Digital Commons Network^™

Tunable Topological Photonic Crystal Waveguides, Menglin L.N. Chen, Li (Lijun) Jun Jiang, Wei E.I. Sha

Electrical and Computer Engineering Faculty Research & Creative Works

Edge states in topological photonic systems have the robust unidirectional propagation feature which originates from the topological nature of the bulk band dispersion. In this work, we propose a topological photonic crystal (PC) waveguide that is formed by introducing an air gap in an all-dielectric PC with C-{6v} symmetry. The dispersion of the line defect states is tunable by varying the width of the air gap. Based on their field distributions, the states can be classified into even- and odd-symmetric states. The even-symmetric states are found to be the nontrivial topological edge states and exhibit pseudospin-locking unidirectional propagation property. By …

Improvement Of Spice Based Esd Protection Models For I/O Protection Modeling, Amin Pak, Seyed Mostafa Mousavi, David Pommerenke, Giorgi Maghlakelidze, Yang Xu

Electrical and Computer Engineering Faculty Research & Creative Works

Modeling ESD protection using the System Efficient ESD Design (SEED) methodology enables optimal protection of an IO using TVS and external components. The success of modeling depends on the accuracy of the models. This work shows improvements to SPICE models used to characterize TVS diodes and IC I/O. The improvement is twofold. The transition phases between snapback and main current flow have been adjusted to achieve realistic waveforms for the rise times from 500 ps to 5 ns in a voltage range from Vt1 to the high current region, and complex curvatures of the IV curve are included. The model …

Data-Driven Discovery Of The Governing Equation For The Transmission Lines System, Yanming Zhang, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

Sophisticated structures in the transmission line system introduce the nonuniformity and nonlinearity, which brings the challenge for its characterization and modeling. In this work, a novel data-driven method is proposed to derive the governing partial differential equations of the transmission line. Based on the polynomial interpolation of the spatial-temporal samples of current and voltage, the time and spatial derivatives can be obtained. Then, the ridge regression algorithm is adopted to determine the active spatial differential terms from the candidate functions. Three benchmarks, the uniform and nonuniform transmission line, and a soliton generation system, are provided to demonstrate the validity of …

Vertical Profiles Of Trace Gas And Aerosol Properties Over The Eastern North Atlantic: Variations With Season And Synoptic Condition, Yang Wang, Guangjie Zheng, Michael P. Jensen, Daniel A. Knopf, Alexander Laskin, Alyssa A. Matthews, For Full List Of Authors, See Publisher's Website.

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Because of their extensive coverage, marine low clouds greatly impact the global climate. Presently, the response of marine low clouds to the changes in atmospheric aerosols remains a major source of uncertainty in climate simulations. One key contribution to this large uncertainty derives from the poor understanding of the properties and processes of marine aerosols under natural conditions and the perturbation by anthropogenic emissions. The eastern North Atlantic (ENA) is a region of persistent but diverse subtropical marine boundary layer (MBL) clouds, where cloud albedo and precipitation are highly susceptible to perturbations in aerosol properties. Here we examine the key …

Torsional Profiles Of Thiophene And Furan Oligomers: Probing The Effects Of Heterogeneity And Chain Length, Morgan A. Perkins, Laura M. Cline, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

A systematic analysis of the torsional profiles of 55 unique oligomers composed of two to four thiophene and/or furan rings (n = 2 to 4) has been conducted using three density functional theory (DFT) methods along with MP2 and three different coupled-cluster methods. Two planar or quasi-planar minima were identified for each n = 2 oligomer system. In every case, the torsional angle (τ) between the heteroatoms about the carbon-carbon bond connecting the two rings is at or near 180° for the global minimum and 0° for the local minimum, referred to as anti and syn conformations, respectively. These oligomers …

Off-Axis Microsphere Photolithography Patterned Nanohole Array And Other Structures On An Optical Fiber Tip For Glucose Sensing, Jiayu Liu, Ibrahem Jasim, Tao Liu, Jie Huang, Edward Kinzel, Mahmoud Almasri

