Engineering Commons^™

Adjustable Ice Fishing Tip-Up, Ashok Midha

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An ice fishing tip-up includes a base frame adapted to span a hole in a layer of ice over a body of water, and carrying a mast which is extendible through the hole into the water. The mast includes a shaft fixed at its lower end to a spool of fishing line and at its upper end to a cam cylinder with a helical groove formed in its outer surface. A signal staff is spring-biased to a raised position and is movable to a lowered position received in one of the convolutions of the helical groove. A pull on the …

Cell Mapping Based Fuzzy Control Of Car Parking, Tea-Quin Kim, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper describes the development of a near-optimal fuzzy controller for maneuvering a car in a parking lot. To generate the rules of the fuzzy controller, a cell mapping method is utilized to systematically generate near-optimal trajectories for all possible initial states in the parking lot. Based on the input-output relations of these trajectories, which represent the states and controls of the corresponding cells, a set of fuzzy rules are generated automatically. In order to result in a small number of fuzzy rules from the large amount of numerical information generated by cell mapping, grouping of trajectories is proposed and …

Modeling Partially Premixed Fast Chemical Reactions In Statistically Homogeneous Turbulent Flow Using One-Dimensional Equations Of Change, Yang Gi Kim, X. B. Reed

Chemical and Biochemical Engineering Faculty Research & Creative Works

A pseudospectral algorithm has been used to compute solutions u(x,t), Ax,t), B(x,t), and R(x,t) to one-dimensional equations of change incorporating the simple reaction A + B → R for statistically homogeneous random velocity and partially premixed reactant concentration fields. An initial turbulence Reynolds number of 400 has been used, together with Damkohler numbers of 102 and 103 for fast reactions and Schmidt numbers of 10-3, 1, and 102 to span a wide range of diffusivities. Evolving concentration profiles inform intuition in general and provide insight into the evolution of the single-point statistical measures in particular: (A), (B), (a2), (b2), (ab), …

Acid Characteristics Of Dissolved Organic Matter In Wastewater, Jianmin Wang, C. P. Huang, Herbert E. Allen, Luis R. Takiyama, Ira Poesponegoro, Haryanto Poesponegoro, Dan Pirestani

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The presence of dissolved organic matter (DOM) in a wastewater treatment system can significantly affect the uptake of heavy metals by sludge particulates. The characteristics of DOM, its concentration, and the solution pH are important parameters governing the heavy metals uptake reaction. The characteristics of DOM of various wastewater and sludge (primary, secondary, and tertiary) samples collected from four municipal wastewater treatment plants were investigated. Results showed that the dissolution of DOM from sludge is significantly affected by pH and suspended solids concentration. Results also showed that DOM contains two discrete acid groups that are available for metals complexation. The …

Gaseous Cah Removal By Biofiltration In Presence And Absence Of A Nonionic Surfactant, J. O. Kim, Purush K. Terkonda, S. D. Lee

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The objectives of this study were to investigate the biodegradation of gaseous trichloroethylene (TCE) and tetrachloroethylene (PCE) in an activated carbon biofilter inoculated with phenol-oxidizing microorganisms and to study the effect of surfactant concentration below its critical micelle concentration (CMC) on the removal efficiency of TCE or PCE. For the enhanced biofiltration, a biodegradable nonionic surfactant was added to biofilters. The investigation was conducted using two specially built stainless steel biofilters, one for TCE and the other for PCE. The removal efficiency of gaseous TCE was 100% at a residence time of 7 min and its average inlet concentration of …

Emc Applications Of The Emap5 Hybrid Fem/Mom Code, Yun Ji, Todd H. Hubing, Mohammad Wares Ali

Electrical and Computer Engineering Faculty Research & Creative Works

EMAP5 is a numerical software package designed to model electromagnetic problems. It employs the finite element method (FEM) to analyze three-dimensional volumes, and the method of moments (MOM) to analyze the current distribution on the surface of these volumes. The two methods are coupled through the fields on the dielectric surface. This paper describes the formulation of the EMAP5 code and demonstrates how it can be used to analyze simple printed circuit board configurations

Belted Work Machine, J. J. Burckhartzmeyer, E. R. Crabb, T. F. Lehnhoff, A. L. Watson Jr.

