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Full-Text Articles in Engineering

Homogeneous Reaction Kinetics Of Carbohydrates With Viologen Catalysts For Biofuel Cell Applications, Hilary Bingham Jul 2018

Homogeneous Reaction Kinetics Of Carbohydrates With Viologen Catalysts For Biofuel Cell Applications, Hilary Bingham

Theses and Dissertations

Energy usage is continually on the rise and significant efforts are being extended to provide more renewable energy. One area of exploration is the development of fuel cells, which includes biofuel cells that can extract energy from carbohydrates obtained from biomass. Recently, viologen catalysts have been shown to enhance reaction rates of energy extraction and improve carbohydrate conversion efficiencies. However, characterizing the effects of process parameters such as pH, reactant concentrations, and carbohydrate exposure time to buffer solutions with a rigorous model is lacking. This thesis characterizes the homogeneous reaction between carbohydrates and a methyl viologen catalyst to provide insights …

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Tactile Sensing And Position Estimation Methods For Increased Proprioception Of Soft-Robotic Platforms, Nathan Mcclain Day Jul 2018

Tactile Sensing And Position Estimation Methods For Increased Proprioception Of Soft-Robotic Platforms, Nathan Mcclain Day

Theses and Dissertations

Soft robots have the potential to transform the way robots interact with their environment. This is due to their low inertia and inherent ability to more safely interact with the world without damaging themselves or the people around them. However, existing sensing for soft robots has at least partially limited their ability to control interactions with their environment. Tactile sensors could enable soft robots to sense interaction, but most tactile sensors are made from rigid substrates and are not well suited to applications for soft robots that can deform. In addition, the benefit of being able to cheaply manufacture soft …

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Smart Technologies For Oil Production With Rod Pumping, Brigham Wheeler Hansen Jul 2018

Smart Technologies For Oil Production With Rod Pumping, Brigham Wheeler Hansen

Theses and Dissertations

This work enables accelerated fluid recovery in oil and gas reservoirs by automatically controlling fluid height and bottomhole pressure in wells. Several literature studies show significant increase in recovered oil by determining a target bottomhole pressure but rarely consider how to control to that value. This work enables those benefits by maintaining bottomhole pressure or fluid height. Moving Horizon Estimation (MHE) determines uncertain well parameters using only common surface measurements. A Model Predictive Controller (MPC) adjusts the stroking speed of a sucker rod pump to maintain fluid height. Pump boundary conditions are simulated with Mathematical Programs with Complementarity Constraints (MPCCs) …

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Antimicrobial Properties And Characterization Of Polymer/Composite Nanofibers, David De La Garza Jul 2018

Antimicrobial Properties And Characterization Of Polymer/Composite Nanofibers, David De La Garza

Theses and Dissertations

Pathogenic bacteria have been the cause of many illnesses worldwide due to their rapid growth and reproduction in food and water. Bacteria-resistant antibiotics and kidney complications due to overuse of antibiotics has remained a large public health concern. The goal of this research project was to find an alternative by producing nanofibers that inhibit microbial growth utilizing Forcespinning technology. The Forcespinning of poly(acrylic acid) (PAA) with Single Wall Carbon Nanotubes functionalized with OH (SWCNT-OH) and Ag + flakes were carried out on solutions with different concentrations. Scanning electron microscopy was used to view fiber morphology and investigate the average nanofiber …

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Forcespinning Of Metal Oxides And Metal Sulfides And Their Applications As Alternative Anode Materials For Lithium-Ion And Sodium-Ion Batteries, Alejandra Valdez Jul 2018

Forcespinning Of Metal Oxides And Metal Sulfides And Their Applications As Alternative Anode Materials For Lithium-Ion And Sodium-Ion Batteries, Alejandra Valdez

Theses and Dissertations

Molybdenum-Oxide/Carbon (MoO2/C) composite nanofibers were synthesized using Forcespinning method and subsequent heat treatment, for use as anode materials for lithium-ion batteries. Due to the layered structure of MoO2, the composite nanofibers are very promising for use as anode material for LIBs. The MoO2/C composite fiber anodes exhibit good electrochemical performance and cycling stability.

