Digital Commons Network^™

Reinforcement Learning Neural-Network-Based Controller For Nonlinear Discrete-Time Systems With Input Constraints, Pingan He, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

A novel adaptive-critic-based neural network (NN) controller in discrete time is designed to deliver a desired tracking performance for a class of nonlinear systems in the presence of actuator constraints. The constraints of the actuator are treated in the controller design as the saturation nonlinearity. The adaptive critic NN controller architecture based on state feedback includes two NNs: the critic NN is used to approximate the "strategic" utility function, whereas the action NN is employed to minimize both the strategic utility function and the unknown nonlinear dynamic estimation errors. The critic and action NN weight updates are derived by minimizing …

A Normalized Fractionally Lower-Order Moment Algorithm For Space-Time Adaptive Processing, Y. Rosa Zheng, Genshe Chen, Erik Blasch

Electrical and Computer Engineering Faculty Research & Creative Works

A new space-time adaptive processing algorithm is proposed for clutter suppression in phased array radar systems. In contrast to the commonly used normalized least mean square (NLMS) algorithm which uses the second order moments of the data for adaptation, the proposed method uses the lower order moments of the data to adapt the weight coefficients. The normalization is also performed based on the data sample dispersion rather than the variance. Processing results using simulated and measured data show that the proposed algorithm converges faster than the NLMS algorithms in Gaussian and non-Gaussian clutter environments. It also provides better clutter suppression …

Undergraduate And Graduate Catalog [2006-2007], Georgia Southern University

Undergraduate & Graduate Catalogs

No abstract provided.

2007 - 2008 Undergraduate Catalog, Armstrong Atlantic State University

Armstrong Office of the Registrar: Undergraduate Catalogs (Archived)

Undergraduate catalog for Armstrong Atlantic State University.

A Pitch Estimation Algorithm Based On The Smooth Harmonic Average Peak-To-Valley Envelope, Arturo Camacho, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

We propose SHAPE, a novel pitch estimation algorithm (PEA) that builds upon previous PEAs, addressing and solving some of their limitations. The SHAPE algorithm estimates the pitch using a smooth function to compute the average peak to valley distance at harmonic locations. This is done by performing an integral transform over the square-root magnitude of the spectrum using a truncated decaying cosine as a kernel. SHAPE was designed to both match human perception particularly for inharmonic sounds and to be competitive with numerous other PEAs as demonstrated on a common database. © 2007 IEEE.

Florida Wireless Implantable Recording Electrodes (Fwire) For Brain Machine Interfaces, Rizwan Bashirullah, John G. Harris, Justin C. Sanchez, Toshikazu Nishida, Jose C. Principe

Electrical and Computer Engineering Faculty Research & Creative Works

This paper reviews on-going efforts towards the development of the Florida Wireless Implantable Recording Electrodes (FWIRE). The FWIRE microsystem platform is a fully implantable flexible substrate microelectrode array that employs state-of-the-art integrate-and-fire (IF) signal representation and wireless interface circuitry for recording neural activity from behaving rodents. The modular nature of the implantable neural recording electrode allows future enhancements to be seamlessly added to improve functionality including but not limited to rechargeability through inductive coupling, custom microelectrode arrays, higher capacity batteries, and more advanced integrated circuit technologies. This paper concentrates on custom integrated circuits such as neural interfacing amplifiers, baseband signal …

Southern Educator, Georgia Southern University

College of Education: News & Publications (2003-2023)

• COE Alumna Launches One-Room School Project
• IEP Fellows at Georgia Southern
• Authentically Respecting Individuals
• Where in the World is the Center for International Schooling?
• Teaching Series for Technical Institutes
• Researcher Focuses on Inclusion Practices
• Cross-Cultural Issues Conference Held
• FIPSE Grant Project Professional Development District: P-16 Partnership for Teaching/Learning Renewal and Reducing the Achievement Gap
• PRISM Growth Noted
• Regional Social Science Fair
• Spotlight on Alumni
• Southern Educator Class Roll
• Celebrate the Achievement of 100 Years

