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Articles 69541 - 69570 of 196757

Full-Text Articles in Engineering

Evaluating The Impacts Of Acp Management On The Energy Performance Of Hydrothermal Liquefaction Via Nutrient Recovery, Sarah Bauer, Fangwei Cheng, Lisa Colosi Feb 2019

Evaluating The Impacts Of Acp Management On The Energy Performance Of Hydrothermal Liquefaction Via Nutrient Recovery, Sarah Bauer, Fangwei Cheng, Lisa Colosi

Henry M. Rowan College of Engineering Departmental Research

Hydrothermal liquefaction (HTL) is of interest in producing liquid fuels from organic waste, but the process also creates appreciable quantities of aqueous co-product (ACP) containing high concentrations of regulated wastewater pollutants (e.g., organic carbon, nitrogen (N), and phosphorus (P)). Previous literature has not emphasized characterization, management, or possible valorization of ACP wastewaters. This study aims to evaluate one possible approach to ACP management via recovery of valuable scarce materials. Equilibrium modeling was performed to estimate theoretical yields of struvite (MgNH4PO4·6H2O) from ACP samples arising from HTL processing of selected waste feedstocks. Experimental analyses were conducted to evaluate the accuracy of …


Professor Randy Martin First To Speak At Usu Research Landscapes Event | College Of Engineering, Utah State University Feb 2019

Professor Randy Martin First To Speak At Usu Research Landscapes Event | College Of Engineering, Utah State University

College of Engineering News

Cllege of Engineering professor and air quality expert Randy Martin will be the first to present at Utah State University’s upcoming Research Landscapes speaker series on Tuesday, Feb. 26. The series highlights findings from statewide research on air, water and land.


Effect Of Pt Promotion On The Ni-Catalyzed Deoxygenation Of Tristearin To Fuel-Like Hydrocarbons, Ryan Loe, Kelsey Huff, Morgan Walli, Tonya Morgan, Dali Qian, Robert Pace, Yang Song, Mark Isaacs, Eduardo Santillan-Jimenez, Mark Crocker Feb 2019

Effect Of Pt Promotion On The Ni-Catalyzed Deoxygenation Of Tristearin To Fuel-Like Hydrocarbons, Ryan Loe, Kelsey Huff, Morgan Walli, Tonya Morgan, Dali Qian, Robert Pace, Yang Song, Mark Isaacs, Eduardo Santillan-Jimenez, Mark Crocker

Center for Applied Energy Research Faculty and Staff Publications

Pt represents an effective promoter of supported Ni catalysts in the transformation of tristearin to green diesel via decarbonylation/decarboxylation (deCOx), conversion increasing from 2% over 20% Ni/Al2O3 to 100% over 20% Ni-0.5% Pt/Al2O3 at 260 °C. Catalyst characterization reveals that the superior activity of Ni-Pt relative to Ni-only catalysts is not a result of Ni particle size effects or surface area differences, but rather stems from several other phenomena, including the improved reducibility of NiO when Pt is present. Indeed, the addition of a small amount of Pt to the supported Ni …


Iot And Digitization Will Reconnect System Engineering And Science, John Blyler Feb 2019

Iot And Digitization Will Reconnect System Engineering And Science, John Blyler

Systems Science Friday Noon Seminar Series

The fully connected world is quickly becoming a reality. Architects and developers of this new world must understand both the hardware and software basics of IoT and IIoT systems as well as the proven way to deal with the complexities of the integration of sensors, processors, wireless connectivity, edge to cloud networks, data partitioning and processing, AI, machine language, digital threads and twins, and much more. Such complexity can only be handled with a systems-of-systems (SoS) engineering approach.

