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Reducing Costs While Maintaining Learning Outcomes Using Blended, Flipped, And Mastery Pedagogy To Teach Introduction To Environmental Engineering, Daniel B. Oerther Jun 2017

Reducing Costs While Maintaining Learning Outcomes Using Blended, Flipped, And Mastery Pedagogy To Teach Introduction To Environmental Engineering, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

As part of a cost-savings initiative, an existing course of 'introduction to environmental engineering' offered using a 'traditional' format of didactic class meetings supplemented with hands-on laboratory sessions, was changed significantly. The 'modified' format uses 'blended', 'flipped', and 'mastery' approaches to teach "2601: Fundamentals of Environmental Engineering" to approximately 60 sophomores pursuing baccalaureate degrees in environmental, civil, or architectural engineering, each semester. This paper presents a summary of the results from eight course offerings over a period of four years to more than 450 total students. Assessments included student grades; open-ended invitations for anonymous feedback at the end of each …


Using Nursing Theory To Improve The Teaching Of Engineering Practice, Daniel B. Oerther Jun 2017

Using Nursing Theory To Improve The Teaching Of Engineering Practice, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Engineering education includes both classroom training in sciences and professional skills as well as learning-through-doing to integrate practice and engineering design into the future licensed Professional Engineer (PE). In a similar manner, nursing education includes both classroom training in sciences and professional skills as well as learning through doing to integrate practice and caring into the future licensed Registered Nurse (RN). From the mid-19th century until modern day, the fields of environmental engineering and community health nursing have worked side-by-side to prevent disease while promoting health and wellness. This paper provides a synthesis of previously published case studies by the …


Using The Voice Of The Student To Evaluate Learning Management Systems, Elizabeth A. Cudney, Susan L. Murray, Brittany Groner, Katie M. Kaczmarek, Bonnie Wilt, Kamaria Blaney, Julie Phelps Jun 2017

Using The Voice Of The Student To Evaluate Learning Management Systems, Elizabeth A. Cudney, Susan L. Murray, Brittany Groner, Katie M. Kaczmarek, Bonnie Wilt, Kamaria Blaney, Julie Phelps

Engineering Management and Systems Engineering Faculty Research & Creative Works

A learning management system is an educational tool employed in higher education to organize, document, track, report, and deliver courses. Selecting the appropriate learning management system is a critical decision for a university. This study explores the usability of two leading systems, Blackboard and Canvas, from the students’ perspective. The goal is to gather and analyze user preferences in order to select an appropriate learning management system. Data was collected through surveys of student’s experience with the two learning management systems. The survey evaluated the ease of the following tasks: finding course documents, viewing grades, ease of navigation, intuitiveness, and …


Heteromer Nanostars By Spontaneous Self-Assembly, Caitlin Brocker, Hannah Kim, Daniel Smith, Sutapa Barua Jun 2017

Heteromer Nanostars By Spontaneous Self-Assembly, Caitlin Brocker, Hannah Kim, Daniel Smith, Sutapa Barua

Chemical and Biochemical Engineering Faculty Research & Creative Works

Heteromer star-shaped nanoparticles have the potential to carry out therapeutic agents, improve intracellular uptake, and safely release drugs after prolonged periods of residence at the diseased site. A one-step seed mediation process was employed using polylactide-co-glycolic acid (PLGA), polyvinyl alcohol (PVA), silver nitrate, and tetrakis(hydroxymethyl)phosphonium chloride (THPC). Mixing these reagents followed by UV irradiation successfully produced heteromer nanostars containing a number of arm chains attached to a single core with a high yield. The release of THPC from heteromer nanostars was tested for its potential use for breast cancer treatment. The nanostars present a unique geometrical design exhibiting a significant …


Corrosion Map For Metal Pipes In Coastal Louisiana, Sanjay Tewari Jun 2017

Corrosion Map For Metal Pipes In Coastal Louisiana, Sanjay Tewari

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Transportation agencies often allow metal pipes as an option for cross drains under/along roads and highways. Metal culverts can corrode over time at various rates based on their environmental conditions (e.g., corrosive nature of coastal soils, high water table, and saltwater intrusion).

