Engineering Commons^™

Optimal Recovery Trajectories For Automatic Ground Collision Avoidance Systems (Auto Gcas), Angela W. Suplisson

Theses and Dissertations

The USAF's F-16 Automatic Ground Collision Avoidance System (Auto GCAS) uses a single pre-planned roll to wings- level and 5-g pull-up to meet the operational requirements of being both aggressive and timely, meaning that extremely agile avoidance maneuvers will be executed at the last second to avoid the ground. There currently exists no similar Auto GCAS for manned military heavy' aircraft with lower climb performance such as transport, tanker, or bomber aircraft. This research proposes a new optimal control approach to the ground collision avoidance problem for heavy aircraft by mapping the aggressive and timely requirements of the automatic recovery …

Experimental Magnetohydrodynamic Energy Extraction From A Pulsed Detonation, Kaz I. Teope

Theses and Dissertations

The high MWatt power available in a fuel-fed detonation wave, which contains combustion ions in the trailing gas, provides an opportunity for external power extraction via electromagnetically forced charged particle drift. Sets of experiments were accomplished using a pulsed detonation tube, extracting power across a load resistor in an electrical circuit with an applied electric or magnetic field to determine what magnitude of gas conductivity and power extraction could be attained from an unseeded or seeded pulsed detonation driven combustion. Due to the low magnetic field strength, even with flow seeding, the power extracted in this research was not enough …

Fatigue Behavior Of Im7/Bmi 5250-4 Composite At Room And Elevated Temperatures, James T. Tipton

Theses and Dissertations

The tension-tension fatigue and tension-compression fatigue behaviors of the IM7/BMI 5250-4 composite were investigated. The tension-tension fatigue of the composite with 0/90 and ±45 fiber orientations was studied at 23, 170, and 190°C. The tension-compression fatigue of the composite with 0/90 fiber orientation was examined at 23°C. The tensile and compressive properties of the composite were also evaluated at room and elevated temperatures for both 0/90 and ±45 fiber orientations. Elevated temperature had little effect on the tensile properties of the 0/90 fiber orientation, but strongly influenced the ±45 tensile properties as well as the compressive properties of both fiber …

Mechanical Testing Of Ultra-High Temperature Ceramics At 1500°C In Air -Development Of An Experimental Facility And Test Method, Sheena L. Winder

Theses and Dissertations

With a melting point in excess of 3000°C and a high density, ultra-high temperature ceramics (UHTCs) are a candidate material for hypersonic flight vehicles, atmospheric re-entry vehicles, and rocket propulsion systems. When ceramics are under consideration as a structural material, creep is an important design criterion and a life-limiting condition. However, the characterization of mechanical behavior at temperatures in excess of 1300°C has many challenges to overcome. Of utmost importance is the selection of materials for test fixtures. Materials selected must maintain their structural integrity, not cause chemical degradation of the test material, and not interfere with the acquisition of …

Load Frequency Control Of Battery Based Energy Storages, Neeru Saini

Theses and Dissertations

This work is the study of potential applications of battery-based energy storages in the power system so that the performance can be improved. The research is focused on the case where batteries are installed at the load side. Such a battery works like an energy buffer between power system and a load. It is possible to control the battery charging time based on the status of the power system operation and the state of charger of the battery so that the power flow in the power system can become more stable. The strategy of load frequency control (LFC) was investigated …

Raman Spectroscopy As A Tool For Single Circulating Tumor Cell (Ctc) Detection And Imaging, Zeid A. Nima

Theses and Dissertations

Breast cancer is the most common type of cancers in the United States. It is imperative that a quick and reliable method for the early detection of circulating tumor cells (CTCs) be identified and tested. In this research several new detection and imaging techniques based on using Raman spectroscopy have been invented. Raman active nano-complex agents based on single-walled carbon nanotubes (SWCNTs) were prepared and used for the swift and specific detection of breast cancer cells. SWCNTs are functionalized with the anti-epithelial cell adhesion molecule (anti-EpCAM) antibody, were able to detect CTCs within 30 min and discriminate few CTCs among …

