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A theoretical analysis of an air stripper–biofilter system (ASBF) for industrial wastewater treatment
No full textIn this study, we focus on the industrial wastewater contaminated with volatile organic compounds (or VOC’s) which are carbon-containing compounds such as benzene, toluene, xylene, styrene, etc. VOC’s in general are toxic and potentially carcinogenic and they harm aquatic life and the environment. In this research, we focus on a theoretical analysis of VOC removal from industrial wastewater using a hybrid system that combines two processes, namely air-stripping and biofiltration (ASBF). In this system, airstream is first contacted with industrial wastewater in an air-stripping tower and depending on the air stripping efficiency clean water, which is devoid of VOCs, leaves the unit as the effluent. The contaminated air stream is then fed to a biofilter that eliminates VOCs by biological degradation. The theoretical predictions conducted through modeling demonstrate effective removal of VOCs from wastewater can be achieved in the ASBF system under current operating conditions
Assessment of Usability of Web-Based Applications' User Interfaces
No full textA Master of Science thesis in Computer Engineering by Ali Mohamed Ali Mohamed entitled, "Assessment of Usability of Web-Based Applications' User Interfaces," submitted in May 2017. Thesis advisor is Dr. Tarik Ozkul. Soft and hard copy available.System intelligence can be expressed in terms of how much it helps to make a desired task easy for human beings. The concept can be extended to user interface of computer software which is the cornerstone of human- machine interaction. User interface is the key in determining the user experience with a given system; regardless whether the system is for an industrial control system or a website. It is very much desirable to make the user interface of a software user friendly so that the user can understand and use the software as intuitively as possible. Just as the Machine Intelligence Quotient (MIQ) is used for describing "intelligence" of a system, we would like to devise a systematic scoring system to describe the quality of user interface (UI). In this work, an objective and automated method of evaluating the user interface quality is proposed and ways of comparing against existing subjective heuristic methods are explored. A derivative of Machine Intelligence Quotient (MIQ) method, called User Interface Quotient "UIQ" is used as an objective way of evaluating user interface equality.College of EngineeringDepartment of Computer Science and EngineeringMaster of Science in Computer Engineering (MSCoE
Alternating Direction Implicit Method for the Electro-Cardiology Models
No full textA Master of Science thesis in Mathematics by Zeinab Rammal entitled, "Alternating Direction Implicit Method for the Electro-Cardiology Models," submitted in May 2017. Thesis advisor is Dr. Youssef Belhamadia. Soft and hard copy available.Electrophysiology is an area of science that led to innovative experimentations between clinicians and scientists. Studying and understanding cardiac dynamics plays a key role in designing therapies, preoperative planning, and studying arrhythmias, fibrillations and other cardiac anomalies. Exploring the heart dynamics in three dimensions in vivo is difficult, and hence an alternative is needed. Mathematical modelling offers a valuable, yet computationally expensive tool for such exploration. The mathematical models of the electrical activity of the heart consist of a system of nonlinear partial differential equations coupled with a system of stiff ordinary differential equations. Numerical simulation of this coupled system requires accurate space and time discretization. In this work, an Alternating Direction Implicit Method (ADI) is presented as a new numerical scheme for solving the electrical model of the heart. Two-dimensional numerical results are presented illustrating the advantages and robustness of this proposed method. Comparison with the Crank-Nicolson Adams Bashforth (CNAB) method is demonstrated and the advantages of ADI are explained in terms of run time and memory consumption.College of Arts and SciencesDepartment of Mathematics and StatisticsMaster of Science in Mathematics (MSMTH
Smart City and Smart Tourism: A Case of Dubai
No full textOver the past decade, the advent of new technology has brought about the emergence of smart cities aiming to provide their stakeholders with technology-based solutions that are effective and efficient. Insofar as the objective of smart cities is to improve outcomes that are connected to people, systems and processes of businesses, government and other public- and private-sector entities, its main goal is to improve the quality of life of all residents. Accordingly, smart tourism has emerged over the past few years as a subset of the smart city concept, aiming to provide tourists with solutions that address specific travel related needs. Dubai is an emerging tourism destination that has implemented smart city and smart tourism platforms to engage various stakeholders. The objective of this study is to identify best practices related to Dubai’s smart city and smart tourism. In so doing, Dubai’s mission and vision along with key dimensions and pillars are identified in relation to the advancements in the literature while highlighting key resources and challenges. A Smart Tourism Dynamic Responsive System (STDRS) framework is proposed while suggesting how Dubai may able to enhance users’ involvement and their overall experience
Modeling and Control of a Thermally Driven MEMS Actuator for RF Applications