Electrical and Computer Engineering Faculty Research & Creative Works

Microsphere photolithography (MPL) using off-axis UV exposure is a technique that uses a layer of self-assembled microspheres as an optical mask to project different periodic nanopatterns. This paper introduces MPL as an alternative fabrication technique to pattern complex metasurfaces on an optical single mode fiber tip as a sensor for measuring refractive index. Based on the hexagonal close packing microsphere array, complicated metasurfaces were successfully created by changing the UV illumination angle. Using the same self-assembled microspheres monolayer, multiple UV illumination jets were projected to create multiple hole group patterns. Fiber sensors with three-hole group and four-hole group patterns were …

Structural And Biochemical Characterization Of The Flavin-Dependent Siderophore-Interacting Protein From Acinetobacter Baumannii, Hannah Valentino, David A. Korasick, Tabbetha J. Bohac, Justin A. Shapiro, Timothy A. Wencewicz, John J. Tanner, Pablo Sobrado

Chemistry Faculty Research & Creative Works

Acinetobacter baumannii is an opportunistic pathogen with a high mortality rate due to multi-drug-resistant strains. The synthesis and uptake of the iron-chelating siderophores acinetobactin (Acb) and preacinetobactin (pre-Acb) have been shown to be essential for virulence. Here, we report the kinetic and structural characterization of BauF, a flavin-dependent siderophore-interacting protein (SIP) required for the reduction of Fe (III) bound to Acb/pre-Acb and release of Fe(II). Stopped-flow spectrophotometric studies of the reductive half-reaction show that BauF forms a stable neutral flavin semiquinone intermediate. Reduction with NAD(P)H is very slow (kobs, 0.001 s-1) and commensurate with the rate of reduction by photobleaching, …

Upper Limits On The Isotropic Gravitational-Wave Background From Advanced Ligo And Advanced Virgo's Third Observing Run, R. Abbott, T. D. Abbott, S. Abraham, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We report results of a search for an isotropic gravitational-wave background (GWB) using data from Advanced LIGO's and Advanced Virgo's third observing run (O3) combined with upper limits from the earlier O1 and O2 runs. Unlike in previous observing runs in the advanced detector era, we include Virgo in the search for the GWB. The results of the search are consistent with uncorrelated noise, and therefore we place upper limits on the strength of the GWB. We find that the dimensionless energy density Ω_GW ≤ 5.8 x 10^-9 at the 95% credible level for a flat (frequency-independent) GWB, …

Search For Anisotropic Gravitational-Wave Backgrounds Using Data From Advanced Ligo And Advanced Virgo's First Three Observing Runs, R. Abbott, T. D. Abbott, S. Abraham, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We report results from searches for anisotropic stochastic gravitational-wave backgrounds using data from the first three observing runs of the Advanced LIGO and Advanced Virgo detectors. For the first time, we include Virgo data in our analysis and run our search with a new efficient pipeline called pystoch on data folded over one sidereal day. We use gravitational-wave radiometry (broadband and narrow band) to produce sky maps of stochastic gravitational-wave backgrounds and to search for gravitational waves from point sources. A spherical harmonic decomposition method is employed to look for gravitational-wave emission from spatially-extended sources. Neither technique found evidence of …

Entity Retrieval Using Fine-Grained Entity Aspects, Shubham Chatterjee, Laura Dietz

Computer Science Faculty Research & Creative Works

Using entity aspect links, we improve upon the current state-of-the-art in entity retrieval. Entity retrieval is the task of retrieving relevant entities for search queries, such as "Antibiotic Use in Livestock". Entity aspect linking is a new technique to refine the semantic information of entity links. For example, while passages relevant to the query above may mention the entity "USA", there are many aspects of the USA of which only few, such as "USA/Agriculture", are relevant for this query. By using entity aspect links that indicate which aspect of an entity is being referred to in the context of the …

Search For Gravitational Waves Associated With Gamma-Ray Bursts Detected By Fermi And Swift During The Ligo-Virgo Run O3a, R. Abbott, T. D. Abbott, S. Abraham, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We search for gravitational-wave transients associated with gamma-ray bursts (GRBs) detected by the Fermi and Swift satellites during the first part of the third observing run of Advanced LIGO and Advanced Virgo (2019 April 1 15:00 UTC-2019 October 1 15:00 UTC). A total of 105 GRBs were analyzed using a search for generic gravitational-wave transients; 32 GRBs were analyzed with a search that specifically targets neutron star binary mergers as short GRB progenitors. We find no significant evidence for gravitational-wave signals associated with the GRBs that we followed up, nor for a population of unidentified subthreshold signals. We consider several …