This project was focused on applying available soil data, such as spatial distribution of soil types and soil characteristics (e.g., pH and conductivity), towards creating a Geographic Information System (GIS) based map to identify corrosion zones in coastal Louisiana. The effect of the soil characteristics (pH and conductivity) was incorporated in to the published corrosion models for calculating …


The Sound Source As An Indicator Of Sound Verbs' Semantic Behavior During The Synthesis Process, Irina V. Ivliyeva Jun 2017

The Sound Source As An Indicator Of Sound Verbs' Semantic Behavior During The Synthesis Process, Irina V. Ivliyeva

Arts, Languages and Philosophy Faculty Research & Creative Works

The article examines the predictability of Russian verbal modifications during the process of word formation synthesis. The main reasons for modifiers' combinatorial irregularity with respect to semantically connected sound verbs are identified. For the first time ever, the sound source, as the primary factor in determining the word formation synthesis' results, is described from three perspectives: semantic, lexicographic, and denotative. Using various parameters relevant for both sound source and semantic modifiers, the sound verbs are subjected to combinatorial testing. The nature of dynamic dependency between the results of word formation synthesis, the distinguishing characteristics of modifiers, and the semantic range …


Antenna Design For Small Uav Locator Applications, Randall L. Musselman, Steve Eugene Watkins Jun 2017

Antenna Design For Small Uav Locator Applications, Randall L. Musselman, Steve Eugene Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

An antenna design problem is presented for a small UAV application. A UAV locator system must include an on-board transmitter with the capability to provide a beacon signal, in the event of a crash, and a receiver that is tailored for a transmitter hunt. This specific context for applying antenna theory allows a variety of design constraints, technical approaches, performance measures, and required results. The paper provides a structure for organizing the material, example approaches that illustrate possible design choices, and recommendations on educational implementation.


Raman Spectral Variation For Human Fingernails Of Postmenopausal Women Is Dependent On Fracture Risk And Osteoporosis Status, J. R. Beattie, M. C. Caraher, N. M. Cummins, O. M. O'Driscoll, R. Eastell, S. H. Ralston, Mark R. Towler Jun 2017

Raman Spectral Variation For Human Fingernails Of Postmenopausal Women Is Dependent On Fracture Risk And Osteoporosis Status, J. R. Beattie, M. C. Caraher, N. M. Cummins, O. M. O'Driscoll, R. Eastell, S. H. Ralston, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Patients diagnosed with osteoporosis have reported loss of fingernail resilience as the disease progresses. Keratin is the predominant protein in human nail tissue, and its structure has been postulated to be different in fingernails clipped from subjects who have sustained fragility fractures and those who have not, which may offer a window into the donor's bone health. This study was designed to qualify these differences, which may lead to the development of a novel screening tool for fracture risk. Raman spectroscopy was used to measure the fingernails of 633 postmenopausal women who presented at six fracture clinics located across the …


Receiver Function And Gravity Constraints On Crustal Structure And Vertical Movements Of The Upper Mississippi Embayment And Ozark Uplift, Lin Liu, Stephen S. Gao, Kelly H. Liu, Kevin Lee Mickus Jun 2017

Receiver Function And Gravity Constraints On Crustal Structure And Vertical Movements Of The Upper Mississippi Embayment And Ozark Uplift, Lin Liu, Stephen S. Gao, Kelly H. Liu, Kevin Lee Mickus

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Upper Mississippi Embayment (UME), where the seismically active New Madrid Seismic Zone resides, experienced two phases of subsidence commencing in the Late Precambrian and Cretaceous, respectively. To provide new constraints on models proposed for the mechanisms responsible for the subsidence, we computed and stacked P-to-S receiver functions recorded by 49 USArray and other seismic stations located in the UME and the adjacent Ozark Uplift and modeled Bouguer gravity anomaly data. The inferred thickness, density, and Vp/Vs of the upper and lower crustal layers suggest that the UME is characterized by a mafic and high-density upper crustal …


Quantum Griffiths Phase Inside The Ferromagnetic Phase Of Ni₁₋ₓvₓ, Ruize Wang, Adane Gebretsadik, Sara Ubaid-Kassis, Almut Schroeder, Thomas Vojta, For Full List Of Authors, See Publisher's Website. Jun 2017

