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An optimal resource allocation for future parking lots with charger assignment considering uncertainties
No full textThis paper proposes a new planning approach for different types electric vehicle (EV) chargers’ allocation in conjunction with photovoltaic (PV) panels. The proposed approach helps to upgrade the infrastructure satisfying the demand for high penetration of EVs with least expansion cost. This approach proposes a routing signal for the arriving EV at the parking lot to guide them to a suitable charger according to the charger and EV battery statuses. The proposed signal increases the utilization EV chargers. Also, the planning approach jointly considers the PV allocation to provide more energy and power capacity for chargers and to reduce overall energy cost. This proposed approach considers coordinated charging /discharging, creating bidirectional power flow between the grid and the EVs. The planning problem is formulated as a mixed-integer nonlinear program to maximize the net annual revenue. A Markov Chain Monte Carlo (MCMC) simulation technique is utilized to account for the uncertainties associated with the PV generation and the power demand. The outcome of the approach can be described as the optimal quantity and types of EV chargers, along with the optimal sizing of the allocated PV panels. A Multi-case simulation is done to demonstrate the effectiveness of the proposed approach
A review of post-consumption food waste management and its potentials for biofuel production
No full textThe global world production of food waste is expected to increase by 33% within the next decade. The current annual food waste stands at around 1.6 billion tonnes, which is worth around $ 1.2 trillion loss. Out of this, nearly 50%–60% comes from post-consumption waste (leftover). Besides, food waste is causing serious environmental concerns as it contributes to the total global greenhouse gas emissions. This paper is focused on reviewing the latest trends and challenges in post-consumption food waste management and assessing its potentials for the production of biofuel and biochar. This includes identifying the major characteristics of post-consumption food waste, disposal methods (landfill, animal feed, and donation) and recycling through chemical, biological and thermochemical conversion. The review indicates that recycling through integrated pyrolysis-gasification processes can lead to the production of multiple high-value products (biofuel, biochar/ash and water) with almost zero or negative impact on the environment. The biochar and water have great potentials in soil amendment, thus, extending the benefits of food waste to increasing water resources, livestock and food security, especially in arid and semi-arid regions. Similarly, integrated transesterification and anaerobic digestion may allow overcoming some of the negatives associated with the standalone implementation of these technologies. However, the implementation of modern food waste management technologies is hindered by the lack of standard processing procedures due to the regional diversity of the food waste characteristics. Besides, there are social and technical challenges associated with the lack of proper post-consumption food waste segregation mechanism at the industrial and community levels, as well as the lack of sufficient research on sustainability and life cycle assessment (LCA) of the food waste management options
Design and Comparison Analysis of Various Flow Configurations in Bipolar Plates via Numerical Simulation
No full textBipolar plates play a major role in the overall performance of fuel cells, hence their proper design and optimization are essential. In this regard, pressure drop across bipolar plates has a major impact on the efficiency. Therefore, it is crucial to minimize the friction between the plate walls and the working fluid, with a proper flow configuration, to eliminate pressure drops. The study, involved the simulation of various modified pin-flow bipolar plate configurations where a comparative analysis was carried out. A parametric study was performed to optimize various designs and operating parameters such as fluid flow, velocity and pressure. Computational fluid dynamics (CFD) was employed for the numerical simulation to ensure the optimum uniformity of fluid distribution. Results showed that the pressure drop is proportional to the velocity magnitude in the laminar region. Moreover, the pressure drop was minimized by eliminating the sharp edges in the flow channels
Lessons learned from the underrepresentation of women in STEM: AI-enabled solutions and more
No full textThe absence of women in STEM and energy sectors is driven by discrimination and socio-cultural factors. A greater number of women “leak out” from Energy and STEM fields than men. AI-enabled solutions offer analysis tools to measure and evaluate diversity and inclusion
Compressive Behavior of Slender Circular Columns with Double GFRP Spirals and Bars