Rfid Instrumentation In A Field Application, Theresa M. Swift, Martha J. Molander, Steve Eugene Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

The behavior of radio-frequency identification (RFID) tags is investigated in a field application. The RFID instrumentation is used to mark the position of point strain sensors in a fiber-reinforced polymer (FRP), short-span bridge. The tags are surface mounted on carbon FRP structural elements and covered with a resin wear layer, i.e. the deck of the bridge. The smart composite bridge was installed in 2000 and serves as a field testbed for various sensor technologies including the RFID tags. The operation of the RFID network is tested in the field and compared to laboratory tags. Specific research issues include long-term survivability …

Wave Propagation On Power Cables With Special Regard To Metallic Screen Design, R. Papazyan, Per Pettersson, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

The high frequency properties of coaxial power cables are modeled using time- and frequency-domain numerical simulations. This is required due to the complex helical structure of the outer metallic screen. The finite element (FEM) and finite difference time domain methods (FDTD) have been employed to study the effect of screen spiralization. It is established that this screen design causes a dependence of the cable high frequency characteristics on the surrounding medium. Analytical model based on modal analysis of wave propagation in coaxial cables confirms the numerical observations.

Online Reinforcement Learning Neural Network Controller Design For Nanomanipulation, Qinmin Yang, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel reinforcement learning neural network (NN)-based controller, referred to adaptive critic controller, is proposed for affine nonlinear discrete-time systems with applications to nanomanipulation. In the online NN reinforcement learning method, one NN is designated as the critic NN, which approximates the long-term cost function by assuming that the states of the nonlinear systems is available for measurement. An action NN is employed to derive an optimal control signal to track a desired system trajectory while minimizing the cost function. Online updating weight tuning schemes for these two NNs are also derived. By using the Lyapunov approach, …

Route Aware Predictive Congestion Control Protocol For Wireless Sensor Networks, Carl Larsen, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

Congestion in wireless sensor networks (WSN) may lead to packet losses or delayed delivery of important information rendering the WSN-based monitoring or control system useless. In this paper a routing-aware predictive congestion control (RPCC) yet decentralized scheme for WSN is presented that uses a combination of a hop by hop congestion control mechanism to maintain desired level of buffer occupancy, and a dynamic routing scheme that works in concert with the congestion control mechanism to forward the packets through less congested nodes. The proposed adaptive approach restricts the incoming traffic thus preventing buffer overflow while maintaining the rate through an …

Two Neural Network Based Decentralized Controller Designs For Large Scale Power Systems, Wenxin Liu, Jagannathan Sarangapani, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Mariesa Crow, David A. Cartes

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents two neural network (NN) based decentralized controller designs for large scale power systems' generators, one is for the excitation control and the other is for the steam valve control. Though the control signals are calculated using local signals only, the transient and overall system stabilities can be guaranteed. NNs are used to approximate the unknown and/or imprecise dynamics of the local power system and the interconnection terms, thus the requirements for exact system parameters are released. Simulation studies with a three machine power system demonstrate the effectiveness of the proposed controller designs.

Neural Network Control Of Robot Formations Using Rise Feedback, Jagannathan Sarangapani, Travis Alan Dierks

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a combined kinematic/torque control law is developed for leader-follower based formation control using backstepping in order to accommodate the dynamics of the robots and the formation in contrast with kinematic-based formation controllers that are widely reported in the literature. A neural network (NN) is introduced along with robust integral of the sign of the error (RISE) feedback to approximate the dynamics of the follower as well as its leader using online weight tuning. It is shown using Lyapunov theory that the errors for the entire formation are asymptotically stable and the NN weights are bounded as opposed …

Mobile Speed Estimation For Broadband Wireless Communications, Y. Rosa Zheng, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a new algorithm is proposed to estimate mobile speed for broadband wireless communications, which often encounter large number of fading channel taps causing severe intersymbol interference. Theoretical analysis is first derived and practical algorithm is proposed based on the analytical results. The algorithm employs a modified auto-covariance of received signal power to estimate the speed of mobiles. The algorithm is based on the received signals which contain unknown transmitted data, unknown frequency selective multipaths possibly including line-of-sight (LOS) component, and random receiver noise. The algorithm works well for frequency selective Rayleigh and Rician channels. The algorithm is …

Faculty Handbook, Georgia Southern University

Faculty Handbooks

Faculty Handbook for Georgia Southern University for the 2007-2008 academic year. The Faculty Handbook is published online by the Office of the Vice President for Academic Affairs and archived in Digital Commons@Georgia Southern.

