AUS Repository (American University of Sharjah)
Not a member yet
2669 research outputs found
Sort by
Laplace Adomian Solutions to Fractional Differential Equations that Arise in Natural Science and Engineering Applications
No full textA Master of Science thesis in Mathematics by Fatima H. Rabah entitled, “Laplace Adomian Solutions to Fractional Differential Equations that Arise in Natural Science and Engineering Applications”, submitted in June 2022. Thesis advisor is Dr. Marwan Abukhaled and thesis co-advisor is Dr. Suheil Khoury. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).In this thesis, we investigate the numerical solution of fractional differential equations subject to initial and boundary conditions. For the solution of such equations, we use two iterative approaches. First, we apply the Laplace Decomposition Method, which is a combination of two approaches, namely the Laplace Transform and the Adomian Decomposition Methods. Then, we implement the Differential Transformation Method. Finally, we apply the above mentioned methods to real life problems such as solving complex nonlinear Enzyme Inhibitor Reactions Model and a COVID-19 Model.College of Arts and SciencesDepartment of Mathematics and StatisticsMaster of Science in Mathematics (MSMTH
A Decision Support Tool for Enhancing Social Sustainability within the UAE Construction Sector
No full textA Doctor of Philosophy Dissertation in Engineering Systems Management by Sara Saboor entitled, “A Decision Support Tool for Enhancing Social Sustainability within the UAE Construction Sector”, submitted in May 2022. Dissertation advisor is Dr. Vian Ahmed. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).College of EngineeringDepartment of Industrial EngineeringPhD in Engineering - Engineering Systems Management (PhD-ESM
Efficiency of parallel anisotropic mesh adaptation for the solution of the bidomain model in cardiac tissue
No full textElectrocardiology models are nonlinear reaction–diffusion type systems, where the numerical simulation requires extremely fine meshes to accurately compute the heart’s electrical activity. Anisotropic mesh adaptation methods have been proven to be efficient for simulating cardiac dynamic by many authors and showed a considerable improvement in the numerical accuracy while reducing the computational expenses. However, the efficiency of these techniques in parallel computing environments has not been shown yet, especially when compared to the performance of parallel uniform meshes. In this paper, we demonstrate the efficiency of a parallel anisotropic mesh adaptation method for the solution of the bidomain model in cardiac tissue. The technique is based on an efficient error estimator appropriate for second or higher order numerical solutions. To demonstrate the effectiveness of the developed methodology, comparisons between the numerical simulations on parallel adapted meshes with those on parallel uniform meshes are presented. The computational efficiency is assessed by computing spiral and scroll waves in cardiac tissue.Calcul QuébecCompute CanadaAmerican University of Sharja
Youth Resilience and Well-Being During the COVID-19 Pandemic: The Importance of Supporting Social Identity Development
No full textSlides from a presentation entitled "Youth Resilience and Well-Being During the COVID-19 Pandemic: The Importance of Supporting Social Identity Development" by Brien K. Ashdown, presented at the 50th anniversary meeting of the Society for Cross-Cultural Research, February 2022 in San Diego, California, USA
Comparative Evaluation of Membrane Filtration on the Tertiary Treatment of Synthetic Secondary Effluent
No full textWastewater reuse is essential for sustainable water management. However, it requires tertiary treatment within the plant to ensure suitable water quality. This project aims to investigate the comparative performance of conventional tertiary treatment (sand filtration) against membrane filtration technology to demonstrate the viability of membrane treatment for wastewater reuse. Sand filtration along with two membrane filtrations, Nano Filtration (NF) and Reverse Osmosis (RO), were tested for their efficiency in removing the target pollutants: chromium, phosphate, and UV-254 from secondary effluent. Standard medium-sized laboratory setups were used. Synthetic secondary effluent was used for comparison among the different treatment processes. The synthetic effluent was compared to the real wastewater to demonstrate the reliability of using synthetic effluent. Evaluation of the role of time and pressure on the treatment efficiency was also examined. Based on the experimental results, RO had the highest removal efficiency for all pollutants with more than 90% removal. The experimental results also showed that synthetic wastewater was reliable in representing the treatability of real wastewater. Time did not seem to have an impact on the quality of filtration. Moreover, as pressure increased there was a slight increase in the efficiency. This trend was observed in all pollutants except UV-254. ANOVA showed different results of the effect of pressure on the removal efficiency in both RO and NF as well as time in NF.American University of Sharja
LoRa Sub Milliwatt Transceiver Design to Reduce Space Solutions Mass
No full textA Master of Science thesis in Electrical Engineering by Hessa Ali Hussain Ahmed Ali entitled, “LoRa Sub Milliwatt Transceiver Design to Reduce Space Solutions Mass”, submitted in May 2022. Thesis advisor is Dr. Lutfi Albasha. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Space sector is a popular research area. The world is trying to launch different space solutions to improve our life. However, the price of launching any solution is extremely expensive as the price is directly proportional to the mass of the spacecraft and its subsystems. In order to have space accessible to more developers, the design of the spacecraft needs to be optimized to reduce the mass as much as possible. One of the main contributors to this high mass is the harness of the satellite which carries the data within the spacecraft. Thus, the main objective of this research is to introduce an ultra-low power consumption (sub-milli-watt) transceiver using LoRa (Long Range) technology. Specifically, focusing on designing small size transceiver to be used inside CubeSats with minimum possible power consumption that works in Industrial, Scientific and Medical (ISM) band to replace the harness. The design of this Mini Printed Circuits Board (PCB) transceiver is modular to fit any existing PCB designs in the market to be able to collect all the data using Inter-Integrated Circuit (I2C) and distribute it by small antenna using LoRa scheme. The data can be formatted in anyway then received by the mini transceiver to be processed and distributed around the different CubeSat subsystems using LoRa. The solution proposed in this research is unique as it has never been addressed in space applications before, to the best knowledge of the author.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