No full textA Master of Science thesis in Civil Engineering by Yousef Ayman Awera entitled, “Compressive Behavior of Slender Circular Columns with Double GFRP Spirals and Bars”, submitted in April 2021. Thesis advisor is Dr. Mohammad AlHamaydeh. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Despite the recent research efforts and developments, many building codes and standards, e.g. ACI 440.1R-15 and CSA S806-12, recommend ignoring Fiber Reinforced Polymer (FRP) reinforcement in design for compression. This research investigates the feasibility of utilizing Glass Fiber Reinforced Polymer (GFRP) rebars as compression and confinement reinforcement in slender circular RC columns, subjected to concentric loading. A group of 18 circular columns are instrumented and tested to failure in axial compression. The specimens’ reinforcements (longitudinal bars and spirals) were mainly arranged in double layers and compared to single layer control counterparts. The double-layer longitudinal reinforcements were all-GFRP, all-steel, or hybrid (outer GFRP layer and inner steel layer). The slenderness ratio of all columns is 38.5, made of 21 MPa concrete. The investigated parameters included: reinforcement type (steel/GFRP), ratio, and configuration (single/double-layer); spiral pitch and diameter. Upon conclusion, it is found that substantial improvements to confinement and ductility levels are directly associated with double-layer configurations. This cannot be achieved unless the recommended maximum spiral pitch (75 mm) is maintained. At higher pitch values, the double-layered hybrid columns outperformed their all-GFRP counterparts. This could be attributed to the greater confinement provided by the higher modulus of elasticity of the inner steel reinforcement and the additional concrete volume surrounding it, thus minimizing the potential for rebar local buckling. Moreover, at constant volumetric reinforcement ratios, smaller diameter spirals at smaller pitches greatly outperform larger diameters at higher pitches. Furthermore, when the 75 mm pitch limit is maintained, single and double-layer GFRP specimens successfully achieved higher strength, confinement, and ductility compared to their steel or hybrid counterparts. Reliable performance of the GFRP reinforcement in compression is demonstrated in this experimental study. It may be attributed to substantial improvements achieved in GFRP quality and manufacturing processes. Future studies are expected to provide further confirmation that GFRP reinforcement can be reliably used in compression design.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Optimal operation of battery exchange stations for electric vehicles
No full textDue to environmental and energy security concerns, low emission vehicles present a vital necessity for clean transportation. In particular, electric vehicles (EVs) 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 (BESs) are the focus of research nowadays. In this paper, a new optimal operation approach is proposed for the BESs. The proposed new model determines the optimal charging, discharging, and exchange decisions for the battery stock throughout the day taking into consideration the customers’ arrivals, the variations in the grid price, the grid connection limitations, and the self-degradation of the batteries. The objective of the proposed approach is to maximize the BES owner profit while satisfying the EV owners’ requests. The BES operation optimization problem is formulated as mixed-integer programming (MIP) problem and is solved as a day-ahead scheme. The performance of the BES is compared to conventional EV charging stations, where the BES shows superior customer satisfaction and higher profit
Optimal Operation and Planning of Power System Integrated with Reverse Osmosis Water Desalination
No full textA Master of Science thesis in Electrical Engineering by Zahra Hassan Abdallah Hassan Alnahhal entitled, “Optimal Operation and Planning of Power System Integrated with Reverse Osmosis Water Desalination”, submitted in December 2021. Thesis advisor is Dr. Mostafa Shaaban. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).The typical desalination for seawater in the Gulf area relies on thermal desalination, where the water and electricity are co-generated from fossil fuel thermal plants. These thermal plants are well known to increase CO2 emissions, and therefore the refuge to renewable energy resources is necessary to date to lower these emissions. However, the generation of renewable resources will not be propitious for thermal desalination. Therefore, other desalination techniques, such as the reverse osmosis (RO) desalination technique which is a harvesting electricity method, can be a beneficial way to utilize this excess renewable generation. To achieve this, the expression of water-energy-nexus (WEN) blossoms, which is the integration of water and electrical systems together, by the co-optimization of these two systems can mitigate the conventional ways defects. This thesis proposes new approaches for the operation and planning phases to co-optimize the water and electric power systems. The proposed approach leverages the operational pliability granted from the desalination tracks in conjunction with water storage tanks and variable speed pumps for the operation phase. Therefore, the operating costs of the electric and water networks can be minimized while considering the essential constraints of both systems, thus optimizing the operation of the two systems without jeopardizing the energy and water supplied to customers. Further, a mixed-integer nonlinear programming model is proposed for the day optimal operation of the two integrated systems. The simulation results were conducted on the IEEE 24-bus power system and a 15-node test water system supplied from a 4-track RO desalination plant. While in the planning phase, the proposed approach aims to size and allocate resources in the WEN system. On the electrical side, the planning approach optimally allocates photovoltaic (PV) generation and battery storage units while it allocates RO desalination plants in the waterside. The proposed approach utilizes Monte Carlo Simulation (MCS) to address the variability and uncertainty associated with electricity, PV generation, and water demand. Simulation results prove the effectiveness of the proposed operation approach in minimizing the operating costs of the WEN system by 4.6%.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
