Engineering Commons^™

Experimental Exploration Of Shared Magnetic Phases Between Diverse Systems Of Iron-Pnictide Superconductors, Ryan Scott Stadel

Graduate Research Theses & Dissertations

The exciting field of iron-pnictide superconductors offers unique opportunities for studying the relationship between magnetism and unconventional superconductivity. This is vital to developing an understanding of the microscopic origin of high-temperature superconductivity, which is itself an important step in harnessing such a potentially revolutionary technology.

Polycrystalline and crystalline samples are synthesized over a diverse collection of related iron-pnictide systems including (Ca,Sr,Ba)1-xNaxFe2As2, Ba(Fe1-xCox)2As2 (122s), and LaFeAs1-xPxO, and TbFeAs1-xPxO (1111s). These compounds are characterized through various types of neutron and x-ray diffraction on multiple instruments, as well as muon spin resonance, and magnetic susceptibility measurements.

A thorough investigation into the conditions under …

Simulation Of Particle Transport In A Multi-Component Flow With A High Viscosity Ratio Driven By Slender Structures, Michael Roeing-Donna

Graduate Research Theses & Dissertations

Simulating particle transport in multi-component fluid flows driven by slender structures is important but challenging, especially when dealing with large viscosity ratios. In this thesis, a general multi-physics model is introduced to handle multi-component fluid flows, slender beating structures, immersed particles/droplets, and their interactions. This multi-physics model has been validated with analytical solutions and other published experimental and numerical results for the mean mucous velocity. The validated model is used to study particle transport in nasal mucous layer, the interplay between cilia and fluid flow. The model shows that mucous-pericilairy layer interface and mucous-air interface remain a constant height throughout …

Large-Scale Replication Of Anisotropic Nanostructures For Development Of Anti-Reflective Surface On Glass, Amritha Narayanan

Graduate Research Theses & Dissertations

Improvement in the Anti-reflection coating (ARC) technology is considered as one of the most important advances made in modern lens design, for microscopes, cameras, and other optical devices. In the semiconductor industry, integrated circuit (IC) chip manufactures face increasing challenges posed by reflections from the underlying substrate during photolithography, a process used for the fabrication of IC’s. Without the introduction of ARC materials, the nanoscale circuitry that drives today’s modern electronic devices would not be possible. Despite its technological significance, real materialistic solutions with low refractive index (less than 1.3) are limited. Antireflection (AR) coatings today are most often based …

Superconducting Cuprates: Synthesis, Characterization And Diffuse Scattering Properties, Bisham Poudel

Graduate Research Theses & Dissertations

Since its discovery more than a century ago, the fascinating phenomenon of superconductivity remains as mysterious as ever with the greatest challenge facing the condensed matter community being the elusive understanding of the microscopic origin leading to its inception. Many outstanding questions remain of which the role played by nematic fluctuations and structural disorder for the stabilization of superconductivity is not well understood. In this respect, superconducting YBa2Cu3O6+x (YBCO)-type cuprates present an ideal framework in which charge doping, structural disorder and various site manipulations can be explored in efforts to address some of these questions. Extensive synthesis and characterization efforts …

Developing A Standard Platform To Predict The Drag Coefficient Of Irregular Shape Particles, Amin Roostaeehosseinabadi

Graduate Research Theses & Dissertations

Solid-fluid interactions are commonly observed in natural transport phenomena and industrial applications such as sedimentation in rivers and pneumatic and hydraulic conveying of coarse particles. Here particle and fluid motion affect each other through force interactions, especially via drag force. To evaluate the magnitude of the drag force first the drag coefficient (CD) of the particle needs to be measured mostly experimentally. The CD depends on the particle’s geometry (i.e., shape, dimension, …) and the properties of the fluid medium. Since the solid particles commonly observed in nature or used in industrial setups come with irregular shapes, finding a relation …

A Theory-Supported Machine Learning Model For The Prediction Of Melt Pool Geometry And Optimal Process Window In Metal Additive Manufacturing, Sina Tayebati