A Ten-Year Search For Synchronous Cells: Obstacles, Solutions, And Practical Applications, Charles E. Helmstetter

Biomedical Engineering and Sciences Faculty Publications

My effort to use synchronously dividing cultures to examine the Escherichia coli cell cycle involved a 10-year struggle with failure after failure punctuated by a few gratifying successes, especially at the end. In this essay, I recount my personal journey in this obsessive experimental pursuit. That narrative is followed by a description of a simplified version of the "baby machine," a technique that was developed to obtain minimally disturbed, synchronously growing E. coli cells. Subsequent studies with this methodology led to an understanding of the basic properties of the relationship between chromosome replication and cell division. Accordingly, I end this …

Vortex Identification In The Wake Of A Wind Turbine Array, Aleksandr Sergeyevich Aseyev

Dissertations and Theses

Vortex identification techniques are used to analyze the flow structure in a 4 x 3 array of scale model wind turbines. Q-criterion, Δ-criterion, and λ₂-criterion are applied to Particle Image Velocimetry data gathered fore and aft of the last row centerline turbine. Q-criterion and λ₂-criterion provide a clear indication of regions where vortical activity exists while the Δ-criterion does not. Galilean decomposition, Reynolds decomposition, vorticity, and swirling strength are used to further understand the location and behavior of the vortices. The techniques identify and display the high magnitude vortices in high shear zones resulting from the …

Quantiifying Stormwater Runoff Contaminant Mitigation By Bioretention Cells, Patrick J. Walsh

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

This research study has three objectives, quantify the presence and concentration of selected contaminants in urban stormwater runoff from several urban locations within Lincoln, Nebraska, quantify the effectiveness of two, 10-year old bioretention cells, for reducing concentrations of contaminants in effluent and quantify the effectiveness of six rain gardens.

The primary research sites were two bioretention cells using automated samplers collecting grab samples of stormwater runoff influent and effluent for at least six precipitation events during a two-year period. Additional research sites included samplers for two rainfall, six rain garden, two commercial rooftop, two commercial parking lot, and six residential …

Black Bear Parathyroid Hormone And Methods Of Using Black Bear Parathyroid Hormone, Seth W. Donahue

Michigan Tech Patents

Black bear parathyroid hormone (PTH) and functional fragments thereof are provided. Also provided are methods of using black bear PTH and functional fragments for increasing cAMP in a bone-forming cell; reducing apoptosis in a bone-forming cell; decreasing the ratio of expression levels of Bax protein to Bcl-2 protein in a bone-forming cell; increasing the expression level of one or more of a bone matrix protein, a transcriptional activator, or a transcriptional regulator in a bone-forming cell; enhancing bone mineral density, increasing bone mass, decreasing bone loss, or reducing the incidence of bone fractures, or any combination thereof, in a subject; …

Structure-Thermodynamics-Antioxidant Activity Relationships Of Selected Natural Phenolic Acids And Derivatives: An Experimental And Theoretical Evaluation, Yuzhen Chen, Huizhi Xiao, Jie Zheng

Chemical, Biomolecular, and Corrosion Engineering Faculty Research

Phenolic acids and derivatives have potential biological functions, however, little is known about the structure-activity relationships and the underlying action mechanisms of these phenolic acids to date. Herein we investigate the structure-thermodynamics-antioxidant relationships of 20 natural phenolic acids and derivatives using DPPH^• scavenging assay, density functional theory calculations at the B3LYP/6-311++G(d,p) levels of theory, and quantitative structure-activity relationship (QSAR) modeling. Three main working mechanisms (HAT, SETPT and SPLET) are explored in four micro-environments (gas-phase, benzene, water and ethanol). Computed thermodynamics parameters (BDE, IP, PDE, PA and ETE) are compared with the experimental radical scavenging activities against DPPH^•. …

