Engineering Commons^™

Neural Network Architecture For Solving The Algebraic Matrix Riccati Equation, Fredric M. Ham, Emmanuel G. Collins

Electrical Engineering and Computer Science Faculty Publications

This paper presents a neurocomputing approach for solving the algebraic matrix Riccati equation. This approach is able to utilize a good initial condition to reduce the computation time in comparison to standard methods for solving the Riccati equation. The repeated solutions of closely related Riccati equations appears in homotopy algorithms to solve certain problems in fixed-architecture control. Hence, the new approach has the potential to significantly speed-up these algorithms. It also has potential applications in adaptive control. The structured neural network architecture is trained using error backpropagation based on a steepest-descent learning rule. An example is given which illustrates the …

Similarity-Based Learning For Pattern Classification, Laurene V. Fausett

Electrical Engineering and Computer Science Faculty Publications

Several standard neural networks, including counterpropagation networks, predictive ART networks, and radial basis function networks, are based on a combination of clustering (unsupervised learning) and mapping (supervised learning). A comparison of the characteristics of these networks for pattern classification problems is presented.

Determination Of Adaptively Adjusted Coefficients For Hopfield Neural Networks Utilizing The Energy Function, Chiyeon Park, Donald W. Fausett

Electrical Engineering and Computer Science Faculty Publications

With its potential for parallel computation and general applicability, the Hopfield neural network has been investigated and improved by many researchers in order to extend its usefulness to various combinatorial problems. In spite of its success in several applications within different energy function formulations, determination of the energy coefficients has been based primarily on trial and error methods since no practical and systematic way of finding good values has been available preciously, although some theoretical analyses have been presented. In this paper, we present a methodical procedure which adaptively determines the energy coefficients leading to a valid solution as the …

Partial Least-Squares Regression Neural Network (Plsnet) With Supervised Adaptive Modular Learning, Fredric M. Ham, Ivica Kostanic

Electrical Engineering and Computer Science Faculty Publications

We present in this paper an adaptive linear neural network architecture called PLSNET. This network is based on partial least-squares (PLS) regression. The architecture is a modular network with stages that are associated with the desired number of PLS factors that are to be retained. PLSNET actually consists of two separate but coupled architectures, PLSNET-C for PLS calibration, and PLSNET-P for prediction (or estimation). We show that PLSNET-C can be trained by supervised learning with three standard Hebbian learning rules that extracts the PLS weight loading vectors, the regression coefficients, and the loading vectors for the univariate output component case …

Efficient Buffer Allocation Scheme For Bursty Traffic In Atm Networks Using Fast Reservation Protocol, Nikhil Mukund Deshpande

Dissertations and Theses

One of the major problems in the realization of ATM is traffic management, in particular, the resource allocation for an efficient network. Many approaches to the bandwidth management problems [2] and buffer management problems have been proposed. Boyer [10] suggested a "Fast Bandwidth Reservation" protocol, while Turner [2] applied the same technique to the buffer allocation for the bursty traffic. In this thesis, we extend Turner's scheme in order to make it more efficient with respect to buffer allocation. We define a new parameter "Reduction Factor'', which has the potential of saving a significant amount of buffer space in a …

Testing Of Concrete Under Closed-Loop Control, Ravindra Gettu, Barzin Mobasher, Sergio Carmona, Daniel C. Jansen

Civil and Environmental Engineering

Closed-loop testing systems provide the ability to directly control the deformation of the loaded specimen. This considerably enhances the precision, stability, and scope of the experiments. Closed-loop machines can be used to determine the stable response of test specimen or structure by monitoring and controlling the physical quantities that are sensitive to its behavior. The importance of the various components of the closed-loop controlled system and the test configuration is reviewed in the paper. The most critical aspect of designing the test is the choice of the controlled variable. With appropriate controlled variables and good system performance, several interesting and …

Proceedings: Seventeenth Vertebrate Pest Conference, Rohnert Park, California, March 5-7, 1996 (Complete Work), Robert M. Timm , Editor, A. Charles Crabb , Editor

Vertebrate Pest Conference Proceedings: 17th (1996)

340 registered attendees
58 papers
273 pages
52 Mb

You have come from throughout California, from across the United States, and from many corners of the world to gather here for the purpose of sharing information, expertise, and wisdom in dealing with vertebrate pest problems. Our common purpose is to find yet better methods for preventing and resolving situations in which wildlife comes into conflict with humans. The Conference's mission remains one of education. We learn from each other, and we strive to find better ways of applying our knowledge to real-world problems.