Fighting The Freeloader Effect : Cooperation, Attitude, And Achievement In A Jesuit Secondary Math Classroom, Kevin Quattrin

Doctoral Dissertations

unavailable

Touching The Spirit As A Motivating Factor For African American Students To Achieve Academic Excellence, E'Leva D.H. Gibson

Doctoral Dissertations

unavailable

Espoused Curriculum And Philosophy And Curriculum And Philosophy-In-Use In A K-12 Public Charter School System, Elizabeth G. Polito

Doctoral Dissertations

unavailable

Damping Controllers For Power System Oscillations Using A Static Var Compensator, Sandhya R. Jetti

Masters Theses

"Damping of power system plays an important role in not only increasing the transmission capacity but also in stabilizing the power system, especially after critical faults. Static Var Compensator (SVC) is a shunt FACTS device which has capability of fast and continuous capacitive and inductive reactive power supply to the power system. SVCs are widely used for voltage stability but studies show that they are also effective in providing damping to the system. In this thesis, three types of SVC damping controllers are designed. The first damping controller is an optimal linear controller in which the parameters of a damping …

Dynamic Modeling And Simulations Of Solid Oxide Fuel Cells For Grid-Tied Applications, Nagasmitha Akkinapragada

Masters Theses

"As energy consumption rises, one must find suitable alternative means of generation to supplement conventional existing generation facilities. In this regard, distributed generation (DG) will continue to play a critical role in the energy supply-demand realm. The common technologies available as DG are micro-turbines, solar photovoltaic systems, fuel cells stack and wind energy systems. In this thesis, a dynamic model of solid oxide fuel cell (SOFC) is presented. Fuel cells operate at low voltages and hence need to be boosted and inverted in order to be connected to the utility grid. The interconnection of the SOFC with a DC-DC converter …

Towards A Methodology For Integrated Freeform Manufacturing Systems Development With A Control Systems Emphasis, Jacquelyn K. Stroble

Masters Theses

"A variety of fully integrated Freeform Fabrication (FFF) systems have been developed, a selected group for research and several for commercialization. The design methodology behind most of them is not documented, standardized, or rational. It is important to understand that the final product from any integrated system is affected not only by the unit manufacturing processes themselves, but also by the extent the individual units are assimilated into an integrated process. Thus, a scheme consisting of eight steps and the salient five elements necessary to create or retrofit an existing system to achieve an Integrated Freeform Manufacturing System (FFMS) is …

Screening New Cytokinesis Genes And Investigation Of Regulation Of Hof1 In Cytokinesis, Jung Eun Park

Masters Theses

"In 1996, a complete sequence of the budding yeast genome was completed and numerous studies begun to discover the function of genes. A primary concern of this study was to identify genes that may function in cytokinesis. Seven candidate genes were chosen, which were previously shown to localize to the bud neck, the site of cytokinesis, or interact with a protein that is involved in cytokinesis. Six of those uncharacterized genes, YHR149C, YLR187W, YOL070C, YMR124W, YPL158C, and YOR304C-A, were identified by data generated by GFP tagging of the yeast proteome. Data from a large-scale two-hybrid screen was used to identify …

Interactive And Dialogue Based Learning In Engineering Education, Siddartha Thummuri

Masters Theses

"This thesis focuses on a class room architecture that provides high levels of interactivity which enhances the students' learning environment both in distance and on-campus contexts and forms a basis for practical learning. Two analyses are presented in this thesis, the first one being a simple measure of levels of interactivity in this course architecture, based on rubric and the second one, a comparative analysis, to demonstrate the effectiveness of interactive (multi-directional information flow) classrooms as opposed to conventional (unidirectional information flow) classrooms and that this course architecture is ideal for enhancement of distance learning and an excellent route to …

An Exploratory Study Of The Videoblogger's Community, John Warmbrodt

Masters Theses

"Videoblogs (vlogs) have emerged as a new form of virtual community. The goal of this study was to explore and understand the videoblogger community by studying the community's structure and the motivations of vloggers"--Abstract, page iii.