College Of Engineering News, Georgia Southern University

College of Engineering & Computing: News & Publications (2010-2023)

• Brandon Kimmons to Present Research at the American Chemical Society National Meeting

Information Technology News, Georgia Southern University

Information Technology: News & Publications (2012-2023)

• Brandon Kimmons to Present Research at the American Chemical Society National Meeting

Student Professional Awareness Conference - Additional Details | Electrical And Computer Engineering, Usu College Of Engineering

College of Engineering News

LOGAN, Utah – March 16, 2015 – The USU local chapter of IEEE, institute of electrical and electronics engineers, will have the privilege of hosting the annual StudentProfessional Awareness conference, SPAC 2015, on March 28, 2015.

Simpel: Circuit Model For Photonic Spike Processing Laser Neurons., Bhavin J Shastri, Mitchell A Nahmias, Alexander N Tait, Ben Wu, Paul R Prucnal

Henry M. Rowan College of Engineering Departmental Research

We propose an equivalent circuit model for photonic spike processing laser neurons with an embedded saturable absorber—a simulation model for photonic excitable lasers (SIMPEL). We show that by mapping the laser neuron rate equations into a circuit model, SPICE analysis can be used as an efficient and accurate engine for numerical calculations, capable of generalization to a variety of different types of laser neurons with saturable absorber found in literature. The development of this model parallels the Hodgkin-Huxley model of neuron biophysics, a circuit framework which brought efficiency, modularity, and generalizability to the study of neural dynamics. We employ the …

The Application Of Biomedical Engineering Techniques To The Diagnosis And Management Of Tropical Diseases: A Review, Fatimah Ibrahim, Tzer Hwai Gilbert Thio, Tarig Faisal, Michael Neuman

Michigan Tech Publications, Part 1

This paper reviews a number of biomedical engineering approaches to help aid in the detection and treatment of tropical diseases such as dengue, malaria, cholera, schistosomiasis, lymphatic filariasis, ebola, leprosy, leishmaniasis, and American trypanosomiasis (Chagas). Many different forms of non-invasive approaches such as ultrasound, echocardiography and electrocardiography, bioelectrical impedance, optical detection, simplified and rapid serological tests such as lab-on-chip and micro-/nano-fluidic platforms and medical support systems such as artificial intelligence clinical support systems are discussed. The paper also reviewed the novel clinical diagnosis and management systems using artificial intelligence and bioelectrical impedance techniques for dengue clinical applications.

Stochastic Assessment Of Bone Fragility In Human Lumbar Spine, Rajeshwar Rao Pinninti

Electrical Engineering Theses

Osteoporotic fractures are a vital public health concern and create a great economic burden for our society. It is estimated that more than 2 million fractures occur in the United States at a cost of $17 billion each year. Deterioration of microarchitecture of trabecular bone is considered as a major contributor to bone fragility. Current clinical imaging modalities such as Dual-energy X-ray absorptiometry (DXA) are not able to describe bone microarchitecture due to their low resolution. The main objective of this study was to obtain the relationship between stochastic parameters calculated from bone mineral density (BMD) maps of DXA scans …

Modeling And Simulation Of Evacuation Plan For Hancock Stadium, Nirmal Neranjan Weerasekara

Theses and Dissertations

The goal of this study is to use Modeling and Simulation of Evacuation Plan (MSEP) to support management to execute proper evacuation plan in case of emergency at Hancock Stadium in Illinois State University. Analyses of the research literature and evacuation scenarios are used to build a simulation system that will connect a description of emergency and evacuation situation with its context. It shows how an evacuation plan actually functions. The results of the study will help safety managers to understand the current situations of evacuation according to the specific simulation scenarios. The evacuation simulation is categorized according to the …

Adhesion Of Germanium Electrode On Nickel Substrate For Lithium Ion Battery Applications, Aadithya Jeyaranjan

