Engineering Commons^™

Hybrid Sintering – The Beneficial Combination Of Sintering Principles, Juergen Hennicke, Tobias Kessel, Sergio Rivera Monte

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

„Hybrid Sintering“ can be defined as a beneficial combination of different sintering principles, e.g. direct and indirect heating, uniaxial and gas pressure, high and low electrical fields (Figure 1). In the technological context this can be completed by debindering, decoupled pre-heating and cooling as well as rate controlled sintering optionally. Hybrid sintering systems enable the development and production of all new material solutions.

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3-Point Measurement In Solid State Devices: (Novel) Artifacts And How To Avoid Them, Tobias Huber, Richard Schlesinger, Markus Kubicek, Jürgen Fleig, Alexander Schmid

Nonstoichiometric Compounds VII

There are two common methods to measure the impedance response of only one electrode of a solid-state electrochemical cell, microelectrodes or a three-terminal configuration. In aqueous electrochemistry, three-terminal configurations are widely used, however, implementing this method in solid-state electrochemistry is highly non-trivial. This work summarizes, which method is most suitable for different applications. We show potential error sources and evaluate each of them quantitatively with special emphasis on their impact in thin film electrode measurements. Evaluation is done by means of finite elements analysis (FEA), electric circuit simulations and conducted measurements.

Three potential error sources were identified as particularly crucial …

Conference Program, Hitoshi Takamura, Roger De Souza, Ryan O’Hayre

Nonstoichiometric Compounds VII

No abstract provided.

Photoluminescence In Sps-Processed Transparent Ce:Yag Ceramics, Avital Wagner, Nachum Frage, Sergey Kalabukhov, Barak Ratzker

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

Ceramic phosphors display great promise for the realization of high-power lighting devices. Cerium-doped yttrium aluminum garnet (Ce:YAG) is commonly used as a phosphor in white light emitting diodes. Therefore, it was chosen as a case study to investigate photoluminescence of transparent ceramic phosphors fabricated by spark plasma sintering (SPS). In the present work, 0.5 at.% Ce:YAG nano-powder was synthesized by a co-precipitation method and subsequently consolidated by SPS into highly transparent ceramic samples. The effect of varying sintering parameters (temperature and pressure) and post-sintering treatments (hot isostatic pressing and air atmosphere thermal treatment) on optical properties was investigated. Correlations between …

Β-Sialon-Based Ceramic Composites By Combustion Synthesis And Spark Plasma Sintering, Evgeny Grigoryev, Vladimir Goltsev, Konstantin Smirnov, Dmitriy Moskovskikh, Aleksey Sedegov

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

Spark-plasma sintering (SPS) of composite ceramics in the β-Si₅AlON₇– system (SiC, TiN, BN) was studied. An effective mechanism of intensification of sintering processes was revealed due to the introduction of h-BN, having a scaly structure and playing the role of a solid lubricant, which improves the compressibility of the sintered powder mixtures under load. For composites containing 0–30 wt. % h-BN, 0–40 wt.% β-SiC, and 0–40 wt. % TiN, with different character distribution of components by volume (homogeneous, layered and gradient), the optimal parameters of the PCA were established, ensuring the achievement of a high level …

Tensile Strength Of Materials Obtained By Electric Pulse Consolidation Of Powders, Evgeny Grigoryev, Vladimir Goltsev, Andrey Osintsev, Aleksandr Plotnikov

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

A wide range of products of modern technology, obtained by electropulse consolidation of powders, has dimensions that do not exceed 10-15 mm in diameter, and their thickness varies from 1 to 10 mm. Standard mechanical testing methods for such sample sizes are often not applicable.

