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Brain Region-Based Vigilance Assessment Using Electroencephalography and Eye Tracking Data Fusion
No full textVigilance is the capacity to remain alert for an extended time while performing a task. Staying alert is obligatory in many jobs, particularly those that involve monitoring, such as surveillance tasks, security monitoring, and air traffic control. These monitoring tasks require a specific level of arousal to maintain an adequate level of cognitive efficiency. In this study, we investigate the possibility of assessing the vigilance levels using a fusion of electroencephalography (EEG) and eye tracking data. Vigilance levels were established by performing a modified version of the Stroop color word task (SCWT) for 30 minutes. Feature-level fusion based on the canonical correlation analysis (CCA) was employed to each brain region to improve the classification accuracy of vigilance level assessment. Results obtained using support vector machines (SVM) classifier show that fusion of EEG+eye tracking modalities has improved the classification accuracy compared to individual modality. The EEG+Eye tracking fusion on the right central brain region achieved the highest classification accuracy of 97.4 ±1.3%, compared to the individual Beta EEG with 92.0±7.3% and Eye tracking with 76.8±8.4%, respectively. Likewise, EEG and Eye tracking fusion on the right frontal region showed classification accuracy of 96.9 ±1.1% for both the Alpha and Beta bands. Meanwhile, when all brain regions were utilized, the highest classification accuracy of EEG+Eye tracking was 96.8 ±0.6% using Delta band compared to the EEG alone with 88.18 ±8.5% and eye tracking alone with 76.8 ±8.4 %, respectively. The overall results showed that vigilance is a brain region specific and the fusion of EEG+and Eye tracking data using CCA has significantly improved the classification accuracy of vigilance levels assessment.American University of Sharja
Treatment of Spent Caustic Using Immobilized Ionic Liquids
No full textA Master of Science thesis in Chemical Engineering by Nihal Yasir Ahmed entitled, “Treatment of Spent Caustic Using Immobilized Ionic Liquids”, submitted in April 2022. Thesis advisor is Dr. Taleb Ibrahim. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Treatment of spent caustic (SC) streams from refineries and petrochemical industries is not only complicated, but also very expensive, owing to the presence of hazardous substances, high pH levels, varying waste compositions, and the need to adhere to environmental regulations. Hydrophobic ionic liquids were investigated in a previous study for their ability to treat SC with removal efficiencies of more than 99% being achieved. However, the effective regeneration of the ionic liquids, necessary for the process to be industrially viable, was not successfully achieved. To overcome this problem, modifying the surface of nanomaterials with ionic liquids is proposed. These altered materials were utilized as adsorbents for the treatment of SC. They represent a simple, high potential, easy to regenerate, and an environmentally friendly alternative to the conventional treatment technologies. Zeolite-alginate beads loaded with trihexyltetradecylphosphonium bromide (IL) were prepared and investigated to determine its efficiency towards the treatment of SC in batch adsorption experiments. FTIR, TGA, SEM and EDX techniques were utilized to determine the physicochemical parameters of the beads. The FTIR analysis revealed that the ionic liquid was efficiently absorbed into the zeolite-alginate composite. The effect of different parameters such as pH, contact time, initial concentration and temperature on the treatment of SC by the beads, was examined. Results, demonstrated that the maximum adsorption capacity on the prepared composite occurred at pH 2, contact time of 2 hours and at 25 °C with a value of 45.88 mg/g and a removal efficiency of 93%. The pseudo-second order model explained the adsorption kinetics effectively, and the Freundlich isotherm model provided the greatest fit to the experimental data. Regeneration studies revealed that the beads could be employed for SC treatment for over four successive adsorption cycles with no significant reduction in adsorption effectiveness. The beads were also employed to investigate continuous fixed-bed adsorption of SC, as well as the effect of SC flowrate and adsorbent’s column bed height. The results were fitted to different adsorption models and it was found that the adsorption of phenol from SC streams best fit the Clark’s model.College of EngineeringDepartment of Chemical EngineeringMaster of Science in Chemical Engineering (MSChE
Toxicological impact of nanoparticles on human health: A review
No full textNanotechnology is a rapidly growing industry where nanomaterials are used in almost every field, including electronics, cosmetics, engineering, household products, biotechnology and medicine. Nanoparticles (NPs) have unique physical and chemical properties, which may cause potential hazards to human health, especially with constant exposure. Various studies have shown that NPs can enter the human body either through the respiratory tract, dermal absorption or via the gastrointestinal system and have the potential to cause respiratory disorders, behavioral changes, neurological disorders, as well as cancer. This review focuses on the health implications of NPs, specifically gold, silver, silica, titanium dioxide, aluminum, aluminum oxides, metal organic frameworks (MOF), aerosol particles, flame retardants, quantum dots, and carbon nanotubes. Herein, we discuss the routes of exposure and the impact of these nanoparticles on human health. We also summarize in-vitro and in-vivo studies that analyze the cytotoxicity profile and the associated health impact of these nanoparticles. This study could be utilized to develop well-defined guidelines for setting exposure limits for different NP types as well as a summary of related characteristics such as size, shape, morphology, and surface charge.American University of SharjahSheikh Hamdan Award for Medical SciencesFriends of Cancer Patient
Optimizing a Concentrated Solar Power Tower Plant using Artificial Neural Networks
No full textA Master of Science thesis in Engineering Systems Management by Nada Abdul Qader Omar Yahya entitled, “Anomaly Detection Based Framework for Profile Monitoring”, submitted in December 2022. Thesis advisor is Dr. Noha Hussein. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).College of EngineeringDepartment of Industrial EngineeringMaster of Science in Engineering Systems Management (MSESM
Optimization Of Smart Composite Panels For Enhanced Ballistic Performance
