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Re-Presenting Cultural Heritage with VR Panoramic Photography: Lessons Drawn from Media Art History
No full textDeveloping a history of virtual reality (VR) panoramic photography not only in relation to the development of illusion and immersion, but also its content, will allow for a more robust history, so that those who are working within VR panoramic photography are not "reinventing the wheel" and a greater critical discourse may take place as this medium develops. Within a media art history context, past disruptive immersive deliverables include the vue d'optique, panorama and stereoview. Nevertheless, a recurring theme, which ties the content used in these deliverables with VR panoramic photography, is the re-presentation of cultural heritage. Using examples of the re-presentation of Middle Eastern cultural heritage from media art history, this essay explores the following questions: how has the re-presentation of Middle Eastern cultural heritage changed or shifted as these technological disruptors have been introduced and used, and how can one use these past innovations to inform contemporary best practices in cultural heritage preservation, interpretation, and dissemination using VR panoramic photography? The paper will conclude with practical, useful recommendations to inform current and future initiatives in developing artistic projects that use VR panoramic photography for the preservation, interpretation, and dissemination of cultural heritage
Numerical Analysis for Film Cooling Performance Under Different Jet Design Criteria
No full textA Master of Science thesis in Mechanical Engineering by Mohammed Aref Al-Hemyari entitled, “Numerical Analysis for Film Cooling Performance under Different Jet Design Criteria”, submitted in April 2018. Thesis advisor is Dr. Mohammad Omar Hamdan and thesis co-advisor is Dr. Mehmet Fatih Orhan. Soft and hard copy available.Cooling gas turbine blades is a crucial technique to allow higher turbine inlet temperatures. A higher turbine inlet temperature allows boosting gas turbine efficiency, which reduces fuel consumption. One of the main cooling techniques of the turbine blades is film cooling where a relatively low air temperature is used to form a blanket of cool air around the blade to shield it from high temperature gases. Many complex interrelated geometry and flow parameters affect the effectiveness of the film cooling. The complex interrelations between these parameters are considered the main challenge in properly understanding the effect of these parameters on film cooling. Testing such cooling techniques under actual engine conditions is even more challenging due to difficulty of installing proper instrumentations. Numerical techniques are viable analysis techniques that are used to better understand film cooling techniques. In this study, a simplified 2D film cooling jet blown from the slot jet is investigated under multiple variable parameters, mainly, the blowing ratio, jet angle, density ratio and centrifugal force. The performance of the film cooling is reported using local and average adiabatic film effectiveness. The main contribution of this study is exploring the effect of the centrifugal force and wall material selection using conjugate heat transfer on film cooling effectiveness. The centrifugal force reduces the overall adiabatic film effectiveness. A correlation between the blowing ratio, density ratio and injection angle is developed in this work. The highest film cooling performance was founded at a blowing ratio of 0.8, an injection angle of 30° and density ratio of 1.2.College of EngineeringDepartment of Mechanical EngineeringMaster of Science in Mechanical Engineering (MSME
Hybrid Power System Design for Autonomous Ground Robots
No full textA Master of Science thesis in Mechatronics Engineering by Ali Qahtan Al-Tameemi entitled, “Hybrid Power System Design for Autonomous Ground Robots”, submitted in November 2018. Thesis advisor is Dr. Shayok Mukhopadhyay. Soft and hard copy available.The interest in mobile robots has increased rapidly due to the complicated tasks a mobile robot can accomplish. An efficient robot power supply system can increase the robot range of travel. Different power management techniques have been applied heavily in the field of electric vehicles. Such techniques are helpful in terms of extending the robot driving range; power controller requires placing a DC converter that consists of power switches, inductors, and capacitors. In most cases, robots are still powered by a single