Engineering Commons^™

Legends As A Device For Interacting With Visualizations, Mihail E. Tudoreanu, Eileen Kraemer

All Computer Science and Engineering Research

Users and developers of visualization tools must deal with the problem of specifying what information to show and how to represent it. Typically, the user's focus of interest will change over time, and the specifications must change with the user's interests. Techniques for the simple, direct, and intuitive creation and refinement of these specifications can be useful. In this paper we show how legends, a natural element of graphical displays, may be used as a direct and unobstrusive interaction device through which users may interactively specify new visualizations and animations.

Services Provision In Ad Hoc Networks, Radu Handorean, Gruia-Catalin Roman

All Computer Science and Engineering Research

The client-server model continues to dominate distributed computing with increasingly more flexible variants being deployed. Many are centered on the notion of discovering services at run time and on allowing any system component to act as a service provider. The result is a growing reliance on the service registration and discovery mechanisms. This paper addresses the issue of facilitating such service provision capabilities in the presence of (logical and physical) mobility exhibited by applications executing over ad hoc networks. The solution being discussed entailes a new kind of service model, which we were able to build as an adaption layer …

Magnetic Nanoparticles And Nanoparticle Assemblies From Metallorganic Precursors, Suresh Pillai, Yurri Gunko, David Mcinerney

Articles

No abstract provided.

Fatigue Assessment Of Traffic Signal Mast Arms Based On Field Test Data Under Natural Wind Gusts, Genda Chen, Jingning Wu, Jiaqing Yu, Lokeswarappa R. Dharani, Michael G. Barker

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In recent years, several states including Missouri, Wyoming, California, and Texas experienced fracture failures of traffic signal mast arms. Almost all the failures are associated with the propagation of defects or cracks. It is therefore imperative to evaluate existing mast arms using a simple yet accurate procedure. A statistical methodology is proposed to predict the fatigue life of signal mast arm structures on the basis of field-measured strain data. The annual occurrence of various stress levels is determined using the historical wind speed data in the vicinity of a mast arm structure and the strain readings of the structure under …

An Efficient Instruction Cache Scheme For Object-Oriented Languages, Yul Chu, M. R. Ito

Electrical and Computer Engineering Faculty Publications

We present an efficient cache scheme, which can considerably reduce instruction cache misses caused by procedure call/returns. This scheme employs N-way banks and XOR mapping functions. The main function of this scheme is to place a group of instructions separated by a call instruction into a bank according to the initial and final bank selection mechanisms. After the initial bank selection mechanism selects a bank on an instruction cache miss, the final bank selection mechanism will determine the final bank for updating a cache line as a correction mechanism. These two mechanisms can guarantee that recent groups of instructions exist …

Robust Adaptive Critic Based Neurocontrollers For Missiles With Model Uncertainties, Zhongwu Huang, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A Lyapunov theory-based controller is proposed in this paper for robustness against model uncertainties in the control of a missile. The controller design consists of two parts; in the first phase, an optimal nonlinear controller is designed with neural networks for tracking. This is based on the adaptive critic method that consists of one neural network called the supervisor or critic and a second network called an action network or a controller. Each network is trained through the output of the other network and equations related to optimal control. When their outputs are mutually consistent, the controller network output is …

Measurements Of The Average Properties Of A Suspension Of Bubbles Rising In A Vertical Channel, Ashok S. Sangani, Roberto Zenit, Donald L. Koch

Biomedical and Chemical Engineering - All Scholarship

Experiments were performed in a vertical channel to study the behaviour of a monodisperse bubble suspension for which the dual limit of large Reynolds number and small Weber number was satisfied. Measurements of the liquid-phase velocity fluctuations were obtained with a hot-wire anemometer. The gas volume fraction, bubble velocity, bubble velocity fluctuations and bubble collision rate were measured using a dual impedance probe. Digital image analysis was performed to quantify the small polydispersity of the bubbles as well as the bubble shape.A rapid decrease in bubble velocity with bubble concentration in very dilute suspensions is attributed to the effects of …

Numerical Simulation Of A Gas–Liquid Flow In A Fixed Bed, Ashok S. Sangani, Sangkyun Koo

Biomedical and Chemical Engineering - All Scholarship

A countercurrent gas–liquid flow through a fixed bed of spherical particles is examined numerically by solving the particle-scale equations governing the gas and liquid flows. The liquid is assumed to flow along the surface of the particles forming a thin film. The case of small gas flow rates is examined in detail first. In this limit the presence of the liquid film increases the gas pressure drop over its value for a dry bed by three mechanisms: The liquid film makes the apparent size of the particles larger, decreases the pore space for the gas flow, and, with its velocity …

Focal Osteolysis At The Junctions Of A Modular Stainless-Steel Femoral Intramedullary Nail, Darron M. Jones, Lawrence Marsh, James V. Nepola, Joshua J. Jacobs, Anastasia K. Skipor, Robert M. Urban, Jeremy L. Gilbert, Josheph A. Buckwater

Biomedical and Chemical Engineering - All Scholarship

Background:

During routine follow-up of patients treated with a three-piece stainless-steel modular femoral nail, osteolysis and periosteal reaction around the modular junctions of some of the nails were noted on radiographs. The purpose of this study was to evaluate the prevalence, etiology, and clinical relevance of these radiographic findings.

