Digital Commons Network^™

Magnetic Control Of Lateral Migration Of Ellipsoidal Microparticles In Microscale Flows, R. Zhou, C. A. Sobecki, J. Zhang, Yanzhi Zhang, Cheng Wang

Mathematics and Statistics Faculty Research & Creative Works

No abstract provided.

Transient Heterogeneous Electromagnetic Simulation With Dgtd And Behavioral Macromodel, Huan Huan Zhang, Li (Lijun) Jun Jiang, He Ming Yao, Yu Zhang

Electrical and Computer Engineering Faculty Research & Creative Works

A novel hybrid field-circuit simulation method is proposed for transient heterogeneous electromagnetic simulations. It adopts the discontinuous Galerkin time domain (DGTD) method and behavioral macromodel trained by artificial neural network to analyze the electromagnetic structure and circuit network, respectively. Due to the feature of DGTD method and behavioral macromodel, the proposed method can handle not only electromagnetic structures with complex geometries and materials but also manage circuits with unknown internal details. It provides a new approach that has the trainable accuracy to meet today's IP projection requestions. It is also the first time for DGTD algorithm to work with the …

Identifying Corrosion Zones In Coastal Regions For Metal Pipes -- A Gis Approach, Sanjay Tewari, Francis Manning

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 paper focuses on applying readily available soil data such as spatial distribution of soil types and soil characteristics (e.g., pH and conductivity) towards creating a geospatial information system (GIS) based approach to identifying corrosion zones in the coastal regions. A combination of data, obtained from field surveys provided by the Louisiana Transportation Research Center and Web Soil …

Apparatus For Converting Direct Current To Alternating Current Using Multiple Converters, Patrick L. Chapman, Brian T. Kuhn, Robert S. Balog, Jonathan W. Kimball, Philip T. Krein, Alexander Gray

Electrical and Computer Engineering Faculty Research & Creative Works

An inverter for converting an input direct current (DC) waveform from a DC source to an output alternating current (AC) waveform for delivery to an AC grid includes an input converter, an output converter, and an active filter, each of which is electrically coupled to a bus. The bus may be a DC bus or an AC bus. The input converter is configured to convert the input DC waveform to a DC or AC bus waveform. The output converter is configured to convert the bus waveform to the output AC waveform at a grid frequency. The active filter is configured …

(E,2e) Ionization Studies Of N₂ At Low To Intermediate Energies From A Coplanar Geometry To The Perpendicular Plane, Ahmad Sakaamini, Matthew Harvey, Sadek Amami, Andrew James Murray, Don H. Madison, Chuangang Ning

Physics Faculty Research & Creative Works

Synopsis. The progress of experimental and theoretical measurements for (e,2e) ionization cross sections from Nitrogen molecules is presented. Results are given for energies from ~10 eV above the ionization potential (IP) through to ~100 eV above the IP for the 3σ_g, 1π_u and 2σ_g states.

Inverse Design Of Perfectly Transmitting Eigenchannels In Scattering Media, Milan Koirala, Raktim Sarma, Hui Cao, Alexey Yamilov

Physics Faculty Research & Creative Works

Light-matter interactions inside a turbid medium can be controlled by tailoring the spatial distribution of energy density throughout the system. Wavefront shaping allows selective coupling of incident light to different transmission eigenchannels, producing dramatically different spatial intensity profiles. In contrast to the density of transmission eigenvalues that is dictated by the universal bimodal distribution, the spatial structures of the eigenchannels are not universal and depend on the confinement geometry of the system. Here, we develop and verify a model for the transmission eigenchannel with the corresponding eigenvalue close to unity. By projecting the original problem of two-dimensional diffusion in a …

Klein Tunneling Near The Dirac Points In Metal-Dielectric Multilayer Metamaterials, L. Sun, Jie Gao, Xiaodong Yang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Realizing Structural Color Generation With Aluminum Plasmonic V-Groove Metasurfaces, W. Wang, D. Rosenmann, D. Czaplewski, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Broadband Polarization Conversion With Anisotropic Plasmonic Metasurfaces, W. Cao, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

No abstract provided.

Natural & Unnatural-Parity Contributions In Electron-Impact Ionization Of Laser-Aligned Atoms, Andrew James Murray, James Colgan, Don H. Madison, Matthew Harvey, Ahmad Sakaamini, James Pursehouse, Kate Nixon, Al Stauffer

Physics Faculty Research & Creative Works

Differential cross section measurements from laser-aligned Mg atoms are compared to theoretical calculations using both time dependent and time-independent formalisms. It is found that both natural and unnatural parity contributions to the calculated cross sections are required to emulate the data when the state is aligned out of the scattering plane.

