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INSPECT-PBEE: a performance-based earthquake engineering GUI for IDARC-2D
No full textDesigns that are performance and functionality driven typically mandate the nonlinear analysis. Up To date, nonlinear analysis remains a sophisticated tool that may not appeal to majority of structural/earthquake practicing engineers due to the required effort, time and its iterative nature. There are several available commercial and research-oriented packages that perform nonlinear analyses. IDARC-2D is one of the powerful and freely available tools for nonlinear analyses. This paper presents INSPECT-PBEE which is a software pre/post processor package developed to facilitate the use of IDARC-2D program and automates the seismic performance evaluation of structures. It operates in two modes; a preprocessor and a post-processor, developed using C# programming language and .Net libraries. The preprocessor package simplifies the nonlinear modeling process on IDARC-2D using its useful Graphical User Interface (GUI). The post-processor component provides a powerful tool that automates the seismic performance assessment of structures using inelastic dynamic analyses. Furthermore, it has two options for evaluating the seismic performance, either user-specified criteria or following the well-established procedure described in the FEMA P695 document
Gut bacteria of Cuora amboinensis (turtle) produce broad-spectrum antibacterial molecules
No full textAntimicrobial resistance is a major threat to human health, hence there is an urgent need to discover antibacterial molecule(s). Previously, we hypothesized that microbial gut flora of animals are a potential source of antibacterial molecules. Among various animals, Cuora amboinensis (turtle) represents an important reptile species living in diverse ecological environments and feed on organic waste and terrestrial organisms and have been used in folk medicine. The purpose of this study was to mine turtle’s gut bacteria for potential antibacterial molecule(s). Several bacteria were isolated from the turtle gut and their conditioned media were prepared. Conditioned media showed potent antibacterial activity against several Gram-positive (Bacillus cereus, Streptococcus pyogenes and methicillin-resistant Staphylococcus aureus) and Gram-negative (neuropathogenic Escherichia coli K1, Serratia marcescens, Pseudomonas aeruginosa, Salmonella enterica and Klebsiella pneumoniae) pathogenic bacteria. Conditioned media-mediated bactericidal activity was heat-resistant when treated at 95°C for 10 min. By measuring Lactate dehydrogenase release, the results showed that conditioned media had no effect on human cell viability. Tandem Mass Spectrometric analysis revealed the presence of various secondary metabolites, i.e., a series of known as well as novel N-acyl-homoserine lactones, several homologues of 4-hydroxy-2-alkylquinolines, and rhamnolipids, which are the signature metabolites of Pseudomonas species. These findings are significant and provide the basis for rational development of therapeutic interventions against bacterial infections
Solution of Fractional Differential Equations: Variational Iteration Approach
No full textA Master of Science thesis in Mathematics by Reem Amer Assadi entitled, “Solution of Fractional Differential Equations: Variational Iteration Approachs”, submitted in December 2019. Thesis advisor is Dr. Suheil Khoury. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).This thesis discusses a newly introduced numerical scheme for fractional differential equations. The strategy is an extension of the Variational Iteration Method (VIM) and is suitable for boundary value problems (BVPs). The presented Generalized Variational Iteration Method (GVIM) is particularly used for tackling BVPs. The scheme yields accurate solutions for which the errors are uniformly distributed across the domain. The numerical results confirm that this approach is reliable, and has a high convergence rate compared to other existing methods.College of Arts and SciencesDepartment of Mathematics and StatisticsMaster of Science in Mathematics (MSMTH
On Morpho-Syntactic Levantisms in Maltese
No full textMaltese is usually classified as a North African Arabic variety. Yet some researchers have remarked “some curious similarities with the Eastern dialects”. Investigations of these tend to concentrate upon the phonology and lexicon, with slight attention paid to morphology and syntax. We report on a long-term project in documenting some of those, including polar interrogation with a reflex of /š/; the prohibitive/dehortative system, also exhibiting reflexes of /š/; double object marking with reflexes of /l-/; and pronominal circumstantial clauses. None of these is excusive to Maltese and the Levant alone. Polar interrogation with /š/ is found in the Levantine, and North African, and Andalusi Arabic. The Maltese prohibitive is largely southern Levantine in form, but its dehortative is common to eastern Mediterranean dialects of Arabic. Double object marking with reflexes of /l-/ appears in Andalusi, Levantine, and Mesopotamian varieties. The Maltese pronominal circumstantial clause is similar to Syro-Lebanese Arabic, the Beʿēri Arabic of Upper Egypt, and some dialects of the United Arabic Emirates