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A heavy duty belt laying work machine includes a frame, a driver wheel mounted in supporting relation to the frame on each lateral side thereof, an idler wheel assembly disposed on each lateral side of the frame. The idler wheel assembly includes an idler wheel and a carry-roller, each of which is rotatably connected to an idler support arm that is pivotally mounted in supporting relation to the frame. A mid-roller is disposed on each lateral side of the frame between the driver wheel and the idler wheel assembly and rotatably connected to a mid-roller support arm mounted in supporting …

Metal-Organic Chemical Vapor Deposition Of Sr-Co-Fe-O Films On Porous Substrates, C.-F. Xia, P. Atanasova, Robert W. Schwartz, T. L. Ward

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Aerosol-assisted chemical vapor deposition using the b-diketonate precursors Sr(tmhd)2•2H2O, Fe(tmhd)3 and Co(tmhd)3 was investigated for depositing thin films of the mixed-conducting ceramic SrCoyFe1-yO3-d onto porous a-Al2O3 substrates. Single-phase SrCoyFe1-yO3-d perovskite films were obtained at a deposition temperature of 550°C and pressure of 15 mm Hg, whereas deposition at atmospheric pressure produced mixed-phase films. The Co/Fe elemental ratios in the films reflected those in the precursor solution, but the films were depleted in Sr. Reduced-pressure deposition provided a more uniform film morphology than atmospheric-pressure, and led to a supported film which was leak-tight to N2 flow.

Robustness Analysis Of Hopfield And Modified Hopfield Neural Networks In Time Domain, Jie Shen, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A variant of the Hopfield network, called the modified Hopfield network is formulated. This network which consists of two mutually recurrent networks has more free parameters than the well-known Hopfield network. Stability analysis of this network is presented. The analysis is carried out in the time domain with an application of the Lyapunov method and robust control Lyapunov function. The current flow in the network is treated as a "control". This "controller" is shown to guarantee "a practically stabilizing control". Analysis of the Hopfield network is also included for completion.

Experimental Testing And Modeling Of Automotive Automatic Belt Tensioners, Jiaxin Zhao, Clark R. Barker, Larry Oliver, William Breig, Joey Edson

Mining Engineering Faculty Research & Creative Works

Automatic belt tensioners are used in serpentine belt drive systems in many automotive front end accessory drive (FEAD) applications. The dynamic characteristics of the tensioner must be well defined in order to accurately model the entire belt drive system for system simulation studies. In order to determine required tensioner performance parameters, six different configurations of a production unit were tested over a wide range of frequencies at two different amplitudes of the arm travel. Data was recorded to define the total torque generated by the tensioner as a result of the known input motion to which the arm was subjected. …

Aerodynamic Interference For Hypersonic Missiles At Low Angle Of Attack, Harlan F. Nelson, Derek G. Hillstrom

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A Euler code is used to predict the flow field over a hypersonic missile and to determine the carryover factors KW(B), fin lift in the presence of the body, and KB(W), lift produced by the body in the presence of the fins. The missile is assumed to have cruciform, delta fins in the + orientation and an aspect ratio of 1.529. Results are presented as a function of fin span at Mach 6, 8, and 10, for a 2-deg angle of attack. Two ratios of specific heats, 1.4 and 1.3, are considered to partially account for vibrational excitation effects. Both …

An Mdo-Compatible Method For Robust Design Of Vehicles, Systems, And Components, Leslie D. Liaw, Richard I. Devries, Donald L. Cronin

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A CAE simulation process was developed to quantify the variability of vehicle attributes such as safety, durability, vehicle dynamics, NVH and weight. The process was integrated with the Ford multi-function optimization (MFO) tool — MOVE (Multi-Function Optimization Visualization Environments) in order to facilitate the robust design of vehicles, systems and components. The statistics of vehicle attribute responses are computed given the statistics of the design parameters. The response surface approximation was used to simplify the input and output relationships. A variety of statistical distributions can be selected to match the statistics of the design parameters which are continuous or discrete. …

An Analog Vlsi Circuit Implementing An Orthogonal Continuous Wavelet Transform, Dongwei Chen, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

We have developed the theory and analog hardware implementation for a Continuous Wavelet Transform (CWT). This novel circuit performs an orthogonal decomposition of temporal signals, such as speech, in a frequency range of 10 Hz to 20 kHz. This multiresolution processor expands the Laguerre structure originally developed by Lee (1960).

