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Minimizing Deadline Misses of Mobile IoT Requests in a Hybrid Fog- Cloud Computing Environment
No full textA Master of Science thesis in Computer Engineering by Dalia Fatahelrahman Omer entitled, “Minimizing Deadline Misses of Mobile IoT Requests in a Hybrid Fog-Cloud Computing Environment”, submitted in May 2019. Thesis advisor is Dr. Raafat Aburukba and thesis co-advisor is Dr. Taha Landolsi. Soft and hard copy available.The emergence of Internet of Things (IoT) has led to the rise of a variety of applications with different characteristics and Quality of Service (QoS) requirements. Those applications require computational power and have time sensitive requirements. Cloud computing paradigm provides illusion to consumers with unlimited computation resource power. However, cloud computing fails to deliver on the time-sensitive requirements of applications. The main challenge in the cloud computing paradigm is the associated delays from the edge IoT device to the cloud data center and from the cloud data center back to the edge device. Fog computing extends limited computational services closer to the edge device to achieve the time sensitive requirement of applications. The introduction of fog computing raises other challenges that are addressed in this thesis such as the mobility of edge devices, and the collaboration of multiple fog nodes and the cloud to achieve the QoS requirements of applications. The purpose of this work is to propose a scheduling solution which adopts the three-tier fog computing architecture in order to satisfy the maximum number of requests given their deadline requirements. This work takes into consideration the setting of distributed schedulers at the fog tier, and the heterogeneous IoT devices with varying degrees of mobility at the edge tier. In this thesis, an optimization model using mixed integer programming is introduced to minimize deadline misses. The proposed model is then validated with an exact solution technique. The scheduling problem is known to be an NP-hard, and hence, exact optimization solutions are inadequate for large size problems. Given the complex nature of the problem, a heuristic approach using Genetic Algorithm (GA) is presented with static and dynamic implementation. The performance of the proposed GA was evaluated and compared against round robin and priority scheduling. The results show that the deadline misses of the proposed approach is 20% to 55% better than the other techniques.College of EngineeringDepartment of Computer Science and EngineeringMaster of Science in Computer Engineering (MSCoE
Few-cycle laser driven reaction nanoscopy on aerosolized silica nanoparticles
No full textNanoparticles offer unique properties as photocatalysts with large surface areas. Under irradiation with light, the associated near-fields can induce, enhance, and control molecular adsorbate reactions on the nanoscale. So far, however, there is no simple method available to spatially resolve the near-field induced reaction yield on the surface of nanoparticles. Here we close this gap by introducing reaction nanoscopy based on three-dimensional momentum resolved photoionization. The technique is demonstrated for the spatially selective proton generation in few-cycle laser-induced dissociative ionization of ethanol and water on SiO2 nanoparticles, resolving a pronounced variation across the particle surface. The results are modeled and reproduced qualitatively by electrostatic and quasi-classical mean-field Mie Monte-Carlo (M3C) calculations. Reaction nanoscopy is suited for a wide range of isolated nanosystems and can provide spatially resolved ultrafast reaction dynamics on nanoparticles, clusters, and droplets
The Use of Microwave Tomography in Bone Healing Monitoring
No full textA Master of Science thesis in Biomedical Engineering by Mohanad Ahmed Alkhodari entitled, “The Use of Microwave Tomography in Bone Healing Monitoring”, submitted in April 2019. Thesis advisors are Dr. Amer Zakaria and Dr. Nasser Qaddoumi. Soft and hard copy available.In this thesis, a numerical study is conducted to investigate the use of microwave tomography in monitoring bone health in human lower limbs. By monitoring bone volume fraction (BVF) and bone density, the effectiveness of Vitamin D treatment can be evaluated for osteoporosis patients. In microwave tomography, the leg is radiated with non-ionizing low-power electromagnetic signals with scattered electric fields measured at several locations surrounding the leg. Within the framework of inverse scattering problems, the measured fields are used as inputs for an optimization algorithm to estimate the location and electrical properties inside the human leg. In this work, three two-dimensional cross-sectional models of human leg at different fat thicknesses are created and simulated using a finite-element method, where the transverse magnetic approximation is applied. The synthetic results are then inverted using a finite-element contrast source inversion method. Furthermore, an enhancement procedure is