USF Tampa Graduate Theses and Dissertations

Lithium ion batteries (LIBs) have gained increasing popularity due to their high potential, low self-discharge, zero priming and minimal memory effect. However, the emergence of electrical vehicles and hybrid electrical vehicles in the automobile industry, where LIBs are predominantly in use, instilled a need to improve LIB batteries by experimenting with new materials. Graphite, the commonly used anode material for LIBs suffers from low theoretical capacity (372 mA h g-1) and torpid rate performance. Germanium (Ge) seems to be a promising substitute of carbon due to its high theoretical capacity, high Li+ diffusivity and electrical conductivity. However, Ge undergoes large …

An Experimental Study On Passive Dynamic Walking, Philip Andrew Hatzitheodorou

USF Tampa Graduate Theses and Dissertations

In this study, a previously designed passive dynamic walker (PDW) is built out of aluminum and plastic. The aim of the study was to produce an asymmetrical PDW and to compare the results to a computer simulation to validate the mathematical model. It also aimed at identifying the limitations of using additive manufacturing to create components for a PDW as well as gain insights on asymmetric systems.

Beginning with a five mass kneed model, parameters were varied to produce up to a nine mass kneed model solution. The nine mass model allows more variability in added mass locations and separates …

Identification Of Employee Engagement Practices Viewed As Critical To Retention: A Cross-Generational Comparison, Sharon R. Floyd

Dissertations

Purpose. The purpose of this study was to identify the employee engagement practices that millennial IT workers perceive as important to retention. The secondary purpose of the study was to determine whether a difference exists between the engagement practices that appeal to millennial IT workers and the engagement practices that appeal to remaining IT working groups, which include the baby boomers and generation X.

Methodology. A quantitative, descriptive, survey-based research method was chosen for this study. The population included information technology workers representing three generations of working adults, including baby boomers, generation Xers, and millennials. The sample included technology workers …

Low-Power And Robust Level-Shifter With Contention Mitigation For Memory And Standalone Applications, Kenneth M. Ramclam

USF Tampa Graduate Theses and Dissertations

The scaling down of transistor sizes has imposed significant challenges in today's technology. Memories such as eDRAM, are experiencing poor retention time because of challenges such as reference voltage variation, high transistor leakage, and low cell capacitance. It can be seen that we must consider not only the first order effects, but also the second order effects to ensure we keep up with current technology trends such as Moore's law. In this thesis we explore various circuit level techniques on level shifters in order to achieve better retention time. With our research, we have addressed important design challenges and propose …

On The Selection Of Just-In-Time Interventions, Luis Gabriel Jaimes

USF Tampa Graduate Theses and Dissertations

A deeper understanding of human physiology, combined with improvements in sensing technologies, is fulfilling the vision of affective computing, where applications monitor and react to changes in affect. Further, the proliferation of commodity mobile devices is extending these applications into the natural environment, where they become a pervasive part of our daily lives. This work examines one such pervasive affective computing application with significant implications for long-term health and quality of life adaptive just-in-time interventions (AJITIs). We discuss fundamental components needed to design AJITIs based for one kind of affective data, namely stress. Chronic stress has significant long-term behavioral and …

Plastic Deformation Of A Model Glass Induced By A Local Shear Transformation, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

The effect of a local shear transformation on plastic deformation of a three-dimensional amorphous solid is studied using molecular dynamics simulations. We consider a spherical inclusion, which is gradually transformed into an ellipsoid of the same volume and then converted back into the sphere. It is shown that at sufficiently large strain amplitudes, the deformation of the material involves localized plastic events that are identified based on the relative displacement of atoms before and after the shear transformation. We find that the density profiles of cage jumps decay away from the inclusion, which correlates well with the radial dependence of …

Performance Metrics For Depth-Based Signal Separation Using Deep Vertical Line Arrays, John K. Boyle

