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Prize-Linked Savings Games: Theory and Experiment
No full textWe introduce a game in which each player can allocate her endowment in a prize-linked savings (PLS) account, which awards a fixed prize only to a randomly chosen winner. Like Tullock's rent-seeking contest, the probability for each player of winning the prize is the ratio of her PLS deposit to the total deposits made by all participating players. We derive a unique equilibrium and further examine the effects of introducing PLS as an alternative savings option to traditional savings (TS), which yields a fixed rate of return. Our theory predicts that, while inducing the group with low TS deposits to save more, PLS will cannibalize TS and reduce total savings in the group with high TS deposits. However, in contrast to the theory, our experimental results show that PLS significantly increases total savings in both groups
Forecasting Energy Demand: The Case of United Arab Emirates
No full textThe purpose of this study is to forecast energy use in United Arab Emirates (UAE) using annual data over the period 1976-2009. The methodology used in this study follows the artificial neural networks analyses. We use four independent variables, namely, gross domestic product, population, exports, and imports to forecast energy use. Empirical results reveal that the projected energy use in United Arab Emirates will reach 69,000 and 76,900 Kt. of oil equivalent in years 2015 and 2020, respectively. Thus, a better and more realistic energy forecast is necessary for the policy makers when making decisions for the next decade. Therefore, the policy makers need to take this increase in energy use into consideration as it may pose a threat to economic development in the country should energy needs will not be met
WMS, APIs and LibGuides: Building a Better Database A-Z List
No full textAt the American University of Sharjah, our Databases by title and by subject pages are the 3rd and 4th most visited pages on our website. When we changed our ILS from Millennium to OCLC’s WorldShare Management Services (WMS), our previous automations which kept our Databases A-Z pages up-to-date were no longer usable and needed to be replaced. Using APIs, a Perl script, and LibGuides’ database management interface, we developed a workflow that pulls database metadata from WMS Collection Manager into a clean public-facing A-Z list. This article will discuss the details of how this process works, the advantages it provides, and the continuing issues we are facing
Stop-Go Monetary Policy
No full textWe propose and estimate several discrete choice models of monetary policy decision-making that feature time-varying inertia. The models permit us to account for three stylized facts characterizing monetary policy making in the United States: (1) target interest rates are gradually adjusted in small discrete movements, (2) there are some long stretches of time in which rate are repeatedly moved, and (3) there are other long stretches of time in which the policy rate does not change. The proposed models perform well in predicting in-sample policy choices of the Federal Reserve and can explain the presence of policy inertia without including multiple lagged dependent variables in a monetary policy reaction function
Mobile Robot Navigation in Dynamic Environments Using an Improved RRT* Approach
No full textA Master of Science thesis in Mechatronics Engineering by Hussein Ali Mohammed entitled, “Mobile Robot Navigation in Dynamic Environments Using an Improved RRT* Approach”, submitted in November 2018. Thesis advisor is Dr. Lotfi Romdhane and thesis co-advisor is Dr. Mohammad Jaradat. Soft and hard copy available.A very prominent area in the field of Mechatronics is robot navigation and path planning. This area deals with the problem of autonomously calculating the least cost path in a provided environment, whether it is static or dynamic, and navigating the robot platform though this environment. Over the last decade, since the year 2001, there have been major breakthroughs in this field after LaValle introduced his revolutionary algorithm, the Rapidly-Exploring Random Tree (RRT) approach. Later, in the year 2011, Karaman introduced his novel modification to RRT which he called the Rapidly- Exploring Random Tree Star (RRT*). The main advantage of RRT* is its effectiveness and robustness in finding the path to the target and its probabilistic completeness property which guarantees the best theoretical path if given enough run time. However, RRT* still suffers from long processing times to provide paths with satisfactory quality in terms of cost and smoothness. Having said that, in this thesis we propose an improved version of the RRT* algorithm which will address the issue of long processing times and sub-par path quality. This new method is called Rapidly-Exploring Random Tree Star Normal (RRT*N). The presented method can handle static and dynamic obstacles in 2D and 3D environments. This improved method uses a Gaussian probability distribution to generate new nodes which have a higher probability of being generated along the vector pointing from the starting point to the goal point, which results in a tree centered on the line joining the robot to the target. It is shown that this method can be three times faster in finding the path to the target in static scenarios, and upto 20 times faster in dynamic environments compared to RRT*. Furthermore its rate of achieving satisfactory paths is consistently more than 95% while maintaining similar path quality. For instance in 250 trials of the presented static scenario, RRT*N had an average processing time and average path length of 38.46 seconds and 240.99 units, respectively. Meanwhile, RRT* resulted in 121.58 seconds and 259.11 units. This work is based on an extensive literature review to validate this work’s novelty and the simulation and experimental results presented show the robustness of the proposed RRT*N method.College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR
