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Design and Development of an Autonomous Caged Drone for Leak Detection in HVAC Ducts
No full textA Master of Science thesis in Mechatronics Engineering by Ahmed Khalil entitled, “Design and Development of an Autonomous Caged Drone for Leak Detection in HVAC Ducts”, submitted in October 2021. Thesis advisor is Dr. Mohammad Jaradat and thesis co-advisors are Dr. Shayok Mukhopadhyay and Dr. Mamoun Abdel-Hafez. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Interest in unmanned aerial vehicles (UAVs) has increased over the past years mainly due to the benefits that it proposes to achieve. Their ability to perform tasks accurately and efficiently in dangerous conditions makes them an optimal choice in various indoor applications. However, the problem of increased safety and precise control arises as these drones have high rotatory components. To avoid the rotary components being exposed, a cage type structure can be used which helps dampen an impact on the drone. For precise control, advanced adaptive control techniques can be used to achieve a stable vehicle path. In this thesis a hybrid rolling and flying multi-rotor drone is developed for inspection and leak detection in Heating, Ventilation, and Air Conditioning (HVAC) systems ducts through a thermal camera. A multi-rotor drone with a passive cage is designed, manufactured and controlled autonomously using Direct Model Reference Adaptive Control (DMRAC). DMRAC is coupled with a structure of PID controllers. Four methods are used and compared to overcome the drifting gain problem; dead-zone modification, sigma modification, epsilon modification and projection based modification. Additionally, more parameters are studied inside these modifications. The simulations show that all methods complete the desired route with some differences, such as gains drifting and error. The experimental multi-rotor platform is equipped with a 2D LiDAR sensor that provides a scan of the distance surrounding the multi-rotor drone in a 2D plane. An IMU sensor is used to project these distance measurements to a plane parallel to the ground along with a thermal camera for detecting leaks. The projected readings from the LiDAR is compared with the ground truth by using an Optitrack motion capture system. The platform is validated with PID and DMRAC control and the output result is compared amongst themselves, a thermal leak is detected and localized autonomously by the proposed system during real time validation.College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR
Prediction of EV Charging Behavior Using Machine Learning
No full textAs a key pillar of smart transportation in smart city applications, electric vehicles (EVs) are becoming increasingly popular for their contribution in reducing greenhouse gas emissions. One of the key challenges, however, is the strain on power grid infrastructure that comes with large-scale EV deployment. The solution to this lies in utilization of smart scheduling algorithms to manage the growing public charging demand. Using data-driven tools and machine learning algorithms to learn the EV charging behavior can improve scheduling algorithms. Researchers have focused on using historical charging data for predictions of behavior such as departure time and energy needs. However, variables such as weather, traffic, and nearby events, which have been neglected to a large extent, can perhaps add meaningful representations, and provide better predictions. Therefore, in this paper we propose the usage of historical charging data in conjunction with weather, traffic, and events data to predict EV session duration and energy consumption using popular machine learning algorithms including random forest, SVM, XGBoost and deep neural networks. The best predictive performance is achieved by an ensemble learning model, with SMAPE scores of 9.9% and 11.6% for session duration and energy consumptions, respectively, which improves upon the existing works in the literature. In both predictions, we demonstrate a significant improvement compared to previous work on the same dataset and we highlight the importance of traffic and weather information for charging behavior predictions.American University of Sharja
Long-term field performance of concrete produced with powder waste glass as partial replacement of cement
No full textThis paper reports the long-term field and laboratory-tested performance of concrete produced with 20 wt% replacement of cement with powder waste glass (WG). Field investigations of WG concrete were carried out in a large-scale field project comprising of various segments subjected to harsh weathering conditions and service load over a period of about three years. While laboratory cured WG concrete and normal concrete specimens were tested in compression and flexure at various concrete ages ranging from 3 days to 300 days. After about three years of field exposure, concrete cores were extracted from various segments of the project and tested for compressive strength, moisture sorption, and abrasion resistance. A detailed survey of the various segments of the project was carried out to physically examine the state of WG concrete after three years of service. Test results of the field WG concrete showed enhanced compressive strength, up to 57% reduction in moisture sorption and up to 61% reduction in abrasion weight loss in comparison to normal concrete at 300 days of concrete age. Similarly, the laboratory tests showed 43% gain in compressive strength and 28% gain in flexural strength of WG concrete in comparison to that of normal concrete at 90 days of concrete age. Detailed physical examination of various project segments showed no signs of deterioration or material failure after three years of service. The field project also demonstrated the constructability of WG concrete similar to that of normal concrete.MSU Physical Plant Divisio
