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The Structure And Properties Of Zinc Aluminophosphate Glasses, Charmayne E. Smith (Lonergan), Richard K. Brow, Lionel Montagne, Bertrand Revel Feb 2014

The Structure And Properties Of Zinc Aluminophosphate Glasses, Charmayne E. Smith (Lonergan), Richard K. Brow, Lionel Montagne, Bertrand Revel

Materials Science and Engineering Faculty Research & Creative Works

The glass forming region of the ZnO-Al2O3-P2O5 (ZAP) system was determined and the structures and properties of the glasses were characterized. For glasses with a constant O/P ratio, i.e., with similar average phosphate anion distributions, and with increasing alumina content, there is an increase in molar volume and glass transition temperature and a decrease in density and refractive index. The structures of the ZAP glasses were characterized by Raman spectroscopy, 31P and 27Al magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy, and high pressure liquid chromatography (HPLC). Systematically shorter phosphate …


The Missouri Miner, February 13, 2014 Feb 2014

The Missouri Miner, February 13, 2014

The Missouri Miner Newspaper

No abstract provided.


Exploring Demand Flexibility In Heterogeneous Aggregators: An Lmp-Based Pricing Scheme, Chenye Wu, Yiyu Shi, Soummya Kar Feb 2014

Exploring Demand Flexibility In Heterogeneous Aggregators: An Lmp-Based Pricing Scheme, Chenye Wu, Yiyu Shi, Soummya Kar

Electrical and Computer Engineering Faculty Research & Creative Works

With the proposed penetration of electric vehicles and advanced metering technology, the demand side is foreseen to play a major role in flexible energy consumption scheduling. On the other hand, the past several years has witnessed utility companies' growing interests to integrate more renewable energy resources. These renewable resources, for example, wind or solar, due to their intermittent nature, brought great uncertainty to the power grid system. In this article, we propose a mechanism that attempts to mitigate the grid operational uncertainty induced by renewable energies by properly exploiting demand flexibility with the help of advanced smart-metering technology. To address …


An Injectable, Calcium Responsive Composite Hydrogel For The Treatment Of Acute Spinal Cord Injury, Christopher A. Mckay, Rebecca D. Pomrenke, Joshua S. Mclane, Nicholas J. Schaub, Elise K. Desimone, Lee A. Ligon, Ryan J. Gilbert Feb 2014

An Injectable, Calcium Responsive Composite Hydrogel For The Treatment Of Acute Spinal Cord Injury, Christopher A. Mckay, Rebecca D. Pomrenke, Joshua S. Mclane, Nicholas J. Schaub, Elise K. Desimone, Lee A. Ligon, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Immediately following spinal cord injury, further injury can occur through several secondary injury cascades. As a consequence of cell lysis, an increase in extracellular Ca2+ results in additional neuronal loss by inducing apoptosis. Thus, hydrogels that reduce extracellular Ca2+ concentration may reduce secondary injury severity. The goal of this study was to develop composite hydrogels consisting of alginate, chitosan, and genipin that interact with extracellular Ca2+ to enable in situ gelation while maintaining an elastic modulus similar to native spinal cord (∼1000 Pa). It was hypothesized that incorporation of genipin and chitosan would regulate hydrogel electrostatic characteristics …


Plant Translocation Of Organic Compounds: Molecular And Physicochemical Predictors, Matt A. Limmer, Joel Gerard Burken Feb 2014

Plant Translocation Of Organic Compounds: Molecular And Physicochemical Predictors, Matt A. Limmer, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Root-Soil Boundary Represents One of the Largest Global Biotic-Abiotic Mass-Transfer Interfaces and is a Primary Pollutant Entry Point to the Food Chain. This Interface is Also Critically Important in Phytoremediation Efforts and Herbicide Design. Experimental Data and Single-Parameter Models Have Resulted in the Current Understanding that Moderately Hydrophobic Organic Compounds Are Most Likely to Be Translocated by Plants, Although Recent Evidence Indicates Plants Can Also Translocate Some Hydrophilic Compounds. Molecular Descriptors Initially Applied for Drug Discovery and for Transmembrane Migration in Mammalian Systems Were Applied Here to Determine the Physicochemical Domains and Weighted Desirability Functions to Identify Compounds Amenable …