followed to investigate the effect of incorporating prior information about the object-of-interest (OI), changing the boundaries of the imaging domain, relocating antennas, and using ultrasound gel as a matching medium. In addition, an image processing approach is provided to build estimated models to be used in the enhancement procedure. The final results show that variations in BVF affect the results of the inversion algorithm. The real part relative permittivity line plots showed a downward trend as the BVF increases, which can be related to an increase in the bone density. The outcomes of this thesis support the hypothesis that a MWT wearable system is useful for bone density monitoring application, and more specifically for Vitamin D treatment evaluation.College of EngineeringMultidisciplinary ProgramsMaster of Science in Biomedical Engineering (MSBME
Strength of Concrete Produced With Recycled Materials
No full textA Master of Science thesis in Civil Engineering by Mohamed Emad Ali entitled, “Strength of Concrete Produced with Recycled Materials”, submitted in December 2019. Thesis advisor is Dr. Sherif Yehia and thesis co-advisor is Dr. Farid Abed. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).Recent statistics predicts that the increasing demand of Natural Aggregate (NA) in construction industry to reach 66.2 billion metric tons by the year 2022. Several concerns were raised regarding the extinction of NA due to the increasing demand from the construction industry. Introducing Recycled Aggregate (RA), as replacement of NA, is certainly an important step towards sustainable development in the concrete industry and management of construction waste. RA from demolished concrete structures is an alternative to NA, which helps in the preservation of the environment. However, concrete produced by RA is affected by the variability of the aggregate properties. Properties of RA are influenced by previous loading, different environmental conditions, crushing process, contamination and impurities such as wood and plastic pieces. In addition, mortar adhered to RA lead to lower density, high absorption, and low resistance to degradation. Several research efforts indicated that concrete with comparable compressive strength to that achieved with NA could be produced by utilizing RA. However, durability and long-term performance of concrete made with RA need to be evaluated to ensure meeting the design requirements. The use of supplementary cementitious materials is one of the alternatives to improve concrete durability and cement replacement is another step towards sustainability. In this study, Ground-Granulated Blast-furnace Slag (GGBS) and Silica Fume will be used as partial replacement of cement to improve concrete made with RA. Several mixes with replacement of NA by RA will be prepared and exposed to three different conditions. Furthermore, as an approach to embrace sustainability, similar mixes will be prepared and evaluated using Treated Wastewater (TWW) that contains 670 ppm of dissolved solids. Based on the results the effect of replacing 50% of cement by GGBS and Silica increased the strength concrete by 17%. However, the effect of replacing 100% of NA with RA reduced the strength by 39%, in addition, the effect of replacing Tap Water (TW) with TWW in concrete mixing reduced the strength of NA concrete by 13% and RA concrete by 20%. The concrete where the concrete was produced with RA, GGBS/Silica, TWW and cured with TWW had a strength reduction of only 6% with respect to conventional concrete.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Pharmacognostic evaluation of Terminalia chebula standard extracts and finished products
No full textThe different commercial samples of Terminalia chebula (T. chebula) standard extracts and finished products were taken for elemental analysis studies and were evaluated by ICP-OES and compared with standard reference data. Trace elements are naturally occurring and its daily requirement as dietary supplement form is only a few milligrams and even micrograms. They are categorized as essential and non-essential, and that is based upon their biological action, diseases that occur due to their deficiency and toxicity due to overdose. Use of herbal medicines is now increasing worldwide because of their minimal side effects. In general, Haritaki (T. chebula) acts as a blood purifier and prevents haemorrhage. It is also used as an internal cleanser by removing harmful toxins and excess fats out of the body. It can strengthen the hair roots and enriches hair color. The elements were determined quantitatively using the modern technique of ICP-OES. The extracts undertaken for this study contains Ca as a primary elemental content, and its concentration is found to be as high as 144 mg/kg in comparison with other macro elements. Ca helps to overcome the problems of high blood pressure, heart attack, premenstrual syndrome, and colon cancer, besides its ability to keep the bones healthy and to reduce the risk of osteoporosis. Other essential elements such as Fe (2.0732 mg/kg), Zn (1.0235 mg/kg), and Mn (0.2500 mg/kg) were also present but not to an appreciable amount in the extracts of T. chebula. It was concluded that due to soil nature, climatic condition, time of harvest could be a detrimental factor while reviewing the elemental profile