5G User Equipment Phased Array Antenna Architecture for Millimeter Wave Beamforming Applications
No full textA Master of Science thesis in Electrical Engineering by Eiman Ayman Mahmoud ElGhanam entitled, “5G User Equipment Phased Array Antenna Architecture for Millimeter Wave Beamforming Applications”, submitted in December 2018. Thesis advisor is Dr. Lutfi Albasha and thesis co-advisors are Dr. Nasser Qaddoumi and Dr. Hassan Mir. Soft and hard copy available.With the increase in demand for higher capacities and enhanced coverage, extensive research is conducted towards addressing this demand through the upcoming fifth generation of mobile networks, also known as 5G. In order to achieve the desired coverage enhancement, beamforming techniques are gaining increasing momentum in the cellular industry, particularly with the interest in utilizing millimetre waves as new cellular spectrum bands with wide bandwidths. Different beamforming architectures are currently being investigated to provide optimized performance in terms of gain, beam-steerability and hence, improved coverage. This thesis proposes a novel, small-sized, low-cost continuous phase shifter-based phased array antenna architecture to be integrated into the frontend module of a user equipment to perform high efficiency RF beamforming at certain 5G-candidate millimeter wave frequency bands, particularly 18 GHz, 26 GHz and 28 GHz. The proposed architecture is designed such that it utilizes less than N phase shifters to drive N antenna elements while achieving high linearity and reduced power consumption. The topology is simulated on Keysight ADS Software and is optimized to achieve 50 Ω characteristic impedance matching, wideband behavior and optimal spacing to fit into a 5G user equipment. Nevertheless, due to the large microstrip losses at millimeter waves, the proposed architecture exhibits suboptimal behavior for the insertion loss and the achievable phase shift range. Despite partially meeting the design specifications, the obtained results provide a proof of concept of the ability to use the proposed architecture in millimeter wave beamforming for 5G user equipment.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
Minimizing Traffic Congestion through V2V Communication
No full textA Master of Science thesis in Engineering Systems Management by Suhieb Alqawasmeh entitled, “Minimizing Traffic Congestion through V2V Communication”, submitted in January 2018. Thesis advisor is Dr. Noha Mohamed Hassan Hussein and thesis co-advisor is Dr. Malick Ndiaye. Soft and hard copy available.With the rising level of vehicular traffic congestion, it is important to find a way to manage these congestions at an early stage. Connected vehicle technology is a potential solution that can significantly improve traffic system efficiency. Cars use short range radio signals to communicate with each other, so that they are aware of other vehicles’ position in roads. Drivers can, subsequently, receive notifications and alert others of dangerous situations in the road ahead. A heuristic approach was developed in this research to design a dissemination strategy based on a dynamic set covering model that ensures full coverage with the minimum number of relay vehicles. This model selects the optimal relay vehicles at each dissemination step, which in turn will communicate the information to other vehicles. The selection of the optimal relay vehicles was solved by formulating a linear programming model that minimizes the number of the selected relay vehicles while maintain full coverage for all vehicles. The model was tested and coded using the Matlab software simulating a highway and an urban environment configuration. Model validation and evaluation were carried for both configurations. A comparison was performed with other proposed models included in the literature review. The proposed model showed a significant decrease in the dissemination time of a warning message. The longest time recorded was 1.4 seconds for a road length of 1 km with vehicle density of 0.125 vehicle per lane per meter in a highway scenario with a number of transmitted messages of 353741. In the urban scenario of two 1 km roads and vehicle density of 0.125 the model recorded a time of 0.8 seconds with 481562 messages disseminated. A better performance in terms of delay time was achieved for the proposed model compared to any of the other models studied. This short delay time gives a better opportunity for the drivers to take an alternative route in case of congestions. The increase in road lengths does not need to increase the number of relay vehicles significantly, which shows the efficiency of the proposed model.College of EngineeringDepartment of Industrial EngineeringMaster of Science in Engineering Systems Management (MSESM
Green Nanotechnology—A Road Map to Safer Nanomaterials
No full textNanotechnology has remained at the forefront of scientific research for the past few decades due to its outstanding properties and associated applications. The unlimited potential of nanomaterials have already influenced human life immensely. However, possible harmful impacts of nanomaterials on human health and the environment have always remained a ‘fear factor.’ Extensive research on the toxicity and complexity of nanomaterials has paved the way toward the development of nanotoxicology, which analyzes the root causes of these issues. Nevertheless, the implementation of safer guidelines was needed to ensure that nanomaterials are safe for both human health and the environment. Green chemistry principles were introduced to develop safer methods to produce and handle nanomaterials, leading to the new field of green nanotechnology. This chapter discusses the principles, biomedical applications, limitations, and future prospects of green nanotechnology
