Engineering Commons^™

Automatic Food Expiration Notification System, Nikolas-Viktor P. Doukas, Ozan Celebi, Lindsey E. Colgrove, Michael D. Werner, Tre Commings, Christopher M. Zatek, Daniel E. Odihi

Engagement & Service-Learning Summit

No abstract provided.

Community-Scale Water Treatment Systems In The Dominican Republic, Water Supply In The Dr

Engagement & Service-Learning Summit

No abstract provided.

"Smart" Airport App, Jacob A. Collins, Alyssa Williams, Vikrant Neb, Pranav Gupta

Engagement & Service-Learning Summit

We are going to make an app that can be used by people traveling through or from ORD airport (Chicago), which will provide live time update for security check line (in terms of time), change of gate for the flight and whether or not the flight is on time. The reason for developing this application is to simplify and improve the passenger’s overall airport experience in order to make it more enjoyable, informative, and time efficient while decreasing the current negative mentality towards traveling. Resources needed to create the prototype would include softwares that help in creating wireframes of the …

Prada: Combating Voltage Noise In The Noc Power Supply Through Flow-Control And Routing Algorithms., Prabal Basu, Rajesh Jayashankarashridevi, Koushik Chakraborty, Sanghamitra Roy

Electrical and Computer Engineering Faculty Publications

Network-on-Chip (NoC) has become the de-facto standard for on-chip communication in MPSoCs. The growing NoC power footprint, increase in the transistor current, and high switching speed of the logic devices, exacerbate the peak power supply noise (PSN) in the NoC power delivery network (PDN). Hence, preserving power supply integrity in the NoC PDN is critical. In this work, we propose PRADA (PSN-aware Runtime Adaptation)-a collection of a novel flow-control protocol (PAF) and an adaptive routing algorithm (PAR), to mitigate PSN in NoCs. Our best scheme achieves 14% and 12% improvements in the regional peak PSN and energy efficiency, with an …

Ultrasonic Data Transmission And Steganography, Hunter Young

KSU Journey Honors College Capstones and Theses

This project discusses the feasibility of using ultrasound to transmit data between computer systems, particularly computer systems that have been intentionally cut off from traditional networks for increased security. The goal of this project is to provide a synthesis of the current research that has been done into the use of ultrasonic data transmission, and to conduct a series of tests determining the validity of certain claims made in regards to ultrasonic data transmission within the information security community. All research, experiments, results, and inferences have been discussed in the context of how they relate to the realm of information …

Selective Enhancement Of Macropinocytosis For The Treatment Of Non-Small Cell Lung Cancer, Raul Iglesias

USF Tampa Graduate Theses and Dissertations

Over the past few years, researchers have focused their attention on the development of targeted cancer therapies to minimize the side effects associated with non-targeted treatments such as chemotherapy. Specifically, these approaches have focused on blocking growth factor receptors (GFR) that are overexpressed in cancer cells. In this thesis, we also focus on targeting overexpressed GFR; however, instead of blocking the GFR, our novel approach aims at using them to selectively enhance the endocytotic process of macropinocytosis to deliver peptides that either disrupts the mitochondria or inhibits glycolysis.

Herein, we show the selective enhancement of macropinocytosis by the fusion protein …

Controlled Microfluidics To Examine Growth-Factor Induced Migration Of Neural Progenitors In The Drosophila Visual System, Cade Beck, Tanya Singh, Angela Farooqi, Tadmiri Venkatesh, Maribel Vazquez

Publications and Research

BACKGROUND:

The developing visual system in Drosophila melanogaster provides an excellent model with which to examine the effects of changing microenvironments on neural cell migration via microfluidics, because the combined experimental system enables direct genetic manipulation, in vivo observation, and in vitro imaging of cells, post-embryo. Exogenous signaling from ligands such as fibroblast growth factor (FGF) is well-known to control glia differentiation, cell migration, and axonal wrapping central to vision.

NEW METHOD:

The current study employs a microfluidic device to examine how controlled concentration gradient fields of FGF are able to regulate the migration of vision-critical glia cells with and …

Spark Plasma Sintering: From The Thermal Gradient To Advanced Ceramic Composites, Dmytro Demirskyi

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

It is well recognized that spark plasma sintering (SPS) is one of the most popular consolidation methods used to produce metal, ceramics and their composites. The better properties of the materials consolidated using SPS is usually attributed to: (i) shorter processing cycle and (ii) lower processing temperature. Hence, it is sometimes debated that there is a specific role of pulsed electric current or local thermal gradient which affect the consolidation process during SPS by changing mass-transport mechanism or local phase composition.