Graduate Research Theses & Dissertations

Direct Energy Deposition (DED) is an additive manufacturing (AM) process capable of producing complicate-shaped or functionally graded components, and it is getting intense attention as a revolutionary technology to satisfy high demand in manufacturing process for the aerospace, automotive, and medical industries. However, the repeatability in geometries and properties of fabricated products is one of the most challenging issues for the DED process to be fully utilized, requiring comprehensive understanding of effect of processing conditions on the properties of fabricated parts, and development of relations among those conditions and properties. That is the motivation of this research. In this study, …

Object Detection And Tracking With Occlusion Handling In Autonomous Vehicles, Bhuvan Tiruttani Reddy

Graduate Research Theses & Dissertations

Object detection and tracking are important modules that need to be mastered for safe autonomous driving. Various detection and tracking algorithms have been developed in the past decade to detect and track objects accurately and efficiently in a variety of scenarios. However, most of them perform poorly during occlusion and are unable to reassociate the object IDs after the event of occlusion. In this thesis, a single unified algorithm is developed to detect, track, and display the trajectories of multiple objects in real-time, in the perceptive surroundings of an autonomous car. An Enhanced DeepSORT (EDS) tracker is proposed to better …

Design And Characterization Of Piezoelectric Actuator On Flexible Substrate For Conductive Hearing Aids, Sandhya Chapagain

Graduate Research Theses & Dissertations

Conductive hearing loss (CHL) is a common condition among infants and young children. CHL caused by an obstruction/damage in the auditory canal, preventing sounds from properly transferring into the inner ear. Failure in timely treatment in the early stage of life will delay brain and physical development, affecting language acquisition, learning abilities, communication, and social skills. The available treatment for CHL is corrective surgeries and conductive hearing aids. These options are invasive and are not suitable for newborns, infants, and pediatric patients with fragile organs. Here, we designed and characterized micro-actuators on flexible substrates to generate vibrations on the surface …

Rebuild The Niu Split-Hopkinson Pressure Bar Apparatus For High Strain Rate Tensile Test, Dian Li

Graduate Research Theses & Dissertations

A Split-Hopkinson apparatus is a device used to dynamically test material properties for constructing constitutive model and can be used for high strain rate deformation research and experiments. NIU currently has a Split-Hopkinson apparatus that can conduct compressive tests only. The goal of this thesis is to redesign and rebuild the existing apparatus, so the high strain rate tensile tests can be conducted.

Multi-improvements were applied to the Split Hopkinson apparatus in order to improve its working performance. For conducting high strain rate tensile test, the Split-Hopkinson system has been rebuilt with a load-inversion device. The load-inversion device was designed …

Coaxially Electrospun Fibrous Polymer Scaffolds For Tissue Regeneration And Drug Delivery, Matthew Michael Kleszynski

Graduate Research Theses & Dissertations

A biomaterial is a substance that is specifically engineered to take on a role within the body, either alone or in conjunction with other materials, with the purpose of influencing the body. Using Polymers as a biomaterial is an exciting field of study that has the potential to further our abilities to help those in need. Creating composite nanofibrous scaffolds composed of hydrophobic and hydrophilic polymers may outperform structures made of a single polymer in both in vitro and in vivo environments. Hydrophilicity governs the behavior of polymers in the body and has influence over the mechanical properties of the …

Development Of Prototype Rf Front-End Electronics For Linear Accelerator Beam Position Monitoring System, Edward Matthew Siebert

Graduate Research Theses & Dissertations

Beam Position Monitoring (BPM) systems are utilized extensively in particle accelerator facilities as a diagnostic tool to ascertain quantitative aspects of an accelerated charge-beam such as spatial position and intensity of the beam as it is accelerated to greater velocities and levels of kinetic energy within said accelerating machine. A critical aspect of a BPM system is the Radio Frequency Front End (RFFE) electronic circuitry that receives the incoming raw BPM signal and performs signal-conditioning such that its frequency spectrum is transformed from radio frequency (RF) to non-RF and digitization of the transformed signal by downstream components can successfully occur. …

