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Drone Based Outdoor Insulator Inspection
No full textA Master of Science thesis in Mechatronics Engineering by Danial Waleed entitled, “Drone Based Outdoor Insulator Inspection”, submitted in April 2019. Thesis advisor is Dr. Shayok Mukhopadhyay and thesis co-advisor Dr. Usman Tariq. Soft and hard copy available.Over the past few decades, interest in unmanned aerial vehicles (UAVs) and in particular quadcopters has increased due to the wide range of possible research applications that can benefit from the use of quadcopters. Insulator inspection on overhead power lines has traditionally relied heavily on visual inspection. The task is both cumbersome and relies on the experience of the inspector. It is also extremely dangerous as the inspector needs to work in close proximity with overhead power lines, and contact with these lines can lead to instant death. This thesis focuses on the development of a quadcopter based system that is able to inspect insulators on overhead power lines. The proposed system consists of a quadcopter that is able to inspect the health of insulators on an overhead power line. The quadcopter, via the help of its onboard cameras and Raspberry Pi based computer, is able to detect the health of an overhead power line insulator and simultaneously send images to the ground station where they are processed. The main contribution of this thesis is the development of a complete quadcopter based system for overhead power line insulator inspection. The offshore image processing algorithm presented in this thesis has a mean average precision of 0.66 and an average processing time of 0.55 seconds. The onboard image processing algorithm has a mean average precision of 0.26 and an average processing time of 1.28 seconds. These numbers show that quadcopter based insulator inspection can be carried out successfully using both offshore and onboard image processing techniques both in terms of precision and image processing time.College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR
Recent Advances in Femtosecond Laser-Induced Surface Structuring for Oil–Water Separation
No full textFemtosecond (FS) laser-induced surface structuring is a robust, maskless, non-contact, and single-step process for producing micro- and nanoscale structures on a material’s surface, which remarkably alters the optical, chemical, wetting, and tribological properties of that material. Wettability control, in particular, is of high significance in various applications, including self-cleaning, anti-fouling, anti-icing, anti-corrosion, and, recently, oil–water separation. Due to growing energy demands and rapid industrialization, oil spill accidents and organic industrial discharges frequently take place. This poses an imminent threat to the environment and has adverse effects on the economy and the ecosystem. Oil–water separation and oil waste management require mechanically robust, durable, low-cost, and highly efficient oil–water manipulation systems. To address this challenge superhydrophobic–superoleophilic and superhydrophilic–underwater superoleophobic membrane filters have shown promising results. However, the recyclability and durability issues of such filters are limiting factors in their industrial application, as well as in their use in oil spill accidents. In this article, we review and discuss the recent progress in the application of FS laser surface structuring in producing durable and robust oil–water separation membrane filters. The wide variety of surface structures produced by FS laser nano- and micromachining are initially presented here, while the excellent wetting characteristics shown by specific femtosecond-induced structures are demonstrated. Subsequently, the working principles of oil–water separation membranes are elaborated, and the most recent advances in the topic are analyzed and discussed
BIM as a Pedagogical Tool for Teaching HVAC Systems to Architecture Students
No full textUnderstanding the basics of Environmental Control Systems including HVAC systems is required in architectural curricula. One of the challenges of learning this subject is the nonfamiliarity of the students with the components of these systems and how the selection and installation of these components can impact the architecture of the building and its spacial experience. Such difficult interrelationships can be clarified using various techniques. One technique that the author experimented with is the use of a BIM tool. Yet, using the tool to achieve this purpose had been a challenge in itself. The tool needs to be setup and its interface needs to be configured for a particular learning objective within a defined learning environment. This paper discusses the various techniques to achieving the learning of this required subject. It also shares the details of preparing and executing the experiment of using BIM hoping that other instructors make use of it and further build on it. A survey of the students who went through the experiment shows that a large majority believes that they learned the subject better through the BIM tool