This work summarizes some model experiments on the initial and final stages of SPS consolidation process to verify possible …

Features Of Grain Growth And Grain Boundary Formation Under Microwave And Spark Plasma Sintering Conditions, Ostap Zgalat, Andrey Ragulya

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The feedback properties of particulate nanomaterials versus their structure parameters (grain size, pore size), were found much more sensitive than that in conventional materials [1-3]. Among them field assisted sintering techniques including SPS and microwave sintering (MWS) were intensively developed [4-9]. The effect of inhibited grains growth for nanomaterials was established for Field Assisted Sintering Technology [4,5,8,9].

The FAST or Spark Plasma Sintering (SPS) is a rapid rate consolidation technology where effect of electromagnetic field enhanced by external pressure. The studies of FAST densification for nano-TiN shows the possibility to substantially inhibit the grain growth and fabricate materials with grains …

Modelling And Fem Simulation Of Electric Field Assisted Sintering Of Tungsten Carbide (Wc), Sree Koundinya

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Numerical modeling of sintering and its process variants (such as Hot Pressing, Hot Isostatic Pressing (HIP), Field Assisted Sintering Technique (FAST) or Spark Plasma Sintering (SPS), etc.) has been a field of interest among researchers and industrialists due to its efficiency in predicting various sintering characteristics such as densification, volumetric and shape changes. Thus, various mathematical models have been developed over the years, where, earlier models for sintering included rheological investigations which were able to capture the macroscopic shape and volume changes of a porous body over the process of sintering and were known as phenomenological models [1]. Due to …

Densification Of Dense Nano Crystalline Zinc Oxide Under Electric Field, Olivier Guillon

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The retention of nanocrystallinity in dense ceramics is still a challenge, even with the application of stress-assisted methods like Spark Plasma Sintering. The effect of bound water combined with high heating rates seems to significantly promote the densification of zinc oxide nanoparticles. Hence, dense nano-grained ZnO could be synthesized at a temperature of only 400 °C with minimal grain growth. Microstructural analysis as well as chemical and spectroscopic methods can help identify the mechanisms involved in this peculiar behavior. The direct effect of electric field seems to be in these conditions negligible. Nevertheless, the sintering behavior can be also modified …

Application Of Microwave Energy To Consolidate Titanium Powder, R. Sadangi

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Titanium (Ti) has many attractive attributes for military, industrial, and aerospace applications including high specific strength, no magnetic signature, and excellent corrosion resistance. However, its use has been limited by high processing costs. Powder metallurgy is a cost effective way to fabricate high-quality, near-net-shape products. Consolidation of titanium powder compacts is performed in vacuum furnace and the overall processing cycle times can vary from hours to days. Microwave sintering of titanium is a recent development in powder metallurgy of titanium. Microwave sintering is energy efficient compared to conventional sintering methods due to direct microwave heating of the titanium powder compacts …

Fast One-Step Synthesis And Sintering Of Materials Promoted By Electric Fields, Lilian Menezes

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

CaCu₃Ti₄O₁₂ (CCTO) has attracted great attention because of its potential application in microelectronic devices, as showing very high ɛ′ values (~ 12,000) with good stability from room temperature to 300 °C [1]. This material is usually prepared through conventional synthesis (solid-state reaction) at 1000 °C followed by sintering at 1100 °C, for dwell times of several hours. These high annealing temperatures and times lead to ceramics with micro-sized grains, exceeding significantly 1.0 µm in most cases. Field-assisted flash sintering [2] was here considered for producing high-quality CCTO electroceramics, from a powder originally synthesized via …

Modification Of The Interdiffusion Process In The Fe–Al System By Sps And Field Assisted Sintering, Hanka Becker

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Utilizing the Spark Plasma Sintering (SPS) / Field Assisted Sintering Technology in electrically conductive samples, the pulsed direct current (DC) induces primarily Joule heating. Nevertheless, the applied DC is frequently reported to accelerate diffusion processes as compared with the conventional heating in a furnace [1]. Thereby, after SPS treatment, the microstructural evolution is changed against the conventional heat treatment even if the diffusion processes run at the same temperature [2]. These differences are attributed to various phenomena, whose characteristic significance depends on the material system. The present study of the reactive diffusion in the binary system Al-Fe aims at contributing …

Self-Organized Structure In Current-Activated Pressure-Assisted Densification (Capad), Sebastian Angst

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Using nanostructured thermoelectrics led to a significant improvement of the figure of merit. An easily upscalable and cheap way of producing nanostructured bulk material is current-activated pressure-assisted densification (CAPAD). This process is quite complex and it has been shown that the powder morphology gives a feedback to the process itself [1,2]. We investigated the influence of particle properties of binary mixtures on the evolving structure. For this purpose we use a network model [3] based on the Onsager-de Groot-Callen theory. In the simulations we find that depending on the difference between the Seebeck coefficients of both materials either a well …