But while systems engineering may hold many of the solutions to IoT challenges, systems engineering must evolve from its traditional role. Some …


Long-Term, Super-Resolution Imaging Of Amyloid Structures Using Transient Amyloid Binding Microscopy, Tianben Ding, Kevin Spehar, Jan Bieschke, Matthew D. Lew Feb 2019

Long-Term, Super-Resolution Imaging Of Amyloid Structures Using Transient Amyloid Binding Microscopy, Tianben Ding, Kevin Spehar, Jan Bieschke, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

Amyloid fibrils and tangles are signatures of Alzheimer disease, but nanometer-sized aggregation intermediates are hypothesized to be the structures most toxic to neurons. The structures of these oligomers are too small to be resolved by conventional light microscopy. We have developed a simple and versatile method, called transient amyloid binding (TAB), to image amyloid structures with nanoscale resolution using amyloidophilic dyes, such as Thioflavin T, without the need for covalent labeling or immunostaining of the amyloid protein. Transient binding of ThT molecules to amyloid structures over time generates photon bursts that are used to localize single fluorophores with nanometer precision. …


Road To Hayabusa2 From Cansat And Cubesat, Yuichi Tsuda Feb 2019

Road To Hayabusa2 From Cansat And Cubesat, Yuichi Tsuda

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Yuichi Tsuda titled "Road to Hayabusa2 from CanSat and CubeSat" from February 22, 2019.


Evaluation Of Novel Hemocompatible Surface Coatings For Extracorporeal Life Support: A Biocompatible Alternative To Systemic Anticoagulation, Teryn Rose Roberts Feb 2019

Evaluation Of Novel Hemocompatible Surface Coatings For Extracorporeal Life Support: A Biocompatible Alternative To Systemic Anticoagulation, Teryn Rose Roberts

USF Tampa Graduate Theses and Dissertations

Extracorporeal life support (ECLS) is a class of technologies used to support or replace the function of failing organs. During ECLS, blood is withdrawn from systemic circulation and circulated through an artificial organ or “treatment membrane” that performs the function of the failing organ, prior to return to systemic circulation. While ECLS provides life-saving therapy to wide patient populations from pre-term infants to combat-wounded soldiers, this therapy is limited due to secondary thrombotic and bleeding complications that result from: 1) exposure of blood to the foreign surfaces in the device circuit and 2) administration of anticoagulant drugs to prevent clot …


Fundamental Limits Of Measuring Single-Molecule Rotational Mobility, Oumeng Zhang, Matthew D. Lew Feb 2019

Fundamental Limits Of Measuring Single-Molecule Rotational Mobility, Oumeng Zhang, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

Various methods exist for measuring molecular orientation, thereby providing insight into biochemical activities at nanoscale. Since fluorescence intensity and not electric field is detected, these methods are limited to measuring even-order moments of molecular orientation. However, any measurement noise, for example photon shot noise, will result in nonzero measurements of any of these even-order moments, thereby causing rotationally-free molecules to appear to be partially constrained. Here, we build a model to quantify measurement errors in rotational mobility. Our theoretical framework enables scientists to choose the optimal single-molecule orientation measurement technique for any desired measurement accuracy and photon budget.


Barn Considerations For Cash Hay Operations, Morgan D. Hayes Feb 2019

Barn Considerations For Cash Hay Operations, Morgan D. Hayes

Kentucky Alfalfa and Stored Forage Conference

A well designed and built a barn can be invaluable for cash hay operation. Barn provide opportunity to reduce losses in dry matter and help maintain quality throughout the winter. There are numerous styles of barns that hay producers can purchase or build themselves. Wood frame structures, often with metal roofs and metal sides, are fairly common. You can also build barns with a steel structure with or without metal siding on the walls. Hoop barns are another common hay storage structure - particularly common with round bale storage. All, however, provide valuable storage for hay. There are four areas …


Surface And Interface Properties In Thin-Film Solar Cells: Using Soft X-Rays And Electrons To Unravel The Electronic And Chemical Structure, Lothar Weinhardt, Dirk Hauschild, Clemens Heske Feb 2019

Surface And Interface Properties In Thin-Film Solar Cells: Using Soft X-Rays And Electrons To Unravel The Electronic And Chemical Structure, Lothar Weinhardt, Dirk Hauschild, Clemens Heske

