2019. Thesis advisor is Dr. Cristian Enache. Soft and hard copy available.One of the most important and useful tools used in the study of partial differential equations is the maximum principle. This principle is a natural extension to higher dimensions of an elementary fact of calculus: any function, which satisfies the inequality f′′ > 0 on an interval [a,b], achieves its maximum at one of the endpoints of the interval. In this context, we say that the solution to the differential inequality f′′ > 0 satisfies a maximum principle. In this thesis we will discuss the maximum principles for partial differential equations and their applications. More precisely, we will show how one may employ the maximum principles to obtain information about uniqueness, approximation, boundedness, convexity, symmetry or asymptotic behavior of solutions, without any explicit knowledge of the solutions themselves. The thesis will be organized in two main parts. The purpose of the first part is to briefly introduce in Chapter 1 the terminology and the main tools to be used throughout this thesis. We will start by introducing the second order linear differential operators of elliptic and parabolic type. Then, we will develop the first and second maximum principles of E. Hopf for elliptic equations, respectively the maximum principles of L. Nirenberg and A. Friedman for parabolic equations. Next, in the second part, namely in Chapter 2 and 3, we will introduce various P-functions, which are nothing else than appropriate functional combinations of the solutions and their derivatives, and derive new maximum principles for such functionals. Moreover, we will show how to employ these new maximum principles to get isoperimetric inequalities, symmetry results and convexity results in the elliptic case (Chapter 2), respectively spatial and temporal asymptotic behavior of solutions, in the parabolic case (Chapter 3).College of Arts and SciencesDepartment of Mathematics and StatisticsMaster of Science in Mathematics (MSMTH
Brain Connectivity Analysis Under Semantic Vigilance and Enhanced Mental States
No full textIn this paper, we present a method to quantify the coupling between brain regions under vigilance and enhanced mental states by utilizing partial directed coherence (PDC) and graph theory analysis (GTA). The vigilance state is induced using a modified version of stroop color-word task (SCWT) while the enhancement state is based on audio stimulation with a pure tone of 250 Hz. The audio stimulation was presented to the right and left ears simultaneously for one-hour while participants perform the SCWT. The quantification of mental states was performed by means of statistical analysis of indexes based on GTA, behavioral responses of time-on-task (TOT), and Brunel Mood Scale (BRMUS). The results show that PDC is very sensitive to vigilance decrement and shows that the brain connectivity network is significantly reduced with increasing TOT, p < 0.05. Meanwhile, during the enhanced state, the connectivity network maintains high connectivity as time passes and shows significant improvements compared to vigilance state. The audio stimulation enhances the connectivity network over the frontal and parietal regions and the right hemisphere. The increase in the connectivity network correlates with individual differences in the magnitude of the vigilance enhancement assessed by response time to stimuli. Our results provide evidence for enhancement of cognitive processing effciency with audio stimulation. The BRMUS was used to evaluate the emotional states of vigilance task before and after using the audio stimulation. BRMUS factors, such as fatigue, depression, and anger, significantly decrease in the enhancement group compared to vigilance group. On the other hand, happy and calmness factors increased with audio stimulation, p < 0.05
Battery Energy Management Techniques for Electric Vehicle Traction System
No full textA Master of Science thesis in Electrical Engineering by Ahmed Sayed AbdelAal AbdelAziz entitled, “Battery Energy Management Techniques for Electric Vehicle Traction System”, submitted in November 2019. Thesis advisor is Dr. Shayok Mukhopadhyay and thesis co-advisor is Dr. Habibur Rehman. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).Dependency of the modern society on fossil fuels has created significant levels of environmental pollution. Therefore, the automotive industry is moving towards a cleaner transportation system in the form of battery electric vehicles (BEV). A major issue with BEVs is the rapid decline in the battery runtime and lifetime represented by the State of Charge (SOC) and State of Health (SOH) respectively. Consequently, this work focuses on controlling the speed of an induction motor driven electric vehicle (EV) traction system while minimizing the SOC and SOH degradation of a Lithium-ion (Li-ion) battery bank. The first objective is designing a battery energy management (BEM) technique for an indirect field oriented (IFO) induction motor drive system using two cascaded fuzzy logic controllers (CSFLC). In this technique, the first fuzzy logic controller (FLC) generates the desired current to regulate the motor speed while the second FLC limits the current based on the battery SOC. In the second technique, a model predictive controller (MPC) regulates the motor speed while an FLC adjusts the input weight of the MPC (named FMPC), which takes the battery SOC into account when generating the current. The above mentioned controllers are implemented on an EV traction system with the New European Drive Cycle (NEDC) and the Supplemental Federal Test Procedure (US06). There is a decrease in SOC degradation of 8.1% and 5.88%, decrease in SOH degradation of 8.3% and 6.4%, and a reduction of 8.21% and 5.36% in energy consumption for the CSFLC with the NEDC and US06 drive cycles respectively. There is a decrease in SOC degradation of 4.29% and 6.57%, decrease in SOH degradation of 4.3% and 6%, and a reduction of 4.37% and 6.1% in energy consumption for the FMPC with the NEDC and US06 drive cycles respectively. The absolute average error in motor speed for the CSFLC is 3.7 RPM and 6.93 RPM as compared to the 1.28 RPM and 1.69 RPM for the FLC. While, the FMPC has 3.02 RPM and 3.13 RPM motor speed error as compared to 1.17 RPM and 1.19 RPM for the MPC with the NEDC and US06 drive cycles.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