Acuta Enews March 1996, Vol. 25, No. 3

ACUTA Newsletters

In This Issue

From the President

Seeking a Wireless Solution

DC at a Glance

Telecom & Leg/Reg Listserves

From ACUTA Headquarters

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 12, Number 3, March 1996, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Towards Rational Trade Offs Between Environment And Hydro-Power, V Ranganathan

IIMB Management Review

The economic importance of hydro-power has long been recognised the world over. In fact, a certain correlation between exploitation of hydropower potential and economic growth is clearly discernible. Developed nations of North America and Western Europe, for example, have exploited 83% and 98%, respectively, of their potential hydro- power, while relatively poorer East European, Asian and African countries have a much lower record, ranging between 8% and 36% (see chart). Recent trends in hydro-power development in India are a source of serious concern: for instance, the hydro-thermal ratio of power generation in the country has been steadily declining from 1:1 …

Calibration Of Spaceborne Scatterometers Using Tropical Rain Forests, David G. Long, Gary B. Skouson

Faculty Publications

Wind scatterometers are radar systems designed specifically to measure the normalized radar backscatter coefficient (O) of the ocean's surface in order to determine the near-surface wind vector. Postlaunch calibration of a wind scatterometer can be performed with an extended-area natural target such as the Amazon tropical rain forest. Rain forests exhibit a remarkably high degree of homogeneity in their radar response over a very large area though some spatial and temporal variability exist. The authors present a simple technique for calibrating scatterometer data using tropical rain forests, Using a polynomial model for the rolloff of O with incidence angle, the …

Generalized Hidden Filter Markov Models Applied To Speaker Recognition, John M. Colombi

Theses and Dissertations

Classification of time series has wide Air Force, DoD and commercial interest, from automatic target recognition systems on munitions to recognition of speakers in diverse environments. The ability to effectively model the temporal information contained in a sequence is of paramount importance. Toward this goal, this research develops theoretical extensions to a class of stochastic models and demonstrates their effectiveness on the problem of text-independent (language constrained) speaker recognition. Specifically within the hidden Markov model architecture, additional constraints are implemented which better incorporate observation correlations and context, where standard approaches fail. Two methods of modeling correlations are developed, and their …

A Crosstalk Correcting Router That Uses Online Noise Simulation To Route High-Speed Multichip Modules, Kenneth J. Mcclellan Jr.

Theses and Dissertations

Existing Multi Chip Module (MCM) auto-routers either ignore crosstalk or use over-simplified crosstalk approximations. Of the routers that do consider crosstalk, very few have the capability to correct crosstalk problems after they occur. This dissertation describes a router that not only has an internal crosstalk model for high speed MCMs which is more accurate than that of other existing routers, but also has the capability to use an online simulator to more accurately determine noise levels. After crosstalk problems occur, the router has the ability to correct these problems. Through memory usage reductions and routing efficiency improvements, this maze router …

Structural Damage Identification From Limited Measurement Data, Richard G. Cobb

Theses and Dissertations

The research focused on the development of a new method to identify damaged structural elements from a large flexible space structure on-orbit, using limited measured modal data. Limited measured modal data is loosely defined as measured data containing only a few modal frequencies and less than 10% of the total structural degrees-of-freedom. This effort was decomposed into four specific tasks. The first is the identification of partial modal properties from measured data of the nominal space structure. Second, the finite element model must be adjusted to match the measured nominal partial data. The third task is an analysis of the …

Modeling Of Progressive Damage In Fiber-Reinforced Ceramic Matrix Composites, James P. Solti

Theses and Dissertations

An analytic methodology is developed to model the response of fiber-reinforced ceramic matrix composites (CMOs) when subjected to monotonic and fatigue loadings. The analysis requires the formulation of (1) a micromechanics model which defines the laminate's geometry and constitutive relationship; (2) failure criteria which estimate the extent of microstructural damage, and, finally, (3) a means of analyzing frictional slip, fiber pull-out, interfacial wear and laminate failure. For the present study, the behavior of unidirectional and crossply CMOs is investigated using modified shear-lag theory in conjunction with a set of failure criteria with a minimum reliance on empirical data. The damage …

Compressible Turbulence Measurements In A Supersonic Boundary Layer With Impinging Shock Wave Interaction, Michael J. Meyer

Theses and Dissertations

No abstract provided.