Quantum Griffiths Phase Inside The Ferromagnetic Phase Of Ni₁₋ₓvₓ, Ruize Wang, Adane Gebretsadik, Sara Ubaid-Kassis, Almut Schroeder, Thomas Vojta, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We study by means of bulk and local probes the d-metal alloy Ni1-xVx close to the quantum critical concentration, xc ≈ 11.6%, where the ferromagnetic transition temperature vanishes. The magnetization-field curve in the ferromagnetic phase takes an anomalous power-law form with a nonuniversal exponent that is strongly x dependent and mirrors the behavior in the paramagnetic phase. Muon spin rotation experiments demonstrate inhomogeneous magnetic order and indicate the presence of dynamic fluctuating magnetic clusters. These results provide strong evidence for a quantum Griffiths phase on the ferromagnetic side of the quantum phase transition.


Gw170104: Observation Of A 50-Solar-Mass Binary Black Hole Coalescence At Redshift 0.2, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Jun 2017

Gw170104: Observation Of A 50-Solar-Mass Binary Black Hole Coalescence At Redshift 0.2, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We describe the observation of GW170104, a gravitational-wave signal produced by the coalescence of a pair of stellar-mass black holes. The signal was measured on January 4, 2017 at 10 11:58.6 UTC by the twin advanced detectors of the Laser Interferometer Gravitational-Wave Observatory during their second observing run, with a network signal-to-noise ratio of 13 and a false alarm rate less than 1 in 70 000 years. The inferred component black hole masses are 31.2-6.0+8.4M⊙ and 19.4-5.9+5.3M⊙ (at the 90% credible level). The black hole spins are best constrained through measurement of the effective …


Search For Gravitational Waves From Scorpius X-1 In The First Advanced Ligo Observing Run With A Hidden Markov Model, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Jun 2017

Search For Gravitational Waves From Scorpius X-1 In The First Advanced Ligo Observing Run With A Hidden Markov Model, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

Results are presented from a semicoherent search for continuous gravitational waves from the brightest low-mass X-ray binary, Scorpius X-1, using data collected during the first Advanced LIGO observing run. The search combines a frequency domain matched filter (Bessel-weighted F-statistic) with a hidden Markov model to track wandering of the neutron star spin frequency. No evidence of gravitational waves is found in the frequency range 60-650 Hz. Frequentist 95% confidence strain upper limits, h095%=4.0 x 10-25, 8.3 x 10-25, and 3.0 x 10-25 for electromagnetically restricted source orientation, unknown polarization, and circular …


Lensing Is Low: Cosmology, Galaxy Formation Or New Physics?, Alexie Leauthaud, Shun Saito, For Full List Of Authors, See Publisher's Website. Jun 2017

Lensing Is Low: Cosmology, Galaxy Formation Or New Physics?, Alexie Leauthaud, Shun Saito, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We present high signal-to-noise galaxy-galaxy lensing measurements of the Baryon Oscillation Spectroscopic Survey constant mass (CMASS) sample using 250 deg2 of weak-lensing data from Canada-France-Hawaii Telescope Lensing Survey and Canada-France-Hawaii Telescope Stripe 82 Survey. We compare this signal with predictions from mock catalogues trained to match observables including the stellar mass function and the projected and twodimensional clustering of CMASS. We show that the clustering of CMASS, together with standard models of the galaxy-halo connection, robustly predicts a lensing signal that is 20-40 per cent larger than observed. Detailed tests show that our results are robust to a variety …


Microstrip Diplexer With Low Channel-Frequency Ratio, Kirti Dhwaj, Li (Lijun) Jun Jiang, Tatsuo Itoh May 2017

Microstrip Diplexer With Low Channel-Frequency Ratio, Kirti Dhwaj, Li (Lijun) Jun Jiang, Tatsuo Itoh

Electrical and Computer Engineering Faculty Research & Creative Works

The paper presents a microstrip diplexer constructed by joining two stub-perturbed ring resonators at a T-junction. Each ring resonator acts as a bandpass filter with a transmission zero lying very close to the passband of the other filter, thereby increasing the isolation between the two channels. A short stub is additionally added at the T-junction to improve the matching at the common port. The diplexer is able to achieve a channel separation of 50 MHz, with the two channels centered at 2.49 GHz and 2.37 GHz respectively. This translates to a center frequency ratio of 1.05 between the two channels, …