Stabilization of Sandy Soil Against Internal Erosion Using Lime
No full textA Master of Science thesis in Civil Engineering by Shaziya Ahmed Banu entitled, “Stabilization of Sandy Soil Against Internal Erosion Using Lime”, submitted in May 2021. Thesis advisor is Dr. Mousa Attom. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Failure of hydraulic structures due to internal erosion is one of the most critical failures faced in civil engineering projects as it can destroy properties and lives. Many materials such as cement, lime, bitumen, and some chemical compounds have been used to stabilize soil. The main aim of this research is to investigate the use of lime to stabilize the sandy soil against internal erosion (or piping). To achieve the objective of this study, poorly graded and well-graded sandy soil were selected and used in this study. The initial properties of both the types of soil such as gradation, silt content, clay content, optimum moisture content (OMC) and maximum dry density were determined in accordance with ASTM standard specifications. The soils were mixed with lime at different percentages based on the dry weight of soil and were tested for different curing times (24 hours, 2 days and 7 days). Hole Erosion Test (HET) was used to evaluate the rate of erosion of lime stabilized sandy soil specimens. Soil parameters such as friction factor, coefficient of soil erosion, critical shear stress and erosion rate index were obtained from the hole erosion test and analysed. Lime was found to be more effective in stabilizing well graded sandy soil compared to poorly graded sandy soil. As application of 3% of lime by dry unit weight of soil with a curing time of 48 hours stabilized well graded soil against internal erosion to very slow type of soil erosion. While poorly graded soil required nearly double (about 5% of lime by dry unit weight of soil) with same (48 hours) curing time to get stabilized to only moderately slow type of soil erosion. Furthermore, the results proved that the increase in percentage of lime, increases the critical shear stress and the erosion rate index and hence, stabilizes the soil against internal erosion. Additionally, it was found that that addition of lime decreases the final diameter of water flow path and therefore proves soil stabilization has occurred. Moreover, the stabilized soil-lime-mixture was found to be unaffected by submersion (for up to two months) upon investigation.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Review of Communication Technologies for Electric Vehicle Charging Management and Coordination
No full textRecently, electric vehicles (EVs) have been introduced as an alternative method of transportation to help mitigate environmental issues, such as carbon emissions and fuel consumption, caused by conventional transportation systems. The implementation of effective EV charging systems is essential to motivate mass adoption of EVs. Accordingly, fast and reliable communications between the charging systems and the EVs are vital for efficient management of the charging process. Different radio access technologies (RATs) are discussed in the literature to enable communication between the highly mobile EVs and the charging subsystems, to collect and exchange information such as state of charge (SoC), users’ locations, and charging decisions between the different network entities. This information can be used to coordinate charging plans and select the optimal routes for moving vehicles. This paper presents a survey of existing literature on vehicular communications for EV charging coordination and management. The communication requirements and feasible communication technologies for vehicular communication are first discussed in details. A review of the physical layer security strategies is then presented and the role of the different RATs in EV charging coordination and management is described and studied.American University of SharjahSharjah Research Academy (SRA
A Mobile Energy Storage Unit Serving Multiple EV Charging Stations
No full textDue to the rapid increase in electric vehicles (EVs) globally, new technologies have emerged in recent years to meet the excess demand imposed on the power systems by EV charging. Among these technologies, a mobile energy storage system (MESS), which is a transportable storage system that provides various utility services, was used in this study to support several charging stations, in addition to supplying power to the grid during overload and on-peak hours. Thus, this paper proposes a new day-ahead optimal operation of a single MESS unit that serves several charging stations that share the same geographical area. The operational problem is formulated as a mixed-integer non-linear programming (MINLP), where the objective is to minimize the total operating cost of the parking lots (PLs). Two different case studies are simulated to highlight the effectiveness of the proposed system compared to the current approach.American University of Sharja
Qualitatively Examining Self-Regulation and Affect of First-Year Writing Students