The Origin Of Interferometric Effect Involving Surface Plasmon Polariton In Scattering Near-Field Scanning Optical Microscopy, Yan Li, Nan Zhou, Edward C. Kinzel, Xifeng Ren, Xianfan Xu Feb 2014

The Origin Of Interferometric Effect Involving Surface Plasmon Polariton In Scattering Near-Field Scanning Optical Microscopy, Yan Li, Nan Zhou, Edward C. Kinzel, Xifeng Ren, Xianfan Xu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Scattering near-field scanning optical microscopy (s-NSOM) has been developed to characterize optical near field with spatial resolution on the order of 10 nm. In this work we report investigation of the interferometric patterns commonly occurred in s-NSOM measurements. To reveal the origin of such interference patterns, a simple nano slit is used. Comparing the measured result with a simplified analytical model as well as full-field numerical simulations, it is shown that the interference pattern is predominantly formed by the in-plane component of incidence light and surface plasmon polariton (SPP) launched by the nano slit. This result helps to understand the …


Catalytic Hydrogen Transfer Of Ketones Over Atomic Layer Deposited Highly-Dispersed Platinum Nanoparticles Supported On Multi-Walled Carbon Nanotubes, Chengjun Jiang, Xinhua Liang Feb 2014

Catalytic Hydrogen Transfer Of Ketones Over Atomic Layer Deposited Highly-Dispersed Platinum Nanoparticles Supported On Multi-Walled Carbon Nanotubes, Chengjun Jiang, Xinhua Liang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Hydrogen transfer of ketones, catalyzed by highly dispersed platinum nanoparticles supported on multi-walled carbon nanotubes (MWCNTs), was studied. Pt nanoparticles were deposited on gram quantities of non-functionalized MWCNTs by atomic layer deposition (ALD) at 300 C, using (methylcyclopentadienyl) trimethylplatinum and oxygen as precursors. TEM analysis showed that ~ 1.4 nm Pt nanoparticles were highly dispersed on MWCNTs. The heterogeneous hydrogen-transfer reactions of acetophenone indicated that an acetophenone conversion of 100% and a 1-phenylethanol selectivity of 99.0% could be obtained with a ketone to Pt mass ratio of 24,690 and a ketone to KOH mass ratio of 22 at 150 C …


The Missouri Miner, February 6, 2014 Feb 2014

The Missouri Miner, February 6, 2014

The Missouri Miner Newspaper

No abstract provided.


Communicating In A Socially-Aware Network: Impact Of Relationship Types, Basak Guler, Burak Varan, Kaya Tutuncuoglu, Mohamed Nafea, Ahmed A. Zewail, Aylin Yener, Damien Octeau Feb 2014

Communicating In A Socially-Aware Network: Impact Of Relationship Types, Basak Guler, Burak Varan, Kaya Tutuncuoglu, Mohamed Nafea, Ahmed A. Zewail, Aylin Yener, Damien Octeau

Electrical and Computer Engineering Faculty Research & Creative Works

Communication networks are linked to and influenced by human interactions. Socially aware systems should integrate these complex relationship patterns in the network design. This paper studies the impact of friendship and antagonistic relationships between individuals on optimal network propagation policies. We develop a network propagation model for signed networks and determine the optimal policies to influence a target node with an opinion while minimizing the total number of persons against it. We also provide extensions to this problem to elaborate on the impact of network parameters, such as minimum-delay propagation, while limiting the number of persons influenced against the idea …


Nanostructured Dielectric Materials For High Energy Density Multilayer Ceramic Capacitors, Fatih Dogan, Alan Devoe, Ian Burn Feb 2014

Nanostructured Dielectric Materials For High Energy Density Multilayer Ceramic Capacitors, Fatih Dogan, Alan Devoe, Ian Burn

Materials Science and Engineering Faculty Research & Creative Works

A multilayer ceramic capacitor, having a plurality of electrode layers and a plurality of substantially titanium dioxide dielectric layers, wherein each respective titanium dioxide dielectric layer is substantially free of porosity, wherein each respective substantially titanium dioxide dielectric layer is positioned between two respective electrode layers, wherein each respective substantially titanium dioxide dielectric layer has an average grain size of between about 200 and about 400 nanometers, wherein each respective substantially titanium dioxide dielectric layer has maximum particle size of less than about 500 nanometers. Typically, each respective substantially titanium dioxide dielectric layer further includes at least one dopant selected …