Effects Of Iron Concentration And Redox States On Failure Of Boron-Free E-Glass Fibres Under Applied Stress In Different Conditions, Qingwei Wang, Richard K. Brow, Hong Li, Erica Ann Ronchetto

Materials Science and Engineering Faculty Research & Creative Works

Hydrolysis resistance of boron-free E-glass fiber with different total iron oxide (Fe₂O₃) concentrations, iron redox index and durations of fiber ageing up to 180 days at 50◦C with 50% relative humidity (RH) was studied. The effect of ageing on the fibre failure measured in two different test environments was examined by using two-point bending method. Based on the differences in failure strains of the fibres obtained from the two conditions as a function of ageing time, the Griffith theory of solid fracture was applied to estimate glass surface energy difference in ageing conditions. The results showed …

Secure Transmission With Large Numbers Of Antennas And Finite Alphabet Inputs, Yongpeng Wu, Jun Bo Wang, Jue Wang, Robert Schober, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we investigate secure transmission over the large-scale multiple-antenna wiretap channel with finite alphabet inputs. First, we investigate the case where instantaneous channel state information (CSI) of the eavesdropper is known at the transmitter. We show analytically that a generalized singular value decomposition (GSVD)-based design, which is optimal for Gaussian inputs, may exhibit a severe performance loss for finite alphabet inputs in the high signal-to-noise ratio regime. In light of this, we propose a novel Per-Group-GSVD (PG-GSVD) design, which can effectively compensate the performance loss caused by the GSVD design. More importantly, the computational complexity of the PG-GSVD …

On Critical Service Recovery After Massive Network Failures, Novella Bartolini, Stefano Ciavarella, Thomas F. La Porta, Simone Silvestri

Computer Science Faculty Research & Creative Works

This paper addresses the problem of efficiently restoring sufficient resources in a communications network to support the demand of mission critical services after a large-scale disruption. We give a formulation of the problem as a mixed integer linear programming and show that it is NP-hard. We propose a polynomial time heuristic, called iterative split and prune (ISP) that decomposes the original problem recursively into smaller problems, until it determines the set of network components to be restored. ISP's decisions are guided by the use of a new notion of demand-based centrality of nodes. We performed extensive simulations by varying the …

A Unified Ab Initio Approach To The Correlated Quantum Dynamics Of Ultracold Fermionic And Bosonic Mixtures, L. Cao, V. Bolsinger, Simeon I. Mistakidis, G. M. Koutentakis, S. Krönke, J. M. Schurer, P. Schmelcher

Physics Faculty Research & Creative Works

We Extent The Recently Developed Multi-Layer Multi-Configuration Time-Dependent Hartree Method For Bosons For Simulating The Correlated Quantum Dynamics Of Bosonic Mixtures To The Fermionic Sector And Establish A Unifying Approach For The Investigation Of The Correlated Quantum Dynamics Of A Mixture Of Indistinguishable Particles, Be It Fermions Or Bosons. Relying On A Multi-Layer Wave-Function Expansion, The Resulting Multi-Layer Multi-Configuration Time-Dependent Hartree Method For Mixtures (ML-MCTDHX) Can Be Adapted To Efficiently Resolve System-Specific Intra- And Inter-Species Correlations. The Versatility And Efficiency Of ML-MCTDHX Are Demonstrated By Applying It To The Problem Of Colliding Few-Atom Mixtures Of Both Bose-Fermi And Fermi-Fermi Types. …

Structural Vs.. Compositional Disorder In Thermal Conductivity Reduction Of Sige Alloys, Jihui Nie, Raghavan Ranganathan, Zhi Liang, Pawel Keblinski

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We Use Equilibrium Molecular Dynamics Simulations to Determine the Relative Role of Compositional and Structural Disorder in a Phononic Thermal Conductivity Reduction by Studying Three 50-50 SiGe Alloy Structures: Ordered Alloys, Disordered Alloys, and Amorphous Alloys, as Well as Pure Amorphous Si and Ge Structures for Reference. While Both Types of Disorders Significantly Reduce Thermal Conductivity, Structural Disorder is Much More Effective to This Aim. the Examination of Phonon Lifetimes in Disordered Alloys Shows High Values in a Low Frequency Regime Governed by Umklapp Scattering that Are Reduced Rapidly with Increasing Frequency Following Rayleigh Scattering Behavior. the Local Properties Analysis …

Workflow - Scholars' Mine Research Data Processing Workflow, James Roger Weaver

Scholars' Mine - Policies, Procedures and Guidelines

A graphic representation of the workflow utilized to process research data sets submitted to Scholars' Mine.