battery. This observation inspired this work to develop an enhanced passive multi-source power system, using Generalized Predictive Control (GPC) and Kalman filtering (KF) to find the minimum power required to drive the robot along a predefined path. As a result, the designed power system extends robot driving range from 3 to 16 hours. Since batteries are a major component of any current hybrid energy system design, any good energy management system must incorporate an impending battery failure detection system, so that other energy sources can be switched on to replace a dying battery. This work proposes a battery voltage collapse detection technique based on Fast Fourier Transforms (FFTs) and artificial neural network (ANNs), where the robot driving range is extended more by 3 hours using a backup battery. This work aims to use two batteries, a supercapacitor, and a fuel cell based system to form a long-lasting hybrid energy system for a mobile robot.College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR
Optimal Management of Mobile Energy Generation and Storage Systems
No full textA Master of Science thesis in Electrical Engineering by Sarra Mahmoud Samara entitled, “Optimal Management of Mobile Energy Generation and Storage Systems”, submitted in December 2018. Thesis advisor is Dr. Mostafa Shaaban. Soft and hard copy available.As the global demand for energy increases, new technologies are needed to satisfy the necessity for the electrical network growth. As part of a Smart Grid (SG), Distributed Energy Resources (DERs) are adopted to enhance the efficiency, stability, reliability, and the power quality of the electric grid, in addition to, deferring the need for network upgrades. However, in many cases, there is a temporary need for a DER supply such as during peak grid prices, planned outages, and forced outages. Thus, a mobile energy resource can be utilized in these cases to serve several customers. The research presented in this thesis proposes a new approach to optimally dispatch and schedule a Mobile Energy Generation and Storage System (MEGSS) fleet of electric trucks that encompass three types of DER, namely photo-voltaic (PV) panels, dispatchable generator, and battery energy storage system (BESS). The aim of the proposed approach is to maximize the profit of the MEGSS while meeting customers' requirements. The outcomes of the proposed approach are the day-ahead optimal decisions regarding the customers to be served, the route to be followed by each MEGSS in the fleet, and the onboard resources scheduling. To develop these optimal decisions, the proposed approach utilizes traffic information, customers’ requests, PV generation forecast, and offered energy and demand charges. The MEGSS dispatch problem is formulated as a mixed-integer non-linear programming (MINLP) problem, which is decomposed into two sub-problems: an outer problem and an inner problem. The outer problem decides on the customers to be served and the route to be followed, while the inner problem decides on the onboard resources scheduling. The resulted optimal decisions will be used by the dispatch center to mobilize and schedule the fleet of MEGSS units.The proposed approach has been tested on a typical set of 19 industrial customers to optimally dispatch a sample fleet of two trucks. Results show a maximum daily profit of ＄945 by using two trucks. The suggested method successfully achieved the anticipated goal of the system of attaining maximum profits by reducing daily operation costs.College of EngineeringDepartment of Electrical EngineeringMaster of Science in Electrical Engineering (MSEE
Kinetic and thermodynamic study of phosphate removal from water by adsorption onto (Arundo donax) reeds
No full textThe adsorption of phosphate ion onto natural reed (Arundo donax) was studied in this work. The effect of phosphate initial concentration, adsorbent dose, pH, temperature, and salt addition on adsorption uptake was investigated. The results showed that the adsorption uptake is directly proportional to the phosphate ion initial concentration and inversely proportional to the adsorbent's dose and temperature. A maximum adsorption capacity of 16.2 mg/g was observed at neutral pH. The addition of sodium and potassium chlorides has decreased the adsorption uptake. The adsorption isotherms agree better with the Langmuir model. The negative values of (ΔG) and (ΔH) obtained from the thermodynamic study, indicted that the adsorption process is spontaneous and exothermic. The experimental adsorption data were analyzed using three kinetic models: pseudo-first order, pseudo-second order, and intra-particle diffusion model. The pseudo-second-order model presented the best fit with a determination coefficient (R2) higher than 0.99 and a minimum normalized standard deviation