Nanostructured Dielectric Materials For High Energy Density Multilayer Ceramic Capacitors, Fatih Dogan, Alan Devoe, Ian Burns Feb 2014

Nanostructured Dielectric Materials For High Energy Density Multilayer Ceramic Capacitors, Fatih Dogan, Alan Devoe, Ian Burns

Materials Science and Engineering Faculty Research & Creative Works

A multilayer ceramic capacitor, having a plurality of electrode layers and a plurality of substantially titanium dioxide dielectric layers, wherein each respective titanium dioxide dielectric layer is substantially free of porosity, wherein each respective substantially titanium dioxide dielectric layer is positioned between two respective electrode layers, wherein each respective substantially titanium dioxide dielectric layer has an average grain size of between about 200 and about 400 nanometers, wherein each respective substantially titanium dioxide dielectric layer has maximum particle size of less than about 500 nanometers. Typically, each respective substantially titanium dioxide dielectric layer further includes at least one dopant selected …


Oscillatory Behavior Of Solutions Of Third-Order Delay And Advanced Dynamic Equations, Murat Adivar, Elvan Akin, Raegan Higgins Feb 2014

Oscillatory Behavior Of Solutions Of Third-Order Delay And Advanced Dynamic Equations, Murat Adivar, Elvan Akin, Raegan Higgins

Mathematics and Statistics Faculty Research & Creative Works

In this paper, we consider oscillation criteria for certain third-order delay and advanced dynamic equations on unbounded time scales. A time scale T is a nonempty closed subset of the real numbers. Examples will be given to illustrate some of the results.


Improving The Hydraulics Of Drinking Water Contact Tanks Using Random Packing Material, Taylor C. Barnett, Justin J. Kattnig, Subhas K. Venayagamoorthy, Gordon Whittaker Feb 2014

Improving The Hydraulics Of Drinking Water Contact Tanks Using Random Packing Material, Taylor C. Barnett, Justin J. Kattnig, Subhas K. Venayagamoorthy, Gordon Whittaker

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigated the use of industrial packing material for increasing the hydraulic efficiency of small-scale, chlorine contact tanks used in drinking water treatment. The packing material used in the study was spherical, with porosities between 0.9 and 0.95 and a density less than that of water. A total of 67 tracer studies, conducted on laboratory-scale chlorine contact tank systems, investigated three sizes of packing material, two tank sizes, and two flow rates. Sodium chloride solution was injected as a continuous tracer and was monitored in the tank outflow through electrical conductivity. Several studies were validated with the use and …


An Event-Based Simulation Framework To Examine The Response Of Power Grid To The Charging Demand Of Plug-In Hybrid Electric Vehicles, Zahra Darabi, Mehdi Ferdowsi Feb 2014

An Event-Based Simulation Framework To Examine The Response Of Power Grid To The Charging Demand Of Plug-In Hybrid Electric Vehicles, Zahra Darabi, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes the development of a discrete-event simulation framework that emulates the interactions between the power grid and plug-in hybrid electric vehicles (PHEVs) and examines whether the capacity of the existing power system can meet the PHEV load demand. The probability distribution functions for the arrival time and energy demand of each vehicle are extracted from real-world statistical transportation data. The power grid's limited generation and transmission capacities are considered to be the major constraints. Therefore, vehicles may have to wait to receive any charge. The proposed simulation framework is justified and described in some detail in applying it …


Femtosecond And Nanosecond Dual-Laser Optical Emission Spectroscopy Of Gas Mixtures, Cheng Hsiang Lin, Zhi Liang, Jun Zhou, Hai-Lung Tsai Feb 2014

Femtosecond And Nanosecond Dual-Laser Optical Emission Spectroscopy Of Gas Mixtures, Cheng Hsiang Lin, Zhi Liang, Jun Zhou, Hai-Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A Method Employing an Integrated Femtosecond (Fs) and Nanosecond (Ns) Dual-Laser System Was Developed to Generate Plasma with Desired Radical Species from Gas Mixtures Via a Fs Laser Pulse and Then to Excite Selected Radical Species to Higher Electronic States using a Wavelength-Tunable Ns Laser Pulse. an Optical Spectrometer Was Used to Measure the Emission Spectra and Identify the Transition from the Excited Electronic State to the Ground State. the Proposed Technique Has Been Demonstrated for an N2-CO2 Mixture with Various Time Delays between the Two Fs and Ns Pulses. the Results Have Indicated that the Population of Selected Radical …