An Investigation Into The Effects Of Lateral Aerodynamic Asymmetries, Lateral Weight Asymmetries, And Differential Stabilator Bias On The F-15 Directional Flight Characteristics At High Angles Of Attack, David R. Evans

Theses and Dissertations

The F-15 is a stable aircraft throughout most of its flight envelope. However, it still exhibits an uncommanded yawing and rolling tendency at high angles-of-attack. Identified influencing factors of this uncommanded motion are lateral aerodynamic asymmetries, lateral weight asymmetries, and differential stabilator bias. Previous research into the effects of these influencing factors has been qualitative. This thesis quantifies the effects and then identifies a symmetric F-15 configuration. The quantifying metric presented is net yaw acceleration. This thesis used both computer simulation and experimental flight test to quantify these effects. A discussion of each influencing factors effects on the F-15B high …

Comparison Of The Control Anticipation Parameter And The Bandwidth Criterion During The Landing Task, David A. Kivioja

Theses and Dissertations

Many handling qualities criteria have been developed which predict pilot opinion of landing aircraft. MIL-STD-1797A, 'Flying Qualities of Piloted Aircraft' lists six different criteria. However, applying all six criteria to one aircraft can lead to conflicting results. The Air Force Institute of Technology (AFIT) along with the Flight Dynamics Laboratory have conducted research to evaluate differences among the handling qualities criteria in MIL-STD-1797A. The overall objective of this thesis was to determine similarities and discrepancies between the Control Anticipation Parameter (CAP) and bandwidth criteria, and to evaluate the advantage of including a dropback criterion with the bandwidth criterion. Results of …

Modeling Space In The Air Force Command Exercise System (Aces), Robert Payne Jr.

Theses and Dissertations

In response to the increased influence of space forces on today's battlefield, several theater level models were analyzed for the presentation of space forces. These models were the Extended Air Defense Simulation (EADSIM), the Joint Theater Level Simulation (JTLS), the Integrated Theater Engagement Model (ITEM), the Tactical Warfare Model (TACWAR), Thunder, Janus, and the Aggregate Level Simulation Protocol (ALSP). While ALSP is not a model but a simulation protocol connecting various models, it was studied because it appears to be the future of modeling. The consensus of the analysis was that space forces are virtually ignored by most of the …

International Space Station Traffic Modeling And Simulation, Jillene B. Rylaarsdam

Theses and Dissertations

In an effort to provide NASA with an alternative perspective and some insights to the operational planning of the International Space Station (ISS), this research developed a simulation environment for the ISS and devised a method to evaluate various altitude strategies. The simulation environment allowed us to incorporate the natural random behaviors which affect the lifetime of objects in low earth orbit. We created prototype models of the operational planning process to analyze current altitude strategy approaches and acquire new strategies from insights observed. In addition, by extrapolating random future solar activity values from the interpolation of historical data, we …

Text-Independent, Open-Set Speaker Recognition, Stephen V. Pellissier

Theses and Dissertations

Speaker recognition, like other biometric personal identification techniques, depends upon a person's intrinsic characteristics. A realistically viable system must be capable of dealing with the open-set task. This effort attacks the open-set task, identifying the best features to use, and proposes the use of a fuzzy classifier followed by hypothesis testing as a model for text-independent, open-set speaker recognition. Using the TIMIT corpus and Rome Laboratory's GREENFLAG tactical communications corpus, this thesis demonstrates that the proposed system succeeded in open-set speaker recognition. Considering the fact that extremely short utterances were used to train the system (compared to other closed-set speaker …

The Effects Of Changing Force Structure On Thunder Output, Michael R. Farmer

Theses and Dissertations

In today's reduction of America's national defense, campaign level models are being used more in the development of force structure. The effects of drawdown are of significant interest to those at the highest levels of authority. Campaign models can bring those high ranking officials the answers they seek with high confidence. THUNDER is a campaign model used frequently by the United States Air Force and many of its contractors. The effects of changing the force structure within THUNDER require modifying variables before executing a new experimental run. Changes in such issues as force structure cannot be immediately addressed. Response Surface …

Replicative Use Of An External Model In Simulation Variance Reduction, Thomas H. Irish

Theses and Dissertations

The use of control variates is a well-known variance reduction technique for discrete event simulation experiments. Currently, internal control variates are used almost exclusively by practitioners and researchers when using control variates. The primary objective of this study is to explore the variance reduction achieved by the replicative use of an external, analytical model to generate control variates. Performance for the analytical control variates is compared to the performance of typical internal and external control variates for both an open and a closed queueing network. Performance measures used are confidence interval width reduction, realized coverage, and estimated Mean Square Error. …

Requirement For C-130 Aircraft In The Intratheater Korean Scenario, Philip B. Oglesby