Nanostructured Dielectric Materials For High Energy Density Multi Layer Ceramic Capacitors, Fatih Dogan May 2017

Nanostructured Dielectric Materials For High Energy Density Multi Layer Ceramic Capacitors, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

A high energy density multilayer ceramic capacitor, having at least two electrode layers and at least one substantially dense polycrystalline dielectric layer positioned therebetween. The at polycrystalline dielectric layer has an average grain size of less than about 300 nanometers, a particle size distribution of between about 150 nanometers and about 3 micrometers, and a maximum porosity of about 1 percent. The dielectric layer is selected from the group including TiO2, BaTiO3, Al2O3, ZrO2, lead zirconium titanate, and combinations thereof and has a breakdown strength of at least about 1100 …


Precoder Design For Simultaneous Wireless Information And Power Transfer With Finite-Alphabet Inputs, Xiaodong Zhu, Weiliang Zeng, Chengshan Xiao May 2017

Precoder Design For Simultaneous Wireless Information And Power Transfer With Finite-Alphabet Inputs, Xiaodong Zhu, Weiliang Zeng, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we investigate the mutual information maximization for a multiple-input multiple-output (MIMO) system with simultaneous wireless information and power transfer (SWIPT), where perfect channel state information (CSI) is known at the transmitter. We formulate an optimization problem under the constraints of transmit power and harvested energy. Different from previous work, we assume the input signals to be taken from finite-alphabet inputs instead of Gaussian signals. The formulated problem is NP-hard, so a global optimal solution cannot be found with polynomial time complexity. However, by exploiting the structure of the problem, this optimization problem can be transformed into a …


Quantum Dynamical Response Of Ultracold Few-Boson Ensembles In Finite Optical Lattices To Multiple Interaction Quenches, J. Neuhaus-Steinmetz, Simeon I. Mistakidis, P. Schmelcher May 2017

Quantum Dynamical Response Of Ultracold Few-Boson Ensembles In Finite Optical Lattices To Multiple Interaction Quenches, J. Neuhaus-Steinmetz, Simeon I. Mistakidis, P. Schmelcher

Physics Faculty Research & Creative Works

The Correlated Nonequilibrium Quantum Dynamics Following A Multiple Interaction Quench Protocol For Few-Bosonic Ensembles Confined In Finite Optical Lattices Is Investigated. The Quenches Give Rise To An Interwell Tunneling And Excite The Cradle And A Breathing Mode. Several Tunneling Pathways Open During The Time Interval Of Increased Interactions, While Only A Few Occur When The System Is Quenched Back To Its Original Interaction Strength. The Cradle Mode, However, Persists During And In Between The Quenches, While The Breathing Mode Possesses Distinct Frequencies. The Occupation Of Excited Bands Is Explored In Detail Revealing A Monotonic Behavior With Increasing Quench Amplitude And …


Biomaterials For Local, Controlled Drug Delivery To The Injured Spinal Cord, Alexis M. Ziemba, Ryan J. Gilbert May 2017

Biomaterials For Local, Controlled Drug Delivery To The Injured Spinal Cord, Alexis M. Ziemba, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Affecting approximately 17,000 new people each year, spinal cord injury (SCI) is a devastating injury that leads to permanent paraplegia or tetraplegia. Current pharmacological approaches are limited in their ability to ameliorate this injury pathophysiology, as many are not delivered locally, for a sustained duration, or at the correct injury time point. With this review, we aim to communicate the importance of combinatorial biomaterial and pharmacological approaches that target certain aspects of the dynamically changing pathophysiology of SCI. After reviewing the pathophysiology timeline, we present experimental biomaterial approaches to provide local sustained doses of drug. In this review, we present …


The Missouri Miner, May 4, 2017 May 2017

The Missouri Miner, May 4, 2017

The Missouri Miner Newspaper

No abstract provided.