A Kinetic Model For Blood Biomarker Levels After Mild Traumatic Brain Injury, Sima Azizi, Daniel B. Hier, Blaine Allen, Tayo Obafemi-Ajayi, Gayla R. Olbricht, Matthew S. Thimgan, Donald C. Wunsch

Mathematics and Statistics Faculty Research & Creative Works

Traumatic brain injury (TBI) imposes a significant economic and social burden. The diagnosis and prognosis of mild TBI, also called concussion, is challenging. Concussions are common among contact sport athletes. After a blow to the head, it is often difficult to determine who has had a concussion, who should be withheld from play, if a concussed athlete is ready to return to the field, and which concussed athlete will develop a post-concussion syndrome. Biomarkers can be detected in the cerebrospinal fluid and blood after traumatic brain injury and their levels may have prognostic value. Despite significant investigation, questions remain as …

Scholars' Mine Quick Facts June 2021, Nancy S. Krost

Scholars’ Mine Statistics

Scholars' Mine Quick Facts are monthly reports of downloads, page hits, and other information about works in the institutional repository of Missouri S&T. A map with downloads by region is also included.

Modeling, Analysis, And Control Design Of A Single-Stage Boost Inverter, Md Rasheduzzaman, Poria Fajri, Jonathan W. Kimball, Brad Deken

Electrical and Computer Engineering Faculty Research & Creative Works

A single-phase, single-stage, differential boost inverter comprises two independently-controlled boost DC-DC converters, with the load connected between their outputs. The net voltage on the load is sinusoidal and has a controllable frequency and magnitude that is larger than that of the DC source. The present work first derives steady-state and small-signal models of the inverter with parasitic elements. The results obtained from the line-to-output transfer function, control-to-output transfer function, open-loop input impedance, and open-loop output impedance models are compared with that of the ones obtained from the experimental testbed. Using the new models, a voltage mode controller is designed in …

Comparing Behavioral Theories To Predict Consumer Interest To Participate In Energy Sharing, Julia Morgan, Casey I. Canfield

Engineering Management and Systems Engineering Faculty Research & Creative Works

Consumer investment in distributed energy resources (DERs) is increasing the penetration of renewable energy in the grid. In some cases, DERs produce more electricity than needed by the owner and this excess electricity is sold to the utility (e.g., net metering). In contrast, energy sharing allows a facilitator, which may or may not be the utility, to redistribute excess renewable electricity to fellow community members directly. However, little is known about consumer interest in participating in this type of arrangement. This preregistered study uses structural equation modeling to compare two behavioral theories, Value-Belief-Norm and Diffusion of Innovation, to predict consumer …

Missouri S&T Magazine Summer 2021, Missouri S&T Marketing And Communications Department, Miner Alumni Association

Missouri S&T Magazine

No abstract provided.

Review Of Expansive And Collapsible Soil Volume Change Models Within A Unified Elastoplastic Framework, Sandra L. Houston, Xiong Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Numerous laboratory tests on unsaturated soils revealed complex volume-change response to reduction of soil suction, resulting in early development of state surface approaches that incorporate soil expansion or collapse due to wetting under load. Nonetheless, expansive and collapsible soils are often viewed separately in research and practice, resulting in development of numerous constitutive models specific to the direction of volume change resulting from suction decrease. In addition, several elastoplastic models, developed primarily for collapse or expansion, are modified by add-on, such as multiple yield curves/ surfaces, to accommodate a broader range of soil response. Current tendency to think of unsaturated …

An American Physiological Society Cross-Journal Call For Papers On “Inter-Organ Communication In Homeostasis And Disease”, Sue C. Bodine, Heddwen L. Brooks, Nigel W. Bunnett, Hilary A. Coller, Mark R. Frey, Bina Joe, Thomas R. Kleyman, Merry L. Lindsey, Andre Marette, Rory E. Morty, Jan Marino Ramírez, Morten B. Thomsen, Gina L.C. Yosten

Biological Sciences Faculty Research & Creative Works

No abstract provided.