Chemistry and Biochemistry Faculty Research

Thin‐film solar cells have great potential to overtake the currently dominant silicon‐based solar cell technologies in a strongly growing market. Such thin‐film devices consist of a multilayer structure, for which charge‐carrier transport across interfaces plays a crucial role in minimizing the associated recombination losses and achieving high solar conversion efficiencies. Further development can strongly profit from a high‐level characterization that gives a local, electronic, and chemical picture of the interface properties, which allows for an insight‐driven optimization. Herein, the authors' recent progress of applying a “toolbox” of high‐level laboratory‐ and synchrotron‐based electron and soft X‐ray spectroscopies to characterize the chemical …


Flow-Induced Stresses And Displacements In Jointed Concrete Pipes Installed By Pipe Jacking Method, Moses Karakouzian, Mehrdad Karami, Mohammad Nazari-Sharabian, Sajjad Ahmad Feb 2019

Flow-Induced Stresses And Displacements In Jointed Concrete Pipes Installed By Pipe Jacking Method, Moses Karakouzian, Mehrdad Karami, Mohammad Nazari-Sharabian, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

Transient flows result in unbalanced forces and high pressure in pipelines. Under these conditions, the combined effects of flow-induced forces along with sudden pipe displacements can create cracks in the pipeline, especially at the junctions. This situation consequently results in water leakage and reduced operational efficiency of the pipeline. In this study, displacements and stresses in a buried pressurized water transmission pipe installed by pipe jacking method are investigated using numerical modeling and considering interactions between fluid, pipe, and soil. The analyses were performed consecutively under no-flow, steady flow, and transient flow conditions, in order to investigate the effects of …


Polydopamine And Collagen Coated Micro-Grated Polydimethylsiloxane For Human Mesenchymal Stem Cell Culture, Dhavan Sharma, Wenkai Jia, Fei Long, Shweta Pati, Qing-Hui Chen, Yibing Qyang, Bruce P. Lee, Chang Kyoung Choi, Feng Zhao Feb 2019

Polydopamine And Collagen Coated Micro-Grated Polydimethylsiloxane For Human Mesenchymal Stem Cell Culture, Dhavan Sharma, Wenkai Jia, Fei Long, Shweta Pati, Qing-Hui Chen, Yibing Qyang, Bruce P. Lee, Chang Kyoung Choi, Feng Zhao

Department of Biomedical Engineering Publications

Natural tissues contain highly organized cellular architecture. One of the major challenges in tissue engineering is to develop engineered tissue constructs that promote cellular growth in physiological directionality. To address this issue, micro-patterned polydimethylsiloxane (PDMS) substrates have been widely used in cell sheet engineering due to their low microfabrication cost, higher stability, excellent biocompatibility, and most importantly, ability to guide cellular growth and patterning. However, the current methods for PDMS surface modification either require a complicated procedure or generate a non-uniform surface coating, leading to the production of poor-quality cell layers. A simple and efficient surface coating method is critically …


Linear Stability Analysis Of Subaqueous Bedforms Using Direct Numerical Simulations, ‪Nadim Zgheib, S. Balachandar Feb 2019

Linear Stability Analysis Of Subaqueous Bedforms Using Direct Numerical Simulations, ‪Nadim Zgheib, S. Balachandar

Mechanical Engineering Faculty Publications

We present results on the formation of ripples from linear stability analysis. The analysis is coupled with direct numerical simulations of turbulent open-channel flow over a fixed sinusoidal bed. The presence of the sediment bed is accounted for using the immersed boundary method. The simulations are used to extract the bed shear stress and consequently the sediment transport rate. The approach is different from traditional linear stability analysis in the sense that the phase lag between the bed topology and the sediment flux is obtained from the three-dimensional turbulent simulations. The stability analysis is performed on the Exner equation, whose …


Project Selection: The $1 Trillion Decisions, Leonard Nethercutt Feb 2019

Project Selection: The $1 Trillion Decisions, Leonard Nethercutt

Operations Management Presentations

This webinar will discuss project selection with a focus on both strategic and fi­nancial factors. Project selection directly influences the future results of a busi­ness either positively or negatively over time. During this presentation, we will examine the important link between strategic management, project management, and operations management to create future results and value. You will learn project selection methods and tips to help your organization make a positive impact on the future of your business.