A General Framework for Sustainability Assessment of Manufacturing Processes
No full textA Master of Science thesis in Mechanical Engineering by Mohammed Hassoun Saad entitled, “A General Framework for Sustainability Assessment of Manufacturing Processes”, submitted in November 2018. Thesis advisor is Dr. Basil Darras and thesis co-advisor is Dr. Mohammad Nazzal. Soft and hard copy available.The manufacturing sector has a major impact on the three sustainability dimensions represented by social, economic, and environmental aspects. Most of the work on sustainability assessment in the field of manufacturing is conducted at the product level or for specific processes; mainly machining with a limited number of indicators that do not capture all three dimensions of sustainability. The aim of this work is to develop a new systematic and comprehensive framework for the sustainability assessment of manufacturing processes that covers the three sustainability dimensions. Guidelines to select and quantify the relevant indicators, convert the quantified weighted indicators into dimensionless quantities, and rank the alternatives based on the aggregated scores are presented. The proposed framework combines objective and subjective weighting methods to reduce the uncertainty associated with subjective weighting. It also captures the interaction among different indicators by utilizing multi-criteria decision making methods instead of the traditional statistical methods. Sensitivity analysis is proposed to ensure the reliability and robustness of the aggregated results (final scores). A case study is carried out by applying the proposed framework to evaluate the sustainability level of four welding processes, which are Friction Stir Welding (FSW), Gas Metal Arc Welding (GMAW), Gas Tungsten Arc Welding (GTAW) and Shielded Metal Arc Welding (SMAW). The four processes are used to weld aluminum 5083 plates with a thickness of 5 mm. Physical performance of the welded plates is considered as a fourth sustainability dimension to assess the quality of the welded parts. The assessment is carried out using three multi-criteria decision making methods, which are the TOPSIS, GRA and COPRAS. The results obtained from the assessment reflect that the FSW welding is the most sustainable welding process for this case with an overall sustainability score of 0.611 based on TOPSIS method, 0.753 based on GRA, and 0.317 based on the COPRAS method.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Forecasting model to predict project success based on the contractors’ characteristics
No full textA Master of Science thesis in Engineering Systems Management by Khalid Waleed Rashid Deemas AlSuwaidi entitled, “Forecasting Model to Predict Project Success Based on the Contractors’ Characteristics”, submitted in April 2018. Thesis advisor is Dr. Sameh El-Sayegh. Soft and hard copy availableSuccessful delivery of construction projects requires completing the projects on time and within budget, while ensuring the delivery of a quality product. Most construction projects experience delays, cost overruns and quality problems. In a country like the United Arab Emirates (UAE), where high development activities are happening rapidly, it is very dangerous for the overall economy if repeated failures in construction projects remain unsolved or even uninvestigated. The selection of the right contractor has a direct and significant impact on the success of construction projects. There is a need to select the appropriate contractor who is capable of increasing the chances of the project’s success. Relying on the selection of the lowest bidder is misleading. The research objective is to develop a model that predicts the project’s success based on the contractor’s characteristics, be they financial or non-financial. This will reduce the risks associated with the process extensively. Sixteen key characteristics, that have a direct impact on project success, were identified through an extensive literature review. Those sixteen characteristics were grouped into four main categories: the firm’s capacity, past experience and past performance, project management capabilities and sustainability and technology practices. A survey, using the Analytic Hierarchy Process (AHP), was conducted to prioritize those characteristics and link them to the success criteria. Success criteria were limited to cost, time and quality. Forty-five respondents completed the survey including owners, contractors and consultants. The results indicated that respondents prefer financial (bid price) slightly over non-financial characteristics (0.513 and 0.487, respectively). As for the non-financial characteristics, the results show that the main categories are ranked as follows: project management capabilities, past experience and past performance, sustainability and technology practices and firm’s capacity. Four out of the top five characteristics were found to be part of the project management capabilities group. In terms of project success criteria, the results are as follows: quality (0.413), cost (0.317), and time (0.270). Through relating contractor characteristics and financial factors to the project success criteria, a forecasting model has been developed to predict project success based on the given parameters. A case study is also presented to show the application of the proposed model.College of EngineeringDepartment of Industrial EngineeringMaster of Science in Engineering Systems Management (MSESM