Optimizing Sensor Locations To Improve The Worst Case Detection Performance Of Sensor Detection Systems, Ryan Taylor Vegrzyn

Graduate Research Theses & Dissertations

This thesis discusses the optimization of distributed sensor systems to maximizedetection of an emitter at an unknown location. More specifically, this thesis discusses the creation of an algorithm that seeks to optimize the spatial positions of sensors in a distributed sensor array in order to maximize the chance of detecting an emitter even if it were to occur in the worst possible location for detection. Two versions of this algorithm are discussed. The first algorithm considers a fusion rule that detects the emitter based on the sum of all sensor measurements. The second algorithm considers the scan statistic fusion rule. …

Blood Flow Simulation In A Microvascular Network, Kacper Ostalowski

Graduate Research Theses & Dissertations

Cardiovascular disease such as heart attack or stroke has been the leading cause of death in the US for over 100 years. Understanding the blood cell transport physics in a vascular network is important in both fundamental research and clinical practices. In this study, 3Dnumerical simulations on blood flow in a complex retina vascular network were performed considering deformable red blood cells (RBCs), white blood cells (WBCs), and obstructed vessels. The blood was modeled as a mixture of RBCs and WBCs suspended in fluid. The fluid was solved using the lattice Boltzmann method (LBM), and blood cells were modeled by …

Developing A Machine Learning Framework For Upwind Surveyed Regions, Witenberg Santiago Rodrigues Souza

Graduate Research Theses & Dissertations

Every year, the Oil & Gas industry loses $2B dollars due to fugitive natural gas leaks. Identifying the source of a leak is a complex challenge, especially in suburban areas where gas leakage may be mixed with other sources. Besides the multitude of possible locations for a leak in an urban area, surveying an entire city may take considerable time and funds depending on the chosen method. This work proposes a framework based on unmanned areal vehicles (UAV) to survey a region for gas leaks. To accomplish this goal, we rely on the concept of a Upwind Survey Region (USR). …

Human-Aware Information-Theoretic Control Of Robotic Swarms, Rafal David Krzysiak

Graduate Research Theses & Dissertations

Robotic swarms provide a scalable and robust solution for monitoring large environments. In this context, the inclusion of a human has the potential advantage of incorporating prior knowledge about the target location or dynamics, thus increasing the overall efficiency of the task at hand. This is especially critical when dealing with time-intensive missions such as search and rescue. In this thesis we develop a general information-theoretic framework to control multiple autonomous robots in search and rescue missions that include a human teleoperator. Human prior knowledge is modeled to capture target location and dynamics, and a mutual information based control is …

New Features For Speech Processing Standard Pronunciation Classification, Mutian Zhuang

Graduate Research Theses & Dissertations

Pronunciation is essential in language learning. Standard English speakers could pronounce in the right way, because their pronunciation procedure is correct. The aim of this research is to see how an artificial intelligence program can be developed to provide feedback to people while they learn to generate accurate phoneme /r/. The audio signal will first be detected, after which features of audio signal will be extracted, and finally, classification will be performed. This suggested algorithm and method may be applied to other related topics. This thesis proposes new features and uses them to classify standard English speakers and non-standard English …

A Dynamic Active Noise Control System For Live Music Attenuation, Elliot James Krueger

Graduate Research Theses & Dissertations

This thesis proposes a system design that will be suitable for applying active noise control (ANC) effectively to live musical instruments. The design consists of three parts: a signal separation section, an instrument classification section, and the active noise control section. The signal separation section will split up the music signals. The instrument classification section will identify the signals, and the ANC section will attenuate the music signal based on the previous information from the other sections. The two instruments of focus will be the trombone and tuba for their low frequency and ability to be quite loud in a …

Hydrocarbons In The Niobrara Formation, Powder River Basin, Northeast Wyoming, From Geophysical Well Logs, Jennifer Shilo James