Viscosity and Critical Properties of n-Decane, n-Pentadecane and n-Eicosane using Molecular Simulation
No full textA Master of Science thesis in Chemical Engineering by Ibrar Ul Samad entitled, “Viscosity and Critical Properties of n-Decane, n-Pentadecane and n-Eicosane using Molecular Simulation”, submitted in December 2019. Thesis advisor is Dr. Naif Darwish. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).Studies involving heavy hydrocarbons have been steadily increasing due to the increase in the extraction of shale or heavy oil of which heavy hydrocarbons are a major constituent. Experimental studies are difficult to conduct on species found in heavy oil because of thermal instability that results in their decomposition at high temperatures. This is especially true in the case of determining critical properties. Additionally, extraction of pure species from heavy oil is difficult due to the high energy requirements. Since they are extrapolative in nature, existing correlations can be used but with a certain degree of inaccuracy. This study uses molecular simulation, mainly molecular dynamics, to predict viscosity, saturated liquid and vapor densities, and critical properties of three pure heavy n-alkanes, namely, n-decane, n-pentadecane and n-eicosane. The viscosity was predicted as a function of temperature using equilibrium molecular dynamics with the Green-Kubo relations and the AMBER force-field. Comparison with experimental data showed that the AMBER force-field predicts reasonably the viscosity of smaller molecules at higher temperatures. The percentage deviation for n-decane was 40% at 300 K and 25% at 500 K. On the other hand, for n-pentadecane and n-eicosane, the percentage deviations were 34.7% at 550K and 76.2% at 600 K, respectively. For the critical properties, which were determined from the simulated saturated liquid and vapor densities, AMBER, COMPASS and TraPPE force fields were employed. For all three force fields, the methodology of volume-expansion molecular dynamics was used, while the Gibbs ensemble Monte Carlo technique was used with the AMBER force field. The results were compared with experimental data, as well as with those from several correlations and equations-of-state. The results show that the TraPPE force field is the most accurate in predicting critical properties (less than 10% deviation), followed by AMBER (less than 20% deviation, except for the critical pressures for n-eicosane) and COMPASS (up to 24% deviation). Finally, a comparison was made for the needed computational time; COMPASS required the largest execution time, followed by AMBER and TraPPE.College of EngineeringDepartment of Chemical EngineeringMaster of Science in Chemical Engineering (MSChE
Seasonal Variability of Retroflection Structures and Transports in the Atlantic Ocean as Inferred from Satellite-Derived Salinity Maps
No full textThree of the world’s most energetic regions are in the tropical and South Atlantic: the North Brazil Current Retroflection, the Brazil-Malvinas Confluence, and the Agulhas Current Retroflection. All three regions display offshore diversions of major boundary currents, which define the intensity of the returning limb of the Atlantic meridional overturning circulation. In this work, we use a sea-surface salinity (SSS) satellite product, combined with a high-resolution numerical model and in situ measurements, in order to explore the seasonal variation of the surface currents and transports in these three regions. The analysis of the model output shows that the SSS patterns reflect the surface velocity structure, with the largest horizontal SSS gradients coinciding with those areas of highest velocity and the most predominant velocity vector being 90° anticlockwise (clockwise) from the horizontal SSS gradient in the northern (southern) hemisphere. This information is then applied to the SSS satellite product to obtain maps of water velocity and salt transports, leading to a quantitative tool to estimate both water and salt transports in key regions of the world ocean
Operation of Battery Exchange Stations for Electric Vehicles