Quantifying And Correcting For Clay Content Effects On Soil Water Measurement By Reflectometers, Jasreman Singh, Tsz Him Lo, Daran Rudnick, Suat Irmak, Humberto Blanco-Canqui Feb 2019

Quantifying And Correcting For Clay Content Effects On Soil Water Measurement By Reflectometers, Jasreman Singh, Tsz Him Lo, Daran Rudnick, Suat Irmak, Humberto Blanco-Canqui

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The presence of clay particles increases the specific surface area of a soil and can affect the calibration of electromagnetic soil water sensors including reflectometers. To quantify and correct for this effect in two relatively new reflectometers, three TDR315 and three CS655 sensors were installed in each of five soils with clay content ranging from 5 to 49%. As the soils were dried in a temperature controlled room, sensor reported soil volumetric water content (θv) according to the factory calibration was compared against reference θv determined by weighing the soils. Sensor reported θv was similar to …


Near-Surface Material Phases And Microstructure Of Scandate Cathodes, Xiaotao Liu, Bernard K. Vancil, Matthew J. Beck, Thomas John Balk Feb 2019

Near-Surface Material Phases And Microstructure Of Scandate Cathodes, Xiaotao Liu, Bernard K. Vancil, Matthew J. Beck, Thomas John Balk

Chemical and Materials Engineering Faculty Publications

Scandate cathodes that were fabricated using the liquid-solid process and that exhibited excellent emission performance were characterized using complementary state-of-the-art electron microscopy techniques. Sub-micron BaAl2O4 particles were observed on the surfaces and edges of tungsten particles, as seen in cross-section samples extracted from the scandate cathode surface regions. Although several BaAl2O4 particles were observed to surround smaller Sc2O3 nanoparticles, no chemical mixing of the two oxides was detected, and in fact the distinct oxide phases were separately verified by chemical analysis and also by 3D elemental tomography. Nanobeam electron diffraction confirmed …


Usu Aggieair Program Selected For Critical National Airspace Operation | College Of Engineering, Utah State University Feb 2019

Usu Aggieair Program Selected For Critical National Airspace Operation | College Of Engineering, Utah State University

College of Engineering News

Utah State University’s premier unmanned aerial systems organization will take part in a highly anticipated NASA-led operation.


Compensating Misalignment Using Dynamic Random-Effect Control System: A Case Of High-Mixed Wafer Fabrication, Marzieh Khakifirooz, Chen-Fu Chien, Mahdi Fathi Feb 2019

Compensating Misalignment Using Dynamic Random-Effect Control System: A Case Of High-Mixed Wafer Fabrication, Marzieh Khakifirooz, Chen-Fu Chien, Mahdi Fathi

BCoE Publications

It is vital to have an exclusive modification in semiconductor production process because of meeting differentiated customer demands in dynamic and competitive global minuscule semiconductor technology market and the highly complex fabrication process. In this paper, we propose a control system based on the dynamic mixed-effect least-square support vector regression (LS-SVR) control system for overlay error compensation with stochastic metrology delay to minimize the misalignment of the patterning process. Moreover, for the stability of the control system in the presence of metrology delay and to deal with nonlinearity among the overlay factors, the novel Lyapunov-based kernel function is merged with …


Characterization And Quantification Of Highly Sulfated Glycosaminoglycan Isomers By Gated-Trapped Ion Mobility Spectrometry Negative Electron Transfer Dissociation Ms/Ms, Juan Wei, Jiandong Wu, Yang Tang, Mark E. Ridgeway, Melvin A. Park, Catherine E. Costello, Joseph Zaia, Cheng Lin Feb 2019