An Automated State Model Generation Algorithm For Simulation/Analysis Of Power Systems With Power Electronic Components, Steven Pekarek, E. A. Walters, T. L. Skvarenina, O. Wasynczuk

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a recently developed algorithmic method of deriving the state equations of power systems containing power electronic components is described. Therein the system is described by the pertinent branch parameters and the circuit topology; however, unlike circuit-based algorithms, the difference equations are not implemented at the branch level. Instead, the composite system state equations are established. A demonstration of the computer implementation of this algorithm to model a variable-speed, constant-frequency aircraft generation system is described. Because of the large number of states and complexity of the system, particular attention is placed on the development of a model structure …

Determination Of Aircraft Orientation For A Vision-Based System Using Artificial Neural Networks, Sanjeev Agarwal, Subhasis Chaudhuri

Electrical and Computer Engineering Faculty Research & Creative Works

An algorithm for real-time estimation of 3-D orientation of an aircraft, given its monocular, binary image from an arbitrary viewing direction is presented. This being an inverse problem, we attempt to provide an approximate but a fast solution using the artificial neural network technique. A set of spatial moments (scale, translation, and planar rotation invariant) is used as features to characterize different views of the aircraft, which corresponds to the feature space representation of the aircraft. A new neural network topology is suggested in order to solve the resulting functional approximation problem for the input (feature vector)-output (viewing direction) relationship. …

Electrochemical Characterization Of Copper Deposited On Plasma And Thermally Modified Titanium Surfaces, K. S. Teng, J. L. Delplancke, Jiangfan Zhang, T. J. O'Keefe

Electrical and Computer Engineering Faculty Research & Creative Works

Thin oxide films were grown at temperatures from 373 to 1073 K in plasma and in air on commercially pure titanium substrates. It was determined that the color, thickness, composition, phase, and polarization behavior in a copper electrolyte varied with operating conditions: temperature, oxygen partial pressure, and plasma composition. High-temperature and high oxygen partial pressure plasma produced a thick oxide film. The surface film structure transformed from TiO2 (anatase) to TiO2 (rutile) at a temperature of 600 °C. A lower oxide of the form TinO2n-1, such as Ti2O3 (which may be porous) or possibly Ti3O5, was formed on a thermally …

Magnetoresistance Of Magnetic Tunnel Junctions In The Presence Of A Nonmagnetic Layer, Shi C. Zhang, P. M. Levy

Materials Science and Engineering Faculty Research & Creative Works

We find that electron propagation across a uniform nonmagnetic metallic layer di in a magnetically layered structure is coherent up to a critical length dc. This provides a possible explanation for the slow decay of the magnetoresistance of magnetic tunnel junctions when a layer of Cu or Ag is inserted between the magnetic electrode and the barrier. However, for many (most) structures the roughness of the interfaces breaks the coherence for di ≪ dc. While the loss of coherence is not fatal for the magnetoresistance of metallic multilayers, it is for tunnel junctions. The quantum well states arising from the …

Evolution Of In Situ Refractories In The 20th Century, William E. Lee, Robert E. Moore

Materials Science and Engineering Faculty Research & Creative Works

A common theme over the past 100 years in refractories science and technology has been to generate a protective refractories layer in a high-temperature container, often by reaction of the refractory materials with the contents (glass, slag, or atmosphere). The history of refractories during the 20th century is used in this review to illustrate how techniques - such as slag splashing, in situ spinel generation in castables, magnesia dense layer formation in magnesia-carbon brick in steelmaking, clinker adhesion in cement kilns, and viscous boundary layer generation in glass tanks - have evolved to their present status.