First Searches For Optical Counterparts To Gravitational-Wave Candidate Events, M. Constancio Jr., Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Feb 2014

First Searches For Optical Counterparts To Gravitational-Wave Candidate Events, M. Constancio Jr., Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

During the Laser Interferometer Gravitational-wave Observatory and Virgo joint science runs in 2009-2010, gravitational wave (GW) data from three interferometer detectors were analyzed within minutes to select GW candidate events and infer their apparent sky positions. Target coordinates were transmitted to several telescopes for follow-up observations aimed at the detection of an associated optical transient. Images were obtained for eight such GW candidates. We present the methods used to analyze the image data as well as the transient search results. No optical transient was identified with a convincing association with any of these candidates, and none of the GW triggers …


The Bridge Newsletter Spring 2014, Missouri University Of Science And Technology Feb 2014

The Bridge Newsletter Spring 2014, Missouri University Of Science And Technology

The Bridge Newsletter

-Reusing scrap tires
-Renaissance man
-Energy research published
-Follow your passion


Enhanced Glt-1 Mediated Glutamate Uptake And Migration Of Primary Astrocytes Directed By Fibronectin-Coated Electrospun Poly-L-Lactic Acid Fibers, Jonathan M. Zuidema, María C. Hyzinski-García, Kristien Van Vlasselaer, Nicholas W. Zaccor, George E. Plopper, Alexander A. Mongin, Ryan J. Gilbert Feb 2014

Enhanced Glt-1 Mediated Glutamate Uptake And Migration Of Primary Astrocytes Directed By Fibronectin-Coated Electrospun Poly-L-Lactic Acid Fibers, Jonathan M. Zuidema, María C. Hyzinski-García, Kristien Van Vlasselaer, Nicholas W. Zaccor, George E. Plopper, Alexander A. Mongin, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bioengineered fiber substrates are increasingly studied as a means to promote regeneration and remodeling in the injured central nervous system (CNS). Previous reports largely focused on the ability of oriented scaffolds to bridge injured regions and direct outgrowth of axonal projections. In the present work, we explored the effects of electro spun microfibers on the migration and physiological properties of brain astroglial cells. Primary rat astrocytes were cultured on either fibronectin-coated poly-l-lactic acid (PLLA) films, fibronectin-coated randomly oriented PLLA electro spun fibers, or fibronectin-coated aligned PLLA electro spun fibers. Aligned PLLA fibers strongly altered astrocytic morphology, orienting cell processes, actin …


Modeling The Construction Of Polymeric Adsorbent Media: Effects Of Counter-Ions On Ligand Immobilization And Pore Structure, Enrico Riccardi, Jee-Ching Wang, Athanasios I. Liapis Feb 2014

Modeling The Construction Of Polymeric Adsorbent Media: Effects Of Counter-Ions On Ligand Immobilization And Pore Structure, Enrico Riccardi, Jee-Ching Wang, Athanasios I. Liapis

Chemical and Biochemical Engineering Faculty Research & Creative Works

Molecular dynamics modeling and simulations are employed to study the effects of counter-ions on the dynamic spatial density distribution and total loading of immobilized ligands as well as on the pore structure of the resultant ion exchange chromatography adsorbent media. The results show that the porous adsorbent media formed by polymeric chain molecules involve transport mechanisms and steric resistances which cause the charged ligands and counter-ions not to follow stoichiometric distributions so that (i) a gradient in the local nonelectroneutrality occurs, (ii) non-uniform spatial density distributions of immobilized ligands and counter-ions are formed, and (iii) clouds of counter-ions outside the …


Energy Efficiency And Spectral Efficiency Tradeoff In Type-I Arq Systems, Jingxian Wu, Gang Wang, Yahong Rosa Zheng Feb 2014

Energy Efficiency And Spectral Efficiency Tradeoff In Type-I Arq Systems, Jingxian Wu, Gang Wang, Yahong Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