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Direct Numerical Simulations Of Incompressible Flow Through Porous Packs Over A Wide Range Of Reynolds Numbers, Antoine Michael Diego Jost Jul 2018

Direct Numerical Simulations Of Incompressible Flow Through Porous Packs Over A Wide Range Of Reynolds Numbers, Antoine Michael Diego Jost

Theses and Dissertations

Direct numerical simulations of incompressible flow through periodic square/rectangular (two-dimensional; 2-D) and cubic (three-dimensional; 3-D) arrays of particles and periodic random packs of polydisperse spheres over a wide range of Reynolds numbers and at various porosities are performed. The unsteady Navier- Stokes equations are solved with either a 3-D parallel finite-difference (FD) inhouse research code on a collocated Cartesian grid and with an immersed boundary method (IBM) to treat the internal boundaries, or with the finite-volume (FV) solver OpenFOAM R⃝ on an unstructured grid and with an explicit treatment of the boundaries. The FD explicit solver is used for 2-D …

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An Analysis Of The Relationship Between Orthopedic Drill Bit And Screw Diameter On Drilling Energy And Axial Load Pullout Strength, Scott J. J. Baskerville Jul 2018

An Analysis Of The Relationship Between Orthopedic Drill Bit And Screw Diameter On Drilling Energy And Axial Load Pullout Strength, Scott J. J. Baskerville

Theses and Dissertations

The number of orthopedic procedures performed per year in the United States is expected to grow to 6.6 million by 2020 (1). Most of these surgeries involve some degree of bone drilling and screw fixation, putting many patients at risk of the adverse effects of the heat-induced osteonecrosis which can limit the holding strength of bone screws and the efficacy of the screw-dependent fixtures. Excessive heat-induced osteonecrosis can occur when surgeons prolong the drilling procedure to avoid drill plunge, which can cause damage to soft neurovascular tissues local to the drilling site (2). The SMARTdrill system used in this study …

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Isru Thermal-Driven Processes On Interplanetary Surfaces And Characteristics On Production Of Commodities, Jesus A. Dominguez Jul 2018

Isru Thermal-Driven Processes On Interplanetary Surfaces And Characteristics On Production Of Commodities, Jesus A. Dominguez

Theses and Dissertations

Extraterrestrial In-Situ Resource Utilization (ISRU) is a primary area of interest to enable successful exploration, mining, and human settling in space missions. Native extraterrestrial conditions, such as vacuum conditions and low gravity are challenging as their effects on workable-scale ISRU operations are basically unknown. This dissertation research work studied three thermal-driven properties on JSC-lA lunar regolith simulant at pilot-plant-­scale under vacuum (a native ambient condition on the moon and asteroids): (1) gasification and decomposition of regolith's components that have the potential of generating gaseous oxygen, metals, and alloys without the necessity of terrestrial precursors, (2) vacuum void formation during the …

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Adaptive Spaceship Cockpit Architecture, Ondřej Doule Jul 2018

Adaptive Spaceship Cockpit Architecture, Ondřej Doule

Theses and Dissertations

This research project is focused on a system design theory and practice of the most complex environment that a human-system architect can ever encounter. It is the environment of the spaceship cockpit or cabin that is affected by forces of propulsion and gravity accelerations and freefall while the direction and magnitude of gravity change during the flight. Furthermore, the hyperbaric, restrictive environment of Intra Vehicular Activity spacesuit adds another layer of complexity. In off-nominal or emergency situations, these environmental effects combine, which results in specific human-system interaction requirements. Considering human-system integration requirements on safety, comfort and efficiency of communication between …

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Tornado And Hurricane Hazards: Reconnaissance, Structural Analysis And Vulnerability Modeling, Fernando Simon Plaz Jul 2018

Tornado And Hurricane Hazards: Reconnaissance, Structural Analysis And Vulnerability Modeling, Fernando Simon Plaz