Achieving Domestic Internationalization And Global Competence Through On-Campus Activities And Globally Responsive Education, Sanjay Tewari, Peng Zhang, Yuan Zhuang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The impacts of the COVID-19 pandemic on students and educators are well known. However, there is a paucity of literature available on its impact on educational institutions in the context of their abilities to develop global competence in the middle of an ongoing pandemic. The virtual communication and remote delivery of educational content have been a popular trend for many universities to adapt to the pandemic challenges and re-think their internationalization strategies.

The limited travel opportunities because of the pandemic have highlighted a big need for the domestic internationalization mechanism at educational institutions. In this paper, the authors discuss how …

Numerical Investigation Of The Thermo-Hydraulic Performance Of Water-Based Nanofluids In A Dimpled Channel Flow Using Al₂O₃, Cuo, And Hybrid Al₂O₃-Cuo As Nanoparticles, Farid Ahmed, Md Atrehar Abir, Muhtasim Fuad, Farhana Akter, Palash K. Bhowmik, Syed B. Alam, Dinesh Kumar

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

In this study, the authors study the impact of spherical dimple surfaces and nanofluid coolants on heat transfer and pressure drop. The main objective of this paper is to evaluate the thermal performance of nanofluids with respect to different Reynolds numbers (Re) and nanoparticle compositions in dimpled channel flow. Water-based nanofluids with Al₂O₃, CuO, and Al₂O₃-CuO nanoparticles are considered for this investigation with 1%, 2%, and 4% volume fraction for each nanofluid. The simulations are conducted at low Reynolds numbers varying from 500 to 1250, assuming constant and uniform heat flux. The …

Random Packing Material In Disinfection Contactors: Effects On Baffling And Energy Loss, Jessica L. Baker, Subhas K. Venayagamoorthy, Susan K. De Long

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigates the potential improvement in the hydraulic disinfection efficiency and the possible energy loss as a result of the presence of random packing material (RPM) in a laboratory-scale chlorine contactor. Tracer tests were conducted on a 55-gal drum tank filled with RPM in varying amounts in different configurations to measure the efficiency of each setup in terms of baffling factor (BF). The bulk pressure drop was measured to determine the energy loss for each configuration. The results of this study show that securing RPM near the inlet, in any amount, improves the BF by 300% to more than …

Erratum: Characterizing Permanent Deformation Of Alaskan Granular Base-Course Materials (Journal Of Materials In Civil Engineering Doi: 10.1061/(Asce)Mt.1943-5533.0002911), Jenny Liu, Xiong Zhang, Lin Li, Peng Li, Steve Saboundjian

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The writers would like to express their appreciation to the discusser for taking time to read this paper and provide his insightful viewpoint. The writers are in general agreement with the discusser's comments and this closure allows them to further clarify some of the statements in the original paper. Frost Heave and Change of Moisture Conditions after a Freezing Process The writers appreciate the discusser's further explanation and elaboration of results presented in Table 1 and Figs. 5 and 8. Permanent Deformation Modeling The writers agree with the discusser that the R2 values of Eqs. (2) – (4) in the …

Effect Of Team Cohesion Nn Flow: An Empirical Study Of Team-Based Gamification For Enterprise Resource Planning Systems In Online Classes, Yu Zhao, Mark Srite, Sumin Kim, Jinwoong Lee

Business and Information Technology Faculty Research & Creative Works

Pedagogy using gamification has recently received much attention as a way of enhancing student learning and retention. Additionally, academic institutions are making extensive use of online resources to expand teaching beyond the traditional classroom setting. Both academic institutions and companies utilize virtual teams to accomplish remote teamwork, particularly in a post-COVID environment. Despite the growing interest in incorporating gamification into teaching for business school courses, prior researchers have paid little attention to team-based gamification in the online learning environment. The purpose of this study is to examine if team members' perceived team cohesion influences their perceptions of flow. Also, we …

Vibronic Coherence And Quantum Beats Of O₂⁺ Based On Laser Pump-Probe Dissociation Dynamics, Shan Xue, Shengjun Yue, Hongchuan Du, Bitao Hu, Anh-Thu Le

Physics Faculty Research & Creative Works

We report theoretical investigations of vibronic quantum beats (QBs) which can be observed in the molecular dissociation under the intense infrared (IR) laser pump-IR laser probe scheme. We show how the vibronic coherences can be probed by analyzing the interchannel QB signals obtained from the numerical solution of the time-dependent Schrödinger equation (TDSE) and the quantum Liouville equation in combination with the strong-field approximation for the treatment of coherences between multiple states of the target ion. The validities of our methods are first tested on a one-dimensional model of H₂⁺, for which exact solutions of the TDSE …