No full textA Master of Science thesis in Electrical Engineering by Shahabeddin Vamegh Estahbanati entitled, "Modeling and Control of a Thermally Driven MEMS Actuator for RF Applications," submitted in May 2017. Thesis advisor is Dr. Rached Dhaouadi and thesis co-advisor is Dr. Maher Bakri-Kassem. Soft and hard copy available.Thermally driven V-shaped microelectromechanical systems (MEMS) actuators have been used extensively in different fields of MEMS including RF MEMS applications. For this reason, developing a dynamic model is of importance for understanding the MEMS actuator dynamic behavior and for improving its transient response. Obtaining such a model is challenging as multi-physics phenomena are involved in the actuation mechanism. The complexities involved in modeling can be reduced by using macromodeling approaches. As such, a new mixed-level nonlinear electro-thermo-mechanical dynamic macromodel for a thermally driven V-shaped MEMS actuator is proposed. The proposed reduced-order macromodel is composed of a nonlinear circuit-level electrothermal macromodel and a nonlinear system-level thermo-mechanical macromodel obtained by the application of the Galerkin method. The system dynamic behavior is successfully reproduced using the proposed macromodel. The results obtained by the macromodels are in good agreement with the finite element ANSYS simulations and are computationally less expensive by far. Furthermore, the experimental static tip displacements of the actuator for different actuation voltages are in very good agreement with steady-state values of the actuator's tip displacements obtained by the proposed macromodel, and the maximum error obtained is less than 9%. Furthermore, a first-order dynamic model, based on the ANSYS input voltage and output displacement data, is developed in order to describe the displacement transient response of the MEMS actuator. The results obtained from the first-order and the ANSYS models are in very good agreement. The electro-thermo-mechanical macromodel and the first-order model are then used in closed-loop form with conventional and adaptive proportional-integralderivative (PID) algorithms to speed up the displacement transient response of the thermal MEMS actuator. Using SIMULINK, it is shown that the adaptive PID controller outperforms the conventional PID controller by meeting all the design requirements.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
Cortical EEG Source Localization of Focal Epilepsy
No full textA Master of Science thesis in Electrical Engineering by Wisal Elfatih Mohamed Siyam entitled, “Cortical EEG Source Localization of Focal Epilepsy”, submitted in November 2017. Thesis advisor is Dr. Hasan Mir and thesis co-advisor is Dr. Hasan Al-Nashash. Soft and hard copy available.Brain source localization allows us to localize different brain regions that are activated during neural activity. Several imaging modalities can be used for recording neural activity and are essential in clinical applications. One of these clinical applications is epilepsy diagnosis and localization. Structural or/and functional imaging techniques are used for patients to investigate epilepsy, classify seizures, and in pre-surgical evaluation. This report summarizes the most common imaging techniques for epilepsy diagnosis. It will then make use of electroencephalography (EEG) readings to localize epileptogenic regions in the brain, as it is a noninvasive technique with high temporal resolution. In addition, EEG requires low-cost hardware when compared with the other modalities such as functional Magnetic Resonance Imaging (fMRI), Positron Emission Tomography (PET), and Single Photon Emission Computed Tomography (SPECT). Moreover, the most common source models are discussed along with the used signal processing based techniques for source localization. In this work, distributed sources dipole model algorithms including the SAFFIRE and sLORETA are discussed and applied to simulated epileptic spikes. Upon examination of these algorithms, their potential in epilepsy source localization was proven with relatively low localization errors of 6.25 cm and 3.55 cm for sLORETA and SAFFIRE algorithms respectively. The SAFFIRE algorithm performance is investigated on epilepsy real data where the localized epileptogenic foci were consistent to the suggested locations by neurologists. Furthermore, the effect of reducing the number of electrodes on the source localization error was investigated on simulated epileptic spikes. The source localization error increased by 2.18 cm when reducing the number of electrodes from 256 down to 128. Then it increased by 3.7 mm when going from 128 electrodes to 64 electrodes. In conclusion, the localization error is inversely proportional to the number of electrodes used for recording brain potentials.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
Cytosolic Delivery of Doxorubicin from Liposomes to Multidrug-Resistant Cancer Cells via Vaporization of Perfluorocarbon Droplets