Characterization And Quantification Of Highly Sulfated Glycosaminoglycan Isomers By Gated-Trapped Ion Mobility Spectrometry Negative Electron Transfer Dissociation Ms/Ms, Juan Wei, Jiandong Wu, Yang Tang, Mark E. Ridgeway, Melvin A. Park, Catherine E. Costello, Joseph Zaia, Cheng Lin

Chemical and Biochemical Engineering Faculty Research & Creative Works

Glycosaminoglycans (GAGs) Play Vital Roles in Many Biological Processes and Are Naturally Present as Complex Mixtures of Polysaccharides with Tremendous Structural Heterogeneity, Including Many Structural Isomers. Mass Spectrometric Analysis of GAG Isomers, in Particular Highly Sulfated Heparin (Hep) and Heparan Sulfate (HS), is Challenging Because of their Structural Similarity and Facile Sulfo Losses during Analysis. Herein, We Show that Highly Sulfated Hep/HS Isomers May Be Resolved by Gated-Trapped Ion Mobility Spectrometry (Gated-TIMS) with Negligible Sulfo Losses. Subsequent Negative Electron Transfer Dissociation (NETD) Tandem Mass Spectrometry (MS/MS) Analysis of TIMS-Separated Hep/HS Isomers Generated Extensive Glycosidic and Cross-Ring Fragments for Confident Isomer …


Substrate Support Ring For More Uniform Layer Thickness, Heng Pan, Lara Hawrylchak, Christopher S. Olsen Feb 2019

Substrate Support Ring For More Uniform Layer Thickness, Heng Pan, Lara Hawrylchak, Christopher S. Olsen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Embodiments of substrate support rings providing more uniform thickness of layers deposited or grown on a substrate are provided herein. In some embodiments, a substrate support ring includes: an inner ring with a centrally located support surface to support a substrate; and an outer ring extending radially outward from the support surface, wherein the outer ring comprises a reaction surface area disposed above and generally parallel to a support plane of the support surface, and wherein the reaction surface extends beyond the support surface by about 24 mm to about 45 mm.


The Bridge Between Beauty And Functionality, Justin R. Vander Werff Feb 2019

The Bridge Between Beauty And Functionality, Justin R. Vander Werff

Faculty Work Comprehensive List

"While our human creatureliness and limited understanding often lead us to pit form and function against each other, God provides glimpses of their unity."

Posting about ­­­­­­­­balancing aesthetics and practicality in design from In All Things - an online journal for critical reflection on faith, culture, art, and every ordinary-yet-graced square inch of God’s creation.

https://inallthings.org/the-bridge-between-beauty-and-functionality/


Forcespinning Technique For The Production Of Poly(D,L-Lactic Acid) Submicrometer Fibers: Process–Morphology–Properties Relationship, Victoria Padilla-Gainza, Graciela Morales, Heriberto Rodríguez-Tobías, Karen Lozano Feb 2019

Forcespinning Technique For The Production Of Poly(D,L-Lactic Acid) Submicrometer Fibers: Process–Morphology–Properties Relationship, Victoria Padilla-Gainza, Graciela Morales, Heriberto Rodríguez-Tobías, Karen Lozano

Mechanical Engineering Faculty Publications

This work addresses a systematic study for the process development and optimization of poly(d,l-lactic acid) (PDLLA) submicrometer fibers utilizing the centrifugal spinning technique known as Forcespinning. This study analyzes the effect of polymer concentration (8, 10, and 12 wt %) and angular speed on the fiber morphology, diameter distribution, and fiber yield. The increase in polymer concentration and angular speed favored the formation of continuous and homogeneous submicrometer fibers with an absence of bead formation and higher output. The optimal conditions were established considering the morphological characteristics that exhibit a greater surface area (homogeneous and submicrometer fibers); and they were …