Singularity Formation In The Geometry Of Perturbed Shocks Of General Mach Number, Wouter Mostert, Dale I. Pullin, Ravi Samtaney, Vincent Wheatley

Mechanical and Aerospace Engineering Faculty Research & Creative Works

While planar shock waves are known to be stable to small perturbations in the sense that the perturbation amplitude decays over time, it has also been suggested that plane propagating shocks can develop singularities in some derivative of their geometry (Whitham (1974) Linear and nonlinear waves. Wiley, New York) in a nonlinear, wave reinforcement process. We present a spectral-based analysis of the equations of geometrical shock dynamics that predicts the time to singularity formation in the profile of an initially perturbed planar shock for general shock Mach number. We find that following an initially sinusoidal perturbation, the shock shape remains …

Evaluation Of Deep Learning Frameworks Over Different Hpc Architectures, Shayan Shams, Richard Platania, Kisung Lee, Seung Jong Park

Computer Science Faculty Research & Creative Works

Recent advances in deep learning have enabled researchers across many disciplines to uncover new insights about large datasets. Deep neural networks have shown applicability to image, time-series, textual, and other data, all of which are available in a plethora of research fields. However, their computational complexity and large memory overhead requires advanced software and hardware technologies to train neural networks in a reasonable amount of time. To make this possible, there has been an influx in development of deep learning software that aim to leverage advanced hardware resources. In order to better understand the performance implications of deep learning frameworks …

Cnn Based 3d Facial Expression Recognition Using Masking And Landmark Features, Huiyuan Yang, Lijun Yin

Computer Science Faculty Research & Creative Works

Automatically recognizing facial expression is an important part for human-machine interaction. In this paper, we first review the previous studies on both 2D and 3D facial expression recognition, and then summarize the key research questions to solve in the future. Finally, we propose a 3D facial expression recognition (FER) algorithm using convolutional neural networks (CNNs) and landmark features/masks, which is invariant to pose and illumination variations due to the solely use of 3D geometric facial models without any texture information. The proposed method has been tested on two public 3D facial expression databases: BU-4DFE and BU-3DFE. The results show that …

Discontinuous Galerkin Time-Domain Analysis Of Power/Ground Plate Pairs With Wave Port Excitation, Ping Li, Li (Lijun) Jun Jiang, Hakan Baǧci

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, a discontinuous Galerkin time-domain method is developed to analyze the power/ground plate pairs taking into account arbitrarily shaped antipads. To implement proper source excitations over the antipads, the magnetic surface current expanded by the electric eigen-modes supported by the corresponding antipad is employed as the excitation. For irregularly shaped antipads, the eigen-modes are obtained by numerical approach. Accordingly, the methodology for the S-parameter extraction is derived based on the orthogonal properties of the different modes. Based on the approach, the transformation between different modes can be readily evaluated.

Numerical Modeling Of Pcb Power/Ground Plate-Pairs By Dgtd Method Taking Into Account Decoupling Capacitors, Ping Li, Li (Lijun) Jun Jiang, Hakan Baǧci

Electrical and Computer Engineering Faculty Research & Creative Works

A discontinuous Galerkin time-domain (DGTD) method is proposed in this work to analyze printed circuit board (PCB) power/ground plate-pair having arbitrarily shaped anti-pads. To apply proper excitation source over the irregular anti-pad, the implemented wave port magnetic current excitation is expanded by the electric eigen-modes of the anti-pad that are calculated via either numerical approach or analytical method. Based on the orthogonality of eigen-modes, the temporal mode expansion coefficient for each mode can be conveniently extracted. Besides, considering the presence of decoupling capacitors, the whole physical system can be split into field and circuit subsystems. For the field subsystem, it …

Electromagnetic-Circuit Cosimulation Based On Hybrid Explicit-Implicit Dgtd And Sbf Macromodel, Ping Yuan, Huan Huan Zhang, Li (Lijun) Jun Jiang, Daniel Garcia Donoro, Yu Zhang

Electrical and Computer Engineering Faculty Research & Creative Works

The integrated circuits usually have multiscale feature. If utilizing the explicit discontinuous Galerkin time domain (DGTD) method for electromagnetic-circuit cosimulation, the time step size will be limited to the minimum grid size according to CFL (Courant-Friedrichs-Lewy) condition, which will lead to a small time step size. In order to improve the simulation efficiency, this paper adopts the hybrid explicit-implicit DGTD coupled with the Sigmoidal basis function (SBF) macromodel to achieve electromagnetic-circuit cosimulation.

Analytical Evaluation Of Partial Inductances With Retardation, L. Lombardi, G. Antonini, A. E. Ruehli

Electrical and Computer Engineering Faculty Research & Creative Works

The Partial Element Equivalent Circuit (PEEC) circuit oriented electromagnetic method has been found particularly useful for modeling PCBs, interconnects, and 3-D problems involving both electromagnetic computations and circuits. Efficiency improvements in PEEC for higher frequencies are becoming important especially for large aspect ratio cells. The analytical solution of the six-fold integrals has been shown to lead to a very efficient solution for such integrals. In this paper we introduce a new approach for the analytical evaluation of retarded partial inductances at arbitrary distances.