Development and Psychometric Evaluation of the Antibiotic Knowledge and Consumption Tool (AKCT)
No full textKnowledge of antibiotics and awareness of microbial resistance are essential for appropriate antibiotic consumption. This study aimed to develop and validate a measure of antibiotic knowledge and consumption (AKCT) and to make it available in the Arabic language and context. The tool was developed and applied on individuals ≥ 18 years, with mastery of Arabic or English. Exploratory factor analysis using principal-component analysis tested the psychometric properties of the items. AKCT scores were compared with the Infectious Numeracy Test (INT) scores to establish convergent validity. Cronbach’s α > 0.7 measured reliability. Three hundred-eighty-six participants completed the questionnaire, achieving a 95.3% response rate. Five components were retained after factor analysis: Side-effects and resistance, Access to antibiotics, Recovery after use, Antibiotics use indications, and Body response. Cronbach’s α = 0.85. The mean ± SD of AKCT = 9.82 ± 3.85 (range = 7–20); lowest scores were related to “Side-effects and resistance” (2.32 ± 2.00, max = 7) and “Antibiotic use indications” (1.61 ± 1.29, max = 5). Scores on the AKCT and INT positively correlated. The AKCT is a valuable, valid, and reliable tool developed for measurement of antibiotic knowledge and consumption behaviors to identify specific areas needing improvements; hence, targeted interventions are devised
Improved Cognitive Vigilance Assessment after Artifact Reduction with Wavelet Independent Component Analysis
No full textVigilance level assessment is of prime importance to avoid life-threatening human error. Critical working environments such as air traffic control, driving, or military surveillance require the operator to be alert the whole time. The electroencephalogram (EEG) is a very common modality that can be used in assessing vigilance. Unfortunately, EEG signals are prone to artifacts due to eye movement, muscle contraction, and electrical noise. Mitigating these artifacts is important for an accurate vigilance level assessment. Independent Component Analysis (ICA) is an effective method and has been extensively used in the suppression of EEG artifacts. However, in vigilance assessment applications, it was found to suffer from leakage of the cerebral activity into artifacts. In this work, we show that the wavelet ICA (wICA) method provides an alternative for artifact reduction, leading to improved vigilance level assessment results. We conducted an experiment in nine human subjects to induce two vigilance states, alert and vigilance decrement, while performing a Stroop Color–Word Test for approximately 45 min. We then compared the performance of the ICA and wICA preprocessing methods using five classifiers. Our classification results showed that in terms of features extraction, the wICA method outperformed the existing ICA method. In the delta, theta, and alpha bands, we obtained a mean classification accuracy of 84.66% using the ICA method, whereas the mean accuracy using the wICA methodwas 96.9%. However, no significant improvement was observed in the beta band. In addition, we compared the topographical map to show the changes in power spectral density across the brain regions for the two vigilance states. The proposed method showed that the frontal and central regions were most sensitive to vigilance decrement. However, in this application, the proposed wICA shows a marginal improvement compared to the Fast-ICA.American University of Sharja
Fluoroscopic 3D Image Generation from Patient-Specific PCA Motion Models Derived from 4D-CBCT Patient Datasets: A Feasibility Study
No full textA method for generating fluoroscopic (time-varying) volumetric images using patient-specific motion models derived from four-dimensional cone-beam CT (4D-CBCT) images was developed. 4D-CBCT images acquired immediately prior to treatment have the potential to accurately represent patient anatomy and respiration during treatment. Fluoroscopic 3D image estimation is performed in two steps: (1) deriving motion models and (2) optimization. To derive motion models, every phase in a 4D-CBCT set is registered to a reference phase chosen from the same set using deformable image registration (DIR). Principal components analysis (PCA) is used to reduce the dimensionality of the displacement vector fields (DVFs) resulting from DIR into a few vectors representing organ motion found in the DVFs. The PCA motion models are optimized iteratively by comparing a cone-beam CT (CBCT) projection to a simulated projection computed from both the motion model and a reference 4D-CBCT phase, resulting in a sequence of fluoroscopic 3D images. Patient datasets were used to evaluate the method by estimating the tumor location in the generated images compared to manually defined ground truth positions. Experimental results showed that the average tumor mean absolute error (MAE) along the superior–inferior (SI) direction and the 95th percentile in two patient datasets were 2.29 and 5.79 mm for patient 1, and 1.89 and 4.82 mm for patient 2. This study demonstrated the feasibility of deriving 4D-CBCT-based PCA motion models that have the potential to account for the 3D non-rigid patient motion and localize tumors and other patient anatomical structures on the day of treatment.American University of Sharja