The article investigates the possibility of determining the resistance to fracture of materials obtained from powders by electric pulse consolidation method using the test method for bending thin disks on an annular support and testing short cylinders according to the "Brazilian test". A numerical simulation of the process of bending a thin disk on an …

Microstructure Evolution During High-Pressure Spark Plasma Sintering (Hpsps) Of Transparent Alumina, Barak Ratzker, Sergey Kalabukhov, Nachum Frage, Avital Wagner

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

Applying high-pressure during spark plasma sintering (so-called HPSPS) enables rapid densification of a ceramic powder at relatively lower temperatures, limiting grain growth and allowing fabrication of fine-grained highly transparent ceramics. The present work focuses on the fabrication of fine submicron transparent alumina from untreated commercial powder by HPSPS and the microstructure evolution during consolidation under high applied pressure. The sintering was conducted at relatively low temperatures (1000-1100°C) under high pressure varied from 250 to 800 MPa. We review unique sintering phenomena such as stress-enhanced grain growth and de-sintering, which are related to creep taking place during the final stage of …

Conference Program, Rishi Raj, Olivier Guillon, Hidehiro Yoshida

Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities

No abstract provided.

Statistical Algorithm For Nonuniformity Correction In Focal-Plane Arrays, Majeed M. Hayat, Sergio N. Torres, Ernest Armstrong, Stephen C. Cain, Brian Yasuda

Electrical and Computer Engineering Faculty Research and Publications

A statistical algorithm has been developed to compensate for the fixed-pattern noise associated with spatial nonuniformity and temporal drift in the response of focal-plane array infrared imaging systems. The algorithm uses initial scene data to generate initial estimates of the gain, the offset, and the variance of the additive electronic noise of each detector element. The algorithm then updates these parameters by use of subsequent frames and uses the updated parameters to restore the true image by use of a least-mean-square error finite-impulse-response filter. The algorithm is applied to infrared data, and the restored images compare favorably with those restored …

Managing Healthcare Data Assets As A Complex Adaptive System, Katie Clifton

Systems Science Friday Noon Seminar Series

A major project is underway to develop a shared platform for data and analytics in a highly federated healthcare delivery organization. In the status quo data environment, analysts have integrated information from various domains — medical records, claims, membership — to produce a multitude of reports and analysis. Duplicative, mis-aligned, and siloed datasets were created as an unintended consequence.

One objective of the project is to produce outcomes (reports, analysis) that are more standardized and efficient than the status quo without sacrificing adaptability. Standards and practices are being intentionally developed as a mechanism for this emerging system to achieve more …

Efficacy Of The Localized Aviation Mos Program In Ceiling Flight Category Forecasts, Douglas D. Boyd, Thomas A. Guinn

Publications

(1) Background: Flying in instrument meteorological conditions (IMC) carries an elevated risk of fatal outcome for general aviation (GA) pilots. For the typical GA flight, aerodrome-specific forecasts (Terminal Aerodrome Forecast (TAF), Localized Aviation Model Output Statistics Program (LAMP)) assist the airman in pre-determining whether a flight can be safely undertaken. While LAMP forecasts are more prevalent at GA-frequented aerodromes, the Federal Aviation Administration (FAA) recommends that this tool be used as supplementary to the TAF only. Herein, the predictive accuracy of LAMP for ceiling flight categories of visual flight rules (VFR) and instrument flight rules (IFR) was determined. (2) Methods: …

Characterizing Short-Wave Infrared Fluorescence Of Conventional Near-Infrared Fluorophores, Brook K. Byrd, Margaret R. Folaron, Joseph P. Leonor, Rendall R. Strawbridge, Xu Cao, Petr Bruza, Scott C. Davis

Dartmouth Scholarship

The observed behavior of short-wave infrared (SWIR) light in tissue, characterized by relatively low scatter and subdiffuse photon transport, has generated considerable interest for the potential of SWIR imaging to produce high-resolution, subsurface images of fluorescence activity in vivo. These properties have important implications for fluorescence-guided surgery and preclinical biomedical research. Until recently, translational efforts have been impeded by the conventional understanding that fluorescence molecular imaging in the SWIR regime requires custom molecular probes that do not yet have proven safety profiles in humans. However, recent studies have shown that two readily available near-infrared (NIR-I) fluorophores produce measurable SWIR fluorescence, …