Methods:

Forty-four femoral fractures or nonunions in forty-two patients were treated with a modular stainless-steel femoral intramedullary nail. Seventeen nails were excluded, leaving twenty-seven intramedullary nails in twenty-seven patients for this study. All patients had had a femoral diaphyseal fracture; nineteen had had an acute fracture and eight, a nonunion. These …

Time-Domain Electric-Field Integral Equation With Central Finite Difference, Baek Ho Jung, Tapan Kumar Sarkar

Electrical Engineering and Computer Science - All Scholarship

In this paper, we present a new formulation using the time-domain electric-field integral equation (TD-EFIE) to obtain a transient scattering response from arbitrarily shaped conducting bodies. The time derivative of the magnetic vector potential is approximated with a central finite difference, and the scalar potential is time averaged by dividing it into two terms. This approach with an implicit method using central-difference results in accurate and stable transient scattering responses from conducting objects. Detailed mathematical steps are included, and several numerical results are presented.

A Scalable Durable Grid Event Service, Geoffrey C. Fox, Shrideep Pallickara

Electrical Engineering and Computer Science - All Scholarship

It is interesting to study the system and software architecture of environments, which integrate the evolving ideas of computational grids, distributed objects, web services, peer-to-peer networks and message oriented middleware. Such peer-to-peer (P2P) Grids should seamlessly integrate users to themselves and to resources, which are also linked to each other. We can abstract such environments as a distributed system of "clients" which consist either of "users" or "resources" or proxies thereto. These clients must be linked together in a flexible fault tolerant efficient high performance fashion. In this paper, we study the messaging or event system -- termed GES or …

Amplitude Modulated Droplet Formation In High Precision Solder Droplet Printing, Qingbin Liu, M. Orme, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

There are many methods used at present to apply solder to wafers, ceramics, laminate and flex circuit boards, and other substrates. Among these, high-precision solder droplet printing technology, which is noncontact, data driven, flexible and environmentally friendly, is a key enabling technology. This technology selectively deposits solder droplets only where required, and therefore needs no mask or secondary resist removal, uses materials more efficiently and creates less waste than other methods. Currently, continuous droplet formation from capillary streams is mainly achieved by application of the well-known Rayleigh instability in which a sinusoidal disturbance is applied to the stream, resulting in …

Development Of Transparent Lsco And Lscno Conductors For Optical Shutter Systems, Robert W. Schwartz, M. T. Sebastian, M. Charoenwongsa, H. D. Dobberstein

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We have prepared lanthanum strontium cobalt oxide (La0.50Sr0.50CoO3; LSCO 50/50) and lanthanum strontium cobalt nickel oxide (La0.50Sr0.50Co0.50Ni0.50O3; LSCNO) as candidate transparent electrodes for use in a shutter-based infrared sensor protection device. The shutter device requires that the electrode be transparent (80% transmission) and have moderate sheet resistance (300 Ω/sq.). Because of the effects of film thickness on intrinsic material properties, such as resistivity and extinction coefficient, and simple engineering issues (i.e., the relationship between film thickness, resistance and transmission), films of various thicknesses were prepared to achieve an optimal balance of electrical and optical performance. van der Pauw measurements and …

The Problem Of A Viscoelastic Cylinder Rolling On A Rigid Half-Space, John Murrough Golden, G.A.C. Graham

Articles

The problem of a viscoelastic cylinder rolling on a rigid base, propelled by a line force acting at its centre, is solved in the noninertial approximation. The method used is based on a decomposition of hereditary integrals developed by the authors in previous work, and on the viscoelastic Kolosov-Muskhelishvili equations which are used to generate a Hilbert problem. In this formulation, the problem reduces to a nonsingular integral equation in space and time, which simplifies under steady-state conditions and for exponential decay materials, to algebraic form. There are also two subsidiary conditions.