Graduate Research Theses & Dissertations

The Powder River Basin, located in Wyoming, is a moderate producer of hydrocarbons with production hovering around 100 million barrels of oil per year. Recently the Niobrara Formation has garnered attention for hydrocarbon exploration and production using both conventional and unconventional drilling. A quick-look method for evaluating organic content, using either existing or real time data sets gathered from geophysical well logs, provides an opportunity to rapidly, accurately, and economically assess the formation’s organic content and thus hydrocarbon bearing potential. The popular Schmoker method determines organic content by relating gamma ray intensity to formation density. It has been successfully employed …

Modeling Study Of Electrocoagulation System For Treating Wastewater, Swachwa Dey

Graduate Research Theses & Dissertations

Effective treatment of wastewater from households, communities, and industries is vital to preserve our environment. Chemical treatment to add coagulants into the wastewater is the most popular treatment method, but due to the high operating cost and secondary contamination issue, a novel method to solve those issues is required. In this study, we revisited the electro-coagulation (EC) system which has promising features of low system/operating cost and environment friendly process. EC was actively developed once, but due to the low efficiency and scaling-up issues, it could not be fully utilized. In this study, physics-based mathematical model was developed to elucidate …

Thermal/Structural Analysis Of The Axion Quantum Metrology Cavity And Its Components, Tyler Funk

Graduate Research Theses & Dissertations

This research was centered around maximizing the capability to cool dielectric material within a containment unit, or Photonic Band Gap (PBG) cavity, designed for detecting axion dark matter and identifying the unit’s thermal properties. There are multiple types of PBG cavities, but the latest version that axion researchers wish to use has been theorized to contain possible issues related to its thermal properties. Thermal conductivity is an issue with the dielectric material because it is made from alumina which is highly insulative. This is important since the research is being done in a cryogenic environment and the thermal noise affects …

Application Of Data And Geospatial Analysis In Energy And Health Systems, Ali Faghani

Graduate Research Theses & Dissertations

Having sustainable energy and health systems are the main factors in the vision plan of every country. Both of these systems are correlated with a variety of frameworks, including social, physical, technological, political, and economic factors. Therefore, different types of analytics methods can be implemented to develop the required assessments for those who make plans since understanding the effect of such factors individually, also their interactions, and the overall effect is crucial. With this regard, applications of data analysis and geospatial techniques in both energy, and health systems have recently gained attention. The proposed research here deployed advanced data analytics …

Imu-Based Estimation Of Body Posture In Commercial Fishing, Umme Kawsar Alam

Graduate Research Theses & Dissertations

According to the U.S. Bureau of Labor Statistics (BLS), work-related musculoskeletaldisorders (WMSDs) account for 33% of all occupational injuries and illnesses in the U.S. In addition, one of the most strenuous occupations in which musculoskeletal disorders are common is known to be commercial fishing. The first step to address this issue is to precisely measure the working postures of workers so that the relation between WMSDs and nonneutral working postures can be systematically investigated. Although the inertial measurement unit (IMU) has recently gained attention in posture measurement due to its portability, it is highly limited to the use as an …

Microfluidics Design Considering Hyperuniformity And Cell Transport In Flow For Improved Circulating Tumor Cell Capture Efficiency, Michael Clarence Hood

Graduate Research Theses & Dissertations

Isolation of circulating tumor cells (CTCs) from patient derived blood samples for cancerdiagnostics and monitoring is challenging due to the extremely low CTC concentration. This thesis work evaluates the performance of passive microfluidics devices with different designs based on computational modeling. A new cell separation method is proposed based on velocity differentiation of varying cell sizes. All numerical studies were conducted in 2D based on a fluid structure interaction code where the fluid flow was solved based on the lattice Boltzmann method (LBM) implemented in Palabos, and the cell dynamics were simulated based on the molecular dynamics package LAMMPS, with …