Myopic Versus Farsighted Behaviors In A Low-Carbon Supply Chain With Reference Emission Effects, Jun Wang, Xianxue Cheng, Xinyu Wang, Hongtao Yang, Shuhua Zhang Feb 2019

Myopic Versus Farsighted Behaviors In A Low-Carbon Supply Chain With Reference Emission Effects, Jun Wang, Xianxue Cheng, Xinyu Wang, Hongtao Yang, Shuhua Zhang

Mathematical Sciences Faculty Research

The increased carbon emissions cause relatively climate deterioration and attract more attention of governments, consumers, and enterprises to the low-carbon manufacturing. This paper considers a dynamic supply chain, which is composed of a manufacturer and a retailer, in the presence of the cap-and-trade regulation and the consumers’ reference emission effects. To investigate the manufacturer’s behavior choice and its impacts on the emission reduction and pricing strategies together with the profits of both the channel members, we develop a Stackelberg differential game model in which the manufacturer acts in both myopic and farsighted manners. By comparing the equilibrium strategies, it can …


Applications Of Supervised Machine Learning In Autism Spectrum Disorder Research: A Review, Kayleigh K. Hyde, Marlena N. Novack, Nicholas Lahaye, Chelsea Parlett-Pelleriti, Raymond Anden, Dennis R. Dixon, Erik Linstead Feb 2019

Applications Of Supervised Machine Learning In Autism Spectrum Disorder Research: A Review, Kayleigh K. Hyde, Marlena N. Novack, Nicholas Lahaye, Chelsea Parlett-Pelleriti, Raymond Anden, Dennis R. Dixon, Erik Linstead

Engineering Faculty Articles and Research

Autism spectrum disorder (ASD) research has yet to leverage "big data" on the same scale as other fields; however, advancements in easy, affordable data collection and analysis may soon make this a reality. Indeed, there has been a notable increase in research literature evaluating the effectiveness of machine learning for diagnosing ASD, exploring its genetic underpinnings, and designing effective interventions. This paper provides a comprehensive review of 45 papers utilizing supervised machine learning in ASD, including algorithms for classification and text analysis. The goal of the paper is to identify and describe supervised machine learning trends in ASD literature as …


Harnessing Neurovascular Interaction To Guide Axon Growth., Paul P Partyka, Ying Jin, Julien Bouyer, Angelica Dasilva, George A Godsey, Robert G Nagele, Itzhak Fischer, Peter Galie Feb 2019

Harnessing Neurovascular Interaction To Guide Axon Growth., Paul P Partyka, Ying Jin, Julien Bouyer, Angelica Dasilva, George A Godsey, Robert G Nagele, Itzhak Fischer, Peter Galie

Henry M. Rowan College of Engineering Departmental Research

Regulating the intrinsic interactions between blood vessels and nerve cells has the potential to enhance repair and regeneration of the central nervous system. Here, we evaluate the efficacy of aligned microvessels to induce and control directional axon growth from neural progenitor cells in vitro and host axons in a rat spinal cord injury model. Interstitial fluid flow aligned microvessels generated from co-cultures of cerebral-derived endothelial cells and pericytes in a three-dimensional scaffold. The endothelial barrier function was evaluated by immunostaining for tight junction proteins and quantifying the permeability coefficient t (~10−7 cm/s). Addition of neural progenitor cells to the co-culture …


The Influence Of Asphalt Ageing On Induction Healing Effect On Porous Asphalt Concrete, Shi Xu, Xueyan Liu, Amir Tabakovic, Erik Schlangen Feb 2019

The Influence Of Asphalt Ageing On Induction Healing Effect On Porous Asphalt Concrete, Shi Xu, Xueyan Liu, Amir Tabakovic, Erik Schlangen