Information disclosure in dynamic research contests
No full textWe study the design of information disclosure in a dynamic multi-agent research contest, where each agent privately searches for innovations and submits his best to compete for a winner-takes-all prize. We find that although submission is a one-time event for each agent, different disclosure policies on the agents' submissions induce different equilibrium behavior, making the design of disclosure a useful instrument for the contest sponsor. We characterize equilibrium behavior in a public contest where submissions are revealed and in a hidden contest where no submission information is revealed. In addition, for contests with indefinite duration, the public disclosure policy is an optimal policy among a natural set of disclosure policies
Analysis of an Airfoil with Rotating Cylinder for Improved Performance
No full textA Master of Science thesis in Mechanical Engineering by Anfal Al-Abdullah entitled, “Analysis of an Airfoil with Rotating Cylinder for Improved Performance”, submitted in April 2019. Thesis advisor is Dr. Mohammad Omar Hamdan and thesis co-advisor Dr. Muhammad Imran Qureshi. Soft and hard copy available.Among the multiple techniques used for boundary-layer control and flow separation delay, moving surface boundary-layer control is one of the promising approaches. Adding a rotating cylinder is one means of enhancing the aerodynamic performance of an airfoil, given that it serves to be an effective way in delaying stall. In this study, a rotating cylinder has been embedded in the leading edge of a NACA0024 airfoil. The wing model has been analyzed experimentally as well as numerically. The airfoil has been tested experimentally in a subsonic wind tunnel under different angles of attack, , and cylinder-to-freestream velocity ratios, . The effect of both parameters on the aerodynamic performance has been investigated, mainly through calculation of the lift coefficient, , the drag coefficient, , lift-to-drag ratio, /, and stall angle of attack, . Additionally, flow visualization has been carried out to get a perspective on the behavior of the rotating cylinder. Multiple photos have been captured where the streamlines of the flow are clear to the eye. A 2D numerical simulation using Computational Fluid Dynamics (CFD) has been carried out using ANSYS FLUENT 17.0 software. Through replicating the exact conditions of the experimental work, the CFD simulation has been successfully validated by its experimental counterpart. Results have shown a promising increase in the maximum lift coefficient from 0.98 at = 0 to 1.45 at = 6, which translates to around a 48% increase. The corresponding stall angle of attack has increased simultaneously from =15° at = 0, to around =35° at = 6. This increase of lift, however, is accompanied by a 47% increase in maximum drag coefficient. Furthermore, varying the cylinder exposure between 20% and 40% has shown an increase of 6.6% to 19.6% in the lift coefficient at = 10° and 20°, respectively.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Effects of Shape and Size of Cobalt Phosphate Nanoparticles against Acanthamoeba castellanii
No full textT4 genotype Acanthamoeba are opportunistic pathogens that cause two types of infections, including vision-threatening Acanthamoeba keratitis (AK) and a fatal brain infection known as granulomatous amoebic encephalitis (GAE). Due to the existence of ineffective treatments against Acanthamoeba, it has become a potential threat to all contact lens users and immunocompromised patients. Metal nanoparticles have been proven to have various antimicrobial properties against bacteria, fungi, and parasites. Previously, different types of cobalt nanoparticles showed some promise as anti-acanthamoebic agents. In this study, the objectives were to synthesize and characterize the size, morphology, and crystalline structure of cobalt phosphate nanoparticles, aswell as to determine the effects of different sizes of cobalt metal-based nanoparticles against A. castellanii. Cobalt phosphate octahydrate (CHP), Co3(PO4)2.8H2O, was synthesized by ultrasonication using a horn sonicator, then three different sizes of cobalt phosphates Co3(PO4)2 were produced through calcination of Co3(PO4)2.8H2O at 200 ˚C, 400 ˚C and 600 ˚C(CP2, CP4,CP6). These three types of cobalt phosphate nanoparticleswere characterized using a field emission scanning electronmicroscope (FESEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) analysis. Next, the synthesized nanoparticles were subjected to biological assays to investigate their amoebicidal, amoebistatic, anti-encystation, and anti-excystation effects against A. castellanii, as well as cell cytotoxicity. The overall results showed that 1.30 ± 0.70 μm of CHPmicroflakes demonstrated the best anti-acanthemoebic effects at 100 μg/mL, followed by 612.50 ± 165.94 nm large CP6 nanograins. However, amongst the three tested cobalt phosphates, Co3(PO4)2, the smaller nanoparticles had stronger antiamoebic effects against A. castellanii. During cell cytotoxicity analysis, CHP exhibited only 15% cytotoxicity against HeLa cells, whereas CP6 caused 46% (the highest) cell cytotoxicity at the highest concentration, respectively. Moreover, the composition and morphology of nanoparticles is suggested to be important in determining their anti-acathamoebic effects. However, the molecular mechanisms of cobalt phosphate nanoparticles are still unidentified. Nevertheless, the results suggested that cobalt phosphate nanoparticles hold potential for development of nanodrugs against Acanthamoeba
Electric Speedbreakers
No full textA poster submitted in ENG 207 taught by Dr. Philip McCarthy for the Spring 2019 semester.Our topic describes the utilization of mechanically modified speed breakers as alternative source for sustainable energy production. The main research question to be answered is "What are the benefits of generating power using speed breakers to meed energy demands and environmental sustainability?