Observations On Flash Sintering Of Uranium Dioxide, Kenneth Mcclellan

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The recent prioritization on development of nuclear fuels with enhanced accident tolerance has led the community to consider fuel systems that offer improvements in certain performance characteristics such as fission gas retention, oxidation resistance and thermal conduction. Advanced fuels being studied for enhanced accident tolerance often have unique characteristics that make conventional sintering routes undesirable for or incapable of yielding the required fuel pellet characteristics. For illustration, UO₂-composite fuels with second phases for increased thermal conductivity, such as SiC, can have deleterious reactions with the UO₂ fuel above operating temperatures but below temperatures required to sinter a …

Flash Sintering Of Srtio3, Fabian Lemke

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Since the first reports of flash sintering in 2010 the community is continuously growing. Several parameters have been identified to be important gaining access to flash sintering, e.g. the temperature change due to joule heating, changes in the microstructure, polarization of defects or other effects on the defect chemistry. Analyzing the process is raised to another level of complexity compared to conventional sintering.

Sintering and grain growth experiments under an electrical field are conducted with SrTiO3. The results are compared to our existing database, implying simulations of the defect-chemistry, to discriminate the most important parameters in the flash sintering process. …

Abnormal Grain Growth In Pressure Assisted Sintering Of Bala4ti4o15, Ana Senos

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The application of compressive stresses during sintering is known to be an efficient way to eliminate porosity at lower temperatures by the direct positive effect on the sintering driving force. Therefore, it is the basis of some special sintering techniques, such as: Hot pressing (HP), Hot isostatic pressing (HIP), Hot forging (HF) and, together with the electric field, in the Electric field assisted sintering (EFAS). Despite the fact that the role of applied stress on the densification is well established, its effect on the movement of grain boundaries (GBs) for grain growth in 2D/3D ceramics has not been sufficiently addressed …

Fabrication Of A Vitreous Porcelain By Conventional Sintering And Spark Plasma Sintering, Wirat Lerdprom

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

A vitreous porcelain body was fabricated by a conventional sintering and spark plasma sintering (SPS). The effects of sintering parameters such as heating rate, dwell time, temperature, and pressure were investigated. The porcelain sintered using the SPS techniques attained higher apparent bulk density of 2.52 g/cm³ compared with a conventionally sintered porcelain, which is 2.39 g/cm³, however, both of them exhibited similar water absorption of 0.01%. The SPS sintered porcelain presented a dense microstructure, which cannot be seen in conventionally sintered porcelain products. Mineralogically, the SPS sintered porcelain contained residual albite, quartz, mullite and glass while the …

Fast Sintering Of Alumina, Spinel And Yttria-Stabilized Zirconia Three-Phase Composites, David Kok

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Field assisted sintering experiments in air were carried out on multiphase ceramics composed of Al₂O₃, MgAl₂O₄ and cubic 8 mol% Y₂O₃ stabilized ZrO₂ (8YSZ) to investigate the grain boundary interactions as well as the sintering outcomes of an applied electric field. The ultimate goal is to develop a method to produce a dense nanocrystalline multiphase oxide ceramic for energy applications in extreme environments, without exposing the material to carbon contamination or a reducing atmosphere as is common in “spark plasma sintering” (SPS). Experiments were carried out in a modified …

Growth Behavior Of Faceted Na1/2bi1/2tio3-Batio3 Grains In Single And Two-Step Sintering In Support For The Microstructural Evolution Principle, Seok Ko

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

We investigated the grain growth behavior in 89Na_1/2Bi_1/2TiO₃-11BaTiO₃ (mol %, NBT-11BT) at 1100 and 1200 °C, and also under two-step sintering at 1200 (first) and 1100 °C (second). When the powder compacts were sintered at 1100 and 1200 °C, the initial growth behavior was quite normal; however, the subsequent growth behavior was distinctively abnormal and moderately abnormal, respectively. This difference in growth behavior is attributed to a change in the critical driving force for appreciable migration of the boundary with temperature and can be explained by the coupling effect of the maximum driving …

Microstructure And Mechanical Properties Of Spark Plasma Sintered Tungsten-Copper– Zinc Composites, Thabiso Langa, S. Diouf

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Tungsten/Copper (W/Cu) composites, generally used for applications whereby the combination of high heat resistance, high electrical and thermal conductivity and low thermal expansion is required, are suitable for hard working conditions such as intensive electrical sparks, gouging spark erosion, surface melting, welding, material transfer etc. However, the large disparity between the melting point of tungsten (3410 °C) and that of copper (1083 °C) make their production through traditional processes very difficult. Furthermore the difficulty of approaching near theoretical densities even by using liquid phase sintering, due to the negligible mutual solubility of the constituents and high wetting angle of liquid …