Automated Scientifically Controlled Screening Systems (Ascss), Nathan W. Twyman, Jay F. Nunamaker May 2017

Automated Scientifically Controlled Screening Systems (Ascss), Nathan W. Twyman, Jay F. Nunamaker

Business and Information Technology Faculty Research & Creative Works

The ability to detect when a person is hiding important information has high value in many applications. A new class of systems, termed autonomous scientifically controlled screening systems (ASCSS), is designed to detect individuals' purposely hidden information about target topics of interest. ASCSS represents a systematic synthesis of structured interviewing, orienting theory, defensive response theory, non-invasive psychophysiological measurement, and behavioral measurement. To evaluate and enhance the design principles, an automated screening kiosk (ASK) system was constructed. The ASK system has been used in a physical security screening scenario in which participants constructed and attempted to smuggle a fake improvised explosive …


Oscillation Criteria For Third-Order Nonlinear Functional Difference Equations With Damping, Martin Bohner, C. Dharuman, R. Srinivasan, Ethiraju Thandapani May 2017

Oscillation Criteria For Third-Order Nonlinear Functional Difference Equations With Damping, Martin Bohner, C. Dharuman, R. Srinivasan, Ethiraju Thandapani

Mathematics and Statistics Faculty Research & Creative Works

In this paper, we obtain some new criteria for the oscillation of certain third-order difference equations using comparison principles with a suitable couple of first-order difference equations. The presented results improve and extend the earlier ones. Examples are provided to illustrate the main results.


Scholars' Mine Quick Facts May 2017, James Roger Weaver May 2017

Scholars' Mine Quick Facts May 2017, James Roger Weaver

Scholars’ Mine Statistics

Scholars' Mine statistical quick facts for May 2017.


Intensity Control Of Individual Dbd Plasma Filament. I. Experiment With A Needle Electrode, M. C. Paliwoda, J. L. Rovey May 2017

Intensity Control Of Individual Dbd Plasma Filament. I. Experiment With A Needle Electrode, M. C. Paliwoda, J. L. Rovey

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Filamentary volume dielectric barrier discharge (DBD) produces patterned plasma structures that are currently being explored for reconfigurable metamaterial applications. In this work, the presence and intensity of a single filament (within an array of filaments) are controlled by biasing a low voltage needle electrode by less than 7% of the driving voltage. The current, voltage, and time-averaged normalized light intensity were measured while varying the needle voltage through self-biasing resistors. For a 7.5 kV, 3.2 kHz DBD in air, the needle-controlled filament intensity varies from 80% to 0% of the light intensity of surrounding filaments. When the biased voltage prevents …


Infrared Metasurfaces Created With Off-Normal Incidence Microsphere Photolithography, Chuang Qu, Edward C. Kinzel May 2017

Infrared Metasurfaces Created With Off-Normal Incidence Microsphere Photolithography, Chuang Qu, Edward C. Kinzel

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Fabricating metasurfaces over large areas at low costs remains a critical challenge to their practical implementation. This paper reports on the use of microsphere photolithography (MPL) to create infrared metasurfaces by changing the angle-of-incidence of the illumination to steer the photonic jet. The displacement of the photonic jet is shown to scale with the diameter of the microsphere while the exposure dose scales with the square of the microsphere diameter. This process is robust in the presence of local defects in the microsphere lattice. The paper demonstrates patterning split ring resonators and tripole based metasurfaces using MPL, which are fabricated …


Investigating Process-Structure Relations Of Zno Nanofiber Via Electrospinning Method, Ehsan Ghafari, Yining Feng, Yao Liu, Ian T. Ferguson, Na Lu May 2017

Investigating Process-Structure Relations Of Zno Nanofiber Via Electrospinning Method, Ehsan Ghafari, Yining Feng, Yao Liu, Ian T. Ferguson, Na Lu

Electrical and Computer Engineering Faculty Research & Creative Works

1D ZnO nanofibers were fabricated in this study using the electrospinning method through sol-gel approach. The effects of fabrication processing parameters on the nanofibers size have been systematically investigated. The higher concentration of the polymer resulted in a broader distribution of the nanofibers diameter due to non-uniform ejection of the fluid jet. The results indicated that an increase in annealing temperature resulted in a lower diameter size and more uniformity of the nanofiber due to decomposition of PVA. The DSC result confirms that an annealing temperature higher than 480 °C is required to remove the PVA and fully decompose the …