A Data Analytics Approach for Forecasting Cash Flow in Construction Projects
No full textA Doctor of Philosophy Dissertation in Engineering Systems Management by Hasan S. Mahmoud entitled, “A Data Analytics Approach for Forecasting Cash Flow in Construction Projects”, submitted in March 2021. Dissertation advisor is Dr. Vian Ahmed and dissertation co-advisor is Dr. Salwa M. Beheiry. Soft copy is available (Thesis, Completion Certificate, and AUS Archives Consent Form).The construction industry is one of the most crucial sectors in any economy. The construction industry leads the development of the underlying infrastructure in all regions, including the industrial, transportation, environmental, and commercial elements. The construction industry also fosters and executes capital-intensive projects that strengthen governmental and multinational corporate performance. Furthermore, the construction industry is considered the largest employer worldwide, engaging and training various technical and vocational expertise. Hence, it is vital that the industry maintains its financial, competitive advantage and sustains its operations. This competitive advantage is the aggregate performance of individual projects and collective programs. As such, there is a continuous and robust need for owners/developers to more accurately forecast, monitor, and control project performance. Many tools have been developed to monitor both the cost and the schedule performance of construction projects. Nevertheless, most lacked a comprehensive integration of risk factor quantification tools and the inclusion of owner-tailored input, particularly in cash flow monitoring and prediction. Therefore, this research aims to develop an "owner perspective" cash flow prediction framework that uses project performance data, and employs iterative fuzzy stochastic techniques to construct and model cost data to make more accurate cash flow estimates. To that aim, the study created, validated and tested a Cash Flow Risk Index (CFRI) that integrated relevant risk factors and collected and modeled project data to analyze contractors' default probabilities and predict time and cost overruns. Moreover, the study also created a metric to measure the response of project owners towards the identified risk and their response strategy. The research also designed an interactive tool for owner/developers to use on single/multiple projects or comprehensive programs. The developed model also allows the monitoring and controlling of the financial performance of the project during the time of operations. The results of the case study investigated here showed that the better quantification of risk factors leads to more accurate cash flow estimates by an increase in cash flow estimation accuracy of more than 30%.College of EngineeringMultidisciplinary ProgramsPhD in Engineering - Engineering Systems Management (PhD-ESM
Classifying Maqams of Qur'anic Recitations Using Deep Learning
No full textThe Holy Qur’an is among the most recited and memorized books in the world. For beautification of Qur’anic recitation, almost all reciters around the globe perform their recitations using a specific melody, known as maqam in Arabic. However, it is more difficult for students to learn this art compared to other techniques of Qur’anic recitation such as Tajwid due to limited resources. Technological advancement can be utilized for automatic classification of these melodies which can then be used by students for self-learning. Using state-of-the-art deep learning algorithms, this research focuses on the classification of the eight popular maqamat (plural of maqam). Various audio features including Mel-frequency cepstral coefficients, spectral, energy and chroma features are obtained for model training. Several deep learning architectures including CNN, LSTM, and deep ANN are trained to classify audio samples from one of the eight maqamat . An accuracy of 95.7% on the test set is obtained using a 5-layer deep ANN which was trained using 26 input features. To the best of our knowledge, this is the first ever work that addresses maqam classification of Holy Qur’an recitations. We also introduce the “Maqam-478” dataset that can be used for further improvements on this work.American University of Sharja
Evaluating velocity and temperature fields for Ranque Hilsch vortex tube using numerical simulation
No full textIn this study, a three-dimensional numerical investigation is carried out to study the flow field inside a Ranque-Hilsch vortex tube (RHVT) model. Flow parameters such as velocity, temperature, and pressure are plotted at various locations inside the tube. The study reports the effect of cold mass fraction on the energy separation of vortex tube . The results show that the flow inside RHVT consists of a free vortex from r/R=0 to 0.9 and a force vortex from r/R=0.9 to 1 and that heat transfer occurs from the inner core to the periphery of the tube. Furthermore, it is observed that the minimum cold temperature and the maximum hot temperature are achieved at different mass fractions, 0.19 and 0.8, respectively