Iron Mediated Organic Preservation In A River Influenced Continental Margin, Neha Ajit Ghaisas

LSU Doctoral Dissertations

Continental margins such as the Mississippi river influenced Louisiana shelf (MIS), are important land-ocean interfaces where excessive water column productivity and rapid burial results in large amounts of organic carbon (OC) being sequestered in the sediments. The preservation of OC in sediments is controlled by a number of processes among which mineral-OC interactions are considered to be more important. Specifically, the interactions between sediment iron (Fe) species and OC have been shown to promote carbon preservation. However, the exact nature of preservation mechanism is not well understood and is based on limited global data, which specifically lacks estimates from large …

Computationally Efficient Strand Eddy Current Loss Calculation In Electric Machines, Alireza Fatemi, Dan M. Ionel, Nabeel Demerdash, Dave A. Staton, Rafal Wrobel, Yew Chuan Chong

Electrical and Computer Engineering Faculty Research and Publications

A fast finite element (FE) based method for the calculation of eddy current losses in the stator windings of randomly wound electric machines is presented in this paper. The method is particularly suitable for implementation in large-scale design optimization algorithms where a qualitative characterization of such losses at higher speeds is most beneficial for identification of the design solutions that exhibit the lowest overall losses including the ac losses in the stator windings. Unlike the common practice of assuming a constant slot fill factor s _f for all the design variations, the maximum s _f in the developed method is …

Freelabel: A Publicly Available Annotation Tool Based On Freehand Traces, Philipe A. Dias, Zhou Shen, Amy Tabb, Henry P. Medeiros

Electrical and Computer Engineering Faculty Research and Publications

Large-scale annotation of image segmentation datasets is often prohibitively expensive, as it usually requires a huge number of worker hours to obtain high-quality results. Abundant and reliable data has been, however, crucial for the advances on image understanding tasks recently achieved by deep learning models. In this paper, we introduce FreeLabel, an intuitive open-source web interface that allows users to obtain high-quality segmentation masks with just a few freehand scribbles, in a matter of seconds. The efficacy of FreeLabel is quantitatively demonstrated by experimental results on the PASCAL dataset as well as on a dataset from the agricultural domain. Designed …

Challenges In Designing A Mentorship Program For Electrical Engineering Freshmen, Branimir Pejcinovic, Melinda Holtzman

Electrical and Computer Engineering Faculty Publications and Presentations

This Work in Progress Innovative Practice Paper addresses three challenges we face when teaching freshmen: a) how to present a wide variety of sub-fields in electrical engineering, b) how to establish the relevance of electrical engineering to things they care about, and c) how to relate electrical engineering to students' experiences. We are attempting to address these through a mentorship program involving recent alumni working with teams of freshman electrical engineering students. Mentors are expected to: (i) come to class and speak about their job experience, (ii) meet with their teams early in the term to help them get started …

Hybrid Field Oriented And Direct Torque Control For Sensorless Bldc Motors Used In Aerial Drones, Kellen Carey, Nathan M. Zimmerman, Cristinel Ababei

Electrical and Computer Engineering Faculty Research and Publications

In this study, a sensorless hybrid control scheme for brushless direct current (BLDC) motors for use in multirotor aerial vehicles is introduced. In such applications, the control scheme must satisfy high-performance demands for a wide range of rotor speeds and must be robust to motor parameter uncertainties and measurement noise. The proposed controller combines field-oriented control (FOC) and direct torque control (DTC) techniques to take benefit of the advantages offered by each of these techniques individually. Simulation results demonstrate the effectiveness of the proposed control scheme over a wide range of rotor speeds as well as good robustness against parameter …

High Friction Surface Treatment Initiatives By Indot: Spec Development, Joseph Bruno

Purdue Road School

In-House Project Design, Special Provision Specification, and Initial Test Results—Highfriction surface treatment (HFST) has been proactively utilized as a cost-effective solution to reducing vehicle crashes at curves across the country. As an initiative, INDOT is currently installing HFST at 26 locations statewide, mainly horizontal curves with high crash rates. This session consists of two presentations to share the information on the development, expected benefits, project design, and initial test results based on the HFST at these locations.

