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Video Streaming over D2D Networks
No full textA Master of Science thesis in Electrical Engineering by Ibtihal Mohamed Taha Ahmed entitled, “Video Streaming over D2D Networks”, submitted in April 2019. Thesis advisor is Dr. Mahmoud H. Ismail Ibrahim and thesis co-advisor is Dr. Mohamed S. Hassan. Soft and hard copy available.Device-to-Device (D2D) communication has been presented as an innovation that can improve the cellular network performance by exploiting the proximity-based service between closely-located devices. Enabling D2D communication increases the energy efficiency, improves the capacity of the network and reduces the communication delay. Despite the above-mentioned advantages, D2D communication presents some challenges, for example, the need for proper interference management, power control, mode selection and device discovery. Nowadays, the increasing demand for video streaming has led to rapid growth in data traffic that is unable to be handled by traditional networks. Consequently, many works in the literature suggested employing D2D communication for video transmission to offload the cellular network and enhance the quality of video streaming. Moreover, the emergence of video-based applications has stimulated the need for high-performance D2D communication. This thesis focuses on video streaming over D2D communications underlaying a Long Term Evolution (LTE) network where Scalable Video Coding (SVC) is assumed. In particular, joint resource allocation, mode selection and power control for multiple D2D pairs are addressed. The objective is to maximize the throughput of D2D pairs while considering the minimum data rate requirements by both the Cellular Users (CUs) as well as the D2D pairs and maintain video quality and continuity. Resources are allocated to each CU and D2D pair in three modes of operation; cellular, dedicated and reuse and a mode selection algorithm is implemented. Furthermore, a packet-layer video assessment model is applied to predict the impact of network conditions on video quality. Finally, the effect of mobility on mode selection is examined. The performance of the proposed scheme is evaluated through extensive simulations and compared to the scenarios where only one mode of transmission is used for all D2D pairs. Simulation results show that mode selection improves the throughput of D2D pairs while providing better video quality. We assess the effect of user mobility on system performance and observe quality degradation for high mobility scenario.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
Notch Sensitivity of Fiber Reinforced Composite
No full textA Master of Science thesis in Mechanical Engineering by Mostafa Elyoussef entitled, “Notch Sensitivity of Fiber Reinforced Composite”, submitted in April 2019. Thesis advisor is Dr. Maen Alkhader and thesis co-advisor Dr. Wael Abuzaid. Soft and hard copy available.In most applications, structures made of composite materials involve features such as drilled assembly holes, which induce stress concentrations in their vicinities resulting in a reduction in the load carrying capacity of the structure. The nature of the damage resulting from such geometric features in orthotropic CFRP composites has been the subject of extensive research. Nevertheless, few works have investigated the behavior of notched CFRP composites exposed to elevated temperatures. Accordingly, the aim of this research is to investigate the effect of elevated temperatures on the notch sensitivity of CFRP composites. To achieve the goal of this study, both the nominal and local responses of woven CFRP samples were experimentally investigated, with the aid of Digital Image Correlation technique (DIC). Tensile tests were conducted on notched (i.e. with circular hole) and un-notched samples at 25°C, 50°C, 75°C, and 100°C. The experimental results obtained from the global stress-strain response of un-notched samples showed a decreasing trend in the mechanical properties with increasing temperatures. However, the global response of notched samples at 50°C surprisingly deviated from the expected trend and exhibited higher tensile strength than that at 25°C. Moreover, the notch sensitivity, assessed through un-notched to notched strength ratio, was found to decrease with increasing temperatures. Fractured surface examination showed two different damage mechanisms: Transverse cracks and axial splitting. It was noticed that transverse cracks was evident at the four temperature levels, while axial splitting was absent at room temperature. Measuring the local axial strains at the transverse crack initiation site showed a clear deviation from the linear response at the onset of transverse cracking. Moreover, investigating the local response at the axial splitting initiation site revealed a sudden change in the transverse and shear strain evolution. The blunting effect of axial splitting was found to become more significant at higher temperatures. Furthermore, residual shear strains were measured at the end of loading-unloading cycle for different temperature levels. It was found that residual strains are negligible at room temperatures and become more significant at higher loading temperatures.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Ultrasonically Controlled Albumin-conjugated Liposomes for Breast Cancer Therapy
No full textTargeted liposomes have high potentials in the specific and effective delivery of their loaded therapeutic agents to the tumor site. Once at the tumor site, it is important that these liposomes are triggered to release their load in a controlled and effective manner. In this study, pegylated (stealth) liposomes conjugated to human serum albumin (HSA) were investigated for the delivery of a model drug (calcein) to breast cancer cells. The fluorescent results showed that calcein uptake by the two breast cancer cell lines (MDA-MB-231 and MCF-7) was significantly higher with the HSA-PEG liposomes compared to the non-targeted control liposomes. Furthermore, the exposure to low-frequency ultrasound (LFUS) resulted in a statistically significant uptake of calcein compared to the uptake without ultrasound. The described drug delivery (DD) system, which involves combining the targeted liposomal formulation with ultrasonic triggering techniques, promises a safe, effective and site-specific breast cancer therapy
