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Project Planning and Control Models for Sustainable Construction Projects
No full textA Doctor of Philosophy Dissertation in Engineering Systems Management by Sareh Rajabi entitled, “Project Planning and Control Models for Sustainable Construction Projects”, submitted in May 2022. Dissertation advisor is Dr. Sameh El-Sayegh and dissertation co-advisor is Dr. Lotfi Romdhane. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Several researches investigated the integration of sustainability in construction. However, there is a gap in addressing the performance measurement and evaluation during the construction phase. Traditional project performance evaluation methods are used to assess time, cost, and scope performance. The main goal of this dissertation is to develop a new project controls model for sustainable construction projects by integrating time, cost, and sustainability. The proposed methods enhance the planning and controlling of sustainable construction projects. Twenty-two sustainability indicators under two groups environmental and socio-economic were identified based on a comprehensive literature review. The importance of indicators was then evaluated through a survey in the United Arab Emirates (UAE) using pair-wise comparison and the Analytic Hierarchy Process (AHP). The results highlighted that the use of renewable energy indicator was ranked as the most important with a global weight of 0.164 (environmental group). The construction site safety indicator was the most important, with a global weight of 0.093, in the socio-economic group. Three time-cost-sustainability optimization models are then developed for project planning. Model A introduces sustainability as a constraint, where the cost of the project is minimized while ensuring a minimum value of sustainability for the project. In Model B the objective function is formulated as a combination of the cost of the project and the equivalent cost of sustainability. These two optimization problems were solved using Linear Programming (LP) and the Genetic Algorithms (GA). For Model C, the problem is formulated as a multi-objective optimization problem, where the objective is to find the best compromise that minimizes the cost of the project while ensuring the highest value of sustainability. A case study is presented to demonstrate the application of the proposed models. A Sustainable Earned Value Management (SEVM) model was developed to monitor the attainment of sustainability objectives in construction projects in addition to the traditional objectives. The research is valuable as it encourages contractors to consider sustainability as a key objective resulting in more a sustainable construction industry. The research fills a recognized gap in the literature and proposes a set of sustainability indicators and project control models.College of EngineeringDepartment of Industrial EngineeringPhD in Engineering - Engineering Systems Management (PhD-ESM
INScription: Department of International Studies (INS) Issue #8 (September 29, 2022, Issue 1)
No full textCollege of Arts and SciencesDepartment of International Studie
Optimizing the Energy Production for a Photovoltaic Thermal (PVT) Water System
No full textA Master of Science thesis in Mechanical Engineering by Khader M.J. Alsayegh entitled, “Optimizing the Energy Production for a Photovoltaic Thermal (PVT) Water System”, submitted in May 2022. Thesis advisor is Dr. Mohamed O. Hamdan and thesis co-advisor is Dr. Mehmet F. Orhan. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).The maximum exploitation of solar energy can be achieved through the optimization of a photo-voltaic thermal (PVT) system. In the PVT system, the (PV) module is cooled down by a water-based thermal collector, and as a result, electricity and hot water are produced. A novel zero-dimensional model is proposed to assess and optimize the performance of such a PVT system. The zero-dimensional model does not rely on spatial resolution or time-dependent variables. The model consists of thermodynamic relations that analyze the energy and the exergy of the PVT system. The validation of the model is performed by comparing its prediction parameters to the parameters collected experimentally from an in-house PVT system. The in-house PVT system consists of a polycrystalline PV module attached to a double series-parallel serpentine thermal collector. The zero-dimensional model predicts the difference between inlet and outlet water temperature as well as the PV surface temperature with an average error of 0.13 °C and 1.80 °C, respectively. Using the zero-dimensional model, the optimization of the PVT performance is achieved by choosing the optimal mass flow rate and inlet temperature for the system. For the experimental setup, a mass flow rate of 0.001 kg/s and an inlet temperature close to a relatively low ambient temperature provided the highest overall second law efficiency of 15.2%. The PVT system performs the best in regions with relatively low ambient temperature yet high solar radiation.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Design and Analysis of Gas Diffusion Layers in a Proton Exchange Membrane Fuel Cell
No full textA proton exchange membrane fuel cell is an energy convertor that produces environmentally friendly electrical energy by oxidation of hydrogen, with water and heat being byproducts. This study investigates the gas diffusion layer (GDL) of the membrane electrode assembly (MEA) in proton exchange membrane fuel cells (PEMFCs). In this regard, the key design concerns and restraints of the GDL have been assessed, accompanied by an inclusive evaluation of the presently existing models. In addition, the common materials used for the GDL have been explored, evaluating their properties. Moreover, a case study of step-by-step modeling for an optimal GDL has been presented. An experimental test has been carried out on a single cell under various compressions. Lastly, a parametric study has been performed considering many design parameters, such as porosity, permeability, geometrical sizes, and compression of the GDL to improve the overall efficiency of the fuel cell. The results are presented in this paper in order to help ongoing efforts to improve the efficiency of PEMFCs and facilitate their development further.American University of Sharja