Theses and Dissertations

This thesis is composed of three main projects which are directly linked to wind engineering. Hazards such as tornadoes and hurricanes are natural disasters which causes human and economic losses. First, the study consists on a forensic analysis made to a Tornado that hit Funing and Sheyang counties, in the Jiangsu Province of China. 21 villages, mostly rural, experienced important damages to different type of structures. The work will describe field observations and structural analyses made to communication towers. Preliminary estimates of wind speeds will be given based on the observations and the analysis as well as recommendations to reduce …

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Development Of A Small Diameter Rapid Pressuremeter Test For Unbound Pavement Layer Evaluations, Thaddeus Joseph Misilo Iii Jul 2018

Development Of A Small Diameter Rapid Pressuremeter Test For Unbound Pavement Layer Evaluations, Thaddeus Joseph Misilo Iii

Theses and Dissertations

Six inch and 12 inch long small diameter pressuremeter (SDPMT) probes were developed and tested extensively to determine in situ stress-strain properties of unbound pavement layers. They were deployed in the same hole as the one made during nuclear density testing. The stress strain response of conventional or incremental and continuous or rapid strain controlled tests in unbound pavement layers were evaluated at four sites in Brevard County, Florida. One test site was A-1-b base material, one was A-3 subgrade and two were compacted A-3 fill of subgrade quality. The SDPMT results were compared with nuclear density dry and wet …

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A Robot Fdm Platform For Multi-Plane And 3d Lattice Structure Printing, Ismayuzri Bin Ishak Jul 2018

A Robot Fdm Platform For Multi-Plane And 3d Lattice Structure Printing, Ismayuzri Bin Ishak

Theses and Dissertations

Additive manufacturing is a process to fabricate three-dimensional (3D) objects usually by joining a material layer by layer. The layer by layer joining process simplifies the fabrication method by slicing the 3D object into stacks of 2D contours. The layers are combined in a single build direction to form the 3D object. The purpose of this research is generate new knowledge in additive manufacturing process by integrate a six degree of freedom robot arm platform with a fused deposition modeling system entitled MotoMaker for additive manufacturing applications. The development of a higher degree of freedom additive manufacturing platform allows for …

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Design And Characterization Of A Plunge-Capable Friction Stir Welding Temperature Feedback Controller, Jonathan David Erickson Jul 2018

Design And Characterization Of A Plunge-Capable Friction Stir Welding Temperature Feedback Controller, Jonathan David Erickson

Theses and Dissertations

Temperature control in friction stir welding (FSW) is of interest because of the potential to improve the mechanical and microstructure characteristics of a weld. Two types of active temperature control have been previously implemented for steady-state friction stir welding conditions: PID Feedback Control and Model Predictive Control. The start-up portion of a weld is an obstacle for these types of active control.To date, only minimal exploratory research has been done to develop an active temperature controller for the start-up portion of the weld. The FSW temperature controller presented in this thesis, a Position-Velocity-Acceleration (PVA) controller implemented with gain-scheduling, is capable …

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Body Armor Shape Sensing With Fiber Optic Sensors, Frederick Alexander Seng Jul 2018

Body Armor Shape Sensing With Fiber Optic Sensors, Frederick Alexander Seng

Theses and Dissertations

In this dissertation, the rate of the BFD during body armor impact is characterized with fiber Bragg gratings for the first time ever. The depth rate is characterized using a single fiber optic sensor, while the entire shape rate can be characterized using multiple fiber optic sensors. This is done with a final depth accuracy of less than 10% and a timing accuracy of 15% for BFDs as deep as 50 mm and impact event of less than 1 millisecond. The shape sensing method introduced in this dissertation is different from traditional fiber optic sensor shape reconstruction methods in the …

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Fundamental Investigation Of Magnesium Corrosion Using Experiments And Simulation, Dila Ram Banjade Jul 2018

Fundamental Investigation Of Magnesium Corrosion Using Experiments And Simulation, Dila Ram Banjade