Fast Monostatic Scattering Analysis Based On Bayesian Compressive Sensing, Huan Huan Zhang, Wei E.I. Sha, Li (Lijun) Jun Jiang May 2017

Fast Monostatic Scattering Analysis Based On Bayesian Compressive Sensing, Huan Huan Zhang, Wei E.I. Sha, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

In conjugation with the method of moments, the Bayesian compressive sensing algorithm is utilized to fast analyze the monostatic electromagnetic scattering problem. Different from the orthogonal matching pursuit based compressive sensing approach that cannot determine the required measurement times, the proposed method overcomes the difficulty by adopting the Bayesian framework to recover the underlying signal. Error bars of the signal can be obtained in the recovery procedure, which offers a way to adaptively determine the number of compressive-sensing measurements.


Load Characteristics Of Wireless Power Transfer System With Different Resonant Types And Resonator Numbers, Yiming Zhang, Zhengming Zhao, Kainan Chen, Jun Fan May 2017

Load Characteristics Of Wireless Power Transfer System With Different Resonant Types And Resonator Numbers, Yiming Zhang, Zhengming Zhao, Kainan Chen, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

Wireless Power Transfer (WPT) has been the research focus and applied in many fields. Normally power is transferred wirelessly to charge the battery, which requires specific load characteristics. The load characteristics are essential for the design and operation of the WPT system. This paper investigates the load characteristics of the WPT system with different resonant types and resonator numbers. It is found that in a WPT system with series or LCL resonance under a constant voltage source, the load characteristic is determined by the number of inductors. Even number of inductors results in a constant current characteristic and odd number …


Effect Of Single Dead End Entry Inclination On Dpm Plume Dispersion, Yi Zheng, Hai Lan, Magesh Thiruvengadam, Jerry C. Tien, Ying Li May 2017

Effect Of Single Dead End Entry Inclination On Dpm Plume Dispersion, Yi Zheng, Hai Lan, Magesh Thiruvengadam, Jerry C. Tien, Ying Li

Mining Engineering Faculty Research & Creative Works

Diesel particulate matter (DPM) is a by-product from operating diesel engines. Since diesel powers are one of the major sources of energy for mobile underground mining equipment, the adverse health effects of DPM are of a great concern. This paper used computational fluid dynamics (CFD) method to study the effect of entry inclination on DPM plume distribution in a dead-end entry. An upward mining face and a downward mining face were built with a truck and a loader in loading operation close to the face area. A species transport model with incorporated buoyancy effect was used to examine the DPM …


Intensity Control Of Individual Dbd Plasma Filament. Ii. Fundamental Physical Mechanism, M. C. Paliwoda, J. L. Rovey May 2017

Intensity Control Of Individual Dbd Plasma Filament. Ii. Fundamental Physical Mechanism, M. C. Paliwoda, J. L. Rovey

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Filamentary volume dielectric barrier discharge (DBD) produces patterned plasma structures that are currently being explored for reconfigurable metamaterial applications. Previous work has demonstrated control of the presence and intensity of a single DBD plasma filament (within an array of filaments) by biasing a low voltage needle electrode. The results were attributed to redistributed charge inside the DBD due to the modified electric field created by the needle electrode. In the present work, results from a 3D electrodynamic field simulation bolster this argument. Results show that increasing needle bias voltage causes changes in the transverse electric field structure, resulting in redistribution …


Novel Complementary Metasurfaces For The Orbital Angular Momentum Generation, Menglin L.N. Chen, Li Jun Jiang, Wei E.I. Sha May 2017

Novel Complementary Metasurfaces For The Orbital Angular Momentum Generation, Menglin L.N. Chen, Li Jun Jiang, Wei E.I. Sha

Electrical and Computer Engineering Faculty Research & Creative Works

Besides amplitude, phase and polarization, wavefront is an important property of electromagnetic (EM) waves. EM waves with twisted wavefronts are known to carry orbital angular momentum (OAM). In this paper, a complementary-type metasurface is proposed to generate an OAM beam at microwave regime. Two metasurfaces that can produce OAM of order 2 and 4 are designed. By using our novel design methods, which are based on circuit model and dyadic Green's function, a high conversion efficiency has been achieved with a very low profile.