In the case of a standard linear model, …

Measurement And Monitoring Of Microwave Reflection And Transmission Properties Of Cement-Based Materials For Propagation Modeling, Sergey Kharkovsky, U. C. Hasar, M. F. Akay, C. D. Atis

Electrical and Computer Engineering Faculty Research & Creative Works

A non-destructive, contactless, free-space method is used for measuring and monitoring the properties of cement-based materials. We analyse the propagation factor, penetration depth and reflection and transmission coefficients of the plane wave interacting with the highly lossy specimen. Results are presented of the measurement and monitoring of the properties of cement-based materials during all stages of their lives and different curing conditions The expected applications of the results for propagation modelling are discussed.

Robust Control Of Input Limited Smart Structural Systems, Sridhar Sana, Vittal S. Rao

Electrical and Computer Engineering Faculty Research & Creative Works

Integration of controllers with smart structural systems require the controllers to consume less power and to be small in hardware size. These requirements pose as limits on the control input and the order of the controllers. Use of reduced order model of the plant in the controller design can cause spill over problems in the closed-loop system due to possible excitation of the unmodeled dynamics. In this paper, we present a method to design output feedback robust controllers for smart structures in the presence of control input limits considering unmodeled dynamics as additive uncertainty in the design. The performance requirements …

A Continually Online Trained Neurocontroller For Excitation And Turbine Control Of A Turbogenerator, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

A Statistical Solution To A Text Decoding Challenge Problem, Xindi Cai, Rui Xu, Donald C. Wunsch, V. A. Samaranayake

Electrical and Computer Engineering Faculty Research & Creative Works

Given an encoded unknown text message in the form of a three dimensional spatial series generated by the use of four smooth nonlinear functions, we use a method based on simple statistical reasoning to pick up samples for rebuilding the four functions. The estimated functions are then used to decode the sequence. The experimental results show that our method gives a nearly perfect decoding, enabling us to submit a 100% accurate solution to the IJCNN challenge problem

Adaptive Critic Based Neuro-Observer, Xin Liu, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A new Neural Network (NN) based observer design method for nonlinear systems represented by nonlinear dynamics and linear/nonlinear measurement is proposed in this paper. In this new approach, as the first step, the observer design problem is changed into a "controller" design problem by establishing the error dynamics, and then the Adaptive Critic (AC) based approach is applied on this error dynamics to design a 'controller', such that the errors are driven to zero. The resulting observer has inherent robustness from the AC based design approach. Some simulations are presented to illustrate the effectiveness of this approach.

Whispering Gallery Mode Dielectric Resonators For The Millimeter Wave Near Field Sensing Applications, Sergey Kharkovsky, Yu Prokopenko, M. F. Akay

Electrical and Computer Engineering Faculty Research & Creative Works

The resonance characteristics of whispering gallery modes (WGMs) in parallel-plate type cylindrical dielectric resonators (DRs) are numerically considered to optimise their characteristics for sensing applications. Results for the dependency of the resonant frequency, Q-factor, slow-down factor and electric energy filling factor of the modes on resonator parameters for both isotropic and anisotropic DR are presented. The possible applications of the results for millimeter wave near field nondestructive measurements are discussed.

A Parallel Computer-Go Player, Using Hdp Method, Donald C. Wunsch, Xindi Cai

Electrical and Computer Engineering Faculty Research & Creative Works

The game of Go has simple rules to learn but requires complex strategies to play well, and, the conventional tree search algorithm for computer games is not suited for Go program. Thus, the game of Go is an ideal problem domain for machine learning algorithms. This paper examines the performance of a 19x19 computer Go player, using heuristic dynamic programming (HDP) and parallel alpha-beta search. The neural network based Go player learns good Go evaluation functions and wins about 30% of the games in a test series on 19x19 board

Reducing Power Bus Impedance At Resonance With Lossy Components, Todd H. Hubing, Theodore M. Zeeff

Electrical and Computer Engineering Faculty Research & Creative Works

Power bus structures in printed circuit boards with solid power and ground planes exhibit resonances. When the power bus is resonant, the power bus impedance can increase dramatically. This paper explores the effect of component equivalent series resistance (ESR) on power bus resonances. General guidelines for selecting an optimum ESR are provided and are supported by laboratory measurements and numerical simulations

Experiments On Adaptive Techniques For Host-Based Intrusion Detection, Timothy Draelos, Michael Collins, David Duggan, Edward Thomas, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

This research explores four experiments of adaptive host-based intrusion detection (ID) techniques in an attempt to develop systems that can detect novel exploits. The technique considered to have the most potential is adaptive critic designs (ACDs) because of their utilization of reinforcement learning, which allows learning exploits that are difficult to pinpoint in sensor data. Preliminary results of ID using an ACD, an Elman recurrent neural network, and a statistical anomaly detection technique demonstrate an ability to learn to distinguish between clean and exploit data. We used the Solaris Basic Security Module (BSM) as a data source and performed considerable …