Theses and Dissertations

Magnesium (Mg) is the lightest of all structural metals and has tremendous potential for applications in the lightweight industry. However, the corrosion of Mg is a significant barrier towards its wider use. Despite years of research, the fundamental understanding of Mg corrosion still remains short. The enhanced hydrogen evolution reaction (HER) with anodic polarization, the modeling of galvanic corrosion and the impact of hydrogen bubbles for galvanically coupled Mg are important aspects of Mg corrosion that need to be understood before any mitigation measures can be taken. The results presented in this work provide a key step in that direction. …

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Inference Framework For Model Update And Development, Xiao Lin Jul 2018

Inference Framework For Model Update And Development, Xiao Lin

Theses and Dissertations

Computational models play an important role in scientific discovery and engineering design. However, developing computational models is challenging, since the process always follows a path contaminated with errors and uncertainties. The uncertainties and errors inherent in computational models are the result of many factors, including experimental uncertainties, model structure inadequacies, uncertainties in model parameters and initial conditions, as well as errors due to numerical discretizations. To realize the full potential in applications it is critical to systematically and economically reduce the uncertainties inherent in all computational models.

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Evaluation And Design Improvement Of An Augmentative And Alternative Communication Tool For Children With Autism, Moez Lidinallah Fessi Jul 2018

Evaluation And Design Improvement Of An Augmentative And Alternative Communication Tool For Children With Autism, Moez Lidinallah Fessi

Theses and Dissertations

Autism Spectrum Disorder treatment is a real challenge in our society. In an attempt to manage this, Augmentative and Alternative Communication devices became more and more prevalent in the form of software installed on portable devices such as tablets. These mobile applications help individuals with autism to enhance their communication capabilities. Some of the concerns pertaining to the success these systems are the efficacy and the capability, the ease of use, and the user engagement. The research described in this thesis focuses on the usability of a particular application named Livox. This usability evaluation consisted of a threefold approach: (1) …

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A Framework And Exploration Of A Cybersecurity Education Escape Room, Justin Charles Snyder Jul 2018

A Framework And Exploration Of A Cybersecurity Education Escape Room, Justin Charles Snyder

Theses and Dissertations

This thesis presents a review of educational-escape-room literature followed by a design-oriented framework (the Snyder Escape Room Framework or SERF) and demonstrates the potential efficacy of escape-rooms in cybersecurity education. Several authors have proposed frameworks and guidelines for game and educational design regarding escape rooms. This work coalesces some of those ideas into a more substantial and comprehensive framework (SERF) that designers can use when developing educational escape rooms. The Snyder Escape Room Framework provides heuristics for goals and objectives, players, activities, context, trajectory design, and evaluation. Additionally, this work describes and analyzes the novel prototyped BYU GCC escape room …

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Control Laws For Autonomous Landing On Pitching Decks, Kendrick Buchala Jul 2018

Control Laws For Autonomous Landing On Pitching Decks, Kendrick Buchala

Theses and Dissertations

This thesis addresses the problem of landing a quadcopter onto the pitching deck of a ship, as a partial simulation of a shipboard landing during high seas. The deck is modeled to pitch with a sinusoidal motion. While shipboard landing consists of many stages, only the final landing is simulated in this research. Other ship motions, such as roll and heave, are likewise not considered. The goal is to land the quadcopter in the center of the deck with minimal position and pitch error, where position error measures how far fore or aft of the center of the landing pad …

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Dynamics Of Spacecraft Orbital Refueling, Casey Clark Jul 2018

Dynamics Of Spacecraft Orbital Refueling, Casey Clark

Theses and Dissertations

A quantitative collation of relevant parameters for successfully completed experimental on-orbit fluid transfers and anticipated orbital refueling future missions is performed. The dynamics of connected satellites sustaining fuel transfer are derived by treating the connected spacecraft as a rigid body and including an internal mass flow rate. An orbital refueling results in a time-varying local center of mass related to the connected spacecraft. This is accounted for by incorporating a constant mass flow rate in the inertia tensor. Simulations of the equations of motion are performed using the values of the parameters of authentic missions in an endeavor to provide …