Latex Modified Concrete - Very Early Strength, Bobby Steele

Purdue Road School

INDOT came out with specifications for a very early strength concrete to use on bridge deck overlays. This concrete is fast setting, which allows overlays to be performed over a weekend and benefits the traveling public with a short duration of traffic interference. Cure time to reach the strength requirement is 3 hours. E&B Paving performed the first application with the new spec on August 26, 2018. Many changes were also made to the INDOT Specification Section 722.

Rough Roads Ahead!?, Sarah Reed, Brooke Thomas, Jim Hellmann

Purdue Road School

Have you ever found yourself in the public's cross-hairs when it is time to implement a few roadway improvements? Are you handicapped in your ability to describe the true value of community planning and economic development planning? Come hear from one dynamic trio with the ability to identify issues and opportunities that others might not see and work to uncover even more ways tin which we are better together.

Battery-Free Wireless Strain Measurement Using An Antenna Sensor, Yang Wang

INSPIRE Archived Webinars

A battery-free antenna sensor can wirelessly measure strain on a structure. Bonded to the surface of a base structure, the antenna sensor deforms when the structure is under strain, causing the antenna’s electromagnetic resonance frequency to change. This resonance frequency change can be wirelessly interrogated and recorded by a reader through electromagnetic backscattering. A radio frequency identification (RFID) chip on the sensor harnesses a small amount of energy from the interrogation signal and responds to the reader. The resonance frequency change identified by the reader is then used to determine the strain applied on the structure. The latest antenna sensor …

Use Of Penetrating Asphalt Emulsions To Address High-Void Pavement Areas, Andrew Eicher, Curt Higginbotham

Purdue Road School

Longitudinal joints are high in air voids due to compaction limitations. Lowering the void content of these areas improves the durability of the pavement. Project data indicate that rapid penetrating emulsion (RPE) fills the voids beneath the surface of the pavement, reducing air and water intrusion while maintaining surface texture, whereas traditional emulsions seal the surface only. Lab tests have been developed to quantify the penetrating ability of an emulsion and resistance to water exposure. Join us for a discussion.

Safety Improvements At Horizontal Curves, Joseph Bruno

Purdue Road School

This presentation highlights the progress INDOT has made in improving safety at horizontal curves by upgrading the signing and delineation and by applying high friction surface treatments at some locations. We will also discuss the MUTCD (Manual on Uniform Traffic Control Devices) requirements for signing horizontal curves and the approaching (December 31, 2019) FHWA target date for compliance.

Controlled Anchoring Of Iron Oxide Nanoparticles On Polymeric Nanofibers: Easy Access To Core@Shell Organic-Inorganic Nanocomposites For Magneto-Scaffolds, Hussein Awada, Assala Al Samad, Danielle Laurencin, Ryan Gilbert, Xavier Dumail, Ayman El Jundi, Audrey Bethry, Rebecca Pomrenke, Christopher Johnson, Laurent Lemaire, Florence Franconi, Gautier Félix, Joulia Larionova, Yannick Guari, Benjamin Nottelet

Chemical and Biochemical Engineering Faculty Research & Creative Works

Composites combining superparamagnetic iron oxide nanoparticles (SPIONs) and polymers are largely present in modern (bio)materials. However, although SPIONs embedded in polymer matrices are classically reported, the mechanical and degradation properties of the polymer scaffold are impacted by the SPIONs. Therefore, the controlled anchoring of SPIONs onto polymer surfaces is still a major challenge. Herein, we propose an efficient strategy for the direct and uniform anchoring of SPIONs on the surface of functionalized-polylactide (PLA) nanofibers via a simple free ligand exchange procedure to design PLA@SPIONs core@shell nanocomposites. The resulting PLA@SPIONs hybrid biomaterials are characterized by electron microscopy (scanning electron microscopy and …