Maskless, Direct Deposition Of Copper Onto Aluminum Bond Pads For Flip Chip Applications, M. Fang, Thomas J. O'Keefe, M. Stroder, W. Shih, Matthew O'Keefe, R. Strawser, D. Via

Materials Science and Engineering Faculty Research & Creative Works

Flip chip interconnection of integrated circuits (IC) for packaging applications such as direct chip attachment use Pb-Sn solders as the connection between the die and the substrate. Under bump metallization is typically used to transition from the non-solderable Al bond pad on the IC to a solderable surface such as copper using traditional blanket metal deposition, photolithography and etching procedures. In this study, we report for the first time the use of a novel process for selectively depositing adherent copper directly onto aluminum thin films, eliminating the need for adhesion promoting transition layers and additional patterning steps. Utilizing copper bearing …

Investigation Of A Complex Reaction Network: Ii. Kinetics, Mechanism And Parameter Estimation, Y. Jiang, M. R. Khadilkar, M. (Muthanna) H. Al-Dahhan, M. P. Duduković, S. K. Chou, G. Ahmed, R. Kahney

Chemical and Biochemical Engineering Faculty Research & Creative Works

Conventional Strategies for Discrimination of Intrinsic and Apparent Kinetics from Crushed- and Whole-Catalyst-Pellet Experimental Data, Respectively, Do Not Yield Satisfactory Results for the Reaction Network in the Manufacture of Α-Aminomethyl-2-Furanmethanol (Aminoalcohol) from Α-Nitromethyl-2-Furanmethanol (Nitroalcohol). Laboratory Trickle-Bed Reactor Tests in the Range of Concentration and Product Yield of Commercial Interest Are Utilized to Yield a Reasonable Set of Kinetic Parameters, Which Are Otherwise Unobtainable. This is Accomplished by Proposing a Reaction Network, a Plausible Mechanism, and Optimizing the Kinetic Parameters based on the Reactor-Model-Generated Performance Data to Fit Experimental Output Concentrations of All Species for the Entire Set of Experiments. a …

Simulation Of Madmel Power Systems Components, Timothy L. Skvarenina, Oleg Wasynczuk, Paul C. Krause, Steven Pekarek

Electrical and Computer Engineering Faculty Research & Creative Works

Detailed computer models of system components for More Electric Aircraft have been developed using the Advanced Control System Language (ACSL) and its graphical front-end, Graphic Modeller. Among the devices modeled are a wound-rotor synchronous generator with parallel bridge-rectifier outputs, a switched-reluctance generator, and various loads including a DC-DC converter, an inverter-driven induction motor, and an electro-hydrostatic actuator. Results from the simulations are presented together with corroborating experimental test results. Copyright © 1998 Society of Automotive Engineers, Inc.

Open Hemispherical Imaging Dielectric Resonator With Whispering Gallery Modes, Sergey Kharkovsky, Z. E. Eremenko, Yuri F. Filipov

Electrical and Computer Engineering Faculty Research & Creative Works

The imaging dielectric resonators with whispering gallery modes (WGMs) for the creation of a new class of millimeter wave solid-state oscillators, devices for the investigation of high temperature superconductors, were suggested. They contain a dielectric element as a semidisk or a cylinder or a hemisphere and a flat metal mirror. The latter is a necessary element for placing in the resonator field active elements or conductor samples of materials. There is an important question about the dependence of the resonant frequencies and Q-factor of these resonators on impedance of the resonator mirror. In the present paper new investigation results of …

Expedient Method To Determine Active Zone Depth For Expansive Soils In The St. Louis, Missouri Area, Robert Allen Abbott

Masters Theses

"A laboratory testing program was developed to formulate a relationship which could be used to estimate the active zone depth at a given site with the index properties of the potentially expansive soils at the site. The testing program utilized standard consolidometers to incrementally add moisture to soil specimens to determine a swell versus soil suction index. Tests were performed on laboratory manufactured soil specimens of commercial clay to validate the testing methodology.

A QUATTRO PRO computer spreadsheet was developed to perform the calculations to determine the potential field surface heave for the soils tested provided they were at a …

Statistical Analysis Of Structural Response Via A Quadratic Regression Model, Mahesh Balasubramanian

Masters Theses

"Described herein is the development of an efficient capability to analyze the statistics of structural responses given a description of the statistics of the input, or design, variables. In the application of interest, inputs and outputs are related through a very large finite element model. The finite element model is approximated here by a second-order hyper-surface. Developed for the quadratic relationship are expressions for response means, standard deviations and correlation coefficients. The analysis allows correlated and uncorrelated input variables, and admissible input variable distributions are normal, log-normal and Weibull.

In addition to characterizations of response means, standard deviations and correlation …

Methods For Predicting Shale Durability In The Field, Paul Michael Santi, Jerry D. Higgins

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Durability of shales and other weak rock is an important parameter describing the material's susceptibility to breakdown upon exposure to water or during construction work. While laboratory methods have been developed to measure durability, no correlations between laboratory results and simple field tests have been determined. The results of this study show that certain field parameters can predict slake durability with acceptable accuracy. The recommended field tests, in order of desirability, are slake index, jar slake, hammer rebound, and NGI "Q" value. Single variable and multiple variable linear regression equations are given, including equations conservatively modified so that 95% of …

A Hybrid System For Well Test Analysis, Edward A. May, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

Petroleum well test analysis is a tool for estimating the average properties of the reservoir rock. It is a classic example of an inverse problem. Visual examination of the pressure response of the reservoir to an induced flow rate change at a well allows the experienced analyst to determine the most appropriate model from a library of generalized analytical solutions. Rock properties are determined by finding the model parameters that best fit the observed data. This paper describes a framework for hybrid network to assist the analyst in selecting the appropriate model and determining the solution. The hybrid network design …

An Object-Based Evolutionary Algorithm: The Nesting Solution, Kanchitpol Ratanapan, Cihan H. Dagli

Engineering Management and Systems Engineering Faculty Research & Creative Works

The nesting problems have received considerable attention and have been addressed by a variety of algorithms. Recently, evolutionary algorithms have been adopted for solutions. Most of these algorithms, however, require a search in one-dimensional space; thus a transformation of the problem to a single dimension, as in the sequencing problems, is needed. Unfortunately, this restricts the search space. In this study an object-based evolutionary algorithm for the nesting problems is proposed. The methodology is created in a true two-dimensional space, allowing object-based mechanisms and object-based evolutionary operators to perform effectively on the space without restricting search alternatives. Implementation of the …

A Novel Thin Film Transistor Using Double Amorphous Silicon Active Layer, Jong Hyuni Choi, Chang-Soo Kim, Byung Cheon Lim, Jin Jang

Electrical and Computer Engineering Faculty Research & Creative Works

We have fabricated a novel low off-state leakage current thin-film transistor (TFT) using a chlorine incorporated amorphous silicon [a-Si:H(:Cl)] and amorphous silicon (a-Si:H) stacked active layer, in which conduction channel is formed in a-Si:H and a-Si:H(:Cl) is photo-insensitive material. The off-state photo-leakage current of the a-Si:H(:Cl)/a-Si:H TFT is much lower than that a conventional a-Si:H TFT.

A Robust Unit Commitment Algorithm For Hydro-Thermal Optimization, Chao-An Li, R. B. Johnson, A. J. Svoboda, Chung-Li Tseng, E. Hsu

Engineering Management and Systems Engineering Faculty Research & Creative Works

This paper presents a unit commitment algorithm which combines the Lagrangian relaxation (LR), sequential unit commitment (SUC), and optimal unit decommitment (UD) methods to solve a general hydro-thermal optimization (HTO) problem. We argue that this approach retains the advantages of the LR method while addressing the method''s observed weaknesses to improve overall algorithm performance and quality of solution. The proposed approach has been implemented in a version of PG&E''s HTO program, and test results are presented.

The Effect Of A Baffle On Acoustic Radiation Directivity, Walter Eversman, Indranil Danda Roy

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An investigation is made of the effect of an artificial baffle introduced in Finite Element modeling of acoustic radiation from turbofan inlets. The purpose of the baffle is to limit the extent of the computational domain in order to maximize the efficiency of the scheme. However, the possibility exists that the baffle, if improperly oriented, will generate spurious reflections which interfere with the true radiated acoustic field. A generic example of a turbofan inlet, including typical geometry and non-uniform potential flow in and around the nacelle, is modeled with a baffle as typically introduced limiting the angular extent of the …