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Human-Centered Design Of A 3d-Augmented Strategic Weather Management System For The Aviation Community, Sébastien Léonce Paul Boulnois Jul 2018

Human-Centered Design Of A 3d-Augmented Strategic Weather Management System For The Aviation Community, Sébastien Léonce Paul Boulnois

Theses and Dissertations

Convective weather is one of the main causes of accidents in the National Airspace System according to the Federal Aviation Administration. The purpose of this research, aligned with current NextGen research efforts, was to determine how weather information, presented in 2D and/or 3D, and associated with interaction features, could impact airline pilots’ weather-related situation awareness and decision-making capabilities. Human-Centered Design principles, along with Design Thinking, were used and led to the design of a 3D-Augmented Strategic Weather Management System aiming to satisfy this research question. The system is called “Onboard Weather Situation Awareness System” (OWSAS) in the scope of this …

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Improving Stb Devices’ Parental Control, Mahmood Fawzi Alfathe Jul 2018

Improving Stb Devices’ Parental Control, Mahmood Fawzi Alfathe

Theses and Dissertations

In this dissertation, an IPTV system was designed with new viewer parental control authentication method. People deal with traditional IPTV systems that use simple authentication numeric passcodes, and this topic did not receive the attention to overcome its security problems. In this dissertation two contributions were introduced, the first one is to design and implement an IPTV system that uses humans’ Biometrics authentication instead of numeric passwords; the second contribution was presented by integrating and testing the efficiency of the suggested solution as an authentication key against traditional numerical passcodes. Also, the characteristics of this new method were tested. In …

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Optimizing Dynamic Range For Micro-Electro-Mechanical Resonators, Douglas John Schoeller Jul 2018

Optimizing Dynamic Range For Micro-Electro-Mechanical Resonators, Douglas John Schoeller

Theses and Dissertations

The performance of microelectromechanical systems (MEMS) is a topic that attracts attention from the scientific community due to their diverse applications. The use of MEMS has been applied to areas of medicine, timing, sensing, and microfluids to name a few. This work seeks to enhance the performance of a MEM resonator by optimizing its linear dynamic range (LDR) through the idea of combining the mixed nonlinear effects that stem from mechanical and electrostatic forces. The modeling procedure in this work incorporates the third-order Duffing model and includes an electrostatic effect that is expanded to the fifth order nonlinearity. When involving …

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An Empirical Path Loss Model For Wireless Sensor Network Deployment In A Library Environment, Thomas John Misilo Jul 2018

An Empirical Path Loss Model For Wireless Sensor Network Deployment In A Library Environment, Thomas John Misilo

Theses and Dissertations

Wireless networks are becoming more commonplace which has necessitated the know-how to optimally place the devices. There have been studies using wireless sensor networks inside of libraries and museums. However, extensive research has not been completed on propagation modeling for use in the library environment. The main aim of this research is to provide a propagation path loss model for a typical library environment, while comparing two types of antennas (wire and small dipole antenna). This research develops path loss models for a peer-to-peer 2.4 GHz system, where both the transmitter and the receiver are located at the same elevated …

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Design And Simulation Of An Intelligent Self-Adaptive System For A Smart Home, Basman M. Hasan Alhafidh Jul 2018

Design And Simulation Of An Intelligent Self-Adaptive System For A Smart Home, Basman M. Hasan Alhafidh

Theses and Dissertations

Home automation and control systems as basic elements of smart cities have played a key role in the development of our homes environments . They have a wide range of applications in many fields at home such as security and monitoring, healthcare, energy, and entertainment applications. The improvement of humans’ living standards make people keep trying to delegate many of their needs to a home automation system. Such a system has been built with capabilities of predicting what the user intends to do in smart home environment. However, there are many issues that need more investigation and solutions, such as: …

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Design And Characterization Of Polymer Nanocomposites For Engineering Applications, Joseph Richard Nalbach Jun 2018