Articles

Induction healing is a proven technology which is able to improve the self‐healing capacity of asphalt concrete. Healing is achieved via electromagnetic current produced by passing induction machine, where steel asphalt constituents heat up which in turn soften the bitumen in the asphalt layer, allowing it to flow and close cracks, repairing the damage. This paper reports on the study which investigated the influence of ageing on the healing capacity of Porous Asphalt (PA) concrete. Porous Asphalt concrete mix was prepared first, then subjected to an accelerated (laboratory) ageing process using a ventilated oven. In order to further evaluate the …


American Sign Language Recognition Using Machine Learning And Computer Vision, Kshitij Bantupalli, Ying Xie Feb 2019

American Sign Language Recognition Using Machine Learning And Computer Vision, Kshitij Bantupalli, Ying Xie

Master of Science in Computer Science Theses

Speech impairment is a disability which affects an individual’s ability to communicate using speech and hearing. People who are affected by this use other media of communication such as sign language. Although sign language is ubiquitous in recent times, there remains a challenge for non-sign language speakers to communicate with sign language speakers or signers. With recent advances in deep learning and computer vision there has been promising progress in the fields of motion and gesture recognition using deep learning and computer vision-based techniques. The focus of this work is to create a vision-based application which offers sign language translation …


Modeling Of Grace-Derived Groundwater Information In The Colorado River Basin, Md Mafuzur Rahaman, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad Feb 2019

Modeling Of Grace-Derived Groundwater Information In The Colorado River Basin, Md Mafuzur Rahaman, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

Groundwater depletion has been one of the major challenges in recent years. Analysis of groundwater levels can be beneficial for groundwater management. The National Aeronautics and Space Administration’s twin satellite, Gravity Recovery and Climate Experiment (GRACE), serves in monitoring terrestrial water storage. Increasing freshwater demand amidst recent drought (2000–2014) posed a significant groundwater level decline within the Colorado River Basin (CRB). In the current study, a non-parametric technique was utilized to analyze historical groundwater variability. Additionally, a stochastic Autoregressive Integrated Moving Average (ARIMA) model was developed and tested to forecast the GRACE-derived groundwater anomalies within the CRB. The ARIMA model …


Dynamic Response Of A Tunable Mems Accelerometer Based On Repulsive Force, Meysam Daeichin, Mehmet Ozdogan, Shahrzad Towfighian, Ronald Miles Feb 2019

Dynamic Response Of A Tunable Mems Accelerometer Based On Repulsive Force, Meysam Daeichin, Mehmet Ozdogan, Shahrzad Towfighian, Ronald Miles

Mechanical Engineering Faculty Scholarship

This paper describes a tunable MEMS electrostatic accelerometer that uses repulsive electrode configuration so that the design is not hampered by capacitive pull-in instability. The repulsive force configuration enables the increase of DC bias voltage without suffering from the pull-in failure mode. This flexibility in increasing voltage can be employed as a tuning parameter to widen the working frequency range and to improve the robustness of the accelerometer. A lumped parameter model is developed to simulate the response of the microstructure under a combination of electrostatic and dynamic mechanical loading. The electrostatic force is estimated using a finite element simulation. …


Muscle Atrophy Marker Expression Differs Between Rotary Cell Culture System And Animal Studies, Charles P. Harding, Elizabeth Vargis Feb 2019

Muscle Atrophy Marker Expression Differs Between Rotary Cell Culture System And Animal Studies, Charles P. Harding, Elizabeth Vargis

Biological Engineering Faculty Publications

Muscular atrophy, defined as the loss of muscle tissue, is a serious issue for immobilized patients on Earth and for humans during spaceflight, where microgravity prevents normal muscle loading. In vitro modeling is an important step in understanding atrophy mechanisms and testing countermeasures before animal trials. The most ideal environment for modeling must be empirically determined to best mimic known responses in vivo. To simulate microgravity conditions, murine C2C12 myoblasts were cultured in a rotary cell culture system (RCCS). Alginate encapsulation was compared against polystyrene microcarrier beads as a substrate for culturing these adherent muscle cells. Changes after culture …