The optimum energy efficient and spectral efficient designs for type-I automatic-repeat-request (ARQ) systems in Rayleigh flat fading channels are studied in this paper. Three optimum designs are considered: the first scheme maximizes the energy efficiency (EE), or equivalently, minimizes the total energy per information bit without considering the spectral efficiency (SE); the second scheme minimizes a new metric, the energy per information bit normalized by the SE; and the third scheme maximizes the EE under the constraint of a minimum SE. For given physical and link layer parameters, such as hardware power consumption, coding rate, modulation, bit rate, number of …


Spectral Induced Polarization (Sip) Response Of Biodegraded Oil In Porous Media, Gamal Z. Abdel Aal, Estella A. Atekwana Feb 2014

Spectral Induced Polarization (Sip) Response Of Biodegraded Oil In Porous Media, Gamal Z. Abdel Aal, Estella A. Atekwana

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Laboratory experiments were conducted to investigate the effect of different oil saturation (0.2- 0.8), wetting conditions (water-wet and oil-wet), and the addition of asphaltene on the spectral induced polarization (SIP) response of biodegraded and fresh crude oil in sand columns. In the water-wet case, no significant differences were observed for both the fresh and biodegraded oil and both displayed an increase in the magnitude of the phase (φ) and decrease in the magnitudes of the real (σ′) and imaginary (σ″) conductivity components with increasing oil saturation. In this instance the SIP response is most likely controlled by the conduction and …


Multiphase Hydrodynamics And Distribution Characteristics In A Monolith Bed Measured By Optical Fiber Probe, Yuan Zhou, Milorad P. Dudukovic, Muthanna H. Al-Dahhan, Hui Liu Feb 2014

Multiphase Hydrodynamics And Distribution Characteristics In A Monolith Bed Measured By Optical Fiber Probe, Yuan Zhou, Milorad P. Dudukovic, Muthanna H. Al-Dahhan, Hui Liu

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Optical Fiber Probe Has Been for the First Time Applied to Investigate the Hydrodynamics and Gas-Phase Distribution at High Gas/liquid Ratios in a Two-Phase Flow Monolith Bed with 0.048 M Diameter and 400 Cpsi. Local Hydrodynamic Parameters Including Gas Holdup, Bubble Frequency, Bubble Velocity, and Bubble Length in Single Channels Were Measured by 16 Inserted Single-Point Optical Fiber Probes within the Bed under a Nozzle as the Liquid Distributor. the Following Findings Are Reported. (1) the Optical Fiber Probe Can Be Used as an Efficient and Convenient Technique for Measuring Local Hydrodynamic Parameters Inside the Channels of a Monolith …


Criticality And Quenched Disorder: Harris Criterion Versus Rare Regions, Thomas Vojta, José A. Hoyos Feb 2014

Criticality And Quenched Disorder: Harris Criterion Versus Rare Regions, Thomas Vojta, José A. Hoyos

Physics Faculty Research & Creative Works

We employ scaling arguments and optimal fluctuation theory to establish a general relation between quantum Griffiths singularities and the Harris criterion for quantum phase transitions in disordered systems. If a clean critical point violates the Harris criterion, it is destabilized by weak disorder. At the same time, the Griffiths dynamical exponent z' diverges upon approaching the transition, suggesting unconventional critical behavior. In contrast, if the Harris criterion is fulfilled, power-law Griffiths singularities can coexist with clean critical behavior, but z' saturates at a finite value. We present applications of our theory to a variety of systems including quantum spin chains, …


Role Of Electron Saddle Swaps In The Photon Spectra Following Li³⁺ Charge-Exchange Collisions With H*(N = 2), Na(3s), Na*(3p), And Li(2s) Targets, Sebastian Otranto, R. Hoekstra, Ronald E. Olson Feb 2014

Role Of Electron Saddle Swaps In The Photon Spectra Following Li³⁺ Charge-Exchange Collisions With H*(N = 2), Na(3s), Na*(3p), And Li(2s) Targets, Sebastian Otranto, R. Hoekstra, Ronald E. Olson

Physics Faculty Research & Creative Works

The role of electron saddle swaps in collisions of bare Li with metastable hydrogen and alkali-metal atoms is investigated by means of the classical trajectory Monte Carlo method. In particular, we show that oscillations as a function of collision energy in the photon spectra resulting from charge exchange are directly related to the number of potential-saddle crossings that a receding electron can achieve during a given reaction. The range of impact energies spanned is 0.01-50 keV/amu, an area of interest for diagnostic purposes in tokamak nuclear fusion power reactors.