Theses and Dissertations

In an effort to provide a timely and reasonably accurate methodology for determining C-130 intratheater airlift requirements, this research concentrated on a rough-cut capacity approach using a straight forward linear programming spreadsheet model. To provide more detailed analysis, a more sophisticated linear program was investigated. Specifically, the spreadsheet model calculated the minimum number of C-130s required to carry required cargo, passenger, and aeromedical loads based on user-defined daily requirements. For a given scenario, inputs include the daily requirements and the expected capacity for C-130 aircraft, trucks, and 22-car trains. Included in the capacity inputs are the number of daily cycles …

Forecasting And Explanatory Models For Middle Eastern Defense Budgets: A Case Study Of Saudi Arabia, Robert S. Renfro Ii

Theses and Dissertations

This thesis focuses on means of forecasting Saudi Arabian military expenditures and the effect of such expenditures on the United States. Saudi Arabia is one of the largest purchasers of American arms and will continue to be for many years. Saudi Arabia has experienced several recent changes in economic and government policy. Using exponential smoothing techniques and linear regression, we isolated several trends in Saudi Arabian military expenditures. Using two linear regression models, military expenditures were then forecast with excellent results. The first model considered the assumption that Gulf War spending would continue. This model uses Saudi Arabian Gross Domestic …

Airlift System Sensitivity To Perturbed Time-Phased Force Deployment Data, Glenn G. Rousseau

Theses and Dissertations

This research evaluated the effects of perturbations in time phased force deployment data (TPFDD) on airlift system performance. Four characteristics of two TPFDD files were perturbed according to a 2(4-1) fractional factorial experimental design and then fed into the Airlift Flow Module (AFM) simulation. Specifically, small, constrained perturbations were made to the specified locations, the timeline, the amounts of cargo and passengers, and the proportion of outsize and oversize cargo categories. The effects these perturbations had on AFM output were interpreted using factor analysis. The computed factor scores, when plotted against one another, provided sensitivity plots, graphically depicting the sensitivity …

Estimating Risks In Emerging Soil Remediation Technologies, Thomas J. Timmerman

Theses and Dissertations

The Department of Energy is focusing a long-term development effort on producing cheaper, safer, and faster state-of-the-art soil remediation technologies. To assist with the management of these innovative technology development projects, ways of quantifiably measuring technical risk were investigated through a detailed literature review. 'Technical risk' was defined in this study as the combination of the consequences of undesired events and their likelihood. Careful design of the inputs into a technology selection decision support system accounted for the uncertainty in forecasting final characteristics of remediation technologies still in the early phases of R&D. Experts made subjective probability estimates of these …

Modeling Diminishing Marginal Returns: An Application To The Aircraft Availability Model, Wayne L. Zorn

Theses and Dissertations

The Aircraft Availability Model (AAM) provides the Air Force with a worldwide peacetime requirement for reparable spare parts. This research models AAM methodology as it relates to the concept of diminishing marginal returns in resource application. Three separate modeling techniques are investigated with the goal of reformulating the AAM as a mathematical programming model that provides a comparable solution and a capable tool for the conduct of sensitivity analysis. The general formulations presented here are continuous non-linear, continuous linear, and piecewise linear discrete/continuous models. Two formulations of the piecewise linear discrete/continuous model are presented. The piecewise linear model based on …

Performance Study Of Shared Versus Nonshared Bandwidth On A Packet-Switched Network, John P. Stevens

Theses and Dissertations

In wide area computer data communications, many networks have evolved by satisfying increased user demands in the most expedient manner. In some cases, new users’ demands are satisfied by installing a new link, rather than sharing the links that are already in place. This research investigates the differences in performance between using a dedicated link for each source destination pair (nonshared bandwidth) and using a single link to be used by all source destination pairs (shared bandwidth). Simulation models are developed for a wide area network using shared bandwidth, and a wide area network using nonshared bandwidth. The quality of …

Modeling Mobility Engineering In A Theater Level Combat Model, Brian K. Hobson

Theses and Dissertations

This thesis describes the development of a methodology to model theater-level mobility engineering assets in the Joint Staff's Joint Warfare Analysis Experimental Prototype (JWAEP) and to quantify the joint and Army doctrine that guides the task organization of engineers for combat and which quantifies engineer mobility effects in combat. The methodology incorporates theater-level mobility engineering assets into the JWAEP by using Mission, Enemy, Troops available, Terrain, and Time (MET-T principles which reflect joint and Army doctrine, and combines them with the existing basic concepts in other theater-level models. Additional aspects of the problem include determining the manmade and natural obstacles' …