Multi-Sensor Integrated Navigation System for Ground Vehicle Operations
No full textA Master of Science thesis in Mechatronics Engineering by Nidal A. Sherif entitled, “Multi-Sensor Integrated Navigation System for Ground Vehicle Operations”, submitted in June 2022. Thesis advisor is Dr. Mohammad Jaradat and thesis co-advisor is Dr. Mamoun Abdel-Hafez. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR
Structural Hole Theory, Audit Committee Member Gender, and Financial Restatements
No full textA Master of Science thesis in Finance by Farah Ghazi Radaideh entitled, “Structural Hole Theory, Audit Committee Member Gender, and Financial Restatements”, submitted in August 2022. Thesis advisor is Dr. Kimberly Catherine Gleason. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).Audit committees ensure the independence of auditors from a firm’s management in order to minimize principal-agent conflict. The strength and independence of an audit committee is important for the effectiveness of corporate governance. Audit committees provide oversight of financial reporting, internal control, the audit process, and compliance and it is their responsibility to create an open and trusting environment for transparent discussions between external auditors and management. Research indicates that financial restatements are costly for the company. It is found that restatements increase the cost of equity capital and debt financing for the restating firm (Park & Wu, 2009). Also, financial restatements can affect the future earnings of the firm negatively (Hribar & Jenkins, 2004) and increase information risk (Kravet & Shevlin, 2009). Given that restatements imply failures in financial reporting, the implication of these tends to be worse if initiated externally, as opposed to the firm’s management. Female representation on audit committees, and female audit committee chairs, have been demonstrated to lower audit fees. This has been seen as a result of females’ better communication skills, which in turn reduces the perception of audit risk by external auditors, their enhancement of the integrity of the financial reporting process, and more efficient and effective internal monitoring (Ittonen, Miettinen & Vahamaa, 2010). At the same time, the strength of a director’s connections or social networks, known as “connectedness”, can be linked to the efficiency of running the firm. Board connectedness has also been shown to decrease the cost of debt for companies. Research has shown that financial reporting quality is better if the board members are more connected (Park & Wu, 2009). Structural hole theory argues that highly connected people with strong social ties, known as “social brokers”, are especially valuable due to their increased social capital. Therefore, I argue that it is not only the gender of the audit committee members that affects the probability of restatements, but also the social capital of these members. Given the prior research related to gender and connectedness, and the theoretical link to restatements provided by structural hole theory, I focus on how “connected” women on audit committees affect the probability of financial restatements.School of Business AdministrationDepartment of FinanceMaster of Science in Finance (MSF
Optimal Management of Seasonal Pumped Hydro Storage in UAE
No full textA Master of Science thesis in Electrical Engineering by Asmaa Ibrahim Abdelfattah entitled, “Optimal Management of Seasonal Pumped Hydro Storage in UAE”, submitted in November 2022. Thesis advisor is Dr. Ahmed Osman and thesis co-advisor is Dr. Mostafa Shaaban. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Power demand varies with the time of day and with seasons. Responding to changing demand over time, especially during peak times, is challenging for Energy suppliers. UAE annual demand curve is characterized to be high in seasonal variation. This causes peak power plants to operate more in the highest demand seasons, usually summer, increasing the cost of electricity and the operation of expensive power plants. Peak load shaving is making the load curve flatten by reducing the peak load and shifting it to times of lower demand and hence reduce the operation of expensive power plants. Possible solutions for demand curve flattening are switching off equipment or load-shifting techniques through demand side management (DSM), also through electrical vehicles (EV) integration, and Energy Storage Systems (ESS). However, DSM and EV integration are not applicable solutions for seasonal variation as the peak is mainly driven by the Air conditioning loads. Hence, there is a need for large-scale and long-term ESS to store energy in the time of low-demand seasons for future utilization in the highest-demand ones. This research aims to develop an Energy Management System (EMS) that optimally manages a grid-connected pumped hydro storage (PHS) unit to achieve the purpose of peak shaving. The proposed framework analyses the seasonal performance of PHS in supporting the grid in the UAE and reflects the possible economic benefits considering transmission constraints, optimal power flow, hydraulic model, and losses over a study period of one year. The proposed model incorporates dynamic economic dispatch (DED) over a relatively long period; hence DC power flow analysis is considered to ensure fast load flow estimation. This analysis is essential to motivate the construction of new seasonal PHS plants due to the high construction cost they are identified with, especially in geographical areas where this technology is not yet considered and is hard to construct.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