Factors affecting sedimentational separation of bacteria from blood
No full textRapid diagnosis of blood infections requires fast and efficient separation of bacteria from blood. We have developed spinning hollow disks that separate bacteria from blood cells via the differences in sedimentation velocities of these particles. Factors affecting separation included the spinning speed and duration, and disk size. These factors were varied in dozens of experiments for which the volume of separated plasma, and the concentration of bacteria and red blood cells (RBCs) in separated plasma were measured. Data were correlated by a parameter of characteristic sedimentation length, which is the distance that an idealized RBC would travel during the entire spin. Results show that characteristic sedimentation length of 20 to 25 mm produces an optimal separation and collection of bacteria in plasma. This corresponds to spinning a 12-cm-diameter disk at 3,000 rpm for 13 s. Following the spin, a careful deceleration preserves the separation of cells from plasma and provides a bacterial recovery of about 61 ± 5%
IoT-solar energy powered smart farm irrigation system
No full textAs the Internet of things (IoT) technology is evolving, distributed solar energy resources can be operated, monitored, and controlled remotely. The design of an IoT based solar energy system for smart irrigation is essential for regions around the world, which face water scarcity and power shortage. Thus, such a system is designed in this paper. The proposed system utilizes a single board system-on-a-chip controller (the controller hereafter), which has built-in WiFi connectivity, and connections to a solar cell to provide the required operating power. The controller reads the field soil moisture, humidity, and temperature sensors, and outputs appropriate actuation command signals to operate irrigation pumps. The controller also monitors the underground water level, which is essential to prevent the pump motors from burning due to the level in the water well. The proposed system has three modes of operations, i.e. the local control mode, mobile monitoring-control mode, and fuzzy logic-based control mode. For the purpose of the proposed system validation, a prototype was designed, built, and tested.American University of Sharja
Emotion Recognition Based on Fusion of Local Cortical Activations and Dynamic Functional Networks Connectivity: An EEG Study
No full textIn this paper, we present a method to improve emotion recognition based on the fusion of local cortical activations and dynamic functional network patterns. We estimate the cortical activations using power spectral density (PSD) with the Burg autoregressive model. On the other hand, we estimate the functional connectivity networks by utilizing the phase locking value (PLV). The results of cortical activations and connectivity networks show different patterns across three emotions at all frequency bands. Similarly, the results of fusion significantly improve the classification rate in terms of accuracy, sensitivity, specificity and the area under the receiver operator characteristics curve (AROC), p < 0:05. The average improvement with fusion in all evaluation metrics are 6.84% and 4.1% when compared to PSD and PLV alone, respectively. The results clearly demonstrate the advantage of fusion of cortical activations with dynamic functional networks for developing human-computer interaction system in real-world applications
Joint Planning of Smart EV Charging Stations and DGs in Eco-Friendly Remote Hybrid Microgrids
No full textThis paper proposes an efficient planning algorithm for allocating smart electric vehicle (EV) charging stations in remote communities. The planning problem jointly allocates and sizes a set of distributed generators (DGs) along with the EV charging stations to balance the supply with the total demand of regular loads and EV charging. The planning algorithm specifies optimal locations and sizes of the EV charging stations and DG units that minimize two conflicting objectives: (a) deployment and operation costs and (b) associated green house gas emissions, while satisfying the microgrid technical constraints. This is achieved by iteratively solving a multi-objective mixed integer non-linear program. An outer sub-problem determines the locations and sizes of the DG units and charging stations using a non-dominated sorting Genetic algorithm (NSGA-II). Given the allocation and sizing decisions, an inner sub-problem ensures smart, reliable, and eco-friendly operation of the microgrid by solving a non-linear scheduling problem. The proposed algorithm results in a Pareto frontier that captures the trade-off between the conflicting planning objectives. Simulation studies investigate the performance of the proposed planning algorithm in order to obtain a compromise planning solution.Qatar National Research Fun
Novel insights into the potential role of ion transport in sensory perception in Acanthamoeba