Gut Bacteria of Water Monitor Lizard (Varanus salvator) Are a Potential Source of Antibacterial Compound(s)
No full textFor the past few decades, there has been limited progress in the development of novel antibacterials. Previously, we postulated that the gut microbiota of animals residing in polluted environments are a forthcoming supply of antibacterials. Among various species, the water monitor lizard is an interesting species that feeds on organic waste and the carcass of wild animals. Gut microbiota of the water monitor lizard were sequestered, identified and cultivated in RPMI-1640 to produce conditioned medium (CM). Next, the antimicrobial properties of CM were evaluated versus a selection of Gram-negative (Escherichia coli K1, Serratia marcescens, Pseudomonas aeruginosa, Salmonella enterica and Klebsiella pneumoniae) and Gram-positive bacteria (Streptococcus pyogenes, methicillin-resistant Staphylococcus aureus, and Bacillus cereus). CM were partially characterized by heat inactivation at 95°C for 10 min and tested against P. aeruginosa and S. pyogenes. CM were also tested against immortalized human keratinocytes (HaCaT) cells lines. The results demonstrated that gut microbiota isolated from water monitor lizard produced molecules with remarkable bactericidal activities. To determine the identity of the active molecules, CM were subjected to Liquid Chromatography-Mass Spectrometry. Several molecules were identified belonging to the classes of flavonoids, terpenoids, alkaloids, polyhydroxy alkaloids, polyacetylenes, bisphenols, amides, oxylipin and pyrazine derivatives with known broad-spectrum antimicrobial, anti-tumour, anti-oxidant, anti-inflammatory, and analgesic attributes. Furthermore, the detailed analysis of these molecules could lead us to develop effective therapeutic antibacterials
Real-Time Path-Planning using Depth/INS Sensor Fusion for Localization
No full textA Master of Science thesis in Mechatronics Engineering by Fares Amin E Alkhawja entitled, “Real-Time Path-Planning using Depth/INS Sensor Fusion for Localization”, submitted in December 2019. Thesis advisor is Dr. Lotfi Romdhane and thesis co-advisor is Dr. Mohammad Jaradat. Soft copy is available (Thesis, Approval Signatures, Completion Certificate, and AUS Archives Consent Form).This thesis discusses a hardware implementation of a navigating robot that plans its path and localizes itself in indoor and outdoor environments. It aims to enhance the process of navigation by enhancing the localization module of it. After feeding the cost-map along with the obstacles, path-planning algorithm (A*) chooses the lowest cost until it reaches the destination. The path planning controller uses the dynamic state of the robot using different localization techniques for outdoor and indoor environments. The objective is to make the localization process more stable to improve the navigation. The enhanced localization technique uses the depth camera localization data in indoor environments and outdoor environments, to enhance the results obtained by the IMU raw data through a depth-inertial fusion. The fusion algorithm is based on feed-forward cascade correlation network, which is part of the neural networks and it is assessed using different sensors and different neural networks methods. The robot uses the localization data in addition to the planned path to control its movement towards the destination. Results section shows the enhancement that was made to the localization process compared to the IMU localization or the depth camera localization through using the mentioned fusion algorithm.College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR
The Roots of Misalignment: Insights on Strategy Implementation from a System Dynamics Perspective
No full textThis essay advances the study of strategic alignment by explaining how and why misalignment occurs. We begin by summarizing why IT and business strategies evolve in unintended ways, a phenomenon known as strategic drift. Using the causal loop diagramming approach of system dynamics, we observe that several sources of drift, potentially resulting in misalignment, are paradoxically built into the process of strategy formation and enactment itself. These linked subprocesses involve multiple actors at multiple levels of an organization and operate to promote (or hinder) strategic alignment. This paper contributes to the literature by enumerating and modeling both the top-down processes that can promote (or hinder) strategic alignment, as well as the less-studied bottom-up processes, ultimately yielding a more nuanced, dynamic, process-oriented understanding of strategic alignment. Directions for future research include the study of alignment at the process and group levels, as well as an exploration of settings where certain types of strategic drift and misalignment yield beneficial outcomes