Scholars' Mine Annual Report From July 2016 - Jun 2017, James Roger Weaver

Scholars’ Mine Statistics

No abstract provided.

Scholars' Mine Quick Facts July 2017, James Roger Weaver

Scholars’ Mine Statistics

Scholars' Mine statistical quick facts for July 2017.

Analysis Of Time-Dependent Bearing Capacity Of A Driven Pile In Clayey Soils By Total Stress Method, Lin Li, Jingpei Li, De'an Sun, Weibing Gong

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This paper proposes an analytical approach to evaluate the time-dependent bearing capacity of a driven pile in clayey soils by taking the pile installation and subsequent reconsolidation effects into consideration. The process of pile installation is modeled by undrained expansion of a spherical cavity at the pile tip and a cylindrical cavity around the pile shaft. The cavity expansion solution, which is based on a K0-consolidated anisotropic modified Cam-clay model (K0-AMCC), is used to capture the pile installation effects. After pile installation, the dissipation of the excess pore water and the increase of the effective stress in the surrounding soil …

Mantle Transition Zone Discontinuities Beneath The Indochina Peninsula: Implications For Slab Subduction And Mantle Upwelling, Youqiang Yu, Stephen S. Gao, Kelly H. Liu, Ting Yang, Mei Xue, Khanhphon Le

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

While the northward indentation of the Indian into Eurasian plates has been intensively investigated, its oblique subduction beneath the Indochina Peninsula (ICP) and the role it played on mantle structure and dynamics remain enigmatic. In this first regional-scale receiver function study of the mantle transition zone (MTZ) discontinuities beneath the ICP and its surrounding areas, we stack ~12,000 receiver functions recorded at 33 stations using a non-plane wave common-conversion-point stacking technique. Systematic spatial variations of MTZ thickness with departures between -21 and +24 km from the globally averaged value are revealed, providing independent evidence for the presence of slab segments …

Solvent Based 3d Printing Of Biopolymer/Bioactive Glass Composite And Hydrogel For Tissue Engineering Applications, Krishna Kolan, Yong Liu, Jakeb Baldridge, Caroline Murphy, Julie A. Semon, D. E. Day, Ming-Chuan Leu

Biological Sciences Faculty Research & Creative Works

Three-dimensional (3D) bioprinting is an emerging technology in which scaffolding materials and cell-laden hydrogels may be deposited in a pre-determined fashion to create 3D porous constructs. A major challenge in 3D bioprinting is the slow degradation of melt deposited biopolymer. In this paper, we describe a new method for printing poly-caprolactone (PCL)/bioactive borate glass composite as a scaffolding material and Pluronic F127 hydrogel as a cell suspension medium. Bioactive borate glass was added to a mixture of PCL and organic solvent to make an extrudable paste using one syringe while hydrogel was extruded and deposited in between the PCL/borate glass …

The Role Of N-Acetylcysteine Amide In Defending Primary Human Retinal Pigment Epithelial Cells Against Tert-Butyl Hydroperoxide-Induced Oxidative Stress, Hsiu-Jen Wang, Yue-Wern Huang, Shakila B. Tobwala, Annelise Pfaff, Robert Aronstam, Nuran Ercal

Biological Sciences Faculty Research & Creative Works

Background: Age-related macular degeneration (AMD) is a leading cause of blindness in the United States among adults age 60 and older. While oxidative stress is implicated in the pathogenesis of AMD, dietary antioxidants have been shown to delay AMD progression in clinical studies. We hypothesized that N-acetylcysteine amide (NACA), a thiol antioxidant, would protect retinal pigment epithelium and impede progression of retinal degeneration.

Methods: tert-Butyl hydroperoxide (TBHP) was used to induce oxidative stress in cell cultures. The goal was to evaluate the efficacy of NACA in an in vitro model of AMD in primary human retinal pigment epithelial cells …

Synthesis, Characterization And Photocatalytic Activity Of Ag Metallic Particles Deposited Carbon-Doped Tio2 Nanocomposites Supported On Stainless Steel Mesh, J. O. Tijani, T. C. Totito, O. O. Fatoba, O. O. Babajide, L. F. Petrik

Mining Engineering Faculty Research & Creative Works

Abstract: In this present work, post deposition of metallic Ag nanoparticles on carbon-doped TiO₂ nanocomposites supported on stainless steel mesh was achieved via a combination of sol–gel and thermal evaporation techniques. Poly acrylonitrile dissolved in dimethyl formamide, and titanium tetra chloride was used as a carbon and titanium precursor, respectively. The photocatalytic activity of the prepared supported catalysts was evaluated by the degradation of an aqueous solution of methylene blue as a model pollutant under ultra-violet light irradiation. The prepared photocatalysts were characterized by several analytical techniques such as high resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, Brunauer–Emmett–Teller …