No full textA common mechanism of multidrug resistance is the upregulation of efflux pumps in the cancer cells that can more rapidly export unwanted materials (e.g. cancer drugs) out of the cell, compared to sensitive cancer cells. This research seeks to overcome this mechanism by vaporizing a perfluoropentane emulsion droplet inside of a drug-containing liposome (eLiposome) that was endocytosed into a cancer cell. Folate attached to the eLiposome facilitates uptake into the cell as observed by confocal microscopy. Ultrasound was examined as a trigger to initiate the vaporization of the perfluoropentane droplet and release doxorubicin from folated eLiposomes (feLD). Two seconds of ultrasound released 78% of encapsulated doxorubicin from feLD. Doxorubicin-sensitive KB-3-1 cells and doxorubicin-resistant KB-V1 cells treated with feLD (without ultrasound) had cell viabilities of 33% and 60%, respectively. Ultrasound had negligible additional effect on the cell viability of KB-3-1 and KB-V1 cells treated with feLD (33% and 53%, respectively). We hypothesized that the doxorubicin sulfate fibers that were formed during the loading of doxorubicin into the eLiposome present a site for heterogeneous nucleation once the feLD is endocytosed by the cell, and thus droplet vaporization occurs with or without ultrasound
A New Extension of Generalized Exponential Distribution with Application to Ozone Data
No full textIn this article, a new distribution, called transformed Generalized Exponential Distribution () is proposed. The distribution has simple closed forms pdf and cdf. Several properties of the distribution are studied including unimodality, moments, conditional moments, stochastic ordering and Shannon entropy. The distribution is capable of monotonically increasing, decreasing, bathtub and upside down shaped hazard rates. Furthermore, we discussed several methods of estimation for estimating the parameters. In particular, we compare, through simulation study, the performance of the maximum likelihood estimation, maximum product spacing estimation, ordinary and weighted least-squares estimation methods. Also, the average interval lengths and coverage rates of 95% confidence intervals, including boot-p and boot-t confidence intervals for different parameter values are provided. A real data set is used to illustrate the applicability of the proposed distribution
Enhancement of Mobile Robot Navigation and Localization
No full textA Master of Science thesis in Mechatronics Engineering by Abdulrahman M. Renawi entitled, "Enhancement of Mobile Robot Navigation and Localization," submitted in November 2017. Thesis advisor is Dr. Mohammad A. Jaradat and thesis co-advisor is Dr. Mamoun Abdel-Hafez. Soft and hard copy available.Nearly all mobile robots need the knowledge of the robot’s location with respect to the initial position or with respect to the control station position to be able to navigate. Many research projects are conducted to solve the localization and navigation problems, but they are all either specific for indoor or outdoor due to the limitations of the available localization sensors or with some precautions and delays for indoor-outdoor localization with switching in-between. This thesis presents a single low-cost approach for the enhancement of localization and navigation of wheeled mobile robots for indoor-outdoor environments. Using a ZED Camera, an Inertial Measurement Unit, a Global Positioning Sensor and wheels Encoders, filtered with a Kalman Filter with no switching, a trajectory controller is designed and implemented to guide the robot through experiments based on a system model, and it is proved to be stable and efficient. Simulations are carried out on a Gazebo simulator using a Robot Operating System, and field experiments were done on a Kobuki robot platform to validate the proposed controller. Sensors’ measurements are fused using Extended Kalman Filter and Unscented Kalman Filter due to the system’s non-linearity. Filters’ results are simulated on Matlab using field data which is proved to be stable. Then, the results are implemented to fuse sensors’ readings onboard and estimate the robot’s location in the local frame. Both filters show good accuracy with 0.13 meters in indoor experiments, 0.2 meters in outdoor experiments, and 0.6 meters in indoor-outdoor experiments. The Unscented Kalman Filter shows lower absolute true ground error values than the Extended Kalman Filter by 0.01 meters. The proposed approach is efficient for indoor, outdoor and indoor-outdoor scenarios. Indoor and outdoor results were outstanding. Indoor-outdoor experiments show promising results. In addition, Unscented Kalman Filter outperforms Extended Kalman Filter in true errors.College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR
Photocatalytic UV degradation of 2,3,7,8-tetrachlorodibenzofuran in the presence of silver zeolite
No full textSilver clusters were introduced into the framework of zeolite Y. Low-temperature solid-state luminescence indicates the formation of silver–silver excimers and exciplexes that were found to be activated at 250 and 300 nm, respectively. The photodegradation of a persistent halogenated organic pollutant, namely 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF), was studied in the presence and absence of two catalysts, namely including AgY1 and AgY2, under mid- and high energy: 302 and 254 nm, respectively. The results showed that in the absence of a catalyst, degradation under 254-nm UV light resulted in changes to the peak intensity as well as energy, while the 302-nm profile showed only loss in peak intensity. In the presence of either catalyst, a higher rate of degradation of the 2,3,7,8-TCDF was observed. The amount of the adsorbed 2,3,7,8-TCDF on the AgY1 and AgY2 catalyst was estimated to reach 37.9 and 18.9% of its initial concentration, respectively. The toxicity of the intermediate and resultant products was further analyzed with the aid of an enzyme-linked immunosorbent assay. The optical density showed that in contrast to all the samples, the TCDF irradiated with 254 nm in the presence of AgY2 was high at 40 min inferring a decrease in toxicity of the resultant product. The present work shows an innovative and cost-efficient technique for the removal of dioxins and furans from water sources