No full textA Master of Science thesis in Electrical Engineering by Ghady Khalil Zaher entitled, “Operation of Battery Exchange Station for Electric Vehicles”, submitted in May 2019. Thesis advisor is Dr. Mostafa Shaaban. Soft and hard copy available.Due to environmental and energy security concerns, low emission vehicles present a vital necessity for clean transportation. In particular, Electric Vehicles (EV) are the most promising solution due to the fact that the electrical power system is the most ready infrastructure to supply their requirement. Two possible energy delivery solutions to the EVs, namely the charging stations and the Battery Exchange Stations (BES), are taking the interest of the research nowadays. In this research, a new operation approach is proposed for the BESs. The proposed approach models and optimizes the performance of the charging, discharging and the replacement of the batteries throughout the day taking into consideration the customers arrivals to the BES. The main targets of this approach are to satisfy the EV owners charging requests and to minimize the operating costs. In addition, the batteries in possession of the BES are used to secure more profit to the investor by performing energy arbitrage and supplying ancillary services to the grid. This thesis is targeting the EV manufacturers and EV charging service providers who are directly affecting the development of the EV market. The BES operation optimization problem is formulated as mixed-integer nonlinear programming and is solved as a day-ahead operational problem. The behaviour of charging/discharging power, the state of charge and the stored and replaced energy for all batteries in the station is observed for different case studies. The effect of different aspects such as the grid power limitation, solar photovoltaic system addition and battery self-degradation on the operation of the BES is designed and discussed. Also, a comparison between the charging station operation and the BES is conducted and the results show the benefits of implementing the concept of BES on the EV market. The results prove the effectiveness of the proposed approach in satisfying the EV owners and maximizing the BES investor profit.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
An Investigation of Links Between Transport Choices and Health: A Case Study in the UAE
No full textA Master of Science thesis in Civil Engineering by Mohamed Tarish AlQahtani entitled, “An Investigation of Links Between Transport Choices and Health: A Case Study in the UAE”, submitted in April 2019. Thesis advisor is Dr. Ghassan Abu-Lebdeh. Soft and hard copy available.This research examines the relationship between transport/travel choices-- as default decisions that are decidedly influenced by the built environment-- and public health in the UAE. The objective of the research is two-fold: 1) evaluate the links between travel/transport choices and public health in working adults and college-age residents of the UAE, and 2) develop meaningful correlations between specific public health markers and transport choices and socio-economic characteristics. A self-administered survey was used to collect information on lifestyle with an emphasis on travel/transport choices and on specific health outcomes as Non-contagious illnesses (also known as modernity illnesses). 1009 persons participated in the survey. Among the more pronounced observations is the high proportion of commuters exposed to traffic congestion (76%), and those reporting stress (72%). Back-propagation neural network models were developed to help predict health outcomes from travel/transport choices and socio-economic characteristics. Over thirty models usable were developed which can be integrated into a transport planning/policy framework thus enabling direct inclusion of public health outcomes in the transportation planning and/or decision-making process. Predictive quality and strength of the models were assessed using the coefficient of determination, R2, distribution of error (residuals vs. independent variables), and the mean squared error (MSE).College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Modeling and Bias-Robust Estimation of the Acoustic Release of Chemotherapeutics from Liposomes
No full textThis paper models the acoustic drug release of chemotherapeutics from liposomes using a kinetic model that accounts for systematic biases affecting the drug delivery process. An optimal stochastic filter is then proposed to provide robust estimates of the percent drug released. Optimality is guaranteed by accurately identifying the underlying statistical noise characteristics in experimental data. The estimator also quantifies the bias in the release, exhibited by the experimental data. Drug release is experimentally measured as a change in fluorescence upon the application of ultrasound. First, a first-order kinetic model is proposed to model the release, which is aided by a bias term to account for the fact that full release is not achieved under the conditions explored in this study. The noise structure affecting the process dynamics and the measurement process is then identified in terms of the statistical covariance of the measured quantities. The identified covariance magnitudes are then utilized to estimate the dynamics of drug release as well as the bias term. The identified a priori knowledge is used to implement an optimal Kalman filter, which was initially tested in a simulation environment. The experimental datasets are then fed into the filter to estimate the state and identify the bias. Experiments span a number of ultrasonic power densities for liposomes. The results suggest that the proposed algorithm, the optimal Kalman filter, performs well in modeling acoustically activated drug release from liposomes