The Building Blocks of Business Contracts’ Recitals: A Corpus-Induced Approach to Assessing Homogeneity
No full textA Master of Arts thesis in Teaching English to Speakers of Other Languages (TESOL) by Reem Kamal Rabea entitled, “The Building Blocks of Business Contracts’ Recitals: A Corpus-Induced Approach to Assessing Homogeneity”, submitted in December 2022. Thesis advisor is Dr. Philip McCarthy. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).By following a bottom-up approach based on principles of induction, the current study aims to provide the most typical lexical units of the provisional element of recitals in business contracts. In doing so, a novel methodological approach to corpus homogeneity is proposed to satisfy quality standards of the corpora serving the purpose of this study. Cosine values were utilized for homogeneity operationalization since they operate on the principle of similarity. Further, in producing the frequency wordlists, the study focuses on two methodological parameters, namely N-gram sequence length and frequency, which are proposed by Biber and Conard (2005). By means of a textual analysis tool named Gramulator (McCarthy et al., 2012), the N-grams common to two specialized corpora of several contract types were extracted. A preliminary frequency baseline (< 50%) was employed in the selection process. More notably, the statistical examination of the data suggests the presence of a parent-child relationship between both corpora. The findings of the current study are of interest to English for legal purposes (ELP) practitioners who are precisely teaching new law students as well as researchers that wish to investigate the discourse functions forming the conventions of business contracts drafting.College of Arts and SciencesDepartment of EnglishMaster of Arts in Teaching English to Speakers of Other Languages (MA TESOL
Gesture-based Graph-theoretic Robot Formation Control
No full textA Master of Science thesis in Mechatronics Engineering by Mahroo Sajid entitled, “Gesture-based Graph-theoretic Robot Formation Control”, submitted in June 2022. Thesis advisor is Dr. Shayok Mukhopadhyay. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Multi-robot systems have many diverse applications including but not limited to surveillance, search and rescue operations, hazardous material handling, agriculture etc. Formation control is a key requirement out of the many facets of robotic swarm control. While the formation control problem has been extensively explored, including vastly different and various approaches; consensus-based formation control has definitive advantages in terms of providing a robust and distributed control algorithm. In the proposed work, the notion of consensus-based control of the formations of a robotic network utilizing bare-handed gestures is explored. While similar examples can be found in recent research endeavors (including selection and command of groups of UAVs, UGVs and under-water robots), most utilize electronic or specialized devices for the purpose of Human-Swarm Interaction (HSI). This is despite the major breakthroughs in the field of image recognition and classification. The proposed gesture-recognition approach is based on an algorithm capable of discerning the finger count (number of open digits) in 2.5 seconds (on average) with 88.75% accuracy thus affording the user a vocabulary of up to five (5) individual commands / directives to assemble and control the robotic swarm. The gesture recognition algorithm was modified to increase the detection accuracy to 90.8%.College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR
AgroAId: A Mobile App System for Visual Classification of Plant Species and Diseases Using Deep Learning and TensorFlow Lite
No full textThis paper aims to assist novice gardeners in identifying plant diseases to circumvent misdiagnosing their plants and to increase general horticultural knowledge for better plant growth. In this paper, we develop a mobile plant care support system (“AgroAId”), which incorporates computer vision technology to classify a plant’s [species–disease] combination from an input plant leaf image, recognizing 39 [species-and-disease] classes. Our method comprises a comparative analysis to maximize our multi-label classification model’s performance and determine the effects of varying the convolutional neural network (CNN) architectures, transfer learning approach, and hyperparameter optimizations. We tested four lightweight, mobile-optimized CNNs – MobileNet, MobileNetV2, NasNetMobile, and EfficientNetB0 – and tested four transfer learning scenarios (percentage of frozen-vs.-retrained base layers): (1) freezing all convolutional layers; (2) freezing 80% of layers; (3) freezing 50% only; and (4) retraining all layers. A total of 32 model variations are built and assessed using standard metrics (accuracy, F1-score, confusion matrices). The most lightweight, highaccuracy model is concluded to be an EfficientNetB0 model using a fully retrained base network with optimized hyperparameters, achieving 99% accuracy and demonstrating the efficacy of the proposed approach; it is integrated into our plant care support system in a TensorFlow Lite format alongside the front-end mobile application and centralized cloud database. Finally, our system also uses the collective user classification data to generate spatiotemporal analytics about regional and seasonal disease trends, making these analytics accessible to all system users to increase awareness of global agricultural trends.American University of Sharja