Experimental Analysis of High Temperature Shape Memory Polymers for Deployable Structures
No full textA Master of Science thesis in Mechanical Engineering by Mohamad Youssef ElMaoud entitled, “Experimental Analysis of High Temperature Shape Memory Polymers for Deployable Structures”, submitted in June 2019. Thesis advisor is Dr. Wael Abuzaid and thesis co-advisor is Dr. Maen Alkhader. Soft and hard copy available.Shape Memory Polymers (SMP) continue to capture interest of the aerospace industry due to their unique properties. Compared to shape memory alloys, this class of smart materials is lighter in weight and can undergo significantly larger recoverable deformations. However, the recovery stresses, and therefore the loads that can be supported, are inferior compared to shape memory alloys. This limitation has triggered efforts to develop Shape Memory Polymer Composites (SMPC), using SMP epoxy resins, with the ability to overcome the aforementioned drawback. However, the focus has been on SMPs with low transformation temperatures below 100°C. On the other hand, certain aerospace applications require shape memory polymers with higher transformation temperatures to prevent undesirable actuation upon heat exposure. Moreover, and despite significant work on characterizing mechanical and recovery properties of shape memory polymers, the literature lack full field characterization of recovery properties, in particular at elevated temperatures. In this work, a high temperature thermoset epoxy SMP (Tg ~ 130°C), named EPON SMP, is thoroughly investigated. The study provides comprehensive experimental analysis of the mechanical and shape memory properties of the aforementioned high temperature epoxy SMP. In addition, this study uses a full-field characterization technique, Digital Image Correlation (DIC), to provide further insight on localization, heterogeneity and local recovery of shape memory strains. Furthermore, the study evaluates the recovery properties of SMP samples programmed at different loading conditions (i.e. bending, tensile) and proposes shape-recovery evaluation methods that can be later implemented on other SMPs. The EPON SMP samples were successfully manufactured and evaluated in this work. Stress free shape recovery was observed for SMP samples programmed at different loading conditions (i.e. bending, tensile). Moreover, the recovery rate was found to be dependent on programmed strain level and recovery temperature. Furthermore, the SMP displayed less shape recovery while under stress. Degradation in the SMP’s ductility was observed at elevated temperatures. In addition, the effects of thermal stresses and strains were quantified and observed to be highly significant in the SMP programming and shape recovery processes.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Constructing National Identity through the Lens of the Painted Panorama: The Bourbaki Panorama in Lucerne, Switzerland
No full textUsing the Bourbaki Panorama, which depicts the French General Charles-Denis Bourbaki’s army crossing Switzerland’s border near Les Verrières in 1871, this paper examines the notion of identity narrative in nation-building and addresses the following questions: How does the Bourbaki Panorama reinforce Switzerland’s national identity? How can identity narratives strengthen or challenge a nation’s collective memory? How can these findings inform current and future practices in the development and interpretation of new and existing panorama projects
Verbal negation in the Lebanese dialect of Zeitoun, Keserwan
No full textThe dialect of Zeitoun village in the northern Keserwan district of Lebanon exhibits both the split-morpheme negators mā…š of the southern and highland Levant and the pre-verbal negator mā without the post-positive -š of the northern Levant, with the -š of negation optionally appearing in identical contexts. It also exhibits the form a…š of southern and highland Levantine Arabic dialects. Some researchers propose that the negator a- can only appear before labial consonants, such as the b- prefix marking habitual action or imminent futurity. Others note that it may also occur with the prohibitive, usually marked by the 2nd-person prefix t-. Neither of these observations holds for the Zeitouni dialect, in which prohibitives negated with sole -š may be formed without the prefix, the initial consonant being whatever the radical might be. Sole post-positive -š also occurs in negation of an unmarked imperfective verb, there, too, sometimes without an overt proclitic person marker. Another feature that is occasionally noted in the literature is the negation of perfective verbs with sole post-positive -š. This, too, occurs in the Zeitouni dialect. This type of verbal negation is characteristic of dialects from the Lebanese highlands and through the Ḥawrān. Finally, it is noticed that a word-final consonant cluster generated by the enclitic -š does not necessarily attract stress