Durability of Mortar and Epoxy Bonded Galvanized Steel Mesh Sheets to Concrete Surfaces
No full textA Master of Science thesis in Civil Engineering by Kais Aiman Douier entitled, “Durability of Mortar and Epoxy Bonded Galvanized Steel Mesh Sheets to Concrete Surfaces”, submitted in April 2019. Thesis advisor is Dr. Rami Haweeleh and thesis co-advisor is Dr. Jamal Abdalla. Soft and hard copy available.Over the last few decades, fiber-reinforced polymer (FRP) sheets and plates have been extensively used as external strengthening materials and proved to be quite effective in enhancing the flexure and shear strength of reinforced concrete (RC) beams. Recently, galvanized steel mesh (GSM) composite sheets have emerged as a promising strengthening material due to its desirable mechanical properties and light-weight. However, very limited studies have been conducted to investigate the durability of bond behavior of GSM sheets to concrete surfaces, especially when subjected to harsh environments. Therefore, the main aim of this study is to investigate the bond behavior of GSM sheets attached externally to concrete surfaces via epoxy adhesive (SME) or cement-based mortar (SMM). Both systems were subjected to sun light and saline water exposures for up to a 12 months period. This study will examine the degradation of flexural and bond strength in RC beams, flexural bond prisms, mechanical properties of coupon laminates, and single-lap shear pullout specimens strengthened with both systems. The test results showed that RC beams strengthened with SME laminates achieved an initial increase of 55% in its load carrying capacity and retained 99 and 95% of its strength after 360 days of saline water and sun light exposures, respectively. However, RC beams strengthened with SMM laminates achieved an initial increase of 50% in its load carrying capacity and retained 71 and 74% of its strength after 360 days of exposure in saline water and sun light, respectively. Thus, it could be concluded that SME strengthening system is the best strengthening system that experienced the least degradation in both exposures when compared with SMM strengthening systems. The outcomes from this research will aid in developing environmental factors (CE) for each exposure and test method that could be used in the design and analysis of externally bonded RC beams in the UAE and countries with similar harsh environmental exposures.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
What We Have Learned about Terrorism since 9/11
No full textThis overview examines critically the post-9/11 empirical literature on terrorism. Major contributions by both economists and political scientists are included. We focus on five main themes: the changing nature of terrorism, the organization of terrorist groups, the effectiveness of counterterrorism policies, modern drivers or causes of terrorism, and the economic consequences of terrorism. In so doing, we investigate a host of questions that include: How do terrorist groups attract and retain members? What determines the survival of terrorist groups? Is poverty a root cause of terrorism? What counterterrorism measures work best? In the latter regard, we find that many counterterrorism policies have unintended negative consequences owing to attack transference and terrorist backlash. This suggests the need for novel policies such as service provision to counter some terrorist groups' efforts to provide such services. Despite terrorists' concerted efforts to damage targeted countries' economies, the empirical literature shows that terrorism has had little or no effect on economic growth or GDP except in small terrorism-plagued countries. At the sectoral level, terrorism can adversely affect tourism and foreign direct investment, but these effects are rather transient and create transference of activities to other sectors, thus cushioning the consequences
Millimeter Wave Channel Characterization for 5G Cellular Systems in the UAE at the 28 GHz Band
No full textA Master of Science thesis in Electrical Engineering by Mohammed K.Y. Aborahama entitled, “Millimeter Wave Channel Characterization for 5G Cellular Systems in the UAE at the 28 GHz Band”, submitted in May 2019. Thesis advisor is Dr. Amer S. Zakaria and thesis co-advisors Dr. Mahmoud H. Ismail Ibrahim and Dr. Mohamed El-Tarhuni. Soft and hard copy available.The rapid increase in wireless communication services and the need for higher data rate communications have pushed people towards adopting fifth generation (5G) cellular systems. One of the new technologies to be used in 5G is using the millimeter wave (mm-wave) band for the carrier signals. Though mm-waves are expected to cover the needed bandwidth and data rate, they suffer from higher losses and scattering from more objects within the radio channel than the currently used frequencies. For this reason, the effect of the channel should be studied well before implementing 5G technology to be able to design 5G systems and know their capabilities. This is done by conducting large-scale, small-scale, penetration loss and reflectivity channel measurements. Many measurements have been conducted for mm-wave channel characteristics in different parts of the world. However, no measurements