Multi-Terminal Networks With An Untrusted Relay, Ahmed A. Zewail, Mohamed Nafea, Aylin Yener Jan 2014

Multi-Terminal Networks With An Untrusted Relay, Ahmed A. Zewail, Mohamed Nafea, Aylin Yener

Electrical and Computer Engineering Faculty Research & Creative Works

This paper investigates the impact of cooperation with an untrusted relay in multi-source multi-destination networks. The set up considered is one where the relay is the only means of communications due to the absence of direct links between the sources and the destinations. Since the relay is untrusted, all messages from the sources need to be kept secret from the relay. Furthermore, the destinations are assumed to have different levels of security clearance, i.e., some private messages should only be decoded by their intended receiver and should be kept secret from other destinations. An achievable secure rate region is found …


Faculty Senate Minutes January 23, 2014, Missouri University Of Science And Technology Faculty Senate Jan 2014

Faculty Senate Minutes January 23, 2014, Missouri University Of Science And Technology Faculty Senate

Minutes & Agendas

No abstract provided.


Environmental Stress Cracking Of Glassy Polymers, Parthasakha Neogi, Gholamreza Zahedi Jan 2014

Environmental Stress Cracking Of Glassy Polymers, Parthasakha Neogi, Gholamreza Zahedi

Chemical and Biochemical Engineering Faculty Research & Creative Works

When a glassy polymer is exposed to an organic solvent, it can crack spontaneously or fail more readily under extension. This is environmental stress cracking. When the solvent diffuses into the polymer, stresses develop because of swelling of the polymer. In addition, fluctuations give rise to stresses, because of the variation in surface tension from changes in the surface concentration of the solute, which is the Marangoni effect. A linear stability analysis is performed to show that such a system is unstable to infinitesimal disturbances. Large tensile stresses arise locally, leading to failures, which will be observed in the interfacial …


Model-Free Q-Learning Over Finite Horizon For Uncertain Linear Continuous-Time Systems, Hao Xu, S. Jagannathan Jan 2014

Model-Free Q-Learning Over Finite Horizon For Uncertain Linear Continuous-Time Systems, Hao Xu, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel optimal control over finite horizon has been introduced for linear continuous-time systems by using adaptive dynamic programming (ADP). First, a new time-varying Q-function parameterization and its estimator are introduced. Subsequently, Q-function estimator is tuned online by using both Bellman equation in integral form and terminal cost. Eventually, near optimal control gain is obtained by using the Q-function estimator. All the closed-loop signals are shown to be bounded by using Lyapunov stability analysis where bounds are functions of initial conditions and final time while the estimated control signal converges close to the optimal value. The simulation …


Event-Based Optimal Regulator Design For Nonlinear Networked Control Systems, Avimanyu Sahoo, Hao Xu, S. Jagannathan Jan 2014

Event-Based Optimal Regulator Design For Nonlinear Networked Control Systems, Avimanyu Sahoo, Hao Xu, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel stochastic event-based near optimal control strategy to regulate a networked control system (NCS) represented as an uncertain nonlinear continuous time system. An online stochastic actor-critic neural network (NN) based approach is utilized to achieve the near optimal regulation in the presence of network constraints, such as, network induced time-varying delays and random packet losses under event-based transmission of the feedback signals. The transformed nonlinear NCS in discrete-time after the incorporation the delays and packet losses are utilized for the actor-critic NN based controller design. To relax the knowledge of the control coefficient matrix, a NN …


Neural Network-Based Adaptive Optimal Consensus Control Of Leaderless Networked Mobile Robots, Haci Mehmet Guzey, Hao Xu, S. Jagannathan Jan 2014

Neural Network-Based Adaptive Optimal Consensus Control Of Leaderless Networked Mobile Robots, Haci Mehmet Guzey, Hao Xu, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

A novel neural network (NN)-based optimal adaptive consensus control scheme is introduced in this paper for networked mobile robots in the presence of unknown robot dynamics. Throughout the paper, two NNs are used. The unknown formation dynamics of each robot is identified by using the first NN. The second NN is utilized to approximate a novel value function derived in this paper as a function of augmented error vector, which is comprised of the regulation and consensus-based formation errors of each robot. A novel near optimal controller is developed by using approximated value function and identified formation dynamics. The Lyapunov …