No full textA Master of Arts thesis in Teaching English to Speakers of Other Languages (TESOL) by Erica Lee Payne entitled, “Qualitatively Examining Self-Regulation and Affect of First-Year Writing Students”, submitted in May 2021. Thesis advisor is Dr. Tammy Gregersen and thesis co-advisor is Dr. Rachel Buck. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Many first-year university students find it challenging to navigate a new environment while also managing limited time, additional responsibilities, and an increasingly rigorous course load. Current research seeks effective approaches for supporting these transitioning students. This qualitative Evidence-Based Practice (EBP) study adds to the conversation by examining a sample of first-year university students taking an introductory English academic writing course at an American-style university in the UAE. In the study, participants received training on a strategy involving a time-management tool known as the “Pomodoro Technique,” which was implemented with a pre-commitment device, in which students designated a plan for using the strategy over the course of four weeks as they completed their mid-term assignment for a writing course. Using the corpus of interview data gathered via focus groups and open-ended survey questions, this study explored the impact of the combination of this strategy and intervention on first year writing students’ self-regulatory abilities to monitor and control their learning, as well as their affective disposition toward tasks in their writing course. Mixed results were revealed as participants acknowledged both positive and negative responses to the strategy combination—grouped into affective and self-regulatory domains. Although respondents reported that their efficiency, time management, and focus had improved, they also described that the inherent interruptions and the irrelevance of the strategy to their ultimate grade achievement were seen as weaknesses. On an affective level, most respondents claimed to feel higher motivation, eustress that positively propelled their progress, and increased confidence in completing each task. However, a few felt somewhat frustrated by having to stop at regular intervals when they sensed they were progressing well. The study provided an easily reproducible training and intervention strategy that can be taught to first-year students, but implications suggested that its usability is limited and may need to be differentiated based on the learning styles of students and the disciplines for which the strategies are implemented.College of Arts and SciencesDepartment of EnglishMaster of Arts in Teaching English to Speakers of Other Languages (MA TESOL
The Impact of Technology on Regional Price Dispersion in the US
No full textWe analyze the behavior of inflation in the era of fast pace information thanks to technological advances, especially internet. Owing to readily available information, prices/inflation should quickly converge under perfect competition. To this end, we explore the possibility of price convergence in regional inflation in the USA including the permanency of such a phenomenon if observed, a concern for monetary policy makers. Empirically, we analyze standard deviation of regional inflation with special attention to technology. We show that standard deviation of inflation is not constant over time, but not necessarily ever-declining. Technology seems to help reduce price dispersion across regions
Potential immunomodulatory role of sesamin in combating immune dysregulation associated with COVID-19
No full textThe ongoing outbreak of novel coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused an unprecedented global health crisis. Development of a cure for this devastating disease is currently at full speed, with several vaccines against COVID-19 already authorized and administered. Currently, demand for these vaccines far exceeds supply. As such, boosting immunity represents a viable route to halt the rapid spread of SARS-CoV-2 and limit fatalities until vaccines become more readily and widely available. The use of phytochemicals appears to be a promising panacea. Sesamin, a lignan isolated from Sesamum indicum seeds, is known for its potent pharmacological properties, and is therefore hypothesized as a potential candidate in the therapeutic regimen against COVID-19. Herein, we highlight the confirmed therapeutic anti-inflammatory and immune-modulatory potential of sesamin against myriads of respiratory disorders, and tentatively suggest that sesamin may exert similar potent effects against COVID-19. Precisely, we speculate that sesamin may help alleviate COVID-19 via restoring Th1/Th2 balance and preventing inflammation and cytokine storm development. Additionally, we further support the promising role of sesamin against COVID-19 by underscoring the direct evidence, which suggests that sesamin may demonstrate promising inhibitory potential against three important SARS-CoV-2 targets, namely main protease, spike protein, and angiotensin-converting enzyme 2 receptor. Although preliminary, there is ample evidence to propose sesamin as a potential phytotherapeutic and prophylactic candidate against COVID-19. Further in vitro, in vivo, and preclinical studies are required to further substantiate the role of sesamin in the prevention and/or treatment of COVID-19
Modeling of Drug Release Kinetics from Stimuli- Responsive Micelles and Liposomes: A review
No full textNanocarriers such as micelles and liposomes were developed to enhance the delivery of therapeutic drugs to tumors. Internal or external stimuli can be applied to achieve spatiotemporal controlled release from these carriers. This will result in enhancing the therapeutic efficacy of anti-neoplastic drugs while reducing their toxicity. Mathematical modeling is used to simulate drug release from nanocarriers; this will facilitate and optimize the development and design of desirable nanocarriers in a systematic manner, rather than the existing trial-and-error approach. This review summarizes nine mathematical models often used to simulate drug release from drug delivery systems and reviews studies that employed these models to simulate drug release from conventional micelles and liposomes, as well as temperature-, pH-, and ultrasound-triggered micelles and liposomes.American University of SharjahAl-Jalila FoundationAl Qasimi FoundationPatient's Friends Committee-SharjahBiosciences and Bioengineering Research InstituteTakamul programTechnology Innovation Pioneer (TIP) Healthcare AwardsDana Gas Endowed Chair for Chemical Engineerin