Application Of Steel As An Alternative Tool Material For Field Assisted Sintering In Spa, Alexander Laptev

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The Field Assisted Sintering Technique/Spark Plasma Sintering (FAST/SPS) is a new method for fast processing of variety metallic and ceramic materials with unique microstructure frequently far from equilibrium. Despite an essential progress in fundamental understanding and in upscaling of this technique from laboratory to industrial scale, some challenges are still remaining. One of them is application of a tool made from material other then traditionally used graphite. The advantages of graphite are high electrical conductivity, low temperature dependence of strength and good machinability. At the same time, the strength of graphite is relatively low. This property restricts the pressure used …

Flash Sintering Of Tcp Bioceramics: Effect Of Particle Size And Influence On Β→Α Transition, Matteo Frasnelli

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

In this work, sintering behavior of tricalcium phosphate ceramics under the effect of an external electrical field (in Flash sintering configuration) was analyzed to obtain dense bio-resorbable components. The aim was to understand whether the application of the external E-field, which allows to reduce drastically sintering time and temperature, limits also the undesired β→α-TCP phase transition.

TCP powders were synthesized by solid state reaction and by wet synthesis though precipitation from aqueous solutions, this allowing to obtain amorphous calcium phosphate nano-particles, which were crystallized into nano β-TCP by thermal treatment. Then, cold-pressed green pellets were prepared and their sintering behavior …

The Design Of A Simple, Spiking Sparse Coding Algorithm For Memristive Hardware, Walt Woods

Dissertations and Theses

Calculating a sparse code for signals with high dimensionality, such as high-resolution images, takes substantial time to compute on a traditional computer architecture. Memristors present the opportunity to combine storage and computing elements into a single, compact device, drastically reducing the area required to perform these calculations. This work focused on the analysis of two existing sparse coding architectures, one of which utilizes memristors, as well as the design of a new, third architecture that employs a memristive crossbar. These architectures implement either a non-spiking or spiking variety of sparse coding based on the Locally Competitive Algorithm (LCA) introduced by …

Acid-Base Equilibria In Organic-Solvent/Water Mixtures And Their Relevance To Gas/Particle Partitioning In The Atmosphere And In Tobacco Smoke, Julia Lynn Degagne

Dissertations and Theses

Acid-base equilibria in organic particulate matter (PM) are poorly understood, but have important implications for air quality and public health. First, acid-base reactions in organic particulate matter affect the gas/particle partitioning of organic compounds in the atmosphere, and these processes are not currently represented in atmospheric and climate change models. Second, the acid-base balance of tobacco smoke affects the amount of nicotine absorbed by the smoker, and a greater understanding of this balance would help to relate cigarette smoke composition to the addictive properties of cigarettes. This work presents data related to both air quality and tobacco smoke modeling.

The …

Hyperloop Dream Team: Students Represent At Spacex Challenge At Texas A&M, Becky St. Clair

Andrews Agenda: Campus News

No abstract provided.

Sustainable Drainage Systems: Helping People Live With Water, Glyn Everett, Jessica Lamond, Anita T. Morzillo, Faith Ka Shun Chan, Annie Marissa Matsler

Urban Studies and Planning Faculty Publications and Presentations

Sustainable drainage systems or ‘Suds’ are increasingly accepted as an effective means of ‘making space for water’, adapting to possible climate change and helping communities become more flood and drought resilient. This study explores potential shifts in perception and attitude through Suds installation, development and habituation. Attitudes and awareness in communities in the USA and UK, where Suds have been in place for some time, were compared and contrasted, examining any evolution of beliefs and practices and wider community resilience. The principal finding was that there existed a lack of understanding about the existence and function of Suds. The paper …

Kayapo Media Making: Building On-Site Capacity, Kaitlin Harris

Engagement & Service-Learning Summit

No abstract provided.

Processing High Strength Low Oxide And Metal Impurity Zrb2 Ceramics Using Boron Carbide And Spark Plasma Sintering, Erica Corral

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Zirconium diboride is an ultra-high temperature ceramic (UHTC) with attractive material properties for use in extreme hypersonic flight environments and energy applications. The diboride phase is the basis for high temperature oxidation resistant UHTC composites using secondary phase reinforcements that also enhance high temperature properties of ZrB₂-based composites. However, the mechanical properties are limited by the impurity content found in the diboride source powder. Thus our work focuses on developing a methodology to process the high purity ZrB₂ using spark plasma sintering (SPS) and computational thermodynamics analysis coupled with high-resolution atomic scale electron microscopy. A clear path …