Mixed Silver-Zinc Encapsulated Zeolite-Y Powders Toward the Photodegradation of Aqueous Fenoxycarb Solutions
No full textMixed silver–zinc doped in zeolite Y was prepared via cation exchange process. Two samples with various silver and zinc contents were prepared as well as two samples modified with microwave treatment before the calcination process. The prepared samples behave as good adsorbents towards fenoxicarb where up to 30% of the pesticide was removed from solutions upon mixing for one minute. In addition, all of the modified materials tend to enhance the photo-degradation of fenoxicarb when irradiated at 254 nm UV light. The study indicates that Ag-ZnY1 (10.7% Ag and 10.32% Zn) provides the best catalytic activity towards the degradation of fenoxycarb where the rate constant was 0.041 min–1 compared to the observed rate constant of 0.0162 min–1 for the similar test without a catalyst. In addition, both microwave samples provide an enhancement in the photo-degradation by 1.6–1.7 times compared to the zeolite-free samples. The data showed that silver played the major role in the observed catalytic activity. For example, the rate constant of the Ag-ZnY1M sample (1.8% Ag and 0.20% Zn) was 0.0283 min–1 while the reaction proceeds with a rate constant of 0.0270 min–1when Ag-ZnY2M (0.90% Ag and 0.30% Zn) catalyst was used. GC-MS analysis of the irradiated solution of fenoxycarb for 60 min showed the formation of 4-(2-aminoethoxy) phenol ethane as the major product
Removal of Heavy Metals from Wastewater Using Multiwalled Carbon Nanotubes
No full textA Master of Science thesis in Chemical Engineering by Malaz Suliman entitled, "Removal of Heavy Metals from Wastewater Using Multiwalled Carbon Nanotubes," submitted in April 2017. Thesis advisor is Dr. Taleb Ibrahim. Soft and hard copy available.Recently, carbon nanotubes have been employed as new adsorbent for the removal of many pollutants. In this study, raw multiwalled carbon nanotubes (MWCNTs) were firstly tested for the removal of lead from aqueous solutions. Then, sodium lauryl sulfate modified multiwalled carbon nanotubes (SLS-MWCNTs) were produced, characterized and used for lead removal. Surface characterization using energy dispersive X-ray spectroscopy (EDS), thermogravimetric analyzer (TGA) and Fourier transform infrared spectroscopy (FTIR) showed that surface modification has been achieved successfully. Adsorption results revealed that the surface modification has increased the adsorption capacity from 3.84 mg/g for raw-MWCNTs to 141 mg/g for SLS-MWCNTs. On the other hand, the optimum values of some important parameters were determined. Optimum values of adsorbent dosage, contact time, pH and temperature using raw-MWCNTs were found to be 15.0 g/L, 50 min, 6.5 and 25 °C, respectively and for the SLS-MWCNTs the optimum parameters were found to be 3.00 g/L, 30 min, 5.3 and 25 °C, respectively. Fitting equilibrium data on different isotherm models showed that adsorption on raw-MWCNTs follows Langmuir model with qm = 3.84 mg/g and KL = 0.29 L/mg, while adsorption on SLS-MWCNTs is best described by Freundlich model with n = 2.50 and KF = 15.40 (mg0.6. L0.4)/g. Furthermore, kinetics study results revealed that both raw and SLS-MWCNTs follow the pseudo second order model with rate constants 0.11 g/mg.min and 0.06 g/mg.min, respectively. Thermodynamics study showed that mode of adsorption is physisorption on both raw and SLS-MWCNTs with ∆G values -0.45 and -9.21 kJ/mol at 25 °C, respectively. In order to get higher density particles with more granular structure to enhance column operation, magnetite pellets of SLS-MWCNTs were prepared and used in packed bed column. Column data were found to fit well by the modified dose response model with parameters values qmdr = 28.4 mg/g and a' = 3.47 mg-1.College of EngineeringDepartment of Chemical EngineeringMaster of Science in Chemical Engineering (MSChE
Acoustic Energy Harvesting using Dual Piezoelectric Plates