Observation Of Gravitational Waves From Two Neutron Star-Black Hole Coalescences, R. Abbott, T. D. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We report the observation of gravitational waves from two compact binary coalescences in LIGO's and Virgo's third observing run with properties consistent with neutron star-black hole (NSBH) binaries. The two events are named GW200105_162426 and GW200115_042309, abbreviated as GW200105 and GW200115; the first was observed by LIGO Livingston and Virgo and the second by all three LIGO-Virgo detectors. The source of GW200105 has component masses 8.9^+1.2_-1.5 and 1.9^+.03_-.02 M_⊙, whereas the source of GW200115 has component masses and 5.7^+1.8_-2.1 and 1.5^+0.7_-0.3 M_⊙ (all measurements quoted at the 90% credible …

Antimatter Free-Fall Experiments And Charge Asymmetry, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

We propose a method by which one could use modified antimatter gravity experiments in order to perform a high-precision test of antimatter charge neutrality. The proposal is based on the application of a strong, external, vertically oriented electric field during an antimatter free-fall gravity experiment in the gravitational field of the Earth. The proposed experimental setup has the potential to drastically improve the limits on the charge-asymmetry parameter ɛq of antimatter. On the theoretical side, we analyze possibilities to describe a putative charge-asymmetry of matter and antimatter, proportional to the parameters ɛq and ɛq, by Lagrangian methods. We found that …

Campbell Penetration Depth In Low Carrier Density Superconductor Yptbi, Hyunsoo Kim, Makariy A. Tanatar, Halyna Hodovanets, Kefeng Wang, Johnpierre Paglione, Ruslan Prozorov

Physics Faculty Research & Creative Works

Magnetic penetration depth, λ_m, was measured as a function of temperature and magnetic field in single crystals of low carrier density superconductor YPtBi by using a tunnel-diode oscillator technique. Measurements in zero DC magnetic field yield London penetration depth, λ_L(T), but in the applied field the signal includes the Campbell penetration depth, λ_C(T), which is the characteristic length of the attenuation of small excitation field, H_AC, into the Abrikosov vortex lattice due to its elasticity. Whereas the magnetic field dependent λ_C exhibit λ_C ~ B^P with p = 1/2 …

Erratum: Laser-Induced Electron Diffraction Of The Ultrafast Umbrella Motion In Ammonia (Struct. Dyn. (2021) 8 (014301) Doi: 10.1063/4.0000046), B. Belsa, K. Amini, X. Liu, A. Sanchez, T. Steinle, J. Steinmetzer, Anh-Thu Le, R. Moshammer, T. Pfeifer, J. Ullrich, R. Moszynski, C. D. Lin, S. Gräfe, J. Biegert

Physics Faculty Research & Creative Works

This article was originally published online on 13 January 2021 with an affiliation for J. Ullrich, Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany, omitted. All online versions of the article were corrected on 13 May 2021. All affiliations appear correctly above.

A Novel Demultiplexing Scheme For Vortex Beams In Radio Communication Systems, Yanming Zhang, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

The orbital angular momentum (OAM) based communication is a promising technology in the wireless communication system for its improving spectrum efficiency. However, for the OAM demultiplexing, it requires a very large aperture size in the receiving end due to the OAM beam divergence and the amplitude null in the beam center, which restricts the full development of OAM based communication. In this paper, we propose a novel partial arc sampling receiving (PASR) scheme based on the augmented dynamic mode decomposition (ADMD) to solve this issue. We explore the use of the phase delay coordinates in the conventional DMD to sort …

Outcomes Of Training In Smart Home Technology Adoption: A Living Laboratory Study, David Wright, Daniel Burton Shank, Thomas Yarbrough

English and Technical Communication Faculty Research & Creative Works

While various forms of smart home technology have been available for decades, they have yet to achieve widespread adoption. Although they have risen in popularity during recent years, the general public continue to rate smart home devices as overly complex compared to their benefits. This article reports the results of an eight-month study into the effects of training on smart home technology adoption. Building upon the results of a previous study, and using the same living laboratory approach, we studied the effects of training on the attitudes of a group of residents toward use of smart home technology. Results show …