Design And Characterization Of Polymer Nanocomposites For Engineering Applications, Joseph Richard Nalbach

Theses and Dissertations

Polymer nanocomposites represent an area of materials that can yield useful properties not achievable in bulk materials. Not only can they have such properties but also they can be relatively easy to generate. With dwindling fossil fuels there is an increased need for both new methods to harvest energy and to transport the captured energy more effectively. Two separate nanocomposite materials are created to support this work with dramatically different properties, both to aid in energy efficiency. The first is an energy harvesting foam to fully utilize the structural deformability of such a material. A dissolvable sugar scaffold is combined …

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The Cost Of Jaywalking On Traffic Congestion In An Intersection In Greater Cairo: A Case Study, Hussein Gawdat Jun 2018

The Cost Of Jaywalking On Traffic Congestion In An Intersection In Greater Cairo: A Case Study, Hussein Gawdat

Theses and Dissertations

There have been many studies focusing on different types of traffic delays, pedestrians’ interaction at signalized intersections and economic losses as a result of these delays. However, there is a huge gap in the current literature, regionally and globally, in studying the traffic delays associated with jaywalking. In Egypt, jaywalking is considered a common phenomenon, however, population increased drastically over the past decades in Greater Cairo leading to more congested streets. This research provides a case study that investigates the economic effect of jaywalking on traffic flow in Mashaal, a sample location in Greater Cairo, due to traffic congestion. The …

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Creep Of Hi-Nicalon™ S Ceramic Fiber Tows At 1100°C In Air And In Silicic Acid-Saturated Steam, Logan M. Gumucio Jun 2018

Creep Of Hi-Nicalon™ S Ceramic Fiber Tows At 1100°C In Air And In Silicic Acid-Saturated Steam, Logan M. Gumucio

Theses and Dissertations

Innovations in SiC based ceramic matrix composites (CMCs) have yielded exceptional high-temperature properties and performance in aggressive oxidizing environments. These material characteristics provide potential avenues for future advancements in many applications where current metallic alloys perform near their operating temperature limits in a harsh environment. As steam (typically present in these environments) enters through cracks in the matrix of a SiC/SiC composite, it leaches Si and becomes saturated with silicic acid, Si(OH)4, prior to attacking the reinforcing SiC fibers. Therefore, it is paramount that a thorough understanding of the performance and durability of SiC fibers be obtained under …

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Mitigating Interference With Knowledge-Aided Subarray Pattern Synthesis And Space Time Adaptive Processing, Yongjun Yoon Jun 2018

Mitigating Interference With Knowledge-Aided Subarray Pattern Synthesis And Space Time Adaptive Processing, Yongjun Yoon

Theses and Dissertations

Phased arrays are essential to airborne ground moving target indication (GMTI), as they measure the spatial angle-of-arrival of the target, clutter, and interference signals. The spatial and Doppler (temporal) frequency is utilized by space-time adaptive processing (STAP) to separate and filter out the interference from the moving target returns. Achieving acceptable airborne GMTI performance often requires fairly large arrays, but the size, weight and power (SWAP) requirements, cost and complexity considerations often result in the use of subarrays. This yields an acceptable balance between cost and performance while lowering the system’s robustness to interference. This thesis proposes the use of …

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Process Intervention For Water Recovery In Food Manufacture, Christian Michael Wisniewski Jun 2018

Process Intervention For Water Recovery In Food Manufacture, Christian Michael Wisniewski

Theses and Dissertations

A case study has been conducted for the recovery of water from complex wastewater at a soluble coffee manufacturing factory. The study has evaluated separation methods for process intervention based on environmental and economic assessments. Water recovery was identified in two possible wastewater streams at the factory: the overall plant effluent and an intermediate stream before it enters on-site pre-treatment. A novel vibratory field membrane separation was tested at the laboratory scale using real factory wastewater and scaled-up using appropriate design protocols. Recovery of water from the intermediate stream proved the most effective, both environmentally and economically. The full-scale vibratory …

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