Excitation And Turbine Neurocontrol With Derivative Adaptive Critics Of Multiple Generators On The Power Grid, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

Based on derivative adaptive critics, neurocontrollers for excitation and turbine control of multiple generators on the electric power grid are presented. The feedback variables are completely based on local measurements. Simulations on a three-machine power system demonstrate that the neurocontrollers are much more effective than conventional PID controllers, the automatic voltage regulators and the governors, for improving the dynamic performance and stability under small and large disturbances

To Research, Analyse And Install An Optimised Maintenance Management System For A Medium Sized Manufacturing Company: A Textile Company Case Study, Christopher O'Donoghue

Theses

Modern manufacturing is continually striving to ensure that products are made to higher levels of quality with faster lead times and at the lowest possible costs. Manufacturing production has never been more reliant on machines and automated processes than it is today. This thesis investigates the management philosophies that are in existence, which cater specifically for maintenance and maintenance related issues. Management philosophies such as Reliability Centred Maintenance (RCM), Total Productive Maintenance (TPM), Profit Centred Maintenance (PCM), asset management (AM), Predictive Maintenance (PdM), Condition Based Maintenance (CBM) and World Class Maintenance (WCM) have increased company profits by drastically reducing maintenance …

Electrochemical Generation Of Superoxide In Room-Temperature Ionic Liquids, Inas M. Alnashef, Matthew L. Leonard, Matthew C. Kittle, Michael A. Matthews, John W. Weidner

Faculty Publications

We have demonstrated that superoxide ion can be generated electrochemically in room-temperature ionic-liquid solvents. In the absence of impurities, cyclic voltammetry showed that the super oxide ion is stable in these solvents. Similar superoxide ion chemistry has previously been demonstrated in volatile and environmentally suspect aprotic solvents such as dimethyl formamide and acetonitrile. However, ionic liquids are nonvolatile and should minimize the problems of secondary solvent waste. It is proposed that the resultant superoxide ion can be used to perform low temperature oxidation of wastes. Low-temperature oxidation of waste solvents can provide a much needed alternative to high-temperature waste incinerators, …

Pedestrian Reaction To Crossing Signal Delay, Deogratias Eustace

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

Pedestrians with experience at a certain intersection learn the length of signal cycle, the phase change pattern of the signal, and the order in which traffic flow is released. These pedestrians have a higher chance of noncompliance with traffic signals. Most of the noncomplying pedestrians save a small amount of time, less than 18 seconds, by crossing the road shortly before the onset of the WALK signal indication. The study agrees with other studies done in the past that pedestrians ignore the traffic signals. They do so in order to reduce their own time delays.

Water Distribution Modeling, Thomas M. Walski, Donald V. Chase, Dragan A. Savic

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

To effectively use water distribution models, the engineer must be able to link knowledge of basic hydraulic theory and the mechanics of the program with that of the operation of real-world systems. Water Distribution Modeling does just that.

Written by industry experts, it provides a practical resource for engineers and modelers that goes well beyond being a how-to guide for typing data into a computer program. It contains straightforward answers to common questions related both to modeling and to distribution systems in general.

This textbook walks the practicing engineer or student through the modeling process from start to finish — …

A Framework For The Implementation Of An Iso 9000 Based Certification Program For Printed Circuit Board Manufacturers, Adam Y. Maamoun

Retrospective Theses and Dissertations

ISO 9000:2000 is the newest version of the ISO 9000 family of standards. Unlike the 1994 version, it does not distinguish between servicing, testing and designing standards. It emphasizes quality improvement rather than quality control and briefly explains how to implement the Plan-Do-Check- Act (PDCA) cycle for improvement and the use of statistical techniques to improve the quality of process and product instead of controlling the quality of the output. The thesis explains why companies need to be certified and how to implement quality improvement programs.

The objective of this thesis is to provide generic certification guidelines for printed circuit …

Spatial Patterns And Floodplain Contributions Of Mining-Related Contaminants In Chat Creek Watershed, Southwest Missouri, Jimmy Trimble

Graduate Theses/Dissertations

Past mining activities have left a legacy of water quality problems in the Tri-State Mining District. Contemporary environmental risks stem from the release of lead and zinc from mine tailings previously dispersed far downstream in alluvial deposits as well as abandoned tailings piles. This study examines mining-related heavy metal contamination in the Chat Creek Watershed. Chat Creek drains the area near Aurora, Missouri on the eastern edge of the Tri-State District where mining occurred from 1886 to about 1930. This study identifies the spatial distribution of metal contamination in fluvial sediments and quantifies the role of bank erosion as a …