On-Line Inspection And Thermal Properties Comparison For Laser Deposition Process, Yu Yang

Masters Theses

"This thesis is focused on comparing the laser deposition cladding with intended design model and comparing the effect of laser deposition process on thermal properties with traditional welding process. It is research on two aspects of laser deposition cladding. The first part of the thesis is aimed at solving the geometric inspection of laser deposition cladding, and the second part is for comparing the thermal properties of laser deposition cladding to samples of conventional welding process"--Introduction, page 1.

A Quantitative Study Of Gene Identification Techniques Based On Evolutionary Rationales, Cyriac Kandoth

Masters Theses

"Current gene identification (GI) techniques typically rely on matching biological or chemical properties of specific genes, specific species, specific ecotypes, etc...In this thesis, a new automated GI technique is proposed, and compared against another computer-based technique proposed earlier. Both methods utilize EST data available from NCBI databases to discover previously unknown genes. The newly proposed method identifies one gene family at a time and is based on a distinctive negative selection pattern (NSP) of differences, which is seen between the coding regions of gene family members. The other technique, called ESTminer, attempts genome-wide gene family identification for any organism, by …

Vision Based Leader-Follower Formation Control For Mobile Robots, Gerard Sequeira

Masters Theses

"Creating systems with multiple autonomous vehicles places severe demands on the design of control schemes. Robot formation control plays a vital role in coordinating robots. As the number of members in a system rise, the complexity of each member increases. There is a proportional increase in the quantity and complexity of onboard sensing, control and computation. This thesis investigates the control of a group of mobile robots consisting of a leader and several followers to maintain a desired geometric formation"--Abstract, page iii.

Cognitive Biases In Risk Management, William Thomas Siefert

Masters Theses

"This thesis contends that most Risk Management/Mitigation programs fail to be as effective as they could be due to a number of mostly overlooked drivers, such as motivation and cognitive biases. The issue of cognitive biases is very seldom addressed. When questioned, most engineers purport to not have any biases. They insist that they use only logic, reasoning, and math to make decisions. A set of data was collected and reviewed for this thesis. The data presented shows that cognitive biases do affect the risk management/mitigation process. Knowledge of these biases and their potential impact on a project will lead …

Magnetohydrodynamic Power Generation In A Scramjet Using A Post Combustor Generator, Nathan Lee Mundis

Masters Theses

"A scramjet with a post combustor MHD generator is examined. A quasi-one-dimensional model is developed to calculate the flow path from tip to tail. The model includes losses due to combustion irreversibility, incomplete combustion, chemically reacting flow, friction, MHD losses, and nozzle plume modeling. Flight Mach number, magnetic field strength, gas conductivity, MHD load factor, and MHD generator expansion angle are all varied in order to assess their effects on MHD power generated and thrust lost in the engine. The trends produced through the above variations are summarized in a set of model-fit equations. It is concluded that a post …

Cfd Simulation Of Contact Planarization, Shanti Vusirikala

Masters Theses

"Semiconductor devices form the essential components of most electronic devices. The fabrication of circuit elements to manufacture these devices is done by a process known as photolithography, using photoresist layer deposition, optical masks, and etching. As feature sizes become smaller, higher optical precision is required, necessitating an optically flat surface on the photoresist layer. The surface of the photoresist layer can become uneven because of conformation to the topography of the layers underneath or a change in shape of the layer after evaporation of solvent. To combat this, Brewer Science, Inc. has developed a contact planarization process (CON-TACT®) in which …