Dissertations and Theses

Vertical line arrays (VLAs) deployed below the critical depth in the deep ocean can exploit reliable acoustic path (RAP) propagation, which provides low transmission loss (TL) for targets at moderate ranges, and increased TL for distant interferers. However, sound from nearby surface interferers also undergoes RAP propagation, and without horizontal aperture, a VLA cannot separate these interferers from submerged targets. A recent publication by McCargar and Zurk (2013) addressed this issue, presenting a transform-based method for passive, depth-based separation of signals received on deep VLAs based on the depth-dependent modulation caused by the interference between the direct and surface-reflected acoustic …

Structural Patterns At All Scales In A Nonmetallic Chiral Au_133(Sr)_52 Nanoparticle, Chenjie Zeng, Yuxiang Chen, Kristin Kirschbaum, Kannatassen Appavoo, Matthew Y. Sfeir, Rongchao Jin

Publications and Research

Structural ordering is widely present in molecules and materials. However, the organization of molecules on the curved surface of nanoparticles is still the least understood owing to the major limitations of the current surface characterization tools. By the merits of x-ray crystallography, we reveal the structural ordering at all scales in a super robust 133–gold atom nanoparticle protected by 52 thiolate ligands, which is manifested in self-assembled hierarchical patterns starting from the metal core to the interfacial –S–Au–S– ladder-like helical “stripes” and further to the “swirls” of carbon tails. These complex surface patterns have not been observed in the smaller …

Risk-Taking Characteristics As Explanatory Variables In Variations Of Fatality Rates In The Southeastern United States, Jodi Anne Godfrey

USF Tampa Graduate Theses and Dissertations

Traffic fatalities accounted for 1.24 million lives lost in 2013 worldwide, and almost 33 thousand of those fatalities were in the U.S. in 2013. The southeastern region of the nation stands out for continuously having higher fatality rates per mile driven than the national average. If one can establish compelling relationships between various factors and fatality rates, then policies and investments can be targeted to increase the safety on the network by focusing on policies that mitigate those factors. In this research effort risk-taking characteristics are explored. These factors have not been as comprehensively reviewed as conventional factors such as …

Microfracture And Surfactant Impact On Linear Cocurrent Brine Imbibition In Gas-Saturated Shale, Yongpeng Sun, Baojun Bai, Mingzhen Wei

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

During and after hydraulic fracturing, fluid-shale interaction has a prominent impact on liquid retention and thus on gas phase permeability and gas productivity. By providing a low surface tension or wettability alteration, surfactants are widely used to decrease liquid retention after fracturing. To evaluate the liquid intake of a rock sample, an imbibition experiment is commonly used, especially when it is treated by a surfactant. However, conventional imbibition experiments with gas shale could not quantitate the imbibition behaviors as it does with conventional rocks because of the low porosity and extremely low permeability of gas shale. In this paper, a …

Effects Of Magnetic Nanoparticles And External Magnetostatic Field On The Bulk Heterojunction Polymer Solar Cells, Kai Wang, Chao Yi, Chang Liu, Xiaowen Hu, Steven Chuang, Xiong Gong

Polymer Science Faculty Research

The price of energy to separate tightly bound electron-hole pair (or charge-transfer state) and extract freely movable charges from low-mobility materials represents fundamental losses for many low-cost photovoltaic devices. In bulk heterojunction (BHJ) polymer solar cells (PSCs), approximately 50% of the total efficiency lost among all energy loss pathways is due to the photogenerated charge carrier recombination within PSCs and low charge carrier mobility of disordered organic materials. To address these issues, we introduce magnetic nanoparticles (MNPs) and orientate these MNPS within BHJ composite by an external magnetostatic field. Over 50% enhanced efficiency was observed from BHJ PSCs incorporated with …

The Women Airforce Service Pilots (Wasp) Of World War Ii, Natalie J. Stewart-Smith

ERAU Prescott Aviation History Program

Hear the fascinating story of the women who flew in WW II as members of the WASP, from Natalie Stewart-Smith. Her thesis on them was the very first academic study of the WASP and is based on numerous personal interviews, including Jacqueline Cochran, their founder. The military contribution of women fliers during World War I is a seldom seen part of the WASP story as well.