No full textA Master of Science thesis in Mechatronics Engineering by Maleka AbdulBari Bin Tarsh entitled, "Acoustic Energy Harvesting using Dual Piezoelectric Plates," submitted in May 2017. Thesis advisor is Dr. Jin-Hyuk Lee. Soft and hard copy available.Sound is abundant energy found in our everyday lives, especially in urban places. Acoustic energy can be thought of as a good alternative energy source. Despite the fact that the sound is prevalent; it is challenging to scavenge energy for practical application due to the low-power density. However, the harvested energy from acoustics can be used to power low-power electronic devices. Researchers have established various techniques and mechanisms to increase the harvested energy at the low frequency range. One widely famous and effective mechanism is the use of piezoelectric (PZT) transducers. This technique has been used by many researchers to maximize the energy harvested from sound (vibration). Dual piezoelectric cantilever plates will be employed to harness the acoustic waves and obtain the natural frequency. The natural frequency is first determined through a proposed mathematical model and it is found to be 247 Hz. Then, the natural frequency is verified by a numerical method used by COMSOL Multiphysics software and it is found to be 242 Hz. This frequency is then validated with experimental data and it found to be 239 Hz; which is close to the mathematical and simulation results. The dual piezoelectric cantilever plates will be placed inside a quarter-wavelength straight-tube resonator. The tube resonator works as an amplifier when an incident wave travels through it. An acoustic resonant wave is applied and drives the PZT plates causing it to generate energy. The amplification ratio is 3.58 dB at the resonant frequency (239 Hz). Several tests are carried out to validate the resonant frequency within the tube resonator and it is verified to be 239 Hz. Furthermore, multiple tests are conducted with tube resonator placed at different locations from the acoustic source. Those tests confirmed that the maximum voltage is produced at the resonant frequency (239 Hz). The goal of this research is to find an improved way to harvest the currently wasted acoustic/vibration energy through piezoelectric cantilever plates.College of EngineeringMultidisciplinary ProgramsMaster of Science in Mechatronics Engineering (MSMTR
Forward Osmosis Desalination Using Ferric Sulfate Draw Solute
No full textLack of suitable draw solutes is one of the major limiting factors hindering commercial realization of forward osmosis (FO) desalination process. This study investigates the feasibility of ferric sulfate as draw solute in FO desalination. A laboratory-scale, cross-flow FO apparatus utilizing commercial FO membrane (cellulose triacetate-based) was used to desalinate synthesized (5000 ppm NaCl) brackish water and (40,000 ppm NaCl) seawater using 280,000 ppm ferric sulfate draw solution at ambient conditions. The observed average water flux was 3.75 and 1.61 L/m2 h in case of brackish and seawater, respectively. Using deionized water as feed solution, reverse ferric sulfate flux of 1.88 g/m2 h was observed. Product water was recovered from the diluted draw solution by precipitation reaction using barium hydroxide. Pure water samples with salt contents of 60 and 80 ppm were obtained by desalinating brackish and seawater feed, respectively
Sustainability of Carbon Nanotube-Reinforced Concrete
No full textConcrete, despite being one of the most produced materials in the world, still has weaknesses and drawbacks. Significant concern of the cementitious materials in structural applications is their quasi-brittle behavior, which causes the material to crack and lose its durability. One of the very recently proposed mitigations for this problem is the implementation of nanotechnology in the concrete mix by adding carbon nanotubes (CNTs) to it. CNTs can enhance the critical mechanical properties of concrete as astructural material. Thus, this paper demonstrates a state-of-the-art review of reinforcing concrete with CNTs, emphasizing on the structural performance. It also goes over the properties of CNTs alone, the present methods and costs associated with producing them, the possible special applications of concretes reinforced with CNTs, the key challenges and drawbacks that this new technology still encounters, and the most reliable practices and methodologies to produce CNT-reinforced concrete in the lab. This work has shown that the addition of CNTs to the concrete mix in percentages as low as 0.25% weight of cement could increase the flexural strength and toughness of concrete by more than 45% and 25%, respectively, and enhance other durability-related properties, given that an effective dispersion of CNTs in the cementitious mix is achieved. Since nano reinforcement for cementitious materials is a new technology, many challenges have to be tackled before it becomes practiced at the mass level