No full textBackground: Acanthamoeba is well known to produce a blinding keratitis and serious brain infection known as encephalitis. Effective treatment is problematic, and can continue up to a year, and even then, recurrence can ensue. Partly, this is due to the capability of vegetative amoebae to convert into resistant cysts. Cysts can persist in an inactive form for decades while retaining their pathogenicity. It is not clear how Acanthamoeba cysts monitor environmental changes, and determine favourable conditions leading to their emergence as viable trophozoites. Methods: The role of ion transporters in the encystation and excystation of Acanthamoeba remains unclear. Here, we investigated the role of sodium, potassium and calcium ion transporters as well as proton pump inhibitors on A. castellanii encystation and excystation and their effects on trophozoites. Results: Remarkably 3′,4′-dichlorobenzamil hydrochloride a sodium–calcium exchange inhibitor, completely abolished excystation of Acanthamoeba. Furthermore, lanthanum oxide and stevioside hydrate, both potassium transport inhibitors, resulted in the partial inhibition of Acanthamoeba excystation. Conversely, none of the ion transport inhibitors affected encystation or had any effects on Acanthamoeba trophozoites viability. Conclusions: The present study indicates that ion transporters are involved in sensory perception of A. castellanii suggesting their value as potential therapeutic targets to block cellular differentiation that presents a significant challenge in the successful prognosis of Acanthamoeba infections
Real Time Li-ion Battery Bank Parameters Estimation for Electric Vehicle Traction System
No full textA Master of Science thesis in Electrical Engineering by Hafiz Muhammad Usman Butt entitled, “Real Time Li-ion Battery Bank Parameters Estimation for Electric Vehicle Traction System”, submitted in May 2019. Thesis advisor is Dr. Shayok Mukhopadhyay and thesis co-advisor is Dr. Habibur Rehman. Soft and hard copy available.This work focuses on accurate and efficient real-time estimation of Li-ion battery model parameters for electric vehicle (EV) traction systems. The contributions made by this thesis are: accurate estimation of Li-ion battery parameters using a two-stage adaptive optimization strategy, which minimizes the need of offline processing, and enables efficient real-time estimation of Li-ion battery model parameters for EV traction systems. In the first part of this thesis, a two-stage universal adaptive stabilizer (UAS) based optimization technique is proposed for estimation of Li-ion battery model parameters. The first stage utilizes a UAS based APE technique to acquire an initial estimate of battery parameters. The second stage utilizes one of the three different optimization techniques, i.e., fmincon, particle swarm optimization (PSO), and hybrid PSO to improve the accuracy of battery model parameters obtained by the APE. The parameters estimated by the APE help in reducing the search space interval required by the optimization technique, thus reducing the computation time for the optimization process. This thesis presents detailed comparison of experimental results using the proposed approach, and other well-known optimization techniques from the literature. In the second part of this thesis, a modification to the existing UAS based APE strategy is proposed. The existing UAS based APE strategy requires a small amount of prior offline experimentation and some post-processing to determine some of the battery parameters. However, the proposed modified APE strategy estimates all battery parameters in a single experimental run. Mathematical proofs, simulation and experimental results supporting the proposed modified APE strategy are also presented. In the third part of this thesis, the modified APE strategy is employed for real-time parameters estimation of a 400 V, 6.6 Ah Li-ion battery bank, which supplies power to a field-oriented control based EV drive system. Some of the distinct features of the modified APE strategy, such as simple real-time implementation, fast convergence, and minimal experimental effort, show the effectiveness of the modified APE strategy developed in this work for real-time Li-ion battery model parameters estimation of EV traction systems.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
The Impact of Innovation on The Competitiveness of Building Construction Projects
No full textA Master of Science thesis in Civil Engineering by Sabreen Fayiz Dar Amer entitled, “The Impact of Innovation on The Competitiveness of Building Construction Projects”, submitted in July 2019. Thesis advisor is Dr. Salwa Beheiry and thesis co-advisor is Dr. Jamal El-Din Abdalla. Soft and hard copy available.The construction industry contributes immensely to the socioeconomic development of nations by building extensive infrastructure and production facilities. Additionally, this industry, being the largest employer worldwide, supports all other industries and strengthens labour markets. Hence, this study is focused on the relationship between innovation in construction and construction projects’ cost and schedule competitiveness. The research premise relies on projects’ and programs’ competitiveness influencing national construction activity, and ultimately boosting national economies and Gross Domestic Products (GDPs). The research created a novel methodology, using the triangulation method, to measure the use of innovative technology, techniques, and practices, in planning and executing building construction projects and examined the effect of this usage level on project competitiveness. Which results in creating Innovation in Construction Index tool (ICI) that measures innovation in any building construction project. This specific link had not been fully investigated in the relevant literature. The work done to date involved a few key attributes of innovation in the construction industry, so this study built on previous work by creating a complete framework for measuring the usage of key innovation attributes and designing a predictive model including cost and schedule competitiveness using linear regression by SAS. This model should assist in the decision-making process at owner, developer, and contractor companies, during the planning and execution of heavily funded projects. The ripple effect of this research should also extend to national policy via the local and national industry adaptation of the techniques and technologies.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE