Engineering Commons^™

Optimization Of Receptive Fields For Mlp Networks With Ensemble Encoding, Deena Osama Hassan

Archived Theses and Dissertations

Ensemble encoding is a biologically-motivated, distributed data representation scheme for MLP networks. Multiple overlapping receptive fields are used to enhance locality of representation. The number, form, and placement of receptive fields have a great impact on performance. This thesis presents four heuristics, two based on descriptive statistics, and two based on clustering, for optimizing receptive field configuration, and compares their performance on four benchmark data sets. The two statistical approaches are based on the mean and median properties of the data set. The two clustering methods are the c-means and fuzzy c-means clustering. The four data sets used are well-known …

Synthesis And Optimization Of Digital Systems For Low Power At Logic Level Of Abstraction, Ihab Mostafa Amin Amer

Archived Theses and Dissertations

In this thesis we tackle one of the most important fields of research, which is reducing power consumption in digital systems. The importance of this field comes from the fact that nowadays, several digital devices are intensively used in our daily life. Thus, minimizing their power consumption is a common demand from the technological as well as the economical point of view. Some basic definitions in the low power design field are introduced. Besides, a preview of different efforts that were exerted in the field of reducing power consumption of digital systems at various levels of abstraction is presented. A …

Probabilities, Intervals, What Next? Optimization Problems Related To Extension Interval Computations To Situations With Partial Information About Probabilities, Vladik Kreinovich

Departmental Technical Reports (CS)

When we have only interval ranges [xi-,xi+] of sample values x1,...,xn, what is the interval [V-,V+] of possible values for the variance V of these values? We prove that the problem of computing the upper bound V+ is NP-hard. We provide a feasible (quadratic time) algorithm for computing the exact lower bound V- on the variance of interval data. We also provide feasible algorithms that computes V+ under reasonable easily verifiable conditions, in particular, in case interval uncertainty is introduced to maintain privacy in a statistical database.

We also extend the main formulas of interval arithmetic for different arithmetic operations …

Optimization Of An Automotive Generator Using Evolutionary Programming, A. Koenig, J. Williams, Steven Pekarek

Electrical and Computer Engineering Faculty Research & Creative Works

One of the primary design requirements of automotive generation systems is maximizing power density subject to the constraint of minimizing overall system cost. However, with progress made in reduction of automotive drive train noise, the torque ripple of the generator has been found to be a dominant noise source under idle conditions at high electrical load. Thus, an added design constraint is the minimization of torque ripple produced by the machine. in order to meet these objectives, numerical tools have been developed to automate the design process. a primary tool is an evolutionary algorithm that has been integrated within a …

An Extended Kalman Filter (Ekf) Approach On Fuzzy System Optimization Problem, Nian Zhang, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Optimizing the membership functions of a fuzzy system can be viewed as a system identification problem for a nonlinear dynamic system. Basically, we can view the optimization of fuzzy membership functions as a weighted least-squares minimization problem, where the error vector is the difference between the fuzzy system outputs and the target values for those outputs. The extended Kalman filter algorithm is a good choice to solve this system identification problem, not only because it is a derivative-based algorithm that is suitable to solve the weighted least-squares minimization problem, but also because of its appealing predictor-corrector feature for nonlinear system …

Somos Simulation/Optimization Modeling System, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

SOMOS (Simulation / Optimization Modeling System) is a family of simulation / optimization (S/O) modules to aid in optimally managing water resources. SOMOS results from twenty years experience developing optimization models and applying them to real-world problems, including 11 pump-and-treat (PAT) systems and numerous water supply problems. SOMOS significantly improves water management or designs and saves money. Its user’s manual provides excellent training in principles of applying optimization to managing aquifer and stream-aquifer systems. It is being incorporated with powerful groundwater modeling and visualization packages.

Practical Simulation /Optimization Modeling For Groundwater Quality And Quantity Management, Richard C. Peralta, Ineke M. Kalwij, Shengjun Wu

Civil and Environmental Engineering Faculty Publications

Software for mathematically optimizing groundwater management has improved significantly in recent years. The SOMOS code can readily handle large complex plume and water management problems. Most recently, it developed a least-cost $40.82M 30-yr pumping strategy for the 6.58 mile long Blaine NAD plume. That strategy was 19 percent better than the strategy developed simultaneously by an experienced consultant using normal trial and error simulation procedures. The management problem involved 60 stress periods, and well installation and pumping rates that could change every 10 periods. The optimal strategy employed 10 new wells. At a simpler site, SOMOS helped select robust strategies …

Training Radial Basis Neural Networks With The Extended Kalman Filter, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

Radial basis function (RBF) neural networks provide attractive possibilities for solving signal processing and pattern classification problems. Several algorithms have been proposed for choosing the RBF prototypes and training the network. The selection of the RBF prototypes and the network weights can be viewed as a system identification problem. As such, this paper proposes the use of the extended Kalman filter for the learning procedure. After the user chooses how many prototypes to include in the network, the Kalman filter simultaneously solves for the prototype vectors and the weight matrix. A decoupled extended Kalman filter is then proposed in order …

Sum Normal Optimization Of Fuzzy Membership Functions, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

Given a fuzzy logic system, how can we determine the membership functions that will result in the best performance? If we constrain the membership functions to a certain shape (e.g., triangles or trapezoids) then each membership function can be parameterized by a small number of variables and the membership optimization problem can be reduced to a parameter optimization problem. This is the approach that is typically taken, but it results in membership functions that are not (in general) sum normal. That is, the resulting membership function values do not add up to one at each point in the domain. This …

Probabilistic Microcell Prediction Model, Song-Kyoo Kim

Electrical Engineering and Computer Science Faculty Publications

A microcell is a cell with 1-km or less radius which is suitable for heavily urbanized area such as a metropolitan city. This paper deals with the microcell prediction model of propagation loss which uses probabilistic techniques. The RSL (Receive Signal Level) is the factor which can evaluate the performance of a microcell and the LOS (Line-Of-Sight) component and the blockage loss directly effect on the RSL. We are combining the probabilistic method to get these performance factors. The mathematical methods include the CLT (Central Limit Theorem) and the SPC (Statistical Process Control) to get the parameters of the distribution. …

A Simple, Robust, And On-Site Microwave Technique For Determining Water-To-Cement Ratio (W/C) Of Fresh Portland Cement-Based Materials, K. Mubarak, Karl Joseph Bois, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Inspection and evaluation of cement-based materials such as concrete is of great interest to the construction industry. In particular, real-time and on-site evaluation of water-to-cement ratio (w/c) is an important practical issue, since the compressive strength of a concrete structure is significantly influenced by its w/c. Currently, there is no single real-time, on-site, relatively in-expensive, easy-to-implement, and operator friendly technique for evaluating this parameter. Microwave nondestructive testing and evaluation techniques have shown great promise when used for inspection and evaluation of the properties of cement-based materials. In this paper, the optimal design of a monopole antenna probe used to evaluate …

Watershed Management Technique To Control Sediment Yield In Agriculturally Dominated Areas, John W. Nicklow, Misgana K. Muleta

Civil and Environmental Engineering

Non-point source pollution is recognized internationally as a critical environmental problem. In Illinois, soil erosion from agricultural lands is the major source of such pollution. The erosion process, which has been accelerated by human activity, tends to reduce crop productivity and leads to subsequent problems from deposition on farmlands and in water bodies. Comprehensive watershed management, however, can be used to protect these natural resources. In this study, a discrete time optimal control methodology and computational model are developed for determining land use and management alternatives that minimize sediment yield from agriculturally-dominated watersheds. The solution methodology is based on an …

Optimization Of Flow Quality In The Test Section Of The 30-Inch X 40- Inch Subsonic Tunnel, Ahmed F. Elnenaey

Master's Theses - Daytona Beach

The purpose of this study is to optimize the flow quality inside the 30-inch x 40-inch subsonic wind tunnel. The tunnel is an open circuit with its inlet positioned adjacent to the side door of the lab; forcing the air to make a ninety degrees turn entering the tunnel. The flow suffered from two main deficiencies, high level of turbulence and slightly unsteady flow with a non-uniform velocity distribution across the test section. By utilizing a hot-film anemometer system and a total pressure rake, turbulence and velocity distribution data were obtained. Rounded corners and a turning vane were installed in …

Microstructure-Sensitive Design Of A Compliant Beam, Brent L. Adams, Alisa J. Millar Henrie, B. Henrie, M. Lyon, H. Garmestani, Surya R. Kalidindi

Faculty Publications

BA acknowledges financial support provided by the MRSEC Program of the National Science Foundation under Award Number DMR-9632556. SK acknowledges financial support from National Science Foundation under Award Number CMS-9732699. BA, SK and HG also acknowledge support from the NSF-CIRE program centered at Florida A&M University, facilitating collaborations. Support was also provided by the College of Engineering and Technology at BYU (AH, BH and ML). Computations were performed on the new SGI Origin 2000 supercomputer at Brigham Young University, donated by Ira Fulton. We show that mechanical design can be conducted where consideration of polycrystalline microstructure as a continuous design …

Remediation Simulation/Optimization Demonstrations, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Applications of simulation/optimization (S/0) software to develop contamination remediation strategies include formal remediation optimization using heads and gradients (hydraulics-based) and concentrations (risk-based) constraints. The six reported cases involve pump and treat systems, or pump, treat and re-inject systems, together termed PAT systems. We used S/0 modeling to perform hydraulic optimization for two of the sites and transport optimization for four. For four of the six sites, other parties used normal simulation (S) modeling alone to develop pumping strategies. Comparing the S/0 model-developed strategies with the S model-developed strategies showed S/0 modeling benefits ranging up to: (a) 25 percent reduction in …

Simulation/Optimization Applications And Software For Optimal Ground-Water And Conjunctive Water Management, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Diverse water management simulation/optimization (S/O) experiences promoted the development of many S/O modeling approaches and models. Several of these are being incorporated within the Simulation/Optimization Modeling System (SOMOS). Non-modeler water scientists or engineers can apply one SOMOS module to optimize field-scale groundwater and conjunctive water management. Experienced groundwater modelers can apply other modules to optimally manage complex heterogeneous aquifer and stream-aquifer systems. SOMOS employs a variety of simulation models and approaches and optimization algorithms to optimize flow and contaminant management. SOMOS or its precursor modules have been well proven in real-world projects. Designed for use by consultants, students, academics, and …

Computer-Based Methods For Constructing Two-Level Fractional-Factorial Experimental Designs With A Requirement Set, Steven L. Forsythe

Theses and Dissertations

This dissertation developed four methodologies for computer-aided experimental design of two-level fractional factorial designs with requirement sets (DOE/RS). The requirement sets identify all the experimental factors and the appropriate interaction terms to be evaluated in the experiment. Taguchi graphs and similar manual methods provide techniques for solving the DOE/RS problem. Unfortunately, these methods are limited because they become difficult to use as the number of factors or interaction terms exceeds ten. This research showed that the DOE/RS problem belongs to a class of difficult-to-solve problems known as NP-Complete. It is the combinatorial nature of NP-Complete problems that causes them to …

Design And Rule Base Reduction Of A Fuzzy Filter For The Estimation Of Motor Currents, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

Fuzzy systems have been used extensively and successfully in control systems over the past few decades, but have been applied much less often to filtering problems. This is somewhat surprising in view of the dual relationship between control and estimation. This paper discusses and demonstrates the application of fuzzy filtering to motor winding current estimation in permanent magnet synchronous motors. Motor winding current estimation is an important problem because in order to implement effective closed-loop control, a good estimation of the current is needed. Motor winding currents are notoriously noisy because of electrical noise in the motor drive. We use …

Optimal Elimination Of Inconsistency In Expert Knowledge: Formulation Of The Problem, Fast Algorithms, Timothy J. Ross, Berlin Wu, Vladik Kreinovich

Departmental Technical Reports (CS)

Expert knowledge is sometimes inconsistent. In this paper, we describe the problem of eliminating this inconsistency as an optimization problem, and present fast algorithms for solving this problem.

Approximation And Optimization Of An Auditory Model For Realization In Vlsi Hardware, Samuel L. Sangregory

Theses and Dissertations

The Auditory Image Model (AIM) is a software tool set developed to functionally model the role of the ear in the human hearing process. AIM includes detailed filter equations for the major functional portions of the ear. Currently, AIM is run on a workstation and requires 10 to 100 times real-time to process audio information and produce an auditory image. An all-digital approximation of the AIM which is suitable for implementation in very large scale integrated circuits is presented. This document details the mathematical models of AIM and the approximations and optimizations used to simplify the filtering and signal processing …

Water Resources Systems Analysis - Course Notes, A Bruce Bishop, Trevor Hughes, Mac Mckee

All ECSTATIC Materials

Water resources systems analysis course notes for CEE 6410 taught at Utah State University. Coverage includes:

Chapter 1 - Concepts and methods

Chapter 2 - Linear programming-introduction and graphical methods

Chapter 3 - Linear programming - simplex method

Chapter 4 - Linear programming - applications to simple water problems

Chapter 5 - Dual LP and post optimality analysis

Chapter 6 - Integer programming

Chapter 7 - More applications of integer programmign

Chapter 8 - Piecewise linearization

Chapter 9 - Other types of LP models

Chapter 10 - Dynamic programming

Chapter 11 - Gradient-based nonlinear optimization methods

Chapter 12 - Genetic …

Technology Selection For The Air Force Research Laboratory Air Vehicles Directorate: An Analysis Using Value Focused Thinking, Michael F. Winthrop

Theses and Dissertations

A technology selection model was developed for the Air Vehicles Directorate of Air Force Research Laboratory. The model was developed and demonstrated to aid in addressing the question of what technologies Air Vehicles' should invest in to remain consistent with Air Force values. Both Value-Focused Thinking and optimization approaches were used to identify the value of Air Vehicles technology, to provide insights to Air Vehicles' decision-makers, to determine where value gaps might exist with the scored alternatives, and to determine how sensitive the model was to changes. As a demonstration of the approach, seven technologies were scored, representing all three …

Fed-Batch Dynamic Optimization Using Generalized Dual Heuristic Programming, Donald C. Wunsch, M. S. Iyer

Electrical and Computer Engineering Faculty Research & Creative Works

Traditionally fed-batch biochemical process optimization and control uses complicated theoretical off-line optimizers, with no online model adaptation or re-optimization. This study demonstrates the applicability, effectiveness, and economic potential of a simple phenomenological model for modeling, and an adaptive critic design, generalized dual heuristic programming, for online re-optimization and control of an aerobic fed-batch fermentor. The results are compared with those obtained using a heuristic random optimizer

The Significance And Effects Of Oil Injection On The Performance Of Sliding Vane Compressors., M Mkumbwa

Tanzania Journal of Engineering and Technology (TJET)

A computer model of a sliding vane air compressor was used to predict the behaviour of machines having different geometries operating at different conditions. The performance parameters which were calculated by the model were the free air delivery, power input and specific capacity which is defined as the free air delivery per unit of power input.The model also included the study of the effects of Oil injection on these mentioned compressor performance parameters. The paper describes the simulation model developed incorporating an analysis Of the effects of the oil injected into the compressor on lhe thermodynamic processes taking place in …

Trigonometric Transforms For Image Reconstruction, Thomas M. Foltz

Theses and Dissertations

This dissertation demonstrates how the symmetric convolution-multiplication property of discrete trigonometric transforms can be applied to traditional problems in image reconstruction with slightly better performance than Fourier techniques and increased savings in computational complexity for symmetric point spread functions. The fact that the discrete Fourier transform a circulant matrix provides an alternate way to derive the symmetric convolution-multiplication property for discrete trigonometric transforms. Derived in this manner, the symmetric convolution-multiplication property extends easily to multiple dimensions and generalizes to multidimensional asymmetric sequences. The symmetric convolution-multiplication property allows for linear filtering of degraded images via point-by-point multiplication in the transform domain …

Seismic Isolation Of A Highly Skewed, Prestressed Concrete Girder Bridge, Bradley Neil Robson, Issam E. Harik, David L. Allen

Kentucky Transportation Center Research Report

A relatively new approach for designing or retrofitting highway bridges in seismic zones involves isolating the superstructure from the substructure. Through experimental and analytical investigations, this study evaluates the effectiveness of isolating one particular bridge: a highly skewed, prestressed concrete, slab-on-girder bridge. Dynamic testing of the bridge was performed using the pullback, quick-release method. A three dimensional finite element model of the bridge was created. It was refined, or calibrated, to match experimentally determined natural frequencies and mode shapes. Time-history analyzes, using site-specific acceleration records, were conducted for the seismically isolated bridge model and an identical, non-isolated bridge model.

For …

Optimizing Separate Phase Light Hydrocarbon Recovery From Contaminated Unconfined Aquifers, G. S. Cooper, Richard C. Peralta, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

A modeling approach is presented that optimizes separate phase recovery of light non-aqueous phase liquids (LNAPL) for a single dual-extraction well in a homogeneous, isotropic unconfined aquifer. A simulation/regression/optimization (S/R/O) model is developed to predict, analyze, and optimize the oil recovery process. The approach combines detailed simulation, nonlinear regression, and optimization. The S/R/O model utilizes nonlinear regression equations describing system response to time-varying water pumping and oil skimming. Regression equations are developed for residual oil volume and free oil volume. The S/R/O model determines optimized time-varying (stepwise) pumping rates which minimize residual oil volume and maximize free oil recovery while …

An Airlift Hub-And-Spoke Location-Routing Model With Time Windows: Case Study Of The Conus-To-Korea Airlift Problem, David W. Cox

Theses and Dissertations

Traditionally, the United States Air Force's Air Mobility Command (AMC) has used the concept of direct delivery to airlift cargo and passengers from a point of embarkation to a point of debarkation. This study develops an alternative hub-and-spoke combined location-routing integer linear programming prototype model, and uses this model to determine what advantages a hub-and-spoke system offers, and in which scenarios it is better-suited than the direct delivery method. Additionally, the analysis suggests that the C-17 may be better-suited, in certain airlift situations, for theater airlift versus strategic (direct delivery) airlift. The model features the following elements: time windows, cargo …

A Game-Theoretic Improvement Model For Stochastic Networks: Reliability Vs. Throughput, Jeffrey A. Schavland

Theses and Dissertations

Prescriptive models used to allocate resources for network improvement traditionally have used reliability or flow as Measures of Effectiveness (MOEs). Such metrics do not give value to efforts which make a component more difficult to exploit. This study developed an entirely new MOE for stochastic network improvement, flow damage utility, which uses a two person, zero-sum, non-cooperative game to optimize a probabilistic network for an estimate of expected flow minus performance degradation after a worst case component loss. A multiple criteria optimization problem that uses flow damage utility and an analogous, previously developed metric for the reliability problem is used …

The Application Of Sequential Convex Programming To Large-Scale Structural Optimization Problems, Todd A. Sriver

Theses and Dissertations

Structural design problems are often modeled using finite element methods. Such models are often characterized by constraint functions that are not explicitly defined in terms of the design variables. These functions are typically evaluated through numerical finite element analysis (FEA). Optimizing large-scale structural design models requires computationally expensive FEAs to obtain function and gradient values. An optimization approach which uses the SCP sequential convex programming algorithm of Zillober, integrated as the optimizer in the Automated Structural Optimization System (ASTROS), is tested. The traditional approach forms an explicitly defined approximate subproblem at each design iteration that is solved using the method …