Microwave Self-Healing Technology As Airfield Porous Asphalt Friction Course Repair And Maintenance System, Amir Tabakovic, Declan O'Prey, Drew Mckenna, David Woodward

Research and Innovation - Articles

A problem increasingly faced by airport authorities is the maintenance of runways. Due to their large aircraft loadings associated with take-off and landing operations, runways experience surface deterioration. Poor quality runway surfaces cannot be tolerated in such an environment. Maintenance issues must be carried out to maximise safety and minimise the risk of aircraft damage. A recent development has been the introduction of self-healing technologies such as rejuvenator encapsulation, induction and microwave heating to address these issues. This paper summarises a laboratory investigation to determine the effectiveness of microwave self-healing for crack repair of Porous Friction Course (PFC) used for …

Incidence Of An Astronaut Not Sealing The Pressure Garment Visor On Reentry, Cameron M. Smith, Trent Tresch

Journal of Human Performance in Extreme Environments

Audiovisual records of a Project Mercury pilot’s activities during an orbital flight indicate that his visor was left open during reentry and descent to the sea surface, phases of flight during which cabin pressure loss was to be mitigated by suit pressurization; however, the suit could not have been pressurized with the visor open. Thus, for a presently unknown reason, a critical safety step—sealing the visor and making a pressure suit integrity test before reentry—was overlooked in this flight. Later, Space Shuttle flights were carried out with visors unsealed for much of the launch and landing phases, with the false …

Leveraging Telematics And Weather Data To Study The Productivity Of Roadside Mowers, Jijo K. Mathew, Matt Kraushar

Purdue Road School

Mowing activities are usually reported by daily work orders and it is difficult to obtain quantitative information characterizing the utilization and productivity of the mowing operations. This research uses telematics data from commercial sensors to track the daily activity of seven mowers in the Fort Wayne district. Weather data from NOAA was also captured to estimate the weather related delays. During a one-month period, the mowers collectively covered a total of around 1170 miles and an area of nearly 1800 acres of mowing. Crews worked alternative work schedules with extended hours four days a week. On an average 9.5 hour …

Assessing Slope Instabilities, Victoria Leffel, Joey Franzino

Purdue Road School

INDOT’s Geotechnical Services Section has recently implemented a slide ArcGIS Collector app to provide a systematic approach to collecting and managing unsafe or failed slopes/embankments needed for decision making. A brief background in Indiana landslide geology will be given, then we will review the process of how to inventory slopes through the Collector app and identify potentially hazardous slopes. The session will end with a discussion of current engineering practices INDOT is using to correct landslides.

Bayesian Compressive Sensing Of Sparse Signals With Unknown Clustering Patterns, Mohammad Shekaramiz, Todd K. Moon, Jacob H. Gunther

Electrical and Computer Engineering Faculty Publications

We consider the sparse recovery problem of signals with an unknown clustering pattern in the context of multiple measurement vectors (MMVs) using the compressive sensing (CS) technique. For many MMVs in practice, the solution matrix exhibits some sort of clustered sparsity pattern, or clumpy behavior, along each column, as well as joint sparsity across the columns. In this paper, we propose a new sparse Bayesian learning (SBL) method that incorporates a total variation-like prior as a measure of the overall clustering pattern in the solution. We further incorporate a parameter in this prior to account for the emphasis on the …

Improving Wastewater Treatment Using Algal Biofilms And Bioenergy, Nathan Guymon

Research on Capitol Hill

This project represents a collaboration between Utah State University, Central Valley Water Reclamation Facility (CVWRF), and WesTech Engineering, Inc. The goal of the project is to help water treatment plants meet state nutrient standards and reduce operating costs. This is being accomplished in three major sections:

1. Wastewater treatment – microalgae is grown to remove nitrogen and phosphorus from water.

2. Biogas generation – the microalgae is harvested and processed to produce methane gas used to generate power.

3. Fertilizer production – nutrients are also collected from the wastewater and turned into high-value fertilizer.

By creating systems that remove nutrients …