No full textA Doctor of Philosophy Dissertation in Engineering Systems Management by Yaqoub S. AlAhmed entitled, “Optimization Of Smart Composite Panels For Enhanced Ballistic Performance”, submitted in May 2022. Dissertation advisor is Dr. Zied Bahroun and dissertation co-advisor is Dr. Noha Mohamed Hassan Hussein. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Composite materials offer a unique combination of properties from lightweight and high strength to long-term durability and cost-effectiveness that opens the field for their application in different industries. However, under the application of an impact load, complex distribution of stresses and strains is produced in the composite. This is because the body is heterogeneous (reinforcement, matrix, and interface) with diverse mechanical properties of the phases, which may remain constant or degrade during service. Researchers investigated different impact mitigation techniques like changing core designs to enhance load impact resistance and strength. Others examined fluid-filled barriers to mitigate the impact of ballistic loading by investigating the energy response and the energy absorption. None of the research works considered investigating the optimum structure of a fluid-filled core. This research focused on designing a composite sandwich panel with an optimum fluid-filled core. A conceptual design of a recirculation capability water-filled sandwich panel core was proposed, investigated, and optimized. Numerical experiments were conducted using Abaqus/CAE software based on experimental planning. The developed model was validated using data and information drawn from the literature. Four design variables were considered: plate thickness, spacing distances between the core shapes, volume fraction of fluid in the core, and core structure shapes. Regression analyses were used to investigate the numerical model responses and develop the regression equations used in the optimization model. Later, optimization techniques were used to determine the optimum design parameters that maximize the impact resistance using GAMS software. Results show that the water’s ability to absorb kinetic energy resulted in a delay in damage initiation and propagation. Thicker plates and closer spacing between core-core structural elements increased the stiffness of the sandwich panel, improving its blast mitigation performance. Optimization results reveal that a tubular core fully filled with water offers the best combination of properties from maximizing the elastic strain energy and minimizing the external work done, the sandwich panel mass, and cost with a plate thickness of 5 mm, core-to-core spacing of 75 mm, and volume fraction of fluid of 100%. Sensitivity analysis showed that the optimum core shape selection was sensitive to all four factors.College of EngineeringDepartment of Industrial EngineeringPhD in Engineering - Engineering Systems Management (PhD-ESM
INScription: Department of International Studies (INS) Issue #9 (October 27, 2022, Issue 2)
No full textCollege of Arts and SciencesDepartment of International Studie
Effect of Vehicle-Parapet Collision Forces on Bridge Girders, Bracings, and Support Bearings
No full textA Master of Science thesis in Civil Engineering by Zeinah Mohamad Elnassar entitled, “Effect of Vehicle-Parapet Collision Forces on Bridge Girders, Bracings, and Support Bearings”, submitted in June 2022. Thesis advisor is Dr. Sami Tabsh. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).To account for the load effect due to vehicle collision with the parapet, the American Association of State Highway and Transportation Officials (AASHTO) Bridge Design Specifications contain provisions that ensure structural safety of the parapet and overhang portion of the deck slab. However, AASHTO does not consider the effect of such force on the girders, cross bracings, and supports. Lack of available literature on the subject necessitates the need to investigate the effect of this action on the structural elements that are part of the load path. In this investigation, parametric studies utilizing the finite element method on typical short and medium span composite steel girder bridges subjected to loads on the parapet are conducted. The variables that are addressed in the analysis are the length of parapet segments along the bridge, deck slab thickness, height of parapet, bridge span length, slab overhang width, number of girders, span continuity, and presence/spacing/configuration of bracings. Two types of static structural analyses are conducted, linearly elastic and nonlinear. Findings of the study showed that the bridge response obtained through 3D finite element analysis is complex in nature due to distortion induced by unsymmetrical loads and support conditions. Vertical loads due to vehicle-parapet impact forces affect the flexural stresses in the exterior girders much more than the interior girders, particularly for bridges that have few girders and are not adequately braced. The spacing of bracings and slab thickness highly impact the internal forces developed in bracing members as a result of vertical and lateral loads. The reaction components at the supports are mainly affected by the number of girders, overhang width, and span length. Structural behaviour of bridges that have adequately braced steel girders is much different than that of bridges without bracing, irrespective of the direction of the applied load on the parapet. Consideration of material nonlinearity in the analysis has little impact on the results, especially with respect to the flexural girder distribution factors and support reactions. Currently available simple approaches for analysing load effects in bridges, such as the concepts of girder distribution factor and rigid body rotation, can be useful tools for predicting bridge behaviour when subjected to load on the parapet if implemented with some modifications.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
On Weakly 1-Absorbing Primary Ideals of Commutative Rings
No full textLet R be a commutative ring with 1 ≠ 0. In this paper, we introduce the concept of weakly 1-absorbing primary ideal which is a generalization of 1-absorbing primary ideal. A proper ideal I of R is called a weakly 1-absorbing primary ideal if whenever nonunit elements a, b, c ∈ R and 0 ≠ abc ∈ I, then ab ∈ I or c ∈ √I. A number of results concerning weakly 1-absorbing primary ideals and examples of weakly 1-absorbing primary ideals are given. Furthermore, we give the correct version of a result on 1-absorbing primary ideals of commutative rings
Perceptions Governing Sustainability in the Construction Sector of the United Arab Emirates
No full textA Master of Science thesis in Construction Management by Sara Adel Abdulwahab Abdulmaksoud entitled, “Perceptions Governing Sustainability in the Construction Sector of the United Arab Emirates”, submitted in November 2022. Thesis advisor is Dr. Salwa Beheiry. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).College of EngineeringMultidisciplinary ProgramsMaster of Science in Construction Management (MSCM