Barcode Biosensors Based On Surface Plasmon Resonance, Sneha Ramesh

Graduate Research Theses & Dissertations

Affordable and easy to use biological assays are the current need of the day owing to the rising cost of health care within the US and worldwide. The goal of this thesis is to develop a sensitive label-free biosensing scheme exploiting surface plasmon resonance (SPR) that yields the sensor output in an easy-to-read optical bio-barcode format for high through put and multiplexed medical diagnostics. Through this research, we would like to investigate if SPR phenomena can be achieved by fabricating SP supporting metallic structures over a nanoporous dielectric layer whose optical constants are progressively varied across the substrate in a …

Clinical Applications And Feasibility Of Proton Ct And Proton Radiography, Christina Marie Sarosiek

Graduate Research Theses & Dissertations

Proton therapy is a form of radiation treatment for cancer that utilizes the Bragg peak to create conformal high dose regions around the tumor volume. However, the use of x-ray computed tomography (CT) and x-ray radiography for treatment planning and pre-treatment quality assurance procedures improves the achievable effectiveness of proton treatment plans (using proton CT) and the pretreatment verification (using proton radiography). Errors in the conversion from x-ray Hounsfield units (HU) to proton relative stopping powers (RSP) leads to errors in the predicted proton range. To account for the errors, 3.5% margins are included in the treatment plan. This means …

Goal Programming Approach For Bi-Objective Optimization For A Single Batch Processing Machine, Dheeban Kumar Srinivasan Sampathi

Graduate Research Theses & Dissertations

This research considers a real-time problem where jobs need to be batched and scheduled to a single batch processing machine to minimize makespan and maximum tardiness. Jobs must be placed in batches such that the machine capacity is not violated. The jobs considered have unequal ready times, unequal processing times, and unequal sizes. This research aims to develop an effective solution approach for the proposed problem. The problem under study can be denoted as 1|p-batch, sj, rj| Cmax, Tmax.

The problem under study is NP-Hard. A new Mixed Integer Linear Programming (MILP) formulation using Goal programming (MILP-G) and Column Generation …

Particle Swarm Optimization And Ant Colony Optimization For Bi-Objective Optimization For A Single Batch Processing Machine, Sajith Gopinathan

Graduate Research Theses & Dissertations

This research studies the scheduling of jobs with unequal ready times, unequal processing times, and unequal sizes on a single batch processing machine, with the objectives of minimizing makespan and maximum tardiness. For the batch process, the jobs are required to be grouped into batches and further these batches are scheduled on the machine to minimize the objectives, without violating the machine capacity. The problem under study can be denoted as 1|p-batch, sj, rj| Cmax,Tmax in the standard three-field notation. A thorough review of literature pertinent to the field of research has been conducted and two new approaches have been …

Investigation Of Spontaneously Patterned Nanoporous Organosilicate Thin Film Channels For Liquid Chromatography Applications., Ashwin Sanjay Bhaskaran

Graduate Research Theses & Dissertations

Microscale devices are attractive options for the advancement of biomedical engineering and life science. They have huge potential in the pharmaceutical and biomedical fields provided the critical factors such as device size, product purity and efficiency are not a hindrance. In most cases, traditional microelectronics fabrication processes are quite costly and complicated. By improving on them, their application in fields such as chemical sensing, detection and analysis is possible. By implementing this on a chip, we can reduce the cost and improve portability. This thesis focuses on the investigation of a novel class of spontaneously patterned nanoporous organosilicate nanoparticle-based films …

Warm Unit Rod Movement Stand For Proton Improvement Project Ii, Christopher Shohei Becker

Graduate Research Theses & Dissertations

Fermilab is responsible for many experiments involving proton acceleration and requires a significant upgrade to its linear accelerator infrastructure to meet the needs of the 21st century high energy physics. The Proton Improvement Project II (PIP II) is a plan to allow Fermilab to maintain its title of most intense accelerator by doubling the output of its proton beam to 800 MeV. An array of high frequency cryomodules generate the beam but are limited in total manufacturing lengths. To connect the multiple devices, a combination of magnets and ion vacuum pumps at room temperature -- therefore called warm units -- …