have been reported in environments similar to that in the UAE. Thus, in this work, large-scale, small-scale and penetration loss measurements were conducted in the UAE; the study covers many aspects of wireless channel characteristics. The measurements were conducted from April 2018 until April 2019 in the American University of Sharjah’s campus. A narrow-band wireless communication setup and a wideband wireless setup have been assembled. Path loss measurements were conducted in labs, corridors, building rotunda, halls and outdoor areas using 28 GHz band. The measurements revealed that the path loss exponent is mostly around that would be observed in a free space model and that is aligned with measurements reported in the literature. In addition to that, penetration and reflection measurements were conducted for building material used in the UAE. Finally, wideband channel impulse response measurements were conducted in the 24 GHz band with a signal bandwidth of 250 MHz. The power delay profile and channel delay spread results show that the maximum RMS delay spread observed was about 247 ns and 433 ns for indoor and outdoor environments, respectively.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
WMS, APIs and LibGuides: Building a Better A-Z List
No full textPresentation about developing a database A-Z list using WorldShare Management Services (WMS) and LibGuides. Presented at the 1st EMEA WMS Users Group meeting in Edinburgh, Scotland on February 22, 2018
Design of a Fully Concentrated Solar Powered Electricity Generation Plant for the UAE
No full textA Master of Science thesis in Mechanical Engineering by Hessa Abbas Ali entitled, “Design of a Fully Concentrated Solar Powered Electricity Generation Plant for the UAE”, submitted in September 2018. Thesis advisor is Dr. Mohamed Gadalla. Soft and hard copy available.The increase in the world’s demand for electricity and the depletion of the fossil fuels used in conventional power plant systems raises the need for different renewable sources of electricity generation. Concentrated solar panel (CSP) is a leading solar technology, with parabolic trough (PT) collectors being the most efficient and advanced type of CSP. This thesis aims to propose and analyze a viable 50 MWe output CSP-PT plant to be integrated into the grid system of the United Arab Emirates (UAE). The simulation and analysis is performed using the System Advisor Model (SAM) and EnergyPLAN software. SAM is used to model the design of the plant and obtain the profiles of the energy supply throughout the year, which is fed to EnergyPLAN. The designed plant includes a thermal energy storage (TES) system to ensure 24-hour daily electricity generation with a 10-hour generation from direct solar energy and 14-hour generation through the use of energy stored in the TES. Three heat transfer fluids (HTFs) – molten salt, water and Therminol VP-1 – are also compared through modeling two configurations and the most efficient combination is selected. The result of this study is a feasible solar 50 MWe power generation plant that operates 24-hours per day by utilizing a 2 x 8 panel CSP-PT field, each panel being 12 m x 12 m, a two-tank direct TES, each tank being 6,604 m³ in volume, with molten salt as the HTF and storage fluid, running a Rankine cycle power block with an open feed water heater. Economic analysis of the model is presented and evaluated in detail, using EnergyPLAN. The internal rate of return (IRR) at the end of the project is found to be 21.40%, which is within the typical IRR limits (16-25%), and the project’s minimum debt service coverage ratio (DSCR) is 1.42, which is much higher than the least expected minimum value of 1.3. The levelized cost of electricity (LCOE) is 15.60 cents/kWh and the payback period on the monetary investment of this plant is 17.3 years. This study proves the feasibility of the realization of a fully solar-powered electricity plant.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Soil remediation from waste lubricating oil
No full textSoil remediation was investigated from waste oil contamination. Contamination of different soil particle diameters was prepared with different dosage of waste oil contamination. Solvent extraction technique was employed for remediation using batch process. The contaminated soil was treated with many solvents and different solvents to oil ratios. The solvent was recovered and reused. The soil and waste oil were analyzed before and after remediation process to study the performance of soil remediation process. A mathematical model for remediation process was constructed. The performance of different solvents for soil remediation is as follow:
LPG Condensate - Dichloromethane - Trichloromethane - MEK - Stabilized Condensate - Hexane - Heptane - 1-butanol - toluene - ethyl acetate - 2-propanol. Physical properties of recovered waste oil showed lower carbon residue, ash content, and asphaltene content due to the adsorption of heavy molecular weight hydrocarbons inside the pores of the soil after extraction process. The treated soil may need further regeneration process to recover it from the entire heavy molecules. Two stages extraction process was performed to remove all the heavy constituents from the pores of the contaminated soil